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Sample records for posterior fossa clinicoradiological

  1. Posterior Fossa Tumors.

    PubMed

    Brandão, Lara A; Young Poussaint, Tina

    2017-02-01

    Pediatric brain tumors are the leading cause of death from solid tumors in childhood. The most common posterior fossa tumors in children are medulloblastoma, atypical teratoid/rhabdoid tumor, cerebellar pilocytic astrocytoma, ependymoma, and brainstem glioma. Location, and imaging findings on computed tomography (CT) and conventional MR (cMR) imaging may provide important clues to the most likely diagnosis. Moreover, information obtained from advanced MR imaging techniques increase diagnostic confidence and help distinguish between different histologic tumor types. Here we discuss the most common posterior fossa tumors in children, including typical imaging findings on CT, cMR imaging, and advanced MR imaging studies.

  2. Posterior Fossa Meningioma

    PubMed Central

    Saleh, Essam A.; Taibah, Abdel Kader; Achilli, Vittorio; Aristegui, Miguel; Mazzoni, Antonio; Sanna, Mario

    1994-01-01

    Posterior fossa meningioma is the second most common tumor in the cerebellopontine angle. It has a higher rate of postoperative morbidity and mortality compared to acoustic neuroma. Forty posterior fossa meningioma patients managed in our centers were reviewed. Thirty-nine patients were managed surgically with 42 surgical procedures. The approaches used were the translabyrinthine approach in 18 patients (43%), the modified transcochlear in 11 cases (26%), the petro-occipital transsigmoid in 5 cases (12%), the suboccipital in 4 cases (10%), the petro-occipital trassigmoid transcervical in 2 cases (5%), the petro-occipital transsigmoid transtentorial in 1 case (2%), and a subtemporal transtentorial for another case (2%). Facial nerve anatomical integrity was preserved in 87% of procedures but was interrupted in 5 cases, with 4 of the latter subsequently repaired. Total tumor removal was accomplished in 38 cases. A second-stage total tumor removal is planned for the remaining case. There was only one case of perioperative death and no cases of radiological recurrence so far. ImagesFigure 1Figure 2Figure 3Figure 4p206-bFigure 5p207-bFigure 5 PMID:17171173

  3. Stereolithography for Posterior Fossa Cranioplasty

    PubMed Central

    Agner, Celso; Dujovny, Manuel; Evenhouse, Raymond; Charbel, Fady T.; Sadler, Lewis

    1998-01-01

    Posterior fossa cranioplasty has been suggested for improvement of neurological symptoms following craniectomy. However, there is no particular recommendation in the literature about techniques for prosthesis manufacture and implantation. We report our experience using rapid prototyping technology and stereolithography for pre-surgical implant design and production of cranioplasties. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5 PMID:17171056

  4. Treatment implications of posterior fossa ependymoma subgroups.

    PubMed

    Ramaswamy, Vijay; Taylor, Michael D

    2016-11-15

    Posterior fossa ependymoma comprises two distinct molecular entities, ependymoma_posterior fossa A (EPN_PFA) and ependymoma_posterior fossa B (EPN_PFB), with differentiable gene expression profiles. As yet, the response of the two entities to treatment is unclear. To determine the relationship between the two molecular subgroups of posterior fossa ependymoma and treatment, we studied a cohort of 820 patients with molecularly profiled, clinically annotated posterior fossa ependymomas. We found that the strongest predictor of poor outcome in patients with posterior fossa ependymoma across the entire age spectrum was molecular subgroup EPN_PFA, which was recently reported in the paper entitled "Therapeutic impact of cytoreductive surgery and irradiation of posterior fossa ependymoma in the molecular era: a retrospective multicohort analysis" in the Journal of Clinical Oncology. Patients with incompletely resected EPN_PFA tumors had a very poor outcome despite receiving adjuvant radiation therapy, whereas a substantial proportion of patients with EPN_PFB tumors can be cured with surgery alone.

  5. Congenital basis of posterior fossa anomalies

    PubMed Central

    Cotes, Claudia; Bonfante, Eliana; Lazor, Jillian; Jadhav, Siddharth; Caldas, Maria; Swischuk, Leonard

    2015-01-01

    The classification of posterior fossa congenital anomalies has been a controversial topic. Advances in genetics and imaging have allowed a better understanding of the embryologic development of these abnormalities. A new classification schema correlates the embryologic, morphologic, and genetic bases of these anomalies in order to better distinguish and describe them. Although they provide a better understanding of the clinical aspects and genetics of these disorders, it is crucial for the radiologist to be able to diagnose the congenital posterior fossa anomalies based on their morphology, since neuroimaging is usually the initial step when these disorders are suspected. We divide the most common posterior fossa congenital anomalies into two groups: 1) hindbrain malformations, including diseases with cerebellar or vermian agenesis, aplasia or hypoplasia and cystic posterior fossa anomalies; and 2) cranial vault malformations. In addition, we will review the embryologic development of the posterior fossa and, from the perspective of embryonic development, will describe the imaging appearance of congenital posterior fossa anomalies. Knowledge of the developmental bases of these malformations facilitates detection of the morphological changes identified on imaging, allowing accurate differentiation and diagnosis of congenital posterior fossa anomalies. PMID:26246090

  6. Posterior fossa syndrome—a narrative review

    PubMed Central

    Wahab, Salima S.; Hettige, Samantha; Mankad, Kshtij

    2016-01-01

    Posterior fossa syndrome (PFS), or cerebellar mutism syndrome (CMS), is a collection of neurological symptoms that occur following surgical resection of a posterior fossa tumour, and is characterised by either a reduction or an absence of speech. Some authors suggest that CM is only one symptom of the CMS complex that also includes ataxia, hypotonia and irritability as well as cranial nerve deficits, neurobehavioral changes and urinary retention or incontinence. It is seen almost exclusively in children. In 1985 Rekate et al. published the first work describing CM as a clinical entity, occurring as a consequence of bilateral cerebellar injury. Other associated symptoms include visual impairment, altered mood, impaired swallowing and significant gross and fine motor deficits. The effects of this can have a devastating impact on both the patient and their carers, posing a significant clinical challenge to neurorehabilitation services. The reported incidence was between 8% and 31% of children undergoing surgery for posterior fossa tumour. The underlying pathologies include vasospasm, oedema, and axonal/neuronal injury. Neuroimaging has contributed to a better understanding of the anatomical location of postoperative injury. There have been a number of suggestions for treatment interventions for PFS. However, apart from some individual reports, there have been no clinical trials indicating possible benefit. Occupational therapy, speech and language therapy, as well as neurocognitive support, contribute to the recovery of these patients. PMID:27942479

  7. BAER suppression during posterior fossa dural opening

    PubMed Central

    Shields, Christopher B.; Shields, Lisa B. E.; Jiang, Yi Dan; Yao, Tom; Zhang, Yi Ping; Sun, David A.

    2015-01-01

    Background: Intraoperative monitoring with brainstem auditory evoked responses (BAER) provides an early warning signal of potential neurological injury and may avert tissue damage to the auditory pathway or brainstem. Unexplained loss of the BAER signal in the operating room may present a dilemma to the neurosurgeon. Methods: This paper documents two patients who displayed a unique mechanism of suppression of the BAER apparent within minutes following dural opening for resection of a posterior fossa meningioma. Results: In two patients with anterior cerebellopontine angle and clival meningiomas, there was a significant deterioration of the BAER soon after durotomy but prior to cerebellar retraction and tumor removal. Intracranial structures in the posterior fossa lying between the tumor and dural opening were shifted posteriorly after durotomy. Conclusion: We hypothesized that the cochlear nerve and vessels entering the acoustic meatus were compressed or stretched when subjected to tissue shift. This movement caused cochlear nerve dysfunction that resulted in BAER suppression. BAER was partially restored after the tumor was decompressed, dura repaired, and bone replaced. BAER was not suppressed following durotomy for removal of a meningioma lying posterior to the cochlear complex. Insight into the mechanisms of durotomy-induced BAER inhibition would allay the neurosurgeon's anxiety during the operation. PMID:25883849

  8. Surgical management of posterior fossa metastases.

    PubMed

    Sunderland, Geraint J; Jenkinson, Michael D; Zakaria, Rasheed

    2016-12-01

    The diagnosis of brain metastases is associated with a poor prognosis reflecting uncontrolled primary disease that has spread to the relative sanctuary of the central nervous system. 20 % of brain metastases occur in the posterior fossa and are associated with significant morbidity. The risk of acute hydrocephalus and potential for sudden death means these metastases are often dealt with as emergency cases. This approach means a full pre-operative assessment and staging of underlying disease may be neglected and a proportion of patients undergo comparatively high risk surgery with little or no survival benefit. This study aimed to assess outcomes in patients to identify factors that may assist in case selection. We report a retrospective case series of 92 consecutive patients operated for posterior fossa metastases between 2007 and 2012. Routine demographic data was collected plus data on performance status, primary cancer site, details of surgery, adjuvant treatment and survival. The only independent positive prognostic factors identified on multivariate analysis were good performance status (if Karnofsky performance score >70, hazard ratio (HR) for death 0.36, 95 % confidence interval (CI) 0.18-0.69), adjuvant whole brain radiotherapy (HR 0.37, 95 % CI 0.21-0.65) and adjuvant chemotherapy where there was extracranial disease and non-synchronous presentation (HR 0.51, 95 % CI 0.31-0.82). Patients presenting with posterior fossa metastases may not be investigated as thoroughly as those with supratentorial tumours. Staging and assessment is essential however, and in the meantime emergencies related to tumour mass effect should be managed with steroids and cerebrospinal fluid diversion as required.

  9. Microsurgical anatomy of the posterior fossa cisterns.

    PubMed

    Matsuno, H; Rhoton, A L; Peace, D

    1988-07-01

    The microsurgical anatomy of the posterior fossa cisterns was examined in 15 cadavers using 3X to 40X magnification. Liliequist's membrane was found to split into two arachnoidal sheets as it spreads upward from the dorsum sellae: an upper sheet, called the diencephalic membrane, which attaches to the diencephalon at the posterior edge of the mamillary bodies, and a lower sheet, called the mesencephalic membrane, which attaches along the junction of the midbrain and pons. Several other arachnoidal membranes that separate the cisterns were identified. These include the anterior pontine membrane, which separates the prepontine and cerebellopontine cisterns; the lateral pontomesencephalic membrane, which separates the ambient and cerebellopontine cisterns; the medial pontomedullary membrane, which separates the premedullary and prepontine cisterns; and the lateral pontomedullary membrane, which separates the cerebellopontine and cerebellomedullary cisterns. The three cisterns in which the arachnoid trabeculae and membranes are the most dense and present the greatest obstacle at operation are the interpeduncular and quadrigeminal cisterns and the cisterna magna. Numerous arachnoid membranes were found to intersect the oculomotor nerves. The neural and vascular structures in each cistern are reviewed.

  10. Costello syndrome: Analysis of the posterior cranial fossa in children with posterior fossa crowding.

    PubMed

    Calandrelli, Rosalinda; D'Apolito, Gabriella; Marco, Panfili; Zampino, Giuseppe; Tartaglione, Tommaso; Colosimo, Cesare

    2015-06-01

    This study aimed to assess changes in the posterior cranial fossa (PCF) to shed light on the mechanism of cerebellar herniation in children with Costello syndrome (CS) and posterior fossa crowding. We performed a morphovolumetric PCF analysis on brain magnetic resonance imaging (MRI) in seven children with CS (mean age 31 ± 16 months) comparing the MRI scans with those of seven age-matched healthy subjects.PCF volume (PCFV), PCF brain volume (PCFBV) and cerebellar volume (CeV) were assessed on axial T2-weighted MRI. Morphometric parameters (diameters of the foramen magnum, tentorial angle, basiocciput, supraocciput, basisphenoid and exocciput lengths) were measured on sagittal T1-weighted MRI. The volume of the cerebrospinal fluid (CSF) spaces was calculated as PCFV minus PCFBV.Five out of seven CS children showed tonsillar herniation in the upper cervical canal; no child had hydrocephalus but three out of seven children showed ventriculomegaly. In addition, the PCFV/PCFBV ratio, PCFV, CSF spaces volume, basiocciput, basisphenoid and exocciput lengths and latero-lateral and antero-posterior diameters of the foramen magnum were significantly reduced, whereas no significant changes were found in supraocciput length, PCFBV, CeV or hindbrain volume. The volumetric reduction of the PCF due to bony posterior fossa hypoplasia is a predisposing factor for developing cerebellar tonsillar herniation through the foramen magnum in children with CS. The altered anatomy of the foramen magnum and upward expansion of the PCF secondary to an increased tentorial slope serves to explain the possible mechanism of cerebellar herniation in patients with CS.

  11. Costello syndrome: Analysis of the posterior cranial fossa in children with posterior fossa crowding

    PubMed Central

    D’Apolito, Gabriella; Panfili, Marco; Zampino, Giuseppe; Tartaglione, Tommaso; Colosimo, Cesare

    2015-01-01

    This study aimed to assess changes in the posterior cranial fossa (PCF) to shed light on the mechanism of cerebellar herniation in children with Costello syndrome (CS) and posterior fossa crowding. We performed a morphovolumetric PCF analysis on brain magnetic resonance imaging (MRI) in seven children with CS (mean age 31 ± 16 months) comparing the MRI scans with those of seven age-matched healthy subjects. PCF volume (PCFV), PCF brain volume (PCFBV) and cerebellar volume (CeV) were assessed on axial T2-weighted MRI. Morphometric parameters (diameters of the foramen magnum, tentorial angle, basiocciput, supraocciput, basisphenoid and exocciput lengths) were measured on sagittal T1-weighted MRI. The volume of the cerebrospinal fluid (CSF) spaces was calculated as PCFV minus PCFBV. Five out of seven CS children showed tonsillar herniation in the upper cervical canal; no child had hydrocephalus but three out of seven children showed ventriculomegaly. In addition, the PCFV/PCFBV ratio, PCFV, CSF spaces volume, basiocciput, basisphenoid and exocciput lengths and latero-lateral and antero-posterior diameters of the foramen magnum were significantly reduced, whereas no significant changes were found in supraocciput length, PCFBV, CeV or hindbrain volume The volumetric reduction of the PCF due to bony posterior fossa hypoplasia is a predisposing factor for developing cerebellar tonsillar herniation through the foramen magnum in children with CS. The altered anatomy of the foramen magnum and upward expansion of the PCF secondary to an increased tentorial slope serves to explain the possible mechanism of cerebellar herniation in patients with CS. PMID:26246091

  12. Asystole during posterior fossa surgery: Report of two cases

    PubMed Central

    Goyal, Keshav; Philip, Frenny Ann; Rath, Girija Prasad; Mahajan, Charu; Sujatha, M.; Bharti, Sachidanand Jee; Gupta, Nidhi

    2012-01-01

    Asystole during posterior fossa neurosurgical procedures is not uncommon. Various causes have been implicated, especially when surgical manipulation is carried out in the vicinity of the brain stem. The trigemino-cardiac reflex has been attributed as one of the causes. Here, we report two cases who suffered asystole during the resection of posterior fossa tumors. The vago-glossopharyngeal reflex and the direct stimulation of the brainstem were hypothesized as the causes of asytole. These episodes resolved spontaneously following withdrawal of the surgical stimulus emphasizing the importance of anticipation and vigilance during critical moments of tumor dissection during posterior fossa surgery. PMID:22870159

  13. Rhinocerebral mucormycosis with extension to the posterior fossa: case report.

    PubMed

    Soloniuk, D S; Moreland, D B

    1988-11-01

    A 25-year-old man with juvenile onset diabetes presented with rhinoorbital mucormycosis. He was treated aggressively with orbital extirpation and amphotericin B. Six months later, he presented with posterior fossa extension of the mucormycosis.

  14. Spontaneous defects between the mastoid and posterior cranial fossa.

    PubMed

    Rereddy, Shruthi K; Mattox, Douglas E

    2016-01-01

    Conclusions Spontaneous defects between the mastoid and the posterior cranial fossa are exceedingly rare. Patients with these lesions may have a lower BMI compared to those with middle cranial fossa encephaloceles, but are otherwise demographically similar. This study recommends repair via a transtemporal approach to allow for examination of the entire posterior face of the temporal bone. Objective To describe cases of spontaneous posterior cranial fossa defects. Methods This study reviewed all cases of spontaneous posterior fossa defects presenting to a tertiary referral center over the last decade and described clinical presentation, imaging, operative findings, and outcomes. We also compared these lesions to those previously reported in the literature as well as the more common spontaneous encephaloceles of the middle cranial fossa. Results This study identified five cases with a mean age of 61.4 years, female-to-male ratio of 4:1, and a mean BMI of 31. Three cases presented with spontaneous pneumocephalus, one with CSF otorrhea, and one as an incidental imaging finding. Four defects were found medial to the sigmoid sinus and one was in the lateral retrosigmoid air cells.

  15. Interconnecting the posterior and middle cranial fossae for tumors that traverse Meckel's cave.

    PubMed

    Cheung, S W; Jackler, R K; Pitts, L H; Gutin, P H

    1995-03-01

    Meckel's cave is an avenue for tumor to spread between the posterior and middle cranial fossae. The most common neoplasms that traverse this channel are trigeminal schwannomas and meningiomas. The classic approach to address disease in both cranial fossae involves separate craniotomies. Recent innovations in skull base surgery have made it possible to perform a single opening with simultaneous exposure of the posterior and middle fossae, without undue brain retraction. Tumors with a large middle fossa component and a smaller posterior fossa portion are exposed via subtemporal craniotomy with petrosectomy and tentorium division. However, tumors with a large posterior fossa component and a smaller middle fossa portion in the setting of serviceable hearing are addressed with retrosigmoid craniotomy and petrosectomy. For bilobed tumors with substantial components in both fossae, subtemporal craniotomy combined with varying degrees of transtemporal petrosectomy and tentorium division is employed. The evolution of techniques to address tumors that traverse Meckel's cave is reviewed and a treatment algorithm is proposed.

  16. Management of Cerebrospinal Fluid Leak following Posterior Cranial Fossa Surgery

    PubMed Central

    Altaf, Imran; Vohra, Anjum Habib; Shams, Shahzad

    2016-01-01

    Objective: Cerebrospinal fluid leakage remains a significant cause of morbidity following posterior fossa surgery, and its treatment remains a difficult problem. The aim of the study was to propose a treatment algorithm for its management. Methods: A retrospective, single-center study was conducted on 147 patients who underwent elective posterior fossa surgery for a variety of diseases. Patients with post operative CSF leakage had either been treated initially with conservative measures including re-suturing of the wound, with CSF lumbar drainage to be employed in case the CSF leakage didn’t stop, or the initial intervention was the institution of CSF lumbar drainage simultaneously with conservative measures. VP (ventriculo-peritoneal) shunt was done in patients with gross hydrocephalus on postoperative CT brain. Results: There were 25 (17%) cases of CSF leakage, including 24 incisional CSF leaks and one case of CSF otorrhea. In eight patients with incisional CSF leakage treated initially with conservative measures including re-suturing of the wound, CSF leakage stopped in only two cases. CSF lumbar drainage instituted later on in six cases with persistent leakage stopped the CSF leakage. In fourteen patients managed initially with re-suturing of the wound and concomitant CSF lumbar drainage, CSF leakage settled in all the cases. Two patients with gross hydrocephalus on post operative CT were managed successfully with VP shunt. Re-suturing of the wound with concomitant CSF lumbar drainage was found to be significantly associated (p=0.003) with the stoppage of CSF leakage, and the settlement of meningitis (p= 0.014). Conclusion: Incisional CSF leaks after posterior fossa surgery should be managed with re-suturing of the wound and concomitant CSF lumbar drainage, instead of an initial trial of conservative therapy alone. PMID:28083041

  17. Posterior fossa ruptured dermoid cyst presenting with hydrocephalus

    PubMed Central

    A. Wani, Abrar; Raswan, Uday S.; Malik, Nayil K.; Ramzan, Altaf U.

    2016-01-01

    Dermoid cysts are rare, benign lesions of embryological origin that represent 0.1-0.7% of all intracranial tumors. They are mainly located in the supra tentorial space, especially in the parasellar region. Their location in the posterior fossa remains uncommon. Rupture of intracranial dermoid cysts is a rare phenomenon. We present a case of dermoid cyst, which had ruptured into ventricular system. Computed Tomography and MRI revealed fat in the fourth ventricle, prepontine cistern, and cerebellomedullary cistern. Hydrocephalus was noted. We performed right ventriculo-peritoneal shunt on which patient improved and he continues to remain asymptomatic one year after. PMID:27744466

  18. Magnetic resonance properties of hydrogen: imaging the posterior fossa

    SciTech Connect

    Young, I.R.; Burl, M.; Clarke, G.J.

    1981-11-01

    Posterior fossa scans were performed on five healthy volunteers using a nuclear magnetic resonance (NMR) machine constructed by Thorn-EMI Ltd. Three different NMR scanning sequences were used. In the first, a type of saturation-recovery technique was used to produce images strongly dependent on the density of hydrogen nuclei, but with some dependence on the spin-lattice relaxation time (T/sub 1/). In the second, an inversion-recovery technique was used to produce images with a stronger dependence on the spin-lattice relaxation time. In the third, a spin-echo technique was used to obtain images with a dependence on the spin-spin relaxation time (T/sub 2/). All three types of NMR image were unaffected by bone artifact. Visualization of brain adjacent to the skull base was obtained without loss of detail due to partial-volume effect from bone. The saturation-recovery images highlighted arteries and veins that were clearly visible without the use of contrast agents. The inversion-recovery images showed remarkable gray-white matter differentiation enabling internal structure to be seen within the brainstem and cerebellum. The trigeminal nerve and ganglion were also seen outside the brain. Experience with the spin-echo technique is limited, but the images at the base of the brain show considerable soft-tissue detail. The NMR images of the posterior fossa in this study were comparable in quality to those obtained from a new rotate-rotate x-ray computed tomography machine and were superior in several respects.

  19. Supratentorial Neurometabolic Alterations in Pediatric Survivors of Posterior Fossa Tumors

    SciTech Connect

    Rueckriegel, Stefan M.; Driever, Pablo Hernaiz; Bruhn, Harald

    2012-03-01

    Purpose: Therapy and tumor-related effects such as hypoperfusion, internal hydrocephalus, chemotherapy, and irradiation lead to significant motor and cognitive sequelae in pediatric posterior fossa tumor survivors. A distinct proportion of those factors related to the resulting late effects is hitherto poorly understood. This study aimed at separating the effects of neurotoxic factors on central nervous system metabolism by using H-1 MR spectroscopy to quantify cerebral metabolite concentrations in these patients in comparison to those in age-matched healthy peers. Methods and Materials: Fifteen patients with World Health Organization (WHO) I pilocytic astrocytoma (PA) treated by resection only, 24 patients with WHO IV medulloblastoma (MB), who additionally received chemotherapy and craniospinal irradiation, and 43 healthy peers were investigated using single-volume H-1 MR spectroscopy of parietal white matter and gray matter. Results: Concentrations of N-acetylaspartate (NAA) were significantly decreased in white matter (p < 0.0001) and gray matter (p < 0.0001) of MB patients and in gray matter (p = 0.005) of PA patients, compared to healthy peers. Decreased creatine concentrations in parietal gray matter correlated significantly with older age at diagnosis in both patient groups (MB patients, p = 0.009, r = 0.52; PA patients, p = 0.006, r = 0.7). Longer time periods since diagnosis were associated with lower NAA levels in white matter of PA patients (p = 0.008, r = 0.66). Conclusions: Differently decreased NAA concentrations were observed in both PA and MB groups of posterior fossa tumor patients. We conclude that this reflects a disturbance of the neurometabolic steady state of normal-appearing brain tissue due to the tumor itself and to the impact of surgery in both patient groups. Further incremental decreases of metabolite concentrations in MB patients may point to additional harm caused by irradiation and chemotherapy. The stronger decrease of NAA in MB

  20. [Craniological basis of operative approaches to the structures of posterior cranial fossa using endovideo-monitoring].

    PubMed

    Gaĭvoronskiĭ, A I

    2007-01-01

    Cranioscopic and craniometric characteristics of posterior cranial fossa and correlations between them were studied using 127 skulls with different cranial shape (dolicho-, meso- and brachicraniums). It was found that most of the craniometric characteristics were independent on gender and shape of the skull, while each characteristic had some individual peculiarities. Endovideomonitoring was used to assess the optimality of suboccipital paramedial and retrosigmoid approaches to posterior cranial fossa using 20 heads of the corpses belonging to adult individuals. It was demonstrated that retrosigmoid approach was optimal for the accessibility of major anatomical structures of posterior cranial fossa.

  1. Pressure-supported ventilation for posterior fossa operation.

    PubMed

    Mori, N; Takahashi, H; Yanase, T; Suzuki, M

    1990-03-01

    To maintain enough gas exchange while using spontaneous respiration as a monitor of the normal brainstem function, we tried pressure-supported ventilation (PSV) with a Servo 900C ventilator (Siemens Elema AB, Sweden) on 12 otherwise healthy patients during posterior fossa operation. Ventilation mode was switched from controlled to PSV after the dura was open uneventfully in all cases but one. With a trigger level of -1 to -2 cm H2O, spontaneous respiration was triggered to start the inspiration. With supporting inspiratory pressure of 4-20 cm H2O, PaCO2 was kept at 31.7-45.9 mm Hg. The ventilatory level could be monitored breath by breath by ventilatory frequency, tidal volume, minute volume, and end-tidal CO2 concentration shown on the ventilator system. Apnea was observed in two cases during surgical manipulation around the brainstem. It was indicated immediately by the ventilator's alarm for decreased expiratory minute volume, and no sign of brainstem dysfunction was observed postoperatively. PSV was useful in maintaining adequate ventilation whereas spontaneous respiration was used as an indicator of normal brainstem function. The alarm system of the ventilator was sensitive enough to detect the surgical invasion of the brainstem at a very early stage.

  2. Sandwich Wound Closure Reduces the Risk of Cerebrospinal Fluid Leaks in Posterior Fossa Surgery

    PubMed Central

    Heymanns, Verena; Oseni, Abidemi W.; Alyeldien, Ameer; Maslehaty, Homajoun; Parvin, Richard; Scholz, Martin

    2016-01-01

    Posterior fossa surgery is demanding and hides a significant number of obstacles starting from the approach to the wound closure. The risk of cerebrospinal fluid (CSF) leakage in posterior fossa surgery given in the literature is around 8%. The present study aims to introduce a sandwich closure of the dura in posterior fossa surgery, which reduces significantly the number of CSF leaks (3.8%) in the patients treated in our department. Three hundred and ten patients treated in our hospital in the years 2009-2013 for posterior fossa pathologies were retrospectively evaluated. The dura closure method was as following: lyophilized dura put under the dura and sealed with fibrin glue and sutures, dura adapting stitches, TachoSil® (Takeda Pharma A/S, Roskilde, Denmark), Gelfoam® (Pfizer Inc., New York, NY, USA) and polymethylmethacrylate (osteoclastic craniotomy). The incidence of postsurgical complications associated with the dural closure like CSF leakage, infections, bleeding is evaluated. Only 3.8% of patients developed CSF leakage and only 0.5% needed a second surgery for CSF leakage closure. Two percent had a cerebellar bleeding with no need for re-operation and 3% had a wound infection treated with antibiotics. The sandwich wound closure we are applying for posterior fossa surgery in our patients correlates with a significant reduction of CSF leaks compared to the literature. PMID:27478578

  3. Acute posterior fossa epidural hematoma in a newborn infant with Menkes disease.

    PubMed

    Takeuchi, Satoru; Horikawa, Masahiro; Wakamatsu, Hajime; Hashimoto, Jyunya; Nawashiro, Hiroshi

    2014-02-01

    Epidural hematoma (EDH) in newborn infants is rare compared with other types of intracranial hemorrhages. Furthermore, posterior fossa EDH is extremely rare. We present a case of posterior fossa EDH in an infant with Menkes disease with accessory bones in the occiput. A male infant with a condition diagnosed with Menkes disease by prenatal testing was born at 39 weeks via vacuum extraction. The patient presented with a mild tremor at 2 days after delivery. A brain computed tomography (CT) scan showed an acute EDH in the posterior fossa, extending into the occipitoparietal area. Three-dimensional CT and bone window CT scan revealed several accessory bones, diastasis of 1 accessory suture, a communicated fracture, and a linear fracture in the occipital bone. Furthermore, a bone fragment from a communicated fracture displaced toward the inside. The patient was treated conservatively for EDH because of his good general condition. The hematoma gradually resolved, and his tremor did not recur. We suggest the following mechanism of posterior fossa EDH development in our patient: (1) external force was applied to the occiput inside the birth canal during delivery, resulting in diastasis; (2) a communicated fracture occurred, and a bone fragment displaced toward the inside (linear fracture was caused indirectly by the force); (3) a transverse sinus was injured by the fragment; and (4) EDH developed in both the posterior fossa and supratentorial region. Copper deficiency can also cause fragility of connective tissues, vessels, and bones.

  4. 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

  5. Cranial nerve assessment in posterior fossa tumors with fast imaging employing steady-state acquisition (FIESTA).

    PubMed

    Mikami, Takeshi; Minamida, Yoshihiro; Yamaki, Toshiaki; Koyanagi, Izumi; Nonaka, Tadashi; Houkin, Kiyohiro

    2005-10-01

    Steady-state free precession is widely used for ultra-fast cardiac or abdominal imaging. The purpose of this work was to assess fast imaging employing steady-state acquisition (FIESTA) and to evaluate its efficacy for depiction of the cranial nerve affected by the tumor. Twenty-three consecutive patients with posterior fossa tumors underwent FIESTA sequence after contrast agent administration, and then displacement of the cranial nerve was evaluated. The 23 patients with posterior fossa tumor consisted of 12 schwannomas, eight meningiomas, and three cases of epidermoid. Except in the cases of epidermoid, intensity of all tumors increased on FIESTA imaging of the contrast enhancement. In the schwannoma cases, visualization of the nerve became poorer as the tumor increased in size. In cases of encapsulated meningioma, all the cranial nerves of the posterior fossa were depicted regardless of location. The ability to depict the nerves was also significantly higher in meningioma patients than in schwannoma patients (P<0.05). In cases of epidermoid, extension of the tumors was depicted clearly. Although the FIESTA sequence offers similar contrast to other heavily T2-weighted sequences, it facilitated a superior assessment of the effect of tumors on cranial nerve anatomy. FIESTA sequence was useful for preoperative simulations of posterior fossa tumors.

  6. A Cognitive and Affective Pattern in Posterior Fossa Strokes in Children: A Case Series

    ERIC Educational Resources Information Center

    Kossorotoff, Manoelle; Gonin-Flambois, Coralie; Gitiaux, Cyril; Quijano, Susana; Boddaert, Nathalie; Bahi-Buisson, Nadia; Barnerias, Christine; Dulac, Olivier; Brunelle, Francis; Desguerre, Isabelle

    2010-01-01

    Aim: Posterior fossa strokes account for about 10% of ischaemic strokes in children. Although motor and dysautonomic symptoms are common, to our knowledge cognitive and affective deficits have not been described in the paediatric literature. Our aim, therefore, was to describe these symptoms and deficits. Method: In a retrospective study, we…

  7. Arterial relationships to the nerves and some rigid structures in the posterior cranial fossa.

    PubMed

    Surchev, N

    2008-09-01

    The close relationships between the cranial nerves and the arterial vessels in the posterior cranial fossa are one of the predisposing factors for artery-nerve compression. The aim of this study was to examine the relationships of the vertebral and basilar arteries to some skull and dural structures and the nerves in the posterior cranial fossa. For this purpose, the skull bases and brains of 70 cadavers were studied. The topographic relationships of the vertebral and basilar arteries to the cranial nerves in the posterior cranial fossa were studied and the distances between the arteries and some osseous formations were measured. The most significant variations in arterial position were registered in the lower half of the basilar artery. Direct contact with an artery was established for the hypoglossal canal, jugular tubercle, and jugular foramen. The results reveal additional information about the relationships of the nerves and arteries to the skull and dural formations in the posterior cranial fossa. New quantitative information is given to illustrate them. The conditions for possible artery-nerve compression due to arterial dislocation are discussed and two groups (lines) of compression points are suggested. The medial line comprises of the brain stem points, usually the nerve root entry/exit zone. The lateral line includes the skull eminences, on which the nerves lie, or skull and dural foramina through which they exit the cranial cavity.

  8. Morphometric analysis of posterior fossa in Indian CP angle acoustic schwannoma patients

    PubMed Central

    Patibandla, Mohana Rao; Panigrahi, Manas K.; Gurram, Paniraj L.; Thotakura, Amit Kumar; Kulkarni, Dilip

    2016-01-01

    Aim: To study the morphometry of posterior fossa in Indian CP angle schwannoma patients in order to know its influence on the extent of excision of the CP angle acoustic schwannomas. Materials and Methods: One hundred cases of cerebellopontine angle schwannomas treated surgically by the senior author and 20 controls between January 2006 and June 2011 were consecutively investigated with computed tomography (CT) using the high-resolution CT bone windows before surgery. Evaluation of anatomic parameters of the petrous bone and posterior fossa cavity were done in all patients and controls. Data were entered in Excel software and were analyzed using NCSS software. All possible regression analysis was done to select the important variables to be included in the model to predict the excision of tumor with these variables. A prediction model was developed defining the binary outcome as total excision or subtotal excision as dependent variable and the morphometric data and grading of tumor as independent variables. Results: Interpetrous distance (IP) is the distance between the two petrous apices. Sigmoid distance (IS) distance is the distance between the two sigmoid points. Sigmoid point is the point at which the scalloped impression of the sigmoid sinus straightens to join the occipital bone posteriorly. SAG is the distance between the mid IP point and the mid-point on the inner wall of the occipital bone. The PM angle was 47.8±4.14 degrees (38-58), the PA angle was 42.68±4.47 degrees (34-53), the IP distance was 2.07±0.13 cm (1.5-2.8), the sagittal diameter of posterior fossa was 6.22±0.73 cm (5.1-9.8) and the intersigmoid distance was 9.45±0.73 cm (7.4-11). There was no significant gender difference in the posterior fossa morphometry between patients and controls. Inter-sigmoid distance and the petrous-apex angle were more in the Indians when compared to the European population mentioned in the Mathies and Samii study. Conclusions: The posterior fossa

  9. Cerebellar Mutism Syndrome After Posterior Fossa Surgery: A Report of Two Cases of Pilocytic Astrocytoma

    PubMed Central

    GÜNDÜZ, Hasan Burak; YASSA, Mustafa İlker Kuntay; OFLUOĞLU, Ali Ender; POSTALCI, Lütfü; EMEL, Erhan

    2013-01-01

    Cerebellar mutism is a type of syndrome including decreased speech, hypotonia, ataxia and emotional instability which occurs after posterior fossa surgery. It has been first reported by Rekate et al. and Yonemasu in 1985. It is well known that long tract signs and lower cranial nerve involvement are not seen with this syndrome and understanding is preserved. However, the pathophysiology of cerebellar mutism has not been well clarified yet. It is mainly seen in patients with medulloblastoma and brainstem involvement. In this report, we present two extraordinary cases of cerebellar mutism after posterior fossa surgery. They were considered extraordinary because their hystopathological analysis results yielded pilocytic astrocytoma which is out of the predefined risk factors.

  10. Intracranial Capillary Hemangioma in the Posterior Fossa of an Adult Male

    PubMed Central

    2016-01-01

    Intracranial capillary hemangioma (ICH) is a rare entity, with approximately 24 reported cases in the literature. There are only three reported cases of ICH in an adult male. In this case report, we describe the fourth documented case of ICH in an adult male and, to the best of our knowledge, the first ever documented case of ICH in the posterior fossa of an adult male. We also discuss its imaging appearance and differential diagnosis. PMID:27747124

  11. Posterior fossa dermoid with Klippel-Feil syndrome in a child.

    PubMed

    Ramzan, Altaf; Khursheed, Nayil; Rumana, Makhdoomi; Abrar, Wani; Ashish, Jain

    2011-09-01

    Intracranial dermoid tumors constitute a rare entity. Their association with Klippel-Feil anomaly is all the more rare. These lesions, if associated with dermal sinuses, receive attention when a patient presents with features of central nervous system infection. We describe a 5-year-old girl who presented with purulent discharge from an occipital dermal sinus with an infected posterior fossa dermoid associated with cerebellar abscesses and characteristic Klippel-Feil anomaly.

  12. The use of wavelet filters for reducing noise in posterior fossa Computed Tomography images

    SciTech Connect

    Pita-Machado, Reinado; Perez-Diaz, Marlen Lorenzo-Ginori, Juan V. Bravo-Pino, Rolando

    2014-11-07

    Wavelet transform based de-noising like wavelet shrinkage, gives the good results in CT. This procedure affects very little the spatial resolution. Some applications are reconstruction methods, while others are a posteriori de-noising methods. De-noising after reconstruction is very difficult because the noise is non-stationary and has unknown distribution. Therefore, methods which work on the sinogram-space don’t have this problem, because they always work over a known noise distribution at this point. On the other hand, the posterior fossa in a head CT is a very complex region for physicians, because it is commonly affected by artifacts and noise which are not eliminated during the reconstruction procedure. This can leads to some false positive evaluations. The purpose of our present work is to compare different wavelet shrinkage de-noising filters to reduce noise, particularly in images of the posterior fossa within CT scans in the sinogram-space. This work describes an experimental search for the best wavelets, to reduce Poisson noise in Computed Tomography (CT) scans. Results showed that de-noising with wavelet filters improved the quality of posterior fossa region in terms of an increased CNR, without noticeable structural distortions.

  13. Identifying quantitative imaging features of posterior fossa syndrome in longitudinal MRI

    PubMed Central

    Spiteri, Michaela; Windridge, David; Avula, Shivaram; Kumar, Ram; Lewis, Emma

    2015-01-01

    Abstract. Up to 25% of children who undergo brain tumor resection surgery in the posterior fossa develop posterior fossa syndrome (PFS). This syndrome is characterized by mutism and disturbance in speech. Our hypothesis is that there is a correlation between PFS and the occurrence of hypertrophic olivary degeneration (HOD) in structures within the posterior fossa, known as the inferior olivary nuclei (ION). HOD is exhibited as an increase in size and intensity of the ION on an MR image. Longitudinal MRI datasets of 28 patients were acquired consisting of pre-, intra-, and postoperative scans. A semiautomated segmentation process was used to segment the ION on each MR image. A full set of imaging features describing the first- and second-order statistics and size of the ION were extracted for each image. Feature selection techniques were used to identify the most relevant features among the MRI features, demographics, and data based on neuroradiological assessment. A support vector machine was used to analyze the discriminative features selected by a generative k-nearest neighbor algorithm. The results indicate the presence of hyperintensity in the left ION as the most diagnostically relevant feature, providing a statistically significant improvement in the classification of patients (p=0.01) when using this feature alone. PMID:26835496

  14. Transfrontal Transaqueductal, Transtrigonal, and Suboccipital Infratentorial Supracerebellar Endoscopic Fenestration of Posterior Fossa Arachnoid Cysts: Three Surgical Cases.

    PubMed

    Idris, Zamzuri; Tan, Yew Chin; Kandasamy, Regunath; Ghani, Rahman Izaini; Abdullah, Jafri Malin

    2017-03-01

    Symptomatic intracranial arachnoid cysts are commonly treated using neuroendoscopy. Cysts located within the posterior fossa may present a greater surgical challenge to the neurosurgeon due to the numerous vital neurovascular structures located within this confined space. Adding neuronavigation during endoscopy helps a neurosurgeon to visualize and utilize both anterior and posterior corridors safely to access and manage these lesions. We present three symptomatic posterior fossa arachnoid cysts that were treated successfully using minimally invasive neuronavigation-guided endoscopic neurosurgery utilizing the anterior transfrontal transaqueductal, anterior transfrontal transtrigonal, and posterior suboccipital infratentorial supracerebellar approaches.

  15. Vascular endothelial growth factor expression and bone formation in posterior glenoid fossa during stepwise mandibular advancement.

    PubMed

    Shum, Lily; Rabie, A B M; Hägg, Urban

    2004-02-01

    This study assessed the amount of vascular endothelial growth factor (VEGF) expression and related the findings to new bone formation in the posterior glenoid fossa during stepwise mandibular advancement. A total of 250 female Sprague-Dawley rats, 35 days old, were randomly divided into 10 groups, each including 5 control and 20 experimental rats. Within each group, 10 experimental rats were fitted with functional appliances with a 1-step advancement of 3.5 mm. Another 10 were fitted with stepwise appliances with an initial advancement of 2 mm and a subsequent increase to 3.5 mm on day 30. The rats in the experimental groups were killed on days 3, 7, 14, 21, 30, 33, 37, 44, 51, and 60, respectively. The matched controls were killed on the same time points. Sections (7 microm) were cut through the glenoid fossa sagittally and stained with anti-VEGF antibody. VEGF expression in the posterior glenoid fossa was evaluated with a computer-assisted image-analyzing system. Both VEGF expression and new bone formation were greater in the experimental rats than in the controls. During stepwise advancement, initial VEGF expression was less than that of 1-step advancement, but the second advancement elicited another peak on day 44. New bone formation was also less than that of 1-step advancement during early stages of stepwise advancement but then began to increase from day 37 onward. The maximum increase was observed on day 60. Stepwise advancement of the mandible delivers mechanical stimuli that produce a series of tissue responses that lead to increased vascularization and bone formation.

  16. Functional and neuropsychological late outcomes in posterior fossa tumors in children.

    PubMed

    Lassaletta, Alvaro; Bouffet, Eric; Mabbott, Donald; Kulkarni, Abhaya V

    2015-10-01

    Tumors of the posterior fossa (PF) account for up to 60 % of all childhood intracranial tumors. Over the last decades, the mortality rate of children with posterior fossa tumors has gradually decreased. While survival has been the primary objective in most reports, quality of survival increasingly appears to be an important indicator of a successful outcome. Children with a PF tumor can sustain damage to the cerebellum and other brain structures from the tumor itself, concomitant hydrocephalus, the consequences of treatment (surgery, chemotherapy, radiotherapy), or a combination of these factors. Together, these contribute to long-term sequelae in physical functioning, neuropsychological late outcomes (including academic outcome, working memory, perception and estimation of time, and selective attention, long-term neuromotor speech deficits, and executive functioning). Long-term quality of life can also be affected by endocrinological complication or the occurrence of secondary tumors. A significant proportion of survivors of PF tumors require long-term special education services and have reduced rates of high school graduation and employment. Interventions to improve neuropsychological functioning in childhood PF tumor survivors include (1) pharmacological interventions (such as methylphenidate, modafinil, or donepezil), (2) cognitive remediation, and (3) home-based computerized cognitive training. In order to achieve the best possible outcome for survivors, and ultimately minimize long-term complications, new interventions must be developed to prevent and ameliorate the neuro-toxic effects experienced by these children.

  17. Late effects of treatment on the intelligence of children with posterior fossa tumors

    SciTech Connect

    Duffner, P.K.; Cohen, M.E.; Thomas, P.

    1983-01-15

    This retrospective pilot study was undertaken to evaluate the late effects of treatment on intelligence in a population of children with posterior fossa tumors. Ten children with posterior fossa tumors treated with radiation and chemotherapy received intellectual evaluations at least one year following diagnosis. Six children had medulloblastomas, one child had a fourth ventricular ependymoma, two children had brainstem gliomas, and one child had a recurrent cerebellar astrocytoma. Children with supratentorial tumors were specifically excluded from the study in order to eliminate the possible influence of the tumor on intellectual functioning. Four children had had intelligence testing in school prior to treatment of their tumor. In each case results following treatment revealed a deterioration of full scale IQ of at least 25 points. Six children did not have prior testing; of these, two had IQ's less than 20. Overall, 50% of the patients had IQ's of less than 80 and 20% had IQ's of greater than 100. Furthermore, four children with normal intelligence (IQ greater than 80) have learning problems requiring special classes. Thus, of the ten children evaluated, all have either dementia, learning disabilities, or evidence of intellectual retardation. This study suggests that aggressive treatment of children with brain tumors may improve survivals but may be associated with significant long-term disabilities.

  18. Pathology, treatment and management of posterior fossa brain tumors in childhood

    SciTech Connect

    Bonner, K.; Siegel, K.R.

    1988-04-01

    Brain tumors are the second most common childhood malignancy. Between 1975 and 1985, 462 newly diagnosed patients were treated at the Children's Hospital of Philadelphia; 207 (45%) tumors arose in the posterior fossa and 255 (55%) appeared supratentorially. A wide variety of histological subtypes were seen, each requiring tumor-specific treatment approaches. These included primitive neuroectodermal tumor (n = 86, 19%), astrocytoma (n = 135, 30%), brainstem glioma (n = 47, 10%), anaplastic astrocytoma (n = 32, 7%), and ependymoma (n = 30, 6%). Because of advances in diagnostic abilities, surgery, radiotherapy, and chemotherapy, between 60% and 70% of these patients are alive today. Diagnostic tools such as computed tomography and magnetic resonance imaging allow for better perioperative management and follow-up, while the operating microscope, CO/sub 2/ laser, cavitron ultrasonic aspirator and neurosurgical microinstrumentation allow for more extensive and safer surgery. Disease specific treatment protocols, utilizing radiotherapy and adjuvant chemotherapy, have made survival common in tumors such as medulloblastoma. As survival rates increase, cognitive, endocrinologic and psychologic sequelae become increasingly important. The optimal management of children with brain tumors demands a multidisciplinary approach, best facilitated by a neuro-oncology team composed of multiple subspecialists. This article addresses incidence, classification and histology, clinical presentation, diagnosis, pre-, intra- and postoperative management, long-term effects and the team approach in posterior fossa tumors in childhood. Management of specific tumor types is included as well. 57 references.

  19. Multifocal melanocytoma of the posterior fossa and subcutaneous scalp in the absence of neurocutaneous melanosis

    PubMed Central

    Pierson, Matt; Marwaha, Nitin; Guzman, Miguel; Mikulec, Anthony A.; Coppens, Jeroen R.

    2016-01-01

    Background: Primary leptomeningeal melanocytic neoplasms of the central nervous system are rare. Multifocal lesions typically occur in the setting of cutaneous melanosis. We present the first report of a posterior fossa melanocytoma and subcutaneous melanocytoma of intermediate grade in the absence of cutaneous melanosis. Case Description: We present the case of a 22-year-old male with decreased hearing on the right side, ataxia, nausea, vomiting and a scalp mass. Magnetic resonance imaging (MRI) demonstrated occipital and cerebellopontine (CP) angle masses. The patient underwent gross total resection of the scalp mass and subtotal resection of the CP angle mass. Pathologic examination revealed melanocytoma with intermediate grade. The patient underwent stereotactic radiosurgery to the residual CP angle tumor. This case represents, to the author's knowledge, the first report associating a posterior fossa melanocytoma with a subcutaneous melanocytoma of intermediate grade in the absence of cutaneous melanosis. Conclusion: This case introduces the first report of a new variant of multifocal melanocytoma which is not confined to the central nervous system. PMID:27656317

  20. Extramedullary plasmacytoma presenting as a solitary mass in the intracranial posterior fossa.

    PubMed

    Daghighi, Mohammad Hossein; Poureisa, Masoud; Shimia, Mohammad; Mazaheri-Khamene, Ramin; Daghighi, Shadi

    2012-11-01

    A patient with a 3-month history of headache refractory to pain medication was admitted. The CT scan and MRI showed evidence of a posterior fossa mass. This was pathologically confirmed as an extra medullary plasmacytoma (EMP). He had a pathologic fracture of the left humerus 7 years ago while the radiologist was unaware at the time of diagnosis. A solitary bone plasmacytoma (SBP) was the cause of the pathologic fracture. This report includes the first description of MRI findings in a patient with a rare-incidence intracranial solitary extra medullary plasmacytoma (SEP) in Iran. There is a striking similarity between the features of intracranial SEP and meningiomas. Intracranial SEP, although rare, should be included in the differential diagnosis of brain tumors in areas where meningiomas commonly arise. The MRI findings and differential diagnosis of plasmacytoma are reviewed. Before this case report, only few cases have been reported in the literature. Nonetheless, this is the first report of posterior fossa EMP from Iran.

  1. Extramedullary Plasmacytoma Presenting as a Solitary Mass in the Intracranial Posterior Fossa

    PubMed Central

    Daghighi, Mohammad Hossein; Poureisa, Masoud; Shimia, Mohammad; Mazaheri-Khamene, Ramin; Daghighi, Shadi

    2012-01-01

    A patient with a 3-month history of headache refractory to pain medication was admitted. The CT scan and MRI showed evidence of a posterior fossa mass. This was pathologically confirmed as an extra medullary plasmacytoma (EMP). He had a pathologic fracture of the left humerus 7 years ago while the radiologist was unaware at the time of diagnosis. A solitary bone plasmacytoma (SBP) was the cause of the pathologic fracture. This report includes the first description of MRI findings in a patient with a rare-incidence intracranial solitary extra medullary plasmacytoma (SEP) in Iran. There is a striking similarity between the features of intracranial SEP and meningiomas. Intracranial SEP, although rare, should be included in the differential diagnosis of brain tumors in areas where meningiomas commonly arise. The MRI findings and differential diagnosis of plasmacytoma are reviewed. Before this case report, only few cases have been reported in the literature. Nonetheless, this is the first report of posterior fossa EMP from Iran. PMID:23408237

  2. Anatomical Factors Influencing Selective Vestibular Neurectomy: A Comparison of Posterior Fossa Approaches

    PubMed Central

    Master, Adam N.; Flores, Jose M.; Gardner, L. Gale; Cosetti, Maura K.

    2015-01-01

    Objectives To identify measurable anatomical factors that may guide the surgical approach for posterior fossa selective vestibular neurectomy (SVN) and predict identification of the vestibulocochlear cleavage (VCC) plane. Study Design Dissection of fixed cadaveric heads through retrolabyrinthine and retrosigmoid-internal auditory canal (RSG-IAC) approaches with measurement of landmarks. Setting Cadaveric dissection model. Main Outcome Measures Area of the Trautmann triangle (TT) and the distance from the posterior semicircular canal to the anterior border of the sigmoid along the posterior Donaldson line (pDL). VCC planes from each approach were calculated and compared. Results Overall mean pDL was 8.53 mm (range: 5–11.5 mm); mean TT area was 124 mm2 (range: 95–237 mm2). The VCC was identified in 63% of ears through the retrolabyrinthine (RVN) approach alone, whereas 37% of ears required the RSG-IAC approach. In ears requiring IAC dissection, the VCC was found within 1 to 2 mm distal to the porus. The pDL (p < 0.05) and area of TT (p < 0.05) were significantly larger in the RVN group compared with the RSG-IAC group. Conclusion Ears amenable to the RVN approach had a greater pDL and TT area. These anatomical measurements may have a role in surgical planning and the choice of approach for SVN. PMID:26949584

  3. Incidence, Risks, and Sequelae of Posterior Fossa Syndrome in Pediatric Medulloblastoma

    SciTech Connect

    Korah, Mariam P.; Esiashvili, Natia; Mazewski, Claire M.; Hudgins, Roger J.; Tighiouart, Mourad; Janss, Anna J.; Schwaibold, Frederick P.; Crocker, Ian R.; Curran, Walter J.; Marcus, Robert B.

    2010-05-01

    Purpose: To investigate the incidence, risks, severity, and sequelae of posterior fossa syndrome (PFS) in children with medulloblastoma. Methods and Materials: Between 1990 and 2007, 63 children with medulloblastoma at Emory University and Children's Healthcare of Atlanta were treated with craniectomy followed by radiation. Fifty-one patients were assigned to a standard-risk group, and 12 patients were assigned to a high-risk group. Five patients had <1.5-cm{sup 2} residual tumor, 4 had >=1.5-cm{sup 2} residual tumor, and the remainder had no residual tumor. Eleven patients had disseminated disease. Patients received craniospinal irradiation at a typical dose of 23.4 Gy or 36 Gy for standard- or high-risk disease, respectively. The posterior fossa was given a total dose of 54 or 55.8 Gy. Nearly all patients received chemotherapy following cooperative group protocols. Results: Median follow-up was 7 years. PFS developed in 18 patients (29%). On univariate analysis, brainstem invasion, midline tumor location, younger age, and the absence of radiographic residual tumor were found to be predictors of PFS; the last two variables remained significant on multivariate analysis. From 1990 to 2000 and from 2001 to 2007, the proportions of patients with no radiographic residual tumor were 77% and 94%, respectively. During the same eras, the proportions of patients with PFS were 17% and 39%. Only 4 patients had complete recovery at last follow-up. Conclusions: The incidence of PFS increased in the latter study period and is proportional to more aggressive surgery. Children with midline tumors exhibiting brainstem invasion are at increased risk. With the increased incidence of PFS and the permanent morbidity in many patients, the risks and benefits of complete tumor removal in all patients need to be reexamined.

  4. Therapeutic strategy and long-term outcome of meningiomas located in the posterior cranial fossa.

    PubMed

    Matsui, Toru

    2012-01-01

    The clinical and surgical findings of 41 consecutive cases of posterior cranial fossa meningiomas operated on between January 1987 and December 2011 at Saitama Medical Center/Saitama Medical University were reviewed. The 31 female and 10 male patients were aged from 19 to 74 years (mean 54 years). The tumors were located in the petroclival (N=15), craniovertebral junction (N=6), lateral tentorial (N=12), and cerebellopontine angle (N=8) regions. Mean tumor equivalent diameter was 4.3 cm (range 2-9 cm). Head pain (46.3%) and gait disturbance (26.8%) were the most common presenting symptoms, and cranial neuropathies were the most common neurological signs on admission. Mean preoperative performance status (Karnofsky scale) was 83% (range 40-100%). Surgical approaches to these tumors included presigmoidal transpetrosal, retrosigmoidal, transcondylar, and combined approaches. In 4 cases, a staged procedure was performed. Gross total resection was achieved in 85.4% of patients, and subtotal/partial resection in 12.2%. Surgical mortality was 2.4% and complications were encountered in 11 patients (26.8%) including temporary neurological deficits in 4 patients. The mean follow-up period was 8.2 years, ranging from 1 to 24 years, and the mean performance status of patients at 12 months after the last surgery was 92% (range 0-100%). Recurrence or progression of disease was found in 9.8% of cases. Postoperative adjuvant therapy was performed in 6 cases. My experience suggests that although posterior cranial fossa meningiomas represent a continuing challenge for contemporary neurosurgeons, such tumors may be completely or subtotally removed with low rate of mortality and acceptable morbidity, allowing most of these patients to achieve good outcome in long-term follow up.

  5. The complex arrangement of an "aorto-jejunal paraduodenal" fossa, as revealed by dissection of human posterior parietal peritoneum.

    PubMed

    Barberini, Fabrizio; Zani, Augusto; Ripani, Maurizio; Di Nitto, Valentina; Brunone, Francesca

    2007-01-01

    Peritoneal fossae derive from normal or anomalous coalescence of the peritoneum during fetal development, or from the course of retroperitoneal vessels. Clinically, internal abdominal hernias may be housed inside these fossae. In this report from an autopsy, a singular peritoneal fossa was delimited superiorly by an arcuate serous fold, raised up by the inferior mesenteric vein, and infero-posteriorly by two (right and left) avascular folds, extending from the abdominal aorta to the jejunum. The right fold reached the duodeno-jejunal flexure, which was located on the right side of the aorta. The left fold subdivided into two, anterior and posterior, secondary folds. The anterior fold reached the superior edge of the first jejunal loop, and the posterior fold turned medially to connect with the inferior edge of the proximal limb of the same loop. This fossa consisted of three recesses: superior, Located behind the subserous vascular arch, antero-inferior and postero-inferior, separated by interposition of the left posterior secondary fold, between the jejunum and aorta. The complex arrangement of this fossa suggests that it might have originated from a coalescence arising beyond the duodeno-jejunal flexure and including the first jejunal loop, and from the subserous course of the inferior mesenteric vein. Because of displacement to the right of the flexure, processes of coalescence in a location normally occupied by the ascending duodenum might have occurred in a similar pattern for the jejunum, involving the mesoduodenum and the proximal part of the mesentery. Labyrinthine fossae like this might cause strangulation of internal abdominal hernias and hinder intraoperative maneuvers.

  6. Giant cyst of the cavum septi pellucidi and cavum Vergae with posterior cranial fossa extension: case report.

    PubMed

    Bayar, M A; Gökçek, C; Gökçek, A; Edebali, N; Buharali, Z

    1996-05-01

    The cavum septi pellucidi (CSP) and cavum Vergae (CV) are frequently seen in premature and term infants. These cavities rarely enlarge and become symptomatic we describe a giant CSP and CV cyst in an 18-month-old boy, extending to the posterior cranial fossa and causing hydrocephalus. The literature is reviewed, and the MRI and CT findings of the case are reported.

  7. I-gel Laryngeal Mask Airway Combined with Tracheal Intubation Attenuate Systemic Stress Response in Patients Undergoing Posterior Fossa Surgery

    PubMed Central

    Tang, Chaoliang; Chai, Xiaoqing; Kang, Fang; Huang, Xiang; Hou, Tao; Tang, Fei; Li, Juan

    2015-01-01

    Background. The adverse events induced by intubation and extubation may cause intracranial hemorrhage and increase of intracranial pressure, especially in posterior fossa surgery patients. In this study, we proposed that I-gel combined with tracheal intubation could reduce the stress response of posterior fossa surgery patients. Methods. Sixty-six posterior fossa surgery patients were randomly allocated to receive either tracheal tube intubation (Group TT) or I-gel facilitated endotracheal tube intubation (Group TI). Hemodynamic and respiratory variables, stress and inflammatory response, oxidative stress, anesthesia recovery parameters, and adverse events during emergence were compared. Results. Mean arterial pressure and heart rate were lower in Group TI during intubation and extubation (P < 0.05 versus Group TT). Respiratory variables including peak airway pressure and end-tidal carbon dioxide tension were similar intraoperative, while plasma β-endorphin, cortisol, interleukin-6, tumor necrosis factor-alpha, malondialdehyde concentrations, and blood glucose were significantly lower in Group TI during emergence relative to Group TT. Postoperative bucking and serious hypertensions were seen in Group TT but not in Group TI. Conclusion. Utilization of I-gel combined with endotracheal tube in posterior fossa surgery patients is safe which can yield more stable hemodynamic profile during intubation and emergence and lower inflammatory and oxidative response, leading to uneventful recovery. PMID:26273146

  8. Role of Cerebellum in Fine Speech Control in Childhood: Persistent Dysarthria after Surgical Treatment for Posterior Fossa Tumour

    ERIC Educational Resources Information Center

    Morgan, A. T.; Liegeois, F.; Liederkerke, C.; Vogel, A. P.; Hayward, R.; Harkness, W.; Chong, K.; Vargha-Khadem, F.

    2011-01-01

    Dysarthria following surgical resection of childhood posterior fossa tumour (PFT) is most commonly documented in a select group of participants with mutism in the acute recovery phase, thus limiting knowledge of post-operative prognosis for this population of children as a whole. Here we report on the speech characteristics of 13 cases seen…

  9. Role of the cerebellum in the neurocognitive sequelae of treatment of tumours of the posterior fossa: an update.

    PubMed

    Cantelmi, David; Schweizer, Tom A; Cusimano, Michael D

    2008-06-01

    The lengthened survival of patients with tumours of the posterior fossa has brought awareness of the neurocognitive deficits present in this patient population. In the past, these deficits were thought to be caused by radiotherapy damaging supratentorial structures known to be responsible for cognitive processing. This notion led to the development of new treatment protocols to restrict damage to supratentorial regions by decreasing the radiation dose and the irradiated volume. However, these treatment protocols have only resulted in marginal improvements, sometimes at the expense of long-term survival. Moreover, the current published work reports that non-irradiated patients with tumours of the posterior fossa exhibit similar cognitive impairments to irradiated patients. The growth and treatment of tumours of the posterior fossa also damage infratentorial structures, including the cerebellum. Findings from anatomical, clinical, and neuroimaging studies support a role for the cerebellum in cognitive functions similar to those impaired in patients with a tumour of the posterior fossa. Despite these findings, research focused on the treatment of these patients and on decreasing their cognitive impairments either ignores that the cerebellum has been implicated in non-motor functions or argues against the possibility that damage to the cerebellum might result in cognitive sequelae. Future studies need to address the possibility that the cognitive impairments of patients with tumours of the posterior fossa might be determined by a combination of factors, including damage to the cerebellum. Recognition of the important cognitive contributions of the cerebellum might lead to improved cognitive outcome and quality of life for this patient population.

  10. Posterior fossa syndrome with a large inflammatory ponto-mesencephalic lesion.

    PubMed

    Breit, S; Keserü, B; Nyffeler, T; Sturzenegger, M; Krestel, H

    2017-02-01

    Demonstration of a posterior fossa syndrome (PFS) in a 32-year-old male patient with clinically isolated syndrome which subsequently developed into relapsing-remitting Multiple Sclerosis. The patient suffered from double vision, coordination problems including unsteady gait and atactic dysarthria, concentration difficulties, as well as adynamia and impaired decision making. The patient clinically presented a cerebellar and dysexecutive syndrome. Cerebral magnetic resonance imaging (MRI) revealed a contrast enhancing ponto-mesencephalic lesion with a volume of 4.8cm(3). Neuropsychological tests showed pronounced executive dysfunctions, reduced visuoconstructive skills, attentional deficits, echolalia, and non-fluent speech production. After cortisone and plasmapheresis, the cerebellar syndrome improved but manual fine motor skills and executive dysfunctions persisted. After three months, symptoms remitted except for a slight gait imbalance. After six months, neuropsychological tests were normal except for a moderate attention deficit. MRI revealed a clear regression of the ponto-mesencephalic lesion to a volume of 2.4cm(3) without contrast enhancement. This case report intends to provide an overview of the symptomatology and etiology of PFS and offers new insights into its pathomechanism demonstrating a pontine disconnection syndrome caused by a large demyelinating plaque.

  11. Declarative and procedural learning in children and adolescents with posterior fossa tumours

    PubMed Central

    Quintero-Gallego, Eliana A; Gómez, Carlos M; Casares, Encarnación Vaquero; Márquez, Javier; Pérez-Santamaría, Fco Javier

    2006-01-01

    Background This quasi-experimental study was designed to assess two important learning types – procedural and declarative – in children and adolescents affected by posterior fossa tumours (astrocytoma vs. medulloblastoma), given that memory has an important impact on the child's academic achievement and personal development. Methods We had three groups: two clinical (eighteen subjects) and one control (twelve subjects). The learning types in these groups were assessed by two experimental tasks evaluating procedural-implicit and declarative memory. A Serial Reaction-Time Task was used to measure procedural sequence learning, and the Spanish version [1] of the California Verbal Learning Test-Children's Version- CVLT- [2] to measure declarative-explicit learning. The learning capacity was assessed considering only the blocks that represent learning, and were compared with MANOVA in clinical and normal subjects. The Raven, simple reaction-time, finger-tapping test, and grooved pegboard tests were used to assess the overall functioning of subjects. The results were compared with those from a control group of the same age, and with Spanish norm-referenced tools where available Results The results indicate the absence of procedural-implicit learning in both clinical groups, whereas declarative-explicit learning is maintained in both groups. Conclusion The clinical groups showed a conservation of declarative learning and a clear impairment of procedural learning. The results support the role of the cerebellum in the early phase of procedural learning. PMID:16539720

  12. Tension pneumocephalus after posterior fossa craniotomy: report of four additional cases and review of postoperative pneumocephalus.

    PubMed

    Toung, T; Donham, R T; Lehner, A; Alano, J; Campbell, J

    1983-02-01

    Four cases of tension pneumocephalus after either posterior fossa craniotomy or translabyrinthine resection of acoustic neuroma with or without nitrous oxide anesthesia are described. Three of the operations were performed with the patient in the sitting position, and one was done with the patient in the lateral position. Of the three cases operated in the sitting position, no nitrous oxide was used at any time during anesthesia in one. Two patients failed to regain consciousness after the termination of anesthesia, and the other two developed the sudden onset of neurological symptoms 1 to 1.5 hours after the operation. In all cases computed tomography disclosed a large subdural collection of air. Re-exploration of the surgical wound or twist drill aspiration of the subdural air resulted in prompt recovery of neurological status in three patients, whereas the other patient's neurological status improved gradually without any specific treatment. The role played by nitrous oxide, the mechanisms by which air enters the intracranial space, the contributory factors, and the predisposing surgical conditions of tension pneumocephalus are reviewed and discussed. Dependent drainage of the cerebrospinal fluid, especially in a patient with coexisting hydrocephalus, seems to be the most important factor for the development of this complication.

  13. Longitudinal MRI assessment: the identification of relevant features in the development of Posterior Fossa Syndrome in children

    NASA Astrophysics Data System (ADS)

    Spiteri, M.; Lewis, E.; Windridge, D.; Avula, S.

    2015-03-01

    Up to 25% of children who undergo brain tumour resection surgery in the posterior fossa develop posterior fossa syndrome (PFS). This syndrome is characterised by mutism and disturbance in speech. Our hypothesis is that there is a correlation between PFS and the occurrence of hypertrophic olivary degeneration (HOD) in lobes within the posterior fossa, known as the inferior olivary nuclei (ION). HOD is exhibited as an increase in size and intensity of the ION on an MR image. Intra-operative MRI (IoMRI) is used during surgical procedures at the Alder Hey Children's Hospital, Liver- pool, England, in the treatment of Posterior Fossa tumours and allows visualisation of the brain during surgery. The final MR scan on the IoMRI allows early assessment of the ION immediately after the surgical procedure. The longitudinal MRI data of 28 patients was analysed in a collaborative study with Alder Hey Children's Hospital, in order to identify the most relevant imaging features that relate to the development of PFS, specifically related to HOD. A semi-automated segmentation process was carried out to delineate the ION on each MRI. Feature selection techniques were used to identify the most relevant features amongst the MRI data, demographics and clinical data provided by the hospital. A support vector machine (SVM) was used to analyse the discriminative ability of the selected features. The results indicate the presence of HOD as the most efficient feature that correlates with the development of PFS, followed by the change in intensity and size of the ION and whether HOD occurred bilaterally or unilaterally.

  14. An unusual and spectacular case of spindle cell lipoma of the posterior neck invading the spinal cervical canal and posterior cranial fossa.

    PubMed

    Petit, Damien; Menei, Philippe; Fournier, Henri-Dominique

    2011-11-01

    The authors describe the first case of spindle cell lipoma of the posterior neck invading the upper cervical spinal canal and the posterior cranial fossa. Spindle cell lipoma is an extremely rare variant of benign lipoma. It usually occurs as a solitary subcutaneous well-circumscribed lesion in the posterior neck or shoulders of adult men. Local aggressiveness is unusual. This 61-year-old man presented with an increased left cerebellar syndrome and headaches. He also had a posterior neck tumefaction, which had been known about for a long time. Computed tomography and MR imaging studies revealed a voluminous mass extending to the upper cervical canal and posterior cranial fossa and eroding the neighboring bones. The lesion was well delimited, and contrast enhancement was intense and heterogeneous. The tumor, which had initially developed under the muscles of the posterior neck, was totally resected. Histological assessment revealed numerous fat cells with spindle cells secreting collagen. The large size of the tumor and the submuscular location, bone erosion, and compression of the CNS were unusual in this rare subtype of benign adipose tumor. Its presentation could simulate a sarcoma.

  15. Inauguration of pediatric neurosurgery by Harvey W. Cushing: his contributions to the surgery of posterior fossa tumors in children. Historical vignette.

    PubMed

    Cohen-Gadol, Aaron A; Spencer, Dennis D

    2004-02-01

    Development of posterior fossa surgery remains Harvey Cushing's hallmark contribution to pediatric neurosurgery. During the era before Cushing, posterior fossa lesions were considered inoperable, and only osseous decompressive surgery was offered. The evolution of Cushing's surgical expertise from subtemporal decompressions to total extirpation of vascular fourth ventricular tumors, combined with a dramatic decrease in his operative mortality rate, reflects the maturation of modern neurosurgical techniques. A comprehensive review of the medical records of Cushing's pediatric patients treated between 1912 and 1932 revealed that procedures such as lateral ventricular puncture (to decrease cerebellar herniation), transvermian approach to midline tumors, and electrocoagulation were the key factors punctuating the path to his pioneering achievements in posterior fossa surgery. The outcome of such operations was improved by his recognition of the importance of tumor mural nodule in cyst recurrence, as well as elucidation of the histogenesis of pediatric posterior fossa tumors to tailor treatment including radiotherapy.

  16. Factors associated with spinal fusion after posterior fossa decompression in pediatric patients with Chiari I malformation and scoliosis.

    PubMed

    Mackel, Charles E; Cahill, Patrick J; Roguski, Marie; Samdani, Amer F; Sugrue, Patrick A; Kawakami, Noriaki; Sturm, Peter F; Pahys, Joshua M; Betz, Randal R; El-Hawary, Ron; Hwang, Steven W

    2016-12-01

    OBJECTIVE The authors performed a study to identify clinical characteristics of pediatric patients diagnosed with Chiari I malformation and scoliosis associated with a need for spinal fusion after posterior fossa decompression when managing the scoliotic curve. METHODS The authors conducted a multicenter retrospective review of 44 patients, aged 18 years or younger, diagnosed with Chiari I malformation and scoliosis who underwent posterior fossa decompression from 2000 to 2010. The outcome of interest was the need for spinal fusion after decompression. RESULTS Overall, 18 patients (40%) underwent posterior fossa decompression alone, and 26 patients (60%) required a spinal fusion after the decompression. The mean Cobb angle at presentation and the proportion of patients with curves > 35° differed between the decompression-only and fusion cohorts (30.7° ± 11.8° vs 52.1° ± 26.3°, p = 0.002; 5 of 18 vs 17 of 26, p = 0.031). An odds ratio of 1.0625 favoring a need for fusion was established for each 1° of increase in Cobb angle (p = 0.012, OR 1.0625, 95% CI 1.0135-1.1138). Among the 14 patients older than 10 years of age with a primary Cobb angle exceeding 35°, 13 (93%) ultimately required fusion. Patients with at least 1 year of follow-up whose curves progressed more 10° after decompression were younger than those without curve progression (6.1 ± 3.0 years vs 13.7 ± 3.2 years, p = 0.001, Mann-Whitney U-test). Left apical thoracic curves constituted a higher proportion of curves in the decompression-only group (8 of 16 vs 1 of 21, p = 0.002). CONCLUSIONS The need for fusion after posterior fossa decompression reflected the curve severity at clinical presentation. Patients presenting with curves measuring > 35°, as well as those greater than 10 years of age, may be at greater risk for requiring fusion after posterior fossa decompression, while patients less than 10 years of age may require routine monitoring for curve progression. Left apical thoracic curves

  17. Changes in cerebrospinal fluid flow assessed using intraoperative MRI during posterior fossa decompression for Chiari malformation.

    PubMed

    Bond, Aaron E; Jane, John A; Liu, Kenneth C; Oldfield, Edward H

    2015-05-01

    OBJECT The authors completed a prospective, institutional review board-approved study using intraoperative MRI (iMRI) in patients undergoing posterior fossa decompression (PFD) for Chiari I malformation. The purpose of the study was to examine the utility of iMRI in determining when an adequate decompression had been performed. METHODS Patients with symptomatic Chiari I malformations with imaging findings of obstruction of the CSF space at the foramen magnum, with or without syringomyelia, were considered candidates for surgery. All patients underwent complete T1, T2, and cine MRI studies in the supine position preoperatively as a baseline. After the patient was placed prone with the neck flexed in position for surgery, iMRI was performed. The patient then underwent a bone decompression of the foramen magnum and arch of C-1, and the MRI was repeated. If obstruction was still present, then in a stepwise fashion the patient underwent dural splitting, duraplasty, and coagulation of the tonsils, with an iMRI study performed after each step guiding the decision to proceed further. RESULTS Eighteen patients underwent PFD for Chiari I malformations between November 2011 and February 2013; 15 prone preincision iMRIs were performed. Fourteen of these patients (93%) demonstrated significant improvement of CSF flow through the foramen magnum dorsal to the tonsils with positioning only. This improvement was so notable that changes in CSF flow as a result of the bone decompression were difficult to discern. CONCLUSIONS The authors observed significant CSF flow changes when simply positioning the patient for surgery. These results put into question intraoperative flow assessments that suggest adequate decompression by PFD, whether by iMRI or intraoperative ultrasound. The use of intraoperative imaging during PFD for Chiari I malformation, whether by ultrasound or iMRI, is limited by CSF flow dynamics across the foramen magnum that change significantly when the patient is

  18. Torticollis secondary to posterior fossa and cervical spinal cord tumors: report of five cases and literature review.

    PubMed

    Kumandaş, Sefer; Per, Hüseyin; Gümüş, Hakan; Tucer, Bülent; Yikilmaz, Ali; Kontaş, Olgun; Coşkun, Abdülhakim; Kurtsoy, Ali

    2006-10-01

    Torticollis is either congenital or acquired in childhood. Acquired torticollis is not a diagnosis but rather a sign of an underlying disorder. The causes of acquired torticollis include ligamentous, muscular, osseous, ocular, psychiatric, and neurologic disorders and may be a symptom of significant abnormalities of the spinal cord and brain, such as spinal syrinx or central nervous system neoplasia. Torticollis is rarely considered to be an initial clinical presentation of posterior fossa and cervical spinal cord tumors. We report five cases of pediatric tumors with torticollis at the onset: an astrocytoma originating from the medulla oblongata, another presumptive astrocytoma of the spinal cord located between C1 and C6 cervical vertebrae (not operated), an ependymoma located throughout the whole cervical spinal cord extending into the bulbomedullary junction, an astrocytoma originating from the bulbus and extending into the posterior fossa, and another case of a eosinophilic granuloma located extradurally through the anterior and posterior portions of the vertebral bodies from C3 to C7 producing the collapse of the sixth cervical vertebra. All five cases were seen in children, aged between 3 and 12 years. All these cases reflect the misinterpretation of this neurological sign and the lack of association with the possibility of spinal or posterior fossa tumor. This delay in the diagnosis of these diseases led to progressive neurological deterioration and to the increase in the tumor size, which made surgical intervention difficult and the prognosis unfavorable. Although torticollis secondary to tumors is rarely seen, it is necessary to be kept in mind in the differential diagnosis.

  19. Endoscopic approach-routes in the posterior fossa cisterns through the retrosigmoid keyhole craniotomy: an anatomical study.

    PubMed

    Kurucz, Peter; Baksa, Gabor; Patonay, Lajos; Thaher, Firas; Buchfelder, Michael; Ganslandt, Oliver

    2016-11-10

    Endoscopy in cerebellopontine angle surgery is an increasingly used technique. Despite of its advantages, the shortcomings arising from the complex anatomy of the posterior fossa are still preventing its widespread use. To overcome these drawbacks, the goal of this study was to define the anatomy of different endoscopic approaches through the retrosigmoid craniotomy and their limitations by surgical windows. Anatomical dissections were performed on 25 fresh human cadavers to describe the main approach-routes. Surgical windows are spaces surrounded by neurovascular structures acting as a natural frame and providing access to deeper structures. The approach-routes are trajectories starting at the craniotomy and pointing to the lesion, passing through certain windows. Twelve different windows could be identified along four endoscopic approach-routes. The superior route provides access to the structures of the upper pons, lower mesencephalon, and the upper neurovascular complex through the suprameatal, superior cerebellar, and infratrigeminal windows. The supratentorial route leads to the basilar tip and some of the suprasellar structures via the ipsi- and contralateral oculomotor and dorsum sellae windows. The central endoscopic route provides access to the middle pons and the middle neurovascular complex through the inframeatal, AICA, and basilar windows. The inferior endoscopic route is the pathway to the medulla oblongata and the lower neurovascular complex through the accessory, hypoglossal, and foramen magnum windows. The anatomy and limitations of each surgical windows were described in detail. These informations are essential for safe application of endoscopy in posterior fossa surgery through the retrosigmoid approach.

  20. Posterior fossa decompression with tonsillectomy in 104 cases of basilar impression, Chiari malformation and/or syringomyelia.

    PubMed

    da Silva, José Alberto Gonçalves; dos Santos, Adailton Arcanjo; Melo, Luiz Ricardo Santiago; de Araújo, Antônio Fernandes; Regueira, Giseuda Pessoa

    2011-10-01

    The prime objective in the surgical treatment of basilar impression (BI), Chiari malformation (CM) and/or syringomyelia (SM) is based on the restoration of the normal cerebrospinal fluid (CSF) dynamics at the craniovertebral junction through the creation of a large artificial cisterna magna. A small suboccipital craniectomy has been emphasized to avoid caudal migration of the hindbrain structures into the vertebral canal. Nevertheless, the results showed downward migration of the hindbrain related to that type of craniectomy. The authors present, otherwise, the results of 104 cases of BI, CM and/or SM, whose surgical treatment was characterized by a large craniectomy with the patient in the sitting position, tonsillectomy, large opening of the fourth ventricle and duraplasty with creation of a large artificial cisterna magna. A significant upward migration of the posterior fossa structures was detected by postoperative magnetic resonance imaging.

  1. Intraoperative somatosensory evoked potential recovery following opening of the fourth ventricle during posterior fossa decompression in Chiari malformation: case report.

    PubMed

    Grossauer, Stefan; Koeck, Katharina; Vince, Giles H

    2015-03-01

    The most appropriate surgical technique for posterior fossa decompression in Chiari malformation (CM) remains a matter of debate. Intraoperative electrophysiological studies during posterior fossa decompression of Type I CM (CM-I) aim to shed light on the entity's pathomechanism as well as on the ideal extent of decompression. The existing reports on this issue state that significant improvement in conduction occurs after craniotomy in all cases, but additional durotomy contributes a further improvement in only a minority of cases. This implies that craniotomy alone might suffice for clinical improvement without the need of duraplasty or even subarachnoid manipulation at the level of the craniocervical junction. In contrast to published data, the authors describe the case of a 32-year-old woman who underwent surgery for CM associated with extensive cervicothoracic syringomyelia and whose intraoperative somatosensory evoked potentials (SSEPs) did not notably improve after craniotomy or following durotomy; rather, they only improved after opening of the fourth ventricle and restoration of CSF flow through the foramen of Magendie. Postoperatively, the patient recovered completely from her preoperative neurological deficits. To the authors' knowledge, this is the first report of significant SSEP recovery after opening the fourth ventricle in the decompression of a CM-I. The electrophysiological and operative techniques are described in detail and the findings are discussed in the light of available literature. The authors conclude that there might be a subset of CM-I patients who require subarachnoid dissection at the level of the craniocervical junction to benefit clinically. Prospective studies with detailed electrophysiological analyses seem warranted to answer the question regarding the best surgical approach in CM-I decompression.

  2. [A Case of Ruptured Internal Carotid-Posterior Communicating Artery Aneurysm Associated with Acute Subdural Hematoma, Extending from the Interhemispheric Space to the Posterior Fossa].

    PubMed

    Otsuka, Hiroaki; Fukuda, Yuhtaka; Yoshimura, Shouta; Somagawa, Chika; Hiu, Takeshi; Ono, Tomonori; Ushijima, Ryujirou; Toda, Keisuke; Tsutsumi, Keisuke

    2016-06-01

    A 69-year-old woman was admitted to our hospital because of a sudden severe headache without a history of head trauma. CT and MRI revealed an acute subdural hematoma (ASDH) extending from the right interhemispheric space to the posterior fossa bilaterally, with a small amount of subarachnoid hemorrhage that was predominantly localized to the left side of the basal cistern. CT angiogram demonstrated a long protruding ruptured aneurysm at the junction of the right internal carotid and posterior communicating arteries (IC/PC AN) with a posteroinferior projection, associated with a small bleb located near the tentorial edge close to the ipsilateral posterior clinoid process, for which she received clipping surgery. Though rare, IC/PC AN could cause pure or nearly pure ASDH in the above-mentioned distribution. Therefore, in patients with such ASDH, especially without a history of head injury or precise information regarding the situation at the time of onset, urgent imaging evaluation and early intervention are essential to prevent devastating re-rupture events.

  3. Role of cerebellum in fine speech control in childhood: persistent dysarthria after surgical treatment for posterior fossa tumour.

    PubMed

    Morgan, A T; Liégeois, F; Liederkerke, C; Vogel, A P; Hayward, R; Harkness, W; Chong, K; Vargha-Khadem, F

    2011-05-01

    Dysarthria following surgical resection of childhood posterior fossa tumour (PFT) is most commonly documented in a select group of participants with mutism in the acute recovery phase, thus limiting knowledge of post-operative prognosis for this population of children as a whole. Here we report on the speech characteristics of 13 cases seen long-term after surgical treatment for childhood PFT, unselected for the presence of post-operative mutism (mean time post-surgery=6y10m, range 1;4-12;6 years, two had post-operative mutism), and examine factors affecting outcome. Twenty-six age- and sex- matched healthy controls were recruited for comparison. Participants in both groups had speech assessments using detailed perceptual and acoustic methods. Over two-thirds of the group (69%) with removal of PFT had a profile of typically mild dysarthria. Prominent speech deficits included consonant imprecision, reduced rate, monopitch and monoloudness. We conclude that speech deficits may persist even up to 10 years post-surgery in participants who have not shown mutism in the acute phase. Of cases with unilateral lesions, poorer outcomes were associated with right cerebellar tumours compared to left, consistent with the notion based on adult data that speech is controlled by reciprocal right cerebellar/left frontal interactions. These results confirm the important role of the cerebellum in the control of fine speech movements in children.

  4. Controlateral cavernous syndrome, brainstem congestion and posterior fossa venous thrombosis with cerebellar hematoma related to a ruptured intracavernous carotid artery aneurysm.

    PubMed

    Aldea, Sorin; Guedin, Pierre; Roccatagliata, Luca; Boulin, Anne; Auliac, Stéphanie; Dupuy, Michel; Cerf, Charles; Gaillard, Stéphan; Rodesch, Georges

    2011-06-01

    Intracavernous carotid artery aneurysms (ICCAs) are rarely associated with life-threatening complications. We describe a 55-year-old woman who, after the rupture of an intracavernous carotid artery aneurysm, presented with a contralateral cavernous sinus syndrome and severe posterior fossa and spinal cord symptoms. Following parent artery occlusion, thrombosis of the posterior fossa and spinal cord veins caused a progressive worsening of the neurological status to a "locked-in" state. The patient fully recovered with anticoagulation therapy. Comprehension of the pathophysiological mechanism associated with the rupture of ICCA and early diagnosis of the related symptoms are essential in order to plan a correct treatment that includes the management of the aneurysm rupture and of possible complications related to venous thrombosis.

  5. Two alternative dural sealing techniques in posterior fossa surgery: (Polylactide-co-glycolide) self-adhesive resorbable membrane versus polyethylene glycol hydrogel

    PubMed Central

    Schiariti, Marco; Acerbi, Francesco; Broggi, Morgan; Tringali, Giovanni; Raggi, Alberto; Broggi, Giovanni; Ferroli, Paolo

    2014-01-01

    Background: Post-operative cerebrospinal fluid (CSF) leak in posterior fossa surgery remains a significant source of morbidity. TissuePatchDural (TPD), a novel impermeable adhesive membrane, was used to reinforce dural closure. A comparison with one of the most commonly used dural sealing devices, DuraSeal, has been made. Methods: A retrospective, single-center study was conducted on 161 patients who underwent elective posterior fossa surgery. On surgeon's opinion, when a primary watertight closure was not possible, they received TPD or DuraSeal to reinforce dural closure. Results: Out of 161 patients analyzed, 115 were treated with TPD and 46 with DuraSeal. The post-operative leaks related purely to TPD or DuraSeal failure were recognized in 3 (2.6%) and 5 (10.86%) cases, respectively (P = 0.015). The presence of pre- and post-operative risk factors was associated with an increased incidence of CSF leak in both groups. TPD showed a better control in patients without these risk factors (P = 0.08). The incidence of CSF leak in patients who underwent posterior fossa surgery by craniectomy was statistically lower in TPD group compared to DuraSeal group (3.22% vs 17.8%, respectively; P = 0.008) Conclusions: TPD seems to be a safe tool for use as an adjunct to standard dural closure in posterior fossa surgery, particularly in patients without pre- or post-oper ative risk factors, in those who did not develop hydrocephalus, and who underwent craniectomy. The CSF leak rate in TPD group was found to be lower or within the range of the more advanced alternative dural closure strategies, including polyethylene glycol (PEG)-based sealant. PMID:25593755

  6. Delayed cerebrospinal fluid leak after watertight dural closure with a polyethylene glycol hydrogel dural sealant in posterior fossa surgery: case report.

    PubMed

    Jito, Junya; Nitta, Naoki; Nozaki, Kazuhiko

    2014-01-01

    A polyethylene glycol (PEG) hydrogel sealant recently has been approved as an adjunct to sutured dural closure in Japan. We treated consecutive six patients with PEG hydrogel sealant in posterior fossa operation. Three of six cases suffered delayed cerebrospinal fluid (CSF) leak after watertight dural closure with the PEG hydrogel sealant, although there was no leak case which was treated with fibrin glue, before 2 years until the adoption of the new material. These patients underwent posterior fossa craniotomy and discharged without remarkable CSF leak. The pseudomeningocele under the occipital wound caused the CSF leak occurr from 5th to 7th week postoperatively. All CSF leak cases needed surgical repair. At the repair, the PEG hydrogel was liquefied and almost absorbed. A fistula on the closure line and a dead space after the absorption of the PEG hydrogel was observed. When the absorbable PEG hydrogel sealant plugs in small gaps of sutured dura, its properties to prevent adhesion might suppress healing process of dural closure, so that CSF could leak through the gaps and collect as a pseudomeningocele in the dead space after absorption of the PEG hydrogel. In posterior fossa surgery a PEG hydrogel sealant should be applied when dural edges are closed tightly without any gaps.

  7. DTI fiber tractography of cerebro-cerebellar pathways and clinical evaluation of ataxia in childhood posterior fossa tumor survivors.

    PubMed

    Oh, Myung Eun; Driever, Pablo Hernáiz; Khajuria, Rajiv K; Rueckriegel, Stefan Mark; Koustenis, Elisabeth; Bruhn, Harald; Thomale, Ulrich-Wilhelm

    2017-01-01

    Pediatric posterior fossa (PF) tumor survivors experience long-term motor deficits. Specific cerebrocerebellar connections may be involved in incidence and severity of motor dysfunction. We examined the relationship between long-term ataxia as well as fine motor function and alteration of differential cerebellar efferent and afferent pathways using diffusion tensor imaging (DTI) and tractography. DTI-based tractography was performed in 19 patients (10 pilocytic astrocytoma (PA) and 9 medulloblastoma patients (MB)) and 20 healthy peers. Efferent Cerebello-Thalamo-Cerebral (CTC) and afferent Cerebro-Ponto-Cerebellar (CPC) tracts were reconstructed and analyzed concerning fractional anisotropy (FA) and volumetric measurements. Clinical outcome was assessed with the International Cooperative Ataxia Rating Scale (ICARS). Kinematic parameters of fine motor function (speed, automation, variability, and pressure) were obtained by employing a digitizing graphic tablet. ICARS scores were significantly higher in MB patients than in PA patients. Poorer ICARS scores and impaired fine motor function correlated significantly with volume loss of CTC pathway in MB patients, but not in PA patients. Patients with pediatric post-operative cerebellar mutism syndrome showed higher loss of CTC pathway volume and were more atactic. CPC pathway volume was significantly reduced in PA patients, but not in MB patients. Neither relationship was observed between the CPC pathway and ICARS or fine motor function. There was no group difference of FA values between the patients and healthy peers. Reduced CTC pathway volumes in our cohorts were associated with severity of long-term ataxia and impaired fine motor function in survivors of MBs. We suggest that the CTC pathway seems to play a role in extent of ataxia and fine motor dysfunction after childhood cerebellar tumor treatment. DTI may be a useful tool to identify relevant structures of the CTC pathway and possibly avoid surgically induced long

  8. Clinical and methodological confounders in assessing the cerebellar cognitive affective syndrome in adult patients with posterior fossa tumours.

    PubMed

    Omar, Dashne; Ryan, Tracy; Carson, Alan; Bak, Thomas H; Torrens, Lorna; Whittle, Ian

    2014-12-01

    The cerebellar cognitive affective syndrome (CCAS) was first described by Schmahmann and Sherman as a constellation of symptoms including dysexecutive syndrome, spatial cognitive deficit, linguistic deficits and behavioural abnormalities in patients with a lesion in the cerebellum with otherwise normal brain. Neurosurgical patients with cerebellar tumours constitute one of the cohorts in which the CCAS has been described. In this paper, we present a critical review of the literature of this syndrome in neurosurgical patients. Thereafter, we present a prospective clinical study of 10 patients who underwent posterior fossa tumour resection and had a detailed post-operative neuropsychological, neuropsychiatric and neuroradiological assessment. Because our findings revealed a large number of perioperative neuroradiological confounding variables, we reviewed the neuroimaging of a further 20 patients to determine their prevalence. Our literature review revealed that study design, methodological quality and sometimes both diagnostic criteria and findings were inconsistent. The neuroimaging study (pre-operative, n = 10; post-operative, n = 10) showed very frequent neuroradiological confounding complications (e.g. hydrocephalus; brainstem compression; supratentorial lesions and post-operative subdural hygroma); the impact of such features had largely been ignored in the literature. Findings from our clinical study showed various degree of deficits in neuropsychological testing (n = 1, memory; n = 3, verbal fluency; n = 3, attention; n = 2, spatial cognition deficits; and n = 1, behavioural changes), but no patient had full-blown features of CCAS. Our study, although limited, finds no robust evidence of the CCAS following surgery. This and our literature review highlight a need for guidelines regarding study design and methodology when attempting to evaluate neurosurgical cases with regard to the potential CCAS.

  9. MR-Based Morphometry of the Posterior Fossa in Fetuses with Neural Tube Defects of the Spine

    PubMed Central

    Woitek, Ramona; Dvorak, Anton; Weber, Michael; Seidl, Rainer; Bettelheim, Dieter; Schöpf, Veronika; Amann, Gabriele; Brugger, Peter C.; Furtner, Julia; Asenbaum, Ulrika; Prayer, Daniela; Kasprian, Gregor

    2014-01-01

    Objectives In cases of “spina bifida,” a detailed prenatal imaging assessment of the exact morphology of neural tube defects (NTD) is often limited. Due to the diverse clinical prognosis and prenatal treatment options, imaging parameters that support the prenatal differentiation between open and closed neural tube defects (ONTDs and CNTDs) are required. This fetal MR study aims to evaluate the clivus-supraocciput angle (CSA) and the maximum transverse diameter of the posterior fossa (TDPF) as morphometric parameters to aid in the reliable diagnosis of either ONTDs or CNTDs. Methods The TDPF and the CSA of 238 fetuses (20–37 GW, mean: 28.36 GW) with a normal central nervous system, 44 with ONTDS, and 13 with CNTDs (18–37 GW, mean: 24.3 GW) were retrospectively measured using T2-weighted 1.5 Tesla MR -sequences. Results Normal fetuses showed a significant increase in the TDPF (r = .956; p<.001) and CSA (r = .714; p<.001) with gestational age. In ONTDs the CSA was significantly smaller (p<.001) than in normal controls and CNTDs, whereas in CNTDs the CSA was not significantly smaller than in controls (p = .160). In both ONTDs and in CNTDs the TDPF was significantly different from controls (p<.001). Conclusions The skull base morphology in fetuses with ONTDs differs significantly from cases with CNTDs and normal controls. This is the first study to show that the CSA changes during gestation and that it is a reliable imaging biomarker to distinguish between ONTDs and CNTDs, independent of the morphology of the spinal defect. PMID:25393279

  10. Posterior fossa tumor

    MedlinePlus

    ... and the tumor can easily press on delicate structures if it grows. Depending on the type and size of the tumor, radiation treatment may also be used after surgery. Support Groups You can ease the stress of illness ...

  11. Comparison of posterior fossa decompression with and without duraplasty for the surgical treatment of Chiari malformation type I in adult patients

    PubMed Central

    Chen, Junchen; Li, Yongning; Wang, Tianyu; Gao, Jun; Xu, Jincheng; Lai, Runlong; Tan, Dianhui

    2017-01-01

    Abstract Chiari malformation type I (CM-I) is a congenital neurosurgical disease about the herniation of cerebellar tonsil through the foramen magnum. A variety of surgical techniques for CM-I have been used, and there is a controversy whether to use posterior fossa decompression with duraplasty (PFDD) or posterior fossa decompression without duraplasty (PFD) in CM-I patients. Here, we compared the clinical results and effectiveness of PFDD and PFD in adult patients with CM-I. The cases of 103 adult CM-I patients who underwent posterior fossa decompression with or without duraplasty from 2008 to 2014 were reviewed retrospectively. Patients were divided into 2 groups according to the surgical techniques: PFDD group (n = 70) and PFD group (n = 33). We compared the demographics, preoperative symptoms, radiographic characteristics, postoperative complications, and clinical outcomes between the PFD and PFDD patients. No statistically significant differences were found between the PFDD and PFD groups with regard to demographics, preoperative symptoms, radiographic characteristics, and clinical outcomes(P > 0.05); however, the postoperative complication aseptic meningitis occurred more frequently in the PFDD group than in the PFD group (P = 0.027). We also performed a literature review about the PFDD and PFD and made a summary of these preview studies. Our study suggests that both PFDD and PFD could achieve similar clinical outcomes for adult CM-I patients. The choice of surgical procedure should be based on the patient's condition. PFDD may lead to a higher complication rate and autologous grafts seemed to perform better than nonautologous grafts for duraplasty. PMID:28121938

  12. Computational Investigation of Cerebrospinal Fluid Dynamics in the Posterior Cranial Fossa and Cervical Subarachnoid Space in Patients with Chiari I Malformation

    PubMed Central

    Støverud, Karen-Helene; Langtangen, Hans Petter; Ringstad, Geir Andre; Eide, Per Kristian; Mardal, Kent-Andre

    2016-01-01

    Purpose Previous computational fluid dynamics (CFD) studies have demonstrated that the Chiari malformation is associated with abnormal cerebrospinal fluid (CSF) flow in the cervical part of the subarachnoid space (SAS), but the flow in the SAS of the posterior cranial fossa has received little attention. This study extends previous modelling efforts by including the cerebellomedullary cistern, pontine cistern, and 4th ventricle in addition to the cervical subarachnoid space. Methods The study included one healthy control, Con1, and two patients with Chiari I malformation, P1 and P2. Meshes were constructed by segmenting images obtained from T2-weighted turbo spin-echo sequences. CFD simulations were performed with a previously verified and validated code. Patient-specific flow conditions in the aqueduct and the cervical SAS were used. Two patients with the Chiari malformation and one control were modelled. Results The results demonstrated increased maximal flow velocities in the Chiari patients, ranging from factor 5 in P1 to 14.8 in P2, when compared to Con1 at the level of Foramen Magnum (FM). Maximal velocities in the cervical SAS varied by a factor 2.3, while the maximal flow in the aqueduct varied by a factor 3.5. The pressure drop from the pontine cistern to the cervical SAS was similar in Con1 and P1, but a factor two higher in P2. The pressure drop between the aqueduct and the cervical SAS varied by a factor 9.4 where P1 was the one with the lowest pressure jump and P2 and Con1 differed only by a factor 1.6. Conclusion This pilot study demonstrates that including the posterior cranial fossa is feasible and suggests that previously found flow differences between Chiari I patients and healthy individuals in the cervical SAS may be present also in the SAS of the posterior cranial fossa. PMID:27727298

  13. Texture analysis of T1- and T2-weighted MR images and use of probabilistic neural network to discriminate posterior fossa tumours in children

    PubMed Central

    Orphanidou-Vlachou, Eleni; Vlachos, Nikolaos; Davies, Nigel P; Arvanitis, Theodoros N; Grundy, Richard G; Peet, Andrew C

    2014-01-01

    Brain tumours are the most common solid tumours in children, representing 20% of all cancers. The most frequent posterior fossa tumours are medulloblastomas, pilocytic astrocytomas and ependymomas. Texture analysis (TA) of MR images can be used to support the diagnosis of these tumours by providing additional quantitative information. MaZda software was used to perform TA on T1- and T2-weighted images of children with pilocytic astrocytomas, medulloblastomas and ependymomas of the posterior fossa, who had MRI at Birmingham Children's Hospital prior to treatment. The region of interest was selected on three slices per patient in Image J, using thresholding and manual outlining. TA produced 279 features, which were reduced using principal component analysis (PCA). The principal components (PCs) explaining 95% of the variance were used in a linear discriminant analysis (LDA) and a probabilistic neural network (PNN) to classify the cases, using DTREG statistics software. PCA of texture features from both T1- and T2-weighted images yielded 13 PCs to explain >95% of the variance. The PNN classifier for T1-weighted images achieved 100% accuracy on training the data and 90% on leave-one-out cross-validation (LOOCV); for T2-weighted images, the accuracy was 100% on training the data and 93.3% on LOOCV. A PNN classifier with T1 and T2 PCs achieved 100% accuracy on training the data and 85.8% on LOOCV. LDA classification accuracies were noticeably poorer. The features found to hold the highest discriminating potential were all co-occurrence matrix derived, where adjacent pixels had highly correlated intensities. This study shows that TA can be performed on standard T1- and T2-weighted images of childhood posterior fossa tumours using readily available software to provide high diagnostic accuracy. Discriminatory features do not correspond to those used in the clinical interpretation of the images and therefore provide novel tumour information. Copyright © 2014 John Wiley

  14. Lumbar subdural cerebrospinal fluid collection with acute cauda equina syndrome after posterior fossa decompression for Chiari malformation Type I: case report.

    PubMed

    Darwish, Houssein A; Oldfield, Edward H

    2016-09-01

    This report describes the circumstances of a patient with a cauda equina syndrome due to the development of a lumbar subdural CSF collection with ventral displacement of the cauda equina shortly following posterior fossa decompression for Chiari malformation Type I (CM-I). This unusual, but clinically significant, complication was successfully treated with percutaneous drainage of the extraarachnoid CSF collection. Although there are a few cases of intracranial subdural hygroma developing after surgery for CM-I, often attributed to a pinhole opening in the arachnoid, as far as the authors can determine, a spinal subdural hygroma associated with surgery for CM-I has not been recognized.

  15. Differences in Supratentorial Damage of White Matter in Pediatric Survivors of Posterior Fossa Tumors With and Without Adjuvant Treatment as Detected by Magnetic Resonance Diffusion Tensor Imaging

    SciTech Connect

    Rueckriegel, Stefan Mark; Driever, Pablo Hernaiz; Blankenburg, Friederike; Luedemann, Lutz; Henze, Guenter; Bruhn, Harald

    2010-03-01

    Purpose: To elucidate morphologic correlates of brain dysfunction in pediatric survivors of posterior fossa tumors by using magnetic resonance diffusion tensor imaging (DTI) to examine neuroaxonal integrity in white matter. Patients and Methods: Seventeen medulloblastoma (MB) patients who had received surgery and adjuvant treatment, 13 pilocytic astrocytoma (PA) patients who had been treated only with surgery, and age-matched healthy control subjects underwent magnetic resonance imaging on a 3-Tesla system. High-resolution conventional T1- and T2-weighted magnetic resonance imaging and DTI data sets were obtained. Fractional anisotropy (FA) maps were analyzed using tract-based spatial statistics, a part of the Functional MRI of the Brain Software Library. Results: Compared with control subjects, FA values of MB patients were significantly decreased in the cerebellar midline structures, in the frontal lobes, and in the callosal body. Fractional anisotropy values of the PA patients were not only decreased in cerebellar hemispheric structures as expected, but also in supratentorial parts of the brain, with a distribution similar to that in MB patients. However, the amount of significantly decreased FA was greater in MB than in PA patients, underscoring the aggravating neurotoxic effect of the adjuvant treatment. Conclusions: Neurotoxic mechanisms that are present in PA patients (e.g., internal hydrocephalus and damaged cerebellar structures affecting neuronal circuits) contribute significantly to the alteration of supratentorial white matter in pediatric posterior fossa tumor patients.

  16. Preservation of the Myofascial Cuff During Posterior Fossa Surgery to Reduce the Rate of Pseudomeningocele Formation and Cerebrospinal Fluid Leak: A Technical Note

    PubMed Central

    Felbaum, Daniel R; Anaizi, Amjad; Mason, Robert B; Jean, Walter C; Voyadzis, Jean M

    2016-01-01

    Introduction: Suboccipital craniotomy is a workhorse neurosurgical operation for approaching the posterior fossa but carries a high risk of pseudomeningocele and cerebrospinal fluid (CSF) leak. We describe our experience with a simple T-shaped fascial opening that preserves the occipital myofascial cuff as compared to traditional methods to reduce this risk. Methods: A single institution, retrospective review of prospectively collected database was performed of patients that underwent a suboccipital craniectomy or craniotomy. Patient data was reviewed for craniotomy or craniectomy, dural graft, and/or sealant use as well as CSF complications. A pseudomeningocele was defined as a subcutaneous collection of cerebrospinal fluid palpable clinically and confirmed on imaging. A CSF leak was defined as a CSF-cutaneous fistula manifested by CSF leaking through the wound. All patients underwent regular postoperative visits of two weeks, one month, and three months. Results: Our retrospective review identified 33 patients matching the inclusion criteria. Overall, our cohort had a 21% (7/33) rate of clinical and radiographic pseudomeningocele formation with 9% (3/33) requiring surgical revision or a separate procedure. The rate of clinical and radiographic pseudomeningocele formation in the myofascial cuff preservation technique was less than standard techniques (12% and 31%, respectively). Revision or further surgical procedures were also reduced in the myofascial cuff preservation technique vs. the standard technique (6% vs 13%). Conclusions: Preservation of the myofascial cuff during posterior fossa surgery is a simple and adoptable technique that reduces the rate of pseudomeningocele formation and CSF leak as compared with standard techniques.   PMID:28133584

  17. Clinical significance of changes in pB-C2 distance in Chiari I malformation patients following posterior fossa decompression: a single-institution experience

    PubMed Central

    Maurer, Adrian J.; Duong, Ngoc Quyen; Bonney, Phillip A.; Cheema, Ahmed A.; Glenn, Chad A.; Safavi-Abbasi, Sam; Stoner, Julie B.; Mapstone, Timothy B.

    2016-01-01

    Object The coexistence of Chiari I malformations and ventral brainstem compression (VBSC) has been well-documented, but the change in VBSC after posterior fossa decompression (PFD) has had little investigation. In this study we evaluate the incidence and degree of VBSC in patients with Chiari I malformations and determine the change in VBSC after PFD, correlating changes in VBSC with clinical status and the need for further intervention. Methods Patients who underwent PFD for Chiari I malformations by the senior author from November 2005 – January 2013 with complete radiographic records were included in the analysis. The following data were obtained: subjective and objective measures of ventral brainstem compression; relationship of odontoid to Chamberlain’s, McGregor’s, McRae’s, and Wackenheim’s lines; clival length; foramen magnum diameter; and basal angle. The objective evaluation of VBSC was performed with the senior author’s previously described method using pB-C2 distance. Statistical analyses were performed using paired t-tests and a mixed effects ANOVA model. Results Thirty-one patients were included in the analysis. The mean age of the cohort was 10.0 years. There was a small but statistically significant increase in pB-C2 postoperatively (0.5 mm, p < 0.0001 via mixed effects ANOVA). Eleven patients had postoperative pB-C2 values greater than 9 mm. The mean distance from the odontoid tip to Wackenheim’s line did not change after PFD, signifying postoperative occipitocervical stability. No patients underwent transoral odontoidectomy or occipitocervical fusion. No patients experienced clinical deterioration after PFD. Conclusions The increase in pB-C2 in patients undergoing posterior fossa decompression is likely a result of releasing the posterior vector on the ventral dura, allowing it to relax posteriorly. This increase is well-tolerated, and a postoperative pB-C2 measurement of greater than 9 mm in light of stable craniocervical metrics and

  18. Posterior fossa decompression combined with resection of the cerebellomedullary fissure membrane and expansile duraplasty: a radical and rational surgical treatment for Arnold-Chiari type I malformation.

    PubMed

    Liang, Chen Jian; Dong, Qiu Jian; Xing, You Heng; Shan, Ma; Wen, Lian Xiao; Qiang, Zhong Yuan; Ping, Zhang Qing; Tao, Peng Zhi; Ping, Huang Xiao

    2014-12-01

    This study aims to introduce a new surgical procedure for the treatment of Arnold-Chiari type I malformation (ACM-1) and to compare its effectiveness with the techniques described in previous studies. We performed the following procedures: foramen magnum decompression combined with the removal of both the atlanto-occipital membrane, extended resection of the cerebellomedullary fissure arachnoid membrane, and artificial duraplasty to enlarge the membranic posterior fossa without resecting the cerebellar tonsils and syringosubarachnoid shunting. There were 21 ACM-1 patients: 12 cases had osteo-compression on the cerebellar hemisphere, 18 cases had thickened adhered fabric ring that stretched from arachnoid membrane to cerebellar hemisphere, and 15 cases with syringomyelia. The patients were followed up for 6 months to 3 years after the surgery. All patients showed a remarkable recovery of syringomyelia. There were no morbidity or death related to the surgery. Most of ACM-1 patients, the osteo- and membrane compression on cerebellar hemisphere and tonsil were observed during the operation. Therefore, decompression of foramen magnum and posterior craniocervical combined with the removal of cerebellomedullary fissure arachnoid membrane and placement of an artificial dural graft should be considered as a comprehensive option of minimally invasive surgery and rational and radical treatment of ACM-1. Our experience showed that, by using our procedure, shunting becomes no longer necessary in the treatment of ACM-1-associated syringomyelia.

  19. Clinical significance of changes in pB-C2 distance in patients with Chiari Type I malformations following posterior fossa decompression: a single-institution experience.

    PubMed

    Bonney, Phillip A; Maurer, Adrian J; Cheema, Ahmed A; Duong, Quyen; Glenn, Chad A; Safavi-Abbasi, Sam; Stoner, Julie A; Mapstone, Timothy B

    2016-03-01

    OBJECT The coexistence of Chiari malformation Type I (CM-I) and ventral brainstem compression (VBSC) has been well documented, but the change in VBSC after posterior fossa decompression (PFD) has undergone little investigation. In this study the authors evaluated VBSC in patients with CM-I and determined the change in VBSC after PFD, correlating changes in VBSC with clinical status and the need for further intervention. METHODS Patients who underwent PFD for CM-I by the senior author from November 2005 to January 2013 with complete radiological records were included in the analysis. The following data were obtained: objective measure of VBSC (pB-C2 distance); relationship of odontoid to Chamberlain's, McGregor's, McRae's, and Wackenheim's lines; clival length; foramen magnum diameter; and basal angle. Statistical analyses were performed using paired t-tests and a mixed-effects ANOVA model. RESULTS Thirty-one patients were included in the analysis. The mean age of the cohort was 10.0 years. There was a small but statistically significant increase in pB-C2 postoperatively (0.5 mm, p < 0.0001, mixed-effects ANOVA). Eleven patients had postoperative pB-C2 values greater than 9 mm. The mean distance from the odontoid tip to Wackenheim's line did not change after PFD, signifying postoperative occipitocervical stability. No patients underwent transoral odontoidectomy or occipitocervical fusion. No patients experienced clinical deterioration after PFD. CONCLUSIONS The increase in pB-C2 in patients undergoing PFD may occur as a result of releasing the posterior vector on the ventral dura, allowing it to relax posteriorly. This increase appears to be well-tolerated, and a postoperative pB-C2 measurement of more than 9 mm in light of stable craniocervical metrics and a nonworsened clinical examination does not warrant further intervention.

  20. Posterior fossa decompression with and without duraplasty for the treatment of Chiari malformation type I-a systematic review and meta-analysis.

    PubMed

    Xu, Hao; Chu, LinYang; He, Rui; Ge, Chang; Lei, Ting

    2017-04-01

    The treatment of Chiari malformation type 1 (CM-I) with posterior fossa decompression without (PFD) or with duraplasty (PFDD) is controversial. Our aim is to compare the clinical outcome between the two methods for the treatment of CM-I. In this paper, the authors report a systematic review and meta-analysis of operation time, clinical improvement, and complications of PFD compared with PFDD for the treatment of CM-I. Randomized or non-randomized controlled trials of PFD and PFDD were considered for inclusion. Twelve published reports of eligible studies involving 841participants meet the inclusion criteria. There is significant difference in the operative time [mean difference = -74.63, 95 % CI (-83.02, -66.25), p < 0.05] in favor of PFD compared with PFDD. There is significant difference in overall complication rates [mean difference = 0.34, 95 % CI (0.19, 0.60), p < 0.05] and rates of CSF leak [mean difference = 0.24, 95 % CI (0.07, 0.78), p < 0.05] in favor of PFD groups. However, there is significant difference in the clinical improvement rate in favor of the PFDD group [mean difference = 0.85, 95 % CI (0.73, 0.99), p < 0.05]. Although PFDD is related with longer operation time and higher CSF leak rate, it can still be considered as a preferable treatment option for most CM-I patients for its higher improvement rate. More evidence from advanced multi-center studies are needed to provide illumination for the surgical decision making of CM-I.

  1. Medusae Fossae

    NASA Technical Reports Server (NTRS)

    2002-01-01

    [figure removed for brevity, see original site] (Released 31 July 2002) This image crosses the equator at about 155 W longitude and shows a sample of the middle member of the Medusae Fossae formation. The layers exposed in the southeast-facing scarp suggest that there is a fairly competent unit underlying the mesa in the center of the image. Dust-avalanches are apparent in the crater depression near the middle of the image. The mesa of Medusae Fossae material has the geomorphic signatures that are typical of the formation elsewhere on Mars, but the surface is probably heavily mantled with fine dust, masking the small-scale character of the unit. The close proximity of the Medusae Fossae unit to the Tharsis region may suggest that it is an ignimbrite or volcanic airfall deposit, but it's eroded character hasn't preserved the primary depositional features that would give away the secrets of formation. One of the most interesting feature in the image is the high-standing knob at the base of the scarp in the lower portion of the image. This knob or butte is high standing because it is composed of material that is not as easily eroded as the rest of the unit. There are a number of possible explanations for this feature, including volcano, inverted crater, or some localized process that caused once friable material to become cemented. Another interesting set of features are the long troughs on the slope in the lower portion of the image. The fact that the features keep the same width for the entire length suggests that these are not simple landslides.

  2. Claritas Fossae

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 20 June 2002) The Science The eastern rim of this unnamed crater in Claritas Fossae is very degraded. This indicates that this crater is very ancient and has been subjected to erosion and subsequent bombardment from other impactors such as asteroids and comets. One of these later (younger) craters is seen in the upper right of this image superimposed upon the older crater rim material. Note that this smaller younger crater rim is sharper and more intact than the older crater rim. This region is also mantled with a blanket of dust. This dust mantle causes the underlying topography to take on a more subdued appearance. The Story Not every crater on Mars has a name. The one in this image doesn't. What would you name it if you could? That's what planetary scientists ask themselves when they come across such features. If they think of a good name, they can submit it for approval to a group of world astronomers who are members of the International Astronomical Union. There are special rules, though, so not any name can be selected. The selection committee especially wants to make sure that all world cultures are represented. While this crater may not have a name, the region it lies in does. It is called Claritas Fossae. 'Claritas' is the Latin word for 'bright.' 'Fossae' are long, narrow, shallow depressions that mark the region. You can see these best in the context image to the right. You can tell just by looking at this crater that it is very ancient. Its rim is very degraded from erosion and bombardment from other impactors such as asteroids and comets. Compare its roughened rim to the smoother outline of the small crater on the rim's edge (upper right). The smoother rim of the small one means that it is considerably younger than its older, choppier neighbor. You know it was certainly created after the large crater because it lies on top of the rim. Other than the old and young generations of craters, the surface looks pretty uniform in hue and perhaps even

  3. Mangala Fossa

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 29 May 2002) The Science Today's THEMIS release captures Mangala Fossa. Mangala Fossa is a graben, which in geologic terminology translates into a long parallel to semi-parallel fracture or trough. Grabens are dropped or downthrown areas relative to the rocks on either side and these features are generally longer than they are wider. There are numerous dust devil trails seen in this image. In the lower portion of this image several dust devil tracks can be seen cutting across the upper surface then down the short stubby channel and finally back up and over to the adjacent upper surface. Some dust avalanche streaks on slopes are also visible. The rough material in the upper third of the image contains a portion of the rim of a 90 km diameter crater located in Daedalia Planum. The smooth crater floor has a graben (up to 7 km wide) and channel (2 km wide) incised into its surface. In the middle third and right of this image one can see ripples (possibly fossil dunes) on the crater floor material just above the graben. The floor of Mangala Fossa and the southern crater floor surface also have smaller linear ridges trending from the upper left to lower right. These linear ridges could be either erosional (yardangs) or depositional (dunes) landforms. The lower third of the scene contains a short stubby channel (near the right margin) and lava flow front (lower left). The floor of this channel is fairly smooth with some linear crevasses located along its course. One gets the impression that the channel floor is mantled with some type of indurated material that permits cracks to form in its surface. The Story In the Daedalia Plains on Mars, the rim of an old eroded crater rises up, a wreck of its former self (see context image at right). From the rough, choppy crater rim (top of the larger THEMIS image), the terrain descends to the almost smooth crater floor, gouged deeply by a trough, a channel, and the occasional dents of small, scattered craters. The deep

  4. Pituitary fossa: a correlative anatomic and MR study

    SciTech Connect

    Mark, L.; Pech, P.; Daniels, D.; Charles, C.; Williams, A.; Haughton, V.

    1984-11-01

    This study characterizes the normal appearance of the pituitary fossa in partial saturation magnetic resonance (MR) images. In sagittal images, the pituitary fossa appears inhomogeneous. Correlation of sagittal MR images in normal subjects with sagittal cryomicrotomic images in cadavers suggests that the highest intensity signal from the posterior-inferior pituitary fossa is due to a fat pad. This conclusion was supported by MR images and postmortem cryotome sections obtained in normal subhuman primates.

  5. Tantalus Fossae

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 25 June 2002) The Science Tantalus Fossae is a set of long valleys on the eastern side of Alba Patera. These valleys are referred to as grabens and are formed by extension of the crust and faulting. When large amounts of pressure or tension are applied to rocks on timescales that are fast enough that the rock cannot respond by deforming, the rock breaks along faults. In the case of a graben, two parallel faults are formed by extension of the crust and the rock in between the faults drops downward into the space created by the extension. Numerous sets of grabens are visible in this THEMIS image, trending from north-northeast to south-southwest. Because the faults defining the graben are formed parallel to the direction of the applied stress, we know that extensional forces were pulling the crust apart in the west-northwest/east-southeast direction. The large number of grabens around Alba Patera is generally believed to be the result of extensional forces associated with the uplift of Alba Patera. Also visible in this image are a series of linearly aligned pits, called a pit chain. The pits are not the result of impact cratering, but are similar to sinkholes on Earth. Sinkholes are typically formed by the removal of rock (commonly limestone) underground by groundwater -- when enough rock is removed, the overlying rock becomes too heavy to be supported, and it collapses, forming a pit. Unlike sinkholes, however, the pit chains near Alba Patera were likely formed when empty underground lava tubes collapsed, accounting for the presence and alignment of many pits. Numerous channel features are also observed in the image, and follow the local topographic slope, which is downhill to the east-southeast. One of these, a long channel in the center of the image, nicely demonstrates the complex relations possible between geologic features. The geologist's rule of superposition says that a feature on top of (superposing) another feature, or cutting across another

  6. Tantalus Fossae

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 25 June 2002) The Science Tantalus Fossae is a set of long valleys on the eastern side of Alba Patera. These valleys are referred to as grabens and are formed by extension of the crust and faulting. When large amounts of pressure or tension are applied to rocks on timescales that are fast enough that the rock cannot respond by deforming, the rock breaks along faults. In the case of a graben, two parallel faults are formed by extension of the crust and the rock in between the faults drops downward into the space created by the extension. Numerous sets of grabens are visible in this THEMIS image, trending from north-northeast to south-southwest. Because the faults defining the graben are formed parallel to the direction of the applied stress, we know that extensional forces were pulling the crust apart in the west-northwest/east-southeast direction. The large number of grabens around Alba Patera is generally believed to be the result of extensional forces associated with the uplift of Alba Patera. Also visible in this image are a series of linearly aligned pits, called a pit chain. The pits are not the result of impact cratering, but are similar to sinkholes on Earth. Sinkholes are typically formed by the removal of rock (commonly limestone) underground by groundwater -- when enough rock is removed, the overlying rock becomes too heavy to be supported, and it collapses, forming a pit. Unlike sinkholes, however, the pit chains near Alba Patera were likely formed when empty underground lava tubes collapsed, accounting for the presence and alignment of many pits. Numerous channel features are also observed in the image, and follow the local topographic slope, which is downhill to the east-southeast. One of these, a long channel in the center of the image, nicely demonstrates the complex relations possible between geologic features. The geologist's rule of superposition says that a feature on top of (superposing) another feature, or cutting across another

  7. Medusae Fossae #1

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Extensive wind-swept plains of the Medusae Fossae formation on Mars. This northern subframe image, frame 3104, is of a 3.0 x 4.7 km area centered near 2.4 degrees north, 163.8 degrees west.

    Figure caption from Science Magazine

  8. Medusae Fossae #2

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Extensive wind-swept plains of the Medusae Fossae formation on Mars. This southern subframe image, frame 3104, is of a 3.0 x 4.7 km area centered near 2.0 degrees north, 163.8 degrees west.

    Figure caption from Science Magazine

  9. Yardangs in Medusa Fossae

    NASA Technical Reports Server (NTRS)

    2002-01-01

    [figure removed for brevity, see original site] (Released 29 July 2002) This THEMIS visible image covers a portion of the Medusa Fossae formation, near the equator of Mars. The most characteristic feature of the Medusa Fossae formation is the abundance of 'yardangs', which are erosional landforms carved by the wind. These features usually form in a linear fashion, and can be indicators of prevailing paleowind directions. On Earth, yardangs are typically found in rocks that are easily eroded, such as those that form from consolidated volcanic ash, dust-fall deposits or lake sediments. In this particular area of Medusa Fossae, the size, spacing, and orientation of the yardangs varies throughout the image. The largest form a stripe across the center of the image, while the smallest are found in the top half of the image (look closely). The small yardangs at the very top of the image are oriented NW-SE; however, the orientation changes to NE-SW near the bright ridge in the center of the image. The variation in size and orientation appears to correspond with topographic layers, and may be due either to differences in consolidation or changes in wind strength or direction as the yardangs were formed. Finally, the terrain in the lower third of the image appears etched or pitted, and was probably also formed by wind erosion.

  10. Pterygopalatine Fossa: Not a Mystery!

    PubMed

    Derinkuyu, Betul Emine; Boyunaga, Oznur; Oztunali, Cigdem; Alimli, Ayse Gul; Ucar, Murat

    2016-12-06

    The pterygopalatine fossa is an important anatomic crossroads that is connected with numerous intra- and extracranial spaces via foramina and fissures. Although this fossa is small, its central location in the skull base and its communications provide clinical, radiological, and anatomical significance. In this pictorial review, we aimed to describe the radiologic anatomy of the pterygopalatine fossa, as well as to give some pathologic examples to better understand this major conduit.

  11. Brainstem variant of posterior reversible encephalopathy syndrome: A case report

    PubMed Central

    Caranci, Ferdinando; Belfiore, Maria Paola; Manzi, Francesca; Pagliano, Pasquale; Cirillo, Sossio

    2015-01-01

    Posterior reversible encephalopathy syndrome (PRES) is a clinico-radiological condition, generally observed in conjunction with severe and acute hypertension, that involves mainly the posterior head areas (occipital and temporal lobes) and anterior “watershed” areas. In this syndrome it is rare to observe a predominant involvement of the brainstem. We describe the clinical and radiological findings in a patient with brainstem involvement, discussing its pathophysiological features and possible differential diagnosis. PMID:26515750

  12. Brainstem variant of posterior reversible encephalopathy syndrome: A case report.

    PubMed

    Tortora, Fabio; Caranci, Ferdinando; Belfiore, Maria Paola; Manzi, Francesca; Pagliano, Pasquale; Cirillo, Sossio

    2015-12-01

    Posterior reversible encephalopathy syndrome (PRES) is a clinico-radiological condition, generally observed in conjunction with severe and acute hypertension, that involves mainly the posterior head areas (occipital and temporal lobes) and anterior "watershed" areas. In this syndrome it is rare to observe a predominant involvement of the brainstem. We describe the clinical and radiological findings in a patient with brainstem involvement, discussing its pathophysiological features and possible differential diagnosis.

  13. Medusae Fossae Formation

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 10 April 2002) The Science This THEMIS visible image was acquired near 7o S, 172o W (188o E) and shows a remarkable martian geologic deposit known as the Medusae Fossae Formation. This Formation, seen here as the raised plateau in the upper two-thirds of the image, is a soft, easily eroded deposit that extends for nearly 1,000 km along the equator of Mars. In this region the deposit has been heavily eroded by the wind to produce a series of linear ridges called yardangs. These parallel ridges point in direction of the prevailing winds that carved them, and demonstrate the power of martian winds to sculpt the dry landscape of Mars. The Medusae Fossae Formation has been completely stripped from the surface in the lower third of the image, revealing a harder layer below that is more resistant to wind erosion. The easily eroded nature of the Medusae Fossae Formation suggests that it is composed of weakly cemented particles, and was most likely formed by the deposition of wind-blown dust or volcanic ash. Several ancient craters that were once completely buried by this deposit are being exposed, or exhumed, as the overlying Medusae Formation is removed. Very few impact craters are visible on this Formation, indicating that the surface seen today is relatively young, and that the processes of erosion are likely to be actively occurring. The Story Medusa of Greek mythology fame, the name-giver to this region, had snaky locks of hair that could turn a person to stone. Wild and unruly, this monster of the underworld could certainly wreak havoc on the world of the human imagination. As scary as she was, Medusa would have no advantage over the fierce, masterful winds blowing across Mars, which once carved the streaky, terrain at the top of this image. Wild and whipping, these winds have slowly eroded away the 'topsoil,' revealing ancient craters and other surface features they once covered. The loosely cemented particles of this 'topsoil' are likely made up of dust

  14. Clinico-radiological spectrum of reversible splenial lesions in children.

    PubMed

    Kashiwagi, Mitsuru; Tanabe, Takuya; Shimakawa, Shuichi; Nakamura, Michiko; Murata, Shinya; Shabana, Kousuke; Shinohara, Jun; Odanaka, Yutaka; Matsumura, Hideki; Maki, Koh; Okumura, Kenichi; Okasora, Keisuke; Tamai, Hiroshi

    2014-04-01

    Recently, many cases of children presenting reversible splenial lesions during febrile illness (RESLEF) have been reported; however, their overall clinico-radiological features are unclear. To describe the clinico-radiological features, we retrospectively reviewed the etiology (pathogen), clinical course, laboratory data, magnetic resonance imaging and electroencephalography (EEG) findings, therapy, and prognosis of 23 episodes in 22 children (1 child recurred) who presented neurological symptoms, with RESLEF. The etiologies (pathogens) varied. Seizure occurred in 7 episodes, disturbance of consciousness (DC) in 13, and delirious behavior in 18. Serum sodium levels <136 mEq/L were observed in 18 episodes. Lesions outside the splenium were found in 4 cases. Slow waves were observed on EEG in 10 episodes. Methylprednisolone pulse therapy was given in 7 cases. No case resulted in neurological sequelae. Among 23 episodes, clinically mild encephalitis/encephalopathy with a reversible splenial lesion (MERS) was diagnosed in 6 episodes, whereas non-MERS was observed in 17 episodes. No difference was observed in almost all the clinico-radiological features' data between the 2 groups. The largest differences were observed in the rate of purposeless movement, DC, extension of the abnormal lesions outside the splenium, and marked slowing of background activity on EEG. RESLEF exhibit a spectrum of clinico-radiological features. These results suggest that non-MERS and MERS both are a part of a larger pathological condition, which we have termed as RESLEF spectrum syndrome. Given the view that such a syndrome exists, the clinical characteristics and position of non-MERS and MERS become clear.

  15. Medusae Fossae Formation

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 16 April 2002) The Science This THEMIS visible image was acquired near 11o N, 159o W (201o E) and shows examples of the remarkable variations that can be seen in the erosion of the Medusae Fossae Formation. This Formation is a soft, easily eroded deposit that extends for nearly 1,000 km along the equator of Mars. In this region, like many others throughout the Medusae Fossae Formation, the surface has been eroded by the wind into a series of linear ridges called yardangs. These ridges generally point in direction of the prevailing winds that carved them, and demonstrate the power of martian winds to erode the landscape of Mars. The easily eroded nature of the Medusae Fossae Formation suggests that it is composed of weakly cemented particles, and was most likely formed by the deposition of wind-blown dust or volcanic ash. Within this single image it is possible to see differing amounts of erosion and stripping of layers in the Medusae Fossae Formation. Near the bottom (southern) edge of the image a rock layer with a relatively smooth upper surface covers much of the image. Moving upwards (north) in the image this layer becomes more and more eroded. At first there are isolated regions where the smooth unit has been eroded to produce sets of parallel ridges and knobs. Further north these linear knobs increase in number, and only small, isolated patches of the smooth upper surface remain. Finally, at the top of the image, even the ridges have been removed, exposing the remarkably smooth top of hard, resistant layer below. This sequence of layers with differing hardness and resistance to erosion is common on Earth and on Mars, and suggests significant variations in the physical properties, composition, particle size, and/or cementation of these martian layers. As is common throughout the Medusae Fossae Formation, very few impact craters are visible, indicating that the surface exposed is relatively young, and that the process of erosion may be active today

  16. Medusae Fossae Formation

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 16 April 2002) The Science This THEMIS visible image was acquired near 11o N, 159o W (201o E) and shows examples of the remarkable variations that can be seen in the erosion of the Medusae Fossae Formation. This Formation is a soft, easily eroded deposit that extends for nearly 1,000 km along the equator of Mars. In this region, like many others throughout the Medusae Fossae Formation, the surface has been eroded by the wind into a series of linear ridges called yardangs. These ridges generally point in direction of the prevailing winds that carved them, and demonstrate the power of martian winds to erode the landscape of Mars. The easily eroded nature of the Medusae Fossae Formation suggests that it is composed of weakly cemented particles, and was most likely formed by the deposition of wind-blown dust or volcanic ash. Within this single image it is possible to see differing amounts of erosion and stripping of layers in the Medusae Fossae Formation. Near the bottom (southern) edge of the image a rock layer with a relatively smooth upper surface covers much of the image. Moving upwards (north) in the image this layer becomes more and more eroded. At first there are isolated regions where the smooth unit has been eroded to produce sets of parallel ridges and knobs. Further north these linear knobs increase in number, and only small, isolated patches of the smooth upper surface remain. Finally, at the top of the image, even the ridges have been removed, exposing the remarkably smooth top of hard, resistant layer below. This sequence of layers with differing hardness and resistance to erosion is common on Earth and on Mars, and suggests significant variations in the physical properties, composition, particle size, and/or cementation of these martian layers. As is common throughout the Medusae Fossae Formation, very few impact craters are visible, indicating that the surface exposed is relatively young, and that the process of erosion may be active today

  17. Sirenum Fossae Trough

    NASA Technical Reports Server (NTRS)

    2000-01-01

    [figure removed for brevity, see original site]

    The Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) orbits the red planet twelve times each day. The number of pictures that MOC can take varies from orbit to orbit, depending upon whether the data are being stored in MGS's onboard tape recorder for playback at a later time, or whether the data are being sent directly back to Earth via a real-time radio link. More data can be acquired during orbits with real-time downlink.

    During real-time orbits, the MOC team often will take a few random or semi-random pictures in between the carefully-selected, hand-targeted images. On rare occasions, one of these random pictures will surprise the MOC team. The picture shown here is an excellent example, because the high resolution view (top) is centered so nicely on a trough and an adjacent, shallow crater that it is as if someone very carefully selected the target for MOC. The high-resolution view covers an area only 1.1 km (0.7 mi) wide by 2.3 km (1.4 mi) long. Hitting a target such as this with such a small image is very difficult to do, on purpose, because there are small uncertainties in the predicted orbit, the maps used to select targets, and the minor adjustments of spacecraft pointing at any given moment. Nevertheless, a very impressive image was received.

    The high resolution view crosses one of the troughs of the Sirenum Fossae near 31.2oS, 152.3oW. The context image (above) was acquired at the same time as the high resolution view on July 23, 2000. The small white box shows the location of the high resolution picture. The lines running diagonally across the context image from upper right toward lower left are the Sirenum Fossae troughs, formed by faults that are radial to the volcanic region of Tharsis. Both pictures are illuminated from the upper left. The scene shows part of the martian southern hemisphere nearly autumn.

  18. Arachnoid Cyst in the Middle Cranial Fossa Presenting with Pulsatile Exophthalmos: Case Report and Literature Review

    PubMed Central

    SAITO, Atsushi; KON, Hiroyuki; HARYU, Shinya; MINO, Masaki; SASAKI, Tatsuya; NISHIJIMA, Michiharu

    2014-01-01

    A 20-year-old woman suffered gradual progression of right pulsatile exophthalmos and slight headache. Computed tomography (CT) demonstrated outward and downward displacement of the right globe and an arachnoid cyst in the right middle cranial fossa associated with thinned and anterior protrusion of a bony orbit. Microscopic cystocisternotomy was performed and the cerebrospinal fluid (CSF) inside of the cyst communicated into the carotid cistern and cistern in the posterior cranial fossa. Pulsatile exophthalmos improved immediately after surgery. Arachnoid cyst in the middle cranial fossa presenting with exophthalmos is rare. Microscopic cystocisternotomy might successfully improve CSF flow and relieve exophthalmos. PMID:24305013

  19. Medusae Fossae Yardangs

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    Released 15 April 2003

    The Medusae Fossae formation is an enigmatic pile of eroding sediments that spans over 5000 km in discontinuous masses along the martian equator. The yardang ridges, formed from the scouring action of windblown sand, are a characteristic feature of this formation. In this image, there is evidence for a period of erosion when winds scoured the surface at nearly right angles to the prominent yardang direction.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

    Image information: VIS instrument. Latitude -5.1, Longitude 184.4 East (175.6 West). 19 meter/pixel resolution.

  20. Medusae Fossae Formation

    NASA Technical Reports Server (NTRS)

    1998-01-01

    An exotic terrain of wind-eroded ridges and residual smooth surfaces are seen in one of the highest resolution images ever taken of Mars from orbit. The Medusae Fossae formation is believed to be formed of the fragmental ejecta of huge explosive volcanic eruptions. When subjected to intense wind-blasting over hundreds of millions of years, this material erodes easily once the uppermost tougher crust is breached. In the Mars Orbiter Camera (MOC) image shown on the right, the crust, or cap rock, can be seen in the upper right part of the picture. The finely-spaced ridges are similar to features on Earth called yardangs, which are formed by intense winds plucking individual grains from, and by wind-driven sand blasting particles off, sedimentary deposits.

    The MOC image was taken on October 30, 1997 at 11:05 AM PST, shortly after the Mars Global Surveyor spacecraft's 31st closest approach to Mars. The image covers an area 3.6 X 21.5 km (2.2 X 13.4 miles) at 3.6 m (12 feet) per picture element--craters only 11 m (36 feet, about the size of a swimming pool) across can be seen. The context image (left; the best Viking view of the area; VO 1 387S34) has a resolution of 240 m/pixel, or 67 times lower resolution than the MOC frame.

    Malin Space Science Systems (MSSS) and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

  1. Clay at Nili Fossae

    NASA Technical Reports Server (NTRS)

    2006-01-01

    This image of the Nili Fossae region of Mars was compiled from separate images taken by the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) and the High-Resolution Imaging Science Experiment (HiRISE), two instruments on NASA's Mars Reconnaissance Orbiter. The images were taken at 0730 UTC (2:30 a.m. EDT) on Oct. 4, 2006, near 20.4 degrees north latitude, 78.5 degrees east longitude. CRISM's image was taken in 544 colors covering 0.36 to 3.92 micrometers, and shows features as small as 18 meters (60 feet) across. HiRISE's image was taken in three colors, but its much higher resolution shows features as small as 30 centimeters (1 foot) across.

    CRISM's sister instrument on the Mars Express spacecraft, OMEGA, discovered that some of the most ancient regions of Mars are rich in clay minerals, formed when water altered the planet's volcanic rocks. From the OMEGA data it was unclear whether the clays formed at the surface during Mars' earliest history of if they formed at depth and were later exposed by impact craters or erosion of the overlying rocks. Clays are an indicator of wet, benign environments possibly suitable for biological processes, making Nili Fossae and comparable regions important targets for both CRISM and HiRISE.

    In this visualization of the combined data from the two instruments, the CRISM data were used to calculate the strengths of spectral absorption bands due to minerals present in the scene. The two major minerals detected by the instrument are olivine, a mineral characteristic of primitive igneous rocks, and clay. Areas rich in olivine are shown in red, and minerals rich in clay are shown in green. The derived colors were then overlayed on the HiRISE image.

    The area where the CRISM and HiRISE data overlap is shown at the upper left, and is about 5 kilometers (3 miles) across. The three boxes outlined in blue are enlarged to show how the different minerals in the scene match up with different landforms. In the image

  2. Mandibular fossa morphology in the Ngandong and Sambungmacan fossil hominids.

    PubMed

    Durband, Arthur C

    2008-10-01

    There has been debate in recent years concerning the significance of the mandibular fossa morphology in the Ngandong and Sambungmacan hominids. These fossils lack a postglenoid process and their squamotympanic fissure runs along the apex of the fossa for its entire length. This configuration differs from that seen in other fossil and modern humans, which have a prominent postglenoid process and a squamotympanic fissure that takes a more posterior course that does not lie in the apex of the fossa. Some recent studies have suggested that the Ngandong and Sambungmacan hominids are not unique in their expression of these characteristics, and that they can also be found in other fossil crania from Africa and Indonesia. The present study reexamines these morphologies in an effort to better understand their distribution in the hominid fossil record. The results confirm that the lack of a prominent postglenoid process in combination with a squamotympanic fissure that lies wholly in the apex of the mandibular fossa along its entire length is indeed autapomorphic for the Ngandong and Sambungmacan fossils. This finding, in conjunction with work on other nonmetric features in these hominids, suggests that at least two hominid morphs, possibly representing separate species, were present on Java during the Pleistocene. In addition, if this apparent autapomorphy is confirmed, then it is also unlikely that the Ngandong hominids contributed to the gene pool of modern humans.

  3. Posterior peritoneal recesses: assessment using CT

    SciTech Connect

    Rubenstein, W.A.; Auh, Y.H.; Zirinsky, K.; Kneeland, J.B.; Whalen, J.P.; Kazam, E.

    1985-08-01

    Intraperitoneal compartments may extend posteriorly to the level of known retroperitoneal structures at several locations within the abdomen. These locations include the posterior subhepatic or hepatorenal space, the splenorenal space, the retropancreatic recess, the paracolic gutters, and the pararectal fossae. Because of their posterior location, fluid collections within these compartments may be mistaken radiologically for retroperitoneal masses. The sectional anatomy of these spaces and particularly their appearance on computed tomographic scans, are illustrated in this paper.

  4. Acoustic Schwannoma Presenting as Acute Posterior Fossa Hematoma

    PubMed Central

    Ghobashy, Ashraf; Loveren, Harry van

    1993-01-01

    Acoustic schwannomas usually present with gradually progressive unilateral sensorineural hearing loss. As the tumor enlarges, symptoms and signs develop when the adjacent cranial nerves, cerebelhim, and/or brainstem become compressed. Rarely, acoustic tumors present with acute subarachnoid or intratumoral hemorrhage. Of the 12 cases of acoustic schwannoma with tumoral hemorrhage presented in the literature of which we are aware, this is the third such case of a patient presenting with spontaneous pure intratumoral hemorrhage and the first such case presenting with sudden multiple cranial nerve palsies, The purpose of this report is to increase the awareness of this rare form of presentation of acoustic schwannoma in the hope of achieving better preservation of cranial nerves. ImagesFigure 1Figure 2Figure 3 PMID:17170903

  5. A 15 year old boy with a posterior fossa tumor.

    PubMed

    Chapman, Erin M; Ranger, Adrianna; Lee, Donald H; Hammond, Robert R

    2009-04-01

    A 15 year old male presented with hydrocephalus from a tectal mass obstructing the cerebral aqueduct and upper fourth ventricle. The solid-cystic partly enhancing mass proved to be a pigmented pleomorphic xanthoastrocytoma, the third such example reported. The lesion revealed typical features of a PXA with the unusual addition of intracytoplasmic melanin in select lesional cells. Melanin pigment production is uncommon in glial tumors and of uncertain significance. The present case is recurrence-free one year post-operatively.

  6. Surgical Anatomy of the Extended Middle Cranial Fossa Approach

    PubMed Central

    Arìstegui, Miguel; Cokkeser, Yasar; Saleh, Essam; Naguib, Maged; Landolfi, Mauro; Taibah, Abdel; Sanna, Mario

    1994-01-01

    The extended middle cranial fossa approach includes removal of the petrous bone from its subtemporal surface in order to expose widely the internal auditory canal and the posterior fossa dura around its porus while preserving all the important and closely related anatomical structures. We have dissected 25 temporal bones and five fresh cadavers in order to define the limits of this approach. Measurements were obtained between the different structures to find reliable angles and distances that could guide working in this area. A new method of identification of the internal auditory canal is discussed based on the measurements taken. The results of the present work showed wide variations in the different structures. The arcuate eminence was coincident with the superior semicircular canal in only 48% of bones. Dehiscence of the geniculate ganglion and of the internal carotid artery was noted in 16% and 20% of specimens, respectively. The angles measured between the different structures showed great variations. However, the angle between the internal auditory canal and superior petrosal sinus was constant. Though the extended middle cranial fossa is a versatile approach, it affords a limited access to the cerebellopontine angle. A thorough understanding of the complex and variable anatomy of this area is necessary should this approach be utilized. ImagesFigure 1p183-bFigure 2Figure 3Figure 4Figure 5 PMID:17171170

  7. Posterior Reversible Encephalopathy Syndrome

    PubMed Central

    Algahtani, Abdulhadi; Aldarmahi, Ahmad; Hmoud, Mohammed; Marzuk, Yousef; Shirah, Bader

    2016-01-01

    Objectives: Posterior reversible encephalopathy syndrome (PRES) is a clinicoradiological syndrome characterized by headache, altered mental status, seizures, or loss of vision. In this study, we report the largest series of PRES coming from Saudi Arabia and explore the etiology, clinical presentation, and outcome. We also report new imaging findings associated with this condition. Methods: We performed a retrospective study of all cases of PRES admitted to King Abdulaziz Medical City, Jeddah, Saudi Arabia, between the years 2005 and 2015. A neurologist reviewed all charts and analyzed the clinical presentations, etiological factors, and outcomes, and a neuroradiologist reviewed the imaging studies. Only patients with clinical and imaging features consistent with PRES were included in the study. Results: We collected 31 patients who had clinical and radiological features consistent with PRES. Females were more affected than males (18 females and 13 males), and patients’ age ranged from 6 to 95 years, with a mean of 38.3 years. Patients were treated by removing the precipitating causes and treating the underlying conditions. Resolution of neurologic signs occurred within 2 to 3 weeks in all patients. Conclusion: In our opinion, PRES itself is usually a benign condition with complete recovery if the condition is recognized early and managed appropriately. Although clinical signs are nonspecific, the constellation of symptoms including headache, visual problems, seizures, and altered level of consciousness should suggest the possibility of PRES, especially in high-risk group. Abnormalities on magnetic resonance imaging are often characteristic and may be the first clue to the diagnosis. PMID:28042366

  8. Acheron Fossae in Visible Light

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This visible-light image, taken by the thermal emission imaging system's camera on NASA's 2001 Mars Odyssey spacecraft, shows the highly fractured, faulted and deformed Acheron Fossae region of Mars. The scarps visible in this image are approximately one kilometer (3,300 feet) high, based on topography derived from the laser altimeter instrument on Mars Global Surveyor.

    Dark streaks only 50 meters (164 feet) across can be seen on some of the cliff faces. These streaks may be formed when the pervasive dust mantle covering this region gives way on steep slopes to create dust avalanches.

    The image also shows impact craters as small as 500 meters (1,640 feet) in diameter, as well as smooth and textured plains.

    Acheron Fossae is located 1,050 kilometers (650 miles) north of the large shield volcano Olympus Mons. This image covers an area about 18 by 9 kilometers (11 by 6 miles) centered at 37 degrees north, 131 degrees west. North is to the top of this image, which was acquired on February 19,2002, at about 3:15 p.m. local Martian time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The thermal emission imaging system was provided by Arizona State University, Tempe. Lockheed Martin Astronautics, Denver, is the prime contractor for the project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  9. Spectrum of clinicoradiological findings in spinal cord infarction: Report of three cases and review of the literature

    PubMed Central

    Sivadasan, Ajith; Alexander, Mathew; Patil, Anil K.; Mani, Sunithi

    2013-01-01

    Spinal cord infarction (SCI) often remains undiagnosed due to infrequent occurrence and lack of established diagnostic procedures. The unique pattern of blood supply explains the heterogeneity of clinical presentation. We present three cases of SCI to highlight the varied spectrum of clinicoradiological findings. The first patient had posterior spinal artery infarction, and spine imaging showed infarction of adjacent vertebral body, which is usually rare. The second patient had anterior spinal artery infarction and the cANCA titers were elevated. The third patient had a pure motor quadriparesis. Initial imaging did not show any cord infarction, but signal changes were noted on serial imaging. Fibrocartilagenous embolism (FCE) seems the most likely etiology in the first and third cases. A high index of clinical suspicion is necessary for prompt diagnosis. Sensitivity of the initial magnetic resonance imaging remains limited, necessitating serial follow-up scans. Infarction of the adjacent vertebral body is a useful confirmatory sign. Fat suppression images can delineate the marrow signal changes better. Elderly patients with vascular risk factors and degenerative discs need to avoid mechanical triggers that predispose to FCE. Younger patients with SCI will need evaluation for cardioembolic source and vasculitis. PMID:23956562

  10. Nili Fossae Resource and Science ROIs

    NASA Astrophysics Data System (ADS)

    Markle, L. M.

    2015-10-01

    The Nili Fossae region presents multiple resource and science ROIs for establishing a permanent colony on Mars. Water ice appears to cover a large are and multiple geological formations provide opportunity for science missions.

  11. Tumors of the Infratemporal Fossa

    PubMed Central

    Tiwari, Rammohan; Quak, Jasper; Egeler, Saskia; Smeele, Ludi; Waal, Isaac v.d.; Valk, Paul v.d.; Leemans, Rene

    2000-01-01

    Neoplastic processes involving the infratemporal fossa may originate from the tissues in the region, but more often are the result of extension from neighboring structures. Metastatic lesions located in the region are rarely encountered. Because of its concealed localization, tumors may remain unnoticed for some time. Clinical signs and symptoms often arise late, are insidious, and may be mistakenly attributed to other structures. The close proximity of the area to the intracranial structures, the orbit, the paranasal sinuses, the nasopharynx, and the facial area demands careful planning of surgical excision and combined procedures may be called for. Modern imaging techniques have made three-dimensional visualization of the extent of the pathology possible. Treatment depends on the histopathology and staging of the tumor. Several surgical approaches have been developed over the years. Radical tumor excision with preservation of the quality of life remain the ultimate goal for those tumors where surgery is indicated. Experience over a decade with various pathologies is presented. ImagesFigure 1p6-bFigure 2Figure 3 PMID:17171095

  12. Trochanteric fossa or piriform fossa of the femur: time for standardised terminology?

    PubMed

    Ansari Moein, C M S; Gerrits, P D; ten Duis, H J

    2013-06-01

    Piriform fossa, trochanteric fossa and greater trochanteric tip have each been described as entry points for antegrade femoral nailing. However, the terminology used for these entry points is confusing. The accuracy of the entry point nomenclature in published text and illustrations was recorded in this review study. The trochanteric fossa, a deep depression at the base of the femoral neck is indicated as 'piriform fossa' in the vast majority of the publications. Other publications indicate the insertion site of the tendon of the piriformis muscle on the greater trochanteric tip as 'piriform fossa'. As a result of recurrent terminology error and consistent reproductions of it, the recommended entry point in literature is confusing and seems to need standardisation. The piriform fossa does not appear to exist in the femoral region. The trochanteric fossa is the standard entry point which most surgeons recommend for facilitating a standard straight intramedullary nail, as is in line with the medullary canal. The greater trochanteric tip is the lateral entry point for intramedullary nails with a proximal lateral bend.

  13. Correlation of replicating cells and osteogenesis in the glenoid fossa during stepwise advancement.

    PubMed

    Rabie, A B M; Wong, Louise; Hägg, Urban

    2003-05-01

    The purposes of this study were to quantify the number of replicating mesenchymal cells and to correlate it with the amount of new bone formed in the glenoid fossa during stepwise advancement. We randomly divided 250 female Sprague-Dawley rats, 35 days old, into 10 control groups (n = 5) and 20 experimental groups (n = 10). Fifty rats from the stepwise experimental group received initial advancement of 2 mm and another 1.5 mm of advancement on day 30 by the addition of veeners. On days 3, 7, 14, 21, 30, 33, 37, 44, 51, and 60, the rats were killed. One hour before that, the rats were injected with bromodeoxyuridine (BrdU) intravenously. We cut 7-microm tissue sections through the glenoid fossa sagittally and stained them with anti-BrdU antibody to evaluate the number of replicating mesenchymal cells. During the first advancement, the number of replicating cells in the posterior region of the glenoid fossa showed a significant increase compared with natural growth, but a significant decrease compared with 1-step advancement. On the second advancement, however, an increase in the number of replicating cells was observed on day 37 with a subsequent and significant increase in bone formation on day 44. Mandibular advancement conducted in a stepwise fashion increases the number of replicating mesenchymal cells in the glenoid fossa. However, a minimum threshold of strain must first be exceeded before these mesenchymal cells can differentiate to ultimately form new bone.

  14. Infratemporal fossa abscess: a diagnostic dilemma.

    PubMed

    Kamath, M Panduranga; Bhojwani, Kiran M; Mahale, Ajit; Meyyappan, Hari; Abhijit, Kumar

    2009-05-01

    An abscess in the infratemporal fossa is a rare complication of dental extraction. Although it is a recognized entity, only a handful of cases have been reported in the literature. We describe a case of abscess in the infratemporal fossa of a 55-year-old woman with noninsulin-dependent (type 2) diabetes who presented with left-sided facial pain and marked trismus. The abscess was managed successfully with external drainage. We have made an attempt to comprehensively review the literature on this rare condition, with special emphasis on its anatomic complexity and varied clinical presentation, and we provide a detailed discussion of the diagnosis and management of this condition.

  15. 21 CFR 872.3950 - Glenoid fossa prosthesis.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Glenoid fossa prosthesis. 872.3950 Section 872...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3950 Glenoid fossa prosthesis. (a) Identification. A glenoid fossa prosthesis is a device that is intended to be implanted in the...

  16. 21 CFR 872.3950 - Glenoid fossa prosthesis.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Glenoid fossa prosthesis. 872.3950 Section 872...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3950 Glenoid fossa prosthesis. (a) Identification. A glenoid fossa prosthesis is a device that is intended to be implanted in the...

  17. 21 CFR 872.3950 - Glenoid fossa prosthesis.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Glenoid fossa prosthesis. 872.3950 Section 872...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3950 Glenoid fossa prosthesis. (a) Identification. A glenoid fossa prosthesis is a device that is intended to be implanted in the...

  18. 21 CFR 872.3950 - Glenoid fossa prosthesis.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Glenoid fossa prosthesis. 872.3950 Section 872...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3950 Glenoid fossa prosthesis. (a) Identification. A glenoid fossa prosthesis is a device that is intended to be implanted in the...

  19. Striae in the popliteal fossa (image)

    MedlinePlus

    ... syndrome. Most pregnant women experience striae at some point during their pregnancy. This picture shows striae in the popliteal fossa (the area on the back side of the leg at the knee joint). When the striae first appear they have a ...

  20. Posterior reversible encephalopathy syndrome following a scorpion sting.

    PubMed

    Porcello Marrone, Luiz Carlos; Marrone, Bianca Fontana; Neto, Felipe Kalil; Costa, Francisco Cosme; Thomé, Gustavo Gomes; Aramburu, Martin Brandolt; Schilling, Lucas Porcello; Pascoal, Tharick Ali; Gadonski, Giovani; Huf Marrone, Antônio Carlos; da Costa, Jaderson Costa

    2013-10-01

    Posterior reversible encephalopathy syndrome (PRES) is a clinicoradiologic entity not yet understood, that is present with transient neurologic symptoms and particular radiological findings. The most common imaging pattern in PRES is the presence of edema in the white matter of the posterior portions of both cerebral hemispheres. The cause of PRES is unclear. We report a case of 13-year-old male who was stung by a scorpion and developed a severe headache, visual disturbance, and seizures and had the diagnosis of PRES with a good outcome. Numerous factors can trigger this syndrome, most commonly: acute elevation of blood pressure, abnormal renal function, and immunosuppressive therapy. There are many cases described showing the relationship between PRES and eclampsia, transplantation, neoplasia and chemotherapy treatment, systemic infections, renal disease acute, or chronic. However, this is the first case of PRES following a scorpion sting.

  1. [Cochlear implantation through the middle fossa approach].

    PubMed

    Szyfter, W; Colletti, V; Pruszewicz, A; Kopeć, T; Szymiec, E; Kawczyński, M; Karlik, M

    2001-01-01

    The inner part of cochlear implant is inserted into inner ear during surgery through mastoid and middle ear. It is a classical method, used in the majority cochlear centers in the world. This is not a suitable method in case of chronic otitis media and middle ear malformation. In these cases Colletti proposed the middle fossa approach and cochlear implant insertion omitting middle ear structures. In patient with bilateral chronic otitis media underwent a few ears operations without obtaining dry postoperative cavity. Cochlear implantation through the middle fossa approach was performed in this patient. The bone fenster was cut, temporal lobe was bent and petrosus pyramid upper surface was exposed. When the superficial petrosal greater nerve, facial nerve and arcuate eminence were localised, the cochlear was open in the basal turn and electrode were inserted. The patient achieves good results in the postoperative speech rehabilitation. It confirmed Colletti tesis that deeper electrode insertion in the cochlear implantation through the middle fossa approach enable use of low and middle frequencies, which are very important in speech understanding.

  2. Effect of Incremental Endoscopic Maxillectomy on Surgical Exposure of the Pterygopalatine and Infratemporal Fossae

    PubMed Central

    Upadhyay, Smita; Dolci, Ricardo L. L.; Buohliqah, Lamia; Fiore, Mariano E.; Filho, Leo F.S. Ditzel; Prevedello, Daniel M.; Otto, Bradley A.; Carrau, Ricardo L.

    2015-01-01

    Objective Access to the pterygopalatine and infratemporal fossae presents a significant surgical challenge, owing to their deep-seated location and complex neurovascular anatomy. This study elucidates the benefits of incremental medial maxillectomies to access this region. We compared access to the medial aspect of the infratemporal fossa provided by medial maxillectomy, anteriorly extended medial maxillectomy, endoscopic Denker approach (i.e., Sturmann-Canfield approach), contralateral transseptal approach, and the sublabial anterior maxillotomy (SAM). Methods We studied 10 cadaveric specimens (20 sides) dissecting the pterygopalatine and infratemporal fossae bilaterally. Radius of access was calculated using a navigation probe aligned with the endoscopic line of sight. Area of exposure was calculated as the area removed from the posterior wall of maxillary sinus. Surgical freedom was calculated by computing the working area at the proximal end of the instrument with the distal end fixed at a target. Results The endoscopic Denker approach offered a superior area of exposure (8.46 ± 1.56 cm2) and superior surgical freedom. Degree of lateral access with the SAM approach was similar to that of the Denker. Conclusion Our study suggests that an anterior extension of the medial maxillectomy or a cross-court approach increases both the area of exposure and surgical freedom. Further increases can be seen upon progression to a Denker approach. PMID:26949591

  3. Clinico-radiological diagnosis and grading of rapidly progressive osteoarthritis of the hip

    PubMed Central

    Zazgyva, Ancuţa; Gurzu, Simona; Gergely, István; Jung, Ioan; Roman, Ciprian O.; Pop, Tudor S.

    2017-01-01

    Abstract Due to the current lack of standard definitions for rapidly progressive osteoarthritis of the hip (RPOH) in the literature, this observational study aimed to describe new diagnostic criteria and a grading system for the disease. From a consecutive series of patients undergoing total hip replacement, 2 groups were selected: 1 with RPOH and 1 with primary hip osteoarthritis (POH), and their clinical, paraclinical, and demographic data were compared. The newly proposed clinico-radiological diagnostic criteria are based on characteristics of pain, joint mobility, and radiological assessment. The radiological grading system's inter- and intraobserver reliability was assessed through serial evaluations by 2 blinded reviewers. From the total 863 cases, 82 cases (9.5%) of RPOH were identified and compared with 107 cases of POH. Mean age and disease bilaterality were similar, with a predominance of female patients in the RPOH group (P = 0.03). There were significant differences between the 2 groups in disease onset and aggravation, and intraoperative blood loss. The grading system showed significant inter- and intraobserver agreement (weighted kappa 0.93, and 0.89). Our study presents distinctive, easily recognizable clinico-radiological characteristics of RPOH and confirmed the inter- and intraobserver reliability of the newly proposed grading system. PMID:28328832

  4. Bullet removal from the infratemporal fossa

    PubMed Central

    Merza, Ahmed Maki

    2016-01-01

    War injuries are the cornerstone of maxillofacial surgery, and it led to the initiation and development of this specialty, and each case represents a challenge to the surgeon who deals with it. In this article, we present a 30-year-old male patient who was referred to our emergency department complaining of gunshot wound, severe pain, and limitation in mouth opening. Preoperative imaging showed a bullet with a very long path lodged in the infratemporal fossa. Three different approaches with the aid of C-arm imaging system were used for the removal of this bullet; the last approach was the successful one. PMID:28299274

  5. An unusual foreign body in the infratemporal fossa

    PubMed Central

    Ramdas, Sharad

    2016-01-01

    Infratemporal fossa injuries are uncommon and often go undetected presenting later with complications. We present a case of an infratemporal fossa penetrating injury with a ball point spring following a vehicular accident. Post-traumatic trismus even following supposedly trivial injury in the area should raise suspicion of possible injury in this location. PMID:27833297

  6. Penetration of the mandibular condyle into the middle cranial fossa: report of a case in a 6-year-old girl.

    PubMed

    DeFabianis, P

    2001-01-01

    Reported cases of dislocation of the mandibular condyle into the middle cranial fossa are rare. Treatment of this injury should be individualized and should take in account the age of the patient, growth potential, the degree of glenoid fossa destruction, the risk of ankylosis and the risk of further cranial injury. In children, functional therapy is aimed at helping the restoration of posterior facial height, good occlusal relations and function. Long-term follow-up is mandatory. Surgery may be required later to correct asymmetrical growth or developing ankylosis. This article describes a case of condylar penetration into the middle cranial fossa in a six-year-old child and the treatment performed to minimize consequences on occlusion and facial development.

  7. Clinico-radiological correlation of nutcracker syndrome: a single centre experience.

    PubMed

    Taktak, Aysel; Hakan Demirkan, Tulin; Acar, Banu; Gu R, Gökçe; Köksoy, Adem; Uncu, Nermin; Çaycı, Fatma Ş; Çakar, Nilgu N

    2017-04-01

    The term nutcracker syndrome (NS) refers to the compression of left renal vein between the aorta and the superior mesenteric artery (SMA) causing renal venous hypertension. The symptoms vary from asymptomatic hematuria to severe pelvic congestion. The purpose of this study is to evaluate the clinical characteristics of patients with NS and the correlation between clinical and laboratory findings with Doppler sonographic measurements. Sixty-three patients were evaluated (19 boys and 44 girls) since January 2004 to January 2014. The mean age of the patients was 12.21 ± 3.21 years (range 7-17). Hematuria and proteinuria disappeared during the follow up of 9/63 patients. These nine patients showed statistically significant difference in upright SMA angles (p= 0.035). Doppler sonographic evaluation is a non-invasive method for diagnosis NS. Upright SMA angle measurement is more efficient than supine SMA angle measurement on clinicoradiological correlation.

  8. Pulmonary Alveolar Microlithiasis "Stone Lungs": A Case of Clinico-Radiological Dissociation.

    PubMed

    Chu, Andrew; Shaharyar, Sameer; Chokshi, Binna; Bhardwaj, Nikhil

    2016-08-24

    Pulmonary alveolar microlithiasis (PAM) is a rare infiltrative lung disease characterized by deposition of spherical calcium phosphate microliths called calcospherites within the alveoli. PAM was first described by Friedrich in 1856 and then by Harbitz in 1918. The disease pathogenesis is based on mutations in the SLC34A2 gene that encodes for the Type IIb sodium-phosphate cotransporter. The majority of the patients are diagnosed at an early age, usually between the ages of 20 and 40 years. The hallmark of this disease is a striking dissociation between the radiological findings and the mild clinical symptoms.  We report a case of 35-year-old woman who presented post-motor vehicle accident with back pain and with minimal dyspnea on exertion. The final diagnosis was made after computed tomography and lung biopsy. The present case exhibits the remarkable clinico-radiological dissociation with complete calcification of the lungs on radiographic images with a relatively mild clinical presentation.

  9. Diffuse Parenchymal Lung Diseases with Clinicoradiological Discordance: Role of Transbronchial Lung Biopsy as a Diagnostic Tool - An Observational Study

    PubMed Central

    Narayan, Kiran Vishnu; Edakalavan, Jyothi; Kumar, Neethu Kesava

    2016-01-01

    Introduction The diagnosis of Diffuse Parenchymal Lung Disease (DPLD) requires a multidisciplinary approach with reconciliation of clinicoradiological and histopathological data. But when the preliminary clinicoradiological profile fails to suggest a diagnosis, an adequate lung biopsy specimen with meticulous histological examination and a multidisciplinary approach usually yields results. There is also a high chance of sampling error due to patchy and heterogeneous involvement of the disease process and due to the small volume of tissue taken. As seen in our study, Trans-Bronchial Lung Biopsy (TBLB) if performed by an experienced bronchoscopist can be done as an outpatient procedure yielding adequate specimens for diagnosis and guide effective treatment in these patients. Aim To study the utility and diagnostic yield of TBLB in DPLD patients when there is clinicoradiological discordance. Materials and Methods The current retrospective observational study was undertaken in the Institute of Chest Diseases, Government Medical College, Kozhikode, Kerala, India, from January 2012 to December 2014. Out of 169 DPLD patients who attended the tertiary care centre, 66 patients without a definite diagnosis by clinicoradiological assessment were included in the study. They underwent TBLB using a fibre-optic video bronchoscope. An open lung biopsy was advised if the TBLB did not yield a definite diagnosis. Results Among the 66 patients, histopathological confirmation was obtained in 51 patients, 39 of which were by TBLB (59%). Few diagnoses like invasive adenocarcinoma, Pneumocystis jirovecii pneumonia and Aspergillus infection were least expected. Conclusion TBLB if performed correctly can be an effective intervening modality in establishing the diagnosis of DPLD before going for an invasive surgical biopsy. PMID:28050417

  10. Mineral Spectra from Nili Fossae, Mars

    NASA Technical Reports Server (NTRS)

    2008-01-01

    Spectra collected by the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) indicate the presence of three distinct minerals. The graphed information comes from an observation of terrain in the Nili Fossae area of northern Mars. CRISM is one of six science instruments on NASA's Mars Reconnaissance Orbiter.

    Iron-magnesium smectite clay is formed through alteration of rocks by liquid water and is characterized by distinctive absorptions at 1.4, 1.9, and 2.3 micrometers due to water (H2O) and OH in the atomic structure of the mineral. Olivine is an iron magnesium silicate and primary igneous mineral, and water is not in its structure. Its spectrum is characterized by a strong and broad absorption at 1.0 micrometer due to ferrous iron (Fe2+). Carbonate is an alteration mineral identified by the distinctive paired absorptions at 2.3 and 2.5 micrometers. The precise band positions at 2.31 and 2.51 micrometers identify the carbonate at this location as magnesium carbonate. The broad 1.0 micrometer band indicates some small amount of ferrous iron is also present and the feature at 1.9 micrometers indicates the presence of water. CRISM researchers believe the magnesium carbonate found in the Nili Fossae region formed from alteration of olivine by water.

    The data come from a CRISM image catalogued as FRT00003E12. The spectra shown here are five-pixel-by-five-pixel averages of CRISM L-detector spectra taken from three different areas within the image that have then been ratioed to a five-pixel-by-five-pixel common denominator spectrum taken from a spectrally unremarkable area with no distinctive mineralogic signatures. This technique highlights the spectral contrasts between regions due to their unique mineralogy. The spectral wavelengths near 2.0 micrometers are affected by atmospheric absorptions and have been removed for clarity.

    NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology, Pasadena, manages the Mars

  11. Functional morphology of the Neandertal scapular glenoid fossa.

    PubMed

    Macias, Marisa E; Churchill, Steven E

    2015-01-01

    Neandertals and Homo sapiens are known to differ in scapular glenoid fossa morphology. Functional explanations may be appropriate for certain aspects of glenoid fossa morphology; however, other factors--e.g., allometry, evolutionary development--must be addressed before functional morphology is considered. Using three-dimensional geometric morphometrics, shape of the scapular glenoid fossa was compared among Neandertals, early and recent modern humans, chimpanzees, orangutans, Australopithecus afarensis, and Au. sediba. Permutation analysis revealed that side, sex, and lifestyle did not correlate with shape. Of the features we found to differ between groups, anterior glenoid rim morphology and fossa curvature did not correlate with the aforementioned shape variables; thus, a functional explanation is appropriate for these components of glenoid fossa shape. Shared morphology among recent humans and chimpanzees (to the exclusion of Neandertals and orangutans) suggests independent forces contributing to these morphological configurations. Potential explanations include adaptations to habitual behavior and locomotor adaptations in the scapulae of recent humans and chimpanzees; these explanations are supported by clinical and experimental literature. The absence of these morphological features in Neandertals may support the lack of these selective forces on their scapular glenoid fossa morphology.

  12. An unusual case of posterior reversible encephalopathy syndrome in a patient being weaned from intrathecal morphine

    PubMed Central

    Van Aalst, Jasper; Teernstra, Onno P; Weber, Wim E; Rijkers, Kim

    2016-01-01

    Posterior reversible encephalopathy syndrome (PRES) is a clinicoradiological entity based on clinical signs, including headache, visual abnormalities, and seizures, and radiological abnormalities mostly consisting of vasogenic brain edema predominantly in the posterior parietal-temporal-occipital regions. PRES typically develops in the setting of a significant “ systemic process”, including preeclampsia, transplantation, infection/sepsis/shock, autoimmune disease, and cancer chemotherapy, in which hypertension often plays an important role. We present a case of PRES in a 63-year-old female patient with an infected intrathecal morphine pump on a cocktail of antibiotics, morphine, clonidine, diazepam, and amitriptyline. It is the first PRES case in a chronic pain patient, which illustrates that PRES can occur in the absence of any of the established risk factors. We hypothesize it may have been caused by antibiotic treatment in our patient. PMID:27274314

  13. Recurarization in a successfully managed case of posterior reversible encephalopathy syndrome (PRES) for emergency caesarean section

    PubMed Central

    Parikh, Suchita; Tavri, Snehlata; Mohite, Shubha

    2016-01-01

    Posterior reversible encephalopathy syndrome (PRES) is a clinicoradiologic syndrome of headache, visual changes, altered mental status and seizures with radiologic findings of posterior cerebral white matter edema. It is seen in hypertensive encephalopathy, renal failure, and autoimmune disorders or in patients on immunosuppressants. We report a case of 24-year-old primigravida who presented at term with sudden onset hypertension, neurological deficits, and an episode of the visual blackout. Magnetic resonance imaging showed features suggestive of PRES. She was posted for emergency lower segment cesarean section. General anesthesia was administered and blood pressure managed with antihypertensives. Postoperatively, she developed acute respiratory depression after prophylactic administration of injection magnesium sulfate. This case highlights that good clinical acumen along with early neuroimaging helps in prompt diagnosis, treatment and prevention of long-term neurological sequelae in PRES and the anesthetic implications of administering magnesium sulfate in the immediate post neuromuscular block reversal phase. PMID:27212776

  14. Computed Tomographic Evaluation of Condylar Symmetry and Condyle-Fossa Relationship of the Temporomandibular Joint in Subjects with Normal Occlusion and Malocclusion: A Comparative Study

    PubMed Central

    Ponnada, Swaroopa Rani; Gaddam, Kranthi Praveen Raju; Perumalla, Kiran; Khan, Imran; Mohammed, Naqeed Abdul

    2017-01-01

    Introduction The relationship of the condyle and the mandibular fossa differs in shape with type of malocclusion and skeletal pattern. A review of literature shows till date there are no studies on Temporomandibular Joint (TMJ) condyle-fossa relation to the type of malocclusion based on growth pattern. Computed Tomography (CT) provides optimal imaging of the osseous components of the TMJ. Aim The purpose of this study was to investigate the condyle-fossa relationship and the dimensional and positional symmetries between the right and left condyles in subjects with normal occlusion and malocclusion in different growth patterns utilizing the CT scans of the TMJ. Materials and Methods Sixty subjects with age group of 18-30 years were selected for the study. The sample was divided into three groups based on overbite and growth pattern. The groups included 20 subjects with normal occlusion and average growth pattern, 20 patients with horizontal growth pattern and deep bite, 20 patients with vertical growth pattern and deep bite. The depth of the mandibular fossa, the condyle-fossa relationship, and the concentric position of the condyles were evaluated by the images obtained from the sagittal slices. ANOVA was performed to assess the significance. If it was found significant, post-hoc Tukey’s test was performed to see which two groups were statistically significant. Results No statistically significant difference was found in the anterior joint space and the superior joint space in horizontal and vertical growers with deep bite. Statistically significant (p <0.05) posterior positioning of the condyles was observed (nonconcentric positioning) in vertical growers with deep bite. Conclusion There is a significant change in the position of the condyle in vertical growers compared to average and horizontal growers. Left condyle is more anteriorly placed than the right condyle in all the three groups. There is no significant change in the vertical depth of the mandibular

  15. Medusae Fossae Formation - High Resolution Image

    NASA Technical Reports Server (NTRS)

    1998-01-01

    An exotic terrain of wind-eroded ridges and residual smooth surfaces are seen in one of the highest resolution images ever taken of Mars from orbit. The Medusae Fossae formation is believed to be formed of the fragmental ejecta of huge explosive volcanic eruptions. When subjected to intense wind-blasting over hundreds of millions of years, this material erodes easily once the uppermost tougher crust is breached. The crust, or cap rock, can be seen in the upper right part of the picture. The finely-spaced ridges are similar to features on Earth called yardangs, which are formed by intense winds plucking individual grains from, and by wind-driven sand blasting particles off, sedimentary deposits.

    The image was taken on October 30, 1997 at 11:05 AM PST, shortly after the Mars Global Surveyor spacecraft's 31st closest approach to Mars. The image covers an area 3.6 X 21.5 km (2.2 X 13.4 miles) at 3.6 m (12 feet) per picture element--craters only 11 m (36 feet, about the size of a swimming pool) across can be seen. The best Viking view of the area (VO 1 387S34) has a resolution of 240 m/pixel, or 67 times lower resolution than the MOC frame.

    Malin Space Science Systems (MSSS) and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

  16. The Age of the Medusae Fossae Formation

    NASA Astrophysics Data System (ADS)

    Kerber, L.; Head, J. W.

    2008-09-01

    Introduction The Medusae Fossae Formation (MFF) is a complicated and discontinuous formation located in the southern parts of Elysium Planitia and Amazonis Planitia (130°-230°E and 12°S-12°N), covering an area of approximately 2.1 x 106 km2 and having an estimated volume of 1.4 x 106 km3 [1]. It is thought to have been deposited during the Amazonian period [2,3]. However, much of the cratering record may have been erased as friable units were eroded and long-buried terrains exhumed [4-6]. The formation is characterized by large accumulations of fine-grained, friable deposits and evidence of large amounts of erosion. There are many theories regarding the emplacement of this formation; recently the literature has focused on three possibilities: ignimbrites, ash fall, and aeolian dust. Some modified and inverted fluvial channels have been found within the deposit [7,8], (Fig. 1), indicating that there was some fluvial activity during or after the emplacement of the MFF. If the MFF is among the youngest surficial deposits on Mars [9], it is implied that meandering, channelized flow must have extended into the Amazonian, a significant constraint when considering the atmospheric evolution of the planet through time. Because of the wide implications that these findings have for the evolution of Mars and the Martian atmosphere, it is instructive to re-examine the evidence for the Amazonian age of the MFF. The initial conclusion comes from two main arguments: the relatively few superposed craters on the unit, and the superposition of the MFF on young lowland lava deposits [1, 9]. Using new high resolution data, we reexamine the relationships both within the MFF and with respect to adjacent units. Cratering Record The cratering record of the MFF and other easily eroded units has often been deemed unreliable [4, 10, 12], but it continues to be cited as evidence for the formation's young age. Throughout the MFF, pedestal craters, inverted craters, and remnant knobs can be

  17. Pulmonary Alveolar Microlithiasis “Stone Lungs”: A Case of Clinico-Radiological Dissociation

    PubMed Central

    Shaharyar, Sameer; Chokshi, Binna; Bhardwaj, Nikhil

    2016-01-01

    Pulmonary alveolar microlithiasis (PAM) is a rare infiltrative lung disease characterized by deposition of spherical calcium phosphate microliths called calcospherites within the alveoli. PAM was first described by Friedrich in 1856 and then by Harbitz in 1918. The disease pathogenesis is based on mutations in the SLC34A2 gene that encodes for the Type IIb sodium-phosphate cotransporter. The majority of the patients are diagnosed at an early age, usually between the ages of 20 and 40 years. The hallmark of this disease is a striking dissociation between the radiological findings and the mild clinical symptoms.  We report a case of 35-year-old woman who presented post-motor vehicle accident with back pain and with minimal dyspnea on exertion. The final diagnosis was made after computed tomography and lung biopsy. The present case exhibits the remarkable clinico-radiological dissociation with complete calcification of the lungs on radiographic images with a relatively mild clinical presentation. PMID:27688986

  18. Extra-axial ependymoma of posterior fossa extending to the Meckel's cave.

    PubMed

    Torun, Fuat; Tuna, Hakan; Bozkurt, Melih; Deda, Haluk

    2005-06-01

    An extra-axial ependymoma extending from the left cerebellopontine corner to the Meckel's cave is reported. This lesion's clinical, radiological, and histological characteristics are presented. This tumor's infrequent extra-axial location, extension to the Meckel's cave and possible origin are discussed.

  19. Fossa navicularis magna detection on cone-beam computed tomography

    PubMed Central

    Mupparapu, Mel

    2016-01-01

    Herein, we report and discuss the detection of fossa navicularis magna, a close radiographic anatomic variant of canalis basilaris medianus of the basiocciput, as an incidental finding in cone-beam computed tomography (CBCT) imaging. The CBCT data of the patients in question were referred for the evaluation of implant sites and to rule out pathology in the maxilla and mandible. CBCT analysis showed osseous, notch-like defects on the inferior aspect of the clivus in all four cases. The appearance of fossa navicularis magna varied among the cases. In some, it was completely within the basiocciput and mimicked a small rounded, corticated, lytic defect, whereas it appeared as a notch in others. Fossa navicularis magna is an anatomical variant that occurs on the inferior aspect of the clivus. The pertinent literature on the anatomical variations occurring in this region was reviewed. PMID:27051639

  20. Ganglion cyst in the supraspinous fossa: arthroscopically undetectable cases.

    PubMed

    Shimokobe, Hisao; Gotoh, Masafumi; Mitsui, Yasuhiro; Yoshikawa, Eiichiro; Kume, Shinichiro; Okawa, Takahiro; Higuchi, Fujio; Nagata, Kensei; Shiba, Naoto

    2013-01-01

    Studies have demonstrated favorable outcomes of arthroscopic decompression for ganglion cyst in the supraspinous fossa; however, little attention has been paid to the difficulty in detecting these cysts during arthroscopy. In this report, we present 2 cases in which ganglion cysts in the supraspinous fossa were undetectable during arthroscopy. The ganglion cysts were not identified in these cases during surgery despite arthroscopic decompression being performed through the area in which the cyst was expected until the suprascapular nerve was entirely exposed. After surgery, magnetic resonance imaging (MRI) confirmed the disappearance of the ganglion cyst and external rotation strength was fully improved, without shoulder pain. We emphasize here that surgeons should be aware of this difficulty when performing arthroscopic decompression of ganglion cysts in the supraspinous fossa.

  1. Pulmonary sporotrichosis: case series and systematic analysis of literature on clinico-radiological patterns and management outcomes.

    PubMed

    Aung, Ar Kar; Teh, Bing Mei; McGrath, Christopher; Thompson, Philip J

    2013-07-01

    Pulmonary infections by Sporothrix spp. manifest radiologically as cavitary or non-cavitary disease depending on whether the infection is primary pulmonary or multifocal sporotrichosis. Despite current guidelines, the optimal management for pulmonary sporotrichosis remains unclear. In order to clarify this, we present two cases of pulmonary sporotrichosis, as well as the results of a comprehensive literature review of treatment outcomes based on clinico-radiological presentation patterns of the disease. A literature search of all case reports in English language over the last 50 years (1960-2010) was conducted. Data on patient characteristics, risk factors, clinico-radiological patterns, treatment modalities and outcomes were collected and analyzed. A total of 86 cases were identified, i.e., 64 (74.4%) primary pulmonary and 22 (25.6%) multifocal sporotrichosis. Radiologically, primary pulmonary disease was commonly characterized by cavity formation which was lacking in multifocal infections (P = 0.0001). Immunosuppressant use was more common in multifocal sporotrichosis (P = 0.0001), while hemoptysis was more common in primary pulmonary form (P = 0.01). No other differences in patient characteristics or risk factors were noted. Extra-pulmonary multifocal sporotrichosis most commonly involved skin (81.8%) and joints (45.4%). For patients with cavitary primary pulmonary sporotrichosis, outcomes from medical therapy alone were inferior to surgical intervention (P = 0.02). However, for both primary pulmonary and multifocal sporotrichosis with non-cavitary disease, medical therapy alone provided good outcomes. Only 12 (16.7%) cases were treated with itraconazole. Treatment of pulmonary sporotrichosis should be guided by the clinico-radiological patterns of presentation. Medical therapy alone is likely sufficient for non-cavitary disease while early surgery should be considered for cavitary primary pulmonary sporotrichosis. The experience in treating cavitary disease

  2. Discovery of Olivine in the Nili Fossae Region of Mars

    USGS Publications Warehouse

    Hoefen, T.M.; Clark, R.N.; Bandfield, J.L.; Smith, M.D.; Pearl, J.C.; Christensen, P.R.

    2003-01-01

    We have detected a 30,000-square-kilometer area rich in olivine in the Nili Fossae region of Mars. Nili Fossae has been interpreted as a complex of grabens and fractures related to the formation of the Isidis impact basin. We propose that post-impact faulting of this area has exposed subsurface layers rich in olivine. Linear mixture analysis of Thermal Emission Spectrometer spectra shows surface exposures of 30% olivine, where the composition of the olivine ranges from Fo30 to Fo70.

  3. Endoscopic Removal of a Bullet in Rosenmuller Fossa: Case Report

    PubMed Central

    Burks, Joshua D.; Glenn, Chad A.; Conner, Andrew K.; Bonney, Phillip A.; Sanclement, Jose A.; Sughrue, Michael E.

    2016-01-01

    Fractures of the anterior skull base may occur in gunshot victims and can result in traumatic cerebrospinal fluid (CSF) leak. Less commonly, CSF leaks occur days or even weeks after the trauma occurred. Here, we present the case of a 21-year-old man with a delayed-onset, traumatic CSF leak secondary to a missile injury that left a bullet fragment in the Rosenmuller fossa. The patient was treated successfully with endoscopic, endonasal extraction of the bullet, and repair with a nasal septal flap. Foreign bodies lodged in Rosenmuller fossa can be successfully treated with endoscopic skull base surgery. PMID:27330924

  4. Mesenteric panniculitis: prevalence, clinicoradiological presentation and 5-year follow-up

    PubMed Central

    van Bommel, E F H; Elgersma, O E; Hendriksz, T R

    2014-01-01

    Objective: To determine prevalence, clinicoradiological characteristics and outcome of patients with mesenteric panniculitis (MP) in a large hospital-based population. Methods: Consecutive abdominal CT examinations of 3820 patients were evaluated for MP. Clinical characteristics, therapy and outcome of patients with MP were evaluated during a 5-year follow-up period. A matched pair analysis was performed to further investigate the relation between MP and malignancy. Results: 94 (2.5%) patients with MP were identified (mean age, 66.6 ± 11.2 years, 70.2% male). MP coexisted with malignancy (especially prostatic carcinoma) in 48.9% of patients, and this was slightly but significantly higher than in age- and sex-matched control patients (n = 188, 46.3%). In 48 patients, MP was presumed to be idiopathic. The most frequent presenting symptom was pain (54.3%). Laboratory findings revealed increased acute-phase reactants in half of the patients with MP. CT findings included increased density of mesenterial fat (mean, −56.8 ± 10.8 HU), fat ring sign, tumoural pseudocapsule and small soft-tissue nodules. Patients with MP (14.6%) developed significantly more malignancies during a 5-year follow-up than did the control group (6.9%). One patient was treated with prednisone without satisfactory response. Conclusion: The prevalence of MP in this study was 2.5%. In most patients, radiologic features included increased mesenteric fat density, fat ring sign and small soft-tissue nodules. MP was associated with a significant higher prevalence of coexisting malignancies and a higher prevalence of future cancer development. Advances in knowledge: A more accurate prevalence of MP on CT is demonstrated. An underlying malignancy may play a role. PMID:25271412

  5. Clinicoradiological appraisal of ‘paraduodenal pancreatitis’: Pancreatitis outside the pancreas!

    PubMed Central

    Arora, Ankur; Rajesh, S; Mukund, Amar; Patidar, Yashwant; Thapar, Shalini; Arora, Asit; Bhatia, Vikram

    2015-01-01

    Purpose: Paraduodenal pancreatitis (PP) is a unique form of focal chronic pancreatitis that selectively involves the duodenum and aberrant pancreatic tissue located near the minor papilla (beyond the pancreas proper). The pseudotumoral nature of the disease often generates considerable clinical quandary and patient apprehension, and therefore merits a better understanding. The present study appraises the clinicoradiological manifestations of PP in 33 patients. Materials and Methods: Clinical, laboratory, and radiological manifestations of 33 patients of PP treated in gastroenterology/hepatology and hepato-pancreatico-biliary surgery units during June 2010-August 2014 were retrospectively reviewed. Results: All patients were young to middle-aged men (100%) with history of alcohol abuse (93.9%) and/or smoking (42.4%), who presented either with acute or gradually worsening abdominal pain (90.9%). Pancreatic enzymes and serum tumor markers remained normal or were mildly/transiently elevated. Cystic variant was detected in 57.6% (solid in 42.4%); the disease remained confined to the groove/duodenum (pure form) in 45.4%. Medial duodenal wall thickening with increased enhancement was seen in 87.87 and 81.81%, respectively, and duodenal/paraduodenal cysts were seen in 78.78%. Pancreatic calcifications and biliary stricture were seen 27.3% patients. Peripancreatic arteries were neither infiltrated nor encased. Conclusion: PP has a discrete predilection for middle-aged men with history of longstanding alcohol abuse and/or smoking. Distinguishing imaging findings include thickening of the pancreatic side of duodenum exhibiting increased enhancement with intramural/paraduodenal cysts. This may be accompanied by plate-like scar tissue in the groove region, which may simulate groove pancreatic carcinoma. However, as opposed to carcinoma, the peripancreatic arteries are neither infiltrated nor encased, rather are medially displaced. PMID:26288527

  6. A Comparison between splenic fossa and subhepatic fossa auxiliary partial heterotopic liver transplantation in a porcine model

    PubMed Central

    Liang, Xiao; Wang, Zhifei; Shen, Jie; Yu, Feiyan; Xie, Limei; Pan, Yongming; Lin, Hui

    2016-01-01

    To test the alternative possible locations for the placement of a liver graft and the relevant surgical technique issues, we developed a porcine model of auxiliary partial heterotopic liver transplantation (APHLT) and evaluated the difference between 2 styles of liver transplantation, either subhepatic fossa or splenic fossa APHLT, by comparing survival and biochemical indexes. Thirty‐eight miniature pigs were randomly divided into 2 groups. A left hemihepatic graft without the middle hepatic vein (HV) was procured from the living donor. In group A (n = 9), an 8 mm diameter polytetrafluoroethylene (PTFE) graft approximately 2.5 cm long was connected to the left HV while another PTFE graft of the same size was connected to the left portal vein (PV). The liver graft was implanted in the right subhepatic fossa following splenectomy and right nephrectomy. In group B (n = 10), a PTFE graft of the same size was connected to the left HV while the liver graft was implanted in the splenic fossa following splenectomy and left nephrectomy. Survival rate and complications were observed at 2 weeks after transplantation. Data were collected from 5 animals in group A and 6 animals in group B that survived longer than 2 weeks. The liver function and renal function of the recipients returned to normal at 1 week after surgery in both groups. Eighty‐eight percent (14/16) of the PTFE grafts remained patent at 2 weeks after surgery, but 44% of the PTFE grafts (7/16) developed mural thrombus. No significant differences in the survival rate and biochemistry were found between the 2 groups. In conclusion, the splenic fossa APHLT can achieve beneficial outcomes similar to the subhepatic fossa APHLT in miniature pigs, although it also has a high morbidity rate due to hepatic artery thrombosis, PV thrombosis, and PTEF graft mural thrombus formation. Liver Transplantation 22 812–821 2016 AASLD. PMID:26785299

  7. Fretted Terrain Valley in Coloe Fossae Region

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] Figure 1 Click on image for larger version

    The image in figure 1 shows lineated valley fill in one of a series of enclosed, intersecting troughs known as Coloe (Choloe) Fossae. Lineated valley fill consists of rows of material in valley centers that are parallel to the valley walls. It is probably made of ice-rich material and boulders that are left behind when the ice-rich material sublimates. Very distinct rows can be seen near the south (bottom) wall of the valley. Lineated valley fill is thought to result from mass wasting (downslope movement) of ice-rich material from valley walls towards their centers. It is commonly found in valleys near the crustal dichotomy that separates the two hemispheres of Mars. The valley shown here joins four other valleys with lineated fill near the top left corner of this image. Their juncture is a topographic low, suggesting that the lineated valley fill from the different valleys may be flowing or creeping towards the low area (movement towards the upper left of the image). The valley walls appear smooth at first glance but are seen to be speckled with small craters several meters in diameter at HiRISE resolution (see contrast-enhanced subimage). This indicates that at least some of the wall material has been stable to mass wasting for some period of time. Also seen on the valley wall are elongated features shaped like teardrops. These are most likely slightly older craters that have been degraded due to potentially recent downhill creep. It is unknown whether the valley walls are shedding material today. The subimage is approximately 140 x 400 m (450 x 1280 ft).

    Image PSP_001372_2160 was taken by the High Resolution Imaging Science Experiment (HiRISE) camera onboard the Mars Reconnaissance Orbiter spacecraft on November 11, 2006. The complete image is centered at 35.5 degrees latitude, 56.8 degrees East longitude. The range to the target site was 290.3 km (181

  8. Polymorphous low-grade adenocarcinoma of the nasal fossa.

    PubMed

    González-Lagunas, Javier; Alasà-Caparrós, Cristian; Vendrell-Escofet, Gerard; Huguet-Redecilla, Pere; Raspall-Martin, Guillermo

    2005-01-01

    An unusual case of a T4N2CMx polymorphous low grade adenocarcinoma located in the nasal fossae and extending to the pterygoid area is presented. The primary tumor was excised through a Lefort I maxillotomy and the neck was managed with a supraomohyoid neck dissection. Adjuntive postoperative radiotherapy was also administered to the patient.

  9. 21 CFR 872.3950 - Glenoid fossa prosthesis.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Glenoid fossa prosthesis. 872.3950 Section 872.3950 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... or a notice of completion of a PDP is required to be filed with the Food and Drug Administration...

  10. [Fracture of the glenoid fossa without mandibular condylar dislocation or fracture: two case reports].

    PubMed

    Şahan, Murat; Derin, Serhan; Beydilli, Halil; Çullu, Neşet

    2014-01-01

    The mandibular condyle region which protects the middle cranial fossa from facial and jaw traumas has an excellent osteomuscular structure. Condylar structures reduce or limit the force of trauma. Most importantly, the condylar neck is the weakest part of the mandible and is easily fractured without dislocation. Generally, this mechanism prevents condylar penetration into the middle cranial fossa; however, there are condylar penetration into the middle cranial fossa can be rarely. Glenoid fossa fractures without mandibular condylar fracture and dislocation can be made. In this article, we present two cases to assess the isolated glenoid fossa fractures of the temporal bone.

  11. Percutaneous Posterior Calcaneal Osteotomy.

    PubMed

    Lui, Tun Hing

    2015-01-01

    Different types of posterior calcaneal osteotomy are used for calcaneal realignment in the management of hindfoot deformity. We describe a percutaneous technique of posterior calcaneal osteotomy that can be either a Dwyer-type closing wedge osteotomy or displacement osteotomy.

  12. Posterior leukoencephalopathy syndrome as a cause of reversible blindness during pregnancy.

    PubMed

    Onderoglu, Lutfu S; Dursun, Polat; Gultekin, Murat; Celik, Nilufer Y

    2007-08-01

    Cortical blindness is a rare and dramatic complication of pre-eclampsia. The precise nature of the pathogenesis of this condition has not previously been understood. Three preeclamptic patients with unremarkable previous medical history presented with acute blindness between the 28th and 33rd weeks of pregnancy. They were all diagnosed as posterior leukoencephalopathy syndrome (PLES). In all these patients, MRI study revealed the typical feature of gray-white matter edema localized to the temporo-parieto-occipital areas. Vision and MRI findings were restored in all patients after delivery. Although PLES has been described as a puerperal clinicoradiologic entity, it may be seen in preeclamptic-eclamptic patients during the pregnancy. Therefore neuro-imaging studies should be carried out in pregnant patients with visual disturbances in order to exclude PLES. Prompt diagnosis, immediate control of blood pressure, and elimination of possible causes resolves clinical and imaging findings.

  13. Three-dimensional assessment of mandibular and glenoid fossa changes after bone-anchored Class III intermaxillary traction

    PubMed Central

    De Clerck, Hugo; Nguyen, Tung; de Paula, Leonardo Koerich; Cevidanes, Lucia

    2013-01-01

    Introduction Conventional treatment for young Class III patients involves extraoral devices designed to either protract the maxilla or restrain mandibular growth. The use of skeletal anchorage offers a promising alternative to obtain orthopedic results with fewer dental compensations. Our aim was to evaluate 3-dimensional changes in the mandibles and the glenoid fossae of Class III patients treated with bone-anchored maxillary protraction. Methods Twenty-five consecutive skeletal Class III patients between the ages of 9 and 13 years (mean age, 11.10 ± 1.1 year) were treated with Class III intermaxillary elastics and bilateral miniplates (2 in the infrazygomatic crests of the maxilla and 2 in the anterior mandible). The patients had cone-beam computed tomography images taken before initial loading and at the end of active treatment. Three-dimensional models were generated from these images, registered on the anterior cranial base, and analyzed by using color maps. Results Posterior displacement of the mandible at the end of treatment was observed in all subjects (posterior ramus: mean, 2.74 ± 1.36 mm; condyles: mean, 2.07 ± 1.16 mm; chin: mean, −0.13 ± 2.89 mm). Remodeling of the glenoid fossa at the anterior eminence (mean, 1.38 ± 1.03 mm) and bone resorption at the posterior wall (mean, −1.34 ± 0.6 mm) were observed in most patients. Conclusions This new treatment approach offers a promising alternative to restrain mandibular growth for Class III patients with a component of mandibular prognathism or to compensate for maxillary deficiency in patients with hypoplasia of the midface. Future studies with long-term follow-up and comparisons with facemask and chincup therapies are needed to better understand the treatment effects. PMID:22748987

  14. Actinomyces infection causing acute right iliac fossa pain

    PubMed Central

    Govindarajah, Narendranath; Hameed, Waseem; Middleton, Simon; Booth, Michael

    2014-01-01

    This is a case of a 75-year-old man being admitted to the on-call surgical department with acute abdominal pain. On arrival he was clinically dehydrated and shocked with localised pain over McBurney's point and examination findings were suggestive of appendiceal or other colonic pathology. Full blood testing revealed a white cell count of 38×109/L and a C reactive protein (CRP) of 278 mg/L. A CT scan revealed a gallbladder empyema that extended into the right iliac fossa. This case highlights the potential for a hyperdistended gallbladder empyema to present as acute right iliac fossa pain with blood tests suggestive of complicated disease. Further analysis confirmed Actinomyces infection as the underlying aetiology prior to a laparoscopic subtotal cholecystectomy. This case serves to remind clinicians of this as a rare potential cause of atypical gallbladder pathology. PMID:24872493

  15. Temporal fossa bone grafts: a new technique in craniofacial surgery.

    PubMed

    Spear, S L; Wiegering, C E

    1987-04-01

    The calvarium has become an increasingly popular bone-graft donor site. Previously described harvesting techniques are often difficult to perform and may produce unsatisfactory bone fragments. However, full-thickness bone grafts taken from the region of the temporal fossa, beneath the temporaiis muscle, have proven to be of high quality and technically easy to obtain. In our experience with eight patients, temporal fossa bone grafts were used primarily around the orbit, including reconstruction of the orbital floor, frontal bone, and zygoma. The procedure begins with a hemicoronal or bicoronal incision; the temporalis muscle is reflected, and an underlying bone plate up to 4 X 6 cm is removed. The resulting bone graft is consistently 3 to 4 mm in thickness. The cranial defect is packed with bone debris, and the muscle is replaced. This technique has proven to be safe, technically simple, consistently productive of high-quality bone grafts, and within discernible donor-site deformity.

  16. Encephalomyelitis by Toxoplasma gondii in a captive fossa (Cryptoprocta ferox).

    PubMed

    Corpa, J M; García-Quirós, A; Casares, M; Gerique, A C; Carbonell, M D; Gómez-Muñoz, M T; Uzal, F A; Ortega, J

    2013-03-31

    Encephalomyelitis due to Toxoplasma gondii was diagnosed in a fossa (Cryptoprocta ferox). The animal had ataxia, atrophy of hind limb muscles and progressive wasting before dying 12 months after the onset of clinical signs. Toxoplasmosis was suspected antemortem based on clinical signs and the detection of T. gondii DNA by PCR on EDTA-blood from live animal. Necropsy revealed necrotizing gastritis and severe emaciation. The main histological lesions included non-suppurative encephalomyelitis, with dilation of myelin sheaths and swollen axons in the spinal cord, and multifocal gliosis in the brain with intralesional protozoan cysts that stained positive for T. gondii immunohistochemistry. To the authors' knowledge, this is the first report of toxoplasmosis in a fossa, and a new host record.

  17. Extradural Dermoid Cyst of the Anterior Infratemporal Fossa. Case Report

    PubMed Central

    Watanabe, Kentaro; Filomena, Carol A.; Nonaka, Yoichi; Matsuda, Masahide; Zomorodi, Ali R.; Friedman, Allan H.; Fukushima, Takanori

    2015-01-01

    Dermoid cysts are rare in the skull base. There have been 10 reported cases of dermoid cysts in the cavernous sinus, two in the petrous apex, and one in the extradural Meckel cave. This is the first case report of a dermoid cyst in the anterior infratemporal fossa attached to the anterior dura of the foramen ovale. The clinical presentation, radiologic findings, histologic features, tumor origin, and operative technique are described along with a review of the literature. PMID:26623226

  18. Morphology of the caudal fossa in Cavalier King Charles Spaniels.

    PubMed

    Cerda-Gonzalez, Sofia; Olby, Natasha J; McCullough, Susan; Pease, Anthony P; Broadstone, Richard; Osborne, Jason A

    2009-01-01

    Chiari malformations and syringohydromyelia are an important disease complex in Cavalier King Charles Spaniels. Although abnormalities in caudal fossa morphology are considered major contributors to the development of this disease, limited information exists on the range of morphologies in Cavalier King Charles Spaniels and on the relationship of these to clinically evident disease. Sixty-four Cavalier King Charles Spaniels were studied. Each underwent a neurologic examination and magnetic resonance imaging of the cervical spine and brain. T2-weighted sagittal images were used to determine both the morphologic characteristics and volume of the caudal fossa in each dog. This volume was also analyzed as a percentage of total cranial cavity volume. Each attribute was correlated with neurological grade and presence of syringohydromyelia. Fifteen dogs had neurologic signs, and 59 had morphologic abnormalities of the craniocervical junction. While 27 dogs had syringohydromyelia, 13 of these were clinically normal. Cerebellar herniation and occipital dysplasia were common findings but were not associated with syringohydromyelia. Dorsal compressive lesions were noted at the first and second cervical vertebral junction. Factors associated with the presence of neurologic signs included syringohydromyelia and the ratio of caudal fossa/total cranial cavity volume; dogs with signs had significantly larger syringohydromyelia than asymptomatic dogs. Caudal fossa size was not associated with syringohydromyelia. A positive association was identified between foramen magnum size and length of cerebellar herniation. The prevalence of craniocervical junction abnormalities is high in Cavalier King Charles Spaniels. While several factors are associated with neurologic signs, occipital hypoplasia appears to be the most important factor.

  19. Middle fossa approach: Applications in temporal bone lesions.

    PubMed

    Domenech Juan, Iván; Cruz Toro, Paula; Callejo Castillo, Ángela; Moya, Rafael; Merán Gil, Jorge L; Bartel, Ricardo

    2016-01-01

    The middle fossa approach is a surgical technique that is very useful for lateral skull base surgery. However, it is true that it has limited surgical indications and implementation due to its technical complexity. We present our experience in 10 patients in whom the middle fossa approach was the treatment of choice because of the extent of the injury and complexity of the lesion or process. Despite the complexity of the cases, there was no mortality associated with surgery. Postoperative complications were found in 2 patients who presented an epidural hematoma and a cortico-subcortical hematoma. Hearing function was preserved in 5 patients out of the 7 who had adequate hearing at the time of surgery. House/Brackmann I-II facial nerve function was achieved in 8 patients; the remaining 2 had no deterioration of the nerve function. In 9 out of 10 patients, the surgery achieved complete solution of the lesion. The middle fossa approach is a safe and reliable surgical technique. It gives us great control and exposure of different skull base processes. We consider its knowledge of great importance, because it may be the only viable surgical alternative in some specific patients. That is the reason why it is important to learn this approach and know about it in our specialty.

  20. Reduced modulation of scanpaths in response to task demands in posterior cortical atrophy.

    PubMed

    Shakespeare, Timothy J; Pertzov, Yoni; Yong, Keir X X; Nicholas, Jennifer; Crutch, Sebastian J

    2015-02-01

    A difficulty in perceiving visual scenes is one of the most striking impairments experienced by patients with the clinico-radiological syndrome posterior cortical atrophy (PCA). However whilst a number of studies have investigated perception of relatively simple experimental stimuli in these individuals, little is known about multiple object and complex scene perception and the role of eye movements in posterior cortical atrophy. We embrace the distinction between high-level (top-down) and low-level (bottom-up) influences upon scanning eye movements when looking at scenes. This distinction was inspired by Yarbus (1967), who demonstrated how the location of our fixations is affected by task instructions and not only the stimulus' low level properties. We therefore examined how scanning patterns are influenced by task instructions and low-level visual properties in 7 patients with posterior cortical atrophy, 8 patients with typical Alzheimer's disease, and 19 healthy age-matched controls. Each participant viewed 10 scenes under four task conditions (encoding, recognition, search and description) whilst eye movements were recorded. The results reveal significant differences between groups in the impact of test instructions upon scanpaths. Across tasks without a search component, posterior cortical atrophy patients were significantly less consistent than typical Alzheimer's disease patients and controls in where they were looking. By contrast, when comparing search and non-search tasks, it was controls who exhibited lowest between-task similarity ratings, suggesting they were better able than posterior cortical atrophy or typical Alzheimer's disease patients to respond appropriately to high-level needs by looking at task-relevant regions of a scene. Posterior cortical atrophy patients had a significant tendency to fixate upon more low-level salient parts of the scenes than controls irrespective of the viewing task. The study provides a detailed characterisation of

  1. Posterior foss avenous angiomas with drainage through the brain stem

    SciTech Connect

    Damiano, T.R.; Truwit, C.L. ); Dowd, C.F. ); Symonds, D.L. )

    1994-04-01

    To describe 11 cases of posterior fossa venous angiomas with drainage through the brain stem. Eleven cases of posterior fossa venous angioma with drainage through the brain stem were evaluated using MR. Correlation with known routes of venous drainage for the cerebellum and brain stem is made. Six of the 11 venous angiomas were found in the cerebellum, four in the brain stem; one involved both the cerebellum and brain stem. The cerebellar venous angiomas drained to subependymal veins about the fourth ventricle and dorsal pons. These then connected with an enlarged transmesencephalic or transpontine vein, to drain anteriorly to the anterior pontine veins. The brain stem angiomas had variable drainage depending on location. Evidence of hemorrhage was seen in five cases. Cerebellar and brain stem venous angiomas have several potential routes of drainage, including an enlarged vein traversing the pons, midbrain, or medulla. A knowledge of the normal venous anatomy of this region helps to understand the occurrence of these uncommon routes of venous drainage. 15 refs., 8 figs., 1 tab.

  2. Xanthomatous posterior pyramid meningioma in a 2-year-old girl.

    PubMed

    Germanò, A; Galatioto, S; La Rosa, G; Caffo, M; Cardia, E

    1997-07-01

    Meningiomas are common lesions in adults but unusual in infancy and meningiomas located in the posterior cranial fossa are even more rare. Metaplastic changes of meningothelial meningiomas can lead to the rarely observed xanthomatous form. We describe the case of a posterior pyramid xanthomatous meningioma in a 2-year-old girl. After detailed neuroradiological evaluation, the histological diagnosis was confirmed with the aid of immunohistochemical evaluation. A critical case evaluation in the light of the more recent literature, the surgical strategy and technique, and an immunohistological hypothesis are reported.

  3. Bilateral submandibular gland aplasia with clinico-radiological mass due to prolapsing sublingual salivary tissue through mylohyoid boutonniere: a case report and review.

    PubMed

    Ahmed, M; Strauss, M; Kassaie, A; Shotelersuk, V; DeGuzman, R

    2009-02-01

    Aplasia of major salivary glands is very rare. Compensatory hypertrophy of the rest of the glands can result in clinico-radiological masses. We present a report of a rare case of non-syndromic bilateral submandibular gland aplasia with hypertrophied sublingual salivary tissue, the latter herniating through mylohyoid boutonnière to present as a palpable mass on the left side with corresponding CT findings. Multiplanar evaluation is emphasised by utilizing multidetector CT.

  4. Posterior reversible encephalopathy syndrome--Insight into pathogenesis, clinical variants and treatment approaches.

    PubMed

    Granata, Guido; Greco, Antonio; Iannella, Giannicola; Granata, Massimo; Manno, Alessandra; Savastano, Ersilia; Magliulo, Giuseppe

    2015-09-01

    Posterior reversible encephalopathy syndrome is a rare clinicoradiological entity characterized by typical MRI findings located in the occipital and parietal lobes, caused by subcortical vasogenic edema. It was first described as a distinctive syndrome by Hinchey in 1996. Etiopathogenesis is not clear, although it is known that it is an endotheliopathy of the posterior cerebral vasculature leading to failed cerebral autoregulation, posterior edema and encephalopathy. A possible pathological activation of the immune system has been recently hypothesized in its pathogenesis. At clinical onset, the most common manifestations are seizures, headache and visual changes. Besides, tinnitus and acute vertigo have been frequently reported. Symptoms can be reversible but cerebral hemorrhage or ischemia may occur. Diagnosis is based on magnetic resonance imaging, in the presence of acute development of clinical neurologic symptoms and signs and arterial hypertension and/or toxic associated conditions with possible endotheliotoxic effects. Mainstay on the treatment is removal of the underlying cause. Further investigation and developments in endothelial cell function and in neuroimaging of cerebral blood flow are needed and will help to increase our understanding of pathophysiology, possibly suggesting novel therapies.

  5. Hesperian age for western Medusae Fossae Formation, Mars.

    PubMed

    Zimbelman, James R; Scheidt, Stephen P

    2012-06-29

    The Medusae Fossae Formation (MFF) on Mars is an intensely eroded deposit north of the cratered highlands. It is widely thought that MFF materials were emplaced through ignimbrite eruptions. Recent geologic mapping of western MFF identified outliers of MFF materials well beyond the previously mapped western extent for the deposit, including outliers close to Gale crater. We report counts of impact craters on the MFF units that have implications for our understanding of the general history of MFF and the uppermost layered materials on the Gale crater mound.

  6. Chondroblastoma of the temporal bone: consistent middle fossa involvement.

    PubMed

    Selesnick, S H; Levine, J M

    1999-01-01

    The objective of this study is to describe the presentation and clinical course of two patients with temporal bone chondroblastoma, and to review the literature on temporal bone chondroblastoma to identify characteristic clinical and radiological presentations, and optimal treatment regimens. MEDLINE literature searches covering the period from 1966 to January 1998, in all languages, were performed as well as a review of the bibliographies of the identified studies. Strict inclusion criteria were upheld, In total 18 studies had patients whose data could be analyzed. From the 18 studies, 34 patients were identified, but only 21 cases met the inclusion criteria. Demographic, clinical presentation, radiological, operative and treatment parameters were analyzed in this cohort of patients. Ninety-five percent of patients were found to have invasion of the middle cranial fossa and 76% were found to have erosion into the superior aspect of the external auditory canal by temporal bone chondroblastoma. The characteristic growth pattern of temporal bone chondroblastoma may result from embryonal or cartilagenous rests entrapped in the tympanosquamous suture line in the middle fossa floor. Temporal bone chondroblastoma represents a pathology that does not arise from, or have a growth pattern resembling other pathologies in the temporal bone.

  7. Incidence of Clavicular Rhomboid Fossa in Northeastern Thais: An Anthropological Study

    PubMed Central

    Sampannang, Apichakan; Tuamsuk, Panya; Kanpittaya, Jaturat

    2016-01-01

    The rhomboid fossa of clavicle is used to determine the age and sex in anthropology and forensic sciences. The variant types of rhomboid fossa on inferior surface have been reported in many races except in Thais. This study therefore was aimed at classifying the types of the rhomboid fossa in Northeastern Thais. The identified 476 Northeastern Thais dried clavicles (270 males and 206 females) were observed and recorded for the types of rhomboid fossa. The results showed that Thai-rhomboid fossa could be classified into 4 types: Type 1: smooth; Type 2: flat; Type 3: elevated; and Type 4: depressed, respectively. The incidences of rhomboid fossa were as follows: Type 1: 0.21%; Type 2: 19.75%; Type 3: 76.26%; and Type 4: 3.78%, respectively. Additionally, it was found that the percentage of Type 4 (11.84%) was much greater than that of female (1.94%) compared to other types. This incidence of rhomboid fossa types especially Type 4 may be a basic knowledge to be used in sex identification. The high incidence of rhomboid fossa in both sexes of Northeastern Thai clavicles was Type 3 (elevated type). PMID:27648305

  8. Reconciling the convergence of supraspinous fossa shape among hominoids in light of locomotor differences.

    PubMed

    Green, David J; Sugiura, Yui; Seitelman, Brielle C; Gunz, Philipp

    2015-04-01

    Differences in scapular morphology between modern humans and the African and lesser apes are associated with the distinct locomotor habits of these groups. However, several traits, particularly aspects of the supraspinous fossa, are convergent between Homo and Pongo-an unexpected result given their divergent locomotor habits. Many morphological assessments of the scapula rely on the limited number of static landmarks available, and traditional approaches like these tend to oversimplify scapular shape. Here, we present the results of two geometric morphometric (GM) analyses of hominoid supraspinous fossa shape-one employing five homologous landmarks and another with 83 sliding semilandmarks-alongside those of traditional methods to evaluate if three-dimensional considerations of fossa shape afford more comprehensive insights into scapular shape and functional morphology. Traditional measures aligned Pongo and Homo with narrow and transversely oriented supraspinous fossae, whereas African ape and Hylobates fossae are broader and more obliquely situated. However, our GM results highlight that much of the convergence between Homo and Pongo is reflective of their more medially positioned superior angles. These approaches offered a more complete assessment of supraspinous shape and revealed that the Homo fossa, with an intermediate superior angle position and moderate superoinferior expansion, is actually reminiscent of the African ape shape. Additionally, both Pongo and Hylobates were shown to have more compressed fossae, something that has not previously been identified through traditional analyses. Thus, the total morphological pattern of the Pongo supraspinous fossa is unique among hominoids, and possibly indicative of its distinctive locomotor habits.

  9. Posterior Cruciate Ligament Injury

    MedlinePlus

    ... ACL connect your thighbone (femur) to your shinbone (tibia). If either ligament is torn, it might cause ... ligaments connect the thighbone (femur) to the shinbone (tibia). The anterior and posterior cruciate ligaments form an " ...

  10. Posterior ankle impingement syndrome.

    PubMed

    Maquirriain, Javier

    2005-10-01

    Posterior ankle impingement syndrome is a clinical disorder characterized by posterior ankle pain that occurs in forced plantar flexion. The pain may be acute as a result of trauma or chronic from repetitive stress. Pathology of the os trigonum-talar process is the most common cause of this syndrome, but it also may result from flexor hallucis longus tenosynovitis, ankle osteochondritis, subtalar joint disease, and fracture. Patients usually report chronic or recurrent posterior ankle pain caused or exacerbated by forced plantar flexion or push-off maneuvers, such as may occur during dancing, kicking, or downhill running. Diagnosis of posterior ankle impingement syndrome is based primarily on clinical history and physical examination. Radiography, scintigraphy, computed tomography, and magnetic resonance imaging depict associated bone and soft-tissue abnormalities. Symptoms typically improve with nonsurgical management, but surgery may be required in refractory cases.

  11. Piriform and trochanteric fossae. A drawing mismatch or a terminology error? A review.

    PubMed

    Papadakis, Stamatios A; Shepherd, Lane; Babourda, Eleni C; Papadakis, Stefanos

    2005-08-01

    The current literature indicates that the standard starting point for intramedullary nailing is the piriform fossa. The accuracy of the entry point for anterograde femoral intramedullary nailing between published texts and relevant illustrations was recorded. The piriform fossa is the site of insertion of the piriform tendon and represents a small, shallow depression located on the tip of the greater trochanter. The trochanteric fossa is a deep depression on the inner surface of the greater trochanter, and in the vast majority of the published data is indicated incorrectly as "piriform fossa". As a result of either a recurrent drawing mismatch or a terminology error, the correct entry point for anterograde femoral intramedullary nailing is confusing and should be indicated in the current literature. The trochanteric fossa appears to be the standard entry point that most surgeons recommend.

  12. An evaluation of a resorbable (semirigid) GTR membrane in human periodontal intraosseous defects: A clinicoradiological re-entry study

    PubMed Central

    Gowda, Vinayak S.; Chava, Vijay; Kumara, Ajeya E. G.

    2011-01-01

    Aim: To evaluate the effectiveness of a resorbable, semi rigid guided tissue regeneration (GTR) membrane in the treatment of periodontal intraosseous defects. Settings and Design: Randomized controlled clinicoradiological re-entry study. Materials and Methods: Eight patients with bilateral, identical intraosseous defects were selected. The sides for test and control group were randomly allocated to treat either with bioresorbable semi rigid membrane (test group) or open flap debridement (control group). Radiographic analysis was done by comparing intraoral peri apical radiographs taken at baseline and at six months. Extended cone paralleling device with grid was used to standardize radiographs. Auto CAD software was used for the analysis. Statistical Analysis Used: Paired-t test. Results: On surgical reentry at six months, the mean reduction in depth of the defect at the test site was 2.63 mm. The mean gain in Relative attachment level was 1.75 mm. The control sites showed a statistically insignificant gain. The mean percentage defect fill assessed on radiographs using auto CAD software was 15.54%. Conclusion: The resorbable, semi-rigid GTR membrane can be effectively used for the treatment of human one-walled angular defects. PMID:22368366

  13. Posterior Reversible Encephalopathy Syndrome in Henoch-Schonlein Purpura and Hemolytic Uremic Syndrome

    PubMed Central

    Fidan, Kibriya; Kandur, Yasar; Ucar, Murat; Gucuyener, Kivilcim; Soylemezoglu, Oguz

    2016-01-01

    Posterior reversible encephalopathy syndrome (PRES) is a clinico-radiological syndrome, composed of symptoms such as headache, seizures, visual disturbances, lethargy, confusion, stupor, focal neurologic findings and radiological findings of bilateral gray and white matter abnormalities suggestive of edema in the posterior regions of the cerebral hemispheres. PRES is associated with significant morbidity and mortality if it is not expeditiously recognized. Magnetic resonance image (MRI) represents the most sensitive imaging technique for recognizing PRES. PRES has been seen in various clinical settings including renal disorders such as acute glomerulonephritis, lupus nephritis, nephrotic syndrome, and drug usage such as calcineurin inhibitors. We aimed to present two study cases for such clinical setting. In this report, we present two patients with PRES in whom the primary diagnosis was hemolytic uremic syndrome (HUS) and Henoch-Schonlein purpura (HSP). Both of them were treated with anticonvulsant and proper antihypertensive drugs. A repeated MRI scan of the head, an ophthalmologic assessment, and a follow-up electroencephalogram produced normal results with no sequelae. Early recognition of PRES as a complication during different diseases and therapies in childhood may facilitate the appropriate treatment, so that intensive treatment should be performed as soon as possible to avoid neurological sequelae. PMID:27298664

  14. Dimensions of the temporal glenoid fossa and tooth wear in prehistoric human skeletons.

    PubMed

    Owen, C P; Wilding, R J; Adams, L P

    1992-01-01

    Both the mandibular condyle and the glenoid fossa remodel in response to changes in the dentition during life, although the precise relationship between teeth and joint is not clear. This study was undertaken to ascertain changes, if any, occurring in the glenoid fossae in skeletons with much tooth wear. In a collection of skulls from an excavation site on the South African coast, occlusal wear was measured using the scale devised by Molnar. The dimensions of the glenoid fossae were measured using a reflex microscope. Profiles of the glenoid fossa at right angles to a line through its medial and lateral poles provided estimates of the slope of the articular eminence in three places: centrally, and midway between this slope and each of the poles. The mediolateral profile gave an estimate of the height and gabling of the fossa. Central and lateral slope angles showed weak correlation with molar wear, and the medial but not the lateral angel was significantly different from the central. The fossa appears to remodel in response to patterns of forces generated during function, but compared to the condyle, is not as strongly influenced. This may be accounted for if the relative load-bearing areas of the condyle and fossa are considered.

  15. Amyloidoma Involving the Orbit, Meckel's Cave and Infratemporal Fossa: 3T MRI Findings.

    PubMed

    Menetti, F; Bartolomei, I; Ambrosini-Spaltro, A; Salvi, F; Agati, R; Leonardi, M

    2009-03-23

    Amyloidoma is a rare lesion characterized by tissue deposition of an abnormal fibrillary protein (amyloid). It is the focal and localized counterpart of systemic amyloidosis, where the deposition of amyloid diffusely involves several organs. The few literature reports of intracranial amyloidomas include lesions involving the pituitary gland, orbit, cerebral hemispheres, temporal bone, cerebellopontine angle and jugular foramen. We describe the case of a 27-year-old woman presenting with painless slowly progressive proptosis of the right eye. The patient underwent a contrast-enhanced CT study of the head, followed by 3T MRI which disclosed a homogeneous mass in the right Meckel's cave and cavernous sinus, extending through an enlarged foramen ovale to the infratemporal fossa. The right optic nerve and ocular muscles were enlarged and infiltrated along with the retrobulbar fat by contrast-enhancing tissue. Thin contrast-enhanced MRI scans through the area of interest showed the mass to extend posterior to the gasserian ganglion, involving the cerebellopontine angle cistern, where the intracisternal parts of the III, V, and VI nerves bilaterally appeared enlarged and showed perineural enhancement. The lesion closely mimicked a malignant tumor with perineural tumor infiltration, so we performed fine needle biopsy of the portion of the lesion near the right foramen ovale under fluoroscopic guidance. Histopathology revealed that the lesion was an amyloidoma. Further clinical and blood examinations, serum chemistry, followed by biopsy of the periumbilical fat showed no signs of systemic amyloidosis or an underlying inflammatory or neoplastic disorder. No further treatment was instituted, follow-up MRI six months later showed no enlargement of the mass.

  16. The tibialis posterior tendon.

    PubMed

    Lhoste-Trouilloud, A

    2012-02-01

    The tibialis posterior tendon is the largest and anteriormost tendon in the medial ankle. It produces plantar flexion and supination of the ankle and stabilizes the plantar vault. Sonographic assessment of this tendon is done with high-frequency, linear-array transducers; an optimal examination requires transverse retromalleolar, longitudinal retromalleolar, and distal longitudinal scans, as well as dynamic studies. Disorders of the posterior tibial tendon include chronic tendinopathy with progressive rupture, tenosynovitis, acute rupture, dislocation and instability, enthesopathies. The most common lesion is a progressive "chewing gum" lesion that develops in a setting of chronic tendinopathy; it is usually seen in overweight women over 50 years of age with valgus flat feet. Medial ankle pain must also be carefully investigated, and the presence of instability assessed with dynamic maneuvers (forced inversion, or dorsiflexion) of the foot. Sonography plays an important role in the investigation of disorders involving the posterior tibial tendon.

  17. Posterior crossbites in children.

    PubMed

    Zhu, J F; Crevoisier, R; King, D L; Henry, R; Mills, C M

    1996-11-01

    Posterior crossbite, the most common malocclusion in young children, can be caused by a variety of skeletal, muscular, or dental factors. This condition produces insufficient maxillary arch width and is frequently associated with various oral sucking and postural habits. If left untreated, this problem can result in adverse skeletal growth changes. Various mechanical treatment modalities designed to expand the posterior maxillary arch width are available to correct this problem. The appropriate treatment method depends on the patient's age and level of cooperation as well as the determined etiology of the constriction.

  18. Wound breakdown after middle cranial fossa craniotomy: an unusual complication after rhytidectomy.

    PubMed

    Moberly, Aaron C; Tweel, Benjamin C; Welling, D Bradley

    2014-02-01

    Wound complications after middle cranial fossa craniotomy are rare. We describe a patient who underwent a left middle fossa craniotomy for resection of a small internal auditory canal tumor with subsequent development of wound breakdown and infection 1 week postoperatively. Prompting of the patient elicited a history of bilateral rhytidectomies. Wound debridement, hyperbaric oxygen therapy, dermal regeneration template placement, and prolonged antibiotic treatment were performed. Complete secondary intention healing occurred with an acceptable cosmetic outcome. Prior rhytidectomy scars must be identified and incorporated into the surgical planning prior to performing middle fossa craniotomy incisions.

  19. Tibialis Posterior Tendon Entrapment Within Posterior Malleolar Fracture Fragment.

    PubMed

    Fantry, Amanda; Lareau, Craig; Vopat, Bryan; Blankenhorn, Brad

    2016-01-01

    Management of posterior malleolus fractures continues to be controversial, with respect to both need for fixation and fixation methods. Fixation methods include an open posterior approach to the ankle as well as percutaneous reduction and fixation with or without arthroscopy for visualization of the articular surface. Plain radiographs are unreliable in identifying fracture pattern and intraoperative reduction, making arthroscopy a valuable adjunct to posterior malleolus fracture management. In this article, we report a case of tibialis posterior tendon entrapment within a posterior malleolus fracture, as identified by arthroscopy and managed with open reduction. Tibialis posterior tendon entrapment within a posterior malleolus has not been previously reported. Ankle arthroscopy for posterior malleolus fractures provides an opportunity to identify soft-tissue or tendinous entrapment, articular surface reduction, and articular cartilage injuries unlikely to be identified with fluoroscopy alone and should be considered in reduction and fixation of posterior malleolus fractures.

  20. Quantitative Analysis of Change in Intracranial Volume After Posterior Cranial Vault Distraction.

    PubMed

    Shimizu, Azusa; Komuro, Yuzo; Shimoji, Kazuaki; Miyajima, Masakazu; Arai, Hajime

    2016-07-01

    Posterior cranial vault distraction is considered to be more effective for increasing intracranial volume than fronto-orbital advancement or anterior cranial vault expansion, but the changes in intracranial volumes after posterior cranial vault distraction remain unclear. The changes in intracranial volume were investigated in patients of premature craniosynostosis treated by this technique. Seven patients, 3 boys and 4 girls aged from 5 months to 3 years 3 months (mean 23 months) at operation, with craniosynostosis underwent posterior cranial vault distraction at Juntendo University Hospital from 2011 to 2014. Patient characteristics, length of distraction, and pre- and postoperative computed tomography findings were reviewed. Total intracranial volume, including the supratentorial space and posterior cranial fossa, was measured using the workstation functions on three-dimensional computed tomography scans. Posterior distraction was performed without severe complications except in 2 patients requiring additional surgeries. The distraction length was 22.3 to 39 mm (mean 31 mm), the intracranial volume change was 144 to 281 mL (mean 192 mL), and the enlargement ratio of intracranial volume was 113% to 134% (mean 121%). The present quantitative analysis of intracranial volume change after posterior distraction showed greater increases in intracranial volume compared with previous reports. Furthermore, intracranial volumes in our patients became nearly normal and were maintained for the follow-up period (maximum 13 months). Posterior cranial vault distraction is very effective to increase cranial volume, so may be the first choice of treatment in patients of craniosynostosis.

  1. Rare and challenging extra-axial brain lesions: CT and MRI findings with clinico-radiological differential diagnosis and pathological correlation

    PubMed Central

    Demir, Mustafa Kemal; Yapıcıer, Özlem; Onat, Elif; Toktaş, Zafer Orkun; Akakın, Akın; Urgun, Kamran; Kılıç, Türker

    2014-01-01

    There are many kinds of extra-axial brain tumors and tumor-like lesions, and definitive diagnosis is complicated in some cases. In this pictorial essay, we present rare and challenging extra-axial brain lesions including neuroenteric cyst, primary leptomeningeal melanomatosis, isolated dural neurosarcoidosis, intradiploic epidermoid cyst, ruptured dermoid cyst, intraventricular cavernoma, and cavernous hemangioma of the skull with imaging findings and clinico-radiological differential diagnosis, including the pathologic correlation. Familiarity with these entities may improve diagnostic accuracy and patient management. PMID:25010368

  2. Nili Fossae in Natural Color and Across the Spectrum

    NASA Technical Reports Server (NTRS)

    2007-01-01

    The Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) took this image of the Nili Fossae region at 0643 UTC (2:43 a.m. EDT) on June 21, 2007, near 21.15 degrees north latitude, 74.24 degrees east longitude. CRISM's image was taken in 544 colors covering 0.36-3.92 micrometers, and shows features as small as 20 meters (66 feet) across. The region covered is just over 10 kilometers (6.2 miles) wide at its narrowest point, and is one of several dozen that CRISM has taken to map the minerals at candidate landing sites for the Mars Science Laboratory (MSL) mission, which will launch in 2010.

    The Nili Fossae region is critical to understanding the history of water on Mars and whether water ever formed environments suitable for life, because the region is underlain by a layer of phyllosilicate (clay) minerals. This type of mineralogy formed where water was in contact with Mars' crustal rocks for very long periods, altering the silicates in volcanic rocks. In addition, phyllosilicates can encapsulate and preserve organic chemicals associated with life (if life was present). Its rocky record of an ancient wet environment makes Nili Fossae a top contender among the 30-plus landing sites being considered for MSL, whose objectives include measuring the chemistry preserved in an ancient wet environment.

    This series of four different versions of the same 544-color image illustrates the mineral-mapping capability that comes from moving beyond the wavelength range of the human eye, and into infrared wavelengths where minerals leave distinct 'fingerprints' in reflected sunlight. At upper left, more than three dozen of the distinct wavelengths measured by CRISM were combined to mimic how the human eye would see the image. The subtle shading comes from the Sun's position high in Mars' sky when the image was taken, creating few shadows. The bland, butterscotch color comes from the dust coating nearly all of the Martian surface to some degree. At upper right

  3. Phyllosilicate and Olivine around a Fracture in Nili Fossae

    NASA Technical Reports Server (NTRS)

    2007-01-01

    The Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) took this observation of part of the Nili Fossae region at the western margin of the Isidis impact basin at 3:07 (UTC) on December 12, 2006, near 21.9 degrees north latitude, 78.2 degrees east longitude. The image was taken in 544 colors covering 0.36-3.92 micrometers, and shows features as small as 18 meters (60 feet) across. The image is about 11 kilometers (7 miles) wide at its narrowest point.

    The Isidis basin resulted from a gigantic impact on the surface of Mars early in the planet's history. The image of the Isidis basin at the top left is the colored elevation data from the Mars Orbiter Laser Altimeter (MOLA) overlain on a digital image mosaic from the Viking mission. Reds represent higher elevations, and blue lower elevations. The western rim of the Isidis basin has numerous, concentric troughs (or 'fossae') which may have formed during faulting associated with the impact event. Since then, the Nili Fossae region has since been heavily eroded, and is one of the most mineralogically diverse spots on Mars.

    This CRISM image targets one of region's smaller fractures. The image is shown overlain on the Viking digital image mosaic at lower left. The lower right CRISM image was constructed from three visible wavelengths (0.71, 0.60 and 0.53 microns in the red, green and blue image planes, respectively) and is close to what the human eye would see. The blue on the right of the image is an artifact from light scattering in the atmosphere. The upper right image was constructed from three infrared channels (2.38, 1.80 and 1.15 microns in the red, green and blue image planes, respectively) to highlight the mineralogy of the area. The bright green areas are rich in 'phyllosilicates,' a category of minerals including clays. The purple material along the walls of the fracture likely contains small amounts of the iron- and magnesium-rich mineral pyroxene. The yellow-brown material contains the

  4. Classification and clinicoradiologic features of primary progressive aphasia (PPA) and apraxia of speech.

    PubMed

    Botha, Hugo; Duffy, Joseph R; Whitwell, Jennifer L; Strand, Edythe A; Machulda, Mary M; Schwarz, Christopher G; Reid, Robert I; Spychalla, Anthony J; Senjem, Matthew L; Jones, David T; Lowe, Val; Jack, Clifford R; Josephs, Keith A

    2015-08-01

    The consensus criteria for the diagnosis and classification of primary progressive aphasia (PPA) have served as an important tool in studying this group of disorders. However, a large proportion of patients remain unclassifiable whilst others simultaneously meet criteria for multiple subtypes. We prospectively evaluated a large cohort of patients with degenerative aphasia and/or apraxia of speech using multidisciplinary clinical assessments and multimodal imaging. Blinded diagnoses were made using operational definitions with important differences compared to the consensus criteria. Of the 130 included patients, 40 were diagnosed with progressive apraxia of speech (PAOS), 12 with progressive agrammatic aphasia, 9 with semantic dementia, 52 with logopenic progressive aphasia, and 4 with progressive fluent aphasia, while 13 were unclassified. The PAOS and progressive fluent aphasia groups were least impaired. Performance on repetition and sentence comprehension was especially poor in the logopenic group. The semantic and progressive fluent aphasia groups had prominent anomia, but only semantic subjects had loss of word meaning and object knowledge. Distinct patterns of grey matter loss and white matter changes were found in all groups compared to controls. PAOS subjects had bilateral frontal grey matter loss, including the premotor and supplementary motor areas, and bilateral frontal white matter involvement. The agrammatic group had more widespread, predominantly left sided grey matter loss and white matter abnormalities. Semantic subjects had bitemporal grey matter loss and white matter changes, including the uncinate and inferior occipitofrontal fasciculi, whereas progressive fluent subjects only had left sided temporal involvement. Logopenic subjects had diffuse and bilateral grey matter loss and diffusion tensor abnormalities, maximal in the posterior temporal region. A diagnosis of logopenic aphasia was strongly associated with being amyloid positive (46

  5. Hypopharynx and larynx defect repair after resection for pyriform fossa cancer with a platysma skin flap.

    PubMed

    Cai, Qian; Liang, Faya; Huang, Xiaoming; Han, Ping; Pan, Yong; Zheng, Yiqing

    2015-02-01

    We used a platysma skin flap to repair larynx and hypopharynx defects to improve postoperative laryngeal function in patients with pyriform fossa cancer. Larynx-sparing surgery and postoperative radiotherapy were used in 10 patients with pyriform fossa cancer. The surgical approaches of lymph node dissection of the neck, vertical partial laryngectomy, and pyriform fossa resection were adopted, and a platysma skin flap was used to repair the resulting defects. In this group, the overall 3-year survival rate was 75% according to the Kaplan-Meier analysis, and the local control rate was 90%. Additionally, all patients were able to speak fluently with mild-to-moderate hoarseness. The tracheal tube was removed in all cases. Laryngeal fistulas were observed in 1 patient during radiotherapy. In conclusion, a platysma skin flap can be used to rebuild the larynx and hypopharynx in larynx-sparing resection for pyriform fossa cancer. These patients can obtain good postoperative function in swallowing, breathing, and pronunciation.

  6. Polygonal Dike Networks in the Medusae Fossae Formation

    NASA Astrophysics Data System (ADS)

    Kerber, L.; Dickson, J. L.; Forget, F.; Head, J. W.; Grosfils, E. B.

    2013-09-01

    1. Introduction 1.1 The Medusae Fossae Formation The Medusae Fossae Formation (MFF) is a widespread and voluminous formation which covers 2.1 x 106 km2 between 130-230ºE and 12ºS-12ºN [1-3]. As a fine-grained, friable deposit, its surface is dominated by aeolian features such as yardangs [3-5] and a large number of both fresh and indurated transverse aeolian ridges [TARs] [5]. The deposition of the MFF began at the latest in the Hesperian [6], and over time it has been recognized that, by virtue of its fine-grained nature, the MFF may preserve an important record of Martian history, most directly as a result of the burial and exhumation of channels found in the Zephyria region of the formation [7]. In order to better document the occurrence of smallscale features of interest within the MFF, we examined 427 High Resolution Imaging Science Experiment (HiRISE) images spread across the formation, during which the occurrence of features of interest were mapped [8]. HiRISE images were supplemented by Mars Reconnaissance Orbiter Context Imager (CTX), Mars Express High Resolution Stereo Camera (HRSC) and Mars Global Surveyor Mars Orbiter Camera (MOC) images where needed. Here we describe the occurrence and characteristics of several polygonal networks of rectilinear ridges. 1.2 Rectilinear Ridges on Mars Rectilinear ridges have been recognized in several different areas on Mars. Long, linear to slightly curving or en echelon ridges hypothesized to be exhumed magmatic dikes have been found in a variety of environments on Mars [9-13], particularly in formerly glaciated terrains where magma may have been emplaced into an icy substrate. A network of rectilinear ridges was described in detail in an unnamed crater on the dichotomy boundary [14]. These chaotic, intersecting ridges, forming irregular polygons ~1 km across, are hypothesized to be brecciated dikes emplaced during the process of crater formation [14]. A group of intersecting rectilinear ridges, informally known as

  7. Unusual Ventilatory Response to Exercise in Patient with Arnold-Chiari Type 1 Malformation after Posterior Fossa Decompression

    PubMed Central

    Smith, Keely; Gomez-Rubio, Ana M.; Harris, Tomika S.; Brooks, Lauren E.

    2016-01-01

    We present a case of a 17-year-old Hispanic male with Arnold-Chiari Type 1 [AC-Type 1] with syringomyelia, status post decompression, who complains of exercise intolerance, headaches, and fatigue with exertion. The patient was found to have diurnal hypercapnia and nocturnal alveolar hypoventilation. Cardiopulmonary testing revealed blunting of the ventilatory response to the rise in carbon dioxide (CO2) resulting in failure of the parallel correlation between increased CO2 levels and ventilation; the expected vertical relationship between PETCO2 and minute ventilation during exercise was replaced with an almost horizontal relationship. No new pathology of the brainstem was discovered by MRI or neurological evaluation to explain this phenomenon. The patient was placed on continuous noninvasive open ventilation (NIOV) during the day and CPAP at night for a period of 6 months. His pCO2 level decreased to normal limits and his symptoms improved; specifically, he experienced less headaches and fatigue during exercise. In this report, we describe the abnormal response to exercise that patients with AC-Type 1 could potentially experience, even after decompression, characterized by the impairment of ventilator response to hypercapnia during exertion, reflecting a complete loss of chemical influence on breathing with no evidence of abnormality in the corticospinal pathway. PMID:27418995

  8. Acoustic interaction between the right and left piriform fossae in generating spectral dips.

    PubMed

    Takemoto, Hironori; Adachi, Seiji; Mokhtari, Parham; Kitamura, Tatsuya

    2013-10-01

    It is known that the right and left piriform fossae generate two deep dips on speech spectra and that acoustic interaction exists in generating the dips: if only one piriform fossa is modified, both the dips change in frequency and amplitude. In the present study, using a simple geometrical model and measured vocal tract shapes, the acoustic interaction was examined by the finite-difference time-domain method. As a result, one of the two dips was lower in frequency than the two independent dips that appeared when either of the piriform fossae was occluded, and the other dip was higher in frequency than the two dips. At the lower dip frequency, the piriform fossae resonated almost in opposite phase, while at the higher dip frequency, they resonated almost in phase. These facts indicate that the piriform fossae and the lower part of the pharynx can be modeled as a coupled two-oscillator system whose two normal vibration modes generate the two spectral dips. When the piriform fossae were identical, only the higher dip appeared. This is because the lower mode is not acoustically coupled to the main vocal tract enough to generate an absorption dip.

  9. Clinico-Radiological Correlation in a Cohort of Cervical Myelopathy Patients

    PubMed Central

    Kalpana, R.Y.

    2015-01-01

    Objective: Though both clinical evaluation and MRI are complimentary in detection and precise localization of the level of lesion in patients with cervical myelopathy, there is paucity of data comparing segment specific clinical features with the MRI abnormalities in cervical myelopathy. Materials and Methods: Thirty one patients with cervical myelopathy and abnormal MRI of the cervical spine (signal changes in the cord) admitted to the neurology and neurosurgery wards during the study period were included in the study. The patients were prospectively evaluated by a detailed neurological examination. Clinically, the site of lesion was determined by highest of the pyramidal, sensory or segmental features of involvement. The MRI lesions were categorized based on the vertebral level at which the abnormalities were seen. The patients were divided into three groups according to the site of lesion on MRI: (1) cervico-medullary (foramen magnum to C1) lesions (2) upper cervical (C2-C4) lesions and (3) lower cervical (C5-T1) lesions. Comparisons of clinical symptoms, signs and level of lesion with MRI abnormalities were done and the level of significance was set at p < 0.05. Results: Clinical evaluation showed limb weakness in all, sensory loss in 90%, sphincter disturbances in 67.7%, scissoring gait in 32.2%, diaphragmatic weakness in 12.9% of patients. Based on clinical examination the site of lesion was cervico-medullary in 9, upper cervical region in 4 and lower cervical region of involvement in five patients. The maximal antero-posterior extent of the lesion and neurological deficits were concordant (p-0.05). As compared to pyramidal signs or sensory abnormalities, segmental features – segmental sensory loss, weakness, wasting or ‘reflex’ loss – were most concordant with the MRI level of lesion (p - 0.03). Among ‘motor’, ‘sensory’ and ‘reflex’ levels, the ‘reflex (DTR)’ levels were most concordant with the MRI level of lesion (p – 0

  10. Pedestal Craters and Wind Streaks, South Medusae Fossae

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Mars is a desert planet in which wind has a considerable effect on the landscape. Bright and dark wind streaks in this image indicate past movement of fine sediment across the landscape from upper left toward lower right. Two impact craters that look like flowers or starfish are seen in the lower portion of the image. The ejecta deposits of these craters are raised above the surrounding terrain, and indicate that wind has deflated a layer of material (that is, blown it away, thus lowering the surface) that was present at the time that the craters formed. The craters were formed by impacts of meteorites into the earlier, higher surface, and the rocks and gravel thrown out when they formed protected some of this former layer from the wind's effects. This picture--showing part of the Medusae Fossae region near the martian equator--was taken in early April 1999 and covers an area only 1 kilometer (0.62 miles)wide. Illumination is from the lower right.

    Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

  11. Posterior Circulation Ischemic Stroke.

    PubMed

    Go, Steven

    2015-01-01

    Approximately 20-25% of all acute strokes occur in the posterior circulation. These strokes can be rather difficult to diagnose because they present in such diverse ways, and can easily be mistaken for more benign entities. A fastidious history, physical exam, high clinical suspicion, and appropriate use of imaging are essential for the emergency physician to properly diagnose and treat these patients. Expert stroke neurologist consultation should be utilized liberally.

  12. Ossification of the Posterior Petroclinoid Dural Fold: A Cadaveric Study with Neurosurgical Significance

    PubMed Central

    Kimball, David; Kimball, Heather; Matusz, Petru; Tubbs, R. Shane; Loukas, Marios; Cohen-Gadol, A. Aaron

    2015-01-01

    Objectives The roof of the porus trigeminus, composed of the posterior petroclinoid dural fold, is an important landmark to the skull base surgeon. Ossification of the posterior petroclinoid dural fold is an anatomical variation rarely mentioned in the literature. Such ossification results in the trigeminal nerve traversing a bony foramen as it enters Meckel cave. The authors performed this study to better elucidate this anatomical variation. Design Fifteen adult cadaveric head halves were subjected to dissection of the middle cranial fossa. Microdissection techniques were used to examine the posterior petroclinoid dural folds. Skull base osteology was also studied in 71 dry human skulls with attention paid to the attachment point of the posterior petroclinoid dural folds at the trigeminal protuberances. Setting Cadaver laboratory Main Outcome Measures Measurements were made using a microcaliper. Digital images were made of the dissections. Results Completely ossified posterior petroclinoid folds were present in 20% of the specimens. Of the 142 dry skull sides examined, 9% had large trigeminal protuberances. Conclusions Based on this study, the posterior petroclinoid dural fold may completely ossify in adults that may lead to narrowing of the porus trigeminus and potential compression of the trigeminal nerve at the entrance to Meckel cave. PMID:26225315

  13. Relative placement of the mandibular fossa in great apes and humans.

    PubMed

    Sherwood, Richard J; Rowley, Rebecca B; Ward, Steven C

    2002-07-01

    Several researchers have investigated, or commented on, the relative placement of the hominin mandibular fossa with regard to brain expansion and masticatory function. Two confounding factors are identified in this previous work. First, a number of different measurement techniques have been applied, confusing comparisons between studies. Second, the effects of squamous thickening due to temporal bone pneumatization are shown to influence measurements based relative to the ectocranial margin of the skull. To investigate the influence of these factors, a sample of adult human (n=12), chimpanzee (n=12), gorilla (n=15), and orang-utan (n=8) skulls from the Cleveland Museum of Natural History, University of Wisconsin Zoology Museum, and University of Wisconsin Anthropology collections, were CT scanned. Coronal scans were horizontally aligned and measured on a personal computer using ImageJ (NIH). To identify fossa placement, fossa breadth was measured as the projected distance in the coronal plane between the tip of the entoglenoid to lateral margin of the articular surface. A second distance, from the tip of the entoglenoid to a sagittal plane, tangent to the lateralmost margin of the endocranial surface was taken to indicate the extent of medial placement of the fossa. By eliminating the influence of pneumatization, these data unambiguously confirmed the medial placement of the human fossa and show all great apes as having a laterally placed fossa. Similar measurements on three fossil hominins, KNM-BC 1 (Homo sp. indet.), OH 5 and KNM-ER 23000 (Paranthropus boisei) demonstrate that, while all specimens demonstrate a broad fossa, only KNM-BC 1 is characterized by a relatively medial placement while the latter two display lateral placement.

  14. Medusae Fossae Formation: New perspectives from Mars Global Surveyor

    NASA Astrophysics Data System (ADS)

    Bradley, Bethany A.; Sakimoto, Susan E. H.; Frey, Herbert; Zimbelman, James R.

    2002-08-01

    The nature and origin of the Medusae Fossae Formation (MFF) on Mars has been debated since the return of the first Viking images. The MFF's young age, distinctive surface texture, and lack of obvious source have prompted multiple hypotheses for its origin. This study uses data from the Mars Global Surveyor (MGS) mission to examine the MFF at all available scales. We discuss and quantify observations from Mars Orbiter Laser Altimeter (MOLA) topography and Mars Orbiter Camera (MOC) images to better constrain the origin of the MFF. Topographic grid estimates yield a present extent of 2.1 × 106 km2 and a volume of 1.4 × 106 km3; however, remnant yardang deposits observed far from the thicker lobes of MFF material suggest that it may have once covered up to 5 × 106 km2. We do not find compelling evidence for extensive fluvial reworking of the MFF; however, in several regions, buried channels are apparent in the MFF because the formation is draped over underlying topography. Layering is apparent at all scales, from submeter to hundreds of meters, with variable resistance to weathering. Continuity of layers appears to be local to regional, but not likely formation-wide. Yardangs form both parallel and bidirectional patterns, with resistant layers and jointing probably influencing their orientations. A comparative study of MFF regional topography and surface expression indicates that the MFF is quantitatively dissimilar to Martian polar layered deposits. The material is most likely a friable and irregularly consolidated air fall deposit of probable volcanic origin.

  15. Morphological study of fossa ovalis and its clinical relevance

    PubMed Central

    Joshi, S.D.; Chawre, H.K.; Joshi, S.S.

    2016-01-01

    Aims Patent foramen ovale (PFO) has been implicated in the etiology of a number of different pathologies, including cryptogenic stroke, decompression sickness in divers, etc. It can act as a channel for paradoxical embolism. PFO is not an uncommon condition, with a probe-patency in 15–35% population. The fossa ovalis (FOv) varies in size and shape from heart to heart; the prominence of annulus FOv also varies. The entire FOv may be redundant and aneurysmal. The anatomico-functional characterization of interatrial septum seems to be of paramount importance for both atrial septal defect (ASD) and PFO, not only for the device selection, but also for the evaluation of the outcome of this procedure. Method This study was conducted in 50 apparently normal hearts available in Department of Anatomy. After opening the right atrium, the shape of FOv was observed. The size was measured with the digital vernier caliper; the prominence and extent of limbus, and the redundancy or otherwise of FOv were noted; probe patency was confirmed. Results In the majority, FOv was oval (82%); average transverse diameter was 14.53 mm and vertical 12.60 mm. In 90%, the rim of the annulus was raised; in 20%, a recess was found deep to the margin of the annulus; and 18% showed probe patency. Conclusion As no study of this nature has been carried out in the Indian population, this provides pertinent information on the morphology of FOv, which may be useful for device selection in treating ASD and PFO. PMID:27133322

  16. Posterior interosseous neuropathy

    PubMed Central

    Kele, Henrich; Xia, Annie; Weiler, Markus; Schwarz, Daniel; Bendszus, Martin; Pham, Mirko

    2016-01-01

    Objective: To investigate the spatial pattern of lesion dispersion in posterior interosseous neuropathy syndrome (PINS) by high-resolution magnetic resonance neurography. Methods: This prospective study was approved by the local ethics committee and written informed consent was obtained from all patients. In 19 patients with PINS and 20 healthy controls, a standardized magnetic resonance neurography protocol at 3-tesla was performed with coverage of the upper arm and elbow (T2-weighted fat-saturated: echo time/repetition time 52/7,020 milliseconds, in-plane resolution 0.27 × 0.27 mm2). Lesion classification of the radial nerve trunk and its deep branch (which becomes the posterior interosseous nerve) was performed by visual rating and additional quantitative analysis of normalized T2 signal of radial nerve voxels. Results: Of 19 patients with PINS, only 3 (16%) had a focal neuropathy at the entry of the radial nerve deep branch into the supinator muscle at elbow/forearm level. The other 16 (84%) had proximal radial nerve lesions at the upper arm level with a predominant lesion focus 8.3 ± 4.6 cm proximal to the humeroradial joint. Most of these lesions (75%) followed a specific somatotopic pattern, involving only those fascicles that would form the posterior interosseous nerve more distally. Conclusions: PINS is not necessarily caused by focal compression at the supinator muscle but is instead frequently a consequence of partial fascicular lesions of the radial nerve trunk at the upper arm level. Neuroimaging should be considered as a complementary diagnostic method in PINS. PMID:27683851

  17. Posterior Urethral Strictures

    PubMed Central

    Gelman, Joel; Wisenbaugh, Eric S.

    2015-01-01

    Pelvic fracture urethral injuries are typically partial and more often complete disruptions of the most proximal bulbar and distal membranous urethra. Emergency management includes suprapubic tube placement. Subsequent primary realignment to place a urethral catheter remains a controversial topic, but what is not controversial is that when there is the development of a stricture (which is usually obliterative with a distraction defect) after suprapubic tube placement or urethral catheter removal, the standard of care is delayed urethral reconstruction with excision and primary anastomosis. This paper reviews the management of patients who suffer pelvic fracture urethral injuries and the techniques of preoperative urethral imaging and subsequent posterior urethroplasty. PMID:26691883

  18. Symptomatic posterior mediastinal angioleiomyoma.

    PubMed

    I, Hoseok; Jeong, Yeon Joo; Choi, Kyung Un; Kim, Yeong-Dae

    2008-08-30

    We report a case of a symptomatic angioleiomyoma in the left posterior mediastinum. A 66-year-old woman presented with left back and flank pain for 6 months. Chest computed tomography (CT) and magnetic resonance imaging (MRI) revealed a well-circumscribed 4.3 cm round mass. The mass was initially diagnosed as nerve sheath tumor, because of her symptoms and its close location to the sympathetic trunk and intercostal nerve. It was uneventfully removed through video-assisted thoracoscopic surgery. The pathology revealed an angioleiomyoma.

  19. Posterior Cortical Atrophy

    PubMed Central

    Crutch, Sebastian J; Lehmann, Manja; Schott, Jonathan M; Rabinovici, Gil D; Rossor, Martin N; Fox, Nick C

    2013-01-01

    Posterior cortical atrophy (PCA) is a neurodegenerative syndrome that is characterized by a progressive decline in visuospatial, visuoperceptual, literacy and praxic skills. The progressive neurodegeneration affecting parietal, occipital and occipito-temporal cortices which underlies PCA is attributable to Alzheimer's disease (AD) in the majority of patients. However, alternative underlying aetiologies including Dementia with Lewy Bodies (DLB), corticobasal degeneration (CBD) and prion disease have also been identified, and not all PCA patients have atrophy on clinical imaging. This heterogeneity has led to diagnostic and terminological inconsistencies, caused difficulty comparing studies from different centres, and limited the generalizability of clinical trials and investigations of factors driving phenotypic variability. Significant challenges remain in identifying the factors associated with both the selective vulnerability of posterior cortical regions and the young age of onset seen in PCA. Greater awareness of the syndrome and agreement over the correspondence between syndrome-and disease-level classifications are required in order to improve diagnostic accuracy, research study design and clinical management. PMID:22265212

  20. Is Mandibular Fossa Morphology and Articular Eminence Inclination Associated with Temporomandibular Dysfunction?

    PubMed Central

    Paknahad, Maryam; Shahidi, Shoaleh; Akhlaghian, Marzieh; Abolvardi, Masoud

    2016-01-01

    Statement of the Problem Finding a significant relationship between temporomandibular joint (TMJ) morphology and the incidence of temporomandibular dysfunction (TMD) may help early prediction and prevention of these problems. Purpose The purpose of the present study was to determine the morphology of mandibular fossa and the articular eminence inclination in patients with TMD and in control group using cone beam computed tomography (CBCT). Materials and Method The CBCT data of bilateral TMJs of 40 patients with TMD and 23 symptom-free cases were evaluated. The articular eminence inclination, as well as the glenoid fossa depth and width of the mandibular fossa were measured. The paired t-test was used to compare these values between two groups. Results The articular eminence inclination and glenoid fossa width and depth were significantly higher in patients with TMD than in the control group (p < 0.05). Conclusion The articular eminence inclination was steeper in patients with TMD than in the control group. Glenoid fossa width and depth were higher in patients with TMD than that in the control group. This information may shed light on the relationship between TMJ morphology and the incidence of TMD. PMID:27284559

  1. Scene perception in posterior cortical atrophy: categorization, description and fixation patterns.

    PubMed

    Shakespeare, Timothy J; Yong, Keir X X; Frost, Chris; Kim, Lois G; Warrington, Elizabeth K; Crutch, Sebastian J

    2013-01-01

    Partial or complete Balint's syndrome is a core feature of the clinico-radiological syndrome of posterior cortical atrophy (PCA), in which individuals experience a progressive deterioration of cortical vision. Although multi-object arrays are frequently used to detect simultanagnosia in the clinical assessment and diagnosis of PCA, to date there have been no group studies of scene perception in patients with the syndrome. The current study involved three linked experiments conducted in PCA patients and healthy controls. Experiment 1 evaluated the accuracy and latency of complex scene perception relative to individual faces and objects (color and grayscale) using a categorization paradigm. PCA patients were both less accurate (faces < scenes < objects) and slower (scenes < objects < faces) than controls on all categories, with performance strongly associated with their level of basic visual processing impairment; patients also showed a small advantage for color over grayscale stimuli. Experiment 2 involved free description of real world scenes. PCA patients generated fewer features and more misperceptions than controls, though perceptual errors were always consistent with the patient's global understanding of the scene (whether correct or not). Experiment 3 used eye tracking measures to compare patient and control eye movements over initial and subsequent fixations of scenes. Patients' fixation patterns were significantly different to those of young and age-matched controls, with comparable group differences for both initial and subsequent fixations. Overall, these findings describe the variability in everyday scene perception exhibited by individuals with PCA, and indicate the importance of exposure duration in the perception of complex scenes.

  2. Novel posterior fixation keratoprosthesis

    NASA Astrophysics Data System (ADS)

    Lacombe, Emmanuel

    1992-08-01

    The keratoprosthesis is the last solution for corneally blind patients that cannot benefit from corneal transplants. Keratoprostheses that have been designed to be affixed anteriorly usually necessitate multi-step surgical procedures and are continuously subjected to the extrusion forces generated by the positive intraocular pressure; therefore, clinical results in patients prove inconsistent. We proposed a novel keratoprosthesis concept that utilizes posterior corneal fixation which `a priori' minimizes the risk of aqueous leakage and expulsion. This prosthesis is implanted in a single procedure thereby reducing the number of surgical complications normally associated with anterior fixation devices. In addition, its novel design makes this keratoprosthesis implantable in phakic eyes. With an average follow-up of 13 months (range 3 to 25 months), our results on 21 cases are encouraging. Half of the keratoprostheses were implanted in severe burn cases, with the remainder in cases of pseudo- pemphigus. Good visual results and cosmetic appearance were obtained in 14 of 21 eyes.

  3. Posterior pole tumor update.

    PubMed

    Ou, Judy I; Wheeler, Sharon M; O'Brien, Joan M

    2002-12-01

    This chapter focuses on the diagnosis and management of choroidal melanoma in light of recent findings from the COMS. Retinoblastoma is emphasized to describe recent trends in primary treatment away from EBRT and toward chemoreduction with local therapy. In addition, vascular and glial tumors of the retina and tumors of the retinal pigment epithelium are described because of the association between these lesions and systemic disease. Recent advances in treatment and genetic testing for these diseases are discussed. Finally, ocular metastasis, intraocular lymphoid tumors, and intraocular leukemia are included because of their importance in determining systemic treatment and prognosis. The chapter gives an overview of important posterior pole tumors and highlights recent developments in the management of each intraocular disease process.

  4. Endoscopic Endonasal Approach to the Middle Cranial Fossa through the Cavernous Sinus Triangles: Anatomical Considerations

    PubMed Central

    KOMATSU, Fuminari; ODA, Shinri; SHIMODA, Masami; IMAI, Masaaki; SHIGEMATSU, Hideaki; KOMATSU, Mika; TSCHABITSCHER, Manfred; MATSUMAE, Mitsunori

    2014-01-01

    The lateral limit of endoscopic endonasal surgery has yet to be defined. The aim of this study was to investigate the lateral limit of endoscopic endonasal surgery at the level of the sphenoid sinus. Access from the sphenoid sinus to the middle cranial fossa through the cavernous sinus triangles was evaluated by cadaver dissection. Anatomical analysis demonstrated that the medial temporal dura mater was exposed through the anterior area of the clinoidal triangle, anteromedial triangle, and superior area of the anterolateral triangle, indicating potential corridors to the middle cranial fossa. This study suggests that the cavernous sinus triangles are applicable in selected cases to manage middle cranial fossa lesions by endoscopic endonasal surgery. PMID:25446385

  5. Displacement of a maxillary third molar into the infratemporal fossa: case report.

    PubMed

    Dimitrakopoulos, Ioannis; Papadaki, Maria

    2007-01-01

    The case of a maxillary third molar displaced into the infratemporal fossa, with difficulty in localization due to the synchronous creation of oroantral communication, is described in this article. The patient was referred to the oral and maxillofacial department and underwent successful surgical treatment through an intraoral access. The causes of tooth displacement into the infratemporal fossa, the aid of a computerized tomography (CT) scan in tooth localization, and the difficulty in treating this complication, particularly when the tooth migrates toward the base of the skull, are emphasized. Prevention of maxillary third molar displacement into the infratemporal fossa predominates over removal and is achieved by adequate flap design, correct extraction technique, and a distal retractor during surgical extraction. In the case of displacement, no effort to retrieve the tooth is recommended because of the risk of hemorrhage, neurologic injury, and further displacement of the tooth. The patient should be treated with antibiotics and referred to an oral and maxillofacial department.

  6. Delayed removal of a maxillary third molar from the infratemporal fossa.

    PubMed

    Gómez-Oliveira, Guillermo; Arribas-García, Ignacio; Alvarez-Flores, Modesto; Gregoire-Ferriol, Johanna; Martínez-Gimeno, Carlos

    2010-05-01

    Removal of an impacted superior third molar is usually a simple and uncomplicated procedure for an Oral and Maxillofacial Surgeon. Nevertheless, complications are possible and include infection, facial swallowing, trismus, wound dehiscence, root fracture or even orosinusal fistula. Iatrogenic displacement into the infratemporal fossa is frequently mentioned but rarely reported. This anatomical fossa includes several important structures such as the internal maxillary artery, the venous pterygoid plexus, the sphenopalatine nerve, the coronoid process of the mandible and the pterygoid muscles. Recommended treatment includes immediate surgical removal if possible or initial observation and secondary removal, as necessary, because of infection, limited mandibular movement, inability to extract the tooth, or the patient's psychological unease. Sometimes, the displaced tooth may spontaneously migrate inferiorly and becomes accessible intraorally. This report describes the location and secondary surgical removal of a left maxillary third molar displaced into the infratemporal fossa, two weeks after first attempt at extraction.

  7. Unusual anatomical detection of a third molar in the infratemporal fossa.

    PubMed

    Corega, C; Vaida, L; Festila, D; Bertossi, D

    2013-01-01

    Third molar presence in the infratemporal fossa is a rare event and it has been reported previously only two times in the literature, except for the cases which arise from complications occurring during the extraction of the impacted upper third molar. Due to the presence of important vessel bundles and nerves in this area, third molar removal requires a correct surgical management in order to avoid many possible serious side effects. We report an unusual case of upper third molar detected in the infratemporal fossa, which has been thoroughly investigated radiologically and removed through a safe surgical approach.

  8. Small-Scale Features of the Medusae Fossae Formation: Do They Support a Volcanic Origin?

    NASA Astrophysics Data System (ADS)

    Kerber, L.

    2013-12-01

    The Medusae Fossae Formation is a widespread and voluminous fine-grained deposit that lies just north of the Martian equator along the dichotomy boundary. It is thought to consist of pyroclastic deposits, either in the form of pyroclastic flows or ashfall, though numerous other possibilities have been suggested, including wind-blown loess and icy dust. For this work a survey was conducted of 427 High Resolution Imaging Science Experiment (HiRISE) images spread across the Medusae Fossae Formation. From these images maps were created of small-scale features which can aid in distinguishing between formation hypotheses for the deposit, including rootless cones, jointing, layering, and exposed dikes. Relationships between the Medusae Fossae Formation and adjacent lava plains and volcanoes were also carefully examined using HiRISE, Mars Reconnaissance Orbiter Context Imager (CTX), Mars Express High Resolution Stereo Camera (HRSC), and Mars Global Surveyor Mars Orbital Camera (MOC) images. The interactions between the Medusae Fossae Formation and nearby lava flows can inform us about the chronology of the deposit as well as how it has eroded over time. Certain diagnostic volcanic features were found, but mostly close to deposit boundaries where there are lava flows. The morphologies of the formation are compared with those of terrestrial pyroclastic deposits, terrestrial loess deposits, and other icy dust deposits on Mars. It is found that while the deposit is morphologically unlike icy layered deposits in most places, distinguishing between pyroclastic flow morphologies and reworked aeolian morphologies is more ambiguous.

  9. Geomorphic Mapping and Analysis of the Eastern Medusae Fossae Region of Mars

    NASA Technical Reports Server (NTRS)

    Takagi, M.; Zimbelman, J. R.

    2001-01-01

    A geomorphic map of the MC-8SE quadrangle on Mars is used to examine hypotheses of origin for the Medusae Fossae Formation, as well as to characterize the regional setting of these enigmatic materials. Additional information is contained in the original extended abstract.

  10. Increased depth-diameter ratios in the Medusae Fossae Formation deposits of Mars

    NASA Technical Reports Server (NTRS)

    Barlow, N. G.

    1993-01-01

    Depth to diameter ratios for fresh impact craters on Mars are commonly cited as approximately 0.2 for simple craters and 0.1 for complex craters. Recent computation of depth-diameter ratios in the Amazonis-Memnonia region of Mars indicates that craters within the Medusae Fossae Formation deposits found in this region display greater depth-diameter ratios than expected for both simple and complex craters. Photoclinometric and shadow length techniques have been used to obtain depths of craters within the Amazonis-Memnonia region. The 37 craters in the 2 to 29 km diameter range and displaying fresh impact morphologies were identified in the area of study. This region includes the Amazonian aged upper and middle members of the Medusae Fossae Formation and Noachian aged cratered and hilly units. The Medusae Fossae Formation is characterized by extensive, flat to gently undulating deposits of controversial origin. These deposits appear to vary from friable to indurated. Early analysis of crater degradation in the Medusae Fossae region suggested that simple craters excavated to greater depths than expected based on the general depth-diameter relationships derived for Mars. However, too few craters were available in the initial analysis to estimate the actual depth-diameter ratios within this region. Although the analysis is continuing, we are now beginning to see a convergence towards specific values for the depth-diameter ratio depending on geologic unit.

  11. Snapshot quiz - recurrent right iliac fossa pain in the patient with a previous history of appendicitis.

    PubMed

    Aris Chandran, Johan; Cobb, Will A; Keeler, Barrie D; Soin, Bob

    2015-06-01

    A low threshold for computed tomography (CT) scanning in patients with previous appendicectomy and right iliac fossa pain helps facilitate timely diagnosis and exclusion of other differential diagnoses. Here, we present a rare cause which has significant medicolegal ramifications and is accurately diagnosed with CT.

  12. MOLA Topography of Small Volcanoes in Tempe Terra and Ceraunius Fossae, Mars: Implications for Eruptive Styles

    NASA Technical Reports Server (NTRS)

    Wong, M. P.; Sakimoto, S. E. H.; Garvin, J. B.

    2001-01-01

    We use Mars Orbiter Laser Altimeter (MOLA) data to measure small volcanoes in the Tempe Terra and Ceraunius Fossae regions of Mars. We find that previous geometry estimates based on imagery alone are inaccurate, but MOLA data support image-based interpretations of eruptive style. Additional information is contained in the original extended abstract.

  13. Dislocation of the mandibular condyle into the middle cranial fossa causing an epidural haematoma.

    PubMed

    Struewer, Johannes; Kiriazidis, Ilias; Figiel, Jens; Dukatz, Thomas; Frangen, Thomas; Ziring, Ewgeni

    2012-07-01

    Dislocation of the mandibular condyle into the middle cranial fossa is a rare complication of mandibular trauma due to anatomical and biomechanical factors. Owing to the proximity of the temporal glenoid fossa to the middle meningeal artery, there is the risk of serious sequelae in case of trauma. The authors report the case of a 36-year-old male patient, who was beaten up in a family dispute and presented with complex mandibular and maxillofacial fractures, including mandibular condyle intrusion into the middle cranial fossa causing extensive meningeal bleeding. The patient underwent immediate surgery, with evacuation of the epidural haematoma via a temporal approach. In addition open reduction and reconstruction of the temporal glenoid fossa via anatomic reduction of the fragments was performed. A functional occlusion was re-established via miniplate reconstruction of the complex mandibular body and ramus fractures. Prompt diagnosis and a multidisciplinary approach are essential to minimize the complications. Advanced imaging modalities of computed tomography are indicated. Treatment options should be individualized in particular in case of suspected neurological injury.

  14. Age and sex related differences in normal pituitary gland and fossa volumes.

    PubMed

    Pecina, Hrvoje Ivan; Pecina, Tatjana Cicvara; Vyroubal, Vlasta; Kruljac, Ivan; Slaus, Mario

    2017-03-01

    This study investigates the influence of age and sex on the volumes of the pituitary fossa and gland in 91 males and 108 females from Croatia who underwent magnetic resonance imaging of the endocranium for complaints not related to the pituitary gland. Isometric 3DT1 MPRAGE and 3DT1 MPR sequences were obtained on 1.5. Tesla and analysed on ISSA software. The volumes were obtained from the sum of all the areas multiplied by the thickness of the section. The mean volume of the pituitary fossa for males was 1111.1.4 mm(3), for females 1354.4.2 mm(3). Correlation analysis showed a significant negative correlation (P=0.0.09) between age of the patient, and pituitary volume. Age of the patient and free volume demonstrate a significant positive correlation (P=0.0.01) indicating that the amount of unoccupied space in the pituitary fossa significantly increases with age. Determining general morphological values, as well as variations of pituitary depth and the occupation of the fossa with the pituitary gland is of great help in everyday diagnostic and therapeutic approach.

  15. Geomorphology and structural geology of Saturnalia Fossae and adjacent structures in the northern hemisphere of Vesta

    NASA Astrophysics Data System (ADS)

    Scully, Jennifer E. C.; Yin, A.; Russell, C. T.; Buczkowski, D. L.; Williams, D. A.; Blewett, D. T.; Ruesch, O.; Hiesinger, H.; Le Corre, L.; Mercer, C.; Yingst, R. A.; Garry, W. B.; Jaumann, R.; Roatsch, T.; Preusker, F.; Gaskell, R. W.; Schröder, S. E.; Ammannito, E.; Pieters, C. M.; Raymond, C. A.

    2014-12-01

    Vesta is a unique, intermediate class of rocky body in the Solar System, between terrestrial planets and small asteroids, because of its size (average radius of ∼263 km) and differentiation, with a crust, mantle and core. Vesta's low surface gravity (0.25 m/s2) has led to the continual absence of a protective atmosphere and consequently impact cratering and impact-related processes are prevalent. Previous work has shown that the formation of the Rheasilvia impact basin induced the equatorial Divalia Fossae, whereas the formation of the Veneneia impact basin induced the northern Saturnalia Fossae. Expanding upon this earlier work, we conducted photogeologic mapping of the Saturnalia Fossae, adjacent structures and geomorphic units in two of Vesta's northern quadrangles: Caparronia and Domitia. Our work indicates that impact processes created and/or modified all mapped structures and geomorphic units. The mapped units, ordered from oldest to youngest age based mainly on cross-cutting relationships, are: (1) Vestalia Terra unit, (2) cratered highlands unit, (3) Saturnalia Fossae trough unit, (4) Saturnalia Fossae cratered unit, (5) undifferentiated ejecta unit, (6) dark lobate unit, (7) dark crater ray unit and (8) lobate crater unit. The Saturnalia Fossae consist of five separate structures: Saturnalia Fossa A is the largest (maximum width of ∼43 km) and is interpreted as a graben, whereas Saturnalia Fossa B-E are smaller (maximum width of ∼15 km) and are interpreted as half grabens formed by synthetic faults. Smaller, second-order structures (maximum width of <1 km) are distinguished from the Saturnalia Fossae, a first-order structure, by the use of the general descriptive term 'adjacent structures', which encompasses minor ridges, grooves and crater chains. For classification purposes, the general descriptive term 'minor ridges' characterizes ridges that are not part of the Saturnalia Fossae and are an order of magnitude smaller (maximum width of <1 km vs

  16. Posterior sampling with improved efficiency

    SciTech Connect

    Hanson, K.M.; Cunningham, G.S.

    1998-12-01

    The Markov Chain Monte Carlo (MCMC) technique provides a means to generate a random sequence of model realizations that sample the posterior probability distribution of a Bayesian analysis. That sequence may be used to make inferences about the model uncertainties that derive from measurement uncertainties. This paper presents an approach to improving the efficiency of the Metropolis approach to MCMC by incorporating an approximation to the covariance matrix of the posterior distribution. The covariance matrix is approximated using the update formula from the BFGS quasi-Newton optimization algorithm. Examples are given for uncorrelated and correlated multidimensional Gaussian posterior distributions.

  17. TMJ in facial class III deformity. Condyle/fossa relations

    PubMed Central

    Muñoz, Gonzalo; Olate, Sergio; Cantín, Mario; Vásquez, Bélgica; del Sol, Mariano; Fariña, Rodrigo

    2014-01-01

    The aim of this study was to ascertain the joint space present in the TMJ of subjects diagnosed with Class III dentofacial deformity with an indication for orthognathic surgery. Fourteen subjects were recruited from the Division of Oral and Maxillofacial Surgery at the Universidad de La Frontera, Chile. All subjects were admitted to the study after signing an informed consent and undergoing cephalometric analyses to define the severity of the deformity. Then, the joint space was analyzed, studying a cone beam CT image of the TMJ, which was evaluated in the coronal and sagittal views, defining the most anterior, median and posterior joint space (sagittal view), as well as the lateral, median and medial joint space (coronal view). The data were recorded in millimeters by an observer and data were analyzed after measuring the same parameter at three different times. A student’s t-test was used for the analyses. Differences observed in both joints were not greater than 0.2 mm with spaces between 2 mm and 1.5 mm, thereby establishing the homogeneity of the sample, which presented no significant differences between the two joint spaces (right and left). It can be concluded that the joint space is symmetrical in both condyles and that no important changes are present compared to the results indicated in the international literature. PMID:25356133

  18. TMJ in facial class III deformity. Condyle/fossa relations.

    PubMed

    Muñoz, Gonzalo; Olate, Sergio; Cantín, Mario; Vásquez, Bélgica; Del Sol, Mariano; Fariña, Rodrigo

    2014-01-01

    The aim of this study was to ascertain the joint space present in the TMJ of subjects diagnosed with Class III dentofacial deformity with an indication for orthognathic surgery. Fourteen subjects were recruited from the Division of Oral and Maxillofacial Surgery at the Universidad de La Frontera, Chile. All subjects were admitted to the study after signing an informed consent and undergoing cephalometric analyses to define the severity of the deformity. Then, the joint space was analyzed, studying a cone beam CT image of the TMJ, which was evaluated in the coronal and sagittal views, defining the most anterior, median and posterior joint space (sagittal view), as well as the lateral, median and medial joint space (coronal view). The data were recorded in millimeters by an observer and data were analyzed after measuring the same parameter at three different times. A student's t-test was used for the analyses. Differences observed in both joints were not greater than 0.2 mm with spaces between 2 mm and 1.5 mm, thereby establishing the homogeneity of the sample, which presented no significant differences between the two joint spaces (right and left). It can be concluded that the joint space is symmetrical in both condyles and that no important changes are present compared to the results indicated in the international literature.

  19. Posterior Interosseous Nerve Syndrome Resulting from Parosteal Lipoma of the Proximal Radius: An Elusive Diagnosis Yet Excellent Outcome

    PubMed Central

    Saaiq, Muhammad; Siddiui, Saad

    2017-01-01

    A 53-year old man presented with seven months history of progressive weakness of extension of the digits and the thumb of the left hand. The wrist extension was normal and sensations were also intact. The patient had also been noticing a progressively enlarging lump on the lower anterolateral aspect of the left antecubital fossa for the last three months. Physical examination andelectro diagnostic studies revealed motor deficit along the posterior interosseous nerve (PIN) distribution with preservation of sensations. Also a soft tissue solitary lump (measuring 6×5 cm in its greatest dimensions) was palpable in the left antecubital fossa. The magnetic resonance imaging (MRI) of the forearm revealed a well-defined, non-enhancing, homogenous, fat intensity lesion in the left antecubital fossa, attached to the proximal radius. The patient underwent surgical excision of the lump with decompression of the PIN in the radial tunnel. Histopathology confirmed the diagnosis of parosteal lipoma. Although the diagnosis was elusive at the very outset, yet prudent clinical judgment, appropriate ancillary investigations and timely surgical intervention resulted in optimal functional recovery of the hand drop. There was complete motor recovery at 4-months follow up with no recurrence of the lipomaafter one year. PMID:28289621

  20. A Pilot Study on Clinical and Neuroimaging Characteristics of Chinese Posterior Cortical Atrophy: Comparison with Typical Alzheimer’s Disease

    PubMed Central

    Shi, Zhihong; Cai, Li; Liu, Shuai; Liu, Shuling; Han, Tong; Wang, Ying; Zhou, Yuying; Wang, Xinping; Gao, Shuo; Ji, Yong

    2015-01-01

    Posterior cortical atrophy (PCA) is a clinicoradiologic neurodegenerative syndrome characterized by predominant impairment of higher visual functions. Neuroimaging and neuropathological studies show that PCA is probably an atypical presentation of Alzheimer’s disease. However, in China PCA has rarely been studied and remains largely unknown. Our study therefore aimed to analyze the clinical manifestations and patterns of cerebral atrophy, amyloid beta deposition and regional glucose metabolism in Chinese PCA patients, comparing them directly with those of typical Alzheimer’s disease (TAD). Seven PCA patients, 6 TAD patients and 5 controls underwent neuropsychological assessment, MRI scan, 11C-PIB PET scan and 18F-FDG PET scan. Cerebral atrophy including ventricular enlargement, posterior atrophy and medial temporal lobe atrophy were evaluated with MRI. The uptake of 11C-PIB was quantified at the voxel level using the standardized uptake value ratio. Comparisons of regional cerebral glucose metabolism were calculated with statistical parametric mapping. PCA patients showed significant impairment on visuospatial function in neuropsychological assessment. And PCA patients showed more severe posterior atrophy and less severe left medial temporal lobe atrophy compared with TAD patients. The data from 11C-PIB PET scanning showed that amyloid beta deposition in PCA was comparable to TAD. Moreover, in PCA the results from 18F-FDG PET scanning revealed significant hypometabolism in the temporoparietooccipital region and identified specific hypometabolism in the right occipital lobe, compared with TAD. Our study thus provides a preliminary view of PCA in Chinese patients. A further study with a larger number of subjects would be recommended to confirm these findings. PMID:26267071

  1. Decrypting the Formation Conditions of the Basement Carbonate-Bearing Rocks at Nili Fossae

    NASA Astrophysics Data System (ADS)

    Brown, A. J.

    2015-12-01

    The Nili Fossae region is the site of a number of proposed Landing Sites for the Mars 2020 Rover. A distinguishing feature of many of these sites is the access to large exposures of carbonate (Ehlmann et al. 2008). Serpentinization has been proposed as a formation mechanism of these carbonates, including carbonated (Brown et al. 2010, Viviano, et al. 2013) and low temperature, near surface serpentinization. The potential for carbonated serpentization at Nili Fossae links the region to Earth analogs in terrestrial greenstone belts such as the Pilbara in Western Australia, where talc-carbonate bearing komatiite cumulate units of the Dresser Formation overlie the siliceous, stromatolite-bearing Strelley Pool Chert unit (Van Kranendonk and Pirajno, 2004). If a similar relationship exists on Mars, investigations of rocks stratigraphically beneath the carbonate-bearing units at Nili Fossae ("the basement rocks") may provide the best chance to examine well preserved organic material from the Noachian. This hypothesis is testable by Mars 2020. In preparation for the the Mars 2020 landing site, we are examining the thermodynamic relationships that favor formation of serpentine and talc-carbonate and different pressures and temperatures in the crust (Barnes 2007). This will allow us to constrain the low grade metamorphism required to replicate the proposed models of serpentinisation and help us understand the regional metamophic gradient that is critical to furthering our knowledge of the ancient rocks of Nili Fossae. Refs:Barnes, S. J. "Komatiites: Petrology, Volcanology, Metamorphism, and Geochemistry." S.E.G. 13 (2007): 13. Brown, A. J., et al.. "Hydrothermal Formation of Clay-Carbonate Alteration Assemblages in the Nili Fossae Region of Mars." EPSL 297 (2010): 174-82. Ehlmann, B. L. et al. "Orbital Identification of Carbonate-Bearing Rocks on Mars." Science 322, no. 5909 1828-32. Van Kranendonk, M.J., and F. Pirajno. "Geochemistry of Metabasalts and Hydrothermal

  2. Properties of the Medussae Fossae Formation and its relation to the volcanic history of Mars

    NASA Astrophysics Data System (ADS)

    Ivanov, Anton B.; Cantini, Federico

    2016-10-01

    Medussae Fossae (MFF) is a well known formation, stretching west of Tharsis volanoes. It is characterized as a relatively young Amazonian units (Amm, Amu), due to widespread signs of erosion. Earth based imaging radar observations at 3.5 cm [1] and 12 cm [2] have discovered a dark radar feature (Stealth), which roughly correlates with the MFF outline.Recent investigations [3], suggested that the unit emplacement is in fact during Hesperian period, but it is composed of material that can be easily eroded. It is not clear when the erosion happened and if it is a continuing process. Hypotheses on MFF formation range from volcanic material emplacement (ash flow tuffs or pyroclastic materials) to an ice-rich dusty mantle, deposited during high obliquity.In this work, we will present the latest observations of the East Medussae Fossae formation by the long wavelength MARSIS radar, continuing the work reported in [4], as well as complementing data surveyed by SHARAD data in [5]. The MARSIS radar has detected strong subsurface interfaces in the areas of Gordi and Eumenides Dorsae at depths up to 1.5km. We will present our analysis of the data, inferring the dielectric properties of the material to constrain properties of the material constituting the Medusae Fossae formation. We will also demonstrate an efficient user interface to work with MARSIS data inside a Geographical Information System (GIS).The research leading to these results has received funding from the European Unions Seventh Framework Programme (FP7/2007-2013) under iMars grant agreement 607379.[1] D. Muhleman, et al., "Radar images of mars," Science, vol. 253, no. 5027, 1991.[2] J. K. Harmon, et al., "Arecibo radar imagery of Mars: The major volcanic provinces," Icarus, vol. 220, aug 2012.[3] L. Kerber, et al., "The dispersal of pyroclasts from Apollinaris Patera, Mars: Implications for the origin of the Medusae Fossae Formation," Icarus, vol. 216, nov 2011.[4] T. R. Watters, et al., "Radar Sounding of the

  3. An Exploration Zone in Cerberus Containing Young and Old Terrains, Including Fossae/Faults and Shergottite Distal Ejecta

    NASA Astrophysics Data System (ADS)

    Wright, S. P.; Niles, P. B.; Bell, M. S.; Milbury, C.; Rice, J. W.; Burton, A. S.; Archer, P. D.; Rampe, E. B.; Piqueux, S.

    2015-10-01

    Cerberus contains Amazonian lava flows embaying a range of photogeologic units: ridged plains, heavily cratered terrain, highland knobs, and perhaps the Medusa Fossae Fm. Zunil Crater distal ejecta produced secondary crater fields (of shergottites?).

  4. Extreme redundancy of the valve of the fossa ovalis with right heart hypoplasia in a neonate with trisomy 18.

    PubMed

    Vyas, Himeshkumar; Cabalka, Allison K

    2006-10-01

    Infants with trisomy 18 often have important cardiovascular malformations. We describe an infant with trisomy 18 who had extreme redundancy of the flap valve of the fossa ovalis along with right heart hypoplasia.

  5. [Thyroid adenoma in the piriform fossa: a case report and literature review].

    PubMed

    Huang, X T; Ma, B; Liu, M B; Zhang, Y; Huang, D L; Chen, L

    2017-02-07

    Objective: To explore the clinical characteristics of case of thyroid adenoma in the piriform fossa, and review the literatures of the congentital thyroid gland abnormality. Methods: A 44-year-old male had foreign body feeling in his pharynx for 3 years. A mass in his left piriform fossa was detected by the clinical and imaging examination. Biopsy report that the mass was thyroid papillary carcinoma. The resection of tumor with partial back thyroid cartilage through lateral neck and pharyngeal approach was performed. Results: The surgical wound healed in first-stage and no any surgical complication occurred. With postoperative pathological and immunohistochemical examination, the mass was finally diagnosed as thyroid gland adenoma. Staining for cytokerantin19 was negative. Conclusion: The symptomatic and neoplastic abnormal thyroid gland should be excised, but asymptomtic, non-neoplastic and functional abnormal thyroid gland should be retained with regular follow up.

  6. The small saphenous vein and other 'neglected' veins of the popliteal fossa: a review.

    PubMed

    O'Donnell, T F; Iafrati, M D

    2007-01-01

    The small saphenous vein (SSV) and other veins in the popliteal fossa merit little discussion in the literature or in didactic programmes regarding their role in chronic venous insufficiency (CVI) and, in this sense, they are neglected. The purpose of this review is to present both duplex ultrasound findings and the associated clinical characteristics of patients with SSV reflux, from several large series. Both the anatomic variations and the epidemiology of the SSV, as well as other veins of the popliteal fossa, the gastrocnemius veins, Gocamini vein, popliteal area veins and popliteal vein, will be discussed. Findings from our review of the current available literature will demonstrate the important role that these veins play in association with CVI. The implications for open and endovenous surgery will be underlined.

  7. Effects of friction massage of the popliteal fossa on blood flow velocity of the popliteal vein

    PubMed Central

    Iwamoto, Koji; Mizukami, Masafumi; Asakawa, Yasutsugu; Endo, Yusuke; Takata, Yuichi; Yoshikawa, Kenichi; Yoshio, Masaharu

    2017-01-01

    [Purpose] Friction massage (friction) of the popliteal fossa is provided for the purpose of relieving pain related to circulatory disorders by improving venous flow in the lower legs. The purpose of this study is to verify the effects of enhancing the venous flow based on measuring the blood flow velocity of the popliteal vein before and after providing friction to the patients. [Subjects and Methods] Fifteen healthy male university students participated in the study. The Doppler ultrasonography (DU) was used to measure the blood flow velocity of the popliteal vein, in order to verify the effects of enhancing the venous flow by comparing the measured values before and after a friction massage. [Results] The result of comparing the blood flow velocity before and after providing friction showed that there was a significant increase after friction. [Conclusion] This study proved that friction to the popliteal fossa is effectively enhances venous flow by increasing the blood flow velocity in the popliteal vein. PMID:28356643

  8. An Inflammatory Pseudotumor Arising from Pterygopalatine Fossa with Invasion to the Maxillary Sinus and Orbital Cavity

    PubMed Central

    Yokoi, Hidenori; Yazawa, Takuya; Matsumoto, Yuma; Ikeda, Tetsuya; Fujiwara, Masachika; Ohkura, Yasuo; Kohno, Naoyuki

    2015-01-01

    We report a patient who had an inflammatory pseudotumor (IPT) that invaded to the maxillary sinus and orbital cavity, with the left pterygopalatine fossa as the principal site; this is a very rare case. The patient was an 83-year-old woman who suddenly became aware of impairment in the eyesight and visual field of the left eye. CT images showed a neoplastic lesion that invaded to the maxillary sinus and orbital cavity, with the left pterygopalatine fossa as the principal site, and also showed contrast effects. To obtain a definitive diagnosis from histopathological analysis, the lesion was biopsied, and she was diagnosed as the inflammatory pseudotumor with the immunohistochemical study and multiplex polymerase chain reaction-based clonality assays. The patient had a lymphoid-predominant lesion that responded to radiotherapy but corticosteroids were not effective. It is important to scrutinize the pathology to avoid unnecessary and mutilating surgery. PMID:26167321

  9. Clinical studies of photodynamic therapy for malignant brain tumors: facial nerve palsy after temporal fossa photoillumination

    NASA Astrophysics Data System (ADS)

    Muller, Paul J.; Wilson, Brian C.; Lilge, Lothar D.; Varma, Abhay; Bogaards, Arjen; Fullagar, Tim; Fenstermaker, Robert; Selker, Robert; Abrams, Judith

    2003-06-01

    In two randomized prospective studies of brain tumor PDT more than 180 patients have been accrued. At the Toronto site we recognized two patients who developed a lower motor neuron (LMN) facial paralysis in the week following the PDT treatment. In both cases a temporal lobectomy was undertaken and the residual tumor cavity was photo-illuminated. The surface illuminated included the temporal fossa floor, thus potentially exposing the facial nerve to the effect of PDT. The number of frontal, temporal, parietal, and occipital tumors in this cohort was 39, 24, 12 and 4, respectively. Of the 24 temporal tumors 18 were randomized to Photofrin-PDT. Of these 18 a temporal lobectomy was carried out exposing the middle fossa floor as part of the tumor resection. In two of the 10 patients where the lobectomy was carried out and the fossa floor was exposed to light there occurred a postoperative facial palsy. Both patients recovered facial nerve function in 6 and 12 weeks, respectively. 46 J/cm2 were used in the former and 130 J/cm2 in the latter. We did not encounter a single post-operative LMN facial plasy in the 101 phase 2 patients treated with Photofrin-PDT. Among 688 supratentorial brain tumor operations in the last decade involving all pathologies and all locations no case of early post-operative LMN facial palsy was identified in the absence of PDT. One further patient who had a with post-PDT facial palsy was identified at the Denver site. Although it is possible that these patients had incidental Bell's palsy, we now recommend shielding the temporal fossa floor during PDT.

  10. Unilateral renal agenesis and other causes of the solitary photopenic renal fossa

    SciTech Connect

    Howard, W.H.; Bunker, S.R.; Karl, R.D. Jr.; Ralston, T.; Hartshorne, M.F.; Cawthon, M.A.; Bauman, J.M.

    1985-04-01

    The differential diagnosis of a solitary photopenic defect in the renal fossa observed at renal scintigraphy is extensive. A case of one of the most unusual causes for this finding, renal agenesis, is presented. Additional cases that illustrate the similarity in the radionuclide appearance of other pathologic entities are also presented. Correlation with clinical findings and other imaging modalities is required to accurately distinguish these conditions.

  11. Geologic Mapping of the Medusae Fossae Formation, Mars, and the Northern Lowland Plains, Venus

    NASA Technical Reports Server (NTRS)

    Zimbelman, J. R.

    2010-01-01

    This report summarizes the status of mapping projects supported by NASA grant NNX07AP42G, through the Planetary Geology and Geophysics (PGG) program. The PGG grant is focused on 1:2M-scale mapping of portions of the Medusae Fossae Formation (MFF) on Mars. Also described below is the current status of two Venus geologic maps, generated under an earlier PGG mapping grant.

  12. Geologic Mapping of the Medusae Fossae Formation on Mars and the Northern Lowland Plains of Venus

    NASA Technical Reports Server (NTRS)

    Zimbelman, J. R.

    2009-01-01

    This report summarizes the status of mapping projects supported by NASA grant NNX07AP42G, through the Planetary Geology and Geophysics (PGG) program. The PGG grant is focused on 1:2M-scale mapping of portions of the Medusae Fossae Formation (MFF) on Mars. Also described below is the current status of two Venus geo-logic maps, generated under an earlier PGG mapping grant.

  13. The supraclavicular fossa ultrasound view for central venous catheter placement and catheter change over guidewire.

    PubMed

    Kim, Se-Chan; Klebach, Christian; Heinze, Ingo; Hoeft, Andreas; Baumgarten, Georg; Weber, Stefan

    2014-12-23

    The supraclavicular fossa ultrasound view can be useful for central venous catheter (CVC) placement. Venipuncture of the internal jugular veins (IJV) or subclavian veins is performed with a micro-convex ultrasound probe, using a neonatal abdominal preset with a probe frequency of 10 Mhz at a depth of 10-12 cm. Following insertion of the guidewire into the vein, the probe is shifted to the right supraclavicular fossa to obtain a view of the superior vena cava (SVC), right pulmonary artery and ascending aorta. Under real-time ultrasound view, the guidewire and its J-tip is visualized and pushed forward to the lower SVC. Insertion depth is read from guidewire marks using central venous catheter. CVC is then inserted following skin and venous dilation. The supraclavicular fossa view is most suitable for right IJV CVC insertion. If other insertion sites are chosen the right supraclavicular fossa should be within the sterile field. Scanning of the IJVs, brachiocephalic veins and SVC can reveal significant thrombosis before venipuncture. Misplaced CVCs can be corrected with a change over guidewire technique under real-time ultrasound guidance. In conjunction with a diagnostic lung ultrasound scan, this technique has a potential to replace chest radiograph for confirmation of CVC tip position and exclusion of pneumothorax. Moreover, this view is of advantage in patients with a non-p-wave cardiac rhythm were an intra-cardiac electrocardiography (ECG) is not feasible for CVC tip position confirmation. Limitations of the method are lack of availability of a micro-convex probe and the need for training.

  14. A Nomenclature for Vertebral Fossae in Sauropods and Other Saurischian Dinosaurs

    PubMed Central

    Wilson, Jeffrey A.; D'Emic, Michael D.; Ikejiri, Takehito; Moacdieh, Emile M.; Whitlock, John A.

    2011-01-01

    Background The axial skeleton of extinct saurischian dinosaurs (i.e., theropods, sauropodomorphs), like living birds, was pneumatized by epithelial outpocketings of the respiratory system. Pneumatic signatures in the vertebral column of fossil saurischians include complex branching chambers within the bone (internal pneumaticity) and large chambers visible externally that are bounded by neural arch laminae (external pneumaticity). Although general aspects of internal pneumaticity are synapomorphic for saurischian subgroups, the individual internal pneumatic spaces cannot be homologized across species or even along the vertebral column, due to their variability and absence of topographical landmarks. External pneumatic structures, in contrast, are defined by ready topological landmarks (vertebral laminae), but no consistent nomenclatural system exists. This deficiency has fostered confusion and limited their use as character data in phylogenetic analysis. Methodology/Principal Findings We present a simple system for naming external neural arch fossae that parallels the one developed for the vertebral laminae that bound them. The nomenclatural system identifies fossae by pointing to reference landmarks (e.g., neural spine, centrum, costal articulations, zygapophyses). We standardize the naming process by creating tripartite names from “primary landmarks,” which form the zygodiapophyseal table, “secondary landmarks,” which orient with respect to that table, and “tertiary landmarks,” which further delineate a given fossa. Conclusions/Significance The proposed nomenclatural system for lamina-bounded fossae adds clarity to descriptions of complex vertebrae and allows these structures to be sourced as character data for phylogenetic analyses. These anatomical terms denote potentially homologous pneumatic structures within Saurischia, but they could be applied to any vertebrate with vertebral laminae that enclose spaces, regardless of their developmental origin

  15. A (comparative study on the nasal fossae of Tupaia glis and four insectivores.

    PubMed

    Woehrmann-Repenning, A; Meinel, W

    1977-01-01

    The macro- and microscopic anatomy of the nasal fossa of Tupaia glis was compared with those of some insectivores. No significant group differences were found as far as the intranasal structures are concerned. Since the number of receptor cells in the olfactory epithelium of Tupaia glis and Talpa europaea is smaller than in the other species studied, a slight reduction of the sense of smell is suggested.

  16. Cochlear Implantation through the Middle Fossa Approach: A Review of Related Temporal Bone Studies and Reported Cases

    PubMed Central

    Lesser, Juan Carlos Cisneros; Brito Neto, Rubens Vuono de; Martins, Graziela de Souza Queiroz; Bento, Ricardo Ferreira

    2016-01-01

    Introduction Middle fossa approach has been suggested as an alternative for patients in whom other routes of electrode insertion are contraindicated. Even though there are temporal bone studies about the feasibility of introducing the cochlear implant through the middle fossa, until now, very few studies have described results when cochlear implant surgery is done through this approach. Objective The objective of this study is to review a series of temporal bone studies related to cochlear implantation through the middle fossa and the results obtained by different surgical groups after cochlear implantation through this approach. Data Sources PubMed, MD consult and Ovid-SP databases. Data Synthesis A total of 8 human cadaveric temporal bone studies and 6 studies reporting cochlear implant surgery through the middle fossa approach met the inclusion criteria. Temporal bone studies show that it is feasible to perform cochlear implantation through this route. So far, only two surgical groups have performed cochlear implantation through the middle fossa with a total of 15 implanted patients. One group entered the cochlea in the most upper part of the basal turn, inserting the implant in the direction of the middle and apical turns; meanwhile, the other group inserted the implant in the apical turn directed in a retrograde fashion to the middle and basal turns. Results obtained in both groups were similar. Conclusions The middle fossa approach is a good alternative for cochlear implantation when other routes of electrode insertion are contraindicated. PMID:28050216

  17. Cochlear Implantation through the Middle Fossa Approach: A Review of Related Temporal Bone Studies and Reported Cases.

    PubMed

    Lesser, Juan Carlos Cisneros; Brito Neto, Rubens Vuono de; Martins, Graziela de Souza Queiroz; Bento, Ricardo Ferreira

    2017-01-01

    Introduction Middle fossa approach has been suggested as an alternative for patients in whom other routes of electrode insertion are contraindicated. Even though there are temporal bone studies about the feasibility of introducing the cochlear implant through the middle fossa, until now, very few studies have described results when cochlear implant surgery is done through this approach. Objective The objective of this study is to review a series of temporal bone studies related to cochlear implantation through the middle fossa and the results obtained by different surgical groups after cochlear implantation through this approach. Data Sources PubMed, MD consult and Ovid-SP databases. Data Synthesis A total of 8 human cadaveric temporal bone studies and 6 studies reporting cochlear implant surgery through the middle fossa approach met the inclusion criteria. Temporal bone studies show that it is feasible to perform cochlear implantation through this route. So far, only two surgical groups have performed cochlear implantation through the middle fossa with a total of 15 implanted patients. One group entered the cochlea in the most upper part of the basal turn, inserting the implant in the direction of the middle and apical turns; meanwhile, the other group inserted the implant in the apical turn directed in a retrograde fashion to the middle and basal turns. Results obtained in both groups were similar. Conclusions The middle fossa approach is a good alternative for cochlear implantation when other routes of electrode insertion are contraindicated.

  18. Temporal fossa defects: techniques for injecting hyaluronic acid filler and complications after hyaluronic acid filler injection.

    PubMed

    Juhász, Margit Lai Wun; Marmur, Ellen S

    2015-09-01

    Facial changes with aging include thinning of the epidermis, loss of skin elasticity, atrophy of muscle, and subcutaneous fat and bony changes, all which result in a loss of volume. As temporal bones become more concave, and the temporalis atrophies and the temporal fat pad decreases, volume loss leads to an undesirable, gaunt appearance. By altering the temporal fossa and upper face with hyaluronic acid filler, those whose specialty is injecting filler can achieve a balanced and more youthful facial structure. Many techniques have been described to inject filler into the fossa including a "fanned" pattern of injections, highly diluted filler injection, and the method we describe using a three-injection approach. Complications of filler in the temporal fossa include bruising, tenderness, swelling, Tyndall effect, overcorrection, and chewing discomfort. Although rare, more serious complications include infection, foreign body granuloma, intravascular necrosis, and blindness due to embolization into the ophthalmic artery. Using reversible hyaluronic acid fillers, hyaluronidase can be used to relieve any discomfort felt by the patient. Injectors must be aware of the complications that may occur and provide treatment readily to avoid morbidities associated with filler injection into this sensitive area.

  19. Infratemporal fossa cellulitis caused by a remnant iatrogenic foreign body after a bimaxillary operation.

    PubMed

    Park, Do Yang; Choo, Oak-Sung; Hong, Sang Young; Kim, Hyun Jun

    2015-05-01

    Infratemporal fossa cellulitis is rare and mostly occurs because of sinusitis and dental procedures. Furthermore, cellulitis caused by iatrogenic foreign bodies is very rare. A 28-year-old woman who had previously undergone cosmetic bimaxillary operation visited our hospital complaining of left facial swelling, oppressive pain, and nasal obstruction since 2 years. She had been attending another clinic, but despite having additional procedures and taking medications, her symptoms persisted. A subsequent operation was performed, during which we found a remnant surgical gauze from the previous operation, which was decomposed and trapped around the necrotic soft tissue and had eroded the bony structure around the pterygoid fossa. The material was successfully removed by endoscopic surgery, and the necrotic tissue was debrided. After the operation, all symptoms disappeared, and the patient was discharged without sequelae. During any procedure, surgeons must meticulously check for remnant material. Additionally, physicians must carefully note patient history and perform a physical examination, even in patients without serious symptoms. We report a case of advanced infratemporal fossa cellulitis due to remnant gauze material during a previous operation that was undetected.

  20. [Linear accelerator-based stereotactic radiation treatment of patients with medial middle fossa meningiomas].

    PubMed

    Golanov, A V; Cherekaev, V A; Serova, N K; Pronin, I N; Gorlachev, G E; Kotel'nikova, T M; Podoprigora, A E; Kudriavtseva, P A; Galkin, M V

    2010-01-01

    Medial middle fossa meningiomas are challenging for neurosurgical treatment. Invasion of cranial nerves and vessels leads to high risk of complications after removal of such meningiomas. Currently methods of conformal stereotactic radiation treatment are applied wider and wider for the discussed lesions. During a 3.5-year period 80 patients with medial middle fossa meningiomas were treated in Burdenko Moscow Neurosurgical Institute using linear accelerator "Novalis". In 31 case radiation treatment was preceded by surgical resection. In majority of patients symptoms included cranial nerve dysfunction: oculomotor disturbances in 62.5%, trigeminal impairment--in 37.5%, visual deficit--in 43.8%, facial nerve palsy--in 1.25%. 74 patients underwent radiotherapy with classical fractioning, 2--in hypofractionated mode and 4 received radiosurgery. In cases of classical fractioning mean marginal dose reached 46.3 Gy during 28-33 fractions, in hypofractioning (7 fractions)--31.5 Gy, in radiosurgery--16.25 Gy. Mean follow-up period was 18.4 months (6-42 months). Control of tumor growth was achieved in 97.5% of cases (78 patients): in 42 (52.5%) lesion shrinked, in 36 (45%) stabilization was observed. Clinical examination revealed improvement of visual function in 15 patients (18%) and deterioration in 2 (2.5%). No new neuropathies were found. Stereotactic radiation treatment is the method of choice for medial anterior and middle fossa meningiomas due to effective control of tumor progression and minimal rate of complications.

  1. Rethinking "posterior" tongue-tie.

    PubMed

    Douglas, Pamela Sylvia

    2013-12-01

    Currently, many clinicians who help with breastfeeding problems are diagnosing "posterior" tongue-tie in infants and performing or referring for frenotomy. In this "Speaking Out" article, I argue that the diagnosis of "posterior" tongue-tie has successfully raised awareness of the importance of impaired tongue function in breastfeeding difficulty. However, the diagnosis of "posterior" tongue-tie also applies a reductionist, medicalized theoretical frame to the complex problem of impaired tongue function, risking unintended outcomes. Impaired tongue function arises out of multiple interacting and co-evolving factors, including the interplay between social behaviors concerning breastfeeding and mother-infant biology. Consideration of theoretical frames is vital if we are to build an evidence base through efficient use of the scarce resources available for clinical breastfeeding research and minimize unintended outcomes.

  2. Scene perception in posterior cortical atrophy: categorization, description and fixation patterns

    PubMed Central

    Shakespeare, Timothy J.; Yong, Keir X. X.; Frost, Chris; Kim, Lois G.; Warrington, Elizabeth K.; Crutch, Sebastian J.

    2013-01-01

    Partial or complete Balint's syndrome is a core feature of the clinico-radiological syndrome of posterior cortical atrophy (PCA), in which individuals experience a progressive deterioration of cortical vision. Although multi-object arrays are frequently used to detect simultanagnosia in the clinical assessment and diagnosis of PCA, to date there have been no group studies of scene perception in patients with the syndrome. The current study involved three linked experiments conducted in PCA patients and healthy controls. Experiment 1 evaluated the accuracy and latency of complex scene perception relative to individual faces and objects (color and grayscale) using a categorization paradigm. PCA patients were both less accurate (faces < scenes < objects) and slower (scenes < objects < faces) than controls on all categories, with performance strongly associated with their level of basic visual processing impairment; patients also showed a small advantage for color over grayscale stimuli. Experiment 2 involved free description of real world scenes. PCA patients generated fewer features and more misperceptions than controls, though perceptual errors were always consistent with the patient's global understanding of the scene (whether correct or not). Experiment 3 used eye tracking measures to compare patient and control eye movements over initial and subsequent fixations of scenes. Patients' fixation patterns were significantly different to those of young and age-matched controls, with comparable group differences for both initial and subsequent fixations. Overall, these findings describe the variability in everyday scene perception exhibited by individuals with PCA, and indicate the importance of exposure duration in the perception of complex scenes. PMID:24106469

  3. Endoscopic ligation of the internal maxillary artery for treatment of intractable posterior epistaxis.

    PubMed

    Pritikin, J B; Caldarelli, D D; Panje, W R

    1998-02-01

    Lack of universal success with both transantral ligation of the internal maxillary artery and percutaneous embolization of the distal branches of the internal maxillary distribution has led to consideration of alternative techniques to control intractable posterior epistaxis. One such technique takes advantage of advances in endoscopic technology and instrumentation, as well as a nearly constant anatomic configuration. The internal maxillary artery divides into terminal branches within the pterygomaxillary fossa, sending branches through the bony maxilla to exit the posterolateral nasal wall in the posterior aspect of the middle meatus. Endoscopic identification and ligation of these terminal branches of the internal maxillary artery (the sphenopalatine and nasopalatine arteries) as they exit the maxilla has been performed on 10 patients with a 100% success rate and no morbidity or mortality associated with the procedure. These results compare favorably to the average reported success rates of 89% for transantral ligation and 94% for percutaneous embolization, and average complication rates of 28% and 27%, respectively. This endonasal procedure has been performed for spontaneous epistaxis as well as postsurgical nasal bleeding with equal success. The ascending scale of treatment previously outlined in the literature may be amended, as a potentially definitive procedure is available, and we believe that this technique is easier to perform, has less associated morbidity, and has equal efficacy in comparison to transantral ligation or percutaneous embolization in the treatment of intractable posterior epistaxis.

  4. Integrated Anterior, Central, and Posterior Skull Base Unit – A New Perspective

    PubMed Central

    Brand, Yves; Waran, Vicknes; Zulkiflee, Abu Bakar; Lim, Elizabeth; Prepageran, Narayanan

    2015-01-01

    The skull base is one of the most complex anatomical regions and forms the floor of the cranial cavity. Skull base surgery involves open, microscopic, and endoscopic approaches to the anterior, middle, or posterior cranial fossa. A multispecialty team approach is essential in treating patients with skull base lesions. Traditionally, rhinologists are involved in providing access to anterior skull base lesions while otologists are involved in the treatment of lesions of the posterior skull base. This is the case in most skull base centers today. In this article, we share a new perspective of an integrated skull base unit where a team of otolaryngologists and neurosurgeons treat anterior, middle, and posterior skull base pathologies. The rationale for this approach is that most technical skills required in skull base surgery are interchangeable and apply whether an endoscopic or microscopic approach is used. We show how the different skills apply to the different approaches and share our experience with an integrated skull base unit. PMID:26258128

  5. Children's Understanding of Posterior Probability

    ERIC Educational Resources Information Center

    Girotto, Vittorio; Gonzalez, Michael

    2008-01-01

    Do young children have a basic intuition of posterior probability? Do they update their decisions and judgments in the light of new evidence? We hypothesized that they can do so extensionally, by considering and counting the various ways in which an event may or may not occur. The results reported in this paper showed that from the age of five,…

  6. Clinico-radiological profile and outcome of dengue patients with central nervous system manifestations: A case series in an Eastern India tertiary care hospital

    PubMed Central

    Pal, Souren; Sen, Kaushik; Biswas, Nirendra Mohan; Ghosal, Anirban; Rousan Jaman, S. K.; Yashavantha Kumar, K. Y.

    2016-01-01

    Background and Objective: Dengue, an acute viral disease, transmitted by Aedes mosquitoes, has a variable clinical spectrum ranging from asymptomatic infection to life-threatening dengue hemorrhagic fever and dengue shock syndrome. However, neurological complications, in general, are unusual but have been observed more frequently in the recent past, and some studies highlighted varied neurological complications during the course of illness. Although dengue is classically considered a nonneurotropic virus, there is increasing evidence for dengue viral neurotropism. In this study, we have evaluated clinico-radiological profile and outcome of nine serologically confirmed dengue patients having varied manifestations of central nervous system (CNS) involvement. Materials and Methods: All the consecutive patients presented with neurological complications with positive serology for dengue infection (IgM positivity) in Department of Medicine, in a tertiary care hospital in Eastern India from August 2013 to October 2014 were included in the study. These patients were subjected to a detailed clinical evaluation, laboratory assessment including complete hemogram, coagulation profile, liver function test, serum electrolytes, and routine CSF (Cerebrospinal Fluid) study with the exclusion of other common neuroinvasive pathogens. Results: Out of 9 patients with neurological complications associated with confirmed dengue infection, 2 (22%) patients had dengue encephalopathy, 5 (56%) patients have dengue encephalitis, 1 (11%) patient had dengue meningitis, and 1 (11%) patient had postdengue immune-mediated CNS involvement. Conclusion: This case series reaffirms the occurrence of varied CNS manifestations in dengue virus infection and underlines the importance of inclusion of dengue in the differential diagnosis of acute encephalitis syndrome. PMID:26933357

  7. Anatomy of greater palatine foramen and canal and pterygopalatine fossa in Thais: considerations for maxillary nerve block.

    PubMed

    Methathrathip, D; Apinhasmit, W; Chompoopong, S; Lertsirithong, A; Ariyawatkul, T; Sangvichien, S

    2005-12-01

    This study aims to investigate the anatomy of the greater palatine foramen (GPF), greater palatine canal (GPC) and pterygopalatine fossa (PPF) with special reference to the blockage of the maxillary nerve. A correlation between the length of GPC and PPF and the heights of the orbit and the maxilla was also studied using simple linear regression analysis. The morphology of the GPF, GPC and PPF as well as heights of the orbit and the maxilla were assessed in 105 Thai skulls. The thickness of the mucosa over the GPF was also measured from the dissection of 55 cadavers. The results showed that most GPF appeared as an oval foramen located at the palatal aspect of the upper third molar. The GPF was 16.2+/-1.3 mm lateral to the median sagittal plane of the hard palate, 2.1+/-1.3 mm anterior to the posterior border of the hard palate and 5.1+/-1.3 mm from the greatest concavity of the distolateral margin of the hard palate. The mean length of GPC and PPF was 29.7+/-4.2 mm. The mean angles of the GPC in relation to the hard palate and the vertical plane were 57.9+/-5.8 degrees and 6.7+/-5.2 degrees , respectively. In attempting to insert a needle to reach the foramen rotundum through the GPF, 31.7% passed into the orbit while 8.7% passed into the brain. The mean thickness of the mucosa over GPF was 6.7+/-2.3 mm. Two models for estimating the depth of needle injection in maxillary nerve block have been developed as follows: Length of GPC and PPF=19.038+0.314 (orbital height) and length of GPC and PPF=21.204+0.187 (maxillary height). The calculated length combined with the mucosal thickness was the estimated depth of needle injection. In conclusion, our results concerning the GPF, GPC and PPF will provide the useful reference for clinicians to anesthetize the maxillary nerve with a greater degree of success.

  8. Regional brain volumes distinguish PSP, MSA-P, and PD: MRI-based clinico-radiological correlations.

    PubMed

    Paviour, Dominic C; Price, Shona L; Jahanshahi, Marjan; Lees, Andrew J; Fox, Nick C

    2006-07-01

    Progressive supranuclear palsy (PSP) and multiple system atrophy (MSA) are neurodegenerative disorders, each with a prevalence of around 5 per 100,000. Regional brain atrophy patterns differ in the two disorders, however, and magnetic resonance imaging is sometimes helpful in distinguishing them in the later stages. We measured whole brain and regional volumes, including cerebellum, pons, midbrain, superior cerebellar peduncle (SCP), and ventricular volumes as well as frontal and posterior-inferior cerebral regions in 18 subjects with PSP, 9 with MSA-P (parkinsonian phenotype), 9 with Parkinson's disease (PD), and 18 healthy controls. Associations between these volumes, cognitive profiles, and clinical measures of disease severity and motor disability were assessed. Mean midbrain volume was 30% smaller in PSP than in PD or controls (P < 0.001) and 15% smaller than in MSA-P (P = 0.009). The mean SCP volume in PSP was 30% smaller than in MSA-P, PD, or controls (P < 0.001). Mean cerebellar volumes in MSA-P were 20% smaller than in controls and PD and 18% smaller than in PSP (P = 0.01). Mean pontine volume in MSA-P was 30% smaller than in PD or controls (P < 0.001) and 25% smaller than in PSP (P = 0.01). Motor disability was most strongly associated with midbrain volume, and more severe executive dysfunction was associated with reduced frontal volume. These distinct patterns of cortical and subcortical atrophy, when considered together rather than independently, better differentiate PSP and MSA-P from each other and also from healthy controls.

  9. Distortions of posterior visual space.

    PubMed

    Phillips, Flip; Voshell, Martin G

    2009-01-01

    The study of spatial vision is a long and well traveled road (which, of course, converges to a vanishing point at the horizon). Its various distortions have been widely investigated empirically, and most concentrate, pragmatically, on the space anterior to the observer. The visual world behind the observer has received relatively less attention and it is this perspective the current experiments address. Our results show systematic perceptual distortions in the posterior visual world when viewed statically. Under static viewing conditions, observer's perceptual representation was consistently 'spread' in a hyperbolic fashion. Directions to distant, peripheral locations were consistently overestimated by about 11 degrees from the ground truth and this variability increased as the target was moved toward the center of the observer's back. The perceptual representation of posterior visual space is, no doubt, secondary to the more immediate needs of the anterior visual world. Still, it is important in some domains including certain sports, such as rowing, and in vehicular navigation.

  10. Usefulness of laboratory data in the management of right iliac fossa pain in adults

    PubMed Central

    Ortega-Deballon, Pablo; Ruiz De Adana-Belbel, Juan C; Hernández-Matías, Alberto; García-Septiem, Javier; Moreno-Azcoita, Mariano

    2008-01-01

    Background Inflammatory markers could be helpful in the management of patients with right iliac fossa pain, but the heterogeneity of designs and results precludes a definitive conclusion. A retrospective analysis of prospectively collected data was performed to assess the usefulness of laboratory data in the management of these patients. Patients and methods Patients with right iliac fossa pain referred to the surgeon were included. Blood samples were obtained for C-reactive protein, leukocyte, and granulocyte analysis. Clinical, surgical, and histopathologic data were collected. Analysis of inflammatory parameters was performed with logistic regression and areas under the receiver operating characteristic curve were compared. Results One hundred thirty-four patients were included. C-reactive protein increased with the severity of appendicitis and predicted accurately perforation (r2 = 0.613; P < 0.0005), showing the highest accuracy among inflammatory markers (areas under the ROC curve were 0.846, 0.753 and 0.685 for C-reactive protein, leukocyte and granulocytes, respectively; P < 0.001). Accuracy improved when C-reactive protein and leukocytes were combined (positive and negative predictive values were 93.2 percent and 92.3 percent, respectively). Conclusions C-reactive protein is a helpful marker in the management of patients with right iliac fossa pain. It increases with the evolution of the inflammatory process. Its predictive values improve in combination with the leukocyte count. A patient with normal C-reactive protein and leukocytes has a very low probability of appendicitis and should not undergo surgery. PMID:18484138

  11. Condyle-fossa modifications and muscle interactions during herbst treatment, part 1. New technological methods.

    PubMed

    Voudouris, John C; Woodside, Donald G; Altuna, Gurkan; Kuftinec, Mladen M; Angelopoulos, Gerassimos; Bourque, Paul J

    2003-06-01

    Changes in the condyle, the glenoid fossa, and the muscles of mastication were investigated in subjects undergoing continuous orthopedic advancement of the mandible with a Herbst-block appliance. The total sample consisted of 56 subjects and included 15 nonhuman primates (in the middle mixed, early permanent, and permanent dentitions), 17 human Herbst patients in the early permanent dentition, and 24 human controls from the Burlington Growth Center. The 8 nonhuman primates in the middle mixed dentition were the focus of this study. Mandibular advancement was obtained progressively in 5 animals by adding stops to the telescopic arms of fixed functional Herbst appliances with occlusal coverage; activations of 5.0 mm, 7.0 mm, and 8.0 mm were achieved. Two primates served as controls, and the third was a sham control. Two experimental animals and the 2 controls also wore surgically implanted electromyographic electrodes in the superior and inferior heads of the lateral pterygoid muscles and in the superficial masseter and anterior digastric muscles. Changes in condylar growth direction and amount were assessed with the Björk method from measurements made on serial cephalometric tracings superimposed on metallic implants. Undecalcified sections, treated with intravenous tetracycline vital staining, were viewed with fluorescence microscopy to examine histologic changes in the condyle and the glenoid fossa. New bone formation in the fossa associated with continuous mandibular protrusion was quantified by using computerized histomorphometric analysis of decalcified histological sections and polarized light. The unique combination of permanently implanted electromyographic electrodes, tetracycline vital staining, and histomorphometry represents a significant technological advancement in methods and materials. Together, they demonstrated different muscle-bone interaction results for functional appliances than those reported in previous studies. In Part 1 of this study, we

  12. Evidence for an additional uppermost geological unit in the Medusae Fossae Formation, Equatorial Mars

    NASA Astrophysics Data System (ADS)

    Harrison, Samantha; Balme, Matt; Hagermann, Axel

    2013-04-01

    The Medusae Fossae Formation (MFF) is a geological formation comprising three geological units (members) spread across five principal outcrops. The MFF dominates roughly a quarter of the longitudinal extent of the equatorial region of Mars, extending east-west across a distance of ~ 5,500 km between the southern Elysium Planitia and the Tharsis region. The nature of these materials is often referred to as enigmatic, as their exact origin remains unknown. Harrison et al. (Icarus, 2010) presented new observations of outlying occurrences of MFF materials on the southern highlands, atop the dichotomy boundary. They presented two hypotheses to explain these observation: 1) the MFF had a much larger pre-erosional extent than previously thought or 2) these materials had initially been eroded from the main outcrops of the formation, then transported southward by wind and subsequently reworked. A subsequent extension of this work provided evidence for an even larger extent of outlying MFF materials, particularly around and south of the easternmost portions of the MFF. Here we present these new outlier data, together with new textural classification and facies mapping of this region of the MFF. These data show that MFF outlier textures, whilst external to the main MFF outcrops in many places, are also found superposing large areas of the "main" MFF formations. These data support the first of the two working hypotheses presented, but also suggest that these so-called outlying materials represent a previously unmapped, stratigraphically uppermost unit of the Medusae Fossae Formation. We also suggest that, based upon our own morphometric study of yardangs across members and analogue studies by de Silva et al. (Icarus, 2010), these represent a less indurated material than other units of the formation. In the overall context of the origins of the MFF, we find that our data are consistent with the Medusae Fossae materials being a large-scale ignimbrite complex, perhaps with

  13. Avian Cerebellar Floccular Fossa Size Is Not a Proxy for Flying Ability in Birds

    PubMed Central

    Walsh, Stig A.; Iwaniuk, Andrew N.; Knoll, Monja A.; Bourdon, Estelle; Barrett, Paul M.; Milner, Angela C.; Nudds, Robert L.; Abel, Richard L.; Sterpaio, Patricia Dello

    2013-01-01

    Extinct animal behavior has often been inferred from qualitative assessments of relative brain region size in fossil endocranial casts. For instance, flight capability in pterosaurs and early birds has been inferred from the relative size of the cerebellar flocculus, which in life protrudes from the lateral surface of the cerebellum. A primary role of the flocculus is to integrate sensory information about head rotation and translation to stabilize visual gaze via the vestibulo-occular reflex (VOR). Because gaze stabilization is a critical aspect of flight, some authors have suggested that the flocculus is enlarged in flying species. Whether this can be further extended to a floccular expansion in highly maneuverable flying species or floccular reduction in flightless species is unknown. Here, we used micro computed-tomography to reconstruct “virtual” endocranial casts of 60 extant bird species, to extract the same level of anatomical information offered by fossils. Volumes of the floccular fossa and entire brain cavity were measured and these values correlated with four indices of flying behavior. Although a weak positive relationship was found between floccular fossa size and brachial index, no significant relationship was found between floccular fossa size and any other flight mode classification. These findings could be the result of the bony endocranium inaccurately reflecting the size of the neural flocculus, but might also reflect the importance of the flocculus for all modes of locomotion in birds. We therefore conclude that the relative size of the flocculus of endocranial casts is an unreliable predictor of locomotor behavior in extinct birds, and probably also pterosaurs and non-avian dinosaurs. PMID:23825638

  14. Avian cerebellar floccular fossa size is not a proxy for flying ability in birds.

    PubMed

    Walsh, Stig A; Iwaniuk, Andrew N; Knoll, Monja A; Bourdon, Estelle; Barrett, Paul M; Milner, Angela C; Nudds, Robert L; Abel, Richard L; Sterpaio, Patricia Dello

    2013-01-01

    Extinct animal behavior has often been inferred from qualitative assessments of relative brain region size in fossil endocranial casts. For instance, flight capability in pterosaurs and early birds has been inferred from the relative size of the cerebellar flocculus, which in life protrudes from the lateral surface of the cerebellum. A primary role of the flocculus is to integrate sensory information about head rotation and translation to stabilize visual gaze via the vestibulo-occular reflex (VOR). Because gaze stabilization is a critical aspect of flight, some authors have suggested that the flocculus is enlarged in flying species. Whether this can be further extended to a floccular expansion in highly maneuverable flying species or floccular reduction in flightless species is unknown. Here, we used micro computed-tomography to reconstruct "virtual" endocranial casts of 60 extant bird species, to extract the same level of anatomical information offered by fossils. Volumes of the floccular fossa and entire brain cavity were measured and these values correlated with four indices of flying behavior. Although a weak positive relationship was found between floccular fossa size and brachial index, no significant relationship was found between floccular fossa size and any other flight mode classification. These findings could be the result of the bony endocranium inaccurately reflecting the size of the neural flocculus, but might also reflect the importance of the flocculus for all modes of locomotion in birds. We therefore conclude that the relative size of the flocculus of endocranial casts is an unreliable predictor of locomotor behavior in extinct birds, and probably also pterosaurs and non-avian dinosaurs.

  15. Solitary Fibrous Tumor in the Lacrimal Gland Fossa: A Case Report

    PubMed Central

    Mupas-Uy, Jacqueline; Kitaguchi, Yoshiyuki; Takahashi, Yasuhiro; Takahashi, Emiko; Kakizaki, Hirohiko

    2016-01-01

    Solitary fibrous tumors (SFTs) are benign, spindle-cell tumors of mesenchymal origin that are usually seen in the superior orbital area in adults. We report a rare case of SFT in the lacrimal gland fossa that developed in a young female. A 25-year-old woman had a 6-month history of a progressive painless mass in the left upper eyelid accompanied by proptosis. Computed tomography and magnetic resonance imaging showed an ovoid, demarcated mass with distinct margins in the lacrimal gland region without bone invasion. Excision biopsy with immunohistochemical study, specifically with positive signal transducer and activator of transcription 6, confirmed the diagnosis. PMID:27721790

  16. Unusual Presentation of Hepatocellular Carcinoma into Right iliac fossa: A Rare Entity

    PubMed Central

    Periyasamy, Karthikumaran

    2015-01-01

    Hepatocellular carcinoma (HCC) is the most common primary malignant hepatic tumour. Hepatocellular carcinoma presenting itself or extending into the right iliac fossa (RIF) is a very rare entity. We report on a rare case of hepatocellular carcinoma in a 60-year-old lady, presented with a mobile mass in the lower abdomen without cirrhosis, with normal α-feto protein levels (AFP) or any known risk factors for liver disease. HCC in this case was unusual in its presentation both in the patient as well as a disease. PMID:26672490

  17. ModFossa: A library for modeling ion channels using Python.

    PubMed

    Ferneyhough, Gareth B; Thibealut, Corey M; Dascalu, Sergiu M; Harris, Frederick C

    2016-06-01

    The creation and simulation of ion channel models using continuous-time Markov processes is a powerful and well-used tool in the field of electrophysiology and ion channel research. While several software packages exist for the purpose of ion channel modeling, most are GUI based, and none are available as a Python library. In an attempt to provide an easy-to-use, yet powerful Markov model-based ion channel simulator, we have developed ModFossa, a Python library supporting easy model creation and stimulus definition, complete with a fast numerical solver, and attractive vector graphics plotting.

  18. Geologic Mapping along the Arabia Terra Dichotomy Boundary: Mawrth Vallis and Nili Fossae, Mars

    NASA Technical Reports Server (NTRS)

    Bleamaster, Leslie F., III; Crown, David A.

    2009-01-01

    Geologic mapping studies at the 1:1M-scale are being used to assess geologic materials and processes that shape the highlands along the Arabia Terra dichotomy boundary. In particular, this mapping will evaluate the distribution, stratigraphic position, and lateral continuity of compositionally distinct outcrops in Mawrth Vallis and Nili Fossae as identified by spectral instruments currently in orbit. Placing these landscapes, their material units, structural features, and unique compositional outcrops into spatial and temporal context with the remainder of the Arabia Terra dichotomy boundary may provide constraints on: 1) origin of the dichotomy boundary, 2) paleo-environments and climate conditions, and 3) various fluvial-nival modification processes related to past and present volatile distribution and their putative reservoirs (aquifers, lakes and oceans, surface and ground ice) and the influences of nearby volcanic and tectonic features on hydrologic processes in these regions. The results of this work will include two 1:1M scale geologic maps of twelve MTM quadrangles (Mawrth Vallis - 20022, 20017, 20012, 25022, 25017, and 25012; and Nili Fossae - 20287, 20282, 25287, 25282, 30287, 30282).

  19. Geologic Mapping along the Arabia Terra Dichotomy Boundary: Mawrth Vallis and Nili Fossae, Mars: Introductory Report

    NASA Technical Reports Server (NTRS)

    Bleamaster, Leslie F., III; Crown, David A.

    2008-01-01

    Geologic mapping studies at the 1:1M-scale will be used to characterize geologic processes that have shaped the highlands along the Arabia Terra dichotomy boundary. In particular, this mapping will evaluate the distribution, stratigraphic position, and lateral continuity of compositionally distinct outcrops in Mawrth Vallis and Nili Fossae as identified by spectral instruments currently in orbit. Placing these landscapes, their material units, structural features, and unique compositional outcrops into spatial and temporal context with the remainder of the Arabia Terra dichotomy boundary will provide the ability to: 1) further test original dichotomy formation hypotheses, 2) constrain ancient paleoenvironments and climate conditions, and 3) evaluate various fluvial-nival modification processes related to past and present volatile distribution and their putative reservoirs (aquifers, lakes and oceans, surface and ground ice) and the influences of nearby volcanic and tectonic features on hydrologic processes in these regions. The result will be two 1:1M scale geologic maps of twelve MTM quadrangles (Mawrth Vallis - 20022, 20017, 20012, 25022, 25017, and 25012; and Nili Fossae - 20287, 20282, 25287, 25282, 30287, 30282).

  20. Unusual foramen in the middle cranial fossae of adult black South African skull specimens.

    PubMed

    Mazengenya, Pedzisai; Ekpo, Okobi

    2016-11-11

    Variations of the skull base foramina are quite common and often cause surgical confusion during surgical intervention of the region. The unusual foramen was observed in five (0.98%) adult skulls of black South Africans obtained from the Raymond A Dart collection of human specimens housed in the School of Anatomical Sciences at the University of the Witwatersrand. Three of the five specimens were females while the remaining two were males. In four of the five skulls, the unusual foramen was located anterolateral to the foramen rotundum both on the left and right sides. In the fifth specimen, the foramen was located posterolateral to the foramen rotundum on the left half of the middle cranial fossa. On radiographs, two specimens with unusual foramen on the right showed that the foramen opened into a canal directed inferomedially towards the pterygopalatine fossa. In the remaining three specimens, the canals were blind and shallow. This information is vital during interpretation of CT scans at the base of the skull, as any less well-known foramen may be mistaken for abnormalities leading to surgical complications.

  1. Assessment of Condyle and Glenoid Fossa Morphology Using CBCT in South-East Asians

    PubMed Central

    Al-koshab, May; Nambiar, Phrabhakaran; John, Jacob

    2015-01-01

    Introduction Proper imaging allows practitioners to evaluate an asymptomatic tempormandibular joint (TMJ) for potential degenerative changes prior to surgical and orthodontic treatment. The recently developed cone-beam computed tomography (CBCT) allows measurement of TMJ bony structures with high accuracy. A study was undertaken to determine the morphology, and its variations, of the mandibular condyle and glenoid fossa among Malay and Chinese Malaysians. Methods CBCT was used to assess 200 joints in 100 subjects (mean age, 30.5 years). i-CAT CBCT software and The Mimics 16.0 software were employed to measure the volume, metrical size, position of each condyle sample and the thickness of the roof of the glenoid fossa (RGF). Results No significant gender differences were noted in thickness of the RGF and condylar length; however condylar volume, width, height and the joint spaces were significantly greater among males. With regards to comparison of both TMJs, the means of condylar volume, width and length of the right TMJ were significantly higher, while the means of the left condylar height and thickness of RGF were higher. When comparing the condylar measurements and the thickness of RGF between the two ethnic groups, we found no significant difference for all measurements with exception of condylar height, which is higher among Chinese. Conclusion The similarity in measurements for Malays and Chinese may be due to their common origin. This information can be clinically useful in establishing the diagnostic criteria for condylar volume, metrical size, and position in the Malaysian East Asians population. PMID:25803868

  2. Primary non-Hodgkin's lymphoma of the infratemporal fossa: a rare case report

    PubMed Central

    Thakur, Jagdeep S; Minhas, Ravinder S; Mohindroo, Narinder K; Sharma, Dev R; Mohindroo, Shobha; Thakur, Anamika

    2009-01-01

    Background The head and neck are two of the most common sites of extranodal non-Hodgkin's lymphoma (NHL). However, primary tumors of the infratemporal fossa are infrequent, and NHL in this region is extremely rare. Case presentation We present a case of a 41-year-old female that presented with swelling in the right preauricular region that had persisted for the past two years. The patient was diagnosed as having a small lymphocytic NHL. She initially underwent chemo-radiation but reported relapse. The tumor was excised and again the patient underwent chemotherapy. The patient remained symptomatic and developed a second primary squamous cell carcinoma in the right retromolar trigone. Discussion and conclusion We discussed NHL with an emphasis on extranodal manifestations. Extranodal NHL that is limited to a single site can be managed by surgery and regular follow up. To the best of our knowledge, this is only the second case of primary NHL of the infratemporal fossa to be reported in the literature. PMID:19545392

  3. Endoscopic versus Open Approach to the Infratemporal Fossa: A Cadaver Study

    PubMed Central

    Youssef, Ahmed; Carrau, Ricardo L.; Tantawy, Ahmed; Ibraheim, Ahmed; Solares, Arturo C.; Otto, Bradley A.; Prevedello, Daniel M.; Filho, Leo Ditzel

    2015-01-01

    Introduction Various lateral and anterior approaches to access the infratemporal fossa (ITF) have been described. We provide our observations regarding the endoscopic transpterygoid and preauricular subtemporal approaches, listing their respective advantages and limitations through cadaveric dissection. Methods A cadaver study was performed on five adult specimens. An endoscopic transpterygoid approach to the ITF was completed bilaterally in three specimens, and an open preauricular ITF approach was performed bilaterally in two specimens. Results After completing the cadaveric dissections, we studied differences between the endoscopic transpterygoid approach and open preauricular subtemporal approaches in regard to exposure and ease of dissection of different structures in the ITF. Conclusions In comparison with a lateral approach, the endonasal endoscopic transpterygoid approach provides better visualization and more direct exposure of median structures such as the nasopharynx, eustachian tube, sella, and clivus. We concluded that the endoscopic transpterygoid approach can be utilized to resect benign lesions and some select group of malignancies involving the infratemporal and middle cranial fossae. Open approaches continue to play an important role, especially in the resection of extensive malignant tumors extending to these regions. PMID:26401477

  4. Effects of friction massage of the popliteal fossa on dynamic changes in muscle oxygenation and ankle flexibility

    PubMed Central

    Iwamoto, Koji; Mizukami, Masafumi; Asakawa, Yasutsugu; Yoshio, Masaharu; Ogaki, Ryo; Takemura, Masahiro

    2016-01-01

    [Purpose] This study aimed to examine whether or not friction massage of the popliteal fossa would be effective for achieving dynamic changes in muscle oxygenation and ankle flexibility. [Subjects and Methods] Twelve healthy male university students participated. Before and after friction massage, dynamic changes in muscle oxygenation and ankle flexibility were measured by near-infrared spectroscopy to evaluate its efficacy. [Results] Oxygenated hemoglobin was significantly higher after as compared to before massage. The range of ankle dorsiflexion tended to increase after massage. [Conclusion] These results suggest that friction massage of the popliteal fossa stimulates venous return in the lower leg. PMID:27821920

  5. Posterior commissure of the human larynx revisited.

    PubMed

    Tucker, John A; Tucker, Sean T

    2010-05-01

    The existence of the posterior commissure (PC) of the human larynx has been disputed (Hirano M, Sato K, et al. The posterior glottis. Trans Am Laryngol Assoc. 1986;107:70-75). "The term posterior commissure has no relevance to anatomical structure. The term commissure means a joining together. The bilateral vocal folds never join at their posterior ends. The posterior aspect of the glottis is a wall. The posterior lateral aspect of the posterior glottis is also the lateral wall of the posterior glottis" (Hirano M, Sato K, et al. The posterior glottis. Trans Am Laryngol Assoc. 1986;107:70-75). This study is intended to clarify the development of anatomical and morphological aspects of the PC in conjunction with a clinical classification of the larynx in sagittal view. This study uses human embryo and fetal laryngeal sections from the Carnegie Collection of Human Embryos (the world standard) and whole organ laryngeal sections from the Tucker Laryngeal Fetal Collection. Correlation of histologic and gross anatomical structure is made with the Hirano et al atlas, the Vidić Photographic Atlas of the Human Body, and the O'Rahilly Embryonic Atlas. Embryologic data clearly describe and illustrate the posterior union of the cricoid cartilage with formation of the PC. The anatomical functional aspects of the posterior lateral cricoid lamina as the supporting buttress of the articulating arytenoid cartilages are illustrated.

  6. Isolated posterior cruciate ligament calcification

    PubMed Central

    Koukoulias, Nikolaos E; Papastergiou, Stergios G

    2011-01-01

    The authors present a case of calcified posterior cruciate ligament (PCL). A 61-year-old female presented in our department reporting 12 months history of knee pain that was getting worse during the night. The patient was under medication for epileptic seizure, osteoporosis and hyperthyroidism. X-rays demonstrated calcification of the PCL. CT and MRI excluded any other intra-articular and extra-articular pathology. Arthroscopic debridement of the calcium deposits was performed and the symptoms resolved immediately, while the postoperative x-rays were normal. Histological examination confirmed the calcium nature of the lesion. Two years postoperatively the patient remains asymptomatic. PMID:22669889

  7. Huge interparietal posterior fontanel meningohydroencephalocele

    PubMed Central

    Dos Santos, Manuel Filipe Dias; de Santa Barbara, Rita de Cassia

    2015-01-01

    Congenital encephalocele is a neural tube defect characterized by a sac-like protrusion of the brain, meninges, and other intracranial structures through the skull, which is caused by an embryonic development abnormality. The most common location is at the occipital bone, and its incidence varies according to different world regions. We report a case of an 1-month and 7-day-old male child with a huge interparietal-posterior fontanel meningohydroencephalocele, a rare occurrence. Physical examination and volumetric computed tomography were diagnostic. The encephalocele was surgically resected. Intradural and extradural approaches were performed; the bone defect was not primarily closed. Two days after surgery, the patient developed hydrocephaly requiring ventriculoperitoneal shunting. The surgical treatment of the meningohydroencephalocele of the interparietal-posterior fontanel may be accompanied by technical challenges and followed by complications due to the presence of large blood vessels under the overlying skin. In these cases, huge sacs herniate through large bone defects including meninges, brain, and blood vessels. The latter present communication with the superior sagittal sinus and ventricular system. A favorable surgical outcome generally follows an accurate strategy taking into account individual features of the lesion. PMID:26484324

  8. Longevity of Posterior Composite Restorations

    PubMed Central

    Opdam, N.J.M.; van de Sande, F.H.; Bronkhorst, E.; Cenci, M.S.; Bottenberg, P.; Pallesen, U.; Gaengler, P.; Lindberg, A.; Huysmans, M.C.D.N.J.M.; van Dijken, J.W.

    2014-01-01

    The aim of this meta-analysis, based on individual participant data from several studies, was to investigate the influence of patient-, materials-, and tooth-related variables on the survival of posterior resin composite restorations. Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we conducted a search resulting in 12 longitudinal studies of direct posterior resin composite restorations with at least 5 years’ follow-up. Original datasets were still available, including placement/failure/censoring of restorations, restored surfaces, materials used, reasons for clinical failure, and caries-risk status. A database including all restorations was constructed, and a multivariate Cox regression method was used to analyze variables of interest [patient (age; gender; caries-risk status), jaw (upper; lower), number of restored surfaces, resin composite and adhesive materials, and use of glass-ionomer cement as base/liner (present or absent)]. The hazard ratios with respective 95% confidence intervals were determined, and annual failure rates were calculated for subgroups. Of all restorations, 2,816 (2,585 Class II and 231 Class I) were included in the analysis, of which 569 failed during the observation period. Main reasons for failure were caries and fracture. The regression analyses showed a significantly higher risk of failure for restorations in high-caries-risk individuals and those with a higher number of restored surfaces. PMID:25048250

  9. [Dissecting aneurysm of the posterior inferior cerebellar artery--studied by serial angiography].

    PubMed

    Yamashita, Y; Hayashi, S; Saitho, H; Teramoto, A

    2001-11-01

    We report the case of a 34-year-old male with cerebellar hemorrhagic infarction caused by a dissecting aneurysm of the left posterior inferior cerebellar artery (PICA). The patient suffered from a headache and vomiting for two days and was transferred to our hospital with sudden deterioration of consciousness. On admission, he was semicomatose. A CT scan revealed hemorrhagic infarction in the left cerebellum and upward herniation. The emergency operation for posterior fossa decompression was performed. Postoperatively, his consciousness level improved promptly and he had no neurological deficits except for slight gait disturbance. The first vertebral angiography was performed on Day 27. It showed a sausage-like dissecting aneurysm of the left distal PICA. We planned conservative therapy with careful observation because of there being no indication for an operation. Serial angiography was performed and demonstrated the regression of the dissecting aneurysm on Day 258. Dissecting aneurysms of the distal PICA are rare and their natural history is not well understood. Conservative therapy for vertebrobasilar dissecting aneurysms has often been reported. We suggest that conservative therapy with serial angiography is the treatment of choice especially for ischemic-type dissecting aneurysms. We review 17 cases of dissecting aneurysm of the distal PICA in this study.

  10. Topographic Constraints on the Mode of Formation of an Enigmatic Flow in Cerberus Fossae, Mars

    NASA Astrophysics Data System (ADS)

    Mouginis-Mark, P. J.; Wilson, L.

    2013-12-01

    We use a digital elevation model (DEM), derived from stereo Context Camera (CTX) images referenced to Mars Orbiter Laser Altimeter (MOLA) data, and shadow length measurements made from High Resolution Imaging Science Experiment (HiRISE) images, to investigate the geometry of a young enigmatic flow in S.W. Cerberus Fossae, Mars. The flow originates from an almost circular (1.2 x 1.5 km) pit within a remnant of a yardang at 0o 35'N, 155o 17'E, within the lower unit of the Medusae Fossae Formation. The flow is ~42 km long and 0.5 to 2.0 km wide, and MOLA data indicate that the flow falls ~50 m along its length. The flow has a broad distal fan of material ~8 x 14 km in size that has a platey surface texture. The source area of the flow displays several sets of semi-concentric ridges with different centers of curvature, and the CTX DEM shows this depression is ~20 m deep, implying a volume of ~0.03 km3 for the removed material. Measurements made from the DEM of the height of the bounding walls of several 160 - 200 m wide constrictions, where 'over-spill' from the flow forms a clear disrupted margin to the flow on the adjacent hills, indicate that the flow was never more than ~8 - 10 m thicker than it currently appears. The total surface area of the flow is ~153 km2 and 25 shadow length measurements made from HiRISE images of the flow margins at 16 different places along the flow give a typical thickness of ~4 m. These measurements imply a volume for the flow of ~0.6 km3, which is 20 times larger than the volume of the flow's source area, thereby demonstrating that a significant amount of new material was erupted to form the flow. The available morphologic and topographic data raise the intriguing probability that the flow is most likely not a lava flow, but is instead a mud flow produced by water reaching the surface within the yardang materials and the subsequent mobilization of the unconsolidated material that comprised the yardang. This proposed mud flow origin

  11. Carbon Sequestration on Mars: Constraints from the Nili Fossae Carbonate Plains

    NASA Astrophysics Data System (ADS)

    Edwards, C. S.; Ehlmann, B. L.

    2015-12-01

    Martian carbonates have been observed telescopically, from orbit, in situ and in Martian meteorites; however, a long-postulated geologic reservoir that accounts for proposed thinning of a multi-bar early Mars atmosphere by CO2 sequestration has not yet been identified. One striking aspect of the Martian geologic record is the presence of valley networks and open basin lakes last active around the Noachian/Hesperian boundary, at ca. 3.5 Ga. If surface waters were supported by a thicker atmosphere, hundreds of millibars to bars of CO2 would need to be lost to space during the Hesperian/Amazonian, inconsistent with current atmospheric models. Was this late CO2 sequestered in the Martian crust? We consider the role of diffuse and localized CO2 sequestration and constrain the timing and explore implications for late Noachian atmospheric conditions via examination of the age and composition of the largest contiguous exposure of carbonate-bearing rock on Mars, the Nili Fossae carbonate plains (21.5°N, 78.5°E). Morphological, spectral and thermophysical data sets from the Thermal Emission Spectrometer, Compact Reconnaissance Imaging Spectrometer for Mars, Thermal Emission Imaging System, and High Resolution Imaging Science Experiment are considered in the context of past atmospheric drawdown. We find the olivine-enriched (~20%-25%) basalts of the Nili Fossae plains have been altered, by low-temperature, in-situ carbonation processes, to at most ~20% Fe-Mg carbonate, thus limiting carbon sequestration in the Nili Fossae region to ~0.25-12 mbar of CO2 during the late Noachian/early Hesperian, before or concurrent with valley network formation. While large compared to modern-day CO2 reservoirs, the lack of additional, comparable-sized post-Late Noachian carbonate-bearing deposits on Mars indicates ineffective carbon sequestration in rock units over the past ~3.7 Ga. This implies a thin atmosphere (≲500 mbar) during valley network formation, extensive post

  12. Usefulness of high-resolution 3D multifusion medical imaging for preoperative planning in patients with posterior fossa hemangioblastoma: technical note.

    PubMed

    Yoshino, Masanori; Nakatomi, Hirofumi; Kin, Taichi; Saito, Toki; Shono, Naoyuki; Nomura, Seiji; Nakagawa, Daichi; Takayanagi, Shunsaku; Imai, Hideaki; Oyama, Hiroshi; Saito, Nobuhito

    2016-08-26

    Successful resection of hemangioblastoma depends on preoperative assessment of the precise locations of feeding arteries and draining veins. Simultaneous 3D visualization of feeding arteries, draining veins, and surrounding structures is needed. The present study evaluated the usefulness of high-resolution 3D multifusion medical imaging (hr-3DMMI) for preoperative planning of hemangioblastoma. The hr-3DMMI combined MRI, MR angiography, thin-slice CT, and 3D rotated angiography. Surface rendering was mainly used for the creation of hr-3DMMI using multiple thresholds to create 3D models, and processing took approximately 3-5 hours. This hr-3DMMI technique was used in 5 patients for preoperative planning and the imaging findings were compared with the operative findings. Hr-3DMMI could simulate the whole 3D tumor as a unique sphere and show the precise penetration points of both feeding arteries and draining veins with the same spatial relationships as the original tumor. All feeding arteries and draining veins were found intraoperatively at the same position as estimated preoperatively, and were occluded as planned preoperatively. This hr-3DMMI technique could demonstrate the precise locations of feeding arteries and draining veins preoperatively and estimate the appropriate route for resection of the tumor. Hr-3DMMI is expected to be a very useful support tool for surgery of hemangioblastoma.

  13. Relationships Between the Medusae Fossae Formation (MFF), Fluvial Channels, and the Dichotomy Boundary Southeast of Nicholson Crater, Mars

    NASA Technical Reports Server (NTRS)

    Bradley, B. A.; Sakimoto, S. E. H.

    2001-01-01

    We use Mars Global Surveyor's Mars Orbiter Laser Altimeter (MOLA) and Mars Orbiter Camera (MOC) data to investigate the Medusae Fossae Formation (MFF) and its relationship to fluvial channels southeast of Nicholson Crater. In this area the MFF shows small-scale layering and is draped over Labou Vallis. Additional information is contained in the original extended abstract.

  14. Mapping of Sand Types and Dune Morphologies in the Aeolis Dorsa Region, Western Medusae Fossae Formation, Mars

    NASA Astrophysics Data System (ADS)

    Boyd, A. S.; Burr, D. M.

    2016-06-01

    Preliminary mapping of low- and high-albedo sand deposits in the Aeolis Dorsa region, Medusae Fossae Formation (MFF), suggests sand transport from the north, consistent with sand source(s) in Elysium Mons, the Cerberus plains, or the MFF itself.

  15. Imaging of the Posterior Skull Base.

    PubMed

    Job, Joici; Branstetter, Barton F

    2017-01-01

    The posterior skull base can be involved by a variety of pathologic processes. They can be broadly classified as: traumatic, neoplastic, vascular, and inflammatory. Pathology in the posterior skull base usually involves the lower cranial nerves, either as a source of pathology or a secondary source of symptoms. This review will categorize pathology arising in the posterior skull base and describe how it affects the skull base itself and surrounding structures.

  16. Posterior ankle impingement in the dancer.

    PubMed

    Moser, Brad R

    2011-01-01

    Dancers spend a lot of time in the relevé position in demi-pointe and en pointe in their training and their careers. Pain from both osseous and soft tissue causes may start to occur in the posterior aspect of their ankle. This article reviews the potential causes of posterior ankle impingement in dancers. It will discuss the clinical evaluation of a dancer and the appropriate workup and radiographic studies needed to further evaluate a dancer with suspected posterior ankle impingement.

  17. Geologic Mapping Applications Using THEMIS Data for the Medusae Fossae Formation, Mars

    NASA Technical Reports Server (NTRS)

    Zimbelman, J. R.; Bender, K. C.; Harris, J. C.

    2003-01-01

    The Medusae Fossae Formation (MFF) is a regionally extensive deposit located along the equator of Mars between roughly 130 and 240 E longitude, the origin of which has stimulated a host of published hypotheses. A volcanic or aeolian origin appear most consistent with Viking and MGS data, but other hypotheses remain viable and new data, as from the Mars Odyssey spacecraft, is likely to stimulate additional hypotheses of origin. NASA is supporting geologic mapping of portions of the MFF deposits, but it is now quite clear that this on-going mapping will need considerable revision as data from the Thermal Emission Imaging System (THEMIS) on Mars Odyssey become available. The daytime IR THEMIS images hold particularly strong potential for providing a new base on which geologic mapping can be carried out, as illustrated by the examples discussed.

  18. Cholecystokinin-Assisted Hydrodissection of the Gallbladder Fossa during FDG PET/CT-guided Liver Ablation

    SciTech Connect

    Tewari, Sanjit O.; Petre, Elena N.; Osborne, Joseph; Sofocleous, Constantinos T.

    2013-12-15

    A 68-year-old female with colorectal cancer developed a metachronous isolated fluorodeoxyglucose-avid (FDG-avid) segment 5/6 gallbladder fossa hepatic lesion and was referred for percutaneous ablation. Pre-procedure computed tomography (CT) images demonstrated a distended gallbladder abutting the segment 5/6 hepatic metastasis. In order to perform ablation with clear margins and avoid direct puncture and aspiration of the gallbladder, cholecystokinin was administered intravenously to stimulate gallbladder contraction before hydrodissection. Subsequently, the lesion was ablated successfully with sufficient margins, of greater than 1.0 cm, using microwave with ultrasound and FDG PET/CT guidance. The patient tolerated the procedure very well and was discharged home the next day.

  19. Cine-magnetic resonance imaging evaluation of communication between middle cranial fossa arachnoid cysts and cisterns.

    PubMed

    Eguchi, T; Taoka, T; Nikaido, Y; Shiomi, K; Fujimoto, T; Otsuka, H; Takeuchi, H

    1996-06-01

    Cine-magnetic resonance (MR) imaging examinations were performed in 10 patients with middle cranial fossa arachnoid cysts to evaluate communication between the cysts and the normal cerebrospinal fluid (CSF) space. Eight of 10 patients were evaluated by time of flight cine-MR imaging, and two by phase contrast cine-MR imaging. Two patients underwent membranectomy of the cysts, and were evaluated both pre- and postoperatively. Computed tomography cisternography was used to confirm communication between the cysts and the surrounding cisterns. Pulsatile fluid motion within the cysts was present in all patients. However, marked fluid motion and jet flow between the cysts and the surrounding cisterns were only observed in communicating cysts. In the two patients who underwent membranectomy, postoperative examination found greater fluid motion and jet flow not previously present. Cine-MR imaging demonstration of marked pulsatile fluid motion accompanied by jet flow suggests that a cyst communicates with the normal CSF space.

  20. Posterior repair and sexual function

    PubMed Central

    Komesu, Yuko M.; Rogers, Rebecca G.; Kammerer-Doak, Dorothy N.; Barber, Matthew D.; Olsen, Ambre L.

    2011-01-01

    OBJECTIVE The purpose of this study was to determine the effect of posterior repair (PR) on sexual function in patients who have undergone incontinence and/or pelvic reconstructive surgery. STUDY DESIGN A cohort study of women who underwent incontinence and/or prolapse surgery was performed. Participants completed the pelvic organ prolapse urinary incontinence sexual questionnaire (PISQ) before and after the operation. PISQ scores were compared between women who underwent PR and women who did not. RESULTS Of 73 study participants, 30 women underwent PR; 43 women did not (no PR). Although there was no difference in dyspareunia between groups pre-op, dyspareunia prevalence post-op was significantly lower in the no PR group. Preoperative PISQ scores were similar between groups. After the operation, both groups significantly improved their PISQ scores, without a difference between groups. CONCLUSION Although the incidence of dyspareunia differed between PR and no PR groups, overall improvement in sexual function was reflected in improved total PISQ scores that occurred irrespective of PR performance. PMID:17618777

  1. Sinuous Ridges as Tools to Investigate Post-Flow Modification in the Aeolis-Zephyria Plana, Western Medusae Fossae Formation, Mars

    NASA Astrophysics Data System (ADS)

    Lefort, A.; Burr, D. M.; Beyer, R. A.; Howard, A. D.

    2012-03-01

    The longitudinal profiles of inverted fluvial features located in the Medusa Fossae Formation exhibit undulations that we interpret as evidence of post-fluvial deformation of the region. We propose and evaluate possible deformation processes.

  2. Recurrent posterior shoulder instability. Diagnosis and treatment.

    PubMed

    Pollock, R G; Bigliani, L U

    1993-06-01

    Recurrent posterior glenohumeral instability is regarded as a difficult problem to diagnose and treat. A careful history and physical examination are the most helpful tools in making this diagnosis. A positive posterior stress test, demonstrable posterior subluxation, and a sulcus sign are frequently present on examination. Special roentgenographic studies, such as the computerized arthrotomography (arthro-CT) scan, may be used in cases in which plain roentgenographs suggest bony glenoid abnormalities. When conservative therapy fails, there is no consensus on the operative treatment. Procedures that address the soft tissues, such as capsulorrhaphy and posterior labral repair, as well as those that alter the bony geometry of the joint, such as posterior bone blocks and glenoid or humeral osteotomies, have been described. Capsular laxity is the most common pathologic finding in the authors' experience, and they favor the use of a posterior-inferior capsular shift procedure to correct this problem. Augmentation of the repair with a posterior bone block is reserved for unusual cases, such as when glenoid hypoplasia is present or in certain revision situations.

  3. Posterior labral injury in contact athletes.

    PubMed

    Mair, S D; Zarzour, R H; Speer, K P

    1998-01-01

    Nine athletes (seven football offensive linemen, one defensive lineman, and one lacrosse player) were found at arthroscopy to have posterior labral detachment from the glenoid. In our series, this lesion is specific to contact athletes who engage their opponents with arms in front of the body. All patients had pain with bench pressing and while participating in their sport, diminishing their ability to play effectively. Conservative measures were ineffective in relieving their symptoms. Examination under anesthesia revealed symmetric glenohumeral translation bilaterally, without evidence of posterior instability. Treatment consisted of glenoid rim abradement and posterior labral repair with a bioabsorbable tack. All patients returned to complete at least one full season of contact sports and weightlifting without pain (minimum follow-up, > or = 2 years). Although many injuries leading to subluxation of the glenohumeral joint occur when an unanticipated force is applied, contact athletes ready their shoulder muscles in anticipation of impact with opponents. This leads to a compressive force at the glenohumeral joint. We hypothesize that, in combination with a posteriorly directed force at impact, the resultant vector is a shearing force to the posterior labrum and articular surface. Repeated exposure leads to posterior labral detachment without capsular injury. Posterior labral reattachment provides consistently good results, allowing the athlete to return to competition.

  4. Signs of potential renewal of eruptive activity at La Fossa (Vulcano, Aeolian Islands)

    NASA Astrophysics Data System (ADS)

    Montalto, A.

    1996-04-01

    Since the end of the last magmatic eruption (1890), activity of La Fossa (southern Tyrrhenian Sea, Italy) has consisted of fumarolic emissions of fluctuating intensity. Fluids are discharged principally at two fumarolic fields located in the northern rim of the active crater and at the beach sited at its northern foot. Increased thermal, seismic and geochemical activity has been recorded since 1978, when an earthquake of M=5.5 occurred in the region. This paper combines available geophysical and geochemical information in order to develop a tentative interpretation of two episodes of apparent unrest which occurred in 1985 and 1987 1988, enhancing the risk of renewal of the eruptive activity. The 1985 unrest consisted essentially of a sharp build up of the internal pressure in the shallow hydrothermal system, which was induced by the injection of hot gases of magmatic origin. The crater fumaroles displayed significant increases in CO2 and other acid species, but their outlet temperature did not change. Conversely, the 1987 1988 episode was characterized by appreciable modifications at the crater fumaroles, with only secondary effects at the fumarole system of the beach. The sliding of part of the eastern flank of the La Fossa cone into the sea occurred on 20 April 1988, when the region was affected by crustal dilatation producing a seismic sequence of relatively high intensity. Both episodes of unrest were accompanied by increases of local microseismic activity, which affected the nothern sector of the island in 1985, and the southern one in 1988. Finally, a phase of appreciable areal contraction was detected in 1990, probably due to the effect of the cooling and crystallization of magma at relatively shallow depths, accompanying the increased thermal activity at the crater fumaroles. Regional tectonic stress seems to play an important role in the transition of the volcanic system from a phase of relative stability to a phase of apparent unrest, inducing the heating

  5. Peripheral primitive neuroectodermal tumour - a rare cause of a popliteal fossa mass: A case report and review of the literature.

    PubMed

    Davis, Colin M; Choong, Andrew Mtl; Sharp, David; Taheri, Touraj; Senewiratne, Shireen; Hinckley, Vedella

    2014-01-01

    A literature review of peripheral primitive neuroectodermal tumours, illustrated with an index case report describing an 80-year-old woman who presented with a mass in the left popliteal fossa, is reported. An excision biopsy was performed, revealing a possible peripheral primitive neuroectodermal tumour as the primary pathology. Normally confined to the chest wall and axial soft tissues of children and young adults, reports of this tumour existing in other areas and in the elderly population are scarce.

  6. Johann Christian Rosenmüller (1771-1820): A Historical Perspective on the Man behind the Fossa

    PubMed Central

    Amene, Chiazo; Cosetti, Maura; Ambekar, Sudheer; Guthikonda, Bharat; Nanda, Anil

    2013-01-01

    Introduction The fossa of Rosenmüller, also known as the lateral pharyngeal recess, is a well-established site of origin of nasopharyngeal carcinoma. It is located in the lateral pharyngeal wall behind the cartilaginous portion of the Eustachian tube, the torus tubarius, and is named after Johann Christian Rosenmüller (JCR). Objective We present a history on the life and extensive works of Johann Christian Rosenmüller, a German physician and anatomist. Results Johann Christian Rosenmüller was a dedicated anatomist. In addition to identifying the fossa of Rosenmüller, his influence extends to various other anatomic subjects, including the Rosenmüller gland, the palpebral portion of the lacrimal gland, and the organ of Rosenmüller (i.e., the caudal remnant of the mesonephric duct). He was also an avid speleologist, studying the composition of caves and their life forms. For his contributions to this field, he had a cave in Germany and an extinct species named after him—Rosenmüllerhöhle and Ursus spelaeus Rosenmüller, respectively. Conclusion The fossa of Rosenmüller plays an important role in the growth and surgical treatment of nasopharyngeal carcinoma. We present a brief glimpse into the life of Johann Christian Rosenmüller, for whom it was named. PMID:24436911

  7. Functional Outcomes of the Retromaxillary-Infratemporal Fossa Dissection for Advanced Head and Neck/Skull Base Lesions

    PubMed Central

    Shibuya, Terry Y.; Doerr, Timothy D.; Mathog, Robert H.; Burgio, Don L.; Meleca, Robert J.; Yoo, George H.; Guthikonda, Murali

    2000-01-01

    The retromaxillary-infratemporal fossa (RM-ITF) dissection, using a preauricular incision, was initially popularized for the treatment of temporomandibular joint disorders, facial fractures, and orbital tumors. This approach has been expanded for the treatment of advanced head and neck and skull base tumors extending into the infratemporal fossa. We studied prospectively eight consecutive patients requiring a RM-ITF dissection. Pre- and postoperative functional outcomes measured were mastication, speech, swallowing, cranial nerve function, pain, and cosmesis. A significant reduction in pain was noted postoperatively in all patients studied. Limited changes were identified in mastication, speech, swallowing, vision, hearing, or cosmesis postoperatively. The RM-ITF dissection should be considered when resecting advanced head and neck/skull base lesions that extend into this region. We have found minimal morbidity associated with this dissection. This procedure may have a useful place in palliation of patients with incurable pain caused by tumor invasion into the infratemporal fossa. ImagesFigure 2Figure 3Figure 4 PMID:17171134

  8. Outcomes of urethral calculi patients in an endemic region and an undiagnosed primary fossa navicularis calculus.

    PubMed

    Verit, Ayhan; Savas, Murat; Ciftci, Halil; Unal, Dogan; Yeni, Ercan; Kaya, Mete

    2006-02-01

    Urethral calculus is a rare form of urolithiasis with an incidence lower than 0.3%. We determined the outcomes of 15 patients with urethral stone, of which 8 were pediatric, including an undiagnosed primary fossa navicularis calculus. Fifteen consecutive male patients, of whom eight were children, with urethral calculi were assessed between 2000 and 2005 with a mean of 19 months' follow-up. All stones were fusiform in shape and solitary. Acute urinary retention, interrupted or weak stream, pain (penile, urethral, perineal) and gross hematuria were the main presenting symptoms in 7 (46.7%), 4 (26.7%), 3 (20%) and 1 (6.6%) patient, respectively. Six of them had accompanying urethral pathologies such as stenosis (primary or with hypospadias) and diverticulum. Two patients were associated with upper urinary tract calculi but none of them secondary to bladder calculi. A 50-year-old patient with a primary urethral stone disease had urethral meatal stenosis accompanied by lifelong lower urinary tract symptoms. Unlike the past reports, urethral stones secondary to bladder calculi were decreasing, especially in the pediatric population. However, the pediatric patients in their first decade are still under risk secondary to the upper urinary tract calculi or the primary ones.

  9. Can serum interleukin-6 levels predict the outcome of patients with right iliac fossa pain?

    PubMed Central

    Goodwin, A. T.; Swift, R. I.; Bartlett, M. J.; Fernando, B. S.; Chadwick, S. J.

    1997-01-01

    In patients with right iliac fossa (RIF) pain it can be difficult to distinguish between appendicitis and nonspecific abdominal pain (NSAP). In this study we sought to determine whether serum interleukin-6 (IL-6) levels, an early marker of acute inflammation, taken at the time of admission could predict the outcome of patients admitted with RIF pain. Data were collected in a prospective manner on 53 consecutive patients (23 male, 30 female), mean age 22.1 years (range 10-79 years). Nineteen (36%) patients underwent surgery, of whom 16 had appendicitis (histologically proven). The mean (SEM) IL-6 levels (pg/ml) in patients undergoing operation vs those receiving non-operative management were 270.8 (106.3) vs 265.0 (80.4) (P = NS). The mean white blood cell (WBC) counts (x10(9)/l) in these patients were 14.28 (0.81) vs 9.66 (0.67), respectively (P = 0.0002). When patients with a confirmed diagnosis of appendicitis were compared with patients with a diagnosis of NSAP, the IL-6 levels were 149.4 (69.1) vs 363.6 (113.2), respectively (P = NS). In the same groups of patients, the WBC counts were 14.21 (0.81) vs 9.51 (0.68) (P = 0.004). We conclude that IL-6 levels taken at the time of admission are not useful in predicting the outcome of RIF pain. PMID:9135242

  10. Can serum interleukin-6 levels predict the outcome of patients with right iliac fossa pain?

    PubMed

    Goodwin, A T; Swift, R I; Bartlett, M J; Fernando, B S; Chadwick, S J

    1997-03-01

    In patients with right iliac fossa (RIF) pain it can be difficult to distinguish between appendicitis and nonspecific abdominal pain (NSAP). In this study we sought to determine whether serum interleukin-6 (IL-6) levels, an early marker of acute inflammation, taken at the time of admission could predict the outcome of patients admitted with RIF pain. Data were collected in a prospective manner on 53 consecutive patients (23 male, 30 female), mean age 22.1 years (range 10-79 years). Nineteen (36%) patients underwent surgery, of whom 16 had appendicitis (histologically proven). The mean (SEM) IL-6 levels (pg/ml) in patients undergoing operation vs those receiving non-operative management were 270.8 (106.3) vs 265.0 (80.4) (P = NS). The mean white blood cell (WBC) counts (x10(9)/l) in these patients were 14.28 (0.81) vs 9.66 (0.67), respectively (P = 0.0002). When patients with a confirmed diagnosis of appendicitis were compared with patients with a diagnosis of NSAP, the IL-6 levels were 149.4 (69.1) vs 363.6 (113.2), respectively (P = NS). In the same groups of patients, the WBC counts were 14.21 (0.81) vs 9.51 (0.68) (P = 0.004). We conclude that IL-6 levels taken at the time of admission are not useful in predicting the outcome of RIF pain.

  11. Radar sounding of the Medusae Fossae Formation Mars: equatorial ice or dry, low-density deposits?

    PubMed

    Watters, Thomas R; Campbell, Bruce; Carter, Lynn; Leuschen, Carl J; Plaut, Jeffrey J; Picardi, Giovanni; Orosei, Roberto; Safaeinili, Ali; Clifford, Stephen M; Farrell, William M; Ivanov, Anton B; Phillips, Roger J; Stofan, Ellen R

    2007-11-16

    The equatorial Medusae Fossae Formation (MFF) is enigmatic and perhaps among the youngest geologic deposits on Mars. They are thought to be composed of volcanic ash, eolian sediments, or an ice-rich material analogous to polar layered deposits. The Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) instrument aboard the Mars Express Spacecraft has detected nadir echoes offset in time-delay from the surface return in orbits over MFF material. These echoes are interpreted to be from the subsurface interface between the MFF material and the underlying terrain. The delay time between the MFF surface and subsurface echoes is consistent with massive deposits emplaced on generally planar lowlands materials with a real dielectric constant of approximately 2.9 +/- 0.4. The real dielectric constant and the estimated dielectric losses are consistent with a substantial component of water ice. However, an anomalously low-density, ice-poor material cannot be ruled out. If ice-rich, the MFF must have a higher percentage of dust and sand than polar layered deposits. The volume of water in an ice-rich MFF deposit would be comparable to that of the south polar layered deposits.

  12. Origin of the Medusae Fossae Formation, Mars: Insights from a synoptic approach

    NASA Astrophysics Data System (ADS)

    Mandt, Kathleen E.; de Silva, Shanaka L.; Zimbelman, James R.; Crown, David A.

    2008-12-01

    The geologic origin of the Medusae Fossae Formation (MFF) has remained a mystery despite three decades of research. To better constrain its formation, an in-depth analysis of observations made in the literature was combined with a new survey of over 700 Mars Orbiter Camera narrow-angle images of the MFF to identify morphologic characteristics and material properties that define this formation as a whole. While previous work has identified clear agreement on some characteristics, our analysis identifies yardangs, collapse features, and layering as pervasive features of the MFF. Whereas collapse features and layering may implicate several different physical and chemical processes, yardangs provide vital information on material properties that inform about mechanical properties of the MFF lithology. Aspect ratios of megayardangs range from 3:1 to 50:1, and slope analyses reveal heights of up to 200 m with cliffs that are almost vertical. Other yardangs show lower aspect ratios and topographic profiles. These characteristics coupled to the presence of serrated margins, suggest that MFF lithology must be of weakly to heavily indurated material that lends itself to jointing. The characteristics and properties of the MFF are inconsistent with those of terrestrial pyroclastic fall deposits or loess, but are in common with large terrestrial ignimbrites, a hypothesis that explains all key observations with a single mechanism. Yardang fields developed in regionally extensive ignimbrite sheets in the central Andes display morphologic characteristics that correlate with degree of induration of the host lithology and suggest an origin by pyroclastic flow for the MFF.

  13. Medial Cranial Fossa Meningioma Diagnosed as Mixed Anxiety Disorder with Dissociative Symptoms and Vertigo

    PubMed Central

    Ceylan, Emin Mehmet; Evrensel, Alper

    2016-01-01

    Meningiomas are mostly benign tumors of the meninges that may stay clinically silent or present first with psychiatric symptoms only. We present a case of medial cranial fossa meningioma that was first diagnosed as mixed anxiety disorder with dissociative symptoms and vertigo. In light of the intact neurological and vestibular system examination, our patient's vertigo and depersonalization were firstly addressed as psychosomatic symptoms of the psychiatric syndrome. Despite decreased anxiety and improved mood, dissociative symptoms and vertigo were resistant to treatment which prompted further research yielding a left hemisphere localized meningioma. Resection of meningioma resulted in full remission of the patient proving it to be responsible for the etiology of the psychiatric syndrome and vertigo. We suggest that brain imaging should be performed for patients with late-onset (>50 years) psychiatric symptoms and those with treatment resistance. It is important to keep in mind always that medically unexplained symptoms may become explicable with detailed assessment and regular follow-up of the patient. PMID:27651969

  14. Geology of Hebrus Valles and Hephaestus Fossae, Mars: evidence for basement control of fluvial patterns

    SciTech Connect

    Christiansen, E.H.

    1985-01-01

    Hebrus Valles (HV) and Hephaestus Fossae (HF) are valley systems located SW of Elysium Mons in the low northern plains of Mars. HV share many of their characteristics with other martian outflow channels--widely interpreted as having formed by catastrophic flooding. The NW-trending HV system is 250 km long and begins in an elongate depression. Individual channels are less than 1 km wide; a braided reach is about 10 km wide. Streamlined islands are abundant in the middle reach. HV terminate as a series of narrow distributaries. No sedimentary deposits are obviously related to the development of the channel. HV cut across a broad expanse of older plains dotted by irregular mesas and smaller knobs. HF are a connected series of linear valley segments which branch and cross downslope but have high junction angles. Locally, the channel pattern is polygonal. HF are parallel to HV but are considerably deeper and longer (600 km). HF also originate in a depression, but to the NW they terminate near the gradational boundary between the knobby plains and polygonally fractured terrain of Utopia Planitia. The valley pattern has led some to suggest that HF are tectonic features. It is suggested that like HV, HF are also of fluvial origin. Downcutting to, or subsurface flow at this pre-existing surface red to a channel pattern that was strongly controlled by the polygonal troughs buried beneath the younger knobby plains materials.

  15. Assessment of Consistency Between the Arm-Fossa Test and Gillet Test: A Pilot Study

    PubMed Central

    Cooperstein, Robert; Blum, Charles; Cooperstein, Elaine C.

    2015-01-01

    Objective The purpose of this pilot study was to test methods needed to conduct a study with adequate power to investigate consistency between the arm-fossa test (AFT) and the Gillet test. Methods A convenience sample of chiropractic college students enrolled in a weekend Sacro-Occipital Technique seminar participated. Each was tested with AFT and sacroiliac orthopedic tests, including the Gillet test. Statistical testing included calculation of κ for consistency of the AFT and Gillet test and their diagnostic efficiency. Results This study recruited 14 participants. Important issues arose in gathering and recording data, the standardization of examiner methods, and the flow of participants to examination stations. κ for AFT and Gillet test consistency = 0.55, corresponding to “moderate.” Conclusion This pilot suggests that the future study should include a mix of symptomatic and asymptomatic participants; record trichotomous data, where appropriate; use washout periods between diagnostic tests; and refine the selection of orthopedic tests deployed besides the AFT. The preliminary data are consistent with but do not establish due to the very small sample size and experimental design issues, that a positive AFT may be consistent with a negative Gillet test. PMID:26693214

  16. Cerberus Fossae and Elysium Planitia Lavas, Mars: Source Vents, Flow Rates, Edifice Styles and Water Interactions

    NASA Technical Reports Server (NTRS)

    Sakimoto, S. E. H.; Gregg, T. K. P.

    2004-01-01

    The Cerberus Fossae and Elysium Planitia regions have been suggested as some of the youngest martian surfaces since the Viking mission, although there was doubt whether the origins were predominantly volcanic or fluvial. The Mars Global Surveyor and Mars Odyssey Missions have shown that the region is certainly young in terms of the topographic preservation and the youthful crater counts (e.g. in the tens to a few hundred million yrs.). Numerous authors have shown that fluvial and volcanic features share common flow paths and vent systems, and that there is evidence for some interaction between the lava flows and underlying volatiles as well as the use by lavas and water of the same vent system. Given the youthful age and possible water-volcanism interaction environment, we'd like constraints on water and volcanic flux rates and interactions. Here, we model ranges of volcanic flow rates where we can well-constrain them, and consider the modest flow rate results results in context with local eruption styles, and track vent locations, edifice volumes, and flow sources and data.

  17. Subtemporal-anterior transtentoral approach to middle cranial fossa microsurgical anatomy.

    PubMed

    Xu, Zhiming; Wang, Weimin; Zhang, Jingjing; Liu, Wei; Feng, Yugong; Li, Gang

    2014-11-01

    This study aimed to describe the topography of inferior and external dura mater of the middle cranial fossa through subtemporal-anterior transpetrosal approach and discuss the feasibility of improving the approach. Eight formalin-fixed adult cadaveric heads were studied, with the bones milled away in the lateral triangle region of the petrous bone, Kawase rhombus region, and inner triangle region of the petrous apex. The distances between the targets in these regions, as well as the angles after the dissection of zygomatic arch, were measured, and then the exposed petroclival and retrochiasmatic areas were observed under the microscope. There were significant variations in the distances between targets in the 3 milled regions among the specimens. After the dissection of zygomatic arch, the surgical view got an average increase of 12 degrees. The subtemporal anterior transpetrosal approach, as an improved subtemporal approach, can expose the lesions optimally, causing no injury to the hearing and reducing injuries to temporal lobe. On the other hand, the lateral bone of the petrous parts of the temporal bone is removed so as to improve the view to the retrochiasmatic area and expand the operative field.

  18. Management of CSF leakage after microsurgery for vestibular schwannoma via the middle cranial fossa approach.

    PubMed

    Scheich, Matthias; Ginzkey, Christian; Ehrmann-Müller, Desiree; Shehata-Dieler, Wafaa; Hagen, Rudolf

    2016-10-01

    Microsurgery is one of the primary current standard options for the treatment of vestibular schwannoma (VS). Especially the middle cranial fossa (MCF) approach is a safe and efficacious technique for the preservation of hearing and facial nerve function in small VS. Postoperative complications are rare, although a leakage of cerebrospinal fluid (CSF) is common. The aim of this study was to analyze postoperative CSF leaks and to describe strategies for postoperative treatment. Between October 2005 and May 2012, 148 patients suffering from VS and selected for microsurgery via the MCF approach were treated in our department. Postoperative CSF leakage occurred in 19 patients. We found a leakage via the Eustachian tube into the nasopharynx in 18 patients and one case of incisional leakage. In 13 cases leaking stopped within 5 days by conservative management including bed rest and intravenous (i.v) antibiotics. Five patients needed lumbar drainage (LD) and only two patients had to undergo revision surgery to seal and pack the mastoid. Analyzed risk factors were age, gender, tumor size and pneumatization of the mastoid. Only the latter showed a significant influence on CSF leakage. We could demonstrate that a stepwise strategy is needed for successful treatment of CSF leaks.

  19. Volcanic emissions from soils at the base of La Fossa volcano, Vulcano island, Italy

    NASA Astrophysics Data System (ADS)

    Obenholzner, J. H.; Parks, J. L.

    2006-12-01

    A top-sealed plastic tube with a diameter of ca. 15 cm had been buried vertically at the base of La Fossa volcano, Volcano island, Italy, next to the front of the obsidian flow. The tube had been filled with quartz wool to condense vapors emanating from the soil. At ca. 75 cm below the surface the sample had been exposed to vapors from Sept. 2005 to April 2006. The leached sample had not been in touch with the ground. Another glass wool cushion (ca. 3 cm thick) had been underneath to minimize capillary effects. Leaching of the quartz wool and ICP-MS analysis documented positive values for: Mg, Al, Si, P, K, Ca, Cr, Mn, Ni, Cu, Zn, Cd, Sn, Pb. Leaching with nitric acid documented also V and Fe. Acid leaching produced higher values for all elements, except K and Sn, than leaching with deionized water. Negative values had been obtained for As, Se, Mo. Influence from soil breathing can be excluded as the active fumaroles contain As and Se. This experiment documents for the first time an unknown element transport by vapors/gases through a volcanic edifice interacting with hydrothermal and magmatic gases. It remains unknown if elements detected are entering the atmosphere or are getting adsorbed onto the volcanic ash soil particles derived from reworked surge beds. This question is very important as soils might be an unknown filter medium to filter volcanically polluted air in case of major volcanic crises. Data can be obtained from the authors.

  20. Posterior Hip Pain in an Athletic Population

    PubMed Central

    Frank, Rachel M.; Slabaugh, Mark A.; Grumet, Robert C.; Virkus, Walter W.; Bush-Joseph, Charles A.; Nho, Shane J.

    2010-01-01

    Context: Posterior hip pain is a relatively uncommon but increasingly recognized complaint in the orthopaedic community. Patient complaints and presentations are often vague or nonspecific, making diagnosis and subsequent treatment decisions difficult. The purposes of this article are to review the anatomy and pathophysiology related to posterior hip pain in the athletic patient population. Evidence Acquisition: Data were collected through a thorough review of the literature via a MEDLINE search of all relevant articles between 1980 and 2010. Results: Many patients who complain of posterior hip pain actually have pain referred from another part of the body—notably, the lumbar spine or sacroiliac joint. Treatment options for posterior hip pain are typically nonoperative; however, surgery is warranted in some cases. Conclusions: Recent advancements in the understanding of hip anatomy, pathophysiology, and treatment options have enabled physicians to better diagnosis athletic hip injuries and select patients for appropriate treatment. PMID:23015944

  1. Posterior cruciate ligament (PCL) injury - aftercare

    MedlinePlus

    Adib F, Curtis C, Bienkowski P Micheli LJ. Posterior cruciate ligament sprain. In: Frontera WR, Silver JK, Rizzo TD Jr, eds. Essentials of Physical Medicine and Rehabilitation: Musculoskeletal Disorders, ...

  2. Gibbs Sampling for Marginal Posterior Expectations

    DTIC Science & Technology

    1991-11-19

    Achcar and Smith (1989) shows that performance of the Laplace method is often very sensitive to parametrization. Morris (1988) offers expansions based on...Berkeley Symp. 1, 453-468. Lindley, D.V. (1980). "Approximate Bayesian Methods" in Bayesian Statistics, J.M. Bernardo, M.H. DeGroot , D.V. Lindley...A.F.M. Smith, University Press, Valencia, Spain. Morris , C. "Approximating Posterior Distributions and Posterior Moments" In: Bayesian Statistics 3, J.M

  3. [Posterior cortical atrophy (Benson-syndrome)].

    PubMed

    Rózsa, Anikó; Szilvássy, Ildikó; Kovács, Krisztina; Boór, Krisztina; Gács, Gyula

    2010-01-30

    We present the characteristics of posterior cortical atrophy--a very rare cortical dementia--in a 69 year old woman's case. Our patient's symptoms began with a visual problem which was initially explained by ophthalmological disorder. After neurological exam visual agnosia was diagnosed apart from other cognitive disorder (alexia without agraphia, acalculia, prosopagnosia, constructional disorder, clock-time recognition disorder, dressing apraxia, visuospatial disorientation). The brain MRI showed bilateral asymmetric parieto-occipital atrophy which is characteristic of posterior cortical atrophy.

  4. Posterior Wnts Have Distinct Roles in Specification and Patterning of the Planarian Posterior Region.

    PubMed

    Sureda-Gómez, Miquel; Pascual-Carreras, Eudald; Adell, Teresa

    2015-11-05

    The wnt signaling pathway is an intercellular communication mechanism essential in cell-fate specification, tissue patterning and regional-identity specification. A βcatenin-dependent signal specifies the AP (Anteroposterior) axis of planarians, both during regeneration of new tissues and during normal homeostasis. Accordingly, four wnts (posterior wnts) are expressed in a nested manner in central and posterior regions of planarians. We have analyzed the specific role of each posterior wnt and the possible cooperation between them in specifying and patterning planarian central and posterior regions. We show that each posterior wnt exerts a distinct role during re-specification and maintenance of the central and posterior planarian regions, and that the integration of the different wnt signals (βcatenin dependent and independent) underlies the patterning of the AP axis from the central region to the tip of the tail. Based on these findings and data from the literature, we propose a model for patterning the planarian AP axis.

  5. Vertigo due to posterior circulation stroke.

    PubMed

    Kim, Ji Soo; Lee, Hyung

    2013-07-01

    Stroke in the distribution of the posterior circulation may present as acute onset spontaneous vertigo and imbalance. Although vertigo due to posterior circulation stroke is usually associated with other neurologic symptoms or signs, small infarcts in the cerebellum or brainstem can present with vertigo without other localizing symptoms. Approximately 17% of patients with isolated posterior inferior cerebellar artery territory infarction presented with isolated vertigo, nystagmus, and postural unsteadiness. A head impulse test can differentiate acute isolated vertigo associated with cerebellar stroke from more benign disorders involving the inner ear. Sometimes acute isolated audiovestibular loss can be the initial symptom of impending posterior circulation ischemic stroke (particularly within the territory of the anterior inferior cerebellar artery). In this case, evaluation of isolated audiovestibular loss may prevent the progression of acute vertigo and hearing loss into more widespread areas of infarction in the posterior circulation. In this article, the clinical syndromes and signs of acute vestibular syndrome due to posterior circulation stroke involving the brainstem and cerebellum are summarized.

  6. Posterior urethral polyp with type I posterior urethral valves: a rare association in a neonate.

    PubMed

    Kesan, Krushnakumar V; Gupta, Rahul Kumar; Kothari, Paras; Gupta, Abhaya; Mudkhedkar, Kedar; Kamble, Ravikiran; Dikshit, K Vishesh

    2014-06-01

    Urethral polyp is a rare cause of bladder outlet obstruction, voiding dysfunction, and hematuria in the pediatric age group. Urethral polyps are rarely associated with other congenital urinary tract anomalies. In this study, we report a case of solitary posterior urethral polyp with type I posterior urethral valve in a 7-day-old neonate presented with urinary retention and deranged renal function. The polyp was diagnosed on cystoscopy. Transurethral resection of the polyp with posterior urethral valve fulguration was performed. Pathologic assessment revealed a fibroepithelial lesion, which was consistent with congenital posterior urethral polyp.

  7. Geological Structure of the Itoigawa - Shizuoka Tectonic Line, Northern Fossa Magna, Central Japan

    NASA Astrophysics Data System (ADS)

    Kim, H.; Iwasaki, T.

    2009-12-01

    Geological structure of two different natures is recognized in the Northern Fossa Magna (NFM). NFM is situated near the zone where the central Japan Island bent geographically and a graben zone formed between the North Alps and the Kanto highland. NFM is characterized by thick Neogene deposits and with active tilting of the crustal blocks and active folding bloc. At the present the sedimentary basin is the Saigawa hill due to the active faulting and folding in the Fossa Magna. Active fault system of Itoigawa-Shizuoka Tectonic Line (ISTL) is an eastward - dip of reverse fault which strikes N-S along the western margin of the NFM. The vertical displacement rate of ISTL is estimated to be maximum 9 mm/yr from the offset amount and the formation age of flexure scarp which appeared in the fluvial terrace [ex. Ikeda et al., (2002)]. Besides, the last event and the reccurrence interval are presumed to be about about 1,500 years aga and 2,000 years, respectively [Okumura (2001)]. In addition the western margin fault of the Nagano basin (NBF) strikes NNE-SSW along the east edge of NFM. The NBF is an eastward-dip of reverse fault, and the Zenkoji earthquake (M7.4) in 1847 was occurred. The purpose of present study is to discuss the geometry of ISTL and geological process of NFM based on the geomorphological and geological survey using the geological dip and strike already obtained at the more than 1,500 data points. Based on these geological data, the geological structure provinceis divided into two types those are a tilt block and a folding belt at west and east sides, respectively. The Western tilting block and an Eastern folding belt trend NS strike and NNE-SSW strike, respectively. As a result of the geomorphic decipherment in alignment with ISTL using the air photograph, flexure scarp of east side upheaval is formed in the fluvial terrace side and it is difficult for the terrace riser which crosses flexure scarp and a valley to observe lateral offset. The tilt block,

  8. Dosimetry and field matching for radiotherapy to the breast and superclavicular fossa

    NASA Astrophysics Data System (ADS)

    Winfield, Elizabeth

    Radiotherapy for early breast cancer aims to achieve local disease control and decrease loco-regional recurrence rates. Treatment may be directed to breast or chest wall alone or, include regional lymph nodes. When using tangential fields to treat the breast a separate anterior field directed to the axilla and supraclavicular fossa (SCF) is needed to treat nodal areas. The complex geometry of this region necessitates matching of adjacent radiation fields in three dimensions. The potential exists for zones of overdosage or underdosage along the match line. Cosmetic results may be compromised if treatment fields are not accurately aligned. Techniques for field matching vary between centres in the UK. A study of dosimetry across the match line region using different techniques, as reported in the multi-centre START Trial Quality Assurance (QA) programme, was undertaken. A custom-made anthropomorphic phantom was designed to assess dose distribution in three dimensions using film dosimetry. Methods with varying degrees of complexity were employed to match tangential and SCF beams. Various techniques combined half beam blocking and machine rotations to achieve geometric alignment. Matching of asymmetric beams allowed a single isocentre technique to be used. Where field matching was not undertaken a gap between tangential and SCF fields was employed. Results demonstrated differences between techniques in addition to variations within the same technique between different centres. Geometric alignment techniques produced more homogenous dose distributions in the match region than gap techniques or those techniques not correcting for field divergence. For this multi-centre assessment of match plane techniques film dosimetry used in conjunction with a breast shaped phantom provided relative dose information. This study has highlighted the difficulties of matching treatment fields to achieve homogenous dose distribution through the region of the match plane and the degree of

  9. The Vindija Neanderthal scapular glenoid fossa: comparative shape analysis suggests evo-devo changes among Neanderthals.

    PubMed

    Di Vincenzo, Fabio; Churchill, Steven E; Manzi, Giorgio

    2012-02-01

    Although the shape of the scapular glenoid fossa (SGF) may be influenced by epigenetic and developmental factors, there appears to be strong genetic control over its overall form, such that variation within and between hominin taxa in SGF shape may contain information about their evolutionary histories. Here we present the results of a geometric morphometric study of the SGF of the Neanderthal Vi-209 from Vindjia Cave (Croatia), relative to samples of Plio-Pleistocene, later Pleistocene, and recent hominins. Variation in overall SGF shape follows a chronological trend from the plesiomorphic condition seen in Australopithecus to modern humans, with pre-modern species of the genus Homo exhibiting intermediate morphologies. Change in body size across this temporal series is not linearly directional, which argues against static allometry as an explanation. However, life history and developmental rates change directionally across the series, suggesting an ontogenetic effect on the observed changes in shape (ontogenetic allometry). Within this framework, the morphospace occupied by the Neanderthals exhibits a discontinuous distribution. The Vindija SGF and those of the later Near Eastern Neanderthals (Kebara and Shanidar) approach the modern condition and are somewhat segregated from both northwestern European (Neandertal and La Ferrassie) and early Mediterranean Neanderthals (Krapina and Tabun). Although more than one scenario may account for the pattern seen in the Neanderthals, the data is consistent with palaeogenetic evidence suggesting low levels of gene flow between Neanderthals and modern humans in the Near East after ca. 120-100 ka (thousands of years ago) (with subsequent introgression of modern human alleles into eastern and central Europe). Thus, in keeping with previous analyses that document some modern human features in the Vindija Neanderthals, the Vindija G(3) sample should not be seen as representative of 'classic'--that is, unadmixed, pre

  10. Evidence for Recent Liquid Water on Mars: Gullies in Sirenum Fossae Trough

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This mosaic of two Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) images shows about 20 different gullies coming down the south-facing wall of a trough in the Sirenum Fossae/Gorgonum Chaos region of the martian southern hemisphere. Each channel and its associated fan--or apron--of debris appears to have started just below the same hard, resistant layer of bedrock located approximately 100 meters (about 325 feet) below the top of the trough wall. The layer beneath this hard, resistant bedrock is interpreted to be permeable, which allows ground water to percolate through it and--at the location of this trough--seep out onto the martian surface. The channels and aprons only occur on the south-facing slope of this valley created by faults on each side of the trough. The depression is approximately 1.4 km (0.9 mi) across.

    The mosaic was constructed from two pictures taken on September 16, 1999, and May 1, 2000. The black line is a gap between the two images that was not covered by MOC. The scene covers an area approximately 5.5 kilometers (3.4 miles) wide by 4.9 km (3.0 mi) high. Sunlight illuminates the area from the upper left. The image is located near 38.5oS, 171.3oW. MOC high resolution images are taken black-and-white (grayscale); the color seen here has been synthesized from the colors of Mars observed by the MOC wide angle cameras and by the Viking Orbiters in the late 1970s.

  11. Shallow radar (SHARAD) sounding observations of the Medusae Fossae Formation, Mars

    USGS Publications Warehouse

    Carter, L.M.; Campbell, B.A.; Watters, T.R.; Phillips, R.J.; Putzig, N.E.; Safaeinili, A.; Plaut, J.J.; Okubo, C.H.; Egan, A.F.; Seu, R.; Biccari, D.; Orosei, R.

    2009-01-01

    The SHARAD (shallow radar) sounding radar on the Mars Reconnaissance Orbiter detects subsurface reflections in the eastern and western parts of the Medusae Fossae Formation (MFF). The radar waves penetrate up to 580 m of the MFF and detect clear subsurface interfaces in two locations: west MFF between 150 and 155?? E and east MFF between 209 and 213?? E. Analysis of SHARAD radargrams suggests that the real part of the permittivity is ???3.0, which falls within the range of permittivity values inferred from MARSIS data for thicker parts of the MFF. The SHARAD data cannot uniquely determine the composition of the MFF material, but the low permittivity implies that the upper few hundred meters of the MFF material has a high porosity. One possibility is that the MFF is comprised of low-density welded or interlocked pyroclastic deposits that are capable of sustaining the steep-sided yardangs and ridges seen in imagery. The SHARAD surface echo power across the MFF is low relative to typical martian plains, and completely disappears in parts of the east MFF that correspond to the radar-dark Stealth region. These areas are extremely rough at centimeter to meter scales, and the lack of echo power is most likely due to a combination of surface roughness and a low near-surface permittivity that reduces the echo strength from any locally flat regions. There is also no radar evidence for internal layering in any of the SHARAD data for the MFF, despite the fact that tens-of-meters scale layering is apparent in infrared and visible wavelength images of nearby areas. These interfaces may not be detected in SHARAD data if their permittivity contrasts are low, or if the layers are discontinuous. The lack of closely spaced internal radar reflectors suggests that the MFF is not an equatorial analog to the current martian polar deposits, which show clear evidence of multiple internal layers in SHARAD data. ?? 2008 Elsevier Inc.

  12. Posterior cruciate ligament removal contributes to abnormal knee motion during posterior stabilized total knee arthroplasty.

    PubMed

    Cromie, Melinda J; Siston, Robert A; Giori, Nicholas J; Delp, Scott L

    2008-11-01

    Abnormal anterior translation of the femur on the tibia has been observed in mid flexion (20-60 degrees ) following posterior stabilized total knee arthroplasty. The underlying biomechanical causes of this abnormal motion remain unknown. The purpose of this study was to isolate the effects of posterior cruciate ligament removal on knee motion after total knee arthroplasty. We posed two questions: Does removing the posterior cruciate ligament introduce abnormal anterior femoral translation? Does implanting a posterior stabilized prosthesis change the kinematics from the cruciate deficient case? Using a navigation system, we measured passive knee kinematics of ten male osteoarthritic patients during surgery after initial exposure, after removing the anterior cruciate ligament, after removing the posterior cruciate ligament, and after implanting the prosthesis. Passively flexing and extending the knee, we calculated anterior femoral translation and the flexion angle at which femoral rollback began. Removing the posterior cruciate ligament doubled anterior translation (from 5.1 +/- 4.3 mm to 10.4 +/- 5.1 mm) and increased the flexion angle at which femoral rollback began (from 31.2 +/- 9.6 degrees to 49.3 +/- 7.3 degrees). Implanting the prosthesis increased the amount of anterior translation (to 16.1 +/- 4.4 mm), and did not change the flexion angle at which femoral rollback began. Abnormal anterior translation was observed in low and mid flexion (0-60 degrees) after removing the posterior cruciate ligament, and normal motion was not restored by the posterior stabilized prosthesis.

  13. Posterior odontoid process angulation in pediatric Chiari I malformation: an MRI morphometric external validation study.

    PubMed

    Ladner, Travis R; Dewan, Michael C; Day, Matthew A; Shannon, Chevis N; Tomycz, Luke; Tulipan, Noel; Wellons, John C

    2015-08-01

    OBJECT Osseous anomalies of the craniocervical junction are hypothesized to precipitate the hindbrain herniation observed in Chiari I malformation (CM-I). Previous work by Tubbs et al. showed that posterior angulation of the odontoid process is more prevalent in children with CM-I than in healthy controls. The present study is an external validation of that report. The goals of our study were 3-fold: 1) to externally validate the results of Tubbs et al. in a different patient population; 2) to compare how morphometric parameters vary with age, sex, and symptomatology; and 3) to develop a correlative model for tonsillar ectopia in CM-I based on these measurements. METHODS The authors performed a retrospective review of 119 patients who underwent posterior fossa decompression with duraplasty at the Monroe Carell Jr. Children's Hospital at Vanderbilt University; 78 of these patients had imaging available for review. Demographic and clinical variables were collected. A neuroradiologist retrospectively evaluated preoperative MRI examinations in these 78 patients and recorded the following measurements: McRae line length; obex displacement length; odontoid process parameters (height, angle of retroflexion, and angle of retroversion); perpendicular distance to the basion-C2 line (pB-C2 line); length of cerebellar tonsillar ectopia; caudal extent of the cerebellar tonsils; and presence, location, and size of syringomyelia. Odontoid retroflexion grade was classified as Grade 0, > 90°; Grade I,85°-89°; Grade II, 80°-84°; and Grade III, < 80°. Age groups were defined as 0-6 years, 7-12 years, and 13-17 years at the time of surgery. Univariate and multivariate linear regression analyses, Kruskal-Wallis 1-way ANOVA, and Fisher's exact test were performed to assess the relationship between age, sex, and symptomatology with these craniometric variables. RESULTS The prevalence of posterior odontoid angulation was 81%, which is almost identical to that in the previous report

  14. Fundus autofluorescence imaging in posterior uveitis.

    PubMed

    Durrani, Khayyam; Foster, C Stephen

    2012-01-01

    Although the phenomenon of fundus autofluorescence has been known for decades, it has only recently been recognized as a measure of retinal pigment epithelial function and health. Characteristic fundus autofluorescence patterns have been described in eyes affected by inflammation of the posterior segment, and these patterns have provided insights into the pathogenesis of posterior uveitis entities. In addition, preliminary data indicate that fundus autofluorescence characteristics may serve as markers of disease activity, allow prediction of visual prognosis, and may help determine the adequacy of therapy. We provide an overview of the current state of fundus autofluorescence imaging technology and review our current knowledge of fundus autoflourescence findings and their clinical use in the posterior uveitis entities.

  15. Reversible cortical blindness: posterior reversible encephalopathy syndrome.

    PubMed

    Bandyopadhyay, Sabyasachi; Mondal, Kanchan Kumar; Das, Somnath; Gupta, Anindya; Biswas, Jaya; Bhattacharyya, Subir Kumar; Biswas, Gautam

    2010-11-01

    Cortical blindness is defined as visual failure with preserved pupillary reflexes in structurally intact eyes due to bilateral lesions affecting occipital cortex. Bilateral oedema and infarction of the posterior and middle cerebral arterial territory, trauma, glioma and meningioma of the occipital cortex are the main causes of cortical blindness. Posterior reversible encephalopathy syndrome (PRES) refers to the reversible subtype of cortical blindness and is usually associated with hypertension, diabetes, immunosuppression, puerperium with or without eclampsia. Here, 3 cases of PRES with complete or partial visual recovery following treatment in 6-month follow-up are reported.

  16. Posterior cortical atrophy: a brief review.

    PubMed

    Kirshner, Howard S; Lavin, Patrick J M

    2006-11-01

    Posterior cortical atrophy is a striking clinical syndrome in which a dementing illness begins with visual symptoms. Initially, the problem may seem to be loss of elementary vision, but over time the patient develops features of visual agnosia, topographical difficulty, optic ataxia, simultanagnosia, ocular apraxia (Balint's syndrome), alexia, acalculia, right-left confusion, and agraphia (Gerstmann's syndrome), and later a more generalized dementia. Occasional patients have visual hallucinations and signs of Parkinson's disease or Lewy body dementia. A number of different neuropathologic disorders are associated with posterior cortical atrophy.

  17. Young Debris Flows of Elysium Fossae and Utopia Planitia, Mars: Implications for Eruptive Sequences, Styles, and Mechanisms

    NASA Astrophysics Data System (ADS)

    Skinner, J. A.; Tanaka, K. L.

    2001-05-01

    Late-stage volcanic activity along the northwest flank of the Elysium volcanic construct deposited a variably fluidized sequence of channelized debris flows, in some cases >1500 km long, into Utopia Planitia. Using integrated imagery and topographic datasets, we have re-examined the stratigraphic relationships of these channelized deposits to help elucidate their history and evolution. Source troughs and chaotic depressions developed from differential heating along distributed patterns of pre-existing structures. Concentrated heating and intrusion along these structures caused collapse and mobilization of debris into laharic flows. Volumetric comparisons suggest that depressions within source terrains (Elysium Fossae and Galaxias Chaos/Fossae) inadequately account for the deposit volume. Though the volumes removed from the flanks of Elysium Mons regionally exceed 104 km3, the channelized deposits comprise >6x104 km3 as determined by cut/fill relations. These comparisons suggest the incorporation of substantial amounts of juvenile volcanic material while the lengthy run-out, smooth floors, and lobate terminations within the channelized deposits point to emplacement of highly fluidized debris. We are currently investigating the supplying relationships between the relatively shallow ( ~300 meters) northern source fossae and chaos and the topographically unconnected and considerably deeper troughs ( ~3000 meters) of Elysium Fossae in the south. We recognize subtle variations in morphologic styles between the southern and northern channelized flow deposits. Both deposits display extensive smooth medial floors bound by higher standing rugged terrains, which apparently acted as constructional "levees" constricting distribution into Utopia Planitia. However, potential pseudocraters, "softened" terrain, and discontinuous elevated channels suggest that the northern flows incorporated more volatile material and/or were emplaced upon volatile rich terrains. Regionally, the

  18. Treatment rationale of fractured posterior teeth.

    PubMed

    Silvestri, A R; Singh, I

    1978-11-01

    The four types of fractures most frequently encountered in posterior teeth--obliquely directed complete fractures, vertically directed complete fractures, obliquely directed incomplete fractures, and vertically directed incomplete fractures--have been described. A detailed treatment approach for each type has been presented.

  19. Posterior Predictive Model Checking in Bayesian Networks

    ERIC Educational Resources Information Center

    Crawford, Aaron

    2014-01-01

    This simulation study compared the utility of various discrepancy measures within a posterior predictive model checking (PPMC) framework for detecting different types of data-model misfit in multidimensional Bayesian network (BN) models. The investigated conditions were motivated by an applied research program utilizing an operational complex…

  20. Posterior Probabilities for a Consensus Ordering.

    ERIC Educational Resources Information Center

    Fligner, Michael A.; Verducci, Joseph S.

    1990-01-01

    The concept of consensus ordering is defined, and formulas for exact and approximate posterior probabilities for consensus ordering are developed under the assumption of a generalized Mallows' model with a diffuse conjugate prior. These methods are applied to a data set concerning 98 college students. (SLD)

  1. Complicated posterior capsulorhexis: aetiology, management, and outcome

    PubMed Central

    Van Cauwenberge, F.; Rakic, J.; Galand, A.

    1997-01-01

    BACKGROUND—A 1 year retrospective analysis of 650 patients, who underwent a posterior capsulorhexis on their intact capsules, was performed to examine the incidence of complications, their aetiologies, and the outcome.
METHODS—Data were analysed on 32 patients with complicated capsulorhexis for type of surgery, preoperative and postoperative factors, and relative risk factors for vitreous issue.
RESULTS—There were six patients with vitreous loss. The posterior capsulorhexis was uncontrolled in 14 cases and difficult to perform in 12 cases. Implantation into the capsular bag was possible in all cases. Systemic vascular hazard and old age (over 80 years) were found to be statistically significant risk factors for vitreous loss (p=0.002 and p=0.03 respectively). The mean follow up was 13.5 months (range 4-25 months). One patient developed a retinal detachment and two had a transient clinical cystoid macular oedema. Visual acuity of ≥ 20/40 was obtained in 93% of the patients.
CONCLUSION—Loss of control of the posterior capsulorhexis has a low incidence but can lead to serious problems during surgery. A good knowledge of the technique is necessary to complete the procedure with a posterior capsulorhexis of the optimum size without vitreous loss.

 PMID:9135382

  2. Subspecialization in the human posterior medial cortex

    PubMed Central

    Bzdok, Danilo; Heeger, Adrian; Langner, Robert; Laird, Angela R.; Fox, Peter T.; Palomero-Gallagher, Nicola; Vogt, Brent A.; Zilles, Karl; Eickhoff, Simon B.

    2014-01-01

    The posterior medial cortex (PMC) is particularly poorly understood. Its neural activity changes have been related to highly disparate mental processes. We therefore investigated PMC properties with a data-driven exploratory approach. First, we subdivided the PMC by whole-brain coactivation profiles. Second, functional connectivity of the ensuing PMC regions was compared by task-constrained meta-analytic coactivation mapping (MACM) and task-unconstrained resting-state correlations (RSFC). Third, PMC regions were functionally described by forward/reverse functional inference. A precuneal cluster was mostly connected to the intraparietal sulcus, frontal eye fields, and right temporo-parietal junction; associated with attention and motor tasks. A ventral posterior cingulate cortex (PCC) cluster was mostly connected to the ventromedial prefrontal cortex and middle left inferior parietal cortex (IPC); associated with facial appraisal and language tasks. A dorsal PCC cluster was mostly connected to the dorsomedial prefrontal cortex, anterior/posterior IPC, posterior midcingulate cortex, and left dorsolateral prefrontal cortex; associated with delay discounting. A cluster in the retrosplenial cortex was mostly connected to the anterior thalamus and hippocampus. Furthermore, all PMC clusters were congruently coupled with the default mode network according to task-constrained but not task-unconstrained connectivity. We thus identified distinct regions in the PMC and characterized their neural networks and functional implications. PMID:25462801

  3. Fuchs's heterochromic cyclitis and posterior capsulotomy.

    PubMed Central

    Roussel, T J; Coster, D J

    1985-01-01

    We report a case of intractable glaucoma following an uncomplicated secondary posterior capsulotomy in a 48-year-old male with Fuchs's heterochromic cyclitis. The patient had been free of inflammation and glaucoma since cataract extraction 27 years previously. We also report the results of phenotypic analysis of lymphocytes removed from the anterior chamber. Images PMID:3859323

  4. Posterior dislocation of the shoulder in athletes.

    PubMed

    Samilson, R L; Prieto, V

    1983-07-01

    Although posterior dislocation of the shoulder is a rare injury in athletes, failure to recognize and properly manage acute dislocation may have serious consequences. The article discusses the incidence, mechanism of injury, classification, pathologic findings, clinical and radiologic diagnosis, and management.

  5. A New Method to Explore the Spectral Impact of the Piriform Fossae on the Singing Voice: Benchmarking Using MRI-Based 3D-Printed Vocal Tracts

    PubMed Central

    Delvaux, Bertrand; Howard, David

    2014-01-01

    The piriform fossae are the 2 pear-shaped cavities lateral to the laryngeal vestibule at the lower end of the vocal tract. They act acoustically as side-branches to the main tract, resulting in a spectral zero in the output of the human voice. This study investigates their spectral role by comparing numerical and experimental results of MRI-based 3D printed Vocal Tracts, for which a new experimental method (based on room acoustics) is introduced. The findings support results in the literature: the piriform fossae create a spectral trough in the region 4–5 kHz and act as formants repellents. Moreover, this study extends those results by demonstrating numerically and perceptually the impact of having large piriform fossae on the sung output. PMID:25048199

  6. A new method to explore the spectral impact of the piriform fossae on the singing voice: benchmarking using MRI-based 3D-printed vocal tracts.

    PubMed

    Delvaux, Bertrand; Howard, David

    2014-01-01

    The piriform fossae are the 2 pear-shaped cavities lateral to the laryngeal vestibule at the lower end of the vocal tract. They act acoustically as side-branches to the main tract, resulting in a spectral zero in the output of the human voice. This study investigates their spectral role by comparing numerical and experimental results of MRI-based 3D printed Vocal Tracts, for which a new experimental method (based on room acoustics) is introduced. The findings support results in the literature: the piriform fossae create a spectral trough in the region 4-5 kHz and act as formants repellents. Moreover, this study extends those results by demonstrating numerically and perceptually the impact of having large piriform fossae on the sung output.

  7. Retrospective study of the bone morphology in the posterior mandibular region. Evaluation of the prevalence and the degree of lingual concavity and their possible complications

    PubMed Central

    Herranz-Aparicio, Judit; Marques, José; Almendros-Marqués, Nieves

    2016-01-01

    Background In order to choose the appropriate implant size and to prevent complications, an oral surgeon must know the size and shape of the mandible. In the posterior mandibular region, a lingual undercut is often found and could represent a difficulty hard to manage if a lingual or buccal perforation occur. A large series of computed tomography (CT) images of the mandibular first molar was evaluated and the bone morphology, the prevalence and the degree of the lingual concavity in the first molar region were studied. Material and Methods One hundred and fifty-one computed tomography (CT) examinations of patients were retrospectively evaluated to determine anatomical variations in bone morphology in the submandibular fossa region. Results A total of 151 subjects were included, consisting of 64 males (M) (42.4%) and 87 females (F) (57.6%). The under-cut type ridge was present in 64.2% of the cases. The concavity angle was 66.6 ± 8.9° (M) and 71.6 ± 8.4° (F) and the linear concavity depth 4.5 ± 2.3 mm (M) and 3.1 ± 1.7 mm (F) (p>0.05). Conclusions Mandibles with any lingual concavity present a potential increased risk of lingual cortical perforation during implant placement surgery. CT imaging allows characterizing the anatomy of the submandibular fossa and provides other important information for the preoperative assessment of the posterior mandible for dental implants placement. Key words:Anatomy, computed tomography, dental implants, intraoperative complications, mandible, panoramic radiography, radiographic examination. PMID:27694785

  8. Path to the Interpeduncular Fossa: Anatomical Comparison of Endoscopic-Assisted versus Standard Subtemporal Approach

    PubMed Central

    Lamki, Tariq; Salma, Asem; Baidya, Nishanta; Ammirati, Mario

    2012-01-01

    Objective The aim of this study was to assess the assumed advantage of endoscopic assistance to the standard subtemporal approach. The idea was to measure qualitatively and quantitatively visibility versus operability. Design We performed eight subtemporal dissections on four cadaver heads. Our dissections integrated an operating microscope, endoscope, and neuronavigation. Comparison was made between visibility and operability afforded by the microscope alone or by the microscope–endoscope combination. Visibility was recorded as complete or incomplete and was quantified for key structures using linear measurements taken by the navigation system. Operability was determined by whichever maneuvers could be safely and comfortably accomplished in the space afforded. Results From our survey, the structures whose visibility most benefitted from the addition of the endoscope include: contralateral third nerve, posterior perforated substance, mammillary bodies, and contralateral superior cerebellar artery. With regard to quantitative evaluation, we found increased visibility of both basilar artery and posterior cerebral artery. With regard to the operability, no objective advantage was afforded by the addition of the endoscope. Subjectively, the maneuvers were easier to perform while using the endoscope. Conclusion Using the endoscope as an assistance tool during conducting classical subtemporal approach can help in overcome a lot of the classical subtemporal approach limitations. PMID:23905002

  9. Displacement-length relationship of normal faults in Acheron Fossae, Mars: new observations with HRSC.

    NASA Astrophysics Data System (ADS)

    Charalambakis, E.; Hauber, E.; Knapmeyer, M.; Grott, M.; Gwinner, K.

    2007-08-01

    For Earth, data sets and models have shown that for a fault loaded by a constant remote stress, the maximum displacement on the fault is linearly related to its length by d = gamma · l [1]. The scaling and structure is self-similar through time [1]. The displacement-length relationship can provide useful information about the tectonic regime.We intend to use it to estimate the seismic moment released during the formation of Martian fault systems and to improve the seismicity model [2]. Only few data sets have been measured for extraterrestrial faults. One reason is the limited number of reliable topographic data sets. We used high-resolution Digital Elevation Models (DEM) [3] derived from HRSC image data taken from Mars Express orbit 1437. This orbit covers an area in the Acheron Fossae region, a rift-like graben system north of Olympus Mons with a "banana"-shaped topography [4]. It has a fault trend which runs approximately WNW-ESE. With an interactive IDL-based software tool [5] we measured the fault length and the vertical offset for 34 faults. We evaluated the height profile by plotting the fault lengths l vs. their observed maximum displacement (dmax-model). Additionally, we computed the maximum displacement of an elliptical fault scarp where the plane has the same area as in the observed case (elliptical model). The integration over the entire fault length necessary for the computation of the area supresses the "noise" introduced by local topographic effects like erosion or cratering. We should also mention that fault planes dipping 60 degree are usually assumed for Mars [e.g., 6] and even shallower dips have been found for normal fault planes [7]. This dip angle is used to compute displacement from vertical offset via d = h/(h*sinα), where h is the observed topographic step height, and ? is the fault dip angle. If fault dip angles of 30 degree are considered, the displacement differs by 40% from the one of dip angles of 60 degree. Depending on the data

  10. Right and left heart catheterization via an antecubital fossa vein and the radial artery--a prospective study.

    PubMed

    Williams, Paul D; Palmer, Sonny; Judkins, Chris; Gutman, Jack; Whitbourn, Rob; MacIsaac, Andrew; Xu, Bo; Burns, Andrew; Wilson, Andrew

    2014-12-01

    Right heart catheterization has been described via the arm but previous reports have been retrospective, performed for limited indications, and may not give an accurate assessment of the success rate or safety of this technique. We sought to prospectively examine the feasibility and safety of left and right heart catheterization entirely via the arm using the radial artery and an antecubital fossa vein for a broad range of indications. Fifty-eight consecutive procedures were included. Transradial arterial access was successful in 57 patients (98%), right heart catheterization via the antecubital fossa vein was successful in 54 patients (93%) and bilateral catheterization from the arm was achieved in 53 patients (91%). Standard diagnostic catheterization was the most frequent procedure (59%), although thermodilution (6.9%), percutaneous coronary intervention (33%), and coronary sinus sampling (16%) were also performed in selected cases. Compared to a historical cohort of patients undergoing right and left heart catheterization via femoral access, mean procedural time (38 vs 47 minutes; P=.03) and screening time (8.1 vs 11.2 minutes; P<.001) were significantly reduced. There was 1 venous forearm hematoma that was managed conservatively. Right and left heart catheterization can be performed routinely via the arm in a broad range of patients and is associated with reduced procedural and fluoroscopy time as compared to femoral access. This approach can be considered for all patients in whom right and left heart catheterization is planned.

  11. Towards an evidence-based management of right iliac fossa pain in the over 50-year-old patient

    PubMed Central

    Gammeri, E; Catton, A; van Duren, BH; Appleton, SG

    2016-01-01

    Introduction Right iliac fossa pain is a common presenting complaint to general surgery. The differential diagnosis is wide, particularly in the elderly. Computed tomography (CT) is often used in the ‘older’ population, as they have a higher prevalence of acute colonic diverticulitis and colonic neoplasia, both of which should be identified prior to surgery. There is, however, no published evidence to support this practice. Methods We retrospectively reviewed the records of all patients aged over 50 years who presented with right iliac fossa (RIF) pain to a district general hospital. We determined whether tenderness was predominantly right- or left-sided and whether systemic inflammatory response syndrome (SIRS) was present on admission. The use of imaging modalities, their results and, if performed, operative findings were recorded. Results Of 3160 patients identified, 89 met the inclusion criteria. Diagnoses included appendicitis (27%), neoplasia (15%), non-specific abdominal pain (15%) and acute colonic diverticulitis (10%). CT was performed in 82% of patients, with a sensitivity of 97% based on operative findings. Six patients underwent surgery without a scan, two of whom required a change in the planned procedure due to unexpected findings. Conclusions Unless contraindicated, CT scanning should be mandatory in patients aged over 50 years presenting with signs of peritonism in the RIF or lower abdomen. PMID:27269436

  12. A case of symptomatic mass in the right iliac fossa: a Bermuda Triangle which often lies the right diagnosis.

    PubMed

    Panarese, Alessandra; Pironi, Daniele; Pontone, Stefano; Vendettuoli, Maurizio; De Cristofaro, Flaminia; Antonelli, Manila; Romani, Annamaria; Filippini, Angelo

    2014-02-24

    Disease of the iliac fossa can often be accompanied by non-specific symptoms and some of these are exclusively caused by the compression of bulky masses of other neighboring structures. In young women a differential diagnosis is a non trivial task as several possible causes have to be taken into account. Thus, intraligamentary tumors, which are extremely rare finding, are frequently confused with uterus, ovary or intestinal tumors. Even if myomas are the most benign tumors of the female genital tract, broad ligament leiomyomas are an unusual finding in women of reproductive age. These tumors are often asymptomatic until they reach a volume likely to cause symptoms related to the mass pressure. An accurate patient's anamnesis and examination serve as a guide to further examinations. Ultrasound is the first line imaging as it can show ovarian or other pelvic mass and doesn't involve exposure to radiations in young patients, who can be pregnant. We describe the clinical presentation and imaging features of a broad ligament leiomyoma, which presented as an inguinal mass in a patient with a right iliac fossa pain. We also report our diagnostic process performing the differential diagnosis with other potential pathologies of RIF. In these cases, a preoperative disease classification discriminating the benign or malignant tumor nature is closely linked to the proper patient management.

  13. The efficacy of fibrin glue injection in the prostatic fossa on decreasing postoperative bleeding following transurethral resection of prostate

    PubMed Central

    Khorrami, Mohammad Hatef; Tadaion, Farhad; Ghanaat, Iman; Alizadeh, Farshid

    2016-01-01

    Background: To evaluate the efficacy of fibrin glue injection in the prostatic fossa at the end of transurethral resection of prostate (TURP), in decreasing postoperative bleeding in patient with benign prostatic hyperplasia (BPH). Materials and Methods: In this prospective randomized clinical trial, sixty patients with BPH, who were a candidate for TURP, were randomly divided into two equal groups. In the intervention group, 10cc of fibrin glue was injected in the prostatic fossa at the end of the surgery; through a 5 Fr feeding tube attached to Foley catheter and its tip was proximal to the balloon of catheter. The other thirty patients created the control group. Hemoglobin (Hb) level and lower urinary tract symptoms (LUTS) score were recorded before and 6, 24, 48 h, and 5 days after TURP. Results: The mean age of the patients and prostate volumes were comparable between the groups. The mean Hb level before and 6 h after TURP were not different between the two groups, however, 24 and 48 h and 5 days after TURP, there was a significant difference as well as a higher decrease in the mean Hb level of the control group (P = 0.023). The mean LUTS score was not statistically different between the two groups. Conclusion: Fibrin glue injection in the prostatic after TURP reduces postoperative bleeding without any effect on LUTS score in patients with BPH. PMID:27995100

  14. Posterior Wnts Have Distinct Roles in Specification and Patterning of the Planarian Posterior Region

    PubMed Central

    Sureda-Gómez, Miquel; Pascual-Carreras, Eudald; Adell, Teresa

    2015-01-01

    The wnt signaling pathway is an intercellular communication mechanism essential in cell-fate specification, tissue patterning and regional-identity specification. A βcatenin-dependent signal specifies the AP (Anteroposterior) axis of planarians, both during regeneration of new tissues and during normal homeostasis. Accordingly, four wnts (posterior wnts) are expressed in a nested manner in central and posterior regions of planarians. We have analyzed the specific role of each posterior wnt and the possible cooperation between them in specifying and patterning planarian central and posterior regions. We show that each posterior wnt exerts a distinct role during re-specification and maintenance of the central and posterior planarian regions, and that the integration of the different wnt signals (βcatenin dependent and independent) underlies the patterning of the AP axis from the central region to the tip of the tail. Based on these findings and data from the literature, we propose a model for patterning the planarian AP axis. PMID:26556349

  15. Mapping Medusae Fossae Formation materials in the southern highlands of Mars

    NASA Astrophysics Data System (ADS)

    Harrison, S. K.; Balme, M. R.; Hagermann, A.; Murray, J. B.; Muller, J.-P.

    2010-10-01

    The Medusae Fossae Formation (MFF) is an extensive deposit (2.2 × 10 6 km 2, Bradley, B.A., Sakimoto, S.E.H., Frey, H., Zimbelman, J.R. [2002]. J. Geophys. Res. 107, 5058) of wind-eroded material of widely debated origin, which unconformably overlies a considerable area of the crustal dichotomy boundary on Mars. The MFF shows a variety of layering patterns, erosional styles and channel-like forms and has been mapped into five main outcrops and three geological members according to exposure and stratigraphy (Scott, D.H., Tanaka, K.L., 1986. USGS Map I-1802-A; Greeley, R., Guest, J.E., 1987. Map I-1802-B; Zimbelman, J.R., Crown, D., Jenson, D., 1996. Lunar Planet. Sci. XXVII. Abstract #1748.). Away from the three main lobes are numerous outliers of MFF materials. These have mainly been reported in the northern lowlands regions (Keszthelyi, L., Jaeger, W.L., and HiRISE team, 2008. Lunar Planet. Sci. XXXIX. Abstract #2420.) but few studies have examined the possibility of MFF outliers on high ground south of the dichotomy boundary. We have searched Mars Orbiter Camera Narrow Angle (MOC NA) images for outliers in this region. Our observations show that there are many MFF outliers on the southern highlands. The characteristics of the outliers indicate materials which overlie the underlying terrain for they appear widely in dips, craters and topographic lows. The surfaces are typified by yardang fields and have a similar patchy and discontinuous nature to materials of the upper member of the MFF. Most have consistent lineation orientations across the wider area which match the dominant orientation of yardangs in the main MFF outcrops. Furthermore, elevation data shows that the maximum, minimum and mean elevations of these newly discovered outliers are closest to those of the upper member of the MFF. We therefore conclude that these deposits are MFF outliers and that they probably represent remnant upper member material. We suggest that there might be two possible

  16. [Manual rotation of occiput posterior presentation].

    PubMed

    Le Ray, C; Goffinet, F

    2011-10-01

    Delivery in occiput posterior position is associated with a higher risk of cesarean section, operative vaginal delivery and severe perineal tears. We report the technic of manual rotation described by Tarnier and Chantreuil and used daily in our maternity center. Only five studies were published on this topic; all of them demonstrate that manual rotation decreases the risk of cesarean section. Moreover, it could decrease the risk of prolonged second stage, chorioamnionitis and third and fourth degree tears in comparison with expectant management. However, manual rotation is associated with a two-fold higher risk of cervical and vaginal lacerations. Manual rotation performed with an adequate technic is an efficient and safe manœuvre to avoid complications associated with occiput posterior vaginal delivery.

  17. Acute traumatic posterior elbow dislocation in children.

    PubMed

    Lieber, Justus; Zundel, Sabine M; Luithle, Tobias; Fuchs, Jörg; Kirschner, Hans-Joachim

    2012-09-01

    Traumatic posterior dislocation of the elbow is often associated with significant morbidity and incomplete recovery. The aim of this study was to retrospectively analyse the outcome of 33 children (median age 10.8 years). Patients underwent reduction and assessment of stability under general anaesthesia. Pure dislocations (n=10) were immobilized, whereas unstable fractures (n=23) were stabilized. Refixation of ligaments was performed if stability was not achieved by fracture stabilization alone. Immobilization was continued for 26 (pure dislocations) or 35 days (associated injuries), respectively. Results were excellent (n=9) or good (n=1) after pure dislocation. Results were excellent (n=15), good (n=7) or poor (n=1) in children with associated injuries. Accurate diagnosis, concentric stable reduction of the elbow as well as stable osteosynthesis of displaced fractures are associated with good results in children with acute posterior elbow dislocations.

  18. Posterior tibial nerve lesions in ankle arthroscopy.

    PubMed

    Cugat, Ramon; Ares, Oscar; Cuscó, Xavier; Garcia, Montserrat; Samitier, Gonzalo; Seijas, Roberto

    2008-05-01

    Ankle arthroscopy provides a minimally invasive approach to the diagnosis and treatment of certain ankle disorders. Neurological complications resulting from ankle arthroscopy have been well documented in orthopaedic and podiatric literature. Owing to the superficial location of the ankle joint and the abundance of overlying periarticular neurovascular structures, complications reported in ankle arthroscopy are greater than those reported for other joints. In particular, all reported neurovascular injuries following ankle arthroscopy have been the direct result of distractor pin or portal placement. The standard posteromedial portal has recognized risks because of the proximity of the posterior neurovascular structures. There can be considerable variability in the course of these portals and their proximity to the neurovascular structures. We found one report of intra-articular damage to the posterior tibial nerve as a result of ankle arthroscopy in the English-language literature and we report this paper as a second case described in the literature.

  19. Progressive visual agnosia with posterior cortical atrophy.

    PubMed

    Mizuno, M; Sartori, G; Liccione, D; Battelli, L; Campo, R

    1996-05-01

    A patient of posterior cortical atrophy characterized by early signs of progressive visual agnosia documented by repeated neuropsychological tests, is reported. SPECT and MRI findings showed left unilateral parieto-occipital involvement in the earlier stage. A PET study executed eight months later showed bilateral parieto-occipital hypometabolism, but predominantly in the left hemisphere. This suggests that the degeneration may have developed asymmetrically, progressing from left unilateral to bilateral.

  20. Endoscopic posterior interhemispheric complete corpus callosotomy.

    PubMed

    Sood, Sandeep; Asano, Eishi; Altinok, Deniz; Luat, Aimee

    2016-12-01

    Traditionally corpus callosotomy is done through a craniotomy centered at the coronal suture, with the aid of a microscope. This involves dissecting through the interhemispheric fissure below the falx to reach the corpus callosum. The authors describe a posterior interhemispheric approach to complete corpus callosotomy with an endoscope, which bypasses the need to perform interhemispheric dissection because the falx is generally close to the corpus callosum in this region.

  1. Material Properties of the Posterior Human Sclera☆

    PubMed Central

    Grytz, Rafael; Fazio, Massimo A.; Girard, Michael J.A.; Libertiaux, Vincent; Bruno, Luigi; Gardiner, Stuart; Girkin, Christopher A.; Downs, J. Crawford

    2013-01-01

    To characterize the material properties of posterior and peripapillary sclera from human donors, and to investigate the macro- and micro-scale strains as potential control mechanisms governing mechanical homeostasis. Posterior scleral shells from 9 human donors aged 57–90 years were subjected to IOP elevations from 5 to 45 mmHg and the resulting full-field displacements were recorded using laser speckle interferometry. Eye-specific finite element models were generated based on experimentally measured scleral shell surface geometry and thickness. Inverse numerical analyses were performed to identify material parameters for each eye by matching experimental deformation measurements to model predictions using a microstructure-based constitutive formulation that incorporates the crimp response and anisotropic architecture of scleral collagen fibrils. The material property fitting produced models that fit both the overall and local deformation responses of posterior scleral shells very well. The nonlinear stiffening of the sclera with increasing IOP was well reproduced by the uncrimping of scleral collagen fibrils, and a circumferentially-aligned ring of collagen fibrils around the scleral canal was predicted in all eyes. Macroscopic in-plane strains were significantly higher in peripapillary region then in the mid-periphery. In contrast, the meso- and micro-scale strains at the collagen network and collagen fibril level were not significantly different between regions. The elastic response of the posterior human sclera can be characterized by the anisotropic architecture and crimp response of scleral collagen fibrils. The similar collagen fibril strains in the peripapillary and mid-peripheral regions support the notion that the scleral collagen architecture including the circumpapillary ring of collagen fibrils evolved to establish optimal load bearing conditions at the collagen fibril level. PMID:23684352

  2. Iris fixation of posterior chamber intraocular lenses.

    PubMed

    Yazdani-Abyaneh, Alireza; Djalilian, Ali R; Fard, Masoud Aghsaei

    2016-12-01

    We introduce a technique for iris fixation of a posterior chamber intraocular lens (IOL) in which most of the procedure is done outside the eye. This minimizes intraocular manipulation, maximizes corneal endothelial preservation, and avoids the risk for IOL drop into the vitreous cavity intraoperatively. The IOL is fixated to the most peripheral part of the iris, resulting in a rounder pupil. Sutures are placed at exact positions on the haptics, resulting in a well-centered IOL.

  3. Cervical disc hernia operations through posterior laminoforaminotomy

    PubMed Central

    Yolas, Coskun; Ozdemir, Nuriye Guzin; Okay, Hilmi Onder; Kanat, Ayhan; Senol, Mehmet; Atci, Ibrahim Burak; Yilmaz, Hakan; Coban, Mustafa Kemal; Yuksel, Mehmet Onur; Kahraman, Umit

    2016-01-01

    Objective: The most common used technique for posterolateral cervical disc herniations is anterior approach. However, posterior cervical laminotoforaminomy can provide excellent results in appropriately selected patients with foraminal stenosis in either soft disc prolapse or cervical spondylosis. The purpose of this study was to present the clinical outcomes following posterior laminoforaminotomy in patients with radiculopathy. Materials and Methods: We retrospectively evaluated 35 patients diagnosed with posterolateral cervical disc herniation and cervical spondylosis with foraminal stenosis causing radiculopathy operated by the posterior cervical keyhole laminoforaminotomy between the years 2010 and 2015. Results: The file records and the radiographic images of the 35 patients were assessed retrospectively. The mean age was 46.4 years (range: 34-66 years). Of the patients, 19 were males and 16 were females. In all of the patients, the neurologic deficit observed was radiculopathy. The posterolaterally localized disc herniations and the osteophytic structures were on the left side in 18 cases and on the right in 17 cases. In 10 of the patients, the disc level was at C5-6, in 18 at C6-7, in 2 at C3-4, in 2 at C4-5, in 1 at C7-T1, in 1 patient at both C5-6 and C6-7, and in 1 at both C4-5 and C5-6. In 14 of these 35 patients, both osteophytic structures and protruded disc herniation were present. Intervertebral foramen stenosis was present in all of the patients with osteophytes. Postoperatively, in 31 patients the complaints were relieved completely and four patients had complaints of neck pain and paresthesia radiating to the arm (the success of operation was 88.5%). On control examinations, there was no finding of instability or cervical kyphosis. Conclusion: Posterior cervical laminoforaminotomy is an alternative appropriate choice in both cervical soft disc herniations and cervical stenosis. PMID:27217655

  4. Electrocardiographic diagnosis of remote posterior wall myocardial infarction using unipolar posterior lead V9

    SciTech Connect

    Rich, M.W.; Imburgia, M.; King, T.R.; Fischer, K.C.; Kovach, K.L. )

    1989-09-01

    The accuracy of four electrocardiographic criteria for diagnosing remote posterior myocardial infarction was assessed prospectively in 369 patients undergoing exercise treadmill testing with thallium scintigraphy. Criteria included the following: (1) R-wave width greater than or equal to 0.04 s and R-wave greater than or equal to S-wave in V1; (2) R-wave greater than or equal to S-wave in V2; (3) T-wave voltage in V2 minus V6 greater than or equal to 0.38 mV (T-wave index); (4) Q-wave greater than or equal to 0.04 s in left paraspinal lead V9. Twenty-seven patients (7.3 percent) met thallium criteria for posterior myocardial infarction, defined as a persistent perfusion defect in the posterobase of the left ventricle. Sensitivities for the four criteria ranged from 4 to 56 percent, and specificities ranged from 64 to 99 percent. Posterior paraspinal lead V9 provided the best overall predictive accuracy (94 percent), positive predictive value (58 percent), and ability to differentiate patients with and without posterior myocardial infarction of any single criterion (p less than .0001). Combining the T-wave index with lead V9 further enhanced the diagnostic yield: the sensitivity for detecting posterior infarction by at least one of these criteria was 78 percent, and when both criteria were positive, specificity was 98.5 percent. It is concluded that a single, unipolar posterior lead in the V9 position is superior to standard 12-lead electrocardiographic criteria in diagnosing remote posterior myocardial infarction, and that combining V9 with the T-wave index maximizes the diagnostic yield.

  5. Polygonal ridge networks on Mars: Diversity of morphologies and the special case of the Eastern Medusae Fossae Formation

    NASA Astrophysics Data System (ADS)

    Kerber, Laura; Dickson, James L.; Head, James W.; Grosfils, Eric B.

    2017-01-01

    Polygonal ridge networks, also known as boxwork or reticulate ridges, are found in numerous locations and geological contexts across Mars. Distinguishing the morphologies and geological context of the ridge networks sheds light on their potential as astrobiological and mineral resource sites of interest. The most widespread type of ridge morphology is characteristic of the Nili Fossae and Nilosyrtis region and consists of thin, criss-crossing ridges with a variety of heights, widths, and intersection angles. They are found in ancient Noachian terrains at a variety of altitudes (between -2500 and 2200 m) and geographic locations and are likely to be chemically altered fracture planes or mineral veins. They occur in the same general areas as valley networks and ancient lake basins, but they are not more numerous where these water-related features are concentrated, and can appear in places where th morphologies are absent. Similarly, some of the ridge networks are located near hydrated mineral detections, but there is not a one-to-one correlation. Smaller, light-toned ridges of variable widths have been found in Gale Crater and other rover sites and are interpreted to be smaller versions of the Nili-like ridges, mostly formed by the mineralization of fractures. This type of ridge is likely to be found in many other places on Mars as more high-resolution data become available. Sinus Meridiani contains many flat-topped ridges arranged into quasi-circular patterns. The ridges are eroding from a clay-rich unit, and could be formed by a similar process as the Nili-type ridges, but at a much larger scale and controlled by fractures made through a different process. Hellas Basin is host to a fourth type of ridge morphology consisting of large, thick, light-toned ridges forming regular polygons at several superimposed scales. While still enigmatic, these are most likely to be the result of sediment-filled fractures. The Eastern Medusae Fossae Formation contains large swaths

  6. Geologic Mapping of the Medusae Fossae Formation on Mars (MC-8 SE and MC-23 NW) and the Northern Lowlands of Venus (V-16 and V-15)

    NASA Technical Reports Server (NTRS)

    Zimbelman, J. R.

    2008-01-01

    This report summarizes the status of a mapping project supported by NASA grant NNX07AP42G, funding for which became available on July 18, focusing on the mapping of the Medusae Fossae Formation (MFF) on Mars. The report also briefly discusses the status of maps of Venus and Ascraeus Mons, begun under previous NASA grants but which are still in progress.

  7. Evidence for the episodic erosion of the Medusae Fossae Formation preserved within the youngest volcanic province on Mars

    NASA Astrophysics Data System (ADS)

    Morgan, Gareth A.; Campbell, Bruce A.; Carter, Lynn M.; Plaut, Jeffrey J.

    2015-09-01

    We use orbital SHAllow RADar (SHARAD) sounder data to three-dimensionally visualize the subsurface structure of Elysium Planitia, the youngest volcanic province on Mars. Our results reveal an emplacement history consisting of multiple groups of overlapping lava flow units, originating from different sources. The uniquely complex "radar stratigraphy" of Elysium Planitia, relative to other volcanic regions, requires a distinct mechanism to generate the numerous reflectors observed in SHARAD data. Sedimentary deposits interbedded with successive batches of lava flows could account for the elaborate pattern of reflectors. We infer that widespread, rapidly emplaced material sourced from the enigmatic Medusae Fossae Formation (MFF) creates these sedimentary layers. This implies that episodes of atmospheric activity, perhaps linked with the obliquity of Mars, periodically erode and redeposit material from the MFF across a large region.

  8. Favorable patient reported outcomes following IMRT for early carcinomas of the tonsillar fossa: Results from a symptom assessment study

    PubMed Central

    Gunn, GB; Hansen, CC; Garden, AS; Fuller, CD; Mohamed, ASRM; Morrison, WH; Frank, SJ; Beadle, BM; Phan, J; Chronowski, GM; Sturgis, EM; Lewis, CM; Lu, C; Hutcheson, KA; Mendoza, TR; Cleeland, CS; Rosenthal, DI

    2016-01-01

    Background A questionnaire-based study was conducted to assess long-term patient reported outcomes (PROs) following definitive IMRT-based treatment for early stage carcinomas of the tonsillar fossa. Methods: Participants had received IMRT with or without systemic therapy for squamous carcinoma of the tonsillar fossa (T1-2 and N0-2b) with a minimum follow-up of 2 years. Patients completed a validated head and neck cancer-specific PRO instrument, the MD Anderson Symptom Inventory-Head and Neck module (MDASI-HN). Symptoms were compared between treatment groups of interest and overall symptom burden was evaluated. Results Of 139 participants analyzed, 51% had received ipsilateral neck IMRT, and 62% single modality IMRT alone (no systemic therapy). There were no differences in mean individual symptom and interference ratings for those treated with bilateral versus ipsilateral neck IMRT alone. However, 40% of those treated with bilateral versus 25% of those treated with ipsilateral neck RT alone reported moderate-to-severe levels of dry mouth (p=0.03). Fatigue, numbness/tingling, and constipation were rated more severe for those who had received systemic therapy (p<0.05 for each), but absolute differences were small. Overall, 51% had no more than mild symptom ratings across all 22 symptoms assessed. Conclusions The long-term patient reported symptom profile in this cohort of tonsil cancer survivors treated with definitive IMRT-based treatment showed a majority of patients with no more than mild symptoms, low symptom interference, and provides an opportunity for future comparison studies with other treatment approaches. PMID:26403258

  9. Shallow hydrothermal alteration and permeability changes in pyroclastic deposits: a case study at La Fossa cone (Vulcano island, Italy):

    NASA Astrophysics Data System (ADS)

    Cangemi, Marianna; Madonia, Paolo; Speziale, Sergio; Oliveri, Ygor

    2016-04-01

    La Fossa cone at Vulcano, the southernmost island of the Aeolian volcanic archipelago (Italy), has been characterized by an intense fumarolic activity since its last eruption dated 1888-90. Mineralogical alteration induced by shallow hydrothermal circulation has significantly reduced the permeability of the volcanic products, causing important feedbacks on the circulation of fluids in the shallowest portion of the volcanic edifice. The summit area of the cone is sealed by a quite continuous coating surface, fostering the condensation of hydrothermal fluids inside the volcanic edifice. The combination of fractures and volcano-stratigraphic discontinuities, conveying hydrothermal fluids, makes significant rock volumes prone to slide seaward, as occurred in 1988 during the main unrest experienced by Vulcano island since its last eruption. Similar instability conditions are found over the Forgia Vecchia crater rim area, formed by phreatic activity on the NE flank of the cone, where tensile fracturing and hydrothermal circulation interacts with mutual negative feedbacks. In the behalf of the DPC-INGV V3 Project 2012-15 we investigated the mineralogical composition and the hydraulic conductivity (under saturated conditions) of volcanic deposits potentially prone to hydrothermal fluid circulation, for evaluating their ability in retaining water, creating favourable conditions for gravitational instability. We also measured rainfall rate and volumetric soil moisture content in two automated stations located in different areas, with and without active hydrothermal circulation. We found that hydrothermal alteration transforms volcanic products into clay minerals, significantly reducing permeability of volcanic deposits. Argillified volcanic materials show background water contents, modulated by impulsive increments following rainfalls, higher than unaltered pyroclastic deposits, due to the combination of lower permeability and direct condensation of hydrothermal vapour. The

  10. Posterior ventricular anchoring neochordal repair of degenerative mitral regurgitation efficiently remodels and repositions posterior leaflet prolapse†

    PubMed Central

    Woo, Y. Joseph; MacArthur, John W.

    2013-01-01

    OBJECTIVES Mitral valve repair techniques for degenerative disease typically entail leaflet resection or neochordal construction, which may require extensive resection, leaflet detachment/reattachment, reliance on diseased native chords or precise neochordal measuring. Occasionally, impaired leaflet mobility, reduced coaptation surface and systolic anterior motion (SAM) may result. We describe a novel technique for addressing posterior leaflet prolapse/flail, which both simplifies repair and addresses these issues. METHODS Fifty-four patients (age 62 ± 11 years) with degenerative MR underwent this new repair, 36 of whom minimally-invasively. A CV5 Gore-Tex suture was placed into the posterior left ventricular myocardium underneath the prolapsing segment as an anchor. This suture was then used to imbricate a portion of the prolapsed segment into the ventricle, creating a smooth, broad, non-prolapsed coapting surface on a leaflet with preserved mobility, additional neochordal support and posteriorly positioned enough to preclude SAM. RESULTS Repair was successful in all patients. The mean MR grade was reduced from +3.8 to +0.1 with 50 of 54 patients having zero MR and 4 of the 54 having trace or mild MR. All patients had proper antero-posterior location of the coaptation line of a mean length of 10.2 mm, and preserved posterior leaflet mobility. No patients had SAM or mitral stenosis. All patients were discharged and are currently doing well. CONCLUSION This new technique facilitated efficient single-suture repair of the prolapsed posterior leaflet mitral regurgitation without the need for resection or sliding annuloplasty. It precluded the need for precise neochordal measurement and preserved the leaflet coaptation surface. PMID:23449863

  11. Talar Osteochondroma Fracture Presenting as Posterior Ankle Impingement.

    PubMed

    Ercin, Ersin; Bilgili, Mustafa Gokhan; Gamsizkan, Mehmet; Avsar, Serdar

    2016-05-01

    Osteochondromas are the most common benign bone tumors. They are usually asymptomatic and found incidentally. When symptomatic, the symptoms are usually due to its location and size. Fracture of an osteochondroma presenting as posterior ankle impingement is a rare condition. We describe a 22-year-old man with solitary exostosis who presented with a posterior ankle mass and posterior ankle impingement with 2 years of follow-up. Surgical intervention was the treatment of choice in this patient, and histologic examination revealed a benign osteochondroma. Osteochondromas found in the posterior aspect of the talus can be complicated by fracture due to persistent motion of the ankle. Talar osteochondroma should be included in the differential diagnosis of posterior ankle impingement causes. Posterior talar osteochondromas, especially when a stalk is present, should be treated surgically before it is more complicated by a fracture and posterior ankle impingement.

  12. [Posterior dislocation of the sternoclavicular joint].

    PubMed

    Mäkinen, Tatu; Madanat, Rami; Heinänen, Mikko; Brinck, Tuomas; Pajarinen, Jarkko

    2013-01-01

    Posterior dislocation of the sternoclavicular joint is a rare injury. It can be associated with life-threatening complications. Computed tomography is the imaging modality of choice with which possible associated injuries can be detected. Acute injuries are managed with closed reduction under general anaesthesia. A fracture-dislocation is inherently more unstable than an isolated dislocation. Surgical treatment is advocated in cases of delayed diagnosis or failed closed reduction. With early diagnosis and treatment, the long-term outcome of this injury is good.

  13. Decompression of Posterior Ankle Impingement With Concomitant Anterior Ankle Pathology by Posterior Ankle Arthroscopy in the Supine Position.

    PubMed

    Lui, Tun Hing

    2016-10-01

    Posterior ankle endoscopy is a safe and effective approach for treatment of posterior ankle impingement. This is usually performed with the patient in prone position. The purpose of this technical note is to describe an arthroscopic approach of decompression of posterior ankle impingement with the patient in supine position. This is indicated if there is posterior ankle impingement together with other ankle pathology requiring anterior ankle arthroscopy. This approach allows treatment of both anterior ankle and posterior ankle pathology with the patient in the supine position. Concomitant anterior ankle arthroscopy can be performed with the usual orientation without the need of change of patient's position.

  14. Traumatic posterior dislocation of hip in children.

    PubMed

    Kutty, S; Thornes, B; Curtin, W A; Gilmore, M F

    2001-02-01

    Traumatic posterior dislocation of the hip joint in children is an uncommon injury. It constitutes a true orthopedic emergency. It makes up over 80% of pediatric hip dislocations. In children, it can occur as a result of minimal trauma, which is attributed to a soft pliable acetabulum and ligamentous laxity. In skeletally mature adolescents, a greater force is required to dislocate the hip joint. Delay in reduction is associated with long-term complications such as avascular necrosis and degenerative arthritis. Avascular necrosis is related to the duration of dislocation. A poorer prognosis is associated with delay in reduction beyond 6 hours, advanced skeletal maturity, or multiple traumas. Prompt reduction minimizes complications. We report two cases of traumatic posterior dislocation of hip in children aged 3 and 14 years. Both were reduced within 6 hours of dislocation, and review at 6 months revealed normal examination and no evidence of any post-traumatic changes. Post-reduction treatment remains without a consensus. This review highlights the clinical presentation, management, and time-sensitive complications of the injury.

  15. Management of an Uncomplicated Posterior Elbow Dislocation

    PubMed Central

    Blackard, Douglas; Sampson, Jo-Ann

    1997-01-01

    Objective: To present a case of an uncomplicated posterior elbow dislocation in a US World Cup athlete and discuss her rehabilitation. Background: Traditional protocol for management of this injury has been splint immobilization for several weeks, but research suggests a shortened duration of immobilization and early active motion. Differential Diagnosis: Elbow dislocation with possible fracture. Treatment: The dislocation was reduced and a compression bandage and sling were applied. The sports medicine staff and athlete determined that rehabilitation would involve limited immobilization with a posterior splint. Also, active range-of- motion exercises were to be incorporated early in the range-of- motion program to decrease pain at the articulation. Uniqueness: The athlete was not immobilized and her aggressive five-phase rehabilitation program progressed according to decrease in inflammation and increase in range of motion and strength. Conclusions: Shortened immobilization and return to World Championship competition 6 weeks postinjury had no longterm adverse effects on the athlete. ImagesFig 1.Fig 2.Fig 3.Fig 4.Fig. 5. PMID:16558436

  16. Posterior malleolar fractures of the ankle.

    PubMed

    Bartoníček, J; Rammelt, S; Tuček, M; Naňka, O

    2015-12-01

    Despite an increasing awareness of injuries to PM in ankle fracture-dislocations, there are still many open questions. The mere presence of a posterior fragment leads to significantly poorer outcomes. Adequate diagnosis, classification and treatment require preoperative CT examination, preferably with 3D reconstructions. The indication for surgical treatment is made individually on the basis of comprehensive assessment of the three-dimensional outline of the PM fracture and all associated injuries to the ankle including syndesmotic instability. Anatomic fixation of the avulsed posterior tibiofibular ligament will contribute to syndesmotic stability and restore the integrity of the incisura tibiae thus facilitating anatomic reduction of the distal fibula. A necessary prerequisite is mastering of posterolateral and posteromedial approaches and the technique of direct reduction and internal fixation. Further clinical studies with higher numbers of patients treated by similar methods and evaluation of pre- and postoperative CT scans will be necessary to determine reliable prognostic factors associated with certain types of PM fractures and associated injuries to the ankle.

  17. Prehension Movements in a Patient (AC) with Posterior Parietal Cortex Damage and Posterior Callosal Section

    ERIC Educational Resources Information Center

    Frak, Victor; Paulignan, Yves; Jeannerod, Marc; Michel, Francois; Cohen, Henri

    2006-01-01

    Prehension movements of the right hand were recorded in a right-handed man (AC), with an injury to the left posterior parietal cortex (PPC) and with a section of the left half of the splenium. The kinematic analysis of AC's grasping movements in direct and perturbed conditions was compared to that of five control subjects. A novel effect in…

  18. GNSS integer ambiguity validation based on posterior probability

    NASA Astrophysics Data System (ADS)

    Wu, Zemin; Bian, Shaofeng

    2015-10-01

    GNSS integer ambiguity validation is considered to be a challenge task for decades. Several kinds of validation tests are developed and widely used in these years, but theoretical basis is their weakness. Ambiguity validation theoretically is an issue of hypothesis test. In the frame of Bayesian hypothesis testing, posterior probability is the canonical standard that statistical decision should be based on. In this contribution, (i) we derive the posterior probability of the fixed ambiguity based on the Bayesian principle and modify it for practice ambiguity validation. (ii) The optimal property of the posterior probability test is proved based on an extended Neyman-Pearson lemma. Since validation failure rate is the issue users most concerned about, (iii) we derive the failure rate upper bound of the posterior probability test, so the user can use the posterior probability test either in the fixed posterior probability or in the fixed failure rate way. Simulated as well as real observed data are used for experimental validations. The results show that (i) the posterior probability test is the most effective within the R-ratio test, difference test, ellipsoidal integer aperture test and posterior probability test, (ii) the posterior probability test is computational efficient and (iii) the failure rate estimation for posterior probability test is useful.

  19. Visual input to the mouse lateral posterior and posterior thalamic nuclei: photoreceptive origins and retinotopic order

    PubMed Central

    Allen, Annette E.; Procyk, Christopher A.; Howarth, Michael; Walmsley, Lauren

    2016-01-01

    Key points The lateral posterior and posterior thalamic nuclei have been implicated in aspects of visually guided behaviour and reflex responses to light, including those dependent on melanopsin photoreception.Here we investigated the extent and basic properties of visually evoked activity across the mouse lateral posterior and posterior thalamus.We show that a subset of retinal projections to these regions derive from melanopsin‐expressing retinal ganglion cells and find many cells that exhibit melanopsin‐dependent changes in firing.We also show that subsets of cells across these regions integrate signals from both eyes in various ways and that, within the lateral posterior thalamus, visual responses are retinotopically ordered. Abstract In addition to the primary thalamocortical visual relay in the lateral geniculate nuclei, a number of other thalamic regions contribute to aspects of visual processing. Thus, the lateral posterior thalamic nuclei (LP/pulvinar) appear important for various functions including determining visual saliency, visually guided behaviours and, alongside dorsal portions of the posterior thalamic nuclei (Po), multisensory processing of information related to aversive stimuli. However, despite the growing importance of mice as a model for understanding visual system organisation, at present we know very little about the basic visual response properties of cells in the mouse LP or Po. Prompted by earlier suggestions that melanopsin photoreception might be important for certain functions of these nuclei, we first employ specific viral tracing to show that a subset of retinal projections to the LP derive from melanopsin‐expressing retinal ganglion cells. We next use multielectrode electrophysiology to demonstrate that LP and dorsal Po cells exhibit a variety of responses to simple visual stimuli including two distinct classes that express melanopsin‐dependent changes in firing (together comprising ∼25% of neurons we recorded). We also

  20. Iodine-125 radiation of posterior uveal melanoma

    SciTech Connect

    Packer, S.

    1987-12-01

    Twenty-eight cases of posterior choroidal melanoma were treated with iodine-125 in gold eye plaques. Eleven cases were located within 3.0 mm of the optic nerve (group A), nine were within 3.0 mm of the fovea (group B), and eight were within 3.0 mm of the optic nerve and fovea (group C). The mean follow-up of group A was 46.3 months; group B, 25.5 months; and group C, 42.7 months. Complications included macular edema, cataract and tumor growth. Visual acuity remained within two lines of that tested preoperatively for 4 of 11 patients in group A, 4 of 9 in group B, and 5 of 8 in group C. These results with iodine-125 suggest it as an appropriate treatment for patients with choroidal melanoma located near optic nerve and/or macula.

  1. Polycythemia causing posterior segment vascular occlusions

    PubMed Central

    Ganesan, Suganeswari; Raman, Rajiv; Sharma, Tarun

    2017-01-01

    A 44-year-old male patient presented with features suggestive of transient central retinal artery occlusion (CRAO) followed by permanent CRAO and lateral posterior ciliary artery occlusion. He had diagnostic features of polycythemia vera (PV). When presented for the first time, the patient had features of ocular ischemia such as ocular pain, conjunctival congestion, and retinal opacification but with normal arm-to-retina time and normal arteriovenous transit time. During the second presentation, he had ocular pain, congested conjunctiva, retinal opacification, cherry red spot with box-carrying of retinal vessels, and choroidal infarct (Amalric's sign). He had lost light perception in that eye. Patients with polycythemia are prone to multifocal vascular occlusions and this can be the presenting feature in PV. A timely diagnosis and prompt management can prevent these repeated thromboembolic occlusive episodes. PMID:28298862

  2. Hemifacial spasm and posterior auricular muscle.

    PubMed

    Kiziltan, M; Sahin, R; Uzun, N; Kiziltan, G

    2006-09-01

    We aimed to investigate to which extent posterior auricular muscle (PAM) was affected and whether it contributed to the reflex activity in hemifacial spasm (HFS) patients. 19 HFS patients' spasm activities were recorded from facial muscles. Spasm activity of PAM was recorded synchronously on the symptomatic side in all patients. Lateral spread of blink reflex to orbicularis oris and PAMs were recorded in all but two patients. Botulinum toxin was applied to the PAM with the 14 patients presenting tinnitus, "clicking" or a "ticking" sound on the sane side and other positive auricular symptoms. After treatment, there was symptomatic improvement in 9 of 14 patients. The patients presenting with auricular symptoms and showing spasm activity in their PAMs can be thought as a candidate for botulinum toxin treatment scheme.

  3. Bladder neck incompetence at posterior urethroplasty

    PubMed Central

    Koraitim, Mamdouh M.

    2015-01-01

    The finding of an incompetent bladder neck (BN) at the time of posterior urethroplasty will necessarily exacerbate the already difficult situation. In such cases the aim of the treatment is not only to restore urethral continuity by end-to-end urethral anastomosis, but also to restore the function of the BN to maintain urinary continence. Fortunately, the incidence of incompetence of the BN at posterior urethroplasty is uncommon, usually ≈4.5%. It seems that pelvic fracture-related BN injuries, in contrast to urethral injuries which result from a shearing force, are due to direct injury by the sharp edge of the fractured and displaced pubic bone. The risk of injuries to the BN is greater in children, in patients with a fracture involving both superior and inferior pubic rami on the same side, and in those managed initially by primary realignment. An incompetent BN is suspected by finding an open rectangular BN on cystography, and a fixedly open BN on suprapubic cystoscopy. An incompetent BN can be treated either subsequent to or concomitant with the urethral repair, according to whether a perineal or a perineo-abdominal urethroplasty is used, respectively. Several options have been reported to treat pelvic fracture-related BN incompetence, including reconstructing the BN, forming a new sphincter by tubularisation of a rectangular flap of the anterior bladder wall, and mechanical occlusion by an artificial sphincter or collagen injection. Reconstruction of the BN by the Young-Dees-Leadbetter∗∗ procedure probably provides the most successful results. PMID:26019982

  4. A branching, positive relief network in the middle member of the Medusae Fossae Formation, equatorial Mars—Evidence for sapping?

    NASA Astrophysics Data System (ADS)

    Harrison, S. K.; Balme, M. R.; Hagermann, A.; Murray, J. B.; Muller, J.-P.; Wilson, A.

    2013-09-01

    The Medusae Fossae Formation (MFF) is a geological formation comprising three geological units (members) spread across five principal lobes. It dominates a quarter of the longitudinal extent of the equatorial region of Mars. Positive relief features referred to as ‘sinuous ridges’ (commonly interpreted as inverted paleoflow channel or valley fills) have been observed in the lowest member of the western MFF, but have not been identified within the central and eastern portions of the formation, in the middle and upper members. This paper presents the identification and analysis of a branching, positive relief system which occurs in the central lobe of the MFF in what appears to be an exposure of the middle member. A simple geomorphological map of the system is presented, from which we have adopted the working hypothesis that this is an inverted fill of a branching fluvial channel or valley system. A suite of morphological and topographic evidence supporting this hypothesis is presented, including analysis of the network using a ∼15 m/pixel digital terrain model derived from a Context Imager (CTX) stereo image pair. The evidence supporting this hypothesis includes: (1) the local slope and topography of the upper surface of the network are consistent with a contributory network; (2) the braided, fan-like form at the termination of the branching network is consistent in morphology with it being a depositional fan at the end of a fluvial system; (3) the terminal fan and surrounding deposits show layering and polygonization; and (4) there is strong association between the lower order branches and amphitheater shaped scarps in the depression walls. We evaluate the possible origins of this fluvial system and suggest that seepage sapping is the most probable. Two possible models for the evolution of the network and related features are presented; both require melt of ice within the MFF to form liquid water. We conclude that at least some portions of the Medusae Fossae

  5. Diagnostics for insufficiencies of posterior calculations in Bayesian signal inference.

    PubMed

    Dorn, Sebastian; Oppermann, Niels; Ensslin, Torsten A

    2013-11-01

    We present an error-diagnostic validation method for posterior distributions in Bayesian signal inference, an advancement of a previous work. It transfers deviations from the correct posterior into characteristic deviations from a uniform distribution of a quantity constructed for this purpose. We show that this method is able to reveal and discriminate several kinds of numerical and approximation errors, as well as their impact on the posterior distribution. For this we present four typical analytical examples of posteriors with incorrect variance, skewness, position of the maximum, or normalization. We show further how this test can be applied to multidimensional signals.

  6. Shape variability of the adult human acetabulum and acetabular fossa related to sex and age by geometric morphometrics. Implications for adult age estimation.

    PubMed

    San-Millán, Marta; Rissech, Carme; Turbón, Daniel

    2017-03-01

    This study aims to explore shape variability of the acetabulum during the human adult life span, in relation to sex and age. The human acetabular shape was analysed in 682 os coxae from three different documented skeletal collections from the Iberian Peninsula. Two landmarks and thirty-two sliding semi-landmarks were used for the geometric morphometric procedures and a clock-wise standard was used for orientation. The 180° meridian (6:00) line was positioned over the midpoint of the acetabular notch and 36 reference points in 10° increments along the rim were marked. Data showed that size, sex and age significantly influence acetabular shape variation. Sex differences were significant in individuals younger than 65 years old and were characterised by males exhibiting relatively extended acetabular rim profiles from 10:00 to 1:00, narrower acetabular notches, and reduced acetabular fossae. In addition, three main age-related changes occurred to the acetabular shape in both sexes: outer acetabular profile modification, with extension from 10:00 to 1:00 and reduction from 7:00 to 9:00, acetabular notch narrowing, and acetabular fossa reduction. The age-related changes that were observed are shared by both sexes and seem to be related to bone production associated with age. Specifically, age appears to affect the entire border of the lunate surface: the acetabular rim, both acetabular horns, and the outer edge of the acetabular fossa. Furthermore, shape data confirmed the clover-leaf shape of the acetabular fossa in both males and females. These results improve our understanding of acetabular shape, and assist in refining age-estimation methods and enhancing hip surgery and rehabilitation.

  7. Identification of hydrated silicate minerals on Mars using MRO-CRISM: Geologic context near Nili Fossae and implications for aqueous alteration

    USGS Publications Warehouse

    Ehlmann, B.L.; Mustard, J.F.; Swayze, G.A.; Clark, R.N.; Bishop, J.L.; Poulet, F.; Des Marais, D.J.; Roach, L.H.; Milliken, R.E.; Wray, J.J.; Barnouin-Jha, O.; Murchie, S.L.

    2009-01-01

    The Noachian terrain west of the Isidis basin hosts a diverse collection of alteration minerals in rocks comprising varied geomorphic units within a 100,000 km2 region in and near the Nili Fossae. Prior investigations in this region by the Observatoire pour l'Min??ralogie, l'Eau, les Glaces, et l'Activit?? (OMEGA) instrument on Mars Express revealed large exposures of both mafic minerals and iron magnesium phyllosilicates in stratigraphic context. Expanding on the discoveries of OMEGA, the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) aboard the Mars Reconnaissance Orbiter (MRO) has found more spatially widespread and mineralogically diverse alteration minerals than previously realized, which represent multiple aqueous environments. Using CRISM near-infrared spectral data, we detail the basis for identification of iron and magnesium smectites (including both nontronite and more Mg-rich varieties), chlorite, prehnite, serpentine, kaolinite, potassium mica (illite or muscovite), hydrated (opaline) silica, the sodium zeolite analcime, and magnesium carbonate. The detection of serpentine and analcime on Mars is reported here for the first time. We detail the geomorphic context of these minerals using data from high-resolution imagers onboard MRO in conjunction with CRISM. We find that the distribution of alteration minerals is not homogeneous; rather, they occur in provinces with distinctive assemblages of alteration minerals. Key findings are (1) a distinctive stratigraphy, in and around the Nili Fossae, of kaolinite and magnesium carbonate in bedrock units always overlying Fe/Mg smectites and (2) evidence for mineral phases and assemblages indicative of low-grade metamorphic or hydrothermal aqueous alteration in cratered terrains. The alteration minerals around the Nili Fossae are more typical of those resulting from neutral to alkaline conditions rather than acidic conditions, which appear to have dominated much of Mars. Moreover, the mineralogic

  8. Posterior tibial subluxation and short-term arthritis resulting from failed posterior cruciate ligament reconstruction.

    PubMed

    Mavrodontidis, Alexandros N; Papadonikolakis, Anastasios; Moebius, Ulf G; Gelalis, Ioannis; Motsis, Efstathios; Soucacos, Panayotis N

    2003-01-01

    Posterior tibial subluxations because of combined or isolated posterior cruciate ligament (PCL) injuries require detailed evaluation. PCL reconstructions are difficult procedures because of the low rate of such injuries and the complex anatomy of the ligament. We report on 2 cases of failed PCL reconstruction because of malpositioned femoral tunnels. These 2 cases support the existing biomechanical evidence that the correct placement of the tunnels, especially in the femur, is a major factor in defining the outcome. It seems that the drilling of the tunnels, especially in the femur, during PCL reconstruction must be performed with accuracy and always be evaluated in cases of graft failure. In addition, failed PCL reconstructions are usually accompanied by a short-term excessive arthritis that results in poor functional outcome.

  9. Micro-computed tomography evaluation of the glenoid fossa and mandibular condyle bone after bilateral vertical ramus mandibular distraction in a canine model.

    PubMed

    Sant'Anna, Eduardo Franzotti; Gomez, David F; Sumner, Dale R; Williams, James M; Figueroa, Alvaro A; Ostric, Srdjan A; Theodoru, Spero; Polley, John W

    2006-01-01

    The aim of this study was to quantify bone microarchitecture within the glenoid fossa and mandibular condyle following mandibular distraction osteogenesis. Eight 6- to 9-month-old male beagle dogs underwent bilateral vertical mandibular distraction with semiburied distractors (12 days of distraction at 1 mm per day). One unoperated animal served as control. After distraction the animals were divided into two groups (N = 4) and killed after 1 or 2 months of consolidation. Three-dimensional trabecular architecture was analyzed by micro-computed tomography (muCT). At both sites the overall trends were similar. In the glenoid fossa, there was decreased bone volume, trabecular number, and connectivity density and increased trabecular separation at 1 month and decreased trabecular thickness and increased structure model index compared with the control (P < 0.05). In the mandibular condyle, there was decreased bone volume, trabecular number, and connectivity density at both 1 and 2 months, with decreased trabecular thickness and increased structure model index at 2 months only compared with the control (P < 0.05). The bone became less dense and more rodlike. These bone changes are similar to those seen by the effects of aging or impaired normal function. Thus, in the short term, changes occur in the bone microstructure of the glenoid fossa and mandibular condyle after vertical mandibular ramus distraction in the canine model.

  10. Micro-computed tomography evaluation of the glenoid fossa and mandibular condyle bone after bilateral vertical ramus mandibular distraction in a canine model.

    PubMed

    Sant'Anna, Eduardo Franzotti; Gomez, David F; Sumner, Dale R; Williams, James M; Figueroa, Alvaro A; Ostric, Srdjan A; Theodoru, Spero; Polley, John W

    2006-05-01

    The aim of this study was to quantify bone microarchitecture within the glenoid fossa and mandibular condyle following mandibular distraction osteogenesis. Eight 6- to 9-month-old male beagle dogs underwent bilateral vertical mandibular distraction with semiburied distractors (12 days of distraction at 1 mm per day). One unoperated animal served as control. After distraction the animals were divided into two groups (N = 4) and killed after 1 or 2 months of consolidation. Three-dimensional trabecular architecture was analyzed by micro-computed tomography (microCT). At both sites the overall trends were similar. In the glenoid fossa, there was decreased bone volume, trabecular number, and connectivity density and increased trabecular separation at 1 month and decreased trabecular thickness and increased structure model index compared with the control (P < 0.05). In the mandibular condyle, there was decreased bone volume, trabecular number, and connectivity density at both 1 and 2 months, with decreased trabecular thickness and increased structure model index at 2 months only compared with the control (P < 0.05). The bone became less dense and more rodlike. These bone changes are similar to those seen by the effects of aging or impaired normal function. Thus, in the short term, changes occur in the bone microstructure of the glenoid fossa and mandibular condyle after vertical mandibular ramus distraction in the canine model.

  11. Mechanisms for Olivine Carbonation at the Nili Fossae/Isidis Basin Boundary, Mars: Evidence of Intense Surface Aqueous Activity

    NASA Astrophysics Data System (ADS)

    Mustard, J. F.

    2015-12-01

    One of the most extensive surface deposits of carbonate on Mars is on the slopes of the Isidis Basin rising up to the Nili Fossae region (Ehlmann et al., 2008; Niles et al., 2012; Edwards and Ehlmann 2015). A key factor for the formation of carbonate in this region is the association of carbonate with olivine: this ubiquitous relationship shows the reactants and products are in direct association. There are four clear hypotheses for the geologic environment of formation. 1) Water-rock interaction in the shallow subsurface at slightly elevated temperatures altered olivine to Mg-carbonate perhaps through extended periods of heat and water with burial leading to olivine-serpentine-talc-chlorite alteration pathway (Brown et al., 2010; Viviano et al., 2013). 2) Olivine-rich material, heated by impact or volcanic processes, emplaced on top of a water-bearing phyllosilicate rich unit initiated hydrothermal alteration along the contact. 3) Olivine-rich rocks were weathered to carbonate at surface (cold) temperatures in a manner similar to olivine weathering of meteorites in Antarctica. 4) Carbonate precipitated from shallow ephemeral lakes. These hypotheses are quite different in their predictions of mineral assemblage, water requirements, and habitability. I will show new data and analyses that are providing insights to the question of the mineralogy and assemblages of carbonate-bearing units in the region, diagostic of processes. It is becoming more evident that surface aqueous activity, perhaps involving an extensive cryosphere in the form of Hesperian ice sheets.

  12. Medusae Fossae-Elysium Region, Mars: Depression in the HEND/Odyssey Map of Mars Epithermal Neutrons

    NASA Technical Reports Server (NTRS)

    Ivanov, M. A.; Litvak, M. L.; Mitrofanov, I. G.; Boynton, W.; Saunders, R. S.

    2003-01-01

    The first data from the Gamma Ray Spectrometer (GRS) onboard Mars Odyssey spacecraft showed that the low neutron fluxes characterize both subpolar regions of Mars. The low neutron fluxes mean the presence of hydrogen-rich soils and have been interpreted as an indication on abundant water ice in these areas. The equatorial region of Mars (equatorward of approx. 50 deg) is characterized by higher fluxes of both epithermal (0.4 eV-100 keV, come from depth 1-2 m) and fast (3.4-7.3 MeV, come from depth 0.2-0.3 m) neutrons meaning that this area is mostly dry. The pattern of distribution of the neutron fluxes is in a good agreement with the theoretical predictions on the stability of ground ice on present Mars. The actual distribution of the ice, however, depends on variations of thermal inertia of soils and albedo of the surface. The flux of the epithermal neutrons detected by the HEND instrument, which is part of GRS, has two noticeable depressions in the equatorial region, one in Arabia Terra and another in the Medusae Fossae-Elysium region (MFER). Here we present the initial results of analysis of characteristics of the neutron fluxes and regional geological setting of the epithermal neutron depression in this area. The main goal of our study was to put some constraints on the time of the anomaly formation and to assess possible form of hydrogen (ground ice vs. chemically bound water) there.

  13. The relation of catastrophic flooding of Mangala Valles, Mars, to faulting of memnonia fossae and Tharsis volcanism

    USGS Publications Warehouse

    Tanaka, K.L.; Chapman, M.G.

    1990-01-01

    Detailed stratigraphic relations indicate two coeval periods of catastrophic flooding and Tharsis-centered faulting (producing Memnonia Fossae) in the Mangala Valles region of Mars. Major sequences of lava flows of the Tharsis Montes Formation and local, lobate plains flows were erupted during and between these channeling and faulting episodes. First, Late Hesperian channel development overlapped in time the Tharsis-centered faulting that trends north 75?? to 90??E. Next, Late Hesperian/Early Amazonian flooding was coeval with faulting that trends north 55?? to 70??E. In some reaches, resistant lava flows filled the early channels, resulting in inverted channel topography after the later flooding swept through. Both floods likely originated from the same graben, which probably was activated during each episode of faulting. Faulting broke through groundwater barriers and tapped confined aquifers in higher regions west and east of the point of discharge. The minimum volume of water required to erode Mangala Valles (about 5 ?? 1012 m3) may have been released through two floods that drained a few percent pore volume from a relatively permeable aquifer. The peak discharges may have been produced by hydrothermal groundwater circulation induced by Tharsis magmatism, tectonic uplift centered at Tharsis Montes, and compaction of saturated crater ejecta due to loading by lava flows. -Authors

  14. Posterior regeneration in Isodiametra pulchra (Acoela, Acoelomorpha)

    PubMed Central

    2013-01-01

    Introduction Regeneration is a widespread phenomenon in the animal kingdom, but the capacity to restore damaged or missing tissue varies greatly between different phyla and even within the same phylum. However, the distantly related Acoelomorpha and Platyhelminthes share a strikingly similar stem-cell system and regenerative capacity. Therefore, comparing the underlying mechanisms in these two phyla paves the way for an increased understanding of the evolution of this developmental process. To date, Isodiametra pulchra is the most promising candidate as a model for the Acoelomorpha, as it reproduces steadily under laboratory conditions and is amenable to various techniques, including the silencing of gene expression by RNAi. In order to provide an essential framework for future studies, we report the succession of regeneration events via the use of cytochemical, histological and microscopy techniques, and specify the total number of cells in adult individuals. Results Isodiametra pulchra is not capable of regenerating a new head, but completely restores all posterior structures within 10 days. Following amputation, the wound closes via the contraction of local muscle fibres and an extension of the dorsal epidermis. Subsequently, stem cells and differentiating cells invade the wound area and form a loosely delimited blastema. After two days, the posterior end is re-patterned with the male (and occasionally the female) genital primordium being apparent. Successively, these primordia differentiate into complete copulatory organs. The size of the body and also of the male and female copulatory organs, as well as the distance between the copulatory organs, progressively increase and by nine days copulation is possible. Adult individuals with an average length of 670 μm consist of approximately 8100 cells. Conclusion Isodiametra pulchra regenerates through a combination of morphallactic and epimorphic processes. Existing structures are “re-modelled” and provide a

  15. Paratrooper's Ankle Fracture: Posterior Malleolar Fracture

    PubMed Central

    Young, Ki Won; Cho, Jae Ho; Kim, Hyung Seuk; Cho, Hun Ki; Lee, Kyung Tai

    2015-01-01

    Background We assessed the frequency and types of ankle fractures that frequently occur during parachute landings of special operation unit personnel and analyzed the causes. Methods Fifty-six members of the special force brigade of the military who had sustained ankle fractures during parachute landings between January 2005 and April 2010 were retrospectively analyzed. The injury sites and fracture sites were identified and the fracture types were categorized by the Lauge-Hansen and Weber classifications. Follow-up surveys were performed with respect to the American Orthopedic Foot and Ankle Society ankle-hindfoot score, patient satisfaction, and return to preinjury activity. Results The patients were all males with a mean age of 23.6 years. There were 28 right and 28 left ankle fractures. Twenty-two patients had simple fractures and 34 patients had comminuted fractures. The average number of injury and fractures sites per person was 2.07 (116 injuries including a syndesmosis injury and a deltoid injury) and 1.75 (98 fracture sites), respectively. Twenty-three cases (41.07%) were accompanied by posterior malleolar fractures. Fifty-five patients underwent surgery; of these, 30 had plate internal fixations. Weber type A, B, and C fractures were found in 4, 38, and 14 cases, respectively. Based on the Lauge-Hansen classification, supination-external rotation injuries were found in 20 cases, supination-adduction injuries in 22 cases, pronation-external rotation injuries in 11 cases, tibiofibular fractures in 2 cases, and simple medial malleolar fractures in 2 cases. The mean follow-up period was 23.8 months, and the average follow-up American Orthopedic Foot and Ankle Society ankle-hindfoot score was 85.42. Forty-five patients (80.36%) reported excellent or good satisfaction with the outcome. Conclusions Posterior malleolar fractures occurred in 41.07% of ankle fractures sustained in parachute landings. Because most of the ankle fractures in parachute injuries were

  16. Radial head fracture associated with posterior interosseous nerve injury.

    PubMed

    Terra, Bernardo Barcellos; Sassine, Tannus Jorge; Lima, Guilherme de Freitas; Rodrigues, Leandro Marano; Padua, David Victoria Hoffmann; Nadai, Anderson de

    2016-01-01

    Fractures of the radial head and radial neck correspond to 1.7-5.4% of all fractures and approximately 30% may present associated injuries. In the literature, there are few reports of radial head fracture with posterior interosseous nerve injury. This study aimed to report a case of radial head fracture associated with posterior interosseous nerve injury.

  17. Wnt signaling and the evolution of embryonic posterior development.

    PubMed

    Martin, Benjamin L; Kimelman, David

    2009-03-10

    During vertebrate embryogenesis, most of the mesodermal tissue posterior to the head forms from a progenitor population that continuously adds blocks of muscles (the somites) from the back end of the embryo. Recent work in less commonly studied arthropods--the flour beetle Tribolium and the common house spider--provides evidence suggesting that this posterior growth process might be evolutionarily conserved, with canonical Wnt signaling playing a key role in vertebrates and invertebrates. We discuss these findings as well as other evidence that suggests that the genetic network controlling posterior growth was already present in the last common ancestor of the Bilateria. We also highlight other interesting commonalities as well as differences between posterior growth in vertebrates and invertebrates, suggest future areas of research, and hypothesize that posterior growth may facilitate evolution of animal body plans.

  18. Management of the posterior capsule during pediatric intraocular lens implantation.

    PubMed

    Buckley, E G; Klombers, L A; Seaber, J H; Scalise-Gordy, A; Minzter, R

    1993-06-15

    One of the major obstacles in pediatric intraocular lens implantation has been the subsequent dense opacification of the posterior capsule. We used a modification of the standard pediatric cataract surgical procedure, which involved endocapsular cataract extraction, posterior chamber intraocular lens implantation, pars plana posterior capsulotomy, and pars plana anterior vitrectomy in 20 consecutive patients with unilateral traumatic, radiation-induced, and developmental cataracts. Visual axes were rapidly restored in all patients without further intervention for posterior capsule opacification. Visual acuity returned to 20/40 or better in all patients and 75% of all patients (15 patients) reached maximum improvement by five weeks. No complications attributed to intraoperative removal of the posterior capsule occurred.

  19. New infectious etiologies for posterior uveitis.

    PubMed

    Khairallah, Moncef; Kahloun, Rim; Ben Yahia, Salim; Jelliti, Bechir; Messaoud, Riadh

    2013-01-01

    Emergent and resurgent arthropod vector-borne diseases are major causes of systemic morbidity and death and expanding worldwide. Among them, viral and bacterial agents including West Nile virus, Dengue fever, Chikungunya, Rift Valley fever, and rickettsioses have been recently associated with an array of ocular manifestations. These include anterior uveitis, retinitis, chorioretinitis, retinal vasculitis and optic nerve involvement. Proper clinical diagnosis of any of these infectious diseases is based on epidemiological data, history, systemic symptoms and signs, and the pattern of ocular involvement. The diagnosis is usually confirmed by the detection of a specific antibody in serum. Ocular involvement associated with emergent infections usually has a self-limited course, but it can result in persistent visual impairment. There is currently no proven specific treatment for arboviral diseases, and therapy is mostly supportive. Vaccination for humans against these viruses is still in the research phase. Doxycycline is the treatment of choice for rickettsial diseases. Prevention, including public measures to reduce the number of mosquitoes and personal protection, remains the mainstay for arthropod vector disease control. Influenza A (H1N1) virus was responsible for a pandemic human influenza in 2009, and was recently associated with various posterior segment changes.

  20. Facilitating text reading in posterior cortical atrophy

    PubMed Central

    Rajdev, Kishan; Shakespeare, Timothy J.; Leff, Alexander P.; Crutch, Sebastian J.

    2015-01-01

    Objective: We report (1) the quantitative investigation of text reading in posterior cortical atrophy (PCA), and (2) the effects of 2 novel software-based reading aids that result in dramatic improvements in the reading ability of patients with PCA. Methods: Reading performance, eye movements, and fixations were assessed in patients with PCA and typical Alzheimer disease and in healthy controls (experiment 1). Two reading aids (single- and double-word) were evaluated based on the notion that reducing the spatial and oculomotor demands of text reading might support reading in PCA (experiment 2). Results: Mean reading accuracy in patients with PCA was significantly worse (57%) compared with both patients with typical Alzheimer disease (98%) and healthy controls (99%); spatial aspects of passages were the primary determinants of text reading ability in PCA. Both aids led to considerable gains in reading accuracy (PCA mean reading accuracy: single-word reading aid = 96%; individual patient improvement range: 6%–270%) and self-rated measures of reading. Data suggest a greater efficiency of fixations and eye movements under the single-word reading aid in patients with PCA. Conclusions: These findings demonstrate how neurologic characterization of a neurodegenerative syndrome (PCA) and detailed cognitive analysis of an important everyday skill (reading) can combine to yield aids capable of supporting important everyday functional abilities. Classification of evidence: This study provides Class III evidence that for patients with PCA, 2 software-based reading aids (single-word and double-word) improve reading accuracy. PMID:26138948

  1. Automatic quantification of posterior capsule opacification

    NASA Astrophysics Data System (ADS)

    Barman, Sarah A.; Uyyanonvara, Bunyarit; Boyce, James F.; Sanguinetti, Giorgia; Hollick, Emma J.; Meacock, William R.; Spalton, David J.; Paplinski, Andrew P.

    2000-06-01

    After Cataract surgery where a plastic implant lens is implanted into the eye to replace the natural lens, many patients suffer from cell growth across a membrane situated at the back of the lens which degrades their vision. The cell growth is known as Posterior Capsule Opacification (or PCO). It is important to be able to quantify PCO so that the effect of different implant lens types and surgical techniques may be evaluated. Initial results obtained using a neural network to detect PCO from implant lenses are compared to an established but less automated method of detection, which segments the images using texture segmentation in conjunction with co- occurrence matrices. Tests show that the established method performs well in clinical validation and repeatability trials. The requirement to use a neural network to analyze the implant lens images evolved from the analysis of over 1000 images using the established co-occurrence matrix segmentation method. The work shows that a method based on neural networks is a promising tool to automate the procedure of calculating PCO.

  2. Representation of numerosity in posterior parietal cortex

    PubMed Central

    Roitman, Jamie D.; Brannon, Elizabeth M.; Platt, Michael L.

    2012-01-01

    Humans and animals appear to share a similar representation of number as an analog magnitude on an internal, subjective scale. Neurological and neurophysiological data suggest that posterior parietal cortex (PPC) is a critical component of the circuits that form the basis of numerical abilities in humans. Patients with parietal lesions are impaired in their ability to access the deep meaning of numbers. Acalculiac patients with inferior parietal damage often have difficulty performing arithmetic (2 + 4?) or number bisection (what is between 3 and 5?) tasks, but are able to recite multiplication tables and read or write numerals. Functional imaging studies of neurologically intact humans performing subtraction, number comparison, and non-verbal magnitude comparison tasks show activity in areas within the intraparietal sulcus (IPS). Taken together, clinical cases and imaging studies support a critical role for parietal cortex in the mental manipulation of numerical quantities. Further, responses of single PPC neurons in non-human primates are sensitive to the numerosity of visual stimuli independent of low-level stimulus qualities. When monkeys are trained to make explicit judgments about the numerical value of such stimuli, PPC neurons encode their cardinal numerical value; without such training PPC neurons appear to encode numerical magnitude in an analog fashion. Here we suggest that the spatial and integrative properties of PPC neurons contribute to their critical role in numerical cognition. PMID:22666194

  3. [Posterior reversible encephalopathy: beyond the original description].

    PubMed

    Avecillas-Chasín, Josué M; Matías-Guiu, Jordi A; Bautista-Balbás, Luis

    2015-07-16

    Introduccion. La encefalopatia posterior reversible (EPR) es una entidad clinicorradiologica caracterizada tipicamente por cuadros de cefalea, alteraciones visuales y crisis epilepticas, asociada a edema vasogeno corticosubcortical reversible en la neuroimagen. Objetivo. Presentar una revision de los aspectos fisiopatologicos de esta entidad y tambien de las asociaciones de la EPR descritas en la bibliografia. Desarrollo. Existe una serie de factores desencadenantes bien conocidos, como las crisis hipertensivas, la eclampsia o ciertos medicamentos. La descripcion de cada vez mas casos atipicos desde un punto de vista clinico y radiologico, asi como de posibles nuevos factores desencadenantes, obliga a una redefinicion de la entidad. Conclusiones. La EPR es un conjunto de manifestaciones clinicas y radiologicas que no se pueden enmarcar dentro la palabra 'sindrome'. Aunque la EPR se ha comunicado como irreversible en ciertos casos, el concepto de reversibilidad debe mantenerse en la definicion de esta entidad, ya que, en la mayor parte de los casos, el rapido control de la condicion desencadenante de la EPR permite la reversibilidad de las lesiones.

  4. Dynamic properties of the posterior cricoarytenoid muscle.

    PubMed

    Cooper, D S; Shindo, M; Sinha, U; Hast, M H; Rice, D H

    1994-12-01

    The aim of this research was to investigate the contractile properties of the posterior cricoarytenoid (PCA) muscle. Simultaneous measurements were made of the isometric force, temperature, and electromyographic activity of the dorsal cricoarytenoid muscle of anesthetized dogs during supramaximal stimulation of the recurrent laryngeal nerve for twitch and tetanic contraction. The conduction delay between stimulation of the recurrent nerve at the level of the larynx and the onset of the muscle action potential averaged 2.0 +/- 0.2 milliseconds (ms), and the latent period between the onset of electrical activity of the muscle and the onset of contraction had a mean duration of 3.3 +/- 0.8 ms. The mean of isometric contraction times found was 33.3 +/- 2.0 ms, shorter than most previous studies of canine PCA muscle. Tetanic frequency defined as smooth contraction was higher than previous estimates. Considerations of scaling of physiological time based on animal mass were applied to analysis of the experimental findings to make possible systematic comparison of previous findings across species and animal size.

  5. Ganglion cysts of the posterior cruciate ligament.

    PubMed

    Shetty, Gautam M; Nha, Kyung Wook; Patil, Sachin P; Chae, Dong Ju; Kang, Ki Hoon; Yoon, Jung Ro; Choo, Suk Kyu; Yi, Jeong Woo; Kim, Ji Hoon; Baek, Jong Ryoon

    2008-08-01

    Ganglion cysts of the posterior cruciate ligament (PCL) are uncommon lesions found incidentally on MRI and arthroscopy. Twenty patients (11 males and nine females) with the mean age of 35 years presenting with a variety of knee signs and symptoms were found to have PCL cysts on MRI. Out of these, thirteen patients (65%) had isolated symptomatic PCL cysts and seven patients had associated chondral and meniscal lesions. Eight out of the 20 patients (40%) gave a history of antecedent trauma. On arthroscopy, the majority of the cysts were situated at the midsubstance of the ligament with inter-cruciate distension and no involvement of the substance of the ligament. The content of the cysts varied with the majority having yellowish viscous fluid and three containing serous and bloody fluid. All cysts were successfully treated arthroscopically through standard anterior, posteromedial and posterolateral portals with no signs of recurrence on MRI at a mean followup of 24 months. PCL cysts may clinically mimic meniscal or chondral lesions and preoperatively, MRI is essential for the diagnosis of ganglion cysts arising from the PCL. Ganglion cysts of the PCL can be successfully treated arthroscopically using standard portals.

  6. Posterior Probability Matching and Human Perceptual Decision Making.

    PubMed

    Murray, Richard F; Patel, Khushbu; Yee, Alan

    2015-06-01

    Probability matching is a classic theory of decision making that was first developed in models of cognition. Posterior probability matching, a variant in which observers match their response probabilities to the posterior probability of each response being correct, is being used increasingly often in models of perception. However, little is known about whether posterior probability matching is consistent with the vast literature on vision and hearing that has developed within signal detection theory. Here we test posterior probability matching models using two tools from detection theory. First, we examine the models' performance in a two-pass experiment, where each block of trials is presented twice, and we measure the proportion of times that the model gives the same response twice to repeated stimuli. We show that at low performance levels, posterior probability matching models give highly inconsistent responses across repeated presentations of identical trials. We find that practised human observers are more consistent across repeated trials than these models predict, and we find some evidence that less practised observers more consistent as well. Second, we compare the performance of posterior probability matching models on a discrimination task to the performance of a theoretical ideal observer that achieves the best possible performance. We find that posterior probability matching is very inefficient at low-to-moderate performance levels, and that human observers can be more efficient than is ever possible according to posterior probability matching models. These findings support classic signal detection models, and rule out a broad class of posterior probability matching models for expert performance on perceptual tasks that range in complexity from contrast discrimination to symmetry detection. However, our findings leave open the possibility that inexperienced observers may show posterior probability matching behaviour, and our methods provide new tools

  7. Mitral Valve Mechanics Following Posterior Leaflet Patch Augmentation

    PubMed Central

    Rahmani, Azadeh; Rasmussen, Ann Q.; Honge, Jesper L.; Ostli, Bjorn; Levine, Robert A.; Hagège, Albert; Nygaard, Hans; Nielsen, Sten L.; Jensen, Morten O.

    2013-01-01

    Background and aim of the study Attention towards the optimization of mitral valve repair methods is increasing. Patch augmentation is one strategy used to treat functional ischemic mitral regurgitation (FIMR). The study aim was to investigate the force balance changes in specific chordae tendineae emanating from the posterior papillary muscle in a FIMR-simulated valve, following posterior leaflet patch augmentation. Methods Mitral valves were obtained from 12 pigs (body weight 80 kg). An in vitro test set-up simulating the left ventricle was used to hold the valves. The left ventricular pressure was regulated with water to simulate different static pressures during valve closure. A standardized oval pericardial patch (17 × 29 mm) was introduced into the posterior leaflet from mid P2 to the end of the P3 scallop. Dedicated miniature transducers were used to record the forces exerted on the chordae tendineae. Data were acquired before and after 12 mm posterior and 5 mm apical posterior papillary muscle displacement to simulate the effect from one of the main contributors of FIMR, before and after patch augmentation. Results The effect of displacing the posterior papillary muscle induced tethering on the intermediate chordae tendineae to the posterior leaflet, and resulted in a 39.8% force increase (p = 0.014). Posterior leaflet patch augmentation of the FIMR valve induced a 31.1% force decrease (p = 0.007). There was no difference in force between the healthy and the repaired valve simulations (p = 0.773). Conclusion Posterior leaflet patch augmentation significantly reduced the forces exerted on the intermediate chordae tendineae from the posterior papillary muscle following FIMR simulation. As changes in chordal tension lead to a redistribution of the total stress exerted on the valve, patch augmentation may have an adverse long-term influence on mitral valve function and remodeling. PMID:23610985

  8. Posterior Probability Matching and Human Perceptual Decision Making

    PubMed Central

    Murray, Richard F.; Patel, Khushbu; Yee, Alan

    2015-01-01

    Probability matching is a classic theory of decision making that was first developed in models of cognition. Posterior probability matching, a variant in which observers match their response probabilities to the posterior probability of each response being correct, is being used increasingly often in models of perception. However, little is known about whether posterior probability matching is consistent with the vast literature on vision and hearing that has developed within signal detection theory. Here we test posterior probability matching models using two tools from detection theory. First, we examine the models’ performance in a two-pass experiment, where each block of trials is presented twice, and we measure the proportion of times that the model gives the same response twice to repeated stimuli. We show that at low performance levels, posterior probability matching models give highly inconsistent responses across repeated presentations of identical trials. We find that practised human observers are more consistent across repeated trials than these models predict, and we find some evidence that less practised observers more consistent as well. Second, we compare the performance of posterior probability matching models on a discrimination task to the performance of a theoretical ideal observer that achieves the best possible performance. We find that posterior probability matching is very inefficient at low-to-moderate performance levels, and that human observers can be more efficient than is ever possible according to posterior probability matching models. These findings support classic signal detection models, and rule out a broad class of posterior probability matching models for expert performance on perceptual tasks that range in complexity from contrast discrimination to symmetry detection. However, our findings leave open the possibility that inexperienced observers may show posterior probability matching behaviour, and our methods provide new tools

  9. Evidence for magma recharge and cumulate assimilation within the Fossa delle Felci (Salina Island, Italy) volcanic sequence

    NASA Astrophysics Data System (ADS)

    Mayfield, A. M.; Bohrson, W. A.; Hunt, R.; Creamer, J. B.

    2011-12-01

    Integrating plagioclase in situ chemical and textural analyses with MELTS (Ghiorso & Sack 1995) provides quantitative information about magma chamber processes such as recharge (R), assimilation (A) and fractional crystallization (FC) and constrains variables such as pressure, temperature and water content. Studies on Salina Island have documented volcanic sequences ranging from basalt to rhyolite that erupted between ~500-13 ka (Gertisser & Keller 2000). In the Fossa delle Felci sequence, basalts to basaltic andesites (herein called basalt) are the lowest units in the series followed upsection by dacite, andesite and basaltic andesite. Thirteen samples were chosen for whole rock major and trace element and Sr isotope analysis with a subset of six representative samples chosen for in situ textural and chemical analysis. The basalt shows the least complex plagioclase textures, as documented by Nomarski Differential Interference Contrast imaging. Textural complexity increases with increasing whole rock SiO2. No overlap occurs in core and rim anorthite (An mol%) values for the basalt, with varying degrees of overlap in core and rim An values for the remaining samples. The An range for all crystals is 93-39. Whole rock major and trace elements show systematic trends suggesting differentiation controlled by FC. The basalt displays anomalously high Al2O3, CaO and low MgO. For most samples, whole rock Sr behaves compatibly, but two andesites have anomalously high [Sr]. Overall, in situ plagioclase [Sr] range from 918-2312 ppm with the lowest values in the basalt and the highest in the dacite. Whole rock 87Sr/86Sr range from 0.70475-0.70433. Basaltic andesites are the least radiogenic, and andesites are the most radiogenic; thus, there are no simple correlations with indices of differentiation. Preliminary in situ LA-ICPMS analyses of one andesite yield 87Sr/86Sr of 0.70439-0.70408 with values decreasing rimward; all in situ values are lower than the whole rock value

  10. Posterior urethral valves: long-term outcome.

    PubMed

    Caione, Paolo; Nappo, Simona Gerocarni

    2011-10-01

    Posterior urethral valves represent the most common cause of bladder outlet obstruction in infancy that impairs renal and bladder function. Long-term outcome of patients with previous PUV is evaluated. Patients over 18 years of age, treated from 1982 to 1995 before the age of 3 years were considered. Previous surgery, renal function, bladder activity, urinary incontinence, and fertility/sexual activity were evaluated. Clinical interview, creatinine clearance, uroflowmetry with ultrasound post-void urine residue, and self-administered questionnaire were recorded. Out of 45 identified records, 24 patients (53.3%) accepted to be enrolled (age 18-34 years, mean 23 years). The mean follow-up was 19.5 years (16-30 years). Out of the 21 excluded patients, 20 did not reply to the clinical interview and 1 died at age of 6 years. All the 24 patients had early endoscopic section of PUV; nine also received transient ureterocutaneostomy or vesicostomy. Ureteroneocystostomy was performed in five patients and ureterocystoplasty with unilateral nephrectomy in two. At follow-up chronic renal failure was detected in 13 patients (54.1%) and 9 (37.5%) had arterial hypertension. End-stage renal disease developed in five patients (20.8%): three had successful renal transplantation and two were in dialysis. Lower urinary tract symptoms were present in seven patients (29.1%). No significant fertility deficit and sexual dysfunction were observed in 23 patients, while 1 patient was azoospermic. No paternity was reported so far. Long-term outcome of patients with previously treated PUV is mandatory. Kidney, bladder, and sexual functions should be monitored till adulthood to verify any modified behaviour.

  11. The language profile of Posterior Cortical Atrophy

    PubMed Central

    Crutch, Sebastian J.; Lehmann, Manja; Warren, Jason D.; Rohrer, Jonathan D.

    2015-01-01

    Background Posterior Cortical Atrophy (PCA) is typically considered to be a visual syndrome, primarily characterised by progressive impairment of visuoperceptual and visuospatial skills. However patients commonly describe early difficulties with word retrieval. This paper details the first systematic analysis of linguistic function in PCA. Characterising and quantifying the aphasia associated with PCA is important for clarifying diagnostic and selection criteria for clinical and research studies. Methods Fifteen patients with PCA, 7 patients with logopenic/phonological aphasia (LPA) and 18 age-matched healthy participants completed a detailed battery of linguistic tests evaluating auditory input processing, repetition and working memory, lexical and grammatical comprehension, single word retrieval and fluency, and spontaneous speech. Results Relative to healthy controls, PCA patients exhibited language impairments across all the domains examined, but with anomia, reduced phonemic fluency and slowed speech rate the most prominent deficits. PCA performance most closely resembled that of LPA patients on tests of auditory input processing, repetition and digit span, but was relatively stronger on tasks of comprehension and spontaneous speech. Conclusions The study demonstrates that in addition to the well-reported degradation of vision, literacy and numeracy, PCA is characterised by a progressive oral language dysfunction with prominent word retrieval difficulties. Overlap in the linguistic profiles of PCA and LPA, which are both most commonly caused by Alzheimer’s disease, further emphasises the notion of a phenotypic continuum between typical and atypical manifestations of the disease. Clarifying the boundaries between AD phenotypes has important implications for diagnosis, clinical trial recruitment and investigations into biological factors driving phenotypic heterogeneity in AD. Rehabilitation strategies to ameliorate the phonological deficit in PCA are required

  12. Outcome on hearing and facial nerve function in microsurgical treatment of small vestibular schwannoma via the middle cranial fossa approach.

    PubMed

    Ginzkey, Christian; Scheich, Matthias; Harnisch, Wilma; Bonn, Verena; Ehrmann-Müller, Desiree; Shehata-Dieler, Wafaa; Mlynski, Robert; Hagen, Rudolf

    2013-03-01

    Encouraging results regarding hearing preservation and facial nerve function as well as increasing understanding of the natural behaviour of vestibular schwannomas have led to the recommendation of an early treatment in small VS. The aim of the present study was to evaluate current data on functional outcome of patients with small VS treated by middle cranial fossa (MCF) approach. A retrospective chart study of all cases treated by MCF approach between October 2007 and September 2011 was performed. Records were analyzed regarding demographical data, tumor size, hearing status, vestibular function and facial nerve function. Facial nerve function was classified according to the House-Brackmann scale (HB). Hearing status was classified according to the American Association of Otolaryngology-Head and Neck Surgery (AAO-HNS) and a modified classification of Gardner and Robertson (GR). Eighty-nine patients were included in the study; 41 % of VS was classified as intracanalicular (stage 1) and 59 % as stage 2. From 65 patients with a preoperative hearing status according to AAO-HNS A or B, 74 % still presented with A or B after surgery. Using a modified GR classification, from 70 patients categorized as class I or II prior to surgery, 70 % were still class I or II. Looking to the facial nerve function 1 week after surgery, 82 % of patients presented with HB 1 or 2. Three to twelve months later, 96 % demonstrated HB 1 or 2. A persisting facial palsy was recorded in four patients. Preoperative hearing status was evaluated as a prognostic factor for postoperative hearing, whereas no influence was detected in ABR, vestibular function and tumor length. Early diagnosis of small VS due to high-sensitive MRI requires the management of this tumor entity. Natural behaviour of VS in many cases demonstrates an increase of tumor size over time with deterioration of hearing status. The presented data underline the recommendation of an early surgical treatment in small VS as a valuable

  13. Posterior ankle impingement syndrome: A systematic four-stage approach

    PubMed Central

    Yasui, Youichi; Hannon, Charles P; Hurley, Eoghan; Kennedy, John G

    2016-01-01

    Posterior ankle impingement syndrome (PAIS) is a common injury in athletes engaging in repetitive plantarflexion, particularly ballet dancers and soccer players. Despite the increase in popularity of the posterior two-portal hindfoot approach, concerns with the technique remain, including; the technical difficulty, relatively steep learning curve, and difficulty performing simultaneous anterior ankle arthroscopy. The purpose of the current literature review is to provide comprehensive knowledge about PAIS, and to describe a systematic four-stage approach of the posterior two-portal arthroscopy. The etiology, clinical presentation, diagnostic strategies are first introduced followed by options in conservative and surgical management. A detailed systematic approach to posterior hindfoot arthroscopy is then described. This technique allows for systematic review of the anatomic structures and treatment of the bony and/or soft tissue lesions in four regions of interest in the hindfoot (superolateral, superomedial, inferomedial, and inferolateral). The review then discusses biological adjuncts and postoperative rehabilitation and ends with a discussion on the most recent clinical outcomes after posterior hindfoot arthroscopy for PAIS. Although clinical evidence suggests high success rates following posterior hindfoot arthroscopy in the short- and mid-term it may be limited in the pathology that can be addressed due to the technical skills required, but the systematic four-stage approach of the posterior two-portal arthroscopy may improve upon this problem. PMID:27795947

  14. Neural correlates of cognitive impairment in posterior cortical atrophy.

    PubMed

    Kas, Aurélie; de Souza, Leonardo Cruz; Samri, Dalila; Bartolomeo, Paolo; Lacomblez, Lucette; Kalafat, Michel; Migliaccio, Raffaella; Thiebaut de Schotten, Michel; Cohen, Laurent; Dubois, Bruno; Habert, Marie-Odile; Sarazin, Marie

    2011-05-01

    With the prospect of disease-modifying drugs that will target the physiopathological process of Alzheimer's disease, it is now crucial to increase the understanding of the atypical focal presentations of Alzheimer's disease, such as posterior cortical atrophy. This study aimed to (i) characterize the brain perfusion profile in posterior cortical atrophy using regions of interest and a voxel-based approach; (ii) study the influence of the disease duration on the clinical and imaging profiles; and (iii) explore the correlations between brain perfusion and cognitive deficits. Thirty-nine patients with posterior cortical atrophy underwent a specific battery of neuropsychological tests, mainly targeting visuospatial functions, and a brain perfusion scintigraphy with 99mTc-ethyl cysteinate dimer. The imaging analysis included a comparison with a group of 24 patients with Alzheimer's disease, matched for age, disease duration and Mini-Mental State Examination, and 24 healthy controls. The single-photon emission computed tomography profile in patients with posterior cortical atrophy was characterized by extensive and severe hypoperfusion in the occipital, parietal, posterior temporal cortices and in a smaller cortical area corresponding to the frontal eye fields (Brodmann areas 6/8). Compared with patients with Alzheimer's disease, the group with posterior cortical atrophy showed more severe occipitoparietal hypoperfusion and higher perfusion in the frontal, anterior cingulate and mesiotemporal regions. When considering the disease duration, the functional changes began and remained centred on the posterior lobes, even in the late stage. Correlation analyses of brain perfusion and neuropsychological scores in posterior cortical atrophy highlighted the prominent role of left inferior parietal damage in acalculia, Gerstmann's syndrome, left-right indistinction and limb apraxia, whereas damage to the bilateral dorsal occipitoparietal regions appeared to be involved in B

  15. Detection of Neisseria gonorrhoeae Isolates from Tonsils and Posterior Oropharynx

    PubMed Central

    Whiley, D. M.; Lee, D. M.; Snow, A. F.; Fairley, C. K.; Peel, J.; Bradshaw, C. S.; Hocking, J. S.; Lahra, M. M.; Chen, M. Y.

    2015-01-01

    We examined the factors influencing gonorrhea detection at the pharynx. One hundred men infected with Neisseria gonorrhoeae were swabbed from the tonsils and posterior oropharynx. N. gonorrhoeae was reisolated from the tonsils and posterior oropharynx in 62% and 52%, respectively (P = 0.041). Culture positivity was greater with higher gonococcal DNA loads at the tonsils (P = 0.001) and oropharynx (P < 0.001). N. gonorrhoeae can be cultured from the tonsils and posterior oropharynx with greater isolation rates where gonococcal loads are higher. PMID:26292303

  16. Immunopathology of the noninfectious posterior and intermediate uveitides.

    PubMed

    Boyd, S R; Young, S; Lightman, S

    2001-01-01

    The posterior and intermediate uveitides share an underlying immune etiology; however, they can be clinically and immunopathologically distinguished. Although the initiating stimuli for posterior and intermediate uveities are not known, it is believed that an exogenous agent (such as a bacterium or a virus) or an endogenous molecule may induce disease. In either case, T-helper lymphocytes in conjunction with human leukocyte antigens are likely to be involved. This review examines the epidemiology, histology, immunopathology, and theories of pathogenesis of several posterior and intermediate uveitides, including sympathetic ophthalmia, Vogt-Koyanagi-Harada syndrome, Behçet's disease, sarcoidosis, intermediate uveitis, white dot syndromes, and birdshot retinochoroidopathy.

  17. Posterior cortical atrophy: an atypical variant of Alzheimer disease.

    PubMed

    Suárez-González, Aida; Henley, Susie M; Walton, Jill; Crutch, Sebastian J

    2015-06-01

    Posterior cortical atrophy (PCA) is a neurodegenerative syndrome characterized by striking progressive visual impairment and a pattern of atrophy mainly involving posterior cortices. PCA is the most frequent atypical presentation of Alzheimer disease. The purpose of this article is to provide a summary of PCA's neuropsychiatric manifestations. Emotional and psychotic symptoms are discussed in the context of signal characteristic features of the PCA syndrome (the early onset, focal loss of visual perception, focal posterior brain atrophy) and the underlying cause of the disease. The authors' experience with psychotherapeutic intervention and PCA support groups is shared in detail.

  18. Incidence and surgical importance of the posterior gastric artery.

    PubMed Central

    Suzuki, K; Prates, J C; DiDio, L J

    1978-01-01

    In a series of 61 adult cadavers, the posterior gastric artery was found in 38 (62.3%), originating from the superior aspect of the mid-third of the splenic artery. The posterior gastric artery, running behind the parietal peritoneum of the omental bursa, produced a peritoneal fold before reaching the posterior wall of the superior portion of the gastric body, near the cardiac region, and the fundus. Its high incidence, hidden origin, deep course, and distribution make this artery very important for surgical procedures relating to the stomach, pancreas, spleen, and celiac region. It may be crucial, especially if partial gastric resection of splenectomy have obliterated other gastric vessels. PMID:629615

  19. Ossification of the posterior longitudinal ligament: a case report

    PubMed Central

    Aker, PD; O’Connor, SM; Mior, SA; Beauchemin, D

    1989-01-01

    Ossification of the posterior longitudinal ligament (OPLL) has recently been recognized as a clinical entity. It is a rare condition, having a higher incidence in the Japanese population. It is characterized by hyperplasia of cartilage cells with eventual endochondral ossification of the posterior longitudinal ligament. The radiographic signs are characteristic and consist of a linear band of ossified tissue along the posterior margin of the vertebral body. OPLL can be associated with mild to serious neurological complications due to spinal cord or nerve root compression, or it may be asymptomatic. This paper reviews the radiological, clinical and therapeutic aspects of this rare condition. ImagesFigures 1 and 2Figures 3 and 4

  20. Posterior Wall Blowout in Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Mitchell, Justin J.; Dean, Chase S.; Chahla, Jorge; Menge, Travis J.; Cram, Tyler R.; LaPrade, Robert F.

    2016-01-01

    Violation of the posterior femoral cortex, commonly referred to as posterior wall blowout, can be a devastating intraoperative complication in anterior cruciate ligament (ACL) reconstruction and lead to loss of graft fixation or early graft failure. If cortical blowout occurs despite careful planning and adherence to proper surgical technique, a thorough knowledge of the anatomy and alternative fixation techniques is imperative to ensure optimal patient outcomes. This article highlights anatomic considerations for femoral tunnel placement in ACL reconstruction and techniques for avoidance and salvage of a posterior wall blowout. PMID:27335885

  1. Imaging of the pediatric thymus: Clinicoradiologic approach

    PubMed Central

    Manchanda, Smita; Bhalla, Ashu S; Jana, Manisha; Gupta, Arun K

    2017-01-01

    The thymus is a lymphatic organ that undergoes dynamic changes with age and disease. It is important to be familiar with these physiological changes in the thymus gland to be able to identify pathology and make an accurate diagnosis. The thymus may be involved in multisystem disorders or show focal isolated lesions. The aim of this article is to review the radiological anatomy of the thymus, normal variants, and pathology including hyperplasia and benign/malignant lesions involving the thymus gland in the pediatric age group. We also propose an algorithmic approach for imaging evaluation of a suspected thymic mass on the basis of morphologic features. PMID:28224091

  2. Acute Necrotizing Encephalopathy: An Underrecognized Clinicoradiologic Disorder

    PubMed Central

    Wu, Xiujuan; Wu, Wei; Pan, Wei; Wu, Limin; Liu, Kangding; Zhang, Hong-Liang

    2015-01-01

    Acute necrotizing encephalopathy (ANE) is a rare but distinctive type of acute encephalopathy with global distribution. Occurrence of ANE is usually preceded by a virus-associated febrile illness and ensued by rapid deterioration. However, the causal relationship between viral infections and ANE and the exact pathogenesis of ANE remain unclear; both environmental and host factors might be involved. Most cases of ANE are sporadic and nonrecurrent, namely, isolated or sporadic ANE; however, few cases are recurrent and with familial episodes. The recurrent and familial forms of ANE were found to be incompletely autosomal-dominant. Further the missense mutations in the gene encoding the nuclear pore protein Ran Binding Protein 2 (RANBP2) were identified. Although the clinical course and the prognosis of ANE are diverse, the hallmark of neuroradiologic manifestation of ANE is multifocal symmetric brain lesions which are demonstrated by computed tomography (CT) or magnetic resonance imaging (MRI). The treatment of ANE is still under investigation. We summarize the up-to-date knowledge on ANE, with emphasis on prompt diagnosis and better treatment of this rare but fatal disease. PMID:25873770

  3. Reversible dyscognition in patients with a unilateral, middle fossa arachnoid cyst revealed by using a laptop based neuropsychological test battery (CANTAB).

    PubMed

    Torgersen, Johan; Helland, Christian; Flaatten, Hans; Wester, Knut

    2010-11-01

    The aim of this study was to evaluate and validate the Cambridge Neuropsychological Test Automated Battery (CANTAB) in a Norwegian group of patients undergoing surgery for middle fossa arachnoid cysts (AC). We also wanted to assess health related quality of life (HRQOL) in these patients to see if it could be improved by decompression of the AC. Adult patients (>18 years) with unilateral middle fossa AC and no previous history of neurological disease, head injury, or a psychiatric disorder were eligible for inclusion. We used four tests from CANTAB to assess the level of neuropsychological performance: paired associate learning (PAL) and delayed matching to sample (DMS) assessed temporal lobe functions, while Stockings of Cambridge (SOC) and intra-extra dimensional (IED) shift focused on frontal lobe functions. Patients with postoperative cerebral complications were reported, but excluded from neuropsychological follow-up. In addition to the CANTAB data, pre- and postoperative clinical and radiological data were collected. HRQOL was assessed using Short Form 36 (SF-36) pre- and postoperatively. We found significant improvement in the two temporal tests assessing memory, but no improvement in the two frontal tests assessing executive function. HRQOL was significantly reduced preoperatively in two of eight SF-36 domains and improved significantly in four domains postoperatively. CANTAB facilitates detection of cognitive improvements after decompression of the cyst in patients with AC in the middle fossa. The improvements were detected on the tests sensitive to temporal lobe problems only, not on the tests more sensitive to frontal lobe affection. This establishes construct validity for CANTAB for the first time in this population.

  4. Evaluation of temporomandibular fossa and mandibular condyle in adolescent patients affected by bilateral cleft lip and palate using cone beam computed tomography.

    PubMed

    Uçar, Faruk Izzet; Buyuk, Suleyman Kutalmış; Şekerci, Ahmet Ercan; Celikoglu, Mevlut

    2016-11-01

    The purposes of this study were to investigate the position of the mandibular condyle and temporomandibular fossa between the adolescent patients affected by bilateral cleft lip and palate (BCLP) and well-matched controls without any cleft by using cone-beam computed tomography (CBCT). The study sample consisted of 17 patients (7 females and 10 males; mean age, 14.27 ± 2.83 years) affected by BCLP and 17 patients (6 females and 11 males; mean age, 14.27 ± 2.12 years) as age-and sex-matched control group without any cleft. Using cone-beam computed tomography segmented three-dimensional temporomandibular fossa and mandibular condyle images were reconstructed and angular, linear, and volumetric measurements of the patients in both sides of the groups were examined using Paired and Student's t-tests. Comparison of the sides showed that both sides were found to be similar in BCLP and control groups, except the condylar angulation of the right side was found to be higher compared to that of the left side in both groups (p < 0.05). Comparison of the groups showed that the patients affected by BCLP and non-cleft patients had similar values for all parameters, except for the condylar angulation in the right side (BCLP group had less angulation compared to controls; p < 0.05). The condylar volume was found to be slightly less in the BCLP group in both sides compared to the controls (p > 0.05). The positions of the mandibular condyle and temporomandibular fossa were found to be similar in patients affected by BCLP and control group of without any cleft. SCANNING 38:720-726, 2016. © 2016 Wiley Periodicals, Inc.

  5. Modified posterior vertebral column resection for Kümmell disease

    PubMed Central

    Liu, Feng-Yu; Huo, Li-Shuang; Liu, Sen; Wang, Hui; Zhang, Li-Jun; Yang, Da-Long; Ding, Wen-Yuan

    2017-01-01

    Abstract Rationale: Kümmell's disease is defined as delayed traumatic vertebral collapse disease in which patients develop a kyphosis after asymptomatic minor spinal trauma. Both anterior approach and posterior approach have been reported, however, there is no standard treatment for Kümmell's disease. Patient concerns: We described a successful modified posterior vertebral column resection in a patient with Kümmell's disease. A 65-year-old woman reported persistent back pain for almost three months. Diagnoses: Kümmell's disease was diagnosed based on computer tomography (CT) and magnetic resonance imaging (MRI). Interventions: Modified posterior vertebral column resection combined with short-segment fixation was designed to treat this disease. Outcomes: The procedure was successful without any complications. Patient reported that symptoms were obviously improved in one week after operation. Lessons: Modified posterior vertebral column resection combined with short-segment fixation is an effective treatment option for Kümmell's disease. PMID:28151882

  6. Aneurysms of the posterior cerebral artery in children.

    PubMed

    Romero, F J; Tàpies, C; Ibarra, B; Rovira, M

    1988-01-01

    Two cases of aneurysms of the posterior cerebral artery, diagnosed by CT and confirmed angiographically, are reported. In the first case, the aneurysm was discovered fortuitously. The second began with intracerebral haemorrhage. A review of the literature is reported.

  7. Resection of Beak-Type Thoracic Ossification of the Posterior Longitudinal Ligament from a Posterior Approach under Intraoperative Neurophysiological Monitoring for Paralysis after Posterior Decompression and Fusion Surgery.

    PubMed

    Imagama, Shiro; Ando, Kei; Ito, Zenya; Kobayashi, Kazuyoshi; Hida, Tetsuro; Ito, Kenyu; Ishikawa, Yoshimoto; Tsushima, Mikito; Matsumoto, Akiyuki; Tanaka, Satoshi; Morozumi, Masayoshi; Machino, Masaaki; Ota, Kyotaro; Nakashima, Hiroaki; Wakao, Norimitsu; Nishida, Yoshihiro; Matsuyama, Yukihiro; Ishiguro, Naoki

    2016-12-01

    Study Design Prospective clinical study. Objective Posterior decompression and fusion surgery for beak-type thoracic ossification of the posterior longitudinal ligament (T-OPLL) generally has a favorable outcome. However, some patients require additional surgery for postoperative severe paralysis, a condition that is inadequately discussed in the literature. The objective of this study was to describe the efficacy of a procedure we refer to as "resection at an anterior site of the spinal cord from a posterior approach" (RASPA) for severely paralyzed patients after posterior decompression and fusion surgery for beak-type T-OPLL. Methods Among 58 consecutive patients who underwent posterior decompression and fusion surgery for beak-type T-OPLL since 1999, 3 with postoperative paralysis (5%) underwent RASPA in our institute. Clinical records, the Japanese Orthopaedic Association score, gait status, intraoperative neurophysiological monitoring (IONM) findings, and complications were evaluated in these cases. Results All three patients experienced a postoperative decline in Manual Muscle Test (MMT) scores of 0 to 2 after the first surgery. RASPA was performed 3 weeks after the first surgery. All patients showed gradual improvements in MMT scores for the lower extremity and in ambulatory status; all could walk with a cane at an average of 4 months following RASPA surgery. There were no postoperative complications. Conclusions RASPA surgery for beak-type T-OPLL after posterior decompression and fusion surgery resulted in good functional outcomes as a salvage surgery for patients with severe paralysis. Advantages of RASPA include a wide working space, no spinal cord retraction, and additional decompression at levels without T-OPLL resection and spinal cord shortening after additional dekyphosis and compression maneuvers. When used with IONM, this procedure may help avoid permanent postoperative paralysis.

  8. Resection of Beak-Type Thoracic Ossification of the Posterior Longitudinal Ligament from a Posterior Approach under Intraoperative Neurophysiological Monitoring for Paralysis after Posterior Decompression and Fusion Surgery

    PubMed Central

    Imagama, Shiro; Ando, Kei; Ito, Zenya; Kobayashi, Kazuyoshi; Hida, Tetsuro; Ito, Kenyu; Ishikawa, Yoshimoto; Tsushima, Mikito; Matsumoto, Akiyuki; Tanaka, Satoshi; Morozumi, Masayoshi; Machino, Masaaki; Ota, Kyotaro; Nakashima, Hiroaki; Wakao, Norimitsu; Nishida, Yoshihiro; Matsuyama, Yukihiro; Ishiguro, Naoki

    2016-01-01

    Study Design Prospective clinical study. Objective Posterior decompression and fusion surgery for beak-type thoracic ossification of the posterior longitudinal ligament (T-OPLL) generally has a favorable outcome. However, some patients require additional surgery for postoperative severe paralysis, a condition that is inadequately discussed in the literature. The objective of this study was to describe the efficacy of a procedure we refer to as “resection at an anterior site of the spinal cord from a posterior approach” (RASPA) for severely paralyzed patients after posterior decompression and fusion surgery for beak-type T-OPLL. Methods Among 58 consecutive patients who underwent posterior decompression and fusion surgery for beak-type T-OPLL since 1999, 3 with postoperative paralysis (5%) underwent RASPA in our institute. Clinical records, the Japanese Orthopaedic Association score, gait status, intraoperative neurophysiological monitoring (IONM) findings, and complications were evaluated in these cases. Results All three patients experienced a postoperative decline in Manual Muscle Test (MMT) scores of 0 to 2 after the first surgery. RASPA was performed 3 weeks after the first surgery. All patients showed gradual improvements in MMT scores for the lower extremity and in ambulatory status; all could walk with a cane at an average of 4 months following RASPA surgery. There were no postoperative complications. Conclusions RASPA surgery for beak-type T-OPLL after posterior decompression and fusion surgery resulted in good functional outcomes as a salvage surgery for patients with severe paralysis. Advantages of RASPA include a wide working space, no spinal cord retraction, and additional decompression at levels without T-OPLL resection and spinal cord shortening after additional dekyphosis and compression maneuvers. When used with IONM, this procedure may help avoid permanent postoperative paralysis. PMID:27853667

  9. Abnormalities of fixation, saccade and pursuit in posterior cortical atrophy.

    PubMed

    Shakespeare, Timothy J; Kaski, Diego; Yong, Keir X X; Paterson, Ross W; Slattery, Catherine F; Ryan, Natalie S; Schott, Jonathan M; Crutch, Sebastian J

    2015-07-01

    The clinico-neuroradiological syndrome posterior cortical atrophy is the cardinal 'visual dementia' and most common atypical Alzheimer's disease phenotype, offering insights into mechanisms underlying clinical heterogeneity, pathological propagation and basic visual phenomena (e.g. visual crowding). Given the extensive attention paid to patients' (higher order) perceptual function, it is surprising that there have been no systematic analyses of basic oculomotor function in this population. Here 20 patients with posterior cortical atrophy, 17 patients with typical Alzheimer's disease and 22 healthy controls completed tests of fixation, saccade (including fixation/target gap and overlap conditions) and smooth pursuit eye movements using an infrared pupil-tracking system. Participants underwent detailed neuropsychological and neurological examinations, with a proportion also undertaking brain imaging and analysis of molecular pathology. In contrast to informal clinical evaluations of oculomotor dysfunction frequency (previous studies: 38%, current clinical examination: 33%), detailed eyetracking investigations revealed eye movement abnormalities in 80% of patients with posterior cortical atrophy (compared to 17% typical Alzheimer's disease, 5% controls). The greatest differences between posterior cortical atrophy and typical Alzheimer's disease were seen in saccadic performance. Patients with posterior cortical atrophy made significantly shorter saccades especially for distant targets. They also exhibited a significant exacerbation of the normal gap/overlap effect, consistent with 'sticky fixation'. Time to reach saccadic targets was significantly associated with parietal and occipital cortical thickness measures. On fixation stability tasks, patients with typical Alzheimer's disease showed more square wave jerks whose frequency was associated with lower cerebellar grey matter volume, while patients with posterior cortical atrophy showed large saccadic intrusions

  10. Abnormalities of fixation, saccade and pursuit in posterior cortical atrophy

    PubMed Central

    Kaski, Diego; Yong, Keir X. X.; Paterson, Ross W.; Slattery, Catherine F.; Ryan, Natalie S.; Schott, Jonathan M.; Crutch, Sebastian J.

    2015-01-01

    The clinico-neuroradiological syndrome posterior cortical atrophy is the cardinal ‘visual dementia’ and most common atypical Alzheimer’s disease phenotype, offering insights into mechanisms underlying clinical heterogeneity, pathological propagation and basic visual phenomena (e.g. visual crowding). Given the extensive attention paid to patients’ (higher order) perceptual function, it is surprising that there have been no systematic analyses of basic oculomotor function in this population. Here 20 patients with posterior cortical atrophy, 17 patients with typical Alzheimer’s disease and 22 healthy controls completed tests of fixation, saccade (including fixation/target gap and overlap conditions) and smooth pursuit eye movements using an infrared pupil-tracking system. Participants underwent detailed neuropsychological and neurological examinations, with a proportion also undertaking brain imaging and analysis of molecular pathology. In contrast to informal clinical evaluations of oculomotor dysfunction frequency (previous studies: 38%, current clinical examination: 33%), detailed eyetracking investigations revealed eye movement abnormalities in 80% of patients with posterior cortical atrophy (compared to 17% typical Alzheimer’s disease, 5% controls). The greatest differences between posterior cortical atrophy and typical Alzheimer’s disease were seen in saccadic performance. Patients with posterior cortical atrophy made significantly shorter saccades especially for distant targets. They also exhibited a significant exacerbation of the normal gap/overlap effect, consistent with ‘sticky fixation’. Time to reach saccadic targets was significantly associated with parietal and occipital cortical thickness measures. On fixation stability tasks, patients with typical Alzheimer’s disease showed more square wave jerks whose frequency was associated with lower cerebellar grey matter volume, while patients with posterior cortical atrophy showed large

  11. The influence of posterior occlusion when restoring anterior teeth.

    PubMed

    Reshad, Mamaly; Jivraj, Sajid

    2008-08-01

    When any type of esthetic restorative procedure is being considered or performed, a comprehensive diagnosis and treatment plan is required. Attention to the diagnostic signs of the loss of posterior support (LPS) and their influence on the anterior dentition will guarantee a more predictable outcome. Historical solutions and their inadequacies are addressed. Patient presentations are utilized to demonstrate contemporary treatment of patients requiring esthetic rehabilitations who are lacking posterior support.

  12. Parascapular mass revealing primary tuberculosis of the posterior arch

    PubMed Central

    Arbault, Anais; Ornetti, Paul; Chevallier, Olivier; Avril, Julien; Pottecher, Pierre

    2016-01-01

    We report the case of a parascapular abscess revealing primary tuberculosis of the posterior arch in a 31-year-old man. Sectional imaging is essential in order to detect the different lesions of this atypical spinal tuberculosis as osteolysis of the posterior arch extendible to vertebral body, osteocondensation, epidural extension which is common in this location, and high specificity of a zygapophysial, costo-vertebral or transverse arthritis. PMID:27709081

  13. [Tuberculosis of the posterior vertebral arch. A case report].

    PubMed

    Nassar, I; Mahi, M; Semlali, S; Kacemi, L; El Quessar, A; Chakir, N; El Hassani, M R; Jiddane, M

    2002-09-01

    Tuberculosis of the spine usually involves the vertebral body and intervertebral disk. Involvement of the posterior arch is rare. We report a case of tuberculosis involving the posterior elements of the T4 and T5 vertebrae in a 38 year old woman. CT is helpful to assess bony structures whereas MRI is ideal to evaluate the neural structures. Clinical, radiographic, and therapeutic considerations regarding tuberculosis of the spine are reviewed.

  14. Posterior polymorphous dystrophy and keratoglobus in a child.

    PubMed

    Patel, Sangita P; Sajnani, Manoj M; Pineda, Roberto

    2011-01-01

    A 13-year-old boy presented with gradually progressive deterioration of vision in both eyes, bilateral photophobia, and regular headaches. Clinical examination, anterior segment findings, and specular microscopy findings were consistent with the diagnosis of posterior polymorphous dystrophy and keratoglobus. To the authors' knowledge, this is the first pediatric case and the second case overall of the simultaneous occurrence of posterior polymorphous dystrophy and keratoglobus.

  15. Imaging in spinal posterior epidural space lesions: A pictorial essay.

    PubMed

    Gala, Foram B; Aswani, Yashant

    2016-01-01

    Spinal epidural space is a real anatomic space located outside the dura mater and within the spinal canal extending from foramen magnum to sacrum. Important contents of this space are epidural fat, spinal nerves, epidural veins and arteries. Due to close proximity of posterior epidural space to spinal cord and spinal nerves, the lesions present with symptoms of radiculopathy and/or myelopathy. In this pictorial essay, detailed anatomy of the posterior epidural space, pathologies affecting it along with imaging pearls to accurately diagnose them are discussed. Various pathologies affecting the posterior epidural space either arising from the space itself or occurring secondary to vertebral/intervertebral disc pathologies. Primary spinal bone tumors affecting the posterior epidural space have been excluded. The etiological spectrum affecting the posterior epidural space ranges from degenerative, infective, neoplastic - benign or malignant to miscellaneous pathologies. MRI is the modality of choice in evaluation of these lesions with CT scan mainly helpful in detecting calcification. Due to its excellent soft tissue contrast, Magnetic Resonance Imaging is extremely useful in assessing the pathologies of posterior epidural space, to know their entire extent, characterize them and along with clinical history and laboratory data, arrive at a specific diagnosis and guide the referring clinician. It is important to diagnose these lesions early so as to prevent permanent neurological complication.

  16. Optimizing tooth form with direct posterior composite restorations

    PubMed Central

    Raghu, Ramya; Srinivasan, Raghu

    2011-01-01

    Advances in material sciences and technology have provided today's clinicians the strategies to transform the mechanistic approach of operative dentistry into a biologic philosophy. In the last three decades, composite resins have gone from being just an esthetically pleasing way of restoring Class III and Class IV cavities to become the universal material for both anterior and posterior situations as they closely mimic the natural esthetics while restoring the form of the human dentition. In order to enhance their success, clinicians have to rethink their protocol instead of applying the same restorative concepts and principles practiced with metallic restorations. Paralleling the evolution of posterior composite resin materials, cavity designs, restorative techniques and armamentarium have also developed rapidly to successfully employ composite resins in Class II situations. Most of the earlier problems with posterior composites such as poor wear resistance, polymerization shrinkage, postoperative sensitivity, predictable bonding to dentin, etc., have been overcome to a major extent. However, the clinically relevant aspect of achieving tight contacts in Class II situations has challenged clinicians the most. This paper reviews the evolution of techniques and recent developments in achieving predictable contacts with posterior composites. A Medline search was performed for articles on “direct posterior composite contacts.” The keywords used were “contacts and contours of posterior composites.” The reference list of each article was manually checked for additional articles of relevance. PMID:22144797

  17. Imaging in spinal posterior epidural space lesions: A pictorial essay

    PubMed Central

    Gala, Foram B; Aswani, Yashant

    2016-01-01

    Spinal epidural space is a real anatomic space located outside the dura mater and within the spinal canal extending from foramen magnum to sacrum. Important contents of this space are epidural fat, spinal nerves, epidural veins and arteries. Due to close proximity of posterior epidural space to spinal cord and spinal nerves, the lesions present with symptoms of radiculopathy and/or myelopathy. In this pictorial essay, detailed anatomy of the posterior epidural space, pathologies affecting it along with imaging pearls to accurately diagnose them are discussed. Various pathologies affecting the posterior epidural space either arising from the space itself or occurring secondary to vertebral/intervertebral disc pathologies. Primary spinal bone tumors affecting the posterior epidural space have been excluded. The etiological spectrum affecting the posterior epidural space ranges from degenerative, infective, neoplastic - benign or malignant to miscellaneous pathologies. MRI is the modality of choice in evaluation of these lesions with CT scan mainly helpful in detecting calcification. Due to its excellent soft tissue contrast, Magnetic Resonance Imaging is extremely useful in assessing the pathologies of posterior epidural space, to know their entire extent, characterize them and along with clinical history and laboratory data, arrive at a specific diagnosis and guide the referring clinician. It is important to diagnose these lesions early so as to prevent permanent neurological complication. PMID:27857455

  18. One step arthroscopically assisted Latarjet and posterior bone-block, for recurrent posterior instability and anterior traumatic dislocation

    PubMed Central

    D’Ambrosi, Riccardo; Perfetti, Carlo; Garavaglia, Guido; Taverna, Ettore

    2015-01-01

    This case presents the challenges of the surgical management for a patient with a history of recurrent posterior shoulder instability and subsequently traumatic anterior dislocation. The patient was already on the waiting list for an arthroscopic posterior stabilization with anchors, when a car accident caused an additional anterior shoulder dislocation. This traumatic anterior dislocation created a bone loss with a glenoid fracture and aggravated the preexisting posterior instability. In order to address both problems, we decided to perform an arthroscopically assisted Latarjet procedure for anterior instability and to stabilize with a bone graft for posterior instability. To our best knowledge, this type of surgical procedure has so far never been reported in the literature. The purpose of this report is to present the surgical technique and to outline the decision making process. PMID:26288539

  19. A coincidental variation of the axillary artery: the brachioradial artery and the aberrant posterior humeral circumflex artery passing under the tendon of the latissimus dorsi muscle

    PubMed Central

    Konarik, Marek; Kachlik, David; Baca, Vaclav

    2014-01-01

    A case of anomalous terminal branching of the axillary artery was encountered and described in a left upper limb of a male cadaver. A series of 214 upper limbs of Caucasian race was dissected. A variant artery, stemming from the very end of the axillary artery followed a superficial course distally. It passed the cubital fossa, ran on the lateral side of the forearm as usual radial artery, crossed ventrally to the palm and terminated in the deep palmar arch. This vessel is a case of the brachioradial artery (incorrectly termed as the “radial artery with high origin”). Moreover, it was associated with another variation, concerning the aberrant posterior humeral circumflex artery passing under the tendon of the latissimus dorsi muscle. The anatomical knowledge of the axillary region is essential for radiodiagnostic, surgical and traumatologic procedures. The superficially located artery brings an elevated danger of heavy bleeding in all unexpected situations, its variant branching can cause problems in radial catheterization procedures and the anomalously coursing other arterial variant poses an elevated danger in surgical procedures concerning the surgical neck of humerus. PMID:25428677

  20. A coincidental variation of the axillary artery: the brachioradial artery and the aberrant posterior humeral circumflex artery passing under the tendon of the latissimus dorsi muscle.

    PubMed

    Konarik, Marek; Kachlik, David; Baca, Vaclav

    2014-09-11

    A case of anomalous terminal branching of the axillary artery was encountered and described in a left upper limb of a male cadaver. A series of 214 upper limbs of Caucasian race was dissected. A variant artery, stemming from the very end of the axillary artery followed a superficial course distally. It passed the cubital fossa, ran on the lateral side of the forearm as usual radial artery, crossed ventrally to the palm and terminated in the deep palmar arch. This vessel is a case of the brachioradial artery (incorrectly termed as the "radial artery with high origin"). Moreover, it was associated with another variation, concerning the aberrant posterior humeral circumflex artery passing under the tendon of the latissimus dorsi muscle. The anatomical knowledge of the axillary region is essential for radiodiagnostic, surgical and traumatologic procedures. The superficially located artery brings an elevated danger of heavy bleeding in all unexpected situations, its variant branching can cause problems in radial catheterization procedures and the anomalously coursing other arterial variant poses an elevated danger in surgical procedures concerning the surgical neck of humerus.

  1. Preserving Posterior Complex Can Prevent Adjacent Segment Disease following Posterior Lumbar Interbody Fusion Surgeries: A Finite Element Analysis

    PubMed Central

    Huang, Yun-Peng; Du, Cheng-Fei; Cheng, Cheng-Kung; Zhong, Zheng-Cheng; Chen, Xuan-Wei; Wu, Gui; Li, Zhe-Cheng; Ye, Jin-Duo; Lin, Jian-Hua; Wang, Li Zhen

    2016-01-01

    Objective To investigate the biomechanical effects of the lumbar posterior complex on the adjacent segments after posterior lumbar interbody fusion (PLIF) surgeries. Methods A finite element model of the L1–S1 segment was modified to simulate PLIF with total laminectomy (PLIF-LAM) and PLIF with hemilaminectomy (PLIF-HEMI) procedures. The models were subjected to a 400N follower load with a 7.5-N.m moment of flexion, extension, torsion, and lateral bending. The range of motion (ROM), intradiscal pressure (IDP), and ligament force were compared. Results In Flexion, the ROM, IDP and ligament force of posterior longitudinal ligament, intertransverse ligament, and capsular ligament remarkably increased at the proximal adjacent segment in the PLIF-LAM model, and slightly increased in the PLIF-HEMI model. There was almost no difference for the ROM, IDP and ligament force at L5-S1 level between the two PLIF models although the ligament forces of ligamenta flava remarkably increased compared with the intact lumbar spine (INT) model. For the other loading conditions, these two models almost showed no difference in ROM, IDP and ligament force on the adjacent discs. Conclusions Preserved posterior complex acts as the posterior tension band during PLIF surgery and results in less ROM, IDP and ligament forces on the proximal adjacent segment in flexion. Preserving the posterior complex during decompression can be effective on preventing adjacent segment degeneration (ASD) following PLIF surgeries. PMID:27870867

  2. Posterolateral versus posterior interbody fusion in isthmic spondylolisthesis.

    PubMed

    Farrokhi, Majid Reza; Rahmanian, Abdolkarim; Masoudi, Mohammad Sadegh

    2012-05-20

    Spondylolisthesis is a heterogeneous disorder characterized by subluxation of a vertebral body over another in the sagittal plane. Its most common form is isthmic spondylolisthesis (IS). This study aims to compare clinical outcomes of posterolateral fusion (PLF) with posterior lumbar interbody fusion (PLIF) with posterior instrumentation in the treatment of IS. We performed a randomized prospective study in which 80 patients out of a total of 85 patients with IS were randomly allocated to one of two groups: PLF with posterior instrumentation (group I) or PLIF with posterior instrumentation (group II). Posterior decompression was performed in the patients. The Oswestry low back pain disability (OLBP) scale and Visual Analogue Scale (VAS) were used to evaluate the quality of life (QoL) and pain, respectively. Fisher's exact test was used to evaluate fusion rate and the Mann-Whitney U test was used to compare categorical data. Fusion in group II was significantly better than in group I (p=0.012). Improvement in low back pain was statistically more significant in group I (p=0.001). The incidence of neurogenic claudication was significantly lower in group I than in group II (p=0.004). In group I, there was no significant correlation between slip Meyerding grade and disc space height, radicular pain, and low back pain. There was no significant difference in post-operative complications at 1-year follow-up. Our data showed that PLF with posterior instrumentation provides better clinical outcomes and more improvement in low back pain compared to PLIF with posterior instrumentation despite the low fusion rate.

  3. Interoceptive awareness changes the posterior insula functional connectivity profile.

    PubMed

    Kuehn, Esther; Mueller, Karsten; Lohmann, Gabriele; Schuetz-Bosbach, Simone

    2016-04-01

    Interoceptive awareness describes the ability to consciously perceive inner bodily signals, such as one's own heartbeat. The right anterior insula is assumed to mediate this ability. The role of the posterior insula, particularly posterior-to-anterior insula signal flows is less clear in this respect. We scanned 27 healthy people with either high or low interoceptive awareness using 3T fMRI, while they either monitored their own heartbeats, or external tones, respectively. We used a combination of network centrality and bivariate connectivity analyses to characterize changes in cortical signal flows between the posterior insula and the anterior insula during interoceptive awareness or exteroceptive awareness, respectively. We show that heartbeat monitoring was accompanied by reduced network centrality of the right posterior insula, and decreased functional connectivity strengths between the right posterior insula and the right mid and anterior insula. In addition, decreased signal flows between the right posterior insula and the bilateral anterior cingulate cortices, and the bilateral orbitofrontal cortices were observed during interoceptive awareness. Functional connectivity changes were only shown by people with high interoceptive awareness, and occurred specifically within the low-frequency range (i.e., <0.1 Hz). Both groups did not differ in their functional connectivity profiles during rest. Our results show for the first time that interoceptive awareness changes intra-insula signal flows in the low-frequency range. We speculate that the selective inhibition of slow signal progression along the posterior-to-anterior insula pathway during interoceptive awareness allows the salient and noiseless detection of one's own heartbeat.

  4. Posterior scissors-bite: masticatory jaw movement and muscle activity.

    PubMed

    Tomonari, H; Kubota, T; Yagi, T; Kuninori, T; Kitashima, F; Uehara, S; Miyawaki, S

    2014-04-01

    Scissors-bite is a malocclusion characterised by buccal inclination or buccoversion of the maxillary posterior tooth and/or linguoclination or linguoversion of the mandibular posterior tooth. This type of malocclusion causes reduced contact of the occlusal surfaces and can cause excessive vertical overlapping of the posterior teeth. This case-control study is the first to evaluate both masticatory jaw movement and masseter and temporalis muscle activity in patients with unilateral posterior scissors-bite. Jaw movement variables and surface electromyography data were recorded in 30 adult patients with unilateral posterior scissors-bite malocclusion and 18 subjects with normal occlusion in a case-control study. The chewing pattern on the scissors-bite side significantly differed from that of the non-scissors-bite side in the patients and of the right side in the normal subjects. These differences included a narrower chewing pattern (closing angle, P < 0.01; cycle width, P < 0.01), a longer closing duration (P < 0.05), a slower closing velocity (P < 0.01) and lower activities of both the temporalis (P < 0.05) and the masseter (P < 0.05) muscles on the working side. In 96% of the patients with unilateral posterior scissors-bite, the preferred chewing side was the non-scissors-bite side (P = 0.005). These findings suggest that scissors-bite malocclusion is associated with the masticatory chewing pattern and muscle activity, involving the choice of the preferred chewing side in patients with unilateral posterior scissors-bite.

  5. Great Balls of Fire: A probabilistic approach to quantify the hazard related to ballistics - A case study at La Fossa volcano, Vulcano Island, Italy

    NASA Astrophysics Data System (ADS)

    Biass, Sébastien; Falcone, Jean-Luc; Bonadonna, Costanza; Di Traglia, Federico; Pistolesi, Marco; Rosi, Mauro; Lestuzzi, Pierino

    2016-10-01

    We present a probabilistic approach to quantify the hazard posed by volcanic ballistic projectiles (VBP) and their potential impact on the built environment. A model named Great Balls of Fire (GBF) is introduced to describe ballistic trajectories of VBPs accounting for a variable drag coefficient and topography. It relies on input parameters easily identifiable in the field and is designed to model large numbers of VBPs stochastically. Associated functions come with the GBF code to post-process model outputs into a comprehensive probabilistic hazard assessment for VBP impacts. Outcomes include probability maps to exceed given thresholds of kinetic energies at impact, hazard curves and probabilistic isoenergy maps. Probabilities are calculated either on equally-sized pixels or zones of interest. The approach is calibrated, validated and applied to La Fossa volcano, Vulcano Island (Italy). We constructed a generic eruption scenario based on stratigraphic studies and numerical inversions of the 1888-1890 long-lasting Vulcanian cycle of La Fossa. Results suggest a ~ 10- 2% probability of occurrence of VBP impacts with kinetic energies ≤ 104 J at the touristic locality of Porto. In parallel, the vulnerability to roof perforation was estimated by combining field observations and published literature, allowing for a first estimate of the potential impact of VBPs during future Vulcanian eruptions. Results indicate a high physical vulnerability to the VBP hazard, and, consequently, half of the building stock having a ≥ 2.5 × 10- 3% probability of roof perforation.

  6. Posterior Corneal Characteristics of Cataract Patients with High Myopia

    PubMed Central

    Jing, Qinghe; Tang, Yating; Qian, Dongjin; Lu, Yi; Jiang, Yongxiang

    2016-01-01

    Purpose To evaluate the characteristics of the posterior corneal surface in patients with high myopia before cataract surgery. Methods We performed a cross-sectional study at the Eye and ENT Hospital of Fudan University, Shanghai, China. Corneal astigmatism and axial length were measured with a rotating Scheimpflug camera (Pentacam) and partial coherence interferometry (IOLMaster) in a high-myopia study group of 167 eyes (axial length ≥ 26 mm) and a control group of 150 eyes (axial length > 20 mm and < 25 mm). Results Total corneal astigmatism and anterior corneal astigmatism values were higher in the high-myopia group than in the control group. There was no significant difference in posterior corneal astigmatism between the high-myopia study group and the control group. In the study group, the mean posterior corneal astigmatism (range 0 – −0.9 diopters) was –0.29 diopters (D) ± 0.17 standard deviations (SD). The steep corneal meridian was aligned vertically (60°–120°) in 87.43% of eyes for the posterior corneal surface, and did not change with increasing age. There was a significant correlation (r = 0.235, p = 0.002) between posterior corneal astigmatism and anterior corneal astigmatism, especially when the anterior corneal surface showed with-the-rule (WTR) astigmatism (r = 0.452, p = 0.000). There was a weak negative correlation between posterior corneal astigmatism and age (r = –0.15, p = 0.053) in the high-myopia group. Compared with total corneal astigmatism values, the anterior corneal measurements alone overestimated WTR astigmatism by a mean of 0.27 ± 0.18 D in 68.75% of eyes, underestimated against-the-rule (ATR) astigmatism by a mean of 0.41 ± 0.28 D in 88.89% of eyes, and underestimated oblique astigmatism by a mean of 0.24 ± 0.13 D in 63.64% of eyes. Conclusions Posterior corneal astigmatism decreased with age and remained as ATR astigmatism in most cases of high myopia. There was a significant correlation between posterior corneal

  7. Treatment of noninfectious posterior uveitis with dexamethasone intravitreal implant

    PubMed Central

    Myung, Jane S; Aaker, Grant D; Kiss, Szilárd

    2010-01-01

    Purpose To report our experience with dexamethasone 0.7 mg sustained-release intravitreal implant (Ozurdex®; Allergan, Inc, Irvine, CA) in noninfectious posterior uveitis. Methods A retrospective chart review of patients with noninfectious uveitis treated with sustained-release dexamethasone 0.7 mg intravitreal implant was performed. Complete ophthalmic examination including signs of inflammatory activity, visual acuity, fundus photography, fluorescein angiography, optical coherence tomography, and tolerability of the implant were assessed. Results Six eyes of 4 consecutive patients treated with a total of 8 dexamethasone 0.7 mg sustained-release intravitreal implants for posterior noninfectious uveitis were included. Two patients presented with unilateral idiopathic posterior uveitis; 2 patients had bilateral posterior uveitis, one secondary to sarcoidosis and the other to Vogt-Koyanagi-Harada syndrome. All eyes showed clinical and angiographic evidence of decreased inflammation following implant placement. Mean follow-up time post-injection was 5.25 months. Four eyes received 1 and 2 eyes received 2 Ozurdex implants during the follow-up period. The duration of effect of the implant was 3 to 4 months. No serious ocular or systemic adverse events were noted during the follow-up period. Conclusions In patients with noninfectious posterior uveitis, sustained-release dexamethasone 0.7 mg intravitreal implant may be an effective treatment option for controlling intraocular inflammation. PMID:21188153

  8. Flexor Digitorum Accessorius Longus: Importance of Posterior Ankle Endoscopy

    PubMed Central

    Batista, Jorge Pablo; del Vecchio, Jorge Javier; Golanó, Pau; Vega, Jordi

    2015-01-01

    Endoscopy for the posterior region of the ankle through two portals is becoming more widespread for the treatment of a large number of conditions which used to be treated with open surgery years ago. The tendon of the flexor hallucis longus (FHL) travels along an osteofibrous tunnel between the posterolateral and posteromedial tubercles of the talus. Chronic inflammation of this tendon may lead to painful stenosing tenosynovitis. The aim of this report is to describe two cases depicting an accessory tendon which is an anatomical variation of the flexor hallucis longus in patients with posterior friction syndrome due to posterior ankle impingement and associated with a posteromedial osteochondral lesion of the talus. The anatomical variation (FDAL) described was a finding during an endoscopy of the posterior region of the ankle, and we have spared it by sectioning the superior flexor retinaculum only. The accessory flexor digitorum longus is an anatomical variation and should be taken into account when performing an arthroscopy of the posterior region of the ankle. We recommend this treatment on this type of injury although we admit this does not make a definite conclusion. PMID:26060592

  9. Arthroscopic subtalar arthrodesis: the posterior approach in the prone position.

    PubMed

    Carro, Luis Perez; Golanó, Pau; Vega, Jordi

    2007-04-01

    Arthroscopic subtalar arthrodesis, as reported by Tasto, is done in the lateral decubitus position, and the portal sites are lateral. This report describes a new alternative method in which the patient is in the prone position and a posterior 2-portal approach is used, as described by van Dijk et al. The initial debridement and synovectomy are performed with 4- and 5-mm resectors. Debridement and decortication are done posterior to the interosseous ligament because only the posterior facet is fused. Denudation of the articular surfaces is performed with curettes, as well as 4.5- and 5.5-mm burs, to remove 2 mm of subchondral bone. Stabilization in 5 degrees of hindfoot valgus is accomplished with 2 percutaneous cannulated headless screws from the non-weight-bearing portion of the calcaneal tuberosity directed to a point 5 to 10 mm posterior to the anterior margin of the posterior facet. The advantages of this alternative treatment are better intra-articular visualization, more thorough preparation of the fusion site, and minimal bone removal of the lateral side with better control of the arthrodesis position and with less chance of malunion, as well as the possibility to perform a concomitant surgical fusion or debridement of the ankle joint during the same operative procedure with no need for additional portals or orientation.

  10. Instrumented Posterior Lumbar Interbody Fusion in Adult Spondylolisthesis

    PubMed Central

    Yu, Ching-Hsiao; Wang, Chen-Ti

    2008-01-01

    It is unclear whether using artificial cages increases fusion rates compared with use of bone chips alone in posterior lumbar interbody fusion for patients with lumbar spondylolisthesis. We hypothesized artificial cages for posterior lumbar interbody fusion would provide better clinical and radiographic outcomes than bone chips alone. We assumed solid fusion would provide good clinical outcomes. We clinically and radiographically followed 34 patients with spondylolisthesis having posterior lumbar interbody fusion with mixed autogenous and allogeneic bone chips alone and 42 patients having posterior lumbar interbody fusion with implantation of artificial cages packed with morselized bone graft. Patients with the artificial cage had better functional improvement in the Oswestry disability index than those with bone chips alone, whereas pain score, patient satisfaction, and fusion rate were similar in the two groups. Postoperative disc height ratio, slip ratio, and segmental lordosis all decreased at final followup in the patients with bone chips alone but remained unchanged in the artificial cage group. The functional outcome correlated with radiographic fusion status. We conclude artificial cages provide better functional outcomes and radiographic improvement than bone chips alone in posterior lumbar interbody fusion for lumbar spondylolisthesis, although both techniques achieved comparable fusion rates. Level of Evidence: Level III, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence. PMID:18846411

  11. Biochemical and Clinical Assessments of Segmental Maxillary Posterior Tooth Intrusion

    PubMed Central

    Tasanapanont, Jintana; Wattanachai, Tanapan; Apisariyakul, Janya; Pothacharoen, Peraphan; Kongtawelert, Prachya; Midtbø, Marit

    2017-01-01

    Objective. To compare chondroitin sulphate (CS) levels around maxillary second premolars, first molars, and second molars between the unloaded and the loaded periods and to measure the rates of intrusion of maxillary posterior teeth during segmental posterior tooth intrusion. Materials and Methods. In this prospective clinical study, 105 teeth (from 15 patients exhibiting anterior open bite and requiring maxillary posterior tooth intrusion) were studied. Competitive ELISA was used to detect CS levels. Dental casts (during the unloaded and loaded periods) were scanned, and posterior tooth intrusion distances were measured. Results. During the unloaded period, the median CS levels around maxillary second premolars, first molars, second molars (experimental teeth), and mandibular first molars (negative control) were 0.006, 0.055, 0.056, and 0.012 and during the loaded period were 2.592, 5.738, 4.727, and 0.163 ng/μg of total protein, respectively. The median CS levels around experimental teeth were significantly elevated during the loaded period. The mean rates of maxillary second premolar and first and second molar intrusion were 0.72, 0.58, and 0.40 mm/12 weeks, respectively. Conclusions. Biochemical and clinical assessments suggested that the segmental posterior tooth intrusion treatment modality with 50 g of vertical force per side was sufficient. Trial Registration. The study is registered as TCTR20170206006. PMID:28321256

  12. Reversible posterior leucoencephalopathy syndrome associated with bone marrow transplantation.

    PubMed

    Teive, H A; Brandi, I V; Camargo, C H; Bittencourt, M A; Bonfim, C M; Friedrich, M L; de Medeiros, C R; Werneck, L C; Pasquini, R

    2001-09-01

    Reversible posterior leucoencephalopathy syndrome (RPLS) has previously been described in patients who have renal insufficiency, eclampsia, hypertensive encephalopathy and patients receiving immunosuppressive therapy. The mechanism by which immunosuppressive agents can cause this syndrome is not clear, but it is probably related with cytotoxic effects of these agents on the vascular endothelium. We report eight patients who received cyclosporine A (CSA) after allogeneic bone marrow transplantation or as treatment for severe aplastic anemia (SSA) who developed posterior leucoencephalopathy. The most common signs and symptoms were seizures and headache. Neurological dysfunction occurred preceded by or concomitant with high blood pressure and some degree of acute renal failure in six patients. Computerized tomography studies showed low-density white matter lesions involving the posterior areas of cerebral hemispheres. Symptoms and neuroimaging abnormalities were reversible and improvement occurred in all patients when given lower doses of CSA or when the drug was withdrawn. RPLS may be considered an expression of CSA neurotoxicity.

  13. Subjective experience, involuntary movement, and posterior alien hand syndrome

    PubMed Central

    Bundick, T; Spinella, M

    2000-01-01

    The alien hand syndrome, as originally defined, was used to describe cases involving anterior corpus callosal lesions producing involuntary movement and a concomitant inability to distinguish the affected hand from an examiner's hand when these were placed in the patient's unaffected hand. In recent years, acceptable usage of the term has broadened considerably, and has been defined as involuntary movement occurring in the context of feelings of estrangement from or personification of the affected limb or its movements. Three varieties of alien hand syndrome have been reported, involving lesions of the corpus callosum alone, the corpus callosum plus dominant medial frontal cortex, and posterior cortical/subcortical areas. A patient with posterior alien hand syndrome of vascular aetiology is reported and the findings are discussed in the light of a conceptualisation of posterior alien hand syndrome as a disorder which may be less associated with specific focal neuropathology than are its callosal and callosal-frontal counterparts.

 PMID:10601408

  14. Local estimation of posterior class probabilities to minimize classification errors.

    PubMed

    Guerrero-Curieses, Alicia; Cid-Sueiro, Jesús; Alaiz-Rodríguez, Rocío; Figueiras-Vidal, Aníbal R

    2004-03-01

    Decision theory shows that the optimal decision is a function of the posterior class probabilities. More specifically, in binary classification, the optimal decision is based on the comparison of the posterior probabilities with some threshold. Therefore, the most accurate estimates of the posterior probabilities are required near these decision thresholds. This paper discusses the design of objective functions that provide more accurate estimates of the probability values, taking into account the characteristics of each decision problem. We propose learning algorithms based on the stochastic gradient minimization of these loss functions. We show that the performance of the classifier is improved when these algorithms behave like sample selectors: samples near the decision boundary are the most relevant during learning.

  15. ‘Split posterior tooth’: conservative clinical re-attachment

    PubMed Central

    Abraham, Sathish; Chacko, Lisa Neelathil

    2014-01-01

    Trauma is the prime causative factor for fracture of teeth/dentition. Many procedural management options are followed successfully in relation to the anterior teeth. However, most posterior cases where the tooth is fractured have only limited options to pursue to save the tooth. Fractured teeth, whether they are vital/non-vital, are predominantly managed with surgical options. This paper discusses a conservative approach to reattaching a split posterior tooth. A split tooth situation is mostly an absolute indication for extraction, but the clinician may go in for extensive surgical procedures if he/she wishes to save it. The reattachment of the tooth can be successfully done and it can be put to function. This paper discusses how a split posterior tooth can be treated successfully, although depending on multiple factors. A full crown cemented after successful reattachment and root canal therapy would provide sufficient support in order for the tooth to heal. PMID:25080545

  16. Endothelin: A novel peptide in the posterior pituitary system

    SciTech Connect

    Yoshizawa, Toshihiro; Kanazawa, Ichiro; Shinmi, Osamu; Kimura, Sadao; Yanagisawa, Masashi; Masaki, Tomoh; Uchiyama, Yasuo ); Giaid, A.; Gibson, S.J.; Polak, J.M. )

    1990-01-26

    Endothelin (ET), originally characterized as a 21-residue vasoconstrictor peptide from endothelial cells, is present in the porcine spinal cord and may act as a neuropeptide. Endothelin-like immunoreactivity has now been demonstrated by immunohistochemistry in the paraventricular and supraoptic nuclear neurons and their terminals in the posterior pituitary of the pig and the rat. The presence of ET in the porcine hypothalamus was confirmed by reversed-phase high-pressure liquid chromatography and radioimmunoassay. Moreover, in situ hybridization demonstrated ET messenger RNA in porcine paraventricular nuclear neurons. Endothelin-like immunoreactive products in the posterior pituitary of the rat were depleted by water deprivation, suggesting a release of ET under physiological conditions. These findings indicate that ET is synthesized in the posterior pituitary system and may be involved in neurosecretory functions.

  17. Quantification of Posterior Globe Flattening: Methodology Development and Validation

    NASA Technical Reports Server (NTRS)

    Lumpkins, Sarah B.; Garcia, Kathleen M.; Sargsyan, Ashot E.; Hamilton, Douglas R.; Berggren, Michael D.; Ebert, Douglas

    2012-01-01

    Microgravity exposure affects visual acuity in a subset of astronauts and mechanisms may include structural changes in the posterior globe and orbit. Particularly, posterior globe flattening has been implicated in the eyes of several astronauts. This phenomenon is known to affect some terrestrial patient populations and has been shown to be associated with intracranial hypertension. It is commonly assessed by magnetic resonance imaging (MRI), computed tomography (CT) or B-mode Ultrasound (US), without consistent objective criteria. NASA uses a semiquantitative scale of 0-3 as part of eye/orbit MRI and US analysis for occupational monitoring purposes. The goal of this study was ot initiate development of an objective quantification methodology to monitor small changes in posterior globe flattening.

  18. Quantification of Posterior Globe Flattening: Methodology Development and Validationc

    NASA Technical Reports Server (NTRS)

    Lumpkins, S. B.; Garcia, K. M.; Sargsyan, A. E.; Hamilton, D. R.; Berggren, M. D.; Antonsen, E.; Ebert, D.

    2011-01-01

    Microgravity exposure affects visual acuity in a subset of astronauts, and mechanisms may include structural changes in the posterior globe and orbit. Particularly, posterior globe flattening has been implicated in several astronauts. This phenomenon is known to affect some terrestrial patient populations, and has been shown to be associated with intracranial hypertension. It is commonly assessed by magnetic resonance imaging (MRI), computed tomography (CT), or B-mode ultrasound (US), without consistent objective criteria. NASA uses a semi-quantitative scale of 0-3 as part of eye/orbit MRI and US analysis for occupational monitoring purposes. The goal of this study was to initiate development of an objective quantification methodology for posterior globe flattening.

  19. Ligamentous and capsular restraints to experimental posterior elbow joint dislocation.

    PubMed

    Deutch, Søren R; Olsen, Bo S; Jensen, Steen L; Tyrdal, Stein; Sneppen, Otto

    2003-10-01

    Pathological external forearm rotation (PEFR) relates to posterolateral elbow joint instability, and is considered a possible requisite step in a simple posterior elbow joint dislocation. The aim of this study was to evaluate the capsuloligamentous restraint to PEFR. In all, 18 elbow joint specimens were examined in a joint analysis system developed for experimental elbow dislocation. Sequential cutting of capsule and ligaments followed by stability testing provided specific data relating to each capsuloligamentous structure. The primary stabilizers against PEFR in the extended elbow were the anterior capsule and the lateral collateral ligament complex (LCLC), whereas in the flexed elbow the anterior capsule did not have a stabilizing effect. In flexed joint positions, the LCLC seems to be the only immediate stabilizer against PEFR, and thereby against posterolateral instability and possibly against posterior dislocation. The medial collateral ligament did not have any immediate stabilizing effect, but it prevented the final step of the posterior dislocation.

  20. Ossification of the posterior atlantoaxial membrane associated with atlas hypoplasia

    PubMed Central

    Meng, Yichen; Zhou, Dongxiao; Gao, Rui; Ma, Jun; Wang, Ce; Zhou, Xuhui

    2016-01-01

    Abstract Rationale: Hypoplasia with an intact posterior arch of the atlas and ossification of the posterior atlantoaxial membrane (PAAM) are individually rare. Patient concerns: The patient presented with a 6-month history of progressive weakness and paresthesia of his lower extremities. Diagnoses: Cervical myelopathy resulting from atlas hypoplasia and ossification of the posterior atlantoaxial membrane. Interventions: Laminectomy of the atlas with duroplasty. Outcomes: Preoperative symptoms were alleviated. Lessons: In most reported cases, either atlas hypoplasia or ossification of the PAAM is responsible for patients’ myelopathy. The case illustrated here, to the best of our knowledge, is the first one with coexistent atlas hypoplasia and ossification of the PAAM. And laminectomy of the atlas with duroplasty provided satisfied outcome. PMID:27902623

  1. Language Disorders due to Posterior System Strokes - An Ignored Dysfunction

    PubMed Central

    ÖZTÜRK, Şerefnur; EGE, Fahrettin; EKMEKÇİ, Hakan

    2014-01-01

    The anterior system is primarily responsible for the clinical picture in a patient that presents with clinical aphasia. However, recent reports have shown that injuries to posterior structures, the cerebellum in particular, may have a role in language processing. Herein, we will look first at the linguistic role of the cerebellum in light of the literature, then of the thalamus and some described clinical syndromes, and finally, specific syndromes resulting from occipital lobe lesions, all of which are supported by the posterior vascular system. The human brain is such a complex organization that in addition to the thalamus and occipital cortex, we can see the involvement of the cerebellum in high cognitive functions. Posterior system strokes may lead to clinical findings of cognitive deficits, including neurolinguistic components. Determining these defects in stroke patients may precipitate changes in current management strategies. PMID:28360648

  2. [Segmental posterior spinal osteosynthesis using the Luque-Dove technic].

    PubMed

    Kerboul, B; Courtois, B

    1989-03-01

    The Hartshill frame is method for segmental osteosynthesis of the spine. It is attached at each vertebral level by sub-laminal metal wires. This frame therefore ensures immediate stability and avoids the need for a post-operative corset. It enables correction of frontal deformities (scoliosis) whilst retaining sagittal physiological curves (lumbar lordosis--dorsal kyphosis). It ensures the fixation of posterior spinal instability (destruction of posterior ligaments and bone tissue, spondylolisthesis, etc.). The Hartshill frame can thus be seen to be a posterior brace. It has been used in 92 patients, (53 lumbar disorders, 10 cases of scoliosis, 4 of kyphosis, 19 tumors, 6 fractures). Results are generally entirely satisfactory in the mid term apart from fractures (recurrence of initial displacement). Specific complications are of a neurological nature (cases of cutaneous hyperesthesia, one severe motor deficit) long-term problems with device and material are uncommon; rupture of sub-laminar wire 8 cases; secondary incurving of frame 1 case.

  3. Ganglion cyst of the posterior cruciate ligament in a child.

    PubMed

    Hameed, Shamsi Abdul; Sujir, Premjit; Naik, Monappa A; Rao, Sharath K

    2012-04-01

    Ganglion cysts are more commonly associated with the anterior cruciate ligament than the posterior cruciate ligament (PCL). A literature review showed that all reported cases of ganglion cysts to date involved adults. We report a rare case of ganglion cyst in the PCL of a four-year-old boy, and discuss its aetiology, clinical presentation, imaging features and management. Ganglion cysts of the PCL may be confused with meniscal cysts arising from tears of the posterior horn of the medial meniscus on magnetic resonance (MR) imaging. Hence, the posterior horn of the medial meniscus has to be carefully evaluated to rule out a tear. MR imaging is the method of choice to confirm diagnosis, and arthroscopic resection is a safe treatment modality even in children.

  4. Posterior Wall Gastric Leiomyoma: Endoscopic Tattooing Facilitates Laparoscopic Resection

    PubMed Central

    Mehta, Dhiren; Zelen, Johnathan; Fogler, Richard

    1998-01-01

    Objective: To demonstrate the application of tattooing for the intraoperative localization of posterior wall gastric leiomyoma during laparoscopic resection. The preoperative injection of Indian ink in the tumor-bearing area of the posterior gastric wall eliminates the need to perform anterior wall gastrostomy or intraoperative upper endoscopic tumor localization. Methods: A patient with posterior wall gastric leiomyoma was marked with Indian ink during preoperative upper endoscopy. The dye was visualized intraoperatively facilitating wedge resection of the tumor-bearing area with the Endo GIA. Results: The patient had an uneventful surgery and recovery. Complete excision of the tumor was accomplished. Conclusion: The preoperative endoscopic marking of gastric lesions, facilitates the intraoperative localization and resection of these lesions. PMID:9876718

  5. Structural Position of the Posterior Vagina and Pelvic Floor in Women with and without Posterior Vaginal Prolapse

    PubMed Central

    LEWICKY-GAUPP, Christina; YOUSUF, Aisha; LARSON, Kindra A; FENNER, Dee E; DeLANCEY, John OL

    2012-01-01

    Objective Compare pelvic structure location on MRI during maximal Valsalva among women with posterior prolapse and those with normal support. Methods and Materials Cases (n=37) had posterior vaginal wall (PVW) prolapse > +1cm. All underwent mid-sagittal, dynamic MRI. Structure locations (distal vagina, apex, perineal body, external anal sphincter) were determined. PVW length, levator and urogenital hiatus diameters, and prolapse diameter were measured. Results Cases had more caudal structures (p<0.001) and larger hiatus diameters (p<0.005); the posterior wall was longer, while the straight-line distance between the apex and distal vagina was shorter. In enteroceles, the apex was more ventrally displaced compared to rectoceles (p=0.003). Unlike apical descent (r=-0.3, p=0.1), PVW length and point Bp were correlated with MRI prolapse size (r=0.5, p=0.002; r=0.7, P<0.001, respectively). Conclusion At maximal Valsalva on MRI, structures are more caudal in women with posterior prolapse. The posterior vaginal wall is longer; this length strongly correlates with prolapse size. PMID:20452497

  6. Posterior clinoidectomy: dural tailoring technique and clinical application.

    PubMed

    Youssef, A Samy; van Loveren, Harry R

    2009-05-01

    The posterior clinoid process, a bony prominence at the superolateral aspect of the dorsum sellae, has a strategic importance in a transcavernous approach to basilar tip aneurysms. To further optimize this microsurgical technique during posterior clinoidectomy, we performed a cadaveric study of this regional anatomy, describe a technique called dural tailoring, and report initial results in the surgical treatment of upper basilar artery (BA) aneurysm. After 10 adult cadaver heads (silicone-injected) were prepared for dissection, a posterior clinoidectomy with dural tailoring was performed. The dura overlying the upper clivus was coagulated with bipolar electrocoagulation and incised. Stripping dura off the clivus and lateral reflection then exposed the ipsilateral posterior clinoid process and dorsum sellae, thus creating a dural flap. Posterior clinoidectomy with dural tailoring was then used in seven patients with upper BA aneurysms. Our stepwise modification of the posterior clinoidectomy with dural tailoring created a flap that afforded protection of the cavernous sinus and oculomotor nerve. During surgery, there were no recorded intraoperative injuries to neurovascular structures. One patient died postoperatively from morbidity related to severe-grade subarachnoid hemorrhage. Postoperative oculomotor nerve palsy occurred in 3 patients (43%). In all cases, the nerve was anatomically preserved and partial to complete recovery was recorded during the first postoperative year. This technique effectively provided exposure of retrosellar upper basilar aneurysms in seven patients (basilar tip 43% and superior cerebellar artery aneurysms 57%). Outcomes and safety are at least equivalent to or better than basilar aneurysm surgery performed without surgical adjuncts, presumably a less complex subset.

  7. Teaching of posterior composites in dental schools in Japan.

    PubMed

    Hayashi, M; Seow, L L; Lynch, C D; Wilson, N H F

    2009-04-01

    The teaching of posterior composites has undergone considerable refinement and development in western countries in recent years. However, little information exists on this teaching in other parts of the world. The aim of this paper is to investigate the teaching of posterior composites to undergraduate dental students in Japan. In late 2007/early 2008, a questionnaire seeking information on the teaching of posterior composites was distributed by email to the person responsible for teaching operative dentistry in each of the 29 dental schools having undergraduate dental degree programmes in Japan. Twenty-three completed responses were returned (response rate = 79%). While all 23 schools taught the placement of composite in occlusal cavities in premolars and molars, 7 schools did not teach the placement of two-surface occlusoproximal composites in premolars (n = 1) and molars (n = 6) and 14 schools and 15 schools do not teach placement of three surface occlusoproximal composites in premolars and molars, respectively. While composite at the time of the survey accounted for 45% of posterior direct restorations placed by students, it is anticipated that this proportion will increase to 59% in 5 years time. Variations were noted between schools in the teaching of principles of cavity design, techniques for restoring proximal contours and light-curing technologies; however, more consistency was observed in techniques used for protecting operatively exposed dentine than that observed in western countries. Despite variations between dental schools being noted in the teaching of certain techniques for posterior composites, the overall extent and content of teaching of posterior composites in Japan could be described as comparable, if not exceeding, than that observed in western countries.

  8. Posterior tibial vein aneurysm presenting as tarsal tunnel syndrome.

    PubMed

    Ayad, Micheal; Whisenhunt, Anumeha; Hong, EnYaw; Heller, Josh; Salvatore, Dawn; Abai, Babak; DiMuzio, Paul J

    2015-06-01

    Tarsal tunnel syndrome is a compressive neuropathy of the posterior tibial nerve within the tarsal tunnel. Its etiology varies, including space occupying lesions, trauma, inflammation, anatomic deformity, iatrogenic injury, and idiopathic and systemic causes. Herein, we describe a 46-year-old man who presented with left foot pain. Work up revealed a venous aneurysm impinging on the posterior tibial nerve. Following resection of the aneurysm and lysis of the nerve, his symptoms were alleviated. Review of the literature reveals an association between venous disease and tarsal tunnel syndrome; however, this report represents the first case of venous aneurysm causing symptomatic compression of the nerve.

  9. Posture and posterior crossbite in oral and nasal breathing children.

    PubMed

    Costa, Jecilene Rosana; Pereira, Silvia Regina Amorim; Pignatari, Shirley S N; Weckx, Luc Louis Maurice

    2010-01-01

    The most known etiologic factors of oral breathing may influence the craniofacial development leading to anatomical and functional alterations. A proper head and cervical spine posture allows a well functioning of the stomatognathic system structures and vice versa. This study was conducted to evaluate the prevalence of posterior crossbite in a group of oral breathing children (OB) and nasal (NB) and associate the type of bite with the head and cervical spine posture. It was concluded that most of the children, either oral or nasal breathers, did not present a crossbite and any kind of head posture and cervical spine can vary independently of a posterior crossbite.

  10. Posterior dislocation of the sternoclavicular joint: report of two cases.

    PubMed

    Labronici, Pedro José; Souza, Fabrício Cardoso de; Pires, Robinson Esteves Santos; Santos Filho, Fernando Claudino Dos; Gameiro, Vinicius Schott; Labronici, Gustavo José

    2016-01-01

    The authors report the cases of two young patients who had suffered a sporting accident with posterior traumatic dislocation of sternoclavicular joint. In one of the patients closed reduction was accomplished by keeping the limb in a sling. The second patient, after reduction was done, presented recurrence of the dislocation, thus requiring surgical treatment. It is important to observe the relevance of computed tomography to help diagnosing, as well as monitoring the reduction procedure. The objective of this study was to demonstrate two different types of treatment in a rare injury such as the posterior dislocation of sternoclavicular joint.

  11. Posterior shoulder dislocation while lifting weights: a missed diagnosis

    PubMed Central

    Cuffolo, Giulio; Coomber, Ross; Burtt, Simon; Gray, Jim

    2014-01-01

    Summary We present a case of a 24-year-old man who suffered acute shoulder pain and subsequent inability to move his arm while lifting weights in the bench-press position. He attended A&E where he was examined and X-rays were performed. He was diagnosed with presumed pectoralis major tendon rupture and was discharged to fracture clinic the following day with analgesia. On review in clinic he was found to have a posterior shoulder dislocation and was taken to theatre for relocation under anaesthesia. This case report examines the mechanism, investigations and management of posterior shoulder dislocation. PMID:24557475

  12. Management of Posterior Reversible Syndrome in Preeclamptic Women

    PubMed Central

    Poma, S.; Delmonte, M. P.; Gigliuto, C.; Imberti, R.; Delmonte, M.; Arossa, A.; Iotti, G. A.

    2014-01-01

    Posterior reversible encephalopathy syndrome (PRES) is a neurological syndrome associated with a number of conditions including preeclampsia. It is characterized by seizures, alteration of consciousness, visual disturbances, and symmetric white matter abnormalities, typically in the posterior parietooccipital regions of the cerebral hemispheres, at computed tomography (CT) and magnetic resonance (MRI). We report three new cases of PRES in preeclamptic patients and describe the management of these patients. We present a brief review of other cases in the literature, with particular attention to the anesthetic management. PMID:25506009

  13. Spectral domain optical coherence tomography finding in posterior microphthalmos.

    PubMed

    Kumar, Mukesh; Das, Taraprasad; Kesarwani, Siddharth

    2012-11-01

    An eight-year-old boy presented with decreased vision in both eyes. At presentation, the visual acuity was 6/60 in both eyes with high plus spheres. Anterior segment examination was normal. Fundus examination and spectral domain optical coherence tomography were consistent with posterior microphthalmos and showed an elevated foveal contour and fold in the outer plexiform layer. External limiting membrane, photoreceptor and retinal pigment epithelium were not involved in the fold. To the best of our knowledge this is the first such case report with optical coherence tomography imaging of the retinal layer involved in a case of posterior microphthalmos.

  14. Recanalization of an occluded popliteal artery following posterior knee dislocation.

    PubMed

    Kirby, L; Abbas, J; Brophy, C

    1999-11-01

    Posterior knee dislocation results in popliteal artery injury in up to one-third of cases. Prompt recognition and treatment of arterial injury is essential for limb salvage. We report a case of complete occlusion of the popliteal artery following posterior knee dislocation treated with saphenous vein bypass without exclusion of the injured arterial segment. Follow-up duplex scanning demonstrated a patent vein graft and a patent ipsilateral popliteal artery. This report suggests that, in some instances, a traumatically occluded popliteal artery may recanalize, and that revascularization with a bypass graft may be the preferred method of repair, particularly in young patients.

  15. Bilateral epididymitis in a child with undiagnosed posterior urethral valves.

    PubMed

    Kwong, Justin; Lorenzo, Armando J; DeMaria, Jorge; Braga, Luis H P

    2013-07-01

    Posterior urethral valves are most commonly detected in the early neonatal period, the diagnosis often antenatally suspected from ultrasound findings. Nevertheless, some cases might go undetected and become manifest later in life with lower urinary tract symptoms. We describe the unusual case of a 5-year-old boy with a 2-month history of bladder distension, urinary dribbling, and epididymitis. Cystourethrography revealed posterior urethral valves with reflux into the seminal vesicles, vas deferens, and epididymis, bilaterally. A review of the published data is provided in the context of this unusual presentation pattern.

  16. Double triangular resection for a widely prolapsed posterior mitral leaflet†

    PubMed Central

    Sawazaki, Masaru; Tomari, Shiro; Tsunekawa, Tomohiro; Izawa, Naoto

    2013-01-01

    A wide and redundant prolapse of the posterior mitral leaflet in active infective endocarditis cannot be easily repaired. A sliding plasty can be attempted, but the range of annular plication is often too large. Chordal replacement is another option, but is prone to long-term degeneration because the redundant leaflet still exists. Here, we describe a simple resection technique that utilizes only two small triangular resections. The resections are sutured with no need to shorten the annulus. The leaflet tissue between the two triangular resections must be preserved to make an appropriately shaped posterior leaflet. PMID:23223672

  17. Recurrent Massive Epistaxis from an Anomalous Posterior Ethmoid Artery

    PubMed Central

    Mattioli, Francesco; Alberici, Maria Paola; Presutti, Livio

    2016-01-01

    A 50-year-old man, with no previous history of epistaxis, was hospitalized at our facility for left recurrent posterior epistaxis. The patient underwent surgical treatment three times and only the operator's experience and radiological support (cranial angiography) allowed us to control the epistaxis and stop the bleeding. The difficult bleeding management and control was attributed to an abnormal course of the left posterior ethmoidal artery. When bleeding seems to come from the roof of the nasal cavity, it is important to identify the ethmoid arteries always bearing in mind the possible existence of anomalous courses. PMID:28025632

  18. Stability of unsaturated pyroclastic deposits at La Fossa flank (Vulcano Island, Italy): Do soil suction variations establish a link with crater degassing ?

    NASA Astrophysics Data System (ADS)

    Olivares, L.; Tommasi, P.; Madonia, P.; Moretti, R.

    2012-04-01

    The stability of steep ( > 40°) slopes in loose or poorly cemented pyroclastic materials mantling some of the Italian mountain areas is guaranteed by the positive effects of matrix suction on shear strength until an increase in saturation (and hence a decrease in suction) occurs. Therefore, unsaturated cohesionless or slightly-bonded pyroclastic steep deposits are relatively stable. Slope instability, initiated by wetting, can occur through different processes, such as vapor condensation and, most typically, rainfall infiltration. The main effect is the decrease in suction up to possible development of positive pore pressures. Here, we examine the peculiar case of a landslide on the flank of the pyroclastic cone of La Fossa volcanic edifice in Vulcano Island (Aeolian Archipelago, Southern Italy). Its initiation is believed to have been influenced by a sharp increase in condensed vapor produced by the degassing of the active volcano. In active volcanoes hydraulic conditions are affected not only by infiltrating rainwater but also by volcanic activity, which produces complex changes in the state variables of pore fluids (i.e. pore fluid pressure). In particular, volcanic activity can modify pore fluid pressure as far as to induce slope instability. At La Fossa crater the phenomenon was evidenced by in situ monitoring of soil suction and soil temperature. In situ observations and measurements indicate that seepage of condensed vapor is appreciable. Simple models based on the geotechnical characterization of pyroclastic materials suggest the hypothesis that variations in suction can be significant to stability of volcano slopes when these are very close to limit conditions and if material hydraulic anisotropy is considered. Noteworthy, at La Fossa at Vulcano Island steam condensation increased and variations of chemical ratios at fumaloles occurred while large slope movements developed on the NE flank of the cone during the most intense well documented volcanic unrest

  19. Posterior Trans-Dural Repair of Iatrogenic Spinal Cord Herniation after Resection of Ossification of Posterior Longitudinal Ligament

    PubMed Central

    Kim, Hong-Ki; Kim, Ki-Jeong; Jahng, Tae-Ahn; Kim, Hyun-Jib

    2016-01-01

    Iatrogenic spinal cord herniation is a rare complication following spinal surgery. We introduce a posterior trans-dural repair technique used in a case of thoracic spinal cord herniation through a ventral dural defect following resection of ossification of the posterior longitudinal ligament (OPLL) in the cervicothoracic spine. A 51-year-old female was suffering from paraplegia after laminectomy alone for cervicothoracic OPLL. Magnetic resonance imaging revealed a severely compressed spinal cord with pseudomeningocele identified postoperatively. Cerebrospinal fluid leak and iatrogenic spinal cord herniation persisted despite several operations with duroplasty and sealing agent. Finally, the problems were treated by repair of the ventral dural defect with posterior trans-dural duroplasty. Several months after surgery, the patient could walk independently. This surgical technique can be applied to treat ventral dural defect and spinal cord herniation. PMID:27114779

  20. Posterior Predictive Assessment of Item Response Theory Models

    ERIC Educational Resources Information Center

    Sinharay, Sandip; Johnson, Matthew S.; Stern, Hal S.

    2006-01-01

    Model checking in item response theory (IRT) is an underdeveloped area. There is no universally accepted tool for checking IRT models. The posterior predictive model-checking method is a popular Bayesian model-checking tool because it has intuitive appeal, is simple to apply, has a strong theoretical basis, and can provide graphical or numerical…

  1. Bilateral posterior shoulder dislocation after electrical shock: A case report

    PubMed Central

    Ketenci, Ismail Emre; Duymus, Tahir Mutlu; Ulusoy, Ayhan; Yanik, Hakan Serhat; Mutlu, Serhat; Durakbasa, Mehmet Oguz

    2015-01-01

    Introduction Posterior dislocation of the shoulder is a rare and commonly missed injury. Unilateral dislocations occur mostly due to trauma. Bilateral posterior shoulder dislocations are even more rare and result mainly from epileptic seizures. Electrical injury is a rare cause of posterior shoulder dislocation. Injury mechanism in electrical injury is similar to epileptic seizures, where the shoulder is forced to internal rotation, flexion and adduction. Presentation of case This report presents a case of bilateral posterior shoulder dislocation after electrical shock. We were able to find a few individual case reports describing this condition. The case was acute and humeral head impression defects were minor. Our treatment in this case consisted of closed reduction under general anesthesia and applying of orthoses which kept the shoulders in abduction and external rotation. A rehabilitation program was begun after 3 weeks of immobilization. After 6 months of injury the patient has returned to work. 20 months postoperatively, at final follow-up, he was painless and capable of performing all of his daily activities. Discussion The amount of bilateral shoulder dislocations after electrical injury is not reported but is known to be very rare. The aim of this case presentation is to report an example for this rare entity, highlight the difficulties in diagnosis and review the treatment options. Conclusion Physical examination and radiographic evaluation are important for quick and accurate diagnosis. PMID:26904192

  2. Missed C1 posterior arch fracture: a case report

    PubMed Central

    Munro, Donald S

    1990-01-01

    A case of a C1 posterior arch fracture following a fall is presented. The need to perform a thorough history and examination, regardless of previous examination findings, is emphasized. This is especially true when there is a history of recent trauma. A brief discussion of the characteristics and management of C1 fractures follows. ImagesFigure 1Figure 2Figure 3

  3. Covering Your Posterior: Teaching Signaling Games Using Classroom Experiments

    ERIC Educational Resources Information Center

    Turocy, Theodore L.

    2009-01-01

    The author describes a protocol for classroom experiments for courses that introduce undergraduates to signaling games. Signaling games are conceptually difficult because, when analyzing the game, students are not naturally inclined to think in probabilistic, Bayesian terms. The experimental design explicitly presents the posterior frequencies of…

  4. Atrial natriuretic factor-like activity in rat posterior pituitary

    SciTech Connect

    Gutkowska, J.; Debinski, W.; Racz, K.; Thibault, G.; Garcia, R.; Kuchel, O.; Genest, J.; Cantin, M.

    1986-03-05

    The presence of a biologically active peptide: Atrial Natriuretic Factor (ANF) has been demonstrated in rat and human circulation and ANF is considered now as a new hormone. ANF may be involved in body fluid regulation. A very sensitive radioimmunoassay for rat ANF allowed the authors to search for immunoreactive ANF (IR-ANF) in rat posterior pituitary. Serial dilutions of homogenates of rat posterior pituitary showed a good parallelism with a reference curve in a radioimmunoassay system. The IR-ANF was extracted from rat posterior pituitary homogenates by activated Vycor glass beads. The lyophilized extract was purified by HPLC on C/sub 18/ ..mu.. Bondapak column. The HPLC yielded two IR-ANF peaks. Both isolated ANF-like material showed biological activity. The IR-ANF eluted with 33% acetonitrile, inhibited ACTH-stimulated aldosterone secretion with a similar potency as synthetic (Arg 101 - Tyr 126) ANF (0.7 x 10/sup -10/M). A much less potent ANF-like material was found in the second peak eluted with 36% acetonitrile. They conclude that ANF-like material is present in rat posterior pituitary and this suggest a possible role in ANF on AVP secretion directly in situ.

  5. Multiclass Posterior Probability Twin SVM for Motor Imagery EEG Classification.

    PubMed

    She, Qingshan; Ma, Yuliang; Meng, Ming; Luo, Zhizeng

    2015-01-01

    Motor imagery electroencephalography is widely used in the brain-computer interface systems. Due to inherent characteristics of electroencephalography signals, accurate and real-time multiclass classification is always challenging. In order to solve this problem, a multiclass posterior probability solution for twin SVM is proposed by the ranking continuous output and pairwise coupling in this paper. First, two-class posterior probability model is constructed to approximate the posterior probability by the ranking continuous output techniques and Platt's estimating method. Secondly, a solution of multiclass probabilistic outputs for twin SVM is provided by combining every pair of class probabilities according to the method of pairwise coupling. Finally, the proposed method is compared with multiclass SVM and twin SVM via voting, and multiclass posterior probability SVM using different coupling approaches. The efficacy on the classification accuracy and time complexity of the proposed method has been demonstrated by both the UCI benchmark datasets and real world EEG data from BCI Competition IV Dataset 2a, respectively.

  6. The posterior meniscofemoral ligament: morphologic study and anatomic classification.

    PubMed

    Han, Seung-Ho; Kim, Deog-Im; Choi, Seung-Gyu; Lee, Jun-Hee; Kim, Yi-Suk

    2012-07-01

    The meniscofemoral ligaments (MFLs) run from the medial femoral condyle to the posterior horn of the lateral meniscus and consist of anterior MFL (aMFL) and/or posterior MFL (pMFL) components according to whether it passes anterior or posterior to the posterior cruciate ligament (PCL). The purpose of this study was to analyze the incidence and morphologic features of the MFLs in Koreans and formulate an anatomic classification system of MFLs to aid the detailed interpretation of medical imaging or biomechanical data. One hundred knees from 52 cadavers were studied. Eighty-seven knees had pMFLs, whereas an aMFL was only found in one knee from a male cadaver. The pMFLs and PCLs were longer in males than in females (P < 0.05). The most common type of MFL was the high crossing of a typical pMFL against the PCL in both genders. Regarding other types, the incidence of absent pMFLs was higher in males than in females and the oblique bundle of the PCL was easily confused with the pMFL in several cases in both genders. These results provide the basis for the classification system of the MFL and will contribute to better outcomes for evaluating the MFL and PCL when using medical imaging such as arthro-CT scan or MRI through a better understanding of the anatomy of the MFL and PCL.

  7. Learning about Posterior Probability: Do Diagrams and Elaborative Interrogation Help?

    ERIC Educational Resources Information Center

    Clinton, Virginia; Alibali, Martha W.; Nathan, Mitchell J.

    2016-01-01

    To learn from a text, students must make meaningful connections among related ideas in that text. This study examined the effectiveness of two methods of improving connections--elaborative interrogation and diagrams--in written lessons about posterior probability. Undergraduate students (N = 198) read a lesson in one of three questioning…

  8. Roseomonas spinal epidural abscess complicating instrumented posterior lumbar interbody fusion.

    PubMed

    Maraki, Sofia; Bantouna, Vasiliki; Lianoudakis, Efstratios; Stavrakakis, Ioannis; Scoulica, Efstathia

    2013-07-01

    The first case of a spinal epidural abscess caused by Roseomonas mucosa following instrumented posterior lumbar fusion is presented. Although rare, because of its highly resistant profile, Roseomonas species should be included in the differential diagnosis of epidural abscesses in both immunocompromised and immunocompetent hosts.

  9. Distinguishing torpedo maculopathy from similar lesions of the posterior segment.

    PubMed

    Villegas, Victor M; Schwartz, Stephen G; Flynn, Harry W; Capó, Hilda; Berrocal, Audina M; Murray, Timothy G; Harbour, J William

    2014-01-01

    Torpedo maculopathy is a congenital solitary, oval-shaped lesion typically located temporal to the center of the macula. Congenital hypertrophy of the retinal pigment epithelium (RPE), RPE lesions of Gardner syndrome, and other lesions can present with similar characteristics. Because of its unique clinical and imaging features, torpedo maculopathy generally can be differentiated from other posterior segment lesions.

  10. Posterior Predictive Model Checking for Multidimensionality in Item Response Theory

    ERIC Educational Resources Information Center

    Levy, Roy; Mislevy, Robert J.; Sinharay, Sandip

    2009-01-01

    If data exhibit multidimensionality, key conditional independence assumptions of unidimensional models do not hold. The current work pursues posterior predictive model checking, a flexible family of model-checking procedures, as a tool for criticizing models due to unaccounted for dimensions in the context of item response theory. Factors…

  11. FEMORAL INSERTION OF THE POSTERIOR CRUCIATE LIGAMENT: AN ANATOMICAL STUDY

    PubMed Central

    de Paula Leite Cury, Ricardo; Severino, Nilson Roberto; Camargo, Osmar Pedro Arbix; Aihara, Tatsuo; Neto, Leopoldo Viana Batista; Goarayeb, Dedley Nelson

    2015-01-01

    Objective: To identify objective parameters to guide correct location of the posterior cruciate ligament (PCL) in the femur. Methods: The PCLs of 20 human cadavers were resected. The following portions were measured: distance from the most distal portion of the PCL, close to the roof, to the most anterior edge of the cartilage (AB); distance from the most proximal portion of the PCL, close to the roof, to the most anterior cartilage (AC); distance between the two parts of the ligament close to the roof (BC); distance from the distal edge in its posterior portion, to the more posterior joint edge (DE); distance from the distal edge of the ligament in its posterior portion, to the intercondylar roof (DF); and finally, the format of the ligament insertion and area of coverage on the femoral condyle. Results: The PCL has the shape of a quarter ellipse, with an average area of 153.5mm2. The mean distances found were: AB of 2.1mm, AC of 10.7mm, BC of 8.6mm DE of 12.4mm and DF of 16.8mm. Conclusions: The edge close to the roof of the anterolateral bundle is closer to the joint cartilage (2.1mm) than the posteromedial bundle is, which is 12.4mm from the edge proximal to the cartilage. These references should assist in better and more accurate positioning of femoral tunnels in PCL reconstruction. PMID:27027059

  12. Trypan blue-assisted posterior capsulorhexis in pediatric cataract surgery

    PubMed Central

    Lotfy, Ayman; Abdelrahman, Ayman

    2017-01-01

    Purpose To evaluate the safety and efficacy of staining the posterior capsule with trypan blue during capsulorhexis in pediatric cataract surgery. Patients and methods This was a prospective randomized comparative study carried out at Alpha Vision Center, Zagazig, Egypt. This study included 2 groups of children with pediatric cataract randomly allocated to undergo irrigation and aspiration. In the trypan group, which included 11 eyes, trypan blue was used to stain the posterior capsule during posterior capsulorhexis. In the control group, which included 10 eyes, no staining was performed. All surgeries were performed by the same surgeon. The 2 groups were compared for criteria such as completion of capsulorhexis, disruption of vitreous face and in-the-bag intraocular lens implantation. Results This study included 21 eyes of 16 patients (age range: 6 months–4 years). A statistically significant difference was observed for the following parameters between the 2 groups: capsulorhexis completion (P=0.04), vitreous face disruption (P=0.01) and in-the-bag intraocular lens implantation (P=0.022). Conclusion This study suggests that staining of the posterior capsule during capsulorhexis in pediatric cataract operation gives better results than capsulorhexis without staining. The stain changes the capsule texture making capsulorhexis easier with fewer complications. PMID:28182152

  13. Tibialis posterior tendon rupture: a cause of rheumatoid flat foot.

    PubMed

    Downey, D J; Simkin, P A; Mack, L A; Richardson, M L; Kilcoyne, R F; Hansen, S T

    1988-03-01

    Flat foot, a major cause of foot pain and disability, may result from rupture of the tibialis posterior tendon. We describe 2 patients with rheumatoid arthritis who developed flat feet secondary to surgically confirmed tendon rupture, and we discuss the anatomy and diagnosis of this condition. In the second patient, we also present the results of tendon imaging with both magnetic resonance and ultrasound.

  14. Accuracy of Posterior Subtalar Joint Injection Without Fluoroscopy

    PubMed Central

    Kirk, Kevin L.; Campbell, John T.; Guyton, Gregory P.

    2008-01-01

    Injection into the posterior subtalar joint has not been validated for accuracy using radiographic end points. We asked whether needle placement into a normal posterior subtalar joint could be performed accurately and selectively by experienced surgeons without fluoroscopic guidance. Three fellowship-trained orthopaedic foot and ankle surgeons each injected the posterior subtalar joint of 20 cadaveric specimens using an anterolateral approach. Fluoroscopic images were obtained by an independent investigator and blinded. A separate fellowship-trained foot and ankle surgeon interpreted the images. Of 60 injections, 58 were accurate and two were extraarticular based on interpretation by an independent foot and ankle surgeon. Extravasation into the ankle occurred in 14 samples and into the peroneal sheath in two samples. Experienced surgeons can place intraarticular injections into a radiographically normal posterior subtalar joint without fluoroscopy with a high degree of accuracy. However, extravasation into the ankle or peroneal tendon sheath occurred in an unpredictable fashion, suggesting selectivity of injection placement is relatively limited without the use of fluoroscopy. Fluoroscopy may not be necessary for injections used solely for therapeutic purposes. However, if the injection is intended for diagnostic purposes or to assist in surgical decision-making or if the joint is abnormal, we recommend fluoroscopy to ensure the subtalar joint is the only anatomic structure impacted by the injection. PMID:18404293

  15. Posterior crossbite and temporomandibular disorders (TMDs): need for orthodontic treatment?

    PubMed

    Thilander, Birgit; Bjerklin, Krister

    2012-12-01

    The aim of this work was to update the bibliography regarding the concept of 'temporomandibular disorder (TMD)' and 'posterior crossbite' and try to find out if there is any association between some special signs/symptoms of TMD and type of posterior crossbite. A literature search from 1970 to 2009, due to specified criterion, resulted in 14 publications that were found to be relevant for the present systematic review. An association between TMD and posterior crossbite (Yes-group) was reported as often as absence of such a relationship (No-group). The samples in the two groups showed similarities as well as differences with respect to number, gender, and age. Most articles reported only on 'presence' or 'absence' of crossbite and only few on type of crossbite opposite to a thorough account of clinical signs and symptoms of TMD. This review seems, however, to state that a functional posterior crossbite (mandibular guidance with midline deviation) is associated with headache, temporomandibular joint and muscular pain, and clicking. As evident from the discussion, such type needs orthodontic treatment to rehabilitate the asymmetric muscular activity between the crossbite and non-crossbite sides and the changed condyle/temporal relationship caused by mandibular deviation. Whether this treatment also will avoid future TMD problems can be answered only after clinical follow-up studies have been performed.

  16. Anterior and posterior corneal stroma elasticity assessed using nanoindentation

    PubMed Central

    Dias, Janice; Ziebarth, Noël M.

    2013-01-01

    Corneal biomechanics is an essential parameter for developing diagnostic and treatment methods of corneal-related diseases. It is widely accepted that corneal mechanical strength stems from the stroma's collagenous composition. However, more comprehensive insight into the mechanical properties within the stroma is needed to improve current corneal diagnostic and treatment techniques. The purpose of this study was to perform elasticity characterization of anterior and posterior stromal regions of human corneas using atomic force microscopy (AFM). Nine pairs of human whole globes were placed in 20% Dextran solution, cornea side down, to restore the corneal thickness to physiological levels (400-600μm). The epithelium and Bowman's membrane were removed from all eyes. Anterior stromal AFM elasticity testing was then performed on left (OS) eyes. Additional stroma was removed from right (OD) eyes to allow posterior stromal measurements at a depth of 50% of the original thickness. All experiments were performed with corneas submerged in 15% Dextran to maintain corneal hydration. The results of the study showed that the Young's modulus of elasticity of the anterior stroma (average: 281 ± 214kPa; range: 59-764kPa) was significantly higher than that of the posterior stroma (average: 89.5 ± 46.1kPa; range: 29-179kPa) (p=0.014). In addition, a linear relationship was found between the posterior stromal elasticity and anterior stromal elasticity (p=0.0428). On average, the elasticity of the posterior stroma is 39.3% of the anterior stroma. In summary, there appears to be an elasticity gradient within the corneal stroma, which should be considered in the design and development of corneal diagnostic and treatment methods to enhance efficacy. PMID:23800511

  17. Morphofunctional Compensation of Masseter Muscles in Unilateral Posterior Crossbite Patients

    PubMed Central

    Cutroneo, G.; Vermiglio, G.; Centofanti, A.; Rizzo, G.; Runci, M.; Favaloro, A.; Piancino, M.G.; Bracco, P.; Ramieri, G.; Bianchi, F.; Speciale, F.; Arco, A.; Trimarchi, F.

    2016-01-01

    Unilateral posterior crossbite is a widespread, asymmetric malocclusion characterized by an inverse relationship of the upper and lower buccal dental cusps, in the molar and premolar regions, on one side only of the dental arch. Patients with unilateral posterior crossbite exhibit an altered chewing cycles and the crossbite side masseter results to be less active with respect to the contralateral one. Few studies about morphological features of masticatory muscle in malocclusion disorders exist and most of these have been performed on animal models. The aim of the present study was to evaluate morphological and protein expression characteristics of masseter muscles in patients affected by unilateral posterior crossbite, by histological and immunofluorescence techniques. We have used antibody against PAX-7, marker of satellite cells, and against α-, β-, γ-, δ-, ε- and ζ-sarcoglycans which are transmembrane glycoproteins involved in sarcolemma stabilization. By statistical analysis we have evaluated differences in amount of myonucley between contralateral and ipsilateral side. Results have shown: i) altered fibers morphology and atrophy of ipsilateral muscle if compared to the contralateral one; ii) higher number of myonuclei and PAX-7 positive cells in contralateral side than ipsilateral one; iii) higher pattern of fluorescence for all tested sarcoglycans in contralateral side than ipsilateral one. Results show that in unilateral posterior crossbite hypertrophic response of contralateral masseter and atrophic events in ipsilateral masseter take place; by that, in unilateral posterior crossbite malocclusion masticatory muscles modify their morphology depending on the function. That could be relevant in understanding and healing of malocclusion disorders; in fact, the altered balance about structure and function between ipsilateral and contralateral muscles could, long-term, lead and/ or worsen skeletal asymmetries. PMID:27349311

  18. Posterior Eye Shape Measurement With Retinal OCT Compared to MRI

    PubMed Central

    Kuo, Anthony N.; Verkicharla, Pavan K.; McNabb, Ryan P.; Cheung, Carol Y.; Hilal, Saima; Farsiu, Sina; Chen, Christopher; Wong, Tien Y.; Ikram, M. Kamran; Cheng, Ching Y.; Young, Terri L.; Saw, Seang M.; Izatt, Joseph A.

    2016-01-01

    Purpose Posterior eye shape assessment by magnetic resonance imaging (MRI) is used to study myopia. We tested the hypothesis that optical coherence tomography (OCT), as an alternative, could measure posterior eye shape similarly to MRI. Methods Macular spectral-domain OCT and brain MRI images previously acquired as part of the Singapore Epidemiology of Eye Diseases study were analyzed. The right eye in the MRI and OCT images was automatically segmented. Optical coherence tomography segmentations were corrected for optical and display distortions requiring biometry data. The segmentations were fitted to spheres and ellipsoids to obtain the posterior eye radius of curvature (Rc) and asphericity (Qxz). The differences in Rc and Qxz measured by MRI and OCT were tested using paired t-tests. Categorical assignments of prolateness or oblateness using Qxz were compared. Results Fifty-two subjects (67.8 ± 5.6 years old) with spherical equivalent refraction from +0.50 to −5.38 were included. The mean paired difference between MRI and original OCT posterior eye Rc was 24.03 ± 46.49 mm (P = 0.0005). For corrected OCT images, the difference in Rc decreased to −0.23 ± 2.47 mm (P = 0.51). The difference between MRI and OCT asphericity, Qxz, was −0.052 ± 0.343 (P = 0.28). However, categorical agreement was only moderate (κ = 0.50). Conclusions Distortion-corrected OCT measurements of Rc and Qxz were not statistically significantly different from MRI, although the moderate categorical agreement suggests that individual differences remained. This study provides evidence that with distortion correction, noninvasive office-based OCT could potentially be used instead of MRI for the study of posterior eye shape. PMID:27409473

  19. Posterior Capsular Opacification in Preschool- and School-Age Patients after Pediatric Cataract Surgery without Posterior Capsulotomy

    PubMed Central

    Batur, Muhammed; Gül, Adem; Seven, Erbil; Can, Ertuğrul; Yaşar, Tekin

    2016-01-01

    Objectives: We aimed to evaluate the development of posterior capsular opacification (PCO) in preschool- and school-age children with cataract who underwent cataract surgery without posterior capsulotomy and anterior vitrectomy. Materials and Methods: The records of 30 eyes of 21 patients who underwent pediatric cataract surgery and intraocular lens (IOL) implantation were retrospectively reviewed. Patients’ age, PCO status and duration, need for neodymium-doped yttrium aluminium garnet (Nd:YAG) laser treatment based on coverage of visual axis, and follow-up period were recorded. Results: The mean age of the patients was 7.6±2.83 (4-12) years. Unilateral cataract surgery and IOL implantation were performed in 12 patients (57.14%) and bilateral cataract surgery and IOL implantation were performed in nine patients (42.86%). Average follow-up time was 17.7±22.67 (3-83) months. PCO developed in 21 eyes (70%) and covered the visual axis in 15 eyes (50%), which therefore required Nd:YAG laser posterior capsulotomy. The mean duration of postoperative PCO development was 8.91±18.7 months (1 week-71 months). Conclusion: We believe that with adequately experienced surgeons, performing both cataract surgery and posterior capsulotomy with anterior vitrectomy in the same session is appropriate for selected preschool- and school-age children with cataract. PMID:28058161

  20. Posterior arch C-1 screw technique: a cadaveric comparison study.

    PubMed

    Moisi, Marc; Fisahn, Christian; Tkachenko, Lara; Jeyamohan, Shiveindra; Reintjes, Stephen; Grunert, Peter; Norvell, Daniel C; Tubbs, R Shane; Page, Jeni; Newell, David W; Nora, Peter; Oskouian, Rod J; Chapman, Jens

    2017-03-17

    OBJECTIVE Posterior atlantoaxial stabilization and fusion using C-1 lateral mass screw fixation has become commonly used in the treatment of instability and for reconstructive indications since its introduction by Goel and Laheri in 1994 and modification by Harms in 2001. Placement of such lateral mass screws can be challenging because of the proximity to the spinal cord, vertebral artery, an extensive venous plexus, and the C-2 nerve root, which overlies the designated starting point on the posterior center of the lateral mass. An alternative posterior access point starting on the posterior arch of C-1 could provide a C-2 nerve root-sparing starting point for screw placement, with the potential benefit of greater directional control and simpler trajectory. The authors present a cadaveric study comparing an alternative strategy (i.e., a C-1 screw with a posterior arch starting point) to the conventional strategy (i.e., using the lower lateral mass entry site), specifically assessing the safety of screw placement to preserve the C-2 nerve root. METHODS Five US-trained spine fellows instrumented 17 fresh human cadaveric heads using the Goel/Harms C-1 lateral mass (GHLM) technique on the left and the posterior arch lateral mass (PALM) technique on the right, under fluoroscopic guidance. After screw placement, a CT scan was obtained on each specimen to assess for radiographic screw placement accuracy. Four faculty spine surgeons, blinded to the surgeon who instrumented the cadaver, independently graded the quality of screw placement using a modified Upendra classification. RESULTS Of the 17 specimens, the C-2 nerve root was anatomically impinged in 13 (76.5%) of the specimens. The GHLM technique was graded Type 1 or 2, which is considered "acceptable," in 12 specimens (70.6%), and graded Type 3 or 4 ("unacceptable") in 5 specimens (29.4%). In contrast, the PALM technique had 17 (100%) of 17 graded Type 1 or 2 (p = 0.015). There were no vertebral artery injuries found

  1. The posterior neural plate in axolotl gives rise to neural tube or turns anteriorly to form somites of the tail and posterior trunk.

    PubMed

    Taniguchi, Yuka; Kurth, Thomas; Weiche, Susanne; Reichelt, Saskia; Tazaki, Akira; Perike, Srikanth; Kappert, Verena; Epperlein, Hans-Henning

    2017-02-15

    Classical grafting experiments in the Mexican axolotl had shown that the posterior neural plate of the neurula is no specified neuroectoderm but gives rise to somites of the tail and posterior trunk. The bipotentiality of this region with neuromesodermal progenitor cell populations was revealed more recently also in zebrafish, chick, and mouse. We reinvestigated the potency of the posterior plate in axolotl using grafts from transgenic embryos, immunohistochemistry, and in situ hybridization. The posterior plate is brachyury-positive except for its more anterior parts which express sox2. Between anterior and posterior regions of the posterior plate a small domain with sox2+ and bra+ cells exists. Lineage analysis of grafted GFP-labeled posterior plate tissue revealed that posterior GFP+ cells move from dorsal to ventral, form the posterior wall, turn anterior bilaterally, and join the gastrulated paraxial presomitic mesoderm. More anterior sox2+/GFP+ cells, however, are integrated into the developing spinal cord. Tail notochord is formed from axial mesoderm involuted already during gastrulation. Thus the posterior neural plate is a postgastrula source of paraxial mesoderm, which performs an anterior turn, a novel morphogenetic movement. More anterior plate cells, in contrast, do not turn anteriorly but become specified to form tail spinal cord.

  2. Posterior reversible encephalopathy syndrome associated with left horizontal gaze palsy

    PubMed Central

    Studyvin, Sarah; Al-Halawani, Moh’d; Amireh, Sawsan; Thawabi, Mohammad

    2017-01-01

    Posterior reversible encephalopathy syndrome (PRES) is characterized by rapid onset of symptoms including headache, seizures, altered consciousness, and visual disturbance, as well as radiologic findings of focal reversible vasogenic edema. Multiple visual disturbances have been described in PRES, such as hemianopia, visual neglect, auras, visual hallucinations, and cortical blindness. However, horizontal gaze palsy has not been previously reported. We report a 72-year-old female who presented with blurred vision, severe headache, lethargy, and later developed seizures. She was found to have left horizontal gaze palsy with intact vestibulo-ocular reflex. Brain magnetic resonance imaging (MRI) showed severe edema throughout the subcortical white matter, and signal in the posterior parietal and occipital lobes. She was diagnosed with PRES associated with supranuclear gaze palsy. PMID:28361069

  3. Transoral decompression and posterior stabilisation in Morquio's disease.

    PubMed Central

    Ashraf, J; Crockard, H A; Ransford, A O; Stevens, J M

    1991-01-01

    A 3.5 year old boy with Morquio's disease was referred with a persisting left hemiparesis four months after a fall and was found to have craniocervical junction compression due to atlantoaxial subluxation and significant anterior soft tissue compression. Transient unconsciousness at the time of the fall was probably due to medullary concussion as a result of hyperextension, not a head injury. Spinal cord compression due to atlantoaxial subluxation at the craniovertebral junction is a major cause of disability and death in these patients. Once cervical myelopathy appears, early posterior occipitocervical fusion has been advocated in order to arrest the progression of neurological disability and this is successful in most cases. This conventional approach was considered unsafe because of the significant anterior compression. A combined anterior transoral decompression with posterior fusion to deal with this particularly difficult problem is described. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:1755646

  4. [Macular threshold after ECCE and posterior chamber IOL implantation].

    PubMed

    Baltatzis, S; Georgopoulos, G; Andreanos, D

    1989-01-01

    In the present paper, the macular threshold after ECCE and posterior chamber intraocular lens implantation, was studied in an effort to determine the time period needed for full postoperative recovery of macular function. We evaluated 22 eyes in 20 patients who underwent extracapsular cataract extraction and posterior chamber IOL implantation. There were 12 men and 8 women between the ages of 40 and 62 years with mean age of 53 years. Postoperative visual field testing was performed within the central 4 degrees with an automated static perimeter (Humphrey Visual Field Analyser), using a macular threshold test pattern. It has been established that central retinal sensitivity in pseudophakia shows a postoperative decrease and consequently recovers to almost normal levels within one month. The exact cause of this reduction remains under discussion and further control mainly with fluorescein angiography is necessary.

  5. Clinical Characteristics of Posterior and Lateral Semicircular Canal Dehiscence

    PubMed Central

    Spasic, Marko; Trang, Andy; Chung, Lawrance K.; Ung, Nolan; Thill, Kimberly; Zarinkhou, Golmah; Gopen, Quinton S.; Yang, Isaac

    2015-01-01

    The objective of this study was to evaluate the characteristic symptoms of and treatments for lateral semicircular canal dehiscence (LSCD) and posterior semicircular canal dehiscence (PSCD) and its proposed mechanism. A dehiscence acquired in any of the semicircular canals may evoke various auditory symptoms (autophony and inner ear conductive hearing loss) or vestibular symptoms (vertigo, the Tullio phenomenon, and Hennebert sign) by creating a “third mobile window” in the bone that enables aberrant communication between the inner ear and nearby structures. A PubMed search was performed using the keywords lateral, posterior, and semicircular canal dehiscence to identify all relevant cases. Our data suggest that PSCD, although clinically rare, is most likely associated with a high-riding jugular bulb and fibrous dysplasia. Patients may experience auditory manifestations that range from mild conductive to extensive sensorineural hearing loss. LSCD is usually associated with chronic otitis media with cholesteatoma. PMID:26682120

  6. Posterior polymorphous dystrophy of the cornea. An ultrastructural study.

    PubMed

    de Felice, G P; Braidotti, P; Viale, G; Bergamini, F; Vinciguerra, P

    1985-01-01

    A corneal button excised from a 2-month-old infant with congenital posterior polymorphous dystrophy of the cornea, a rare disease affecting Descemet's membrane and endothelium, was examined by electron microscopy. We observed irregularly arranged, sometimes multilayered cells with marked epithelial features, lining the posterior surface of the cornea in place of the endothelium, and Descemet's membrane with focal alterations sometimes involving all of its layers. We interpreted these abnormal cells as epithelial-like cells. As these findings were in a very young patient, which is unusual, we concluded that the onset of the disease may take place in the early period of intrauterine life, corresponding to the beginning of Descemet's membrane production.

  7. Posterior Fixation Techniques in the Subaxial Cervical Spine

    PubMed Central

    Ghori, Ahmer; Makanji, Heeren; Cha, Thomas

    2015-01-01

    This article reviews the historical context, indications, techniques, and complications of four posterior fixation techniques to stabilize the subaxial cervical spine. Specifically, posterior wiring, laminar screw fixation, lateral mass fixation, and pedicle screw fixation are among the common methods of operative fixation of the subaxial cervical spine. While wiring and laminar screw fixation are now rarely used, both lateral mass and pedicle screw fixation are technically challenging and present the risk of significant complications if performed incorrectly. With a sound understanding of anatomy and rigorous preoperative evaluation of bony structures, both lateral mass and pedicle screw fixation provide a safe and reliable method for subaxial cervical spine fixation. PMID:26594602

  8. Posterior left atrial wall hematoma mimicking cystic intracavitary atrial mass.

    PubMed

    Bahnacy, Yasser; Suresh, Cheriyil; Dawoud, Hamed; Zubaid, Mohammad

    2010-10-01

    Atrial myxoma is the most common benign primary tumor of the heart most commonly in the left atrium (LA). Cystic or cavitated intracardiac masses are rare. We report the case of a 43-year-old male patient admitted with chest infection, hemoptysis, and severe respiratory distress, who had to be ventilated. Chest computed tomography showed bilateral lung consolidation with large mass occupying the region of the LA. Transthoracic echocardiography and transesophageal echocardiography showed a large intracavitary left atrial cystic mobile mass. Open-heart surgical exploration did not show any mass inside the LA. A posterior left atrial wall hematoma was found and evacuated. Biopsies confirmed the presence of blood clots. Posterior left atrial wall hematoma may appear as left atrial intracavitary cystic mass and should be included in the differential diagnosis of cystic left atrial mass.

  9. [Cysts in the posterior triangle of the neck in adults].

    PubMed

    Brea-Álvarez, Beatriz; Roldán-Hidalgo, Amaya

    2015-01-01

    Cystic lesions of the posterior triangle are a pathologic entity whose diagnosis is made in the first two years of life. Its presentation in adulthood is an incidental finding and the differential diagnosis includes cystic lymphangioma, lymphatic metastasis of thyroid cancer and branchial cyst. Often with the finding of a cervical lump, FNA is made before diagnostic imaging is performed, however, this procedure is not always advisable. We reviewed the cases of patients who came last year to our department with a cystic mass in this location and correlating the imaging findings with pathologic specimen. We show characteristic findings of these lesions in order to make an early diagnosis and thus to get the approach and treatment appropriate of adult patients with a cystic lesion in the posterior cervical triangle.

  10. Evaluation of arthroscopic treatment of posterior shoulder instability

    PubMed Central

    Garcia, José Carlos; Maia, Lucas Russo; Fonseca, Juliano Rocha; Zabeu, José Luís Amim; Garcia, Jesely Pereira Myrrha

    2015-01-01

    OBJECTIVE: To provide data for the analysis of arthroscopy as a method of surgical treatment for shoulder and discuss its actual indications and preliminary results. METHODS: We evaluated 15 patients submitted to reverse Bankart arthroscopic surgery. We used the UCLA (University of California at Los Angeles) score to measure the results before surgery and 12 months thereafter. RESULTS: The average UCLA score changed from 26.67±0.25 (SD 0.97) before surgery to 34.20±0.53 (SD 2.04) after surgery. The effectiveness of surgery was 93%. In five cases loose bodies were found. A patient undergoing remplissage was evaluated separately. The data did not change after 24 months post-surgery. CONCLUSION: The arthroscopic treatment of posterior shoulder instability and posterior dislocation of the shoulder has been proved feasible and results in our series followed the same trends as in the literature. Level of Evidence III, Transversal Retrospective Study. PMID:26207089

  11. Downregulation of the posterior medial frontal cortex prevents social conformity.

    PubMed

    Klucharev, Vasily; Munneke, Moniek A M; Smidts, Ale; Fernández, Guillén

    2011-08-17

    We often change our behavior to conform to real or imagined group pressure. Social influence on our behavior has been extensively studied in social psychology, but its neural mechanisms have remained largely unknown. Here we demonstrate that the transient downregulation of the posterior medial frontal cortex by theta-burst transcranial magnetic stimulation reduces conformity, as indicated by reduced conformal adjustments in line with group opinion. Both the extent and probability of conformal behavioral adjustments decreased significantly relative to a sham and a control stimulation over another brain area. The posterior part of the medial frontal cortex has previously been implicated in behavioral and attitudinal adjustments. Here, we provide the first interventional evidence of its critical role in social influence on human behavior.

  12. Management of noninfectious posterior uveitis with intravitreal drug therapy

    PubMed Central

    Tan, Hui Yi; Agarwal, Aniruddha; Lee, Cecilia S; Chhablani, Jay; Gupta, Vishali; Khatri, Manoj; Nirmal, Jayabalan; Pavesio, Carlos; Agrawal, Rupesh

    2016-01-01

    Uveitis is an important cause of vision loss worldwide due to its sight-threatening complications, especially cystoid macular edema, as well as choroidal neovascularization, macular ischemia, cataract, and glaucoma. Systemic corticosteroids are the mainstay of therapy for noninfectious posterior uveitis; however, various systemic side effects can occur. Intravitreal medication achieves a therapeutic level in the vitreous while minimizing systemic complications and is thus used as an exciting alternative. Corticosteroids, antivascular endothelial growth factors, immunomodulators such as methotrexate and sirolimus, and nonsteroidal anti-inflammatory drugs are currently available for intravitreal therapy. This article reviews the existing literature for efficacy and safety of these various options for intravitreal drug therapy for the management of noninfectious uveitis (mainly intermediate, posterior, and panuveitis). PMID:27789936

  13. Posterior sternoclavicular dislocations--a diagnosis easily missed.

    PubMed Central

    Thomas, D. P.; Davies, A.; Hoddinott, H. C.

    1999-01-01

    Posterior dislocation of the sternoclavicular joint is a relatively rare injury and can be difficult to diagnose acutely. We report 3 cases of posterior dislocation of the sternoclavicular joint who presented to the Accident & Emergency Department within a 3 month period. All 3 patients had sustained a significant injury to the shoulder region and complained of pain around the medial clavicle. Two patients had also complained of dysphagia following the injury. Plain X-rays of the shoulder and chest were reported as normal by junior and senior medical staff. The diagnosis was delayed until CT scans were performed, and once this was established, open reduction and stabilisation was performed. Images Figure 1 Figure 2 Figure 3 p204-a PMID:10364956

  14. Absence of Posterior Triangle: Clinical and Embryological Perspective

    PubMed Central

    Singh, Shikha; Loh, Hitendra Kumar; Mehta, Vandana; Suri, Rajesh Kumar

    2017-01-01

    Sternocleidomastoid (SCM) and Trapezius (TM) muscle present in the cervical region serves as an important landmark in forming boundaries of posterior triangle of neck. This case reports a continuous muscle sheet obscuring the left posterior triangle in the neck of a 60-year-old Indian male cadaver. An unfamiliar oval gap was observed in its posterosuperior portion. Description of such a variant in anatomical literature is rare and is scarcely reported. An attempt has been made to portray its embryological and phylogenetic basis. In addition authors have endeavoured to discuss its clinical implications. Awareness of such anatomical variations is relevant for the operating surgeons in their endeavour to perform various reconstruction surgeries of head and neck, radiologists while concluding various levels in Computed Tomography (CT) and Magnetic Resonance Images (MRI) of the region and to the anaesthetists in their search for nerves and vessels while attempting various anaesthetic procedures. PMID:28384846

  15. Lumbo-costo-vertebral syndrome with posterior spinal dysraphism.

    PubMed

    Kumar, G Samson Sujit; Kulkarni, Vaijayantee; Haran, R P

    2005-09-01

    Lumbo-costo-vertebral syndrome, which includes abnormalities of the vertebral bodies, ribs and trunk musculature, is very rare and only few cases have been reported. We report a case of 18-month-old female child with absent ribs, hemivertebrae, superior lumbar hernia (features of lumbo-costo-vertebral syndrome) and posterior spinal dysraphism, which to our knowledge is the first case in the English literature with such a combination of defects. Embryology and management of the case is discussed.

  16. Detachments of the retinal pigment epithelium at the posterior pole.

    PubMed

    Noble, K G; Levitzky, M J; Carr, R E

    1976-08-01

    Multiple vitelliform cysts of the retina, a disorder of unknown cause in which there are multiple detachments of the retinal pigment epithelium at the posterior pole, occurred in five patients. In four patients all lesions were located outside the parafoveal area while one patient showed bilateral foveal elevations associated with more eccentric detachments. Several patients showed slow resolution of some of the detachments with mild disturbances of the pigment epithelium.

  17. Stenting for a symptomatic posterior cerebral artery stenosis.

    PubMed

    Xu, Gelin; Zheng, Ling; Zhou, Zhiming; Liu, Xinfeng

    2009-05-01

    Evolvement of endovascular devices and increase of operator expertise have made angioplasty and stenting in intracranial vessels technically possible. Stenting has been reported in treating stenosis in middle and anterior cerebral arteries with favorable outcomes. However, the feasibility of stenting for stenosis in posterior cerebral artery (PCA) has not been established. We report a patient with progressive focal cerebral ischemic symptoms, which were arrested after reconstruction of the associated PCA stenosis with stenting.

  18. Classical caesarean section through the posterior uterine wall.

    PubMed

    Bolaji, I I; Rafla, N M; Mylotte, M J

    1992-02-01

    We report a case of myomectomy and classical caesarean section through the posterior uterine wall necessitated by 180 degrees dextro-rotation of a gravid uterus with large fibroids. The non-specific clinical course and rarity of pathological torsion of the gravid uterus makes the preoperative diagnosis difficult. Ultrasound recognition antenatally of a fibroid changing its position should help with the prediction preoperatively of uterine rotation.

  19. Cadherin-mediated adhesion regulates posterior body formation

    PubMed Central

    Harrington, Michael J; Hong, Elim; Fasanmi, Oluwafoyinsa; Brewster, Rachel

    2007-01-01

    Background The anterior-posterior axis of the vertebrate embryo undergoes a dramatic elongation during early development. Convergence and extension of the mesoderm, occurring during gastrulation, initiates the narrowing and lengthening of the embryo. However the lengthening of the axis continues during post-gastrula stages in the tailbud region, and is thought to involve convergent extension movements as well as other cell behaviors specific to posterior regions. Results We demonstrate here, using a semi-dominant N-cadherin allele, that members of the classical cadherin subfamily of cell-cell adhesion molecules are required for tailbud elongation in the zebrafish. In vivo imaging of cell behaviors suggests that the extension of posterior axial mesodermal cells is impaired in embryos that carry the semi-dominant N-cadherin allele. This defect most likely results from a general loss of cell-cell adhesion in the tailbud region. Consistent with these observations, N-cadherin is expressed throughout the tailbud during post-gastrulation stages. In addition, we show that N-cadherin interacts synergistically with vang-like 2, a member of the non-canonical Wnt signaling/planar cell polarity pathway, to mediate tail morphogenesis. Conclusion We provide the first evidence here that N-cadherin and other members of the classical cadherin subfamily function in parallel with the planar cell polarity pathway to shape the posterior axis during post-gastrulation stages. These findings further highlight the central role that adhesion molecules play in the cellular rearrangements that drive morphogenesis in vertebrates and identify classical cadherins as major contributors to tail development. PMID:18045497

  20. Trigeminal autonomic cephalgia caused by recurrent posterior scleritis.

    PubMed

    Alim-Marvasti, Ali; Ho, Jason; Weatherall, Mark; Patel, Maneesh; George, Sheena; Viegas, Stuart

    2016-12-01

    A 40-year-old woman presented with a side-locked headache with autonomic features, which then switched sides before reverting to the original side. The atypical features of side swapping, partial response to indometacin and abnormal optic disc appearances ultimately led to a diagnosis of recurrent posterior scleritis. We discuss the differential diagnosis of trigeminal autonomic cephalgias and its secondary causes, and provide practical pointers for its investigation and management.