Sample records for aberrant abducens nerve

  1. Microsurgical anatomy of the abducens nerve.

    PubMed

    Joo, Wonil; Yoshioka, Fumitaka; Funaki, Takeshi; Rhoton, Albert L

    2012-11-01

    The aim of this study is to demonstrate and review the detailed microsurgical anatomy of the abducens nerve and surrounding structures along its entire course and to provide its topographic measurements. Ten cadaveric heads were examined using ×3 to ×40 magnification after the arteries and veins were injected with colored silicone. Both sides of each cadaveric head were dissected using different skull base approaches to demonstrate the entire course of the abducens nerve from the pontomedullary sulcus to the lateral rectus muscle. The anatomy of the petroclival area and the cavernous sinus through which the abducens nerve passes are complex due to the high density of critically important neural and vascular structures. The abducens nerve has angulations and fixation points along its course that put the nerve at risk in many clinical situations. From a surgical viewpoint, the petrous tubercle of the petrous apex is an intraoperative landmark to avoid damage to the abducens nerve. The abducens nerve is quite different from the other nerves. No other cranial nerve has a long intradural path with angulations and fixations such as the abducens nerve in petroclival venous confluence. A precise knowledge of the relationship between the abducens nerve and surrounding structures has allowed neurosurgeon to approach the clivus, petroclival area, cavernous sinus, and superior orbital fissure without surgical complications. Copyright © 2012 Wiley Periodicals, Inc.

  2. Abducens Nerve in Patients with Type 3 Duane’s Retraction Syndrome

    PubMed Central

    Hwang, Jeong-Min

    2016-01-01

    Background We have previously reported that the presence of the abducens nerve was variable in patients with type 3 Duane’s retraction syndrome (DRS), being present in 2 of 5 eyes (40%) and absent in 3 (60%) on magnetic resonance imaging (MRI). The previous study included only 5 eyes with unilateral DRS type 3. Objectives To supplement existing scarce pathologic information by evaluating the presence of the abducens nerve using high resolution thin-section MRI system in a larger number of patients with DRS type 3, thus to provide further insight into the pathogenesis of DRS. Data Extraction A retrospective review of medical records on ophthalmologic examination and high resolution thin-section MRI at the brainstem level and orbit was performed. A total of 31 patients who showed the typical signs of DRS type 3, including abduction and adduction deficit, globe retraction, narrowing of fissure on adduction and upshoot and/or downshoot, were included. The abducens nerve and any other extraocular muscle abnormalities discovered by MRI were noted. Results DRS was unilateral in 26 patients (84%) and bilateral in 5 patients (16%). Two out of 5 bilateral patients had DRS type 3 in the right eye and DRS type 1 in the left eye. Of the 34 affected orbits with DRS type 3 in 31 patients, the abducens nerve was absent or hypoplastic in 31 eyes (91%) and present in 3 eyes (9%). Patients with a present abducens nerve showed more limitation in adduction compared to patients with an absent abducens nerve (P = 0.030). Conclusions The abducens nerve is absent or hypoplastic in 91% of DRS type 3. Patients with a present abducens nerve showed more prominent limitation of adduction. As DRS type 3 partly share the same pathophysiology with type 1 and 2 DRS, the classification of DRS may have to be revised according to MRI findings. PMID:27352171

  3. Anatomic variation of the abducens nerve in a single cadaver dissection: the "petrobasilar canal".

    PubMed

    Pizzolorusso, Felice; Cirotti, Andrea; Pizzolorusso, Gianfranco

    2017-04-01

    Anatomic variations of the petrosphenoid ligament, Dorello's canal and the course of the abducens nerve have been extensively described over the past years. In the present report of a single cadaver dissection, we describe an unusual course of the abducens nerve at the level of the petrous bone. The right abducens nerve did not enter Dorello's canal, but ran below the petrous bone through a narrow canal in the petrobasilar suture, which we called the "petrobasilar canal". No anatomic variations of the left abducens nerve were noted.

  4. Detailed anatomy of the abducens nerve in the lateral rectus muscle.

    PubMed

    Nam, Yong Seok; Kim, In-Beom; Shin, Sun Young

    2017-10-01

    The aims of this study were to elucidate the detailed anatomy of the abducens nerve in the lateral rectus muscle (LRM) and the intramuscular innervation pattern using Sihler staining. In this cohort study, 32 eyes of 16 cadavers were assessed. Dissection was performed from the LRM origin to its insertion. The following distances were measured: from LRM insertion to the bifurcation point of the abducens nerve, from LRM insertion to the entry site of the superior branch or inferior branch, from the upper border of the LRM to the entry site of the superior branch, from the lower border of LRM to the entry site of inferior branch, and the widths of the main trunk and superior and inferior branches. The single trunk of the abducens nerve divided into two branches 37 mm from insertion of the LRM, and 22 of 32 (68.8%) orbits showed only two superior and inferior branches with no subdivision. The superior branch entered the LRM more anteriorly (P = 0.037) and the superior branch was thinner than the inferior branch (P = 0.040). The most distally located intramuscular nerve ending was observed at 52.9 ± 3.5% of the length of each muscle. Non-overlap between the superior and inferior intramuscular arborization of the nerve was detected in 27 of 32 cases (84.4%). Five cases (15.6%) showed definite overlap of the superior and inferior zones. This study revealed the detailed anatomy of the abducens nerve in the LRM and provides helpful information to understand abducens nerve palsy. Clin. Anat. 30:873-877, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  5. Horner's syndrome and contralateral abducens nerve palsy associated with zoster meningitis.

    PubMed

    Cho, Bum-Joo; Kim, Ji-Soo; Hwang, Jeong-Min

    2013-12-01

    A 55-year-old woman presented with diplopia following painful skin eruptions on the right upper extremity. On presentation, she was found to have 35 prism diopters of esotropia and an abduction limitation in the left eye. Two weeks later, she developed blepharoptosis and anisocoria with a smaller pupil in the right eye, which increased in the darkness. Cerebrospinal fluid analysis showed pleocytosis and a positive result for immunoglobulin G antibody to varicella zoster virus. She was diagnosed to have zoster meningitis with Horner's syndrome and contralateral abducens nerve palsy. After intravenous antiviral and steroid treatments, the vesicular eruptions and abducens nerve palsy improved. Horner's syndrome and diplopia resolved after six months. Here we present the first report of Horner's syndrome and contralateral abducens nerve palsy associated with zoster meningitis.

  6. Post-traumatic Unilateral Avulsion of the Abducens Nerve with Damage to Cranial Nerves VII and VIII: Case Report.

    PubMed

    Yamasaki, Fumiyuki; Akiyama, Yuji; Tsumura, Ryu; Kolakshyapati, Manish; Adhikari, Rupendra Bahadur; Takayasu, Takeshi; Nosaka, Ryo; Kurisu, Kaoru

    2016-07-01

    Traumatic injuries of the abducens nerve as a consequence of facial and/or head trauma occur with or without associated cervical or skull base fracture. This is the first report on unilateral avulsion of the abducens nerve in a 29-year-old man with severe right facial trauma. In addition, he exhibited mild left facial palsy, and moderate left hearing disturbance. Magnetic resonance imaging (MRI) using fast imaging employing steady-state acquisition (FIESTA) revealed avulsion of left sixth cranial nerve. We recommend thin-slice MR examination in patients with abducens palsy after severe facial and/or head trauma.

  7. Natural history of idiopathic abducens nerve paresis in a young adult.

    PubMed

    Hussaindeen, Jameel Rizwana; Mani, Revathy; Rakshit, Archayeeta; Ramasubramanian, Srikanth; Vittal Praveen, Smitha

    2016-01-01

    The natural history of idiopathic abducens nerve paresis and the role of conservative management such as vision training during the recovery process is not well documented in the literature to the best of our knowledge. This case report presents the natural recovery process of idiopathic abducens nerve paresis in a young adult and the role of vision therapy in the recovery process. Copyright © 2016 Spanish General Council of Optometry. Published by Elsevier España, S.L.U. All rights reserved.

  8. A case of isolated abducens nerve paralysis in maxillofacial trauma

    PubMed Central

    Keskin, Elif Seda; Keskin, Ekrem; Atik, Bekir; Koçer, Abdülkadir

    2015-01-01

    Nervus abducens is a pure motor nerve located in the pons. It retracts the eyeball laterally by stimulating rectus lateralis muscle. In case of their paralysis, diplopia and restriction in the eye movements while looking sideways, are seen. Since the same signs are seen due to the muscle entrapment in blowout fractures, its differential diagnosis has importance in terms of the treatment protocol and avoiding unnecessary operations. In this article, we present a 22-year-old male patient who was referred to our department due to the prediagnosis of blowout fracture following maxillofacial trauma. However, he was diagnosed with abducens nerve paralysis after the consultations and analysis and his restriction of movement was resolved via systemic steroid treatment instead of unnecessary operation. PMID:26981484

  9. Noninvasive transcranial stimulation of rat abducens nerve by focused ultrasound.

    PubMed

    Kim, Hyungmin; Taghados, Seyed Javid; Fischer, Krisztina; Maeng, Lee-So; Park, Shinsuk; Yoo, Seung-Schik

    2012-09-01

    Nonpharmacologic and nonsurgical transcranial modulation of the nerve function may provide new opportunities in evaluation and treatment of cranial nerve diseases. This study investigates the possibility of using low-intensity transcranial focused ultrasound (FUS) to selectively stimulate the rat abducens nerve located above the base of the skull. FUS (frequencies of 350 kHz and 650 kHz) operating in a pulsed mode was applied to the abducens nerve of Sprague-Dawley rats under stereotactic guidance. The abductive eyeball movement ipsilateral to the side of sonication was observed at 350 kHz, using the 0.36-msec tone burst duration (TBD), 1.5-kHz pulse repetition frequency (PRF), and the overall sonication duration of 200 msec. Histologic and behavioral monitoring showed no signs of disruption in the blood brain barrier (BBB), as well as no damage to the nerves and adjacent brain tissue resulting from the sonication. As a novel functional neuro-modulatory modality, the pulsed application of FUS has potential for diagnostic and therapeutic applications in diseases of the peripheral nervous system. Copyright © 2012 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  10. Intramuscular Distribution of the Abducens Nerve in the Lateral Rectus Muscle for the Management of Strabismus.

    PubMed

    Shin, Hyun Jin; Lee, Shin-Hyo; Shin, Kang-Jae; Koh, Ki-Seok; Song, Wu-Chul

    2018-06-01

    To elucidate the intramuscular distribution and branching patterns of the abducens nerve in the lateral rectus (LR) muscle so as to provide anatomical confirmation of the presence of compartmentalization, including for use in clinical applications such as botulinum toxin injections. Thirty whole-mount human cadaver specimens were dissected and then Sihler's stain was applied. The basic dimensions of the LR and its intramuscular nerve distribution were investigated. The distances from the muscle insertion to the point at which the abducens nerve enters the LR and to the terminal nerve plexus were also measured. The LR was 46.0 mm long. The abducens nerve enters the muscle on the posterior one-third of the LR and then typically divides into a few branches (average of 1.8). This supports a segregated abducens nerve selectively innervating compartments of the LR. The intramuscular nerve distribution showed a Y-shaped ramification with root-like arborization. The intramuscular nerve course finished around the middle of the LR (24.8 mm posterior to the insertion point) to form the terminal nerve plexus. This region should be considered the optimal target site for botulinum toxin injections. We have also identified the presence of an overlapping zone and communicating nerve branches between the neighboring LR compartments. Sihler's staining is a useful technique for visualizing the entire nerve network of the LR. Improving the knowledge of the nerve distribution patterns is important not only for researchers but also clinicians to understand the functions of the LR and the diverse pathophysiology of strabismus.

  11. Non-invasive transcranial stimulation of rat abducens nerve by focused ultrasound

    PubMed Central

    Kim, Hyungmin; Taghados, Seyed Javid; Fischer, Krisztina; Maeng, Lee-So; Park, Shinsuk; Yoo, Seung-Schik

    2012-01-01

    Non-pharmacological and non-surgical transcranial modulation of the nerve function may provide new opportunities in evaluation and treatment of cranial nerve diseases. This study investigates the possibility of using low-intensity transcranial focused ultrasound (FUS) to selectively stimulate the rat abducens nerve located above the base of the skull. FUS (frequencies of 350 kHz and 650 kHz) operating in a pulsed mode was applied to the abducens nerve of Sprague-Dawley rats under stereotactic guidance. The abductive eyeball movement ipsilateral to the side of sonication was observed at 350 kHz, using the 0.36 msec tone burst duration (TBD), 1.5 kHz pulse repetition frequency (PRF), and the overall sonication duration of 200 msec. Histological and behavioral monitoring showed no signs of disruption in the blood brain barrier (BBB) as well as no damage to the nerves and adjacent brain tissue resulting from the sonication. As a novel functional neuro-modulatory modality, the pulsed application of FUS has potential in diagnostic and therapeutic applications in diseases of the peripheral nervous system. PMID:22763009

  12. Intrinsic Properties Guide Proximal Abducens and Oculomotor Nerve Outgrowth in Avian Embryos

    PubMed Central

    Lance-Jones, Cynthia; Shah, Veeral; Noden, Drew M.; Sours, Emily

    2012-01-01

    Proper movement of the vertebrate eye requires the formation of precisely patterned axonal connections linking cranial somatic motoneurons, located at defined positions in the ventral midbrain and hindbrain, with extraocular muscles. The aim of this research was to assess the relative contributions of intrinsic, population-specific properties and extrinsic, outgrowth site-specific cues during the early stages of abducens and oculomotor nerve development in avian embryos. This was accomplished by surgically transposing midbrain and caudal hindbrain segments, which had been pre-labeled by electroporation with an EGFP construct. Graft-derived EGFP+ oculomotor axons entering a hindbrain microenvironment often mimicked an abducens initial pathway and coursed cranially. Similarly, some EGFP+ abducens axons entering a midbrain microenvironment mimicked an oculomotor initial pathway and coursed ventrally. Many but not all of these axons subsequently projected to extraocular muscles that they would not normally innervate. Strikingly, EGFP+ axons also took initial paths atypical for their new location. Upon exiting from a hindbrain position, most EGFP+ oculomotor axons actually coursed ventrally and joined host branchiomotor nerves, whose neurons share molecular features with oculomotor neurons. Similarly, upon exiting from a midbrain position, some EGFP+ abducens axons turned caudally, elongated parallel to the brainstem, and contacted the lateral rectus muscle, their originally correct target. These data reveal an interplay between intrinsic properties that are unique to oculomotor and abducens populations and shared ability to recognize and respond to extrinsic directional cues. The former play a prominent role in initial pathway choices, whereas the latter appear more instructive during subsequent directional choices. PMID:21739615

  13. Paralytic squint due to abducens nerve palsy : a rare consequence of dengue fever

    PubMed Central

    2012-01-01

    Background Dengue fever is an endemic illness in the tropics with early and post infectious complications affecting multiple systems. Though neurological sequelae including mononeuropathy, encephalopathy, transverse myelitis, polyradiculopathy, Guillain-Barre syndrome , optic neuropathy and oculomotor neuropathy have been reported in medical literature, the abducens nerve despite its notoriety in cranial neuropathies in a multitude of condition due to its long intracranial course had not been to date reported to manifest with lateral rectus paralysis following dengue. Case presentation A previously well 29 year old male with serologically confirmed dengue hemorrhagic fever developed symptomatic right lateral rectus palsy during the critical phase of the illness, which persisted into convalescence and post convalescence with proven deficit on Hess screen. Alternate etiologies were excluded by imaging, serology and electrophysiology. Conclusions The authors detail the first reported case of abducens nerve palsy complicating dengue fever in a previously healthy male from Sri Lanka. In a tropical country with endemic dengue infections, dengue related abducens neuropathy may be considered as a differential diagnosis in cases of acquired lateral rectus palsy after dengue fever. PMID:22799448

  14. Unilateral abducens and bilateral facial nerve palsies associated with posterior fossa exploration surgery

    PubMed Central

    Khalil, Ayman; Clerkin, James; Mandiwanza, Tafadzwa; Green, Sandra; Javadpour, Mohsen

    2016-01-01

    Multiple cranial nerves palsies following a posterior fossa exploration confined to an extradural compartment is a rare clinical presentation. This case report describes a young man who developed a unilateral abducens and bilateral facial nerve palsies following a posterior fossa exploration confined to an extradural compartment. There are different theories to explain this presentation, but the exact mechanism remains unclear. We propose that this patient cranial nerve palsies developed following cerebrospinal fluid (CSF) leak, potentially as a consequence of rapid change in CSF dynamics. PMID:26951144

  15. Unilateral abducens and bilateral facial nerve palsies associated with posterior fossa exploration surgery.

    PubMed

    Khalil, Ayman; Clerkin, James; Mandiwanza, Tafadzwa; Green, Sandra; Javadpour, Mohsen

    2016-03-06

    Multiple cranial nerves palsies following a posterior fossa exploration confined to an extradural compartment is a rare clinical presentation. This case report describes a young man who developed a unilateral abducens and bilateral facial nerve palsies following a posterior fossa exploration confined to an extradural compartment. There are different theories to explain this presentation, but the exact mechanism remains unclear. We propose that this patient cranial nerve palsies developed following cerebrospinal fluid (CSF) leak, potentially as a consequence of rapid change in CSF dynamics. Published by Oxford University Press and JSCR Publishing Ltd. All rights reserved. © The Author 2016.

  16. [Electromyographic differential diagnosis in cases of abducens nerve paresis with nuclear or distal neurogenic sive myogenic origine (author's transl)].

    PubMed

    Heuser, M

    1979-09-01

    Abducens nerve paresis may be of nuclear, of peripheral distal neurogenic origine, or is simulated by a myogenic weakness of abduction. Polygraphic emg analysis of the oculoauricularphenomenon (oap) permits a differentiation. In the emg, the oap proved to be a physiologic and constant automatic and always bilateral interaction between the hemolateral abducens nerve and both Nn. faciales with corresponding and obligatory coinnervation of the Mm. retroauricularis of the external ear. In case of medullary, nuclear or internuclear lesions, the oap is disturbed, instable, diminished or abolished, whereas in distal neurogenic or myogenic paresis, even in complete paralysis the oap is bilaterally well preserved.

  17. Postoperative full abduction in a patient of Duane retraction syndrome without an abducens nerve: a case report.

    PubMed

    Kim, Jae Hyoung; Hwang, Jeong-Min

    2017-05-19

    Duane retraction syndrome (DRS) consists of abduction deficit, globe retraction and upshoots or downshoots with adduction. The abducens nerve on the affected side is absent in type 1 DRS. After bilateral medial rectus muscle recession in unilateral type 1 DRS may improve the abduction limitation, but still more than -3 limitation remains. A 6-month-old boy presented with esotropia which had been noticed in early infancy. He showed limited abduction, fissure narrowing on attempted adduction and a small upshoot OS. Left abducens nerve was not identified on magnetic resonance imaging compatible with Duane retraction syndrome type 1. He showed full abduction after bilateral medial rectus recession of 6.0 mm at the age of 9 months, and remained orthotropia with full abduction OU 2 years postoperatively. He is my only patient with Duane retraction syndrome who showed full abduction after bilateral medial rectus recession. A patient with the type 1 Duane retraction syndrome rarely may show full abduction after bilateral medial rectus recession mimicking infantile esotropia.

  18. Usefulness of intraoperative electromyographic monitoring of oculomotor and abducens nerves during skull base surgery.

    PubMed

    Li, Zi-Yi; Li, Ming-Chu; Liang, Jian-Tao; Bao, Yu-Hai; Chen, Ge; Guo, Hong-Chuan; Ling, Feng

    2017-10-01

    Intraoperative neurophysiologic monitoring of the extraocular cranial nerve (EOCN) is not commonly performed because of technical difficulty and risk, reliability of the result and predictability of the postoperative function of the EOCN. We performed oculomotor nerve (CN III) and abducens nerve (CN VI) intraoperative monitoring in patients with skull base surgery by recording the spontaneous muscle activity (SMA) and compound muscle action potential (CMAP). Two types of needle electrodes of different length were percutaneously inserted into the extraocular muscles with the free-hand technique. We studied the relationships between the SMA and CMAP and postoperative function of CN III and CN VI. A total of 23 patients were included. Nineteen oculomotor nerves and 22 abducens nerves were monitored during surgery, respectively. Neurotonic discharge had a positive predictive value of less than 50% and negative predictive value of more than 80% for postoperative CN III and CN VI dysfunction. The latency of patients with postoperative CN III dysfunction was 2.79 ± 0.13 ms, longer than that with intact CN III function (1.73 ± 0.11 ms). One patient had transient CN VI dysfunction, whose CMAP latency (2.54 ms) was longer than that of intact CN VI function (2.11 ± 0.38 ms). There was no statistically significant difference between patients with paresis and with intact function. The method of intraoperative monitoring of EOCNs described here is safe and useful to record responses of SMA and CMAP. Neurotonic discharge seems to have limited value in predicting the postoperative function of CN III and CN VI. The onset latency of CMAP longer than 2.5 ms after tumor removal is probably relevant to postoperative CN III and CN VI dysfunction. However, a definite quantitative relationship has not been found between the amplitude and stimulation intensity of CMAP and the postoperative outcome of CN III and CN VI.

  19. Aberrant regeneration of the third cranial nerve.

    PubMed

    Shrestha, U D; Adhikari, S

    2012-01-01

    Aberrant regeneration of the third cranial nerve is most commonly due to its damage by trauma. A ten-month old child presented with the history of a fall from a four-storey building. She developed traumatic third nerve palsy and eventually the clinical features of aberrant regeneration of the third cranial nerve. The adduction of the eye improved over time. She was advised for patching for the strabismic amblyopia as well. Traumatic third nerve palsy may result in aberrant regeneration of the third cranial nerve. In younger patients, motility of the eye in different gazes may improve over time. © NEPjOPH.

  20. Measurement of wavefront aberrations in cortex and peripheral nerve using a two-photon excitation guidestar

    NASA Astrophysics Data System (ADS)

    Futia, Gregory L.; Fontaine, Arjun; McCullough, Connor; Ozbay, Baris N.; George, Nickolas M.; Caldwell, John; Restrepo, Diego; Weir, Richard; Gibson, Emily A.

    2018-02-01

    Neural-machine interfaces using optogenetics are of interest due to their minimal invasiveness and potential for parallel read in and read out of activity. One possible biological target for such an interface is the peripheral nerve, where axonlevel imaging or stimulation could greatly improve interfacing with artificial limbs or enable neuron/fascicle level neuromodulation in the vagus nerve. Two-photon imaging has been successful in imaging brain activity using genetically encoded calcium or voltage indicators, but in the peripheral nerve, this is severely limited by scattering and aberrations from myelin. We employ a Shack-Hartman wavefront sensor and two-photon excitation guidestar to quantify optical scattering and aberrations in peripheral nerves and cortex. The sciatic and vagus nerves, and cortex from a ChAT-Cre ChR-eYFP transgenic mouse were excised and imaged directly. In peripheral nerves, defocus was the strongest aberration followed by astigmatism and coma. Peripheral nerve had orders of magnitude higher aberration compared with cortex. These results point to the potential of adaptive optics for increasing the depth of two-photon access into peripheral nerves.

  1. Tumors Presenting as Multiple Cranial Nerve Palsies

    PubMed Central

    Kumar, Kishore; Ahmed, Rafeeq; Bajantri, Bharat; Singh, Amandeep; Abbas, Hafsa; Dejesus, Eddy; Khan, Rana Raheel; Niazi, Masooma; Chilimuri, Sridhar

    2017-01-01

    Cranial nerve palsy could be one of the presenting features of underlying benign or malignant tumors of the head and neck. The tumor can involve the cranial nerves by local compression, direct infiltration or by paraneoplastic process. Cranial nerve involvement depends on the anatomical course of the cranial nerve and the site of the tumor. Patients may present with single or multiple cranial nerve palsies. Multiple cranial nerve involvement could be sequential or discrete, unilateral or bilateral, painless or painful. The presentation could be acute, subacute or recurrent. Anatomic localization is the first step in the evaluation of these patients. The lesion could be in the brain stem, meninges, base of skull, extracranial or systemic disease itself. We present 3 cases of underlying neoplasms presenting as cranial nerve palsies: a case of glomus tumor presenting as cochlear, glossopharyngeal, vagus and hypoglossal nerve palsies, clivus tumor presenting as abducens nerve palsy, and diffuse large B-cell lymphoma presenting as oculomotor, trochlear, trigeminal and abducens nerve palsies due to paraneoplastic involvement. History and physical examination, imaging, autoantibodies and biopsy if feasible are useful for the diagnosis. Management outcomes depend on the treatment of the underlying tumor. PMID:28553221

  2. Behavior of accessory abducens and abducens motoneurons during eye retraction and rotation in the alert cat.

    PubMed

    Delgado-Garcia, J M; Evinger, C; Escudero, M; Baker, R

    1990-08-01

    1. The activity of both accessory abducens (Acc Abd) and abducens (Abd) motoneurons (Mns) was recorded in the alert cat during eye retraction and rotational eye movements. Cats were fitted with two scleral coils, one measured rotational eye movements directly and the other retraction by distinguishing the translational component. 2. Acc Abd and Abd Mns were identified following antidromic activation from electrical stimulation of the ipsilateral VIth nerve. 3. In response to corneal air puffs, bursts of spikes were produced in all (n = 30) Acc Abd Mns. The burst began 7.2 +/- 1.2 (SD) ms after onset of the air puff and 8.9 +/- 1.9 ms before eye retraction. 4. Acc Abd Mns were silent throughout all types of rotational eye movements, and tonic activity was not observed during intervals without air-puff stimulation. 5. In contrast, all (n = 50) identified Abd Mns exhibited a burst and/or pause in activity preceding and during horizontal saccades as well as a tonic activity proportional to eye position. 6. Only 10% of Abd Mns fired a weak burst of spikes in response to air-puff stimulation. 7. We conclude that Acc Abd Mns are exclusively involved in eye retraction in the cat and that only a few Abd Mns have an eye-retraction signal added to their eye position and velocity signals. Thus any rotational eye-movement response described in retractor bulbi muscle must result from innervation by Mns located in the Abd and/or the oculomotor nuclei. 8. The organization of the prenuclear circuitry and species variation are discussed in view of the nictiating membrane extension response measured in associative learning.

  3. Aberrant nerve fibres within the central nervous system.

    PubMed

    Moffie, D

    1992-01-01

    Three cases of aberrant nerve fibres in the spinal cord and medulla oblongata are described. The literature on these fibres is discussed and their possible role in regeneration. Different views on the possibility of regeneration or functional recovery of the central nervous system are mentioned in the light of recent publications, which are more optimistic than before.

  4. Electrophysiology of Extraocular Cranial Nerves: Oculomotor, Trochlear, and Abducens Nerve.

    PubMed

    Hariharan, Praveen; Balzer, Jeffery R; Anetakis, Katherine; Crammond, Donald J; Thirumala, Parthasarathy D

    2018-01-01

    The utility of extraocular cranial nerve electrophysiologic recordings lies primarily in the operating room during skull base surgeries. Surgical manipulation during skull base surgeries poses a risk of injury to multiple cranial nerves, including those innervating extraocular muscles. Because tumors distort normal anatomic relationships, it becomes particularly challenging to identify cranial nerve structures. Studies have reported the benefits of using intraoperative spontaneous electromyographic recordings and compound muscle action potentials evoked by electrical stimulation in preventing postoperative neurologic deficits. Apart from surgical applications, electromyography of extraocular muscles has also been used to guide botulinum toxin injections in patients with strabismus and as an adjuvant diagnostic test in myasthenia gravis. In this article, we briefly review the rationale, current available techniques to monitor extraocular cranial nerves, technical difficulties, clinical and surgical applications, as well as future directions for research.

  5. After facial nerve damage, regenerating axons become aberrant throughout the length of the nerve and not only at the site of the lesion: an experimental study.

    PubMed

    Choi, D; Raisman, G

    2004-02-01

    After facial nerve trauma, aberrant regeneration is associated with synkinesis. Animal models of mechanical nerve guides or reparative cell transplants at the site of a lesion have not been shown to improve disorganized regeneration. We examined whether this is because regenerating axons become disorganized throughout the length of the nerve and not only at the site of the lesion. In rats (n = 12), retrograde fluorescent tracer techniques were used to establish that most of the temporal branch fibres were carried in the superior half of the facial nerve trunk. In two further groups of rats (n = 24) a complete proximal facial nerve lesion was made, and the nerve immediately repaired by suture. After 4 weeks, at a second operation, the superior half of the facial nerve trunk was cut, either proximal or distal to the original lesion, and retrograde tracers were applied to distal branches of the nerve. It was possible to localize the points at which regenerating fibres became aberrant in their course by studying the number of labelled motoneurons in the facial nucleus after application of the tracer to the temporal branch of the nerve: this was similar in the distal and proximal hemisection groups, suggesting that aberrant axonal development occurred throughout the length of the nerve. Future strategies aimed at improving the organization of regeneration need to provide guidance cues not only at the site of the lesion as previously thought, but also throughout the length of the nerve.

  6. Aberrant gastrocnemius muscle innervation by tibial nerve afferents after implantation of chitosan tubes impregnated with progesterone favored locomotion recovery in rats with transected sciatic nerve.

    PubMed

    Sarabia-Estrada, Rachel; Bañuelos-Pineda, Jacinto; Osuna Carrasco, Laura P; Jiménez-Vallejo, Salvador; Jiménez-Estrada, Ismael; Rivas-Celis, Efrain; Dueñas-Jiménez, Judith M; Dueñas-Jiménez, Sergio H

    2015-07-01

    Transection of peripheral nerves produces loss of sensory and/or motor function. After complete nerve cutting, the distal and proximal segment ends retract, but if both ends are bridged with unaltered chitosan, progesterone-impregnated chitosan, or silicone tubes, an axonal repair process begins. Progesterone promotes nerve repair and has neuroprotective effects thwarting regulation of neuron survival, inflammation, and edema. It also modulates aberrant axonal sprouting and demyelination. The authors compared the efficacy of nerve recovery after implantation of progesterone-loaded chitosan, unaltered chitosan, or silicone tubes after sciatic nerve transection in rats. After surgical removal of a 5-mm segment of the proximal sciatic nerve, rats were implanted with progesterone-loaded chitosan, unaltered chitosan, or silicone tubes in the transected nerve for evaluating progesterone and chitosan effects on sciatic nerve repair and ipsilateral hindlimb kinematic function, as well as on gastrocnemius electro-myographic responses. In some experiments, tube implantation was performed 90 minutes after nerve transection. At 90 days after sciatic nerve transection and tube implantation, rats with progesterone-loaded chitosan tubes showed knee angular displacement recovery and better outcomes for step length, velocity of locomotion, and normal hindlimb raising above the ground. In contrast, rats with chitosan-only tubes showed reduced normal raising and pendulum-like hindlimb movements. Aberrant fibers coming from the tibial nerve innervated the gastrocnemius muscle, producing electromyographic responses. Electrical responses in the gastrocnemius muscle produced by sciatic nerve stimulation occurred only when the distal nerve segment was stimulated; they were absent when the proximal or intratubular segment was stimulated. A clear sciatic nerve morphology with some myelinated fiber fascicles appeared in the tube section in rats with progesterone-impregnated chitosan tubes

  7. Hepatocellular carcinoma metastasizing to the skull base involving multiple cranial nerves.

    PubMed

    Kim, Soo Ryang; Kanda, Fumio; Kobessho, Hiroshi; Sugimoto, Koji; Matsuoka, Toshiyuki; Kudo, Masatoshi; Hayashi, Yoshitake

    2006-11-07

    We describe a rare case of HCV-related recurrent multiple hepatocellular carcinoma (HCC) metastasizing to the skull base involving multiple cranial nerves in a 50-year-old woman. The patient presented with symptoms of ptosis, fixation of the right eyeball, and left abducens palsy, indicating disturbances of the right oculomotor and trochlear nerves and bilateral abducens nerves. Brain contrast-enhanced computed tomography (CT) revealed an ill-defined mass with abnormal enhancement around the sella turcica. Brain magnetic resonance imaging (MRI) disclosed that the mass involved the clivus, cavernous sinus, and petrous apex. On contrast-enhanced MRI with gadolinium-chelated contrast medium, the mass showed inhomogeneous intermediate enhancement. The diagnosis of metastatic HCC to the skull base was made on the basis of neurological findings and imaging studies including CT and MRI, without histological examinations. Further studies may provide insights into various methods for diagnosing HCC metastasizing to the craniospinal area.

  8. Isolated abducens nerve palsy associated with subarachnoid hemorrhage: a localizing sign of ruptured posterior inferior cerebellar artery aneurysms.

    PubMed

    Burkhardt, Jan-Karl; Winkler, Ethan A; Lasker, George F; Yue, John K; Lawton, Michael T

    2018-06-01

    OBJECTIVE Compressive cranial nerve syndromes can be useful bedside clues to the diagnosis of an enlarging intracranial aneurysm and can also guide subsequent evaluation, as with an acute oculomotor nerve (cranial nerve [CN] III) palsy that is presumed to be a posterior communicating artery aneurysm and a surgical emergency until proven otherwise. The CN VI has a short cisternal segment from the pontomedullary sulcus to Dorello's canal, remote from most PICA aneurysms but in the hemodynamic pathway of a rupturing PICA aneurysm that projects toward Dorello's canal. The authors describe a cranial nerve syndrome for posterior inferior cerebellar artery (PICA) aneurysms that associates subarachnoid hemorrhage (SAH) and an isolated abducens nerve (CN VI) palsy. METHODS Clinical and radiological data from 106 surgical patients with PICA aneurysms (66 ruptured and 40 unruptured) were retrospectively reviewed. Data from a group of 174 patients with other aneurysmal SAH (aSAH) were analyzed in a similar manner to control for nonspecific effects of SAH. Univariate statistical analysis compared incidence and risk factors associated with CN VI palsy in subarachnoid hemorrhage. RESULTS Overall, 13 (4.6%) of 280 patients had CN VI palsy at presentation, and all of them had ruptured aneurysms (representing 13 [5.4%] of the 240 cases of ruptured aneurysms). CN VI palsies were observed in 12 patients with ruptured PICA aneurysms (12/66 [18.1%]) and 1 patient with other aSAH (1/174 [0.1%], p < 0.0001). PICA aneurysm location in ruptured aneurysms was an independent predictor for CN VI palsy on multivariate analysis (p = 0.001). PICA aneurysm size was not significantly different in patients with or without CN VI palsy (average size 4.4 mm and 5.2 mm, respectively). Within the PICA aneurysm cohort, modified Fisher grade (p = 0.011) and presence of a thick cisternal SAH (modified Fisher Grades 3 and 4) (p = 0.003) were predictors of CN VI palsy. In all patients with ruptured PICA

  9. Does infantile abduction deficit indicate duane retraction syndrome until disproven?

    PubMed

    Kim, Jae Hyoung; Hwang, Jeong-Min

    2014-11-01

    Duane retraction syndrome consists of abduction deficit and palpebral fissure narrowing, upshoots, or downshoots on adduction. Infants with abduction deficit should be considered to have Duane retraction syndrome until disproven, because congenital abducens nerve palsy is extremely rare. The abducens nerve on the affected side is absent in type 1 Duane retraction syndrome and in some type 3 patients. The authors present a 7-month-old girl who showed limitation of abduction simulating Duane retraction syndrome. High-resolution magnetic resonance imaging (MRI) revealed atrophic lateral rectus and present abducens nerve. This report is important because this case showed that congenital abducens nerve palsy exists, although it is extremely rare, and high-resolution MRI could be pivotal for the differentiation of Duane retraction syndrome and congenital abducens nerve palsy in infancy. © The Author(s) 2014.

  10. Neurological Imaging in Acquired Cranial Nerve Palsy: Ophthalmologists vs. Neurologists.

    PubMed

    Klein Hesselink, Tessa; Gutter, Mari; Polling, Jan Roelof

    2017-09-01

    Cranial nerve palsies often require neurological imaging by MRI. Guidelines on whether or not to utilize MRI have been absent or lack clarity. In daily practice, both neurologists and ophthalmologists treat patients with cranial nerve palsy and determine whether neuro-imaging is required. There appear to be differences in policy with respect to neuro-imaging. The question, which will be answered in this study, is the following: to what extent do differences in policy exist between ophthalmologists and neurologists regarding imaging by MRI of patients with acquired ocular cranial nerve palsy? PubMed database was searched for literature on acquired cranial nerve palsy and MRI scanning performed by ophthalmologists and neurologists. Case series published between 2000 and 2015 were included. The first author screened the literature on eligibility, profession of the authors, and conducted data abstraction. Ten case series were found eligible for analysis. A total of 889 cranial nerve palsies were described, 770 by ophthalmologists and 119 by neurologists. The age range of patients in all case series was 2 to 96 years of age. The oculomotor nerve was investigated in 162 patients, the trochlear nerve in 131 patients, and the abducens nerve in 486 patients. All neurologists (n=3) and 2 out of 7 investigated ophthalmologists recommended performing MRI scanning in every patient who presented with an ocular cranial nerve palsy, while 5 ophthalmologists (5/7) opted to triage patients for risk factors associated with cranial nerve palsies prior to ordering MRI imaging. When different groups of patients were viewed separately, it became apparent that almost all specialists agreed that every patient with a third nerve palsy and patients under 50 years of age should undergo MRI scanning. In patients with fourth nerve palsy, MRI scanning was not indicated. The neurologists in this study were more likely to perform MRI scanning in every patient presenting with ocular cranial nerve

  11. [Depiction of the cranial nerves around the cavernous sinus by 3D reversed FISP with diffusion weighted imaging (3D PSIF-DWI)].

    PubMed

    Ishida, Go; Oishi, Makoto; Jinguji, Shinya; Yoneoka, Yuichiro; Sato, Mitsuya; Fujii, Yukihiko

    2011-10-01

    To evaluate the anatomy of cranial nerves running in and around the cavernous sinus, we employed three-dimensional reversed fast imaging with steady-state precession (FISP) with diffusion weighted imaging (3D PSIF-DWI) on 3-T magnetic resonance (MR) system. After determining the proper parameters to obtain sufficient resolution of 3D PSIF-DWI, we collected imaging data of 20-side cavernous regions in 10 normal subjects. 3D PSIF-DWI provided high contrast between the cranial nerves and other soft tissues, fluid, and blood in all subjects. We also created volume-rendered images of 3D PSIF-DWI and anatomically evaluated the reliability of visualizing optic, oculomotor, trochlear, trigeminal, and abducens nerves on 3D PSIF-DWI. All 20 sets of cranial nerves were visualized and 12 trochlear nerves and 6 abducens nerves were partially identified. We also presented preliminary clinical experiences in two cases with pituitary adenomas. The anatomical relationship between the tumor and cranial nerves running in and around the cavernous sinus could be three-dimensionally comprehended by 3D PSIF-DWI and the volume-rendered images. In conclusion, 3D PSIF-DWI has great potential to provide high resolution "cranial nerve imaging", which visualizes the whole length of the cranial nerves including the parts in the blood flow as in the cavernous sinus region.

  12. Cranial nerve injury after Le Fort I osteotomy.

    PubMed

    Kim, J-W; Chin, B-R; Park, H-S; Lee, S-H; Kwon, T-G

    2011-03-01

    A Le Fort I osteotomy is widely used to correct dentofacial deformity because it is a safe and reliable surgical method. Although rare, various complications have been reported in relation to pterygomaxillary separation. Cranial nerve damage is one of the serious complications that can occur after Le Fort I osteotomy. In this report, a 19-year-old man with unilateral cleft lip and palate underwent surgery to correct maxillary hypoplasia, asymmetry and mandibular prognathism. After the Le Fort I maxillary osteotomy, the patient showed multiple cranial nerve damage; an impairment of outward movement of the eye (abducens nerve), decreased vision (optic nerve), and paraesthesia of the frontal and upper cheek area (ophthalmic and maxillary nerve). The damage to the cranial nerve was related to an unexpected sphenoid bone fracture and subsequent trauma in the cavernous sinus during the pterygomaxillary osteotomy. Copyright © 2010 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  13. [Foster Modification of Full Tendon Transposition of Vertical Rectus Muscles for Sixth Nerve Palsy].

    PubMed

    Heede, Santa

    2018-04-11

    Since 1907 a variety of muscle transposition procedures for the treatment of abducens nerve palsy has been established internationally. Full tendon transposition of the vertical rectus muscle was initially described by O'Connor 1935 and then augmented by Foster 1997 with addition of posterior fixation sutures on the vertical rectus muscle. Full tendon transposition augmented by Foster belongs to the group of the most powerful surgical techniques to improve the abduction. Purpose of this study was to evaluate the results of full tendon vertical rectus transposition augmented with lateral fixation suture for patients with abducens nerve palsy. Full tendon transpositions of vertical rectus muscles augmented with posterior fixation suture was performed in 2014 on five patients with abducens nerve palsy. Two of the patients received Botox injections in the medial rectus muscle: one of them three months after the surgery and another during the surgery. One of the patients had a combined surgery of the horizontal muscles one year before. On three of the patients, who received a pure transposition surgery, the preoperative deviation at the distance (mean: + 56.6 pd; range: + 40 to + 80 pd) was reduced by a mean of 39.6 pd (range 34 to 50 pd), the abduction was improved by a mean of 3 mm (range 2 to 4 mm). The other two patients, who received besides the transposition procedure additional surgeries of the horizontal muscles, the preoperative deviation at the distance (+ 25 and + 126 pd respectively) was reduced by 20 and 81 pd respectively. The abduction was improved by 4 and 8 mm respectively. After surgery two patients developed a vertical deviation with a maximum of 4 pd. None of the patients had complications or signs of anterior segment ischemia. The elevation and/or depression was only marginally affected. There was no diplopia in up- or downgaze. Full tendon transposition of vertical rectus muscles, augmented with lateral posterior fixation suture is

  14. Anatomic and physiological characteristics of the ferret lateral rectus muscle and abducens nucleus.

    PubMed

    Bishop, Keith N; McClung, J Ross; Goldberg, Stephen J; Shall, Mary S

    2007-11-01

    The ferret has become a popular model for physiological and neurodevelopmental research in the visual system. We believed it important, therefore, to study extraocular whole muscle as well as single motor unit physiology in the ferret. Using extracellular stimulation, 62 individual motor units in the ferret abducens nucleus were evaluated for their contractile characteristics. Of these motor units, 56 innervated the lateral rectus (LR) muscle alone, while 6 were split between the LR and retractor bulbi (RB) muscle slips. In addition to individual motor units, the whole LR muscle was evaluated for twitch, tetanic peak force, and fatigue. The abducens nucleus motor units showed a twitch contraction time of 15.4 ms, a mean twitch tension of 30.2 mg, and an average fusion frequency of 154 Hz. Single-unit fatigue index averaged 0.634. Whole muscle twitch contraction time was 16.7 ms with a mean twitch tension of 3.32 g. The average fatigue index of whole muscle was 0.408. The abducens nucleus was examined with horseradish peroxidase conjugated with the subunit B of cholera toxin histochemistry and found to contain an average of 183 motoneurons. Samples of LR were found to contain an average of 4,687 fibers, indicating an LR innervation ratio of 25.6:1. Compared with cat and squirrel monkeys, the ferret LR motor units contract more slowly yet more powerfully. The functional visual requirements of the ferret may explain these fundamental differences.

  15. Motor palsies of cranial nerves (excluding VII) after vaccination: reports to the US Vaccine Adverse Event Reporting System.

    PubMed

    Woo, Emily Jane; Winiecki, Scott K; Ou, Alan C

    2014-01-01

    We reviewed cranial nerve palsies, other than VII, that have been reported to the US Vaccine Adverse Event Reporting System (VAERS). We examined patterns for differences in vaccine types, seriousness, age, and clinical characteristics. We identified 68 reports of cranial nerve palsies, most commonly involving the oculomotor (III), trochlear (IV), and abducens (VI) nerves. Isolated cranial nerve palsies, as well as palsies occurring as part of a broader clinical entity, were reported. Forty reports (59%) were classified as serious, suggesting that a cranial nerve palsy may sometimes be the harbinger of a broader and more ominous clinical entity, such as a stroke or encephalomyelitis. There was no conspicuous clustering of live vs. inactivated vaccines. The patient age range spanned the spectrum from infants to the elderly. Independent data may help to clarify whether, when, and to what extent the rates of cranial nerve palsies following particular vaccines may exceed background levels.

  16. [MRI in Duane retraction syndrome: Preliminary results].

    PubMed

    Denis, D; Cousin, M; Zanin, E; Toesca, E; Girard, N

    2011-09-01

    Duane retraction syndrome (DRS) is a congenital ocular motility disorder with innervational dysgenesis. MRI improves our understanding of this disease by providing in vivo access to nerves and oculomotor muscles. The goal of this prospective study (2000-2008) was to analyze DRS clinically and neuroradiologically. Twenty-four patients (27 eyes) received a complete ophthalmologic evaluation and a brain-orbital MRI. The average age was 6.1 years. MRI was performed with 3D T2 CISS-weighted images through the brainstem to visualize the cisternal segments of the cranial nerves and the orbit (lateral and medial recti muscles). MRI anomalies were classified according to type I, II, and III and depending on their condition in the posterior fossa (absence, hypoplasia) and in the orbit (muscle anomalies). Of 27 eyes, 70% were type I, 19% type II, and 11% type III. MRI showed abducens nerve abnormalities in 93% of the cases (78% absence) and muscle abnormalities in 57.5% of the cases. A detailed description showed 100% abducens nerve abnormalities and 58% abnormal lateral rectus muscle in type I, 60% abducens nerve abnormalities and 60% abnormal lateral rectus muscle in type II, and 100% abducens nerve abnormalities and 66% abnormal lateral rectus in type III. This study presents two major findings: detection of abducens nerve abnormalities in most cases of DRS whatever the type, associated with muscle abnormalities, and the confirmation that this absence may exist in type II (2/5). Thus MRI proved to be a valuable tool for investigating these patients, improving the comprehension of the physiopathogenics of this disease. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  17. Unusual Spread of Renal Cell Carcinoma to the Clivus with Cranial Nerve Deficit.

    PubMed

    Okudo, Jerome; Anusim, Nwabundo

    2016-01-01

    Renal cell carcinoma (RCC) has unusual presentation affecting elderly males with a smoking history. The incidence of RCC varies while the incidence of spread of RCC to the clivus is rare. The typicality of RCC presentation includes hematuria, flank pain, and a palpable flank mass; however, RCC can also present with clival metastasis. The unique path of the abducens nerve in the clivus makes it susceptible to damage in metastasis. We report a case of a 54-year-old African American female that was evaluated for back pain, weakness, numbness, and tingling of bilateral lower extremities and subsequently disconjugate gaze and diplopia. Brain MRI confirmed metastasis to the clivus. She was started on radiotherapy and was planned for chemotherapy and transfer to a nursing home. When a patient presents with sudden unusual cranial nerve pathology, the possibility of metastatic RCC should be sought.

  18. Stereotactic radiotherapy using Novalis for skull base metastases developing with cranial nerve symptoms.

    PubMed

    Mori, Yoshimasa; Hashizume, Chisa; Kobayashi, Tatsuya; Shibamoto, Yuta; Kosaki, Katsura; Nagai, Aiko

    2010-06-01

    Skull base metastases are challenging situations because they often involve critical structures such as cranial nerves. We evaluated the role of stereotactic radiotherapy (SRT) which can give high doses to the tumors sparing normal structures. We treated 11 cases of skull base metastases from other visceral carcinomas. They had neurological symptoms due to cranial nerve involvement including optic nerve (3 patients), oculomotor (3), trigeminal (6), abducens (1), facial (4), acoustic (1), and lower cranial nerves (1). The interval between the onset of cranial nerve symptoms and Novalis SRT was 1 week to 7 months. Eleven tumors of 8-112 ml in volume were treated by Novalis SRT with 30-50 Gy in 10-14 fractions. The tumors were covered by 90-95% isodose. Imaging and clinical follow-up has been obtained in all 11 patients for 5-36 months after SRT. Seven patients among 11 died from primary carcinoma or other visceral metastases 9-36 months after Novalis SRT. All 11 metastatic tumors were locally controlled until the end of the follow-up time or patient death, though retreatment for re-growth was done in 1 patient. In 10 of 11 patients, cranial nerve deficits were improved completely or partially. In some patients, the cranial nerve symptoms were relieved even during the period of fractionated SRT. Novalis SRT is thought to be safe and effective treatment for skull base metastases with involvement of cranial nerves and it may improve cranial nerve symptoms quickly.

  19. Skull Base Meningiomas and Cranial Nerves Contrast Using Sodium Fluorescein: A New Application of an Old Tool

    PubMed Central

    da Silva, Carlos Eduardo; da Silva, Vinicius Duval; da Silva, Jefferson Luis Braga

    2014-01-01

    Objective The identification of cranial nerves is one of the most challenging goals in the dissection of skull base meningiomas. The authors present an application of sodium fluorescein (SF) in skull base meningiomas with the purpose of improving the identification of cranial nerves. Design A prospective study within-subjects design. Setting Hospital Ernesto Dornelles, Porto Alegre, Brazil. Participants Patients with skull base meningiomas. Main Outcomes Measures Cranial nerve identification. Results The group of nine meningiomas was composed of one cavernous sinus, three petroclival, one tuberculum sellae, two sphenoid wing, one olfactory groove, and one temporal floor meningioma. The SF enhancement in all tumors was strong, and the contrast with cranial nerves clearly evident. There were one definite olfactory nerve deficit, one transient abducens deficit, and one definite hemiparesis. All lesions were resected (Simpson grades 1 and 2). The analysis of the difference of the delta SF wavelength between the meningiomas and cranial nerve contrast was performed by the Wilcoxon signed rank test and showed p = 0.011. Conclusions The contrast between the enhanced meningiomas and cranial nerves was evident and assisted in the visualization and microsurgical dissection of these structures. The anatomical preservation of these structures was improved using the contrast. PMID:27054056

  20. Skull Base Meningiomas and Cranial Nerves Contrast Using Sodium Fluorescein: A New Application of an Old Tool.

    PubMed

    da Silva, Carlos Eduardo; da Silva, Vinicius Duval; da Silva, Jefferson Luis Braga

    2014-08-01

    Objective The identification of cranial nerves is one of the most challenging goals in the dissection of skull base meningiomas. The authors present an application of sodium fluorescein (SF) in skull base meningiomas with the purpose of improving the identification of cranial nerves. Design A prospective study within-subjects design. Setting Hospital Ernesto Dornelles, Porto Alegre, Brazil. Participants Patients with skull base meningiomas. Main Outcomes Measures Cranial nerve identification. Results The group of nine meningiomas was composed of one cavernous sinus, three petroclival, one tuberculum sellae, two sphenoid wing, one olfactory groove, and one temporal floor meningioma. The SF enhancement in all tumors was strong, and the contrast with cranial nerves clearly evident. There were one definite olfactory nerve deficit, one transient abducens deficit, and one definite hemiparesis. All lesions were resected (Simpson grades 1 and 2). The analysis of the difference of the delta SF wavelength between the meningiomas and cranial nerve contrast was performed by the Wilcoxon signed rank test and showed p = 0.011. Conclusions The contrast between the enhanced meningiomas and cranial nerves was evident and assisted in the visualization and microsurgical dissection of these structures. The anatomical preservation of these structures was improved using the contrast.

  1. Peripheral nerve pathology, including aberrant Schwann cell differentiation, is ameliorated by doxycycline in a laminin-α2-deficient mouse model of congenital muscular dystrophy

    PubMed Central

    Homma, Sachiko; Beermann, Mary Lou; Miller, Jeffrey Boone

    2011-01-01

    The most common form of childhood congenital muscular dystrophy, Type 1A (MDC1A), is caused by mutations in the human LAMA2 gene that encodes the laminin-α2 subunit. In addition to skeletal muscle deficits, MDC1A patients typically show a loss of peripheral nerve function. To identify the mechanisms underlying this loss of nerve function, we have examined pathology and cell differentiation in sciatic nerves and ventral roots of the laminin-α2-deficient (Lama2−/−) mice, which are models for MDC1A. We found that, compared with wild-type, sciatic nerves of Lama2−/− mice had a significant increase in both proliferating (Ki67+) cells and premyelinating (Oct6+) Schwann cells, but also had a significant decrease in both immature/non-myelinating [glial fibrillary acidic protein (GFAP)+] and myelinating (Krox20+) Schwann cells. To extend our previous work in which we found that doxycycline, which has multiple effects on mammalian cells, improves motor behavior and more than doubles the median life-span of Lama2−/− mice, we also determined how nerve pathology was affected by doxycycline treatment. We found that myelinating (Krox20+) Schwann cells were significantly increased in doxycycline-treated compared with untreated sciatic nerves. In addition, doxycycline-treated peripheral nerves had significantly less pathology as measured by assays such as amount of unmyelinated or disorganized axons. This study thus identified aberrant proliferation and differentiation of Schwann cells as key components of pathogenesis in peripheral nerves and provided proof-of-concept that pharmaceutical therapy can be of potential benefit for peripheral nerve dysfunction in MDC1A. PMID:21505075

  2. Preoperative Visualization of Cranial Nerves in Skull Base Tumor Surgery Using Diffusion Tensor Imaging Technology.

    PubMed

    Ma, Jun; Su, Shaobo; Yue, Shuyuan; Zhao, Yan; Li, Yonggang; Chen, Xiaochen; Ma, Hui

    2016-01-01

    To visualize cranial nerves (CNs) using diffusion tensor imaging (DTI) with special parameters. This study also involved the evaluation of preoperative estimates and intraoperative confirmation of the relationship between nerves and tumor by verifying the accuracy of visualization. 3T magnetic resonance imaging scans including 3D-FSPGR, FIESTA, and DTI were used to collect information from 18 patients with skull base tumor. DTI data were integrated into the 3D slicer for fiber tracking and overlapped anatomic images to determine course of nerves. 3D reconstruction of tumors was achieved to perform neighboring, encasing, and invading relationship between lesion and nerves. Optic pathway including the optic chiasm could be traced in cases of tuberculum sellae meningioma and hypophysoma (pituitary tumor). The oculomotor nerve, from the interpeduncular fossa out of the brain stem to supraorbital fissure, was clearly visible in parasellar meningioma cases. Meanwhile, cisternal parts of trigeminal nerve and abducens nerve, facial nerve were also imaged well in vestibular schwannomas and petroclival meningioma cases. The 3D-spatial relationship between CNs and skull base tumor estimated preoperatively by tumor modeling and tractography corresponded to the results determined during surgery. Supported by DTI and 3D slicer, preoperative 3D reconstruction of most CNs related to skull base tumor is feasible in pathological circumstances. We consider DTI Technology to be a useful tool for predicting the course and location of most CNs, and syntopy between them and skull base tumor.

  3. Gradenigo's Syndrome in a Patient with Chronic Suppurative Otitis Media, Petrous Apicitis, and Meningitis.

    PubMed

    Taklalsingh, Nicholas; Falcone, Franco; Velayudhan, Vinodkumar

    2017-09-28

    BACKGROUND Gradenigo's syndrome includes the triad of suppurative otitis media, ipsilateral sixth (abducens) cranial nerve palsy and facial pain in the distribution of the fifth (trigeminal) cranial nerve. Gradenigo's syndrome is rare, and the diagnosis is easily overlooked. This case is the first to report Gradenigo's syndrome presenting with meningitis on a background of chronic suppurative otitis media (CSOM) and petrous apicitis (apical petrositis). CASE REPORT A 58-year-old male African American presented with headaches and confusion. Magnetic resonance imaging (MRI) of the head showed petrous apicitis with mastoiditis and abscess formation in the cerebellomedullary cistern (cisterna magna). The case was complicated by the development of palsy of the fourth (trochlear) cranial nerve, fifth (trigeminal) cranial nerve, and sixth (abducens) cranial nerve, with radiological changes indicating infection involving the seventh (facial) cranial nerve, and eighth (vestibulocochlear) cranial nerve. Cerebrospinal fluid (CSF) culture results were positive for Klebsiella pneumoniae, sensitive to ceftriaxone. The patient improved with surgery that included a left mastoidectomy and debridement of the petrous apex, followed by a ten-week course of antibiotics. Follow-up MRI showed resolution of the infection. CONCLUSIONS This report is of an atypical case of Gradenigo's syndrome. It is important to recognize that the classical triad of Gradenigo's syndrome, suppurative otitis media, ipsilateral sixth (abducens) cranial nerve palsy and facial pain in the distribution of the fifth (trigeminal) cranial nerve, may also involve chronic suppurative otitis media (CSOM), which may lead to involvement of other cranial nerves, petrous apicitis (apical petrositis), and bacterial meningitis.

  4. Medially placed vagus nerve in relation to common carotid artery: a pointer to a non-recurrent laryngeal nerve.

    PubMed

    Sagayaraj, A; Deo, Ravi Padmakar; Merchant, Shuaib; Mohiyuddin, S M Azeem; Nayak, Abhishek C

    2015-10-01

    The aim of this study was to highlight a medialized vagus in relation to common carotid artery as an operative marker to a non-recurrent laryngeal nerve during thyroid surgeries. Three patients who underwent thyroidectomy, in who per operative diagnosis of right non-recurrent laryngeal nerve was made and the findings were confirmed radiologically by demonstration of aberrant subclavian artery were included in the study. A medially placed vagus nerve in relation to common carotid artery was the common observation in all the 3 patients. With no operative marker to identify a non-recurrent laryngeal nerve, it is more prone to injury during thyroidectomies. Vagus nerve which was constantly seen medial to the common carotid artery in all our three patients can be used as an operative marker to a non-recurrent laryngeal nerve.

  5. Gradenigo’s Syndrome in a Patient with Chronic Suppurative Otitis Media, Petrous Apicitis, and Meningitis

    PubMed Central

    Taklalsingh, Nicholas; Falcone, Franco; Velayudhan, Vinodkumar

    2017-01-01

    Patient: Male, 58 Final Diagnosis: Bacterial meningitis Symptoms: Altered mental status • headache • neck stiffness • vomiting Medication: — Clinical Procedure: — Specialty: Infectious Diseases Objective: Rare disease Background: Gradenigo’s syndrome includes the triad of suppurative otitis media, ipsilateral sixth (abducens) cranial nerve palsy and facial pain in the distribution of the fifth (trigeminal) cranial nerve. Gradenigo’s syndrome is rare, and the diagnosis is easily overlooked. This case is the first to report Gradenigo’s syndrome presenting with meningitis on a background of chronic suppurative otitis media (CSOM) and petrous apicitis (apical petrositis). Case Report: A 58-year-old male African American presented with headaches and confusion. Magnetic resonance imaging (MRI) of the head showed petrous apicitis with mastoiditis and abscess formation in the cerebellomedullary cistern (cisterna magna). The case was complicated by the development of palsy of the fourth (trochlear) cranial nerve, fifth (trigeminal) cranial nerve, and sixth (abducens) cranial nerve, with radiological changes indicating infection involving the seventh (facial) cranial nerve, and eighth (vestibulocochlear) cranial nerve. Cerebrospinal fluid (CSF) culture results were positive for Klebsiella pneumoniae, sensitive to ceftriaxone. The patient improved with surgery that included a left mastoidectomy and debridement of the petrous apex, followed by a ten-week course of antibiotics. Follow-up MRI showed resolution of the infection. Conclusions: This report is of an atypical case of Gradenigo’s syndrome. It is important to recognize that the classical triad of Gradenigo’s syndrome, suppurative otitis media, ipsilateral sixth (abducens) cranial nerve palsy and facial pain in the distribution of the fifth (trigeminal) cranial nerve, may also involve chronic suppurative otitis media (CSOM), which may lead to involvement of other cranial nerves, petrous apicitis

  6. Pathological Location of Cranial Nerves in Petroclival Lesions: How to Avoid Their Injury during Anterior Petrosal Approach.

    PubMed

    Borghei-Razavi, Hamid; Tomio, Ryosuke; Fereshtehnejad, Seyed-Mohammad; Shibao, Shunsuke; Schick, Uta; Toda, Masahiro; Yoshida, Kazunari; Kawase, Takeshi

    2016-02-01

    Objectives  Numerous surgical approaches have been developed to access the petroclival region. The Kawase approach, through the middle fossa, is a well-described option for addressing cranial base lesions of the petroclival region. Our aim was to gather data about the variation of cranial nerve locations in diverse petroclival pathologies and clarify the most common pathologic variations confirmed during the anterior petrosal approach. Method  A retrospective analysis was made of both videos and operative and histologic records of 40 petroclival tumors from January 2009 to September 2013 in which the Kawase approach was used. The anatomical variations of cranial nerves IV-VI related to the tumor were divided into several location categories: superior lateral (SL), inferior lateral (IL), superior medial (SM), inferior medial (IM), and encased (E). These data were then analyzed taking into consideration pathologic subgroups of meningioma, epidermoid, and schwannoma. Results  In 41% of meningiomas, the trigeminal nerve is encased by the tumor. In 38% of the meningiomas, the trigeminal nerve is in the SL part of the tumor, and it is in 20% of the IL portion of the tumor. In 38% of the meningiomas, the trochlear nerve is encased by the tumor. The abducens nerve is not always visible (35%). The pathologic nerve pattern differs from that of meningiomas for epidermoid and trigeminal schwannomas. Conclusion  The pattern of cranial nerves IV-VI is linked to the type of petroclival tumor. In a meningioma, tumor origin (cavernous, upper clival, tentorial, and petrous apex) is the most important predictor of the location of cranial nerves IV-VI. Classification of four subtypes of petroclival meningiomas using magnetic resonance imaging is very useful to predict the location of deviated cranial nerves IV-VI intraoperatively.

  7. Motor nerve transplantation.

    PubMed

    Gray, W P; Keohane, C; Kirwan, W O

    1997-10-01

    The motor nerve transplantation (MNT) technique is used to transfer an intact nerve into a denervated muscle by harvesting a neurovascular pedicle of muscle containing motor endplates from the motor endplate zone of a donor muscle and implanting it into a denervated muscle. Thirty-six adult New Zealand White rabbits underwent reinnervation of the left long peroneal (LP) muscle (fast twitch) with a motor nerve graft from the soleus muscle (slow twitch). The right LP muscle served as a control. Reinnervation was assessed using microstimulatory single-fiber electromyography (SFEMG), alterations in muscle fiber typing and grouping, and isometric response curves. Neurofilament antibody was used for axon staining. The neurofilament studies provided direct evidence of nerve growth from the motor nerve graft into the adjacent denervated muscle. Median motor endplate jitter was 13 microsec preoperatively, and 26 microsec at 2 months, 29.5 microsec at 4 months, and 14 microsec at 6 months postoperatively (p < 0.001). Isometric tetanic tension studies showed a progressive functional recovery in the reinnervated muscle over 6 months. There was no histological evidence of aberrant reinnervation from any source outside the nerve pedicle. Isometric twitch responses and adenosine triphosphatase studies confirmed the conversion of the reinnervated LP muscle to a slow-type muscle. Acetylcholinesterase studies confirmed the presence of functioning motor endplates beneath the insertion of the motor nerve graft. It is concluded that the MNT technique achieves motor reinnervation by growth of new nerve fibers across the pedicle graft into the recipient muscle.

  8. Surgical repair of sciatic nerve traumatic rupture: technical considerations and approaches.

    PubMed

    Abou-Al-Shaar, Hussam; Yoon, Nam; Mahan, Mark A

    2018-01-01

    Traumatic proximal sciatic nerve rupture poses surgical repair dilemmas. Disruption often causes a large nerve gap after proximal neuroma and distal scar removal. Also, autologous graft material to bridge the segmental defect may be insufficient, given the sciatic nerve diameter. The authors utilized knee flexion to allow single neurorrhaphy repair of a large sciatic nerve defect, bringing healthy proximal stump to healthy distal segment. To avoid aberrant regeneration, the authors split the sciatic nerve into common peroneal and tibial divisions. After 3 months, the patient can fully extend the knee and has evidence of distal regeneration and nerve continuity without substantial injury. The video can be found here: https://youtu.be/lsezRT5I8MU .

  9. Limits to the capacity of transplants of olfactory glia to promote axonal regrowth in the CNS.

    PubMed

    Gudiño-Cabrera, G; Pastor, A M; de la Cruz, R R; Delgado-García, J M; Nieto-Sampedro, M

    2000-02-28

    Olfactory bulb ensheathing cell (OBEC) transplants promoted axonal regeneration in the spinal cord dorsal root entry zone and in the corticospinal tract. However, OBECs failed to promote abducens internuclear neuron axon regeneration when transplanted at the site of nerve fibre transection. In experiments performed in both cats and rats, OBECs survived for up to 2 months, lining themselves up along the portion of the regrowing axons proximal to the interneuron cell body. However, OBECs migrated preferentially towards abducens somata, in the direction opposite to the oculomotor nucleus target. OBECs seem to promote nerve fibre regeneration only where preferred direction of glial migration coincides with the direction of axonal growth towards its target.

  10. Surgical management of third nerve palsy

    PubMed Central

    Singh, Anupam; Bahuguna, Chirag; Nagpal, Ritu; Kumar, Barun

    2016-01-01

    Third nerve paralysis has been known to be associated with a wide spectrum of presentation and other associated factors such as the presence of ptosis, pupillary involvement, amblyopia, aberrant regeneration, poor bell's phenomenon, superior oblique (SO) overaction, and lateral rectus (LR) contracture. Correction of strabismus due to third nerve palsy can be complex as four out of the six extraocular muscles are involved and therefore should be approached differently. Third nerve palsy can be congenital or acquired. The common causes of isolated third nerve palsy in children are congenital (43%), trauma (20%), inflammation (13%), aneurysm (7%), and ophthalmoplegic migraine. Whereas, in adult population, common etiologies are vasculopathic disorders (diabetes mellitus, hypertension), aneurysm, and trauma. Treatment can be both nonsurgical and surgical. As nonsurgical modalities are not of much help, surgery remains the main-stay of treatment. Surgical strategies are different for complete and partial third nerve palsy. Surgery for complete third nerve palsy may involve supra-maximal recession - resection of the recti. This may be combined with SO transposition and augmented by surgery on the other eye. For partial third nerve, palsy surgery is determined according to nature and extent of involvement of extraocular muscles. PMID:27433033

  11. [Anatomicopathological relation between facial nerve and large vestibular Schwannoma].

    PubMed

    Jiang, T; Yu, C; Guo, E; Guan, S; Yan, C

    2001-05-10

    To study the anatomicopathological relation between facial nerve and large vestibular schwannoma. Operation by suboccipital retrosigmoid sinus approach was performed on 40 cases with large vestibular schwannoma, During the operation, the anatomicopathological relation between the facial nerve and the vestibular schwannoma was observed directly. The facial nerve was found to be located ventrally (deep under the tumor), dorsally (over the tumor), at the upper pole of the tumor (near the tentorium cerebelli), at the lower pole of the tumor (near the rear group cranial nerves), or aberrant (unable to be identified because of infiltration of tumor). In 31 cases, mainly with parenchymatous tumor, the facial nerve was flat in shape. In 9 cases, mainly with cystic tumor, the facial nerve was bandlike. The facial nerve varies greatly in neuroanatomy among patients with large vestibular schwannoma. Strengthening of operative monitoring can increase the safety of operation.

  12. Non-recurrent inferior laryngeal nerve identification during robotic thyroidectomy.

    PubMed

    Wang, C-C; Wu, C-H

    2014-02-01

    A non-recurrent inferior laryngeal nerve is a rare anomaly in which the nerve enters the larynx directly off the cervical vagus nerve, without descending to the thoracic level. It is very susceptible to damage during surgery. This report describes the important pre-operative radiological evaluations and surgical landmarks in a case of a non-recurrent inferior laryngeal nerve, identified during the recently developed technique of robotic thyroidectomy. A 38-year-old woman presented with suspected papillary microcarcinoma, as indicated by aspiration cytology. Pre-operative computed tomography showed a right aberrant subclavian artery that indicated a possible right non-recurrent inferior laryngeal nerve. Using robotic thyroidectomy methods, it was possible to carefully dissect along the thyroid capsule. The laryngeal entrance point of the right non-recurrent inferior laryngeal nerve (a constant anatomical landmark) was successfully identified via the three-dimensional, high-magnification views provided by the robotic endoscope. With proper knowledge of radiological and surgical anatomy, and the benefits of high-magnification endoscopic views, a non-recurrent inferior laryngeal nerve can be safely preserved during robotic surgery.

  13. Imaging of Cranial Nerves III, IV, VI in Congenital Cranial Dysinnervation Disorders

    PubMed Central

    Kim, Jae Hyoung

    2017-01-01

    Congenital cranial dysinnervation disorders are a group of diseases caused by abnormal development of cranial nerve nuclei or their axonal connections, resulting in aberrant innervation of the ocular and facial musculature. Its diagnosis could be facilitated by the development of high resolution thin-section magnetic resonance imaging. The purpose of this review is to describe the method to visualize cranial nerves III, IV, and VI and to present the imaging findings of congenital cranial dysinnervation disorders including congenital oculomotor nerve palsy, congenital trochlear nerve palsy, Duane retraction syndrome, Möbius syndrome, congenital fibrosis of the extraocular muscles, synergistic divergence, and synergistic convergence. PMID:28534340

  14. Imaging of Cranial Nerves III, IV, VI in Congenital Cranial Dysinnervation Disorders.

    PubMed

    Kim, Jae Hyoung; Hwang, Jeong Min

    2017-06-01

    Congenital cranial dysinnervation disorders are a group of diseases caused by abnormal development of cranial nerve nuclei or their axonal connections, resulting in aberrant innervation of the ocular and facial musculature. Its diagnosis could be facilitated by the development of high resolution thin-section magnetic resonance imaging. The purpose of this review is to describe the method to visualize cranial nerves III, IV, and VI and to present the imaging findings of congenital cranial dysinnervation disorders including congenital oculomotor nerve palsy, congenital trochlear nerve palsy, Duane retraction syndrome, Möbius syndrome, congenital fibrosis of the extraocular muscles, synergistic divergence, and synergistic convergence. © 2017 The Korean Ophthalmological Society.

  15. Sound-induced facial synkinesis following facial nerve paralysis.

    PubMed

    Ma, Ming-San; van der Hoeven, Johannes H; Nicolai, Jean-Philippe A; Meek, Marcel F

    2009-08-01

    Facial synkinesis (or synkinesia) (FS) occurs frequently after paresis or paralysis of the facial nerve and is in most cases due to aberrant regeneration of (branches of) the facial nerve. Patients suffer from inappropriate and involuntary synchronous facial muscle contractions. Here we describe two cases of sound-induced facial synkinesis (SFS) after facial nerve injury. As far as we know, this phenomenon has not been described in the English literature before. Patient A presented with right hemifacial palsy after lesion of the facial nerve due to skull base fracture. He reported involuntary muscle activity at the right corner of the mouth, specifically on hearing ringing keys. Patient B suffered from left hemifacial palsy following otitis media and developed involuntary muscle contraction in the facial musculature specifically on hearing clapping hands or a trumpet sound. Both patients were evaluated by means of video, audio and EMG analysis. Possible mechanisms in the pathophysiology of SFS are postulated and therapeutic options are discussed.

  16. Herpes zoster ophthalmicus and strabismus: a unique cause of secondary Brown syndrome.

    PubMed

    Broderick, Kevin M; Raymond, William R; Boden, John H

    2017-08-01

    Herpes zoster ophthalmicus can be associated with a variety of ocular and visual sequelae, including isolated or even multiple cranial neuropathies, potentially affecting the oculomotor, trochlear, or abducens nerves. We report a case of a secondary Brown syndrome following resolution of a unilateral isolated trochlear nerve palsy associated with herpes zoster ophthalmicus in an immunocompetent 57-year-old man. Published by Elsevier Inc.

  17. Optical aberrations, retinal image quality and eye growth: Experimentation and modeling

    NASA Astrophysics Data System (ADS)

    Tian, Yibin

    2007-12-01

    Retinal image quality is important for normal eye growth. Optical aberrations are of interest for two reasons: first, they degrade retinal images; second, they might provide some cues to defocus. Higher than normal ocular aberrations have been previously associated with human myopia. However, these studies were cross-sectional in design, and only reported aberrations in terms of root mean square (RMS) errors of Zernike coefficients, a poor metric of optical quality. This dissertation presents results from investigations of ocular optical aberrations, retinal image quality and eye growth in chicks and humans. A number of techniques were utilized, including Shack-Hartmann aberrometry, high-frequency A-scan ultrasonography, ciliary nerve section (CNX), photorefractive keratectomy (PRK) as well as computer simulations and modeling. A technique to extract light scatter information from Shack-Hartmann images was also developed. The main findings of the dissertation are summarized below. In young chicks, most ocular aberrations decreased with growth in both normal and CNX eyes, and there were diurnal fluctuations in some aberrations. Modeling suggested active reduction in higher order aberrations (HOAs) during early development. Although CNX eyes manifested greater than normal HOAs, they showed near normal growth. Retinal image degradation varied greatly among individual eyes post-PRK in young chicks. Including light scatter information into analyses of retinal image quality better estimated the latter. Albino eyes showed more severe retinal image degradation than normal eyes, due to increased optical aberrations and light scatter, but their growth was similar to those of normal eyes, implying that they are relatively insensitive to retina image quality. Although the above results questioned the influence of optical aberrations on early ocular growth, some optical quality metrics, derived from optical aberrations data, could predict how much the eyes of young chicks

  18. Potential Role of Semaphorin 3A and Its Receptors in Regulating Aberrant Sympathetic Innervation in Peritoneal and Deep Infiltrating Endometriosis

    PubMed Central

    Liang, Yanchun; Wang, Wei; Huang, Jiaming; Tan, Hao; Liu, Tianyu; Shang, Chunliang; Liu, Duo; Guo, Luyan; Yao, Shuzhong

    2015-01-01

    Previous studies have demonstrated the involvement of nerve repellent factors in regulation of the imbalanced innervation of endometriosis. This prospective study aims to explore the role of Sema 3A in regulating aberrant sympathetic innervation in peritoneal and deep infiltrating endometriosis. Ectopic endometriotic lesion were collected from patients with peritoneal endometriosis (n = 24) and deep infiltrating endometriosis of uterosacral ligament (n = 20) undergoing surgery for endometriosis. Eutopic endometrial samples were collected from patients with endometriosis (n = 22) or without endometriosis (n = 26). Healthy peritoneum (n = 13) from the lateral pelvic wall and healthy uterosacral ligament (n = 13) were obtained from patients who had no surgical and histological proof of endometriosis during hysterectomy for uterine fibroids. Firstly, we studied the immunostaining of Sema 3A, Plexin A1 and NRP-1 in all the tissues described above. Then we studied the nerve fiber density (NFD) of endometriosis-associated (sympathetic) nerve and para-endometriotic (sympathetic) nerve by double immunofluorescence staining. Finally we analyzed the relationship between expression of Sema 3A in stromal cells of endometriotic lesion and the aberrant innervation of endometriosis. Semi-quantitative immunostaining demonstrated that (1) Higher immunostaining of Sema 3A were found in the eutopic endometrial glandular epithelial cells from patients with endometriosis (p = 0.041) than those without endometriosis; (2) Sema 3A immunostaining was higher in glandular epithelial cells of peritoneal endometriosis (P<0.001) and deep infiltrating endometriotic lesions of uterosacral ligament (P = 0.028)compared with glandular epithelial cells of the endometrium from women with endometriosis, while its expression in ectopic stormal cells in both groups were significantly lower than that from eutopic endometrium of women without endometirosis (P<0.001, P<0.001, respectively). NFDs of Anti

  19. Understanding the extraocular muscles and oculomotor, trochlear, and abducens nerves through a simulation in physical examination training: an innovative approach.

    PubMed

    Zhang, Niu; He, Xiaohua

    2010-01-01

    The purpose of this study was to investigate the effect of an innovative exhibitory eye model simulation in a physical examination laboratory format on explaining Listing's Law concerning the individual extraocular muscle action and the rationale for cranial nerve testing. Participants were 71 volunteers in the third quarter of a chiropractic training program. The study involved a specially designed eyeball model used to explain the movements of individual extraocular muscles based on Listing's law and their cranial innervations in conjunction with the physical examination. Pre- and post-written tests were used to assess participants' understanding of the subjects taught. The test results were compared with those of nonparticipants who also took the same pre- and posttests. An independent samples t-test of the posttest showed a significant difference between the groups. The study group students achieved higher scores than their counterparts in the control group. Using an innovative approach to explain Listing's law and rationale for cranial nerve tests can improve physical examination skill and help produce more effective written test results.

  20. Anatomical study of the opossum (Didelphis albiventris) extraocular muscles.

    PubMed Central

    Matheus, S M; Soares, J C; da Silva, A M; Seullner, G

    1995-01-01

    The anatomy of the extraocular muscles was studied in 10 adult opossums (Didelphis albiventris) of both sexes. Eight extraocular muscles were identified: 4 rectus muscles, 2 oblique muscles, the levator palpebrae superioris and the retractor ocular bulbi. The rectus muscles originate very close one to another between the orbital surfaces of the presphenoid and palatine bones. These muscles diverge on the way to their insertion which occurs at about 2 mm from the limbus. The levator palpebrae superioris originates with the dorsal rectus and is positioned dorsally in relation to it. The retractor ocular bulbi forms a cone which embraces the optic nerve and is located internally in relation to the rectus muscles. The dorsal oblique originates on the presphenoid bone and after a tendinous trajectory through a trochlea on the medial wall of the orbit, inserts into the ocular bulb. The only muscle arising from the anterior orbital floor is the ventral oblique. The main nerve supply for these muscles is the oculomotor, except for the dorsal oblique which is innervated by the trochlear nerve, and the lateral rectus which is innervated by the abducens nerve. The retractor ocular bulbi receives branches from the inferior division of the oculomotor nerve and some branches from the abducens nerve. Images Fig. 1 Fig. 2 Fig. 3 PMID:7649843

  1. Accessory branch of median nerve supplying the brachialis muscle: a case report and clinical significance.

    PubMed

    Paraskevas, George; Anastasopoulos, Nikolaos; Nitsa, Zoi; Kitsoulis, Panagiotis; Spyridakis, Ioannis

    2014-12-01

    A very rare case of an accessory branch of the median nerve taking its origin in the region of the right arm was observed to supply the infero-medial portion of the brachialis muscle in a male cadaver. Simultaneously, the ipsilateral musculocutaneous nerve was innervating the muscles of the anterior compartment of the arm. Such an aberrant muscular branch of the median nerve for the brachialis muscle is very rarely reported in the literature. Lesion of the median nerve proximal to the branch's origin site could induce weak flexion of the elbow, whereas injury of the musculocutaneous nerve could lead to misinterpretation of symptoms. We discuss the patterns of brachialis muscle innervation as well as the clinical applications of such a variant.

  2. Two unusual anatomic variations create a diagnostic dilemma in distal ulnar nerve compression.

    PubMed

    Kiehn, Mark W; Derrick, Allison J; Iskandar, Bermans J

    2008-09-01

    Diagnosis of peripheral neuropathies is based upon patterns of functional deficits and electrodiagnostic testing. However, anatomic variations can lead to confounding patterns of physical and electrodiagnostic findings. Authors present a case of ulnar nerve compression due to a rare combination of anatomic variations, aberrant branching pattern, and FCU insertion at the wrist, which posed a diagnostic and therapeutic dilemma. The literature related to isolated distal ulnar motor neuropathy and anatomic variations of the ulnar nerve and adjacent structures is also reviewed. This case demonstrates how anatomic variations can complicate the interpretation of clinical and electrodiagnostic findings and underscores the importance of thorough exploration of the nerve in consideration for possible variations. (c) 2008 Wiley-Liss, Inc.

  3. Managing the patient with oculomotor nerve palsy.

    PubMed

    Sadagopan, Karthikeyan A; Wasserman, Barry N

    2013-09-01

    To provide clinically relevant information regarding the evaluation and current treatment options for oculomotor nerve palsies. We survey recent literature and provide some insights into these studies. Recent case reports highlight emerging new causes of oculomotor cranial nerve palsies, including sellar chordoma, odontogenic abscess, nonaneurysmal subarachnoid hemorrhage, polycythemia, sphenoiditis, neurobrucellosis, interpeduncular fossa lipoma, metastatic pancreatic cancer, leukemia, and lymphoma. Surgical studies have focused on modifications and innovations regarding strabismus surgery for this condition. New globe fixation procedures may include fixation to the medial orbital wall by precaruncular and retrocaruncular approaches, apically based orbital bone periosteal flap fixation and the suture/T-plate anchoring platform system. Management of oculomotor nerve palsy depends in part upon the underlying cause and anatomical location of the lesion. Careful clinical evaluation and appropriate imaging can identify a definitive cause in most cases. Surgical options depend on the number, extent, and severity of the muscles involved as well as the presence or absence of signs of aberrant regeneration. The clinician should also address issues that arise due to involvement of the pupil and accommodation. Strabismus surgery can be challenging but also rewarding with appropriate selection and staging of procedures.

  4. Ophthalmologic outcome after third cranial nerve palsy or paresis in childhood.

    PubMed

    Mudgil, A V; Repka, M X

    1999-02-01

    The purpose of this study was to evaluate the causes and ophthalmologic outcome of oculomotor nerve palsy or paresis in children younger than 8 years of age. Patients evaluated between 1985 and 1997 were retrospectively reviewed. Data analyzed included vision, residual strabismus after surgery, aberrant reinnervation, binocular function, and anisometropia. Long-term outcome was assessed in patients followed-up longer than 6 months. Forty-one patients were identified. The most frequent causes were congenital (39%), traumatic (37%), and neoplastic (17%). Visual acuities were reduced in 71% of patients at the time of the initial visit. Long-term outcome could be assessed in 20 of the 41 patients (49%), with a mean follow-up of 3.6 years (range, 0.5 to 13 years). Visual acuities were reduced because of amblyopia in 35% and nonamblyopic factors in 25% of patients in the long-term outcome group at last follow-up. The best response to amblyopia therapy was in the congenital group, in which all patients improved to normal visual acuity. Strabismus surgery was performed on 8 of 20 children (40%) followed-up, none of whom demonstrated measurable stereopsis after operation despite improved alignment. Aberrant reinnervation was present in 9 of 20 patients (45%). Only 3 patients fully recovered from their oculomotor nerve injuries, and these were the only patients to regain measurable stereopsis. The causes in those 3 patients were congenital, traumatic, and neoplastic. Oculomotor nerve palsy/paresis is associated with poor visual and sensorimotor outcome in children younger than 8 years of age. The best ophthalmologic outcome was in the resolved cases (3 of 20; 15%). Amblyopia therapy was most effective with congenital causes, but treatment results were poor with other causes. Young children with posttraumatic and postneoplastic oculomotor nerve injuries demonstrated the worst ophthalmologic outcomes.

  5. [Effect of abducens orthosis combined with walker on developmental dysplasia of the hip].

    PubMed

    Hu, Zhiyong; Xu, Yongqiang; Liang, Jieyu; Li, Kanghua; Liao, Qiande

    2009-07-01

    To evaluate the effect of abducens orthosis combined with walker on developmental dysplasia of the hip (DDH). A total of 126 patients (224 hips) with DDH aged 6-36 months in Xiangya Hospital was randomly divided into 2 groups: an orthosis combined with walker group and an improved hip frog cast fixation group. Seventy patients (130 hips) were treated by the orthosis combined with walker and 56 patients (94 hips) were treated by the improved hip frog cast fixation. We compared the effect and complications of the 2 groups. The fineness rates of the orthosis combined with walker group and the improved hip frog cast fixation group were 89.2% and 90.4%, respectively, with no significant difference (P>0.05). The rate of femoral head osteonecrosis in the orthosis combined with walker group was significantly lower than that in the improved hip frog cast fixation group (1.5% vs. 5.3%,P<0.05), but the re-dislocation rate in the former was significantly higher than that in the latter (6.9% vs. 1.1 %, P<0.05). Both methods are effective for DDH. Orthosis combined with walker has a lower proportion of femoral head osteonecrosis, but a higher proportion of re-dislocation.

  6. Aberrant ATRX protein expression is associated with poor overall survival in NF1-MPNST

    PubMed Central

    Lu, Hsiang-Chih; Eulo, Vanessa; Apicelli, Anthony J.; Pekmezci, Melike; Tao, Yu; Luo, Jingqin; Hirbe, Angela C.; Dahiya, Sonika

    2018-01-01

    Malignant Peripheral Nerve Sheath Tumors (MPNSTs) are aggressive soft tissue sarcomas that can occur sporadically or in the setting of the Neurofibromatosis type 1 (NF1) cancer predisposition syndrome. These tumors carry a dismal overall survival. Previous work in our lab had identified ATRX chromatin remodeler (ATRX), previously termed, Alpha Thalassemia/Mental Retardation Syndrome X Linked as a gene mutated in a subset of MPNSTs. Given the great need for novel biomarkers and therapeutic targets for MPNSTs, we sought to determine the expression of ATRX in a larger subset of sporadic and NF1 associated MPNSTs (NF1-MPNSTs). We performed immunohistochemistry (IHC) on 74 MPNSTs (43 NF1-associated and 31 sporadic), 21 plexiform neurofibromas, and 9 atypical neurofibromas. Using this approach, we have demonstrated that 58% (43/74) of MPNSTs have aberrant ATRX expression (<80% nuclear expression) compared to only 7% (2/30) of benign (plexiform and atypical) neurofibromas. Second, we demonstrated that 65% (28/43) of NF1-MPNSTs displayed aberrant ATRX expression as did 48% (15/31) of sporadic MPNSTs. Finally, we show that aberrant ATRX expression was associated with a significantly decreased overall survival for patients with NF1-MPNST (median OS of 17.9 months for aberrant expression and median OS not met (>120 months) for intact expression, p = 0.0276). In summary, we demonstrate that ATRX is aberrantly expressed in the majority of NF1-MPNSTs, but not plexiform or atypical neurofibromas. Additionally, aberrant ATRX expression is associated with decreased overall survival in NF1-MPNST, but not sporadic MPNST and may serve as a prognostic marker for patients with NF1-MPNST. PMID:29796169

  7. The Non-Recurrent Laryngeal Nerve: a meta-analysis and clinical considerations

    PubMed Central

    Sanna, Silvia; Graves, Matthew J.; Vikse, Jens; Sanna, Beatrice; Tomaszewska, Iwona M.; Tubbs, R. Shane; Walocha, Jerzy A.; Tomaszewski, Krzysztof A.

    2017-01-01

    Background The Non-Recurrent Laryngeal Nerve (NRLN) is a rare embryologically-derived variant of the Recurrent Laryngeal Nerve (RLN). The presence of an NRLN significantly increases the risk of iatrogenic injury and operative complications. Our aim was to provide a comprehensive meta-analysis of the overall prevalence of the NRLN, its origin, and its association with an aberrant subclavian artery. Methods Through March 2016, a database search was performed of PubMed, CNKI, ScienceDirect, EMBASE, BIOSIS, SciELO, and Web of Science. The references in the included articles were also extensively searched. At least two reviewers judged eligibility and assessed and extracted articles. MetaXL was used for analysis, with all pooled prevalence rates calculated using a random effects model. Heterogeneity among the included studies was assessed using the Chi2 test and the I2 statistic. Results Fifty-three studies (33,571 right RLNs) reported data on the prevalence of a right NRLN. The pooled prevalence estimate was 0.7% (95% CI [0.6–0.9]). The NRLN was found to originate from the vagus nerve at or above the laryngotracheal junction in 58.3% and below it in 41.7%. A right NRLN was associated with an aberrant subclavian artery in 86.7% of cases. Conclusion The NRLN is a rare yet very clinically relevant structure for surgeons and is associated with increased risk of iatrogenic injury, most often leading to temporary or permanent vocal cord paralysis. A thorough understanding of the prevalence, origin, and associated pathologies is vital for preventing injuries and complications. PMID:28344898

  8. Determination of aberration center of Ronchigram for automated aberration correctors in scanning transmission electron microscopy.

    PubMed

    Sannomiya, Takumi; Sawada, Hidetaka; Nakamichi, Tomohiro; Hosokawa, Fumio; Nakamura, Yoshio; Tanishiro, Yasumasa; Takayanagi, Kunio

    2013-12-01

    A generic method to determine the aberration center is established, which can be utilized for aberration calculation and axis alignment for aberration corrected electron microscopes. In this method, decentering induced secondary aberrations from inherent primary aberrations are minimized to find the appropriate axis center. The fitness function to find the optimal decentering vector for the axis was defined as a sum of decentering induced secondary aberrations with properly distributed weight values according to the aberration order. Since the appropriate decentering vector is determined from the aberration values calculated at an arbitrary center axis, only one aberration measurement is in principle required to find the center, resulting in /very fast center search. This approach was tested for the Ronchigram based aberration calculation method for aberration corrected scanning transmission electron microscopy. Both in simulation and in experiments, the center search was confirmed to work well although the convergence to find the best axis becomes slower with larger primary aberrations. Such aberration center determination is expected to fully automatize the aberration correction procedures, which used to require pre-alignment of experienced users. This approach is also applicable to automated aperture positioning. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Granulocyte colony-stimulating factor off-target effect on nerve outgrowth promotes prostate cancer development.

    PubMed

    Dobrenis, Kostantin; Gauthier, Laurent R; Barroca, Vilma; Magnon, Claire

    2015-02-15

    The hematopoietic growth factor granulocyte colony-stimulating factor (G-CSF) has a role in proliferation, differentiation and migration of the myeloid lineage and in mobilizing hematopoietic stem and progenitor cells into the bloodstream. However, G-CSF has been newly characterized as a neurotrophic factor in the brain. We recently uncovered that autonomic nerve development in the tumor microenvironment participates actively in prostate tumorigenesis and metastasis. Here, we found that G-CSF constrains cancer to grow and progress by, respectively, supporting the survival of sympathetic nerve fibers in 6-hydroxydopamine-sympathectomized mice and also, promoting the aberrant outgrowth of parasympathetic nerves in transgenic or xenogeneic prostate tumor models. This provides insight into how neurotrophic growth factors may control tumor neurogenesis and may lead to new antineurogenic therapies for prostate cancer. © 2014 UICC.

  10. Moebius syndrome with Dandy-Walker variant and agenesis of corpus callosum.

    PubMed

    John, Jomol Sara; Vanitha, R

    2013-09-01

    Moebius syndrome is a rare congenital neurological disorder. The most frequent mode of presentation is facial diplegia with bilateral lateral rectus palsy, but there are variations. Here, we report a rare case of Moebius syndrome in a 15-month-old child with unilateral facial palsy, bilateral abducens nerve palsy with Dandy Walker variant, and complete agenesis of corpus callosum.

  11. Interpreting Chromosome Aberration Spectra

    NASA Technical Reports Server (NTRS)

    Levy, Dan; Reeder, Christopher; Loucas, Bradford; Hlatky, Lynn; Chen, Allen; Cornforth, Michael; Sachs, Rainer

    2007-01-01

    Ionizing radiation can damage cells by breaking both strands of DNA in multiple locations, essentially cutting chromosomes into pieces. The cell has enzymatic mechanisms to repair such breaks; however, these mechanisms are imperfect and, in an exchange process, may produce a large-scale rearrangement of the genome, called a chromosome aberration. Chromosome aberrations are important in killing cells, during carcinogenesis, in characterizing repair/misrepair pathways, in retrospective radiation biodosimetry, and in a number of other ways. DNA staining techniques such as mFISH ( multicolor fluorescent in situ hybridization) provide a means for analyzing aberration spectra by examining observed final patterns. Unfortunately, an mFISH observed final pattern often does not uniquely determine the underlying exchange process. Further, resolution limitations in the painting protocol sometimes lead to apparently incomplete final patterns. We here describe an algorithm for systematically finding exchange processes consistent with any observed final pattern. This algorithm uses aberration multigraphs, a mathematical formalism that links the various aspects of aberration formation. By applying a measure to the space of consistent multigraphs, we will show how to generate model-specific distributions of aberration processes from mFISH experimental data. The approach is implemented by software freely available over the internet. As a sample application, we apply these algorithms to an aberration data set, obtaining a distribution of exchange cycle sizes, which serves to measure aberration complexity. Estimating complexity, in turn, helps indicate how damaging the aberrations are and may facilitate identification of radiation type in retrospective biodosimetry.

  12. Moebius syndrome with Dandy-Walker variant and agenesis of corpus callosum

    PubMed Central

    John, Jomol Sara; Vanitha, R.

    2013-01-01

    Moebius syndrome is a rare congenital neurological disorder. The most frequent mode of presentation is facial diplegia with bilateral lateral rectus palsy, but there are variations. Here, we report a rare case of Moebius syndrome in a 15-month-old child with unilateral facial palsy, bilateral abducens nerve palsy with Dandy Walker variant, and complete agenesis of corpus callosum. PMID:24470815

  13. Role of the vagus nerve in the development and treatment of diet‐induced obesity

    PubMed Central

    2016-01-01

    Abstract This review highlights evidence for a role of the vagus nerve in the development of obesity and how targeting the vagus nerve with neuromodulation or pharmacology can be used as a therapeutic treatment of obesity. The vagus nerve innervating the gut plays an important role in controlling metabolism. It communicates peripheral information about the volume and type of nutrients between the gut and the brain. Depending on the nutritional status, vagal afferent neurons express two different neurochemical phenotypes that can inhibit or stimulate food intake. Chronic ingestion of calorie‐rich diets reduces sensitivity of vagal afferent neurons to peripheral signals and their constitutive expression of orexigenic receptors and neuropeptides. This disruption of vagal afferent signalling is sufficient to drive hyperphagia and obesity. Furthermore neuromodulation of the vagus nerve can be used in the treatment of obesity. Although the mechanisms are poorly understood, vagal nerve stimulation prevents weight gain in response to a high‐fat diet. In small clinical studies, in patients with depression or epilepsy, vagal nerve stimulation has been demonstrated to promote weight loss. Vagal blockade, which inhibits the vagus nerve, results in significant weight loss. Vagal blockade is proposed to inhibit aberrant orexigenic signals arising in obesity as a putative mechanism of vagal blockade‐induced weight loss. Approaches and molecular targets to develop future pharmacotherapy targeted to the vagus nerve for the treatment of obesity are proposed. In conclusion there is strong evidence that the vagus nerve is involved in the development of obesity and it is proving to be an attractive target for the treatment of obesity. PMID:26959077

  14. Hypoglossal-facial nerve reconstruction using a Y-tube-conduit reduces aberrant synkinetic movements of the orbicularis oculi and vibrissal muscles in rats.

    PubMed

    Kaya, Yasemin; Ozsoy, Umut; Turhan, Murat; Angelov, Doychin N; Sarikcioglu, Levent

    2014-01-01

    The facial nerve is the most frequently damaged nerve in head and neck trauma. Patients undergoing facial nerve reconstruction often complain about disturbing abnormal synkinetic movements of the facial muscles (mass movements, synkinesis) which are thought to result from misguided collateral branching of regenerating motor axons and reinnervation of inappropriate muscles. Here, we examined whether use of an aorta Y-tube conduit during reconstructive surgery after facial nerve injury reduces synkinesis of orbicularis oris (blink reflex) and vibrissal (whisking) musculature. The abdominal aorta plus its bifurcation was harvested (N = 12) for Y-tube conduits. Animal groups comprised intact animals (Group 1), those receiving hypoglossal-facial nerve end-to-end coaptation alone (HFA; Group 2), and those receiving hypoglossal-facial nerve reconstruction using a Y-tube (HFA-Y-tube, Group 3). Videotape motion analysis at 4 months showed that HFA-Y-tube group showed a reduced synkinesis of eyelid and whisker movements compared to HFA alone.

  15. Hypoglossal-Facial Nerve Reconstruction Using a Y-Tube-Conduit Reduces Aberrant Synkinetic Movements of the Orbicularis Oculi and Vibrissal Muscles in Rats

    PubMed Central

    Kaya, Yasemin; Ozsoy, Umut; Turhan, Murat; Angelov, Doychin N.; Sarikcioglu, Levent

    2014-01-01

    The facial nerve is the most frequently damaged nerve in head and neck trauma. Patients undergoing facial nerve reconstruction often complain about disturbing abnormal synkinetic movements of the facial muscles (mass movements, synkinesis) which are thought to result from misguided collateral branching of regenerating motor axons and reinnervation of inappropriate muscles. Here, we examined whether use of an aorta Y-tube conduit during reconstructive surgery after facial nerve injury reduces synkinesis of orbicularis oris (blink reflex) and vibrissal (whisking) musculature. The abdominal aorta plus its bifurcation was harvested (N = 12) for Y-tube conduits. Animal groups comprised intact animals (Group 1), those receiving hypoglossal-facial nerve end-to-end coaptation alone (HFA; Group 2), and those receiving hypoglossal-facial nerve reconstruction using a Y-tube (HFA-Y-tube, Group 3). Videotape motion analysis at 4 months showed that HFA-Y-tube group showed a reduced synkinesis of eyelid and whisker movements compared to HFA alone. PMID:25574468

  16. Nerve stripper-assisted sural nerve harvest.

    PubMed

    Hassanpour, Esmail; Yavari, Masoud; Karbalaeikhani, Ali; Saremi, Hossein

    2014-03-01

    Sural nerve has the favorite length and size for nerve graft interposition. Here two techniques, that is, "stocking seam" and "stair-step" or "stepladder," have been used for harvesting sural nerve. The first technique results in an unsightly scar at the posterior calf, and the latter one takes a long time to perform and exert undue traction to the graft during harvesting. The purpose of this article is to describe our experience in harvesting the sural nerve by a nerve stripper. A nerve stripper was used for harvesting sural nerve in 35 adult patients (in 6 patients, sural harvesting was done bilaterally), 27 men and 8 women. Thirty-one sural nerve harvests were done by closed technique (i.e., harvesting of sural nerve only by two incisions, one in the posterior of the lateral malleolus and the other in popliteal fossa), in 8 others by limited open technique, and in 2 cases, there was early laceration of the sural nerve at the beginning of the study. The contralateral sural nerve was harvested in one patient and medial antebrachial nerve in another by open technique. The mean length of the retrieved sural nerve was 34.5 cm in the closed technique group and 35 cm in the limited open technique group. We detected advancing Tinel's sign in all nerve stripper-assisted sural nerve harvested group members in both the closed and limited open groups. Sural nerve harvesting by the nerve stripper is a reliable and simple technique, and it is applicable as a routine technique. Applying controlled rotatory movements of the nerve stripper instead of pushing can result in satisfactory harvesting of the sural nerve without early laceration. Georg Thieme Verlag KG Stuttgart · New York.

  17. Afferent fibers and sensory ganglion cells within the oculomotor nerve in some mammals and man. II. Electrophysiological investigations.

    PubMed

    Manni, E; Bortolami, R; Pettorossi, V E; Lucchi, M L; Callegari, E

    1978-01-01

    The main aim of the present study was to localize with electrophysiological techniques the central projections and terminations of the aberrant trigeminal fibres contained in the oculomotor nerve of the lamb. After severing a trigeminal root, single-shock electrical stimulation of the trigeminal axons present in the central stump of the ipsilateral oculomotor nerve evoked field potentials in the area of, i) the subnucleus gelatinosus of the nucleus caudalis trigemini at the level of C1-C2; ii) the main sensory trigeminal nucleus; iii) the descending trigeminal nucleus and tract; iv) the adjacent reticular formation. Units whose discharge rate was influenced by such a stimulation were also found in the same territories. These regions actually exhibited degenerations after cutting an oculomotor nerve. We conclude, therefore, that the trigeminal fibres which leave the Vth nerve at the level of the cavernous sinus and enter the brain stem through the IIIrd nerve, end in the same structures which receive the terminations of the afferent fibres entering the brain stem through the sensory trigeminal root.

  18. Mask-induced aberration in EUV lithography

    NASA Astrophysics Data System (ADS)

    Nakajima, Yumi; Sato, Takashi; Inanami, Ryoichi; Nakasugi, Tetsuro; Higashiki, Tatsuhiko

    2009-04-01

    We estimated aberrations using Zernike sensitivity analysis. We found the difference of the tolerated aberration with line direction for illumination. The tolerated aberration of perpendicular line for illumination is much smaller than that of parallel line. We consider this difference to be attributable to the mask 3D effect. We call it mask-induced aberration. In the case of the perpendicular line for illumination, there was a difference in CD between right line and left line without aberration. In this report, we discuss the possibility of pattern formation in NA 0.25 generation EUV lithography tool. In perpendicular pattern for EUV light, the dominant part of aberration is mask-induced aberration. In EUV lithography, pattern correction based on the mask topography effect will be more important.

  19. [Sural nerve removal using a nerve stripper].

    PubMed

    Assmus, H

    1983-03-01

    In 19 patients the sural nerve was removed for nerve grafting by a specially designed nerve stripper. This technique provides a safe and time-saving removal of the nerve in length up to 34 cm (depending on the length of the stripper used). From a single short incision at the level of the lateral malleolus the nerve is stripped proximally tearing some small branches of the distal nerve. The relatively blunt tip avoids inadvertent transection of the nerve at a lower level or dissection of the nerve at a point where branching occurs. Finally the nerve is cut by the divided cylinder at the tip of the stripper.

  20. Camera processing with chromatic aberration.

    PubMed

    Korneliussen, Jan Tore; Hirakawa, Keigo

    2014-10-01

    Since the refractive index of materials commonly used for lens depends on the wavelengths of light, practical camera optics fail to converge light to a single point on an image plane. Known as chromatic aberration, this phenomenon distorts image details by introducing magnification error, defocus blur, and color fringes. Though achromatic and apochromatic lens designs reduce chromatic aberration to a degree, they are complex and expensive and they do not offer a perfect correction. In this paper, we propose a new postcapture processing scheme designed to overcome these problems computationally. Specifically, the proposed solution is comprised of chromatic aberration-tolerant demosaicking algorithm and post-demosaicking chromatic aberration correction. Experiments with simulated and real sensor data verify that the chromatic aberration is effectively corrected.

  1. End-to-side neurorrhaphy repairs peripheral nerve injury: sensory nerve induces motor nerve regeneration.

    PubMed

    Yu, Qing; Zhang, She-Hong; Wang, Tao; Peng, Feng; Han, Dong; Gu, Yu-Dong

    2017-10-01

    End-to-side neurorrhaphy is an option in the treatment of the long segment defects of a nerve. It involves suturing the distal stump of the disconnected nerve (recipient nerve) to the side of the intimate adjacent nerve (donor nerve). However, the motor-sensory specificity after end-to-side neurorrhaphy remains unclear. This study sought to evaluate whether cutaneous sensory nerve regeneration induces motor nerves after end-to-side neurorrhaphy. Thirty rats were randomized into three groups: (1) end-to-side neurorrhaphy using the ulnar nerve (mixed sensory and motor) as the donor nerve and the cutaneous antebrachii medialis nerve as the recipient nerve; (2) the sham group: ulnar nerve and cutaneous antebrachii medialis nerve were just exposed; and (3) the transected nerve group: cutaneous antebrachii medialis nerve was transected and the stumps were turned over and tied. At 5 months, acetylcholinesterase staining results showed that 34% ± 16% of the myelinated axons were stained in the end-to-side group, and none of the myelinated axons were stained in either the sham or transected nerve groups. Retrograde fluorescent tracing of spinal motor neurons and dorsal root ganglion showed the proportion of motor neurons from the cutaneous antebrachii medialis nerve of the end-to-side group was 21% ± 5%. In contrast, no motor neurons from the cutaneous antebrachii medialis nerve of the sham group and transected nerve group were found in the spinal cord segment. These results confirmed that motor neuron regeneration occurred after cutaneous nerve end-to-side neurorrhaphy.

  2. End-to-side neurorrhaphy repairs peripheral nerve injury: sensory nerve induces motor nerve regeneration

    PubMed Central

    Yu, Qing; Zhang, She-hong; Wang, Tao; Peng, Feng; Han, Dong; Gu, Yu-dong

    2017-01-01

    End-to-side neurorrhaphy is an option in the treatment of the long segment defects of a nerve. It involves suturing the distal stump of the disconnected nerve (recipient nerve) to the side of the intimate adjacent nerve (donor nerve). However, the motor-sensory specificity after end-to-side neurorrhaphy remains unclear. This study sought to evaluate whether cutaneous sensory nerve regeneration induces motor nerves after end-to-side neurorrhaphy. Thirty rats were randomized into three groups: (1) end-to-side neurorrhaphy using the ulnar nerve (mixed sensory and motor) as the donor nerve and the cutaneous antebrachii medialis nerve as the recipient nerve; (2) the sham group: ulnar nerve and cutaneous antebrachii medialis nerve were just exposed; and (3) the transected nerve group: cutaneous antebrachii medialis nerve was transected and the stumps were turned over and tied. At 5 months, acetylcholinesterase staining results showed that 34% ± 16% of the myelinated axons were stained in the end-to-side group, and none of the myelinated axons were stained in either the sham or transected nerve groups. Retrograde fluorescent tracing of spinal motor neurons and dorsal root ganglion showed the proportion of motor neurons from the cutaneous antebrachii medialis nerve of the end-to-side group was 21% ± 5%. In contrast, no motor neurons from the cutaneous antebrachii medialis nerve of the sham group and transected nerve group were found in the spinal cord segment. These results confirmed that motor neuron regeneration occurred after cutaneous nerve end-to-side neurorrhaphy. PMID:29171436

  3. Neuro-ophthalmological approach to facial nerve palsy.

    PubMed

    Portelinha, Joana; Passarinho, Maria Picoto; Costa, João Marques

    2015-01-01

    Facial nerve palsy is associated with significant morbidity and can have different etiologies. The most common causes are Bell's palsy, Ramsay-Hunt syndrome and trauma, including surgical trauma. Incidence varies between 17 and 35 cases per 100,000. Initial evaluation should include accurate clinical history, followed by a comprehensive investigation of the head and neck, including ophthalmological, otological, oral and neurological examination, to exclude secondary causes. Routine laboratory testing and diagnostic imaging is not indicated in patients with new-onset Bell's palsy, but should be performed in patients with risk factors, atypical cases or in any case without resolution within 4 months. Many factors are involved in determining the appropriate treatment of these patients: the underlying cause, expected duration of nerve dysfunction, anatomical manifestations, severity of symptoms and objective clinical findings. Systemic steroids should be offered to patients with new-onset Bell's palsy to increase the chance of facial nerve recovery and reduce synkinesis. Ophthalmologists play a pivotal role in the multidisciplinary team involved in the evaluation and rehabilitation of these patients. In the acute phase, the main priority should be to ensure adequate corneal protection. Treatment depends on the degree of nerve lesion and on the risk of the corneal damage based on the amount of lagophthalmos, the quality of Bell's phenomenon, the presence or absence of corneal sensitivity and the degree of lid retraction. The main therapy is intensive lubrication. Other treatments include: taping the eyelid overnight, botulinum toxin injection, tarsorrhaphy, eyelid weight implants, scleral contact lenses and palpebral spring. Once the cornea is protected, longer term planning for eyelid and facial rehabilitation may take place. Spontaneous complete recovery of Bell's palsy occurs in up to 70% of cases. Long-term complications include aberrant regeneration with

  4. Neuro-ophthalmological approach to facial nerve palsy

    PubMed Central

    Portelinha, Joana; Passarinho, Maria Picoto; Costa, João Marques

    2014-01-01

    Facial nerve palsy is associated with significant morbidity and can have different etiologies. The most common causes are Bell’s palsy, Ramsay–Hunt syndrome and trauma, including surgical trauma. Incidence varies between 17 and 35 cases per 100,000. Initial evaluation should include accurate clinical history, followed by a comprehensive investigation of the head and neck, including ophthalmological, otological, oral and neurological examination, to exclude secondary causes. Routine laboratory testing and diagnostic imaging is not indicated in patients with new-onset Bell’s palsy, but should be performed in patients with risk factors, atypical cases or in any case without resolution within 4 months. Many factors are involved in determining the appropriate treatment of these patients: the underlying cause, expected duration of nerve dysfunction, anatomical manifestations, severity of symptoms and objective clinical findings. Systemic steroids should be offered to patients with new-onset Bell’s palsy to increase the chance of facial nerve recovery and reduce synkinesis. Ophthalmologists play a pivotal role in the multidisciplinary team involved in the evaluation and rehabilitation of these patients. In the acute phase, the main priority should be to ensure adequate corneal protection. Treatment depends on the degree of nerve lesion and on the risk of the corneal damage based on the amount of lagophthalmos, the quality of Bell’s phenomenon, the presence or absence of corneal sensitivity and the degree of lid retraction. The main therapy is intensive lubrication. Other treatments include: taping the eyelid overnight, botulinum toxin injection, tarsorrhaphy, eyelid weight implants, scleral contact lenses and palpebral spring. Once the cornea is protected, longer term planning for eyelid and facial rehabilitation may take place. Spontaneous complete recovery of Bell’s palsy occurs in up to 70% of cases. Long-term complications include aberrant regeneration

  5. [Oculo-auricular phenomenon and its value in neurologic diagnosis].

    PubMed

    Wagner, A; Röder, H; Pöschel, E; Mundt, B

    1984-09-01

    The oculoauricular phenomenon is a synergism between an external eye muscle, the m. rectus lateralis, and the facialis innervated m. retroauricularis. In the neurological diagnostic this phenomenon permits a differentiation between the abducens nerve paresis of peripheral and of nuclear origine. In addition to this electromyographic examination from the m. retroauricularis can discover disturbances of the neuromuscular transmission and facilitate an early prognostic estimation of peripheral facialis paresis.

  6. Preoperative computed tomography diagnosis of non-recurrent laryngeal nerve in patients with esophageal carcinoma.

    PubMed

    Niu, Zhong-Xi; Zhang, Hang; Chen, Long-Qi; Shi, Hui; Peng, Jun; Su, Li-Wei; Li, Wei; Xiao, Bo; He, Shu; Yue, Hong-Xu

    2017-01-01

    The non-recurrent laryngeal nerve (NRLN) is a rare but potentially serious anomaly that is commonly associated with the aberrant right subclavian artery (ARSA). It is easy to damage during surgical resection of esophageal cancer, leading to severe complications. Preoperative enhanced thoracic computed tomography (CT) scans of 2697 patients with esophageal carcinoma treated in our hospital between January 2010 and December 2013 were examined. We classified the positional relationship between the right subclavian artery and the membranous wall of the trachea into two types and used this method to predicate NRLN by identifying ARSA. Twenty-six patients (0.96%) were identified with ARSA, all of which were cases of NRLN by CT. NRLN was identified during surgery in the 26 patients, and a normal right recurrent laryngeal nerve was observed in 2671 patients. The ARSA was detected on the dorsal side of the membranous wall of the trachea in all 26 NRLN cases, while it was detected on the ventral side in all 2671 recurrent laryngeal nerve cases. Enhanced CT scanning is a reliable method for predicting NRLN by identifying ARSA. Preoperative recognition of this nerve anomaly allows surgeons to avoid damaging the nerve and abnormal vessels during esophagectomy. © 2016 The Authors. Thoracic Cancer published by China Lung Oncology Group and John Wiley & Sons Australia, Ltd.

  7. Neuregulin-1 signaling is essential for nerve-dependent axolotl limb regeneration.

    PubMed

    Farkas, Johanna E; Freitas, Polina D; Bryant, Donald M; Whited, Jessica L; Monaghan, James R

    2016-08-01

    The Mexican axolotl (Ambystoma mexicanum) is capable of fully regenerating amputated limbs, but denervation of the limb inhibits the formation of the post-injury proliferative mass called the blastema. The molecular basis behind this phenomenon remains poorly understood, but previous studies have suggested that nerves support regeneration via the secretion of essential growth-promoting factors. An essential nerve-derived factor must be found in the blastema, capable of rescuing regeneration in denervated limbs, and its inhibition must prevent regeneration. Here, we show that the neuronally secreted protein Neuregulin-1 (NRG1) fulfills all these criteria in the axolotl. Immunohistochemistry and in situ hybridization of NRG1 and its active receptor ErbB2 revealed that they are expressed in regenerating blastemas but lost upon denervation. NRG1 was localized to the wound epithelium prior to blastema formation and was later strongly expressed in proliferating blastemal cells. Supplementation by implantation of NRG1-soaked beads rescued regeneration to digits in denervated limbs, and pharmacological inhibition of NRG1 signaling reduced cell proliferation, blocked blastema formation and induced aberrant collagen deposition in fully innervated limbs. Taken together, our results show that nerve-dependent NRG1/ErbB2 signaling promotes blastemal proliferation in the regenerating limb and may play an essential role in blastema formation, thus providing insight into the longstanding question of why nerves are required for axolotl limb regeneration. © 2016. Published by The Company of Biologists Ltd.

  8. Correlations between corneal and total wavefront aberrations

    NASA Astrophysics Data System (ADS)

    Mrochen, Michael; Jankov, Mirko; Bueeler, Michael; Seiler, Theo

    2002-06-01

    Purpose: Corneal topography data expressed as corneal aberrations are frequently used to report corneal laser surgery results. However, the optical image quality at the retina depends on all optical elements of the eye such as the human lens. Thus, the aim of this study was to investigate the correlations between the corneal and total wavefront aberrations and to discuss the importance of corneal aberrations for representing corneal laser surgery results. Methods: Thirty three eyes of 22 myopic subjects were measured with a corneal topography system and a Tschernig-type wavefront analyzer after the pupils were dilated to at least 6 mm in diameter. All measurements were centered with respect to the line of sight. Corneal and total wavefront aberrations were calculated up to the 6th Zernike order in the same reference plane. Results: Statistically significant correlations (p < 0.05) between the corneal and total wavefront aberrations were found for the astigmatism (C3,C5) and all 3rd Zernike order coefficients such as coma (C7,C8). No statistically significant correlations were found for all 4th to 6th order Zernike coefficients except for the 5th order horizontal coma C18 (p equals 0.003). On average, all Zernike coefficients for the corneal aberrations were found to be larger compared to Zernike coefficients for the total wavefront aberrations. Conclusions: Corneal aberrations are only of limited use for representing the optical quality of the human eye after corneal laser surgery. This is due to the lack of correlation between corneal and total wavefront aberrations in most of the higher order aberrations. Besides this, the data present in this study yield towards an aberration balancing between corneal aberrations and the optical elements within the eye that reduces the aberration from the cornea by a certain degree. Consequently, ideal customized ablations have to take both, corneal and total wavefront aberrations, into consideration.

  9. OF TRYPANOSOMATIDS. ENDOTRANSFORMATIONS AND ABERRATIONS].

    PubMed

    Frolov, A O; Malysheva, M N; Kostygov, A Yu

    2016-01-01

    Endotransformations and aberrations of the life cycle in the evolutionary history of trypanosomatids (Kinetoplastea: Trypanosomatidae) are analyzed. We treat the term "endotransformations" as evolutionarily fixed changes of phases and/or developmental stages of parasites. By contrast, we treat aberrations as evolutionary unstable, periodically arising deformations of developmental phases of trypanosomatids, never leading to life cycle changes. Various examples of life cycle endotransformations and aberrations in representatives of the family Trypanosomatidae are discussed.

  10. Eye movements and abducens motoneuron behavior after cholinergic activation of the nucleus reticularis pontis caudalis.

    PubMed

    Márquez-Ruiz, Javier; Escudero, Miguel

    2010-11-01

    the aim of this work was to characterize eye movements and abducens (ABD) motoneuron behavior after cholinergic activation of the nucleus reticularis pontis caudalis (NRPC). six female adult cats were prepared for chronic recording of eye movements (using the scleral search-coil technique), electroencephalography, electromyography, ponto-geniculo-occipital (PGO) waves in the lateral geniculate nucleus, and ABD motoneuron activities after microinjections of the cholinergic agonist carbachol into the NRPC. unilateral microinjections of carbachol in the NRPC induced tonic and phasic phenomena in the oculomotor system. Tonic effects consisted of ipsiversive rotation to the injected side, convergence, and downward rotation of the eyes. Phasic effects consisted of bursts of rhythmic rapid eye movements directed contralaterally to the injected side along with PGO-like waves in the lateral geniculate and ABD nuclei. Although tonic effects were dependent on the level of drowsiness, phasic effects were always present and appeared along with normal saccades when the animal was vigilant. ABD motoneurons showed phasic activities associated with ABD PGO-like waves during bursts of rapid eye movements, and tonic and phasic activities related to eye position and velocity during alertness. the cholinergic activation of the NRPC induces oculomotor phenomena that are somewhat similar to those described during REM sleep. A precise comparison of the dynamics and timing of the eye movements further suggests that a temporal organization of both NRPCs is needed to reproduce the complexity of the oculomotor behavior during REM sleep.

  11. Effects of nerve cells and adhesion molecules on nerve conduit for peripheral nerve regeneration

    PubMed Central

    Fiorellini, Joseph P.

    2017-01-01

    Background For peripheral nerve regeneration, recent attentions have been paid to the nerve conduits made by tissue-engineering technique. Three major elements of tissue-engineering are cells, molecules, and scaffolds. Methods In this study, the attachments of nerve cells, including Schwann cells, on the nerve conduit and the effects of both growth factor and adhesion molecule on these attachments were investigated. Results The attachment of rapidly-proliferating cells, C6 cells and HS683 cells, on nerve conduit was better than that of slowly-proliferating cells, PC12 cells and Schwann cells, however, the treatment of nerve growth factor improved the attachment of slowly-proliferating cells. In addition, the attachment of Schwann cells on nerve conduit coated with fibronectin was as good as that of Schwann cells treated with glial cell line-derived neurotrophic factor (GDNF). Conclusions Growth factor changes nerve cell morphology and affects cell cycle time. And nerve growth factor or fibronectin treatment is indispensable for Schwann cell to be used for implantation in artificial nerve conduits. PMID:29090249

  12. Monochromatic ocular wave aberrations in young monkeys

    PubMed Central

    Ramamirtham, Ramkumar; Kee, Chea-su; Hung, Li-Fang; Qiao-Grider, Ying; Roorda, Austin; Smith, Earl L.

    2006-01-01

    High-order monochromatic aberrations could potentially influence vision-dependent refractive development in a variety of ways. As a first step in understanding the effects of wave aberration on refractive development, we characterized the maturational changes that take place in the high-order aberrations of infant rhesus monkey eyes. Specifically, we compared the monochromatic wave aberrations of infant and adolescent animals and measured the longitudinal changes in the high-order aberrations of infant monkeys during the early period when emmetropization takes place. Our main findings were that (1) adolescent monkey eyes have excellent optical quality, exhibiting total RMS errors that were slightly better than those for adult human eyes that have the same numerical aperture and (2) shortly after birth, infant rhesus monkeys exhibited relatively larger magnitudes of high-order aberrations predominately spherical aberration, coma, and trefoil, which decreased rapidly to assume adolescent values by about 200 days of age. The results demonstrate that rhesus monkey eyes are a good model for studying the contribution of individual ocular components to the eye’s overall aberration structure, the mechanisms responsible for the improvements in optical quality that occur during early ocular development, and the effects of high-order aberrations on ocular growth and emmetropization. PMID:16750549

  13. Iteration of ultrasound aberration correction methods

    NASA Astrophysics Data System (ADS)

    Maasoey, Svein-Erik; Angelsen, Bjoern; Varslot, Trond

    2004-05-01

    Aberration in ultrasound medical imaging is usually modeled by time-delay and amplitude variations concentrated on the transmitting/receiving array. This filter process is here denoted a TDA filter. The TDA filter is an approximation to the physical aberration process, which occurs over an extended part of the human body wall. Estimation of the TDA filter, and performing correction on transmit and receive, has proven difficult. It has yet to be shown that this method works adequately for severe aberration. Estimation of the TDA filter can be iterated by retransmitting a corrected signal and re-estimate until a convergence criterion is fulfilled (adaptive imaging). Two methods for estimating time-delay and amplitude variations in receive signals from random scatterers have been developed. One method correlates each element signal with a reference signal. The other method use eigenvalue decomposition of the receive cross-spectrum matrix, based upon a receive energy-maximizing criterion. Simulations of iterating aberration correction with a TDA filter have been investigated to study its convergence properties. A weak and strong human-body wall model generated aberration. Both emulated the human abdominal wall. Results after iteration improve aberration correction substantially, and both estimation methods converge, even for the case of strong aberration.

  14. Neck ultrasonography for detection of non-recurrent laryngeal nerve

    PubMed Central

    Citton, Marilisa; Viel, Giovanni

    2016-01-01

    Background Non-recurrent laryngeal nerve (NRLN) is a rare anatomical variant (0.3–6%) that is associated with some arterial abnormalities (absence of the brachiocephalic trunk and presence of a right aberrant subclavian lusorian artery). The availability of a preoperative diagnosis of NRLN may reduce the risk of nerve injuries. Preoperative ultrasonography (US) has been suggested as a reliable diagnostic tool to detect the arterial abnormalities associated with NRLN, but the literature is relatively scarce. This paper was aimed to review the literature, in order to offer an up to-date on this technique and its results. Methods A web search, focusing on humans, was performed by PubMed database, including papers published up to August 2016, using the key words “ultrasonography” AND “non-recurrent laryngeal nerve” or “nonrecurrent laryngeal nerve”. Results Eight papers, including 3,740 patients who underwent neck US for the detection of NRLN were selected. Only five studies focused on the preoperative use of US. The incidence of NRLN varied between 0.4% and 1.94%. The sensitivity and specificity varied between 99–100% and 41–100%, respectively. Conclusions US is a simple, non-invasive and cost-effective method to detect NRLN, also if its accuracy is not absolute. It may be used preoperatively and to prevent the intraoperative nerve damage, since the risk of NRLN palsies is significantly reduced when a preoperative diagnosis is available. PMID:28149804

  15. Raman spectroscopic detection of peripheral nerves towards nerve-sparing surgery

    NASA Astrophysics Data System (ADS)

    Minamikawa, Takeo; Harada, Yoshinori; Takamatsu, Tetsuro

    2017-02-01

    The peripheral nervous system plays an important role in motility, sensory, and autonomic functions of the human body. Preservation of peripheral nerves in surgery, namely nerve-sparing surgery, is now promising technique to avoid functional deficits of the limbs and organs following surgery as an aspect of the improvement of quality of life of patients. Detection of peripheral nerves including myelinated and unmyelinated nerves is required for the nerve-sparing surgery; however, conventional nerve identification scheme is sometimes difficult to identify peripheral nerves due to similarity of shape and color to non-nerve tissues or its limited application to only motor peripheral nerves. To overcome these issues, we proposed a label-free detection technique of peripheral nerves by means of Raman spectroscopy. We found several fingerprints of peripheral myelinated and unmyelinated nerves by employing a modified principal component analysis of typical spectra including myelinated nerve, unmyelinated nerve, and adjacent tissues. We finally realized the sensitivity of 94.2% and the selectivity of 92.0% for peripheral nerves including myelinated and unmyelinated nerves against adjacent tissues. Although further development of an intraoperative Raman spectroscopy system is required for clinical use, our proposed approach will serve as a unique and powerful tool for peripheral nerve detection for nerve-sparing surgery in the future.

  16. [Monochromatic aberration in accommodation. Dynamic wavefront analysis].

    PubMed

    Fritzsch, M; Dawczynski, J; Jurkutat, S; Vollandt, R; Strobel, J

    2011-06-01

    Monochromatic aberrations may influence the visual acuity of the eye. They are not stable and can be affected by different factors. The subject of the following paper is the dynamic investigation of the changes in wavefront aberration with accommodation. Dynamic measurement of higher and lower order aberrations was performed with a WASCA Wavefront Analyzer (Carl-Zeiss-Meditec) and a specially constructed target device for aligning objects in far and near distances on 25 subjects aged from 15 to 27 years old. Wavefront aberrations showed some significant changes in accommodation. In addition to the characteristic sphere reaction accompanying miosis and changes in horizontal prism (Z(1) (1)) in the sense of a convergence movement of the eyeball also occurred. Furthermore defocus rose (Z(2) (0)) and astigmatism (Z(2) (-2)) changed. In higher-order aberrations a decrease in coma-like Zernike polynomials (Z(3) (-1), Z(3) (1)) was found. The most obvious change appeared in spherical aberration (Z(4) (0)) which increased and changed from positive to negative. In addition the secondary astigmatism (Z(4) (-2)) and quadrafoil (Z(4) (4)) rise also increased. The total root mean square (RMS), as well as the higher-order aberrations (RMS-HO) significantly increased in accommodation which is associated with a theoretical reduction of visual acuity. An analysis of the influence of pupil size on aberrations showed significant increases in defocus, spherical aberration, quadrafoil, RMS and RMS HO by increasing pupil diameter. By accommodation-associated miosis, the growing aberrations are partially compensated by focusing on near objects. Temporal analysis of the accommodation process with dynamic wavefront analysis revealed significant delays in pupil response and changing of prism in relation to the sphere reaction. In accommodation to near objects a discrete time ahead of third order aberrations in relation to the sphere response was found. Using dynamic wavefront measurement

  17. Neuroendoscopic Trans-Third Ventricular Approach for Surgical Management of Ecchordosis Physaliphora.

    PubMed

    Adib, Sasan Darius; Bisdas, Sotirios; Bornemann, Antje; Schuhmann, Martin U

    2016-06-01

    We sought to report the successful surgical management of a case of ecchordosis physaliphora (EP) using a neuro-endoscopic trans-third ventricular approach (ETTVA) and to provide a current review of literature on EP. A 57-year-old man presenting with a 2-year history of diplopia due to right abducens nerve palsy and paresthesia of the left body underwent magnetic resonance imaging, which revealed a retroclival intracisternal lesion. The cystic lesion was considered to be most likely EP according to neuroradiologic features. The patient underwent an endoscopic trans-third ventricular resection. A pediatric endoscope was passed from a precoronal burr hole through the left lateral into the third ventricle. The floor of the third ventricle was opened by a 2-micron laser. This approach permitted us to expose the lesion in the retroclival cistern and follow up with a subtotal removal. Remnants of the capsule, which were firmly adherent to small pontine arteries and the left abducens nerve, were left. Histology confirmed EP. The patient recovered well from surgery, and symptoms regressed at clinical follow-up. The endoscopic approach for third ventriculostomy can also be used for the surgical management of retroclival lesions. However, a small pediatric endoscope with an angled view, which can be passed through the floor of the third ventricle without causing harm, is mandatory to explore all important structures in the narrow surgical space. Limitations in this delicate environment are firm adhesions to vessels and nerves because only 1-instrument manipulation is possible and bleeding must be avoided. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Wavefront aberrations of x-ray dynamical diffraction beams.

    PubMed

    Liao, Keliang; Hong, Youli; Sheng, Weifan

    2014-10-01

    The effects of dynamical diffraction in x-ray diffractive optics with large numerical aperture render the wavefront aberrations difficult to describe using the aberration polynomials, yet knowledge of them plays an important role in a vast variety of scientific problems ranging from optical testing to adaptive optics. Although the diffraction theory of optical aberrations was established decades ago, its application in the area of x-ray dynamical diffraction theory (DDT) is still lacking. Here, we conduct a theoretical study on the aberration properties of x-ray dynamical diffraction beams. By treating the modulus of the complex envelope as the amplitude weight function in the orthogonalization procedure, we generalize the nonrecursive matrix method for the determination of orthonormal aberration polynomials, wherein Zernike DDT and Legendre DDT polynomials are proposed. As an example, we investigate the aberration evolution inside a tilted multilayer Laue lens. The corresponding Legendre DDT polynomials are obtained numerically, which represent balanced aberrations yielding minimum variance of the classical aberrations of an anamorphic optical system. The balancing of classical aberrations and their standard deviations are discussed. We also present the Strehl ratio of the primary and secondary balanced aberrations.

  19. On the Definition of Aberration

    NASA Astrophysics Data System (ADS)

    Xu, Minghui; Wang, Guangli

    2014-12-01

    There was a groundbreaking step in the history of astronomy in 1728 when the effect of aberration was discovered by James Bradley (1693-1762). Recently, the solar acceleration, due to the variations in the aberrational effect of extragalactic sources caused by it, has been determined from VLBI observations with an uncertainty of about 0.5 mm{\\cdot}{s^{-1}}{\\cdot}{yr^{-1}} level. As a basic concept in astrometry with a nearly 300-year history, the definition of aberration, however, is still equivocal and discordant in the literature. It has been under continuing debate whether it depends on the relative motion between the observer and the observed source or only on the motion of the observer with respect to the frame of reference. In this paper, we will review the debate and the inconsistency in the definition of the aberration since the last century, and then discuss its definition in detail, which involves the discussions on the planetary aberration, the stellar aberration, the proper motion of an object during the travel time of light from the object to the observer, and the way of selecting the reference frame to express and distinguish the motions of the source and the observer. The aberration is essentially caused by the transformation between coordinate systems, and consequently quantified by the velocity of the observer with respect to the selected reference frame, independent of the motion of the source. Obviously, this nature is totally different from that of the definition given by the IAU WG NFA (Capitaine, 2007) in 2006, which is stated as, ``the apparent angular displacement of the observed position of a celestial object from its geometric position, caused by the finite velocity of light in combination with the motions of the observer and of the observed object.''

  20. Acellular Nerve Allografts in Peripheral Nerve Regeneration: A Comparative Study

    PubMed Central

    Moore, Amy M.; MacEwan, Matthew; Santosa, Katherine B.; Chenard, Kristofer E.; Ray, Wilson Z.; Hunter, Daniel A.; Mackinnon, Susan E.; Johnson, Philip J.

    2011-01-01

    Background Processed nerve allografts offer a promising alternative to nerve autografts in the surgical management of peripheral nerve injuries where short deficits exist. Methods Three established models of acellular nerve allograft (cold-preserved, detergent-processed, and AxoGen® -processed nerve allografts) were compared to nerve isografts and silicone nerve guidance conduits in a 14 mm rat sciatic nerve defect. Results All acellular nerve grafts were superior to silicone nerve conduits in support of nerve regeneration. Detergent-processed allografts were similar to isografts at 6 weeks post-operatively, while AxoGen®-processed and cold-preserved allografts supported significantly fewer regenerating nerve fibers. Measurement of muscle force confirmed that detergent-processed allografts promoted isograft-equivalent levels of motor recovery 16 weeks post-operatively. All acellular allografts promoted greater amounts of motor recovery compared to silicone conduits. Conclusions These findings provide evidence that differential processing for removal of cellular constituents in preparing acellular nerve allografts affects recovery in vivo. PMID:21660979

  1. Nerve Transfer Versus Nerve Graft for Reconstruction of High Ulnar Nerve Injuries.

    PubMed

    Sallam, Asser A; El-Deeb, Mohamed S; Imam, Mohamed A

    2017-04-01

    To assess the efficacy of nerve transfer versus nerve grafting in restoring motor and sensory hand function in patients with complete, isolated high ulnar nerve injuries. A retrospective chart review was performed, at a minimum 2 years of follow-up, of 52 patients suffering complete, isolated high ulnar nerve injury between January 2006 and June 2013 in one specialized hand surgery unit. Twenty-four patients underwent motor and sensory nerve transfers (NT group). Twenty-eight patients underwent sural nerve grafting (NG group). Motor recovery, return of sensibility and complications were examined as outcome measures. The Medical Research Council scale was applied to evaluate sensory and motor recovery. Grip and pinch strengths of the hand were measured. Twenty of 24 patients (83.33%) in the NT group regained M3 grade or greater for the adductor pollicis, the abductor digiti minimi, and the medial 2 lumbricals and interossei, compared with only 16 of 28 patients (57.14%) in the NG group. Means for percentage recovery of grip strengths compared with the other healthy hand were significantly higher for the NT group than the NG group. Sensory recovery of S3 or greater was achieved in more than half of each group with no significant difference between groups. Nerve transfer is favored over nerve grafting in managing high ulnar nerve injuries because of better improvement of motor power and better restoration of grip functions of the hand. Therapeutic IV. Copyright © 2017 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  2. Effect of monochromatic aberrations on photorefractive patterns

    NASA Astrophysics Data System (ADS)

    Campbell, Melanie C. W.; Bobier, W. R.; Roorda, A.

    1995-08-01

    Photorefractive methods have become popular in the measurement of refractive and accommodative states of infants and children owing to their photographic nature and rapid speed of measurement. As in the case of any method that measures the refractive state of the human eye, monochromatic aberrations will reduce the accuracy of the measurement. Monochromatic aberrations cannot be as easily predicted or controlled as chromatic aberrations during the measurement, and accordingly they will introduce measurement errors. This study defines this error or uncertainty by extending the existing paraxial optical analyses of coaxial and eccentric photorefraction. This new optical analysis predicts that, for the amounts of spherical aberration (SA) reported for the human eye, there will be a significant degree of measurement uncertainty introduced for all photorefractive methods. The dioptric amount of this uncertainty may exceed the maximum amount of SA present in the eye. The calculated effects on photorefractive measurement of a real eye with a mixture of spherical aberration and coma are shown to be significant. The ability, developed here, to predict photorefractive patterns corresponding to different amounts and types of monochromatic aberration may in the future lead to an extension of photorefractive methods to the dual measurement of refractive states and aberrations of individual eyes. aberration, retinal image quality,

  3. Chondroitinase C Selectively Degrades Chondroitin Sulfate Glycosaminoglycans that Inhibit Axonal Growth within the Endoneurium of Peripheral Nerve.

    PubMed

    Graham, James B; Muir, David

    2016-01-01

    The success of peripheral nerve regeneration is highly dependent on the regrowth of axons within the endoneurial basal lamina tubes that promote target-oriented pathfinding and appropriate reinnervation. Restoration of nerve continuity at this structural level after nerve transection injury by direct repair and nerve grafting remains a major surgical challenge. Recently, biological approaches that alter the balance of growth inhibitors and promoters in nerve have shown promise to improve appropriate axonal regeneration and recovery of peripheral nerve function. Chondroitin sulfate proteoglycans (CSPGs) are known inhibitors of axonal growth. This growth inhibition is mainly associated with a CSPG's glycosaminoglycan chains. Enzymatic degradation of these chains with chondroitinase eliminates this inhibitory activity and, when applied in vivo, can improve the outcome of nerve repair. To date, these encouraging findings were obtained with chondroitinase ABC (a pan-specific chondroitinase). The aim of this study was to examine the distribution of CSPG subtypes in rodent, rabbit, and human peripheral nerve and to test more selective biological enzymatic approaches to improve appropriate axonal growth within the endoneurium and minimize aberrant growth. Here we provide evidence that the endoneurium, but not the surrounding epineurium, is rich in CSPGs that have glycosaminoglycan chains readily degraded by chondroitinase C. Biochemical studies indicate that chondroitinase C has degradation specificity for 6-sulfated glycosaminoglycans found in peripheral nerve. We found that chondroitinase C degrades and inactivates inhibitory CSPGs within the endoneurium but not so much in the surrounding nerve compartments. Cryoculture bioassays (neurons grown on tissue sections) show that chondroitinase C selectively and significantly enhanced neuritic growth associated with the endoneurial basal laminae without changing growth-inhibiting properties of the surrounding epineurium

  4. Nerve Cross-Bridging to Enhance Nerve Regeneration in a Rat Model of Delayed Nerve Repair

    PubMed Central

    2015-01-01

    There are currently no available options to promote nerve regeneration through chronically denervated distal nerve stumps. Here we used a rat model of delayed nerve repair asking of prior insertion of side-to-side cross-bridges between a donor tibial (TIB) nerve and a recipient denervated common peroneal (CP) nerve stump ameliorates poor nerve regeneration. First, numbers of retrogradely-labelled TIB neurons that grew axons into the nerve stump within three months, increased with the size of the perineurial windows opened in the TIB and CP nerves. Equal numbers of donor TIB axons regenerated into CP stumps either side of the cross-bridges, not being affected by target neurotrophic effects, or by removing the perineurium to insert 5-9 cross-bridges. Second, CP nerve stumps were coapted three months after inserting 0-9 cross-bridges and the number of 1) CP neurons that regenerated their axons within three months or 2) CP motor nerves that reinnervated the extensor digitorum longus (EDL) muscle within five months was determined by counting and motor unit number estimation (MUNE), respectively. We found that three but not more cross-bridges promoted the regeneration of axons and reinnervation of EDL muscle by all the CP motoneurons as compared to only 33% regenerating their axons when no cross-bridges were inserted. The same 3-fold increase in sensory nerve regeneration was found. In conclusion, side-to-side cross-bridges ameliorate poor regeneration after delayed nerve repair possibly by sustaining the growth-permissive state of denervated nerve stumps. Such autografts may be used in human repair surgery to improve outcomes after unavoidable delays. PMID:26016986

  5. Imaging characteristics of Zernike and annular polynomial aberrations.

    PubMed

    Mahajan, Virendra N; Díaz, José Antonio

    2013-04-01

    The general equations for the point-spread function (PSF) and optical transfer function (OTF) are given for any pupil shape, and they are applied to optical imaging systems with circular and annular pupils. The symmetry properties of the PSF, the real and imaginary parts of the OTF, and the modulation transfer function (MTF) of a system with a circular pupil aberrated by a Zernike circle polynomial aberration are derived. The interferograms and PSFs are illustrated for some typical polynomial aberrations with a sigma value of one wave, and 3D PSFs and MTFs are shown for 0.1 wave. The Strehl ratio is also calculated for polynomial aberrations with a sigma value of 0.1 wave, and shown to be well estimated from the sigma value. The numerical results are compared with the corresponding results in the literature. Because of the same angular dependence of the corresponding annular and circle polynomial aberrations, the symmetry properties of systems with annular pupils aberrated by an annular polynomial aberration are the same as those for a circular pupil aberrated by a corresponding circle polynomial aberration. They are also illustrated with numerical examples.

  6. Nodal aberration theory applied to freeform surfaces

    NASA Astrophysics Data System (ADS)

    Fuerschbach, Kyle; Rolland, Jannick P.; Thompson, Kevin P.

    2014-12-01

    When new three-dimensional packages are developed for imaging optical systems, the rotational symmetry of the optical system is often broken, changing its imaging behavior and making the optical performance worse. A method to restore the performance is to use freeform optical surfaces that compensate directly the aberrations introduced from tilting and decentering the optical surfaces. In order to effectively optimize the shape of a freeform surface to restore optical functionality, it is helpful to understand the aberration effect the surface may induce. Using nodal aberration theory the aberration fields induced by a freeform surface in an optical system are explored. These theoretical predications are experimentally validated with the design and implementation of an aberration generating telescope.

  7. Corneal spherical aberration in Saudi population

    PubMed Central

    Al-Sayyari, Tarfah M.; Fawzy, Samah M.; Al-Saleh, Ahmed A.

    2014-01-01

    Purpose To find out the mean corneal spherical aberration and its changes with age in Saudi population. Setting AlHokama Eye Specialist Center, Riyadh, Saudi Arabia. Methods Three hundred (300) eyes of 185 Saudi subjects (97 men and 88 women), whose age ranged from 15 to 85 years old, with matched refractive errors, were divided into three groups according to their age, 100 for each. All the subjects were included in measuring the spherical aberration (SA) using pentacam HR (OCULUS, Germany) at the 6-mm optical zone. Results The mean corneal spherical aberration (CSA) of the fourth order (Z40) of the whole groups was 0.252 ± 0.1154 μm. Patients from 15 to 35 years old have root mean square (RMS) of CSA of 0.2068 ± 0.07151 μm, 0.2370 ± 0.08023 μm was the RMS of CSA of the patients from 35 to 50 years old, while those from 50 to 85 years old have a CSA-RMS of 0.31511 ± 0.1503 μm (P < 0.0001). A positive correlation was found between the spherical aberration (Z40) and the progress of age (r = 0.3429, P < 0.0001). The high order aberration (HOA) presented 28.1% of the total corneal aberrations. While the fourth order corneal spherical aberration constituted 57% of the HOA and 16% of the total aberration. The pupil diameter shows a negative correlation with the increase in age (P = 0.0012). Conclusion Our results showed a CSA (Z40) that is varied among the population, comparable to other studies, and significantly correlates to the progress of age. PMID:25278799

  8. Preoperative transcutaneous electrical nerve stimulation for localizing superficial nerve paths.

    PubMed

    Natori, Yuhei; Yoshizawa, Hidekazu; Mizuno, Hiroshi; Hayashi, Ayato

    2015-12-01

    During surgery, peripheral nerves are often seen to follow unpredictable paths because of previous surgeries and/or compression caused by a tumor. Iatrogenic nerve injury is a serious complication that must be avoided, and preoperative evaluation of nerve paths is important for preventing it. In this study, transcutaneous electrical nerve stimulation (TENS) was used for an in-depth analysis of peripheral nerve paths. This study included 27 patients who underwent the TENS procedure to evaluate the peripheral nerve path (17 males and 10 females; mean age: 59.9 years, range: 18-83 years) of each patient preoperatively. An electrode pen coupled to an electrical nerve stimulator was used for superficial nerve mapping. The TENS procedure was performed on patients' major peripheral nerves that passed close to the surgical field of tumor resection or trauma surgery, and intraoperative damage to those nerves was apprehensive. The paths of the target nerve were detected in most patients preoperatively. The nerve paths of 26 patients were precisely under the markings drawn preoperatively. The nerve path of one patient substantially differed from the preoperative markings with numbness at the surgical region. During surgery, the nerve paths could be accurately mapped preoperatively using the TENS procedure as confirmed by direct visualization of the nerve. This stimulation device is easy to use and offers highly accurate mapping of nerves for surgical planning without major complications. The authors conclude that TENS is a useful tool for noninvasive nerve localization and makes tumor resection a safe and smooth procedure. Copyright © 2015 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  9. Chitin biological absorbable catheters bridging sural nerve grafts transplanted into sciatic nerve defects promote nerve regeneration.

    PubMed

    Wang, Zhi-Yong; Wang, Jian-Wei; Qin, Li-Hua; Zhang, Wei-Guang; Zhang, Pei-Xun; Jiang, Bao-Guo

    2018-06-01

    To investigate the efficacy of chitin biological absorbable catheters in a rat model of autologous nerve transplantation. A segment of sciatic nerve was removed to produce a sciatic nerve defect, and the sural nerve was cut from the ipsilateral leg and used as a graft to bridge the defect, with or without use of a chitin biological absorbable catheter surrounding the graft. The number and morphology of regenerating myelinated fibers, nerve conduction velocity, nerve function index, triceps surae muscle morphology, and sensory function were evaluated at 9 and 12 months after surgery. All of the above parameters were improved in rats in which the nerve graft was bridged with chitin biological absorbable catheters compared with rats without catheters. The results of this study indicate that use of chitin biological absorbable catheters to surround sural nerve grafts bridging sciatic nerve defects promotes recovery of structural, motor, and sensory function and improves muscle fiber morphology. © 2018 John Wiley & Sons Ltd.

  10. Transcranial phase aberration correction using beam simulations and MR-ARFI

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vyas, Urvi, E-mail: urvi.vyas@gmail.com; Kaye, Elena; Pauly, Kim Butts

    2014-03-15

    Purpose: Transcranial magnetic resonance-guided focused ultrasound surgery is a noninvasive technique for causing selective tissue necrosis. Variations in density, thickness, and shape of the skull cause aberrations in the location and shape of the focal zone. In this paper, the authors propose a hybrid simulation-MR-ARFI technique to achieve aberration correction for transcranial MR-guided focused ultrasound surgery. The technique uses ultrasound beam propagation simulations with MR Acoustic Radiation Force Imaging (MR-ARFI) to correct skull-caused phase aberrations. Methods: Skull-based numerical aberrations were obtained from a MR-guided focused ultrasound patient treatment and were added to all elements of the InSightec conformal bone focusedmore » ultrasound surgery transducer during transmission. In the first experiment, the 1024 aberrations derived from a human skull were condensed into 16 aberrations by averaging over the transducer area of 64 elements. In the second experiment, all 1024 aberrations were applied to the transducer. The aberrated MR-ARFI images were used in the hybrid simulation-MR-ARFI technique to find 16 estimated aberrations. These estimated aberrations were subtracted from the original aberrations to result in the corrected images. Each aberration experiment (16-aberration and 1024-aberration) was repeated three times. Results: The corrected MR-ARFI image was compared to the aberrated image and the ideal image (image with zero aberrations) for each experiment. The hybrid simulation-MR-ARFI technique resulted in an average increase in focal MR-ARFI phase of 44% for the 16-aberration case and 52% for the 1024-aberration case, and recovered 83% and 39% of the ideal MR-ARFI phase for the 16-aberrations and 1024-aberration case, respectively. Conclusions: Using one MR-ARFI image and noa priori information about the applied phase aberrations, the hybrid simulation-MR-ARFI technique improved the maximum MR-ARFI phase of the beam's focus.« less

  11. External laryngeal nerve in thyroid surgery: is the nerve stimulator necessary?

    PubMed

    Aina, E N; Hisham, A N

    2001-09-01

    To find out the incidence and type of external laryngeal nerves during operations on the thyroid, and to assess the role of a nerve stimulator in detecting them. Prospective, non-randomised study. Teaching hospital, Malaysia. 317 patients who had 447 dissections between early January 1998 and late November 1999. Number and type of nerves crossing the cricothyroid space, and the usefulness of the nerve stimulator in finding them. The nerve stimulator was used in 206/447 dissections (46%). 392 external laryngeal nerves were seen (88%), of which 196/206 (95%) were detected with the stimulator. However, without the stimulator 196 nerves were detected out of 241 dissections (81%). The stimulator detected 47 (23%) Type I nerves (nerve > 1 cm from the upper edge of superior pole); 86 (42%) Type IIa nerves (nerve < 1 cm from the upper edge of superior pole); and 63 (31%) Type IIb nerves (nerve below upper edge of superior pole). 10 nerves were not detected. When the stimulator was not used the corresponding figures were 32 (13%), 113 (47%), and 51 (21%), and 45 nerves were not seen. If the nerve cannot be found we recommend dissection of capsule close to the medial border of the upper pole of the thyroid to avoid injury to the nerve. Although the use of the nerve stimulator seems desirable, it confers no added advantage in finding the nerve. In the event of uncertainty about whether a structure is the nerve, the stimulator may help to confirm it. However, exposure of the cricothyroid space is most important for good exposure in searching for the external laryngeal nerve.

  12. Anti-forensics of chromatic aberration

    NASA Astrophysics Data System (ADS)

    Mayer, Owen; Stamm, Matthew C.

    2015-03-01

    Over the past decade, a number of information forensic techniques have been developed to identify digital image manipulation and falsification. Recent research has shown, however, that an intelligent forger can use anti-forensic countermeasures to disguise their forgeries. In this paper, an anti-forensic technique is proposed to falsify the lateral chromatic aberration present in a digital image. Lateral chromatic aberration corresponds to the relative contraction or expansion between an image's color channels that occurs due to a lens's inability to focus all wavelengths of light on the same point. Previous work has used localized inconsistencies in an image's chromatic aberration to expose cut-and-paste image forgeries. The anti-forensic technique presented in this paper operates by estimating the expected lateral chromatic aberration at an image location, then removing deviations from this estimate caused by tampering or falsification. Experimental results are presented that demonstrate that our anti-forensic technique can be used to effectively disguise evidence of an image forgery.

  13. Anxiolytic efficacy of repeated oral capsaicin in rats with partial aberration of oral sensory relay to brain.

    PubMed

    Choi, Young-Jun; Kim, Jin Young; Jin, Wei-Peng; Kim, Yoon-Tae; Lee, Jong-Ho; Jahng, Jeong Won

    2015-07-01

    This study was conducted to examine if taste over load with oral capsaicin improves the adverse behavioural effects induced by partial aberration of oral sensory relays to brain with bilateral transections of the lingual and chorda tympani nerves. Male Sprague-Dawley rats received daily 1 ml of 0.02% capsaicin or water drop by drop into the oral cavity following the bilateral transections of the lingual and chorda tympani nerves. Rats were subjected to ambulatory activity, elevated plus maze and forced swim tests after 11th, 14th and 17th daily administration of capsaicin or water, respectively. The basal and stress-induced plasma corticosterone levels were examined after the end of behavioural tests. Ambulatory counts, distance travelled, centre zone activities and rearing were increased, and rostral grooming decreased, during the activity test in capsaicin treated rats. Behavioural scores of capsaicin rats during elevated plus maze test did not differ from control rats. Immobility during the swim test was decreased in capsaicin rats with near significance (P = 0.0547). Repeated oral capsaicin increased both the basal level and stress-induced elevation of plasma corticosterone in rats with bilateral transections of the lingual and chorda tympani nerves. It is concluded that repeated oral administration of capsaicin reduces anxiety-like behaviours in rats that received bilateral transections of the lingual and chorda tympani nerves, and that the increased corticosterone response, possibly modulating the hippocampal neural plasticity, may be implicated in the anxiolytic efficacy of oral capsaicin. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. A Evaluation of Optical Aberrations in Underwater Hologrammetry

    NASA Astrophysics Data System (ADS)

    Kilpatrick, J. M.

    Available from UMI in association with The British Library. An iterative ray-trace procedure is developed in conjunction with semi-analytic expressions for spherical aberration, coma, and astigmatism in the reconstructed holographic images of underwater objects. An exact expression for the astigmatic difference is obtained, based on the geometry of the caustic for refraction. The geometrical characteristics of the aberrated images associated with axial and non-axial field positions are represented by ray intersection diagrams. A third order expression for the wavefront aberration introduced at a planar air/water boundary is given. The associated third order aberration coefficients are used to obtain analytic expressions for the aberrations observed in underwater hologrammetry. The results of the third order treatment are shown to give good agreement with the results obtained by geometrical ray tracing and by direct measurement on the reconstructed real image. The third order aberration coefficients are employed to estimate the limit of resolution in the presence of the aberrations associated with reconstruction in air. In concurrence with practical observations it is found that the estimated resolution is primarily limited by astigmatism. The limitations of the planar window in underwater imaging applications are outlined and various schemes are considered to effect a reduction in the extent of aberration. The analogous problems encountered in underwater photography are examined in order to establish the grounds for a common solution based on a conventional optical corrector. The performance of one such system, the Ivanoff Corrector, is investigated. The spherical aberration associated with axial image formation is evaluated. The equivalence of the third order wavefront aberration introduced at a planar air/water boundary to that introduced upon reconstruction by an appropriate wavelength change is shown to provide a basis for the compensation of aberrations in

  15. Neural progenitor cell implants modulate vascular endothelial growth factor and brain-derived neurotrophic factor expression in rat axotomized neurons.

    PubMed

    Talaverón, Rocío; Matarredona, Esperanza R; de la Cruz, Rosa R; Pastor, Angel M

    2013-01-01

    Axotomy of central neurons leads to functional and structural alterations which largely revert when neural progenitor cells (NPCs) are implanted in the lesion site. The new microenvironment created by NPCs in the host tissue might modulate in the damaged neurons the expression of a high variety of molecules with relevant roles in the repair mechanisms, including neurotrophic factors. In the present work, we aimed to analyze changes in neurotrophic factor expression in axotomized neurons induced by NPC implants. For this purpose, we performed immunofluorescence followed by confocal microscopy analysis for the detection of vascular endothelial growth factor (VEGF), brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3) and nerve growth factor (NGF) on brainstem sections from rats with axotomy of abducens internuclear neurons that received NPC implants (implanted group) or vehicle injections (axotomized group) in the lesion site. Control abducens internuclear neurons were strongly immunoreactive to VEGF and BDNF but showed a weak staining for NT-3 and NGF. Comparisons between groups revealed that lesioned neurons from animals that received NPC implants showed a significant increase in VEGF content with respect to animals receiving vehicle injections. However, the immunoreactivity for BDNF, which was increased in the axotomized group as compared to control, was not modified in the implanted group. The modifications induced by NPC implants on VEGF and BDNF content were specific for the population of axotomized abducens internuclear neurons since the neighboring abducens motoneurons were not affected. Similar levels of NT-3 and NGF immunolabeling were obtained in injured neurons from axotomized and implanted animals. Among all the analyzed neurotrophic factors, only VEGF was expressed by the implanted cells in the lesion site. Our results point to a role of NPC implants in the modulation of neurotrophic factor expression by lesioned central neurons, which might

  16. Structural parameters of collagen nerve grafts influence peripheral nerve regeneration.

    PubMed

    Stang, Felix; Fansa, Hisham; Wolf, Gerald; Reppin, Michael; Keilhoff, Gerburg

    2005-06-01

    Large nerve defects require nerve grafts to allow regeneration. To avoid donor nerve problems the concept of tissue engineering was introduced into nerve surgery. However, non-neuronal grafts support axonal regeneration only to a certain extent. They lack viable Schwann cells which provide neurotrophic and neurotopic factors and guide the sprouting nerve. This experimental study used the rat sciatic nerve to bridge 2 cm nerve gaps with collagen (type I/III) tubes. The tubes were different in their physical structure (hollow versus inner collagen skeleton, different inner diameters). To improve regeneration Schwann cells were implanted. After 8 weeks the regeneration process was monitored clinically, histologically and morphometrically. Autologous nerve grafts and collagen tubes without Schwann cells served as control. In all parameters autologous nerve grafts showed best regeneration. Nerve regeneration in a noteworthy quality was also seen with hollow collagen tubes and tubes with reduced lumen, both filled with Schwann cells. The inner skeleton, however, impaired nerve regeneration independent of whether Schwann cells were added or not. This indicates that not only viable Schwann cells are an imperative prerequisite but also structural parameters determine peripheral nerve regeneration.

  17. HCV RNA Genomic sequences and HCV-E2 glycoprotein in sural nerve biopsies from HCV-infected patients with peripheral neuropathy.

    PubMed

    Russi, S; Sansonno, D; Monaco, S; Mariotto, S; Ferrari, S; Pavone, F; Lauletta, G; Dammacco, F

    2018-06-01

    Peripheral neuropathy (PN), the major neurological complication of chronic HCV infection, is frequently associated with mixed cryoglobulinaemia (MC) and small-vessel systemic vasculitis. While humoral and cell-mediated immune mechanisms are suspected to act together in an aberrant immune response that results in peripheral nerve damage, the role of HCV remains largely speculative. The possible demonstration of HCV in peripheral nerve tissue would obviously assume important pathogenic implications. We studied sural nerve biopsies from 11 HCV-positive patients with neuropathic symptoms: five with and six without MC. In situ hybridization (ISH) and immunofluorescence studies were carried out to detect genomic and antigenomic HCV RNA sequences and HCV-encoded E2-glycoprotein, respectively. Epineurial vascular deposits of E2-glycoprotein were found in four (80%) MC and in two (33.3%) non-MC patients, respectively. These findings were enhanced by the perivascular deposition of positive-, though not negative-strand replicative RNA, as also found in the nerve extracts of all patients. Mild inflammatory cell infiltrates with no deposits of immunoglobulins and/or complement proteins were revealed around small vessels, without distinct vasculitis changes between MC and non-MC patients. These results indicate that nerve vascular HCV RNA/E2 deposits associated to perivascular inflammatory infiltrates were similar in chronically HCV-infected patients, regardless of cryoglobulin occurrence. Given the failure to demonstrate HCV productive infection in the examined sural nerve biopsies, nerve damage is likely to result from virus-triggered immune-mediated mechanisms. © 2017 British Neuropathological Society.

  18. High Ulnar Nerve Injuries: Nerve Transfers to Restore Function.

    PubMed

    Patterson, Jennifer Megan M

    2016-05-01

    Peripheral nerve injuries are challenging problems. Nerve transfers are one of many options available to surgeons caring for these patients, although they do not replace tendon transfers, nerve graft, or primary repair in all patients. Distal nerve transfers for the treatment of high ulnar nerve injuries allow for a shorter reinnervation period and improved ulnar intrinsic recovery, which are critical to function of the hand. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Chitosan conduits combined with nerve growth factor microspheres repair facial nerve defects

    PubMed Central

    Liu, Huawei; Wen, Weisheng; Hu, Min; Bi, Wenting; Chen, Lijie; Liu, Sanxia; Chen, Peng; Tan, Xinying

    2013-01-01

    Microspheres containing nerve growth factor for sustained release were prepared by a compound method, and implanted into chitosan conduits to repair 10-mm defects on the right buccal branches of the facial nerve in rabbits. In addition, chitosan conduits combined with nerve growth factor or normal saline, as well as autologous nerve, were used as controls. At 90 days post-surgery, the muscular atrophy on the right upper lip was more evident in the nerve growth factor and normal sa-line groups than in the nerve growth factor-microspheres and autologous nerve groups. physiological analysis revealed that the nerve conduction velocity and amplitude were significantly higher in the nerve growth factor-microspheres and autologous nerve groups than in the nerve growth factor and normal saline groups. Moreover, histological observation illustrated that the di-ameter, number, alignment and myelin sheath thickness of myelinated nerves derived from rabbits were higher in the nerve growth factor-microspheres and autologous nerve groups than in the nerve growth factor and normal saline groups. These findings indicate that chitosan nerve conduits bined with microspheres for sustained release of nerve growth factor can significantly improve facial nerve defect repair in rabbits. PMID:25206635

  20. Aberrated laser beams in terms of Zernike polynomials

    NASA Astrophysics Data System (ADS)

    Alda, Javier; Alonso, Jose; Bernabeu, Eusebio

    1996-11-01

    The characterization of light beams has devoted a lot of attention in the past decade. Several formalisms have been presented to treat the problem of parameter invariance and characterization in the propagation of light beam along ideal, ABCD, optical systems. The hard and soft apertured optical systems have been treated too. Also some aberrations have been analyzed, but it has not appeared a formalism able to treat the problem as a whole. In this contribution we use a classical approach to describe the problem of aberrated, and therefore apertured, light beams. The wavefront aberration is included in a pure phase term expanded in terms of the Zernike polynomials. Then, we can use the relation between the lower order Zernike polynomia and the Seidel or third order aberrations. We analyze the astigmatism, the spherical aberration and the coma, and we show how higher order aberrations can be taken into account. We have calculated the divergence, and the radius of curvature of such aberrated beams and the influence of these aberrations in the quality of the light beam. Some numerical simulations have been done to illustrate the method.

  1. Structural centrosome aberrations promote non-cell-autonomous invasiveness.

    PubMed

    Ganier, Olivier; Schnerch, Dominik; Oertle, Philipp; Lim, Roderick Yh; Plodinec, Marija; Nigg, Erich A

    2018-05-02

    Centrosomes are the main microtubule-organizing centers of animal cells. Although centrosome aberrations are common in tumors, their consequences remain subject to debate. Here, we studied the impact of structural centrosome aberrations, induced by deregulated expression of ninein-like protein (NLP), on epithelial spheres grown in Matrigel matrices. We demonstrate that NLP-induced structural centrosome aberrations trigger the escape ("budding") of living cells from epithelia. Remarkably, all cells disseminating into the matrix were undergoing mitosis. This invasive behavior reflects a novel mechanism that depends on the acquisition of two distinct properties. First, NLP-induced centrosome aberrations trigger a re-organization of the cytoskeleton, which stabilizes microtubules and weakens E-cadherin junctions during mitosis. Second, atomic force microscopy reveals that cells harboring these centrosome aberrations display increased stiffness. As a consequence, mitotic cells are pushed out of mosaic epithelia, particularly if they lack centrosome aberrations. We conclude that centrosome aberrations can trigger cell dissemination through a novel, non-cell-autonomous mechanism, raising the prospect that centrosome aberrations contribute to the dissemination of metastatic cells harboring normal centrosomes. © 2018 The Authors. Published under the terms of the CC BY NC ND 4.0 license.

  2. [Magnetic resonance imaging features in two Chinese family with congenital fibrosis of extraocular muscles].

    PubMed

    Wu, Li; Zhou, Lian-Hong; Liu, Chang-Sheng; Cha, Yun-Fei; Wang, Jiong; Xing, Yi-Qiao

    2009-11-01

    The aim of this article was to investigate the structural basis of ocular motility and visual abnormalities in humans with congenital fibrosis of the extraocular muscles (CFEOM). 17 volunteers from 2 CFEOM pedigrees Clinical ophthalmic and motility examed and 18 normal control subjects were correlated with thin-sectioned magnetic resonance imaging (MRI) across the orbit and the brain-stem level. Subjects with CFEOM had severe bilateral blepharoptosis, limited supraduction, and variable ophthalmoplegia. In affected subjects, MRI demonstrated atrophy of the levator palpebrae superioris, all EOMs, and the optic nerves, and small or absent orbital motor nerves. The oculomotor nerve was most severely hypoplastic, but the abducens was also affected. Subjects with CFEOM exhibited subclinical but highly significant reduction from normal in mean optic nerve size (P < 0.05). There are also some difference between the two CFEOM pedigrees. These findings suggest that neuronal disease is primary in CFEOM, with myopathy arising secondary to abnormal innervation and the oculomotor nucleus and trochlear nucleus of the abnormalities defects.

  3. Whole eye wavefront aberrations in Mexican male subjects.

    PubMed

    Cantú, Roberto; Rosales, Marco A; Tepichín, Eduardo; Curioca, Andrée; Montes, Victor; Bonilla, Julio

    2004-01-01

    To analyze the characteristics, incidence, and appearance of wavefront aberrations in undilated, normal, unoperated eyes. Eighty-eight eyes of 44 healthy male Mexican subjects (mean age 25.32 years, range 18 to 36 yr) were divided into three groups based on uncorrected visual acuity of greater than or equal to 20/20, 20/30, or 20/40. UCVA measurements were obtained using an Acuity Max computer screen chart. Wavefront aberrations were measured with the Nidek OPD-Scan ARK 10000, Ver. 1.11b. All measurements were carried out at the same center by the same technician during a single session, following manufacturer instructions. Background illumination was 3 Lux. Wavefront aberration measurements for each group were statistically analyzed using StatView; an average eye was characterized and the resulting aberrations were simulated using MATLAB. We obtained wavefront aberration maps for the 20/20 undilated normal unoperated eyes for total, low, and high order aberration coefficients. Wavefront maps for right eyes were practically the same as those for left eyes. Higher aberrations did not contribute substantially to total wavefront analysis. Average aberrations of this "normal eye" will be used as criteria to decide the necessity of wavefront-guided ablation in our facilities. We will focus on the nearly zero average of high order aberrations in this normal whole eye as a reference to be matched.

  4. Accommodation to wavefront vergence and chromatic aberration.

    PubMed

    Wang, Yinan; Kruger, Philip B; Li, James S; Lin, Peter L; Stark, Lawrence R

    2011-05-01

    Longitudinal chromatic aberration (LCA) provides a cue to accommodation with small pupils. However, large pupils increase monochromatic aberrations, which may obscure chromatic blur. In this study, we examined the effect of pupil size and LCA on accommodation. Accommodation was recorded by infrared optometer while observers (nine normal trichromats) viewed a sinusoidally moving Maltese cross target in a Badal stimulus system. There were two illumination conditions: white (3000 K; 20 cd/m) and monochromatic (550 nm with 10 nm bandwidth; 20 cd/m) and two artificial pupil conditions (3 and 5.7 mm). Separately, static measurements of wavefront aberration were made with the eye accommodating to targets between 0 and 4 D (COAS, Wavefront Sciences). Large individual differences in accommodation to wavefront vergence and to LCA are a hallmark of accommodation. LCA continues to provide a signal at large pupil sizes despite higher levels of monochromatic aberrations. Monochromatic aberrations may defend against chromatic blur at high spatial frequencies, but accommodation responds best to optical vergence and to LCA at 3 c/deg where blur from higher order aberrations is less.

  5. The First Experience of Triple Nerve Transfer in Proximal Radial Nerve Palsy.

    PubMed

    Emamhadi, Mohammadreza; Andalib, Sasan

    2018-01-01

    Injury to distal portion of posterior cord of brachial plexus leads to palsy of radial and axillary nerves. Symptoms are usually motor deficits of the deltoid muscle; triceps brachii muscle; and extensor muscles of the wrist, thumb, and fingers. Tendon transfers, nerve grafts, and nerve transfers are options for surgical treatment of proximal radial nerve palsy to restore some motor functions. Tendon transfer is painful, requires a long immobilization, and decreases donor muscle strength; nevertheless, nerve transfer produces promising outcomes. We present a patient with proximal radial nerve palsy following a blunt injury undergoing triple nerve transfer. The patient was involved in a motorcycle accident with complete palsy of the radial and axillary nerves. After 6 months, on admission, he showed spontaneous recovery of axillary nerve palsy, but radial nerve palsy remained. We performed triple nerve transfer, fascicle of ulnar nerve to long head of the triceps branch of radial nerve, flexor digitorum superficialis branch of median nerve to extensor carpi radialis brevis branch of radial nerve, and flexor carpi radialis branch of median nerve to posterior interosseous nerve, for restoration of elbow, wrist, and finger extensions, respectively. Our experience confirmed functional elbow, wrist, and finger extensions in the patient. Triple nerve transfer restores functions of the upper limb in patients with debilitating radial nerve palsy after blunt injuries. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Sixth-order wave aberration theory of ultrawide-angle optical systems.

    PubMed

    Lu, Lijun; Cao, Yiqing

    2017-10-20

    In this paper, we develop sixth-order wave aberration theory of ultrawide-angle optical systems like fisheye lenses. Based on the concept and approach to develop wave aberration theory of plane-symmetric optical systems, we first derive the sixth-order intrinsic wave aberrations and the fifth-order ray aberrations; second, we present a method to calculate the pupil aberration of such kind of optical systems to develop the extrinsic aberrations; third, the relation of aperture-ray coordinates between adjacent optical surfaces is fitted with the second-order polynomial to improve the calculation accuracy of the wave aberrations of a fisheye lens with a large acceptance aperture. Finally, the resultant aberration expressions are applied to calculate the aberrations of two design examples of fisheye lenses; the calculation results are compared with the ray-tracing ones with Zemax software to validate the aberration expressions.

  7. Nerve ultrasound shows subclinical peripheral nerve involvement in neurofibromatosis type 2.

    PubMed

    Telleman, Johan A; Stellingwerff, Menno D; Brekelmans, Geert J; Visser, Leo H

    2018-02-01

    Neurofibromatosis type 2 (NF2) is mainly associated with central nervous system (CNS) tumors. Peripheral nerve involvement is described in symptomatic patients, but evidence of subclinical peripheral nerve involvement is scarce. We conducted a cross-sectional pilot study in 2 asymptomatic and 3 minimally symptomatic patients with NF2 to detect subclinical peripheral nerve involvement. Patients underwent clinical examination, nerve conduction studies (NCS), and high-resolution ultrasonography (HRUS). A total of 30 schwannomas were found, divided over 20 nerve segments (33.9% of all investigated nerve segments). All patients had at least 1 schwannoma. Schwannomas were identified with HRUS in 37% of clinically unaffected nerve segments and 50% of nerve segments with normal NCS findings. HRUS shows frequent subclinical peripheral nerve involvement in NF2. Clinicians should consider peripheral nerve involvement as a cause of weakness and sensory loss in the extremities in patients with this disease. Muscle Nerve 57: 312-316, 2018. © 2017 Wiley Periodicals, Inc.

  8. Spherical aberrations of human astigmatic corneas.

    PubMed

    Zhao, Huawei; Dai, Guang-Ming; Chen, Li; Weeber, Henk A; Piers, Patricia A

    2011-11-01

    To evaluate whether the average spherical aberration of human astigmatic corneas is statistically equivalent to human nonastigmatic corneas. Spherical aberrations of 445 astigmatic corneas prior to laser vision correction were retrospectively investigated to determine Zernike coefficients for central corneal areas 6 mm in diameter using CTView (Sarver and Associates). Data were divided into groups according to cylinder power (0.01 to 0.25 diopters [D], 0.26 to 0.75 D, 0.76 to 1.06 D, 1.07 to 1.53 D, 1.54 to 2.00 D, and >2.00 D) and according to age by decade. Spherical aberrations were correlated with age and astigmatic power among groups and the entire population. Statistical analyses were conducted, and P<.05 was considered statistically significant. Mean patient age was 42.6±11 years. Astigmatic corneas had an average astigmatic power of 0.78±0.58 D and mean spherical aberration was 0.25±0.13 μm for the entire population and approximately the same (0.27 μm) for individual groups, ranging from 0.23 to 0.29 μm (P>.05 for all tested groups). Mean spherical aberration of astigmatic corneas was not correlated significantly with cylinder power or age (P>.05). Spherical aberrations are similar to those of nonastigmatic corneas, permitting the use of these additional data in the design of aspheric toric intra-ocular lenses. Copyright 2011, SLACK Incorporated.

  9. High order aberration and straylight evaluation after cataract surgery with implantation of an aspheric, aberration correcting monofocal intraocular lens

    PubMed Central

    Kretz, Florian T A; Tandogan, Tamer; Khoramnia, Ramin; Auffarth, Gerd U

    2015-01-01

    AIM To evaluate the quality of vision in respect to high order aberrations and straylight perception after implantation of an aspheric, aberration correcting, monofocal intraocular lens (IOL). METHODS Twenty-one patients (34 eyes) aged 50 to 83y underwent cataract surgery with implantation of an aspheric, aberration correcting IOL (Tecnis ZCB00, Abbott Medical Optics). Three months after surgery they were examined for uncorrected (UDVA) and corrected distance visual acuity (CDVA), contrast sensitivity (CS) under photopic and mesopic conditions with and without glare source, ocular high order aberrations (HOA, Zywave II) and retinal straylight (C-Quant). RESULTS Postoperatively, patients achieved a postoperative CDVA of 0.0 logMAR or better in 97.1% of eyes. Mean values of high order abberations were +0.02±0.27 (primary coma components) and -0.04±0.16 (spherical aberration term). Straylight values of the C-Quant were 1.35±0.44 log which is within normal range of age matched phakic patients. The CS measurements under mesopic and photopic conditions in combination with and without glare did not show any statistical significance in the patient group observed (P≥0.28). CONCLUSION The implantation of an aspherical aberration correcting monofocal IOL after cataract surgery resulted in very low residual higher order aberration (HOA) and normal straylight. PMID:26309872

  10. Electromechanical Nerve Stimulator

    NASA Technical Reports Server (NTRS)

    Tcheng, Ping; Supplee, Frank H., Jr.; Prass, Richard L.

    1993-01-01

    Nerve stimulator applies and/or measures precisely controlled force and/or displacement to nerve so response of nerve measured. Consists of three major components connected in tandem: miniature probe with spherical tip; transducer; and actuator. Probe applies force to nerve, transducer measures force and sends feedback signal to control circuitry, and actuator positions force transducer and probe. Separate box houses control circuits and panel. Operator uses panel to select operating mode and parameters. Stimulator used in research to characterize behavior of nerve under various conditions of temperature, anesthesia, ventilation, and prior damage to nerve. Also used clinically to assess damage to nerve from disease or accident and to monitor response of nerve during surgery.

  11. Tissue-engineered spiral nerve guidance conduit for peripheral nerve regeneration.

    PubMed

    Chang, Wei; Shah, Munish B; Lee, Paul; Yu, Xiaojun

    2018-06-01

    Recently in peripheral nerve regeneration, preclinical studies have shown that the use of nerve guidance conduits (NGCs) with multiple longitudinally channels and intra-luminal topography enhance the functional outcomes when bridging a nerve gap caused by traumatic injury. These features not only provide guidance cues for regenerating nerve, but also become the essential approaches for developing a novel NGC. In this study, a novel spiral NGC with aligned nanofibers and wrapped with an outer nanofibrous tube was first developed and investigated. Using the common rat sciatic 10-mm nerve defect model, the in vivo study showed that a novel spiral NGC (with and without inner nanofibers) increased the successful rate of nerve regeneration after 6 weeks recovery. Substantial improvements in nerve regeneration were achieved by combining the spiral NGC with inner nanofibers and outer nanofibrous tube, based on the results of walking track analysis, electrophysiology, nerve histological assessment, and gastrocnemius muscle measurement. This demonstrated that the novel spiral NGC with inner aligned nanofibers and wrapped with an outer nanofibrous tube provided a better environment for peripheral nerve regeneration than standard tubular NGCs. Results from this study will benefit for future NGC design to optimize tissue-engineering strategies for peripheral nerve regeneration. We developed a novel spiral nerve guidance conduit (NGC) with coated aligned nanofibers. The spiral structure increases surface area by 4.5 fold relative to a tubular NGC. Furthermore, the aligned nanofibers was coated on the spiral walls, providing cues for guiding neurite extension. Finally, the outside of spiral NGC was wrapped with randomly nanofibers to enhance mechanical strength that can stabilize the spiral NGC. Our nerve histological data have shown that the spiral NGC had 50% more myelinated axons than a tubular structure for nerve regeneration across a 10 mm gap in a rat sciatic nerve

  12. Accommodation to Wavefront Vergence and Chromatic Aberration

    PubMed Central

    Wang, Yinan; Kruger, Philip B.; Li, James S.; Lin, Peter L.; Stark, Lawrence R.

    2011-01-01

    Purpose Longitudinal chromatic aberration (LCA) provides a cue to accommodation with small pupils. However, large pupils increase monochromatic aberrations, which may obscure chromatic blur. In the present study, we examined the effect of pupil size and LCA on accommodation. Methods Accommodation was recorded by infrared optometer while observers (nine normal trichromats) viewed a sinusoidally moving Maltese cross target in a Badal stimulus system. There were two illumination conditions: white (3000 K; 20 cd/m2) and monochromatic (550 nm with 10 nm bandwidth; 20 cd/m2) and two artificial pupil conditions (3 mm and 5.7 mm). Separately, static measurements of wavefront aberration were made with the eye accommodating to targets between 0 and 4 D (COAS, Wavefront Sciences). Results Large individual differences in accommodation to wavefront vergence and to LCA are a hallmark of accommodation. LCA continues to provide a signal at large pupil sizes despite higher levels of monochromatic aberrations. Conclusions Monochromatic aberrations may defend against chromatic blur at high spatial frequencies, but accommodation responds best to optical vergence and to LCA at 3 c/deg where blur from higher order aberrations is less. PMID:21317666

  13. A System for Studying Facial Nerve Function in Rats through Simultaneous Bilateral Monitoring of Eyelid and Whisker Movements

    PubMed Central

    Heaton, James T.; Kowaleski, Jeffrey M.; Bermejo, Roberto; Zeigler, H. Philip; Ahlgren, David J.; Hadlock, Tessa A.

    2008-01-01

    The occurrence of inappropriate co-contraction of facially innervated muscles in humans (synkinesis) is a common sequela of facial nerve injury and recovery. We have developed a system for studying facial nerve function and synkinesis in restrained rats using non-contact opto-electronic techniques that enable simultaneous bilateral monitoring of eyelid and whisker movements. Whisking is monitored in high spatio-temporal resolution using laser micrometers, and eyelid movements are detected using infrared diode and phototransistor pairs that respond to the increased reflection when the eyelids cover the cornea. To validate the system, eight rats were tested with multiple five-minute sessions that included corneal air puffs to elicit blink and scented air flows to elicit robust whisking. Four rats then received unilateral facial nerve section and were tested at weeks 3–6. Whisking and eye blink behavior occurred both spontaneously and under stimulus control, with no detectable difference from published whisking data. Proximal facial nerve section caused an immediate ipsilateral loss of whisking and eye blink response, but some ocular closures emerged due to retractor bulbi muscle function. The independence observed between whisker and eyelid control indicates that this system may provide a powerful tool for identifying abnormal co-activation of facial zones resulting from aberrant axonal regeneration. PMID:18442856

  14. Comparison of Aberrations After Standard and Customized Refractive Surgery

    NASA Astrophysics Data System (ADS)

    Fang, L.; He, X.; Wang, Y.

    2013-09-01

    To detect possible differences in residual wavefront aberrations between standard and customized laser refractive surgery based onmathematical modeling, the residual optical aberrations after conventional and customized laser refractive surgery were compared accordingto the ablation profile with transition zone. The results indicated that ablation profile has a significant impact on the residual aberrations.The amount of residual aberrations for conventional correction is higher than that for customized correction. Additionally, the residualaberrations for high myopia eyes are markedly larger than those for moderate myopia eyes. For a 5 mm pupil, the main residual aberrationterm is coma and yet it is spherical aberration for a 7 mm pupil. When the pupil diameter is the same as optical zone or greater, themagnitudes of residual aberrations is obviously larger than that for a smaller pupil. In addition, the magnitudes of the residual fifth orsixth order aberrations are relatively large, especially secondary coma in a 6 mm pupil and secondary spherical aberration in a 7 mm pupil.Therefore, the customized ablation profile may be superior to the conventional correction even though the transition zone and treatmentdecentration are taken into account. However, the customized ablation profile will still induce significant amount of residual aberrations.

  15. Theoretical investigation of aberrations upon ametropic human eyes

    NASA Astrophysics Data System (ADS)

    Tan, Bo; Chen, Ying-Ling; Lewis, J. W. L.; Baker, Kevin

    2003-11-01

    The human eye aberrations are important for visual acuity and ophthalmic diagnostics and surgical procedures. Reported monochromatic aberration data of the normal 20/20 human eyes are scarce. There exist even fewer reports of the relation between ametropic conditions and aberrations. We theoretically investigate the monochromatic and chromatic aberrations of human eyes for refractive errors of -10 to +10 diopters. Schematic human eye models are employed using optical design software for axial, index, and refractive types of ametropia.

  16. Anterior Corneal, Posterior Corneal, and Lenticular Contributions to Ocular Aberrations.

    PubMed

    Atchison, David A; Suheimat, Marwan; Mathur, Ankit; Lister, Lucas J; Rozema, Jos

    2016-10-01

    To determine the corneal surfaces and lens contributions to ocular aberrations. There were 61 healthy participants with ages ranging from 20 to 55 years and refractions -8.25 diopters (D) to +3.25 D. Anterior and posterior corneal topographies were obtained with an Oculus Pentacam, and ocular aberrations were obtained with an iTrace aberrometer. Raytracing through models of corneas provided total corneal and surface component aberrations for 5-mm-diameter pupils. Lenticular contributions were given as differences between ocular and corneal aberrations. Theoretical raytracing investigated influence of object distance on aberrations. Apart from defocus, the highest aberration coefficients were horizontal astigmatism, horizontal coma, and spherical aberration. Most correlations between lenticular and ocular parameters were positive and significant, with compensation of total corneal aberrations by lenticular aberrations for 5/12 coefficients. Anterior corneal aberrations were approximately three times higher than posterior corneal aberrations and usually had opposite signs. Corneal topographic centers were displaced from aberrometer pupil centers by 0.32 ± 0.19 mm nasally and 0.02 ± 0.16 mm inferiorly; disregarding corneal decentration relative to pupil center was significant for oblique astigmatism, horizontal coma, and horizontal trefoil. An object at infinity, rather than at the image in the anterior cornea, gave incorrect aberration estimates of the posterior cornea. Corneal and lenticular aberration magnitudes are similar, and aberrations of the anterior corneal surface are approximately three times those of the posterior surface. Corneal decentration relative to pupil center has significant effects on oblique astigmatism, horizontal coma, and horizontal trefoil. When estimating component aberrations, it is important to use correct object/image conjugates and heights at surfaces.

  17. Direct Administration of Nerve-Specific Contrast to Improve Nerve Sparing Radical Prostatectomy

    PubMed Central

    Barth, Connor W.; Gibbs, Summer L.

    2017-01-01

    Nerve damage remains a major morbidity following nerve sparing radical prostatectomy, significantly affecting quality of life post-surgery. Nerve-specific fluorescence guided surgery offers a potential solution by enhancing nerve visualization intraoperatively. However, the prostate is highly innervated and only the cavernous nerve structures require preservation to maintain continence and potency. Systemic administration of a nerve-specific fluorophore would lower nerve signal to background ratio (SBR) in vital nerve structures, making them difficult to distinguish from all nervous tissue in the pelvic region. A direct administration methodology to enable selective nerve highlighting for enhanced nerve SBR in a specific nerve structure has been developed herein. The direct administration methodology demonstrated equivalent nerve-specific contrast to systemic administration at optimal exposure times. However, the direct administration methodology provided a brighter fluorescent nerve signal, facilitating nerve-specific fluorescence imaging at video rate, which was not possible following systemic administration. Additionally, the direct administration methodology required a significantly lower fluorophore dose than systemic administration, that when scaled to a human dose falls within the microdosing range. Furthermore, a dual fluorophore tissue staining method was developed that alleviates fluorescence background signal from adipose tissue accumulation using a spectrally distinct adipose tissue specific fluorophore. These results validate the use of the direct administration methodology for specific nerve visualization with fluorescence image-guided surgery, which would improve vital nerve structure identification and visualization during nerve sparing radical prostatectomy. PMID:28255352

  18. Direct Administration of Nerve-Specific Contrast to Improve Nerve Sparing Radical Prostatectomy.

    PubMed

    Barth, Connor W; Gibbs, Summer L

    2017-01-01

    Nerve damage remains a major morbidity following nerve sparing radical prostatectomy, significantly affecting quality of life post-surgery. Nerve-specific fluorescence guided surgery offers a potential solution by enhancing nerve visualization intraoperatively. However, the prostate is highly innervated and only the cavernous nerve structures require preservation to maintain continence and potency. Systemic administration of a nerve-specific fluorophore would lower nerve signal to background ratio (SBR) in vital nerve structures, making them difficult to distinguish from all nervous tissue in the pelvic region. A direct administration methodology to enable selective nerve highlighting for enhanced nerve SBR in a specific nerve structure has been developed herein. The direct administration methodology demonstrated equivalent nerve-specific contrast to systemic administration at optimal exposure times. However, the direct administration methodology provided a brighter fluorescent nerve signal, facilitating nerve-specific fluorescence imaging at video rate, which was not possible following systemic administration. Additionally, the direct administration methodology required a significantly lower fluorophore dose than systemic administration, that when scaled to a human dose falls within the microdosing range. Furthermore, a dual fluorophore tissue staining method was developed that alleviates fluorescence background signal from adipose tissue accumulation using a spectrally distinct adipose tissue specific fluorophore. These results validate the use of the direct administration methodology for specific nerve visualization with fluorescence image-guided surgery, which would improve vital nerve structure identification and visualization during nerve sparing radical prostatectomy.

  19. Nerve regeneration in nerve grafts conditioned by vibration exposure.

    PubMed

    Bergman, S; Widerberg, A; Danielsen, N; Lundborg, G; Dahlin, L B

    1995-01-01

    Regeneration distances were studied in nerves from vibration-exposed limbs. One hind limb of anaesthetized rats was attached to a vibration exciter and exposed to vibration (80 Hz/32 m/s2) for 5 h/day for 2 or 5 days. Seven days after the latest vibration period a 10-mm long nerve graft was taken from the vibrated sciatic nerve and sutured into a corresponding defect in the con-tralateral sciatic nerve and vice versa, thereby creating two different models within the same animal: (i) regeneration from a freshly transected unvibrated nerve into a vibrated graft and (ii) regeneration from a vibrated nerve into a fresh nerve graft (vibrated recipient side). Four, 6 or 8 days postoperatively (p.o.) the distances achieved by the regenerating axons were determined using the pinch reflex test. Two days of vibration did not influence the regeneration, but 5 days of vibration reduced the initial delay period and a slight reduction of regeneration rate was observed. After 5 days of vibration an increased regeneration distance was observed in both models at day 4 p.o. and at day 6 p.o. in vibrated grafts. This study demonstrates that vibration can condition peripheral nerves and this may be caused by local changes in the peripheral nerve trunk and in the neuron itself.

  20. The role of great auricular-facial nerve neurorrhaphy in facial nerve damage.

    PubMed

    Sun, Yan; Liu, Limei; Han, Yuechen; Xu, Lei; Zhang, Daogong; Wang, Haibo

    2015-01-01

    Facial nerve is easy to be damaged, and there are many reconstructive methods for facial nerve reconstructive, such as facial nerve end to end anastomosis, the great auricular nerve graft, the sural nerve graft, or hypoglossal-facial nerve anastomosis. However, there is still little study about great auricular-facial nerve neurorrhaphy. The aim of the present study was to identify the role of great auricular-facial nerve neurorrhaphy and the mechanism. Rat models of facial nerve cut (FC), facial nerve end to end anastomosis (FF), facial-great auricular neurorrhaphy (FG), and control (Ctrl) were established. Apex nasi amesiality observation, electrophysiology and immunofluorescence assays were employed to investigate the function and mechanism. In apex nasi amesiality observation, it was found apex nasi amesiality of FG group was partly recovered. Additionally, electrophysiology and immunofluorescence assays revealed that facial-great auricular neurorrhaphy could transfer nerve impulse and express AChR which was better than facial nerve cut and worse than facial nerve end to end anastomosis. The present study indicated that great auricular-facial nerve neurorrhaphy is a substantial solution for facial lesion repair, as it is efficiently preventing facial muscles atrophy by generating neurotransmitter like ACh.

  1. Nodal aberration theory for wild-filed asymmetric optical systems

    NASA Astrophysics Data System (ADS)

    Chen, Yang; Cheng, Xuemin; Hao, Qun

    2016-10-01

    Nodal Aberration Theory (NAT) was used to calculate the zero field position in Full Field Display (FFD) for the given aberration term. Aiming at wide-filed non-rotational symmetric decentered optical systems, we have presented the nodal geography behavior of the family of third-order and fifth-order aberrations. Meanwhile, we have calculated the wavefront aberration expressions when one optical element in the system is tilted, which was not at the entrance pupil. By using a three-piece-cellphone lens example in optical design software CodeV, the nodal geography is testified under several situations; and the wavefront aberrations are calculated when the optical element is tilted. The properties of the nodal aberrations are analyzed by using Fringe Zernike coefficients, which are directly related with the wavefront aberration terms and usually obtained by real ray trace and wavefront surface fitting.

  2. Aberration corrected STEM by means of diffraction gratings

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Linck, Martin; Ercius, Peter A.; Pierce, Jordan S.

    In the past 15 years, the advent of aberration correction technology in electron microscopy has enabled materials analysis on the atomic scale. This is made possible by precise arrangements of multipole electrodes and magnetic solenoids to compensate the aberrations inherent to any focusing element of an electron microscope. In this paper, we describe an alternative method to correct for the spherical aberration of the objective lens in scanning transmission electron microscopy (STEM) using a passive, nanofabricated diffractive optical element. This holographic device is installed in the probe forming aperture of a conventional electron microscope and can be designed to removemore » arbitrarily complex aberrations from the electron's wave front. In this work, we show a proof-of-principle experiment that demonstrates successful correction of the spherical aberration in STEM by means of such a grating corrector (GCOR). Our GCOR enables us to record aberration-corrected high-resolution high-angle annular dark field (HAADF-) STEM images, although yet without advancement in probe current and resolution. Finally, improvements in this technology could provide an economical solution for aberration-corrected high-resolution STEM in certain use scenarios.« less

  3. Aberration corrected STEM by means of diffraction gratings

    DOE PAGES

    Linck, Martin; Ercius, Peter A.; Pierce, Jordan S.; ...

    2017-06-12

    In the past 15 years, the advent of aberration correction technology in electron microscopy has enabled materials analysis on the atomic scale. This is made possible by precise arrangements of multipole electrodes and magnetic solenoids to compensate the aberrations inherent to any focusing element of an electron microscope. In this paper, we describe an alternative method to correct for the spherical aberration of the objective lens in scanning transmission electron microscopy (STEM) using a passive, nanofabricated diffractive optical element. This holographic device is installed in the probe forming aperture of a conventional electron microscope and can be designed to removemore » arbitrarily complex aberrations from the electron's wave front. In this work, we show a proof-of-principle experiment that demonstrates successful correction of the spherical aberration in STEM by means of such a grating corrector (GCOR). Our GCOR enables us to record aberration-corrected high-resolution high-angle annular dark field (HAADF-) STEM images, although yet without advancement in probe current and resolution. Finally, improvements in this technology could provide an economical solution for aberration-corrected high-resolution STEM in certain use scenarios.« less

  4. Assessment of nerve regeneration across nerve allografts treated with tacrolimus.

    PubMed

    Haisheng, Han; Songjie, Zuo; Xin, Li

    2008-01-01

    Although regeneration of nerve allotransplant is a major concern in the clinic, there have been few papers quantitatively assessing functional recovery of animals' nerve allografts in the long term. In this study, functional recovery, histopathological study, and immunohistochemistry changes of rat nerve allograft with FK506 were investigated up to 12 weeks without slaughtering. C57 and SD rats were used for transplantation. The donor's nerve was sliced and transplanted into the recipient. The sciatic nerve was epineurally sutured with 10-0 nylon. In total, 30 models of transplantation were performed and divided into 3 groups that were either treated with FK506 or not. Functional recovery of the grafted nerve was serially assessed by the pin click test, walking track analysis and electrophysiological evaluations. A histopathological study and immunohistochemistry study were done in the all of the models. Nerve allografts treated with FK506 have no immune rejection through 12 weeks. Sensibility had similarly improved in both isografts and allografts. There has been no difference in each graft. Walk track analysis demonstrates significant recovery of motor function of the nerve graft. No histological results of difference were found up to 12 weeks in each graft. In the rodent nerve graft model, FK506 prevented nerve allograft rejection across a major histocompatibility barrier. Sensory recovery seems to be superior to motor function. Nerve isograft and allograft treated with FK506 have no significant difference in function recovery, histopathological result, and immunohistochemistry changes.

  5. Aberration correction for charged particle lithography

    NASA Astrophysics Data System (ADS)

    Munro, Eric; Zhu, Xieqing; Rouse, John A.; Liu, Haoning

    2001-12-01

    At present, the throughput of projection-type charge particle lithography systems, such as PREVAIL and SCALPEL, is limited primarily by the combined effects of field curvature in the projection lenses and Coulomb interaction in the particle beam. These are fundamental physical limitations, inherent in charged particle optics, so there seems little scope for significantly improving the design of such systems, using conventional rotationally symmetric electron lenses. This paper explores the possibility of overcoming the field aberrations of round electron lense, by using a novel aberration corrector, proposed by Professor H. Rose of University of Darmstadt, called a hexapole planator. In this scheme, a set of round lenses is first used to simultaneously correct distortion and coma. The hexapole planator is then used to correct the field curvature and astigmatism, and to create a negative spherical aberration. The size of the transfer lenses around the planator can then be adjusted to zero the residual spherical aberration. In a way, an electron optical projection system is obtained that is free of all primary geometrical aberrations. In this paper, the feasibility of this concept has been studied with a computer simulation. The simulations verify that this scheme can indeed work, for both electrostatic and magnetic projection systems. Two design studies have been carried out. The first is for an electrostatic system that could be used for ion beam lithography, and the second is for a magnetic projection system for electron beam lithography. In both cases, designs have been achieved in which all primary third-order geometrical aberrations are totally eliminated.

  6. Aberration Compensation in Aplanatic Solid Immersion Lens Microscopy

    DTIC Science & Technology

    2013-11-08

    model and ray tracing software ( Zemax ) to understand how much aberrations are in the system and how much can be compensated by the DM. Subsequently...aberration. Table 2 shows the Zemax simulation on this particular case. With aberration compensation, the finest resolvable group is at 252 nm

  7. Nanofiber Nerve Guide for Peripheral Nerve Repair and Regeneration

    DTIC Science & Technology

    2016-04-01

    faster regeneration and functional recovery. Peripheral nerve injury is a common complication of complex tissue trauma and often results in significant...having poor regeneration overall, the areas of regenerating nerve tissue could often be found in sections of the nerve guide where luminal spaces of...conducted in this Aim also provided important insight into the NGC design parameters necessary to allow for maximum nerve tissue ingrowth and regeneration

  8. The role of great auricular-facial nerve neurorrhaphy in facial nerve damage

    PubMed Central

    Sun, Yan; Liu, Limei; Han, Yuechen; Xu, Lei; Zhang, Daogong; Wang, Haibo

    2015-01-01

    Background: Facial nerve is easy to be damaged, and there are many reconstructive methods for facial nerve reconstructive, such as facial nerve end to end anastomosis, the great auricular nerve graft, the sural nerve graft, or hypoglossal-facial nerve anastomosis. However, there is still little study about great auricular-facial nerve neurorrhaphy. The aim of the present study was to identify the role of great auricular-facial nerve neurorrhaphy and the mechanism. Methods: Rat models of facial nerve cut (FC), facial nerve end to end anastomosis (FF), facial-great auricular neurorrhaphy (FG), and control (Ctrl) were established. Apex nasi amesiality observation, electrophysiology and immunofluorescence assays were employed to investigate the function and mechanism. Results: In apex nasi amesiality observation, it was found apex nasi amesiality of FG group was partly recovered. Additionally, electrophysiology and immunofluorescence assays revealed that facial-great auricular neurorrhaphy could transfer nerve impulse and express AChR which was better than facial nerve cut and worse than facial nerve end to end anastomosis. Conclusions: The present study indicated that great auricular-facial nerve neurorrhaphy is a substantial solution for facial lesion repair, as it is efficiently preventing facial muscles atrophy by generating neurotransmitter like ACh. PMID:26550216

  9. [CT study on the development of facial nerve canal in children].

    PubMed

    Li, J M; Xu, W B; Zhong, J W; Wu, H Y; Dai, W C

    2016-10-07

    Objective: To assess the characteristics of facial nerve canal between normal anatomy and dysplasia of children in different ages. Methods: A total of 492 health ears were divided into six groups, neonatal group (<1 m , n =42), infancy group(1 m-1 y, n =106), toddler group(1-3 y, n =102), preschool group (3-6 y, n =100), school group(6-10 y, n =60)and adolescent group (10-14 y, n =82). The length and diameter of facial nerve canal and that angles of first and second genu were measured with CT in each group. Results: ①The lengths of facial nerve canal in neonatal and infancy group were shorter than other four groups, especially in the mastoid segments of facial nerve canal. The lengths of mastoid segments in neonatal, infancy, toddler, preschool, school and adolescent groups were 5.03±0.84, 6.25±1.40, 8.34±1.38, 9.70±1.34, 10.84±1.41 and 12.17±1.83 mm, with P <0.05, respectively. After school age, the lengths of labyrinthine and tympanic segment grew slowly or developed completely ( P >0.05). ② The diameter of labyrinth and tympanic segment in neonatal group were narrower than other five groups ( P <0.05), but no significant difference among them in other groups ( P >0.05). ③The dysplasia of facial nerve canal were occurred on 978 locations. Among them, the percentage of dehiscence, aberrance, partially expanding and bifurcation were 72.9%(713/978), 5.1%(50/978), 18.9%(185/978) and 3.1%(30/978) respectively. The percentage of dehiscence in geniculate fossa segment was decreased significantly with age (neonatal group 85.7%(36/42), infancy group 59.4%(63/106), toddler group 39.2%(40/102), preschool group 33%(33/100), school group 30%(18/60)and adolescent group 26.8%(22/82), with P <0.05). Except the dehiscence of geniculate fossa and mastoid segment, there was no significant difference in the occurrence rate of the other variants ( P >O.05). Conclusions: The growth of length and dehiscence in labyrinth segment of facial nerve canal are significant in

  10. Rooting Out Aberrant Behavior in Training.

    ERIC Educational Resources Information Center

    Kokalis, Jerry, Jr.; Paquin, Dave

    1989-01-01

    Discusses aberrant, or disruptive, behavior in an industrial/business, classroom-based, instructor-led training setting. Three examples of aberrant behavior are described, typical case studies are provided for each, and preventive (long-term) and corrective (on-the-spot) strategies for dealing with the problems are discussed. (LRW)

  11. Nerve Blocks

    MedlinePlus

    ... turn off" a pain signal along a specific distribution of nerve. Imaging guidance may be used to place the needle in the most appropriate location for maximum benefit. A nerve block may allow a damaged nerve time to heal, provide temporary pain relief and help ...

  12. Human eyes do not need monochromatic aberrations for dynamic accommodation.

    PubMed

    Bernal-Molina, Paula; Marín-Franch, Iván; Del Águila-Carrasco, Antonio J; Esteve-Taboada, Jose J; López-Gil, Norberto; Kruger, Philip B; Montés-Micó, Robert

    2017-09-01

    To determine if human accommodation uses the eye's own monochromatic aberrations to track dynamic accommodative stimuli. Wavefront aberrations were measured while subjects monocularly viewed a monochromatic Maltese cross moving sinusoidally around 2D of accommodative demand with 1D amplitude at 0.2 Hz. The amplitude and phase (delay) of the accommodation response were compared to the actual vergence of the stimulus to obtain gain and temporal phase, calculated from wavefront aberrations recorded over time during experimental trials. The tested conditions were as follows: Correction of all the subject's aberrations except defocus (C); Correction of all the subject's aberrations except defocus and habitual second-order astigmatism (AS); Correction of all the subject's aberrations except defocus and odd higher-order aberrations (HOAs); Correction of all the subject's aberrations except defocus and even HOAs (E); Natural aberrations of the subject's eye, i.e., the adaptive-optics system only corrected the optical system's aberrations (N); Correction of all the subject's aberrations except defocus and fourth-order spherical aberration (SA). The correction was performed at 20 Hz and each condition was repeated six times in randomised order. Average gain (±2 standard errors of the mean) varied little across conditions; between 0.55 ± 0.06 (SA), and 0.62 ± 0.06 (AS). Average phase (±2 standard errors of the mean) also varied little; between 0.41 ± 0.02 s (E), and 0.47 ± 0.02 s (O). After Bonferroni correction, no statistically significant differences in gain or phase were found in the presence of specific monochromatic aberrations or in their absence. These results show that the eye's monochromatic aberrations are not necessary for accommodation to track dynamic accommodative stimuli. © 2017 The Authors. Ophthalmic and Physiological Optics published by John Wiley & Sons Ltd on behalf of College of Optometrists.

  13. Fibrolipomatous hamartoma of the inferior calcaneal nerve (Baxter nerve).

    PubMed

    Zeng, Rong; Frederick-Dyer, Katherine; Ferguson, N Lynn; Lewis, James; Fu, Yitong

    2012-09-01

    Fibrolipomatous hamartoma (FLH) is a rare, benign lesion of the peripheral nerves most frequently involving the median nerve and its digital branches (80 %). Pathognomonic MR features of FLH such as coaxial-cable-like appearance on axial planes and a spaghetti-like appearance on coronal planes have been described by Marom and Helms, obviating the need for diagnostic biopsy. We present a case of fibrolipomatous hamartoma of the inferior calcaneal nerve (Baxter nerve) with associated subcutaneous fat proliferation.

  14. Third-rank chromatic aberrations of electron lenses.

    PubMed

    Liu, Zhixiong

    2018-02-01

    In this paper the third-rank chromatic aberration coefficients of round electron lenses are analytically derived and numerically calculated by Mathematica. Furthermore, the numerical results are cross-checked by the differential algebraic (DA) method, which verifies that all the formulas for the third-rank chromatic aberration coefficients are completely correct. It is hoped that this work would be helpful for further chromatic aberration correction in electron microscopy. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Overlapping Mechanisms of Peripheral Nerve Regeneration and Angiogenesis Following Sciatic Nerve Transection

    PubMed Central

    Wang, Hongkui; Zhu, Hui; Guo, Qi; Qian, Tianmei; Zhang, Ping; Li, Shiying; Xue, Chengbin; Gu, Xiaosong

    2017-01-01

    Peripheral nervous system owns the ability of self-regeneration, mainly in its regenerative microenvironment including vascular network reconstruction. More recently, more attentions have been given to the close relationship between tissue regeneration and angiogenesis. To explore the overlap of molecular mechanisms and key regulation molecules between peripheral nerve regeneration and angiogenesis post peripheral nerve injury, integrative and bioinformatic analysis was carried out for microarray data of proximal stumps after sciatic nerve transection in SD rats. Nerve regeneration and angiogenesis were activated at 1 day immediately after sciatic nerve transection simultaneously. The more obvious changes of transcription regulators and canonical pathways suggested a phase transition between 1 and 4 days of both nerve regeneration and angiogenesis after sciatic nerve transection. Furthermore, 16 differentially expressed genes participated in significant biological processes of both nerve regeneration and angiogenesis, a few of which were validated by qPCR and immunofluorescent staining. It was demonstrated that STAT3, EPHB3, and Cdc42 co-expressed in Schwann cells and vascular endothelial cells to play a key role in regulation of nerve regeneration and angiogenesis simultaneously response to sciatic nerve transection. We provide a framework for understanding biological processes and precise molecular correlations between peripheral nerve regeneration and angiogenesis after peripheral nerve transection. Our work serves as an experimental basis and a valuable resource to further understand molecular mechanisms that define nerve injury-induced micro-environmental variation for achieving desired peripheral nerve regeneration. PMID:29085283

  16. Overlapping Mechanisms of Peripheral Nerve Regeneration and Angiogenesis Following Sciatic Nerve Transection.

    PubMed

    Wang, Hongkui; Zhu, Hui; Guo, Qi; Qian, Tianmei; Zhang, Ping; Li, Shiying; Xue, Chengbin; Gu, Xiaosong

    2017-01-01

    Peripheral nervous system owns the ability of self-regeneration, mainly in its regenerative microenvironment including vascular network reconstruction. More recently, more attentions have been given to the close relationship between tissue regeneration and angiogenesis. To explore the overlap of molecular mechanisms and key regulation molecules between peripheral nerve regeneration and angiogenesis post peripheral nerve injury, integrative and bioinformatic analysis was carried out for microarray data of proximal stumps after sciatic nerve transection in SD rats. Nerve regeneration and angiogenesis were activated at 1 day immediately after sciatic nerve transection simultaneously. The more obvious changes of transcription regulators and canonical pathways suggested a phase transition between 1 and 4 days of both nerve regeneration and angiogenesis after sciatic nerve transection. Furthermore, 16 differentially expressed genes participated in significant biological processes of both nerve regeneration and angiogenesis, a few of which were validated by qPCR and immunofluorescent staining. It was demonstrated that STAT3, EPHB3, and Cdc42 co-expressed in Schwann cells and vascular endothelial cells to play a key role in regulation of nerve regeneration and angiogenesis simultaneously response to sciatic nerve transection. We provide a framework for understanding biological processes and precise molecular correlations between peripheral nerve regeneration and angiogenesis after peripheral nerve transection. Our work serves as an experimental basis and a valuable resource to further understand molecular mechanisms that define nerve injury-induced micro-environmental variation for achieving desired peripheral nerve regeneration.

  17. The Distribution of Chromosomal Aberrations in Human Cells Predicted by a Generalized Time-Dependent Model of Radiation-Induced Formation of Aberrations

    NASA Technical Reports Server (NTRS)

    Ponomarev, Artem L.; George, K.; Cucinotta, F. A.

    2011-01-01

    New experimental data show how chromosomal aberrations for low- and high-LET radiation are dependent on DSB repair deficiencies in wild-type, AT and NBS cells. We simulated the development of chromosomal aberrations in these cells lines in a stochastic track-structure-dependent model, in which different cells have different kinetics of DSB repair. We updated a previously formulated model of chromosomal aberrations, which was based on a stochastic Monte Carlo approach, to consider the time-dependence of DSB rejoining. The previous version of the model had an assumption that all DSBs would rejoin, and therefore we called it a time-independent model. The chromosomal-aberrations model takes into account the DNA and track structure for low- and high-LET radiations, and provides an explanation and prediction of the statistics of rare and more complex aberrations. We compared the program-simulated kinetics of DSB rejoining to the experimentally-derived bimodal exponential curves of the DSB kinetics. We scored the formation of translocations, dicentrics, acentric and centric rings, deletions, and inversions. The fraction of DSBs participating in aberrations was studied in relation to the rejoining time. Comparisons of simulated dose dependence for simple aberrations to the experimental dose-dependence for HF19, AT and NBS cells will be made.

  18. Harmonic oscillator states in aberration optics

    NASA Technical Reports Server (NTRS)

    Wolf, Kurt Bernardo

    1993-01-01

    The states of the three-dimensional quantum harmonic oscillator classify optical aberrations of axis-symmetric systems due to the isomorphism between the two mathematical structures. Cartesian quanta and angular momentum classifications have their corresponding aberration classifications. The operation of concatenation of optical elements introduces a new operation between harmonic oscillator states.

  19. Electrophysiology of Cranial Nerve Testing: Spinal Accessory and Hypoglossal Nerves.

    PubMed

    Stino, Amro M; Smith, Benn E

    2018-01-01

    Multiple techniques have been developed for the electrodiagnostic evaluation of cranial nerves XI and XII. Each of these carries both benefits and limitations, with more techniques and data being available in the literature for spinal accessory than hypoglossal nerve evaluation. Spinal accessory and hypoglossal neuropathy are relatively uncommon cranial mononeuropathies that may be evaluated in the outpatient electrodiagnostic laboratory setting. A review of available literature using PubMed was conducted regarding electrodiagnostic technique in the evaluation of spinal accessory and hypoglossal nerves searching for both routine nerve conduction studies and repetitive nerve conduction studies. The review provided herein provides a resource by which clinical neurophysiologists may develop and implement clinical and research protocols for the evaluation of both of these lower cranial nerves in the outpatient setting.

  20. Routine exposure of recurrent laryngeal nerve in thyroid surgery can prevent nerve injury.

    PubMed

    Shen, Chenling; Xiang, Mingliang; Wu, Hao; Ma, Yan; Chen, Li; Cheng, Lan

    2013-06-15

    To determine the value of dissecting the recurrent laryngeal nerve during thyroid surgery with respect to preventing recurrent laryngeal nerve injury, we retrospectively analyzed clinical data from 5 344 patients undergoing thyroidectomy. Among these cases, 548 underwent dissection of the recurrent laryngeal nerve, while 4 796 did not. There were 12 cases of recurrent laryngeal nerve injury following recurrent laryngeal nerve dissection (injury rate of 2.2%) and 512 cases of recurrent laryngeal nerve injury in those not undergoing nerve dissection (injury rate of 10.7%). This difference remained statistically significant between the two groups in terms of type of thyroid disease, type of surgery, and number of surgeries. Among the 548 cases undergoing recurrent laryngeal nerve dissection, 128 developed anatomical variations of the recurrent laryngeal nerve (incidence rate of 23.4%), but no recurrent laryngeal nerve injury was found. In addition, the incidence of recurrent laryngeal nerve injury was significantly lower in patients with the inferior parathyroid gland and middle thyroid veins used as landmarks for locating the recurrent laryngeal nerve compared with those with the entry of the recurrent laryngeal nerve into the larynx as a landmark. These findings indicate that anatomical variations of the recurrent laryngeal nerve are common, and that dissecting the recurrent laryngeal nerve during thyroid surgery is an effective means of preventing nerve injury.

  1. Routine exposure of recurrent laryngeal nerve in thyroid surgery can prevent nerve injury★

    PubMed Central

    Shen, Chenling; Xiang, Mingliang; Wu, Hao; Ma, Yan; Chen, Li; Cheng, Lan

    2013-01-01

    To determine the value of dissecting the recurrent laryngeal nerve during thyroid surgery with respect to preventing recurrent laryngeal nerve injury, we retrospectively analyzed clinical data from 5 344 patients undergoing thyroidectomy. Among these cases, 548 underwent dissection of the recurrent laryngeal nerve, while 4 796 did not. There were 12 cases of recurrent laryngeal nerve injury following recurrent laryngeal nerve dissection (injury rate of 2.2%) and 512 cases of recurrent laryngeal nerve injury in those not undergoing nerve dissection (injury rate of 10.7%). This difference remained statistically significant between the two groups in terms of type of thyroid disease, type of surgery, and number of surgeries. Among the 548 cases undergoing recurrent laryngeal nerve dissection, 128 developed anatomical variations of the recurrent laryngeal nerve (incidence rate of 23.4%), but no recurrent laryngeal nerve injury was found. In addition, the incidence of recurrent laryngeal nerve injury was significantly lower in patients with the inferior parathyroid gland and middle thyroid veins used as landmarks for locating the recurrent laryngeal nerve compared with those with the entry of the recurrent laryngeal nerve into the larynx as a landmark. These findings indicate that anatomical variations of the recurrent laryngeal nerve are common, and that dissecting the recurrent laryngeal nerve during thyroid surgery is an effective means of preventing nerve injury. PMID:25206452

  2. A collagen-based nerve guide conduit for peripheral nerve repair: an electrophysiological study of nerve regeneration in rodents and nonhuman primates.

    PubMed

    Archibald, S J; Krarup, C; Shefner, J; Li, S T; Madison, R D

    1991-04-22

    When a peripheral nerve is severed and left untreated, the most likely result is the formation of an endbulb neuroma; this tangled mass of disorganized nerve fibers blocks functional recovery following nerve injury. Although there are several different approaches for promoting nerve repair, which have been greatly refined over recent years, the clinical results of peripheral nerve repair remain very disappointing. In this paper we compare the results of a collagen nerve guide conduit to the more standard clinical procedure of nerve autografting to promote repair of transected peripheral nerves in rats and nonhuman primates. In rats, we tested recovery from sciatic nerve transection and repair by 1) direct microsurgical suture, 2) 4 mm autograft, or 3) entubulation repair with collagen-based nerve guide conduits. Evoked muscle action potentials (MAP) were recorded from the gastrocnemius muscle at 4 and 12 weeks following sciatic nerve transection. At 4 weeks the repair group of direct suture demonstrated a significantly greater MAP, compared to the other surgical repair groups. However, at 12 weeks all four surgical repair groups displayed similar levels of recovery of the motor response. In six adult male Macaca fascicularis monkeys the median nerve was transected 2 cm above the wrist and repaired by either a 4 mm nerve autograft or a collagen-based nerve guide conduit leaving a 4 mm gap between nerve ends. Serial studies of motor and sensory fibers were performed by recording the evoked MAP from the abductor pollicis brevis muscle (APB) and the sensory action potential (SAP) evoked by stimulation of digital nerves (digit II), respectively, up to 760 days following surgery. Evoked muscle responses returned to normal baseline levels in all cases. Statistical analysis of the motor responses, as judged by the slope of the recovery curves, indicated a significantly more rapid rate of recovery for the nerve guide repair group. The final level of recovery of the MAP

  3. [Facial nerve neurinomas].

    PubMed

    Sokołowski, Jacek; Bartoszewicz, Robert; Morawski, Krzysztof; Jamróz, Barbara; Niemczyk, Kazimierz

    2013-01-01

    Evaluation of diagnostic, surgical technique, treatment results facial nerve neurinomas and its comparison with literature was the main purpose of this study. Seven cases of patients (2005-2011) with facial nerve schwannomas were included to retrospective analysis in the Department of Otolaryngology, Medical University of Warsaw. All patients were assessed with history of the disease, physical examination, hearing tests, computed tomography and/or magnetic resonance imaging, electronystagmography. Cases were observed in the direction of potential complications and recurrences. Neurinoma of the facial nerve occurred in the vertical segment (n=2), facial nerve geniculum (n=1) and the internal auditory canal (n=4). The symptoms observed in patients were analyzed: facial nerve paresis (n=3), hearing loss (n=2), dizziness (n=1). Magnetic resonance imaging and computed tomography allowed to confirm the presence of the tumor and to assess its staging. Schwannoma of the facial nerve has been surgically removed using the middle fossa approach (n=5) and by antromastoidectomy (n=2). Anatomical continuity of the facial nerve was achieved in 3 cases. In the twelve months after surgery, facial nerve paresis was rated at level II-III° HB. There was no recurrence of the tumor in radiological observation. Facial nerve neurinoma is a rare tumor. Currently surgical techniques allow in most cases, the radical removing of the lesion and reconstruction of the VII nerve function. The rate of recurrence is low. A tumor of the facial nerve should be considered in the differential diagnosis of nerve VII paresis. Copyright © 2013 Polish Otorhinolaryngology - Head and Neck Surgery Society. Published by Elsevier Urban & Partner Sp. z.o.o. All rights reserved.

  4. Distortion of ultrashort pulses caused by aberrations

    NASA Astrophysics Data System (ADS)

    Horváth, Z. L.; Kovács, A. P.; Bor, Zs.

    The effect of the primary wave aberrations (spherical aberration, astigmatism and coma) on ultrashort pulses is studied by the Nijboer-Zernike theory. The results of the geometrical and the wave optical treatments are compared.

  5. Aberration-free intraocular lenses - What does this really mean?

    PubMed

    Langenbucher, Achim; Schröder, Simon; Cayless, Alan; Eppig, Timo

    2017-09-01

    So-called aberration-free intraocular lenses (IOLs) are well established in modern cataract surgery. Usually, they are designed to perfectly refract a collimated light beam onto the focal point. We show how much aberration can be expected with such an IOL in a convergent light beam such as that found anterior to the human cornea. Additionally, the aberration in a collimated beam is estimated for an IOL that has no aberrations in the convergent beam. The convergent beam is modelled as the pencil of rays corresponding to the spherical wavefront resulting from a typical corneal power of 43m -1 . The IOLs are modelled as infinitely thin phase plates with 20m -1 optical power placed 5mm behind the cornea. Their aberrations are reported in terms of optical path length difference and longitudinal spherical aberration (LSA) of the marginal rays, as well as nominal spherical aberration (SA) calculated based on a Zernike representation of the wavefront-error at the corneal plane within a 6mm aperture. The IOL designed to have no aberrations in a collimated light beam has an optical path length difference of -1.8μm, and LSA of 0.15m -1 in the convergent beam of a typical eye. The corresponding nominal SA is 0.065μm. The IOL designed to have no aberrations in a convergent light beam has an optical path length difference of 1.8μm, and LSA of -0.15m -1 in the collimated beam. An IOL designed to have no aberrations in a collimated light beam will increase the SA of a patient's eye after implantation. Copyright © 2017. Published by Elsevier GmbH.

  6. Optic Nerve Decompression

    MedlinePlus

    ... Nerve Decompression Dacryocystorhinostomy (DCR) Disclosure Statement Printer Friendly Optic Nerve Decompression John Lee, MD Introduction Optic nerve decompression is a surgical procedure aimed at ...

  7. Effect of aberrations in human eye on contrast sensitivity function

    NASA Astrophysics Data System (ADS)

    Quan, Wei; Wang, Feng-lin; Wang, Zhao-qi

    2011-06-01

    The quantitative analysis of the effect of aberrations in human eye on vision has important clinical value in the correction of aberrations. The wave-front aberrations of human eyes were measured with the Hartmann-Shack wave-front sensor and modulation transfer function (MTF) was computed from the wave-front aberrations. Contrast sensitivity function (CSF) was obtained from MTF and the retinal aerial image modulation (AIM). It is shown that the 2nd, 3rd, 4th, 5th, 6th Zernike aberrations deteriorate contrast sensitivity function. When the 2nd, 3rd, 4th, 5th, 6th Zernike aberrations are corrected high contrast sensitivity function can be obtained.

  8. Detecting independent and recurrent copy number aberrations using interval graphs.

    PubMed

    Wu, Hsin-Ta; Hajirasouliha, Iman; Raphael, Benjamin J

    2014-06-15

    Somatic copy number aberrations SCNAS: are frequent in cancer genomes, but many of these are random, passenger events. A common strategy to distinguish functional aberrations from passengers is to identify those aberrations that are recurrent across multiple samples. However, the extensive variability in the length and position of SCNA: s makes the problem of identifying recurrent aberrations notoriously difficult. We introduce a combinatorial approach to the problem of identifying independent and recurrent SCNA: s, focusing on the key challenging of separating the overlaps in aberrations across individuals into independent events. We derive independent and recurrent SCNA: s as maximal cliques in an interval graph constructed from overlaps between aberrations. We efficiently enumerate all such cliques, and derive a dynamic programming algorithm to find an optimal selection of non-overlapping cliques, resulting in a very fast algorithm, which we call RAIG (Recurrent Aberrations from Interval Graphs). We show that RAIG outperforms other methods on simulated data and also performs well on data from three cancer types from The Cancer Genome Atlas (TCGA). In contrast to existing approaches that employ various heuristics to select independent aberrations, RAIG optimizes a well-defined objective function. We show that this allows RAIG to identify rare aberrations that are likely functional, but are obscured by overlaps with larger passenger aberrations. http://compbio.cs.brown.edu/software. © The Author 2014. Published by Oxford University Press.

  9. Linear phase conjugation for atmospheric aberration compensation

    NASA Astrophysics Data System (ADS)

    Grasso, Robert J.; Stappaerts, Eddy A.

    1998-01-01

    Atmospheric induced aberrations can seriously degrade laser performance, greatly affecting the beam that finally reaches the target. Lasers propagated over any distance in the atmosphere suffer from a significant decrease in fluence at the target due to these aberrations. This is especially so for propagation over long distances. It is due primarily to fluctuations in the atmosphere over the propagation path, and from platform motion relative to the intended aimpoint. Also, delivery of high fluence to the target typically requires low beam divergence, thus, atmospheric turbulence, platform motion, or both results in a lack of fine aimpoint control to keep the beam directed at the target. To improve both the beam quality and amount of laser energy delivered to the target, Northrop Grumman has developed the Active Tracking System (ATS); a novel linear phase conjugation aberration compensation technique. Utilizing a silicon spatial light modulator (SLM) as a dynamic wavefront reversing element, ATS undoes aberrations induced by the atmosphere, platform motion or both. ATS continually tracks the target as well as compensates for atmospheric and platform motion induced aberrations. This results in a high fidelity, near-diffraction limited beam delivered to the target.

  10. Wave aberrations in rhesus monkeys with vision-induced ametropias

    PubMed Central

    Ramamirtham, Ramkumar; Kee, Chea-su; Hung, Li-Fang; Qiao-Grider, Ying; Huang, Juan; Roorda, Austin; Smith, Earl L.

    2007-01-01

    The purpose of this study was to investigate the relationship between refractive errors and high-order aberrations in infant rhesus monkeys. Specifically, we compared the monochromatic wave aberrations measured with a Shack-Hartman wavefront sensor between normal monkeys and monkeys with vision-induced refractive errors. Shortly after birth, both normal monkeys and treated monkeys reared with optically induced defocus or form deprivation showed a decrease in the magnitude of high-order aberrations with age. However, the decrease in aberrations was typically smaller in the treated animals. Thus, at the end of the lens-rearing period, higher than normal amounts of aberrations were observed in treated eyes, both hyperopic and myopic eyes and treated eyes that developed astigmatism, but not spherical ametropias. The total RMS wavefront error increased with the degree of spherical refractive error, but was not correlated with the degree of astigmatism. Both myopic and hyperopic treated eyes showed elevated amounts of coma and trefoil and the degree of trefoil increased with the degree of spherical ametropia. Myopic eyes also exhibited a much higher prevalence of positive spherical aberration than normal or treated hyperopic eyes. Following the onset of unrestricted vision, the amount of high-order aberrations decreased in the treated monkeys that also recovered from the experimentally induced refractive errors. Our results demonstrate that high-order aberrations are influenced by visual experience in young primates and that the increase in high-order aberrations in our treated monkeys appears to be an optical byproduct of the vision-induced alterations in ocular growth that underlie changes in refractive error. The results from our study suggest that the higher amounts of wave aberrations observed in ametropic humans are likely to be a consequence, rather than a cause, of abnormal refractive development. PMID:17825347

  11. Aberrations in stimulated emission depletion (STED) microscopy

    NASA Astrophysics Data System (ADS)

    Antonello, Jacopo; Burke, Daniel; Booth, Martin J.

    2017-12-01

    Like all methods of super-resolution microscopy, stimulated emission depletion (STED) microscopy can suffer from the effects of aberrations. The most important aspect of a STED microscope is that the depletion focus maintains a minimum, ideally zero, intensity point that is surrounded by a region of higher intensity. It follows that aberrations that cause a non-zero value of this minimum intensity are the most detrimental, as they inhibit fluorescence emission even at the centre of the depletion focus. We present analysis that elucidates the nature of these effects in terms of the different polarisation components at the focus for two-dimensional and three-dimensional STED resolution enhancement. It is found that only certain low-order aberration modes can affect the minimum intensity at the Gaussian focus. This has important consequences for the design of adaptive optics aberration correction systems.

  12. 3D resolved mapping of optical aberrations in thick tissues

    PubMed Central

    Zeng, Jun; Mahou, Pierre; Schanne-Klein, Marie-Claire; Beaurepaire, Emmanuel; Débarre, Delphine

    2012-01-01

    We demonstrate a simple method for mapping optical aberrations with 3D resolution within thick samples. The method relies on the local measurement of the variation in image quality with externally applied aberrations. We discuss the accuracy of the method as a function of the signal strength and of the aberration amplitude and we derive the achievable resolution for the resulting measurements. We then report on measured 3D aberration maps in human skin biopsies and mouse brain slices. From these data, we analyse the consequences of tissue structure and refractive index distribution on aberrations and imaging depth in normal and cleared tissue samples. The aberration maps allow the estimation of the typical aplanetism region size over which aberrations can be uniformly corrected. This method and data pave the way towards efficient correction strategies for tissue imaging applications. PMID:22876353

  13. Reconstruction of peripheral nerves using acellular nerve grafts with implanted cultured Schwann cells.

    PubMed

    Frerichs, Onno; Fansa, Hisham; Schicht, Christoph; Wolf, Gerald; Schneider, Wolfgang; Keilhoff, Gerburg

    2002-01-01

    The bridging of nerve gaps is still one of the major problems in peripheral nerve surgery. The present experiment describes our attempt to engineer different biologic nerve grafts in a rat sciatic nerve model: cultured isogenic Schwann cells were implanted into 2-cm autologous acellular nerve grafts or autologous predegenerated nerve grafts. Autologous nerve grafts and predegenerated or acellular nerve grafts without implanted Schwann cells served as controls. The regenerated nerves were assessed histologically and morphometrically after 6 weeks. Predegenerated grafts showed results superior in regard to axon count and histologic appearance in comparison to standard grafts and acellular grafts. The acellular nerve grafts showed the worst histologic picture, but axon counts were in the range of standard grafts. The implantation of Schwann cells did not yield significant improvements in any group. In conclusion, the status of activation of Schwann cells and the stadium of Wallerian degeneration in a nerve graft might be key factors for regeneration, rather than total number of Schwann cells. Predegenerated nerve grafts are therefore superior to standard grafts in the rat model. Acellular grafts are able to bridge nerve gaps of up to 2 cm in the rat model, but even the addition of cultivated Schwann cells did not lead to results as good as in the group with autologous nerve grafts. Copyright 2002 Wiley-Liss, Inc. MICROSURGERY 22:311-315 2002

  14. Primary aberrations in focused radially polarized vortex beams

    NASA Astrophysics Data System (ADS)

    Biss, David P.; Brown, T. G.

    2004-02-01

    We study the effect of primary aberrations on the 3-D polarization of the electric field in a focused lowest order radially polarized beam. A full vector diffraction treatment of the focused beams is used. Attention is given to the effects of primary spherical, astigmatic, and comatic aberrations on the local polarization, Strehl ratio, and aberration induced degradation of the longitudinal field at focus

  15. The Art of Optical Aberrations

    NASA Astrophysics Data System (ADS)

    Wylde, Clarissa Eileen Kenney

    Art and optics are inseparable. Though seemingly opposite disciplines, the combination of art and optics has significantly impacted both culture and science as they are now known. As history has run its course, in the sciences, arts, and their fruitful combinations, optical aberrations have proved to be a problematic hindrance to progress. In an effort to eradicate aberrations the simple beauty of these aberrational forms has been labeled as undesirable and discarded. Here, rather than approach aberrations as erroneous, these beautiful forms are elevated to be the photographic subject in a new body of work, On the Bright Side. Though many recording methods could be utilized, this work was composed on classic, medium-format, photographic film using white-light, Michelson interferometry. The resulting images are both a representation of the true light rays that interacted on the distorted mirror surfaces (data) and the artist's compositional eye for what parts of the interferogram are chosen and displayed. A detailed description of the captivating interdisciplinary procedure is documented and presented alongside the final artwork, CCD digital reference images, and deformable mirror contour maps. This alluring marriage between the arts and sciences opens up a heretofore minimally explored aspect of the inextricable art-optics connection. It additionally provides a fascinating new conversation on the importance of light and optics in photographic composition.

  16. Population dynamics of aberrant chromosome 1 in mice.

    PubMed

    Sabantsev, I; Spitsin, O; Agulnik, S; Ruvinsky, A

    1993-05-01

    Natural populations of two semispecies of house mouse, Mus musculus domesticus and M.m. musculus, were found to be polymorphic for an aberrant chromosome 1 bearing a large inserted block of homogeneously staining heterochromatin. Strong meiotic drive for the aberrant chromosome from M.m. musculus was previously observed in heterozygous female mice. There are at least three meiotic drive levels determined by different allelic variants of distorter. Homozygotes had low viability and females showed low fertility. Both homo- and heterozygous males had normal fertility and their segregation patterns did not deviate from normal. Computer simulations were performed of the dynamics of aberrant chromosome 1 in demes and populations. The data demonstrate that a spontaneous mutation (inversion) of an aberrant chromosome 1, once arisen, has a high probability of spreading in a population at high coefficients of meiotic drive and migration. In the long-term, the population attains a stationary state which is determined by the drive level and migration intensity. The state of stable genotypic equilibrium is independent of deme and population size, as well as of the initial concentration of the aberrant chromosome. As populations initially polymorphic for the distorters approach the stationary state, the stronger distorter is eliminated. The frequencies of the aberrant chromosome determined by computer analysis agree well with those obtained for the studied Asian M.m. musculus populations. The evolutionary pathways for the origin and fixation of the aberrant chromosome in natural populations are considered.

  17. Aberration design of zoom lens systems using thick lens modules.

    PubMed

    Zhang, Jinkai; Chen, Xiaobo; Xi, Juntong; Wu, Zhuoqi

    2014-12-20

    A systematic approach for the aberration design of a zoom lens system using a thick lens module is presented. Each component is treated as a thick lens module at the beginning of the design. A thick lens module refers to a thick lens component with a real lens structure, like lens materials, lens curvatures, lens thicknesses, and lens interval distances. All nine third-order aberrations of a thick lens component are considered during the design. The relationship of component aberrations in different zoom positions can be approximated from the aberration shift. After minimizing the aberrations of the zoom lens system, the nine third-order aberrations of every lens component can be determined. Then the thick lens structure of every lens component can be determined after optimization according to their first-order properties and third-order aberration targets. After a third optimization for minimum practical third-order aberrations of a zoom lens system, the aberration design using the thick lens module is complete, which provides a practical zoom lens system with thick lens structures. A double-sided telecentric zoom lens system is designed using the thick lens module in this paper, which shows that this method is practical for zoom lens design.

  18. Radial nerve palsy

    PubMed Central

    Bumbasirevic, Marko; Palibrk, Tomislav; Lesic, Aleksandar; Atkinson, Henry DE

    2016-01-01

    As a result of its proximity to the humeral shaft, as well as its long and tortuous course, the radial nerve is the most frequently injured major nerve in the upper limb, with its close proximity to the bone making it vulnerable when fractures occur. Injury is most frequently sustained during humeral fracture and gunshot injuries, but iatrogenic injuries are not unusual following surgical treatment of various other pathologies. Treatment is usually non-operative, but surgery is sometimes necessary, using a variety of often imaginative procedures. Because radial nerve injuries are the least debilitating of the upper limb nerve injuries, results are usually satisfactory. Conservative treatment certainly has a role, and one of the most important aspects of this treatment is to maintain a full passive range of motion in all the affected joints. Surgical treatment is indicated in cases when nerve transection is obvious, as in open injuries or when there is no clinical improvement after a period of conservative treatment. Different techniques are used including direct suture or nerve grafting, vascularised nerve grafts, direct nerve transfer, tendon transfer, functional muscle transfer or the promising, newer treatment of biological therapy. Cite this article: Bumbasirevic M, Palibrk T, Lesic A, Atkinson HDE. Radial nerve palsy. EFORT Open Rev 2016;1:286-294. DOI: 10.1302/2058-5241.1.000028. PMID:28461960

  19. Vascular Entrapment of Both the Sciatic and Pudendal Nerves Causing Persistent Sciatica and Pudendal Neuralgia.

    PubMed

    Kale, Ahmet; Basol, Gulfem; Usta, Taner; Cam, Isa

    2018-04-24

    To demonstrate the laparoscopic approach to malformed branches of the vessels entrapping the nerves of the sacral plexus. A step-by-step explanation of the surgery using video (educative video) (Canadian Task force classification II). The university's Ethics Committee ruled that approval was not required for this video. Kocaeli Derince Education and Research Hospital, Kocaeli, Turkey. A 26-year-old patient who had failed medical therapy and presented with complaints of numbness and burning pain on the right side of her vagina and pain radiating to her lower limbs for a period of approximately 36 months. The peritoneum was incised along the external iliac vessels, and these vessels were separated from the iliopsoas muscle on the right side of the pelvis. The laparoscopic decompression of intrapelvic vascular entrapment was performed at 3 sites: the lumbosacral trunk, sciatic nerve, and pudendal nerve. The aberrant dilated veins were gently dissected from nerves, and then coagulated and cut with the LigaSure sealing device (Medtronic, Minneapolis, Minn). The operation was completed successfully with no complications, and the patient was discharged from the hospital 24 hours after the operation. At a 6-month follow-up, she reported complete resolution of dyspareunia and sciatica (visual analog scale score 1 of 10). A less well-known cause of chronic pelvic pain is compression of the sacral plexus by dilated or malformed branches of the internal iliac vessels. Laparoscopic management of vascular entrapment of the sacral plexus has been described by Possover et al [1,2] and Lemos et al [3]. This procedure appears to be feasible and effective, but requires significant experience and familiarity with laparoscopy techniques and pelvic nerve anatomy. Copyright © 2018 American Association of Gynecologic Laparoscopists. Published by Elsevier Inc. All rights reserved.

  20. The fate of the oculomotor system in clinical bilateral anophthalmia.

    PubMed

    Bridge, Holly; Ragge, Nicola; Jenkinson, Ned; Cowey, Alan; Watkins, Kate E

    2012-05-01

    The interdependence of the development of the eye and oculomotor system during embryogenesis is currently unclear. The occurrence of clinical anophthalmia, where the globe fails to develop, permits us to study the effects this has on the development of the complex neuromuscular system controlling eye movements. In this study, we use very high-resolution T2-weighted imaging in five anophthalmic subjects to visualize the extraocular muscles and the cranial nerves that innervate them. The subjects differed in the presence or absence of the optic nerve, the abducens nerve, and the extraocular muscles, reflecting differences in the underlying disruption to the eye's morphogenetic pathway. The oculomotor nerve was present in all anophthalmic subjects and only slightly reduced in size compared to measurements in sighted controls. As might be expected, the presence of rudimentary eye-like structures in the socket appeared to correlate with development and persistence of the extraocular muscles in some cases. Our study supports in part the concept of an initial independence of muscle development, with its maintenance subject to the presence of these eye-like structures.

  1. Aberration of a negative ion beam caused by space charge effect.

    PubMed

    Miyamoto, K; Wada, S; Hatayama, A

    2010-02-01

    Aberrations are inevitable when the charged particle beams are extracted, accelerated, transmitted, and focused with electrostatic and magnetic fields. In this study, we investigate the aberration of a negative ion accelerator for a neutral beam injector theoretically, especially the spherical aberration caused by the negative ion beam expansion due to the space charge effect. The negative ion current density profiles with the spherical aberration are compared with those without the spherical aberration. It is found that the negative ion current density profiles in a log scale are tailed due to the spherical aberration.

  2. Electrophysiology of Cranial Nerve Testing: Trigeminal and Facial Nerves.

    PubMed

    Muzyka, Iryna M; Estephan, Bachir

    2018-01-01

    The clinical examination of the trigeminal and facial nerves provides significant diagnostic value, especially in the localization of lesions in disorders affecting the central and/or peripheral nervous system. The electrodiagnostic evaluation of these nerves and their pathways adds further accuracy and reliability to the diagnostic investigation and the localization process, especially when different testing methods are combined based on the clinical presentation and the electrophysiological findings. The diagnostic uniqueness of the trigeminal and facial nerves is their connectivity and their coparticipation in reflexes commonly used in clinical practice, namely the blink and corneal reflexes. The other reflexes used in the diagnostic process and lesion localization are very nerve specific and add more diagnostic yield to the workup of certain disorders of the nervous system. This article provides a review of commonly used electrodiagnostic studies and techniques in the evaluation and lesion localization of cranial nerves V and VII.

  3. [Blood-nerve barrier and peripheral nerve regeneration].

    PubMed

    Kanda, Takashi

    2013-01-01

    Blood-nerve barrier (BNB) restricts the movement of soluble mediators and leukocytes from the blood contents to the peripheral nervous system (PNS) parenchyma and thus maintains the endoneurial homeostasis. However, it interferes the supply of various neurotrophic factors from the blood constituents and stops the drainage of toxic substances out of the PNS parenchyma, resulting in the inhibition of peripheral nerve regeneration. If the manipulation of BNB function is possible, regeneration of peripheral nerve may be facilitated via the alteration of peripheral nerve microenvironment and ample supply of neurotrophic substances. A possible method to manipulate the BNB for therapeutic purposes is to modify the endothelial function using siRNAs, oligonucleotides and virus vectors. Another possible method is to modify BNB pericytes: small hydrophobic substances that can reach the pericyte membrane through the endothelial monolayer and strengthen the pericytic activity, including the release of various cytokines/chemokines that influence endothelial function, may also be useful as drug candidates to control the BNB function.

  4. Miconazole enhances nerve regeneration and functional recovery after sciatic nerve crush injury.

    PubMed

    Lin, Tao; Qiu, Shuai; Yan, Liwei; Zhu, Shuang; Zheng, Canbin; Zhu, Qingtang; Liu, Xiaolin

    2018-05-01

    Improving axonal outgrowth and remyelination is crucial for peripheral nerve regeneration. Miconazole appears to enhance remyelination in the central nervous system. In this study we assess the effect of miconazole on axonal regeneration using a sciatic nerve crush injury model in rats. Fifty Sprague-Dawley rats were divided into control and miconazole groups. Nerve regeneration and myelination were determined using histological and electrophysiological assessment. Evaluation of sensory and motor recovery was performed using the pinprick assay and sciatic functional index. The Cell Counting Kit-8 assay and Western blotting were used to assess the proliferation and neurotrophic expression of RSC 96 Schwann cells. Miconazole promoted axonal regrowth, increased myelinated nerve fibers, improved sensory recovery and walking behavior, enhanced stimulated amplitude and nerve conduction velocity, and elevated proliferation and neurotrophic expression of RSC 96 Schwann cells. Miconazole was beneficial for nerve regeneration and functional recovery after peripheral nerve injury. Muscle Nerve 57: 821-828, 2018. © 2017 Wiley Periodicals, Inc.

  5. Optic Nerve Disorders

    MedlinePlus

    The optic nerve is a bundle of more than 1 million nerve fibers that carry visual messages. You have one connecting ... retina) to your brain. Damage to an optic nerve can cause vision loss. The type of vision ...

  6. Axillary nerve injury.

    PubMed

    Perlmutter, G S

    1999-11-01

    Axillary nerve injury remains the most common peripheral nerve injury to affect the shoulder. It most often is seen after glenohumeral joint dislocation, proximal humerus fracture, or a direct blow to the deltoid muscle. Compression neuropathy has been reported to occur in the quadrilateral space syndrome, although the true pathophysiology of this disorder remains unclear. The axillary nerve is vulnerable during any operative procedure involving the inferior aspect of the shoulder and iatrogenic injury remains a serious complication of shoulder surgery. During the acute phase of injury, the shoulder should be rested, and when clinically indicated, a patient should undergo an extensive rehabilitation program emphasizing range of motion and strengthening of the shoulder girdle muscles. If no axillary nerve recovery is observed by 3 to 6 months after injury, surgical exploration may be indicated, especially if the mechanism of injury is consistent with nerve rupture. Patients who sustain injury to the axillary nerve have a variable prognosis for nerve recovery although return of function of the involved shoulder typically is good to excellent, depending on associated ligamentous or bony injury.

  7. Hydronephrosis by an Aberrant Renal Artery: A Case Report

    PubMed Central

    Park, Byoung Seok; Jeong, Taek Kyun; Ma, Seong Kwon; Kim, Soo Wan; Kim, Nam Ho; Choi, Ki Chul; Jeong, Yong Yeon

    2003-01-01

    Ureteropelvic junction obstruction is usually intrinsic and is most common in children. Aberrant renal arteries are present in about 30% of individuals. Aberrant renal arteries to the inferior pole cross anteriorly to the ureter and may cause hydronephrosis. To the best of our knowledge, although there are some papers about aberrant renal arteries producing ureteropelvic junction obstruction, there is no report of a case which is diagnosed by the new modalities, such as computed tomography angiogram (CTA) or magnetic resonance angiogram (MRA). We describe a 36-year-old woman with right hydronephrosis. Kidney ultrasonogram and excretory urogram revealed right hydronephrosis. CTA and MRA clearly displayed an aberrant renal artery and hydronephrosis. The patient underwent surgical exploration. For the evaluation of hydronephrosis by an aberrant renal artery, use of CTA and MRA is advocated. PMID:12760271

  8. Permanent nerve damage from inferior alveolar nerve blocks: a current update.

    PubMed

    Pogrel, M Anthony

    2012-10-01

    Permanent nerve involvement has been reported following inferior alveolar nerve blocks. This study provides an update on cases reported to one unit in the preceding six years. Lidocaine was associated with 25 percent of cases, articaine with 33 percent of cases, and prilocaine with 34 percent of cases. It does appear that inferior alveolar nerve blocks can cause permanent nerve damage with any local anesthetic, but the incidences may vary.

  9. Ocular higher-order aberrations in a school children population.

    PubMed

    Papamastorakis, George; Panagopoulou, Sophia; Tsilimbaris, Militadis K; Pallikaris, Ioannis G; Plainis, Sotiris

    2015-01-01

    The primary objective of the study was to explore the statistics of ocular higher-order aberrations in a population of primary and secondary school children. A sample of 557 children aged 10-15 years were selected from two primary and two secondary schools in Heraklion, Greece. Children were classified by age in three subgroups: group I (10.7±0.5 years), group II (12.4±0.5 years) and group III (14.5±0.5 years). Ocular aberrations were measured using a wavefront aberrometer (COAS, AMO Wavefront Sciences, USA) at mesopic light levels (illuminance at cornea was 4lux). Wavefront analysis was achieved for a 5mm pupil. Statistical analysis was carried out for the right eye only. The average coefficient of most high-order aberrations did not differ from zero with the exception of vertical (0.076μm) and horizontal (0.018μm) coma, oblique trefoil (-0.055μm) and spherical aberration (0.018μm). The most prominent change between the three groups was observed for the spherical aberration, which increased from 0.007μm (SE 0.005) in group I to 0.011μm (SE 0.004) in group II and 0.030μm (SE 0.004) in group III. Significant differences were also found for the oblique astigmatism and the third-order coma aberrations. Differences in the low levels of ocular spherical aberration in young children possibly reflect differences in lenticular spherical aberration and relate to the gradient refractive index of the lens. The evaluation of spherical aberration at certain stages of eye growth may help to better understand the underlying mechanisms of myopia development. Copyright © 2014 Spanish General Council of Optometry. Published by Elsevier Espana. All rights reserved.

  10. Ocular higher-order aberrations in a school children population

    PubMed Central

    Papamastorakis, George; Panagopoulou, Sophia; Tsilimbaris, Militadis K.; Pallikaris, Ioannis G.; Plainis, Sotiris

    2014-01-01

    Purpose The primary objective of the study was to explore the statistics of ocular higher-order aberrations in a population of primary and secondary school children. Methods A sample of 557 children aged 10–15 years were selected from two primary and two secondary schools in Heraklion, Greece. Children were classified by age in three subgroups: group I (10.7 ± 0.5 years), group II (12.4 ± 0.5 years) and group III (14.5 ± 0.5 years). Ocular aberrations were measured using a wavefront aberrometer (COAS, AMO Wavefront Sciences, USA) at mesopic light levels (illuminance at cornea was 4 lux). Wavefront analysis was achieved for a 5 mm pupil. Statistical analysis was carried out for the right eye only. Results The average coefficient of most high-order aberrations did not differ from zero with the exception of vertical (0.076 μm) and horizontal (0.018 μm) coma, oblique trefoil (−0.055 μm) and spherical aberration (0.018 μm). The most prominent change between the three groups was observed for the spherical aberration, which increased from 0.007 μm (SE 0.005) in group I to 0.011 μm (SE 0.004) in group II and 0.030 μm (SE 0.004) in group III. Significant differences were also found for the oblique astigmatism and the third-order coma aberrations. Conclusions Differences in the low levels of ocular spherical aberration in young children possibly reflect differences in lenticular spherical aberration and relate to the gradient refractive index of the lens. The evaluation of spherical aberration at certain stages of eye growth may help to better understand the underlying mechanisms of myopia development. PMID:25288226

  11. The vestibulocochlear nerve (VIII).

    PubMed

    Benoudiba, F; Toulgoat, F; Sarrazin, J-L

    2013-10-01

    The vestibulocochlear nerve (8th cranial nerve) is a sensory nerve. It is made up of two nerves, the cochlear, which transmits sound and the vestibular which controls balance. It is an intracranial nerve which runs from the sensory receptors in the internal ear to the brain stem nuclei and finally to the auditory areas: the post-central gyrus and superior temporal auditory cortex. The most common lesions responsible for damage to VIII are vestibular Schwannomas. This report reviews the anatomy and various investigations of the nerve. Copyright © 2013. Published by Elsevier Masson SAS.

  12. Sensation, mechanoreceptor, and nerve fiber function after nerve regeneration.

    PubMed

    Krarup, Christian; Rosén, Birgitta; Boeckstyns, Michel; Ibsen Sørensen, Allan; Lundborg, Göran; Moldovan, Mihai; Archibald, Simon J

    2017-12-01

    Sensation is essential for recovery after peripheral nerve injury. However, the relationship between sensory modalities and function of regenerated fibers is uncertain. We have investigated the relationships between touch threshold, tactile gnosis, and mechanoreceptor and sensory fiber function after nerve regeneration. Twenty-one median or ulnar nerve lesions were repaired by a collagen nerve conduit or direct suture. Quantitative sensory hand function and sensory conduction studies by near-nerve technique, including tactile stimulation of mechanoreceptors, were followed for 2 years, and results were compared to noninjured hands. At both repair methods, touch thresholds at the finger tips recovered to 81 ± 3% and tactile gnosis only to 20 ± 4% (p < 0.001) of control. The sensory nerve action potentials (SNAPs) remained dispersed and areas recovered to 23 ± 2% and the amplitudes only to 7 ± 1% (P < 0.001). The areas of SNAPs after tactile stimulation recovered to 61 ± 11% and remained slowed. Touch sensation correlated with SNAP areas (p < 0.005) and was negatively related to the prolongation of tactile latencies (p < 0.01); tactile gnosis was not related to electrophysiological parameters. The recovered function of regenerated peripheral nerve fibers and reinnervated mechanoreceptors may differentially influence recovery of sensory modalities. Touch was affected by the number and function of regenerated fibers and mechanoreceptors. In contrast, tactile gnosis depends on the input and plasticity of the central nervous system (CNS), which may explain the absence of a direct relation between electrophysiological parameters and poor recovery. Dispersed maturation of sensory nerve fibers with desynchronized inputs to the CNS also contributes to the poor recovery of tactile gnosis. Ann Neurol 2017. Ann Neurol 2017;82:940-950. © 2017 American Neurological Association.

  13. Non-recurrent laryngeal nerve with a coexisting contralateral nerve demonstrating extralaryngeal branching.

    PubMed

    Constable, James D; Bathala, Srinivasalu; Ahmed, Jacob J; McGlashan, Julian A

    2017-03-17

    Non-recurrence and extralaryngeal branching are 2 of the more frequently encountered anomalies of the recurrent laryngeal nerve. If not anticipated intraoperatively, these abnormalities can put the nerve at risk, with subsequent vocal cord palsy. It is therefore important to report on and understand these abnormalities. We present a unique case of a non-recurrent laryngeal nerve with a coexisting contralateral nerve demonstrating extralaryngeal branching. This case allows us to demonstrate the importance of arteria lusoria in head and neck surgery, and to conclude that non-recurrence and extralaryngeal branching can occur separately within individual nerves in the same patient. The case also highlights the importance of a systematic intraoperative approach to the identification of every recurrent laryngeal nerve, especially in bilateral procedures having already exposed an anomalous nerve on one side. 2017 BMJ Publishing Group Ltd.

  14. [Glaucoma and optic nerve drusen: Limitations of optic nerve head OCT].

    PubMed

    Poli, M; Colange, J; Goutagny, B; Sellem, E

    2017-09-01

    Optic nerve head drusen are congenital calcium deposits located in the prelaminar section of the optic nerve head. Their association with visual field defects has been classically described, but the diagnosis of glaucoma is not easy in these cases of altered optic nerve head anatomy. We describe the case of a 67-year-old man with optic nerve head drusen complicated by glaucoma, which was confirmed by visual field and OCT examination of the peripapillary retinal nerve fiber layer (RNFL), but the measurement of the minimum distance between the Bruch membrane opening and the internal limiting membrane (minimum rim width, BMO-MRW) by OCT was normal. OCT of the BMO-MRW is a new diagnostic tool for glaucoma. Superficial optic nerve head drusen, which are found between the internal limiting membrane and the Bruch's membrane opening, overestimate the value of this parameter. BMO-MRW measurement is not adapted to cases of optic nerve head drusen and can cause false-negative results for this parameter, and the diagnosis of glaucoma in this case should be based on other parameters such as the presence of a fascicular defect in the retinal nerve fibers, RNFL or macular ganglion cell complex thinning, as well as visual field data. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  15. Immediate versus delayed primary nerve repair in the rabbit sciatic nerve

    PubMed Central

    Piskin, Ahmet; Altunkaynak, Berrin Zühal; Çιtlak, Atilla; Sezgin, Hicabi; Yazιcι, Ozgür; Kaplan, Süleyman

    2013-01-01

    It is well known that peripheral nerve injury should be treated immediately in the clinic, but in some instances, repair can be delayed. This study investigated the effects of immediate versus delayed (3 days after injury) neurorrhaphy on repair of transected sciatic nerve in New Zealand rabbits using stereological, histomorphological and biomechanical methods. At 8 weeks after immediate and delayed neurorrhaphy, axon number and area in the sciatic nerve, myelin sheath and epineurium thickness, Schwann cell morphology, and the mechanical property of nerve fibers did not differ obviously. These results indicate that delayed neurorrhaphy do not produce any deleterious effect on sciatic nerve repair. PMID:25206663

  16. Generalized Alvarez lens for correction of laser aberrations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    LaFortune, K N

    2004-12-02

    The Alvarez lens (US Patent No. 3,305,294 [1]) is a compact aberration corrector. The original design emphasized in the patent consists of a pair of adjacent optical elements that provide a variable focus. A lens system with a variable effective focal length is nothing new. Such systems are widely used in cameras, for example. It is the compactness and simplicity of operation that is the key advantage of the Alvarez lens. All of the complexity is folded into the design and fabrication of the optical elements. As mentioned in the Alvarez patent [1] and elaborated upon in Palusinski et al.more » [2], if one is willing to fold even more complexity into the optical elements, it is possible to correct higher-order aberrations as well. There is no theoretical limit to the number or degree of wavefront distortions that can be corrected. The only limitation is that there must be a fixed relative magnitude of the aberrations. Independent correction of each component of the higher-order aberrations can not be performed without additional elements and degrees of freedom [3]. Under some circumstances, coupling may be observed between different aberrations. This can be mitigated with the appropriate choice of design parameters. New methods are available today that increase the practicality of making higher-order aberration correctors [4,5,6].« less

  17. Statistical estimation of ultrasonic propagation path parameters for aberration correction.

    PubMed

    Waag, Robert C; Astheimer, Jeffrey P

    2005-05-01

    Parameters in a linear filter model for ultrasonic propagation are found using statistical estimation. The model uses an inhomogeneous-medium Green's function that is decomposed into a homogeneous-transmission term and a path-dependent aberration term. Power and cross-power spectra of random-medium scattering are estimated over the frequency band of the transmit-receive system by using closely situated scattering volumes. The frequency-domain magnitude of the aberration is obtained from a normalization of the power spectrum. The corresponding phase is reconstructed from cross-power spectra of subaperture signals at adjacent receive positions by a recursion. The subapertures constrain the receive sensitivity pattern to eliminate measurement system phase contributions. The recursion uses a Laplacian-based algorithm to obtain phase from phase differences. Pulse-echo waveforms were acquired from a point reflector and a tissue-like scattering phantom through a tissue-mimicking aberration path from neighboring volumes having essentially the same aberration path. Propagation path aberration parameters calculated from the measurements of random scattering through the aberration phantom agree with corresponding parameters calculated for the same aberrator and array position by using echoes from the point reflector. The results indicate the approach describes, in addition to time shifts, waveform amplitude and shape changes produced by propagation through distributed aberration under realistic conditions.

  18. The neglected cranial nerve: nervus terminalis (cranial nerve N).

    PubMed

    Vilensky, Joel A

    2014-01-01

    The nervus terminalis (NT; terminal nerve) was clearly identified as an additional cranial nerve in humans more than a century ago yet remains mostly undescribed in modern anatomy textbooks. The nerve is referred to as the nervus terminalis because in species initially examined its fibers were seen entering the brain in the region of the lamina terminalis. It has also been referred to as cranial nerve 0, but because there is no Roman symbol for zero, an N for the Latin word nulla is a better numerical designation. This nerve is very distinct in human fetuses and infants but also has been repeatedly identified in adult human brains. The NT fibers are unmyelinated and emanate from ganglia. The fibers pass through the cribriform plate medial to those of the olfactory nerve fila. The fibers end in the nasal mucosa and probably arise from autonomic/neuromodulatory as well as sensory neurons. The NT has been demonstrated to release luteinizing-releasing luteinizing hormone and is therefore thought to play a role in reproductive behavior. Based on the available evidence, the NT appears to be functional in adult humans and should be taught in medical schools and incorporated into anatomy/neuroanatomy textbooks. Copyright © 2012 Wiley Periodicals, Inc., a Wiley company.

  19. Aberrant ocular architecture and function in patients with Klinefelter syndrome.

    PubMed

    Brand, Cristin; Zitzmann, Michael; Eter, Nicole; Kliesch, Sabine; Wistuba, Joachim; Alnawaiseh, Maged; Heiduschka, Peter

    2017-10-13

    Klinefelter Syndrome (KS), the most common chromosomal disorder in men (47,XXY), is associated with numerous comorbidities. Based on a number of isolated case reports, we performed the first systematic and comprehensive evaluation of eye health in KS patients with a focus on ocular structure and vascularization. Twenty-one KS patients and 26 male and 38 female controls underwent a variety of non-invasive examinations investigating ocular morphology (examination of retinal thickness, optic nerve head, and cornea) and function (visual field testing and quantification of ocular vessel density by optical coherence tomography angiography). In comparison to healthy controls, KS patients exhibited a smaller foveal avascular zone and a decreased retinal thickness due to a drastically thinner outer nuclear layer. The cornea of KS patients showed a decreased peripheral thickness and volume. In perimetry evaluation, KS patients required brighter stimuli and gave more irregular values. KS patients show an ocular phenotype including morphological and functional features, which is very likely caused by the supernumerary X chromosome. Thus, KS should not be limited to infertility, endocrine dysfunction, neurocognitive and psychosocial comorbidities. Defining an aberrant ocular morphology and function, awareness for possible eye problems should be raised.

  20. Facial reanimation by muscle-nerve neurotization after facial nerve sacrifice. Case report.

    PubMed

    Taupin, A; Labbé, D; Babin, E; Fromager, G

    2016-12-01

    Recovering a certain degree of mimicry after sacrifice of the facial nerve is a clinically recognized finding. The authors report a case of hemifacial reanimation suggesting a phenomenon of neurotization from muscle-to-nerve. A woman benefited from a parotidectomy with sacrifice of the left facial nerve indicated for recurrent tumor in the gland. The distal branches of the facial nerve, isolated at the time of resection, were buried in the masseter muscle underneath. The patient recovered a voluntary hémifacial motricity. The electromyographic analysis of the motor activity of the zygomaticus major before and after block of the masseter nerve showed a dependence between mimic muscles and the masseter muscle. Several hypotheses have been advanced to explain the spontaneous reanimation of facial paralysis. The clinical case makes it possible to argue in favor of muscle-to-nerve neurotization from masseter muscle to distal branches of the facial nerve. It illustrates the quality of motricity that can be obtained thanks to this procedure. The authors describe a simple implantation technique of distal branches of the facial nerve in the masseter muscle during a radical parotidectomy with facial nerve sacrifice and recovery of resting tone but also a quality voluntary mimicry. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  1. Engineering a multimodal nerve conduit for repair of injured peripheral nerve

    NASA Astrophysics Data System (ADS)

    Quigley, A. F.; Bulluss, K. J.; Kyratzis, I. L. B.; Gilmore, K.; Mysore, T.; Schirmer, K. S. U.; Kennedy, E. L.; O'Shea, M.; Truong, Y. B.; Edwards, S. L.; Peeters, G.; Herwig, P.; Razal, J. M.; Campbell, T. E.; Lowes, K. N.; Higgins, M. J.; Moulton, S. E.; Murphy, M. A.; Cook, M. J.; Clark, G. M.; Wallace, G. G.; Kapsa, R. M. I.

    2013-02-01

    Injury to nerve tissue in the peripheral nervous system (PNS) results in long-term impairment of limb function, dysaesthesia and pain, often with associated psychological effects. Whilst minor injuries can be left to regenerate without intervention and short gaps up to 2 cm can be sutured, larger or more severe injuries commonly require autogenous nerve grafts harvested from elsewhere in the body (usually sensory nerves). Functional recovery is often suboptimal and associated with loss of sensation from the tissue innervated by the harvested nerve. The challenges that persist with nerve repair have resulted in development of nerve guides or conduits from non-neural biological tissues and various polymers to improve the prognosis for the repair of damaged nerves in the PNS. This study describes the design and fabrication of a multimodal controlled pore size nerve regeneration conduit using polylactic acid (PLA) and (PLA):poly(lactic-co-glycolic) acid (PLGA) fibers within a neurotrophin-enriched alginate hydrogel. The nerve repair conduit design consists of two types of PLGA fibers selected specifically for promotion of axonal outgrowth and Schwann cell growth (75:25 for axons; 85:15 for Schwann cells). These aligned fibers are contained within the lumen of a knitted PLA sheath coated with electrospun PLA nanofibers to control pore size. The PLGA guidance fibers within the nerve repair conduit lumen are supported within an alginate hydrogel impregnated with neurotrophic factors (NT-3 or BDNF with LIF, SMDF and MGF-1) to provide neuroprotection, stimulation of axonal growth and Schwann cell migration. The conduit was used to promote repair of transected sciatic nerve in rats over a period of 4 weeks. Over this period, it was observed that over-grooming and self-mutilation (autotomy) of the limb implanted with the conduit was significantly reduced in rats implanted with the full-configuration conduit compared to rats implanted with conduits containing only an alginate

  2. Efficacy of low level laser therapy on neurosensory recovery after injury to the inferior alveolar nerve

    PubMed Central

    Ozen, Tuncer; Orhan, Kaan; Gorur, Ilker; Ozturk, Adnan

    2006-01-01

    Background The most severe complication after the removal of mandibular third molars is injury to the inferior alveolar nerve or the lingual nerve. These complications are rather uncommon (0.4% to 8.4%) and most of them are transient. However, some of them persist for longer than 6 months, which can leave various degrees of long-term permanent disability. While several methods such as pharmacologic therapy, microneurosurgery, autogenous and alloplastic grafting can be used for the treatment of long-standing sensory aberrations in the inferior alveolar nerve, there are few reports regarding low level laser treatment. This paper reports the effects of low level laser therapy in 4 patients with longstanding sensory nerve impairment following mandibular third molar surgery. Methods Four female patients had complaints of paresthesia and dysesthesia of the lip, chin and gingiva, and buccal regions. Each patient had undergone mandibular third molar surgery at least 1 year before. All patients were treated with low level laser therapy. Clinical neurosensory tests (the brush stroke directional discrimination test, 2-point discrimination test, and a subjective assessment of neurosensory function using a visual analog scale) were used before and after treatment, and the responses were plotted over time. Results When the neurosensory assessment scores after treatment with LLL therapy were compared with the baseline values prior to treatment, there was a significant acceleration in the time course, as well as in the magnitude, of neurosensory return. The VAS analysis revealed progressive improvement over time. Conclusion Low level laser therapy seemed to be conducive to the reduction of long-standing sensory nerve impairment following third molar surgery. Further studies are worthwhile regarding the clinical application of this treatment modality. PMID:16480503

  3. Influence of Misalignment on High-Order Aberration Correction for Normal Human Eyes

    NASA Astrophysics Data System (ADS)

    Zhao, Hao-Xin; Xu, Bing; Xue, Li-Xia; Dai, Yun; Liu, Qian; Rao, Xue-Jun

    2008-04-01

    Although a compensation device can correct aberrations of human eyes, the effect will be degraded by its misalignment, especially for high-order aberration correction. We calculate the positioning tolerance of correction device for high-order aberrations, and within what degree the correcting effect is better than low-order aberration (defocus and astigmatism) correction. With fixed certain misalignment within the positioning tolerance, we calculate the residual wavefront rms aberration of the first-6 to first-35 terms along with the 3rd-5th terms of aberrations corrected, and the combined first-13 terms of aberrations are also studied under the same quantity of misalignment. However, the correction effect of high-order aberrations does not meliorate along with the increase of the high-order terms under some misalignment, moreover, some simple combined terms correction can achieve similar result as complex combinations. These results suggest that it is unnecessary to correct too much the terms of high-order aberrations which are difficult to accomplish in practice, and gives confidence to correct high-order aberrations out of the laboratory.

  4. Synovial sarcoma of nerve.

    PubMed

    Scheithauer, Bernd W; Amrami, Kimberly K; Folpe, Andrew L; Silva, Ana I; Edgar, Mark A; Woodruff, James M; Levi, Allan D; Spinner, Robert J

    2011-04-01

    Tumors of peripheral nerve are largely neuroectodermal in nature and derived from 2 elements of nerve, Schwann or perineurial cells. In contrast, mesenchymal tumors affecting peripheral nerve are rare and are derived mainly from epineurial connective tissue. The spectrum of the latter is broad and includes lipoma, vascular neoplasms, hematopoietic tumors, and even meningioma. Of malignant peripheral nerve neoplasms, the vast majority are primary peripheral nerve sheath tumors. Malignancies of mesenchymal type are much less common. To date, only 12 cases of synovial sarcoma of nerve have been described. Whereas in the past, parallels were drawn between synovial sarcoma and malignant glandular schwannoma, an uncommon form of malignant peripheral nerve sheath tumor, molecular genetics have since clarified the distinction. Herein, we report 10 additional examples of molecularly confirmed synovial sarcoma, all arising within minor or major nerves. Affecting 7 female and 3 male patients, 4 tumors occurred in pediatric patients. Clinically and radiologically, most lesions were initially thought to be benign nerve sheath tumors. On reinterpretation of imaging, they were considered indeterminate in nature with some features suspicious for malignancy. Synovial sarcoma of nerve, albeit rare, seems to behave in a manner similar to its more common, soft tissue counterpart. Those affecting nerve have a variable prognosis. Definitive recommendations regarding surgery and adjuvant therapies await additional reports and long-term follow-up. The literature is reviewed and a meta-analysis is performed with respect to clinicopathologic features versus outcome. Copyright © 2011. Published by Elsevier Inc.

  5. Orthonormal aberration polynomials for anamorphic optical imaging systems with rectangular pupils.

    PubMed

    Mahajan, Virendra N

    2010-12-20

    The classical aberrations of an anamorphic optical imaging system, representing the terms of a power-series expansion of its aberration function, are separable in the Cartesian coordinates of a point on its pupil. We discuss the balancing of a classical aberration of a certain order with one or more such aberrations of lower order to minimize its variance across a rectangular pupil of such a system. We show that the balanced aberrations are the products of two Legendre polynomials, one for each of the two Cartesian coordinates of the pupil point. The compound Legendre polynomials are orthogonal across a rectangular pupil and, like the classical aberrations, are inherently separable in the Cartesian coordinates of the pupil point. They are different from the balanced aberrations and the corresponding orthogonal polynomials for a system with rotational symmetry but a rectangular pupil.

  6. Lateral rectus myositis mimicking an abducens nerve palsy in a pregnant woman.

    PubMed

    Haslinda, Abd-Rahim; Shatriah, Ismail; Azhany, Yaakub; Nik-Ahmad-Zuky, Nik-Lah; Yunus, Rohaizan

    2014-01-01

    Myositis is a rare unknown inflammatory disorder of the skeletal muscle tissue. Generalized inflammatory myopathies, polymyositis, and dermatomyositis have been reported during pregnancy. Isolated orbital myositis in pregnancy has not been previously described in the literature. The authors report a case of left isolated orbital myositis in a primigravida at 38 weeks gestation affecting the patient's left lateral rectus muscle. MRI of the orbit was consistent with the diagnosis. She showed remarkable clinical improvement with oral corticosteroids therapy.

  7. [Which changes occur in nerve grafts harvested with a nerve stripper? Morphological studies].

    PubMed

    Koller, R; Frey, M; Rab, M; Deutinger, M; Freilinger, G

    1995-03-01

    A histological and morphometric study was undertaken in order to evaluate the alterations in sural nerves harvested for nerve grafting using a nerve stripper. In 19 nerves biopsies were taken from the proximal and/or the distal end of the stripped nerve graft. Cross sections were examined for alterations of the perineurium and the myelin sheaths. In four nerves alterations within the perineurium were found, which affected 37% of the endoneural cross-sectional area on the average. In all specimens, the perineurial sheath was seen to be intact. The results of the present study suggest that harvesting of a nerve graft using a stripper does not cause major injuries to the graft and therefore successful neurotization of the graft should not be impaired.

  8. Peripheral Nerve Regeneration Strategies: Electrically Stimulating Polymer Based Nerve Growth Conduits

    PubMed Central

    Anderson, Matthew; Shelke, Namdev B.; Manoukian, Ohan S.; Yu, Xiaojun; McCullough, Louise D.; Kumbar, Sangamesh G.

    2017-01-01

    Treatment of large peripheral nerve damages ranges from the use of an autologous nerve graft to a synthetic nerve growth conduit. Biological grafts, in spite of many merits, show several limitations in terms of availability and donor site morbidity, and outcomes are suboptimal due to fascicle mismatch, scarring, and fibrosis. Tissue engineered nerve graft substitutes utilize polymeric conduits in conjunction with cues both chemical and physical, cells alone and or in combination. The chemical and physical cues delivered through polymeric conduits play an important role and drive tissue regeneration. Electrical stimulation (ES) has been applied toward the repair and regeneration of various tissues such as muscle, tendon, nerve, and articular tissue both in laboratory and clinical settings. The underlying mechanisms that regulate cellular activities such as cell adhesion, proliferation, cell migration, protein production, and tissue regeneration following ES is not fully understood. Polymeric constructs that can carry the electrical stimulation along the length of the scaffold have been developed and characterized for possible nerve regeneration applications. We discuss the use of electrically conductive polymers and associated cell interaction, biocompatibility, tissue regeneration, and recent basic research for nerve regeneration. In conclusion, a multifunctional combinatorial device comprised of biomaterial, structural, functional, cellular, and molecular aspects may be the best way forward for effective peripheral nerve regeneration. PMID:27278739

  9. Chitosan-film enhanced chitosan nerve guides for long-distance regeneration of peripheral nerves.

    PubMed

    Meyer, Cora; Stenberg, Lena; Gonzalez-Perez, Francisco; Wrobel, Sandra; Ronchi, Giulia; Udina, Esther; Suganuma, Seigo; Geuna, Stefano; Navarro, Xavier; Dahlin, Lars B; Grothe, Claudia; Haastert-Talini, Kirsten

    2016-01-01

    Biosynthetic nerve grafts are developed in order to complement or replace autologous nerve grafts for peripheral nerve reconstruction. Artificial nerve guides currently approved for clinical use are not widely applied in reconstructive surgery as they still have limitations especially when it comes to critical distance repair. Here we report a comprehensive analysis of fine-tuned chitosan nerve guides (CNGs) enhanced by introduction of a longitudinal chitosan film to reconstruct critical length 15 mm sciatic nerve defects in adult healthy Wistar or diabetic Goto-Kakizaki rats. Short and long term investigations demonstrated that the CNGs enhanced by the guiding structure of the introduced chitosan film significantly improved functional and morphological results of nerve regeneration in comparison to simple hollow CNGs. Importantly, this was detectable both in healthy and in diabetic rats (short term) and the regeneration outcome almost reached the outcome after autologous nerve grafting (long term). Hollow CNGs provide properties likely leading to a wider clinical acceptance than other artificial nerve guides and their performance can be increased by simple introduction of a chitosan film with the same advantageous properties. Therefore, the chitosan film enhanced CNGs represent a new generation medical device for peripheral nerve reconstruction. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  10. Enhanced peripheral nerve regeneration through asymmetrically porous nerve guide conduit with nerve growth factor gradient.

    PubMed

    Oh, Se Heang; Kang, Jun Goo; Kim, Tae Ho; Namgung, Uk; Song, Kyu Sang; Jeon, Byeong Hwa; Lee, Jin Ho

    2018-01-01

    In this study, we fabricated a nerve guide conduit (NGC) with nerve growth factor (NGF) gradient along the longitudinal direction by rolling a porous polycaprolactone membrane with NGF concentration gradient. The NGF immobilized on the membrane was continuously released for up to 35 days, and the released amount of the NGF from the membrane gradually increased from the proximal to distal NGF ends, which may allow a neurotrophic factor gradient in the tubular NGC for a sufficient period. From the in vitro cell culture experiment, it was observed that the PC12 cells sense the NGF concentration gradient on the membrane for the cell proliferation and differentiation. From the in vivo animal experiment using a long gap (20 mm) sciatic nerve defect model of rats, the NGC with NGF concentration gradient allowed more rapid nerve regeneration through the NGC than the NGC itself and NGC immobilized with uniformly distributed NGF. The NGC with NGF concentration gradient seems to be a promising strategy for the peripheral nerve regeneration. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 52-64, 2018. © 2017 Wiley Periodicals, Inc.

  11. Treatment of peroneal nerve injuries with simultaneous tendon transfer and nerve exploration.

    PubMed

    Ho, Bryant; Khan, Zubair; Switaj, Paul J; Ochenjele, George; Fuchs, Daniel; Dahl, William; Cederna, Paul; Kung, Theodore A; Kadakia, Anish R

    2014-08-06

    Common peroneal nerve palsy leading to foot drop is difficult to manage and has historically been treated with extended bracing with expectant waiting for return of nerve function. Peroneal nerve exploration has traditionally been avoided except in cases of known traumatic or iatrogenic injury, with tendon transfers being performed in a delayed fashion after exhausting conservative treatment. We present a new strategy for management of foot drop with nerve exploration and concomitant tendon transfer. We retrospectively reviewed a series of 12 patients with peroneal nerve palsies that were treated with tendon transfer from 2005 to 2011. Of these patients, seven were treated with simultaneous peroneal nerve exploration and repair at the time of tendon transfer. Patients with both nerve repair and tendon transfer had superior functional results with active dorsiflexion in all patients, compared to dorsiflexion in 40% of patients treated with tendon transfers alone. Additionally, 57% of patients treated with nerve repair and tendon transfer were able to achieve enough function to return to running, compared to 20% in patients with tendon transfer alone. No patient had full return of native motor function resulting in excessive dorsiflexion strength. The results of our limited case series for this rare condition indicate that simultaneous nerve repair and tendon transfer showed no detrimental results and may provide improved function over tendon transfer alone.

  12. Reinnervation of Urethral and Anal Sphincters With Femoral Motor Nerve to Pudendal Nerve Transfer

    PubMed Central

    Ruggieri, Michael R.; Braverman, Alan S.; Bernal, Raymond M.; Lamarre, Neil S.; Brown, Justin M.; Barbe, Mary F.

    2012-01-01

    Aims Lower motor neuron damage to sacral roots or nerves can result in incontinence and a flaccid urinary bladder. We showed bladder reinnervation after transfer of coccygeal to sacral ventral roots, and genitofemoral nerves (L1, 2 origin) to pelvic nerves. This study assesses the feasibility of urethral and anal sphincter reinnervation using transfer of motor branches of the femoral nerve (L2–4 origin) to pudendal nerves (S1, 2 origin) that innervate the urethral and anal sphincters in a canine model. Methods Sacral ventral roots were selected by their ability to stimulate bladder, urethral sphincter, and anal sphincter contraction and transected. Bilaterally, branches of the femoral nerve, specifically, nervus saphenous pars muscularis [Evans HE. Miller’s anatomy of the dog. Philadelphia: W.B. Saunders; 1993], were transferred and end-to-end anastomosed to transected pudendal nerve branches in the perineum, then enclosed in unipolar nerve cuff electrodes with leads to implanted RF micro-stimulators. Results Nerve stimulation induced increased anal and urethral sphincter pressures in five of six transferred nerves. Retrograde neurotracing from the bladder, urethral sphincter, and anal sphincter using fluorogold, fast blue, and fluororuby, demonstrated urethral and anal sphincter labeled neurons in L2–4 cord segments (but not S1–3) in nerve transfer canines, consistent with rein-nervation by the transferred femoral nerve motor branches. Controls had labeled neurons only in S1–3 segments. Postmortem DiI and DiO labeling confirmed axonal regrowth across the nerve repair site. Conclusions These results show spinal cord reinnervation of urethral and anal sphincter targets after sacral ventral root transection and femoral nerve transfer (NT) to the denervated pudendal nerve. These surgical procedures may allow patients to regain continence. PMID:21953679

  13. Laparoscopic anatomy of the autonomic nerves of the pelvis and the concept of nerve-sparing surgery by direct visualization of autonomic nerve bundles.

    PubMed

    Lemos, Nucelio; Souza, Caroline; Marques, Renato Moretti; Kamergorodsky, Gil; Schor, Eduardo; Girão, Manoel J B C

    2015-11-01

    To demonstrate the laparoscopic neuroanatomy of the autonomic nerves of the pelvis using the laparoscopic neuronavigation technique, as well as the technique for a nerve-sparing radical endometriosis surgery. Step-by-step explanation of the technique using videos and pictures (educational video) to demonstrate the anatomy of the intrapelvic bundles of the autonomic nerve system innervating the bladder, rectum, and pelvic floor. Tertiary referral center. One 37-year-old woman with an infiltrative endometriotic nodule on the anterior third of the left uterosacral ligament and one 34-year-old woman with rectovaginal endometriosis. Exposure and preservation by direct visualization of the hypogastric nerve and the inferior hypogastric plexus. Visual control and identification of the autonomic nerve branches of the posterior pelvis. Exposure and preservation of the hypogastric nerve and the superficial part of the left hypogastric nerve were achieved on the first patient. Nerve roots S2, S3, and S4 were identified on the second patient, allowing for the exposure and preservation of the pelvic splanchnic nerves and the deep portion inferior hypogastric plexus. Radical surgery for endometriosis can induce urinary dysfunction in 2.4%-17.5% of patients owing to lesion of the autonomic nerves. The surgeon's knowledge of the anatomy of these nerves is the main factor for preserving postoperative urinary function. The following nerves are the intrapelvic part of the autonomic nervous system: the hypogastric nerves, which derive from the superior hypogastric plexus and carry the sympathetic signals to the internal urethral and anal sphincters as well as to the pelvic visceral proprioception; and the pelvic splanchnic nerves, which arise from S2 to S4 and carry nociceptive and parasympathetic signals to the bladder, rectum, and the sigmoid and left colons. The hypogastric and pelvic splanchnic nerves merge into the pararectal fossae to form the inferior hypogastric plexus. Most

  14. Theory of aberration fields for general optical systems with freeform surfaces.

    PubMed

    Fuerschbach, Kyle; Rolland, Jannick P; Thompson, Kevin P

    2014-11-03

    This paper utilizes the framework of nodal aberration theory to describe the aberration field behavior that emerges in optical systems with freeform optical surfaces, particularly φ-polynomial surfaces, including Zernike polynomial surfaces, that lie anywhere in the optical system. If the freeform surface is located at the stop or pupil, the net aberration contribution of the freeform surface is field constant. As the freeform optical surface is displaced longitudinally away from the stop or pupil of the optical system, the net aberration contribution becomes field dependent. It is demonstrated that there are no new aberration types when describing the aberration fields that arise with the introduction of freeform optical surfaces. Significantly it is shown that the aberration fields that emerge with the inclusion of freeform surfaces in an optical system are exactly those that have been described by nodal aberration theory for tilted and decentered optical systems. The key contribution here lies in establishing the field dependence and nodal behavior of each freeform term that is essential knowledge for effective application to optical system design. With this development, the nodes that are distributed throughout the field of view for each aberration type can be anticipated and targeted during optimization for the correction or control of the aberrations in an optical system with freeform surfaces. This work does not place any symmetry constraints on the optical system, which could be packaged in a fully three dimensional geometry, without fold mirrors.

  15. Electrophysiology of Cranial Nerve Testing: Cranial Nerves IX and X.

    PubMed

    Martinez, Alberto R M; Martins, Melina P; Moreira, Ana Lucila; Martins, Carlos R; Kimaid, Paulo A T; França, Marcondes C

    2018-01-01

    The cranial nerves IX and X emerge from medulla oblongata and have motor, sensory, and parasympathetic functions. Some of these are amenable to neurophysiological assessment. It is often hard to separate the individual contribution of each nerve; in fact, some of the techniques are indeed a composite functional measure of both nerves. The main methods are the evaluation of the swallowing function (combined IX and X), laryngeal electromyogram (predominant motor vagal function), and heart rate variability (predominant parasympathetic vagal function). This review describes, therefore, the techniques that best evaluate the major symptoms presented in IX and X cranial nerve disturbance: dysphagia, dysphonia, and autonomic parasympathetic dysfunction.

  16. Phrenic nerve transfer to the musculocutaneous nerve for the repair of brachial plexus injury: electrophysiological characteristics

    PubMed Central

    Liu, Ying; Xu, Xun-cheng; Zou, Yi; Li, Su-rong; Zhang, Bin; Wang, Yue

    2015-01-01

    Phrenic nerve transfer is a major dynamic treatment used to repair brachial plexus root avulsion. We analyzed 72 relevant articles on phrenic nerve transfer to repair injured brachial plexus that were indexed by Science Citation Index. The keywords searched were brachial plexus injury, phrenic nerve, repair, surgery, protection, nerve transfer, and nerve graft. In addition, we performed neurophysiological analysis of the preoperative condition and prognosis of 10 patients undergoing ipsilateral phrenic nerve transfer to the musculocutaneous nerve in our hospital from 2008 to 201 3 and observed the electromyograms of the biceps brachii and motor conduction function of the musculocutaneous nerve. Clinically, approximately 28% of patients had brachial plexus injury combined with phrenic nerve injury, and injured phrenic nerve cannot be used as a nerve graft. After phrenic nerve transfer to the musculocutaneous nerve, the regenerated potentials first appeared at 3 months. Recovery of motor unit action potential occurred 6 months later and became more apparent at 12 months. The percent of patients recovering ‘excellent’ and ‘good’ muscle strength in the biceps brachii was 80% after 18 months. At 12 months after surgery, motor nerve conduction potential appeared in the musculocutaneous nerve in seven cases. These data suggest that preoperative evaluation of phrenic nerve function may help identify the most appropriate nerve graft in patients with an injured brachial plexus. The functional recovery of a transplanted nerve can be dynamically observed after the surgery. PMID:25883637

  17. Phrenic nerve transfer to the musculocutaneous nerve for the repair of brachial plexus injury: electrophysiological characteristics.

    PubMed

    Liu, Ying; Xu, Xun-Cheng; Zou, Yi; Li, Su-Rong; Zhang, Bin; Wang, Yue

    2015-02-01

    Phrenic nerve transfer is a major dynamic treatment used to repair brachial plexus root avulsion. We analyzed 72 relevant articles on phrenic nerve transfer to repair injured brachial plexus that were indexed by Science Citation Index. The keywords searched were brachial plexus injury, phrenic nerve, repair, surgery, protection, nerve transfer, and nerve graft. In addition, we performed neurophysiological analysis of the preoperative condition and prognosis of 10 patients undergoing ipsilateral phrenic nerve transfer to the musculocutaneous nerve in our hospital from 2008 to 201 3 and observed the electromyograms of the biceps brachii and motor conduction function of the musculocutaneous nerve. Clinically, approximately 28% of patients had brachial plexus injury combined with phrenic nerve injury, and injured phrenic nerve cannot be used as a nerve graft. After phrenic nerve transfer to the musculocutaneous nerve, the regenerated potentials first appeared at 3 months. Recovery of motor unit action potential occurred 6 months later and became more apparent at 12 months. The percent of patients recovering 'excellent' and 'good' muscle strength in the biceps brachii was 80% after 18 months. At 12 months after surgery, motor nerve conduction potential appeared in the musculocutaneous nerve in seven cases. These data suggest that preoperative evaluation of phrenic nerve function may help identify the most appropriate nerve graft in patients with an injured brachial plexus. The functional recovery of a transplanted nerve can be dynamically observed after the surgery.

  18. Development of a nerve conduction technique for the recurrent laryngeal nerve.

    PubMed

    J Kim, Sang; G Lee, Dae; Kwon, Jeong-Yi

    2014-12-01

    To develop a reliable and safe laryngeal nerve conduction technique and to obtain consistent parameters as normal reference values. A prospective single-arm study. A nerve conduction test was performed on the contralateral normal side in 42 patients with unilateral vocal fold palsy. The recording was performed in the intact thyroarytenoid muscle using a monopolar needle. The electrical stimulation using a 37-mm monopolar needle was applied 3 cm below the lower margin of the cricoid cartilage, just lateral to the trachea and medial to the carotid artery, and its intensity was gradually increased until the amplitude of the electrical response reached the maximum level. The latency of the evoked muscle response was acquired at the first evoked waveform deflection from the baseline. The average latency of the recurrent laryngeal nerves was 1.98 ± 0.26 ms. The latencies showed normal distribution according to the quantile-quantile plot and Kolmogorov-Smirnov test (P = .098). There was no significant difference in latencies between the right and left recurrent laryngeal nerves. Anthropometric factors including height and weight did not show any correlation with the latencies. We developed a reliable and safe laryngeal nerve conduction technique and obtained normal reference values for the recurrent laryngeal nerve conduction study. This laryngeal nerve conduction study can be an additional tool for detecting recurrent laryngeal nerve injury if it is performed in combination with the conventional laryngeal electromyography. 4. © 2014 The American Laryngological, Rhinological and Otological Society, Inc.

  19. Image based method for aberration measurement of lithographic tools

    NASA Astrophysics Data System (ADS)

    Xu, Shuang; Tao, Bo; Guo, Yongxing; Li, Gongfa

    2018-01-01

    Information of lens aberration of lithographic tools is important as it directly affects the intensity distribution in the image plane. Zernike polynomials are commonly used for a mathematical description of lens aberrations. Due to the advantage of lower cost and easier implementation of tools, image based measurement techniques have been widely used. Lithographic tools are typically partially coherent systems that can be described by a bilinear model, which entails time consuming calculations and does not lend a simple and intuitive relationship between lens aberrations and the resulted images. Previous methods for retrieving lens aberrations in such partially coherent systems involve through-focus image measurements and time-consuming iterative algorithms. In this work, we propose a method for aberration measurement in lithographic tools, which only requires measuring two images of intensity distribution. Two linear formulations are derived in matrix forms that directly relate the measured images to the unknown Zernike coefficients. Consequently, an efficient non-iterative solution is obtained.

  20. Minimum change in spherical aberration that can be perceived

    PubMed Central

    Manzanera, Silvestre; Artal, Pablo

    2016-01-01

    It is important to know the visual sensitivity to optical blur from both a basic science perspective and a practical point of view. Of particular interest is the sensitivity to blur induced by spherical aberration because it is being used to increase depth of focus as a component of a presbyopic solution. Using a flicker detection-based procedure implemented on an adaptive optics visual simulator, we measured the spherical aberration thresholds that produce just-noticeable differences in perceived image quality. The thresholds were measured for positive and negative values of spherical aberration, for best focus and + 0.5 D and + 1.0 D of defocus. At best focus, the SA thresholds were 0.20 ± 0.01 µm and −0.17 ± 0.03 µm for positive and negative spherical aberration respectively (referred to a 6-mm pupil). These experimental values may be useful in setting spherical aberration permissible levels in different ophthalmic techniques. PMID:27699113

  1. Surface geometry and optical aberrations of ex-vivo crystalline lenses

    NASA Astrophysics Data System (ADS)

    Bueno, Juan M.; Schwarz, Christina; Acosta, Eva; Artal, Pablo

    2010-02-01

    The shape of the surfaces of ex-vivo human crystalline lenses was measured using a shadow photography technique. From these data, the back-focal distance and the contribution of each surface to the main optical aberrations of the lenses were estimated. The aberrations of the lenses were measured separately with two complementary techniques: a Hartmann-Shack wavefront sensor and a point-diffraction interferometer. A laser scanning set-up was also used to measure the actual back-focal length as well as the phase aberration in one meridian section of the lenses. Measured and predicted back-focal length agreed well within the experimental errors. The lens aberrations computed with a ray-tracing approach from the measured surfaces and geometrical data only reproduce quantitatively the measured aberrations.

  2. An update-tissue engineered nerve grafts for the repair of peripheral nerve injuries.

    PubMed

    Patel, Nitesh P; Lyon, Kristopher A; Huang, Jason H

    2018-05-01

    Peripheral nerve injuries (PNI) are caused by a range of etiologies and result in a broad spectrum of disability. While nerve autografts are the current gold standard for the reconstruction of extensive nerve damage, the limited supply of autologous nerve and complications associated with harvesting nerve from a second surgical site has driven groups from multiple disciplines, including biomedical engineering, neurosurgery, plastic surgery, and orthopedic surgery, to develop a suitable or superior alternative to autografting. Over the last couple of decades, various types of scaffolds, such as acellular nerve grafts (ANGs), nerve guidance conduits, and non-nervous tissues, have been filled with Schwann cells, stem cells, and/or neurotrophic factors to develop tissue engineered nerve grafts (TENGs). Although these have shown promising effects on peripheral nerve regeneration in experimental models, the autograft has remained the gold standard for large nerve gaps. This review provides a discussion of recent advances in the development of TENGs and their efficacy in experimental models. Specifically, TENGs have been enhanced via incorporation of genetically engineered cells, methods to improve stem cell survival and differentiation, optimized delivery of neurotrophic factors via drug delivery systems (DDS), co-administration of platelet-rich plasma (PRP), and pretreatment with chondroitinase ABC (Ch-ABC). Other notable advancements include conduits that have been bioengineered to mimic native nerve structure via cell-derived extracellular matrix (ECM) deposition, and the development of transplantable living nervous tissue constructs from rat and human dorsal root ganglia (DRG) neurons. Grafts composed of non-nervous tissues, such as vein, artery, and muscle, will be briefly discussed.

  3. Silk fibroin enhances peripheral nerve regeneration by improving vascularization within nerve conduits.

    PubMed

    Wang, Chunyang; Jia, Yachao; Yang, Weichao; Zhang, Cheng; Zhang, Kuihua; Chai, Yimin

    2018-07-01

    Silk fibroin (SF)-based nerve conduits have been widely used to bridge peripheral nerve defects. Our previous study showed that nerve regeneration in a SF-blended poly (l-lactide-co-ɛ-caprolactone) [P(LLA-CL)] nerve conduit is better than that in a P(LLA-CL) conduit. However, the involved mechanisms remain unclarified. Because angiogenesis within a nerve conduit plays an important role in nerve regeneration, vascularization of SF/P(LLA-CL) and P(LLA-CL) conduits was compared both in vitro and in vivo. In the present study, we observed that SF/P(LLA-CL) nanofibers significantly promoted fibroblast proliferation, and vascular endothelial growth factor secreted by fibroblasts seeded in SF/P(LLA-CL) nanofibers was more than seven-fold higher than that in P(LLA-CL) nanofibers. Conditioned medium of fibroblasts in the SF/P(LLA-CL) group stimulated more human umbilical vein endothelial cells (HUVEC) to form capillary-like networks and promoted faster HUVEC migration. The two kinds of nerve conduits were used to bridge 10-mm-length nerve defects in rats. At 3 weeks of reparation, the blood vessel area in the SF/P(LLA-CL) group was significantly larger than that in the P(LLA-CL) group. More regenerated axons and Schwann cells were also observed in the SF/P(LLA-CL) group, which was consistent with the results of blood vessels. Collectively, our data revealed that the SF/P(LLA-CL) nerve conduit enhances peripheral nerve regeneration by improving angiogenesis within the conduit. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 2070-2077, 2018. © 2018 Wiley Periodicals, Inc.

  4. Pre-differentiation of mesenchymal stromal cells in combination with a microstructured nerve guide supports peripheral nerve regeneration in the rat sciatic nerve model.

    PubMed

    Boecker, Arne Hendrik; van Neerven, Sabien Geraldine Antonia; Scheffel, Juliane; Tank, Julian; Altinova, Haktan; Seidensticker, Katrin; Deumens, Ronald; Tolba, Rene; Weis, Joachim; Brook, Gary Anthony; Pallua, Norbert; Bozkurt, Ahmet

    2016-02-01

    Many bioartificial nerve guides have been investigated pre-clinically for their nerve regeneration-supporting function, often in comparison to autologous nerve transplantation, which is still regarded as the current clinical gold standard. Enrichment of these scaffolds with cells intended to support axonal regeneration has been explored as a strategy to boost axonal regeneration across these nerve guides Ansselin et al. (1998). In the present study, 20 mm rat sciatic nerve defects were implanted with a cell-seeded microstructured collagen nerve guide (Perimaix) or an autologous nerve graft. Under the influence of seeded, pre-differentiated mesenchymal stromal cells, axons regenerated well into the Perimaix nerve guide. Myelination-related parameters, like myelin sheath thickness, benefitted from an additional seeding with pre-differentiated mesenchymal stromal cells. Furthermore, both the number of retrogradely labelled sensory neurons and the axon density within the implant were elevated in the cell-seeded scaffold group with pre-differentiated mesenchymal stromal cells. However, a pre-differentiation had no influence on functional recovery. An additional cell seeding of the Perimaix nerve guide with mesenchymal stromal cells led to an extent of functional recovery, independent of the differentiation status, similar to autologous nerve transplantation. These findings encourage further investigations on pre-differentiated mesenchymal stromal cells as a cellular support for peripheral nerve regeneration. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  5. Extralaryngeal division of the recurrent laryngeal nerve: a new description for the inferior laryngeal nerve.

    PubMed

    Yalcin, Bulent; Tunali, Selcuk; Ozan, Hasan

    2008-05-01

    Extralaryngeal division of the recurrent laryngeal nerve was contradictory in the literature. We aimed to investigate extralaryngeal division of the nerve, and also propose a new description for the inferior laryngeal nerve. Sixty specimens (120 sides) were examined for this project, including 41 men and 19 women cadavers between the ages of 40 and 89 years at death. In one right side, terminal segment of the nerve gave off many small branches surrounding the inferior thyroid artery then reaching the larynx, trachea, thyroid gland and esophagus. In eight sides, terminal segment of the nerve had no extralaryngeal division and entered the larynx as a single trunk. In 110 sides, the nerve had extralaryngeal division. One hundred and three nerves had two laryngeal and one to three extralaryngeal branches. Two types were described in this group. In type I (66 nerves), both branches arose from the same level of nerve. Type I had two subtypes: type Ia, the origin of the branches was just below the inferior constrictor muscle; type Ib, the origin of the branches was 15-35 mm below the muscle. In type II (37 nerves), the laryngeal branches arose just 3-5 mm above the extralaryngeal branches. We observed that the laryngeal and extralaryngeal branches arose generally from the same point of the recurrent laryngeal nerve. The inferior laryngeal nerve is thus very short, or even nonexistent. Therefore, we suggest that if the term "superior laryngeal nerve" is a given, standard, and accepted term, then the term "inferior laryngeal nerve" should also be accepted instead of the term "recurrent laryngeal nerve."

  6. Genotoxicity of mercury used in chromosome aberration tests.

    PubMed

    Akiyama, M; Oshima, H; Nakamura, M

    2001-01-01

    The purpose of this study was to investigate the genotoxic effects of Hg released from dental amalgams. The chromosome aberration test was conducted using original extracts and their diluted solutions of conventional type amalgam and high copper amalgam. The concentrations of Hg, Cu and Ag in the original extract of high copper amalgam were 17.64, 7.97 and 43.90 microM, respectively. Those in the original extract of conventional type amalgam were 20.63, 7.87 and 14.79 microM, respectively. 10 and 30 microM Hg(2+) were also used for comparison. The frequency of chromosome aberrations was below 5% with 0 microM Hg(2+) and with a triple dilution of high copper amalgam extract, containing 5.88 microM Hg, 14.63 microM Cu and 2.65 microM Ag. However, 9.5% of the cells showed chromosome aberrations with a quadruple dilution of conventional type amalgam, containing 5.15 microM Hg, 3.69 microM Cu and 1.96 microM Ag. The amount of Hg in the quadruple dilution of conventional type amalgam was less than that in the triple dilution of high copper amalgam extract and 10 microM Hg(2+). A concentration of 30 microM Hg(2+) caused 34.5% of the cells to show chromosome aberrations while with a two-thirds dilution of high copper amalgam extract, containing 11.76 microM Hg, 29.26 microM Cu and 5.31 microM Ag, 58.5% of the cells showed chromosome aberrations. A two-thirds dilution of high copper amalgam extract induced more chromosome aberrations than 30 microM Hg(2+), although the amount of Hg was less than 30 microM Hg(2+). A triple dilution of conventional type amalgam extract, original extracts of conventional type amalgam and high copper amalgam and 100 microM Hg(2+) were induced few metaphases. It was revealed that the conventional type amalgam induced chromosome aberrations with quadruple dilution where cell viability was about 80% and that the high copper amalgam induced a high level of chromosome aberrations with the two-thirds dilution. The effects of low level Hg on humans

  7. Intraoperative cranial nerve monitoring.

    PubMed

    Harper, C Michel

    2004-03-01

    The purpose of intraoperative monitoring is to preserve function and prevent injury to the nervous system at a time when clinical examination is not possible. Cranial nerves are delicate structures and are susceptible to damage by mechanical trauma or ischemia during intracranial and extracranial surgery. A number of reliable electrodiagnostic techniques, including nerve conduction studies, electromyography, and the recording of evoked potentials have been adapted to the study of cranial nerve function during surgery. A growing body of evidence supports the utility of intraoperative monitoring of cranial nerve nerves during selected surgical procedures.

  8. Tendon Transfers Part II: Transfers for Ulnar Nerve Palsy and Median Nerve Palsy

    PubMed Central

    Sammer, Douglas M.; Chung, Kevin C.

    2009-01-01

    Objectives After reading this article (part II of II), the participant should be able to: 1. Describe the anatomy and function of the median and ulnar nerves in the forearm and hand. 2. Describe the clinical deficits associated with injury to each nerve. 3. Describe the indications, benefits, and drawbacks for various tendon transfer procedures used to treat median and ulnar nerve palsy.4. Describe the treatment of combined nerve injuries. 5. Describe postoperative care and possible complications associated with these tendon transfer procedures. Summary This article discusses the use of tendon transfer procedures for treatment of median and ulnar nerve palsy as well as combined nerve palsies. Postoperative management and potential complications are also discussed. PMID:19730287

  9. Microsurgical reconstruction of large nerve defects using autologous nerve grafts.

    PubMed

    Daoutis, N K; Gerostathopoulos, N E; Efstathopoulos, D G; Misitizis, D P; Bouchlis, G N; Anagnostou, S K

    1994-01-01

    Between 1986 and 1993, 643 patients with peripheral nerve trauma were treated in our clinic. Primary neurorraphy was performed in 431 of these patients and nerve grafting in 212 patients. We present the functional results after nerve grafting in 93 patients with large nerve defects who were followed for more than 2 years. Evaluation of function was based on the Medical Research Council (MRC) classification for motor and sensory recovery. Factors affecting functional outcome, such as age of the patient, denervation time, length of the defect, and level of the injury were noted. Good results according to the MRC classification were obtained in the majority of cases, although function remained less than that of the uninjured side.

  10. Use of Nerve Conduction Velocity to Assess Peripheral Nerve Health in Aging Mice

    PubMed Central

    Walsh, Michael E.; Sloane, Lauren B.; Fischer, Kathleen E.; Austad, Steven N.; Richardson, Arlan

    2015-01-01

    Nerve conduction velocity (NCV), the speed at which electrical signals propagate along peripheral nerves, is used in the clinic to evaluate nerve function in humans. A decline in peripheral nerve function is associated with a number of age-related pathologies. While several studies have shown that NCV declines with age in humans, there is little information on the effect of age on NCV in peripheral nerves in mice. In this study, we evaluated NCV in male and female C57Bl/6 mice ranging from 4 to 32 months of age. We observed a decline in NCV in both male and female mice after 20 months of age. Sex differences were detected in sensory NCV as well as the rate of decline during aging in motor nerves; female mice had slower sensory NCV and a slower age-related decline in motor nerves compared with male mice. We also tested the effect of dietary restriction on NCV in 30-month-old female mice. Dietary restriction prevented the age-related decline in sciatic NCV but not other nerves. Because NCV is clinically relevant to the assessment of nerve function, we recommend that NCV be used to evaluate healthspan in assessing genetic and pharmacological interventions that increase the life span of mice. PMID:25477428

  11. A silk sericin/silicone nerve guidance conduit promotes regeneration of a transected sciatic nerve.

    PubMed

    Xie, Hongjian; Yang, Wen; Chen, Jianghai; Zhang, Jinxiang; Lu, Xiaochen; Zhao, Xiaobo; Huang, Kun; Li, Huili; Chang, Panpan; Wang, Zheng; Wang, Lin

    2015-10-28

    Peripheral nerve gap defects lead to significant loss of sensory or motor function. Tissue engineering has become an important alternative to nerve repair. Sericin, a major component of silk, is a natural protein whose value in tissue engineering has just begun to be explored. Here, the first time use of sericin in vivo is reported as a long-term implant for peripheral nerve regeneration. A sericin nerve guidance conduit is designed and fabricated. This conduit is highly porous with mechanical strength matching peripheral nerve tissue. It supports Schwann cell proliferation and is capable of up-regulating the transcription of glial cell derived neurotrophic factor and nerve growth factor in Schwann cells. The sericin conduit wrapped with a silicone conduit (sericin/silicone double conduits) is used for bridging repair of a 5 mm gap in a rat sciatic nerve transection model. The sericin/silicone double conduits achieve functional recovery comparable to that of autologous nerve grafting as evidenced by drastically improved nerve function and morphology. Importantly, this improvement is mainly attributed to the sericin conduit as the silicone conduit alone only produces marginal functional recovery. This sericin/silicone-double-conduit strategy offers an efficient and valuable alternative to autologous nerve grafting for repairing damaged peripheral nerve. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Transfer of obturator nerve for femoral nerve injury: an experiment study in rats.

    PubMed

    Meng, Depeng; Zhou, Jun; Lin, Yaofa; Xie, Zheng; Chen, Huihao; Yu, Ronghua; Lin, Haodong; Hou, Chunlin

    2018-07-01

    Quadriceps palsy is mainly caused by proximal lesions in the femoral nerve. The obturator nerve has been previously used to repair the femoral nerve, although only a few reports have described the procedure, and the outcomes have varied. In the present study, we aimed to confirm the feasibility and effectiveness of this treatment in a rodent model using the randomized control method. Sixty Sprague-Dawley rats were randomized into two groups: the experimental group, wherein rats underwent femoral neurectomy and obturator nerve transfer to the femoral nerve motor branch; and the control group, wherein rats underwent femoral neurectomy without nerve transfer. Functional outcomes were measured using the BBB score, muscle mass, and histological assessment. At 12 and 16 weeks postoperatively, the rats in the experimental group exhibited recovery to a stronger stretch force of the knee and higher BBB score, as compared to the control group (p < 0.05). The muscle mass and myofiber cross-sectional area of the quadriceps were heavier and larger than those in the control group (p < 0.05). A regenerated nerve with myelinated and unmyelinated fibers was observed in the experimental group. No significant differences were observed between groups at 8 weeks postoperatively (p > 0.05). Obturator nerve transfer for repairing femoral nerve injury was feasible and effective in a rat model, and can hence be considered as an option for the treatment of femoral nerve injury.

  13. Correcting highly aberrated eyes using large-stroke adaptive optics.

    PubMed

    Sabesan, Ramkumar; Ahmad, Kamran; Yoon, Geunyoung

    2007-11-01

    To investigate the optical performance of a large-stroke deformable mirror in correcting large aberrations in highly aberrated eyes. A large-stroke deformable mirror (Mirao 52D; Imagine Eyes) and a Shack-Hartmann wavefront sensor were used in an adaptive optics system. Closed-loop correction of the static aberrations of a phase plate designed for an advanced keratoconic eye was performed for a 6-mm pupil. The same adaptive optics system was also used to correct the aberrations in one eye each of two moderate keratoconic and three normal human eyes for a 6-mm pupil. With closed-loop correction of the phase plate, the total root-mean-square (RMS) over a 6-mm pupil was reduced from 3.54 to 0.04 microm in 30 to 40 iterations, corresponding to 3 to 4 seconds. Adaptive optics closed-loop correction reduced an average total RMS of 1.73+/-0.998 to 0.10+/-0.017 microm (higher order RMS of 0.39+/-0.124 to 0.06+/-0.004 microm) in the three normal eyes and 2.73+/-1.754 to 0.10+/-0.001 microm (higher order RMS of 1.82+/-1.058 to 0.05+/-0.017 microm) in the two keratoconic eyes. Aberrations in both normal and highly aberrated eyes were successfully corrected using the large-stroke deformable mirror to provide almost perfect optical quality. This mirror can be a powerful tool to assess the limit of visual performance achievable after correcting the aberrations, especially in eyes with abnormal corneal profiles.

  14. Subjective face recognition difficulties, aberrant sensibility, sleeping disturbances and aberrant eating habits in families with Asperger syndrome

    PubMed Central

    Nieminen-von Wendt, Taina; Paavonen, Juulia E; Ylisaukko-Oja, Tero; Sarenius, Susan; Källman, Tiia; Järvelä, Irma; von Wendt, Lennart

    2005-01-01

    Background The present study was undertaken in order to determine whether a set of clinical features, which are not included in the DSM-IV or ICD-10 for Asperger Syndrome (AS), are associated with AS in particular or whether they are merely a familial trait that is not related to the diagnosis. Methods Ten large families, a total of 138 persons, of whom 58 individuals fulfilled the diagnostic criteria for AS and another 56 did not to fulfill these criteria, were studied using a structured interview focusing on the possible presence of face recognition difficulties, aberrant sensibility and eating habits and sleeping disturbances. Results The prevalence for face recognition difficulties was 46.6% in individuals with AS compared with 10.7% in the control group. The corresponding figures for subjectively reported presence of aberrant sensibilities were 91.4% and 46.6%, for sleeping disturbances 48.3% and 23.2% and for aberrant eating habits 60.3% and 14.3%, respectively. Conclusion An aberrant processing of sensory information appears to be a common feature in AS. The impact of these and other clinical features that are not incorporated in the ICD-10 and DSM-IV on our understanding of AS may hitherto have been underestimated. These associated clinical traits may well be reflected by the behavioural characteristics of these individuals. PMID:15826308

  15. Spectral estimation for characterization of acoustic aberration.

    PubMed

    Varslot, Trond; Angelsen, Bjørn; Waag, Robert C

    2004-07-01

    Spectral estimation based on acoustic backscatter from a motionless stochastic medium is described for characterization of aberration in ultrasonic imaging. The underlying assumptions for the estimation are: The correlation length of the medium is short compared to the length of the transmitted acoustic pulse, an isoplanatic region of sufficient size exists around the focal point, and the backscatter can be modeled as an ergodic stochastic process. The motivation for this work is ultrasonic imaging with aberration correction. Measurements were performed using a two-dimensional array system with 80 x 80 transducer elements and an element pitch of 0.6 mm. The f number for the measurements was 1.2 and the center frequency was 3.0 MHz with a 53% bandwidth. Relative phase of aberration was extracted from estimated cross spectra using a robust least-mean-square-error method based on an orthogonal expansion of the phase differences of neighboring wave forms as a function of frequency. Estimates of cross-spectrum phase from measurements of random scattering through a tissue-mimicking aberrator have confidence bands approximately +/- 5 degrees wide. Both phase and magnitude are in good agreement with a reference characterization obtained from a point scatterer.

  16. Morphological differences in skeletal muscle atrophy of rats with motor nerve and/or sensory nerve injury★

    PubMed Central

    Zhao, Lei; Lv, Guangming; Jiang, Shengyang; Yan, Zhiqiang; Sun, Junming; Wang, Ling; Jiang, Donglin

    2012-01-01

    Skeletal muscle atrophy occurs after denervation. The present study dissected the rat left ventral root and dorsal root at L4-6 or the sciatic nerve to establish a model of simple motor nerve injury, sensory nerve injury or mixed nerve injury. Results showed that with prolonged denervation time, rats with simple motor nerve injury, sensory nerve injury or mixed nerve injury exhibited abnormal behavior, reduced wet weight of the left gastrocnemius muscle, decreased diameter and cross-sectional area and altered ultrastructure of muscle cells, as well as decreased cross-sectional area and increased gray scale of the gastrocnemius muscle motor end plate. Moreover, at the same time point, the pathological changes were most severe in mixed nerve injury, followed by simple motor nerve injury, and the changes in simple sensory nerve injury were the mildest. These findings indicate that normal skeletal muscle morphology is maintained by intact innervation. Motor nerve injury resulted in larger damage to skeletal muscle and more severe atrophy than sensory nerve injury. Thus, reconstruction of motor nerves should be considered first in the clinical treatment of skeletal muscle atrophy caused by denervation. PMID:25337102

  17. Statistical virtual eye model based on wavefront aberration

    PubMed Central

    Wang, Jie-Mei; Liu, Chun-Ling; Luo, Yi-Ning; Liu, Yi-Guang; Hu, Bing-Jie

    2012-01-01

    Wavefront aberration affects the quality of retinal image directly. This paper reviews the representation and reconstruction of wavefront aberration, as well as the construction of virtual eye model based on Zernike polynomial coefficients. In addition, the promising prospect of virtual eye model is emphasized. PMID:23173112

  18. Double-pass measurement of human eye aberrations: limitations and practical realization

    NASA Astrophysics Data System (ADS)

    Letfullin, Renat R.; Belyakov, Alexey I.; Cherezova, Tatyana Y.; Kudryashov, Alexis V.

    2004-11-01

    The problem of correct eye aberrations measurement is very important with the rising widespread of a surgical procedure for reducing refractive error in the eye, so called, LASIK (laser-assisted in situ keratomileusis). The double-pass technique commonly used for measuring aberrations of a human eye involves some uncertainties. One of them is loosing the information about odd human eye aberrations. We report about investigations of the applicability limit of the double-pass measurements depending upon the aberrations status introduced by human eye and actual size of the entrance pupil. We evaluate the double-pass effects for various aberrations and different pupil diameters. It is shown that for small pupils the double-pass effects are negligible. The testing and alignment of aberrometer was performed using the schematic eye, developed in our lab. We also introduced a model of human eye based on bimorph flexible mirror. We perform calculations to demonstrate that our schematic eye is capable of reproducing spatial-temporal statistics of aberrations of living eye with normal vision or even myopic or hypermetropic or with high aberrations ones.

  19. Using aberrant behaviors as reinforcers for autistic children.

    PubMed Central

    Charlop, M H; Kurtz, P F; Casey, F G

    1990-01-01

    In a series of experiments, we assessed the efficacy of using autistic children's aberrant behaviors as reinforcers to increase their correct task responding. In Experiment 1, reinforcer conditions of stereotypy, food, and varied (food or stereotypy) were compared. In Experiment 2, the conditions were delayed echolalia, food, and varied (food or delayed echolalia), and in Experiment 3, perseverative behavior was compared with stereotypy and food as potential reinforcers. A multielement design was used for all comparisons, and side-effect measures were recorded during and after teaching sessions as well as at home. Results indicated that, in general, task performance was highest when brief opportunities to engage in aberrant behaviors were provided as reinforcers. Edibles were associated with the lowest performance. Furthermore, no negative side effects (e.g., an increase in aberrant behaviors) occurred. The results are discussed in terms of suggesting a more pragmatic treatment approach by addressing the contingent use of autistic children's aberrant behaviors as reinforcers. PMID:2373653

  20. Recent advances in nerve tissue engineering.

    PubMed

    Zhang, Bill G X; Quigley, Anita F; Myers, Damian E; Wallace, Gordon G; Kapsa, Robert M I; Choong, Peter F M

    2014-04-01

    Nerve injury secondary to trauma, neurological disease or tumor excision presents a challenge for surgical reconstruction. Current practice for nerve repair involves autologous nerve transplantation, which is associated with significant donor-site morbidity and other complications. Previously artificial nerve conduits made from polycaprolactone, polyglycolic acid and collagen were approved by the FDA (USA) for nerve repair. More recently, there have been significant advances in nerve conduit design that better address the requirements of nerve regrowth. Innovations in materials science, nanotechnology, and biology open the way for the synthesis of new generation nerve repair conduits that address issues currently faced in nerve repair and regeneration. This review discusses recent innovations in this area, including the use of nanotechnology to improve the design of nerve conduits and to enhance nerve regeneration.

  1. Ulnar nerve damage (image)

    MedlinePlus

    The ulnar nerve originates from the brachial plexus and travels down arm. The nerve is commonly injured at the elbow because of elbow fracture or dislocation. The ulnar nerve is near the surface of the body where ...

  2. Chondromyxoid fibroma of the mastoid facial nerve canal mimicking a facial nerve schwannoma.

    PubMed

    Thompson, Andrew L; Bharatha, Aditya; Aviv, Richard I; Nedzelski, Julian; Chen, Joseph; Bilbao, Juan M; Wong, John; Saad, Reda; Symons, Sean P

    2009-07-01

    Chondromyxoid fibroma of the skull base is a rare entity. Involvement of the temporal bone is particularly rare. We present an unusual case of progressive facial nerve paralysis with imaging and clinical findings most suggestive of a facial nerve schwannoma. The lesion was tubular in appearance, expanded the mastoid facial nerve canal, protruded out of the stylomastoid foramen, and enhanced homogeneously. The only unusual imaging feature was minor calcification within the tumor. Surgery revealed an irregular, cystic lesion. Pathology diagnosed a chondromyxoid fibroma involving the mastoid portion of the facial nerve canal, destroying the facial nerve.

  3. Femoral nerve damage (image)

    MedlinePlus

    The femoral nerve is located in the leg and supplies the muscles that assist help straighten the leg. It supplies sensation ... leg. One risk of damage to the femoral nerve is pelvic fracture. Symptoms of femoral nerve damage ...

  4. Ocular Chromatic Aberrations and Their Effects on Polychromatic Retinal Image Quality

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaoxiao

    Previous studies of ocular chromatic aberrations have concentrated on chromatic difference of focus (CDF). Less is known about the chromatic difference of image position (CDP) in the peripheral retina and no experimental attempt has been made to measure the ocular chromatic difference of magnification (CDM). Consequently, theoretical modelling of human eyes is incomplete. The insufficient knowledge of ocular chromatic aberrations is partially responsible for two unsolved applied vision problems: (1) how to improve vision by correcting ocular chromatic aberration? (2) what is the impact of ocular chromatic aberration on the use of isoluminance gratings as a tool in spatial-color vision?. Using optical ray tracing methods, MTF analysis methods of image quality, and psychophysical methods, I have developed a more complete model of ocular chromatic aberrations and their effects on vision. The ocular CDM was determined psychophysically by measuring the tilt in the apparent frontal parallel plane (AFPP) induced by interocular difference in image wavelength. This experimental result was then used to verify a theoretical relationship between the ocular CDM, the ocular CDF and the entrance pupil of the eye. In the retinal image after correcting the ocular CDF with existing achromatizing methods, two forms of chromatic aberration (CDM and chromatic parallax) were examined. The CDM was predicted by theoretical ray tracing and measured with the same method used to determine ocular CDM. The chromatic parallax was predicted with a nodal ray model and measured with the two-color vernier alignment method. The influence of these two aberrations on polychromatic MTF were calculated. Using this improved model of ocular chromatic aberration, luminance artifacts in the images of isoluminance gratings were calculated. The predicted luminance artifacts were then compared with experimental data from previous investigators. The results show that: (1) A simple relationship exists between

  5. Normal and sonographic anatomy of selected peripheral nerves. Part III: Peripheral nerves of the lower limb.

    PubMed

    Kowalska, Berta; Sudoł-Szopińska, Iwona

    2012-06-01

    The ultrasonographic examination is currently increasingly used in imaging peripheral nerves, serving to supplement the physical examination, electromyography and magnetic resonance imaging. As in the case of other USG imaging studies, the examination of peripheral nerves is non-invasive and well-tolerated by patients. The typical ultrasonographic picture of peripheral nerves as well as the examination technique have been discussed in part I of this article series, following the example of the median nerve. Part II of the series presented the normal anatomy and the technique for examining the peripheral nerves of the upper limb. This part of the article series focuses on the anatomy and technique for examining twelve normal peripheral nerves of the lower extremity: the iliohypogastric and ilioinguinal nerves, the lateral cutaneous nerve of the thigh, the pudendal, sciatic, tibial, sural, medial plantar, lateral plantar, common peroneal, deep peroneal and superficial peroneal nerves. It includes diagrams showing the proper positioning of the sonographic probe, plus USG images of the successively discussed nerves and their surrounding structures. The ultrasonographic appearance of the peripheral nerves in the lower limb is identical to the nerves in the upper limb. However, when imaging the lower extremity, convex probes are more often utilized, to capture deeply-seated nerves. The examination technique, similarly to that used in visualizing the nerves of upper extremity, consists of locating the nerve at a characteristic anatomic reference point and tracking it using the "elevator technique". All 3 parts of the article series should serve as an introduction to a discussion of peripheral nerve pathologies, which will be presented in subsequent issues of the "Journal of Ultrasonography".

  6. Normal and sonographic anatomy of selected peripheral nerves. Part III: Peripheral nerves of the lower limb

    PubMed Central

    Sudoł-Szopińska, Iwona

    2012-01-01

    The ultrasonographic examination is currently increasingly used in imaging peripheral nerves, serving to supplement the physical examination, electromyography and magnetic resonance imaging. As in the case of other USG imaging studies, the examination of peripheral nerves is non-invasive and well-tolerated by patients. The typical ultrasonographic picture of peripheral nerves as well as the examination technique have been discussed in part I of this article series, following the example of the median nerve. Part II of the series presented the normal anatomy and the technique for examining the peripheral nerves of the upper limb. This part of the article series focuses on the anatomy and technique for examining twelve normal peripheral nerves of the lower extremity: the iliohypogastric and ilioinguinal nerves, the lateral cutaneous nerve of the thigh, the pudendal, sciatic, tibial, sural, medial plantar, lateral plantar, common peroneal, deep peroneal and superficial peroneal nerves. It includes diagrams showing the proper positioning of the sonographic probe, plus USG images of the successively discussed nerves and their surrounding structures. The ultrasonographic appearance of the peripheral nerves in the lower limb is identical to the nerves in the upper limb. However, when imaging the lower extremity, convex probes are more often utilized, to capture deeply-seated nerves. The examination technique, similarly to that used in visualizing the nerves of upper extremity, consists of locating the nerve at a characteristic anatomic reference point and tracking it using the “elevator technique”. All 3 parts of the article series should serve as an introduction to a discussion of peripheral nerve pathologies, which will be presented in subsequent issues of the “Journal of Ultrasonography”. PMID:26674560

  7. Orthonormal aberration polynomials for anamorphic optical imaging systems with circular pupils.

    PubMed

    Mahajan, Virendra N

    2012-06-20

    In a recent paper, we considered the classical aberrations of an anamorphic optical imaging system with a rectangular pupil, representing the terms of a power series expansion of its aberration function. These aberrations are inherently separable in the Cartesian coordinates (x,y) of a point on the pupil. Accordingly, there is x-defocus and x-coma, y-defocus and y-coma, and so on. We showed that the aberration polynomials orthonormal over the pupil and representing balanced aberrations for such a system are represented by the products of two Legendre polynomials, one for each of the two Cartesian coordinates of the pupil point; for example, L(l)(x)L(m)(y), where l and m are positive integers (including zero) and L(l)(x), for example, represents an orthonormal Legendre polynomial of degree l in x. The compound two-dimensional (2D) Legendre polynomials, like the classical aberrations, are thus also inherently separable in the Cartesian coordinates of the pupil point. Moreover, for every orthonormal polynomial L(l)(x)L(m)(y), there is a corresponding orthonormal polynomial L(l)(y)L(m)(x) obtained by interchanging x and y. These polynomials are different from the corresponding orthogonal polynomials for a system with rotational symmetry but a rectangular pupil. In this paper, we show that the orthonormal aberration polynomials for an anamorphic system with a circular pupil, obtained by the Gram-Schmidt orthogonalization of the 2D Legendre polynomials, are not separable in the two coordinates. Moreover, for a given polynomial in x and y, there is no corresponding polynomial obtained by interchanging x and y. For example, there are polynomials representing x-defocus, balanced x-coma, and balanced x-spherical aberration, but no corresponding y-aberration polynomials. The missing y-aberration terms are contained in other polynomials. We emphasize that the Zernike circle polynomials, although orthogonal over a circular pupil, are not suitable for an anamorphic system as

  8. Numerical analysis of wavefront aberration correction using multielectrode electrowetting-based devices.

    PubMed

    Zohrabi, Mo; Cormack, Robert H; Mccullough, Connor; Supekar, Omkar D; Gibson, Emily A; Bright, Victor M; Gopinath, Juliet T

    2017-12-11

    We present numerical simulations of multielectrode electrowetting devices used in a novel optical design to correct wavefront aberration. Our optical system consists of two multielectrode devices, preceded by a single fixed lens. The multielectrode elements function as adaptive optical devices that can be used to correct aberrations inherent in many imaging setups, biological samples, and the atmosphere. We are able to accurately simulate the liquid-liquid interface shape using computational fluid dynamics. Ray tracing analysis of these surfaces shows clear evidence of aberration correction. To demonstrate the strength of our design, we studied three different input aberrations mixtures that include astigmatism, coma, trefoil, and additional higher order aberration terms, with amplitudes as large as one wave at 633 nm.

  9. Phrenic and intercostal nerves with rhythmic discharge can promote early nerve regeneration after brachial plexus repair in rats.

    PubMed

    Rui, Jing; Xu, Ya-Li; Zhao, Xin; Li, Ji-Feng; Gu, Yu-Dong; Lao, Jie

    2018-05-01

    Exogenous discharge can positively promote nerve repair. We, therefore, hypothesized that endogenous discharges may have similar effects. The phrenic nerve and intercostal nerve, controlled by the respiratory center, can emit regular nerve impulses; therefore these endogenous automatically discharging nerves might promote nerve regeneration. Action potential discharge patterns were examined in the diaphragm, external intercostal and latissimus dorsi muscles of rats. The phrenic and intercostal nerves showed rhythmic clusters of discharge, which were consistent with breathing frequency. From the first to the third intercostal nerves, spontaneous discharge amplitude was gradually increased. There was no obvious rhythmic discharge in the thoracodorsal nerve. Four animal groups were performed in rats as the musculocutaneous nerve cut and repaired was bland control. The other three groups were followed by a side-to-side anastomosis with the phrenic nerve, intercostal nerve and thoracodorsal nerve. Compound muscle action potentials in the biceps muscle innervated by the musculocutaneous nerve were recorded with electrodes. The tetanic forces of ipsilateral and contralateral biceps muscles were detected by a force displacement transducer. Wet muscle weight recovery rate was measured and pathological changes were observed using hematoxylin-eosin staining. The number of nerve fibers was observed using toluidine blue staining and changes in nerve ultrastructure were observed using transmission electron microscopy. The compound muscle action potential amplitude was significantly higher at 1 month after surgery in phrenic and intercostal nerve groups compared with the thoracodorsal nerve and blank control groups. The recovery rate of tetanic tension and wet weight of the right biceps were significantly lower at 2 months after surgery in the phrenic nerve, intercostal nerve, and thoracodorsal nerve groups compared with the negative control group. The number of myelinated axons

  10. Electrophysiological Assessment of a Peptide Amphiphile Nanofiber Nerve Graft for Facial Nerve Repair.

    PubMed

    Greene, Jacqueline J; McClendon, Mark T; Stephanopoulos, Nicholas; Álvarez, Zaida; Stupp, Samuel I; Richter, Claus-Peter

    2018-04-27

    Facial nerve injury can cause severe long-term physical and psychological morbidity. There are limited repair options for an acutely transected facial nerve not amenable to primary neurorrhaphy. We hypothesize that a peptide amphiphile nanofiber neurograft may provide the nanostructure necessary to guide organized neural regeneration. Five experimental groups were compared, animals with 1) an intact nerve, 2) following resection of a nerve segment, and following resection and immediate repair with either a 3) autograft (using the resected nerve segment), 4) neurograft, or 5) empty conduit. The buccal branch of the rat facial nerve was directly stimulated with charge balanced biphasic electrical current pulses at different current amplitudes while nerve compound action potentials (nCAPs) and electromygraphic (EMG) responses were recorded. After 8 weeks, the proximal buccal branch was surgically re-exposed and electrically evoked nCAPs were recorded for groups 1-5. As expected, the intact nerves required significantly lower current amplitudes to evoke an nCAP than those repaired with the neurograft and autograft nerves. For other electrophysiologic parameters such as latency and maximum nCAP, there was no significant difference between the intact, autograft and neurograft groups. The resected group had variable responses to electrical stimulation, and the empty tube group was electrically silent. Immunohistochemical analysis and TEM confirmed myelinated neural regeneration. This study demonstrates that the neuroregenerative capability of peptide amphiphile nanofiber neurografts is similar to the current clinical gold standard method of repair and holds potential as an off-the-shelf solution for facial reanimation and potentially peripheral nerve repair. This article is protected by copyright. All rights reserved.

  11. Stability of corneal topography and wavefront aberrations in young Singaporeans.

    PubMed

    Zhu, Mingxia; Collins, Michael J; Yeo, Anna C H

    2013-09-01

    The aim was to investigate the differences between and variations across time in corneal topography and ocular wavefront aberrations in young Singaporean myopes and emmetropes. We used a videokeratoscope and wavefront sensor to measure the ocular surface topography and wavefront aberrations of the total-eye optics in the morning, midday and late afternoon on two separate days. Topographic data were used to derive the corneal surface wavefront aberrations. Both the corneal and total wavefronts were analysed up to the fourth radial order of the Zernike polynomial expansion and were centred on the entrance pupil (5.0 mm). The participants included 12 young progressing myopes, 13 young stable myopes and 15 young age-matched emmetropes. For all subjects considered together, there were significant changes in some of the aberrations across the day, such as spherical aberration ( Z(4 0)) and vertical coma ( Z (3 - 1)) (repeated measures analysis of variance, p < 0.05). The magnitude of positive spherical aberration ( Z(4 0)) was significantly lower in the progressing myopic group than in the stable myopic (p = 0.04) and emmetropic (p = 0.02) groups. There were also significant interactions between refractive group and time of day for with and against-the-rule astigmatism ( Z(2 2)). Significantly lower fourth-order root mean square of ocular wavefront aberrations were found in the progressing myopic group compared with the stable myopes and emmetropes (p < 0.01). These differences and variations in the corneal and total aberrations may have significance for our understanding of refractive error development and for clinical applications requiring accurate wavefront measurements. © 2013 The Authors. Clinical and Experimental Optometry © 2013 Optometrists Association Australia.

  12. Chromosomal aberrations in 2000 couples of Indian ethnicity with reproductive failure.

    PubMed

    Gada Saxena, S; Desai, K; Shewale, L; Ranjan, P; Saranath, D

    2012-08-01

    Constitutional chromosomal aberrations contribute to infertility and repeated miscarriage leading to reproductive failure in couples. These aberrations may show no obvious clinical manifestations and remain undetected across multiple generations. However, infertility or recurrent spontaneous pregnancy loss, and/or genotypic/phenotypic aberrations may be manifested in the progeny during gametogenesis. The current study was a retrospective analysis to examine the chromosomal aberrations and prevalence in 2000 couples of Indian ethnicity with reproductive failure. Cytogenetic analysis via conventional G-band karyotyping analysis was carried out on phytohaemagglutinin stimulated peripheral blood lymphocytes, cultured in RPMI1640 medium. The chromosomes were enumerated as per International System for Human Cytogenetic Nomenclature at 500-550 band resolution, and recorded in the screening sheets. Chromosomal aberrations were detected in a total of 110 (2.78%) couples, with structural chromosomal aberrations in 88 cases including reciprocal translocations in 56 cases, Robertsonian translocations in 16 cases, inversions in eight cases, deletions in three cases, derivative chromosomes in five cases and numerical chromosome aberrations in 23 cases. The study emphasizes the importance of cytogenetic work up in both the partners associated with a history of reproductive failure. Genetic counselling with an option of prenatal diagnosis should be offered to couples with chromosomal aberrations. Copyright © 2012 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

  13. Dimensions of driving anger and their relationships with aberrant driving.

    PubMed

    Zhang, Tingru; Chan, Alan H S; Zhang, Wei

    2015-08-01

    The purpose of this study was to investigate the relationship between driving anger and aberrant driving behaviours. An internet-based questionnaire survey was administered to a sample of Chinese drivers, with driving anger measured by a 14-item short Driving Anger Scale (DAS) and the aberrant driving behaviours measured by a 23-item Driver Behaviour Questionnaire (DBQ). The results of Confirmatory Factor Analysis demonstrated that the three-factor model (hostile gesture, arrival-blocking and safety-blocking) of the DAS fitted the driving anger data well. The Exploratory Factor Analysis on DBQ data differentiated four types of aberrant driving, viz. emotional violation, error, deliberate violation and maintaining progress violation. For the anger-aberration relation, it was found that only "arrival-blocking" anger was a significant positive predictor for all four types of aberrant driving behaviours. The "safety-blocking" anger revealed a negative impact on deliberate violations, a finding different from previously established positive anger-aberration relation. These results suggest that drivers with different patterns of driving anger would show different behavioural tendencies and as a result intervention strategies may be differentially effective for drivers of different profiles. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Ocular wavefront aberration and refractive error in pre-school children

    NASA Astrophysics Data System (ADS)

    Thapa, Damber; Fleck, Andre; Lakshminarayanan, Vasudevan; Bobier, William R.

    2011-11-01

    Hartmann-Shack images taken from an archived collection of SureSight refractive measurements of pre-school children in Oxford County, Ontario, Canada were retrieved and re-analyzed. Higher-order aberrations were calculated over the age range of 3 to 6 years. These higher-order aberrations were compared with respect to magnitudes of ametropia. Subjects were classified as emmetropic (range -0.5 to + 0.5D), low hyperopic (+ 0.5 to +2D) and high hyperopic (+2D or more) based upon the resulting spherical equivalent. Higher-order aberrations were found to increase with higher levels of hyperopia (p < 0.01). The strongest effect was for children showing more than +2.00D of hyperopia. The correlation coefficients were small in all of the higher-order aberrations; however, they were significant (p < 0.01). These analyses indicate a weak association between refractive error and higher-order aberrations in pre-school children.

  15. Dynamic accommodation with simulated targets blurred with high order aberrations

    PubMed Central

    Gambra, Enrique; Wang, Yinan; Yuan, Jing; Kruger, Philip B.; Marcos, Susana

    2010-01-01

    High order aberrations have been suggested to play a role in determining the direction of accommodation. We have explored the effect of retinal blur induced by high order aberrations on dynamic accommodation by measuring the accommodative response to sinusoidal variations in accommodative demand (1–3 D). The targets were blurred with 0.3 and 1 μm (for a 3-mm pupil) of defocus, coma, trefoil and spherical aberration. Accommodative gain decreased significantly when 1-μm of aberration was induced. We found a strong correlation between the relative accommodative gain (and phase lag) and the contrast degradation imposed on the target at relevant spatial frequencies. PMID:20600230

  16. [Immediate recurrent laryngeal nerve reconstruction in the treatment of thyroid cancer invading the recurrent laryngeal nerve].

    PubMed

    Feng, Yun; Yang, Dazhang; Liu, Dandan; Chen, Jian; Bi, Qingling; Luo, Keqiang

    2014-08-01

    To explore the application of immediate recurrent laryngeal nerve reconstruction in the treatment of thyroid cancer invading the recurrent laryngeal nerve. Ten patients with thyroid cancer invading unilateral recurrent laryngeal nerve underwent radical surgery and immediate recurrent laryngeal nerve reconstruction. The reconstructive surgical approach included recurrent laryngeal nerve decompression surgery, end-to-end anastomosis of the recurrent laryngeal nerve, anastomosis of ansa cervicalis nerve to the recurrent laryngeal nerve, and nerve-muscle pedicle (NMP) technique. Among the ten patients, one underwent nerve decompression, one underwent end-to-end anastomosis of the recurrent laryngeal nerve, seven had anastomosis of ansa cervicalis to recurrent laryngeal nerve, and one case had anastomosis of ansa cervicalis to recurrent laryngeal nerve combined with nerve-muscle pedicle (NMP) technique. The effect of surgery was evaluated by videolaryngoscopy, maximum phonation time (MPT), phonation efficiency index (PEI) and voice assessment. T-test was used in the statistical analysis. All of the 10 patients had no complications including tumor recurrence and hypoparathyroidism after the surgery. Their hoarseness symptoms were improved, and the patients returned to normal or near-normal voice. Postoperative videolaryngoscopy showed that paralyzed vocal cord returned to normal muscle tone and volume, and the vocal cord vibration and mucosal wave were symmetric and the patients got good glottal closure. The pre- and post-operative maximum phone times of the patients were (4.52 ± 0.89) s and (11.91 ± 1.87) s, respectively (P < 0.01). The pre- and post-operative phonation efficiency indices were (1.37 ± 0.43) s/L and (4.02 ± 1.33) s/L, respectively (P < 0.05). In patients with thyroid cancer invading unilateral recurrent laryngeal nerve, immediate recurrent laryngeal nerve reconstruction following radical surgery of thyroid cancer can effectively achieve recovery in

  17. Comparison of wavefront aberrations under cycloplegic, scotopic and photopic conditions using WaveScan.

    PubMed

    Fan, Rong; He, Tao; Qiu, Yan; Di, Yu-Lan; Xu, Su-yun; Li, Yao-yu

    2012-01-01

    To evaluate the differences of wavefront aberrations under cycloplegic, scotopic and photopic conditions. A total of 174 eyes of 105 patients were measured using the wavefront sensor (WaveScan® 3.62) under different pupil conditions: cycloplegic 8.58 ± 0.54 mm (6.4 mm - 9.5 mm), scotopic 7.53 ± 0.69 mm (5.7 mm - 9.1 mm) and photopic 6.08 ± 1.14 mm (4.1 mm - 8.8 mm). The pupil diameter, standard Zernike coefficients, root mean square of higher-order aberrations and dominant aberrations were compared between cycloplegic and scotopic conditions, and between scotopic and photopic conditions. The pupil diameter was 7.53 ± 0.69 mm under the scotopic condition, which reached the requirement of about 6.5 mm optical zone design in the wavefront-guided surgery and prevented measurement error due to the pupil centroid shift caused by mydriatics. Pharmacological pupil dilation induced increase of standard Zernike coefficients Z(3)(-3), Z(4)(0) and Z(5)(-5). The higher-order aberrations, third-order aberration, fourth-order aberration, fifth-order aberration, sixth-order aberration, and spherical aberration increased statistically significantly, compared to the scotopic condition (P<0.010). When the scotopic condition shifted to the photopic condition, the standard Zernike coefficients Z(4)(0), Z(4)(2), Z(6)(-4), Z(6)(-2), Z(6)(2) decreased and all the higher-order aberrations decreased statistically significantly (P<0.010), demonstrating that accommodative miosis can significantly improve vision under the photopic condition. Under the three conditions, the vertical coma aberration appears the most frequently within the dominant aberrations without significant effect by pupil size variance, and the proportion of spherical aberrations decreased with the decrease of the pupil size. The wavefront aberrations are significantly different under cycloplegic, scotopic and photopic conditions. Using the wavefront sensor (VISX WaveScan) to measure scotopic wavefront aberrations is

  18. Aberrant Salience, Self-Concept Clarity, and Interview-Rated Psychotic-Like Experiences

    PubMed Central

    Cicero, David C.; Docherty, Anna R.; Becker, Theresa M.; Martin, Elizabeth A.; Kerns, John G.

    2014-01-01

    Many social-cognitive models of psychotic-like symptoms posit a role for self-concept and aberrant salience. Previous work has shown that the interaction between aberrant salience and self-concept clarity is associated with self-reported psychotic-like experiences. In the current research with two structured interviews, the interaction between aberrant salience and self-concept clarity was found to be associated withinterview-rated psychotic-like experiences. The interaction was associated withpsychotic-like experiences composite scores, delusional ideation, grandiosity, and perceptual anomalies. In all cases, self-concept clarity was negatively associated with psychotic-like experiences at high levels of aberrant salience, but unassociated with psychotic-like experiences at low levels of aberrant salience. The interaction was specific to positive psychotic-like experiences and not present for negative or disorganized ratings. The interaction was not mediated by self-esteem levels. These results provide further evidence that aberrant salience and self-concept clarity play an important role in the generation of psychotic-like experiences. PMID:25102085

  19. Recurrent branchial sinus tract with aberrant extension.

    PubMed

    Barret, J P

    2004-01-01

    Second branchial cysts are the commonest lesions among congenital lateral neck anomalies. Good knowledge of anatomy and embryology are necessary for proper treatment. Surgical treatment involves resection of all branchial remnants, which extend laterally in the neck, medial to the sternocleidomastoid muscle with cranial extension to the pharynx and ipsilateral tonsillar fosa. However, infections and previous surgery can distort anatomy, making the approach to branchial anomalies more difficult. We present a case of a 17-year-old patient who presented with a second branchial tract anomaly with an aberrant extension to the midline and part of the contralateral neck. Previous surgical interventions and chronic infections may have been the primary cause for this aberrant tract. All head and neck surgeons should bear in mind that aberrant presentations may exist when reoperating on chronic branchial cysts fistulas.

  20. Chromosomal aberrations in peripheral lymphocytes of train engine drivers.

    PubMed

    Nordenson, I; Mild, K H; Järventaus, H; Hirvonen, A; Sandström, M; Wilén, J; Blix, N; Norppa, H

    2001-07-01

    Studies of Swedish railway employees have indicated that railroad engine drivers have an increased cancer morbidity and incidence of chronic lymphatic leukemia. The drivers are exposed to relatively high magnetic fields (MF), ranging from a few to over a hundred microT. Although the possible genotoxic potential of MF is unclear, some earlier studies have indicated that occupational exposure to MF may increase chromosome aberrations in blood lymphocytes. Since an increased level of chromosomal aberrations has been suggested to predict elevated cancer risk, we performed a cytogenetic analysis on cultured (48 h) peripheral lymphocytes of Swedish train engine drivers. A pilot study of 18 engine drivers indicated a significant difference in the frequency of cells with chromosomal aberrations (gaps included or excluded) in comparison with seven concurrent referents (train dispatchers) and a control group of 16 office workers. The engine drivers had about four times higher frequency of cells with chromosome-type aberrations (excluding gaps) than the office workers (P < 0.01) and the dispatchers (P < 0.05). Seventy-eight percent of the engine drivers showed at least one cell per 100 with chromosome-type aberrations compared with 29% among the dispatchers and 31% among the office workers. In a follow-up study, another 30 engine drivers showed an increase (P < 0.05) in the frequency of cells with chromosome-type aberrations (gaps excluded) as compared with 30 referent policemen. Sixty percent of the engine drivers had one or more cells (per 100 cells) with chromosome-type aberrations compared with 30% among the policemen. In conclusion, the results of the two studies support the hypothesis that exposure to MF at mean intensities of 2-15 microT can induce chromosomal damage. Copyright 2001 Wiley-Liss, Inc.

  1. In vivo longitudinal chromatic aberration of pseudophakic eyes.

    PubMed

    Siedlecki, Damian; Jóźwik, Agnieszka; Zając, Marek; Hill-Bator, Aneta; Turno-Kręcicka, Anna

    2014-02-01

    To present the results of longitudinal chromatic aberration measurements on two groups of pseudophakic eyes in comparison to healthy eyes. The longitudinal chromatic aberration of the eye, defined as chromatic difference of refraction with disabled accommodation, was measured with the use of a visual refractometer with a custom-designed target illuminator consisting of a narrow-band RGB diode (blue λb = 470 ± 15 nm; green λg = 525 ± 18 nm; red λr = 660 ± 10 nm). The measurements were performed on nine eyes implanted with AcrySof IQ SN60WF, 14 eyes implanted with AcrySof SA60AT, and 10 phakic eyes under cycloplegia. The mean values of the longitudinal chromatic aberration between 470 and 660 nm for the control group was 1.12 ± 0.14 D. For SA60AT group, it was 1.45 ± 0.42 D whereas for SN60WF it was 1.17 ± 0.52 D. The statistical test showed significant difference between SA60AT and the control group (p < 0.05) and no significant difference between SN60WF and the control groups (p = 0.64). The study showed that the longitudinal chromatic aberration in vivo can be easily and reliably estimated with an adapted visual refractometer. The two groups of pseudophakic eyes measured in this study showed different values of chromatic aberration. Its magnitude for SA60AT group was significantly larger than for the control group whereas for SN60WF the difference was not significant. The optical material used for intraocular lens design may have significant influence on the magnitude of the chromatic aberration of the pseudophakic eye, and therefore on its optical and visual performance in polychromatic light.

  2. Modified Matching Ronchi Test to Visualize Lens Aberrations

    ERIC Educational Resources Information Center

    Hassani, Kh; Ziafi, H. Hooshmand

    2011-01-01

    We introduce a modification to the matching Ronchi test to visualize lens aberrations with simple and inexpensive equipment available in educational optics labs. This method can help instructors and students to observe and estimate lens aberrations in real time. It is also a semi-quantitative tool for primary tests in research labs. In this work…

  3. Sextupole system for the correction of spherical aberration

    DOEpatents

    Crewe, A.V.; Kopf, D.A.

    In an electron beam device in which an electron beam is developed and then focused by a lens to a particular spot, there is provided a means for eliminating spherical aberration. A sextupole electromagnetic lens is positioned between two focusing lenses. The interaction of the sextupole with the beam compensates for spherical aberration. (GHT)

  4. Persistence of Early Emerging Aberrant Behavior in Children with Developmental Disabilities

    ERIC Educational Resources Information Center

    Green, Vanessa A.; O'Reilly, Mark; Itchon, Jonathan; Sigafoos, Jeff

    2005-01-01

    This study examined the persistence of early emerging aberrant behavior in 13 preschool children with developmental disabilities. The severity of aberrant behavior was assessed every 6 months over a 3-year period. Teachers completed the assessments using the Aberrant Behavior Checklist [Aman, M. G., & Singh, N. N. (1986). "Aberrant…

  5. Brillouin micro-spectroscopy through aberrations via sensorless adaptive optics

    NASA Astrophysics Data System (ADS)

    Edrei, Eitan; Scarcelli, Giuliano

    2018-04-01

    Brillouin spectroscopy is a powerful optical technique for non-contact viscoelastic characterizations which has recently found applications in three-dimensional mapping of biological samples. Brillouin spectroscopy performances are rapidly degraded by optical aberrations and have therefore been limited to homogenous transparent samples. In this work, we developed an adaptive optics (AO) configuration designed for Brillouin scattering spectroscopy to engineer the incident wavefront and correct for aberrations. Our configuration does not require direct wavefront sensing and the injection of a "guide-star"; hence, it can be implemented without the need for sample pre-treatment. We used our AO-Brillouin spectrometer in aberrated phantoms and biological samples and obtained improved precision and resolution of Brillouin spectral analysis; we demonstrated 2.5-fold enhancement in Brillouin signal strength and 1.4-fold improvement in axial resolution because of the correction of optical aberrations.

  6. Reconstruction of the Abdominal Vagus Nerve Using Sural Nerve Grafts in Canine Models

    PubMed Central

    Luo, Fen; Wang, Zhiming; Wang, Yin

    2013-01-01

    Background Recently, vagus nerve preservation or reconstruction of vagus has received increasing attention. The present study aimed to investigate the feasibility of reconstructing the severed vagal trunk using an autologous sural nerve graft. Methods Ten adult Beagle dogs were randomly assigned to two groups of five, the nerve grafting group (TG) and the vagal resection group (VG). The gastric secretion and emptying functions in both groups were assessed using Hollander insulin and acetaminophen tests before surgery and three months after surgery. All dogs underwent laparotomy under general anesthesia. In TG group, latency and conduction velocity of the action potential in a vagal trunk were measured, and then nerves of 4 cm long were cut from the abdominal anterior and posterior vagal trunks. Two segments of autologous sural nerve were collected for performing end-to-end anastomoses with the cut ends of vagal trunk (8–0 nylon suture, 3 sutures for each anastomosis). Dogs in VG group only underwent partial resections of the anterior and posterior vagal trunks. Laparotomy was performed in dogs of TG group, and latency and conduction velocity of the action potential in their vagal trunks were measured. The grafted nerve segment was removed, and stained with anti-neurofilament protein and toluidine blue. Results Latency of the action potential in the vagal trunk was longer after surgery than before surgery in TG group, while the conduction velocity was lower after surgery. The gastric secretion and emptying functions were weaker after surgery in dogs of both groups, but in TG group they were significantly better than in VG group. Anti-neurofilament protein staining and toluidine blue staining showed there were nerve fibers crossing the anastomosis of the vagus and sural nerves in dogs of TG group. Conclusion Reconstruction of the vagus nerve using the sural nerve is technically feasible. PMID:23555604

  7. A model of distributed phase aberration for deblurring phase estimated from scattering.

    PubMed

    Tillett, Jason C; Astheimer, Jeffrey P; Waag, Robert C

    2010-01-01

    Correction of aberration in ultrasound imaging uses the response of a point reflector or its equivalent to characterize the aberration. Because a point reflector is usually unavailable, its equivalent is obtained using statistical methods, such as processing reflections from multiple focal regions in a random medium. However, the validity of methods that use reflections from multiple points is limited to isoplanatic patches for which the aberration is essentially the same. In this study, aberration is modeled by an offset phase screen to relax the isoplanatic restriction. Methods are developed to determine the depth and phase of the screen and to use the model for compensation of aberration as the beam is steered. Use of the model to enhance the performance of the noted statistical estimation procedure is also described. Experimental results obtained with tissue-mimicking phantoms that implement different models and produce different amounts of aberration are presented to show the efficacy of these methods. The improvement in b-scan resolution realized with the model is illustrated. The results show that the isoplanatic patch assumption for estimation of aberration can be relaxed and that propagation-path characteristics and aberration estimation are closely related.

  8. Ultrasound-guided approach for axillary brachial plexus, femoral nerve, and sciatic nerve blocks in dogs.

    PubMed

    Campoy, Luis; Bezuidenhout, Abraham J; Gleed, Robin D; Martin-Flores, Manuel; Raw, Robert M; Santare, Carrie L; Jay, Ariane R; Wang, Annie L

    2010-03-01

    To describe an ultrasound-guided technique and the anatomical basis for three clinically useful nerve blocks in dogs. Prospective experimental trial. Four hound-cross dogs aged 2 +/- 0 years (mean +/- SD) weighing 30 +/- 5 kg and four Beagles aged 2 +/- 0 years and weighing 8.5 +/- 0.5 kg. Axillary brachial plexus, femoral, and sciatic combined ultrasound/electrolocation-guided nerve blocks were performed sequentially and bilaterally using a lidocaine solution mixed with methylene blue. Sciatic nerve blocks were not performed in the hounds. After the blocks, the dogs were euthanatized and each relevant site dissected. Axillary brachial plexus block Landmark blood vessels and the roots of the brachial plexus were identified by ultrasound in all eight dogs. Anatomical examination confirmed the relationship between the four ventral nerve roots (C6, C7, C8, and T1) and the axillary vessels. Three roots (C7, C8, and T1) were adequately stained bilaterally in all dogs. Femoral nerve block Landmark blood vessels (femoral artery and femoral vein), the femoral and saphenous nerves and the medial portion of the rectus femoris muscle were identified by ultrasound in all dogs. Anatomical examination confirmed the relationship between the femoral vessels, femoral nerve, and the rectus femoris muscle. The femoral nerves were adequately stained bilaterally in all dogs. Sciatic nerve block. Ultrasound landmarks (semimembranosus muscle, the fascia of the biceps femoris muscle and the sciatic nerve) could be identified in all of the dogs. In the four Beagles, anatomical examination confirmed the relationship between the biceps femoris muscle, the semimembranosus muscle, and the sciatic nerve. In the Beagles, all but one of the sciatic nerves were stained adequately. Ultrasound-guided needle insertion is an accurate method for depositing local anesthetic for axillary brachial plexus, femoral, and sciatic nerve blocks.

  9. Refractive Changes Induced by Spherical Aberration in Laser Correction Procedures: An Adaptive Optics Study.

    PubMed

    Amigó, Alfredo; Martinez-Sorribes, Paula; Recuerda, Margarita

    2017-07-01

    To study the effect on vision of induced negative and positive spherical aberration within the range of laser vision correction procedures. In 10 eyes (mean age: 35.8 years) under cyclopegic conditions, spherical aberration values from -0.75 to +0.75 µm in 0.25-µm steps were induced by an adaptive optics system. Astigmatism and spherical refraction were corrected, whereas the other natural aberrations remained untouched. Visual acuity, depth of focus defined as the interval of vision for which the target was still perceived acceptable, contrast sensitivity, and change in spherical refraction associated with the variation in pupil diameter from 6 to 2.5 mm were measured. A refractive change of 1.60 D/µm of induced spherical aberration was obtained. Emmetropic eyes became myopic when positive spherical aberration was induced and hyperopic when negative spherical aberration was induced (R 2 = 81%). There were weak correlations between spherical aberration and visual acuity or depth of focus (R 2 = 2% and 3%, respectively). Contrast sensitivity worsened with the increment of spherical aberration (R 2 = 59%). When pupil size decreased, emmetropic eyes became hyperopic when preexisting spherical aberration was positive and myopic when spherical aberration was negative, with an average refractive change of 0.60 D/µm of spherical aberration (R 2 = 54%). An inverse linear correlation exists between the refractive state of the eye and spherical aberration induced within the range of laser vision correction. Small values of spherical aberration do not worsen visual acuity or depth of focus, but positive spherical aberration may induce night myopia. In addition, the changes in spherical refraction when the pupil constricts may worsen near vision when positive spherical aberration is induced or improve it when spherical aberration is negative. [J Refract Surg. 2017;33(7):470-474.]. Copyright 2017, SLACK Incorporated.

  10. Surgical and healing changes to ocular aberrations following refractive surgery

    NASA Astrophysics Data System (ADS)

    Straub, Jochen; Schwiegerling, Jim

    2003-07-01

    Purpose: To measure ocular aberrations before and at several time periods after LASIK surgery to determine the change to the aberration structure of the eye. Methods: A Shack-Hartmann wavefront sensor was used to measure 88 LASIK patients pre-operatively and at 1 week and 12 months following surgery. Reconstructed wavefront errors are compared to look at induced differences. Manifest refraction was measured at 1 week, 1 month, 3 months, 6 months and 12 months following surgery. Sphere, cylinder, spherical aberration, and pupil diameter are analyzed. Results: A dramatic elevation in spherical aberration is seen following surgery. This elevation appears almost immediately and remains for the duration of the study. A temporary increase in pupil size is seen following surgery. Conclusions: LASIK surgery dramatically reduces defocus and astigmatism in the eye, but simultaneously increases spherical aberration levels. This increase occurs at the time of surgery and is not an effect of the healing response.

  11. Correlation between Post-LASIK Starburst Symptom and Ocular Wavefront Aberrations

    NASA Astrophysics Data System (ADS)

    Liu, Yong-Ji; Mu, Guo-Guang; Wang, Zhao-Qi; Wang-Yan

    2006-06-01

    Monochromatic aberrations in post laser in-situ keratomileusis (LASIK) eyes are measured. The data are categorized into reference group and starburst group according to the visual symptoms. Statistic analysis has been made to find the correlation between the ocular wavefront aberrations and the starburst symptom. The rms aberrations of the 3rd and 4th orders for the starburst group are significantly larger than those for the reference group. The starburst symptom shows a strong correlation with vertical coma, total coma, spherical aberrations. For 3-mm pupil size and 5.8-mm pupil size, the modulation transfer function (MTF) of the starburst group are lower than those of the reference group, but their visual acuities are close. MTF and PSF analyses are made for two groups, and the results are consistent with the statistical analysis, which means the difference between the two groups is mainly due to the third- and fourth-order Zernike aberrations.

  12. Wavefront aberration changes caused by a gradient of increasing accommodation stimuli

    PubMed Central

    Zhou, X-Y; Wang, L; Zhou, X-T; Yu, Z-Q

    2015-01-01

    Purpose The aim of this study was to investigate the wavefront aberration changes in human eyes caused by a gradient of increasing accommodation stimuli. Design This is a prospective, single-site study. Methods Healthy volunteers (n=22) aged 18–28 years whose refraction states were emmetropia or mild myopia, with astigmatism <1 diopter (D), were included in this study. After dilating the right pupil with 0.5% phenylephrine drops, the wavefront aberration of the right eye was measured continuously either without or with 1, 2, 3, 4, 5, or 6D accommodation stimuli (WFA1000B psychophysical aberrometer). The root mean square (RMS) values of the total wavefront aberrations, higher-order aberrations, and 35 individual Zernike aberrations under different accommodation stimuli were calculated and compared. Results The average induced accommodations using 1, 2, 3, 4, 5, or 6D accommodation stimuli were 0.848, 1.626, 2.375, 3.249, 4.181, or 5.085 D, respectively. The RMS of total wavefront aberrations, as well as higher-order aberrations, showed no significant effects with 1–3 D accommodation stimuli, but increased significantly under 4, 5, and 6 D accommodation stimuli compared with relaxed accommodation. Zernike coefficients of significantly decreased with increasing levels of accommodation. Conclusion Higher-order wavefront aberrations in human eyes changed with increased accommodation. These results are consistent with Schachar's accommodation theory. PMID:25341432

  13. Iterative method for in situ measurement of lens aberrations in lithographic tools using CTC-based quadratic aberration model.

    PubMed

    Liu, Shiyuan; Xu, Shuang; Wu, Xiaofei; Liu, Wei

    2012-06-18

    This paper proposes an iterative method for in situ lens aberration measurement in lithographic tools based on a quadratic aberration model (QAM) that is a natural extension of the linear model formed by taking into account interactions among individual Zernike coefficients. By introducing a generalized operator named cross triple correlation (CTC), the quadratic model can be calculated very quickly and accurately with the help of fast Fourier transform (FFT). The Zernike coefficients up to the 37th order or even higher are determined by solving an inverse problem through an iterative procedure from several through-focus aerial images of a specially designed mask pattern. The simulation work has validated the theoretical derivation and confirms that such a method is simple to implement and yields a superior quality of wavefront estimate, particularly for the case when the aberrations are relatively large. It is fully expected that this method will provide a useful practical means for the in-line monitoring of the imaging quality of lithographic tools.

  14. An aberrant carotid artery in the temporal bone with fatal complication.

    PubMed

    Kimura, Yurika; Makino, Nao; Kobayashi, Hitome; Kitamura, Ken

    2016-06-01

    We report the case of an 84-year-old female presenting with an aberrant ICA with cerebral air embolization caused by Eustachian tube air inflation (ETAI). High pressure of air inflation developed because of an aberrant ICA blocking the tympanic orifice of the Eustachian tube, with release of the high-pressure air into the aberrant ICA. It must be kept in mind that complications may occur not only during transtympanic treatment, but also in any treatment, such as ETAI, in aberrant ICA cases. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  15. [Does intraoperative nerve monitoring reduce the rate of recurrent nerve palsies during thyroid surgery?].

    PubMed

    Timmermann, W; Dralle, H; Hamelmann, W; Thomusch, O; Sekulla, C; Meyer, Th; Timm, S; Thiede, A

    2002-05-01

    Two different aspects of the influence of neuromonitoring on the possible reduction of post-operative recurrent laryngeal nerve palsies require critical examination: the nerve identification and the monitoring of it's functions. Due to the additional information from the EMG signals, neuromonitoring is the best method for identifying the nerves as compared to visual identification alone. There are still no randomized studies available that compare the visual and electrophysiological recurrent laryngeal nerve detection in thyroid operations with respect to the postoperative nerve palsies. Nevertheless, comparisons with historical collectives show that a constant low nerve-palsy-rate was achieved with electrophysiological detection in comparison to visual detection. The rate of nerve identification is normally very high and amounts to 99 % in our own patients. The data obtained during the "Quality assurance of benign and malignant Goiter" study show that in hemithyreoidectomy and subtotal resection, lower nerve-palsy-rates are achieved with neuromonitoring as compared to solely visual detection. Following subtotal resection, this discrepancy becomes even statistically significant. While monitoring the nerve functions with the presently used neuromonitoring technique, it is possible to observe the EMG-signal remaining constant or decreasing in volume. Assuming that a constant neuromonitoring signal represents a normal vocal cord, our evaluation shows that there is a small percentage of false negative and positive results. Looking at the permanent recurrent nerve palsy rates, this method has a specificity of 98 %, a sensitivity of 100 %, a positive prognostic value of 10 %, and a negative prognostic value of 100 %. Although an altered neuromonitoring signal can be taken as a clear indication of eventual nerve damage, an absolutely reliable statement about the postoperative vocal cord function is presently not possible with intraoperative neuromonitoring.

  16. Genipin-Cross-Linked Chitosan Nerve Conduits Containing TNF-α Inhibitors for Peripheral Nerve Repair.

    PubMed

    Zhang, Li; Zhao, Weijia; Niu, Changmei; Zhou, Yujie; Shi, Haiyan; Wang, Yalin; Yang, Yumin; Tang, Xin

    2018-07-01

    Tissue engineered nerve grafts (TENGs) are considered a promising alternative to autologous nerve grafting, which is considered the "gold standard" clinical strategy for peripheral nerve repair. Here, we immobilized tumor necrosis factor-α (TNF-α) inhibitors onto a nerve conduit, which was introduced into a chitosan (CS) matrix scaffold utilizing genipin (GP) as the crosslinking agent, to fabricate CS-GP-TNF-α inhibitor nerve conduits. The in vitro release kinetics of TNF-α inhibitors from the CS-GP-TNF-α inhibitor nerve conduits were investigated using high-performance liquid chromatography. The in vivo continuous release profile of the TNF-α inhibitors released from the CS-GP-TNF-α inhibitor nerve conduits was measured using an enzyme-linked immunosorbent assay over 14 days. We found that the amount of TNF-α inhibitors released decreased with time after the bridging of the sciatic nerve defects in rats. Moreover, 4 and 12 weeks after surgery, histological analyses and functional evaluations were carried out to assess the influence of the TENG on regeneration. Immunochemistry performed 4 weeks after grafting to assess early regeneration outcomes revealed that the TENG strikingly promoted axonal outgrowth. Twelve weeks after grafting, the TENG accelerated myelin sheath formation, as well as functional restoration. In general, the regenerative outcomes following TENG more closely paralleled findings observed with autologous grafting than the use of the CS matrix scaffold. Collectively, our data indicate that the CS-GP-TNF-α inhibitor nerve conduits comprised an elaborate system for sustained release of TNF-α inhibitors in vitro, while studies in vivo demonstrated that the TENG could accelerate regenerating axonal outgrowth and functional restoration. The introduction of CS-GP-TNF-α-inhibitor nerve conduits into a scaffold may contribute to an efficient and adaptive immune microenvironment that can be used to facilitate peripheral nerve repair.

  17. Tissue-Engineered Nanofibrous Nerve Grafts for Enhancing the Rate of Nerve Regeneration

    DTIC Science & Technology

    2015-10-01

    structured nanofibrous biodegradable nerve graft system that present ECM protein, neurotrophic factor, and pre-seeded with bone marrow stromal cells in...nanofibrous biodegradable nerve graft system that present extracellular matrix (ECM) protein, nerve growth factor, and pre-seeded with bone marrow stromal...proposed novel structured nanofibrous biodegradable grafts will provide the micro environment, bioactivity, transport features and mechanics ideal for

  18. Pathogenesis of cranial neuropathies in Moebius syndrome: Electrodiagnostic orofacial studies.

    PubMed

    Renault, Francis; Flores-Guevara, Roberto; Sergent, Bernard; Baudon, Jean Jacques; Aouizerate, Jessie; Vazquez, Marie-Paule; Gitiaux, Cyril

    2018-02-09

    We designed a retrospective study of 59 patients with congenital sporadic nonprogressive bilateral facial and abducens palsies. Examinations included needle electromyography (EMG) of facial and oral muscles, facial nerve motor latency and conduction velocity (FNCV), and blink responses (BR). Neurogenic EMG changes were found in 1 or more muscles in 55 of 59 patients, with no abnormal spontaneous activity. EMG changes were homogeneously neurogenic in 17 patients, homogeneously myopathic in 1 patient, and heterogeneous in 41 of 59 patients. Motor latency was increased according to recordings from 52 of 137 facial muscles. An increase of motor latency was not associated with neurogenic EMG (Fischer's test: right, P = 1; left, P = 0.76). FNCV was slowed in 19 of 36 patients. BR was absent bilaterally in 35 of 58 patients; when present, R1 and R2 latencies were normal. Our results support the hypothesis of an early developmental defect localized in motor cranial nerves with spared V-VII internuclear pathways. Muscle Nerve, 2018. © 2018 Wiley Periodicals, Inc.

  19. Lesion Generation Through Ribs Using Histotripsy Therapy Without Aberration Correction

    PubMed Central

    Kim, Yohan; Wang, Tzu-Yin; Xu, Zhen; Cain, Charles A.

    2012-01-01

    This study investigates the feasibility of using high-intensity pulsed therapeutic ultrasound, or histotripsy, to non-invasively generate lesions through the ribs. Histotripsy therapy mechanically ablates tissue through the generation of a cavitation bubble cloud, which occurs when the focal pressure exceeds a certain threshold. We hypothesize that histotripsy can generate precise lesions through the ribs without aberration correction if the main lobe retains its shape and exceeds the cavitation initiation threshold and the secondary lobes remain below the threshold. To test this hypothesis, a 750-kHz focused transducer was used to generate lesions in tissue-mimicking phantoms with and without the presence of rib aberrators. In all cases, 8000 pulses with 16 to 18 MPa peak rarefactional pressure at a repetition frequency of 100 Hz were applied without aberration correction. Despite the high secondary lobes introduced by the aberrators, high-speed imaging showed that bubble clouds were generated exclusively at the focus, resulting in well-confined lesions with comparable dimensions. Collateral damage from secondary lobes was negligible, caused by single bubbles that failed to form a cloud. These results support our hypothesis, suggesting that histotripsy has a high tolerance for aberrated fields and can generate confined focal lesions through rib obstacles without aberration correction. PMID:22083767

  20. Lesion generation through ribs using histotripsy therapy without aberration correction.

    PubMed

    Kim, Yohan; Wang, Tzu-Yin; Xu, Zhen; Cain, Charles A

    2011-11-01

    This study investigates the feasibility of using high-intensity pulsed therapeutic ultrasound, or histotripsy, to non-invasively generate lesions through the ribs. Histotripsy therapy mechanically ablates tissue through the generation of a cavitation bubble cloud, which occurs when the focal pressure exceeds a certain threshold. We hypothesize that histotripsy can generate precise lesions through the ribs without aberration correction if the main lobe retains its shape and exceeds the cavitation initiation threshold and the secondary lobes remain below the threshold. To test this hypothesis, a 750-kHz focused transducer was used to generate lesions in tissue-mimicking phantoms with and without the presence of rib aberrators. In all cases, 8000 pulses with 16 to 18 MPa peak rarefactional pressure at a repetition frequency of 100 Hz were applied without aberration correction. Despite the high secondary lobes introduced by the aberrators, high-speed imaging showed that bubble clouds were generated exclusively at the focus, resulting in well-confined lesions with comparable dimensions. Collateral damage from secondary lobes was negligible, caused by single bubbles that failed to form a cloud. These results support our hypothesis, suggesting that histotripsy has a high tolerance for aberrated fields and can generate confined focal lesions through rib obstacles without aberration correction.

  1. Induction of chromosome aberrations in human cells by charged particles

    NASA Technical Reports Server (NTRS)

    Wu, H.; Durante, M.; George, K.; Yang, T. C.

    1997-01-01

    Chromosome aberrations induced by high-energy charged particles in normal human lymphocytes and human fibroblasts have been investigated. The charged particles included 250 MeV/nucleon protons, 290 MeV/nucleon carbon ions and 1 GeV/nucleon iron ions. The energies of the charged particles were higher than in most of the studies reported in the literature. Lymphocytes were stimulated to grow immediately after irradiation, while fibroblasts were incubated at 37 degrees C for 24 h for repair. Chromosomes were collected at the first mitosis after irradiation and chromosome aberrations were scored using the fluorescence in situ hybridization (FISH) technique with a whole-chromosome 4 probe. Chromosome aberrations were classified as reciprocal exchanges, incomplete exchanges, deletions and complex exchanges. The relative biological effectiveness (RBE) for each type of aberration was calculated by dividing a dose of 4 Gy by the dose of the charged particles producing the same effect as 4 Gy of gamma rays. Results of this study showed that complex aberrations have the highest RBE for radiation of high linear energy transfer (LET) for human lymphocytes, but for fibroblasts, the greatest effect was for incomplete exchanges. For both lymphocytes and fibroblasts, iron ions induced a similar fraction of aberrant cells.

  2. Structural centrosome aberrations sensitize polarized epithelia to basal cell extrusion.

    PubMed

    Ganier, Olivier; Schnerch, Dominik; Nigg, Erich A

    2018-06-01

    Centrosome aberrations disrupt tissue architecture and may confer invasive properties to cancer cells. Here we show that structural centrosome aberrations, induced by overexpression of either Ninein-like protein (NLP) or CEP131/AZI1, sensitize polarized mammalian epithelia to basal cell extrusion. While unperturbed epithelia typically dispose of damaged cells through apical dissemination into luminal cavities, certain oncogenic mutations cause a switch in directionality towards basal cell extrusion, raising the potential for metastatic cell dissemination. Here we report that NLP-induced centrosome aberrations trigger the preferential extrusion of damaged cells towards the basal surface of epithelial monolayers. This switch in directionality from apical to basal dissemination coincides with a profound reorganization of the microtubule cytoskeleton, which in turn prevents the contractile ring repositioning that is required to support extrusion towards the apical surface. While the basal extrusion of cells harbouring NLP-induced centrosome aberrations requires exogenously induced cell damage, structural centrosome aberrations induced by excess CEP131 trigger the spontaneous dissemination of dying cells towards the basal surface from MDCK cysts. Thus, similar to oncogenic mutations, structural centrosome aberrations can favour basal extrusion of damaged cells from polarized epithelia. Assuming that additional mutations may promote cell survival, this process could sensitize epithelia to disseminate potentially metastatic cells. © 2018 The Authors.

  3. Ocular wavefront aberrations in patients with macular diseases

    PubMed Central

    Bessho, Kenichiro; Bartsch, Dirk-Uwe G.; Gomez, Laura; Cheng, Lingyun; Koh, Hyoung Jun; Freeman, William R.

    2009-01-01

    Background There have been reports that by compensating for the ocular aberrations using adaptive optical systems it may be possible to improve the resolution of clinical retinal imaging systems beyond what is now possible. In order to develop such system to observe eyes with retinal disease, understanding of the ocular wavefront aberrations in individuals with retinal disease is required. Methods 82 eyes of 66 patients with macular disease (epiretinal membrane, macular edema, macular hole etc.) and 85 eyes of 51 patients without retinal disease were studied. Using a ray-tracing wavefront device, each eye was scanned at both small and large pupil apertures and Zernike coefficients up to 6th order were acquired. Results In phakic eyes, 3rd order root mean square errors (RMS) in macular disease group were statistically greater than control, an average of 12% for 5mm and 31% for 3mm scan diameters (p<0.021). In pseudophakic eyes, there also was an elevation of 3rd order RMS, on average 57% for 5mm and 51% for 3mm scan diameters (p<0.031). Conclusion Higher order wavefront aberrations in eyes with macular disease were greater than in control eyes without disease. Our study suggests that such aberrations may result from irregular or multiple reflecting retinal surfaces. Modifications in wavefront sensor technology will be needed to accurately determine wavefront aberration and allow correction using adaptive optics in eyes with macular irregularities. PMID:19574950

  4. Optic Nerve Imaging

    MedlinePlus

    ... About Us Donate In This Section Optic Nerve Imaging email Send this article to a friend by ... may use one of these optic nerve computer imaging techniques as part of your glaucoma examination. By ...

  5. Nerve Injuries in Gynecologic Laparoscopy.

    PubMed

    Abdalmageed, Osama S; Bedaiwy, Mohamed A; Falcone, Tommaso

    2017-01-01

    Nerve injuries during gynecologic endoscopy are an infrequent but distressing complication. In benign gynecologic surgery, most of these injuries are associated with patient positioning, although some are related to port placement. Most are potentially preventable with attention to patient placement on the operating room bed and knowledge of the relative anatomy of the nerves. The highest risk group vulnerable to these injuries includes women who have extreme body mass index and those with longer surgical times in the Trendelenburg position. Upper and lower limb peripheral nerves are the most common nerves injured during gynecologic endoscopy. These injuries can result in transient or permanent sensory and motor disabilities that can interrupt patient recovery in an otherwise successful surgery. Numerous strategies are suggested to reduce the frequency of nerve injuries during gynecologic endoscopies. Proper patient positioning and proper padding of the pressure areas are mandatory to prevent malposition-related nerve injuries. Anatomic knowledge of the course of nerves, especially ilioinguinal and iliohypogastric, nerves can minimize injury. Copyright © 2016 AAGL. Published by Elsevier Inc. All rights reserved.

  6. Interocular high-order corneal wavefront aberration symmetry

    NASA Astrophysics Data System (ADS)

    Lombardo, Marco; Lombardo, Giuseppe; Serrao, Sebastiano

    2006-04-01

    The interocular symmetry of the high-order corneal wavefront aberration (WA) in a population of myopic eyes was analyzed before and after photorefractive keratectomy (PRK). The preoperative and one-year postoperative corneal aberration data (from third to seventh Zernike orders) for 4- and 7-mm pupils from right and left eyes were averaged after correcting for the effects of enantiomorphism to test for mirror symmetry. Also, the mean corneal point-spread function (PSF) for right and left eyes was calculated. Preoperatively, a moderate and high degree of correlation in the high-order corneal WA between eyes was found for 4- and 7-mm pupils, respectively. Myopic PRK did not significantly change the interocular symmetry of corneal high-order aberrations. No discernible differences in the orientation PSF between eyes were observed one year after surgery in comparison with the preoperative state over the two analyzed pupils.

  7. Lethality of radiation-induced chromosome aberrations in human tumour cell lines with different radiosensitivities.

    PubMed

    Coco-Martin, J M; Ottenheim, C P; Bartelink, H; Begg, A C

    1996-03-01

    In order to find an explanation for the eventual disappearance of all chromosome aberrations in two radiosensitive human tumour cell lines, the type and stability of different aberration types was investigated in more detail. To classify the aberrations into unstable and stable types, three-colour fluorescence in situ hybridization was performed, including a whole-chromosome probe, a pancentromere probe, and a stain for total DNA. This technique enables the appropriate classification of the aberrations principally by the presence (stable) or not (unstable) of a single centromere per chromosome. Unstable-type aberrations were found to disappear within 7 days (several divisions) in the two radiosensitive and the two radioresistant tumour lines investigated. Stable-type aberrations were found to remain at an approximately constant level over the duration of the experiment (14 days; 8-10 divisions) in the two radioresistant lines. In contrast, the majority of these stable-type aberrations had disappeared by 14 days in the two radiosensitive lines. The previous findings of disappearance of total aberrations in radiosensitive cells was therefore not due to a reduced induction of stable-type aberrations, but the complete disappearance of cells with this aberration type. These results could not be explained by differences in apoptosis or G1 blocks. Two possible explanations for these unexpected findings involve non-random induction of unstable-type aberrations, or lethality of stable-type aberrations. The results suggest caution in the use of stable-type aberration numbers as a predictor for radiosensitivity.

  8. The aberration characteristics in a misaligned three-mirror anastigmatic (TMA) system

    NASA Astrophysics Data System (ADS)

    Wang, Bin; Wu, Fan; Ye, Yutang

    2016-09-01

    To realize the efficient alignment of the TMA system, the aberrations in a misaligned TMA system had been analyzed theoretically in this paper. Firstly, based on the nodal aberration theory (NAT), the aberration types and characteristics in the misaligned TMA system had been concluded; Secondly, a simulation validation had been carried out to testify the analysis results, the simulation results validates the aberration characteristics; Finally, the alignment procedures were determined according to the aberration characteristics: adjust the axial spacing of the mirrors in terms of Z9 in the center field of TMA system first; and then, adjust the decenters and tilts of the mirrors in terms of Z5 - Z8 in the edge field of TMA system. This method is helpful for the alignment of the TMA telescope.

  9. Influence of coma aberration on aperture averaged scintillations in oceanic turbulence

    NASA Astrophysics Data System (ADS)

    Luo, Yujuan; Ji, Xiaoling; Yu, Hong

    2018-01-01

    The influence of coma aberration on aperture averaged scintillations in oceanic turbulence is studied in detail by using the numerical simulation method. In general, in weak oceanic turbulence, the aperture averaged scintillation can be effectively suppressed by means of the coma aberration, and the aperture averaged scintillation decreases as the coma aberration coefficient increases. However, in moderate and strong oceanic turbulence the influence of coma aberration on aperture averaged scintillations can be ignored. In addition, the aperture averaged scintillation dominated by salinity-induced turbulence is larger than that dominated by temperature-induced turbulence. In particular, it is shown that for coma-aberrated Gaussian beams, the behavior of aperture averaged scintillation index is quite different from the behavior of point scintillation index, and the aperture averaged scintillation index is more suitable for characterizing scintillations in practice.

  10. Neuromuscular ultrasound of cranial nerves.

    PubMed

    Tawfik, Eman A; Walker, Francis O; Cartwright, Michael S

    2015-04-01

    Ultrasound of cranial nerves is a novel subdomain of neuromuscular ultrasound (NMUS) which may provide additional value in the assessment of cranial nerves in different neuromuscular disorders. Whilst NMUS of peripheral nerves has been studied, NMUS of cranial nerves is considered in its initial stage of research, thus, there is a need to summarize the research results achieved to date. Detailed scanning protocols, which assist in mastery of the techniques, are briefly mentioned in the few reference textbooks available in the field. This review article focuses on ultrasound scanning techniques of the 4 accessible cranial nerves: optic, facial, vagus and spinal accessory nerves. The relevant literatures and potential future applications are discussed.

  11. Drug Distribution into Peripheral Nerve.

    PubMed

    Liu, Houfu; Chen, Yan; Huang, Liang; Sun, Xueying; Fu, Tingting; Wu, Shengqian; Zhu, Xiaoyan; Zhen, Wei; Liu, Jihong; Lu, Gang; Cai, Wei; Yang, Ting; Zhang, Wandong; Yu, Xiaohong; Wan, Zehong; Wang, Jianfei; Summerfield, Scott G; Dong, Kelly; Terstappen, Georg C

    2018-05-01

    Little is known about the impact of the blood-nerve barrier (BNB) on drug distribution into peripheral nerves. In this study, we examined the peripheral nerve penetration in rats of 11 small-molecule drugs possessing diverse physicochemical and transport properties and ProTx-II, a tarantula venom peptide with molecular mass of 3826 Daltons. Each drug was administered as constant rate intravenous infusion for 6 hours (small molecules) or 24 hours (ProTx-II). Blood and tissues including brain, spinal cord, sciatic nerve, and dorsal root ganglion (DRG) were collected for drug concentration measurements. Unbound fractions of a set of compounds were determined by equilibrium dialysis method in rat blood, brains, spinal cords, sciatic nerves, and DRG. We also investigated the influence of N -[4-[2-(6,7-dimethoxy-3,4-dihydro-1 H -isoquinolin-2-yl)ethyl]phenyl]-5-methoxy-9-oxo-10 H -acridine-4-carboxamide (GF120918), a P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) inhibitor, on the peripheral nerve and central nervous system (CNS) tissue penetration of imatinib. We found that: 1) the unbound fraction in brain tissue homogenate highly correlates with that in the spinal cord, sciatic nerve, and DRG for a set of compounds and thus provides a good surrogate for spinal cord and peripheral nerve tissues, 2) small-molecule drugs investigated can penetrate the DRG and sciatic nerve, 3) P-gp and BCRP have a limited impact on the distribution of small-molecule drugs into peripheral nerves, and 4) DRG is permeable to ProTx-II, but its distribution into sciatic nerve and CNS tissues is restricted. These results demonstrate that small-molecule drugs investigated can penetrate peripheral nerve tissues, and P-gp/BCRP may not be a limiting factor at the BNB. Biologics as large as ProTx-II can access the DRG but not sciatic nerve and CNS tissues. Copyright © 2018 by The American Society for Pharmacology and Experimental Therapeutics.

  12. miRNA Expression Change in Dorsal Root Ganglia After Peripheral Nerve Injury.

    PubMed

    Chang, Hsueh-Ling; Wang, Hung-Chen; Chunag, Yi-Ta; Chou, Chao-Wen; Lin, I-Ling; Lai, Chung-Sheng; Chang, Lin-Li; Cheng, Kuang-I

    2017-02-01

    The role of microRNAs (miRNAs) in the regulation of nerve injury-induced neuropathic pain is unclear. The aims of this study were to assess and compare miRNA expression profiles in dorsal root ganglia (DRG) following three different kinds of peripheral nerve injury, including spinal nerve ligation (SNL), dorsal root transection (DRT), and ventral root transection (VRT), in Sprague-Dawley rats. Responses to thermal and mechanical stimuli were measured preoperatively and on postoperative days (PODs) 1, 4, and 7. A miRNA microarray analysis was used to detect the miRNA expression profiles in injured L5 DRG from SNL, DRT, and VRT on POD 7. Validation of miRNA expression was performed by qPCR and in situ hybridization. Rats receiving SNL displayed significantly higher mechanical hypersensitivity, but those receiving DRT developed higher thermal hypersensitivity. The number of miRNAs that were significantly upregulated in L5 DRG was 49 (7.2%), 25 (3.7%), and 146 (21.5%) following SNL, DRT, and VRT, respectively. On the other hand, 35 (5.1%) miRNAs were significantly downregulated in the SNL group, 21 (3.1%) miRNAs in the DRT group, and 41 (6.0%) miRNAs in the VRT group. Of the four miRNAs that were mutually aberrant in all three models, two were significantly upregulated (twofold), miR-21 and miR-31, and two were significantly downregulated, miR-668 and miR-672. Using in situ hybridization, miRNA-21, miRNA-31, miRNA-668, and miRNA-672 were found to localize to neurons in the DRG. Collectively, the mutual abnormal miRNA expression of miR-21, miR-31, miR-668, and miR-677 implied that these miRNAs may be therapeutic targets for alleviating multiple forms of neuropathic pain.

  13. Diagnostic value of the near-nerve needle sensory nerve conduction in sensory inflammatory demyelinating polyneuropathy.

    PubMed

    Odabasi, Zeki; Oh, Shin J

    2018-03-01

    In this study we report the diagnostic value of the near-nerve needle sensory nerve conduction study (NNN-SNCS) in sensory inflammatory demyelinating polyneuropathy (IDP) in which the routine nerve conduction study was normal or non-diagnostic. The NNN-SNCS was performed to identify demyelination in the plantar nerves in 14 patients and in the median or ulnar nerve in 2 patients with sensory IDP. In 16 patients with sensory IDP, routine NCSs were either normal or non-diagnostic for demyelination. Demyelination was identified by NNN-SNCS by dispersion and/or slow nerve conduction velocity (NCV) below the demyelination marker. Immunotherapy was initiated in 11 patients, 10 of whom improved or remained stable. NNN-SNCS played an essential role in identifying demyelinaton in 16 patients with sensory IDP, leading to proper treatment. Muscle Nerve 57: 414-418, 2018. © 2017 Wiley Periodicals, Inc.

  14. Interfascicular suture with nerve autografts for median, ulnar and radial nerve lesions.

    PubMed

    Pluchino, F; Luccarelli, G

    1981-05-01

    Interfascicular nerve suture with autografts is the operation of choice for repairing peripheral nerve injuries because it ensures more precise alignment of the fasciculi and so better chances of reinnervation of the sectioned nerve. The procedure as described by Millesi et al has been used at the Istituto Neurologico di Milano in 30 patients with traumatic lesions of the median, ulnar and radial nerves. All have been followed up for 2 to 7 years since operation. The results obtained are compared with those of other series obtained with interfascicular suture and with epineural suture. Microsurgery is essential. The best time to operate is discussed.

  15. Corneal Aberrations in Former Preterm Infants: Results From The Wiesbaden Prematurity Study.

    PubMed

    Fieß, Achim; Schuster, Alexander K; Kölb-Keerl, Ruth; Knuf, Markus; Kirchhof, Bernd; Muether, Philipp S; Bauer, Jacqueline

    2017-12-01

    To compare corneal aberrations in former preterm infants to that of full-term infants. A prospective cross-sectional study was carried out measuring the corneal shape with Scheimpflug imaging in former preterm infants of gestational age (GA) ≤32 weeks and full-term infants with GA ≥37 weeks now being aged between 4 to 10 years. The main outcome measures were corneal aberrations including astigmatism (Zernike: Z2-2; Z22), coma (Z3-1; Z31), trefoil (Z3-3; Z33), spherical aberration (Z40) and root-mean square of higher-order aberrations (RMS HOA). Multivariable analysis was performed to assess independent associations of gestational age groups and of retinopathy of prematurity (ROP) occurrence with corneal aberrations adjusting for sex and age at examination. A total of 259 former full-term and 226 preterm infants with a mean age of 7.2 ± 2.0 years were included in this study. Statistical analysis revealed an association of extreme prematurity (GA ≤28 weeks) with higher-order and lower-order aberrations of the total cornea. Vertical coma was higher in extreme prematurity (P < 0.001), due to the shape of the anterior corneal surface, while there was no association with trefoil and spherical aberration. ROP was not associated with higher-order aberrations when adjusted for gestational age group. This study demonstrated that specific corneal aberrations were associated with extreme prematurity rather than with ROP occurrence.

  16. Effect of Surface Pore Structure of Nerve Guide Conduit on Peripheral Nerve Regeneration

    PubMed Central

    Oh, Se Heang; Kim, Jin Rae; Kwon, Gu Birm; Namgung, Uk; Song, Kyu Sang

    2013-01-01

    Polycaprolactone (PCL)/Pluronic F127 nerve guide conduits (NGCs) with different surface pore structures (nano-porous inner surface vs. micro-porous inner surface) but similar physical and chemical properties were fabricated by rolling the opposite side of asymmetrically porous PCL/F127 membranes. The effect of the pore structure on peripheral nerve regeneration through the NGCs was investigated using a sciatic nerve defect model of rats. The nerve fibers and tissues were shown to have regenerated along the longitudinal direction through the NGC with a nano-porous inner surface (Nanopore NGC), while they grew toward the porous wall of the NGC with a micro-porous inner surface (Micropore NGC) and, thus, their growth was restricted when compared with the Nanopore NGC, as investigated by immunohistochemical evaluations (by fluorescence microscopy with anti-neurofilament staining and Hoechst staining for growth pattern of nerve fibers), histological evaluations (by light microscopy with Meyer's modified trichrome staining and Toluidine blue staining and transmission electron microscopy for the regeneration of axon and myelin sheath), and FluoroGold retrograde tracing (for reconnection between proximal and distal stumps). The effect of nerve growth factor (NGF) immobilized on the pore surfaces of the NGCs on nerve regeneration was not so significant when compared with NGCs not containing immobilized NGF. The NGC system with different surface pore structures but the same chemical/physical properties seems to be a good tool that is used for elucidating the surface pore effect of NGCs on nerve regeneration. PMID:22871377

  17. Anatomy of pudendal nerve at urogenital diaphragm--new critical site for nerve entrapment.

    PubMed

    Hruby, Stephan; Ebmer, Johannes; Dellon, A Lee; Aszmann, Oskar C

    2005-11-01

    To investigate the relations of the pudendal nerve in this complex anatomic region and determine possible entrapment sites that are accessible for surgical decompression. Entrapment neuropathies of the pudendal nerve are an uncommon and, therefore, often overlooked or misdiagnosed clinical entity. The detailed relations of this nerve as it exits the pelvis through the urogenital diaphragm and enters the mobile part of the penis have not yet been studied. Detailed anatomic dissections were performed in 10 formalin preserved hemipelves under 3.5x loupe magnification. The pudendal nerve was dissected from the entrance into the Alcock canal to the dorsum of the penis. The branching pattern of the nerve and its topographic relationship were recorded and photographs taken. The anatomic dissections revealed that the pudendal nerve passes through a tight osteofibrotic canal just distal to the urogenital diaphragm at the entrance to the base of the penis. This canal is, in part, formed by the inferior ramus of the pubic bone, the suspensory ligament of the penis, and the ischiocavernous body. In two specimens, a fusiform pseudoneuromatous thickening was found. The pudendal nerve is susceptible to compression at the passage from the Alcock canal to the dorsum of the penis. Individuals exposed to repetitive mechanical irritation in this region are especially endangered. Diabetic patients with peripheral neuropathy can have additional compression neuropathy with decreased penile sensibility and will benefit from decompression of the pudendal nerve.

  18. Delayed repair of the peripheral nerve: a novel model in the rat sciatic nerve.

    PubMed

    Wu, Peng; Spinner, Robert J; Gu, Yudong; Yaszemski, Michael J; Windebank, Anthony J; Wang, Huan

    2013-03-30

    Peripheral nerve reconstruction is seldom done in the acute phase of nerve injury due to concomitant injuries and the uncertainty of the extent of nerve damage. A proper model that mimics true clinical scenarios is critical but lacking. The aim of this study is to develop a standardized, delayed sciatic nerve repair model in rats and validate the feasibility of direct secondary neurrorraphy after various delay intervals. Immediately or 1, 4, 6, 8 and 12 weeks after sciatic nerve transection, nerve repair was carried out. A successful tension-free direct neurorraphy (TFDN) was defined when the gap was shorter than 4.0 mm and the stumps could be reapproximated with 10-0 stitches without detachment. Compound muscle action potential (CMAP) was recorded postoperatively. Gaps between the two nerve stumps ranged from 0 to 9 mm, the average being 1.36, 2.85, 3.43, 3.83 and 6.4 mm in rats with 1, 4, 6, 8 and 12 week delay, respectively. The rate of successful TFDN was 78% overall. CMAP values of 1 and 4 week delay groups were not different from the immediate repair group, whereas CMAP amplitudes of 6, 8 and 12 week delay groups were significantly lower. A novel, standardized delayed nerve repair model is established. For this model to be sensitive, the interval between nerve injury and secondary repair should be at least over 4 weeks. Thereafter the longer the delay, the more challenging the model is for nerve regeneration. The choice of delay intervals can be tailored to meet specific requirements in future studies. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Detecting Aberrant Response Patterns in the Rasch Model. Rapport 87-3.

    ERIC Educational Resources Information Center

    Kogut, Jan

    In this paper, the detection of response patterns aberrant from the Rasch model is considered. For this purpose, a new person fit index, recently developed by I. W. Molenaar (1987) and an iterative estimation procedure are used in a simulation study of Rasch model data mixed with aberrant data. Three kinds of aberrant response behavior are…

  20. "Long-term stability of stimulating spiral nerve cuff electrodes on human peripheral nerves".

    PubMed

    Christie, Breanne P; Freeberg, Max; Memberg, William D; Pinault, Gilles J C; Hoyen, Harry A; Tyler, Dustin J; Triolo, Ronald J

    2017-07-11

    Electrical stimulation of the peripheral nerves has been shown to be effective in restoring sensory and motor functions in the lower and upper extremities. This neural stimulation can be applied via non-penetrating spiral nerve cuff electrodes, though minimal information has been published regarding their long-term performance for multiple years after implantation. Since 2005, 14 human volunteers with cervical or thoracic spinal cord injuries, or upper limb amputation, were chronically implanted with a total of 50 spiral nerve cuff electrodes on 10 different nerves (mean time post-implant 6.7 ± 3.1 years). The primary outcome measures utilized in this study were muscle recruitment curves, charge thresholds, and percent overlap of recruited motor unit populations. In the eight recipients still actively involved in research studies, 44/45 of the spiral contacts were still functional. In four participants regularly studied over the course of 1 month to 10.4 years, the charge thresholds of the majority of individual contacts remained stable over time. The four participants with spiral cuffs on their femoral nerves were all able to generate sufficient moment to keep the knees locked during standing after 2-4.5 years. The dorsiflexion moment produced by all four fibular nerve cuffs in the active participants exceeded the value required to prevent foot drop, but no tibial nerve cuffs were able to meet the plantarflexion moment that occurs during push-off at a normal walking speed. The selectivity of two multi-contact spiral cuffs was examined and both were still highly selective for different motor unit populations for up to 6.3 years after implantation. The spiral nerve cuffs examined remain functional in motor and sensory neuroprostheses for 2-11 years after implantation. They exhibit stable charge thresholds, clinically relevant recruitment properties, and functional muscle selectivity. Non-penetrating spiral nerve cuff electrodes appear to be a suitable option

  1. Quality factor analysis for aberrated laser beam

    NASA Astrophysics Data System (ADS)

    Ghafary, B.; Alavynejad, M.; Kashani, F. D.

    2006-12-01

    The quality factor of laser beams has attracted considerable attention and some different approaches have been reported to treat the problem. In this paper we analyze quality factor of laser beam and compare the effect of different aberrations on beam quality by expanding pure phase term of wavefront in terms of Zernike polynomials. Also we analyze experimentally the change of beam quality for different Astigmatism aberrations, and compare theoretical results with experimentally results. The experimental and theoretical results are in good agreement.

  2. Axillary nerve dysfunction

    MedlinePlus

    ... Causes Axillary nerve dysfunction is a form of peripheral neuropathy . It occurs when there is damage to the ... and the A.D.A.M. Editorial team. Peripheral Nerve Disorders Read more NIH MedlinePlus Magazine Read more Health ...

  3. Optical aberrations measurement with a low cost optometric instrument

    NASA Astrophysics Data System (ADS)

    Furlan, Walter D.; Muñoz-Escrivá, L.; Pons, A.; Martínez-Corral, M.

    2002-08-01

    A simple experimental method for measuring optical aberrations of a single lens is proposed. The technique is based on the use of an optometric instrument employed for the assessment of the refractive state of the eye: the retinoscope. Experimental results for spherical aberration and astigmatism are obtained.

  4. Analysis of nodal aberration properties in off-axis freeform system design.

    PubMed

    Shi, Haodong; Jiang, Huilin; Zhang, Xin; Wang, Chao; Liu, Tao

    2016-08-20

    Freeform surfaces have the advantage of balancing off-axis aberration. In this paper, based on the framework of nodal aberration theory (NAT) applied to the coaxial system, the third-order astigmatism and coma wave aberration expressions of an off-axis system with Zernike polynomial surfaces are derived. The relationship between the off-axis and surface shape acting on the nodal distributions is revealed. The nodal aberration properties of the off-axis freeform system are analyzed and validated by using full-field displays (FFDs). It has been demonstrated that adding Zernike terms, up to nine, to the off-axis system modifies the nodal locations, but the field dependence of the third-order aberration does not change. On this basis, an off-axis two-mirror freeform system with 500 mm effective focal length (EFL) and 300 mm entrance pupil diameter (EPD) working in long-wave infrared is designed. The field constant aberrations induced by surface tilting are corrected by selecting specific Zernike terms. The design results show that the nodes of third-order astigmatism and coma move back into the field of view (FOV). The modulation transfer function (MTF) curves are above 0.4 at 20 line pairs per millimeter (lp/mm) which meets the infrared reconnaissance requirement. This work provides essential insight and guidance for aberration correction in off-axis freeform system design.

  5. Effects of ocular aberrations on contrast detection in noise.

    PubMed

    Liang, Bo; Liu, Rong; Dai, Yun; Zhou, Jiawei; Zhou, Yifeng; Zhang, Yudong

    2012-08-06

    We use adaptive optics (AO) techniques to manipulate the ocular aberrations and elucidate the effects of these ocular aberrations on contrast detection in a noisy background. The detectability of sine wave gratings at frequencies of 4, 8, and 16 circles per degree (cpd) was measured in a standard two-interval force-choice staircase procedure against backgrounds of various levels of white noise. The observer's ocular aberrations were either corrected with AO or left uncorrected. In low levels of external noise, contrast detection thresholds are always lowered by AO correction, whereas in high levels of external noise, they are generally elevated by AO correction. Higher levels of external noise are required to make this threshold elevation observable when signal spatial frequencies increase from 4 to 16 cpd. The linear-amplifier-model fit shows that mostly sampling efficiency and equivalent noise both decrease with AO correction. Our findings indicate that ocular aberrations could be beneficial for contrast detection in high-level noises. The implications of these findings are discussed.

  6. Design for an aberration corrected scanning electron microscope using miniature electron mirrors.

    PubMed

    Dohi, Hideto; Kruit, Pieter

    2018-06-01

    Resolution of scanning electron microscopes (SEMs) is determined by aberrations of the objective lens. It is well known that both spherical and chromatic aberrations can be compensated by placing a 90-degree bending magnet and an electron mirror in the beam path before the objective lens. Nevertheless, this approach has not led to wide use of these aberration correctors, partly because aberrations of the bending magnet can be a serious problem. A mirror corrector with two mirrors placed perpendicularly to the optic axis of an SEM and facing each other is proposed. As a result, only small-angle magnetic deflection is necessary to guide the electron beam around the top mirror to the bottom mirror and around the bottom mirror to the objective lens. The deflection angle, in the order of 50 mrad, is sufficiently small to avoid deflection aberrations. In addition, lateral dispersion at the sample plane can be avoided by making the deflection fields symmetric. Such a corrector system is only possible if the incoming beam can pass the top mirror at a distance in the order of millimeters, without being disturbed by the electric fields of electrodes of the mirror. It is proposed that condition can be satisfied with micro-scale electron optical elements fabricated by using MEMS technology. In the proposed corrector system, the micro-mirrors have to provide the exact negative spherical and chromatic aberrations for correcting the aberration of the objective lens. This exact tuning is accomplished by variable magnification between the micro-mirrors and the objective lens using an additional transfer lens. Extensive optical calculations are reported. Aberrations of the micro-mirrors were analyzed by numerical calculation. Dispersion and aberrations of the deflectors were calculated by using an analytical field model. Combination aberrations caused by the off-axis position of dispersive rays in the mirrors and objective lens were also analyzed. It is concluded that the proposed

  7. Sources of the monochromatic aberrations induced in human eyes after laser refractive surgery

    NASA Astrophysics Data System (ADS)

    Porter, Jason

    Laser in-situ keratomileusis (LASIK) procedures correct the eye's defocus and astigmatism but also introduce higher order monochromatic aberrations. Little is known about the origins of these induced aberrations. The advent of wavefront sensor technology has made it possible to measure accurately and quickly the aberrations of normal and postoperative LASIK eyes. The goal of this thesis was to exploit this technology to better understand some of the potential mechanisms by which aberrations could be introduced during LASIK. A first step towards investigating these sources was to characterize the aberration changes in post-LASIK eyes. Higher order rms wavefront error increased after conventional and customized LASIK surgery. On average, spherical aberration approximately doubled, and significant changes in vertical and horizontal coma were observed. We examined two sources of postoperative aberrations: the creation of a microkeratome flap and the subsequent laser ablation. Higher order rms increased slightly and there was a wide variation in the response of individual Zernike modes after cutting a flap. The majority of induced spherical aberration was due to the laser ablation and not the flap-cut. Aberrations are also induced by static and dynamic decentrations of the patient's pupil. We found that ablations were typically decentered in the superotemporal direction due to shifts in pupil center location between aberration measurement (dilated) and surgical (undilated) conditions in customized LASIK eyes. There was a weak correlation between the horizontal coma theoretically induced by this offset and that measured postoperatively. Finally, dynamic eye movements during the procedure induce higher order aberrations. We found that the most problematic decentrations during LASIK are relatively slow drifts in eye position. An eye-tracking system with a 2-Hz closed-loop bandwidth could compensate for most eye movements during LASIK. One solution for reducing the

  8. Large Extremity Peripheral Nerve Repair

    DTIC Science & Technology

    2013-10-01

    can provide fixation strengths approaching that of conventional microsurgery and that the PTB repair is unlikely to be disturbed in vivo. The...of nerve wrap biomaterial during long periods of recovery associated with large nerve deficit reconstruction and long nerve grafts. As with the...PTB/xHAM wrap compared to standard (suture) of care microsurgery . Demonstrated improved nerve regeneration in a muscle mass retention model

  9. Large Extremity Peripheral Nerve Repair

    DTIC Science & Technology

    2013-10-01

    show that the PTB method can provide fixation strengths approaching that of conventional microsurgery and that the PTB repair is unlikely to be...biomaterial during long periods of recovery associated with large nerve deficit reconstruction and long nerve grafts. As with the human amnion nerve...functional recovery model (SFI, sciatic function index) using PTB/xHAM wrap compared to standard (suture) of care microsurgery . Demonstrated improved nerve

  10. Fate of combat nerve injury.

    PubMed

    Beltran, Michael J; Burns, Travis C; Eckel, Tobin T; Potter, Benjamin K; Wenke, Joseph C; Hsu, Joseph R

    2012-11-01

    Assess a cohort of combat-related type III open tibia fractures with peripheral nerve injury to determine the injury mechanism and likelihood for recovery or improvement in nerve function. Retrospective study. Three military medical centers. Out of a study cohort of 213 type III open tibia fractures, 32 fractures (in 32 patients) with a total of 43 peripheral nerve injuries (peroneal or tibial) distal to the popliteal fossa met inclusion criteria and were available for follow-up at an average of 20 months (range, 2-48 months). Clinical assessment of motor and sensory nerve improvement. There was a 22% incidence of peripheral nerve injury in the study cohort. At an average follow-up of 20 months (range, 2-48 months), 89% of injured motor nerves were functional, whereas the injured sensory nerves had function in 93%. Fifty percent and 27% of motor and sensory injuries demonstrated improvement, respectively (P = 0.043). With the numbers available, there was no difference in motor or sensory improvement based on mechanism of injury, fracture severity or location, soft tissue injury, or specific nerve injured. In the subset of patients with an initially impaired sensory examination, full improvement was related to fracture location (P = 0.0164). Type III open tibia fractures sustained in combat are associated with a 22% incidence of peripheral nerve injury, and the majority are due to multiple projectile penetrating injury. Despite the severe nature of these injuries, the vast majority of patients had a functional nerve status by an average of 2-year follow-up. Based on these findings, discussions regarding limb salvage and amputation should not be overly influenced by the patient's peripheral nerve status. Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

  11. Variability of higher order wavefront aberrations after blinks.

    PubMed

    Hagyó, Krisztina; Csákány, Béla; Lang, Zsolt; Németh, János

    2009-01-01

    To investigate the rapid alterations in value and fluctuation of ocular wavefront aberrations during the interblink interval. Forty-two volunteers were examined with a WASCA Wavefront Analyzer (Carl Zeiss Meditec AG) using modified software. For each subject, 150 images (about 6 frames/second) were registered during an interblink period. The outcome measures were spherical and cylindrical refraction and root-mean-square (RMS) values for spherical, coma, and total higher order aberrations. Fifth order polynomials were fitted to the data and the fluctuation trends of the parameters were determined. We calculated the prevalence of the trends with an early local minimum (type 1). The tear production status (Schirmer test) and tear film break-up time (BUT) were also measured. Fluctuation trends with an early minimum (type 1) were significantly more frequent than trends with an early local maximum (type 2) for total higher order aberrations RMS (P=.036). The incidence of type 1 fluctuation trends was significantly greater for coma and total higher order aberrations RMS (P=.041 and P=.003, respectively) in subjects with normal results in the BUT or Schirmer test than in those with abnormal results. In the normal subjects, the first minimum of type 1 RMS fluctuation trends occurred, on average, between 3.8 and 5.1 seconds after blink. We suggest that wavefront aberrations can be measured most accurately at the time after blink when they exhibit a decreased degree of dispersion. We recommend that a snapshot of wavefront measurements be made 3 to 5 seconds after blink.

  12. Construction of special eye models for investigation of chromatic and higher-order aberrations of eyes.

    PubMed

    Zhai, Yi; Wang, Yan; Wang, Zhaoqi; Liu, Yongji; Zhang, Lin; He, Yuanqing; Chang, Shengjiang

    2014-01-01

    An achromatic element eliminating only longitudinal chromatic aberration (LCA) while maintaining transverse chromatic aberration (TCA) is established for the eye model, which involves the angle formed by the visual and optical axis. To investigate the impacts of higher-order aberrations on vision, the actual data of higher-order aberrations of human eyes with three typical levels are introduced into the eye model along visual axis. Moreover, three kinds of individual eye models are established to investigate the impacts of higher-order aberrations, chromatic aberration (LCA+TCA), LCA and TCA on vision under the photopic condition, respectively. Results show that for most human eyes, the impact of chromatic aberration on vision is much stronger than that of higher-order aberrations, and the impact of LCA in chromatic aberration dominates. The impact of TCA is approximately equal to that of normal level higher-order aberrations and it can be ignored when LCA exists.

  13. Aberrant alternative splicing is another hallmark of cancer.

    PubMed

    Ladomery, Michael

    2013-01-01

    The vast majority of human genes are alternatively spliced. Not surprisingly, aberrant alternative splicing is increasingly linked to cancer. Splice isoforms often encode proteins that have distinct and even antagonistic properties. The abnormal expression of splice factors and splice factor kinases in cancer changes the alternative splicing of critically important pre-mRNAs. Aberrant alternative splicing should be added to the growing list of cancer hallmarks.

  14. Bladder Control and Nerve Disease

    MedlinePlus

    ... VUR) The Urinary Tract & How It Works Bladder Control Problems & Nerve Disease For the urinary system to ... the bladder do not work properly. What bladder control problems does nerve damage cause? Nerves that work ...

  15. Nerve stimulator-guided sciatic-femoral nerve block in raptors undergoing surgical treatment of pododermatitis.

    PubMed

    d'Ovidio, Dario; Noviello, Emilio; Adami, Chiara

    2015-07-01

    To describe the nerve stimulator-guided sciatic-femoral nerve block in raptors undergoing surgical treatment of pododermatitis. Prospective clinical trial. Five captive raptors (Falco peregrinus) aged 6.7 ± 1.3 years. Anaesthesia was induced and maintained with isoflurane in oxygen. The sciatic-femoral nerve block was performed with 2% lidocaine (0.05 mL kg(-1) per nerve) as the sole intra-operative analgesic treatment. Intraoperative physiological variables were recorded every 10 minutes from endotracheal intubation until the end of anaesthesia. Assessment of intraoperative nociception was based on changes in physiological variables above baseline values, while evaluation of postoperative pain relied on species-specific behavioural indicators. The sciatic-femoral nerve block was feasible in raptors and the motor responses following electrical stimulation of both nerves were consistent with those reported in mammalian species. During surgery no rescue analgesia was required. The anaesthesia plane was stable and cardiorespiratory variables did not increase significantly in response to surgical stimulation. Iatrogenic complications, namely nerve damage and local anaesthetic toxicity, did not occur. Recovery was smooth and uneventful. The duration (mean ± SD) of the analgesic effect provided by the nerve block was 130 ± 20 minutes. The sciatic-femoral nerve block as described in dogs and rabbits can be performed in raptors as well. Further clinical trials with a control groups are required to better investigate the analgesic efficacy and the safety of this technique in raptors. © 2014 Association of Veterinary Anaesthetists and the American College of Veterinary Anesthesia and Analgesia.

  16. Spatially resolved wavefront aberrations of ophthalmic progressive-power lenses in normal viewing conditions.

    PubMed

    Villegas, Eloy A; Artal, Pablo

    2003-02-01

    To measure the wavefront aberration at different locations in progressive-power lenses (PPL's) isolated and in situ (PPL's plus eye). A Hartmann-Shack wavefront sensor was used to measure progressive-power lenses and human eyes either independently or in combination. In each selected zone, the lens was placed and tilted accordingly to simulate natural viewing conditions. We measured 21 relevant locations across an isolated PPL (plano lens of power addition of 2 D). In six of the locations, the wavefront aberration of the eye plus PPL were obtained in two ways: (1) by direct measurement of the system and (2) by adding the individual wavefront aberrations of the eye and the lens for each appropriate zone. In every case, we obtained the wavefront aberration as Zernike polynomials expansions, the root mean square error, the point-spread function, and the Strehl ratio. Along the corridor of the PPL, third-order coma and trefoil, and astigmatism were the dominant aberrations. In areas of the PPL outside the corridor, astigmatism increased, whereas other aberrations remained similar to the lens center. Small differences were found between the direct and calculated methods used to obtain the wavefront aberration of the eye with the lens, and the possible sources of errors were discussed. In some lenses zones, the aberrations of the lens may be compensated by the particular aberrations of the eye, yielding improved optical performance over that present in the lens alone. We designed and built a wavefront sensor to perform spatially resolved aberration measurements in ophthalmic lenses, in particular in PPL's, either isolated or in combination with the eye. The aberrations appearing in the PPL were compared with those in normal aged eyes.

  17. Evaluation of phrenic nerve and diaphragm function with peripheral nerve stimulation and M-mode ultrasonography in potential pediatric phrenic nerve or diaphragm pacing candidates.

    PubMed

    Skalsky, Andrew J; Lesser, Daniel J; McDonald, Craig M

    2015-02-01

    Assessing phrenic nerve function in the setting of diaphragmatic paralysis in diaphragm pacing candidates can be challenging. Traditional imaging modalities and electrodiagnostic evaluations are technically difficult. Either modality alone is not a direct measure of the function of the phrenic nerve and diaphragm unit. In this article, the authors present their method for evaluating phrenic nerve function and the resulting diaphragm function. Stimulating the phrenic nerve with transcutaneous stimulation and directly observing the resulting movement of the hemidiaphragm with M-mode ultrasonography provides quantitative data for predicting the success of advancing technologies such as phrenic nerve pacing and diaphragm pacing. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Nanofocusing with aberration-corrected rotationally parabolic refractive X-ray lenses

    DOE PAGES

    Seiboth, Frank; Wittwer, Felix; Scholz, Maria; ...

    2018-01-01

    Wavefront errors of rotationally parabolic refractive X-ray lenses made of beryllium (Be CRLs) have been recovered for various lens sets and X-ray beam configurations. Due to manufacturing via an embossing process, aberrations of individual lenses within the investigated ensemble are very similar. By deriving a mean single-lens deformation for the ensemble, aberrations of any arbitrary lens stack can be predicted from the ensemble with σ¯ = 0.034λ. Using these findings the expected focusing performance of current Be CRLs are modeled for relevant X-ray energies and bandwidths and it is shown that a correction of aberrations can be realised without priormore » lens characterization but simply based on the derived lens deformation. As a result, the performance of aberration-corrected Be CRLs is discussed and the applicability of aberration-correction demonstrated over wide X-ray energy ranges.« less

  19. Large Extremity Peripheral Nerve Repair

    DTIC Science & Technology

    2013-10-01

    approaching that of conventional microsurgery and that the PTB repair is unlikely to be disturbed in vivo. The results in Figure 5 were obtained with...with large nerve deficit reconstruction and long nerve grafts. As with the human amnion nerve wraps, it was important for us to confirm that, in...xHAM wrap compared to standard (suture) of care microsurgery . Demonstrated improved nerve regeneration in a muscle mass retention model

  20. Trends in the design of nerve guidance channels in peripheral nerve tissue engineering.

    PubMed

    Chiono, Valeria; Tonda-Turo, Chiara

    2015-08-01

    The current trend of peripheral nerve tissue engineering is the design of advanced nerve guidance channels (NGCs) acting as physical guidance for regeneration of nerves across lesions. NGCs should present multifunctional properties aiming to direct the sprouting of axons from the proximal nerve end, to concentrate growth factors secreted by the injured nerve ends, and to reduce the ingrowth of scar tissue into the injury site. A critical aspect in the design of NGCs is conferring them the ability to provide topographic, chemotactic and haptotactic cues that lead to functional nerve regeneration thus increasing the axon growth rate and avoiding or minimizing end-organ (e.g. muscle) atrophy. The present work reviews the recent state of the art in NGCs engineering and defines the external guide and internal fillers structural and compositional requirements that should be satisfied to improve nerve regeneration, especially in the case of large gaps (>2 cm). Techniques for NGCs fabrication were described highlighting the innovative approaches direct to enhance the regeneration of axon stumps compared to current clinical treatments. Furthermore, the possibility to apply stem cells as internal cues to the NGCs was discussed focusing on scaffold properties necessary to ensure cell survival. Finally, the optimized features for NGCs design were summarized showing as multifunctional cues are needed to produce NGCs having improved results in clinics. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Facilitation of facial nerve regeneration using chitosan-β-glycerophosphate-nerve growth factor hydrogel.

    PubMed

    Chao, Xiuhua; Xu, Lei; Li, Jianfeng; Han, Yuechen; Li, Xiaofei; Mao, YanYan; Shang, Haiqiong; Fan, Zhaomin; Wang, Haibo

    2016-06-01

    Conclusion C/GP hydrogel was demonstrated to be an ideal drug delivery vehicle and scaffold in the vein conduit. Combined use autologous vein and NGF continuously delivered by C/GP-NGF hydrogel can improve the recovery of facial nerve defects. Objective This study investigated the effects of chitosan-β-glycerophosphate-nerve growth factor (C/GP-NGF) hydrogel combined with autologous vein conduit on the recovery of damaged facial nerve in a rat model. Methods A 5 mm gap in the buccal branch of a rat facial nerve was reconstructed with an autologous vein. Next, C/GP-NGF hydrogel was injected into the vein conduit. In negative control groups, NGF solution or phosphate-buffered saline (PBS) was injected into the vein conduits, respectively. Autologous implantation was used as a positive control group. Vibrissae movement, electrophysiological assessment, and morphological analysis of regenerated nerves were performed to assess nerve regeneration. Results NGF continuously released from C/GP-NGF hydrogel in vitro. The recovery rate of vibrissae movement and the compound muscle action potentials of regenerated facial nerve in the C/GP-NGF group were similar to those in the Auto group, and significantly better than those in the NGF group. Furthermore, larger regenerated axons and thicker myelin sheaths were obtained in the C/GP-NGF group than those in the NGF group.

  2. [Prenatal diagnostics of chromosomal aberrations Czech Republic: 1994-2007].

    PubMed

    Gregor, V; Sípek, A; Sípek, A; Horácek, J '; Langhammer, P; Petrzílková, L; Calda, P

    2009-02-01

    An analysis of prenatal diagnostics efficiency of selected types of chromosomal aberrations in the Czech Republic in 2007. Update of 1994-2007 data according to particular selected diagnoses. Retrospective epidemiological analysis of pre- and postnatal chromosomal aberrations diagnostics and its efficiency. Data on pre- and postnatally diagnosed birth defects in the Czech Republic during 1994-2007 were used. Data on prenatally diagnosed birth defects (and for terminated pregnancies) were collected from particular departments of prenatal diagnostics, medical genetics and ultrasound diagnostics in the Czech Republic, data on birth defects in births from the National Birth Defects Register (Institute for Health Information and Statistics). Total numbers over the period under the study, mean incidences of selected types of chromosomal aberrations and mean prenatal diagnostics efficiencies were analyzed. Following chromosomal aberrations were studied: Down, Edwards, Patau, Turner and Klinefelter syndromes and syndromes 47,XXX and 47,XYY. A relative proportion of Down, Edwards and Patau syndromes as well as other autosomal and gonosomal aberration is presented in figures. Recently, trisomies 13, 18 and 21 present around 70% of all chromosomal aberrations in selectively aborted fetuses, in other pregnancies, "other chromosomal aberrations" category (mostly balanced reciprocal translocations and inversions) present more than 2/3 of all diagnoses. During the period under the study, following total numbers, mean relative incidences (per 10,000 live births, in brackets) and mean prenatal diagnostics efficiency (in %) were found in following chromosomal syndromes: Down syndrome 2,244 (16.58) and 63.37%, Edwards syndrome 521 (3.85) and 79.93%, Patau syndrome 201 (1.49) and 68.87%, Turner syndrome 380 (2.81) and 79.89%, 47,XXX syndrome 61 (0.45) and 59.74%, Klinefelter syndrome 163 (1.20) and 73.65% and 47,XYY syndrome 22 (0.16) and 54.76%. The study gives updated results of

  3. Cellulose/soy protein composite-based nerve guidance conduits with designed microstructure for peripheral nerve regeneration

    NASA Astrophysics Data System (ADS)

    Gan, Li; Zhao, Lei; Zhao, Yanteng; Li, Ke; Tong, Zan; Yi, Li; Wang, Xiong; Li, Yinping; Tian, Weiqun; He, Xiaohua; Zhao, Min; Li, Yan; Chen, Yun

    2016-10-01

    Objective. The objective of this work was to develop nerve guidance conduits from natural polymers, cellulose and soy protein isolate (SPI), by evaluating the effects of cellulose/SPI film-based conduit (CSFC) and cellulose/SPI sponge-based conduit (CSSC) on regeneration of nerve defects in rats. Approach. CSFC and CSSC with the same chemical components were fabricated from cellulose and SPI. Effects of CSSC and CSFC on regeneration of the defective nerve were comparatively investigated in rats with a 10 mm long gap in sciatic nerve. The outcomes of peripheral nerve repair were evaluated by a combination of electrophysiological assessment, Fluoro-Gold retrograde tracing, double NF200/S100 immunofluorescence analysis, toluidine blue staining, and electron microscopy. The probable molecular mechanism was investigated using quantitative real-time PCR (qPCR) analysis. Main results. Compared with CSFC, CSSC had 2.69 times higher porosity and 5.07 times higher water absorption, thus ensuring much higher permeability. The nerve defects were successfully bridged and repaired by CSSC and CSFC. Three months after surgery, the CSSC group had a higher compound muscle action potential amplitude ratio, a higher percentage of positive NF200 and S100 staining, and a higher axon diameter and myelin sheath thickness than the CSFC group, showing the repair efficiency of CSSC was higher than that of CSFC. qPCR analysis indicated the mRNA levels of nerve growth factor, IL-10, IL-6, and growth-associated protein 43 (GAP-43) were higher in the CSSC group. This also indicated that there was better nerve repair with CSSC due to the higher porosity and permeability of CSSC providing a more favourable microenvironment for nerve regeneration than CSFC. Significance. A promising nerve guidance conduit was developed from cellulose/SPI sponge that showed potential for application in the repair of nerve defect. This work also suggests that nerve guidance conduits with better repair efficiency

  4. Length of nerve gap defects correlates with incidence of nerve regeneration but not with recovery of taste function in patients with severed chorda tympani nerve.

    PubMed

    Saito, Takehisa; Narita, Norihiko; Yamada, Takechiyo; Ogi, Kazuhiro; Kanno, Masafumi; Manabe, Yasuhiro; Ito, Tetsufumi

    2011-10-01

    To evaluate the relationship between the length of nerve gap defects, incidence of nerve regeneration, and recovery of gustatory function after severing the chorda tympani nerve (CTN). Retrospective study. University hospital. Eighty-eight consecutive patients whose CTNs were severed during primary surgery and who underwent secondary surgery were included. Proximal and distal stumps of severed nerves were readapted or approximated during surgery. Therapeutic. Before and after surgery, the taste function was periodically evaluated using electrogustometry. Nerve gaps were classified into 4 groups: readaptation (Group 1), 1 to 3 mm (Group 2), 4 to 6 mm (Group 3), and more than 7 mm (Group 4). Regenerated nerves in the tympanic segment were detected in 36 (41%) of the 88 patients during secondary surgery. The incidence of nerve regeneration was 100% (10/10) in Group 1, 45% (10/22) in Group 2, 47% (9/19) in Group 3, and 19% (7/37) in Group 4. There was a significant difference between the length of nerve gap defects and incidence of nerve regeneration (p < 0.001). In the 36 patients with a regenerated CTN, the incidence of gustatory function recovery was 60% (6/10) in Group 1, 50% (5/10) in Group 2, 56% (5/9) in Group 3, and 43% (3/7) in Group 4. There was no significant difference between the length of nerve gap defects and incidence of taste function recovery. Reconstruction of a severed CTN is very important for regeneration. However, the regenerated CTN in the tympanic segment does not always reinnervate the fungiform papillae.

  5. Effect of hip and knee position on nerve conduction in the common fibular nerve.

    PubMed

    Broadhurst, Peter Kaas; Robinson, Lawrence R

    2017-09-01

    The aim of this study was to measure the influence that hip and knee position have on routine fibular motor nerve conduction studies. Healthy subjects under age 40 were recruited (n = 24) to have fibular nerve conduction studies completed in various positions, using hip extension-knee extension as a control. A mean increase in conduction velocity of 2.5 m/s across the knee (P = 0.020) was seen during hip flexion compared with hip extension. A mean decrease in velocity of 1.6 m/s through the leg segment (P = 0.016) was seen during knee flexion compared with knee extension. This study shows that the optimal position of the leg during fibular nerve studies is with the hip in flexion and knee in extension, to more accurately reflect nerve length for velocity calculations. This may have implications for other peripheral nerves with respect to proximal joint position affecting calculated velocity. Muscle Nerve 56: 519-521, 2017. © 2017 Wiley Periodicals, Inc.

  6. New Theoretical Model of Nerve Conduction in Unmyelinated Nerves

    PubMed Central

    Akaishi, Tetsuya

    2017-01-01

    Nerve conduction in unmyelinated fibers has long been described based on the equivalent circuit model and cable theory. However, without the change in ionic concentration gradient across the membrane, there would be no generation or propagation of the action potential. Based on this concept, we employ a new conductive model focusing on the distribution of voltage-gated sodium ion channels and Coulomb force between electrolytes. Based on this new model, the propagation of the nerve conduction was suggested to take place far before the generation of action potential at each channel. We theoretically showed that propagation of action potential, which is enabled by the increasing Coulomb force produced by inflowing sodium ions, from one sodium ion channel to the next sodium channel would be inversely proportionate to the density of sodium channels on the axon membrane. Because the longitudinal number of sodium ion channel would be proportionate to the square root of channel density, the conduction velocity of unmyelinated nerves is theoretically shown to be proportionate to the square root of channel density. Also, from a viewpoint of equilibrium state of channel importation and degeneration, channel density was suggested to be proportionate to axonal diameter. Based on these simple basis, conduction velocity in unmyelinated nerves was theoretically shown to be proportionate to the square root of axonal diameter. This new model would also enable us to acquire more accurate and understandable vision on the phenomena in unmyelinated nerves in addition to the conventional electric circuit model and cable theory. PMID:29081751

  7. Adaptive Optics Analysis of Visual Benefit with Higher-order Aberrations Correction of Human Eye - Poster Paper

    NASA Astrophysics Data System (ADS)

    Xue, Lixia; Dai, Yun; Rao, Xuejun; Wang, Cheng; Hu, Yiyun; Liu, Qian; Jiang, Wenhan

    2008-01-01

    Higher-order aberrations correction can improve visual performance of human eye to some extent. To evaluate how much visual benefit can be obtained with higher-order aberrations correction we developed an adaptive optics vision simulator (AOVS). Dynamic real time optimized modal compensation was used to implement various customized higher-order ocular aberrations correction strategies. The experimental results indicate that higher-order aberrations correction can improve visual performance of human eye comparing with only lower-order aberration correction but the improvement degree and higher-order aberration correction strategy are different from each individual. Some subjects can acquire great visual benefit when higher-order aberrations were corrected but some subjects acquire little visual benefit even though all higher-order aberrations were corrected. Therefore, relative to general lower-order aberrations correction strategy, customized higher-order aberrations correction strategy is needed to obtain optimal visual improvement for each individual. AOVS provides an effective tool for higher-order ocular aberrations optometry for customized ocular aberrations correction.

  8. Human cytomegalovirus UL76 induces chromosome aberrations

    PubMed Central

    2009-01-01

    Background Human cytomegalovirus (HCMV) is known to induce chromosome aberrations in infected cells, which can lead to congenital abnormalities in infected fetuses. HCMV UL76 belongs to a conserved protein family from herpesviruses. Some reported roles among UL76 family members include involvement in virulence determination, lytic replication, reactivation of latent virus, modulation of gene expression, induction of apoptosis, and perturbation of cell cycle progression, as well as potential nuclease activity. Previously, we have shown that stable expression of UL76 inhibits HCMV replication in glioblastoma cells. Methods To examine chromosomal integrity and the DNA damage signal γ-H2AX in cells constitutively expressing UL76, immunofluorescent cell staining and Western blotting were performed. The comet assay was employed to assess DNA breaks in cells transiently expressing UL76. Results We report that stably transfected cells expressing UL76 developed chromosome aberrations including micronuclei and misaligned chromosomes, lagging and bridging. In mitotic cells expressing UL76, aberrant spindles were increased compared to control cells. However, cells with supernumerary centrosomes were marginally increased in UL76-expressing cells relative to control cells. We further demonstrated that UL76-expressing cells activated the DNA damage signal γ-H2AX and caused foci formation in nuclei. In addition, the number of cells with DNA breaks increased in proportion to UL76 protein levels. Conclusion Our findings suggest that the virus-associated protein UL76 induces DNA damage and the accumulation of chromosome aberrations. PMID:19930723

  9. Biocompatibility of Different Nerve Tubes

    PubMed Central

    Stang, Felix; Keilhoff, Gerburg; Fansa, Hisham

    2009-01-01

    Bridging nerve gaps with suitable grafts is a major clinical problem. The autologous nerve graft is considered to be the gold standard, providing the best functional results; however, donor site morbidity is still a major disadvantage. Various attempts have been made to overcome the problems of autologous nerve grafts with artificial nerve tubes, which are “ready-to-use” in almost every situation. A wide range of materials have been used in animal models but only few have been applied to date clinically, where biocompatibility is an inevitable prerequisite. This review gives an idea about artificial nerve tubes with special focus on their biocompatibility in animals and humans.

  10. Peripheral nerve hyperexcitability with preterminal nerve and neuromuscular junction remodeling is a hallmark of Schwartz-Jampel syndrome.

    PubMed

    Bauché, Stéphanie; Boerio, Delphine; Davoine, Claire-Sophie; Bernard, Véronique; Stum, Morgane; Bureau, Cécile; Fardeau, Michel; Romero, Norma Beatriz; Fontaine, Bertrand; Koenig, Jeanine; Hantaï, Daniel; Gueguen, Antoine; Fournier, Emmanuel; Eymard, Bruno; Nicole, Sophie

    2013-12-01

    Schwartz-Jampel syndrome (SJS) is a recessive disorder with muscle hyperactivity that results from hypomorphic mutations in the perlecan gene, a basement membrane proteoglycan. Analyses done on a mouse model have suggested that SJS is a congenital form of distal peripheral nerve hyperexcitability resulting from synaptic acetylcholinesterase deficiency, nerve terminal instability with preterminal amyelination, and subtle peripheral nerve changes. We investigated one adult patient with SJS to study this statement in humans. Perlecan deficiency due to hypomorphic mutations was observed in the patient biological samples. Electroneuromyography showed normal nerve conduction, neuromuscular transmission, and compound nerve action potentials while multiple measures of peripheral nerve excitability along the nerve trunk did not detect changes. Needle electromyography detected complex repetitive discharges without any evidence for neuromuscular transmission failure. The study of muscle biopsies containing neuromuscular junctions showed well-formed post-synaptic element, synaptic acetylcholinesterase deficiency, denervation of synaptic gutters with reinnervation by terminal sprouting, and long nonmyelinated preterminal nerve segments. These data support the notion of peripheral nerve hyperexcitability in SJS, which would originate distally from synergistic actions of peripheral nerve and neuromuscular junction changes as a result of perlecan deficiency. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. Treatment of soft-tissue loss with nerve defect in the finger using the boomerang nerve flap.

    PubMed

    Chen, Chao; Tang, Peifu; Zhang, Xu

    2013-01-01

    This study reports simultaneous repair of soft-tissue loss and proper digital nerve defect in the finger using a boomerang nerve flap including nerve graft from the dorsal branch of the proper digital nerve. From July of 2007 to May of 2010, the flap was used in 17 fingers in 17 patients. The injured fingers included five index, seven long, and five ring fingers. The mean soft-tissue loss was 2.5 × 1.9 cm. The mean flap size was 2.8 × 2.1 cm. Proper digital nerve defects were reconstructed using nerve graft harvested from the dorsal branch of the adjacent finger's proper digital nerve. The average nerve graft length was 2.5 cm. The comparison group included 32 patients treated using a cross-finger flap and a secondary free nerve graft. In the study group, 15 flaps survived completely. Partial necrosis at the distal edge of the flap occurred in two cases. At a mean follow-up of 22 months, the average static two-point discrimination and Semmes-Weinstein monofilament test results on the pulp of the reconstructed finger were 7.5 mm and 3.86, respectively. In the comparison group, the results were 9.3 mm and 3.91, respectively. The study group presented better discriminatory sensation on the pulp and milder pain and cold intolerance in the reconstructed finger. The boomerang nerve flap is useful and reliable for reconstructing complicated finger damage involving soft-tissue loss and nerve defect, especially in difficult anatomical regions. Therapeutic, II.

  12. A model of chromosome aberration induction: applications to space research.

    PubMed

    Ballarini, Francesca; Ottolenghi, Andrea

    2005-10-01

    A mechanistic model and Monte Carlo code simulating chromosome aberration induction in human lymphocytes is presented. The model is based on the assumption that aberrations arise from clustered DNA lesions and that only the free ends of clustered lesions created in neighboring chromosome territories or in the same territory can join and produce exchanges. The lesions are distributed in the cell nucleus according to the radiation track structure. Interphase chromosome territories are modeled as compact intranuclear regions with volumes proportional to the chromosome DNA contents. Both Giemsa staining and FISH painting can be simulated, and background aberrations can be taken into account. The good agreement with in vitro data provides validation of the model in terms of both the assumptions adopted and the simulation techniques. As an application in the field of space research, the model predictions were compared with aberration yields measured among crew members of long-term missions on board Mir and ISS, assuming an average radiation quality factor of 2.4. The agreement obtained also validated the model for in vivo exposure scenarios and suggested possible applications to the prediction of other relevant aberrations, typically translocations.

  13. Intraoperative Ultrasound for Peripheral Nerve Applications.

    PubMed

    Willsey, Matthew; Wilson, Thomas J; Henning, Phillip Troy; Yang, Lynda J-S

    2017-10-01

    Offering real-time, high-resolution images via intraoperative ultrasound is advantageous for a variety of peripheral nerve applications. To highlight the advantages of ultrasound, its extraoperative uses are reviewed. The current intraoperative uses, including nerve localization, real-time evaluation of peripheral nerve tumors, and implantation of leads for peripheral nerve stimulation, are reviewed. Although intraoperative peripheral nerve localization has been performed previously using guide wires and surgical dyes, the authors' approach using ultrasound-guided instrument clamps helps guide surgical dissection to the target nerve, which could lead to more timely operations and shorter incisions. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. A Biosynthetic Nerve Guide Conduit Based on Silk/SWNT/Fibronectin Nanocomposite for Peripheral Nerve Regeneration

    PubMed Central

    Mottaghitalab, Fatemeh; Farokhi, Mehdi; Zaminy, Arash; Kokabi, Mehrdad; Soleimani, Masoud; Mirahmadi, Fereshteh

    2013-01-01

    As a contribution to the functionality of nerve guide conduits (NGCs) in nerve tissue engineering, here we report a conduit processing technique through introduction and evaluation of topographical, physical and chemical cues. Porous structure of NGCs based on freeze-dried silk/single walled carbon nanotubes (SF/SWNTs) has shown a uniform chemical and physical structure with suitable electrical conductivity. Moreover, fibronectin (FN) containing nanofibers within the structure of SF/SWNT conduits produced through electrospinning process have shown aligned fashion with appropriate porosity and diameter. Moreover, fibronectin remained its bioactivity and influenced the adhesion and growth of U373 cell lines. The conduits were then implanted to 10 mm left sciatic nerve defects in rats. The histological assessment has shown that nerve regeneration has taken places in proximal region of implanted nerve after 5 weeks following surgery. Furthermore, nerve conduction velocities (NCV) and more myelinated axons were observed in SF/SWNT and SF/SWNT/FN groups after 5 weeks post implantation, indicating a functional recovery for the injured nerves. With immunohistochemistry, the higher S-100 expression of Schwann cells in SF/SWNT/FN conduits in comparison to other groups was confirmed. In conclusion, an oriented conduit of biocompatible SF/SWNT/FN has been fabricated with acceptable structure that is particularly applicable in nerve grafts. PMID:24098649

  15. Use of Vein Conduit and Isolated Nerve Graft in Peripheral Nerve Repair: A Comparative Study

    PubMed Central

    Ahmad, Imran; Akhtar, Md. Sohaib

    2014-01-01

    Aims and Objectives. The aim of this study was to evaluate the effectiveness of vein conduit in nerve repair compared with isolated nerve graft. Materials and Methods. This retrospective study was conducted at author's centre and included a total of 40 patients. All the patients had nerve defect of more than 3 cm and underwent nerve repair using nerve graft from sural nerve. In 20 cases, vein conduit (study group) was used whereas no conduit was used in other 20 cases. Patients were followed up for 2 years at the intervals of 3 months. Results. Patients had varying degree of recovery. Sensations reached to all the digits at 1 year in study groups compared to 18 months in control group. At the end of second year, 84% patients of the study group achieved 2-point discrimination of <10 mm compared to 60% only in control group. In terms of motor recovery, 82% patients achieved satisfactory hand function in study group compared to 56% in control group (P < .05). Conclusions. It was concluded that the use of vein conduit in peripheral nerve repair is more effective method than isolated nerve graft providing good sensory and motor recovery. PMID:25405029

  16. The cranial nerve skywalk: A 3D tutorial of cranial nerves in a virtual platform.

    PubMed

    Richardson-Hatcher, April; Hazzard, Matthew; Ramirez-Yanez, German

    2014-01-01

    Visualization of the complex courses of the cranial nerves by students in the health-related professions is challenging through either diagrams in books or plastic models in the gross laboratory. Furthermore, dissection of the cranial nerves in the gross laboratory is an extremely meticulous task. Teaching and learning the cranial nerve pathways is difficult using two-dimensional (2D) illustrations alone. Three-dimensional (3D) models aid the teacher in describing intricate and complex anatomical structures and help students visualize them. The study of the cranial nerves can be supplemented with 3D, which permits the students to fully visualize their distribution within the craniofacial complex. This article describes the construction and usage of a virtual anatomy platform in Second Life™, which contains 3D models of the cranial nerves III, V, VII, and IX. The Cranial Nerve Skywalk features select cranial nerves and the associated autonomic pathways in an immersive online environment. This teaching supplement was introduced to groups of pre-healthcare professional students in gross anatomy courses at both institutions and student feedback is included. © 2014 American Association of Anatomists.

  17. Tibial nerve (image)

    MedlinePlus

    ... nerve is commonly injured by fractures or other injury to the back of the knee or the lower leg. It may be affected by systemic diseases such as diabetes mellitus. The nerve can also be damaged by pressure from a tumor, abscess, or bleeding into the ...

  18. Temporal Dependence of Chromosomal Aberration on Radiation Quality and Cellular Genetic Background

    NASA Technical Reports Server (NTRS)

    Lu, Tao; Zhang, Ye; Krieger, Stephanie; Yeshitla, Samrawit; Goss, Rosalin; Bowler, Deborah; Kadhim, Munira; Wilson, Bobby; Wu, Honglu

    2017-01-01

    Radiation induced cancer risks are driven by genetic instability. It is not well understood how different radiation sources induce genetic instability in cells with different genetic background. Here we report our studies on genetic instability, particularly chromosome instability using fluorescence in situ hybridization (FISH), in human primary lymphocytes, normal human fibroblasts, and transformed human mammary epithelial cells in a temporal manner after exposure to high energy protons and Fe ions. The chromosome spread was prepared 48 hours, 1 week, 2 week, and 1 month after radiation exposure. Chromosome aberrations were analyzed with whole chromosome specific probes (chr. 3 and chr. 6). After exposure to protons and Fe ions of similar cumulative energy (??), Fe ions induced more chromosomal aberrations at early time point (48 hours) in all three types of cells. Over time (after 1 month), more chromosome aberrations were observed in cells exposed to Fe ions than in the same type of cells exposed to protons. While the mammary epithelial cells have higher intrinsic genetic instability and higher rate of initial chromosome aberrations than the fibroblasts, the fibroblasts retained more chromosomal aberration after long term cell culture (1 month) in comparison to their initial frequency of chromosome aberration. In lymphocytes, the chromosome aberration frequency at 1 month after exposure to Fe ions was close to unexposed background, and the chromosome aberration frequency at 1 month after exposure to proton was much higher. In addition to human cells, mouse bone marrow cells isolated from strains CBA/CaH and C57BL/6 were irradiated with proton or Fe ions and were analyzed for chromosome aberration at different time points. Cells from CBA mice showed similar frequency of chromosome aberration at early and late time points, while cells from C57 mice showed very different chromosome aberration rate at early and late time points. Our results suggest that relative

  19. The influence of predegenerated nerve grafts on axonal regeneration from prelesioned peripheral nerves.

    PubMed

    Hasan, N A; Neumann, M M; de Souky, M A; So, K F; Bedi, K S

    1996-10-01

    Recent in vitro work has indicated that predegenerated segments of peripheral nerve are more capable of supporting neurite growth from adult neurons than fresh segments of nerve, whereas previous in vivo studies which investigated whether predegenerated nerve segments used as grafts are capable of enhancing axonal regeneration produced conflicting results. We have reinvestigated this question by using predegenerated nerve grafts in combination with conditioning lesions of the host nerve to determine the optimal conditions for obtaining the maximal degree of regeneration of myelinated axons. The sciatic nerve of adult Dark Agouti rats were sectioned at midthigh level, and the distal portion was allowed to predegenerate for 0, 6 or 12 d in situ. 10-15 mm lengths of these distal nerve segments were then syngenically grafted onto the central stumps of sciatic nerves which had themselves received a conditioning lesion 0, 6, and 12 d previously, making a total of 9 different donor-host combinations. The grafts were assessed histologically 3 or 8 wk after grafting. Axonal regeneration in the 9 different donor-host combinations was determined by counting the numbers of myelinated axons in transverse sections through the grafts. All grafts examined contained regenerating myelinated axons. The rats given a 3 wk postgrafting survival period had an average of between 1400 and 5300 such axons. The rats given an 8 wk postgrafting survival period had between about 13,000 and 25,000 regenerating myelinated axons. Analysis of variance revealed significant main effects for both the Donor and Host conditions as well as Weeks (i.e. survival period after grafting). These results indicate that both a conditioning lesion of the host neurons and the degree of predegeneration of peripheral nerve segments to be used as grafts are of importance in influencing the degree of axonal regeneration. Of these 2 factors the conditioning lesion of the host appears to have the greater effect on the

  20. Combined KHFAC + DC nerve block without onset or reduced nerve conductivity after block

    NASA Astrophysics Data System (ADS)

    Franke, Manfred; Vrabec, Tina; Wainright, Jesse; Bhadra, Niloy; Bhadra, Narendra; Kilgore, Kevin

    2014-10-01

    Objective. Kilohertz frequency alternating current (KHFAC) waveforms have been shown to provide peripheral nerve conductivity block in many acute and chronic animal models. KHFAC nerve block could be used to address multiple disorders caused by neural over-activity, including blocking pain and spasticity. However, one drawback of KHFAC block is a transient activation of nerve fibers during the initiation of the nerve block, called the onset response. The objective of this study is to evaluate the feasibility of using charge balanced direct current (CBDC) waveforms to temporarily block motor nerve conductivity distally to the KHFAC electrodes to mitigate the block onset-response. Approach. A total of eight animals were used in this study. A set of four animals were used to assess feasibility and reproducibility of a combined KHFAC + CBDC block. A following randomized study, conducted on a second set of four animals, compared the onset response resulting from KHFAC alone and combined KHFAC + CBDC waveforms. To quantify the onset, peak forces and the force-time integral were measured during KHFAC block initiation. Nerve conductivity was monitored throughout the study by comparing muscle twitch forces evoked by supra-maximal stimulation proximal and distal to the block electrodes. Each animal of the randomized study received at least 300 s (range: 318-1563 s) of cumulative dc to investigate the impact of combined KHFAC + CBDC on nerve viability. Main results. The peak onset force was reduced significantly from 20.73 N (range: 18.6-26.5 N) with KHFAC alone to 0.45 N (range: 0.2-0.7 N) with the combined CBDC and KHFAC block waveform (p < 0.001). The area under the force curve was reduced from 6.8 Ns (range: 3.5-21.9 Ns) to 0.54 Ns (range: 0.18-0.86 Ns) (p < 0.01). No change in nerve conductivity was observed after application of the combined KHFAC + CBDC block relative to KHFAC waveforms. Significance. The distal application of CBDC can significantly reduce or even

  1. The BHVI-EyeMapper: peripheral refraction and aberration profiles.

    PubMed

    Fedtke, Cathleen; Ehrmann, Klaus; Falk, Darrin; Bakaraju, Ravi C; Holden, Brien A

    2014-10-01

    The aim of this article was to present the optical design of a new instrument (BHVI-EyeMapper, EM), which is dedicated to rapid peripheral wavefront measurements across the visual field for distance and near, and to compare the peripheral refraction and higher-order aberration profiles obtained in myopic eyes with and without accommodation. Central and peripheral refractive errors (M, J180, and J45) and higher-order aberrations (C[3, 1], C[3, 3], and C[4, 0]) were measured in 26 myopic participants (mean [±SD] age, 20.9 [±2.0] years; mean [±SD] spherical equivalent, -3.00 [±0.90] diopters [D]) corrected for distance. Measurements were performed along the horizontal visual field with (-2.00 to -5.00 D) and without (+1.00 D fogging) accommodation. Changes as a function of accommodation were compared using tilt and curvature coefficients of peripheral refraction and aberration profiles. As accommodation increased, the relative peripheral refraction profiles of M and J180 became significantly (p < 0.05) more negative and the profile of M became significantly (p < 0.05) more asymmetric. No significant differences were found for the J45 profiles (p > 0.05). The peripheral aberration profiles of C[3, 1], C[3, 3], and C[4, 0] became significantly (p < 0.05) less asymmetric as accommodation increased, but no differences were found in the curvature. The current study showed that significant changes in peripheral refraction and higher-order aberration profiles occurred during accommodation in myopic eyes. With its extended measurement capabilities, that is, permitting rapid peripheral refraction and higher-order aberration measurements up to visual field angles of ±50 degrees for distance and near (up to -5.00 D), the EM is a new advanced instrument that may provide additional insights in the ongoing quest to understand and monitor myopia development.

  2. Correction of ultrasonic wave aberration with a time delay and amplitude filter.

    PubMed

    Måsøy, Svein-Erik; Johansen, Tonni F; Angelsen, Bjørn

    2003-04-01

    Two-dimensional simulations with propagation through two different heterogeneous human body wall models have been performed to analyze different correction filters for ultrasonic wave aberration due to forward wave propagation. The different models each produce most of the characteristic aberration effects such as phase aberration, relatively strong amplitude aberration, and waveform deformation. Simulations of wave propagation from a point source in the focus (60 mm) of a 20 mm transducer through the body wall models were performed. Center frequency of the pulse was 2.5 MHz. Corrections of the aberrations introduced by the two body wall models were evaluated with reference to the corrections obtained with the optimal filter: a generalized frequency-dependent phase and amplitude correction filter [Angelsen, Ultrasonic Imaging (Emantec, Norway, 2000), Vol. II]. Two correction filters were applied, a time delay filter, and a time delay and amplitude filter. Results showed that correction with a time delay filter produced substantial reduction of the aberration in both cases. A time delay and amplitude correction filter performed even better in both cases, and gave correction close to the ideal situation (no aberration). The results also indicated that the effect of the correction was very sensitive to the accuracy of the arrival time fluctuations estimate, i.e., the time delay correction filter.

  3. Aberration analysis and calculation in system of Gaussian beam illuminates lenslet array

    NASA Astrophysics Data System (ADS)

    Zhao, Zhu; Hui, Mei; Zhou, Ping; Su, Tianquan; Feng, Yun; Zhao, Yuejin

    2014-09-01

    Low order aberration was founded when focused Gaussian beam imaging at Kodak KAI -16000 image detector, which is integrated with lenslet array. Effect of focused Gaussian beam and numerical simulation calculation of the aberration were presented in this paper. First, we set up a model of optical imaging system based on previous experiment. Focused Gaussian beam passed through a pinhole and was received by Kodak KAI -16000 image detector whose microlenses of lenslet array were exactly focused on sensor surface. Then, we illustrated the characteristics of focused Gaussian beam and the effect of relative space position relations between waist of Gaussian beam and front spherical surface of microlenses to the aberration. Finally, we analyzed the main element of low order aberration and calculated the spherical aberration caused by lenslet array according to the results of above two steps. Our theoretical calculations shown that , the numerical simulation had a good agreement with the experimental result. Our research results proved that spherical aberration was the main element and made up about 93.44% of the 48 nm error, which was demonstrated in previous experiment. The spherical aberration is inversely proportional to the value of divergence distance between microlens and waist, and directly proportional to the value of the Gaussian beam waist radius.

  4. Use of nerve conduits for peripheral nerve injury repair: A Web of Science-based literature analysis.

    PubMed

    Nan, Jinniang; Hu, Xuguang; Li, Hongxiu; Zhang, Xiaonong; Piao, Renjing

    2012-12-15

    To identify global research trends in the use of nerve conduits for peripheral nerve injury repair. Numerous basic and clinical studies on nerve conduits for peripheral nerve injury repair were performed between 2002-2011. We performed a bibliometric analysis of the institutions, authors, and hot topics in the field, from the Web of Science, using the key words peripheral nerve and conduit or tube. peer-reviewed published articles on nerve conduits for peripheral nerve injury repair, indexed in the Web of Science; original research articles, reviews, meeting abstracts, proceedings papers, book chapters, editorial material, and news items. articles requiring manual searching or telephone access; documents not published in the public domain; and several corrected papers. (a) Annual publication output; (b) publication type; (c) publication by research field; (d) publication by journal; (e) publication by funding agency; (f) publication by author; (g) publication by country and institution; (h) publications by institution in China; (i) most-cited papers. A total of 793 publications on the use of nerve conduits for peripheral nerve injury repair were retrieved from the Web of Science between 2002-2011. The number of publications gradually increased over the 10-year study period. Articles constituted the main type of publication. The most prolific journals were Biomaterials, Microsurgery, and Journal of Biomedical Materials Research Part A. The National Natural Science Foundation of China supported 27 papers, more than any other funding agency. Of the 793 publications, almost half came from American and Chinese authors and institutions. Nerve conduits have been studied extensively for peripheral nerve regeneration; however, many problems remain in this field, which are difficult for researchers to reach a consensus.

  5. Balanced levels of nerve growth factor are required for normal pregnancy progression.

    PubMed

    Frank, Pierre; Barrientos, Gabriela; Tirado-González, Irene; Cohen, Marie; Moschansky, Petra; Peters, Eva M; Klapp, Burghard F; Rose, Matthias; Tometten, Mareike; Blois, Sandra M

    2014-08-01

    Nerve growth factor (NGF), the first identified member of the family of neurotrophins, is thought to play a critical role in the initiation of the decidual response in stress-challenged pregnant mice. However, the contribution of this pathway to physiological events during the establishment and maintenance of pregnancy remains largely elusive. Using NGF depletion and supplementation strategies alternatively, in this study, we demonstrated that a successful pregnancy is sensitive to disturbances in NGF levels in mice. Treatment with NGF further boosted fetal loss rates in the high-abortion rate CBA/J x DBA/2J mouse model by amplifying a local inflammatory response through recruitment of NGF-expressing immune cells, increased decidual innervation with substance P(+) nerve fibres and a Th1 cytokine shift. Similarly, treatment with a NGF-neutralising antibody in BALB/c-mated CBA/J mice, a normal-pregnancy model, also induced abortions associated with increased infiltration of tropomyosin kinase receptor A-expressing NK cells to the decidua. Importantly, in neither of the models, pregnancy loss was associated with defective ovarian function, angiogenesis or placental development. We further demonstrated that spontaneous abortion in humans is associated with up-regulated synthesis and an aberrant distribution of NGF in placental tissue. Thus, a local threshold of NGF expression seems to be necessary to ensure maternal tolerance in healthy pregnancies, but when surpassed may result in fetal rejection due to exacerbated inflammation. © 2014 Society for Reproduction and Fertility.

  6. Aberration correction results in the IBM STEM instrument.

    PubMed

    Batson, P E

    2003-09-01

    Results from the installation of aberration correction in the IBM 120 kV STEM argue that a sub-angstrom probe size has been achieved. Results and the experimental methods used to obtain them are described here. Some post-experiment processing is necessary to demonstrate the probe size of about 0.078 nm. While the promise of aberration correction is demonstrated, we remain at the very threshold of practicality, given the very stringent stability requirements.

  7. Aberration compensation of an ultrasound imaging instrument with a reduced number of channels.

    PubMed

    Jiang, Wei; Astheimer, Jeffrey P; Waag, Robert C

    2012-10-01

    Focusing and imaging qualities of an ultrasound imaging system that uses aberration correction were experimentally investigated as functions of the number of parallel channels. Front-end electronics that consolidate signals from multiple physical elements can be used to lower hardware and computational costs by reducing the number of parallel channels. However, the signals from sparse arrays of synthetic elements yield poorer aberration estimates. In this study, aberration estimates derived from synthetic arrays of varying element sizes are evaluated by comparing compensated receive focuses, compensated transmit focuses, and compensated b-scan images of a point target and a cyst phantom. An array of 80 x 80 physical elements with a pitch of 0.6 x 0.6 mm was used for all of the experiments and the aberration was produced by a phantom selected to mimic propagation through abdominal wall. The results show that aberration correction derived from synthetic arrays with pitches that have a diagonal length smaller than 70% of the correlation length of the aberration yield focuses and images of approximately the same quality. This connection between correlation length of the aberration and synthetic element size provides a guideline for determining the number of parallel channels that are required when designing imaging systems that employ aberration correction.

  8. Suprascapular nerve entrapment in newsreel cameramen.

    PubMed

    Karataş, Gülçin Kaymak; Göğüş, Feride

    2003-03-01

    To determine presence of suprascapular nerve entrapment in a group of newsreel cameramen. Thirty-six men working as newsreel cameramen participated in the study. In addition to musculoskeletal and neurologic examinations, bilateral suprascapular nerve conduction studies and needle electromyography were performed. A group of 19 healthy, male volunteers were included in the study as normal controls for suprascapular nerve conduction studies. In newsreel cameramen, mean suprascapular nerve latency was 3.20 +/- 0.56 msec and 2.84 +/- 0.36 msec for right and left shoulders, respectively (P = 0.001). The mean latency difference between right and left suprascapular nerves was -0.05 +/- 0.19 msec in the control group and 0.36 +/- 0.58 msec in the cameramen group (P < 0.001). Six subjects' right suprascapular nerve motor latencies were 2 SD above the normal mean values. There was no relationship between suprascapular nerve latencies and the age, professional life, and number of hours worked daily by the subjects. Carrying a heavy, mobile camera on the shoulder might cause suprascapular nerve entrapment in newsreel cameramen. This could be considered an occupational disorder of the suprascapular nerve, like meat-packer's neuropathy.

  9. Nerve Impulses in Plants

    ERIC Educational Resources Information Center

    Blatt, F. J.

    1974-01-01

    Summarizes research done on the resting and action potential of nerve impulses, electrical excitation of nerve cells, electrical properties of Nitella, and temperature effects on action potential. (GS)

  10. Aberrant Breast in a Rare Site: A Case Report

    PubMed Central

    Yeniay, Levent; Mulailwa, Kilongo; Asgerov, Elmir; Hoşcoşkun, Cüneyt; Zekioğlu, Osman

    2012-01-01

    Aberrant breast tissue is an anomaly in the embryogenesis of the breast that is found along the mammary ridge or out of that line. We report a case of a 71-year-old female patient with an abdominal aberrant breast tissue found incidentally in a piece of mesenteric biopsy. The histological features were consistent with breast tissue. PMID:22792115

  11. Influence of alignment errors of a telescope system on its aberration field

    NASA Astrophysics Data System (ADS)

    Shack, R. V.; Thompson, K.

    1980-01-01

    The study of aberrations in a system is considered. It is pointed out that a system in which the elements are tilted and decentered has no axial symmetry, and in fact no symmetry at all if the tilts, and decentrations are not coplanar. It is customary in such a case to give up on an aberration-theoretic treatment and simply trace enough rays to produce a set of spot diagrams for various points in the field. However, in connection with the lack of symmetry, it is necessary to select a relatively large number of points. The considered investigation is concerned with an aberration-theoretic approach which can be applied to such systems. This approach provides insight into the field behavior of the aberrations with great economy in the calculation. It is based on a concept suggested by Buchroeder (1976). In the given case, this concept considers for the component fields corresponding to the various surfaces centers of symmetry which do not coincide. Attention is given to the procedure for locating the centers of symmetry, aberrations fields, spherical aberration, and various types of astigmatism.

  12. Comparing the Efficacy of Triple Nerve Transfers with Nerve Graft Reconstruction in Upper Trunk Obstetric Brachial Plexus Injury.

    PubMed

    O'Grady, Kathleen M; Power, Hollie A; Olson, Jaret L; Morhart, Michael J; Harrop, A Robertson; Watt, M Joe; Chan, K Ming

    2017-10-01

    Upper trunk obstetric brachial plexus injury can cause profound shoulder and elbow dysfunction. Although neuroma excision with interpositional sural nerve grafting is the current gold standard, distal nerve transfers have a number of potential advantages. The goal of this study was to compare the clinical outcomes and health care costs between nerve grafting and distal nerve transfers in children with upper trunk obstetric brachial plexus injury. In this prospective cohort study, children who underwent triple nerve transfers were followed with the Active Movement Scale for 2 years. Their outcomes were compared to those of children who underwent nerve graft reconstruction. To assess health care use, a cost analysis was also performed. Twelve patients who underwent nerve grafting were compared to 14 patients who underwent triple nerve transfers. Both groups had similar baseline characteristics and showed improved shoulder and elbow function following surgery. However, the nerve transfer group displayed significantly greater improvement in shoulder external rotation and forearm supination 2 years after surgery (p < 0.05). The operative time and length of hospital stay were significantly lower (p < 0.05), and the overall cost was approximately 50 percent less in the nerve transfer group. Triple nerve transfer for upper trunk obstetric brachial plexus injury is a feasible option, with better functional shoulder external rotation and forearm supination, faster recovery, and lower cost compared with traditional nerve graft reconstruction. Therapeutic, II.

  13. Nerve-sparing abdominal radical trachelectomy: a novel concept to preserve uterine branches of pelvic nerves.

    PubMed

    Kyo, Satoru; Mizumoto, Yasunari; Takakura, Masahiro; Nakamura, Mitsuhiro; Sato, Emi; Katagiri, Hiroshi; Ishikawa, Masako; Nakayama, Kentaro; Fujiwara, Hiroshi

    2015-10-01

    Nerve-sparing techniques to avoid bladder dysfunction in abdominal radical hysterectomy have been established during the past two decades, and they have been applied to radical trachelectomy. Although trachelectomy retains the uterine corpus, no report mentions the preservation of uterine branches of pelvic nerves. The aim of the present study was to introduce and discuss our unique concept for preserving them. Four cases with FIGO stage Ia2-Ib1 cervical cancer, in which preservation of uterine branches of the pelvic nerves was attempted, are presented. Operative procedures basically followed the previously reported standard approaches for nerve-sparing radical hysterectomy or trachelectomy, except for some points. Before resection of the sacrouterine ligament, the hypogastric nerve was first identified and translocated laterally. Subsequently, the uterine branches of the pelvic nerve were identified as a continuation of the hypogastric nerve and could be scooped with forceps by detachment of the surrounding connective tissues. Further detachment toward the uterine corpus enabled them to be completely separated from the cervix. This separation was extended up to the level of the junction of the upper and lower branches of the uterine artery. Thereafter, standard resection of the parametrium and paracolpium was performed, followed by cervical resection when it was confirmed that the isolated uterine branches of the pelvic nerves were safely translocated and preserved. There were no recurrences of cancer in these patients. Uterine branches of autonomic nerves can be safely preserved, and the procedure may be considered one of the nerve-sparing techniques for radical abdominal trachelectomy, which may hopefully improve the reproductive outcomes of this operation, although it needs to be evaluated with more patients. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  14. Inferior alveolar nerve block: Alternative technique.

    PubMed

    Thangavelu, K; Kannan, R; Kumar, N Senthil

    2012-01-01

    Inferior alveolar nerve block (IANB) is a technique of dental anesthesia, used to produce anesthesia of the mandibular teeth, gingivae of the mandible and lower lip. The conventional IANB is the most commonly used the nerve block technique for achieving local anesthesia for mandibular surgical procedures. In certain cases, however, this nerve block fails, even when performed by the most experienced clinician. Therefore, it would be advantageous to find an alternative simple technique. The objective of this study is to find an alternative inferior alveolar nerve block that has a higher success rate than other routine techniques. To this purpose, a simple painless inferior alveolar nerve block was designed to anesthetize the inferior alveolar nerve. This study was conducted in Oral surgery department of Vinayaka Mission's dental college Salem from May 2009 to May 2011. Five hundred patients between the age of 20 years and 65 years who required extraction of teeth in mandible were included in the study. Out of 500 patients 270 were males and 230 were females. The effectiveness of the IANB was evaluated by using a sharp dental explorer in the regions innervated by the inferior alveolar, lingual, and buccal nerves after 3, 5, and 7 min, respectively. This study concludes that inferior alveolar nerve block is an appropriate alternative nerve block to anesthetize inferior alveolar nerve due to its several advantages.

  15. Aberration Theory and Design Techniques for Refracting Prism Systems.

    NASA Astrophysics Data System (ADS)

    Al-Bizri, N.

    Available from UMI in association with The British Library. The general case of image formation by optical systems consisting of combinations of ordinary lens components and refracting prisms is studied in detail. Formulae for the sagittal and tangential magnifications, the pupil scale ratios, the image tilt, the positions of (newly defined) principal planes and the equivalent focal lengths have been derived. Formulae for the axial astigmatism, axial transverse chromatic aberration and the focal shift measure of the aberration due to the tilt of the image plane have also been obtained. All of these formulae are equally valid for any optical system which has a single plane of symmetry. The calculation of the wavefront aberration coefficients and of the variance of the aberration for such systems has been treated using the pre-inverted matrix method. In addition formulae for the numerical evaluation of the optical transfer function, the point spread function, the line spread function and the edge response function, have been obtained and programmed. First-order formulae, and a refinement technique, for the design of cemented refracting doublet prisms have been obtained, which ensure that the desired prismatic deviation of the axis is obtained, and that the axial astigmatism and the axial transverse chromatic aberration have stipulated target values. All of the above formulae have been carefully tested by numerical examples, and the design technique has been used to design endoscope objectives which provide small deviations (<10^circ ) of the optical axis.

  16. A novel electrospun nerve conduit enhanced by carbon nanotubes for peripheral nerve regeneration

    NASA Astrophysics Data System (ADS)

    Yu, Wenwen; Jiang, Xinquan; Cai, Ming; Zhao, Wen; Ye, Dongxia; Zhou, Yong; Zhu, Chao; Zhang, Xiuli; Lu, Xiaofeng; Zhang, Zhiyuan

    2014-04-01

    For artificial nerve conduits, great improvements have been achieved in mimicking the structures and components of autologous nerves. However, there are still some problems in conduit construction, especially in terms of mechanical properties, biomimetic surface tomography, electrical conductivity and sustained release of neurotrophic factors or cells. In this study, we designed and fabricated a novel electrospun nerve conduit enhanced by multi-walled carbon nanotubes (MWNTs) on the basis of a collagen/poly(ɛ-caprolactone) (collagen/PCL) fibrous scaffold. Our aim was to provide further knowledge about the mechanical effects and efficacy of MWNTs on nerve conduits as well as the biocompatibility and toxicology of MWNTs when applied in vivo. The results showed that as one component, carboxyl MWNTs could greatly alter the composite scaffold’s hydrophilicity, mechanical properties and degradability. The electrospun fibers enhanced by MWNTs could support Schwann cell adhesion and elongation as a substrate in vitro. In vivo animal studies demonstrated that the MWNT-enhanced collagen/PCL conduit could effectively promote nerve regeneration of sciatic nerve defect in rats and prevent muscle atrophy without invoking body rejection or serious chronic inflammation. All of these results showed that this MWNT-enhanced scaffold possesses good biocompatibility and MWNTs might be excellent candidates as engineered nanocarriers for further neurotrophic factor delivery research.

  17. A novel electrospun nerve conduit enhanced by carbon nanotubes for peripheral nerve regeneration.

    PubMed

    Yu, Wenwen; Jiang, Xinquan; Cai, Ming; Zhao, Wen; Ye, Dongxia; Zhou, Yong; Zhu, Chao; Zhang, Xiuli; Lu, Xiaofeng; Zhang, Zhiyuan

    2014-04-25

    For artificial nerve conduits, great improvements have been achieved in mimicking the structures and components of autologous nerves. However, there are still some problems in conduit construction, especially in terms of mechanical properties, biomimetic surface tomography, electrical conductivity and sustained release of neurotrophic factors or cells. In this study, we designed and fabricated a novel electrospun nerve conduit enhanced by multi-walled carbon nanotubes (MWNTs) on the basis of a collagen/poly(ε-caprolactone) (collagen/PCL) fibrous scaffold. Our aim was to provide further knowledge about the mechanical effects and efficacy of MWNTs on nerve conduits as well as the biocompatibility and toxicology of MWNTs when applied in vivo.The results showed that as one component, carboxyl MWNTs could greatly alter the composite scaffold's hydrophilicity, mechanical properties and degradability. The electrospun fibers enhanced by MWNTs could support Schwann cell adhesion and elongation as a substrate in vitro. In vivo animal studies demonstrated that the MWNT-enhanced collagen/PCL conduit could effectively promote nerve regeneration of sciatic nerve defect in rats and prevent muscle atrophy without invoking body rejection or serious chronic inflammation. All of these results showed that this MWNT-enhanced scaffold possesses good biocompatibility and MWNTs might be excellent candidates as engineered nanocarriers for further neurotrophic factor delivery research.

  18. Neurotization of the phrenic nerve with accessory nerve for high cervical spinal cord injury with respiratory distress: an anatomic study.

    PubMed

    Wang, Ce; Zhang, Ying; Nicholas, Tsai; Wu, Guoxin; Shi, Sheng; Bo, Yin; Wang, Xinwei; Zhou, Xuhui; Yuan, Wen

    2014-01-01

    High cervical spinal cord injury is associated with high morbidity and mortality. Traditional treatments carry various complications such as infection, pacemaker failure and undesirable movement. Thus, a secure surgical strategy with fewer complications analogous to physiological ventilation is still required. We hope to offer one potential method to decrease the complications and improve survival qualities of patients from the aspect of anatomy. The purpose of the study is to provide anatomic details on the accessory nerve and phrenic nerve for neurotization in patients with high spinal cord injuries. 38 cadavers (76 accessory and 76 phrenic nerves) were dissected in the study. The width, length and thickness of each accessory nerve and phrenic nerve above clavicle were measured. The distances from several landmarks on accessory nerve to the origin and the end of the phrenic nerve above clavicle were measured too. Then, the number of motor nerve fibers on different sections of the nerves was calculated using the technique of immunohistochemistry. The accessory nerves distal to its sternocleidomastoid muscular branches were 1.52 ± 0.32 mm ~1.54 ± 0.29 mm in width, 0.52 ± 0.18 mm ~ 0.56 ± 0.20mm in thickness and 9.52 ± 0.98 cm in length. And the phrenic nerves above clavicle were 1.44 ± 0.23 mm ~ 1.45 ± 0.24 mm in width, 0.47 ± 0.15 mm ~ 0.56 ± 0.25 mm in thickness and 6.48 ± 0.78 cm in length. The distance between the starting point of accessory nerve and phrenic nerve were 3.24 ± 1.17 cm, and the distance between the starting point of accessory nerve and the end of the phrenic nerve above clavicle were 8.72 ± 0.84 cm. The numbers of motor nerve fibers in accessory nerve were 1,038 ± 320~1,102 ± 216, before giving out the sternocleidomastoid muscular branches. The number of motor nerve fibers in the phrenic nerve was 911 ± 321~1,338 ± 467. The accessory nerve and the phrenic were similar in width, thickness and the number of motor nerve fibers. And

  19. Peripheral neuropathy in the twitcher mouse: accumulation of extracellular matrix in the endoneurium and aberrant expression of ion channels.

    PubMed

    Kagitani-Shimono, Kuriko; Mohri, Ikuko; Yagi, Takashi; Taniike, Masako; Suzuki, Kinuko

    2008-05-01

    Globoid cell leukodystrophy (GLD; Krabbe's disease), caused by a genetic galactosylceramidase deficiency, affects both the central and peripheral nervous systems (CNS and PNS). Allogenic hematopoietic stem-cell transplantation (HSCT) has been beneficial for clinical improvement of this disease. However, recent reports by Siddiqi et al. suggested that none of their transplanted patients achieved complete normalization of their peripheral nerve function, despite the well-documented remyelination of the CNS and PNS in the treated patients. We hypothesized that the PNS dysfunction in GLD is due to altered Schwann cell-axon interactions, resulting in structural abnormalities of the node of Ranvier and aberrant expression of ion channels caused by demyelination and that the persistence of this altered interaction is responsible for the dysfunction of the PNS after HSCT. Since there has not been any investigation of the Schwann cell-axonal relationship in twitcher mice, an authentic model of GLD, we first investigated structural abnormalities, focusing on the node of Ranvier in untreated twitcher mice, and compared the results with those obtained after receiving bone marrow transplantation (BMT). As expected, we found numerous supernumerary Schwann cells that formed structurally abnormal nodes of Ranvier. Similar findings, though at somewhat variable extent, were detected in mice treated with BMT. Activated supernumerary Schwann cells expressed GFAP immunoreactivity and generated Alcian blue-positive extracellular matrix (ECM) in the endoneurial space. The processes of these supernumerary Schwann cells often covered and obliterated the nodal regions. Furthermore, the distribution of Na(+) channel immunoreactivity was diffuse without the concentration at the nodes of Ranvier as seen in wild-type mice. Neither K(+) channels nor Neurexin IV/ Caspr/ Paranoidin (NCP-1) were detected in the twi/twi sciatic nerve. The results of our study suggest the importance of normalization

  20. A Novel Method of Diagnosing Aberrant Pancreas: Needle-based Confocal Laser Endomicroscopy.

    PubMed

    Yasuda, Muneji; Hara, Kazuo; Kurita, Yusuke; Tanaka, Hiroki; Obata, Masahiro; Kuraoka, Naosuke; Matsumoto, Shimpei; Ito, Ayako; Iwaya, Hiromichi; Toriyama, Kazuhiro; Okuno, Nozomi; Kuwahara, Takamichi; Hijioka, Susumu; Mizuno, Nobumasa; Onishi, Sachiyo; Hirayama, Yutaka; Ishihara, Makoto; Tanaka, Tsutomu; Tajika, Masahiro; Niwa, Yasumasa

    2018-05-18

    Aberrant pancreas is defined as pancreatic tissue present outside of the pancreas and is often found incidentally during esophagogastroduodenoscopy. Obtaining sufficient tissue to differentiate aberrant pancreas from other subepithelial lesions is sometimes difficult. Due to the lack of a definitive diagnosis, patients often undergo unnecessary surgery. We herein report the first case of aberrant pancreas in which the concomitant use of needle-based probe confocal laser endomicroscopy and fine-needle aspiration supported the final diagnosis. Needle-based probe confocal laser endomicroscopy provides a real-time in vivo histopathology evaluation and may be a feasible means of diagnosing aberrant pancreas.

  1. Role of the trochlear nerve in eye abduction and frontal vision of the red-eared slider turtle (Trachemys scripta elegans).

    PubMed

    Dearworth, J R; Ashworth, A L; Kaye, J M; Bednarz, D T; Blaum, J F; Vacca, J M; McNeish, J E; Higgins, K A; Michael, C L; Skrobola, M G; Jones, M S; Ariel, M

    2013-10-15

    Horizontal head rotation evokes significant responses from trochlear motoneurons of turtle that suggests they have a functional role in abduction of the eyes like that in frontal-eyed mammals. The finding is unexpected given that the turtle is generally considered lateral-eyed and assumed to have eye movements instead like that of lateral-eyed mammals, in which innervation of the superior oblique muscle by the trochlear nerve (nIV) produces intorsion, elevation, and adduction (not abduction). Using an isolated turtle head preparation with the brain removed, glass suction electrodes were used to stimulate nIV with trains of current pulses. Eyes were monitored via an infrared camera with the head placed in a gimble to quantify eye rotations and their directions. Stimulations of nIV evoked intorsion, elevation, and abduction. Dissection of the superior oblique muscle identified lines of action and a location of insertion on the eye, which supported kinematics evoked by nIV stimulation. Eye positions in alert behaving turtles with their head extended were compared with that when their heads were retracted in the carapace. When the head was retracted, there was a reduction in interpupillary distance and an increase in binocular overlap. Occlusion of peripheral fields by the carapace forces the turtle to a more frontal-eyed state, perhaps the reason for the action of abduction by the superior oblique muscle. These findings support why trochlear motoneurons in turtle respond in the same way as abducens motoneurons to horizontal rotations, an unusual characteristic of vestibulo-ocular physiology in comparison with other mammalian lateral-eyed species. Copyright © 2013 Wiley Periodicals, Inc.

  2. Microscale Electrode Implantation during Nerve Repair: Effects on Nerve Morphology, Electromyography, and Recovery of Muscle Contractile Function

    PubMed Central

    Urbanchek, Melanie G; Wei, Benjamin; Egeland, Brent M; Abidian, Mohammad R; Kipke, Daryl R; Cederna, Paul S

    2011-01-01

    Background Our goal is to develop a peripheral nerve electrode with long-term stability and fidelity for use in nerve-machine interfaces. Microelectromechanical systems (MEMS) use silicon probes that contain multi-channel actuators, sensors, and electronics. We tested the null hypothesis that implantation of MEMS probes do not have a detrimental effect on peripheral nerve function or regeneration. Methods A rat hindlimb, peroneal nerve model was utilized in all experimental groups: a) intact nerve (Control, n= 10); b) nerve division and repair (Repair, n= 9); and c) Nerve division, insertion of MEMS probe, and repair (Repair + Probe, n=9). Nerve morphology, nerve to muscle compound action potential (CMAP) studies, walking tracks, and extensor digitorum longus (EDL) muscle function tests were evaluated following an 80 day recovery. Results Repair and Repair + Probe showed no differences in axon count, axon size, percent non-neural area, CMAP amplitude, latency, muscle mass, muscle force, or walking track scores. Though there was some local fibrosis around each MEMS probe, this did not lead to measurable detrimental effects in any anatomic or functional outcome measurements. Conclusions The lack of a significant difference between Repair and Repair + Probe groups in histology, CMAP, walking tracks, and muscle force suggests that MEMS electrodes are compatible with regenerating axons and show promise for establishing chemical and electrical interfaces with peripheral nerves. PMID:21921739

  3. An electron microscope for the aberration-corrected era.

    PubMed

    Krivanek, O L; Corbin, G J; Dellby, N; Elston, B F; Keyse, R J; Murfitt, M F; Own, C S; Szilagyi, Z S; Woodruff, J W

    2008-02-01

    Improved resolution made possible by aberration correction has greatly increased the demands on the performance of all parts of high-end electron microscopes. In order to meet these demands, we have designed and built an entirely new scanning transmission electron microscope (STEM). The microscope includes a flexible illumination system that allows the properties of its probe to be changed on-the-fly, a third-generation aberration corrector which corrects all geometric aberrations up to fifth order, an ultra-responsive yet stable five-axis sample stage, and a flexible configuration of optimized detectors. The microscope features many innovations, such as a modular column assembled from building blocks that can be stacked in almost any order, in situ storage and cleaning facilities for up to five samples, computer-controlled loading of samples into the column, and self-diagnosing electronics. The microscope construction is described, and examples of its capabilities are shown.

  4. Swimming Exercise in the Acute or Late Phase after Sciatic Nerve Crush Accelerates Nerve Regeneration

    PubMed Central

    Teodori, Rosana Macher; Betini, Joice; de Oliveira, Larissa Salgado; Sobral, Luciane Lobato; Takeda, Sibele Yoko Mattozo; Montebelo, Maria Imaculada de Lima

    2011-01-01

    There is no consensus about the best time to start exercise after peripheral nerve injury. We evaluated the morphological and functional characteristics of the sciatic nerves of rats that began to swim immediately after crush nerve injury (CS1), those that began to swim 14 days after injury (CS14), injured rats not submitted to swimming (C), and uninjured rats submitted to swimming (S). After 30 days the number of axons in CS1 and CS14 was lower than in C (P < 0.01). The diameter of axons and nerve fibers was larger in CS1 (P < 0.01) and CS14 (P < 0.05) than in C, and myelin sheath thickness was lower in all crushed groups (P < 0.05). There was no functional difference between CS1 and CS14 (P > 0.05). Swimming exercise applied during the acute or late phase of nerve injury accelerated nerve regeneration and synaptic elimination after axonotmesis, suggesting that exercise may be initiated immediately after injury. PMID:21876821

  5. Magnetic resonance imaging of optic nerve

    PubMed Central

    Gala, Foram

    2015-01-01

    Optic nerves are the second pair of cranial nerves and are unique as they represent an extension of the central nervous system. Apart from clinical and ophthalmoscopic evaluation, imaging, especially magnetic resonance imaging (MRI), plays an important role in the complete evaluation of optic nerve and the entire visual pathway. In this pictorial essay, the authors describe segmental anatomy of the optic nerve and review the imaging findings of various conditions affecting the optic nerves. MRI allows excellent depiction of the intricate anatomy of optic nerves due to its excellent soft tissue contrast without exposure to ionizing radiation, better delineation of the entire visual pathway, and accurate evaluation of associated intracranial pathologies. PMID:26752822

  6. Surgical and conservative methods for restoring impaired motor function - facial nerve, spinal accessory nerve, hypoglossal nerve (not including vagal nerve or swallowing)

    PubMed Central

    Laskawi, R.; Rohrbach, S.

    2005-01-01

    The present review gives a survey of rehabilitative measures for disorders of the motor function of the mimetic muscles (facial nerve), and muscles innervated by the spinal accessory and hypoglossal nerves. The dysfunction can present either as paralysis or hyperkinesis (hyperkinesia). Conservative and surgical treatment options aimed at restoring normal motor function and correcting the movement disorders are described. Static reanimation techniques are not dealt with. The final section describes the use of botulinum toxin in the therapy of dysphagia. PMID:22073058

  7. Corneal higher-order aberrations and higher-order Strehl ratio after aberration-free ablation profile to treat compound myopic astigmatism.

    PubMed

    Brenner, Luis F

    2015-12-01

    To evaluate the changes in corneal higher-order aberrations (HOAs) and their impact on corneal higher-order Strehl ratio after aberration-free ablation profile. Verter Institute, H. Olhos, São Paulo, Brazil. Prospective interventional study. Eyes that had aberration-free myopic ablation were divided into 3 groups, based on the spherical equivalent (SE). The corneal HOAs and higher-order Strehl ratios were calculated before surgery and 3 months after surgery. The postoperative uncorrected-distance visual acuity, corrected-distance visual acuity, and SE did not present statistical differences among groups (88 eyes, P > .05). For a 6 mm pupil, the corneal HOA showed a mean increase of 0.17 μm (range 0.39 to 0.56 μm) (P < .001) and the corneal higher-order Strehl ratio presented a reduction of 0.03 (from 0.25 to 0.22) (P = .001). The following consistent linear predictive model was obtained: corneal HOA induction = 1.474 - 0.032 × SE - 0.225 × OZ, where OZ is the optical zone (R(2) = 0.49, adjusted R(2) = 0.48, P < .001). The corneal HOAs and the higher-order Strehl ratios deteriorated after moderate and high myopic ablations. The worsening in corneal aberrations and optical quality were related to the magnitude of the intended correction and did not affect high-contrast visual performance. The OZ was the only modifiable parameter capable to restrain the optical quality loss. The author has no financial or proprietary interest in any material or method mentioned. Copyright © 2015 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  8. [Imaging anatomy of cranial nerves].

    PubMed

    Hermier, M; Leal, P R L; Salaris, S F; Froment, J-C; Sindou, M

    2009-04-01

    Knowledge of the anatomy of the cranial nerves is mandatory for optimal radiological exploration and interpretation of the images in normal and pathological conditions. CT is the method of choice for the study of the skull base and its foramina. MRI explores the cranial nerves and their vascular relationships precisely. Because of their small size, it is essential to obtain images with high spatial resolution. The MRI sequences optimize contrast between nerves and surrounding structures (cerebrospinal fluid, fat, bone structures and vessels). This chapter discusses the radiological anatomy of the cranial nerves.

  9. Transient delayed facial nerve palsy after inferior alveolar nerve block anesthesia.

    PubMed

    Tzermpos, Fotios H; Cocos, Alina; Kleftogiannis, Matthaios; Zarakas, Marissa; Iatrou, Ioannis

    2012-01-01

    Facial nerve palsy, as a complication of an inferior alveolar nerve block anesthesia, is a rarely reported incident. Based on the time elapsed, from the moment of the injection to the onset of the symptoms, the paralysis could be either immediate or delayed. The purpose of this article is to report a case of delayed facial palsy as a result of inferior alveolar nerve block, which occurred 24 hours after the anesthetic administration and subsided in about 8 weeks. The pathogenesis, treatment, and results of an 8-week follow-up for a 20-year-old patient referred to a private maxillofacial clinic are presented and discussed. The patient's previous medical history was unremarkable. On clinical examination the patient exhibited generalized weakness of the left side of her face with a flat and expressionless appearance, and she was unable to close her left eye. One day before the onset of the symptoms, the patient had visited her dentist for a routine restorative procedure on the lower left first molar and an inferior alveolar block anesthesia was administered. The patient's medical history, clinical appearance, and complete examinations led to the diagnosis of delayed facial nerve palsy. Although neurologic occurrences are rare, dentists should keep in mind that certain dental procedures, such as inferior alveolar block anesthesia, could initiate facial nerve palsy. Attention should be paid during the administration of the anesthetic solution.

  10. Inferior alveolar nerve block: Alternative technique

    PubMed Central

    Thangavelu, K.; Kannan, R.; Kumar, N. Senthil

    2012-01-01

    Background: Inferior alveolar nerve block (IANB) is a technique of dental anesthesia, used to produce anesthesia of the mandibular teeth, gingivae of the mandible and lower lip. The conventional IANB is the most commonly used the nerve block technique for achieving local anesthesia for mandibular surgical procedures. In certain cases, however, this nerve block fails, even when performed by the most experienced clinician. Therefore, it would be advantageous to find an alternative simple technique. Aim and Objective: The objective of this study is to find an alternative inferior alveolar nerve block that has a higher success rate than other routine techniques. To this purpose, a simple painless inferior alveolar nerve block was designed to anesthetize the inferior alveolar nerve. Materials and Methods: This study was conducted in Oral surgery department of Vinayaka Mission's dental college Salem from May 2009 to May 2011. Five hundred patients between the age of 20 years and 65 years who required extraction of teeth in mandible were included in the study. Out of 500 patients 270 were males and 230 were females. The effectiveness of the IANB was evaluated by using a sharp dental explorer in the regions innervated by the inferior alveolar, lingual, and buccal nerves after 3, 5, and 7 min, respectively. Conclusion: This study concludes that inferior alveolar nerve block is an appropriate alternative nerve block to anesthetize inferior alveolar nerve due to its several advantages. PMID:25885503

  11. Axillary nerve injury associated with sports.

    PubMed

    Lee, Sangkook; Saetia, Kriangsak; Saha, Suparna; Kline, David G; Kim, Daniel H

    2011-11-01

    The aim of this retrospective study was to present and investigate axillary nerve injuries associated with sports. This study retrospectively reviewed 26 axillary nerve injuries associated with sports between the years 1985 and 2010. Preoperative status of the axillary nerve was evaluated by using the Louisiana State University Health Science Center (LSUHSC) grading system published by the senior authors. Intraoperative nerve action potential recordings were performed to check nerve conduction and assess the possibility of resection. Neurolysis, suture, and nerve grafts were used for the surgical repair of the injured nerves. In 9 patients with partial loss of function and 3 with complete loss, neurolysis based on nerve action potential recordings was the primary treatment. Two patients with complete loss of function were treated with resection and suturing and 12 with resection and nerve grafting. The minimum follow-up period was 16 months (mean 20 months). The injuries were associated with the following sports: skiing (12 cases), football (5), rugby (2), baseball (2), ice hockey (2), soccer (1), weightlifting (1), and wrestling (1). Functional recovery was excellent. Neurolysis was performed in 9 cases, resulting in an average functional recovery of LSUHSC Grade 4.2. Recovery with graft repairs averaged LSUHSC Grade 3 or better in 11 of 12 cases Surgical repair can restore useful deltoid function in patients with sports-associated axillary nerve injuries, even in cases of severe stretch-contusion injury.

  12. Recovery of the sub-basal nerve plexus and superficial nerve terminals after corneal epithelial injury in mice.

    PubMed

    Downie, Laura E; Naranjo Golborne, Cecilia; Chen, Merry; Ho, Ngoc; Hoac, Cam; Liyanapathirana, Dasun; Luo, Carol; Wu, Ruo Bing; Chinnery, Holly R

    2018-06-01

    Our aim was to compare regeneration of the sub-basal nerve plexus (SBNP) and superficial nerve terminals (SNT) following corneal epithelial injury. We also sought to compare agreement when quantifying nerve parameters using different image analysis techniques. Anesthetized, female C57BL/6 mice received central 1-mm corneal epithelial abrasions. Four-weeks post-injury, eyes were enucleated and processed for PGP9.5 to visualize the corneal nerves using wholemount immunofluorescence staining and confocal microscopy. The percentage area of the SBNP and SNT were quantified using: ImageJ automated thresholds, ImageJ manual thresholds and manual tracings in NeuronJ. Nerve sum length was quantified using NeuronJ and Imaris. Agreement between methods was considered with Bland-Altman analyses. Four-weeks post-injury, the sum length of nerve fibers in the SBNP, but not the SNT, was reduced compared with naïve eyes. In the periphery, but not central cornea, of both naïve and injured eyes, nerve fiber lengths in the SBNP and SNT were strongly correlated. For quantifying SBNP nerve axon area, all image analysis methods were highly correlated. In the SNT, there was poor correlation between manual methods and auto-thresholding, with a trend towards underestimating nerve fiber area using auto-thresholding when higher proportions of nerve fibers were present. In conclusion, four weeks after superficial corneal injury, there is differential recovery of epithelial nerve axons; SBNP sum length is reduced, however the sum length of SNTs is similar to naïve eyes. Care should be taken when selecting image analysis methods to compare nerve parameters in different depths of the corneal epithelium due to differences in background autofluorescence. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. The morphological substrate for Renal Denervation: Nerve distribution patterns and parasympathetic nerves. A post-mortem histological study.

    PubMed

    van Amsterdam, Wouter A C; Blankestijn, Peter J; Goldschmeding, Roel; Bleys, Ronald L A W

    2016-03-01

    Renal Denervation as a possible treatment for hypertension has been studied extensively, but knowledge on the distribution of nerves surrounding the renal artery is still incomplete. While sympathetic and sensory nerves have been demonstrated, there is no mention of the presence of parasympathetic nerve fibers. To provide a description of the distribution patterns of the renal nerves in man, and, in addition, provide a detailed representation of the relative contribution of the sympathetic, parasympathetic and afferent divisions of the autonomic nervous system. Renal arteries of human cadavers were each divided into four longitudinal segments and immunohistochemically stained with specific markers for afferent, parasympathetic and sympathetic nerves. Nerve fibers were semi-automatically quantified by computerized image analysis, and expressed as cross-sectional area relative to the distance to the lumen. A total of 3372 nerve segments were identified in 8 arteries of 7 cadavers. Sympathetic, parasympathetic and afferent nerves contributed for 73.5% (95% CI: 65.4-81.5%), 17.9% (10.7-25.1%) and 8.7% (5.0-12.3%) of the total cross-sectional nerve area, respectively. Nerves are closer to the lumen in more distal segments and larger bundles that presumably innervate the kidney lie at 1-3.5mm distance from the lumen. The tissue-penetration depth of the ablation required to destroy 50% of the nerve fibers is 2.37 mm in the proximal segment and 1.78 mm in the most distal segments. Sympathetic, parasympathetic and afferent nerves exist in the vicinity of the renal artery. The results warrant further investigation of the role of the parasympathetic nervous system on renal physiology, and may contribute to refinement of the procedure by focusing the ablation on the most distal segment. Copyright © 2015 Elsevier GmbH. All rights reserved.

  14. Combined KHFAC+DC nerve block without onset or reduced nerve conductivity after block

    PubMed Central

    Franke, Manfred; Vrabec, Tina; Wainright, Jesse; Bhadra, Niloy; Bhadra, Narendra; Kilgore, Kevin

    2017-01-01

    Background Kilohertz Frequency Alternating Current waveforms (KHFAC) have been shown to provide peripheral nerve conductivity block in many acute and chronic animal models. KHFAC nerve block could be used to address multiple disorders caused by neural over-activity, including blocking pain and spasticity. However, one drawback of KHFAC block is a transient activation of nerve fibers during the initiation of the nerve block, called the onset response. The objective of this study is to evaluate the feasibility of using charge balanced direct current (CBDC) waveforms to temporarily block motor nerve conductivity distally to the KHFAC electrodes to mitigate the block onset-response. Methods A total of eight animals were used in this study. A set of four animals were used to assess feasibility and reproducibility of a combined KHFAC+CBDC block. A following randomized study, conducted on a second set of four animals, compared the onset response resulting from KHFAC alone and combined KHFAC+CBDC waveforms. To quantify the onset, peak forces and the force-time integral were measured during KHFAC block initiation. Nerve conductivity was monitored throughout the study by comparing muscle twitch forces evoked by supra-maximal stimulation proximal and distal to the block electrodes. Each animal of the randomized study received at least 300 seconds (range: 318 to 1563s) of cumulative DC to investigate the impact of combined KHFAC+CBDC on nerve viability. Results The peak onset force was reduced significantly from 20.73 N (range: 18.6–26.5 N) with KHFAC alone to 0.45 N (range: 0.2–0.7 N) with the combined CBDC and KHFAC block waveform (p<0.001). The area under the force curve was reduced from 6.8 Ns (range: 3.5–21.9 Ns) to 0.54 Ns (range: 0.18–0.86Ns) (p<0.01). No change in nerve conductivity was observed after application of the combined KHFAC+CBDC block relative to KHFAC waveforms. Conclusion The distal application of CBDC can significantly reduce or even completely

  15. Low-Order Aberrations in Band-limited Lyot Coronagraphs

    NASA Astrophysics Data System (ADS)

    Sivaramakrishnan, Anand; Soummer, Rémi; Sivaramakrishnan, Allic V.; Lloyd, James P.; Oppenheimer, Ben R.; Makidon, Russell B.

    2005-12-01

    We study the way Lyot coronagraphs with unapodized entrance pupils respond to small, low-order phase aberrations. This study is applicable to ground-based adaptive optics coronagraphs operating at 90% and higher Strehl ratios, as well as to some space-based coronagraphs with intrinsically higher Strehl ratio imaging. We utilize a second-order expansion of the monochromatic point-spread function (written as a power spectrum of a power series in the phase aberration over clear aperture) to derive analytical expressions for the response of a ``band-limited'' Lyot coronagraph (BLC) to small, low-order, phase aberrations. The BLC possesses a focal plane mask with an occulting spot whose opacity profile is a spatially band-limited function rather than a hard-edged, opaque disk. The BLC is, to first order, insensitive to tilt and astigmatism. Undersizing the stop in the reimaged pupil plane (the Lyot plane) following the focal plane mask can alleviate second-order effects of astigmatism, at the expense of system throughput and angular resolution. The optimal degree of such undersizing depends on individual instrument designs and goals. Our analytical work engenders physical insight and complements existing numerical work on this subject. Our methods can be extended to treat the passage of higher order aberrations through band-limited Lyot coronagraphs by using our polynomial decomposition or an analogous Fourier approach.

  16. Immediate Nerve Transfer for Treatment of Peroneal Nerve Palsy Secondary to an Intraneural Ganglion: Case Report and Review.

    PubMed

    Ratanshi, Imran; Clark, Tod A; Giuffre, Jennifer L

    2018-05-01

    Intraneural ganglion cysts, which occur within the common peroneal nerve, are a rare cause of foot drop. The current standard of treatment for intraneural ganglion cysts involving the common peroneal nerve involves (1) cyst decompression and (2) ligation of the articular nerve branch to prevent recurrence. Nerve transfers are a time-dependent strategy for recovering ankle dorsiflexion in cases of high peroneal nerve palsy; however, this modality has not been performed for intraneural ganglion cysts involving the common peroneal nerve. We present a case of common peroneal nerve palsy secondary to an intraneural ganglion cyst occurring in a 74-year-old female. The patient presented with a 5-month history of pain in the right common peroneal nerve distribution and foot drop. The patient underwent simultaneous cyst decompression, articular nerve branch ligation, and nerve transfer of the motor branch to flexor hallucis longus to a motor branch of anterior tibialis muscle. At final follow-up, the patient demonstrated complete (M4+) return of ankle dorsiflexion, no pain, no evidence of recurrence and was able to bear weight without the need for orthotic support. Given the minimal donor site morbidity and recovery of ankle dorsiflexion, this report underscores the importance of considering early nerve transfers in cases of high peroneal neuropathy due to an intraneural ganglion cyst.

  17. [Regional nerve block in facial surgery].

    PubMed

    Gramkow, Christina; Sørensen, Jesper

    2008-02-11

    Regional nerve blocking techniques offer a suitable alternative to local infiltration anaesthesia for facial soft tissue-surgery. Moreover, they present several advantages over general anaesthesia, including smoother recovery, fewer side effects, residual analgesia into the postoperative period, earlier discharge from the recovery room and reduced costs. The branches of the trigeminal nerve and the sensory nerves originating from the upper cervical plexus can be targeted at several anatomical locations. We summarize current knowledge on facial nerve block techniques and recommend ten nerve blocks providing efficient anaesthesia for the entire head and upper-neck region.

  18. Efficacy of predictive wavefront control for compensating aero-optical aberrations

    NASA Astrophysics Data System (ADS)

    Goorskey, David J.; Schmidt, Jason; Whiteley, Matthew R.

    2013-07-01

    Imaging and laser beam propagation from airborne platforms are degraded by dynamic aberrations due to air flow around the aircraft, aero-mechanical distortions and jitter, and free atmospheric turbulence. For certain applications, like dim-object imaging, free-space optical communications, and laser weapons, adaptive optics (AO) is necessary to compensate for the aberrations in real time. Aero-optical flow is a particularly interesting source of aberrations whose flowing structures can be exploited by adaptive and predictive AO controllers, thereby realizing significant performance gains. We analyze dynamic aero-optical wavefronts to determine the pointing angles at which predictive wavefront control is more effective than conventional, fixed-gain, linear-filter control. It was found that properties of the spatial decompositions and temporal statistics of the wavefronts are directly traceable to specific features in the air flow. Furthermore, the aero-optical wavefront aberrations at the side- and aft-looking angles were the most severe, but they also benefited the most from predictive AO.

  19. In vivo targeted peripheral nerve imaging with a nerve-specific nanoscale magnetic resonance probe.

    PubMed

    Zheng, Linfeng; Li, Kangan; Han, Yuedong; Wei, Wei; Zheng, Sujuan; Zhang, Guixiang

    2014-11-01

    Neuroimaging plays a pivotal role in clinical practice. Currently, computed tomography (CT), magnetic resonance imaging (MRI), ultrasonography, and positron emission tomography (PET) are applied in the clinical setting as neuroimaging modalities. There is no optimal imaging modality for clinical peripheral nerve imaging even though fluorescence/bioluminescence imaging has been used for preclinical studies on the nervous system. Some studies have shown that molecular and cellular MRI (MCMRI) can be used to visualize and image the cellular and molecular level of the nervous system. Other studies revealed that there are different pathological/molecular changes in the proximal and distal sites after peripheral nerve injury (PNI). Therefore, we hypothesized that in vivo peripheral nerve targets can be imaged using MCMRI with specific MRI probes. Specific probes should have higher penetrability for the blood-nerve barrier (BNB) in vivo. Here, a functional nanometre MRI probe that is based on nerve-specific proteins as targets, specifically, using a molecular antibody (mAb) fragment conjugated to iron nanoparticles as an MRI probe, was constructed for further study. The MRI probe allows for imaging the peripheral nerve targets in vivo. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Peripheral nerve conduits: technology update

    PubMed Central

    Arslantunali, D; Dursun, T; Yucel, D; Hasirci, N; Hasirci, V

    2014-01-01

    Peripheral nerve injury is a worldwide clinical problem which could lead to loss of neuronal communication along sensory and motor nerves between the central nervous system (CNS) and the peripheral organs and impairs the quality of life of a patient. The primary requirement for the treatment of complete lesions is a tension-free, end-to-end repair. When end-to-end repair is not possible, peripheral nerve grafts or nerve conduits are used. The limited availability of autografts, and drawbacks of the allografts and xenografts like immunological reactions, forced the researchers to investigate and develop alternative approaches, mainly nerve conduits. In this review, recent information on the various types of conduit materials (made of biological and synthetic polymers) and designs (tubular, fibrous, and matrix type) are being presented. PMID:25489251

  1. Transsphenoidal and infralabyrinthine approach of the petrous apex cholesterol granuloma.

    PubMed

    Bruchhage, Karl-Ludwig; Wollenberg, Barbara; Leichtle, Anke

    2017-07-01

    Space-demanding or destructive changes in the petrous bone are often challenging differential diagnosis. Cholesterol granulomas of the petrous apex can clinically present in a combination of hearing loss, vertigo, tinnitus, chronic cephalgia, impairment of facial nerve function, neuralgic pain of the nervus trigeminus, or manifest diplopia by the nerve palsy of the nervus abducens. CT-morphologically cholesterol granulomas appear as soft-tissue density masses, which may display a discrete rim after intravenous administration of a contrast agent. The MRI, T1 as well as T2-weighted images show a strong signal in the area of the lesion. Depending on the individual anatomical conditions, the surgical access must be carefully chosen between transsphenoidal, transtemporal, infracochlear/-labyrinthine, or translabyrinthine. Here, we present the transsphenoidal and translabyrinthine access for the excision of cholesterol granulomas of the petrous apex. The different accesses are compared using a neuro-navigation-supported surgical technique with respect to its complications, drainage possibilities, outcomes, and recurrence of symptoms.

  2. Nerve Injuries in Athletes.

    ERIC Educational Resources Information Center

    Collins, Kathryn; And Others

    1988-01-01

    Over a two-year period this study evaluated the condition of 65 athletes with nerve injuries. These injuries represent the spectrum of nerve injuries likely to be encountered in sports medicine clinics. (Author/MT)

  3. Measurement of specimen-induced aberrations of biological samples using phase stepping interferometry.

    PubMed

    Schwertner, M; Booth, M J; Neil, M A A; Wilson, T

    2004-01-01

    Confocal or multiphoton microscopes, which deliver optical sections and three-dimensional (3D) images of thick specimens, are widely used in biology. These techniques, however, are sensitive to aberrations that may originate from the refractive index structure of the specimen itself. The aberrations cause reduced signal intensity and the 3D resolution of the instrument is compromised. It has been suggested to correct for aberrations in confocal microscopes using adaptive optics. In order to define the design specifications for such adaptive optics systems, one has to know the amount of aberrations present for typical applications such as with biological samples. We have built a phase stepping interferometer microscope that directly measures the aberration of the wavefront. The modal content of the wavefront is extracted by employing Zernike mode decomposition. Results for typical biological specimens are presented. It was found for all samples investigated that higher order Zernike modes give only a small contribution to the overall aberration. Therefore, these higher order modes can be neglected in future adaptive optics sensing and correction schemes implemented into confocal or multiphoton microscopes, leading to more efficient designs.

  4. Facial Nerve Paralysis due to a Pleomorphic Adenoma with the Imaging Characteristics of a Facial Nerve Schwannoma

    PubMed Central

    Nader, Marc-Elie; Bell, Diana; Sturgis, Erich M.; Ginsberg, Lawrence E.; Gidley, Paul W.

    2014-01-01

    Background Facial nerve paralysis in a patient with a salivary gland mass usually denotes malignancy. However, facial paralysis can also be caused by benign salivary gland tumors. Methods We present a case of facial nerve paralysis due to a benign salivary gland tumor that had the imaging characteristics of an intraparotid facial nerve schwannoma. Results The patient presented to our clinic 4 years after the onset of facial nerve paralysis initially diagnosed as Bell palsy. Computed tomography demonstrated filling and erosion of the stylomastoid foramen with a mass on the facial nerve. Postoperative histopathology showed the presence of a pleomorphic adenoma. Facial paralysis was thought to be caused by extrinsic nerve compression. Conclusions This case illustrates the difficulty of accurate preoperative diagnosis of a parotid gland mass and reinforces the concept that facial nerve paralysis in the context of salivary gland tumors may not always indicate malignancy. PMID:25083397

  5. Facial Nerve Paralysis due to a Pleomorphic Adenoma with the Imaging Characteristics of a Facial Nerve Schwannoma.

    PubMed

    Nader, Marc-Elie; Bell, Diana; Sturgis, Erich M; Ginsberg, Lawrence E; Gidley, Paul W

    2014-08-01

    Background Facial nerve paralysis in a patient with a salivary gland mass usually denotes malignancy. However, facial paralysis can also be caused by benign salivary gland tumors. Methods We present a case of facial nerve paralysis due to a benign salivary gland tumor that had the imaging characteristics of an intraparotid facial nerve schwannoma. Results The patient presented to our clinic 4 years after the onset of facial nerve paralysis initially diagnosed as Bell palsy. Computed tomography demonstrated filling and erosion of the stylomastoid foramen with a mass on the facial nerve. Postoperative histopathology showed the presence of a pleomorphic adenoma. Facial paralysis was thought to be caused by extrinsic nerve compression. Conclusions This case illustrates the difficulty of accurate preoperative diagnosis of a parotid gland mass and reinforces the concept that facial nerve paralysis in the context of salivary gland tumors may not always indicate malignancy.

  6. Study of the performance of image restoration under different wavefront aberrations

    NASA Astrophysics Data System (ADS)

    Wang, Xinqiu; Hu, Xinqi

    2016-10-01

    Image restoration is an effective way to improve the quality of images degraded by wave-front aberrations. If the wave-front aberration is too large, the performance of the image restoration will not be good. In this paper, the relationship between the performance of image restoration and the degree of wave-front aberrations is studied. A set of different wave-front aberrations is constructed by Zernike polynomials, and the corresponding PSF under white-light illumination is calculated. A set of blurred images is then obtained through convolution methods. Next we recover the images with the regularized Richardson-Lucy algorithm and use the RMS of the original image and the homologous deblurred image to evaluate the quality of restoration. Consequently, we determine the range of wave-front errors in which the recovered images are acceptable.

  7. Collision tumor of the facial nerve: a synchronous seventh nerve schwannoma and neurofibroma.

    PubMed

    Gross, Brian C; Carlson, Matthew L; Driscoll, Colin L; Moore, Eric J

    2012-10-01

    To report a novel case of a collision tumor involving an intraparotid neurofibroma and a mastoid segment facial nerve schwannoma. Clinical capsule report. Tertiary academic referral center. A 29-year-old woman with a 2-year history of an asymptomatic enlarging left infraauricular mass and normal FN function presented to a tertiary care referral center. Computed tomography and magnetic resonance imaging demonstrated a cystic lesion in the deep portion of the parotid gland extending into the stylomastoid foramen. The patient underwent superficial parotidectomy, and a cystic parotid mass was found to be intrinsic to the intraparotid facial nerve. A portion of the mass was biopsied, and intraoperative frozen section pathology was consistent with a neurofibroma. A mastoidectomy with FN decompression was then performed until a normal-appearing segment was identified just proximal to the second genu. After biopsy, proximal facial nerve stimulation failed to elicit evoked motor potentials, and en bloc resection was performed. Final pathology demonstrated a schwannoma involving the mastoid segment and a neurofibroma involving the proximal intraparotid facial nerve. We report the first case of a facial nerve collision tumor involving an intraparotid neurofibroma and a mastoid segment facial nerve schwannoma. Benign FN sheath tumors of the parotid gland are rare but should be considered in the differential diagnosis of a parotid mass.

  8. Reconstruction of facial nerve injuries in children.

    PubMed

    Fattah, Adel; Borschel, Gregory H; Zuker, Ron M

    2011-05-01

    Facial nerve trauma is uncommon in children, and many spontaneously recover some function; nonetheless, loss of facial nerve activity leads to functional impairment of ocular and oral sphincters and nasal orifice. In many cases, the impediment posed by facial asymmetry and reduced mimetic function more significantly affects the child's psychosocial interactions. As such, reconstruction of the facial nerve affords great benefits in quality of life. The therapeutic strategy is dependent on numerous factors, including the cause of facial nerve injury, the deficit, the prognosis for recovery, and the time elapsed since the injury. The options for treatment include a diverse range of surgical techniques including static lifts and slings, nerve repairs, nerve grafts and nerve transfers, regional, and microvascular free muscle transfer. We review our strategies for addressing facial nerve injuries in children.

  9. The role of ethnic identity, self-concept, and aberrant salience in psychotic-like experiences.

    PubMed

    Cicero, David C; Cohn, Jonathan R

    2018-01-01

    Social-cognitive models of psychosis suggest that aberrant salience and self-concept clarity are related to the development and maintenance of psychoticlike experiences (PLEs). People with high aberrant salience but low self-concept clarity tend to have the highest levels of PLEs. Ethnic identity may also be related to PLEs. The current research aimed to (a) replicate the interaction between aberrant salience and self-concept clarity in their association with PLEs in an ethnically diverse sample, (b) examine whether ethnic identity and aberrant salience interact in their association with PLEs, and (c) determine if self-concept clarity and ethnic identity independently interact with aberrant salience in their association with PLEs. An ethnically diverse group of undergraduates (n = 663) completed self-report measures of aberrant salience, self-concept clarity, ethnic identity, and PLEs. There was an interaction between aberrant salience and self-concept clarity such that people with high levels of aberrant salience and low levels of self-concept clarity had the highest levels of PLEs. Similarly, there was an interaction between aberrant salience and ethnic identity such that people with high aberrant salience but low ethnic identity had the highest PLEs. These interactions independently contributed to explaining variance in PLEs. This interaction was present for the Exploration but not Commitment subscales of ethnic identity. These results suggest that, in addition to low self-concept clarity, low ethnic identity may be a risk factor for the development of psychosis. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  10. The Cranial Nerve Skywalk: A 3D Tutorial of Cranial Nerves in a Virtual Platform

    ERIC Educational Resources Information Center

    Richardson-Hatcher, April; Hazzard, Matthew; Ramirez-Yanez, German

    2014-01-01

    Visualization of the complex courses of the cranial nerves by students in the health-related professions is challenging through either diagrams in books or plastic models in the gross laboratory. Furthermore, dissection of the cranial nerves in the gross laboratory is an extremely meticulous task. Teaching and learning the cranial nerve pathways…

  11. Raman spectroscopy of non-penetrating peripheral nerve damage in swine: a tool for spectral pathology of nerves

    NASA Astrophysics Data System (ADS)

    Cilwa, Katherine E.; Slaughter, Tiffani; Elster, Eric A.; Forsberg, Jonathan A.; Crane, Nicole J.

    2015-03-01

    Over 30% of combat injuries involve peripheral nerve injury compared to only 3% in civilian trauma. In fact, nerve dysfunction is the second leading cause of long-term disability in injured service members and is present in 37% of upper limb injuries with disability. Identification and assessment of non-penetrating nerve injury in trauma patients could improve outcome and aid in therapeutic monitoring. We report the use of Raman spectroscopy as a noninvasive, non-destructive method for detection of nerve degeneration in intact nerves due to non-penetrating trauma. Nerve trauma was induced via compression and ischemia/reperfusion injury using a combat relevant swine tourniquet model (>3 hours ischemia). Control animals did not undergo compression/ischemia. Seven days post-operatively, sciatic and femoral nerves were harvested and fixed in formalin. Raman spectra of intact, peripheral nerves were collected using a fiber-optic probe with 3 mm diameter spot size and 785 nm excitation. Data was preprocessed, including fluorescence background subtraction, and Raman spectroscopic metrics were determined using custom peak fitting MATLAB scripts. The abilities of bivariate and multivariate analysis methods to predict tissue state based on Raman spectroscopic metrics are compared. Injured nerves exhibited changes in Raman metrics indicative of 45% decreased myelin content and structural damage (p<<0.01). Axonal and myelin degeneration, cell death and digestion, and inflammation of nerve tissue samples were confirmed via histology. This study demonstrates the non-invasive ability of Raman spectroscopy to detect nerve degeneration associated with non-penetrating injury, relevant to neurapraxic and axonotmetic injuries; future experiments will further explore the clinical utility of Raman spectroscopy to recognize neural injury.

  12. Side Effects: Nerve Problems (Peripheral Neuropathy)

    Cancer.gov

    Nerve problems, such as peripheral neuropathy, can be caused by cancer treatment. Learn about signs and symptoms of nerve changes. Find out how to prevent or manage nerve problems during cancer treatment.

  13. VAGUS NERVE STIMULATION REGULATES HEMOSTASIS IN SWINE

    PubMed Central

    Czura, Christopher J.; Schultz, Arthur; Kaipel, Martin; Khadem, Anna; Huston, Jared M.; Pavlov, Valentin A.; Redl, Heinz; Tracey, Kevin J.

    2010-01-01

    The central nervous system regulates peripheral immune responses via the vagus nerve, the primary neural component of the cholinergic anti-inflammatory pathway. Electrical stimulation of the vagus nerve suppresses pro-inflammatory cytokine release in response to endotoxin, I/R injury, and hypovolemic shock and protects against lethal hypotension. To determine the effect of vagus nerve stimulation on coagulation pathways, anesthetized pigs were subjected to partial ear resection before and after electrical vagus nerve stimulation. We observed that electrical vagus nerve stimulation significantly decreased bleeding time (pre–electrical vagus nerve stimulation = 1033 ± 210 s versus post–electrical vagus nerve stimulation = 585 ± 111 s; P < 0.05) and total blood loss (pre–electrical vagus nerve stimulation = 48.4 ± 6.8 mL versus post–electrical vagus nerve stimulation = 26.3 ± 6.7 mL; P < 0.05). Reduced bleeding time after vagus nerve stimulation was independent of changes in heart rate or blood pressure and correlated with increased thrombin/antithrombin III complex generation in shed blood. These data indicate that electrical stimulation of the vagus nerve attenuates peripheral hemorrhage in a porcine model of soft tissue injury and that this protective effect is associated with increased coagulation factor activity. PMID:19953009

  14. Nerve growth factor released from a novel PLGA nerve conduit can improve axon growth

    NASA Astrophysics Data System (ADS)

    Lin, Keng-Min; Shea, Jill; Gale, Bruce K.; Sant, Himanshu; Larrabee, Patti; Agarwal, Jay

    2016-04-01

    Nerve injury can occur due to penetrating wounds, compression, traumatic stretch, and cold exposure. Despite prompt repair, outcomes are dismal. In an attempt to help resolve this challenge, in this work, a poly-lactic-co-glycolic acid (PLGA) nerve conduit with associated biodegradable drug reservoir was designed, fabricated, and tested. Unlike current nerve conduits, this device is capable of fitting various clinical scenarios by delivering different drugs without reengineering the whole system. To demonstrate the potential of this device for nerve repair, a series of experiments were performed using nerve growth factor (NGF). First, an NGF dosage curve was developed to determine the minimum NGF concentration for optimal axonal outgrowth on chick dorsal root ganglia (DRG) cells. Next, PLGA devices loaded with NGF were evaluated for sustained drug release and axon growth enhancement with the released drug. A 20 d in vitro release test was conducted and the nerve conduit showed the ability to meet and maintain the minimum NGF requirement determined previously. Bioactivity assays of the released NGF showed that drug released from the device between the 15th and 20th day could still promote axon growth (76.6-95.7 μm) in chick DRG cells, which is in the range of maximum growth. These novel drug delivery conduits show the ability to deliver NGF at a dosage that efficiently promotes ex vivo axon growth and have the potential for in vivo application to help bridge peripheral nerve gaps.

  15. Aberrant and multiaberrant (rogue) cells in peripheral lymphocytes of Hodgkin's lymphoma patients after chemotherapy.

    PubMed

    Ryabchenko, Nikolay I; Nasonova, Valentina A; Fesenko, Eleonora V; Kondrashova, Tatiana V; Antoschina, Margarita M; Pavlov, Vyacheslav V; Ryabikina, Natalya V

    2006-10-10

    We analyzed spontaneous chromosome lesions in peripheral lymphocytes cultured from Hodgkin's lymphoma (HL) patients before and after cytostatic chemotherapy. The mean aberration frequency was significantly higher in HL patients after chemotherapy (7.20+/-0.58 per 100 metaphases) than in non-treated HL patients (4.80+/-0.54), and in non-treated patients than in healthy subjects (2.12+/-0.13). In lymphocytes of HL patients, who received chemotherapy, we found, in addition to ordinary aberrant cells, a large number of multiaberrant (or rogue) cells, i.e. metaphases carrying multiple (at least four) chromosome-type exchange aberrations. Rogue cells were found in 15 out of 18 chemotherapeutically treated HL patients (in total, 60 rogue cells per 5,568 scored cells), whereas in 30 non-treated patients only 1 rogue cell was found (per 4,988 scored cells). No correlation was found between the yield of rogue cells and the aberration frequency in ordinary aberrant cells. Aberration spectra (ratios of chromatid- to chromosome-type aberrations and of breaks to exchanges) were essentially different in ordinary aberrant and multiaberrant cells. These data, as well as analysis of cellular distributions of aberrations, implied independent induction of chromosome damage in ordinary aberrant and rogue cells. Analysis of aberration patterns in diploid and polyploid rogue metaphases belonging to the first, second, and third in vitro division indicated that rogue cells could be formed both in vivo and in vitro, and could survive at least two rounds of in vitro replication, given blocked chromosome segregation. These results suggested that formation of rogue cells, unlike ordinary aberrant cells, was triggered by events other than direct DNA and/or chromosome lesions. A hypothesis regarding disrupted apoptosis as a candidate mechanism for rogue cell formation seems to be most suitable for interpretation of our data. Cultured lymphocytes of chemotherapeutically treated HL patients may

  16. Hartmann characterization of the PEEM-3 aberration-corrected X-ray photoemission electron microscope.

    PubMed

    Scholl, A; Marcus, M A; Doran, A; Nasiatka, J R; Young, A T; MacDowell, A A; Streubel, R; Kent, N; Feng, J; Wan, W; Padmore, H A

    2018-05-01

    Aberration correction by an electron mirror dramatically improves the spatial resolution and transmission of photoemission electron microscopes. We will review the performance of the recently installed aberration corrector of the X-ray Photoemission Electron Microscope PEEM-3 and show a large improvement in the efficiency of the electron optics. Hartmann testing is introduced as a quantitative method to measure the geometrical aberrations of a cathode lens electron microscope. We find that aberration correction leads to an order of magnitude reduction of the spherical aberrations, suggesting that a spatial resolution of below 100 nm is possible at 100% transmission of the optics when using x-rays. We demonstrate this improved performance by imaging test patterns employing element and magnetic contrast. Published by Elsevier B.V.

  17. Spherical aberration correction with threefold symmetric line currents.

    PubMed

    Hoque, Shahedul; Ito, Hiroyuki; Nishi, Ryuji; Takaoka, Akio; Munro, Eric

    2016-02-01

    It has been shown that N-fold symmetric line current (henceforth denoted as N-SYLC) produces 2N-pole magnetic fields. In this paper, a threefold symmetric line current (N3-SYLC in short) is proposed for correcting 3rd order spherical aberration of round lenses. N3-SYLC can be realized without using magnetic materials, which makes it free of the problems of hysteresis, inhomogeneity and saturation. We investigate theoretically the basic properties of an N3-SYLC configuration which can in principle be realized by simple wires. By optimizing the parameters of a system with beam energy of 5.5keV, the required excitation current for correcting 3rd order spherical aberration coefficient of 400 mm is less than 1AT, and the residual higher order aberrations can be kept sufficiently small to obtain beam size of less than 1 nm for initial slopes up to 5 mrad. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Hydrogel derived from porcine decellularized nerve tissue as a promising biomaterial for repairing peripheral nerve defects.

    PubMed

    Lin, Tao; Liu, Sheng; Chen, Shihao; Qiu, Shuai; Rao, Zilong; Liu, Jianghui; Zhu, Shuang; Yan, Liwei; Mao, Haiquan; Zhu, Qingtang; Quan, Daping; Liu, Xiaolin

    2018-06-01

    Decellularized matrix hydrogels derived from tissues or organs have been used for tissue repair due to their biocompatibility, tunability, and tissue-specific extracellular matrix (ECM) components. However, the preparation of decellularized peripheral nerve matrix hydrogels and their use to repair nerve defects have not been reported. Here, we developed a hydrogel from porcine decellularized nerve matrix (pDNM-G), which was confirmed to have minimal DNA content and retain collagen and glycosaminoglycans content, thereby allowing gelatinization. The pDNM-G exhibited a nanofibrous structure similar to that of natural ECM, and a ∼280-Pa storage modulus at 10 mg/mL similar to that of native neural tissues. Western blot and liquid chromatography tandem mass spectrometry analysis revealed that the pDNM-G consisted mostly of ECM proteins and contained primary ECM-related proteins, including fibronectin and collagen I and IV). In vitro experiments showed that pDNM-G supported Schwann cell proliferation and preserved cell morphology. Additionally, in a 15-mm rat sciatic nerve defect model, pDNM-G was combined with electrospun poly(lactic-acid)-co-poly(trimethylene-carbonate)conduits to bridge the defect, which did not elicit an adverse immune response and promoted the activation of M2 macrophages associated with a constructive remodeling response. Morphological analyses and electrophysiological and functional examinations revealed that the regenerative outcomes achieved by pDNM-G were superior to those by empty conduits and closed to those using rat decellularized nerve matrix allograft scaffolds. These findings indicated that pDNM-G, with its preserved ECM composition and nanofibrous structure, represents a promising biomaterial for peripheral nerve regeneration. Decellularized nerve allografts have been widely used to treat peripheral nerve injury. However, given their limited availability and lack of bioactive factors, efforts have been made to improve the efficacy

  19. The BHVI-EyeMapper: Peripheral Refraction and Aberration Profiles

    PubMed Central

    Fedtke, Cathleen; Ehrmann, Klaus; Falk, Darrin; Bakaraju, Ravi C.; Holden, Brien A.

    2014-01-01

    ABSTRACT Purpose The aim of this article was to present the optical design of a new instrument (BHVI-EyeMapper, EM), which is dedicated to rapid peripheral wavefront measurements across the visual field for distance and near, and to compare the peripheral refraction and higher-order aberration profiles obtained in myopic eyes with and without accommodation. Methods Central and peripheral refractive errors (M, J180, and J45) and higher-order aberrations (C[3, 1], C[3, 3], and C[4, 0]) were measured in 26 myopic participants (mean [±SD] age, 20.9 [±2.0] years; mean [±SD] spherical equivalent, −3.00 [±0.90] diopters [D]) corrected for distance. Measurements were performed along the horizontal visual field with (−2.00 to −5.00 D) and without (+1.00 D fogging) accommodation. Changes as a function of accommodation were compared using tilt and curvature coefficients of peripheral refraction and aberration profiles. Results As accommodation increased, the relative peripheral refraction profiles of M and J180 became significantly (p < 0.05) more negative and the profile of M became significantly (p < 0.05) more asymmetric. No significant differences were found for the J45 profiles (p > 0.05). The peripheral aberration profiles of C[3, 1], C[3, 3], and C[4, 0] became significantly (p < 0.05) less asymmetric as accommodation increased, but no differences were found in the curvature. Conclusions The current study showed that significant changes in peripheral refraction and higher-order aberration profiles occurred during accommodation in myopic eyes. With its extended measurement capabilities, that is, permitting rapid peripheral refraction and higher-order aberration measurements up to visual field angles of ±50 degrees for distance and near (up to −5.00 D), the EM is a new advanced instrument that may provide additional insights in the ongoing quest to understand and monitor myopia development. PMID:25105690

  20. Recurrent laryngeal nerve landmarks during thyroidectomy.

    PubMed

    Ngo Nyeki, A-R; Njock, L-R; Miloundja, J; Evehe Vokwely, J-E; Bengono, G

    2015-11-01

    This study was designed to describe the various anatomical relations of the recurrent laryngeal nerve (RLN) during thyroid surgery in a Central African population. A prospective study was conducted between January 2012 and December 2012 in 5 otorhinolaryngology and head and neck surgery departments in Cameroon and Gabon. All patients undergoing total or subtotal thyroidectomy or loboisthmectomy with recurrent laryngeal nerve dissection, with no history of previous thyroid surgery, RLN dissection or tumour infiltration of the RLN, were included. Fifty-six patients were included, corresponding to 36 loboisthmectomies and 20 total or subtotal thyroidectomies. A total of 62 recurrent laryngeal nerves were identified: 32 on the right and 30 on the left. The course of the recurrent laryngeal nerve in relation to branches of the inferior thyroid artery (ITA) was retrovascular in 53.1% of cases on the right and 76.6% of cases on the left; transvascular in 15.6% of cases on the right and 13.4% of cases on the left. The course of the recurrent laryngeal nerve was modified by thyroid disease in 12.9% of cases. Six cases (9.7%) of extralaryngeal division of the recurrent laryngeal nerve were observed. No case of non-recurrent nerve was observed in this series. The anatomical relations of the recurrent laryngeal nerve with the inferior thyroid artery were very inconstant in this series and were predominantly retrovascular or transvascular in relation to the branches of the artery. The presence of extralaryngeal branches and modification of the course of the nerve by thyroid disease also introduced additional difficulties during recurrent laryngeal nerve dissection. The anatomical relations of the right recurrent laryngeal nerve in this African population differ from the classically described prevascular course. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  1. Micronuclei versus Chromosomal Aberrations Induced by X-Ray in Radiosensitive Mammalian Cells.

    PubMed

    Plamadeala, Cristina; Wojcik, Andrzej; Creanga, Dorina

    2015-03-01

    An experimental study was accomplished to compare estimation methods of ionizing radiations genotoxicity in mammalian cell cultures by means of two cytogenetic parameters with focus on aberrant cells characterized by multiple chromosomal damages. In vitro study was carried out on the genotoxicity of low-medium doses of 190 kV X-rays absorbed in Chinese hamster ovary cell cultures. Micronuclei and ten types of chromosomal aberrations were identified with Giemsa dying and optical microscope screening. The first parameter consisting in micronuclei relative frequency has led to higher linear correlation coefficient than the second one consistent with chromosomal aberrations relative frequency. However, the latter parameter estimated as the sum of all chromosomal aberrations appeared to be more sensitive to radiation dose increasing in the studied dose range, from 0 to 3 Gy. The number of micronuclei occurring simultaneously in a single cell was not higher than 3, while the number of chromosomal aberrations observed in the same cell reached the value of 5 for doses over 1 Gy. Polynomial dose-response curves were evidenced for cells with Ni micronuclei (i=1,3) while non-monotonic curves were evidenced through detailed analysis of aberrant cells with Ni chromosomal changes [Formula: see text] - in concordance with in vitro studies from literature. The investigation could be important for public health issues where micronucleus screening is routinely applied but also for research purposes where various chromosomal aberrations could be of particular interest.

  2. Micronuclei versus Chromosomal Aberrations Induced by X-Ray in Radiosensitive Mammalian Cells

    PubMed Central

    PLAMADEALA, Cristina; WOJCIK, Andrzej; CREANGA, Dorina

    2015-01-01

    Background: An experimental study was accomplished to compare estimation methods of ionizing radiations genotoxicity in mammalian cell cultures by means of two cytogenetic parameters with focus on aberrant cells characterized by multiple chromosomal damages. Methods: In vitro study was carried out on the genotoxicity of low-medium doses of 190 kV X-rays absorbed in Chinese hamster ovary cell cultures. Micronuclei and ten types of chromosomal aberrations were identified with Giemsa dying and optical microscope screening. Results: The first parameter consisting in micronuclei relative frequency has led to higher linear correlation coefficient than the second one consistent with chromosomal aberrations relative frequency. However, the latter parameter estimated as the sum of all chromosomal aberrations appeared to be more sensitive to radiation dose increasing in the studied dose range, from 0 to 3 Gy. The number of micronuclei occurring simultaneously in a single cell was not higher than 3, while the number of chromosomal aberrations observed in the same cell reached the value of 5 for doses over 1 Gy. Conclusion: Polynomial dose-response curves were evidenced for cells with Ni micronuclei (i=1,3) while non-monotonic curves were evidenced through detailed analysis of aberrant cells with Ni chromosomal changes (i=(1,5)¯) - in concordance with in vitro studies from literature. The investigation could be important for public health issues where micronucleus screening is routinely applied but also for research purposes where various chromosomal aberrations could be of particular interest. PMID:25905075

  3. Nerve growth factor loaded heparin/chitosan scaffolds for accelerating peripheral nerve regeneration.

    PubMed

    Li, Guicai; Xiao, Qinzhi; Zhang, Luzhong; Zhao, Yahong; Yang, Yumin

    2017-09-01

    Artificial chitosan scaffolds have been widely investigated for peripheral nerve regeneration. However, the effect was not as good as that of autologous grafts and therefore could not meet the clinical requirement. In the present study, the nerve growth factor (NGF) loaded heparin/chitosan scaffolds were fabricated via electrostatic interaction for further improving nerve regeneration. The physicochemical properties including morphology, wettability and composition were measured. The heparin immobilization, NGF loading and release were quantitatively and qualitatively characterized, respectively. The effect of NGF loaded heparin/chitosan scaffolds on nerve regeneration was evaluated by Schwann cells culture for different periods. The results showed that the heparin immobilization and NGF loading did not cause the change of bulk properties of chitosan scaffolds except for morphology and wettability. The pre-immobilization of heparin in chitosan scaffolds could enhance the stability of subsequently loaded NGF. The NGF loaded heparin/chitosan scaffolds could obviously improve the attachment and proliferation of Schwann cells in vitro. More importantly, the NGF loaded heparin/chitosan scaffolds could effectively promote the morphology development of Schwann cells. The study may provide a useful experimental basis to design and develop artificial implants for peripheral nerve regeneration and other tissue regeneration. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Mechanical properties of a bioabsorbable nerve guide tube for long nerve defects.

    PubMed

    Ichihara, S; Facca, S; Liverneaux, P; Inada, Y; Takigawa, T; Kaneko, K; Nakamura, T

    2015-09-01

    The mechanical properties of nerve guide tubes must be taken into consideration when they are being developed. We previously reported the feasibility of using 50:50 tubes in a canine 40mm peroneal nerve defect model, where 50:50 represents the proportion of poly(L-lactic) acid (PLLA) and polyglycolic acid (PGA). The aim of the current study was to show that 50:50 tubes have suitable mechanical properties for repairing long nerve defects. Four types of nerve guide tubes made with PLLA to PGA fiber ratios of 100:0 (i.e. 100% PLLA) (100:0 tube), 50:50 (50:50 tube), 10:90 (10:90 tube), and 0:100 (0:100 tube) were designed and created using a tubular braiding machine. Their mechanical properties were examined in vitro (up to 16 weeks). In compression testing, 50:50 tubes had the highest normalized force value, followed in order by the 100:0, 10:90, and 0:100 tubes up to 8 weeks after immersion. From the point of view of biomechanics and bioresorbability, out of the 4 tube types tested, 50:50 tubes appeared to have the optimal mechanical properties for longer nerve defects. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  5. Morphological studies of the vestibular nerve

    NASA Technical Reports Server (NTRS)

    Bergstroem, B.

    1973-01-01

    The anatomy of the intratemporal part of the vestibular nerve in man, and the possible age related degenerative changes in the nerve were studied. The form and structure of the vestibular ganglion was studied with the light microscope. A numerical analysis of the vestibular nerve, and caliber spectra of the myelinated fibers in the vestibular nerve branches were studied in individuals of varying ages. It was found that the peripheral endings of the vestibular nerve form a complicated pattern inside the vestibular sensory epithelia. A detailed description of the sensory cells and their surface organelles is included.

  6. [Morphologic changes during neuroplastic nerve restoration].

    PubMed

    Bakalski, E P; Rozhkov, E N

    1976-06-01

    The dynamics of ultrastructural changes in plastic recovery of the function of the additional nerve by the anterior branch of the second cervical nerve was studied. The nerve cells at the level of the donor-nerve were found to be highly reactive and plastic. It was established that in the process of heterogenic regeneration of the nerve the most substantial changes in neuronal structures were observed during the first two months. The cysterns of the endoplasmic network remained dilated for a long time after platic operation with might be related with the increased protein metabolism in the neuron.

  7. Aberrant phenotypes in peripheral T cell lymphomas.

    PubMed Central

    Hastrup, N; Ralfkiaer, E; Pallesen, G

    1989-01-01

    Seventy six peripheral T cell lymphomas were examined immunohistologically to test their reactivity with a panel of monoclonal antibodies against 11 T cell associated antigens (CD1-8, CD27, UCHL1, and the T cell antigen receptor). Sixty two (82%) lymphomas showed aberrant phenotypes, and four main categories were distinguished as follows: (i) lack of one or several pan-T cell antigens (49, 64% of the cases); (ii) loss of both the CD4 and CD8 antigens (11, 15% of the cases); (iii) coexpression of the CD4 and CD8 antigens (13, 17% of the cases); and (iv) expression of the CD1 antigen (eight, 11% of the cases). No correlation was seen between the occurrence of aberrant phenotypes and the histological subtype. It is concluded that the demonstration of an aberrant phenotype is a valuable supplement to histological assessment in the diagnosis of peripheral T cell lymphomas. It is recommended that the panel of monoclonal antibodies against T cell differentiation antigens should be fairly large, as apparently any antigen may be lost in the process of malignant transformation. Images Figure PMID:2469701

  8. Nerve stepping stone has minimal impact in aiding regeneration across long acellular nerve allografts.

    PubMed

    Yan, Ying; Hunter, Daniel A; Schellhardt, Lauren; Ee, Xueping; Snyder-Warwick, Alison K; Moore, Amy M; Mackinnon, Susan E; Wood, Matthew D

    2018-02-01

    Acellular nerve allografts (ANAs) yield less consistent favorable outcomes compared with autografts for long gap reconstructions. We evaluated whether a hybrid ANA can improve 6-cm gap reconstruction. Rat sciatic nerve was transected and repaired with either 6-cm hybrid or control ANAs. Hybrid ANAs were generated using a 1-cm cellular isograft between 2.5-cm ANAs, whereas control ANAs had no isograft. Outcomes were assessed by graft gene and marker expression (n = 4; at 4 weeks) and motor recovery and nerve histology (n = 10; at 20 weeks). Hybrid ANAs modified graft gene and marker expression and promoted modest axon regeneration across the 6-cm defect compared with control ANA (P < 0.05), but yielded no muscle recovery. Control ANAs had no appreciable axon regeneration across the 6-cm defect. A hybrid ANA confers minimal motor recovery benefits for regeneration across long gaps. Clinically, the authors will continue to reconstruct long nerve gaps with autografts. Muscle Nerve 57: 260-267, 2018. © 2017 Wiley Periodicals, Inc.

  9. The role of aberrant salience and self-concept clarity in psychotic-like experiences.

    PubMed

    Cicero, David C; Becker, Theresa M; Martin, Elizabeth A; Docherty, Anna R; Kerns, John G

    2013-01-01

    Most theories of psychotic-like experiences posit the involvement of cognitive mechanisms. The current research examined the relations between psychotic-like experiences and two cognitive mechanisms, high aberrant salience and low self-concept clarity. In particular, we examined whether aberrant salience, or the incorrect assignment of importance to neutral stimuli, and low self-concept clarity interacted to predict psychotic-like experiences. The current research included three large samples (n = 667, 724, 744) of participants and oversampled for increased schizotypal personality traits. In all three studies, an interaction between aberrant salience and self-concept clarity was found such that participants with high aberrant salience and low self-concept clarity had the highest levels of psychotic-like experiences. In addition, aberrant salience and self-concept clarity interacted to predict a supplemental measure of delusions in Study 2. In Study 3, in contrast to low self-concept clarity, neuroticism did not interact with aberrant salience to predict psychotic-like experiences, suggesting that the relation between low self-concept clarity and psychosis may not be a result of neuroticism. Additionally, aberrant salience and self-concept clarity did not interact to predict two other SPD criteria, social anhedonia or trait paranoia, which suggests the interaction is specific to psychotic-like experiences. Overall, our results are consistent with several cognitive models of psychosis suggesting that aberrant salience and self-concept clarity might be important mechanisms in the occurrence of psychotic-like symptoms.

  10. The Role of Aberrant Salience and Self-Concept Clarity in Psychotic-Like Experiences

    PubMed Central

    Cicero, David C.; Becker, Theresa M.; Martin, Elizabeth A.; Docherty, Anna R.; Kerns, John G.

    2013-01-01

    Most theories of psychotic-like experiences posit the involvement of social-cognitive mechanisms. The current research examined the relations between psychotic-like experiences and two social-cognitive mechanisms, high aberrant salience and low self-concept clarity. In particular, we examined whether aberrant salience, or the incorrect assignment of importance to neutral stimuli, and low self-concept clarity interacted to predict psychotic-like experiences. The current research included three large samples (n = 667, 724, 744) of participants and over-sampled for increased schizotypal personality traits. In all three studies, an interaction between aberrant salience and self-concept clarity was found such that participants with high aberrant salience and low self-concept clarity had the highest levels of psychotic-like experiences. In addition, aberrant salience and self-concept clarity interacted to predict a supplemental measure of delusions in Study 2. In Study 3, in contrast to low self-concept clarity, neuroticism did not interact with aberrant salience to predict psychotic-like experiences, suggesting that the relation between low self-concept clarity and psychosis may not be due to neuroticism. Additionally, aberrant salience and self-concept clarity did not interact to predict to other schizotypal personality disorder criteria, social anhedonia or trait paranoia, which suggests the interaction is specific to psychotic-like experiences. Overall, our results are consistent with several social-cognitive models of psychosis suggesting that aberrant salience and self-concept clarity might be important mechanisms in the occurrence of psychotic-like symptoms. PMID:22452775

  11. Low-order aberration sensitivity of eighth-order coronagraph masks

    NASA Technical Reports Server (NTRS)

    Shaklan, Stuart B.; Green, Joseph J.

    2005-01-01

    In a recent paper, Kuchner, Crepp, and Ge describe new image-plane coronagraph mask designs that reject to eighth order the leakage of starlight caused by image motion at the mask, resulting in a substantial relaxation of image centroiding requirements compared to previous fourth-order and second-order masks. They also suggest that the new masks are effective at rejecting leakage caused by low-order aberrations (e.g., focus, coma, and astigmatism). In this paper, we derive the sensitivity of eighth-order masks to aberrations of any order and provide simulations of coronagraph behavior in the presence of optical aberrations.We find that the masks leak light as the fourth power of focus, astigmatism, coma, and trefoil. This has tremendous performance advantages for the Terrestrial Planet Finder Coronagraph.

  12. Intraoperative monitoring of the recurrent laryngeal nerve by vagal nerve stimulation in thyroid surgery.

    PubMed

    Farizon, Brigitte; Gavid, Marie; Karkas, Alexandre; Dumollard, Jean-Marc; Peoc'h, Michel; Prades, Jean-Michel

    2017-01-01

    The aim of the present study was to evaluate the thyroarytenoid muscle response during bilateral thyroid surgery using vagal nerve stimulation. 195 patients (390 nerves at risk) underwent a total thyroidectomy. The recurrent laryngeal nerve's function was checked by analyzing the amplitude and the latency of the thyroarytenoid muscle's responses after a vagal nerve's stimulation (0.5 and 1 mA) using the NIM3 Medtronic system. All patients were submitted to preoperative and postoperative laryngoscopy. 20 patients get no thyroarytenoid muscle response to the vagal nerve stimulation, and 14 postoperative recurrent laryngeal nerve palsies were confirmed (3.8 %). Two palsies were present after 6 months (0.51 %). All the patients with muscle's response have normal mobility vocal fold. The test sensitivity was 100 % and the test specificity was 98 %. Physiologically, the mean latencies of the muscular potentials for the right RLN were, respectively, 3.89 and 3.83 ms (p > 0.05) for the stimulation at 0.5 and 1 mA. The mean latencies for the left RLN were, respectively, 6.25 and 6.22 ms for the stimulation at 0.5 and 1 mA (p > 0.05). The difference of the latencies between the right and the left nerve was 2.30 ms (1.75-3.25 ms) with a stimulation of 0.5 or 1 mA (p < 0.05). Thyroarytenoid muscle's response via a vagal nerve stimulation showed a functional asymmetry of the laryngeal adduction with a faster right response. Surgically, this method can predict accurately an immediate postoperative vocal folds function in patients undergoing a bilateral thyroid surgery.

  13. [Isolated traumatic injuries of the axillary nerve. Radial nerve transfer in four cases and literatura review].

    PubMed

    Domínguez-Páez, Miguel; Socolovsky, Mariano; Di Masi, Gilda; Arráez-Sánchez, Miguel Ángel

    2012-11-01

    To analyze the results of an initial series of four cases of traumatic injuries of the axillary nerve, treated by a nerve transfer from the triceps long branch of the radial nerve. An extensive analysis of the literature has also been made. Four patients aged between 21 and 42 years old presenting an isolated traumatic palsy of the axillary nerve were operated between January 2007 and June 2010. All cases were treated by nerve transfer six to eight months after the trauma. The results of these cases are analyzed, the same as the axillary nerve injuries series presented in the literature from 1982. One year after the surgery, all patients improved their abduction a mean of 70° (range 30 to 120°), showing a M4 in the British Medical Council Scale. No patient complained of triceps weakness after the procedure. These results are similar to those published employing primary grafting for the axillary nerve. Isolated injuries of the axillary nerve should be treated with surgery when spontaneous recovery is not verified 6 months after the trauma. Primary repair with grafts is the most popular surgical technique, with a rate of success of approximately 90%. The preliminary results of a nerve transfer employing the long triceps branch are similar, and a definite comparison of both techniques with a bigger number of cases should be done in the future. Copyright © 2012 Sociedad Española de Neurocirugía. Published by Elsevier España. All rights reserved.

  14. Peripheral nerve regeneration using a microporous polylactic acid asymmetric conduit in a rabbit long-gap sciatic nerve transection model.

    PubMed

    Hsu, Shan-Hui; Chan, Shan-Ho; Chiang, Chih-Ming; Chen, Clayton Chi-Chang; Jiang, Ching-Fen

    2011-05-01

    The performance of an asymmetric conduit made of microporous polylactic acid (PLA) in promoting the long-term peripheral nerve regeneration across a 20-mm-long sciatic nerve gap was evaluated by a rabbit sciatic nerve transection model. Magnetic resonance imaging (MRI) was employed to monitor the nerve regeneration process. The extents of nerve regeneration and conduit degradation were quantified by image analysis. Functional and histological analyses were followed to assess nerve reinnervation. MR images showed that the transected nerve was connected at about 4 months. The diameter of the regenerated nerve continued to increase while the conduit was gradually degraded. The conduit was completely degraded in 18 months. The degradation kinetics in vivo was estimated based on MR images. The functional recovery after 18 months was ∼82% based on electrophysiology. The extension range of the operated limb was slowly recuperated to ∼81% at 18 months. Histology showed that nerve bundles were self-assembled after 16-18 months, but the morphologies were still different from those of normal sciatic nerve. This was the first work on the long-term evaluation of peripheral nerve regeneration in a rabbit model, and the first to report the use of MRI to obtain the real-time images of regenerated nerve in a biomaterial conduit as well as to define the degradation rate of the conduit in vivo. The platform established in this study serves to evaluate the regeneration of larger-diameter (>3-mm) nerve across a long-gap bridged by a conduit. Copyright © 2011 Elsevier Ltd. All rights reserved.

  15. Radial nerve dysfunction (image)

    MedlinePlus

    The radial nerve travels down the arm and supplies movement to the triceps muscle at the back of the upper arm. ... the wrist and hand. The usual causes of nerve dysfunction are direct trauma, prolonged pressure on the ...

  16. Distal median nerve dysfunction

    MedlinePlus

    ... Distal median nerve dysfunction is a form of peripheral neuropathy that affects the movement of or sensation in ... and the A.D.A.M. Editorial team. Peripheral Nerve Disorders Read more NIH MedlinePlus Magazine Read more Health ...

  17. Ultrasound-Guided Treatment of Peripheral Nerve Pathology.

    PubMed

    Dettori, Nathan; Choudur, Hema; Chhabra, Avneesh

    2018-07-01

    High-resolution ultrasound serves as a fast, accessible, reliable, and radiation-free tool for anatomical and dynamic evaluation of various peripheral nerves. It can be used not only to identify and diagnose peripheral nerve and perineural pathology accurately but also to guide various nerve and perineural interventions. We describe the normal and pathologic appearances of peripheral nerves, the pathologies commonly affecting the individual peripheral nerves, and the current ultrasound-guided peripheral nerve interventions and techniques. Future directions are also highlighted. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  18. Optical aberrations induced by subclinical decentrations of the ablation pattern

    NASA Astrophysics Data System (ADS)

    Mrochen, Michael; Kaemmerer, Maik; Riedel, Peter; Mierdel, Peter; Krinke, Hans-Eberhard; Seiler, Theo

    2000-06-01

    Purpose: The aim of this work was to study the effect of currently used ablation profiles along with eccentric ablations on the increase of higher order aberrations observed after PRK. Material and Methods: The optical aberrations of 10 eyes were tested before and after PRK. Refractive surgery was performed using a ArF-excimer laser system. In all cases, the ablation zone was 6 mm or larger. The spherical equivalent of the correction was ranging from -2.5 D to -6.0 D. The measured wavefront error was compared to numerical simulations done with the reduced eye model and currently used ablation profiles as well as compared with experimental results obtained from ablation on PMMA balls. Results: The aberration measurements result in a considerable change of the spherical- and coma-like wavefront errors. This result was in good correlation with the numerical simulations and the experimental results. Furthermore, it has been derived that the major contribution on the induced higher order aberrations are a result of the small decentration (less than 1.0 mm) of the ablation zone. Conclusions: Higher order spherical- and coma-like aberrations after PRK are mainly determined by the decentration of the ablation zone during laser refractive surgery. However, future laser systems should use efficient eye-tracking systems and aspherical ablation profiles to overcome this problem.

  19. Primary chromatic aberration elimination via optimization work with genetic algorithm

    NASA Astrophysics Data System (ADS)

    Wu, Bo-Wen; Liu, Tung-Kuan; Fang, Yi-Chin; Chou, Jyh-Horng; Tsai, Hsien-Lin; Chang, En-Hao

    2008-09-01

    Chromatic Aberration plays a part in modern optical systems, especially in digitalized and smart optical systems. Much effort has been devoted to eliminating specific chromatic aberration in order to match the demand for advanced digitalized optical products. Basically, the elimination of axial chromatic and lateral color aberration of an optical lens and system depends on the selection of optical glass. According to reports from glass companies all over the world, the number of various newly developed optical glasses in the market exceeds three hundred. However, due to the complexity of a practical optical system, optical designers have so far had difficulty in finding the right solution to eliminate small axial and lateral chromatic aberration except by the Damped Least Squares (DLS) method, which is limited in so far as the DLS method has not yet managed to find a better optical system configuration. In the present research, genetic algorithms are used to replace traditional DLS so as to eliminate axial and lateral chromatic, by combining the theories of geometric optics in Tessar type lenses and a technique involving Binary/Real Encoding, Multiple Dynamic Crossover and Random Gene Mutation to find a much better configuration for optical glasses. By implementing the algorithms outlined in this paper, satisfactory results can be achieved in eliminating axial and lateral color aberration.

  20. DNA Repair Defects and Chromosomal Aberrations

    NASA Technical Reports Server (NTRS)

    Hada, Megumi; George, K. A.; Huff, J. L.; Pluth, J. M.; Cucinotta, F. A.

    2009-01-01

    Yields of chromosome aberrations were assessed in cells deficient in DNA doublestrand break (DSB) repair, after exposure to acute or to low-dose-rate (0.018 Gy/hr) gamma rays or acute high LET iron nuclei. We studied several cell lines including fibroblasts deficient in ATM (ataxia telangiectasia mutated; product of the gene that is mutated in ataxia telangiectasia patients) or NBS (nibrin; product of the gene mutated in the Nijmegen breakage syndrome), and gliomablastoma cells that are proficient or lacking in DNA-dependent protein kinase (DNA-PK) activity. Chromosomes were analyzed using the fluorescence in situ hybridization (FISH) chromosome painting method in cells at the first division post irradiation, and chromosome aberrations were identified as either simple exchanges (translocations and dicentrics) or complex exchanges (involving >2 breaks in 2 or more chromosomes). Gamma irradiation induced greater yields of both simple and complex exchanges in the DSB repair-defective cells than in the normal cells. The quadratic dose-response terms for both simple and complex chromosome exchanges were significantly higher for the ATM- and NBS-deficient lines than for normal fibroblasts. However, in the NBS cells the linear dose-response term was significantly higher only for simple exchanges. The large increases in the quadratic dose-response terms in these repair-defective cell lines points the importance of the functions of ATM and NBS in chromatin modifications to facilitate correct DSB repair and minimize the formation of aberrations. The differences found between ATM- and NBS-deficient cells at low doses suggest that important questions should with regard to applying observations of radiation sensitivity at high dose to low-dose exposures. For aberrations induced by iron nuclei, regression models preferred purely linear dose responses for simple exchanges and quadratic dose responses for complex exchanges. Relative biological effectiveness (RBE) factors of all of

  1. Changes in the blood-nerve barrier after sciatic nerve cold injury: indications supporting early treatment

    PubMed Central

    Li, Hao; Jia, Jian-ping; Xu, Min; Zhang, Lei

    2015-01-01

    Severe edema in the endoneurium can occur after non-freezing cold injury to the peripheral nerve, which suggests damage to the blood-nerve barrier. To determine the effects of cold injury on the blood-nerve barrier, the sciatic nerve on one side of Wistar rats was treated with low temperatures (3–5°C) for 2 hours. The contralateral sciatic nerve was used as a control. We assessed changes in the nerves using Evans blue as a fluid tracer and morphological methods. Excess fluid was found in the endoneurium 1 day after cold injury, though the tight junctions between cells remained closed. From 3 to 5 days after the cold injury, the fluid was still present, but the tight junctions were open. Less tracer leakage was found from 3 to 5 days after the cold injury compared with 1 day after injury. The cold injury resulted in a breakdown of the blood-nerve barrier function, which caused endoneurial edema. However, during the early period, the breakdown of the blood-nerve barrier did not include the opening of tight junctions, but was due to other factors. Excessive fluid volume produced a large increase in the endoneurial fluid pressure, prevented liquid penetration into the endoneurium from the microvasculature. These results suggest that drug treatment to patients with cold injuries should be administered during the early period after injury because it may be more difficult for the drug to reach the injury site through the microcirculation after the tissue fluid pressure becomes elevated. PMID:25878590

  2. High speed wavefront sensorless aberration correction in digital micromirror based confocal microscopy.

    PubMed

    Pozzi, P; Wilding, D; Soloviev, O; Verstraete, H; Bliek, L; Vdovin, G; Verhaegen, M

    2017-01-23

    The quality of fluorescence microscopy images is often impaired by the presence of sample induced optical aberrations. Adaptive optical elements such as deformable mirrors or spatial light modulators can be used to correct aberrations. However, previously reported techniques either require special sample preparation, or time consuming optimization procedures for the correction of static aberrations. This paper reports a technique for optical sectioning fluorescence microscopy capable of correcting dynamic aberrations in any fluorescent sample during the acquisition. This is achieved by implementing adaptive optics in a non conventional confocal microscopy setup, with multiple programmable confocal apertures, in which out of focus light can be separately detected, and used to optimize the correction performance with a sampling frequency an order of magnitude faster than the imaging rate of the system. The paper reports results comparing the correction performances to traditional image optimization algorithms, and demonstrates how the system can compensate for dynamic changes in the aberrations, such as those introduced during a focal stack acquisition though a thick sample.

  3. Comparison of Nerve Excitability Testing, Nerve Conduction Velocity, and Behavioral Observations for Acrylamide Induced Peripheral Neuropathy

    EPA Science Inventory

    Nerve excitability (NE) testing is a sensitive method to test for peripheral neurotoxicity in humans,and may be more sensitive than compound nerve action potential (CNAP) or nerve conduction velocity (NCV).We used acrylamide to compare the NE and CNAP/NCV methods. Behavioral test...

  4. Transient Delayed Facial Nerve Palsy After Inferior Alveolar Nerve Block Anesthesia

    PubMed Central

    Tzermpos, Fotios H.; Cocos, Alina; Kleftogiannis, Matthaios; Zarakas, Marissa; Iatrou, Ioannis

    2012-01-01

    Facial nerve palsy, as a complication of an inferior alveolar nerve block anesthesia, is a rarely reported incident. Based on the time elapsed, from the moment of the injection to the onset of the symptoms, the paralysis could be either immediate or delayed. The purpose of this article is to report a case of delayed facial palsy as a result of inferior alveolar nerve block, which occurred 24 hours after the anesthetic administration and subsided in about 8 weeks. The pathogenesis, treatment, and results of an 8-week follow-up for a 20-year-old patient referred to a private maxillofacial clinic are presented and discussed. The patient's previous medical history was unremarkable. On clinical examination the patient exhibited generalized weakness of the left side of her face with a flat and expressionless appearance, and she was unable to close her left eye. One day before the onset of the symptoms, the patient had visited her dentist for a routine restorative procedure on the lower left first molar and an inferior alveolar block anesthesia was administered. The patient's medical history, clinical appearance, and complete examinations led to the diagnosis of delayed facial nerve palsy. Although neurologic occurrences are rare, dentists should keep in mind that certain dental procedures, such as inferior alveolar block anesthesia, could initiate facial nerve palsy. Attention should be paid during the administration of the anesthetic solution. PMID:22428971

  5. Kinetics of DSB rejoining and formation of simple chromosome exchange aberrations

    NASA Technical Reports Server (NTRS)

    Cucinotta, F. A.; Nikjoo, H.; O'Neill, P.; Goodhead, D. T.

    2000-01-01

    PURPOSE: To investigate the role of kinetics in the processing of DNA double strand breaks (DSB), and the formation of simple chromosome exchange aberrations following X-ray exposures to mammalian cells based on an enzymatic approach. METHODS: Using computer simulations based on a biochemical approach, rate-equations that describe the processing of DSB through the formation of a DNA-enzyme complex were formulated. A second model that allows for competition between two processing pathways was also formulated. The formation of simple exchange aberrations was modelled as misrepair during the recombination of single DSB with undamaged DNA. Non-linear coupled differential equations corresponding to biochemical pathways were solved numerically by fitting to experimental data. RESULTS: When mediated by a DSB repair enzyme complex, the processing of single DSB showed a complex behaviour that gives the appearance of fast and slow components of rejoining. This is due to the time-delay caused by the action time of enzymes in biomolecular reactions. It is shown that the kinetic- and dose-responses of simple chromosome exchange aberrations are well described by a recombination model of DSB interacting with undamaged DNA when aberration formation increases with linear dose-dependence. Competition between two or more recombination processes is shown to lead to the formation of simple exchange aberrations with a dose-dependence similar to that of a linear quadratic model. CONCLUSIONS: Using a minimal number of assumptions, the kinetics and dose response observed experimentally for DSB rejoining and the formation of simple chromosome exchange aberrations are shown to be consistent with kinetic models based on enzymatic reaction approaches. A non-linear dose response for simple exchange aberrations is possible in a model of recombination of DNA containing a DSB with undamaged DNA when two or more pathways compete for DSB repair.

  6. 3D printing strategies for peripheral nerve regeneration.

    PubMed

    Petcu, Eugen B; Midha, Rajiv; McColl, Erin; Popa-Wagner, Aurel; Chirila, Traian V; Dalton, Paul D

    2018-03-23

    After many decades of biomaterials research for peripheral nerve regeneration, a clinical product (the nerve guide), is emerging as a proven alternative for relatively short injury gaps. This review identifies aspects where 3D printing can assist in improving long-distance nerve guide regeneration strategies. These include (1) 3D printing of the customizable nerve guides, (2) fabrication of scaffolds that fill nerve guides, (3) 3D bioprinting of cells within a matrix/bioink into the nerve guide lumen and the (4) establishment of growth factor gradients along the length a nerve guide. The improving resolution of 3D printing technologies will be an important factor for peripheral nerve regeneration, as fascicular-like guiding structures provide one path to improved nerve guidance. The capability of 3D printing to manufacture complex structures from patient data based on existing medical imaging technologies is an exciting aspect that could eventually be applied to treating peripheral nerve injury. Ultimately, the goal of 3D printing in peripheral nerve regeneration is the automated fabrication, potentially customized for the patient, of structures within the nerve guide that significantly outperform the nerve autograft over large gap injuries.

  7. Wavefront aberrations and retinal image quality in different lenticular opacity types and densities.

    PubMed

    Wu, Cheng-Zhe; Jin, Hua; Shen, Zhen-Nv; Li, Ying-Jun; Cui, Xun

    2017-11-10

    To investigate wavefront aberrations in the entire eye and in the internal optics (lens) and retinal image qualities according to different lenticular opacity types and densities. Forty-one eyes with nuclear cataract, 33 eyes with cortical cataract, and 29 eyes with posterior subcapsular cataract were examined. In each group, wavefront aberrations in the entire eye and in the internal optics and retinal image quality were measured using a raytracing aberrometer. Eyes with cortical cataracts showed significantly higher coma-like aberrations compared to the other two groups in both entire eye and internal optic aberrations (P = 0.012 and P = 0.007, respectively). Eyes with nuclear cataract had lower spherical-like aberrations than the other two groups in both entire eye and internal optics aberrations (P < 0.001 and P < 0.001, respectively). In the nuclear cataract group, nuclear lens density was negatively correlated with internal spherical aberrations (r = -0.527, P = 0.005). Wavefront technology is useful for objective and quantitative analysis of retinal image quality deterioration in eyes with different early lenticular opacity types and densities. Understanding the wavefront optical properties of different crystalline lens opacities may help ophthalmic surgeons determine the optimal time to perform cataract surgery.

  8. Surgical Approaches to Facial Nerve Deficits

    PubMed Central

    Birgfeld, Craig; Neligan, Peter

    2011-01-01

    The facial nerve is one of the most commonly injured cranial nerves. Once injured, the effects on form, function, and psyche are profound. We review the anatomy of the facial nerve from the brain stem to its terminal branches. We also discuss the physical exam findings of facial nerve injury at various levels. Finally, we describe various reconstructive options for reanimating the face and restoring both form and function. PMID:22451822

  9. Degeneration and regeneration of motor and sensory nerves: a stereological study of crush lesions in rat facial and mental nerves.

    PubMed

    Barghash, Z; Larsen, J O; Al-Bishri, A; Kahnberg, K-E

    2013-12-01

    The aim of this study was to evaluate the degeneration and regeneration of a sensory nerve and a motor nerve at the histological level after a crush injury. Twenty-five female Wistar rats had their mental nerve and the buccal branch of their facial nerve compressed unilaterally against a glass rod for 30s. Specimens of the compressed nerves and the corresponding control nerves were dissected at 3, 7, and 19 days after surgery. Nerve cross-sections were stained with osmium tetroxide and toluidine blue and analysed using two-dimensional stereology. We found differences between the two nerves both in the normal anatomy and in the regenerative pattern. The mental nerve had a larger cross-sectional area including all tissue components. The mental nerve had a larger volume fraction of myelinated axons and a correspondingly smaller volume fraction of endoneurium. No differences were observed in the degenerative pattern; however, at day 19 the buccal branch had regenerated to the normal number of axons, whereas the mental nerve had only regained 50% of the normal number of axons. We conclude that the regenerative process is faster and/or more complete in the facial nerve (motor function) than it is in the mental nerve (somatosensory function). Copyright © 2013 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  10. Spherical aberration yielding optimum visual performance: Evaluation of intraocular lenses using adaptive optics simulation

    PubMed Central

    Werner, John S.; Elliott, Sarah L.; Choi, Stacey S.; Doble, Nathan

    2009-01-01

    PURPOSE To evaluate the influence of spherical aberration on contrast sensitivity using adaptive optics. SETTING Vision Science and Advanced Retinal Imaging Laboratory, Department of Ophthalmology & Vision Science, University of California, Davis Medical Center, Sacramento, California, USA. METHODS Contrast sensitivity at 8 cycles per degree was evaluated using an adaptive optics system that permitted aberrations to be measured with a Shack-Hartman wavefront sensor and controlled by a 109 actuator continuous-surface deformable mirror that was at a plane conjugate to the observer’s pupil. Vertical Gabor patches were viewed through a 6.3 mm diameter pupil conjugate aperture. Contrast sensitivity was measured with the deformable mirror set to produce 1 of 5 spherical aberration profiles (−0.2 to +0.2 μm). Contrast sensitivity over the range of spherical aberration was fitted with a polynomial function. RESULTS Three observers (age 21 to 24 years) participated. The measured total mean spherical aberration resulting from the spherical aberration profiles produced by the deformable mirror was between −0.15 μm and +0.25 μm. The peak contrast sensitivity of this function for the 3 observers combined occurred at +0.06 μm of spherical aberration. The peak contrast sensitivity was also achieved with positive spherical aberration for observer (mean 0.09). CONCLUSION There was intersubject variability in the measurements; however, the average visual performance was best with the introduction of a small positive spherical aberration. PMID:19545813

  11. Total ocular, anterior corneal and lenticular higher order aberrations in hyperopic, myopic and emmetropic eyes.

    PubMed

    Philip, Krupa; Martinez, Aldo; Ho, Arthur; Conrad, Fabian; Ale, Jit; Mitchell, Paul; Sankaridurg, Padmaja

    2012-01-01

    Total ocular higher order aberrations and corneal topography of myopic, emmetropic and hyperopic eyes of 675 adolescents (16.9 ± 0.7 years) were measured after cycloplegia using COAS aberrometer and Medmont videokeratoscope. Corneal higher order aberrations were computed from the corneal topography maps and lenticular (internal) higher order aberrations derived by subtraction of corneal aberrations from total ocular aberrations. Aberrations were measured for a pupil diameter of 5mm. Multivariate analysis of variance followed by multiple regression analysis found significant difference in the fourth order aberrations (SA RMS, primary spherical aberration coefficient) between the refractive error groups. Hyperopic eyes (+0.083 ± 0.05 μm) had more positive total ocular primary spherical aberration compared to emmetropic (+0.036 ± 0.04 μm) and myopic eyes (low myopia=+0.038 ± 0.05 μm, moderate myopia=+0.026 ± 0.06 μm) (p<0.05). No difference was observed for the anterior corneal spherical aberration. Significantly less negative lenticular spherical aberration was observed for the hyperopic eyes (-0.038 ± 0.05 μm) than myopic (low myopia=-0.088 ± 0.04 μm, moderate myopia=-0.095 ± 0.05 μm) and emmetropic eyes (-0.081 ± 0.04 μm) (p<0.05). These findings suggest the existence of differences in the characteristics of the crystalline lens (asphericity, curvature and gradient refractive index) of hyperopic eyes versus other eyes. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

  12. Correction of cell-induced optical aberrations in a fluorescence fluctuation microscope

    PubMed Central

    Leroux, Charles-Edouard; Grichine, Alexei; Wang, Irène; Delon, Antoine

    2013-01-01

    We describe the effect of optical aberrations on fluorescence fluctuations microscopy (FFM), when focusing through a single living cell. FFM measurements are performed in an aqueous fluorescent solution, and prove to be a highly sensitive tool to assess the optical aberrations introduced by the cell. We demonstrate an adaptive optics (AO) system to remove the aberration-related bias in the FFM measurements. Our data show that AO is not only useful when imaging deep in tissues, but also when performing FFM measurements through a single cellular layer. PMID:23939061

  13. The role of precisely matching fascicles in the quick recovery of nerve function in long peripheral nerve defects

    PubMed Central

    Yan, Liwei; Yao, Zhi; Lin, Tao; Zhu, Qingtang; Qi, Jian; Gu, Liqiang; Fang, Jintao; Zhou, Xiang

    2017-01-01

    Peripheral nerve injury therapy in the clinic remains less than satisfactory. The gold standard of treatment for long peripheral nerve defects is autologous nerve grafts; however, numerous clinical complications are associated with this treatment. As tissue engineering has developed, tissue-engineered nerve grafts (TENGs) have shown potential applications as alternatives to autologous nerve grafts. To verify the important role of the biomimetic pathway of fascicle design in TENGs, we designed an animal model to study the role of the precise matching of fascicles in the effectiveness of nerve function recovery. 24 Sprague-Dawley rats were divided randomly into three groups (eight/group) that corresponded to 100% fascicle matching (100%FM), 50%FM and 0%FM. We selected Sprague–Dawley rat long-gap (15 mm) sciatic nerve defects. In the 6 weeks after surgery, we found that the 100%FM group showed the most effective functional recovery among the three groups. The 100%FM group showed better functional recovery on the basis of the sciatic functional index than the 50%FM and 0%FM groups. According to histological evaluation, the 100%FM group showed more regenerating nerve fibres. Moreover, in terms of the prevention of muscle atrophy, the 100%FM group showed excellent physiological outcomes. The 100%FM as tissue-engineered scaffolds can enhance nerve regeneration and effective functional recovery after the repair of large nerve defects. The results of this study provide a theoretical basis for future TENG designs including biomimetic fascicle pathways for repairing long nerve defects. PMID:28914740

  14. Recording nerve signals in canine sciatic nerves with a flexible penetrating microelectrode array

    NASA Astrophysics Data System (ADS)

    Byun, Donghak; Cho, Sung-Joon; Lee, Byeong Han; Min, Joongkee; Lee, Jong-Hyun; Kim, Sohee

    2017-08-01

    Objective. Previously, we presented the fabrication and characterization of a flexible penetrating microelectrode array (FPMA) as a neural interface device. In the present study, we aim to prove the feasibility of the developed FPMA as a chronic intrafascicular recording tool for peripheral applications. Approach. For recording from the peripheral nerves of medium-sized animals, the FPMA was integrated with an interconnection cable and other parts that were designed to fit canine sciatic nerves. The uniformity of tip exposure and in vitro electrochemical properties of the electrodes were characterized. The capability of the device to acquire in vivo electrophysiological signals was evaluated by implanting the FPMA assembly in canine sciatic nerves acutely as well as chronically for 4 weeks. We also examined the histology of implanted tissues to evaluate the damage caused by the device. Main results. Throughout recording sessions, we observed successful multi-channel recordings (up to 73% of viable electrode channels) of evoked afferent and spontaneous nerve unit spikes with high signal quality (SNR  >  4.9). Also, minor influences of the device implantation on the morphology of nerve tissues were found. Significance. The presented results demonstrate the viability of the developed FPMA device in the peripheral nerves of medium-sized animals, thereby bringing us a step closer to human applications. Furthermore, the obtained data provide a driving force toward a further study for device improvements to be used as a bidirectional neural interface in humans.

  15. Chromosome aberrations in workers occupationally exposed to tritium.

    PubMed

    Tawn, E Janet; Curwen, Gillian B; Riddell, Anthony E

    2018-06-01

    This paper reports the findings of an historical chromosome analysis for unstable aberrations, undertaken on 34 nuclear workers with monitored exposure to tritium. The mean recorded β-particle dose from tritium was 9.33 mGy (range 0.25-79.71 mGy) and the mean occupational dose from external, mainly γ-ray, irradiation was 1.94 mGy (range 0.00-7.71 mGy). The dicentric frequency of 1.91 ± 0.53 × 10 -3 per cell was significantly raised, in comparison with that of 0.61 ± 0.30 × 10 -3 per cell for a group of 66 comparable worker controls unexposed to occupational radiation. The frequency of total aberrations was also significantly higher in the tritium workers. Comparisons with in vitro studies indicate that at these dose levels an increase in aberration frequency is not expected. However, the available historical tritium dose records were produced for the purposes of radiological protection and based on a methodology that has since been updated, so tritium doses are subject to considerable uncertainty. It is therefore recommended that, if possible, tritium doses are reassessed using information on historical recording practices in combination with current dosimetry methodology, and that further chromosome studies are undertaken using modern FISH techniques to establish stable aberration frequencies, as these will provide information on a cumulative biological effect.

  16. Ultrasound-guided peripheral nerve blockade.

    PubMed

    Chin, Ki Jinn; Chan, Vincent

    2008-10-01

    The use of ultrasound for peripheral nerve blockade is becoming popular. Although the feasibility of ultrasound-guided nerve blockade is now clear, it is uncertain at this time whether it represents the new standard for regional anesthesia in terms of efficacy and safety. The ability to visualize nerve location, needle advancement, needle-nerve interaction, and local anesthetic spread makes ultrasound-guided nerve block an attractive option. Study results indicate that these advantages can improve the ease of block performance, block success rates, and complications. At the same time there is evidence that ultrasound-guided regional anesthesia is a unique skill in its own right, and that proficiency in it requires training and experience. Ultrasound is a valuable tool that is now available to the regional anesthesiologist, and it is fast becoming a standard part of practice. It promises to be of especial value to the less experienced practitioner. Ultrasound does not in itself, however, guarantee the efficacy and safety of peripheral nerve blockade. Proper training in its use is required and we can expect to see the development of formal standards and guidelines in this regard.

  17. Comparison of four different nerve conduction techniques of the superficial fibular sensory nerve.

    PubMed

    Saffarian, Mathew R; Condie, Nathan C; Austin, Erica A; Mccausland, Katie E; Andary, Michael T; Sylvain, James R; Mull, Iian R; Zemper, Eric D; Jannausch, Mary L

    2017-09-01

    There are many different nerve conduction study (NCS) techniques to study the superficial fibular sensory nerve (SFSN). We present reference distal latency values and comparative data regarding 4 different NCS for the SFSN. Four different NCS techniques, Spartan technique, Izzo techniques (medial and intermediate dorsal cutaneous branches), and Daube technique, were performed on (114) healthy volunteers. A total of 108 subjects with 164 legs were included. The mean latency of the Spartan technique was longest (3.9 ± 0.3 ms) while the Daube technique was the shortest (3.6 ± 0.7 ms). The mean amplitude of the Daube technique displayed the highest (15.2 ± 8.2 μV) with the Spartan technique having the lowest (8.7 ± 4.2 μV). Among the absent sensory nerve action potentials (SNAPs), the Spartan technique was absent only twice (1.2%) and the Izzo Medial technique was absent more than the other techniques (2.9%). All 4 techniques were reliable methods for obtaining the superficial fibular nerve SNAP, present in 95% of individuals. Muscle Nerve 56: 458-462, 2017. © 2017 Wiley Periodicals, Inc.

  18. Spherical aberration of an optical system and its influence on depth of focus.

    PubMed

    Mikš, Antonín; Pokorný, Petr

    2017-06-10

    This paper analyzes the influence of spherical aberration on the depth of focus of symmetrical optical systems for imaging of axial points. A calculation of a beam's caustics is discussed using ray equations in the image plane and considering longitudinal spherical aberration as well. Concurrently, the influence of aberration coefficients on extremes of such a curve is presented. Afterwards, conditions for aberration coefficients are derived if the Strehl definition should be the same in two symmetrically placed planes with respect to the paraxial image plane. Such conditions for optical systems with large aberrations are derived with the use of geometric-optical approximation where the gyration diameter of the beam in given planes of the optical system is evaluated. Therefore, one can calculate aberration coefficients in such a way that the optical system generates a beam of rays that has the gyration radius in a given interval smaller than the defined limit value. Moreover, one can calculate the maximal depth of focus of the optical system respecting the aforementioned conditions.

  19. Supinator to ulnar nerve transfer via in situ anterior interosseous nerve bridge to restore intrinsic muscle function in combined proximal median and ulnar nerve injury: a novel cadaveric study.

    PubMed

    Namazi, Hamid; HajiVandi, Shahin

    2017-05-01

    In cases of high ulnar nerve palsy, result of nerve repair in term of intrinsic muscle recovery is unsatisfactory. Distal nerve transfer can diminish the regeneration time and improve the results. But, there was no perfect distal nerve transfer for restoring intrinsic hand function in combined proximal median and ulnar nerve injuries. This cadaveric study aims to evaluate the possibility and feasibility of supinator nerve transfer to motor branch of ulnar nerve (MUN). Ten cadaveric upper limbs dissected to identify the location of the supinator branch, anterior interosseous nerve (AIN), and MUN. The AIN was cut from its origin and transferred to the supinator branches. Also, the AIN was distally cut and transferred to the MUN. After nerve coaptation, surface area, fascicle count, and axon number were determined by histologic methods. In all limbs, the proximal and distal stumps of AIN reached the supinator branch and the MUN without tension, respectively. The mean of axon number in the supinator, proximal stump of AIN, distal stump of AIN and MUN branches were 32,426, 45,542, 25,288, and 35,426, respectively. This study showed that transfer of the supinator branches to the MUN is possible via the in situ AIN bridge. The axon count data showed a favorable match between the supinator branches, AIN, and MUN. Therefore, it is suggested that this technique can be useful for patients with combined high median and ulnar nerve injuries. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Lentiviral-mediated transfer of CDNF promotes nerve regeneration and functional recovery after sciatic nerve injury in adult rats

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cheng, Lei; Liu, Yi; Zhao, Hua

    Highlights: •CDNF was successfully transfected by a lentiviral vector into the distal sciatic nerve. •CDNF improved S-100, NF200 expression and nerve regeneration after sciatic injury. •CDNF improved the remyelination and thickness of the regenerated sciatic nerve. •CDNF improved gastrocnemius muscle weight and sciatic functional recovery. -- Abstract: Peripheral nerve injury is often followed by incomplete and unsatisfactory functional recovery and may be associated with sensory and motor impairment of the affected limb. Therefore, a novel method is needed to improve the speed of recovery and the final functional outcome after peripheral nerve injuries. This report investigates the effect of lentiviral-mediatedmore » transfer of conserved dopamine neurotrophic factor (CDNF) on regeneration of the rat peripheral nerve in a transection model in vivo. We observed notable overexpression of CDNF protein in the distal sciatic nerve after recombinant CDNF lentiviral vector application. We evaluated sciatic nerve regeneration after surgery using light and electron microscopy and the functional recovery using the sciatic functional index and target muscle weight. HE staining revealed better ordered structured in the CDNF-treated group at 8 weeks post-surgery. Quantitative analysis of immunohistochemistry of NF200 and S-100 in the CDNF group revealed significant improvement of axonal and Schwann cell regeneration compared with the control groups at 4 weeks and 8 weeks after injury. The thickness of the myelination around the axons in the CDNF group was significantly higher than in the control groups at 8 weeks post-surgery. The CDNF group displayed higher muscle weights and significantly increased sciatic nerve index values. Our findings suggest that CDNF gene therapy could provide durable and stable CDNF protein concentration and has the potential to enhance peripheral nerve regeneration, morphological and functional recovery following nerve injury, which

  1. Ultrasonographic nerve enlargement of the median and ulnar nerves and the cervical nerve roots in patients with demyelinating Charcot-Marie-Tooth disease: distinction from patients with chronic inflammatory demyelinating polyneuropathy.

    PubMed

    Sugimoto, Takamichi; Ochi, Kazuhide; Hosomi, Naohisa; Takahashi, Tetsuya; Ueno, Hiroki; Nakamura, Takeshi; Nagano, Yoshito; Maruyama, Hirofumi; Kohriyama, Tatsuo; Matsumoto, Masayasu

    2013-10-01

    Demyelinating Charcot-Marie-Tooth disease (CMT) and chronic inflammatory demyelinating polyneuropathy (CIDP) are both demyelinating polyneuropathies. The differences in nerve enlargement degree and pattern at multiple evaluation sites/levels are not well known. We investigated the differences in nerve enlargement degree and the distribution pattern of nerve enlargement in patients with demyelinating CMT and CIDP, and verified the appropriate combination of sites/levels to differentiate between these diseases. Ten patients (aged 23-84 years, three females) with demyelinating CMT and 16 patients (aged 30-85 years, five females) with CIDP were evaluated in this study. The nerve sizes were measured at 24 predetermined sites/levels from the median and ulnar nerves and the cervical nerve roots (CNR) using ultrasonography. The evaluation sites/levels were classified into three regions: distal, intermediate and cervical. The number of sites/levels that exhibited nerve enlargement (enlargement site number, ESN) in each region was determined from the 24 sites/levels and from the selected eight screening sites/levels, respectively. The cross-sectional areas of the peripheral nerves were markedly larger at all evaluation sites in patients with demyelinating CMT than in patients with CIDP (p < 0.01). However, the nerve sizes of CNR were not significantly different between patients with either disease. When we evaluated ESN of four selected sites for screening from the intermediate region, the sensitivity and specificity to distinguish between demyelinating CMT and CIDP were 0.90 and 0.94, respectively, with the cut-off value set at four. Nerve ultrasonography is useful to detect nerve enlargement and can clarify morphological differences in nerves between patients with demyelinating CMT and CIDP.

  2. Axillary nerve monitoring during arthroscopic shoulder stabilization.

    PubMed

    Esmail, Adil N; Getz, Charles L; Schwartz, Daniel M; Wierzbowski, Lawrence; Ramsey, Matthew L; Williams, Gerald R

    2005-06-01

    This study evaluated the ability of a novel intraoperative neurophysiologic monitoring method used to locate the axillary nerve, predict relative capsule thickness, and identify impending injury to the axillary nerve during arthroscopic thermal capsulorrhaphy of the shoulder. Prospective cohort study. Twenty consecutive patients with glenohumeral instability were monitored prospectively during arthroscopic shoulder surgery. Axillary nerve mapping and relative capsule thickness estimates were recorded before the stabilization portion of the procedure. During labral repair and/or thermal capsulorrhaphy, continuous and spontaneous electromyography recorded nerve activity. In addition, trans-spinal motor-evoked potentials of the fourth and fifth cervical roots and brachial plexus electrical stimulation, provided real-time information about nerve integrity. Axillary nerve mapping and relative capsule thickness were recorded in all patients. Continuous axillary nerve monitoring was successfully performed in all patients. Eleven of the 20 patients underwent thermal capsulorrhaphy alone or in combination with arthroscopic labral repair. Nine patients underwent arthroscopic labral repair alone. In 4 of the 11 patients who underwent thermal capsulorrhaphy, excessive spontaneous neurotonic electromyographic activity was noted, thereby altering the pattern of heat application by the surgeon. In 1 of these 4 patients, a small increase in the motor latency was noted after the procedure but no clinical deficit was observed. There were no neuromonitoring or clinical neurologic changes observed in the labral repair group without thermal application. At last follow-up, no patient in either group had any clinical evidence of nerve injury or complications from neurophysiologic monitoring. We successfully evaluated the use of intraoperative nerve monitoring to identify axillary nerve position, capsule thickness, and provide real-time identification of impending nerve injury and

  3. Measurement of eye aberrations in a speckle field

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Larichev, A V; Ivanov, P V; Iroshnikov, N G

    2001-12-31

    The influence of speckles on the performance of a Shark-Hartmann wavefront sensor is investigated in the eye aberration studies. The dependence of the phase distortion measurement error on the characteristic speckle size is determined experimentally. Scanning of the reference source was used to suppress the speckle structure of the laser beam scattered by the retina. The technique developed by us made it possible to study the time dependence of the human eye aberrations with a resolution of 30 ms. (laser applications and other topics in quantum electronics)

  4. Phase Aberration and Attenuation Effects on Acoustic Radiation Force-Based Shear Wave Generation.

    PubMed

    Carrascal, Carolina Amador; Aristizabal, Sara; Greenleaf, James F; Urban, Matthew W

    2016-02-01

    Elasticity is measured by shear wave elasticity imaging (SWEI) methods using acoustic radiation force to create the shear waves. Phase aberration and tissue attenuation can hamper the generation of shear waves for in vivo applications. In this study, the effects of phase aberration and attenuation in ultrasound focusing for creating shear waves were explored. This includes the effects of phase shifts and amplitude attenuation on shear wave characteristics such as shear wave amplitude, shear wave speed, shear wave center frequency, and bandwidth. Two samples of swine belly tissue were used to create phase aberration and attenuation experimentally. To explore the phase aberration and attenuation effects individually, tissue experiments were complemented with ultrasound beam simulations using fast object-oriented C++ ultrasound simulator (FOCUS) and shear wave simulations using finite-element-model (FEM) analysis. The ultrasound frequency used to generate shear waves was varied from 3.0 to 4.5 MHz. Results: The measured acoustic pressure and resulting shear wave amplitude decreased approximately 40%-90% with the introduction of the tissue samples. Acoustic intensity and shear wave displacement were correlated for both tissue samples, and the resulting Pearson's correlation coefficients were 0.99 and 0.97. Analysis of shear wave generation with tissue samples (phase aberration and attenuation case), measured phase screen, (only phase aberration case), and FOCUS/FEM model (only attenuation case) showed that tissue attenuation affected the shear wave generation more than tissue aberration. Decreasing the ultrasound frequency helped maintain a focused beam for creation of shear waves in the presence of both phase aberration and attenuation.

  5. Adaptive optics full-field OCT: a resolution almost insensitive to aberrations (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Xiao, Peng; Fink, Mathias; Boccara, A. Claude

    2016-03-01

    A Full-Field OCT (FFOCT) setup coupled to a compact transmissive liquid crystal spatial light modulator (LCSLM) is used to induce or correct aberrations and simulate eye examinations. To reduce the system complexity, strict pupil conjugation was abandoned. During our work on quantifying the effect of geometrical aberrations on FFOCT images, we found that the image resolution is almost insensitive to aberrations. Indeed if the object channel PSF is distorted, its interference with the reference channel conserves the main feature of an unperturbed PSF with only a reduction of the signal level. This unique behavior is specific to the use of a spatially incoherent illumination. Based on this, the FFOCT image intensity was used as the metric for our wavefront sensorless correction. Aberration correction was first conducted on an USAF resolution target with the LSCLM as both aberration generator and corrector. A random aberration mask was induced, and the low-order Zernike Modes were corrected sequentially according to the intensity metric function optimization. A Ficus leaf and a fixed mouse brain tissue slice were also imaged to demonstrate the correction of sample self-induced wavefront distortions. After optimization, more structured information appears for the leaf imaging. And the high-signal fiber-like myelin fiber structures were resolved much more clearly after the whole correction process for mouse brain imaging. Our experiment shows the potential of this compact AO-FFOCT system for aberration correction imaging. This preliminary approach that simulates eyes aberrations correction also opens the path to a simple implementation of FFOCT adaptive optics for retinal examinations.

  6. Unilateral Multiple Facial Nerve Branch Reconstruction Using “End-to-side Loop Graft” Supercharged by Hypoglossal Nerve

    PubMed Central

    Sasaki, Ryo; Takeuchi, Yuichi; Watanabe, Yorikatsu; Niimi, Yosuke; Sakurai, Hiroyuki; Miyata, Mariko; Yamato, Masayuki

    2014-01-01

    Background: Extensive facial nerve defects between the facial nerve trunk and its branches can be clinically reconstructed by incorporating double innervation into an end-to-side loop graft technique. This study developed a new animal model to evaluate the technique’s ability to promote nerve regeneration. Methods: Rats were divided into the intact, nonsupercharge, and supercharge groups. Artificially created facial nerve defects were reconstructed with a nerve graft, which was end-to-end sutured from proximal facial nerve stump to the mandibular branch (nonsupercharge group), or with the graft of which other end was end-to-side sutured to the hypoglossal nerve (supercharge group). And they were evaluated after 30 weeks. Results: Axonal diameter was significantly larger in the supercharge group than in the nonsupercharge group for the buccal (3.78 ± 1.68 vs 3.16 ± 1.22; P < 0.0001) and marginal mandibular branches (3.97 ± 2.31 vs 3.46 ± 1.57; P < 0.0001), but the diameter was significantly larger in the intact group for all branches except the temporal branch. In the supercharge group, compound muscle action potential amplitude was significantly higher than in the nonsupercharge group (4.18 ± 1.49 mV vs 1.87 ± 0.37 mV; P < 0.0001) and similar to that in the intact group (4.11 ± 0.68 mV). Retrograde labeling showed that the mimetic muscles were double-innervated by facial and hypoglossal nerve nuclei in the supercharge group. Conclusions: Multiple facial nerve branch reconstruction with an end-to-side loop graft was able to achieve axonal distribution. Additionally, axonal supercharge from the hypoglossal nerve significantly improved outcomes. PMID:25426357

  7. [Frequency of chromosome aberrations in residents of the Semipalatinsk Oblast].

    PubMed

    Gubitskaia, E G; Akhmatullina, N B; Vsevolodov, E B; Bishnevskaia, S S; Sharipov, I K; Cherednichenko, O G

    1999-06-01

    Cytogenetic analysis of the population of the Beskaragai district of the Semipalatinsk oblast adjacent to the territory of the nuclear test site was conducted by means of an ecological genetic questionnaire and cytogenetic examination of metaphase chromosomes. An increase in the total mutation level in the region was observed. The frequency of chromosome aberrations among the population of the Beskaragai district (3.2%) was statistically significantly (about 1.5 times) higher than the background levels in the clear regions (from 1 to 2%). Furthermore, the frequency of aberrations in adolescents was comparable with that in the adults. The spectrum of chromosome aberrations pointed to a significant contribution of radiation component to the mutagenesis.

  8. The significance of nerve sugar levels for the peripheral nerve impairment of spontaneously diabetic GK (Goto-Kakizaki) rats.

    PubMed

    Suzuki, K; Yen-Chung, H; Toyota, T; Goto, Y; Hirata, Y; Okada, K

    1990-05-01

    This study was carried out to clarify the relationship between the slowing of motor nerve conduction velocity and nerve levels of sorbitol, fructose, glucose and myoinositol in spontaneously diabetic GK (Goto-Kakizaki) rats. The motor nerve conduction velocity in GK rats was constantly lower than in normal controls at three and nine months of age. This constant decrease in motor nerve conduction velocity in GK rats was closely related to glucose intolerance in GK rats soon after birth. Nerve levels of sorbitol, glucose and fructose in GK rats were significantly increased as compared to normal controls at nine months old, but not (except glucose) at three months old. The increase in nerve concentrations of sugars in GK rats was progressive with age. However, levels of glucose, sorbitol and fructose in normal Wistar rats remain unchanged with age. Although nerve myo-inositol levels in GK rats were lower at three and nine months than those of normal controls, a significant difference in myo-inositol levels was observed only at nine months. On the contrary, nerve myo-inositol level in normal Wistar rats did not show age-related change. These findings suggested that both enhanced polyol pathway activity and myo-inositol depletion play important roles in the reduction of motor nerve conduction velocity.

  9. Chronic Nicotine Mitigates Aberrant Inhibitory Motor Learning Induced by Motor Experience under Dopamine Deficiency

    PubMed Central

    Krok, Anne C.; Xu, Jian; Contractor, Anis; McGehee, Daniel S.; Zhuang, Xiaoxi

    2016-01-01

    Although dopamine receptor antagonism has long been associated with impairments in motor performance, more recent studies have shown that dopamine D2 receptor (D2R) antagonism, paired with a motor task, not only impairs motor performance concomitant with the pharmacodynamics of the drug, but also impairs future motor performance once antagonism has been relieved. We have termed this phenomenon “aberrant motor learning” and have suggested that it may contribute to motor symptoms in movement disorders such as Parkinson's disease (PD). Here, we show that chronic nicotine (cNIC), but not acute nicotine, treatment mitigates the acquisition of D2R-antagonist-induced aberrant motor learning in mice. Although cNIC mitigates D2R-mediated aberrant motor learning, cNIC has no effect on D1R-mediated motor learning. β2-containing nicotinic receptors in dopamine neurons likely mediate the protective effect of cNIC against aberrant motor learning, because selective deletion of β2 nicotinic subunits in dopamine neurons reduced D2R-mediated aberrant motor learning. Finally, both cNIC treatment and β2 subunit deletion blunted postsynaptic responses to D2R antagonism. These results suggest that a chronic decrease in function or a downregulation of β2-containing nicotinic receptors protects the striatal network against aberrant plasticity and aberrant motor learning induced by motor experience under dopamine deficiency. SIGNIFICANCE STATEMENT Increasingly, aberrant plasticity and aberrant learning are recognized as contributing to the development and progression of movement disorders. Here, we show that chronic nicotine (cNIC) treatment or specific deletion of β2 nicotinic receptor subunits in dopamine neurons mitigates aberrant motor learning induced by dopamine D2 receptor (D2R) blockade in mice. Moreover, both manipulations also reduced striatal dopamine release and blunt postsynaptic responses to D2R antagonists. These results suggest that chronic downregulation of

  10. Optogenetic probing of nerve and muscle function after facial nerve lesion in the mouse whisker system

    NASA Astrophysics Data System (ADS)

    Bandi, Akhil; Vajtay, Thomas J.; Upadhyay, Aman; Yiantsos, S. Olga; Lee, Christian R.; Margolis, David J.

    2018-02-01

    Optogenetic modulation of neural circuits has opened new avenues into neuroscience research, allowing the control of cellular activity of genetically specified cell types. Optogenetics is still underdeveloped in the peripheral nervous system, yet there are many applications related to sensorimotor function, pain and nerve injury that would be of great benefit. We recently established a method for non-invasive, transdermal optogenetic stimulation of the facial muscles that control whisker movements in mice (Park et al., 2016, eLife, e14140)1. Here we present results comparing the effects of optogenetic stimulation of whisker movements in mice that express channelrhodopsin-2 (ChR2) selectively in either the facial motor nerve (ChAT-ChR2 mice) or muscle (Emx1-ChR2 or ACTA1-ChR2 mice). We tracked changes in nerve and muscle function before and up to 14 days after nerve transection. Optogenetic 460 nm transdermal stimulation of the distal cut nerve showed that nerve degeneration progresses rapidly over 24 hours. In contrast, the whisker movements evoked by optogenetic muscle stimulation were up-regulated after denervation, including increased maximum protraction amplitude, increased sensitivity to low-intensity stimuli, and more sustained muscle contractions (reduced adaptation). Our results indicate that peripheral optogenetic stimulation is a promising technique for probing the timecourse of functional changes of both nerve and muscle, and holds potential for restoring movement after paralysis induced by nerve damage or motoneuron degeneration.

  11. Curcumin promotes nerve regeneration and functional recovery after sciatic nerve crush injury in diabetic rats.

    PubMed

    Ma, Junxiong; Yu, Hailong; Liu, Jun; Chen, Yu; Wang, Qi; Xiang, Liangbi

    2016-01-01

    Curcumin is capable of promoting peripheral nerve regeneration in normal condition. However, it is unclear whether its beneficial effect on nerve regeneration still exists under diabetic mellitus. The present study was designed to investigate such a possibility. Diabetes in rats was developed by a single dose of streptozotocin at 50 mg/kg. Immediately after nerve crush injury, the diabetic rats were intraperitoneally administrated daily for 4 weeks with curcumin (50 mg/kg, 100 mg/kg and 300 mg/kg), or normal saline, respectively. The axonal regeneration was investigated by morphometric analysis and retrograde labeling. The functional recovery was evaluated by electrophysiological studies and behavioral analysis. Axonal regeneration and functional recovery was significantly enhanced by curcumin, which were significantly better than those in vehicle saline group. In addition, high doses of curcumin (100 mg/kg and 300 mg/kg) achieved better axonal regeneration and functional recovery than low dose (50 mg/kg). In conclusion, curcumin is capable of promoting nerve regeneration after sciatic nerve crush injury in diabetes mellitus, highlighting its therapeutic values as a neuroprotective agent for peripheral nerve injury repair in diabetes mellitus. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  12. Pharyngeal arch deficiencies affect taste bud development in the circumvallate papilla with aberrant glossopharyngeal nerve formation.

    PubMed

    Okubo, Tadashi; Takada, Shinji

    2015-07-01

    The pharyngeal arches (PAs) generate cranial organs including the tongue. The taste placodes, formed in particular locations on the embryonic tongue surface, differentiate into taste buds harbored in distinct gustatory papillae. The developing tongue also has a complex supply of cranial nerves through each PA. However, the relationship between the PAs and taste bud development is not fully understood. Ripply3 homozygous mutant mice, which have impaired third/fourth PAs, display a hypoplastic circumvallate papilla and lack taste buds, although the taste placode is normally formed. Formation of the glossopharyngeal ganglia is defective and innervation toward the posterior tongue is completely missing in Ripply3 mutant embryos at E12.5. Moreover, the distribution of neuroblasts derived from the epibranchial placode is severely, but not completely, atenuated, and the neural crest cells are diminished in the third PA region of Ripply3 mutant embryos at E9.5-E10.5. In Tbx1 homozygous mutant embryos, which exhibit another type of deficiency in PA development, the hypoplastic circumvallate papilla is observed along with abnormal formation of the glossopharyngeal ganglia and severely impaired innervation. PA deficiencies affect multiple aspects of taste bud development, including formation of the cranial ganglia and innervation to the posterior tongue. © 2015 Wiley Periodicals, Inc.

  13. Canine urothelial carcinoma: genomically aberrant and comparatively relevant

    PubMed Central

    Shapiro, S. G.; Raghunath, S.; Williams, C.; Motsinger-Reif, A. A.; Cullen, J. M.; Liu, T.; Albertson, D.; Ruvolo, M.; Lucas, A. Bergstrom; Jin, J.; Knapp, D. W.; Schiffman, J. D.

    2015-01-01

    Urothelial carcinoma (UC), also referred to as transitional cell carcinoma (TCC), is the most common bladder malignancy in both human and canine populations. In human UC, numerous studies have demonstrated the prevalence of chromosomal imbalances. Although the histopathology of the disease is similar in both species, studies evaluating the genomic profile of canine UC are lacking, limiting the discovery of key comparative molecular markers associated with driving UC pathogenesis. In the present study, we evaluated 31 primary canine UC biopsies by oligonucleotide array comparative genomic hybridization (oaCGH). Results highlighted the presence of three highly recurrent numerical aberrations: gain of dog chromosome (CFA) 13 and 36 and loss of CFA 19. Regional gains of CFA 13 and 36 were present in 97% and 84% of cases, respectively, and losses on CFA 19 were present in 77% of cases. Fluorescence in situ hybridization (FISH), using targeted bacterial artificial chromosome (BAC) clones and custom Agilent SureFISH probes, was performed to detect and quantify these regions in paraffin-embedded biopsy sections and urine-derived urothelial cells. The data indicate that these three aberrations are potentially diagnostic of UC. Comparison of our canine oaCGH data with that of 285 human cases identified a series of shared copy number aberrations. Using an informatics approach to interrogate the frequency of copy number aberrations across both species, we identified those that had the highest joint probability of association with UC. The most significant joint region contained the gene PABPC1, which should be considered further for its role in UC progression. In addition, cross-species filtering of genome-wide copy number data highlighted several genes as high-profile candidates for further analysis, including CDKN2A, S100A8/9, and LRP1B. We propose that these common aberrations are indicative of an evolutionarily conserved mechanism of pathogenesis and harbor genes key to

  14. Canine urothelial carcinoma: genomically aberrant and comparatively relevant.

    PubMed

    Shapiro, S G; Raghunath, S; Williams, C; Motsinger-Reif, A A; Cullen, J M; Liu, T; Albertson, D; Ruvolo, M; Bergstrom Lucas, A; Jin, J; Knapp, D W; Schiffman, J D; Breen, M

    2015-06-01

    Urothelial carcinoma (UC), also referred to as transitional cell carcinoma (TCC), is the most common bladder malignancy in both human and canine populations. In human UC, numerous studies have demonstrated the prevalence of chromosomal imbalances. Although the histopathology of the disease is similar in both species, studies evaluating the genomic profile of canine UC are lacking, limiting the discovery of key comparative molecular markers associated with driving UC pathogenesis. In the present study, we evaluated 31 primary canine UC biopsies by oligonucleotide array comparative genomic hybridization (oaCGH). Results highlighted the presence of three highly recurrent numerical aberrations: gain of dog chromosome (CFA) 13 and 36 and loss of CFA 19. Regional gains of CFA 13 and 36 were present in 97 % and 84 % of cases, respectively, and losses on CFA 19 were present in 77 % of cases. Fluorescence in situ hybridization (FISH), using targeted bacterial artificial chromosome (BAC) clones and custom Agilent SureFISH probes, was performed to detect and quantify these regions in paraffin-embedded biopsy sections and urine-derived urothelial cells. The data indicate that these three aberrations are potentially diagnostic of UC. Comparison of our canine oaCGH data with that of 285 human cases identified a series of shared copy number aberrations. Using an informatics approach to interrogate the frequency of copy number aberrations across both species, we identified those that had the highest joint probability of association with UC. The most significant joint region contained the gene PABPC1, which should be considered further for its role in UC progression. In addition, cross-species filtering of genome-wide copy number data highlighted several genes as high-profile candidates for further analysis, including CDKN2A, S100A8/9, and LRP1B. We propose that these common aberrations are indicative of an evolutionarily conserved mechanism of pathogenesis and harbor genes

  15. Non-Recurrent Laryngeal Nerve.

    PubMed

    Buła, Grzegorz; Mucha, Ryszard; Paliga, Michał; Koziołek, Henryk; Niedzielski, Zbigniew; Gawrychowski, Jacek

    2015-07-01

    The aim of the study was to assess the frequency of non-recurrent laryngeal nerves (Non-RLN). A total of 6110 patients were operated in our hospital between 1 January 2005 and 31 December 2013 for various goiters (5429) and various types of hyperparathyroidism (618). Laryngeal nerve was exposed during operation in 1700 patients from superior aperture of the chest to superior aperture of the larynx. Identification process of RLN was started with dissecting inferior thyroid artery (ITA) and its junction with the nerve. Then main trunk of the nerve was exposed backwards till the region of superior aperture of the chest together with the end portion till the nerve outlet to the larynx. In the group of 1700 patients, RLN was exposed bilaterally in 1400 (82.4%) and unilaterally in 300 (17.6%). In the group of 3100 dissected RLNs the course of RLN was observed on the right side in 1710 patients and on the left in 1390. Irreversible nature RLN was shown in four cases (0.1%) - four women (02%) aged 42-55 (mean 49.3) - three operated for non-toxic nodular goiter and one for primary hyperparathyroidism. Each time the Non-RLN was seen on the right side. The other patients manifested recurrent character RLN. Moreover, interstitial course of RLN was found on the left side in one man. Non recurrent laryngeal nerve is a rare anatomical variation, occurring more frequently on the right side. Surgeon during surgery of the thyroid and parathyroid glands should be aware of its existence to avoid damage.

  16. Nerve Conduction Study on Sural Nerve among Nepalese Tailors Using Mechanical Sewing Machine.

    PubMed

    Yadav, Prakash Kumar; Yadav, Ram Lochan; Sharma, Deepak; Shah, Dev Kumar; Thakur, Dilip; Limbu, Nirmala; Islam, Md Nazrul

    2017-03-01

    The use of new technologies and innovations are out of access for people living in a developing country like Nepal. The mechanical sewing machine is still in existence at a large scale and dominant all over the country. Tailoring is one of the major occupations adopted by skilled people with lower socioeconomic status and education level. Sural nerves of both right and left legs are exposed to strenuous and chronic stress exerted by chronic paddling of mechanical sewing machine with legs. To evaluate the influence of chronic and strenuous paddling on right and left sural nerves. The study recruited 30 healthy male tailors with median age {34(31-37.25)} years (study group), and, 30 healthy male volunteers with age {34(32-36.25)} years (control group). Anthropometric measurements (age, height, weight, BMI and length of both right and left legs) as well as cardio respiratory measurements [Systolic Blood Pressure (SBP), Dystolic Blood Pressure (DBP), Pules Rate (PR) and Respiratory Rate (RR)] were recorded for each subject. Standard nerve conduction techniques using constant measured distances were applied to evaluate sural nerve (sensory) in both legs of each individual. The differences in variables between the study and control groups were tested using Student's t-test for parametric variables and Mann-Whitney U test for nonparametric variables. A p-value of ≤ 0.05 was considered significant. Age, height, weight, body mass index and leg length were not significantly different between tailors and control groups. Cardio respiratory measurements (SBP, DBP, PR and RR) were also not significantly altered between both the groups. The sensory nerve conduction velocities (m/s) of the right {44.23(42.72-47.83) vs 50(46- 54)} and left sural nerves {45.97±5.86 vs 50.67±6.59} m/s were found significantly reduced in tailors in comparison to control group. Similarly amplitudes (μv) of right sural (20.75±5.42 vs 24.10±5.45) and left sural nerves {18.2(12.43-21.8) vs 32

  17. Nerve Conduction Study on Sural Nerve among Nepalese Tailors Using Mechanical Sewing Machine

    PubMed Central

    Yadav, Ram Lochan; Sharma, Deepak; Shah, Dev Kumar; Thakur, Dilip; Limbu, Nirmala; Islam, Md. Nazrul

    2017-01-01

    Introduction The use of new technologies and innovations are out of access for people living in a developing country like Nepal. The mechanical sewing machine is still in existence at a large scale and dominant all over the country. Tailoring is one of the major occupations adopted by skilled people with lower socioeconomic status and education level. Sural nerves of both right and left legs are exposed to strenuous and chronic stress exerted by chronic paddling of mechanical sewing machine with legs. Aim To evaluate the influence of chronic and strenuous paddling on right and left sural nerves. Materials and Methods The study recruited 30 healthy male tailors with median age {34(31-37.25)} years (study group), and, 30 healthy male volunteers with age {34(32-36.25)} years (control group). Anthropometric measurements (age, height, weight, BMI and length of both right and left legs) as well as cardio respiratory measurements [Systolic Blood Pressure (SBP), Dystolic Blood Pressure (DBP), Pules Rate (PR) and Respiratory Rate (RR)] were recorded for each subject. Standard nerve conduction techniques using constant measured distances were applied to evaluate sural nerve (sensory) in both legs of each individual. The differences in variables between the study and control groups were tested using Student’s t-test for parametric variables and Mann-Whitney U test for nonparametric variables. A p-value of ≤ 0.05 was considered significant. Results Age, height, weight, body mass index and leg length were not significantly different between tailors and control groups. Cardio respiratory measurements (SBP, DBP, PR and RR) were also not significantly altered between both the groups. The sensory nerve conduction velocities (m/s) of the right {44.23(42.72-47.83) vs 50(46- 54)} and left sural nerves {45.97±5.86 vs 50.67±6.59} m/s were found significantly reduced in tailors in comparison to control group. Similarly amplitudes (μv) of right sural (20.75±5.42 vs 24.10±5

  18. 40 CFR 799.9537 - TSCA in vitro mammalian chromosome aberration test.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... aberration test. 799.9537 Section 799.9537 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... MIXTURE TESTING REQUIREMENTS Health Effects Test Guidelines § 799.9537 TSCA in vitro mammalian chromosome aberration test. (a) Scope—(1) Applicability. This section is intended to meet testing requirements under...

  19. MELANOPHORE BANDS AND AREAS DUE TO NERVE CUTTING, IN RELATION TO THE PROTRACTED ACTIVITY OF NERVES

    PubMed Central

    Parker, G. H.

    1941-01-01

    1. When appropriate chromatic nerves are cut caudal bands, cephalic areas, and the pelvic fins of the catfish Ameiurus darken. In pale fishes all these areas will sooner or later blanch. By recutting their nerves all such blanched areas will darken again. 2. These observations show that the darkening of caudal bands, areas, and fins on cutting their nerves is not due to paralysis (Brücke), to the obstruction of central influences such as inhibition (Zoond and Eyre), nor to vasomotor disturbances (Hogben), but to activities emanating from the cut itself. 3. The chief agents concerned with the color changes in Ameiurus are three: intermedin from the pituitary gland, acetylcholine from the dispersing nerves (cholinergic fibers), and adrenalin from the concentrating nerves (adrenergic fibers). The first two darken the fish; the third blanches it. In darkening the dispersing nerves appear to initiate the process and to be followed and substantially supplemented by intermedin. 4. Caudal bands blanch by lateral invasion, cephalic areas by lateral invasion and internal disintegration, and pelvic fins by a uniform process of general loss of tint equivalent to internal disintegration. 5. Adrenalin may be carried in such an oil as olive oil and may therefore act as a lipohumor; it is soluble in water and hence may act as a hydrohumor. In lateral invasion (caudal bands, cephalic areas) it probably acts as a lipohumor and in internal disintegration (cephalic areas, pelvic fins) it probably plays the part of a hydrohumor. 6. The duration of the activity of dispersing nerves after they had been cut was tested by means of the oscillograph, by anesthetizing blocks, and by cold-blocks. The nerves of Ameiurus proved to be unsatisfactory for oscillograph tests. An anesthetizing block, magnesium sulfate, is only partly satisfactory. A cold-block, 0°C., is successful to a limited degree. 7. By means of a cold-block it can be shown that dispersing autonomic nerve fibers in Ameiurus can

  20. Polymeric scaffolds for three-dimensional culture of nerve cells: a model of peripheral nerve regeneration

    PubMed Central

    Ayala-Caminero, Radamés; Pinzón-Herrera, Luis; Martinez, Carol A. Rivera; Almodovar, Jorge

    2018-01-01

    Understanding peripheral nerve repair requires the evaluation of 3D structures that serve as platforms for 3D cell culture. Multiple platforms for 3D cell culture have been developed, mimicking peripheral nerve growth and function, in order to study tissue repair or diseases. To recreate an appropriate 3D environment for peripheral nerve cells, key factors are to be considered including: selection of cells, polymeric biomaterials to be used, and fabrication techniques to shape and form the 3D scaffolds for cellular culture. This review focuses on polymeric 3D platforms used for the development of 3D peripheral nerve cell cultures. PMID:29515936

  1. Multiplexed aberration measurement for deep tissue imaging in vivo

    PubMed Central

    Wang, Chen; Liu, Rui; Milkie, Daniel E.; Sun, Wenzhi; Tan, Zhongchao; Kerlin, Aaron; Chen, Tsai-Wen; Kim, Douglas S.; Ji, Na

    2014-01-01

    We describe a multiplexed aberration measurement method that modulates the intensity or phase of light rays at multiple pupil segments in parallel to determine their phase gradients. Applicable to fluorescent-protein-labeled structures of arbitrary complexity, it allows us to obtain diffraction-limited resolution in various samples in vivo. For the strongly scattering mouse brain, a single aberration correction improves structural and functional imaging of fine neuronal processes over a large imaging volume. PMID:25128976

  2. Effect of diabetic retinopathy and panretinal photocoagulation on retinal nerve fiber layer and optic nerve appearance.

    PubMed

    Lim, Michele C; Tanimoto, Suzana A; Furlani, Bruno A; Lum, Brent; Pinto, Luciano M; Eliason, David; Prata, Tiago S; Brandt, James D; Morse, Lawrence S; Park, Susanna S; Melo, Luiz A S

    2009-07-01

    To determine if panretinal photocoagulation (PRP) alters retinal nerve fiber layer (RNFL) thickness and optic nerve appearance. Patients with diabetes who did and did not undergo PRP and nondiabetic control subjects were enrolled in a prospective study. Participants underwent optical coherence tomography of the peripapillary retina and optic nerve. Stereoscopic optic nerve photographs were graded in a masked fashion. Ninety-four eyes of 48 healthy individuals, 89 eyes of 55 diabetic patients who did not undergo PRP, and 37 eyes of 24 subjects with diabetes who underwent PRP were included in this study. Eyes that had been treated with PRP had thinner peripapillary RNFL compared with the other groups; this was statistically significantly different in the inferior (P = .004) and nasal (P = .003) regions. Optic nerve cupping did not increase with severity of disease classification, but the proportion of optic nerves graded as suspicious for glaucoma or as having nonglaucomatous optic neuropathy did (P = .008). These grading categories were associated with thinner RNFL measurements. Diabetic eyes that have been treated with PRP have thinner RNFL than nondiabetic eyes. Optic nerves in eyes treated with PRP are more likely to be graded as abnormal, but their appearance is not necessarily glaucomatous and may be related to thinning of the RNFL.

  3. RADIATION-INDUCED CHROMOSOME ABERRATIONS IN MAN

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sasaki, M.; Ottoman, R.E.; Norman, A.

    1963-10-01

    A study was made of the production and elimination of radioinduced chromosomal aberrations in leukocytes from the peripheral blood of persons exposed to chronic or acute doses of high-energy radiation. Included in the group were radiologists and laboratory scientists, for whom there were available complete records of the radiation dose received during their working life, and a number of distinguished radiologists who have practiced more than 25 yrs and who may have received substantial doses One of seven leukocytes from a distinguished radiologist contained a pair of chromosomes that could be classified as pseudo- diploid. In laboratory personnel for whommore » the doses received were significantly within the prescribed limits, the incidence of pseudo-diploid cells, of dicentrics, and of other chroNonemosomal aberrations was significantly higher than in a more or less comparable control group. (tr-auth)« less

  4. Double peak sensory nerve action potentials to single stimuli in nerve conduction studies.

    PubMed

    Leote, Joao; Pereira, Pedro; Valls-Sole, Josep

    2017-05-01

    In humans, sensory nerve action potentials (SNAPs) can show 2 separate deflections, i.e., double peak potentials (DPp), which necessarily means that 1 peak is delayed with respect to the other. DPps may have various origins and be due to either physical or physiological properties. We review the nature of commonly encountered DPps in clinical practice, provide the most likely interpretations for their physiological origin, and assess their reproducibility and clinical utility. We classified the DPps into 3 categories: (1) simultaneous anodal and cathodal stimulation. (2) simultaneous recording from 2 different nerves at the same site, and (3) SNAP desynchronization. Although the recording of DPps is not a standardized neurophysiological method, their study brings interesting cues about the physiology of nerve stimulation and paves the way for clinical application of such an observation. Muscle Nerve 55: 619-625, 2017. © 2016 Wiley Periodicals, Inc.

  5. Schwannomatosis of Cervical Vagus Nerve.

    PubMed

    Abdulla, Faheem Ahmed; Sasi, M P

    2016-01-01

    Cervical vagal schwannoma is a rare entity among lesions presenting as a neck mass. They are usually slow-growing benign lesions closely associated with the vagus nerve. They are usually solitary and asymptomatic. Multiple schwannomas occurring in patients without neurofibromatosis (NF) are rare and have recently been referred to as schwannomatosis. Here, we present a case of a neck mass that had imaging features suggestive of vagal schwannoma and was operated upon. Intraoperatively, it was discovered to be a case of multiple vagal cervical schwannoma, all directly related to the right vagus nerve, and could be resected from the nerve in toto preserving the function of the vagus nerve. Final HPR confirmed our pre-op suspicion of vagal schwannomatosis.

  6. Human aberrant crypt foci with carcinoma in situ from a patient with sporadic colon cancer.

    PubMed

    Konstantakos, A K; Siu, I M; Pretlow, T G; Stellato, T A; Pretlow, T P

    1996-09-01

    Aberrant crypt foci are putative preneoplastic lesions found in the colons of carcinogen-treated rodents and at an increased frequency in humans at increased risk for colon cancer. There is a strong association between aberrant crypt foci and colon cancer, including many shared phenotypic and genetic alterations. The aim of this study is to present further evidence of a relationship between aberrant crypt foci and colon cancer in humans. Multiple aberrant crypt foci from a single patient were identified in unembedded colonic mucosa. Histological sections of the aberrant crypt foci and adjacent mucosa were evaluated for dysplasia, proliferative activity, and pigment-laden macrophages that were characterized with histochemical techniques. The first patient with sporadic colon cancer identified with aberrant crypt foci with carcinoma in situ is described. It is interesting that this 99-year-old patient had multiple carcinomas in situ, pseudomelanosis coli, and two metachronous colon cancers. These data lend support to the hypothesis that aberrant crypt foci are precursors of some colon cancers.

  7. Automatic phase aberration compensation for digital holographic microscopy based on deep learning background detection.

    PubMed

    Nguyen, Thanh; Bui, Vy; Lam, Van; Raub, Christopher B; Chang, Lin-Ching; Nehmetallah, George

    2017-06-26

    We propose a fully automatic technique to obtain aberration free quantitative phase imaging in digital holographic microscopy (DHM) based on deep learning. The traditional DHM solves the phase aberration compensation problem by manually detecting the background for quantitative measurement. This would be a drawback in real time implementation and for dynamic processes such as cell migration phenomena. A recent automatic aberration compensation approach using principle component analysis (PCA) in DHM avoids human intervention regardless of the cells' motion. However, it corrects spherical/elliptical aberration only and disregards the higher order aberrations. Traditional image segmentation techniques can be employed to spatially detect cell locations. Ideally, automatic image segmentation techniques make real time measurement possible. However, existing automatic unsupervised segmentation techniques have poor performance when applied to DHM phase images because of aberrations and speckle noise. In this paper, we propose a novel method that combines a supervised deep learning technique with convolutional neural network (CNN) and Zernike polynomial fitting (ZPF). The deep learning CNN is implemented to perform automatic background region detection that allows for ZPF to compute the self-conjugated phase to compensate for most aberrations.

  8. 40 CFR 799.9537 - TSCA in vitro mammalian chromosome aberration test.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... demonstrates the sensitivity of the test system. Positive control concentrations should be chosen so that the.... et al. Report from Working Group on In Vitro Tests for Chromosomal Aberrations. Mutation Research 312... aberration test. 799.9537 Section 799.9537 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...

  9. Reconstructive correction of aberrations in nuclear particle spectrographs

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Berz, M.; Joh, K.; Nolen, J.A.

    A method is presented that allows the reconstruction of trajectories in particle spectrographs and the reconstructive correction of residual aberrations that otherwise limit the resolution. Using a computed or fitted high order transfer map that describes the uncorrected aberrations of the spectrograph, it is possible to calculate a map via an analytic recursion relation that allows the computation of the corrected data of interest such as reaction energy and scattering angle as well as the reconstructed trajectories in terms of position measurements in two planes near the focal plane. The technique is only limited by the accuracy of the positionmore » measurements, the incoherent spot sizes, and the accuracy of the transfer map. In practice the method can be expressed as an inversion of a nonlinear map and implemented in the differential algebraic framework. The method is applied to correct residual aberrations in the S800 spectrograph which is under construction at the National Superconducting Cyclotron Laboratory at Michigan State University and to two other high resolution spectrographs.« less

  10. Measuring mental workload: ocular astigmatism aberration as a novel objective index.

    PubMed

    Jiménez, Raimundo; Cárdenas, David; González-Anera, Rosario; Jiménez, José R; Vera, Jesús

    2018-04-01

    This study assessed the effect of two perceptually matched mental tasks with different levels of mental demand on ocular aberrations in a group of young adults. We measured ocular aberration with a wavefront sensor, and total, internal and corneal RMS (root mean square) aberrations were calculated from Zernike coefficients, considering natural and scaled pupils (5, 4.5, and 4 mm). We found that total, internal and corneal astigmatism RMS showed significant differences between mental tasks with natural pupils (p < .05), and this effect was maintained with 5 mm scaled pupils (total RMS astigmatism, p < .05). Consistently, pupil size, intraocular pressure, perceived mental load and cognitive performance were influenced by the level of mental complexity (p < .05 for all). The findings suggest that ocular astigmatism aberration, mediated by intraocular pressure, could be an objective, valid reliable index to evaluate the impact of cognitive processing in conjunction with others physiological markers in real world contexts. Practitioner Summary: The search continues for a valid, reliable, convenient method of measuring mental workload. In this study we found ocular astigmatism aberration is sensitive to the cumulative effect of mental effort. It shows promise of being a novel ocular index which may help to assess mental workload in real situations.

  11. Nerve monitoring-guided selective hypoglossal nerve stimulation in obstructive sleep apnea patients.

    PubMed

    Heiser, Clemens; Hofauer, Benedikt; Lozier, Luke; Woodson, B Tucker; Stark, Thomas

    2016-12-01

    Selective stimulation of the upper airway is a new therapy for obstructive sleep apnea. The aim of the study was to determine if a selective nerve integrity monitoring (NIM) system could aid in precise placement of the cuff electrode in selective upper-airway stimulation. Single-center, prospective clinical trial. Twenty patients who received a selective upper-airway stimulation system (Inspire Medical Systems, Maple Grove, MN) were implanted by using a NIM system. The tongue motions were recorded during surgery and 2 months postoperatively from the transoral view and by transnasal endoscopy. All patients exhibited consistent protrusion at tongue front and tongue base. The nerve monitoring system helped to place the cuff electrode around the protrusion and stiffening branches, while excluding the retractor branches of the hypoglossal nerve. This report demonstrated a novel use of a NIM system to identify the functional separation between inclusion and exclusion branches of the hypoglossal nerve for implantation of a selective upper-airway stimulation system. 4. Laryngoscope, 126:2852-2858, 2016. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

  12. Aberrations for Grazing Incidence Optics

    NASA Technical Reports Server (NTRS)

    Saha, Timo T.

    2008-01-01

    Large number of grazing incidence telescope configurations have been designed and studied. Wolte1 telescopes are commonly used in astronomical applications. Wolter telescopes consist of a paraboloidal primary mirror and a hyperboloidal or an ellipsoidal secondary mirror. There are 8 possible combinations of Wolter telescopes. Out of these possible designs only type 1 and type 2 telescopes are widely used. Type 1 telescope is typically used for x-ray applications and type 2 telescopes are used for EUV applications. Wolter-Schwarzshild (WS) telescopes offer improved image quality over a small field of view. The WS designs are stigmatic and free of third order coma and, therefore, the PSF is significantly better over a small field of view. Typically the image is more symmetric about its centroid. As for the Wolter telescopes there are 8 possible combinations of WS telescopes. These designs have not been widely used because the surface equations are complex parametric equations complicating the analysis and typically the resolution requirements are too low to take full advantage of the WS designs. There are several other design options. Most notable are wide field x-ray telescope designs. Polynomial designs were originally suggested by Burrows4 and hyperboloid-hyperboloid designs for solar physics applications were designed by Harvey5. No general aberration theory exists for grazing incidence telescopes that would cover all the design options. Several authors have studied the aberrations of grazing incidence telescopes. A comprehensive theory of Wolter type 1 and 2 telescopes has been developed. Later this theory was expanded to include all possible combinations of grazing incidence and also normal incidence paraboloid-hyperboloid and paraboloid-ellipsoid telescopes. In this article the aberration theory of Wolter type telescopes is briefly reviewed.

  13. Aberrant Gene Expression in Humans

    PubMed Central

    Yang, Ence; Ji, Guoli; Brinkmeyer-Langford, Candice L.; Cai, James J.

    2015-01-01

    Gene expression as an intermediate molecular phenotype has been a focus of research interest. In particular, studies of expression quantitative trait loci (eQTL) have offered promise for understanding gene regulation through the discovery of genetic variants that explain variation in gene expression levels. Existing eQTL methods are designed for assessing the effects of common variants, but not rare variants. Here, we address the problem by establishing a novel analytical framework for evaluating the effects of rare or private variants on gene expression. Our method starts from the identification of outlier individuals that show markedly different gene expression from the majority of a population, and then reveals the contributions of private SNPs to the aberrant gene expression in these outliers. Using population-scale mRNA sequencing data, we identify outlier individuals using a multivariate approach. We find that outlier individuals are more readily detected with respect to gene sets that include genes involved in cellular regulation and signal transduction, and less likely to be detected with respect to the gene sets with genes involved in metabolic pathways and other fundamental molecular functions. Analysis of polymorphic data suggests that private SNPs of outlier individuals are enriched in the enhancer and promoter regions of corresponding aberrantly-expressed genes, suggesting a specific regulatory role of private SNPs, while the commonly-occurring regulatory genetic variants (i.e., eQTL SNPs) show little evidence of involvement. Additional data suggest that non-genetic factors may also underlie aberrant gene expression. Taken together, our findings advance a novel viewpoint relevant to situations wherein common eQTLs fail to predict gene expression when heritable, rare inter-individual variation exists. The analytical framework we describe, taking into consideration the reality of differential phenotypic robustness, may be valuable for investigating

  14. Intraoperative cochlear nerve mapping with the mobile cochlear nerve compound action potential tracer in vestibular schwannoma surgery.

    PubMed

    Watanabe, Nobuyuki; Ishii, Takuya; Fujitsu, Kazuhiko; Kaku, Shogo; Ichikawa, Teruo; Miyahara, Kosuke; Okada, Tomu; Tanino, Shin; Uriu, Yasuhiro; Murayama, Yuichi

    2018-05-18

    OBJECTIVE The authors describe the usefulness and limitations of the cochlear nerve compound action potential (CNAP) mobile tracer (MCT) that they developed to aid in cochlear nerve mapping during vestibular schwannoma surgery (VSS) for hearing preservation. METHODS This MCT device requires no more than 2 seconds for stable placement on the nerve to obtain the CNAP and thus is able to trace the cochlear nerve instantaneously. Simultaneous bipolar and monopolar recording is possible. The authors present the outcomes of 18 consecutive patients who underwent preoperative useful hearing (defined as class I or II of the Gardner-Robertson classification system) and underwent hearing-preservation VSS with the use of the MCT. Mapping was considered successful when it was possible to detect and trace the cochlear nerve. RESULTS Mapping of the cochlear nerve was successful in 13 of 18 patients (72.2%), and useful hearing was preserved in 11 patients (61.1%). Among 8 patients with large tumors (Koos grade 3 or 4), the rate of successful mapping was 62.5% (5 patients). The rate of hearing preservation in patients with large tumors was 50% (4 patients). CONCLUSIONS In addition to microsurgical presumption of the arrangement of each nerve, frequent probing on and around an unidentified nerve and comparison of each waveform are advisable with the use of both more sensitive monopolar and more location-specific bipolar MCT. MCT proved to be useful in cochlear nerve mapping and may consequently be helpful in hearing preservation. The authors discuss some limitations and problems with this device.

  15. Blunted sympathoinhibitory responses in obesity-related hypertension are due to aberrant central but not peripheral signalling mechanisms

    PubMed Central

    How, Jackie M Y; Wardak, Suhail A; Ameer, Shaik I; Davey, Rachel A; Sartor, Daniela M

    2014-01-01

    The gut hormone cholecystokinin (CCK) acts at subdiaphragmatic vagal afferents to induce renal and splanchnic sympathoinhibition and vasodilatation, via reflex inhibition of a subclass of cardiovascular-controlling neurons in the rostroventrolateral medulla (RVLM). These sympathoinhibitory and vasodilator responses are blunted in obese, hypertensive rats and our aim in the present study was to determine whether this is attributable to (i) altered sensitivity of presympathetic vasomotor RVLM neurons, and (ii) aberrant peripheral or central signalling mechanisms. Using a diet-induced obesity model, male Sprague–Dawley rats exhibited either an obesity-prone (OP) or obesity-resistant (OR) phenotype when placed on a medium high fat diet for 13–15 weeks; control animals were placed on a low fat diet. OP animals had elevated resting arterial pressure compared to OR/control animals (P < 0.05). Barosensitivity of RVLM neurons was significantly attenuated in OP animals (P < 0.05), suggesting altered baroreflex gain. CCK induced inhibitory responses in RVLM neurons of OR/control animals but not OP animals. Subdiaphragmatic vagal nerve responsiveness to CCK and CCK1 receptor mRNA expression in nodose ganglia did not differ between the groups, but CCK induced significantly less Fos-like immunoreactivity in both the nucleus of the solitary tract and the caudal ventrolateral medulla of OP animals compared to controls (P < 0.05). These results suggest that blunted sympathoinhibitory and vasodilator responses in obesity-related hypertension are due to alterations in RVLM neuronal responses, resulting from aberrant central but not peripheral signalling mechanisms. In obesity, blunted sympathoinhibitory mechanisms may lead to increased regional vascular resistance and contribute to the development of hypertension. PMID:24492842

  16. Analysis of Nerve Agent Metabolites from Hair for Long-Term Verification of Nerve Agent Exposure

    DTIC Science & Technology

    2016-05-09

    Analysis of Nerve Agent Metabolites from Hair for Long-Term Verification of Nerve Agent Exposure Amanda S. Appel,† John H. McDonough,‡ Joseph D...feasible. In this study, hair was evaluated as a long-term repository of nerve agent hydrolysis products. Pinacolyl methylphosphonic acid (PMPA...hydrolysis product of soman) and isopropyl methylphosphonic acid (IMPA; hydrolysis product of sarin) were extracted from hair samples with N,N

  17. Ocular wavefront aberrations in the common marmoset Callithrix jacchus: effects of age and refractive error

    PubMed Central

    Coletta, Nancy J.; Marcos, Susana; Troilo, David

    2012-01-01

    The common marmoset, Callithrix jacchus, is a primate model for emmetropization studies. The refractive development of the marmoset eye depends on visual experience, so knowledge of the optical quality of the eye is valuable. We report on the wavefront aberrations of the marmoset eye, measured with a clinical Hartmann-Shack aberrometer (COAS, AMO Wavefront Sciences). Aberrations were measured on both eyes of 23 marmosets whose ages ranged from 18 to 452 days. Twenty-one of the subjects were members of studies of emmetropization and accommodation, and two were untreated normal subjects. Eleven of the 21 experimental subjects had worn monocular diffusers or occluders and ten had worn binocular spectacle lenses of equal power. Monocular deprivation or lens rearing began at about 45 days of age and ended at about 108 days of age. All refractions and aberration measures were performed while the eyes were cyclopleged; most aberration measures were made while subjects were awake, but some control measurements were performed under anesthesia. Wavefront error was expressed as a seventh-order Zernike polynomial expansion, using the Optical Society of America’s naming convention. Aberrations in young marmosets decreased up to about 100 days of age, after which the higher-order RMS aberration leveled off to about 0.10 micron over a 3 mm diameter pupil. Higher-order aberrations were 1.8 times greater when the subjects were under general anesthesia than when they were awake. Young marmoset eyes were characterized by negative spherical aberration. Visually deprived eyes of the monocular deprivation animals had greater wavefront aberrations than their fellow untreated eyes, particularly for asymmetric aberrations in the odd-numbered Zernike orders. Both lens-treated and deprived eyes showed similar significant increases in Z3-3 trefoil aberration, suggesting the increase in trefoil may be related to factors that do not involve visual feedback. PMID:20800078

  18. Persistence of radiation-induced chromosome aberrations in a long-term cell culture.

    PubMed

    Duran, Assumpta; Barquinero, Joan Francesc; Caballín, María Rosa; Ribas, Montserrat; Barrios, Leonardo

    2009-04-01

    The aim of the present study was to evaluate the persistence of chromosome aberrations induced by X rays. FISH painting and mFISH techniques were applied to long-term cultures of irradiated cells. With painting, at 2 Gy the frequency of apparently simple translocations remained almost invariable during all the culture, whereas at 4 Gy a rapid decline was observed between the first and the second samples, followed by a slight decrease until the end of the culture. Apparently simple dicentrics and complex aberrations disappeared after the first sample at 2 and 4 Gy. By mFISH, at 2 Gy the frequency of complete plus one-way translocations remained invariable between the first and last sample, but at 4 Gy a 60% decline was observed. True incomplete simple translocations disappeared at 2 and 4 Gy, indicating that incompleteness could be a factor to consider when the persistence of translocations is analyzed. The analysis by mFISH showed that the frequency of complex aberrations and their complexity increased with dose and tended to disappear in the last sample. Our results indicate that the influence of dose on the decrease in the frequency of simple translocations with time postirradiation cannot be fully explained by the disappearance of true incomplete translocations and complex aberrations. The chromosome involvement was random for radiation-induced exchange aberrations and non-random for total aberrations. Chromosome 7 showed the highest deviations from expected, being less and more involved than expected in the first and last samples, respectively. Some preferential chromosome-chromosome associations were observed, including a coincidence with a cluster from radiogenic chromosome aberrations described in other studies.

  19. Paeoniae alba Radix Promotes Peripheral Nerve Regeneration

    PubMed Central

    Huang, Kun-Shan; Lin, Jaung-Geng; Lee, Han-Chung; Tsai, Fuu-Jen; Bau, Da-Tian; Huang, Chih-Yang; Yao, Chun-Hsu; Chen, Yueh-Sheng

    2011-01-01

    The present study provides in vitro and in vivo evaluation of Paeoniae alba Radix (PR) on peripheral nerve regeneration. In the in vitro study, we found the PR caused a marked enhancement of the nerve growth factor-mediated neurite outgrowth from PC12 cells as well as their expression of growth associated protein 43 and synapsin I. In the in vivo study, silicone rubber chambers filled with the PR water extract were used to bridge a 10-mm sciatic nerve defect in rats. At the conclusion of 8 weeks, regenerated nerves in the PR groups, especially at 1.25 mg ml−1 had a higher rate of successful regeneration across the wide gap, relatively larger mean values of total nerve area, myelinated axon count and blood vessel number, and a significantly larger nerve conductive velocity compared to the control group (P  <  .05). These results suggest that the PR extract can be a potential nerve growth-promoting factor, being salutary in aiding the growth of injured peripheral nerve. PMID:19687191

  20. Accuracy of modal wavefront estimation from eye transverse aberration measurements

    NASA Astrophysics Data System (ADS)

    Chyzh, Igor H.; Sokurenko, Vyacheslav M.

    2001-01-01

    The influence of random errors in measurement of eye transverse aberrations on the accuracy of reconstructing wave aberration as well as ametropia and astigmatism parameters is investigated. The dependence of mentioned errors on a ratio between the number of measurement points and the number of polynomial coefficients is found for different pupil location of measurement points. Recommendations are proposed for setting these ratios.

  1. Recombinant Temporal Aberration Detection Algorithms for Enhanced Biosurveillance

    PubMed Central

    Murphy, Sean Patrick; Burkom, Howard

    2008-01-01

    Objective Broadly, this research aims to improve the outbreak detection performance and, therefore, the cost effectiveness of automated syndromic surveillance systems by building novel, recombinant temporal aberration detection algorithms from components of previously developed detectors. Methods This study decomposes existing temporal aberration detection algorithms into two sequential stages and investigates the individual impact of each stage on outbreak detection performance. The data forecasting stage (Stage 1) generates predictions of time series values a certain number of time steps in the future based on historical data. The anomaly measure stage (Stage 2) compares features of this prediction to corresponding features of the actual time series to compute a statistical anomaly measure. A Monte Carlo simulation procedure is then used to examine the recombinant algorithms’ ability to detect synthetic aberrations injected into authentic syndromic time series. Results New methods obtained with procedural components of published, sometimes widely used, algorithms were compared to the known methods using authentic datasets with plausible stochastic injected signals. Performance improvements were found for some of the recombinant methods, and these improvements were consistent over a range of data types, outbreak types, and outbreak sizes. For gradual outbreaks, the WEWD MovAvg7+WEWD Z-Score recombinant algorithm performed best; for sudden outbreaks, the HW+WEWD Z-Score performed best. Conclusion This decomposition was found not only to yield valuable insight into the effects of the aberration detection algorithms but also to produce novel combinations of data forecasters and anomaly measures with enhanced detection performance. PMID:17947614

  2. Antimutagenic effects of garlic extract on chromosomal aberrations.

    PubMed

    Shukla, Yogeshwer; Taneja, Pankaj

    2002-02-08

    Garlic (Allium sativum) has been used since ancient times, as a spice and also for its medicinal properties. In present set of investigations antimutagenic effect of garlic extract (GE) has been evaluated using 'in vivo chromosomal aberration assay' in Swiss albino mice. Cyclophosphamide (CP), a well-known mutagen, was given at a single dose of 25 mg/kg b.w. intraperitoneally. Pretreatment with 1, 2.5 and 5% of freshly prepared GE was given through oral intubation for 5 days prior to CP administration. Animals from all the groups were sacrificed at sampling times of 24 and 48 h and their bone marrow tissue was analyzed for chromosomal damage. The animals of the positive control group (CP alone) shows a significant increase in chromosomal aberrations both at 24 and 48 h sampling time. GE, alone did not significantly induced aberrations at either sampling time, confirming its non-mutagenicity. However in the GE pre-treated and CP post-treated groups, a dose dependent decrease in cytogenetic damage was recorded. A significant suppression in the chromosomal aberrations was recorded following pretreatment with 2.5 and 5% GE administration. The anticytotoxic effects of GE were also evident, as observed by significant increase in mitotic index, when compared to positive control group. Reduction in CP induced clastogenicity by GE was evident at 24 h and to a much greater extent at 48 h of cell cycle. Thus results of the present investigations revealed that GE has chemopreventive potential against CP induced chromosomal mutations in Swiss albino mice.

  3. Imaging the Facial Nerve: A Contemporary Review

    PubMed Central

    Gupta, Sachin; Mends, Francine; Hagiwara, Mari; Fatterpekar, Girish; Roehm, Pamela C.

    2013-01-01

    Imaging plays a critical role in the evaluation of a number of facial nerve disorders. The facial nerve has a complex anatomical course; thus, a thorough understanding of the course of the facial nerve is essential to localize the sites of pathology. Facial nerve dysfunction can occur from a variety of causes, which can often be identified on imaging. Computed tomography and magnetic resonance imaging are helpful for identifying bony facial canal and soft tissue abnormalities, respectively. Ultrasound of the facial nerve has been used to predict functional outcomes in patients with Bell's palsy. More recently, diffusion tensor tractography has appeared as a new modality which allows three-dimensional display of facial nerve fibers. PMID:23766904

  4. In vivo predegeneration of peripheral nerves: an effective technique to obtain activated Schwann cells for nerve conduits.

    PubMed

    Keilhoff, G; Fansa, H; Schneider, W; Wolf, G

    1999-07-01

    In vivo predegeneration of peripheral nerves is presented as a convenient and effective method to obtain activated Schwann cells and an enhanced cell yield following in vitro cultivation. The experiments conducted in rats were aimed at clinical use in gaining Schwann cell suspensions for filling artificial conduits in order to bridge peripheral nerve gaps. The rat sciatic nerve used as a model was transected distally to the spinal ganglia. Predegeneration in vivo was allowed to take place for 1, 2, 3 and 4 days and up to 1, 2 and 3 weeks. The nerve was then resected and prepared for cell cultivation. Schwann cells cultivated from the contralateral untreated nerve served as control. Immunostaining for S100, nerve growth factor receptor and the adhesion molecules N-cadherin and L1 was used to characterize the general state of the cultures. Viability was assessed by fluorescein fluorescence staining, and the proliferation index was determined by bromodeoxyuridine-DNA incorporation. The Schwann cells from predegenerated nerves revealed an increased proliferation rate compared to the control, whereas fibroblast contamination was decreased. Best results were obtained 1 week after predegeneration.

  5. Measurement technique for in situ characterizing aberrations of projection optics in lithographic tools.

    PubMed

    Wang, Fan; Wang, Xiangzhao; Ma, Mingying

    2006-08-20

    As the feature size decreases, degradation of image quality caused by wavefront aberrations of projection optics in lithographic tools has become a serious problem in the low-k1 process. We propose a novel measurement technique for in situ characterizing aberrations of projection optics in lithographic tools. Considering the impact of the partial coherence illumination, we introduce a novel algorithm that accurately describes the pattern displacement and focus shift induced by aberrations. Employing the algorithm, the measurement condition is extended from three-beam interference to two-, three-, and hybrid-beam interferences. The experiments are performed to measure the aberrations of projection optics in an ArF scanner.

  6. Corneal Curvature, Astigmatism, and Aberrations in Marfan Syndrome with Lens Subluxation: Evaluation by Pentacam HR System.

    PubMed

    Chen, Jiahui; Jing, Qinghe; Tang, Yating; Qian, Dongjin; Lu, Yi; Jiang, Yongxiang

    2018-03-06

    Marfan syndrome (MFS) is associated with abnormalities of corneal biometric characteristics. We conducted a retrospective case-control study including 55 eyes of the MFS patients with lens subluxation and 53 normal eyes of the control subjects to evaluate the corneal curvature, astigmatism and aberrations using a rotating Scheimpflug camera (Pentacam HR). Compared with the control group, the anterior, posterior, and total corneal curvature were flatter in the MFS group. The anterior and total corneal astigmatism were higher in the MFS patients, whereas the posterior corneal astigmatism was not significantly different between the two groups. Regarding the total corneal aberrations, the root mean square (RMS) aberrations, RMS higher-order aberrations and RMS lower-order aberrations increased, whereas the spherical aberration decreased in the MFS patients. Corneal parameters had potential diagnostic values for MFS patients with lens subluxation and the more reasonable cutoffs were the values of corneal curvature <41.35 D, corneal astigmatism >0.85 D and spherical aberration <0.188 μm. Corneal biometric characteristics of MFS patients with lens subluxation include decreased corneal curvature, higher corneal astigmatism, larger corneal aberrations, and lower spherical aberration. Corneal curvature, corneal astigmatism, and spherical aberration are better diagnostic tools for suspicious MFS.

  7. Aberration measurement of projection optics in lithographic tools based on two-beam interference theory.

    PubMed

    Ma, Mingying; Wang, Xiangzhao; Wang, Fan

    2006-11-10

    The degradation of image quality caused by aberrations of projection optics in lithographic tools is a serious problem in optical lithography. We propose what we believe to be a novel technique for measuring aberrations of projection optics based on two-beam interference theory. By utilizing the partial coherent imaging theory, a novel model that accurately characterizes the relative image displacement of a fine grating pattern to a large pattern induced by aberrations is derived. Both even and odd aberrations are extracted independently from the relative image displacements of the printed patterns by two-beam interference imaging of the zeroth and positive first orders. The simulation results show that by using this technique we can measure the aberrations present in the lithographic tool with higher accuracy.

  8. Correcting the wavefront aberration of membrane mirror based on liquid crystal spatial light modulator

    NASA Astrophysics Data System (ADS)

    Yang, Bin; Wei, Yin; Chen, Xinhua; Tang, Minxue

    2014-11-01

    Membrane mirror with flexible polymer film substrate is a new-concept ultra lightweight mirror for space applications. Compared with traditional mirrors, membrane mirror has the advantages of lightweight, folding and deployable, low cost and etc. Due to the surface shape of flexible membrane mirror is easy to deviate from the design surface shape, it will bring wavefront aberration to the optical system. In order to solve this problem, a method of membrane mirror wavefront aberration correction based on the liquid crystal spatial light modulator (LCSLM) will be studied in this paper. The wavefront aberration correction principle of LCSLM is described and the phase modulation property of a LCSLM is measured and analyzed firstly. Then the membrane mirror wavefront aberration correction system is designed and established according to the optical properties of a membrane mirror. The LCSLM and a Hartmann-Shack sensor are used as a wavefront corrector and a wavefront detector, respectively. The detected wavefront aberration is calculated and converted into voltage value on LCSLM for the mirror wavefront aberration correction by programming in Matlab. When in experiment, the wavefront aberration of a glass plane mirror with a diameter of 70 mm is measured and corrected for verifying the feasibility of the experiment system and the correctness of the program. The PV value and RMS value of distorted wavefront are reduced and near diffraction limited optical performance is achieved. On this basis, the wavefront aberration of the aperture center Φ25 mm in a membrane mirror with a diameter of 200 mm is corrected and the errors are analyzed. It provides a means of correcting the wavefront aberration of membrane mirror.

  9. Autologous transplantation with fewer fibers repairs large peripheral nerve defects

    PubMed Central

    Deng, Jiu-xu; Zhang, Dian-yin; Li, Ming; Weng, Jian; Kou, Yu-hui; Zhang, Pei-xun; Han, Na; Chen, Bo; Yin, Xiao-feng; Jiang, Bao-guo

    2017-01-01

    Peripheral nerve injury is a serious disease and its repair is challenging. A cable-style autologous graft is the gold standard for repairing long peripheral nerve defects; however, ensuring that the minimum number of transplanted nerve attains maximum therapeutic effect remains poorly understood. In this study, a rat model of common peroneal nerve defect was established by resecting a 10-mm long right common peroneal nerve. Rats receiving transplantation of the common peroneal nerve in situ were designated as the in situ graft group. Ipsilateral sural nerves (10–30 mm long) were resected to establish the one sural nerve graft group, two sural nerves cable-style nerve graft group and three sural nerves cable-style nerve graft group. Each bundle of the peroneal nerve was 10 mm long. To reduce the barrier effect due to invasion by surrounding tissue and connective-tissue overgrowth between neural stumps, small gap sleeve suture was used in both proximal and distal terminals to allow repair of the injured common peroneal nerve. At three months postoperatively, recovery of nerve function and morphology was observed using osmium tetroxide staining and functional detection. The results showed that the number of regenerated nerve fibers, common peroneal nerve function index, motor nerve conduction velocity, recovery of myodynamia, and wet weight ratios of tibialis anterior muscle were not significantly different among the one sural nerve graft group, two sural nerves cable-style nerve graft group, and three sural nerves cable-style nerve graft group. These data suggest that the repair effect achieved using one sural nerve graft with a lower number of nerve fibers is the same as that achieved using the two sural nerves cable-style nerve graft and three sural nerves cable-style nerve graft. This indicates that according to the ‘multiple amplification’ phenomenon, one small nerve graft can provide a good therapeutic effect for a large peripheral nerve defect. PMID

  10. Enhancing Peripheral Nerve Regeneration with a Novel Drug Delivering Nerve Conduit

    DTIC Science & Technology

    2014-10-01

    tubes of the PLGA nerve conduit. A polyether sulfone (PES) filter membrane, a polydimethyl siloxane (PDMS) plug and silicone sealant (RTV silicone, Dow...harvested from chicken embryos. 1 DRG/well was plated in 24-well plates coated with laminin (1 µg/ml). Finally, different doses of NGF, GDNF and NGF...application in nerve regeneration, Biomedical Microdevices, in preparation, acknowledgement of federal support (yes) Books or other non-periodical, one

  11. Scaffolds for peripheral nerve repair and reconstruction.

    PubMed

    Yi, Sheng; Xu, Lai; Gu, Xiaosong

    2018-06-02

    Trauma-associated peripheral nerve defect is a widespread clinical problem. Autologous nerve grafting, the current gold standard technique for the treatment of peripheral nerve injury, has many internal disadvantages. Emerging studies showed that tissue engineered nerve graft is an effective substitute to autologous nerves. Tissue engineered nerve graft is generally composed of neural scaffolds and incorporating cells and molecules. A variety of biomaterials have been used to construct neural scaffolds, the main component of tissue engineered nerve graft. Synthetic polymers (e.g. silicone, polyglycolic acid, and poly(lactic-co-glycolic acid)) and natural materials (e.g. chitosan, silk fibroin, and extracellular matrix components) are commonly used along or together to build neural scaffolds. Many other materials, including the extracellular matrix, glass fabrics, ceramics, and metallic materials, have also been used to construct neural scaffolds. These biomaterials are fabricated to create specific structures and surface features. Seeding supporting cells and/or incorporating neurotrophic factors to neural scaffolds further improve restoration effects. Preliminary studies demonstrate that clinical applications of these neural scaffolds achieve satisfactory functional recovery. Therefore, tissue engineered nerve graft provides a good alternative to autologous nerve graft and represents a promising frontier in neural tissue engineering. Copyright © 2018 Elsevier Inc. All rights reserved.

  12. Frequency of sister chromatid exchange and chromosomal aberrations in asbestos cement workers.

    PubMed

    Fatma, N; Jain, A K; Rahman, Q

    1991-02-01

    Exposure to asbestos minerals has been associated with a wide variety of adverse health effects including lung cancer, pleural mesothelioma, and cancer of other organs. It was shown previously that asbestos samples collected from a local asbestos factory enhanced sister chromatid exchanges (SCEs) and chromosomal aberrations in vitro using human lymphocytes. In the present study, 22 workers from the same factory and 12 controls were further investigated. Controls were matched for age, sex, and socioeconomic state. The peripheral blood lymphocytes were cultured and harvested at 48 hours for studies of chromosomal aberrations and at 72 hours for SCE frequency determinations. Asbestos workers had a raised mean SCE rate and increased numbers of chromosomal aberrations compared with a control population. Most of the chromosomal aberrations were chromatid gap and break types.

  13. 21 CFR 882.5275 - Nerve cuff.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Nerve cuff. 882.5275 Section 882.5275 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Therapeutic Devices § 882.5275 Nerve cuff. (a) Identification. A nerve cuff...

  14. 21 CFR 882.5275 - Nerve cuff.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Nerve cuff. 882.5275 Section 882.5275 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Therapeutic Devices § 882.5275 Nerve cuff. (a) Identification. A nerve cuff...

  15. Schwannomatosis of Cervical Vagus Nerve

    PubMed Central

    Sasi, M. P.

    2016-01-01

    Cervical vagal schwannoma is a rare entity among lesions presenting as a neck mass. They are usually slow-growing benign lesions closely associated with the vagus nerve. They are usually solitary and asymptomatic. Multiple schwannomas occurring in patients without neurofibromatosis (NF) are rare and have recently been referred to as schwannomatosis. Here, we present a case of a neck mass that had imaging features suggestive of vagal schwannoma and was operated upon. Intraoperatively, it was discovered to be a case of multiple vagal cervical schwannoma, all directly related to the right vagus nerve, and could be resected from the nerve in toto preserving the function of the vagus nerve. Final HPR confirmed our pre-op suspicion of vagal schwannomatosis. PMID:27807496

  16. Higher-order aberrations of lenticular opacities.

    PubMed

    Sachdev, Nisha; Ormonde, Susan E; Sherwin, Trevor; McGhee, Charles N J

    2004-08-01

    To measure and quantify higher-order aberrations induced by different types of lenticular opacities. Department of Ophthalmology, University of Auckland, and Department of Ophthalmology, Auckland Public Hospital, Auckland, New Zealand. Patients with lenticular opacities were recruited from outpatient clinics of a major tertiary referral center for ophthalmology. Patients were included if they had clinically evident, mild to moderate lenticular opacity with no coexisting ocular pathology. Patients were examined using standard preoperative techniques with additional assessment by wavefront aberrometry (Zywave, Bausch & Lomb) and Scheimpflug photography (EAS-1000, Nidek). For comparison, 20 eyes of 10 subjects with no lenticular opacity (control group) were recruited and assessed in an identical manner. Thirty persons were recruited and 40 eyes assessed, 20 with lenticular opacities. Ten eyes had predominantly cortical opacification, and 10 had mainly nuclear opacification. In eyes with predominantly cortical opacification, the mean logMAR uncorrected visual acuity (UCVA) was 0.5 +/- 0.2 (SD) (6/18 Snellen equivalent) and the mean logMAR best spectacle-corrected visual acuity (BSCVA), 0.2 +/- 0.2 (6/9). Analysis of aberrometry data for a 6.0 mm pupil in this group revealed an increase in coma of cosine phase (Z(3), P =.06) and tetrafoil of cosine phase (Z(4), P =.07) compared to eyes in the control group. Eyes with predominantly nuclear opacification had a mean logMAR UCVA of 0.7 +/- 0.2 (6/30) and a logMAR BSCVA of 0.4 +/- 0.2 (6/15). Aberrometry data for this cohort for a 6.0 mm pupil showed a statistically greater amount of spherical aberration (Z(4)(0), P =.001) and tetrafoil of cosine phase (Z(4), P =.005; Z(4)(-4), P =.004). This pilot study suggests that different types of early lenticular opacities induce different wavefront aberration profiles. Predominantly cortical opacification produced an increase in coma and nuclear opacification induced an increase in

  17. Patterns of Aberrant Eating among Pre-Adolescent Children in Foster Care

    ERIC Educational Resources Information Center

    Tarren-Sweeney, Michael

    2006-01-01

    The paper reports epidemiological and phenomenological investigations of aberrant eating among 347 pre-adolescent children in court-ordered foster and kinship care, in New South Wales, Australia. A quarter of children displayed clinically significant aberrant eating problems, with no evidence of gender or age effects. Two distinct patterns were…

  18. Clinical Evaluation of Decellularized Nerve Allograft with Autologous Bone Marrow Stem Cells to Improve Peripheral Nerve Repair and Functional Outcomes

    DTIC Science & Technology

    2017-07-01

    AWARD NUMBER: W81XWH-15-2-0026 TITLE: Clinical Evaluation of Decellularized Nerve Allograft with Autologous Bone Marrow Stem Cells to Improve...of Decellularized Nerve Allograft with 5a. CONTRACT NUMBER Autologous Bone Marrow Stem Cells to Improve Peripheral Nerve 5b. GRANT NUMBER W81XWH...commercially available decellularized processed peripheral nerve allograft scaffold (Avance® Nerve Graft, AxoGen, Alachua FL) with autologous bone marrow

  19. Ultrasonographic demonstration of intraneural neovascularization after penetrating nerve injury.

    PubMed

    Arányi, Zsuzsanna; Csillik, Anita; Dévay, Katalin; Rosero, Maja

    2018-06-01

    Hypervascularization of nerves has been shown to be a pathological sign in some peripheral nerve disorders, but has not been investigated in nerve trauma. An observational cohort study was performed of the intraneural blood flow of 30 patients (34 nerves) with penetrating nerve injuries, before or after nerve reconstruction. All patients underwent electrophysiological assessment, and B-mode and color Doppler ultrasonography. Intraneural hypervascularization proximal to the site of injury was found in all nerves, which was typically marked and had a longitudinal extension of several centimeters. In 6 nerves, some blood flow was also present within the injury site or immediately distal to the injury. No correlation was found between the degree of vascularization and age, size of the scar / neuroma, or degree of reinnervation. Neovascularization of nerves proximal to injury sites appears to be an essential element of nerve regeneration after penetrating nerve injuries. Muscle Nerve 57: 994-999, 2018. © 2018 Wiley Periodicals, Inc.

  20. Modeling cost of ultrasound versus nerve stimulator guidance for nerve blocks with sensitivity analysis.

    PubMed

    Liu, Spencer S; John, Raymond S

    2010-01-01

    Ultrasound guidance for regional anesthesia has increased in popularity. However, the cost of ultrasound versus nerve stimulator guidance is controversial, as multiple and varying cost inputs are involved. Sensitivity analysis allows modeling of different scenarios and determination of the relative importance of each cost input for a given scenario. We modeled cost per patient of ultrasound versus nerve stimulator using single-factor sensitivity analysis for 4 different clinical scenarios designed to span the expected financial impact of ultrasound guidance. The primary cost factors for ultrasound were revenue from billing for ultrasound (85% of variation in final cost), number of patients examined per ultrasound machine (10%), and block success rate (2.6%). In contrast, the most important input factors for nerve stimulator were the success rate of the nerve stimulator block (89%) and the amount of liability payout for failed airway due to rescue general anesthesia (9%). Depending on clinical scenario, ultrasound was either a profit or cost center. If revenue is generated, then ultrasound-guided blocks consistently become a profit center regardless of clinical scenario in our model. Without revenue, the clinical scenario dictates the cost of ultrasound. In an ambulatory setting, ultrasound is highly competitive with nerve stimulator and requires at least a 96% success rate with nerve stimulator before becoming more expensive. In a hospitalized scenario, ultrasound is consistently more expensive as the uniform use of general anesthesia and hospitalization negate any positive cost effects from greater efficiency with ultrasound.