Science.gov

Sample records for nerve sheath decompression

  1. Diagnosis of optic nerve sheath meningioma during optic nerve sheath decompression.

    PubMed

    Meeker, Austin R; Ko, Melissa W; Carruth, Bryant P; Strumpf, Kenneth B; Bersani, Thomas A

    2017-02-01

    Optic nerve sheath meningioma (ONSM) is typically diagnosed based on clinical suspicion and imaging characteristics and is most often treated with radiation. Historically, biopsy, optic nerve sheath decompression, and debulking surgeries have been avoided for fear of optic nerve vascular disruption and tumor spread into the orbit. This is a case of a 48-year-old man who presented with unilateral optic disc edema, declining visual acuity, and a visual field defect. Despite an initial improvement with acetazolamide, his vision subsequently worsened. With an elevated lumbar puncture opening pressure and imaging showing right optic nerve sheath enhancement, the differential diagnosis included ONSM, perineuritis and idiopathic intracranial hypertension (IIH). Optic nerve sheath decompression (ONSD) with biopsy was performed, simultaneously decompressing the nerve and yielding a sample for pathologic analysis. A pathologic diagnosis of ONSM was made and treatment with radiation was subsequently initiated, but vision began to improve after the surgical decompression alone.

  2. Optic Nerve Decompression

    MedlinePlus

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

  3. Optic Nerve Sheath Meningiomas.

    PubMed

    Radhakrishnan, Sunita; Lee, Michael S

    2005-01-01

    Optic nerve sheath meningiomas (ONSMs) grow slowly and, if untreated, patients may have stable visual function for up to several years. Treatment of an ONSM may lead to vision loss (radiation retinopathy or optic neuropathy). Therefore, observation is recommended for a patient with ONSM and relatively preserved visual acuity, color vision, pupils, and visual fields. Follow-up every 4 to 6 months initially is recommended extending to annual examinations if visual function and tumor size remain stable for a few years. Neuroimaging can be repeated every 12 months. An undisputed decline in visual function or any intracranial extension warrants treatment of the ONSM. The treatment of choice for a tumor confined to the orbit is stereotactic fractionated radiation. Stereotactic fractionated radiation uses multiple small doses of radiation using tight margins. A reasonable alternative, three-dimensional conformal fractionated radiation uses computed tomography-guided planning but usually requires wider margins. Conventional radiation uses much wider margins and would not be recommended for treatment of ONSM. The radiation can be administered during 5 to 6 weeks in 28 daily fractions of 1.8 to 2 Gy/fraction to a total of 50.4 to 56 Gy. Many patients have improvement or stabilization of their visual function. Gamma knife radiosurgery does not have a role in ONSM because the required dose is toxic to the optic nerve. A tumor that extends intracranially may be treated with fractionated radiation if any vision remains. Surgical excision can be considered for significant intracranial extension but this often leads to complete vision loss in the ipsilateral eye. A blind, disfigured eye also may be treated with en bloc surgical resection of the meningioma.

  4. Optic nerve decompression in osteopetrosis.

    PubMed

    Al-Mefty, O; Fox, J L; Al-Rodhan, N; Dew, J H

    1988-01-01

    Osteopetrosis is a rare disorder characterized by generalized increased skeletal density with abnormalities of bone modeling. The skull base is usually involved. Loss of vision with optic nerve atrophy is the most common neurological finding and is traditionally believed to be the result of optic nerve compression within the compromised optic canal. However, retinal degeneration has recently been described and is hypothesized to be the etiology of the visual loss (thus challenging the value of surgical decompression). The authors report their experience with six children suffering from osteopetrosis and severe visual loss. All six patients underwent bilateral microsurgical optic nerve decompression through a supraorbital craniotomy. Improvement in visual acuity occurred postoperatively in five patients, and none had complications. Two technical points are emphasized: 1) optic nerve decompression should be wide and include not only unroofing of the canal but also drilling along both sides of the optic nerve, and 2) the thick, irregular, and highly domed orbital roof should be smoothed down by high-speed drilling to facilitate surgical exposure with minimal retraction of the frontal lobe.

  5. Verification of nerve decompression using mechanomyography.

    PubMed

    Wessell, Nolan; Khalil, Jad; Zavatsky, Joseph; Ghacham, Wael; Bartol, Stephen

    2016-06-01

    Assessment of nerve root decompression in surgery is largely based on visualization and tactile feedback. Often times, visualization can be limited, such as in minimally invasive surgery, and tactile feedback is a subjective assessment that makes the evaluation of successful nerve decompression difficult. Electromyography (EMG) has been proposed as an assessment tool, but EMG responses are often difficult to quantify. Alternatively, mechanomyography (MMG) provides a quantifiable response with high signal-to-noise ratio compared with EMG. MMG provides a sensitive tool to accurately quantify mechanical responses to motor action potentials generated by electrical stimulus, allowing more reliable assessment of nerve decompression. The aim of this study was to assess the ability of MMG to quantitatively demonstrate successful nerve root decompression. Prospective cohort, Therapeutic Level III, Urban Level I Trauma Center. A total of 46 patients (72 affected nerve roots) undergoing decompression procedures for lower extremity radiculopathy caused by nerve root compression were enrolled in the study. The study population included 15 patients with herniated nucleus pulposus (HNP) and 31 with lateral recess stenosis (LRS). Visual analog scale (VAS) score. A total of 72 nerves roots in 46 patients undergoing lumbar decompression procedures, for lower extremity radicular symptoms, were tested using MMG. Nerves were stimulated upstream from the compression site, and the lowest threshold current needed to generate a muscle response was determined. Signal response sizes were recorded before and after decompression. VAS scores were collected pre- and postoperatively. Of the patients, 90% (65/72) had elevated stimulation thresholds (>1 milliamp [mA]) before decompression. After decompression, 98% of patients (64/65) with elevated current thresholds exhibited a drop in threshold of ≥1 mA (p<.001). A postdecompression increase in response amplitude was recorded in all patients

  6. Intrasellar malignant peripheral nerve sheath tumor (MPNST).

    PubMed

    Krayenbühl, N; Heppner, F; Yonekawa, Y; Bernays, R L

    2007-02-01

    Intracranial malignant peripheral nerve sheath tumors (MPNST) and intrasellar schwannomas are rare tumors. We describe a case of an intrasellar schwannoma with progression to a MPNST, a finding that, although very rare, extends the differential diagnosis of intrasellar lesions.

  7. Malignant Peripheral Nerve Sheath Tumors.

    PubMed

    Durbin, Adam D; Ki, Dong Hyuk; He, Shuning; Look, A Thomas

    2016-01-01

    Malignant peripheral nerve sheath tumors (MPNST) are tumors derived from Schwann cells or Schwann cell precursors. Although rare overall, the incidence of MPNST has increased with improved clinical management of patients with the neurofibromatosis type 1 (NF1) tumor predisposition syndrome. Unfortunately, current treatment modalities for MPNST are limited, with no targeted therapies available and poor efficacy of conventional radiation and chemotherapeutic regimens. Many murine and zebrafish models of MPNST have been developed, which have helped to elucidate the genes and pathways that are dysregulated in MPNST tumorigenesis, including the p53, and the RB1, PI3K-Akt-mTOR, RAS-ERK and Wnt signaling pathways. Preclinical results have suggested that new therapies, including mTOR and ERK inhibitors, may synergize with conventional chemotherapy in human tumors. The discovery of new genome editing technologies, like CRISPR-cas9, and their successful application to the zebrafish model will enable rapid progress in the faithful modeling of MPNST molecular pathogenesis. The zebrafish model is especially suited for high throughput screening of new targeted therapeutics as well as drugs approved for other purposes, which may help to bring enhanced treatment modalities into human clinical trials for this devastating disease.

  8. Dural ectasia of the optic nerve sheath

    PubMed Central

    Kacem, Hanane Hadj; Hammani, Lehcen; Ajana, Ali; Nassar, Itimad

    2014-01-01

    Optic nerve dural ectasia is a rare cause of optic nerve sheath enlargement due to the accumulation of CSF around the optic nerve with no associated pathology. It diagnosed by MRI studies and can follow benign or sometimes an unfavorable course. We describe the case of a 24-day-old female referred for a visual blurring, which we diagnosed as a dural ectasia of the optic nerve sheath by MRI and confirmed in surgical intervention. We present this case report to illustrate the classic imaging features of the disease. PMID:25374645

  9. Delayed facial nerve decompression for Bell's palsy.

    PubMed

    Kim, Sang Hoon; Jung, Junyang; Lee, Jong Ha; Byun, Jae Yong; Park, Moon Suh; Yeo, Seung Geun

    2016-07-01

    Incomplete recovery of facial motor function continues to be long-term sequelae in some patients with Bell's palsy. The purpose of this study was to investigate the efficacy of transmastoid facial nerve decompression after steroid and antiviral treatment in patients with late stage Bell's palsy. Twelve patients underwent surgical decompression for Bell's palsy 21-70 days after onset, whereas 22 patients were followed up after steroid and antiviral therapy without decompression. Surgical criteria included greater than 90 % degeneration on electroneuronography and no voluntary electromyography potentials. This study was a retrospective study of electrodiagnostic data and medical chart review between 2006 and 2013. Recovery from facial palsy was assessed using the House-Brackmann grading system. Final recovery rate did not differ significantly in the two groups; however, all patients in the decompression group recovered to at least House-Brackmann grade III at final follow-up. Although postoperative hearing threshold was increased in both groups, there was no significant between group difference in hearing threshold. Transmastoid decompression of the facial nerve in patients with severe late stage Bell's palsy at risk for a poor facial nerve outcome reduced severe complications of facial palsy with minimal morbidity.

  10. Optic Nerve Sheath Mechanics in VIIP Syndrome

    NASA Technical Reports Server (NTRS)

    Raykin, Julia; Feola, Andrew; Gleason, Rudy; Mulugeta, Lealem; Myers, Jerry; Nelson, Emily; Samuels, Brian; Ethier, C. Ross

    2015-01-01

    Visual Impairment and Intracranial Pressure (VIIP) syndrome results in a loss of visual function and occurs in astronauts following long-duration spaceflight. Understanding the mechanisms that lead to the ocular changes involved in VIIP is of critical importance for space medicine research. Although the exact mechanisms of VIIP are not yet known, it is hypothesized that microgravity-induced increases in intracranial pressures (ICP) drive the remodeling of the optic nerve sheath, leading to compression of the optic nerve which in turn may reduce visual acuity. Some astronauts present with a kink in the optic nerve after return to earth, suggesting that tissue remodeling in response to ICP increases may be taking place. The goal of this work is to characterize the mechanical properties of the optic nerve sheath (dura mater) to better understand its biomechanical response to increased ICP.

  11. Endoscopic Optic Nerve Decompression Through Supraorbital Keyhole Extradural Approach: A Cadaveric Study.

    PubMed

    Wang, Xiaodong; Wu, Wei; Zhang, Hengzhu; Lan, Qing

    2017-01-01

    Many approaches for optic nerve decompression have their own advantages and disadvantages. The aim of this study was to perform endoscopic decompression of optic nerve through the supraorbital keyhole and evaluate its feasibility. Ten adult cadaveric heads were studied using 4-mm, 0- and 30-degree rigid endoscopes to perform the optic nerve decompression through the supraorbital keyhole extradural approach. Furthermore, the relevant measurements about the optic canal were recorded. Through the supraorbital keyhole, the endoscope was introduced into the extradural space, and the following structures could be exposed and identified: the sphenoid ridge, the anterior clinoid process, the roof of the optic canal and the falciform ligament. The roof and lateral wall of the optic canal were removed using a drill under the endoscope, and more sufficient decompression could be achieved by further incising the falciform ligament and optic sheath. After measurement, the distance from the zygomatic process of the frontal bone to the optic canal was 59.32 ± 2.27 mm, the distance from the upper midpoint of the posterior foramen of the optic canal to the internal carotid artery was 3.80 ± 0.93 mm. According to the cadaveric study, it is feasible to perform the endoscopic decompression of optic nerve with a clear view through the supraorbital keyhole extradural approach. Our study may provide a minimally invasive and safe option for the optic nerve decompression.

  12. Optic Nerve Sheath Mechanics in VIIP Syndrome

    NASA Technical Reports Server (NTRS)

    Raykin, Julia; Forte, Taylor E.; Wang, Roy; Feola, Andrew; Samuels, Brian; Myers, Jerry; Nelson, Emily; Gleason, Rudy; Ethier, C. Ross

    2016-01-01

    Visual Impairment Intracranial Pressure (VIIP) syndrome is a major concern in current space medicine research. While the exact pathology of VIIP is not yet known, it is hypothesized that the microgravity-induced cephalad fluid shift increases intracranial pressure (ICP) and drives remodeling of the optic nerve sheath. To investigate this possibility, we are culturing optic nerve sheath dura mater samples under different pressures and investigating changes in tissue composition. To interpret results from this work, it is essential to first understand the biomechanical response of the optic nerve sheath dura mater to loading. Here, we investigated the effects of mechanical loading on the porcine optic nerve sheath.Porcine optic nerves (number: 6) were obtained immediately after death from a local abattoir. The optic nerve sheath (dura mater) was isolated from the optic nerve proper, leaving a hollow cylinder of connective tissue that was used for biomechanical characterization. We developed a custom mechanical testing system that allowed for unconfined lengthening, twisting, and circumferential distension of the dura mater during inflation and under fixed axial loading. To determine the effects of variations in ICP, the sample was inflated (0-60 millimeters Hg) and circumferential distension was simultaneously recorded. These tests were performed under variable axial loads (0.6 grams - 5.6 grams at increments of 1 gram) by attaching different weights to one end of the dura mater. Results and Conclusions: The samples demonstrated nonlinear behavior, similar to other soft connective tissue (Figure 1). Large increases in diameter were observed at lower transmural pressures (approximately 0 to 5 millimeters Hg), whereas only small diameter changes were observed at higher pressures. Particularly interesting was the existence of a cross-over point at a pressure of approximately 11 millimeters Hg. At this pressure, the same diameter is obtained for all axial loads applied

  13. ULTRASTRUCTURE OF THE PRAWN NERVE SHEATHS

    PubMed Central

    Doggenweiler, C. F.; Heuser, John E.

    1967-01-01

    The sheaths from freshly teased nerve fibers of the prawn exhibit a positive radial birefringence, consistent with their EM appearance as highly organized laminated structures composed of numerous thin cytoplasmic sheets or laminae bordered by unit membranes and arranged concentrically around the axon. The closely apposed membranes in these sheaths are fragile and often break down into rows of vesicles during fixation. Desmosome-like attachment zones occur in many regions of the sheath. The membranes within these zones resist vesiculation and thereby provide a "control" region for relating the type of vesicles formed in the fragile portions of the sheaths to the specific fixation conditions. It is proposed that during fixation the production of artifactual vesicles is governed by an interplay of three factors: (a) direct chemical action of the fixative on the polar strata of adjacent unit membranes, (b) osmotic forces applied to membranes during fixation, and (c) the pre-existing natural relations between adjacent membranes. It is found that permanganate best preserves the continuity of the membranes but will still produce vesicles if the fixative exerts severe osmotic forces. These results support other reports (19) of the importance of comparing tissues fixed by complementary procedures so that systematic artifacts will not be described as characteristic of the natural state. PMID:4166578

  14. Nerve Sheath Myxoma: Report of A Rare Case

    PubMed Central

    Bhat, Amoolya; C, Vijaya; VK, Sundeep

    2015-01-01

    Nerve sheath myxoma defined by Harkin and Reed is an uncommon benign neoplasm with nerve sheath like features. It has several cytological and histological differential diagnoses. One such lesion is neurothekeoma, which can be differentiated using immunohistochemistry. In most of the previous reports nerve sheath myxoma and neurothekeoma were considered synonymous and were often confused for one another. This case report separates the two using immunohistochemistry. Also, the cytological features of nerve sheath myxoma are not well documented in the past. This case report attempts to display the cyto-morphology of nerve sheath myxoma. We report a rare case of nerve sheath myxoma diagnosed on cytological features confirmed by histopathology and immunohistochemistry in a 32-year-old lady who presented with an asymptomatic nodule over the left cervical area and discuss its cyto-histological mimics. PMID:26023558

  15. Nerve sheath myxoma: report of a rare case.

    PubMed

    Bhat, Amoolya; Narasimha, Apaparna; C, Vijaya; Vk, Sundeep

    2015-04-01

    Nerve sheath myxoma defined by Harkin and Reed is an uncommon benign neoplasm with nerve sheath like features. It has several cytological and histological differential diagnoses. One such lesion is neurothekeoma, which can be differentiated using immunohistochemistry. In most of the previous reports nerve sheath myxoma and neurothekeoma were considered synonymous and were often confused for one another. This case report separates the two using immunohistochemistry. Also, the cytological features of nerve sheath myxoma are not well documented in the past. This case report attempts to display the cyto-morphology of nerve sheath myxoma. We report a rare case of nerve sheath myxoma diagnosed on cytological features confirmed by histopathology and immunohistochemistry in a 32-year-old lady who presented with an asymptomatic nodule over the left cervical area and discuss its cyto-histological mimics.

  16. Optic Nerve Decompression through a Supraorbital Approach

    PubMed Central

    Rigante, Luigi; Evins, Alexander I.; Berra, Luigi V.; Beer-Furlan, André; Stieg, Philip E.; Bernardo, Antonio

    2015-01-01

    Objective We propose a stepwise decompression of the optic nerve (ON) through a supraorbital minicraniotomy and describe the surgical anatomy of the ON as seen through this approach. We also discuss the clinical applications of this approach. Methods Supraorbital approaches were performed on 10 preserved cadaveric heads (20 sides). First, 3.5-cm skin incisions were made along the supraciliary arch from the medial third of the orbit and extended laterally. A 2 × 3-cm bone flap was fashioned and extradural dissections were completed. A 180-degree unroofing of the ON was achieved, and the length and width of the proximal and distal portions of the optic canal (OC) were measured. Results The supraorbital minicraniotomy allowed for identification of the anterior clinoid process and other surgical landmarks and adequate drilling of the roof of the OC with a comfortable working angle. A 25-degree contralateral head rotation facilitated visualization of the ON. Conclusion The supraorbital approach is a minimally invasive and cosmetically favorable alternative to more extended approaches with longer operative times used for the management of ON decompression in posttraumatic or compressive optic neuropathy from skull base pathologies extending into the OC. The relative ease of this approach provides a relatively short learning curve for developing neurosurgeons. PMID:26225308

  17. Optic Nerve Decompression through a Supraorbital Approach.

    PubMed

    Rigante, Luigi; Evins, Alexander I; Berra, Luigi V; Beer-Furlan, André; Stieg, Philip E; Bernardo, Antonio

    2015-06-01

    Objective We propose a stepwise decompression of the optic nerve (ON) through a supraorbital minicraniotomy and describe the surgical anatomy of the ON as seen through this approach. We also discuss the clinical applications of this approach. Methods Supraorbital approaches were performed on 10 preserved cadaveric heads (20 sides). First, 3.5-cm skin incisions were made along the supraciliary arch from the medial third of the orbit and extended laterally. A 2 × 3-cm bone flap was fashioned and extradural dissections were completed. A 180-degree unroofing of the ON was achieved, and the length and width of the proximal and distal portions of the optic canal (OC) were measured. Results The supraorbital minicraniotomy allowed for identification of the anterior clinoid process and other surgical landmarks and adequate drilling of the roof of the OC with a comfortable working angle. A 25-degree contralateral head rotation facilitated visualization of the ON. Conclusion The supraorbital approach is a minimally invasive and cosmetically favorable alternative to more extended approaches with longer operative times used for the management of ON decompression in posttraumatic or compressive optic neuropathy from skull base pathologies extending into the OC. The relative ease of this approach provides a relatively short learning curve for developing neurosurgeons.

  18. Malignant peripheral nerve sheath tumour of penis.

    PubMed

    Kaur, J; Madan, R; Singh, L; Sharma, D N; Julka, P K; Rath, G K; Roy, S

    2015-04-01

    Malignant peripheral nerve sheath tumour (MPNST) is a rare variety of soft tissue sarcoma that originates from Schwann cells or pluripotent cells of neural crest origin. They have historically been difficult tumours to diagnose and treat. Surgery is the mainstay of treatment with a goal to achieve negative margins. Despite aggressive surgery and adjuvant therapy, the prognosis of patients with MPNST remains poor. MPNST arising from penis is a very rare entity; thus, it presents a diagnostic and therapeutic challenge. We present a case of penile MPNST in a 38-year-old man in the absence of neurofibromatosis treated with surgery followed by post-operative radiotherapy to a dose of 60 Gray in 30 fractions and adjuvant chemotherapy with ifosfamide and adriamycin.

  19. Radiation-induced malignant and atypical peripheral nerve sheath tumors

    SciTech Connect

    Foley, K.M.; Woodruff, J.M.; Ellis, F.T.; Posner, J.B.

    1980-04-01

    The reported peripheral nerve complications of therapeutic irradiation in humans include brachial and lumbar plexus fibrosis and cranial and peripheral nerve atrophy. We have encountered 9 patients with malignant (7) and atypical (2) peripheral nerve tumors occurring in an irradiated site suggesting that such tumors represent another delayed effect of radiation treatment on peripheral nerve. In all instances the radio-theray was within an acceptable radiation dosage, yet 3 patients developed local radiation-induced skin and bony abnormalities. The malignant peripheral nerve sheath tumors developed only in the radiation port. Animal studies support the clinical observation that malignant peripheral nerve sheath tumors can occur as a delayed effect of irradiation.

  20. Melanocytic Malignant Peripheral Nerve Sheath Tumor of the Male Breast.

    PubMed

    Wang, Haijun; Ge, Jing; Chen, Lirong; Xie, Panpan; Chen, Fangfang; Chen, Yiding

    2009-01-01

    SUMMARY: BACKGROUND: Malignant peripheral nerve sheath tumors are rare tumor entities that originate from peripheral nerve sheaths and have an unfavorable prognosis. Common sites include deeper soft tissues, usually in the proximity of a nerve trunk. Breast is an absolutely rare location of this lesion, and presentation as a breast lump in the male breast is even rarer. CASE REPORT: A 65-year-old man presented with a 6-month history of a painless mass of the left breast. Tissue biopsy was performed. Histopathology revealed a malignant spindle cell tumor which was confirmed to be a melanocytic malignant peripheral nerve sheath tumor on the basis of immunopositivity for HMB45 and S-100. CONCLUSION: There are no generally accepted guidelines for the treatment of malignant peripheral nerve sheath tumors in the male breast. The patient was referred for radiation therapy after simple mastectomy.

  1. Synovial sarcoma mimicking benign peripheral nerve sheath tumor.

    PubMed

    Larque, Ana B; Bredella, Miriam A; Nielsen, G Petur; Chebib, Ivan

    2017-07-08

    To assess the radiographic and clinicopathologic features of synovial sarcoma of the nerve that were clinically or radiologically interpreted as benign peripheral nerve sheath tumor. Five patients with synovial sarcoma arising from the peripheral nerve and interpreted clinically and radiologically as peripheral nerve sheath tumors were identified. Clinicopathologic and imaging features were evaluated. There were three females and two males, ranging in age from 28 to 50 (mean 35.8) years. Most patients (4/5) complained of a mass, discomfort or pain. MR images demonstrated a heterogeneous, enhancing, soft tissue mass contiguous with the neurovascular bundle. On histologic examination, most tumors were monophasic synovial sarcoma (4/5). At the time of surgery, all tumors were noted to arise along or within a peripheral nerve. All patients were alive with no evidence of disease with median follow-up of 44 (range 32-237) months. For comparison, approximately 775 benign peripheral nerve sheath tumors of the extremities were identified during the same time period. Primary synovial sarcoma of the nerve can mimic peripheral nerve sheath tumors clinically and on imaging and should be included in the differential diagnosis for tumors arising from peripheral nerves.

  2. Malignant peripheral nerve sheath tumour presenting with Horner's syndrome.

    PubMed

    Basuthakur, Sumitra; Sengupta, Amitava; Bandyopadhyay, Ankan; Banerjee, Arpita

    2013-09-01

    A young male presented with clinical and radiological features of right apical lung mass and Horner's syndrome. Subsequently the patient was diagnosed as a case of malignant peripheral nerve sheath tumour (MPNST) at the apex of right lung originating from an intercostal nerve and compressing ipsilateral cervical sympathetic plexus and lower cord of brachial plexus, in a case of neurofibromatosis type 1.

  3. Endoscopic decompression for intraforaminal and extraforaminal nerve root compression

    PubMed Central

    2011-01-01

    Objective The purpose of this study was to evaluate the outcome of endoscopic decompression surgery for intraforaminal and extraforaminal nerve root compression in the lumbar spine. Methods The records from seventeen consecutive patients treated with endoscopic posterior decompression without fusion for intaforaminal and extraforaminal nerve root compression in the lumbar spine (7 males and 10 females, mean age: 67.9 ± 10.7 years) were retrospectively reviewed. The surgical procedures consisted of lateral or translaminal decompression with or without discectomy. The following items were investigated: 1) the preoperative clinical findings; 2) the radiologic findings including MRI and computed tomography-discography; and 3) the surgical outcome as evaluated using the Japanese Orthopaedic Association scale for lower back pain (JOA score). Results All patients had neurological findings compatible with a radiculopathy, such as muscle weakness and sensory disturbance. MRI demonstrated the obliteration of the normal increased signal intensity fat in the intervertebral foramen. Ten patients out of 14 who underwent computed tomography-discography exhibited disc protrusion or herniation. Selective nerve root block was effective in all patients. During surgery, 12 patients were found to have a protruded disc or herniation that compressed the nerve root. Sixteen patients reported pain relief immediately after surgery. Conclusions Intraforaminal and extraforaminal nerve root compression is a rare but distinct pathological condition causing severe radiculopathy. Endoscopic decompression surgery is considered to be an appropriate and less invasive surgical option. PMID:21439083

  4. Hemimasticatory spasm treated with microvascular decompression of the trigeminal nerve.

    PubMed

    Chon, Kyu-Hyon; Lee, Jong-Myong; Koh, Eun-Jeong; Choi, Ha-Young

    2012-09-01

    Hemimasticatory spasm is a very rare disorder of the trigeminal nerve characterized by paroxysmal involuntary contraction of the jaw-closing muscles. The mechanisms leading to hemimasticatory spasm are still unclear. Recently, injection of botulinum toxin has become the treatment of choice due to its excellent results. We report a case of a successful treatment of hemimasticatory spasm via microvascular decompression of the motor branch of the trigeminal nerve.

  5. [Transformation of trigeminal nerve tumor into malignant peripheral nerve sheath tumor (MPNST)].

    PubMed

    Nenashev, E A; Cherekaev, V A; Kadasheva, A B; Kozlov, A V; Rotin, D L; Stepanian, M A

    2012-01-01

    Malignant peripheral nerve sheath tumor (MPNST) is a rare entity with only 18 cases of trigeminal nerve MPNST described by now and only one report of malignant transformation of trigeminal nerve tumor into MPNST published up to date. One more case of malignant transformation of trigeminal nerve (1st division) tumor into MPNST is demonstrated.

  6. Intraoperative Nerve Monitoring During Nerve Decompression Surgery in the Lower Extremity.

    PubMed

    Anderson, James C; Yamasaki, Dwayne S

    2016-04-01

    This article describes the benefits of intraoperative neurophysiologic monitoring (IONM) and proposes methods for integration into nerve decompression procedures. Standard procedures for intraoperative nerve monitoring (IONM) are illustrated as they would apply to the 3 nerve tunnels that have significant motor components within the lower extremity. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Peripheral Nerve Sheath Tumor of the Vagus Nerve in a Dog.

    PubMed

    Yap, Fui; Pratschke, Kathryn

    2016-01-01

    A peripheral nerve sheath tumor was diagnosed in a female, neutered Labrador retriever with a 6 mo history of coughing, retching, ptyalism, and left-sided Horner's syndrome. Computed tomography scan of the neck revealed a mass lesion between the carotid artery and esophagus in the mid-cervical region. Exploratory surgery was performed and an 18 cm section of thickened vagus nerve was excised. Histopathological findings and immunochemistry staining confirmed a malignant peripheral nerve sheath tumor. The tumor showed microscopic signs of malignancy, but there were no macroscopic signs of local extension or distant metastasis. This report documents a peripheral nerve sheath tumor of rare origin in dogs.

  8. Ulna Nerve Decompression at the Elbow in Patients with Normal Nerve Conduction Tests.

    PubMed

    Roberts, Gareth L; Maclean, Angus D; Logan, Andrew J

    2015-01-01

    Ulna nerve compression at the elbow is the second most common neuropathy of the upper limb. It has been suggested that nerve conduction tests are required to correctly make the diagnosis. The aim of this study was to assess whether patients with normal nerve conduction testing benefitted from surgical release of the ulna nerve. 56 patients with symptoms of ulna nerve compression at the elbow were evaluated prospectively. All patients underwent electrophysiology testing followed by ulna nerve decompression irrespective of the results of the electrophysiology testing. Functional scores using the QuickDASH and PEM score were collected up to 12 months post-surgery. No difference was found between the group with normal and the group with abnormal electrophysiology studies. We conclude that patients who clinically have ulna nerve compression still benefit from ulna nerve decompression despite normal nerve conduction tests.

  9. Malignant Peripheral Nerve Sheath Tumor -A Rare Malignancy in Mandible

    PubMed Central

    Majumdar, Sumit; Kotina, Sreekanth; Uppala, Divya; Kumar, Singam Praveen

    2016-01-01

    Malignant Peripheral Nerve Sheath Tumor (MPNST) is biologically an aggressive tumor that is usually found in the extremities, trunk and infrequently found in the head and neck area particularly in the jaws, arising from the cells allied with nerve sheath. Mandibular MPNST may either arise from a preexisting neurofibroma or develop de novo. Because of the greater variability from case to case in overall appearance both clinically and histologically, a case of MPNST of the mandible in a 25-year-old female patient is reported. The lesion was excised and immunohistological studies (S-100 & Neuron specific enolase) were conducted to confirm the neural origin. PMID:27504425

  10. Patients' perceptions of carpal tunnel and ulnar nerve decompression surgery.

    PubMed

    Khu, Kathleen Joy; Bernstein, Mark; Midha, Rajiv

    2011-03-01

    Carpal tunnel syndrome and ulnar nerve entrapment at the elbow are the most common entrapment neuropathies seen in adults. Surgery for nerve decompression is a safe and effective treatment option, and is usually performed under local anesthesia and as an outpatient procedure. This study aimed to explore patients' satisfaction and other aspects of the overall experience with this type of surgery. Qualitative research methodology was used. Semi-structured, open-ended interviews were conducted with 30 adult patients who had undergone carpal tunnel release or ulnar nerve decompression at the elbow 6-24 months prior. Interviews were digitally audio recorded and transcribed, and the data subjected to thematic analysis. Four overarching themes emerged from the data: (1) most patients did not perceive their condition to be serious; (2) patients were satisfied with the overall surgical experience; (3) the outcome was more important to patients than the process; and (4) majority of patients had a realistic expectation of outcomes. Patients had a positive experience with carpal tunnel and ulnar nerve decompression surgery, although their level of satisfaction was dependent on the surgical outcome. Areas requiring improvement, specifically information about post-operative care and expectations of recovery, will be implemented in the future care of patients.

  11. Nerve Decompression and Restless Legs Syndrome: A Retrospective Analysis.

    PubMed

    Anderson, James C; Fritz, Megan L; Benson, John-Michael; Tracy, Brian L

    2017-01-01

    Restless legs syndrome (RLS) is a prevalent sleep disorder affecting quality of life and is often comorbid with other neurological diseases, including peripheral neuropathy. The mechanisms related to RLS symptoms remain unclear, and treatment options are often aimed at symptom relief rather than etiology. RLS may present in distinct phenotypes often described as "primary" vs. "secondary" RLS. Secondary RLS is often associated with peripheral neuropathy. Nerve decompression surgery of the common and superficial fibular nerves is used to treat peripheral neuropathy. Anecdotally, surgeons sometimes report improved RLS symptoms following nerve decompression for peripheral neuropathy. The purpose of this retrospective analysis was to quantify the change in symptoms commonly associated with RLS using visual analog scales (VAS). Forty-two patients completed VAS scales (0-10) for pain, burning, numbness, tingling, weakness, balance, tightness, aching, pulling, cramping, twitchy/jumpy, uneasy, creepy/crawly, and throbbing, both before and 15 weeks after surgical decompression. Subjects reported significant improvement among all VAS categories, except for "pulling" (P = 0.14). The change in VAS following surgery was negatively correlated with the pre-surgery VAS for both the summed VAS (r = -0.58, P < 0.001) and the individual VAS scores (all P < 0.01), such that patients who reported the worst symptoms before surgery exhibited relatively greater reductions in symptoms after surgery. This is the first study to suggest improvement in RLS symptoms following surgical decompression of the common and superficial fibular nerves. Further investigation is needed to quantify improvement using RLS-specific metrics and sleep quality assessments.

  12. White matter changes linked to visual recovery after nerve decompression

    PubMed Central

    Paul, David A.; Gaffin-Cahn, Elon; Hintz, Eric B.; Adeclat, Giscard J.; Zhu, Tong; Williams, Zoë R.; Vates, G. Edward; Mahon, Bradford Z.

    2015-01-01

    The relationship between the integrity of white matter tracts and cortical function in the human brain remains poorly understood. Here we use a model of reversible white matter injury, compression of the optic chiasm by tumors of the pituitary gland, to study the structural and functional changes that attend spontaneous recovery of cortical function and visual abilities after surgical tumor removal and subsequent decompression of the nerves. We show that compression of the optic chiasm leads to demyelination of the optic tracts, which reverses as quickly as 4 weeks after nerve decompression. Furthermore, variability across patients in the severity of demyelination in the optic tracts predicts visual ability and functional activity in early cortical visual areas, and pre-operative measurements of myelination in the optic tracts predicts the magnitude of visual recovery after surgery. These data indicate that rapid regeneration of myelin in the human brain is a significant component of the normalization of cortical activity, and ultimately the recovery of sensory and cognitive function, after nerve decompression. More generally, our findings demonstrate the utility of diffusion tensor imaging as an in vivo measure of myelination in the human brain. PMID:25504884

  13. Decompression of inferior alveolar nerve: case report.

    PubMed

    Marques, Tiago Miguel Santos; Gomes, Joana Marques

    2011-01-01

    Paresthesia as a result of mechanical trauma is one of the most frequent sensory disturbances of the inferior alveolar nerve. This case report describes surgical treatment for paresthesia caused by a compressive phenomenon within the mandibular canal. The cause of the compression, a broken instrument left in the patient's mouth during previous endodontic therapy, was identified during routine radiography and computed tomography. Once the foreign object was removed by surgery, the paresthesia resolved quickly. This case highlights the potential for an iatrogenic mechanical cause of paresthesia.

  14. Leptomeningeal metastasis of an intradural malignant peripheral nerve sheath tumor.

    PubMed

    Stark, Andreas M; Mehdorn, H Maximilian

    2013-08-01

    Malignant peripheral nerve sheath tumors (MPNST) are defined as any malignant tumor arising from or differentiating towards the peripheral nerve sheath. Intradural MPNST metastases are very rare. We report, to our knowledge, the first case of leptomeningeal metastasis of a MPNST to the spine and intracranial space. A 56-year-old woman with primary intradural MPNST of the S1 nerve root developed leptomeningeal metastases as well as brain metastases 19 months after diagnosis. The patient had a history of non-Hodgkins lymphoma for which she had received irradiation to the spine 15 years prior to this presentation. She had no stigmata of neurofibromatosis type 1. Patients with MPNST may also develop leptomeningeal metastases as demonstrated in this patient with intradural post-radiation MPNST.

  15. Effect of optic nerve sheath fenestration for idiopathic intracranial hypertension on retinal nerve fiber layer thickness.

    PubMed

    Starks, Victoria; Gilliland, Grant; Vrcek, Ivan; Gilliland, Connor

    2016-01-01

    The objective of the study was to evaluate whether optic nerve sheath fenestration in patients with idiopathic intracranial hypertension was associated with improvement in visual field pattern deviation and optical coherence tomography retinal nerve fiber layer thickness.The records of 13 eyes of 11 patients who underwent optic nerve sheath fenestration were reviewed. The subjects were patients of a clinical practice in Dallas, Texas. Charts were reviewed for pre- and postoperative visual field pattern deviation (PD) and retinal nerve fiber layer thickness (RNFL).PD and RNFL significantly improved after surgery. Average PD preoperatively was 8.51 DB and postoperatively was 4.80 DB (p = 0.0002). Average RNFL preoperatively was 113.63 and postoperatively was 102.70 (p = 0.01). The preoperative PD and RNFL did not correlate strongly.Our results demonstrate that PD and RNFL are improved after optic nerve sheath fenestration. The pre- and postoperative RNFL values were compared to the average RNFL value of healthy optic nerves obtained from the literature. Post-ONSF RNFL values were significantly closer to the normal value than preoperative. RNFL is an objective parameter for monitoring the optic nerve after optic nerve sheath fenestration. This study adds to the evidence that OCT RNFL may be an effective monitoring tool for patients with IIH and that it continues to be a useful parameter after ONSF.

  16. Therapy of Experimental Nerve Sheath Tumors Using Oncolytic Viruses

    DTIC Science & Technology

    2005-06-01

    SUPPLEMENTARY NOTES 14. ABSTRACT Abstract follows. 15. SUBJECT TERMS Oncolytic HSV, angiogenesis, MPNST , mouse model 16. SECURITY CLASSIFICATION OF: 17...reliable tumor models for malignant peripheral nerve sheath tumors ( MPNST ). Several existing and novel oncolytic HSV vectors will then be tested on these...from G47A increases cytotoxicity in vitro to human endothelial cells and murine Nfl" MPNST cell lines. Inhibition of MPNST M2 tumor growth in vivo was

  17. Differential expression of angiogenic factors in peripheral nerve sheath tumors.

    PubMed

    Wasa, Junji; Nishida, Yoshihiro; Suzuki, Yoshitaka; Tsukushi, Satoshi; Shido, Yoji; Hosono, Kozo; Shimoyama, Yoshie; Nakamura, Shigeo; Ishiguro, Naoki

    2008-01-01

    It is difficult to differentiate some malignant peripheral nerve sheath tumors (MPNST) from benign peripheral nerve sheath tumors (BPNST) histologically, and to predict the clinical outcome of patients with MPNST. In this study, the expression of VEGF and MVD were evaluated immunohistochemically in 22 cases of MPNST, 14 of neurofibroma and 19 of schwannoma and correlation of the staining grade of VEGF or MVD and the various clinical factors were analyzed, and statistically evaluated. Levels of VEGF mRNA expression were also determined with real-time RT-PCR. Statistically higher positive staining for VEGF was observed in MPNST compared to neurofibroma (P=0.004) and schwannoma (P<0.001). Even low grade MPNST showed higher VEGF positive staining than neurofibroma. Moreover, high VEGF expression statistically correlated with the poor prognosis of the patients with MPNST (P=0.015). Although MVD in MPNST was significantly higher than that in neurofibroma (P=0.038) and schwannoma (P<0.001), MVD could not predict the prognosis of the patients with MPNST. Although VEGF mRNA expression tended to be higher in MPNST compared to neurofibroma, the difference was not significant. Levels of VEGF protein expression serve as a novel diagnostic and prognostic tools for peripheral nerve sheath tumors.

  18. Optic nerve sheath meningioma: current diagnosis and treatment.

    PubMed

    Eddleman, Christopher S; Liu, James K

    2007-01-01

    Optic nerve sheath meningiomas (ONSMs) are rare tumors of the anterior visual pathway and constitute approximately 2% of all orbital tumors and 1-2% of all meningiomas. Untreated ONSMs almost always lead to progressive visual decline, color blindness, and finally complete loss of vision. Although resection is warranted in cases of widespread ONSM, surgery can lead to significant morbidity. Recently, stereotactic fractionated radiotherapy has shown effectiveness in improving or stabilizing remaining visual function with minimal procedural morbidity in patients with ONSM. The authors review the incidence, histopathological characteristics, clinical presentation, neuroimaging findings, and current treatment modalities for ONSMs, with an emphasis on fractionated stereotactic radiotherapy.

  19. Characterization of the Biomechanical Behavior of the Optic Nerve Sheath

    NASA Technical Reports Server (NTRS)

    Raykin, Julia; Wang, Roy; Forte, Taylor E.; Feola, Andrew; Samuels, Brian; Myers, Jerry; Nelson, Emily; Gleason, Rudy; Ethier, C. Ross

    2016-01-01

    A major priority in current space medicine research is to characterize the mechanisms in Visual Impairment and Intracranial Pressure (VIIP) syndrome, a group of ophthalmic changes that occur in some astronauts following long-duration spaceflight [1]. It is hypothesized that microgravity-induced cephalad fluid shifts lead to increases in intracranial pressure (ICP), which drives maladaptive remodeling of the optic nerve sheath (ONS). In this study, we investigated the effects of mechanical loading on the porcine ONS to better understand the mechanical response of the ONS to increased ICP.

  20. Cystic change in primary paediatric optic nerve sheath meningioma.

    PubMed

    Narayan, Daniel; Rajak, Saul; Patel, Sandy; Selva, Dinesh

    2016-08-01

    Primary optic nerve sheath meningiomas (PONSM) are rare in children. Cystic meningiomas are an uncommon subgroup of meningiomas. We report a case of paediatric PONSM managed using observation alone that underwent cystic change and radiological regression. A 5-year-old girl presented with visual impairment and proptosis. Magnetic resonance (MR) imaging demonstrated a PONSM. The patient was left untreated and followed up with regular MR imaging. Repeat imaging at 16 years of age showed the tumour had started to develop cystic change. Repeat imaging at 21 years of age showed the tumour had decreased in size.

  1. [Intrathoracic giant peripheral nerve sheath tumor during Von Recklinghausen disease].

    PubMed

    Ngabou, U D; Mounguengui, D; Owono Mbouengou, J P; El Wali, A; Nguema Edzang, B; Boguikouma, J B; Tchoua, R; Aziz, N E

    2014-06-01

    We report the case of a patient aged 23, admitted for bilateral intrathoracic tumor, including a giant right. Surgery was performed by right sternothoracotomy. After 7 days, she presented an irreversible cardiac arrest. The malignant peripheral nerve sheath tumors are rare and aggressive. Their incidence is 0.001% in the general population and 0.16% in patients with neurofibromatosis type 1. These tumors are characterized by their risk of recurrence and poor prognosis. The treatment is the surgical resection. We analyze incidence, diagnosis and prognosis of these tumors.

  2. Microgravity-Driven Optic Nerve/Sheath Biomechanics Simulations

    NASA Technical Reports Server (NTRS)

    Ethier, C. R.; Feola, A.; Myers, J. G.; Nelson, E.; Raykin, J.; Samuels, B.

    2016-01-01

    Visual Impairment and Intracranial Pressure (VIIP) syndrome is a concern for long-duration space flight. Current thinking suggests that the ocular changes observed in VIIP syndrome are related to cephalad fluid shifts resulting in altered fluid pressures [1]. In particular, we hypothesize that increased intracranial pressure (ICP) drives connective tissue remodeling of the posterior eye and optic nerve sheath (ONS). We describe here finite element (FE) modeling designed to understand how altered pressures, particularly altered ICP, affect the tissues of the posterior eye and optic nerve sheath (ONS) in VIIP. METHODS: Additional description of the modeling methodology is provided in the companion IWS abstract by Feola et al. In brief, a geometric model of the posterior eye and optic nerve, including the ONS, was created and the effects of fluid pressures on tissue deformations were simulated. We considered three ICP scenarios: an elevated ICP assumed to occur in chronic microgravity, and ICP in the upright and supine positions on earth. Within each scenario we used Latin hypercube sampling (LHS) to consider a range of ICPs, ONH tissue mechanical properties, intraocular pressures (IOPs) and mean arterial pressures (MAPs). The outcome measures were biomechanical strains in the lamina cribrosa, optic nerve and retina; here we focus on peak values of these strains, since elevated strain alters cell phenotype and induce tissue remodeling. In 3D, the strain field can be decomposed into three orthogonal components, denoted as first, second and third principal strains. RESULTS AND CONCLUSIONS: For baseline material properties, increasing ICP from 0 to 20 mmHg significantly changed strains within the posterior eye and ONS (Fig. 1), indicating that elevated ICP affects ocular tissue biomechanics. Notably, strains in the lamina cribrosa and retina became less extreme as ICP increased; however, within the optic nerve, the occurrence of such extreme strains greatly increased as

  3. Optic Nerve Sheath Meningioma Masquerading as Optic Neuritis

    PubMed Central

    Alroughani, R.; Behbehani, R.

    2016-01-01

    Optic neuritis is a common presentation of demyelinating disorders such as multiple sclerosis. It typically presents with acute painful monocular vision loss, whereas chronic optic neuropathy can be caused by compressive lesions along the anterior visual pathway, genetic, toxic, or nutritional causes. We report an unusual presentation mimicking optic neuritis, which was subsequently diagnosed as optic nerve sheath meningioma (ONSM). Misinterpretation of white matter lesions on MRI of brain and the failure to image the optic nerves at the time of acute loss of vision led to the misdiagnosis of optic neuritis in this case. A comprehensive accurate history and ordering the appropriate imaging modality remain paramount in diagnosing progressive visual deterioration. PMID:26904329

  4. Study of malignant peripheral nerve sheath tumor in cerebellopontine angle.

    PubMed

    Hong, WenMing; Cheng, HongWei; Wang, XiaoJie; Hu, XiaoPeng; Feng, ChunGuo

    2014-01-01

    Malignant peripheral nerve sheath tumors (MPNSTs) are very rare soft tissue sarcomas, usually arising from somatic soft tissues or peripheral nerves. Primary MPNST of the cerebellopontine angle is extremely rare, with only a single case reported so far. Here, we report an unusual case of MPNST in cerebellopontine angle in a 25-year-old man presented with dizziness, left facial numbness, and tinnitus. After hospitalization, the tumor was treated with complete surgical excision followed by adjuvant chemotherapy and radiotherapy. Histologically, the tumor showed malignant spindle cells, which were with focal S-100 positivity on immunohistochemistry, and a diagnosis of the MPNST was made. This case is being reported for its rarity and presence in cerebellopontine and illustrated the difficulties in the diagnosis and treatment of MPNST, which to the best of our knowledge, has not been described before in the soft tissue sarcomas.

  5. Finite Element Biomechanics of Optic Nerve Sheath Traction in Adduction.

    PubMed

    Shin, Andrew; Yoo, Lawrence; Park, Joseph; Demer, Joseph L

    2017-10-01

    Historical emphasis on increased intraocular pressure (IOP) in the pathogenesis of glaucoma has been challenged by the recognition that many patients lack abnormally elevated IOP. We employed finite element analysis (FEA) to infer contribution to optic neuropathy from tractional deformation of the optic nerve head (ONH) and lamina cribrosa (LC) by extraocular muscle (EOM) counterforce exerted when optic nerve (ON) redundancy becomes exhausted in adduction. We characterized assumed isotropic Young's modulus of fresh adult bovine ON, ON sheath, and peripapillary and peripheral sclera by tensile elongation in arbitrary orientations of five specimens of each tissue to failure under physiological temperature and humidity. Physical dimensions of the FEA were scaled to human histological and magnetic resonance imaging (MRI) data and used to predict stress and strain during adduction 6 deg beyond ON straightening at multiple levels of IOP. Young's modulus of ON sheath of 44.6 ± 5.6 MPa (standard error of mean) greatly exceeded that of ON at 5.2 ± 0.4 MPa, peripapillary sclera at 5.5 ± 0.8 MPa, and peripheral sclera at 14.0 ± 2.3 MPa. FEA indicated that adduction induced maximum stress and strain in the temporal ONH. In the temporal LC, the maximum stress was 180 kPa, and the maximum strain was ninefold larger than produced by IOP elevation to 45 mm Hg. The simulation suggests that ON sheath traction by adduction concentrates far greater mechanical stress and strain in the ONH region than does elevated IOP, supporting the novel concept that glaucomatous optic neuropathy may result at least partly from external traction on the ON, rather than exclusively on pressure on the ON exerted from within the eye.

  6. Composite pheochromocytoma with a malignant peripheral nerve sheath tumor: Case report and review of the literature.

    PubMed

    Namekawa, Takeshi; Utsumi, Takanobu; Imamoto, Takashi; Kawamura, Koji; Oide, Takashi; Tanaka, Tomoaki; Nihei, Naoki; Suzuki, Hiroyoshi; Nakatani, Yukio; Ichikawa, Tomohiko

    2016-07-01

    Adrenal tumors with more than one cellular component are uncommon. Furthermore, an adrenal tumor composed of a pheochromocytoma and a malignant peripheral nerve sheath tumor is extremely rare. A composite pheochromocytoma with malignant peripheral nerve sheath tumor in a 42-year-old man is reported here. After adequate preoperative control, left adrenalectomy was performed simultaneously with resection of the ipsilateral kidney for spontaneous rupture of the left adrenal tumor. Pathological findings demonstrated pheochromocytoma and malignant peripheral nerve sheath tumor in a ruptured adrenal tumor. To date, there have been only four reported cases of composite pheochromocytoma with malignant peripheral nerve sheath tumor, so the present case is only the fifth case in the world. Despite the very poor prognosis of patients with pheochromocytoma and malignant peripheral nerve sheath tumors reported in the literature, the patient remains well without evidence of recurrence or new metastatic lesions at 36 months postoperatively. Copyright © 2012. Published by Elsevier Taiwan.

  7. Feline cutaneous nerve sheath tumours: histological features and immunohistochemical evaluations.

    PubMed

    Mandara, M T; Fabriani, E; Pavone, S; Pumarola, M

    2013-10-01

    Feline cutaneous nerve sheath tumours (CNSTs) are uncommonly reported in the skin, since they are underestimated relative to the more common spindle cell tumours of soft tissue. In this study, 26 nerve sheath tumours selected from 337 skin neoplasms of cats were examined. Histologically, they were classified into malignant (MPNSTs) and benign tumours (BPNSTs) based on degree of cellular atypia and polymorphism as well as mitotic rate and diffuse necrosis. CPNSTs were tipically characterised by Antoni A pattern, in some cases associated with Antoni B pattern. In the malignant peripheral nerve sheath tumours (MPNSTs) the polymorphism was marked, while it was mild to moderate in the benign forms (BPNSTs). In the MPNSTs the mitotic activity was generally higher than in the BPNSTs. In five cases, including three MPNSTs and two BPNSTs, there were multinucleated giant cells. Necrotic foci occurred in a BPNST and in two MPNSTs, while osseous/chondroid metaplasia was found in two cases. Immunohistochemically, all the tumours showed a marked diffuse vimentin expression. S-100 protein was expressed in 17 cases, including 81.8% of BPNSTs and 57.14% of MPNSTs. Twenty-five tumours expressed NSE and twenty-four cases showed immunoreaction for laminin. Thirteen tumours were positive for GFAP, while five tumours were positive for SMA. PGP 9.5 expression was detected in all cases, except for two MPNSTs. NGFR was expressed in eleven cases, including four MPNSTs and seven BPNSTs. Ki67 was expressed in twenty tumours without any relationship with morphologic malignancy of the neoplasm. In this case series we confirmed neoplastic spindloid cells with wavy cytoplasm arranged in compact areas, with occasional nuclear palisading or whirls, and interchanged with loosely arranged areas, as the morphological features supporting a diagnosis of CPNST. A constant concurrent expression of vimentin, NSE, and laminin might confirm the diagnosis of PNST in the absence of clear S-100 protein

  8. Pudendal nerve decompression in perineology : a case series

    PubMed Central

    Beco, Jacques; Climov, Daniela; Bex, Michèle

    2004-01-01

    Background Perineodynia (vulvodynia, perineal pain, proctalgia), anal and urinary incontinence are the main symptoms of the pudendal canal syndrome (PCS) or entrapment of the pudendal nerve. The first aim of this study was to evaluate the effect of bilateral pudendal nerve decompression (PND) on the symptoms of the PCS, on three clinical signs (abnormal sensibility, painful Alcock's canal, painful "skin rolling test") and on two neurophysiological tests: electromyography (EMG) and pudendal nerve terminal motor latencies (PNTML). The second aim was to study the clinical value of the aforementioned clinical signs in the diagnosis of PCS. Methods In this retrospective analysis, the studied sample comprised 74 female patients who underwent a bilateral PND between 1995 and 2002. To accomplish the first aim, the patients sample was compared before and at least one year after surgery by means of descriptive statistics and hypothesis testing. The second aim was achieved by means of a statistical comparison between the patient's group before the operation and a control group of 82 women without any of the following signs: prolapse, anal incontinence, perineodynia, dyschesia and history of pelvi-perineal surgery. Results When bilateral PND was the only procedure done to treat the symptoms, the cure rates of perineodynia, anal incontinence and urinary incontinence were 8/14, 4/5 and 3/5, respectively. The frequency of the three clinical signs was significantly reduced. There was a significant reduction of anal and perineal PNTML and a significant increase of anal richness on EMG. The Odd Ratio of the three clinical signs in the diagnosis of PCS was 16,97 (95% CI = 4,68 – 61,51). Conclusion This study suggests that bilateral PND can treat perineodynia, anal and urinary incontinence. The three clinical signs of PCS seem to be efficient to suspect this diagnosis. There is a need for further studies to confirm these preliminary results. PMID:15516268

  9. Light and electron microscopic alterations in spinal cord myelin sheaths after decompression sickness.

    PubMed

    Sykes, J J; Yaffe, L J

    1985-09-01

    Pathological examination of spinal cords from animals subjected to experimental decompression sickness (DCS) was undertaken in an attempt to explain the disparate response to treatment observed. Eight experimental animals, four undived control animals, and two dived but untreated animals were perfusion fixed, and the spinal cords were removed. Light microscopy of toluidine blue stained, ultrathin sections from dived animals demonstrated a distinctive widened myelin sheath showing a banded pattern of myelin disruption. This pattern was confirmed by electron microscopy and showed the separation to be between abutting double layers of myelin. Artifactual changes were also present in dived and undived animals. These previously unreported changes may be caused by DCS. They are compatible with the major mechanisms proposed in the pathophysiology of spinal cord DCS and may also account for the response to treatment seen in our experimental animals. It is suggested that these findings may also explain the response to treatment seen in patients, together with the formation of late lesions described in the spinal cords of long-term survivors of DCS.

  10. Malignant peripheral nerve sheath tumour in a sow.

    PubMed

    Resende, Talita P; Pereira, Carlos E R; Vannucci, Fabio A; Araujo, Fernando S; dos Santos, José Lúcio; Cassali, Geovanni D; Damasceno, Karine A; Guedes, Roberto M C

    2015-09-25

    Nodular lung lesions in swine are frequently due to abscesses or granulomatous pneumonia. Although tumours are rarely reported in modern pig farming, they should be considered as a differential diagnosis when nodular lung lesions are found. A first-parity sow exhibiting respiratory signs was euthanized. Several whitish firm nodules, not encapsulated, ranging in diameter from 0.5 to 5 cm were present in all lung lobes. Microscopically, the nodules were composed of dense neoplastic cells, mainly in Antoni types A and B patterns, infiltrative and with development of emboli. All neoplastic cells stained positively by immunohistochemistry for vimentin and S-100 protein, with variable immunostaining for glial fibrillary acidic protein and stained negative for cytokeratin. Based on the gross, histological and immunohistochemical features, the tumor was diagnosed as malignant peripheral nerve sheath tumour.

  11. Sarcoma of possible nerve sheath origin in a captive muskrat.

    PubMed

    Borucinska, J D; Trettel, J; Knibbs, D

    2000-07-01

    A captive adult female muskrat (Ondatra zibethicus) was found dead without previous signs of disease. At necropsy, abdominal organs were infiltrated with a poorly demarcated, soft, tan tissue. Microscopically this tissue was composed of neoplastic cells assuming two distinct growth characteristics consistent with Antoni A and B patterns. Ultrastructurally, the neoplastic cells were pleomorphic, lacked junctional devices, had abundant mitochondria and ergastoplasm, and frequently were closely associated with extracellular collagen. Immunocytochemical examination of tumor cells demonstrated sporadic expression of neuron specific enolase. Microscopic tumor metastases to the myocardium, ascending aorta, lungs and visceral pleura were present. This is the first report of a sarcoma compatible with a malignant peripheral nerve sheath tumor in a muskrat.

  12. Cerebral malignant nerve sheath tumor, triton tumor variant: case report.

    PubMed

    Bornstein-Quevedo, Leticia; Peralta-Olvera, Fabiola; Marhx-Bracho, Alfonso; Rodríguez-Jurado, Rodolfo; De Leon-Bojorge, Beatriz

    2003-01-01

    A case of a cerebral malignant triton tumor in a 3-year-old boy with a 2-month history of frontal headache and no clinical evidence of neurofibromatosis is reported. The computed tomography (CT) scan showed a large, irregular tumor in the right parietooccipital lobe. A partial surgical resection was performed. Histologically, the tumor was highly cellular and consisted of spindle cells with hyperchromatic and pleomorphic nuclei. Focally, neoplastic cells with rhabdomyoblastic features were found. The immunohistochemical study showed that tumor cells were positive for S-100 protein and CD57, and the rhabdomyoblasts expressed desmin, Myo-D1, and myoglobin. During the postoperative period, a massive intraparenchymal hemorrhage was identified and surgical drainage was performed. The patient worsened and died 10 days after the first surgery. Postmortem study was not authorized. Six cases of cerebral malignant nerve sheath tumor have been described; however, primary intraparenchymal malignant triton tumor has not been previously described.

  13. Nerve sheath myxoma of the dorsal paravertebral space

    PubMed Central

    Malkoc, Melih; Ormeci, Tugrul; Keskinbora, Mert; Yılmaz, Adem; Korkmaz, Ozgur; Tanik, Canan Besleyici

    2014-01-01

    INTRODUCTION Nerve sheath myxomas (NSM) are rare benign soft tissue tumors. The dorsal paravertebral placed NMS diagnosis can be difficult. PRESENTATION OF CASE This article presents clinical, radiological findings and treatment of the NSM of the dorsal paravertebral space in a 32-year-old man presented with a right shoulder and back pain for 4 years. DISCUSSION NSM is a rare and benign tumor and that most often occurs in the skin of the head, neck or upper limbs of younger patients. Rare locations such as intracranial, spinal canal, trunk, lower limb and oral cavity were also reported. The appropriate treatment of NSM is surgical excision. Diagnosis is difficult in an uncommon presentation. CONCLUSION Although the most presented case of NMS are dermal tumors, it may also be found extremely rare locations. We conclude that, the definitive treatment of NSM is surgical excision with safe margins even when it is possible. PMID:25462051

  14. Targeting the ECM to Enhance Drug Delivery in Nf1-Associated Nerve Sheath Tumors

    DTIC Science & Technology

    2016-10-01

    AWARD NUMBER: W81XWH-15-1-0114 TITLE: Targeting the ECM to Enhance Drug Delivery in Nf1-Associated Nerve Sheath Tumors PRINCIPAL INVESTIGATOR...14 Sep 2016 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER NF140089 Targeting the ECM to Enhance Drug Delivery in Nf1-Associated Nerve Sheath Tumors 5b...to determine what factors limit delivery of drugs to tumors of the peripheral nerves, namely neurofibromas (NFs) and their derivative, the malignant

  15. Intermediate nerve neuralgia can be diagnosed and cured by microvascular decompression.

    PubMed

    Chen, Yili; Song, Zhengfei; Wan, Yingfeng; Lin, Wei; Hu, Xingyue; Wang, Yirong; Imai, Hideaki

    2014-07-01

    Here, we present a case of a 55-year-old woman with a 10-year history of hemifacial spasm accompanied by 1-month ipsilateral paroxysmal otalgia. Magnetic resonance imaging revealed the presence of vessels around the facial nerve root. Surgical exploration via suboccipital retromastoid craniotomy showed converging compression of the facial nerve root and intermediate nerve from both sides by an anterior inferior cerebellar artery loop. The patient's hemifacial spasm and ipsilateral otalgia were completely relieved after microvascular decompression of the facial nerve root and intermediate nerve. Intraoperative findings and the postoperative result of this case confirmed that vascular compression of the intermediate nerve was the exclusive cause of paroxysmal otalgia. The presence of ipsilateral hemifacial spasm, combined with preoperative neuroimaging studies, contributed to the diagnosis of intermediate nerve neuralgia. Microvascular decompression should be considered for the management of patients with intermediate nerve neuralgia.

  16. Reconstruction of nerve root sheaths for sacral extradural spinal meningeal cysts with spinal nerve root fibers.

    PubMed

    Sun, Jianjun; Wang, Zhenyu; Li, Zhendong; Wu, Haibo; Yen, Ruyu; Zheng, Mei; Chang, Qing; Liu, Isabelle Yisha

    2013-11-01

    This study analyzed the clinical characteristics and outcomes of sacral extradural spinal meningeal cysts with spinal nerve root fibers treated by reconstruction of the nerve root sheaths. The relationships between the cysts and spinal nerve root fibers were examined microscopically, the cysts were partially excised, and the defects were oversewn to reconstruct the nerve root sheaths. The Improved Japanese Orthopedic Association (IJOA) scoring system was used to evaluate preoperative and postoperative neurological function. Thirty-eight patients were included in this study, with a mean age of 41.4 ± 15.57 years. The mean IJOA score was 18.8 ± 1.32 preoperatively and 19.6 ± 0.65 postoperatively, which was a significant difference (t=-3.77, P=0.001). These results indicate a significant improvement in neurological function after surgery. The most significant improvement in neurological function was sensation (z=-2.86, P=0.004), followed by bowel/bladder function (z=-2.31, P=0.02).

  17. Biomechanics of the Optic Nerve Sheath in VIIP Syndrome

    NASA Technical Reports Server (NTRS)

    Ethier, C. Ross; Raykin, Julia; Gleason, Rudy; Mulugeta, Lealem; Myers, Jerry; Nelson, Emily; Samuels, Brian C.

    2014-01-01

    Long-duration space flight carries the risk of developing Visual Impairment and Intracranial Pressure (VIIP) syndrome, a spectrum of ophthalmic changes including posterior globe flattening, choroidal folds, distension of the optic nerve sheath (ONS), optic nerve kinking and potentially permanent degradation of visual function. The slow onset of VIIP, its chronic nature, and certain clinical features strongly suggest that biomechanical factors acting on the ONS play a role in VIIP. Here we measure several relevant ONS properties needed to model VIIP biomechanics. The ONS (meninges) of fresh porcine eyes (n7) was reflected, the nerve proper was truncated near the sclera, and the meninges were repositioned to create a hollow cylinder of meningeal connective tissue attached to the posterior sclera. The distal end was cannulated, sealed, and pressure clamped (mimicking cerebrospinal fluid [CSF] pressure), while the eye was also cannulated for independent control of intraocular pressure (IOP). The meninges were inflated (CSF pressure cycling 7-50 mmHg) while ONS outer diameter was imaged. In another set of experiments (n4), fluid permeation rate across the meninges was recorded by observing the drainage of an elevated fluid reservoir (30 mmHg) connected to the meninges. The ONS showed behavior typical of soft tissues: viscoelasticity, with hysteresis in early preconditioning cycles and repeatable behavior after 4 cycles, and nonlinear stiffening, particularly at CSF pressures 15 mmHg (Figure). Tangent moduli measured from the loading curve were 372 101, 1199 358, and 2050 379 kPa (mean SEM) at CSF pressures of 7, 15 and 30 mmHg, respectively. Flow rate measurements through the intact meninges at 30mmHg gave a permeability of 1.34 0.46 lmincm2mmHg (mean SEM). The ONS is a tough, strain-stiffening connective tissue that is surprisingly permeable. The latter observation suggests that there could be significant CSF drainage through the ONS into the orbit, likely important

  18. Optic Nerve Sheath Mechanics and Permeability in VIIP Syndrome

    NASA Technical Reports Server (NTRS)

    Raykin, Julia; Best, Lauren; Gleason, Rudy; Mulugeta, Lealem; Myers, Jerry; Nelson, Emily; Samuels, Brian C.; Ethier, C. R.

    2014-01-01

    Long-duration space flight carries the risk of developing Visual Impairment and Intracranial Pressure (VIIP) syndrome, a spectrum of ophthalmic changes including posterior globe flattening, choroidal folds, distension of the optic nerve sheath (ONS), optic nerve kinking and potentially permanent degradation of visual function. The slow onset of VIIP, its chronic nature, and certain clinical features strongly suggest that biomechanical factors acting on the ONS play a role in VIIP. Here we measure several relevant ONS properties needed to model VIIP biomechanics. The ONS (meninges) of fresh porcine eyes (n7) was reflected, the nerve proper was truncated near the sclera, and the meninges were repositioned to create a hollow cylinder of meningeal connective tissue attached to the posterior sclera. The distal end was cannulated, sealed, and pressure clamped (mimicking cerebrospinal fluid [CSF] pressure), while the eye was also cannulated for independent control of intraocular pressure (IOP). The meninges were inflated (CSF pressure cycling 7-50 mmHg) while ONS outer diameter was imaged. In another set of experiments (n4), fluid permeation rate across the meninges was recorded by observing the drainage of an elevated fluid reservoir (30 mmHg) connected to the meninges. The ONS showed behavior typical of soft tissues: viscoelasticity, with hysteresis in early preconditioning cycles and repeatable behavior after 4 cycles, and nonlinear stiffening, particularly at CSF pressures 15 mmHg (Figure). Tangent moduli measured from the loading curve were 372 101, 1199 358, and 2050 379 kPa (mean SEM) at CSF pressures of 7, 15 and 30 mmHg, respectively. Flow rate measurements through the intact meninges at 30mmHg gave a permeability of 1.34 0.46 lmincm2mmHg (mean SEM). The ONS is a tough, strain-stiffening connective tissue that is surprisingly permeable. The latter observation suggests that there could be significant CSF drainage through the ONS into the orbit, likely important

  19. Prevention and Treatment of Neurofibromatosis Type 1-Associated Malignant Peripheral Nerve Sheath Tumors

    DTIC Science & Technology

    2016-04-01

    notwithstanding any other provision of law, no person shall be subject to any penalty for failing to comply with a collection of information if it does...ABSTRACT The most common cause of death in Neurofibromatosis Type 1 (NF1) patients is malignant peripheral nerve sheath tumor (MPNST). MPNSTs are...expectancy by ten to twenty years. Malignant peripheral nerve sheath tumors (MPNSTs) are the leading cause of death in NF1 patients and typically arise

  20. Receptor Tyrosine Kinases as Targets for Treatment of Peripheral Nerve Sheath Tumors in NF 1 Patients

    DTIC Science & Technology

    2010-03-01

    by interphase cytogenetics (FISH) in malignant peripheral nerve sheath tumor (MPNST) and morphologically similar spindle cell neoplasms . J...Chronic myeloproliferative disorders with rearrangement of the platelet-derived growth factor alpha receptor: a new clinical target for STI571/Glivec...malignant peripheral nerve sheath tumor (MPNST) and morphologically similar spindle cell neoplasms . J Neuropathol Exp Neurol. 2002;61:702–709. 8

  1. Optic Nerve Sheath Diameter Increase on Ascent to High Altitude: Correlation With Acute Mountain Sickness.

    PubMed

    Kanaan, Nicholas C; Lipman, Grant S; Constance, Benjamin B; Holck, Peter S; Preuss, James F; Williams, Sarah R

    2015-09-01

    Elevated optic nerve sheath diameter on sonography is known to correlate with increased intracranial pressure and is observed in acute mountain sickness. This study aimed to determine whether optic nerve sheath diameter changes on ascent to high altitude are associated with acute mountain sickness incidence. Eighty-six healthy adults enrolled at 1240 m (4100 ft), drove to 3545 m (11,700 ft) and then hiked to and slept at 3810 m (12,500 ft). Lake Louise Questionnaire scores and optic nerve sheath diameter measurements were taken before, the evening of, and the morning after ascent. The incidence of acute mountain sickness was 55.8%, with a mean Lake Louise Questionnaire score ± SD of 3.81 ± 2.5. The mean maximum optic nerve sheath diameter increased on ascent from 5.58 ± 0.79 to 6.13 ± 0.73 mm, a difference of 0.91 ± 0.55 mm (P = .09). Optic nerve sheath diameter increased at high altitude regardless of acute mountain sickness diagnosis; however, compared to baseline values, we observed a significant increase in diameter only in those with a diagnosis of acute mountain sickness (0.57 ± 0.77 versus 0.21 ± 0.76 mm; P = .04). This change from baseline, or Δ optic nerve sheath diameter, was associated with twice the odds of developing acute mountain sickness (95% confidence interval, 1.08-3.93). The mean optic nerve sheath diameter increased on ascent to high altitude compared to baseline values, but not to a statistically significant degree. The magnitude of the observed Δ optic nerve sheath diameter was positively associated with acute mountain sickness diagnosis. No such significant association was found between acute mountain sickness and diameter elevation above standard cutoff values, limiting the utility of sonography as a diagnostic tool. © 2015 by the American Institute of Ultrasound in Medicine.

  2. [Malignant intracerebral nerve sheath tumours: Two case reports and complete review of the literature cases].

    PubMed

    Le Fèvre, C; Castelli, J; Perrin, C; Hénaux, P L; Noël, G

    2016-04-01

    Malignant peripheral nerve sheath tumours are extremely rare and can be associated with neurofibramatosis type 1. Their prognosis is poor and surgery remains the mainstay of therapy and should be the first line of treatment. Radiotherapy and chemotherapy are second line treatment and their effectiveness remains to demonstrate. The diagnosis is clinical, radiological, histological and immunohistochemical. Malignant peripheral nerve sheath tumours have a potential of local tumour recurrence very high and can metastasize. They often occur in extremity of the members but also rarely into brain. We report two cases of intracerebral nerve sheath tumour. The first was a 68-year-old woman who was admitted with progressive symptoms of headache and diplopia. A left frontotemporal malignant peripheral nerve sheath tumours was diagnosed and was treated by surgery and irradiation. Ten months later, she presented a local recurrence and spine bone's metastases were treated by vertebroplasty and irradiation. The patient died 15 months after the diagnosis. The second case was a 47-year-old woman who was referred because headache and vomiting symptoms. A right frontal malignant peripheral nerve sheath tumours was diagnosed and treated by surgery and irradiation. After that, the patient had three local recurrence operated and pulmonary and cranial bone's metastases. She was still alive after 20 months. We propose a literature review with 25 cases of intracerebral nerve sheath tumour identified, including the two current cases.

  3. Palliative Epineurotomy for Focal Radial Malignant Peripheral Nerve Sheath Tumor in a Dog.

    PubMed

    Gibson, Andrew David; Davies, Emma; Lara-Garcia, Ana; Lafuente, Pilar

    2016-01-01

    This case report describes the diagnosis of a peripheral nerve sheath tumor of the deep branch of the radial nerve distal to the elbow in a dog. The lesion was identified using computed tomography and ultrasonography and confirmed as sarcoma on histopathological analysis of incisional biopsies. Clinical signs dramatically improved following surgical biopsy before recurring three months later. Repeat epineurotomy of the deep branch of the radial nerve resulted in clinical improvement for a further month before signs once again returned. Epineurotomy as a palliative treatment for peripheral nerve sheath tumors has not been previously described, but may have a place in palliation of clinical signs in specific cases of peripheral nerve sheath tumors in which limb amputation is not an option.

  4. Therapeutic efficacy of G207 in a novel peripheral nerve sheath tumor model.

    PubMed

    Mashour, G A; Moulding, H D; Chahlavi, A; Khan, G A; Rabkin, S D; Martuza, R L; Driever, P H; Kurtz, A; Chalavi, A

    2001-05-01

    Nerve involvement poses a significant obstacle for the management of peripheral nervous system tumors, and nerve injury provides a frequent source of postoperative morbidity. The lack of suitable animal models for peripheral nerve tumors has impeded the development of alternative nerve-sparing therapies. To evaluate the effect of a multimutated replication-competent herpes simplex virus (G207) on the growth of peripheral nerve tumors and on nerve function, we developed a novel peripheral nerve sheath tumor model. Human neuroblastoma-derived cells injected into murine sciatic nerve consistently caused tumor development within the nerve sheath after 2 weeks followed by increasingly severe impairment of nerve function. Tumor treatment by a single intratumoral injection of G207 resulted in significant reduction of functional impairment, inhibition of tumor growth and prolonged survival. Direct injection of G207 viral particles into the healthy nerve sheath caused no obvious neurologic sequelae, whereas injections of wild-type virus resulted in uniform lethality. The results indicate that viral therapy might be considered as a safe alternative to surgical removal of tumors with peripheral nerve involvement. Copyright 2001 Academic Press.

  5. Optic nerve compartment syndrome in a patient with optic nerve sheath meningioma.

    PubMed

    Jaggi, G P; Mironov, A; Huber, A R; Killer, H E

    2007-01-01

    To report a patient with optic nerve (ON) sheath meningioma, unilateral optic disc swelling, and inhomogeneous cerebrospinal fluid (CSF) composition between lumbar CSF and CSF from the subarachnoid space (SAS) of the affected ON. A 39-year-old woman presented with unilateral optic disc swelling and slight deterioration of visual function in the left eye. Extensive laboratory workup and magnetic resonance imaging (MRI) of the brain and orbits were performed. As radiotherapy was refused by the patient, ON sheath fenestration (ONSF) was offered and performed in order to stop deterioration. CSF from the SAS of the ON was sampled. Laboratory workup was within normal limits. MRI of the left orbit demonstrated enhancement of the dura in the precanalicular portion of the ON and distension of the SAS, most prominent in the bulbar portion of the ON. On lumbar puncture the opening pressure measured 19 (cm H2O). Compared to the lumbar CSF the CSF of the affected ON SAS showed markedly elevated measurements for albumin, IgG, and beta-trace protein. Visual function remained stable over a follow-up time of 18 months. Composition of CSF is considered to be homogenous throughout all CSF spaces. In this patient the authors found a marked concentration-gradient of albumin, IgG, and beta-trace protein between the CSF in the spinal canal and the CSF in the SAS of the affected ON. Based on the radiologic features of the left ON and the dissociated beta-trace protein concentrations in the CSF of the SAS of the ON and the lumbar CSF, the diagnosis of an ON sheath compartment syndrome due to an ON sheath meningioma was made.

  6. Fractionated Stereotactic Radiotherapy in Patients With Optic Nerve Sheath Meningioma

    SciTech Connect

    Paulsen, Frank; Doerr, Stefan; Wilhelm, Helmut; Becker, Gerd; Bamberg, Michael; Classen, Johannes

    2012-02-01

    Purpose: To evaluate the effectiveness of fractionated stereotactic radiotherapy (SFRT) in the treatment of optic nerve sheath meningioma (ONSM). Methods and Materials: Between 1993 and 2005, 109 patients (113 eyes) with primary (n = 37) or secondary (n = 76) ONSM were treated according to a prospective protocol with SFRT to a median dose of 54 Gy. All patients underwent radiographic, ophthalmologic, and endocrine analysis before and after SFRT. Radiographic response, visual control, and late side effects were endpoints of the analysis. Results: Median time to last clinical, radiographic, and ophthalmologic follow up was 30.2 months (n = 113), 42.7 months (n = 108), and 53.7 months (n = 91), respectively. Regression of the tumor was observed in 5 eyes and progression in 4 eyes, whereas 104 remained stable. Visual acuity improved in 12, deteriorated in 11, and remained stable in 68 eyes. Mean visual field defects reduced from 33.6% (n = 90) to 17.8% (n = 56) in ipsilateral and from 10% (n = 94) to 6.7% (n = 62) in contralateral eyes. Ocular motility improved in 23, remained stable in 65, and deteriorated in 3 eyes. Radiographic tumor control was 100% at 3 years and 98% at 5 years. Visual acuity was preserved in 94.8% after 3 years and in 90.9% after 5 years. Endocrine function was normal in 90.8% after 3 years and in 81.3% after 5 years. Conclusions: SFRT represents a highly effective treatment for ONSM. Interdisciplinary counseling of the patients is recommended. Because of the high rate of preservation of visual acuity we consider SFRT the standard approach for the treatment of ONSM. Prolonged observation is warranted to more accurately assess late visual impairment. Moderate de-escalation of the radiation dose might improve the preservation of visual acuity and pituitary gland function.

  7. Alterations at chromosome 17 loci in peripheral nerve sheath tumors

    SciTech Connect

    Lothe, R.A.; Slettan, A.; Saeter, G.

    1995-01-01

    Little is known about the molecular genetic changes in malignant peripheral nerve sheath tumors (MPNST). Inactivation of the TP53 gene in l7p has been reported in a few tumors. The MPNST is one of the manifestations of neurofibromatosis 1 (NF1), suggesting that the NF1 gene in 17q might be important. We present a study of 15 neurofibromas and MPNST from nine individuals. Seven patients had NF1 and six of these developed MPNST. Genetic alterations at nine polymorphic loci on chromosome 17 were examined. Allelic imbalance was detected only in the malignant tumors from NF1 patients (4/6). Complete loss of heterozygosity of 17q loci was found in three of these tumors, all including loci within the NF1 gene. Two of the malignant tumors also showed deletions on 17p. No mutations were detected within exon 5-8 of the TP53 in any of the MPNST, and none of them were TP53 protein-positive using immunostaining with mono- and polyclonal antibodies against TP53. The numbers of chromosome 17 present in each tumor were evaluated by use of fluorescence in situ hybridization (FISH) on interphase nuclei with a centromere-specific probe. A deviation from the disomic status of chromosome 17 was observed in two of the MPNST from NF1 patients. These results support the hypothesis of inactivation of both NF1 gene alleles during development of MPNST in patients with NF1. In contrast to other reports, we did not find evidence for a homozygous mutated condition of the TP53 gene in the same tumors. Finally, FISH analysis was in accordance with the DNA analysis in the deduction of the numbers of chromosome 17 in these tumors. 29 refs., 3 figs., 2 tabs.

  8. Predictors of surgical revision after in situ decompression of the ulnar nerve.

    PubMed

    Krogue, Justin D; Aleem, Alexander W; Osei, Daniel A; Goldfarb, Charles A; Calfee, Ryan P

    2015-04-01

    This study was performed to identify factors associated with the need for revision surgery after in situ decompression of the ulnar nerve for cubital tunnel syndrome. This case-control investigation examined all patients treated at one institution with open in situ decompression for cubital tunnel syndrome between 2006 and 2011. The case patients were 44 failed decompressions that required revision, and the controls were 79 randomly selected patients treated with a single operation. Demographic data and disease-specific data were extracted from the medical records. The rate of revision surgery after in situ decompression was determined from our 5-year experience. A multivariate logistic regression model was used based on univariate testing to determine predictors of revision cubital tunnel surgery. Revision surgery was required in 19% (44 of 231) of all in situ decompressions performed during the study period. Predictors of revision surgery included a history of elbow fracture or dislocation (odds ratio [OR], 7.1) and McGowan stage I disease (OR, 3.2). Concurrent surgery with in situ decompression was protective against revision surgery (OR, 0.19). The rate of revision cubital tunnel surgery after in situ nerve decompression should be weighed against the benefits of a less invasive procedure compared with transposition. When considering in situ ulnar nerve decompression, prior elbow fracture as well as patients requesting surgery for mild clinically graded disease should be viewed as risk factors for revision surgery. Patient factors often considered relevant to surgical outcomes, including age, sex, body mass index, tobacco use, and diabetes status, were not associated with a greater likelihood of revision cubital tunnel surgery. Copyright © 2015 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  9. Giant intrapelvic malignant peripheral nerve sheath tumor mimicking disc herniation: A case report

    PubMed Central

    Wang, Peng; Chen, Cong; Xin, Xiaotang; Liu, Bo; Li, Wei; Yin, Dezhen; Mu, Weidong

    2016-01-01

    Giant intrapelvic malignant peripheral nerve sheath tumors arising in the sciatic nerve in the pelvic cavity are a rare occurrence and their symptomatology is usually misdiagnosed as intervertebral disc herniation. We herein report the case of a 46-year old woman presenting with pain, hypesthesia and weakness of the left lower extremity due to a giant intrapelvic malignant peripheral nerve sheath tumor of the sciatic nerve. Prior to being referred to our institution, the patient was misdiagnosed as a case of sciatica due to a lumbar disc herniation and underwent an operation unsuccessfully, as there was little symptomatic improvement 2 months after the surgery. A magnetic resonance imaging examination of the pelvic cavity revealed a tumor of the sciatic nerve. The mass was resected via the posterior approach and histopathological examination confirmed the diagnosis of malignant peripheral nerve sheath tumor. Intrapelvic malignant peripheral nerve sheath tumors are an uncommon cause of sciatica and are commonly misdiagnosed as lumbar intervertebral disc herniation. Accurate diagnosis and complete surgical excision prior to metastasis are crucial for effective management of this condition. PMID:27900106

  10. A Rare Malignant Peripheral Nerve Sheath Tumor of the Maxilla Mimicking a Periapical Lesion

    PubMed Central

    Álvares, Pamella; Silva, Luciano; Pereira dos Santos Neto, Alexandrino; Rodrigues, Cleomar Donizeth; Caubi, Antônio; Silveira, Marcia; Sayão, Sandra; Sobral, Ana Paula

    2016-01-01

    Malignant peripheral nerve sheath tumor is a malignant neoplasm that is rarely found in the oral cavity. About 50% of this tumor occurs in patients with neurofibromatosis type I and comprises approximately 10% of all soft tissue sarcomas of head and neck region. Intraosseous malignant peripheral nerve sheath tumor of the maxilla is rare. This article is the first to address malignant peripheral nerve sheath tumor of the maxilla presenting as a periapical radiolucency on nonvital endodontically treated teeth in the English medical literature. Surgical approaches to malignant soft tissue tumor vary based on the extent of the disease, age of the patient, and pathological findings. A rare case of intraosseous malignant peripheral nerve sheath tumor is reported in a 16-year-old woman. The patient presented clinically with a pain involving the upper left incisors region and with defined unilocular periapical radiolucency lesion involved between the upper left incisors. An incisional biopsy was made. Histological and immunohistochemical examination were positive for S-100 protein and glial fibrillary acidic protein showed that the lesion was an intraosseous malignant peripheral nerve sheath tumor of the maxilla. Nine years after the surgery, no regional recurrence was observed. PMID:27994888

  11. Staged image guided robotic radiosurgery for optic nerve sheath meningiomas.

    PubMed

    Romanelli, Pantaleo; Bianchi, Livia; Muacevic, Alexander; Beltramo, Giancarlo

    2011-01-01

    Optic nerve sheath meningiomas (ONSMs) represent the most challenging lesions involving the optic pathways: Microsurgery is not indicated and classical single-stage radiosurgery appears to be too risky due to the expected destruction of the common blood supply with consequent loss of vision. Staged radiosurgery might be one treatment option because it exploits the ability of normal tissues to repair sub-lethal radiation-induced damage, offering a chance to control tumor growth while sparing function. Staged robotic radiosurgery was offered to 5 patients harboring ONSMs with the aim of sparing vision while achieving local growth control. Five patients with ONSM presenting with visual field deficits and loss of visual acuity were treated with staged CyberKnife radiosurgery, receiving 20 Gy in 4 stages (5 Gy per stage). Treatment planning was based on contrast-enhanced thin-slice CT (1.25 mm thickness for the first three cases, 0.5 mm for the last two) and volumetric MR imaging (1.5 T for the first three cases, 3 T for the last two). An interval of 24 hours was strictly observed between stages. Visual acuity and visual fields were assessed in all patients immediately prior to treatment and at intervals of 6 months thereafter. Follow-up MRIs were performed every 6 months for 2 years, then once per year. The entire procedure, inclusive of imaging, treatment planning and treatment delivery, was performed in 5 days. Irradiation required approximately 45 min per stage. Mean tumor volume was 2.94 cc (range: 0.8-6.4 cc). Treatment was well tolerated in all patients. Follow-up ranged from 36 to 74 months. Local growth control was achieved in all patients. Restoration of normal vision was experienced by 4 patients 6 to 12 months after the treatment. One patient, who was also affected by diabetic retinopathy, showed a modest improvement after 6 months, remaining stable thereafter. Staged CyberKnife radiosurgery provides a fast and well-tolerated non

  12. Analysis and Visualization of Nerve Vessel Contacts for Neurovascular Decompression

    NASA Astrophysics Data System (ADS)

    Süßmuth, Jochen; Piazza, Alexander; Enders, Frank; Naraghi, Ramin; Greiner, Günther; Hastreiter, Peter

    Neurovascular compression syndromes are caused by a pathological contact between cranial nerves and vascular structures at the surface of the brainstem. Aiming at improved pre-operative analysis of the target structures, we propose calculating distance fields to provide quantitative information of the important nerve-vessel contacts. Furthermore, we suggest reconstructing polygonal models for the nerves and vessels. Color-coding with the respective distance information is used for enhanced visualization. Overall, our new strategy contributes to a significantly improved clinical understanding.

  13. Accuracy and complications of CT-guided core needle biopsy of peripheral nerve sheath tumours.

    PubMed

    Pianta, Marcus; Chock, Eric; Schlicht, Stephen; McCombe, David

    2015-09-01

    This single-centre study retrospectively reviews the complications in patients that have occurred following peripheral nerve sheath tumour biopsy, and assesses whether there is an association with biopsy technique or underlying lesion characteristics. 41 consecutive core needle biopsies of proven peripheral nerve sheath tumours over a 2-year period in a tertiary teaching hospital were reviewed. Patient demographics and symptoms, tumour characteristics and radiological appearances were recorded. Biopsy and surgical histology were correlated, and post-biopsy and surgical complications analyzed. 41 biopsies were performed in 38 patients. 68% schwannomas, 24% neurofibromas and 7% malignant peripheral nerve sheath tumours. Biopsy histology correlated with surgery in all cases. 71% of lesions were surgically excised. 60% of patients reported pain related to their lesion. Following the biopsy, 12% reported increased pain, which resolved in all cases. Pain exacerbation was noted in tumours smaller in size, more superficial and in closer proximity of the biopsy needle tip to the traversing nerve. Number of biopsy needle passes was not associated with an increased incidence of procedure-related pain. Core biopsy of a suspected peripheral nerve sheath tumour may be performed safely before excisional surgery to confirm lesion histology and assist prognosis. There is excellent correlation between core biopsy and excised surgical specimen histology. The most common complication of pain exacerbation is seen in a minority and is temporary, and more likely with smaller, more superficial lesions and a closer needle-tip to traversing nerve distance during biopsy.

  14. Nerve decompression and neuropathy complications in diabetes: Are attitudes discordant with evidence?

    PubMed

    Nickerson, D Scott

    2017-01-01

    External neurolysis of the nerve at fibro-osseous tunnels has been proprosed to treat or prevent signs, symptoms, and complications in the lower extremity of diabetes patients with sensorimotor polyneuropathy. Nerve decompression is justified in the presence of symptomatic compressed nerves in the several fibro-osseous tunnels of the extremities, which are known to be frequent in diabetes. Quite a body of literature has accumulated reporting results after such nerve decompression in the leg, describing pain relief and sensibility improvement, as well as balance recovery, diabetic foot ulcer prevention, curtailed ulcer recurrence risk, and amputation avoidance. Historical academic hesitance to endorse surgical treatments for pain and numbness in diabetes was based primarily on the early retrospective reports' potential for bias and placebo effects, and that the hypothetical basis for surgery lies outside the traditional etiology paradigm of length-dependent axonopathy. This reticence is here critiqued in view of recent studies using objective, measured outcome protocols which nullify such potential confounders. Pain relief is now confirmed with Level 1 studies, and Level 2 prospective information suggests protection from initial diabetic foot ulceration and most neuropathic ulcer recurrences. In view of the potential for nerve decompression to be useful in addressing some of the more difficult, expensive, and life altering complications of diabetic neuropathy, this secondary compression thesis and operative treatment methodology may deserve reassessment.

  15. Endoscopic extradural anterior clinoidectomy and optic nerve decompression through a pterional port.

    PubMed

    Beer-Furlan, André; Evins, Alexander I; Rigante, Luigi; Burrell, Justin C; Anichini, Giulio; Stieg, Philip E; Bernardo, Antonio

    2014-05-01

    Since the first description of the intradural removal of the anterior clinoid process, numerous refinements and modifications have been proposed to simplify and enhance the safety of the technique. The growing use of endoscopes in endonasal and transcranial approaches has changed the traditional management of many skull base lesions. We describe an endoscopic extradural anterior clinoidectomy and optic nerve decompression through a minimally invasive pterional port. Minimally invasive optic nerve decompression, with endoscopic extradural anterior clinoidectomy, through a pterional keyhole craniotomy was performed on five preserved cadaveric heads. The endoscopic pterional port provided a shorter and more direct route to the anterior clinoid region, and helped avoid unnecessary and extensive bone removal. An extradural approach helped minimize complications associated with infraction of the subdural space and allowed for the maintenance of visibility while drilling with continuous irrigation. Adequate 270° bone decompression of the optic canal was achieved in all specimens. Endoscopic extradural anterior clinoidectomy and optic nerve decompression is feasible through a single minimally invasive pterional port.

  16. Macrovascular Decompression of the Brainstem and Cranial Nerves: Evolution of an Anteromedial Vertebrobasilar Artery Transposition Technique.

    PubMed

    Choudhri, Omar; Connolly, Ian D; Lawton, Michael T

    2017-08-01

    Tortuous and dolichoectatic vertebrobasilar arteries can impinge on the brainstem and cranial nerves to cause compression syndromes. Transposition techniques are often required to decompress the brainstem with dolichoectatic pathology. We describe our evolution of an anteromedial transposition technique and its efficacy in decompressing the brainstem and relieving symptoms. To present the anteromedial vertebrobasilar artery transposition technique for macrovascular decompression of the brainstem and cranial nerves. All patients who underwent vertebrobasilar artery transposition were identified from the prospectively maintained database of the Vascular Neurosurgery service, and their medical records were reviewed retrospectively. The extent of arterial displacement was measured pre- and postoperatively on imaging. Vertebrobasilar arterial transposition and macrovascular decompression was performed in 12 patients. Evolution in technique was characterized by gradual preference for the far-lateral approach, use of a sling technique with muslin wrap, and an anteromedial direction of pull on the vertebrobasilar artery with clip-assisted tethering to the clival dura. With this technique, mean lateral displacement decreased from 6.6 mm in the first half of the series to 3.8 mm in the last half of the series, and mean anterior displacement increased from 0.8 to 2.5 mm, with corresponding increases in satisfaction and relief of symptoms. Compressive dolichoectatic pathology directed laterally into cranial nerves and posteriorly into the brainstem can be corrected with anteromedial transposition towards the clivus. Our technique accomplishes this anteromedial transposition from an inferolateral surgical approach through the vagoaccessory triangle, with sling fixation to clival dura using aneurysm clips.

  17. Vagal nerve stimulation without dissecting the carotid sheath during intraoperative neuromonitoring of the recurrent laryngeal nerve in thyroid surgery.

    PubMed

    Wu, Che-Wei; Dionigi, Gianlorenzo; Chen, Hui-Chun; Chen, Hsiu-Ya; Lee, Ka-Wo; Lu, I-Cheng; Chang, Pi-Ying; Hsiao, Pi-Jung; Ho, Kuen-Yao; Chiang, Feng-Yu

    2013-10-01

    Vagal nerve stimulation (VNS) has been recommended as a routine procedure during intraoperative neuromonitoring (IONM) of the recurrent laryngeal nerve (RLN). However, many surgeons have been discouraged from performing VNS because of the need for opening the carotid sheath. The purpose of this study was to investigate the feasibility and reliability of VNS without carotid sheath dissection. Two hundred twenty patients with 376 nerves at risk were enrolled in this study. VNS without nerve exposure during IONM was applied by simply pressing a ball-tip stimulator on the space between the carotid artery and jugular vein. VNS without nerve exposure was feasible in all cases and did not result in any morbidity. All VNS signals were successfully obtained within 30 minutes of the start of the operation and all showed a clear and reliable laryngeal electromyography (EMG) response that was similar to that from the conventional method in which nerve exposure for VNS is applied. VNS without dissecting the carotid sheath is feasible and reliable, rendering it a simple, safe, and surgeon-friendly procedure during IONM. Copyright © 2013 Wiley Periodicals, Inc.

  18. Ultrastructure of the extracellular matrix of bovine dura mater, optic nerve sheath and sclera.

    PubMed Central

    Raspanti, M; Marchini, M; Della Pasqua, V; Strocchi, R; Ruggeri, A

    1992-01-01

    The sclera, the outermost sheath of the optic nerve and the dura mater have been investigated histologically and ultrastructurally. Although these tissues appear very similar under the light microscope, being dense connective tissues mainly composed of collagen bundles and a limited amount of cells and elastic fibres, they exhibit subtle differences on electron microscopy. In the dura and sclera collagen appears in the form of large, nonuniform fibrils, similar to those commonly found in tendons, while in the optic nerve sheath the fibrils appear smaller and uniform, similar to those commonly observed in reticular tissues, vessel walls and skin. Freeze-fracture also reveals these fibrils to have different subfibrillar architectures, straight or helical, which correspond to 2 distinct forms of collagen fibril previously described (Raspanti et al. 1989). The other extracellular matrix components also vary with the particular collagen fibril structure. Despite their common embryological derivation, the dura mater, optic nerve sheath and sclera exhibit diversification of their extracellular matrix consistent with the mechanical loads to which these tissues are subjected. Our observations indicate that the outermost sheath of the optic nerve resembles the epineurium of peripheral nerves rather than the dura to which it is commonly likened. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 PMID:1295858

  19. [Indications and technique for transconjunctival optic nerve sheath fenestration : Video article].

    PubMed

    Lagrèze, W A; Gross, N; Biermann, J; Joachimsen, L

    2017-09-13

    Placement of a ventricular shunt is the primary surgical procedure for lowering intracranial pressure in pseudotumor cerebri syndrome; however, if ophthalmological symptoms prevail over neurological symptoms or if there are no neurological symptoms at all, optic nerve sheath fenestration may be a valuable option for relief of pressure on the retrobulbar optic nerve when papilledema caused by pseudotumor cerebri syndrome threatens vision despite previous conservative measures. This review covers the indications, technique and results of optic nerve sheath fenestration compared to competing procedures based on a systematic literature search, analysis of own cases and a documentation of the surgical technique. After performing a medial transconjunctival orbitotomy the medial rectus muscle tendon is temporarily detached and the eye abducted by traction sutures. Using confocal illumination under a surgical microscope, the optic nerve can be visualized using orbital spatulas and the sheath can be punctured with a microscalpel. A video of this operation is available online. Transconjunctival optic nerve sheath fenestration is a relatively safe method to reduce the rate of visual loss in pseudotumor cerebri syndrome. In selected cases it can be a useful alternative to ventriculoperitoneal/atrial shunts or venous stents.

  20. Pathology of Peripheral Nerve Sheath Tumors: Diagnostic Overview and Update on Selected Diagnostic Problems

    PubMed Central

    Rodriguez, Fausto J.; Folpe, Andrew L.; Giannini, Caterina; Perry, Arie

    2013-01-01

    Peripheral nerve sheath tumors are common neoplasms, with classic identifiable features, but on occasion, they are diagnostically challenging. Although well defined subtypes of peripheral nerve sheath tumors were described early in the history of surgical pathology, controversies regarding the classification and grading of these tumors persist. Advances in molecular biology have provided new insights into the nature of the various peripheral nerve sheath tumors, and have begun to suggest novel targeted therapeutic approaches. In this review we discuss current concepts and problematic areas in the pathology of peripheral nerve sheath tumors. Diagnostic criteria and differential diagnosis for the major categories of nerve sheath tumors are proposed, including neurofibroma, schwannoma, and perineurioma. Diagnostically challenging variants, including plexiform, cellular and melanotic schwannomas are highlighted. A subset of these affects the childhood population, and has historically been interpreted as malignant, although current evidence and outcome data suggests they represent benign entities. The growing current literature and the authors experience with difficult to classify borderline or “hybrid tumors” are discussed and illustrated. Some of these classification gray zones occur with frequency in the gastrointestinal tract, an anatomical compartment that must always be entertained when examining these neoplasms. Other growing recent areas of interest include the heterogeneous group of pseudoneoplastic lesions involving peripheral nerve composed of mature adipose tissue and/or skeletal muscle, such as the enigmatic neuromuscular choristoma. Malignant peripheral nerve sheath tumors (MPNST) represent a diagnostically controversial group; difficulties in grading and guidelines to separate “atypical neurofibroma” from MPNST are provided. There is an increasing literature of MPNST mimics which neuropathologists must be aware of, including synovial sarcoma and

  1. Neuropraxia of the palmar cutaneous branch of the ulnar nerve during carpal tunnel decompression.

    PubMed

    Akhtar, S; Arenas Prat, J; Sinha, S

    2005-05-01

    Carpal tunnel syndrome is one of the most commonly encountered conditions in the hand clinic and carpal tunnel decompression is the most frequently performed procedure in hand surgery. It is an effective procedure for patients with carpal tunnel syndrome. However, there is a high risk of complications that can be avoided with an understanding of wrist anatomy, appropriate planning and execution. We highlight one such complication, a case of neuropraxia of the palmar cutaneous branch of the ulnar nerve that followed carpal tunnel decompression.

  2. Neuropraxia of the palmar cutaneous branch of the ulnar nerve during carpal tunnel decompression.

    PubMed Central

    Akhtar, S.; Arenas Prat, J.; Sinha, S.

    2005-01-01

    Carpal tunnel syndrome is one of the most commonly encountered conditions in the hand clinic and carpal tunnel decompression is the most frequently performed procedure in hand surgery. It is an effective procedure for patients with carpal tunnel syndrome. However, there is a high risk of complications that can be avoided with an understanding of wrist anatomy, appropriate planning and execution. We highlight one such complication, a case of neuropraxia of the palmar cutaneous branch of the ulnar nerve that followed carpal tunnel decompression. PMID:16395819

  3. Changes in myelin sheath thickness and internode geometry in the rabbit phrenic nerve during growth.

    PubMed Central

    Friede, R L; Brzoska, J; Hartmann, U

    1985-01-01

    The rabbit phrenic nerve was studied at seven phases of growth from the newborn to the adult to determine the length of the nerve fibres, the length of the internodes, the fibre calibre, the geometric proportions of the internodes and the thickness of the myelin sheaths. The elongation of the internodes corresponded precisely to the elongation of the nerve, indicating a constant number of approximately 140 internodes per fibre, each internode elongating commensurate with body growth. Internode elongation was accompanied by increases in fibre calibre, but these parameters did not change in precise proportion. The internodes of thick fibres were relatively short for calibre, as defined by the length/diameter quotient. This trend of foreshortening changed during growth. Sheath thickness, defined by the quotient axon diameter/fibre diameter, was determined with a computer-assisted method. Fibres of young rabbits had relatively thin sheaths for axon calibre, compared with adult rabbits. The changes in sheath thickness corresponded to the changes in internode geometry. This was consistent with previous studies showing that elongation or foreshortening of an internode of a given calibre has a slight, but definite effect on the thickness of its myelin sheath. PMID:3870716

  4. Role of CD44 in Malignant Peripheral Nerve Sheath Tumor Growth and Metastasis

    DTIC Science & Technology

    2002-09-01

    Malignant peripheral nerve sheath tumors ( MPNSTs ) are aggressive malignancies that arise within peripheral nerves. These tumors occur with increased...and abnormal expression of the epidermal growth factor receptor (EGFR). We previously found that MPNSTs express increased levels of the CD44 family...kinase activity (and not increased Ras-GTP) contributes to MPNST cell invasion. We further find that EGFR contributes at least part of the elevated Src

  5. Macrovascular decompression of the median nerve for posttraumatic neuralgic limb pain.

    PubMed

    Pabaney, Aqueel; Hervey-Jumper, Shawn L; Domino, Joseph; Maher, Cormac O; Yang, Lynda J S

    2013-09-01

    Neuropathic pain is rare in children, and few reports provide adequate guidelines for treatment. The authors describe the successful treatment of tardy neuropathic pain via macrovascular decompression in a 15-year-old boy who presented with progressive pain 11 years following trauma to the upper extremity that had required surgical repair of the brachial artery. Examination revealed mild chronic median and ulnar motor neuropathy as well as recent progressive lancinating pain and a Tinel sign at the prior scar. A soft tissue mass in the neurovascular bundle at the site of previous injury was noted on MRI. Surgical exploration demonstrated an altered anatomical relationship of the previously repaired brachial artery and the median nerve, resulting in pulsatile compression of the median nerve by the brachial artery. Neurolysis and decompression of the median nerve with physical separation from the brachial artery resulted in immediate pain relief. This is the first report of macrovascular decompression of a major peripheral nerve with complete symptom resolution. Noninvasive imaging together with a thorough history and physical examination can support identification of this potential etiology of peripheral neuralgic pain. Recognition and treatment of this uncommon problem may yield improved outcomes for children with neuropathic pain.

  6. Do nerve conduction studies predict the outcome of carpal tunnel decompression?

    PubMed

    Bland, J D

    2001-07-01

    Patients (n = 3336) who had been tested for suspected carpal tunnel syndrome (CTS) were contacted by postal questionnaire and their opinions sought of the overall subjective outcome of any treatments using a five-point rating scale. Operative results were compared with preoperative nerve conduction, clinical and demographic variables, and a multiple logistic regression analysis used to identify significant prognostic factors. Among 1268 surgical procedures that were identified, the overall surgical success rate was 69%. Preoperative nerve conduction study findings, greater age, lower symptom scores, longer disease duration, and male gender were significant predictors of poor outcome. Nerve conduction studies had the strongest effect, with patients with middle-grade abnormalities having better results than those with either very severe or no abnormality. Surgical carpal tunnel decompression has a significant failure rate. The preoperative nerve conduction studies account for a proportion of the total variation in outcome. Copyright 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 935-940, 2001

  7. Receptor Tyrosine Kinases as Targets for Treatment of Peripheral Nerve Sheath Tumors in NF 1 Patients

    DTIC Science & Technology

    2007-03-01

    EGFR patterns by interphase cytogenetics (FISH) in malignant peripheral nerve sheath tumor (MPNST) and morphologically similar spindle cell neoplasms ...Armstrong,F., Delsol,G., Dastugue,N. and Brousset,P. (2003) Chronic myeloproliferative disorders with rearrangement of the platelet-derived growth

  8. Treatment of Peripheral Neuropathy in Leprosy: The Case for Nerve Decompression

    PubMed Central

    Wan, Eric L.; Rivadeneira, Andres F.; Jouvin, Renato Martinez

    2016-01-01

    Summary: Plastic surgery has a tradition of caring for patients with facial deformity and hand deformity related to leprosy. The approach, however, to the progressive deformity and disability related to chronic nerve compression is underappreciated in the world today. A cohort of patients with leprous neuropathy from an indigenous area of leprosy in Ecuador was evaluated for the presence of chronic peripheral nerve compression, and 12 patients were chosen for simultaneous upper and lower extremity, unilateral, nerve decompression at multiple levels along the course of each nerve. The results at 1 year of follow-up show that 6 patients improved into the excellent category and 4 patients improved into the good category for improved function. Based on the early results in this small cohort of patients with leprous neuropathy, an approach to peripheral nerve decompression, encompassing the concept of multiple crush at multiple levels of each nerve, seems to offer optimism to improve upper and lower extremity limb function. Long-term studies with quality-of-life outcomes would be welcome. PMID:27257567

  9. Peripheral Nerve Diffusion Tensor Imaging: Assessment of Axon and Myelin Sheath Integrity.

    PubMed

    Heckel, A; Weiler, M; Xia, A; Ruetters, M; Pham, M; Bendszus, M; Heiland, S; Baeumer, P

    2015-01-01

    To investigate the potential of diffusion tensor imaging (DTI) parameters as in-vivo biomarkers of axon and myelin sheath integrity of the median nerve in the carpal tunnel as validated by correlation with electrophysiology. MRI examinations at 3T including DTI were conducted on wrists in 30 healthy subjects. After manual segmentation of the median nerve quantitative analysis of fractional anisotropy (FA) as well as axial, radial and mean diffusivity (AD, RD, and MD) was carried out. Pairwise Pearson correlations with electrophysiological parameters comprising sensory nerve action potential (SNAP) and compound muscle action potential (CMAP) as markers of axon integrity, and distal motor latency (dml) and sensory nerve conduction velocity (sNCV) as markers of myelin sheath integrity were computed. The significance criterion was set at P=0.05, Bonferroni corrected for multiple comparisons. DTI parameters showed a distinct proximal-to-distal profile with FA, MD, and RD extrema coinciding in the center of the carpal tunnel. AD correlated with CMAP (r=0.50, p=0.04, Bonf. corr.) but not with markers of myelin sheath integrity. RD correlated with sNCV (r=-0.53, p=0.02, Bonf. corr.) but not with markers of axon integrity. FA correlated with dml (r=-0.63, p=0.002, Bonf. corr.) and sNCV (r=0.68, p=0.001, Bonf. corr.) but not with markers of axon integrity. AD reflects axon integrity, while RD (and FA) reflect myelin sheath integrity as validated by correlation with electrophysiology. DTI parameters consistently indicate a slight decrease of structural integrity in the carpal tunnel as a physiological site of median nerve entrapment. DTI is particularly sensitive, since these findings are observed in healthy participants. Our results encourage future studies to evaluate the potential of DTI in differentiating axon from myelin sheath injury in patients with manifest peripheral neuropathies.

  10. Methylation-based classification of benign and malignant peripheral nerve sheath tumors.

    PubMed

    Röhrich, Manuel; Koelsche, Christian; Schrimpf, Daniel; Capper, David; Sahm, Felix; Kratz, Annekathrin; Reuss, Jana; Hovestadt, Volker; Jones, David T W; Bewerunge-Hudler, Melanie; Becker, Albert; Weis, Joachim; Mawrin, Christian; Mittelbronn, Michel; Perry, Arie; Mautner, Victor-Felix; Mechtersheimer, Gunhild; Hartmann, Christian; Okuducu, Ali Fuat; Arp, Mirko; Seiz-Rosenhagen, Marcel; Hänggi, Daniel; Heim, Stefanie; Paulus, Werner; Schittenhelm, Jens; Ahmadi, Rezvan; Herold-Mende, Christel; Unterberg, Andreas; Pfister, Stefan M; von Deimling, Andreas; Reuss, David E

    2016-06-01

    The vast majority of peripheral nerve sheath tumors derive from the Schwann cell lineage and comprise diverse histological entities ranging from benign schwannomas and neurofibromas to high-grade malignant peripheral nerve sheath tumors (MPNST), each with several variants. There is increasing evidence for methylation profiling being able to delineate biologically relevant tumor groups even within the same cellular lineage. Therefore, we used DNA methylation arrays for methylome- and chromosomal profile-based characterization of 171 peripheral nerve sheath tumors. We analyzed 28 conventional high-grade MPNST, three malignant Triton tumors, six low-grade MPNST, four epithelioid MPNST, 33 neurofibromas (15 dermal, 8 intraneural, 10 plexiform), six atypical neurofibromas, 43 schwannomas (including 5 NF2 and 5 schwannomatosis associated cases), 11 cellular schwannomas, 10 melanotic schwannomas, 7 neurofibroma/schwannoma hybrid tumors, 10 nerve sheath myxomas and 10 ganglioneuromas. Schwannomas formed different epigenomic subgroups including a vestibular schwannoma subgroup. Cellular schwannomas were not distinct from conventional schwannomas. Nerve sheath myxomas and neurofibroma/schwannoma hybrid tumors were most similar to schwannomas. Dermal, intraneural and plexiform neurofibromas as well as ganglioneuromas all showed distinct methylation profiles. Atypical neurofibromas and low-grade MPNST were indistinguishable with a common methylation profile and frequent losses of CDKN2A. Epigenomic analysis finds two groups of conventional high-grade MPNST sharing a frequent loss of neurofibromin. The larger of the two groups shows an additional loss of trimethylation of histone H3 at lysine 27 (H3K27me3). The smaller one retains H3K27me3 and is found in spinal locations. Sporadic MPNST with retained neurofibromin expression did not form an epigenetic group and most cases could be reclassified as cellular schwannomas or soft tissue sarcomas. Widespread immunohistochemical loss

  11. Surgical strategies for managing foraminal nerve sheath tumors: the emerging role of CyberKnife ablation

    PubMed Central

    Murovic, Judith A.; Charles Cho, S.

    2009-01-01

    Sixteen Stanford University Medical Center (SUMC) patients with foraminal nerve sheath tumors had charts reviewed. CyberKnife radiosurgery was innovative in management. Parameters were evaluated for 16 foraminal nerve sheath tumors undergoing surgery, some with CyberKnife. Three neurofibromas had associated neurofibromatosis type 1 (NF1). Eleven patients had one resection; others had CyberKnife after one (two) and two (three) operations. The malignant peripheral nerve sheath tumor (MPNST) had prior field-radiation and adds another case. Approaches included laminotomy and laminectomies with partial (three) or total (two) facetectomies/fusions. Two cases each had supraclavicular, lateral extracavitary, retroperitoneal and Wiltze and costotransversectomy/thoracotomy procedures. Two underwent a laminectomy/partial facetectomy, then CyberKnife. Pre-CyberKnife, one of two others had a laminectomy/partial facetectomy, then total facetectomy/fusion and the other, two supraclavicular approaches. The MPNST had a hemi-laminotomy then laminectomy/total facetectomy/fusion, followed by CyberKnife. Roots were preserved, except in two. Of 11 single-operation-peripheral nerve sheath tumors, the asymptomatic case remained stable, nine (92%) improved and one (9%) worsened. Examinations remained intact in three (27%) and improved in seven (64%). Two having a single operation then CyberKnife had improvement after both. Of two undergoing two operations, one had symptom resolution post-operatively, worsened 4 years post-CyberKnife then has remained unchanged after re-operation. The other such patient improved post-operatively, had no change after re-operation and improved post-CyberKnife. The MPNST had presentation improvement after the first operation, worsened and after the second surgery \\and CyberKnife, the patient expired from tumor spread. In conclusion, surgery is beneficial for pain relief and function preservation in foraminal nerve sheath tumors. Open surgery with Cyber

  12. Surgical strategies for managing foraminal nerve sheath tumors: the emerging role of CyberKnife ablation.

    PubMed

    Murovic, Judith A; Charles Cho, S; Park, Jon

    2010-02-01

    Sixteen Stanford University Medical Center (SUMC) patients with foraminal nerve sheath tumors had charts reviewed. CyberKnife radiosurgery was innovative in management. Parameters were evaluated for 16 foraminal nerve sheath tumors undergoing surgery, some with CyberKnife. Three neurofibromas had associated neurofibromatosis type 1 (NF1). Eleven patients had one resection; others had CyberKnife after one (two) and two (three) operations. The malignant peripheral nerve sheath tumor (MPNST) had prior field-radiation and adds another case. Approaches included laminotomy and laminectomies with partial (three) or total (two) facetectomies/fusions. Two cases each had supraclavicular, lateral extracavitary, retroperitoneal and Wiltze and costotransversectomy/thoracotomy procedures. Two underwent a laminectomy/partial facetectomy, then CyberKnife. Pre-CyberKnife, one of two others had a laminectomy/partial facetectomy, then total facetectomy/fusion and the other, two supraclavicular approaches. The MPNST had a hemi-laminotomy then laminectomy/total facetectomy/fusion, followed by CyberKnife. Roots were preserved, except in two. Of 11 single-operation-peripheral nerve sheath tumors, the asymptomatic case remained stable, nine (92%) improved and one (9%) worsened. Examinations remained intact in three (27%) and improved in seven (64%). Two having a single operation then CyberKnife had improvement after both. Of two undergoing two operations, one had symptom resolution post-operatively, worsened 4 years post-CyberKnife then has remained unchanged after re-operation. The other such patient improved post-operatively, had no change after re-operation and improved post-CyberKnife. The MPNST had presentation improvement after the first operation, worsened and after the second surgery \\and CyberKnife, the patient expired from tumor spread. In conclusion, surgery is beneficial for pain relief and function preservation in foraminal nerve sheath tumors. Open surgery with Cyber

  13. Peripheral Nerve Diffusion Tensor Imaging: Assessment of Axon and Myelin Sheath Integrity

    PubMed Central

    Heckel, A.; Weiler, M.; Xia, A.; Ruetters, M.; Pham, M.; Bendszus, M.; Heiland, S.; Baeumer, P.

    2015-01-01

    Purpose To investigate the potential of diffusion tensor imaging (DTI) parameters as in-vivo biomarkers of axon and myelin sheath integrity of the median nerve in the carpal tunnel as validated by correlation with electrophysiology. Methods MRI examinations at 3T including DTI were conducted on wrists in 30 healthy subjects. After manual segmentation of the median nerve quantitative analysis of fractional anisotropy (FA) as well as axial, radial and mean diffusivity (AD, RD, and MD) was carried out. Pairwise Pearson correlations with electrophysiological parameters comprising sensory nerve action potential (SNAP) and compound muscle action potential (CMAP) as markers of axon integrity, and distal motor latency (dml) and sensory nerve conduction velocity (sNCV) as markers of myelin sheath integrity were computed. The significance criterion was set at P=0.05, Bonferroni corrected for multiple comparisons. Results DTI parameters showed a distinct proximal-to-distal profile with FA, MD, and RD extrema coinciding in the center of the carpal tunnel. AD correlated with CMAP (r=0.50, p=0.04, Bonf. corr.) but not with markers of myelin sheath integrity. RD correlated with sNCV (r=-0.53, p=0.02, Bonf. corr.) but not with markers of axon integrity. FA correlated with dml (r=-0.63, p=0.002, Bonf. corr.) and sNCV (r=0.68, p=0.001, Bonf. corr.) but not with markers of axon integrity. Conclusion AD reflects axon integrity, while RD (and FA) reflect myelin sheath integrity as validated by correlation with electrophysiology. DTI parameters consistently indicate a slight decrease of structural integrity in the carpal tunnel as a physiological site of median nerve entrapment. DTI is particularly sensitive, since these findings are observed in healthy participants. Our results encourage future studies to evaluate the potential of DTI in differentiating axon from myelin sheath injury in patients with manifest peripheral neuropathies. PMID:26114630

  14. Acute optic nerve sheath fenestration in humans using the free electron laser (FEL): a case report

    NASA Astrophysics Data System (ADS)

    Joos, Karen M.; Mawn, Louise A.; Shen, Jin-Hui; Jansen, E. Duco; Casagrande, Vivien A.

    2002-06-01

    Our previous studies using rabbits and monkeys showed that the Amide II wavelength (6.45 micrometers ) produced by the FEL could efficiently produce an optic nerve sheath fenestration with minimal damage. In order to determine if the technology safely could be applied to human surgery, we used 2 blind human eyes during enucleation to compare the results of producing fenestrations with the FEL or a scissors. FDA and Vanderbilt IRB approvals, and individual patient consents were obtained. The FEL energy was transmitted to a human operating room. After disinsertion of the medial rectus muscle, an optic nerve sheath fenestration (2 mm diameter) was made with either the FEL (6.45 micrometers , 325 micrometers spot size, 30 Hz, 3 mJ) through a hollow waveguide surgical probe or with a scissors. The enucleation was then completed. The optic nerve was dissected from the globe and fixed. Specimens were examined histologically. Dural incisions were effective with both methods. FEL energy at 6.45 micrometers can be transmitted to an operating room and delivered to human ocular tissue through a hollow waveguide surgical probe. This FEL wavelength can produce an optic nerve sheath fenestration without acute direct damage to the nerve in this case report.

  15. Morphometric Analysis of Connective Tissue Sheaths of Sural Nerve in Diabetic and Nondiabetic Patients

    PubMed Central

    Kundalić, Braca; Ugrenović, Slađana; Jovanović, Ivan; Stefanović, Natalija; Petrović, Vladimir; Kundalić, Jasen; Stojanović, Vesna; Živković, Vladimir; Antić, Vladimir

    2014-01-01

    One of the most common complications of diabetes mellitus is diabetic neuropathy. It may be provoked by metabolic and/or vascular factors, and depending on duration of disease, various layers of nerve may be affected. Our aim was to investigate influence of diabetes on the epineurial, perineurial, and endoneurial connective tissue sheaths. The study included 15 samples of sural nerve divided into three groups: diabetic group, peripheral vascular disease group, and control group. After morphological analysis, morphometric parameters were determined for each case using ImageJ software. Compared to the control group, the diabetic cases had significantly higher perineurial index (P < 0.05) and endoneurial connective tissue percentage (P < 0.01). The diabetic group showed significantly higher epineurial area (P < 0.01), as well as percentage of endoneurial connective tissue (P < 0.01), in relation to the peripheral vascular disease group. It is obvious that hyperglycemia and ischemia present in diabetes lead to substantial changes in connective tissue sheaths of nerve, particularly in peri- and endoneurium. Perineurial thickening and significant endoneurial fibrosis may impair the balance of endoneurial homeostasis and regenerative ability of the nerve fibers. Future investigations should focus on studying the components of extracellular matrix of connective tissue sheaths in diabetic nerves. PMID:25147820

  16. Superficial malignant peripheral nerve sheath tumor arising from diffuse neurofibroma in a neurofibromatosis type 1 patient.

    PubMed

    Inoue, Takuya; Kuwashiro, Maki; Misago, Noriyuki; Narisawa, Yutaka

    2014-07-01

    Malignant peripheral nerve sheath tumors (MPNST) are regarded as sarcomas that arise from peripheral nerves or that display differentiation along the lines of the various elements of the nerve sheath. These tumors occur in deep soft tissues, but superficial primary MPNST with a cutaneous or subcutaneous origin have rarely been reported. A 70-year-old woman presented with a 3-4-year history of a slowly enlarging soft nodule on the left side of her neck. The histopathological diagnosis of the nodule was low-grade MPNST arising from diffuse neurofibroma. There was increased cellularity, but no necrosis or mitotic activity. These histopathological findings pose difficulties in differential diagnosis from a neurofibroma with atypical histological features. We report a rare case of superficial MPNST arising from diffuse neurofibroma associated with underlying occipital bone dysplasia in a neurofibromatosis type 1 patient.

  17. Successful surgical optic nerve decompression in a patient with hypertrophic pachymeningitis due to granulomatous polyangiitis

    PubMed Central

    de Hoog, Joeri; Volovici, Victor; Dammers, Ruben

    2015-01-01

    A 57-year-old woman presented with subacute vision loss of first the left, and later the right eye. She was diagnosed with granulomatous polyangiitis with hypertrophic pachymeningitis and optic nerve compression. Her visual acuity could not be permanently restored with immune suppressants alone, so a surgical decompression of the right optic nerve, via a modified cranio-orbitozygomatic pretemporal approach, was performed. Her right eye regained 20/20 vision and has remained stable during 8 months of follow-up. PMID:25612758

  18. Outcomes following Peripheral Nerve Decompression with and without Associated Double Crush Syndrome: A Case Control Study.

    PubMed

    Wessel, Lauren E; Fufa, Duretti T; Canham, R Bruce; La Bore, Adam; Boyer, Martin I; Calfee, Ryan P

    2017-01-01

    Double crush syndrome, the association between proximal and distal nerve lesions, has been established. This investigation compares the outcomes of nerve surgery in patients with isolated peripheral compression versus those with double crush syndrome treated with peripheral nerve and cervical spine operations. This case-controlled study enrolled 80 patients: 40 underwent carpal or cubital tunnel surgery and cervical spine surgery (double crush group); and 40 controls, matched by age and sex, underwent only peripheral nerve decompression (peripheral nerve group). A minimum of 18 months was required after peripheral nerve and cervical spine surgery for office assessment (mean, 4.9 years and 6.0 years, respectively). Statistical analysis compared postoperative function and symptom severity questionnaires, physical examination, and patient-reported satisfaction between groups. Patients in the double crush group reported significantly more disability and persistent symptoms on the QuickDASH questionnaire (29 versus 13) and Levine Katz symptom severity (2.0 versus 1.4) and functional status scales (1.9 versus 1.4). Double crush patients reported significantly lower satisfaction. The double crush group exhibited a greater frequency of persistent signs of nerve irritability and muscle weakness compared with the control group. At a minimum of 18 months after peripheral nerve surgery, patients with a history of cervical spine surgery are likely to have inferior patient-reported outcomes, persistent nerve dysfunction, and lower satisfaction after peripheral nerve release compared with patients following isolated peripheral nerve surgery. Double crush syndrome was associated with poorer outcome after peripheral nerve surgery despite treatment of cervical spine nerve compression. Therapeutic, III.

  19. “Well Digging” Subcraniotomy Strategy with Navigation for Optic Nerve Decompression in Frontoorbital Fibrous Dysplasia: Preliminary Experience

    PubMed Central

    Lu, Yunhe; Yang, Junyi; Wu, Yingzhi; Pan, Sida; Lu, Jiawen

    2016-01-01

    Background: During the past decades, surgical intervention has been the primary treatment modality for frontoorbital fibrous dysplasia involving optic nerve. However, controversy has surrounded the role of optic nerve decompression in a number of ways. Herein, we describe 3 patients with frontoorbital fibrous dysplasia involving optic nerve, who underwent a “well digging” subcraniotomy strategy with navigation for intraorbital unit optic nerve decompression. Methods: From 2013 to 2015, 3 patients with frontoorbital fibrous dysplasia were investigated in a retrospective manner. They underwent unilateral intraorbital optic nerve decompression with the help of “well digging” strategy and navigation. The key procedures comprise preoperative software simulation, frontoorbital subcraniotomy (like digging a well), expanding cone-shaped surgical field, intraorbital unit optic nerve decompression with navigation, correcting frontal-orbital dystopias, and deformities. Results: Both at the immediate postoperative period and during the 3–12 months follow-up, 2 cases showed improvement of visual acuity in the affected eye and 1 case showed no deterioration. Other ocular examinations including eye movement were stable. Subsequent reconstruction yielded a satisfactory cosmetic result. No postoperative complications happened. Conclusions: In our philosophy, surgical management should be tailored to each patient, which is based on the most possible potential etiology. We consider that the intraorbital optic nerve decompression may be more feasible and safer with the help of “well digging” strategy and navigation, especially for those with exophthalmos, orbital volume decreasing, and nonacute visual loss. PMID:27975011

  20. Epicardial Ablation: Prevention of Phrenic Nerve Damage by Pericardial Injection of Saline and the Use of a Steerable Sheath

    PubMed Central

    Neven, Kars; Fernandez-Armenta, Juan; Andreu, David; Berruezo, Antonio

    2014-01-01

    Because of the close proximity of the phrenic nerve to the pericardium, phrenic nerve damage caused by epicardial ablation can easily occur. We report two cases of epicardial VT ablation where pericardial injection of saline, combined with the use of a steerable sheath, successfully prevents the phrenic nerve from being damaged. PMID:24669108

  1. Epicardial ablation: prevention of phrenic nerve damage by pericardial injection of saline and the use of a steerable sheath.

    PubMed

    Neven, Kars; Fernandez-Armenta, Juan; Andreu, David; Berruezo, Antonio

    2014-03-01

    Because of the close proximity of the phrenic nerve to the pericardium, phrenic nerve damage caused by epicardial ablation can easily occur. We report two cases of epicardial VT ablation where pericardial injection of saline, combined with the use of a steerable sheath, successfully prevents the phrenic nerve from being damaged.

  2. Cluster analysis of immunohistochemical profiles in synovial sarcoma, malignant peripheral nerve sheath tumor, and Ewing sarcoma.

    PubMed

    Olsen, Stephen H; Thomas, Dafydd G; Lucas, David R

    2006-05-01

    As a result of overlapping morphologic and immunohistochemical features, it can be difficult to distinguish synovial sarcoma, malignant peripheral nerve sheath tumor, and Ewing sarcoma/primitive neuroectodermal tumor in core biopsies. To analyze and compare immunohistochemical profiles, we stained tissue microarrays of 23 synovial sarcomas, 23 malignant peripheral nerve sheath tumors, and 27 Ewing sarcomas with 22 antibodies potentially useful in the differential diagnosis, and analyzed the data with cluster analysis. Stain intensity was scored as none, weak, or strong. For CD99, tumors with membranous accentuation were independently categorized. Cluster analysis sorted five groups, with like tumors clustering together. Synovial sarcoma clustered into two groups: one cytokeratin and EMA positive (n = 11), the other mostly cytokeratin negative, EMA positive, bcl-2 positive and mostly CD56 positive (n = 9). Malignant peripheral nerve sheath tumor clustered into two groups: one S100 positive, with nestin and NGFR positivity in most (n = 10), the other mostly S100 negative, and variably but mostly weakly positive for nestin and NGFR (n = 11). Ewing sarcomas clustered into a single group driven by membranous CD99 staining. Thirteen cases failed to cluster (outliers), while three Ewing sarcomas clustered into groups of other tumor types. Paired antibodies for each tumor type determined by visual assessment of cluster analysis data and statistical calculations of specificity, sensitivity, and predictive values showed that EMA/CK7 for synovial sarcoma, nestin/S100 for malignant peripheral nerve sheath tumor, and membranous CD99/Fli-1 for Ewing sarcoma yielded high specificity and positive predictive values. Cluster analysis also highlighted aberrant staining reactions and diagnostic pitfalls in these tumors. Hierarchical cluster analysis is an effective method for analyzing high-volume immunohistochemical data.

  3. Sporadic Multifocal Malignant Peripheral Nerve Sheath Tumor-A Rare Presentation: Multifocal MPNST.

    PubMed

    Leena, J B; Fernandes, Hilda; Swethadri, G K

    2013-06-01

    Malignant peripheral nerve sheath tumors(MPNST) are uncommon neoplasms with an incidence of 0.001% in general population. Multifocality is a rare manifestation of MPNST . A case of a 65 year old patient who presented with multiple swellings involving the neck, extremity and back without associated neurofibromatosis is reported for its rarity of presentation.. Diagnosis was made by FNAC and confirmed by peroperative findings and histopathology.

  4. Role of CD44 in Malignant Peripheral Nerve Sheath Tumor Growth and Metastasis

    DTIC Science & Technology

    2003-09-01

    Malignant peripheral nerve sheath tumors ( MPNST ) are aggressive, difficult to treat tumors that occur in type I neurofibromatosis patients with an...survival rate. We previously found that MPNSTs overexpress the CD44 tranmembrane glycoprotein and that reducing CD44 expression partially inhibits MPNST ...depends on Src kinase and that Src kinase activity promotes MPNST invasion (Su et al., 2003a) . Furthermore, we show that MPNST cell invasion depends on

  5. Role of CD44 in Malignant Peripheral Nerve Sheath Tumor Growth and Metastasis

    DTIC Science & Technology

    2001-09-01

    Malignant peripheral nerve sheath tumors ( MPNST ) are aggressive, difficult to treat tumors that occur in type I neurofibromatosis patients with an...survival rate. We previously found that MPNSTs overexpress the CD44 tranmembrane glycoprotein and that reducing Cc44 expression inhibits MPNST cell...Src kinase. Furthermore, we show that MPNST cell invasion depends on an autocrine loop involving MCF, an MCF activating enzyme (MGFA), and c-Met, all of

  6. Genetic Evaluation of Peripheral Nerve Sheath Tumors in Neurofibromatosis Type I

    DTIC Science & Technology

    2003-10-01

    neurofibromatosis type 1 (NF1). Archival and prospectively acquired plexiform neurofibromas and malignant peripheral nerve sheath tumors ( MPNSTs ) were collected...evaluated, whereas a relatively small number of MPNSTs have been collected for complete analysis. Immunohistochemical stains have been developed to...distinguish -high-grade versus low-grade MPNSTs and plexiform neurofibromas. The genome of plexiform neurofibromas is relatively stable, compared to the

  7. Novel Therapeutic Development of NF1-Associated Malignant Peripheral Nerve Sheath Tumor (MPNST)

    DTIC Science & Technology

    2016-08-01

    AWARD NUMBER: W81XWH-15-1-0124 TITLE: Novel Therapeutic Development of NF1- Associated Malignant Peripheral Nerve Sheath Tumor (MPNST...COVERED 15 Jul 2015 - 14 Jul 2016 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Novel Therapeutic Development of NF1- Associated Malignant Peripheral...components (EED or SUZ12), CDKN2A (81%) and NF1 (72% of non-NF1- associated ) in all MPNSTs, and the three components significantly co-occur, suggesting their

  8. Lost in translation: ambiguity in nerve sheath tumor nomenclature and its resultant treatment effect.

    PubMed

    Bernthal, Nicholas M; Jones, Kevin B; Monument, Michael J; Liu, Ting; Viskochil, David; Randall, R Lor

    2013-05-08

    There is much ambiguity surrounding the diagnosis of nerve sheath tumors, including atypical neurofibroma and low-grade MPNST, and yet, the distinction between these entities designates either benign or malignant behavior and thus carries presumed profound prognostic importance that often guides treatment. This study reviews the diagnostic criteria used to designate atypical neurofibroma from low-grade MPNSTs and reviews existing literature the natural history of each of these tumors to see if the distinction is, in fact, of importance.

  9. Malignant peripheral nerve sheath tumour in the ischio-rectal fossa.

    PubMed

    Teoh, K H; Reddy, S; Beggs, I; Al-Nafussi, A; Mander, B J; Porter, D E

    2009-06-01

    Primary sarcomas in the ischiorectal fossa are occasionally reported and represent a significant challenge due to the proximity of rectum, levator muscles and pudendal neurovascular structures. We report a case in which the diagnosis changed between biopsy (desmoid tumour) and resection (malignant peripheral nerve sheath tumour), requiring a multidisciplinary surgical approach involving different sub-specialties. It also illustrates the importance of undertaking sarcoma surgery in a recognized sarcoma centre with sarcoma expertise available across a range of disciplines.

  10. Engineered Herpes Simplex Viruses for the Treatment of Malignant Peripheral Nerve Sheath Tumors

    DTIC Science & Technology

    2012-09-01

    AD_________________ Award Number: W81XWH-11-1-0498 TITLE: Engineered Herpes Simplex Viruses for the...August 2012 4. TITLE AND SUBTITLE Engineered Herpes Simplex Viruses for the Treatment of Malignant Peripheral Nerve Sheath Tumors 5a. CONTRACT NUMBER...for each blot. Glyco-protein D is produced at extraordinarily high levels by our herpes simplex virus, and thus, it is quite common in herpes simplex

  11. [Malignant peripheral nerve sheath tumor with perineural differentiation (malignant perineurinoma) of the cervix uteri].

    PubMed

    Dolzhikov, A A; Mukhina, T S

    2014-01-01

    The paper describes a case of a malignant peripheral nerve sheath tumor with perineural differentiation and at the rare site of the cervix uteri in a 57-year-old patient. The diagnosis was established on the basis of extensive immunohistochemical examination, by excluding the similar neoplasms and detecting an immunophenotype characteristic of perineural differentiation. There are data available in the literature on the morphological and immunophenotypical characteristics of this tumor.

  12. Induction of malignant peripheral nerve sheath tumors in European hamsters with 1,1-dimethylhydrazine (UDMH).

    PubMed

    Ernst, H; Rittinghausen, S; Wahnschaffe, U; Mohr, U

    1987-06-01

    A rate of up to 43% of malignant peripheral nerve sheath tumors (PNST) was induced in European hamsters (EH) after weekly s.c. administration of 1,1-dimethylhydrazine (UDMH). The overall neoplastic response in the treated EH was also elevated as compared to the untreated controls. Histologically, the malignant PNST were neurofibrosarcomas and melanotic as well as unpigmented schwannomas. The occurrence of melanotic schwannomas is briefly discussed with regard to the histogenesis of this rare tumor type.

  13. How I do it: the endoscopic endonasal optic nerve and orbital apex decompression.

    PubMed

    Jacquesson, Timothée; Abouaf, Lucie; Berhouma, Moncef; Jouanneau, Emmanuel

    2014-10-01

    With the refinement of the technique, endoscopic endonasal surgery increases its field of indications. The orbital compartment is among the locations easily reached through the nostril. This anteromedial approach has been described primarily for inflammatory or traumatic diseases, with few data for tumoral diseases. Since 2010, this route has been used at our institution either for decompression or for biopsy of orbital tumoral diseases. Even if further studies are warranted, this strategy proved to be beneficial for patients, with improvements in visual outcome. In this article, the authors summarize their technique and their experience with endonasal endoscopic orbital decompression. Nasal and sphenoidal anatomies determine the feasibility and risks for doing an efficient medial optic or orbit decompression. • Techniques and tools used are those developed for pituitary surgery. • A middle turbinectomy and posterior ethmoidectomy are mandatory to expose the medial wall of the orbit. • The Onodi cell is a key marker for the optic canal and must be opened up with caution. • The lamina papyracea is opened first with a spatula and the optic canal opened up by a gentle drilling under continuous irrigation from distal to proximal. • Drilling might always be used under continuous irrigation to avoid overheating of the optic nerve. An ultrasonic device can be used as well. • The nasal corridor is narrow and instruments may hide the infrared neuronavigation probe. To overcome this issue, a magnetic device could be useful. • Doppler control could be useful to locate the ICA. • The optic canal must be opened up from the tuberculum of the sella to the orbital apex and from the planum (anterior cranial fossa) to the lateral OCR or ICA canal • At the end of the procedure, the optic nerve becomes frequently pulsatile, which is a good marker of decompression.

  14. Quantitative relationships between axoplasm and Schwann cell sheath in unmyelinated nerve fibres. An electron microscope study.

    PubMed Central

    Pannese, E; Arcidiacono, G; Frattola, D; Rigamonti, L; Procacci, P; Ledda, M

    1988-01-01

    The quantitative relationships between the size of the Schwann cell sheath and that of its related axoplasm were studied by electron microscopy in cross sections of bundles of unmyelinated axons (Remak bundles) of the spinal roots of lizard (Lacerta muralis). It was found that (i) the cross sectional area of the Schwann cell sheath is directly proportional to that of its related axoplasm (correlation coefficient 0.84), and (ii) the ratio between the cross sectional area of the Schwann cell sheath and that of its related axoplasm tends to diminish as the cross sectional area of the latter increases. Thus, under normal conditions, in the bundles of unmyelinated axons of the spinal roots of lizard a quantitative balance exists between the nerve tissue and its associated glial tissue. These results agree with those previously obtained in the myelinated fibres of the same region and in the spinal ganglia of the lizard, gecko, cat and rabbit. Some of the mechanisms probably involved in the control of the quantitative balance between nerve tissue and its associated glial tissue in peripheral nerves are listed. Images Fig. 1 PMID:3248972

  15. A Vascular Malformation Presenting as a Peripheral Nerve Sheath Tumor

    PubMed Central

    Parmar, Vikas; Haldeman, Clayton; Amaefuna, Steve; Hanna, Amgad S.

    2016-01-01

    We present the case of a venous malformation (VM) masquerading as a schwannoma. VMs are thin-walled vascular dilations of various sizes that typically present as soft, compressible, blue masses that are associated with pain or dysesthesia. VMs are commonly found in the head and neck as well as the distal extremities. Notably, slow-flow VMs are hypointense on T1-weighted imaging, hyperintense on T2-weighted imaging, and enhance markedly with contrast. However, VMs tend to be poorly circumscribed and fraught with venous lakes and phleboliths. Conservative therapy and sclerotherapy are the primary treatment options. In this case report, we present a VM presenting near the neurovascular bundle of the upper extremity axilla. Our case is unique in that the patient presented with symptoms and imaging qualities characteristic for a peripheral nerve schwannoma. PMID:28077959

  16. Suprameatal extension of retrosigmoid approach for microvascular decompression of trigeminal nerve: Case report

    PubMed Central

    Moreira-Holguin, Juan Carlos; Revuelta-Gutierrez, Rogelio; Monroy-Sosa, Alejandro; Almeida-Navarro, Samuel

    2015-01-01

    Introduction Trigeminal neuralgia is produced in a significant number of cases by vascular compression at the level of cisternal segment of the nerve at the entry of the pons. It is common to find superior cerebellar artery (SCA) responsible for this compression. The retrosigmoid approach (RA), with asterional craniectomy, clearly exposes the cisternal portion of the trigeminal nerve (TN). Presentation of case We describe in this case report how vessels at the trigeminal pore level known as “Meckel’s segment” can compress the TN. This situation is unusual. One of the reasons why the compression of this Meckel’s segment level could be overlooked is a suprameatal tubercle (ST) prominence that would prevent trigeminal pore visualization through retrosigmoid approach. Discussion The suprameatal extension of this approach has been described for other purposes, especially in tumors invading Meckel’s cave resection. We could not find publications for the use of the resection of the suprameatal tubercle in the retrosigmoid approach for microvascular decompression of the trigeminal neuralgia. Conclusion Microvascular decompression of the TN is an effective treatment for trigeminal neuralgia, however in some cases, in which vascular compression is not evident when exploring the cerebellopontine angle, it is important to note that association of a prominent ST can hide a vascular compression of the nerve in this region. PMID:26298243

  17. Facial nerve decompression surgery using bFGF-impregnated biodegradable gelatin hydrogel in patients with Bell palsy.

    PubMed

    Hato, Naohito; Nota, Jumpei; Komobuchi, Hayato; Teraoka, Masato; Yamada, Hiroyuki; Gyo, Kiyofumi; Yanagihara, Naoaki; Tabata, Yasuhiko

    2012-04-01

    Basic fibroblast growth factor (bFGF) promotes the regeneration of denervated nerves. The aim of this study was to evaluate the regeneration-facilitating effects of novel facial nerve decompression surgery using bFGF in a gelatin hydrogel in patients with severe Bell palsy. Prospective clinical study. Tertiary referral center. Twenty patients with Bell palsy after more than 2 weeks following the onset of severe paralysis were treated with the new procedure. The facial nerve was decompressed between tympanic and mastoid segments via the mastoid. A bFGF-impregnated biodegradable gelatin hydrogel was placed around the exposed nerve. Regeneration of the facial nerve was evaluated by the House-Brackmann (H-B) grading system. The outcomes were compared with the authors' previous study, which reported outcomes of the patients who underwent conventional decompression surgery (n = 58) or conservative treatment (n = 43). The complete recovery (H-B grade 1) rate of the novel surgery (75.0%) was significantly better than the rate of conventional surgery (44.8%) and conservative treatment (23.3%). Every patient in the novel decompression surgery group improved to H-B grade 2 or better even when undergone between 31 and 99 days after onset. Advantages of this decompression surgery are low risk of complications and long effective period after onset of the paralysis. To the authors' knowledge, this is the first clinical report of the efficacy of bFGF using a new drug delivery system in patients with severe Bell palsy.

  18. Altered behavioural responses and functional recovery in rats following sciatic nerve compression and early vs late decompression.

    PubMed

    Pettersson, Lina M E; Danielsen, Nils; Dahlin, Lars B

    2016-12-01

    The aim of the study was to examine sensory behaviour and functional recovery in rats during nerve compression and after decompression. Compression injury is a far more common condition than nerve transection. The condition is characterised by numbness and a tingling/burning sensation, and some patients experience pain and allodynia during compression or after decompression treatment. The aetiology is in many cases unknown. Thus, further studies are of great importance for the understanding of this condition. In the present study, behavioural responses to tactile stimulation, thermal pain, as well as functional sensorimotor behaviour were investigated in rats before, during severe compression, and after decompression. The sciatic nerve of the rats was experimentally compressed for 3 or 28 days, whereafter surgical release, i.e. decompression, of the nerve was performed and the rats were examined up to ∼9 weeks. An altered behaviour was found in response to compression injury, which is mitigated after early decompression treatment. These findings indicate that early intervention during severe compression injuries is of great importance for recovery and restoration of nerve function and, thus, should have an impact on clinical routines regarding treatment of compression injuries.

  19. Growth-associated protein 43 in differentiating peripheral nerve sheath tumors from other non-neural spindle cell neoplasms.

    PubMed

    Chen, Wei-Shen; Chen, Pei-Ling; Lu, Dongsi; Lind, Anne C; Dehner, Louis P

    2014-02-01

    The malignant peripheral nerve sheath tumor is a relatively uncommon type of soft tissue sarcoma arising from a peripheral nerve or extraneural soft tissues and showing nerve sheath differentiation. The diagnosis of malignant peripheral nerve sheath tumor is one of the most challenging tasks in surgical pathology because of its uncommon type (5-10% soft tissue sarcomas), morphologic resemblance to other spindle cell neoplasms and lack of sensitive and specific immunohistochemical markers. The pathologic diagnosis is more straightforward in the clinical setting of neurofibromatosis-1, but problems are mainly centered on the non-neurofibromatosis-1 malignant peripheral nerve sheath tumors. To date, S100 protein is the most widely applied marker in the case of a suspected malignant peripheral nerve sheath tumor, yet its suboptimal sensitivity and its expression in other spindle cell neoplasms, including spindle cell melanoma, clear-cell sarcoma, leiomyosarcoma and monophasic synovial sarcoma, add to the diagnostic conundrum. Growth-associated protein 43 (GAP43), a membrane-associated phosphoprotein expressed in neuronal growth cones and Schwann cell precursors during neural development and axonal regeneration, was applied to a set of nerve sheath and non-nerve sheath spindle cell neoplasms. The findings in this study indicate that GAP43 is expressed in malignant peripheral nerve sheath tumors (n=18/21; 86%) and demonstrates a sensitivity superior to S100 protein (n=13/21; 62%). GAP43 is also positive in neurofibromas (n=17/18; 94%), schwannomas (n=11/12; 92%) and desmoplastic melanomas (n=7/10; 70%). In contrast, it is negative in the non-desmoplastic spindle cell melanomas (n=20/22; 91%). Of the other non-neural soft tissue sarcomas, GAP43 is non-reactive in most leiomyosarcomas (n=14/16; 88%) and clear-cell sarcomas (n=8/8), and only focally positive in monophasic synovial sarcomas (n=3/7; 43%). GAP43 is seemingly a highly sensitive marker for peripheral nerve

  20. Comparison of Outside Versus Inside Brachial Plexus Sheath Injection for Ultrasound-Guided Interscalene Nerve Blocks.

    PubMed

    Maga, Joni; Missair, Andres; Visan, Alex; Kaplan, Lee; Gutierrez, Juan F; Jain, Annika R; Gebhard, Ralf E

    2016-02-01

    Ultrasound-guided interscalene brachial plexus blocks are commonly used to provide anesthesia for the shoulder and proximal upper extremity. Some reviews identify a sheath that envelops the brachial plexus as a potential tissue plane target, and current editorials in the literature highlight the need to establish precise and reproducible injection targets under ultrasound guidance. We hypothesize that an injection of a local anesthetic inside the brachial plexus sheath during ultrasound-guided interscalene nerve blocks will result in enhanced procedure success and provide a consistent tissue plane target for this approach with a reproducible and characteristic local anesthetic spread pattern. Sixty patients scheduled for shoulder surgery with a preoperative interscalene block for postoperative pain management were enrolled in this prospective randomized observer-blinded study. Each patient was randomly assigned to receive a single-shot interscalene block either inside or outside the brachial plexus sheath. The rate of complete motor and sensory blocks of the axillary nerve territory 10 minutes after local anesthetic injection for the inside group was 70% versus 37% for the outside group (P < .05). At all measurement intervals beyond 10 minutes, however, neither group showed a statistically significant difference in complete sensory blockade. The incidence rates of transient paresthesia during needle passage were 6.7% for the outside group and 96.7% for the inside group (P < .05). Except for faster onset, this prospective randomized trial did not find any advantages to performing an interscalene block inside the brachial plexus sheath. There was a higher incidence of transient paresthesia when injections were performed inside compared to outside the sheath. © 2016 by the American Institute of Ultrasound in Medicine.

  1. Malignant peripheral nerve sheath tumors of the eighth cranial nerve arising without prior irradiation.

    PubMed

    Carlson, Matthew L; Jacob, Jeffrey T; Habermann, Elizabeth B; Glasgow, Amy E; Raghunathan, Aditya; Link, Michael J

    2016-11-01

    OBJECTIVE Malignant peripheral nerve sheath tumors (MPNSTs) of the eighth cranial nerve (CN) are exceedingly rare. To date the literature has focused on MPNSTs occurring after radiation therapy for presumed benign vestibular schwannomas (VSs), while MPNSTs arising without prior irradiation have received little attention. The objectives of the current study are to characterize the epidemiology, clinical presentation, disease course, and outcome using a large national cancer registry database and a systematic review of the English literature. Additionally, a previously unreported case is presented. METHODS The authors conducted an analysis of the Surveillance, Epidemiology, and End Results (SEER) database, a systematic review of the literature, and present a case report. Data from all patients identified in the SEER database with a diagnosis of MPNST involving the eighth CN, without a history of prior radiation, were analyzed. Additionally, all cases reported in the English literature between January 1980 and March 2015 were reviewed. Finally, 1 previously unreported case is presented. RESULTS The SEER registries identified 30 cases between 1992 and 2012. The average incidence was 0.017 per 1 million persons per year (range 0.000-0.0687 per year). The median age at diagnosis was 55 years, and 16 (53%) were women. Thirteen cases were diagnosed upon autopsy. Of the 17 cases diagnosed while alive, the median follow-up was 118 days, with 3 deaths (18%) observed. When compared with the incidence of benign VS, 1041 VSs present for every 1 MPNST arising from the eighth CN. Including a previously unreported case from the authors' center, a systematic review of the English literature yielded 24 reports. The median age at diagnosis was 44 years, 50% were women, and the median tumor size at diagnosis was 3 cm. Eleven patients (46%) reported isolated audiovestibular complaints typical for VS while 13 (54%) exhibited facial paresis or other signs of a more aggressive process

  2. Metastatic Neuroendocrine Carcinoma of Unknown Origin Arising in the Femoral Nerve Sheath.

    PubMed

    Candy, Nicholas; Young, Adam; Allinson, Kieren; Carr, Oliver; McMillen, Jason; Trivedi, Rikin

    2017-08-01

    Metastatic neuroendocrine carcinoma of unknown origin is a rare condition, usually presenting with lesions in the liver and/or lung. We present the first reported case of a metastatic neuroendocrine carcinoma of unknown origin arising in the femoral nerve sheath. Magnetic resonance imaging demonstrated what was thought to be a schwannoma in the left femoral nerve sheath in the proximal femoral triangle, immediately inferior to the anterior inferior iliac spine. At the time of operation, the tumor capsule was invading surrounding tissue, as well as three trunks of the femoral nerve. The patient underwent a subtotal resection, preserving the integrity of the residual functioning femoral nerve trunks. Histologic evaluation determined that the tumor had features consistent with a metastatic neuroendocrine carcinoma of unknown primary origin. The patient recovered well postoperatively, and subsequent radiologic evaluation failed to demonstrate a potential primary site. Unfortunately, the patient re-presented with disease progression and was subsequently referred to palliative care. We recommend that there is a definite role for surgery in the management of solitary neuroendocrine carcinoma of unknown origin. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Optic nerve sheath fenestration using a Raman-shifted alexandrite laser

    PubMed Central

    Kozub, John; Shen, Jin-H.; Joos, Karen M.; Prasad, Ratna; Hutson, M. Shane

    2016-01-01

    Background and Objective Optic nerve sheath fenestration is an established procedure for relief of potentially damaging overpressure on the optic nerve resulting from idiopathic intracranial hypertension. Prior work showed that a mid-IR free-electron laser could be delivered endoscopically and used to produce an effective fenestration. This study evaluates the efficacy of fenestration using a table-top mid-IR source based on a Raman-shifted alexandrite (RSA) laser. Study Design/Materials and Methods Porcine optic nerves were ablated using light from an RSA laser at wavelengths of 6.09, 6.27 and 6.43 μm and pulse energies up to 3 mJ using both free-space and endoscopic beam delivery through 250-μm I.D. hollow-glass waveguides. Waveguide transmission was characterized, ablation thresholds and etch rates were measured, and the efficacy of endoscopic fenestration was evaluated for ex vivo exposures using both optical coherence tomography and histological analysis. Results Using endoscopic delivery, the RSA laser can effectively fenestrate porcine optic nerves. Performance was optimized at a wavelength of 6.09 μm and delivered pulse energies of 0.5-0.8 mJ (requiring 1.5-2.5 mJ to be incident on the waveguide). Under these conditions, the ablation threshold fluence was 0.8 ± 0.2 J/cm2, the ablation rate was 1-4 μm/pulse, and the margins of ablation craters showed little evidence of thermal or mechanical damage. Nonetheless, nominally identical exposures yielded highly variable ablation rates. This led to fenestrations that ranged from too deep to too shallow – either damaging the underlying optic nerve or requiring additional exposure to cut fully through the sheath. Of 48 excised nerves subjected to fenestration at 6.09 μm, 16 ex vivo fenestrations were judged as good, 23 as too deep, and 9 as too shallow. Conclusions Mid-IR pulses from the RSA laser, propagated through a flexible hollow waveguide, are capable of cutting through porcine optic nerve sheaths in

  4. Optic nerve sheath fenestration using a Raman-shifted alexandrite laser.

    PubMed

    Kozub, John; Shen, Jin H; Joos, Karen M; Prasad, Ratna; Hutson, M Shane

    2016-03-01

    Optic nerve sheath fenestration is an established procedure for relief of potentially damaging overpressure on the optic nerve resulting from idiopathic intracranial hypertension. Prior work showed that a mid-IR free-electron laser could be delivered endoscopically and used to produce an effective fenestration. This study evaluates the efficacy of fenestration using a table-top mid-IR source based on a Raman-shifted alexandrite (RSA) laser. Porcine optic nerves were ablated using light from an RSA laser at wavelengths of 6.09, 6.27, and 6.43 μm and pulse energies up to 3 mJ using both free-space and endoscopic beam delivery through 250-μm I.D. hollow-glass waveguides. Waveguide transmission was characterized, ablation thresholds and etch rates were measured, and the efficacy of endoscopic fenestration was evaluated for ex vivo exposures using both optical coherence tomography and histological analysis. Using endoscopic delivery, the RSA laser can effectively fenestrate porcine optic nerves. Performance was optimized at a wavelength of 6.09 μm and delivered pulse energies of 0.5-0.8 mJ (requiring 1.5-2.5 mJ to be incident on the waveguide). Under these conditions, the ablation threshold fluence was 0.8 ± 0.2 J/cm(2) , the ablation rate was 1-4 μm/pulse, and the margins of ablation craters showed little evidence of thermal or mechanical damage. Nonetheless, nominally identical exposures yielded highly variable ablation rates. This led to fenestrations that ranged from too deep to too shallow-either damaging the underlying optic nerve or requiring additional exposure to cut fully through the sheath. Of 48 excised nerves subjected to fenestration at 6.09 μm, 16 ex vivo fenestrations were judged as good, 23 as too deep, and 9 as too shallow. Mid-IR pulses from the RSA laser, propagated through a flexible hollow waveguide, are capable of cutting through porcine optic nerve sheaths in surgically relevant times with reasonable accuracy and low

  5. Microvascular decompression of trigeminal nerve root for treatment of a patient with hemimasticatory spasm.

    PubMed

    Dou, Ning-Ning; Zhong, Jun; Zhou, Qiu-Meng; Zhu, Jin; Wang, Yong-Nan; Li, Shi-Ting

    2014-05-01

    Hemimasticatory spasm is a rare disease; with little knowledge of the pathogenesis, it has still been intractable today. We presented a 56-year-old woman with involuntary painful spasm in her left masseter muscle for 11 years. The patient was successfully treated with microvascular decompression surgery. An offending superior cerebellar artery was found to contact with the motor branch of the trigeminal nerve root, which was then removed away and pieces of soft wadding were interposed between the nerve and the vessel to assure the separation. Postoperatively, the symptom totally disappeared and no recurrence was observed during the 7 months' follow-up. The treatment as well as the pathogenesis of the disease was reviewed, and we put forward a new hypothesis.

  6. Optic Nerve Sheath as a Novel Mechanical Load on the Globe in Ocular Duction

    PubMed Central

    Demer, Joseph L.

    2016-01-01

    Purpose The optic nerve (ON) sheath's role in limiting duction has been previously unappreciated. This study employed magnetic resonance imaging (MRI) to demonstrate this constraint on adduction. Methods High-resolution, surface coil axial MRI was obtained in 11 normal adults, 14 subjects with esotropia (ET) having normal axial length (AL) < 25.8 mm, 13 myopic subjects with ET and mean AL 29.3 ± 3.3 (SD) mm, and 7 subjects with exotropia (XT). Gaze angles and ON lengths were measured for scans employing eccentric lateral fixation in which an ON became completely straightened. Results In all groups, ON straightening occurred only in the adducting, not abducting, eye. Adduction at ON straightening was 26.0 ± 8.8° in normal subjects, not significantly different from XT at 22.2 ± 11.8°. However, there was significant increase in comparable adduction in ET to 36.3 ± 9.3°, and in myopic ET to 33.6 ± 10.7° (P < 0.04). Optic nerve length at straightening was 27.6 ± 2.7 mm in normals, not significantly different from 28.2 ± 2.8 mm in ET and 27.8 ± 2.7 mm in XT. In myopic ET, ON length at straightening was significantly reduced to 24.0 ± 2.9 mm (P < 0.002) and was associated with globe retraction in adduction, suggesting ON tethering. Conclusions Large adduction may exhaust length redundancy in the normally sinuous ON and sheath, so that additional adduction must stretch the sheath and retract or deform the globe. These mechanical effects are most significant in ET with axial myopia, but may also exert traction on the posterior sclera absent strabismus or myopia. Tethering by the ON sheath in adduction is an important, novel mechanical load on the globe. PMID:27082297

  7. Temporal Lobe Retraction Provides Better Surgical Exposure of the Peri-Geniculate Ganglion for Facial Nerve Decompression via Transmastoid Approach

    PubMed Central

    Kim, Myung Woo; Ryu, Nam Gyu; Lim, Byung Woo

    2016-01-01

    Purpose For the exposure of the labyrinthine segment of the facial nerve, transmastoid approach is not usually considered due to being situated behind the superior semicircular canal. To obtain a better view and bigger field for manipulation in the peri-geniculate area during facial nerve decompression, retraction of temporal lobe after bony removal of tegmen mastoideum was designed via transmastoid approach. Materials and Methods Fifteen patients with traumatic facial paralysis [House-Brackmann (HB) grade IV–VI], 3 patients with Bell's palsy (HB grade V–VI), and 2 patients with herpes zoster oticus (HB grade V–VI) underwent facial nerve decompression surgery between January 2008 and July 2014. In all patients, we performed temporal lobe retraction for facial nerve decompression via the transmastoid approach. Patients were examined using pre operative tests including high-resolution computed tomography, temporal magnetic resonance imaging, audiometry, and electroneurography (degenerative ratio >90%). Facial function was evaluated by HB grading scale before and 6 months after the surgery. Results After the surgery, facial function recovered to HB grade I in 9 patients and to grade II in 11 patients. No problems due to surgical retraction of the temporal lobe were noted. Compared to the standard transmastoid approach, our method helped achieve a wider surgical view for improved manipulation in the peri-geniculate ganglion in all cases. Conclusion Facial nerve decompression via the transmastoid approach with temporal lobe retraction provides better exposure to the key areas around the geniculate ganglion without complications. PMID:27593878

  8. Pulsatile Dynamics of the Optic Nerve Sheath and Intracranial Pressure: An Exploratory In Vivo Investigation

    PubMed Central

    Brekken, Reidar; Fieggen, Graham; Selbekk, Tormod

    2016-01-01

    BACKGROUND: Raised intracranial pressure (ICP) may lead to increased stiffness of the optic nerve sheath (ONS). OBJECTIVE: To develop a method for analyzing ONS dynamics from transorbital ultrasound and investigate a potential difference between patients with raised ICP vs normal ICP. METHODS: We retrospectively analyzed data from 16 patients (≤12 years old) for whom ultrasound image sequences of the ONS had been acquired from both eyes just before invasive measurement of ICP. Eight patients had an ICP ≥20 mm Hg. The transverse motion on each side of the ONS was estimated from ultrasound, and Fourier analysis was used to extract the magnitude of the displacement corresponding to the heart rate. By calculating the normalized absolute difference between the displacements on each side of the ONS, a measure of ONS deformation was obtained. This parameter was referred to as the deformability index. According to our hypothesis, because deformability is inversely related to stiffness, we expected this parameter to be lower for ICP ≥20 mm Hg compared with ICP <20 mm Hg. The one-sided Mann-Whitney U test was used for statistical comparison. RESULTS: The deformability index was significantly lower in the group with ICP ≥20 mm Hg (median value 0.11 vs 0.24; P = .002). CONCLUSION: We present a method for assessment of ONS pulsatile dynamics using transorbital ultrasound imaging. A significant difference was noted between the patient groups, indicating that deformability of the ONS may be relevant as a noninvasive marker of raised ICP. The clinical implications are promising and should be investigated in future clinical studies. ABBREVIATIONS: AUC, area under curve ICP, intracranial pressure ONS, optic nerve sheath ONSD, optic nerve sheath diameter ROC, receiver operating characteristic PMID:26813857

  9. Alterations of oxidative phosphorylation in meningiomas and peripheral nerve sheath tumors.

    PubMed

    Feichtinger, René G; Weis, Serge; Mayr, Johannes A; Zimmermann, Franz A; Bogner, Barbara; Sperl, Wolfgang; Kofler, Barbara

    2016-02-01

    Changes in the mode of aerobic energy production are observed in many solid tumors, though the kinds of changes differ among tumor types. We investigated mitochondrial energy metabolism in meningiomas and peripheral nerve sheath tumors, taking into consideration the histologic heterogeneity of these tumors. Oxidative phosphorylation (OXPHOS) complexes and porin (a marker for mitochondrial mass) were analyzed by immunohistochemical staining of meningiomas (n = 76) and peripheral nerve sheath tumors (schwannomas: n = 10; neurofibromas: n = 4). The enzymatic activities of OXPHOS complexes and citrate synthase were determined by spectrophotometric measurement. Western blot analysis of OXPHOS complexes, porin, and mitochondrial transcription factor A was performed. Furthermore, mitochondrial DNA copy number was determined. The tumors differed with regard to mitochondrial energy metabolism. Low levels of a subset of OXPHOS complexes were frequently observed in World Health Organization grade I meningiomas (percent of cases with a reduction; complex I: 63%; complex II: 67%; complex IV: 56%) and schwannomas (complex III: 40%, complex IV: 100%), whereas in neurofibromas a general reduction of all complexes was observed. In contrast, expression of complexes III and V was similar to that in normal brain tissue in the majority of tumors. Mitochondrial mass was comparable or higher in all tumors compared with normal brain tissue, whereas mitochondrial DNA copy number was reduced. The reduction of OXPHOS complexes in meningiomas and peripheral nerve sheath tumors has potential therapeutic implications, since respiratory chain-deficient tumor cells might be selectively starved by inhibitors of glycolysis or by ketogenic diet. © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  10. Optic nerve sheath meningioma detected by single- photon emission computed tomography/computed tomography somatostatin receptor scintigraphy: a case report.

    PubMed

    Nussbaum-Hermassi, Lucie; Ahle, Guido; Zaenker, Chistophe; Duca, Camelia; Namer, Izzie Jacques

    2016-04-22

    Optic nerve sheath meningiomas account for only 2% of orbital lesions and 42% of optic nerve tumors. Diagnosis remains difficult because histologic confirmation carries a high risk of visual loss. Therefore, a less invasive and specific diagnostic method for differentiating optic nerve sheath meningiomas from other optic nerve lesions is needed to overcome the limitations of computed tomography and magnetic resonance imaging, and make the best individualized treatment decision. This case is a good illustration of the clinical and imaging difficulties inherent in this rare tumor, which may be hard to differentiate from other causes. A 51-year-old Caucasian woman developed a central scotoma, visual loss, and abnormal visual evoked potentials. The first magnetic resonance imaging scan classified the optic nerve damage as retrobulbar optic neuritis. After magnetic resonance imaging follow-up at 3 months, a negative lumbar puncture and biological workup, and clinical worsening, an optic nerve sheath meningioma was suspected. We confirmed this diagnosis with 111In-pentetreotide single-photon emission computed tomography, which is able to bind with very high affinity to somatostatin receptor subtype 2 expressed on meningiomas. In the diagnosis of optic nerve sheath meningiomas, [111In]-pentetreotide single-photon emission computed tomography-fused magnetic resonance imaging is a valuable additional tool, optimizing the diagnosis and obviating the need for a more invasive procedure.

  11. Malignant peripheral nerve sheath tumour (MPNST) of mandible: solving the perplexity.

    PubMed

    Patel, Shilpa; Pathak, Jigna; Dekate, Kamlesh; Mohanty, Neeta

    2015-03-11

    We present an extremely rare case of malignant peripheral nerve sheath tumour (MPNST) in a 30-year-old woman without associated neurofibromatosis 1. The patient presented with an 8 cm×4 cm lesion extending from 46 to the retro molar region involving the ramus of the right mandible associated with regional paraesthesia. Incisional biopsy revealed spindle cells with vesicular nuclei arranged in fascicles leading to a diagnosis of spindle cell lesion. Posterior segmental mandibulectomy was performed under general anaesthesia. On excisional biopsy, a definitive diagnosis of low-grade MPNST was established on the basis of immunohistochemistry. The patient was then lost to follow-up.

  12. Potential of boron neutron capture therapy (BNCT) for malignant peripheral nerve sheath tumors (MPNST).

    PubMed

    Fujimoto, Takuya; Andoh, Tooru; Sudo, Tamotsu; Fujita, Ikuo; Fukase, Naomasa; Takeuchi, Tamotsu; Sonobe, Hiroshi; Inoue, Masayoshi; Hirose, Tkanori; Sakuma, Toshiko; Moritake, Hiroshi; Sugimoto, Tohru; Kawamoto, Teruya; Fukumori, Yoshinobu; Yamamoto, Satomi; Atagi, Shinji; Sakurai, Yoshinori; Kurosaka, Masahiro; Ono, Koji; Ichikawa, Hideki; Suzuki, Minoru

    2015-12-01

    Malignant peripheral nerve sheath tumors (MPNST) are relatively rare neoplasms with poor prognosis. At present there is no effective treatment for MPNST other than surgical resection. Nonetheless, the anti-tumor effect of boron neutron capture therapy (BNCT) was recently demonstrated in two patients with MPNST. Subsequently, tumor-bearing nude mice subcutaneously transplanted with a human MPNST cell line were injected with p-borono-L-phenylalanine (L-BPA) and subjected to BNCT. Pathological studies then revealed that the MPNST cells were selectively destroyed by BNCT.

  13. Optic Nerve Sheath Diameter Ultrasound and the Diagnosis of Increased Intracranial Pressure.

    PubMed

    Hylkema, Christopher

    2016-03-01

    Ultrasound has been used for almost 30 years in a wide variety of clinical applications and environments. From the austerity of battlefields to the labor and delivery ward, ultrasound has the ability to give clinicians real-time, noninvasive diagnostic imaging. Ultrasound by emergency physicians (and all nonradiologists) has become more prevalent and has been used for examinations such as the transcranial Doppler to evaluate for stroke, cardiac function, FAST and EFAST examinations for trauma, and now increased intracranial pressure (ICP) via Optic Nerve Sheath Diameter Ultrasound (ONSD). The ONSD is a valid and reliable indicator of ICP.

  14. Giant Sporadic Low Grade Malignant Peripheral Nerve Sheath (MPNST) of Left Thigh.

    PubMed

    Nikumbh, Dhiraj B; Suryawanshi, K H; Dravid, N V; Patil, T B; Rokade, C M

    2013-06-01

    Malignant Peripheral Nerve Sheath Tumours (MPNST) are rare spindle- cell sarcomas which are derived from the schwann cells or the pleuripotent cells of the neural crest. MPNSTs are usually located in the peripheral nerve trunk roots, extremities and in the head and neck region. These tumours may arise as sporadic variants or in patients with neurofibromatosis1 (NF1). The estimated incidence of MPNSTs in the patients with NF1is 2-5% as compared to a 0.001% incidence in the general population. Herein, we are reporting a case of a giant sporadic (NF1 independent) low grade MPNST of the left thigh in 65 year female patient, which had a good prognosis.

  15. Composite phaeochromocytoma with malignant peripheral nerve sheath tumour and rhabdomyosarcomatous differentiation in a patient without von Recklinghausen disease.

    PubMed

    Gupta, R; Sharma, A; Arora, R; Vijayaraghavan, M

    2009-07-01

    The coexistence of adrenal phaeochromocytoma with non-chromaffin tumours is a rare fascinating occurrence. This category of tumours is subdivided into "composite" and "mixed". The coexistence of adrenal phaeochromocytoma with a malignant Triton tumour does not appear to have been described in the available literature so far. A unique case of composite phaeochromocytoma in a 26-year-old male patient, where the non-chromaffin component was a malignant Triton tumour composed of peripheral nerve sheath tumour and skeletal muscle differentiation, is reported. This admixture was confirmed with immunohistochemical pattern of expression. This is the first case of such a phenomenon in a composite phaeochromocytoma. The present case further widens the histomorphological range of composite phaeochromocytoma of the adrenal gland, which the histopathologist should be aware of. Since the prognosis of composite phaeochromocytoma with malignant nerve sheath tumour would be determined by the nerve sheath component, recognition of this tumour is imperative.

  16. Effects of pigment epithelium derived factor (PEDF) on malignant peripheral nerve sheath tumours (MPNSTs).

    PubMed

    Demestre, Maria; Terzi, Menderes Yusuf; Mautner, Victor; Vajkoczy, Peter; Kurtz, Andreas; Piña, Ana Luisa

    2013-12-01

    Neurofibromatosis type 1 (NF1) is an inherited genetic disease affecting 1 in 3,500 individuals. A prominent feature of NF1 is the formation of benign tumours of the peripheral nerve sheath (neurofibromas). However, these can become malignant and form highly metastatic malignant peripheral nerve sheath tumours (MPNST), which are usually fatal despite aggressive surgery, chemotherapy, and radiotherapy. Recent studies have shown that pigment epithelium-derived factor (PEDF) can induce differentiation and inhibit angiogenesis in several kinds of tumours. The present study was designed to determine the in vitro and in vivo effects of PEDF on MPNST angiogenesis and tumour growth. PEDF inhibited proliferation and augmented apoptosis in S462 MPNST cells after 48 h of treatment in culture. In xenografts of S462 MPNST cells in athymic nude mice, PEDF suppressed MPNST tumour burden, due mainly to inhibition of angiogenesis. These results demonstrate for the first time inhibitory effects of PEDF on the growth of human MPNST via induction of anti-angiogenesis and apoptosis. Our results suggest that PEDF could be a novel approach for future therapeutic purposes against MPNST.

  17. Feline peripheral nerve sheath tumors: histologic, immunohistochemical, and clinicopathologic correlation (59 tumors in 53 cats).

    PubMed

    Schulman, F Y; Johnson, T O; Facemire, P R; Fanburg-Smith, J C

    2009-11-01

    Feline peripheral nerve sheath tumors are uncommonly reported, and their clinical behavior has not been well documented. Fifty-nine peripheral nerve sheath tumors were collected from 53 cats. All of the tumors involved skin, subcutis, skeletal muscle, and/or mucous membranes. Histologically, the tumors were composed of compact to loosely arranged streams and fascicles of spindled cells with eosinophilic, often wavy cytoplasmic processes; small to occasionally moderate amounts of collagenous to myxoid matrix; and nuclear palisading. Immunohistochemically, all tumors were positive for vimentin and S-100 protein, 44 of 59 were positive for glial fibrillary acidic protein (GFAP), and all were negative for muscle specific actin. The tumors fell into 3 histologic categories: 34 benign tumors with Antoni A areas that were S-100 protein and GFAP positive, 9 benign tumors that lacked Antoni A areas and were S-100 protein positive and GFAP negative, and 16 tumors with features of malignancy. Seventy-five percent of these cases involved the head, neck, or limbs. Recurrent tumors were submitted or tumors were reported to have recurred in 9 cases. Tumor recurrence was reported for all 3 of the histologic subtypes. None was documented as having metastasized.

  18. Breast metastases from a malignant peripheral nerve sheath tumor of the kidney: An unusual presentation

    PubMed Central

    Koppisetty, Shalini; Alessio, Ricardo C.; Rajpurkar, Atul

    2016-01-01

    Malignant peripheral nerve sheath tumors (MPNSTs) are extremely rare soft tissue sarcomas of ectomesenchymal origin. They are commonly seen in association with neurofibromatosis type 1 (NF-1), but can also occur without a history of NF (isolated MPNST). MPNSTs are most commonly located on the extremities (brachial and sacral plexus), head and neck, and trunk regions and are rarely reported in genitourinary organs. These tumors are aggressive, with a high recurrence rate and distant metastases. MPNST involving the kidney is extremely rare, and review of the literature using PubMed from 2001 to 2014 revealed eight cases of MPNST involving the kidney (seven, primarily involving the kidney and one metastatic MPNST of the kidney). Herein, we describe a case of breast metastases from an MPNST of the kidney without a history of NF-1. The patient was initially diagnosed with a spindle cell neoplasm of the kidney with peripheral nerve sheath differentiation. Eventually, the patient developed a right breast mass that was diagnosed as metastatic MPNST. The patient refused any kind of treatment and died 6 months later in hospice care. PMID:27453670

  19. Diffusion tensor tractography for the surgical management of peripheral nerve sheath tumors.

    PubMed

    Schmidt, Manfred; Kasprian, Gregor; Amann, Gabriele; Duscher, Dominik; Aszmann, Oskar C

    2015-09-01

    OBJECT Peripheral nerve sheath tumors (PNSTs) are uncommon but bear a significant risk of malignancy. High-resolution MRI is the standard technique for characterizing PNSTs. However, planning the appropriate extent of resection and subsequent reconstructive strategies is highly dependent on the intraoperative findings because preoperative MRI evaluation can be insufficient. Diffusion tensor tractography (DTT) represents a recently developed advanced MRI technique that reveals the microstructure of tissues based on monitoring the random movement of water molecules. DTT has the potential to provide diagnostic insights beyond conventional MRI techniques due to its mapping of specific fibrillar nerve structures. Here, DTT was applied to evaluate PNSTs and to examine the usefulness of this method for the correct delineation of tumor and healthy nerve tissue and the value of this information in the preoperative planning of surgical interventions. METHODS In this prospective study, patients with the clinical symptoms of a PNST were investigated using DTT 3-Tesla MRI scans. Image data processing and tractography were performed using the FACT (fiber assessment by continuous tracking) algorithm and multiple-regions-of-interest approach. The surgical findings were then compared with the results of the DTT MRI scans. Preoperative fascicle visualization and the correlation with the intraoperative findings were graded. RESULTS In a 21-month period, 12 patients with PNSTs were investigated (7 female and 5 male patients with a mean age of 46.2 ± 19.2 years). All patients underwent surgical removal of the tumor. Schwannoma was the most common benign histopathological finding (n = 7), whereas 2 malignant lesions were detected. In 10 of 12 patients, good preoperative nerve fascicle visualization was achieved using DTT scans. In 9 of 10 patients with good preoperative fascicle visualization, good intraoperative correlation between the DTT scans and surgical anatomy was found

  20. Successful inferior alveolar nerve decompression for dysesthesia following endodontic treatment: report of 4 cases treated by mandibular sagittal osteotomy.

    PubMed

    Scolozzi, Paolo; Lombardi, Tommaso; Jaques, Bertrand

    2004-05-01

    Endodontic overfilling involving the mandibular canal may cause an injury of the inferior alveolar nerve (IAN) resulting in disabling sensory disturbances such as pain, dysesthesia, paresthesia, hypoesthesia, or anesthesia. Two fundamental mechanisms are responsible for the injury: the chemical neurotoxicity and the mechanical compression caused by the extruded material. Although spontaneous resorption has been described for some materials, early surgical exploration with removal of the material and decompression of the IAN should be performed, irrespective of the material used, given that the importance of nerve damage increases with the duration of the injury. We report 4 cases of disabling dysesthesia and paresthesia following endodontic treatment of lower molars in which sagittal osteotomy was used to remove the endodontic paste and to perform nerve decompression. All the patients experienced immediate relief of dysesthesia and paresthesia.

  1. [Ultrasonographic measurement of the optical nerve sheath for the diagnosis of intracranial hypertension in the emergency room : a case report].

    PubMed

    Levy, R; Kerzmann, B; Franssen, V; Schwab, A S; Adam, J F; Sottiaux, Th

    2016-06-01

    Early diagnosis and treatment of intracranial hypertension (ICHT) are major components of the management of neurological emergencies. The optic nerve sheath diameter is closely dependent on intracranial pressure and can be measured by bedside ultrasound (US). We report the story of a 70-year-old COPD patient initially admitted to the emergency room for a sepsis of pulmonary origin. An unusual confusion prompted us to perform an US of the optic nerve sheath. This exam clearly suggested the presence of an ICHT. Hence, the diagnostic approach was proceeded and a herpetic encephalitis was demonstrated and successfully treated. In this clinical report, the optic nerve sheath US guided the diagnostic approach and, eventually, therapeutic decision. Several papers have shown the close relationship between increased optic nerve sheath diameter and intracranial hypertension, but we still need further studies to validate a threshold value of this diameter. The clinical relevance of the US optic nerve diameter measure appears interesting. However, further studies on larger samples of patients are needed to confirm this and to establish a validated threshold value.

  2. Optic nerve sheath diameter measurements by CT scan in ventriculoperitoneal shunt obstruction.

    PubMed

    Zaidi, Syed Javed H; Yamamoto, Loren G

    2014-08-01

    The objective of the study was to determine differences in optic nerve sheath diameter (ONSD) measurements taken from computed tomography (CT) scans of patients with ventriculoperitoneal shunt (VPS) obstruction versus controls. Inpatients 0-15 years with confirmed VPS obstruction requiring neurosurgical intervention were identified using ICD9 codes. ONSDs, orbit, cranium, and foramen magnum sizes were measured on their pre-surgical CT. Controls included cases at times when their VPS was not obstructed and age and gender matched patients with a CT scan done in the emergency room for head trauma (normal CT findings). Paired T-tests were used for both case-control comparisons. In order to compare the optic nerve sheath size more accurately, the ONSD width was divided by the width of the orbit and by the foramen magnum (antero-posterior) length. Twenty patients were identified with 25 events of VPS obstruction. The right ONSD (RON) was chosen to study. RON/orbit width and RON/foramen magnum diameter for the VPS obstruction versus self-controls, were 0.22 and 0.22, compared to 0.19 and 0.18, respectively, for the non-obstructed self-controls (P = .044 and P = .008, respectively). The same measurements for the VPS obstruction versus age and gender matched controls were 0.22 and 0.21 for the VPS obstruction cases, respectively, compared to 0.17 and 0.16, respectively for the age and gender matched controls (P < .001 and P < .001, respectively). This data confirms that the optic nerve diameter increases during a VPS obstruction. ONSD measurements by ultrasound could add to the evaluation for VPS obstruction.

  3. Visual outcome after fronto-temporo-orbito-zygomatic approach combined with early extradural and intradural optic nerve decompression in tuberculum and diaphragma sellae meningiomas.

    PubMed

    Mortini, Pietro; Barzaghi, Lina Raffaella; Serra, Carlo; Orlandi, Vittoria; Bianchi, Stefania; Losa, Marco

    2012-07-01

    The surgical challenge of the treatment of tuberculum (TSMs) and diaphragma sellae meningiomas (DSMs) is to preserve or improve the visual function. Extradural and intradural optic nerve decompression should reduce surgical trauma of the nerve achieving a good visual result. We reported 37 consecutive TSMs and DSMs operated through fronto-temporo-orbito-zygomatic approach with extradural unroofing of the optical canal and early intradural incision of the dural sheath. Visual data were recorded measuring the visual impairment score (VIS), the visual acuity (VA), the visual field (VF) and the postoperative improvement. A good visual outcome (VIS improved or unchanged) was obtained in 97.2% of patients (35/36). The evaluation of 72 eyes showed a good outcome (VA and VF unchanged or improved) in 98.6% (71/72 eyes). The degree of preoperative VA and VF impairment was the only factor correlating with the postoperative improvement of VA (P<.001 and P=.018) and VF defect (P<.001). Worsening of visual function occurred in 1/37 patient (2.7%). Using this surgical technique we achieved a high improvement rate of visual defects and a low frequency of worsening. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. Ultrasound imaging of the median nerve as a prognostic factor for carpal tunnel decompression.

    PubMed

    Bland, Jeremy D P; Rudolfer, Stephan M

    2014-05-01

    The diagnostic value of ultrasound imaging in carpal tunnel syndrome is established, but reports on its prognostic value have been contradictory. This investigation was an observational study of subjective surgical results, evaluated by symptom severity and functional status scales, and an ordinal scale for overall outcome, for 145 carpal tunnel decompressions in relation to preoperative measurement of median nerve cross-sectional area. The surgical success rate was 86%. In univariate analyses no significant correlation existed between outcome and preoperative cross-sectional area, nor with preoperative nerve conduction studies or patient variables, except for body mass index and gender. A multivariate model including electrophysiological, imaging, and patient variables was moderately predictive of success with an area under the receiver operating characteristic curve of 0.82. Cross-sectional area alone is unlikely to be a sufficiently reliable predictor of outcome for use in counseling individual patients, but imaging results may be useful in multivariate prognostic models. Copyright © 2013 Wiley Periodicals, Inc.

  5. Malignant nerve-sheath neoplasms in neurofibromatosis: distinction from benign tumors by using imaging techniques

    SciTech Connect

    Levine, E.; Huntrakoon, M.; Wetzel, L.H.

    1987-11-01

    Malignant peripheral nerve-sheath neoplasms frequently complicate neurofibromatosis causing pain, enlarging masses, or neurologic deficits. However, similar findings sometimes also occur with benign nerve neoplasms. Our study was done retrospectively to determine if imaging techniques can differentiate malignant from benign nerve tumors in neurofibromatosis. Eight patients with symptomatic neoplasms (three benign, five malignant) were studied by CT in eight, MR in six, and /sup 67/Ga-citrate scintigraphy in seven. Uptake of /sup 67/Ga occurred in all five malignant lesions but not in two benign neoplasms studied. On CT or MR, all eight lesions, including three benign neoplasms, showed inhomogeneities. Of five lesions with irregular, infiltrative margins on CT or MR, four were malignant and one was benign. Of three lesions with smooth margins, one was malignant and two were benign. One malignant neoplasm caused irregular bone destruction. Accordingly, CT and MR could not generally distinguish malignant from benign lesions with certainty. However, both CT and MR provided structural delineation to help surgical planning for both types of lesion. /sup 67/Ga scintigraphy appears promising as a screening technique to identify lesions with malignant degeneration in patients with neurofibromatosis. Any area of abnormal radiogallium uptake suggests malignancy warranting further evaluation by CT or MR. Biopsy of any questionable lesion is essential.

  6. Magnetic resonance imaging characteristics of peripheral nerve sheath tumors of the canine brachial plexus in 18 dogs.

    PubMed

    Kraft, Susan; Ehrhart, E J; Gall, David; Klopp, Lisa; Gavin, Patrick; Tucker, Russ; Bagley, Rod; Kippenes, Hege; DeHaan, Constance; Pedroia, Vince; Partington, Beth; Olby, Natasha

    2007-01-01

    Magnetic resonance imaging (MRI) examinations from 18 dogs with a histologically confirmed peripheral nerve sheath tumor (PNST) of the brachial plexus were assessed retrospectively. Almost half (8/18) had a diffuse thickening of the brachial plexus nerve(s), six of which extended into the vertebral canal. The other 10/18 dogs had a nodule or mass in the axilla (1.2-338 cm3). Seven of those 10 masses also had diffuse nerve sheath thickening, three of which extended into the vertebral canal. The majority of tumors were hyperintense to muscle on T2-weighted images and isointense on T1-weighted images. Eight of 18 PNSTs had only minimal to mild contrast enhancement and many (13/18) enhanced heterogeneously following gadolinium DTPA administration. Transverse plane images with a large enough field of view (FOV) to include both axillae and the vertebral canal were essential, allowing in-slice comparison to detect lesions by asymmetry of structures. Higher resolution, smaller FOV, multiplanar examination of the cervicothoracic spine was important for appreciating nerve root and foraminal involvement. Short tau inversion recovery, T2-weighted, pre and postcontrast T1-weighted pulse sequences were all useful. Contrast enhancement was critical to detecting subtle diffuse nerve sheath involvement or small isointense nodules, and for accurately identifying the full extent of disease. Some canine brachial plexus tumors can be challenging to detect, requiring a rigorous multiplanar multi-pulse sequence MRI examination.

  7. Malignant peripheral nerve sheath tumor of the third eyelid in a 3-year-old Rhodesian Ridgeback

    PubMed Central

    vom Hagen, Franziska; Romkes, Gwendolyna; Kershaw, Olivia; Eule, J Corinna

    2015-01-01

    Key Clinical Message A 3-year-old Rhodesian Ridgeback was presented with conjunctivitis, enlargement of the third eyelid and a dorsotemporal deviation of the right eye. A mass within the third eyelid was detected and excised. The histopathologic examination showed a malignant peripheral nerve sheath tumor, which most likely is a neurofibrosarcoma based on immunohistochemistry. PMID:25678975

  8. Ultrasound-guided fine needle aspiration in the diagnosis of peripheral nerve sheath tumors in 4 dogs

    PubMed Central

    da Costa, Ronaldo C.; Parent, Joane M.; Dobson, Howard; Ruotsalo, Kristiina; Holmberg, David; Duque, M. Carolina; Poma, Roberto

    2008-01-01

    Ultrasound-guided fine needle aspiration was used in establishing the diagnosis in 4 cases of malignant peripheral nerve sheath tumor. Sonographic and cytologic characteristics are discussed. Because of its availability and ease of use, axillary ultrasonography with fine needle aspiration can be an initial diagnostic step for suspected brachial plexus tumors. PMID:18320983

  9. Convection-Enhanced Delivery (CED) in an Animal Model of Malignant Peripheral Nerve Sheath (MPNST) Tumors and Plexiform Neurofibromas (PN)

    DTIC Science & Technology

    2012-09-01

    convection enhanced delivery in malignant peripheral nerve sheath tumors or plexiform neurofibromas at this time. References Perrin GQ, Fishbein L...2007. 85(6): p. 1347-1357. Perrin GQ, Li H, Fishbein L, et al., An orthotopic xenograft model of intraneural NF1 MPNST suggests a potential

  10. Primary peripheral nerve sheath tumors of the thyroid gland: A case report and literature review

    PubMed Central

    CHEN, GUANG; LIU, ZENGGUANG; SU, CHANG; GUAN, QIANG; WAN, FANG; DONG, BINGFEI; BAO, LIANG; ZHANG, WENXIN; WANG, YINPING; WANG, GUIMIN

    2016-01-01

    Primary peripheral nerve sheath tumors (PNSTs) of the thyroid gland are rare, with fewer than 30 cases reported in the medical literature to date. Primary PNSTs of the thyroid gland are classified into malignant and benign PNSTs. The benign PNSTs may be further subclassified into neurofibromas and Schwannomas. This is the case report of a 51-year-old male patient presenting with multiple primary PNSTs involving the left lobe of the thyroid gland. The patient underwent total excision of the thyroid gland and the pathological results indicated a Schwannoma with Antoni type A and B cells. The literature was reviewed briefly and, to the best of our knowledge, this is the first case report of multiple primary PNSTs of the thyroid gland. PMID:26893864

  11. A Case of Hypertensive Encephalopathy with Enlarged Optic Nerve Sheath Measured by Transorbital Sonography.

    PubMed

    Kitano, Takaya; Nezu, Tomohisa; Mukai, Tomoya; Uemura, Jyunichi; Wada, Yuko; Yagita, Yoshiki

    2017-01-01

    This case report describes our experience in using transorbital sonography to evaluate pathological changes in the central nervous system in hypertensive encephalopathy. A 49-year-old man with nausea, headache, and mild confusion was diagnosed with hypertensive encephalopathy by brain magnetic resonance imaging (MRI), which revealed vasogenic edema in the bilateral thalamus and the brain stem. Lumbar puncture showed no severe intracranial hypertension. Transorbital sonography showed an increase in the optic nerve sheath diameter (ONSD). Repeated examination revealed a return of the ONSD to an almost normal range after a reduction in blood pressure and a resolution of symptoms. An improvement in cerebral vasogenic edema was confirmed by brain MRI. ONSD might be related to the severity of cerebral vasogenic edema. Repeated measurement of ONSD by transorbital sonography may be useful to assess the pathological course and the effect of treatment in hypertensive encephalopathy. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  12. Primary peripheral nerve sheath tumors of the thyroid gland: A case report and literature review.

    PubMed

    Chen, Guang; Liu, Zengguang; Su, Chang; Guan, Qiang; Wan, Fang; Dong, Bingfei; Bao, Liang; Zhang, Wenxin; Wang, Yinping; Wang, Guimin

    2016-02-01

    Primary peripheral nerve sheath tumors (PNSTs) of the thyroid gland are rare, with fewer than 30 cases reported in the medical literature to date. Primary PNSTs of the thyroid gland are classified into malignant and benign PNSTs. The benign PNSTs may be further subclassified into neurofibromas and Schwannomas. This is the case report of a 51-year-old male patient presenting with multiple primary PNSTs involving the left lobe of the thyroid gland. The patient underwent total excision of the thyroid gland and the pathological results indicated a Schwannoma with Antoni type A and B cells. The literature was reviewed briefly and, to the best of our knowledge, this is the first case report of multiple primary PNSTs of the thyroid gland.

  13. BNIP3 regulates AT101 [(-)-gossypol] induced death in malignant peripheral nerve sheath tumor cells.

    PubMed

    Kaza, Niroop; Kohli, Latika; Graham, Christopher D; Klocke, Barbara J; Carroll, Steven L; Roth, Kevin A

    2014-01-01

    Malignant peripheral nerve sheath tumors (MPNSTs) are aggressive Schwann cell-derived sarcomas and are the leading cause of mortality in patients with neurofibromatosis type 1 (NF1). Current treatment modalities have been largely ineffective, resulting in a high rate of MPNST recurrence and poor five-year patient survival. This necessitates the exploration of alternative chemotherapeutic options for MPNST patients. This study sought to assess the cytotoxic effect of the BH3-mimetic AT101 [(-)-gossypol] on MPNST cells in vitro and to identify key regulators of AT101-induced MPNST cell death. We found that AT101 caused caspase-independent, non-apoptotic MPNST cell death, which was accompanied by autophagy and was mediated through HIF-1α induced expression of the atypical BH3-only protein BNIP3. These effects were mediated by intracellular iron chelation, a previously unreported mechanism of AT101 cytotoxicity.

  14. Synchronous Malignant Peripheral Nerve Sheath Tumor and Adenocarcinoma of the Prostate: Case Report and Literature Review

    PubMed Central

    Bouropoulos, Konstantinos; Farmakis, Antonios

    2016-01-01

    Malignant Peripheral Nerve Sheath Tumors (MPNSTs) of the prostate are extremely rare. A very unusual case of simultaneous adenocarcinoma and MPNST of the prostate is reported. A 60-year-old Caucasian male presented for annual urologic examination. Digital rectal examination revealed a painless, toughish, and asymmetrically enlarged prostate. Serum prostate-specific antigen was 1 ng/mL. Radiologic examinations demonstrated a large mass, which was arising from the left peripheral lobe of the prostate. The patient underwent transrectal ultrasound-guided biopsy of the prostate which revealed a smooth muscle tumor of uncertain malignant potential. Radical retropubic prostatectomy with en bloc removal of the mass and the seminal vesicles was performed and histology demonstrated low-grade MPNST and adenocarcinoma of the prostate. To the best of our knowledge, this is the first report of simultaneous prostatic adenocarcinoma and MPNST in the English literature. PMID:27872787

  15. Malignant Peripheral Nerve Sheath Tumor of Prostate: A Rare Case Report and Literature Review

    PubMed Central

    Lu, Chih-Cheng; Li, Chien-Feng

    2016-01-01

    A mid-aged male presented with progressive lower urinary tract symptoms (LUTS) for years. Huge prostate with low serum prostate-specific antigen (PSA) level was detected. The specimen from transurethral resection revealed surprising pathology finding as malignant peripheral nerve sheath tumor (MPNST). Considering its huge size (more than 300 gm) and location, we prescribed neoadjuvant chemotherapy firstly. The tumor became regressive and then radical surgical resection was achieved. Adjuvant multimodality treatment including concurrent chemoradiotherapy (CCRT) and target therapy was given. However, he expired about one year later. MPNST originating from prostate is very rare and seldom reported before. We here present this extremely rare disease and share our treatment experience. PMID:27872789

  16. Epigenetic mechanisms drive the progression of neurofibromas to malignant peripheral nerve sheath tumors

    PubMed Central

    Suresh, Krish; Kliot, Tamara; Piunti, Andrea; Kliot, Michel

    2016-01-01

    Thinking Outside the Box: The polycomb repressive complex 2 (PRC2) is a histone methyltransferase complex known to repress gene expression. There is a large body of experimental evidence that supports its role in promoting tumorigenicity by suppressing tumor suppressor genes. Here, we discuss the surprising findings that, in neurofibromas, it may have a completely different role as a tumor suppressor; mutations of PRC2 lead to conversion of benign neurofibromas into malignant peripheral nerve sheath tumors (MPNSTs) by de-repressing and thereby activating genes driving cell growth and development. These findings have potentially powerful clinical applications in both diagnosing and treating MPNSTs. Hypothesis: PRC2 loss drives malignant transformation of neurofibromas. PMID:27920939

  17. Optic Nerve Sheath Diameter: Translating a Terrestrial Focused Technique into a Clinical Monitoring Tool for Spaceflight

    NASA Technical Reports Server (NTRS)

    Mason, Sara; Foy, Millennia; Sargsyan, Ashot; Garcia, Kathleen; Wear, Mary L.; Bedi, Deepak; Ernst, Randy; Van Baalen, Mary

    2015-01-01

    Ultrasonography is increasingly used to quickly measure optic nerve sheath diameter (ONSD) when increased intracranial pressure (ICP) is suspected. NASA Space and Clinical Operations Division has been using ground and on-orbit ultrasound since 2009 as a proxy for ICP in non-acute monitoring for space medicine purposes. In the terrestrial emergency room population, an ONSD greater than 0.59 cm is considered highly predictive of elevated intracranial pressure. However, this cut-off limit is not applicable to the spaceflight setting since over 50% of US Operating Segment (USOS) astronauts have an ONSD greater than 0.60 cm even before launch. Crew Surgeon clinical decision-making is complicated by the fact that many astronauts have history of previous spaceflights. Our data characterize the distribution of baseline ONSD in the astronaut corps, its longitudinal trends in long-duration spaceflight, and the predictive power of this measure related to increased ICP outcomes.

  18. A huge malignant peripheral nerve sheath tumor with hepatic metastasis arising from retroperitoneal ganglioneuroma.

    PubMed

    Meng, Z H; Yang, Y S; Cheng, K L; Chen, G Q; Wang, L P; Li, W

    2013-01-01

    Ganglioneuromas (GNs) are the rarest and most benign of the neuroblastic tumors. We experienced a case of huge retroperitoneal GN which differentiated into malignant peripheral nerve sheath tumors (MPNST) with hepatic metastasis. The tumor was located in the upper right quarter of the abdomen and pressed the right lobe of the liver, which was initially misdiagnosed as a liver carcinoma. The tumor shared blood supply with the right liver lob and had rich blood supplies from the abdominal aorta, renal artery and hepatic artery. It was also associated with skin pigment and recurrence shortly following resection. Our finding demonstrated that MPNST is a potent invasive malignant tumor and metastasis earlier with very poor prognosis.

  19. An atypical peripheral nerve sheath tumour with pseudoglandular architecture in a dog.

    PubMed

    Volmer, Christelle; Caplier, Laura; Reyes-Gomez, Edouard; Huet, Hélène; Owen, Roger A; Fontaine, Jean-Jacques

    2010-02-01

    This case describes a subcutaneous soft tissue tumour in a German Shepherd dog. Histologically, the lesion was characterized by proliferating ovoid cells, loosely arranged in a collagenous to myxoid stroma, and by numerous pseudoglandular structures lined by neoplastic cells. Immunohistochemically, neoplastic cells were labelled with vimentin, glial fibrillary acidic protein and S100 antibodies, but not with cytokeratin, desmin and smooth muscle actin antibodies. Ultrastructurally, neoplastic cells were characterized by numerous mitochondria surrounded by endoplasmic reticulum and contained few secondary lysosomes. This tumour was diagnosed as a subcutaneous peripheral nerve sheath tumour (PNST) with pseudoglandular architecture. This case illustrates the morphological diversity of PNST and provides new insight into the differential diagnosis of cutaneous tumours of similar morphology in the dog.

  20. Clinical course of a malignant peripheral nerve sheath tumor in a Siberian tiger (Panthera tigris altaica).

    PubMed

    Steinmetz, Hanspeter W; Rütten, Maja; Ruess-Melzer, Katja; Ohlerth, Stefanie; Lischer, Christoph; Oevermann, Anna; Bode-Lesniewska, Beata; Hatt, Jean-Michel

    2010-11-01

    A 14-year-old male Siberian tiger (Panthera tigris altaica) was admitted with an ulcerating mass on the right thoracic wall. Radiographic and computed tomographic evaluation indicated 2 isolated cutaneous masses without any signs of metastasis. Histology of a Tru-Cut biopsy revealed an anaplastic sarcoma with giant cells. Both tumors were resected with appropriate normal tissue margins. The size of the defect did not allow primary closure of the wound; therefore, a mesh expansion technique was attempted. Three months later, the tiger had to be euthanized due to extensive metastasis to the lungs. Histomorphological features and immunohistochemical results confirmed the diagnosis of malignant peripheral nerve sheath tumor. In contrast to domestic animal experience, the tumor had spread extensively to the lungs without local reccurrence in a short period of time. Correct diagnosis requires various immunohistochemical evaluations of the tumor tissue.

  1. Malignant peripheral nerve sheath tumor presenting as orbito temporal lump: Case report and review of literature

    PubMed Central

    Panigrahi, Souvagya; Mishra, Sudhansu S.; Mishra, Sanjib; Das, Srikant

    2016-01-01

    Malignant peripheral nerve sheath tumor (MPNST) is a rare soft tissue sarcoma. The most common anatomical sites include the upper and lower extremities and trunk and less commonly the head and neck. To our knowledge, few patients with a cranial or facial MPNST have been reported. We report such a lesion in a 35-year-old woman who presented with left sided rapidly progressive proptosis and visual loss due to an orbital lump extending up to the temporal lobe. Cranial imaging showed a huge mass invading the orbital wall and temporal bone. The presumptive diagnosis was a malignant orbital tumor. Preoperative fine needle aspiration cytology of the orbital mass came to be neurofibroma. Near total resection of the tumor was done. Histopathology revealed MPNST which was subsequently confirmed on the basis of immunopositivity for S-100. The patient recovered uneventfully and was discharged 8 days after surgery with an advice to attend cancer institute for possible radiotherapy. PMID:27057226

  2. Multicentric benign peripheral nerve sheath tumors in two related bearded dragons, Pogona vitticeps.

    PubMed

    Lemberger, K Y; Manharth, A; Pessier, A P

    2005-07-01

    Multiple subcutaneous masses from two sibling bearded dragons were removed. Nodules were well demarcated, restricted to the subcutis, and soft, white to yellow, resembling adipose tissue. Histologically, the masses were composed of short interlacing streams and bundles of spindle cells, with regions of vague nuclear palisading. Two of the tumors contained a subpopulation of polygonal cells with abundant periodic acid-Schiff (PAS)-positive cytoplasmic granules. Neoplastic cells were immunohistochemically positive for S100 and neuron-specific enolase (NSE) but negative for desmin and smooth muscle actin. Electron microscopy and reticulin stains demonstrated a continuous basal lamina separating intertwining cells. Histologic, ultrastructural, and immunohistochemical features were consistent with a peripheral nerve sheath origin. At 1 year postexcision, local reoccurrence of a single incompletely excised mass from the left shoulder was noted.

  3. Epineural Sheath Jacket as a New Surgical Technique for Neuroma Prevention in the Rat Sciatic Nerve Model.

    PubMed

    Siemionow, Maria; Bobkiewicz, Adam; Cwykiel, Joanna; Uygur, Safak; Francuzik, Wojciech

    2017-10-01

    Terminal neuromas resulting from severe nerve injuries and traumatic or surgical limb amputations can become a source of pain, and significantly impair patients' quality of life. Recently, the number of patients with peripheral nerve injuries increased due to modern war conflicts, natural disasters, and traffic accidents. This study investigated the efficacy of the epineural sheath jacket (ESJ) as a novel technique for neuroma prevention in the rat sciatic nerve model. A 20-mm segment of the right sciatic nerve was excised in 18 Lewis rats, and the animals were divided into 3 experimental groups (n = 6/group): group I-control, nerve stump without protection; group II-muscle burying group, nerve stump buried in the muscle; group III-ESJ group, nerve stump protected by ESJ. The ESJ was created from the excised sciatic nerve and applied as a "cap" over the proximal nerve stump. The presence of neuropathic pain was assessed weekly by pinprick test and Tinel sign, up to 24 weeks postsurgery. At 24 weeks, assessments, such as macroscopic evaluation, retrograde neuronal labeling analysis, histomorphometry, and neural/connective tissue ratio were performed. Epineural sheath jacket significantly reduced neuroma formation, which was associated with decreased Tinel sign (16.7%, P < 0.05) response compared with the nerve stump control. Moreover, ESJ reduced axonal sprouting, bulb-shaped nerve ending formation and perineural adhesions, as confirmed by macroscopic evaluation. Histological evaluation confirmed that nerve stumps protected with the ESJ showed less fibrosis and presented well-organized axonal structure. Neural/connective tissue ratio and retrograde neuronal labeling analysis revealed significantly improved results in the ESJ group compared to the control nerve stump group (P = 0.032 and P = 0.042, respectively). The protective effect of the ESJ against neuroma formation was confirmed by behavioral and histological analyses, showing outcomes comparable to the muscle

  4. Tamoxifen inhibits malignant peripheral nerve sheath tumor growth in an estrogen receptor–independent manner

    PubMed Central

    Byer, Stephanie J.; Eckert, Jenell M.; Brossier, Nicole M.; Clodfelder-Miller, Buffie J.; Turk, Amy N.; Carroll, Andrew J.; Kappes, John C.; Zinn, Kurt R.; Prasain, Jeevan K.; Carroll, Steven L.

    2011-01-01

    Few therapeutic options are available for malignant peripheral nerve sheath tumors (MPNSTs), the most common malignancy associated with neurofibromatosis type 1 (NF1). Guided by clinical observations suggesting that some NF1-associated nerve sheath tumors are hormonally responsive, we hypothesized that the selective estrogen receptor (ER) modulator tamoxifen would inhibit MPNST tumorigenesis in vitro and in vivo. To test this hypothesis, we examined tamoxifen effects on MPNST cell proliferation and survival, MPNST xenograft growth, and the mechanism by which tamoxifen impeded these processes. We found that 1–5 μM 4-hydroxy-tamoxifen induced MPNST cell death, whereas 0.01–0.1 μM 4-hydroxy-tamoxifen inhibited mitogenesis. Dermal and plexiform neurofibromas, MPNSTs, and MPNST cell lines expressed ERβ and G-protein-coupled ER-1 (GPER); MPNSTs also expressed estrogen biosynthetic enzymes. However, MPNST cells did not secrete 17β-estradiol, exogenous 17β-estradiol did not stimulate mitogenesis or rescue 4-hydroxy-tamoxifen effects on MPNST cells, and the steroidal antiestrogen ICI-182,780 did not mimic tamoxifen effects on MPNST cells. Further, ablation of ERβ and GPER had no effect on MPNST proliferation, survival, or tamoxifen sensitivity, indicating that tamoxifen acts via an ER-independent mechanism. Consistent with this hypothesis, inhibitors of calmodulin (trifluoperazine, W-7), another known tamoxifen target, recapitulated 4-hydroxy-tamoxifen effects on MPNST cells. Tamoxifen was also effective in vivo, demonstrating potent antitumor activity in mice orthotopically xenografted with human MPNST cells. We conclude that 4-hydroxy-tamoxifen inhibits MPNST cell proliferation and survival via an ER-independent mechanism. The in vivo effectiveness of tamoxifen provides a rationale for clinical trials in cases of MPNSTs. PMID:21075781

  5. Initial clinical experience with image-guided linear accelerator-based spinal radiosurgery for treatment of benign nerve sheath tumors.

    PubMed

    Selch, Michael T; Lin, Kevin; Agazaryan, Nzhde; Tenn, Steve; Gorgulho, Alessandra; DeMarco, John J; DeSalles, Antonio A F

    2009-12-01

    Stereotactic radiosurgery has proven a safe and effective treatment of cranial nerve sheath tumors. A similar approach should be successful for histologically identical spinal nerve sheath tumors. The preliminary results of linear accelerator-based spinal radiosurgery were retrospectively reviewed for a group of 25 nerve sheath tumors. Tumor location was cervical 11, lumbar 10, and thoracic 4. Thirteen tumors caused sensory disturbance, 12 pain, and 9 weakness. Tumor size varied from 0.9 to 4.1 cm (median, 2.1 cm). Radiosurgery was performed with a 60-MV linear accelerator equipped with a micro-multileaf collimator. Median peripheral dose and prescription isodose were 12 Gy and 90%, respectively. Image guidance involved optical tracking of infrared reflectors, fusion of amorphous silicon radiographs with dynamically reconstructed digital radiographs, and automatic patient positioning. Follow-up varied from 12 to 58 months (median, 18). There have been no local failures. Tumor size remained stable in 18 cases, and 7 (28%) demonstrated more than 2 mm reduction in tumor size. Of 34 neurologic symptoms, 4 improved. There has been no clinical or imaging evidence for spinal cord injury. One patient had transient increase in pain and one transient increase in numbness. Results of this limited experience indicate linear accelerator-based spinal radiosurgery is feasible for treatment of benign nerve sheath tumors. Further follow-up is necessary, but our results imply spinal radiosurgery may represent a therapeutic alternative to surgery for nerve sheath tumors. Symptom resolution may require a prescribed dose of more than 12 Gy. Copyright 2009 Elsevier Inc. All rights reserved.

  6. Direct Surgery of Previously Coiled Large Internal Carotid Ophthalmic Aneurysm for the Purpose of Optic Nerve Decompression.

    PubMed

    Kawabata, Shuhei; Toyota, Shingo; Kumagai, Tetsuya; Goto, Tetsu; Mori, Kanji; Taki, Takuyu

    2017-01-01

    Background Progressive visual loss after coil embolization of a large internal carotid ophthalmic aneurysm has been widely reported. It is generally accepted that the primary strategy for this complication should be conservative, including steroid therapy; however, it is not well known as to what approach to take when the conservative therapy is not effective. Case Presentation We report a case of a 55-year-old female presenting with progressive visual loss after the coiling of a ruptured large internal carotid ophthalmic aneurysm. As the conservative therapy had not been effective, we performed neck clipping of the aneurysm with optic canal unroofing, anterior clinoidectomy, and partial removal of the embolized coils for the purpose of optic nerve decompression. After the surgery, the visual symptom was improved markedly. Conclusions It is suggested that direct surgery for the purpose of optic nerve decompression may be one of the options when conservative therapy is not effective for progressive visual disturbance after coil embolization.

  7. Relationship between peripheral nerve decompression and gain of pedal sensibility and balance in patients with peripheral neuropathy.

    PubMed

    Ducic, Ivica; Taylor, Nathan S; Dellon, A Lee

    2006-02-01

    This was an initial exploratory study to determine if decompression of the 4 medial ankle tunnels (neurolysis of the tibial, medial and lateral plantar, and calcaneal nerves) could lead to improved foot sensibility, increased proprioception and balance, and decreased falls in a population of patients with impaired lower extremity sensation. Fourteen patients with peripheral neuropathy were included in this study. Seventy-one percent of patients were females. Average age was 67 years. All patients were evaluated preoperatively and postoperatively to assess their lower extremity sensibility, as well as their ability to stand still, maintaining their balance with their eyes open and then closed, which is defined as "sway." Lower extremity sensibility was measured with the Pressure-Specified Sensory Device (PSSD), which evaluates 1- and 2-point discrimination for the pulp of the big toe and medial heel. The MatScan Measurement System measured each patient's sway. Neuropathy was the result of diabetes in 72% of patients, a combination of diabetes and hypothyroidism in 7%, chemotherapy in 7%, and idiopathic in 14%. Eight patients underwent peripheral nerve decompression on 1 lower extremity, whereas 6 patients underwent bilateral lower extremity peripheral nerve decompression. Mean toe and heel sensibility improved 9% and 7%, respectively, in the unilateral group, whereas the bilateral group experienced an improvement in mean toe and heel sensibility of 42% (P = 0.02) and 32%, respectively. Preoperative and postoperative sway comparison in the unilateral group revealed a reduction in sway with eyes open and eyes closed by 5% and 31%, respectively. Comparison of preoperative and postoperative sway in the bilateral group showed a reduction with eyes open and eyes closed by 23% and 145% (P = 0.05), respectively. This initial study suggests that there may be benefit from bilateral lower extremity peripheral nerve decompression in helping improve pedal sensibility and balance

  8. Decompression of the inferior alveolar nerve to treat the pain of the mandible caused by fibrous dysplasia-case report

    PubMed Central

    Wei, Wen-Bin; Chen, Min-Jie; Yang, Chi; Zhang, Wenhao; Wang, Yiwen

    2015-01-01

    Fibrous dysplasia is a kind of benign bone lesion characterized by the manifestation of the replacement of the normal substance of bone by fibro-osseous connective tissue. A patient diagnosed fibrous dysplasia had unbearable pain in the left mandibular region only. To treat the patient, an navigation template was designed to guide the decompression of inferior alveolar nerve, and piezosurgery was performed to do the osteotomy. After the surgery, the pain disappeared. The sensation of the lower lip recovered. PMID:26770606

  9. [Teflon granuloma after microvascular decompression of the trigeminal nerve root in a patient with recurrent trigeminal neuralgia].

    PubMed

    Rzaev, D A; Kulikova, E V; Moysak, G I; Voronina, E I; Ageeva, T A

    2016-01-01

    The use of a Teflon implant for Jannetta surgery in patients with trigeminal neuralgia is complicated in rare cases by the development of a Teflon granuloma and can cause recurrent facial pain. The article presents a clinical case of a Teflon granuloma developed after microvascular decompression of the trigeminal nerve root, describes the surgical findings and histological picture, and analyzes the literature, causes of granuloma development, and recommendations for treatment of these patients.

  10. Effects of acute controlled changes in end-tidal carbon dioxide on the diameter of the optic nerve sheath: a transorbital ultrasonographic study in healthy volunteers.

    PubMed

    Dinsmore, M; Han, J S; Fisher, J A; Chan, V W S; Venkatraghavan, L

    2017-02-08

    Transorbital ultrasonographic measurement of the diameter of the optic nerve sheath is a non-invasive, bed-side examination for detecting raised intracranial pressure. However, the ability of the optic nerve sheath diameter to predict acute changes in intracranial pressures remains unknown. The aim of this study was to examine the dynamic changes of the optic nerve sheath diameter in response to mild fluctuations in cerebral blood volume induced by changes in end-tidal carbon dioxide. We studied 11 healthy volunteers. End-tidal carbon dioxide was controlled by a model-based prospective end-tidal targeting system (RespirAct™). The volunteers' end-tidal carbon dioxide was targeted and maintained for 10 min each at normocapnia (baseline); hypercapnia (6.5 kPa); normocapnia (baseline 1); hypocapnia (3.9 kPa) and on return to normocapnia (baseline 2). A single investigator repeatedly measured the optic nerve sheath diameter for 10 min at each level of carbon dioxide. With hypercapnia, there was a significant increase in optic nerve sheath diameter, with a mean (SD) increase from baseline 4.2 (0.7) mm to 4.8 (0.8) mm; p < 0.001. On return to normocapnia, the optic nerve sheath diameter rapidly reverted back to baseline values. This study confirms dynamic changes in the optic nerve sheath diameter with corresponding changes in carbon dioxide, and their reversibly with normocapnia.

  11. Effects of decompression on behavioral, electrophysiologic, and histomorphologic recovery in a chronic sciatic nerve compression model of streptozotocin-induced diabetic rats

    PubMed Central

    Wang, Ping-Hui; Yang, Cheng-Chang; Su, Wei-Ren; Wu, Po-Ting; Cheng, Shun-Chien; Jou, I-Ming

    2017-01-01

    Purpose To determine susceptibility to decompression surgery in diabetic and nondiabetic peripheral neuropathy using a chronic compression neuropathy model. Materials and methods Twenty-four streptozotocin-induced diabetic rats were randomly divided into three groups: group I, chronic compression of the left sciatic nerve for 4 weeks with decompression; group II, similar without decompression; and group III, sham exposing the sciatic nerve only. The other 24 nondiabetic rats were assigned to groups IV–VI, which received compression–decompression, compression, and the sham operation, respectively. Mixed-nerve-elicited somatosensory evoked potentials (M-SSEPs) and compound muscle action potentials (CMAPs) were measured to verify the compression neuropathy in the posttreatment follow-up. Behavioral observations in thermal hyperalgesia tests were quantified before electrophysiologic examinations. Treated and contralateral nerves were harvested for histomorphologic analysis. Results Chronic compression of sciatic nerve induced significant reduction of amplitude and increment of latency of M-SSEP and CMAP in both diabetic and nondiabetic rats. Diabetic group changes were more susceptible. Decompression surgery significantly improved both sensory and motor conduction, thermal hyperalgesia, and the mean myelin diameter of the rat sciatic nerve in both diabetic and nondiabetic groups. Near full recovery of motor and sensory function occurred in the nondiabetic rats, but not in the diabetic rats 8 weeks postdecompression. Conclusion Behavioral, electrophysiologic, and histomorphologic findings indicate that decompression surgery is effective in both diabetic and nondiabetic peripheral neuropathy. PMID:28360533

  12. Decompression endoscopic surgery for frontal secondary headache attributed to supraorbital and supratrochlear nerve entrapment: a comprehensive review.

    PubMed

    Filipović, Boris; de Ru, J Alexander; van de Langenberg, Rick; Borggreven, Pepijn A; Lacković, Zdravko; Lohuis, Peter J F M

    2017-05-01

    In the last decade, a new surgical treatment modality was developed for frontal secondary headache, based on the assumption that the trigger of this pain entity is the entrapment of peripheral sensory nerves. The surgery entails a procedure, where an endoscopic approach is used to decompress the supraorbital and supratrochlear nerve branches, which are entrapped by the periosteum in the region of the corrugator supercilii muscle. Candidates for the surgery define their headache as moderate to severe persistent daily pressure or tension, localized in the frontal area, sometimes accompanied by symptoms of nausea and photophobia mimicking a primary headache-migraine. We created a step-by-step screening algorithm which is used to differentiate patients that have the highest chance for a successful surgical decompression. Up to now, published data regarding this type of surgery demonstrate long-lasting successful outcomes while adverse effects are minor. This article reviews and discusses from a surgeon's perspective decompression surgery for secondary headache attributed to supraorbital and supratrochlear nerve entrapment.

  13. Quantification of the learning curve for arthroscopic suprascapular nerve decompression: an evaluation of 300 cases.

    PubMed

    Yamakado, Kotaro

    2015-02-01

    This study aimed to quantify the learning curve for arthroscopic suprascapular nerve decompression (SSND) using the log-linear model. Three hundred consecutive patients underwent arthroscopic SSND by release of the transverse scapular ligament at the suprascapular notch by a single surgeon. Cases with a bony suprascapular nerve foramen were excluded. The arthroscopic SSND time was defined as the time from the beginning of shaving the soft tissue medial to the acromioclavicular joint until the completion of the transverse scapular ligament release. Regression analysis was applied to predict the time required for SSND on the basis of the cumulative case volume after logarithmic transformation of both statistics. The mean SSND time decreased from the first 50 cases (mean, 29.5 minutes) to the last 50 cases (mean, 6.2 minutes). The estimated SSND times of the first and last 50 cases were 25.1 minutes and 5.5 minutes, respectively. A significant linear correlation was observed between the SSND time and the cumulative volume of cases after logarithmic transformation (r(2) = 0.481, P < .01), and the best-fit linear equation was calculated as log y = -0.52 log x + 4.6, where y represents the estimated SSND time and x represents the cumulative volume of cases, resulting in an estimated learning rate of 69.7% (which equals 2(-0.52)). This study presents the overall time reduction in arthroscopic SSND in support of a learning-curve effect. Furthermore, this study quantifies the learning rate, estimated as approximately 70%, indicating that the time required for arthroscopic SSND can decrease by up to 30% when the cumulative volume of cases doubles. Level II, prospective comparative study. Copyright © 2015 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  14. Malignant peripheral nerve sheath tumour (MPNST): the clinical implications of cellular signalling pathways.

    PubMed

    Katz, Daniela; Lazar, Alexander; Lev, Dina

    2009-10-19

    Malignant peripheral nerve sheath tumour (MPNST) is a rare malignancy accounting for 3-10% of all soft tissue sarcomas. Most MPNSTs arise in association with peripheral nerves or deep neurofibromas and may originate from neural crest cells, although the specific cell of origin is uncertain. Approximately half of MPNSTs occur in the setting of neurofibromatosis type 1 (NF1), an autosomal dominant disorder with an incidence of approximately one in 3500 persons; the remainder of MPNSTs develop sporadically. In addition to a variety of clinical manifestations, approximately 8-13% of NF1 patients develop MPNSTs, which are the leading cause of NF1-related mortality. Surgical resection is the mainstay of MPNST clinical management. However, because of invasive growth, propensity to metastasise, and limited sensitivity to chemotherapy and radiation, MPNST has a guarded to poor prognosis. Five-year survival rates of only 20-50% indicate an urgent need for improved therapeutic approaches. Recent work in this field has identified several altered intracellular signal transduction cascades and deregulated tyrosine kinase receptors, posing the possibility of personalised, targeted therapeutics. However, expanded knowledge of MPNST molecular pathobiology will be needed to meaningfully apply such approaches for the benefit of afflicted patients.

  15. Medullary metastasis of a malignant peripheral nerve sheath tumor: A case report

    PubMed Central

    Hagi, Tomohito; Nakamura, Tomoki; Yokoji, Ayumu; Matsumine, Akihiko; Sudo, Akihiro

    2016-01-01

    The present study reports a case of medullary metastasis without lung metastasis that occurred as a result of a malignant peripheral nerve sheath tumor (MPNST). An 81-year-old woman presented with a MPNST in the left brachial plexus, arising from the cervical nerve root. The patient underwent carbon ion radiotherapy; however, tumor recurrence was identified in the left shoulder. Subsequently, the patient underwent wide excision. Three weeks subsequent to surgery, imbalance and dysarthria developed suddenly. Dysphagia emerged and left upper limb pain disappeared on the day after symptom development. Magnetic resonance imaging (MRI) revealed that this was due to metastasis to the medulla. Five days subsequent to the onset of dysarthria, the patient succumbed due to respiratory failure. To the best of our knowledge, no previous cases of medullary metastasis arising from a MPNST in the absence of lung metastasis have been reported. MRI is a useful examination tool for the identification of brain metastases; however, the high cost of MRI as a routine examination must be considered due to the rarity of brain metastases. Therefore, methods to detect brain metastasis warrant further investigation. PMID:27588138

  16. Superficial or cutaneous malignant peripheral nerve sheath tumor--clinical experience at Taipei Veterans General Hospital.

    PubMed

    Feng, Chin-Jung; Ma, Hsu; Liao, Wen-Chieh

    2015-05-01

    Primary malignant peripheral nerve sheath tumors (MPNSTs) with a cutaneous or subcutaneous origin represent a small subset of MPNSTs thought to be derived from cutaneous neurofibromas or small peripheral nerves. Few cases of superficial MPNSTs originating from the skin have been reported in the literature. From October 1999 to February 2014, 13 patients were diagnosed with superficial or cutaneous MPNSTs and received treatment at Taipei Veterans General Hospital. Clinical data were collected via retrospective chart review. A retrospective study was performed to compare superficial and deep-seated lesions in terms of local recurrence, distal metastasis, and survival analysis. The relevant literature is also briefly reviewed. The most frequent initial symptoms were local swelling and pain. Ten tumors were found in the extremities, and 3 tumors were located on the trunk. All patients underwent surgery with curative intent. Four patients developed local recurrence, and 3 developed distant metastasis. Three of 13 patients died after a follow-up period of 11 to 180 months (mean, 53.4). Compared to deep-seated MPNSTs, superficial MPNSTs had a lower histopathological grading and better survival rate. Superficial MPNSTs are a rare variant of MPNST. The relatively frequent lack of associated neurofibromatosis and superficial location within the dermis and subcutis may result in this entity being overlooked. According to our clinical experience, superficial MPNSTs might have better prognosis, but similar recurrence and metastasis rates compared with deep-seated lesions. Hence, awareness of this entity should prompt its consideration in the differential diagnosis of cutaneous sarcomas.

  17. Optic nerve sheath distention in Leber's optic neuropathy and the significance of the "Wallace mutation".

    PubMed

    Smith, J L; Tse, D T; Byrne, S F; Johns, D R; Stone, E M

    1990-12-01

    We recently encountered a 27-year-old man who presented an atypical clinical picture of Leber's hereditary optic neuropathy: His family history was negative, visual loss continued steadily for over 8 months, circumpapillary microangiopathy was equivocal, the optic discs showed large physiologic cups, and both optic nerve sheaths were notably distended with increased subarachnoid fluid. The latter was confirmed by ultrasonography, computed tomography, and magnetic resonance imaging. The patient's asymptomatic brother also showed unimpressive circumpapillary microangiopathy in the fundi. The asymptomatic mother from France was then seen, and she showed classic circumpapillary microangiopathy in the fundi. Studies of mitochondrial DNA showed the classic point mutation at position 11778 as reported by Wallace in all three family members. Another patient previously seen with classic Leber's hereditary optic neuropathy recently had mitochondrial DNA studies along with three other affected family members and five unaffected family members in the maternal lineage. All nine of these individuals were completely normal at the Wallace locus. In fact, sequencing of the entire ND-4 gene from one affected individual revealed it to be perfectly normal at the amino acid level. The importance of obtaining quantitative ultrasonography and the 30 degrees test, and studying mitochondrial DNA in patients suspected of having Leber's optic nerve disease is emphasized.

  18. Degree of distal trigeminal nerve atrophy predicts outcome after microvascular decompression for Type 1a trigeminal neuralgia.

    PubMed

    Duan, Yifei; Sweet, Jennifer; Munyon, Charles; Miller, Jonathan

    2015-12-01

    Trigeminal neuralgia is often associated with nerve atrophy, in addition to vascular compression. The authors evaluated whether cross-sectional areas of different portions of the trigeminal nerve on preoperative imaging could be used to predict outcome after microvascular decompression (MVD). A total of 26 consecutive patients with unilateral Type 1a trigeminal neuralgia underwent high-resolution fast-field echo MRI of the cerebellopontine angle followed by MVD. Preoperative images were reconstructed and reviewed by 2 examiners blinded to the side of symptoms and clinical outcome. For each nerve, a computerized automatic segmentation algorithm was used to calculate the coronal cross-sectional area at the proximal nerve near the root entry zone and the distal nerve at the exit from the porus trigeminus. Findings were correlated with outcome at 12 months. After MVD, 17 patients were pain free and not taking medications compared with 9 with residual pain. Across all cases, the coronal cross-sectional area of the symptomatic trigeminal nerve was significantly smaller than the asymptomatic side in the proximal part of the nerve, which was correlated with degree of compression at surgery. Atrophy of the distal trigeminal nerve was more pronounced in patients who had residual pain than in those with excellent outcome. Among the 7 patients who had greater than 20% loss of nerve volume in the distal nerve, only 2 were pain free and not taking medications at long-term follow-up. Trigeminal neuralgia is associated with atrophy of the root entry zone of the affected nerve compared with the asymptomatic side, but volume loss in different segments of the nerve has very different prognostic implications. Proximal atrophy is associated with vascular compression and correlates with improved outcome following MVD. However, distal atrophy is associated with a significantly worse outcome after MVD.

  19. A distal ileum malignant peripheral nerve sheath tumor causing intussusception in a patient in China: a case report.

    PubMed

    Zhu, Lin-Bo; Li, Peng-Fei; Xiao, Wei-Hua; Zhang, Peng-Bin; Li, Jun-Qiang; Sun, Ming-Fei

    2017-01-19

    Malignant peripheral nerve sheath tumors (MPNSTs) arise from a peripheral nerve or display nerve sheath differentiation. Most MPNSTs typically originate on the trunk, extremities, head, neck, and paravertebral regions. Gastrointestinal MPNSTs are rare entities with only 10 cases reported worldwide in the literatures. Here, we report the first Chinese case of a malignant peripheral nerve sheath tumor of the distal ileum presenting as intussusception. A 53-year-old female patient without pathological antecedent for neurofibromatosis was admitted with pain in the right lower abdomen and multiple episodes of vomiting for 1 week. Preoperative diagnosis was intussusception with a contrast-enhanced computed tomography scan (CECT) of the abdomen showing characteristic target sign. Due to difficulty reducing the ileum-colon intussusception, right hemicolectomy with ileocolostomy was performed. Histopathology was suggestive of low-grade MPNST. The patient received postoperative care and was followed up for 9 months. There is no sign of tumor recurrence and metastatic disease. This case is unique in terms of a rare tumor presenting with unusual complication.

  20. Neurovascular decompression of the rostral ventrolateral medulla decreases blood pressure and sympathetic nerve activity in patients with refractory hypertension.

    PubMed

    Sasaki, Susumu; Tanda, Shuji; Hatta, Tsuguru; Morimoto, Satoshi; Takeda, Kazuo; Kizu, Osamu; Tamaki, Shinji; Saito, Mitsuru; Tamura, Yoji; Kondo, Akinori

    2011-11-01

    Recently, the authors experienced four patients who had refractory hypertension and neurovascular compression of the rostral ventrolateral medulla (RVLM). One of them, a 49-year-old woman, had undergone continuous intravenous drip injections of calcium channel blockers and β-blockers for more than 3 years because of severe and refractory hypertension. The patients had undergone microvascular decompression (MVD) of the RVLM, and the changes in blood pressure (BP) and sympathetic nerve activities were recorded. In these patients, BP decreased to the normal range without any antihypertensive drugs 2 to 3 months after MVD. The tibial sympathetic nerve activities under resting and stress conditions significantly decreased, and plasma levels of norepinephrine, urinary levels of adrenaline, and plasma renin activity were also significantly decreased after MVD of RVLM. In some patients with refractory hypertension, arterial compression of the RVLM enhances sympathetic nerve activity and renin-angiotensin system to thereby increase BP. In these patients, the operative decompression of the RVLM could lower BP via restoration of sympathetic nerve activities and the renin-angiotensin system.

  1. Angiofollicular lymph node hyperplasia resembling a spinal nerve sheath tumor: a rare case of Castleman's disease.

    PubMed

    Stevens, E Andrew; Strowd, Roy E; Mott, Ryan T; Oaks, Timothy E; Wilson, John A

    2009-09-01

    Angiofollicular lymph node hyperplasia (Castleman's disease) is a lymphoproliferative disorder of unknown etiology. Although uncommon, the localized form of this disease can manifest in the central nervous system, typically as a meningeal-based intracranial lesion. Castleman's disease involving the spine is exceedingly rare. This represents only the second reported case of a patient with Castleman's disease whose presentation mimicked that of a spinal nerve sheath tumor. We report a rare case of angiofollicular lymph node hyperplasia that mimicked a spinal nerve sheath tumor and was treated with gross total resection. Case report. A 31-year-old female with angiofollicular lymph node hyperplasia presenting with a paraspinal mass. The patient's outcome was based on clinical history, physical and radiographic examinations. A 31-year-old woman with a mediastinal mass previously diagnosed as sarcoid via biopsy presented with the new onset of radicular pain and radiographic enlargement of her mass. Magnetic resonance imaging demonstrated a 4.3x5.7x6.0 cm homogenously enhancing soft-tissue lesion that emanated from and widened the T3/T4 neural foramen on the left. The differential diagnosis based on the location of the lesion and imaging characteristics included schwannoma, neurofibroma, paraganglioma, sarcoid, and lymphoma. Gross total resection was performed via thoracotomy. Histological examination identified angiofollicular lymph node hyperplasia (Castleman's disease) of the hyaline-vascular subtype. The patient did not receive adjuvant chemotherapy or radiation therapy. The patient had resolution of her symptoms without any clinical or radiographic evidence of recurrence at 1-year follow-up using magnetic resonance imaging with and without contrast. Castleman's disease is a rare pathologic entity that should be considered in the differential diagnosis of a patient with a paraspinal mass. Spine surgeons should be aware of this diagnosis as it has treatment and follow

  2. Malignant peripheral nerve sheath tumor of adrenal gland with heterologus osseous differentiation in a case of Von Recklinghausen's disease.

    PubMed

    Baisakh, Manas R; Mohapatra, Nachiketa; Adhikary, Samiran D; Routray, Debasis

    2014-01-01

    Malignant peripheral nerve sheath tumor (MPNST) of the adrenal gland is extremely rare. Most of them occur in association with neurofibromatosis, ganglioneuroma or as part of a composite tumor such as pheochromocytoma. Only seven cases of MPNST of the adrenal gland have been reported in the literature till date. Discriminating this entity from other soft tissue sarcomas and gastrointestinal stromal tumor of the adrenal gland has important diagnostic and therapeutic implications. Moreover, the tumor size and pattern of expression for certain immunohistochemical markers may serve as independent predictors of aggressiveness. Herein we present a 24-years-old male with features of Von Recklinghausen's disease who presented with large left adrenal gland malignant peripheral nerve sheath tumor.

  3. Schwannoma of the tibial nerve sheath as a cause of tarsal tunnel syndrome--a case study.

    PubMed

    Milnes, Helen L; Pavier, Julian C

    2012-09-01

    A schwannoma is a benign, encapsulated and non-invasive tumour whose origin is derived from Schwann cells. Its incidence in the foot and ankle is rare. The etiology, incidence, clinical presentation, histology, differential diagnoses and surgical treatment are discussed. The authors present a case of a schwannoma of the tibial nerve sheath causing tarsal tunnel syndrome of the foot. The diagnosis in this case was delayed for eight years, which unfortunately is not uncommon with pedal schwannomas.

  4. Visual Outcome and Tumor Control After Conformal Radiotherapy for Patients With Optic Nerve Sheath Meningioma

    SciTech Connect

    Arvold, Nils D.; Lessell, Simmons; Bussiere, Marc; Beaudette, Kevin; Rizzo, Joseph F.; Loeffler, Jay S.; Shih, Helen A.

    2009-11-15

    Purpose: Optic nerve sheath meningioma (ONSM) is a rare tumor that almost uniformly leads to visual dysfunction and even blindness without intervention. Because surgical extirpation carries a high risk of postoperative blindness, vision-sparing treatment strategies are desirable. Methods and Materials: We retrospectively reviewed the outcomes of 25 patients (25 optic nerves) with ONSM, treated at a single institution with conformal fractionated radiotherapy by either stereotactic photon or proton radiation. Primary endpoints were local control and visual acuity. Results: The patients presented with symptoms of visual loss (21) or orbital pain (3) or were incidentally diagnosed by imaging (3). The mean age was 44 years, and 64% were female patients. The indication for treatment was the development or progression of symptoms. Of the patients, 13 were treated with photons, 9 were treated with protons, and 3 received a combination of photons and protons. The median dose delivered was 50.4 gray equivalents (range, 45-59.4 gray equivalents). Median follow-up after radiotherapy was 30 months (range, 3-168 months), with 3 patients lost to follow-up. At most recent follow-up, 21 of 22 patients (95%) had improved (14) or stable (7) visual acuity. One patient had worsened visual acuity after initial postirradiation improvement. Of the 22 patients, 20 (95%) had no radiographic progression. Three patients had evidence of asymptomatic, limited retinopathy on ophthalmologic examination, and one had recurrent ONSM 11 years after treatment. Conclusions: Highly conformal, fractionated radiation therapy for symptomatic primary ONSM provides tumor control and improvement in visual function in most cases, with minimal treatment-induced morbidity. Longer follow-up is needed to assess the durability of tumor control and treatment-related late effects.

  5. Trp53 Haploinsufficiency Modifies EGFR-Driven Peripheral Nerve Sheath Tumorigenesis

    PubMed Central

    Rahrmann, Eric P.; Moriarity, Branden S.; Otto, George M.; Watson, Adrienne L.; Choi, Kwangmin; Collins, Margaret H.; Wallace, Margaret; Webber, Beau R.; Forster, Colleen L.; Rizzardi, Anthony E.; Schmechel, Stephen C.; Ratner, Nancy; Largaespada, David A.

    2015-01-01

    Malignant peripheral nerve sheath tumors (MPNSTs) are genetically diverse, aggressive sarcomas that occur sporadically or in association with neurofibromatosis type 1 syndrome. Reduced TP53 gene expression and amplification/overexpression of the epidermal growth factor receptor (EGFR) gene occur in MPNST formation. We focused on determining the cooperativity between reduced TP53 expression and EGFR overexpression for Schwann cell transformation in vitro (immortalized human Schwann cells) and MPNST formation in vivo (transgenic mice). Human gene copy number alteration data, microarray expression data, and TMA analysis indicate that TP53 haploinsufficiency and increased EGFR expression co-occur in human MPNST samples. Concurrent modulation of EGFR and TP53 expression in HSC1λ cells significantly increased proliferation and anchorage-independent growth in vitro. Transgenic mice heterozygous for a Trp53-null allele and overexpressing EGFR in Schwann cells had a significant increase in neurofibroma and grade 3 PNST (MPNST) formation compared with single transgenic controls. Histological analysis of tumors identified a significant increase in pAkt expression in grade 3 PNSTs compared with neurofibromas. Array comparative genome hybridization analysis of grade 3 PNSTs identified recurrent focal regions of chromosomal gains with significant enrichment in genes involved in extracellular signal–regulated kinase 5 signaling. Collectively, altered p53 expression cooperates with overexpression of EGFR in Schwann cells to enhance in vitro oncogenic properties and tumorigenesis and progression in vivo. PMID:24832557

  6. Malignant peripheral nerve sheath tumor as a cause of chronic cardiac insufficiency in cattle

    PubMed Central

    2013-01-01

    Chronic cardiac insufficiency was associated with a malignant peripheral nerve sheath tumor in a cow. An eight-year-old cow developed a progressive condition (over a period of three months) characterized by an enhanced abdominal volume, reluctance to move, a positive jugular pulse, watery diarrhea and death. At necropsy, moderate subcutaneous edema and an enhanced hepatic lobular pattern were observed. A 23x20x11 cm firm, grayish-white mass adhered to and infiltrated the right atrium. Multiple firm, yellowish-white nodules of 0.5 to 12 cm in diameter were diffusely scattered in the epicardium and parietal pericardium. Histologically, the tumor was poorly circumscribed with foci of infiltration of the myocardium. The neoplastic cells had two major histologic patterns, Antoni types A and B. Within occasional foci, pleomorphic cells with an epithelioid appearance were present in addition to multinucleated cells with periodic acid Schiff (PAS)-positive cytoplasmic globules. Foci of cartilaginous and granular differentiations were interspersed among the neoplastic cells. Multiple vessels presented wall hyalinization and tumoral embolus. Large necrotic foci with mineralization and cholesterol clefts were also observed. Immunohistochemically, the tumor was positive for S100 protein, vimentin and neuron-specific enolase labeling. PMID:23369465

  7. Fatty acid synthase is a metabolic oncogene targetable in malignant peripheral nerve sheath tumors

    PubMed Central

    Patel, Ami V.; Johansson, Gunnar; Colbert, Melissa C.; Dasgupta, Biplab; Ratner, Nancy

    2015-01-01

    Background Malignant peripheral nerve sheath tumors (MPNSTs) are soft tissue sarcomas with minimal therapeutic opportunities. We observed that lipid droplets (LDs) accumulate in human MPNST cell lines and in primary human tumor samples. The goal of this study was to investigate the relevance of lipid metabolism to MPNST survival and as a possible therapeutic target. Methods Based on preliminary findings that MPNSTs accumulate LDs, we hypothesized that a deregulated lipid metabolism supports MPNST cell survival/proliferation rate. To test this, we examined respiration, role of fatty acid oxidation (FAO), and the enzyme fatty acid synthase involved in de novo fatty acid synthesis in MPNSTs using both genetic and pharmacological tools. Results We demonstrate that LDs accumulate in MPNST cell lines, primary human and mouse MPNST tumors, and neural crest cells. LDs from MPNST cells disappear on lipid deprivation, indicating that LDs can be oxidized as a source of energy. Inhibition of FAO decreased oxygen consumption and reduced MPNST survival, indicating that MPNST cells likely metabolize LDs through active FAO. FAO inhibition reduced oxygen consumption and survival even in the absence of exogenous lipids, indicating that lipids synthesized de novo can also be oxidized. Consequently, inhibition of de novo fatty acid synthesis, which is overexpressed in human MPNST cell lines, effectively reduced MPNST survival and delayed induction of tumor growth in vivo. Conclusion Our results show that MPNSTs depend on lipid metabolic pathways and suggest that disrupting lipid metabolism could be a potential new strategy for the development of MPNST therapeutics. PMID:26116612

  8. Malignant peripheral nerve sheath tumor with and without neurofibromatosis type 1.

    PubMed

    Vasconcelos, Roberto André Torres de; Coscarelli, Pedro Guimarães; Alvarenga, Regina Papais; Acioly, Marcus André

    2017-06-01

    In this study, we review the institution's experience in treating malignant peripheral nerve sheath tumors (MPNSTs). A secondary aim was to compare outcomes between MPNSTs with and without neurofibromatosis type 1 (NF1). Ninety-two patients with MPNSTs, over a period of 20 years, were reviewed. A retrospective chart review was performed. The median age was 43.5 years (range, 3-84 years) and 55.4% were female; 41 patients (44.6%) had NF1-associated tumors. Mean tumor sizes were 15.8 ± 8.2 cm and 10.8 ± 6.3 cm for patients with and without NF1, respectively. Combined two- and five-year overall survival was 48.5% and 29%. Multivariate analysis confirmed the association of tumor size greater than 10 cm (hazard ratio (HR) 2.99; 95% confidence interval (CI) 1.14-7.85; p = 0.0258) and presence of NF1 (HR 3.41; 95%CI 1.88-6.19; p < 0.001) with a decreased overall survival. Tumor size and NF1 status were the most important predictors of overall survival in our population.

  9. Survivin expression and prognostic significance in pediatric malignant peripheral nerve sheath tumors (MPNST).

    PubMed

    Alaggio, Rita; Turrini, Riccardo; Boldrin, Daniela; Merlo, Anna; Gambini, Claudio; Ferrari, Andrea; Dall'igna, Patrizia; Coffin, Cheryl M; Martines, Annalisa; Bonaldi, Laura; De Salvo, Gian Luca; Zanovello, Paola; Rosato, Antonio

    2013-01-01

    Malignant peripheral nerve sheath tumors (MPNST) are very aggressive malignancies comprising approximately 5-10% of all soft tissue sarcomas. In this study, we focused on pediatric MPNST arising in the first 2 decades of life, as they represent one the most frequent non-rhabdomyosarcomatous soft tissue sarcomas in children. In MPNST, several genetic alterations affect the chromosomal region 17q encompassing the BIRC5/SURVIVIN gene. As cancer-specific expression of survivin has been found to be an effective marker for cancer detection and outcome prediction, we analyzed survivin expression in 35 tumor samples derived from young patients affected by sporadic and neurofibromatosis type 1-associated MPNST. Survivin mRNA and protein expression were assessed by Real-Time PCR and immunohistochemical staining, respectively, while gene amplification was analyzed by FISH. Data were correlated with the clinicopathological characteristics of patients. Survivin mRNA was overexpressed in pediatric MPNST and associated to a copy number gain of BIRC5; furthermore, increased levels of transcripts correlated with a higher FNCLCC tumor grade (grade 1 and 2 vs. 3, p = 0.0067), and with a lower survival probability (Log-rank test, p = 0.0038). Overall, these data support the concept that survivin can be regarded as a useful prognostic marker for pediatric MPNST and a promising target for therapeutic interventions.

  10. Poly (ADP) ribose polymerase inhibition: A potential treatment of malignant peripheral nerve sheath tumor.

    PubMed

    Kivlin, Christine M; Watson, Kelsey L; Al Sannaa, Ghadah A; Belousov, Roman; Ingram, Davis R; Huang, Kai-Lieh; May, Caitlin D; Bolshakov, Svetlana; Landers, Sharon M; Kalam, Azad Abul; Slopis, John M; McCutcheon, Ian E; Pollock, Raphael E; Lev, Dina; Lazar, Alexander J; Torres, Keila E

    2016-01-01

    Poly (ADP) ribose polymerase (PARP) inhibitors, first evaluated nearly a decade ago, are primarily used in malignancies with known defects in DNA repair genes, such as alterations in breast cancer, early onset 1/2 (BRCA1/2). While no specific mutations in BRCA1/2 have been reported in malignant peripheral nerve sheath tumors (MPNSTs), MPNST cells could be effectively targeted with a PARP inhibitor to drive cells to synthetic lethality due to their complex karyotype and high level of inherent genomic instability. In this study, we assessed the expression levels of PARP1 and PARP2 in MPNST patient tumor samples and correlated these findings with overall survival. We also determined the level of PARP activity in MPNST cell lines. In addition, we evaluated the efficacy of the PARP inhibitor AZD2281 (Olaparib) in MPNST cell lines. We observed decreased MPNST cell proliferation and enhanced apoptosis in vitro at doses similar to, or less than, the doses used in cell lines with established defective DNA repair genes. Furthermore, AZD2281 significantly reduced local growth of MPNST xenografts, decreased the development of macroscopic lung metastases, and increased survival of mice with metastatic disease. Our results suggest that AZD2281 could be an effective therapeutic option in MPNST and should be further investigated for its potential clinical use in this malignancy.

  11. Appropriate modulation of autophagy sensitizes malignant peripheral nerve sheath tumor cells to treatment with imatinib mesylate.

    PubMed

    Okano, Munehiro; Sakata, Naoki; Ueda, Satoshi; Takemura, Tsukasa

    2014-04-01

    Malignant peripheral nerve sheath tumor (MPNST), very rare in childhood, is a highly aggressive soft-tissue tumor. We experienced a case of a 7-year-old boy with MPNST who was treated with imatinib mesylate (imatinib) after the identification of platelet-derived growth factor receptor expression in his tumor. We were unable to observe clinical benefits of imatinib in this patient. Therefore, cellular reactions of imatinib were investigated in vitro using 3 MPNST cell lines. Imatinib induced cytotoxicity in vitro with variable IC50 values (11.7 to >30 μM). Induction of apoptosis was not a pivotal mechanism in the inhibitory effects. We found that the treatment of MPNST cell lines with imatinib induced autophagy. Suppression of the initiation of autophagy by 3-methyladenine or small interfering RNA (siRNA) against beclin-1 attenuated the imatinib-mediated cytotoxicity. In contrast, blocking the formation of autophagosomes or the development of autolysosomes using siRNA against microtubule-associated protein light chain 3B, bafilomycin A1, chloroquine, or an MEK1/2 inhibitor (U0126) enhanced the imatinib-induced cytotoxicity in MPNST cells. Our data showed that the imatinib-mediated autophagy can function as a cytotoxic mechanism and that appropriate modulation of autophagy may sensitize MPNST cells to imatinib, which in turn may be a novel therapeutic strategy for MPNST.

  12. Analyses on the misdiagnoses of 25 patients with unilateral optic nerve sheath meningioma

    PubMed Central

    Mao, Jun-Feng; Xia, Xiao-Bo; Tang, Xiang-Bo; Zhang, Xue-Yong; Wen, Dan

    2016-01-01

    AIM To investigate clinical features of optic nerve sheath meningioma (ONSM) that was misdiagnosed, and to find methods to reduce the misdiagnoses. METHODS Retrospective series study. Twenty-five misdisgnosed patients with unilateral ONSM were collected from Jan. 2008 to Jan. 2015 and the clinical records reviewed. RESULTS Patients were misdiagnosed with acute papillitis most frequently (n=17), immediately followed by optic atrophy (n=8), ischemic optic neuropathy (n=5), acute retrobulbar optic neuritis (n=5), optic disc vasculitis (n=3). For each patient, the minimum frequency of misdiagnoses was once and the maximum was 4 times. As for the lasting time of being misdiagnosed, the shortest was 1.5mo and the longest was 45mo. Twenty-one cases (84%) were once treated with glucocorticoids, and its side effects was found in seventeen patients. Twenty patients (80%) complained with varying degree of vision loss. When a definite diagnosis was made, sixteen cases (64%) showed slight exophthalmos and eighteen cases (72%) had the tubular ONSM. CONCLUSION ONSM without loss obvious exophthalmos is easily misdiagnosed in clinic, and for most of these ONSMs are tubular. PMID:27672598

  13. Transorbital sonographic evaluation of normal optic nerve sheath diameter in healthy volunteers in Bangladesh.

    PubMed

    Maude, Rapeephan R; Hossain, Md Amir; Hassan, Mahtab Uddin; Osbourne, Sophie; Sayeed, Katherine Langan Abu; Karim, Mohammed Rezaul; Samad, Rasheda; Borooah, Shyamanga; Dhillon, Bal; Day, Nicholas P J; Dondorp, Arjen M; Maude, Richard J

    2013-01-01

    Measurement of optic nerve sheath diameter (ONSD) by ultrasound is increasingly used as a marker to detect raised intracranial pressure (ICP). ONSD varies with age and there is no clear consensus between studies for an upper limit of normal. Knowledge of normal ONSD in a healthy population is essential to interpret this measurement. In a prospective observational study, ONSD was measured using a 15 MHz ultrasound probe in healthy volunteers in Chittagong, Bangladesh. The aims were to determine the normal range of ONSD in healthy Bangladeshi adults and children, compare measurements in males and females, horizontal and vertical beam orientations and left and right eyes in the same individual and to determine whether ONSD varies with head circumference independent of age. 136 subjects were enrolled, 12.5% of whom were age 16 or under. Median ONSD was 4.41 mm with 95% of subjects in the range 4.25-4.75 mm. ONSD was bimodally distributed. There was no relationship between ONSD and age (≥4 years), gender, head circumference, and no difference in left vs right eye or horizontal vs vertical beam. Ultrasonographic ONSD in Bangladeshi healthy volunteers has a narrow bimodal distribution independent of age (≥4 years), gender and head circumference. ONSD >4.75 mm in this population should be considered abnormal.

  14. Transorbital Sonographic Evaluation of Normal Optic Nerve Sheath Diameter in Healthy Volunteers in Bangladesh

    PubMed Central

    Maude, Rapeephan R.; Amir Hossain, Md; Hassan, Mahtab Uddin; Osbourne, Sophie; Sayeed, Katherine Langan Abu; Karim, Mohammed Rezaul; Samad, Rasheda; Borooah, Shyamanga; Dhillon, Bal; Day, Nicholas P. J.; Dondorp, Arjen M.; Maude, Richard J.

    2013-01-01

    Introduction Measurement of optic nerve sheath diameter (ONSD) by ultrasound is increasingly used as a marker to detect raised intracranial pressure (ICP). ONSD varies with age and there is no clear consensus between studies for an upper limit of normal. Knowledge of normal ONSD in a healthy population is essential to interpret this measurement. Methods In a prospective observational study, ONSD was measured using a 15 MHz ultrasound probe in healthy volunteers in Chittagong, Bangladesh. The aims were to determine the normal range of ONSD in healthy Bangladeshi adults and children, compare measurements in males and females, horizontal and vertical beam orientations and left and right eyes in the same individual and to determine whether ONSD varies with head circumference independent of age. Results 136 subjects were enrolled, 12.5% of whom were age 16 or under. Median ONSD was 4.41 mm with 95% of subjects in the range 4.25–4.75 mm. ONSD was bimodally distributed. There was no relationship between ONSD and age (≥4 years), gender, head circumference, and no difference in left vs right eye or horizontal vs vertical beam. Conclusions Ultrasonographic ONSD in Bangladeshi healthy volunteers has a narrow bimodal distribution independent of age (≥4 years), gender and head circumference. ONSD >4.75 mm in this population should be considered abnormal. PMID:24312515

  15. Survivin Expression and Prognostic Significance in Pediatric Malignant Peripheral Nerve Sheath Tumors (MPNST)

    PubMed Central

    Boldrin, Daniela; Merlo, Anna; Gambini, Claudio; Ferrari, Andrea; Dall'Igna, Patrizia; Coffin, Cheryl M.; Martines, Annalisa; Bonaldi, Laura; De Salvo, Gian Luca; Zanovello, Paola; Rosato, Antonio

    2013-01-01

    Malignant peripheral nerve sheath tumors (MPNST) are very aggressive malignancies comprising approximately 5–10% of all soft tissue sarcomas. In this study, we focused on pediatric MPNST arising in the first 2 decades of life, as they represent one the most frequent non-rhabdomyosarcomatous soft tissue sarcomas in children. In MPNST, several genetic alterations affect the chromosomal region 17q encompassing the BIRC5/SURVIVIN gene. As cancer-specific expression of survivin has been found to be an effective marker for cancer detection and outcome prediction, we analyzed survivin expression in 35 tumor samples derived from young patients affected by sporadic and neurofibromatosis type 1-associated MPNST. Survivin mRNA and protein expression were assessed by Real-Time PCR and immunohistochemical staining, respectively, while gene amplification was analyzed by FISH. Data were correlated with the clinicopathological characteristics of patients. Survivin mRNA was overexpressed in pediatric MPNST and associated to a copy number gain of BIRC5; furthermore, increased levels of transcripts correlated with a higher FNCLCC tumor grade (grade 1 and 2 vs. 3, p = 0.0067), and with a lower survival probability (Log-rank test, p = 0.0038). Overall, these data support the concept that survivin can be regarded as a useful prognostic marker for pediatric MPNST and a promising target for therapeutic interventions. PMID:24303016

  16. Poly (ADP) ribose polymerase inhibition: A potential treatment of malignant peripheral nerve sheath tumor

    PubMed Central

    Kivlin, Christine M.; Watson, Kelsey L.; Al Sannaa, Ghadah A.; Belousov, Roman; Ingram, Davis R.; Huang, Kai-Lieh; May, Caitlin D.; Bolshakov, Svetlana; Landers, Sharon M.; Kalam, Azad Abul; Slopis, John M.; McCutcheon, Ian E.; Pollock, Raphael E.; Lev, Dina; Lazar, Alexander J.; Torres, Keila E.

    2016-01-01

    ABSTRACT Poly (ADP) ribose polymerase (PARP) inhibitors, first evaluated nearly a decade ago, are primarily used in malignancies with known defects in DNA repair genes, such as alterations in breast cancer, early onset 1/2 (BRCA1/2). While no specific mutations in BRCA1/2 have been reported in malignant peripheral nerve sheath tumors (MPNSTs), MPNST cells could be effectively targeted with a PARP inhibitor to drive cells to synthetic lethality due to their complex karyotype and high level of inherent genomic instability. In this study, we assessed the expression levels of PARP1 and PARP2 in MPNST patient tumor samples and correlated these findings with overall survival. We also determined the level of PARP activity in MPNST cell lines. In addition, we evaluated the efficacy of the PARP inhibitor AZD2281 (Olaparib) in MPNST cell lines. We observed decreased MPNST cell proliferation and enhanced apoptosis in vitro at doses similar to, or less than, the doses used in cell lines with established defective DNA repair genes. Furthermore, AZD2281 significantly reduced local growth of MPNST xenografts, decreased the development of macroscopic lung metastases, and increased survival of mice with metastatic disease. Our results suggest that AZD2281 could be an effective therapeutic option in MPNST and should be further investigated for its potential clinical use in this malignancy. PMID:26650448

  17. Malignant peripheral nerve sheath tumor of the uterine corpus presenting as a huge abdominal neoplasm.

    PubMed

    Sengar Hajari, Anju Rani; Tilve, Arundhati G; Kulkarni, Jagdeesh N; Bharat, Rekhi

    2015-01-01

    A 45-year-old P3L3, referred to us with abdominopelvic mass for further management. Vaginal examination was suggestive of uterine mass. Magnetic resonance imaging. (MRI) of abdomen.pelvis disclosed a uterine mass with equivocal invasion of the fat plane with the sigmoid colon. Coelomic antigen. (CA) 125 was 120.2 U/ml. (normal range, 0-35 U/ml). On exploratory laparotomy entire pelvic cavity was filled with a mass that was seen arising from the uterus and involving the sigmoid colon. Hence, a total abdominal hysterectomy with bilateral salpingo-oopphorectomy. (TAH BSO) was performed, along with resection anastomosis of the rectosigmoid and excision of omental and pelvic peritoneal nodules. Histopathology and immunohistochemical analysis, including S100-P positivity confirmed diagnosis of a malignant peripheral nerve sheath tumor. (MPNST), with tumor deposits in the right parametrium, omentum, sigmoid colon, and pelvic peritoneum. This case is presented in view of its rarity and associated diagnostic and therapeutic implications.

  18. Histopathology and clinical outcome of NF1-associated vs. sporadic malignant peripheral nerve sheath tumors.

    PubMed

    Hagel, Christian; Zils, Ulrich; Peiper, Matthias; Kluwe, Lan; Gotthard, Stefan; Friedrich, Reinhard E; Zurakowski, David; von Deimling, Andreas; Mautner, Victor Felix

    2007-04-01

    The differences in the clinical course and histopathology of sporadic and neurofibromatosis type 1 (NF1)-associated malignant peripheral nerve sheath tumors (MPNST) were investigated retrospectively. The collective comprised 38 NF1 patients and 14 sporadic patients. NF1 patients were significantly younger at diagnosis (p<0.001) and had a significantly shorter survival time than sporadic patients (median survival 17 months vs. 42 months, Breslow p<0.05). The time interval to local recurrence and metastatic spread was also significantly shorter in NF1 patients (9.4 months vs. 30.0 months, p<0.01; 9.1 months vs. 33.2 months, p<0.001, respectively). In patients with the original histopathological data available (22 NF1 patients, 14 sporadic cases), NF1-associated MPNST showed a significantly higher cellularity compared to sporadic tumors (p<0.001) whereas sporadic MPNST featured a significantly higher pleomorphism (p<0.01). Most importantly, while histopathological variables correlated with French Fédération Nationale des Centres de Lutte Contre le Cancer grading in sporadic MPNST, this was not the case for NF1-associated tumors. The differences between NF1-associated and sporadic MPNST in regard to the clinical course and histopathology may reflect some fundamental differences in biology and pathomechanism of the two tumor groups. Our findings indicate the necessity for a separate grading scheme which takes into account the genetic background in NF1 patients.

  19. Primary uterine cervix melanoma resembling malignant peripheral nerve sheath tumor: a case report.

    PubMed

    Pusceddu, Sara; Bajetta, Emilio; Buzzoni, Roberto; Carcangiu, Maria Luisa; Platania, Marco; Del Vecchio, Michele; Ditto, Antonino

    2008-10-01

    A rare variant of malignant melanoma (MM) of the uterine cervix that mimics a malignant peripheral nerve sheath tumor (MPNST) is described. A 43-year-old white woman was admitted to the hospital complaining of genital discharge and vaginal bleeding. Neoadjuvant chemotherapy and total abdominal hysterectomy and bilateral salpingo-ovariectomy plus pelvic lymphadenectomy were performed, and the diagnosis was MPNST, FIGO IIB. Pathological examination showed a diffuse proliferation of amelanotic spindle cells and large, highly atypical, frequently multinucleated, bizarre, and S100-, HMB-45-, vimentin-positive cells. The patient remained disease-free for 43 months, when an abdominal computed tomographic scan showed local polypoid vaginal lesions, with histological features of typical MM. A pathological review was obtained in our institution by a gynecological pathologist, who defined the primary neoplasm in the cervix as an MM, with a pattern of growth histologically simulating an MPNST, metastatic to the vagina. To our knowledge, this is the first report in literature of MM of the uterine cervix resembling MPNST. Despite its rarity, this variant of MM should be considered when a diagnosis of cervix MPNST is made. The histological and immunohistochemical features of these different entities should be considered in the differential diagnosis.

  20. Molecular Heterogeneity of Canine Cutaneous Peripheral Nerve Sheath Tumors: A Drawback in the Diagnosis Refinement.

    PubMed

    Teixeira, Sílvia; Amorim, Irina; Rêma, Alexandra; Faria, Fátima; Gärtner, Fátima

    Peripheral nerve sheath tumors (PNSTs) belong to a very heterogeneous group of neoplasms occurring both in dogs and humans. The aim of the present study was to evaluate the histological and immunohistochemical features of canine cutaneous PNSTs contributing to further refine their diagnosis. The histopathological phenotype and biological behavior of 40 canine cutaneous PNSTs were evaluated and vimentin, S-100, glial fibrillary acidic protein (GFAP), neuron-specific enolase (NSE), desmin, alpha-smooth muscle actin (α-SMA) and Ki-67 immunoreactivity were assessed. Respectively, 17 and 23 lesions were classified as benign and malignant PNSTs. The malignant lesions were more often positive for S-100 and presented a proliferation index significantly higher when compared to the benign ones (p<0.05). The differential diagnosis of PNST on routine stained samples is difficult and the immunohistochemical examination may contribute to the final diagnosis. However, these lesions present a complex histogenesis and show very variable individual features; thus, an unequivocally immunohistochemical panel that could have supported the PNST diagnostic was not achieved. Nevertheless, we concluded that Ki-67 can be a useful marker helping to discriminate the biological behavior of canine PNST. Copyright © 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  1. [A rare case of nerve-sheath sarcoma with rhabdomyoblastic differentiation (malignant triton tumor)].

    PubMed

    Malerba, M; Garofalo, A

    2003-01-01

    Malignant peripheral nerve sheath tumors (MPNST) are spindle-cell sarcomas that appear in a setting of neurofibroma or schwannoma or are associated with peripheral nerves or demonstrate nerve sheath differentiation. Malignant triton tumor (MTT) is a subtype of MPNST that also contain tissue with skeletal muscle differentiation (embryonal, plemorphic and botryoid rhabdomyosarcoma). The estimated incidence of MPNSTs in patients with NF1 is 2-5% compared with 0.0001% in the general population and approximately 69% of the reported cases of MTT are associated with von Recklinghausen disease. In July 2002 a 37-year old man was readmitted to the Department of Oncologic Surgery of the S. Camillo-Forlanini Hospital in Rome for both a right-sided retroperitoneal paravertebral not palpable mass, incidentally detected at a follow-up MRI, and a left-sided popliteal mass, discovered at clinical evaluation. Seventeen months before, when the patient underwent surgery at the same Department for both a left-sided paravertebral inferior mediastinal neurofibroma and a right-sided axillary neurofibroma, diagnosis of von Recklinghausen disease (NF1) was made, according to the criteria established by the NIH Consensus Development. Conference on Neurofibromatosis of 1987. A xifopubic laparotomy was performed: the tumor appeared to be localized, well-capsulated and strictly associated to the lumbar and sacral nervous radicles (L4, L5, S1) without evidence of invasion. The tumor was completely resected with sparing of the psoas muscle and the lumbar plexus through a subperineural dissection technique. No intra-operative pathologic examination was performed. Postoperative pathologic findings showed evidence for a trition tumor. The popliteal mass was resected too and resulted to be a neurofibroma just like the tumors resected 17 months before when diagnosis of von Recklinghausen disease was made. The patient was disease free 6 months after initial surgery. Sarcoma arising in anatomic site

  2. Early decompression of the injured optic nerve reduces axonal degeneration and improves functional outcome in the adult rat.

    PubMed

    Ohlsson, Marcus; Svensson, Mikael

    2007-05-01

    The putative beneficial role of an early decompression of injured CNS tissue following trauma remains controversial. In this study, we approach this scientific query using a standardized injury of the optic nerve in adult rats. Adult Sprague-Dawley rats were subjected to a standardized optic nerve constriction injury by applying a loose ligature around the nerve for 5 min, 1, 6 or 24 h. All animals were sacrificed at 28 dpi. Viable axons distal to the injury were quantified using semithin sections, and regenerative fibers were studied using antisera to neurofilament and GAP43. Axonal degeneration and glial scar development were analyzed using Fluoro-Jade staining and anti-GFAP, respectively. Visual function was studied with visual evoked potentials (VEP). No significant differences were observed between 1 and 6 h of optic nerve compression. However, the number of viable axons analyzed with neurofilament and on semithin sections, decreased significantly between 6 and 24 h, paralleled by an increase in Fluoro-Jade labeled axonal debris (P < 0.001). GFAP-IR density was significantly higher (P < 0.001) in the 24 h compression group in comparison to 6 h. VEP showed preserved, but impaired visual function in animals subjected to compression up to 6 h, compared to an abolished cortical response at 24 h. Regenerative GAP43-positive sprouts were occasionally found distal to the lesion in animals subjected to compression up to 6 h, but not at 24 h. These findings suggest that early optic nerve decompression within hours after the initial trauma is beneficial for functional outcome.

  3. Does pain relief by CT-guided indirect cervical nerve root injection with local anesthetics and steroids predict pain relief after decompression surgery for cervical nerve root compression?

    PubMed

    Antoniadis, Alexander; Dietrich, Tobias J; Farshad, Mazda

    2016-10-01

    The relationship of pain relief from a recently presented CT-guided indirect cervical nerve root injection with local anesthetics and steroids to surgical decompression as a treatment for single-level cervical radiculopathy is not clear. This retrospective study aimed to compare the immediate and 6-week post-injection effects to the short- and long-term outcomes after surgical decompression, specifically in regard to pain relief. Patients (n = 39, age 47 ± 10 years) who had undergone CT-guided indirect injection with local anesthetics and steroids as an initial treatment for single cervical nerve root radiculopathy and who subsequently needed surgical decompression were included retrospectively. Pain levels (VAS scores) were monitored before, immediately after, and 6 weeks after injection (n = 34), as well as 6 weeks (n = 38) and a mean of 25 months (SD ± 12) after surgical decompression (n = 36). Correlation analysis was performed to find potential associations of pain relief after injection and after surgery to investigate the predictive value of post-injection pain relief. There was no correlation between immediate pain relief after injection (-32 ± 27 %) and 6 weeks later (-7 ± 19 %), (r = -0.023, p = 0.900). There was an association by tendency between immediate pain relief after injection and post-surgical pain relief at 6 weeks (-82 ± 27 %), (r = 0.28, p = 0.08). Pain relief at follow-up remained high at -70 ± 21 % and was correlated with the immediate pain amelioration effect of the injection (r = 0.37, p = 0.032). Five out of seven patients who reported no pain relief from injection had a pain relief from surgery in excess of 50 %. The amount of immediate radiculopathic pain relief after indirect cervical nerve root injection is associated with the amount of pain relief achieved at long-term follow-up after surgical decompression of single-level cervical radiculopathy

  4. Three-Dimensional Radiologic Study on Index Measurement of Endonasal Endoscopic Optic Nerve Decompression.

    PubMed

    Zhao, Yao; Duan, Haobo; Liu, Jianming; Cheng, Kailiang; Han, Yingying; Li, Youqiong

    2017-09-01

    To provide the radiologic basis for the clinical application of endonasal endoscopic optic nerve decompression (EEOND). CTA images were used to observe the optic canal (OC) and related structures of 60 patients (120 sides) with normal nasal, paranasal sinuses, OC, and other related structures. Optic canal could be classified as: the canal (10 sides, 8.33%), the semicanal (25 sides, 20.83%), the impression (49 sides, 40.83%), and the nonimpression (36 sides, 30%). According to its relationships with the sinuses, OC could be further typed as: ethmoid sinus (22 sides, 18.3%), sphenoid sinus (38 sides, 31.7%), ethmoid and sphenoid sinus (60 sides, 50%). The thickness of OC medial wall is about 1.11 ± 0.24 mm at orbital mouth, 0.87 ± 0.25 mm at middle part and 1.19 ± 0.27 mm at cranial mouth. The arc length of OC bone wall which can be opened from the sinus cavity is about 7.18 ± 0.76 mm at orbital mouth, 8.27 ± 0.93 mm at middle part, and 6.98 ± 0.89 mm at cranial mouth. The length of the OC medial wall is 12.18 ± 1.35 mm. In the three-dimensional Cartesian coordinate system that origined with the last point of middle turbinate root and oriented by temporal side, front side, and superior side, the coordinates of midpoints of OC medial wall are: (3.64 ± 1.11, 8.48 ± 1.65, 23.14 ± 2.67) at orbital mouth, (0.16 ± 1.21, 3.99 ± 1.80, 24.85 ± 2.67) at middle part, and (-3.59 ± 1.22, 0.77 ± 2.13, 26.39 ± 2.68) at cranial mouth. One length unit on the axes is a millimeter. Computed tomography (CT) scanning technique can measure the data of the OC in EEOND. It has great guiding significance for clinical operation.

  5. Reproducibility and accuracy of optic nerve sheath diameter assessment using ultrasound compared to magnetic resonance imaging

    PubMed Central

    2013-01-01

    Background Quantification of the optic nerve sheath diameter (ONSD) by transbulbar sonography is a promising non-invasive technique for the detection of altered intracranial pressure. In order to establish this method as follow-up tool in diseases with intracranial hyper- or hypotension scan-rescan reproducibility and accuracy need to be systematically investigated. Methods The right ONSD of 15 healthy volunteers (mean age 24.5 ± 0.8 years) were measured by both transbulbar sonography (9 – 3 MHz) and 3 Tesla MRI (half-Fourier acquisition single-shot turbo spin-echo sequences, HASTE) 3 and 5 mm behind papilla. All volunteers underwent repeated ultrasound and MRI examinations in order to assess scan-rescan reproducibility and accuracy. Moreover, inter- and intra-observer variabilities were calculated for both techniques. Results Scan-rescan reproducibility was robust for ONSD quantification by sonography and MRI at both depths (r > 0.75, p ≤ 0.001, mean differences < 2%). Comparing ultrasound- and MRI-derived ONSD values, we found acceptable agreement between both methods for measurements at a depth of 3 mm (r = 0.72, p = 0.002, mean difference < 5%). Further analyses revealed good inter- and intra-observer reliability for sonographic measurements 3 mm behind the papilla and for MRI at 3 and 5 mm (r > 0.82, p < 0.001, mean differences < 5%). Conclusions Sonographic ONSD quantification 3 mm behind the papilla can be performed with good reproducibility, measurement accuracy and observer agreement. Thus, our findings emphasize the feasibility of this technique as a non-invasive bedside tool for longitudinal ONSD measurements. PMID:24289136

  6. Radiation-Induced Malignant Peripheral Nerve Sheath Tumors: A Systematic Review.

    PubMed

    Yamanaka, Ryuya; Hayano, Azusa

    2017-09-01

    Radiation-induced malignant peripheral nerve sheath tumors (MPNSTs) are an uncommon late risk of irradiation. We conducted the largest systematic review to date of individual patient data for patients with these tumors. We conducted a systematic search using the PubMed database, and compiled a systematic literature review. We used Kaplan-Meier analysis and a log-rank test to estimate survival. We analyzed 65 radiation-induced and 26 radiation-associated MPNSTs in patients with neurofibromatosis. The mean ages of onset for primary lesions of the 2 types were 31.7 ± 18.2 and 17.1 ± 12.4 years, respectively (P = 0.0008). The latency periods between radiotherapy and onset of the 2 types of MPNSTs were 13.5 ± 7.8 and 11.8 ± 7.5 years, respectively (P = 0.3101). The median overall survival and 5-year survival were 11 months (6.8%) and 23 months (5.8%), respectively (P = 0.2168). Negative surgical margin and patient sex were variables retained for the prognosis of radiation-induced and radiation-associated MPNSTs. The prognosis of radiation-induced and radiation-associated MPNST was worse than that reported for de novo MPNSTs. Surgical complete resection is the mainstay for treatment of radiation-induced and radiation-associated MPNSTs. The risk of incidence of secondary MPNSTs in patients treated with radiotherapy warrants longer follow-up periods. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Confirmation of mutation landscape of NF1-associated malignant peripheral nerve sheath tumors.

    PubMed

    Sohier, Pierre; Luscan, Armelle; Lloyd, Angharad; Ashelford, Kevin; Laurendeau, Ingrid; Briand-Suleau, Audrey; Vidaud, Dominique; Ortonne, Nicolas; Pasmant, Eric; Upadhyaya, Meena

    2017-05-01

    The commonest tumors associated with neurofibromatosis type 1 (NF1) are benign peripheral nerve sheath tumors, called neurofibromas. Malignant transformation of neurofibromas into aggressive MPNSTs may occur with a poor patient prognosis. A cooperative role of SUZ12 or EED inactivation, along with NF1, TP53, and CDKN2A loss-of-function, has been proposed to drive progression to MPNSTs. An exome sequencing analysis of eight MPNSTs, one plexiform neurofibroma, and seven cutaneous neurofibromas was undertaken. Biallelic inactivation of the NF1 gene was observed in the plexiform neurofibroma and the MPNSTs, underlining that somatic biallelic NF1 inactivation is likely to be the initiating event for plexiform neurofibroma genesis, although it is unlikely to be sufficient for the subsequent MPNST development. The majority (5/8) of MPNSTs in our analyses demonstrated homozygous or heterozygous deletions of CDKN2A, which may represent an early event following NF1 LOH in the malignant transformation of Schwann cells from plexiform neurofibroma to MPNST. Biallelic somatic alterations of SUZ12 was also found in 4/8 MPNSTs. EED biallelic alterations were detected in 2 of the other four MPNSTs, with one tumor having a homozygous EED deletion. A missense mutation in the chromatin regulator KDM2B was also identified in one MPNST. No TP53 point mutations were found in this study, confirming previous data that TP53 mutations may be relatively rare in NF1-associated MPNSTs. Our study confirms the frequent biallelic inactivation of PRC2 subunits SUZ12 and EED in MPNSTs, and suggests the implication of KDM2B.

  8. Dissecting the roles of Ephrin-A3 in malignant peripheral nerve sheath tumor by TALENs.

    PubMed

    Wang, Zhengguang; Liu, Zhendong; Liu, Bo; Liu, Gengyan; Wu, Song

    2015-07-01

    Malignant peripheral nerve sheath tumor (MPNST) is a rare and aggressive soft tissue sarcoma for which effective treatments have not yet been established due to poor understanding of its pathogenesis. Our previous study indicated that miR-210-mediated Ephrin-A3 (EFNA3) promotion of proliferation and invasion of MPNST cells plays an important role in MPNST tumorigenesis and progression. The purpose of the present study was to further investigate the roles of EFNA3 in MPNST. Constructed transcription activator-like effector nucleases (TALENs) and lentiviral vectors were transfected into MPNST ST88-14 (NF1 wild-type) and sNF96.2 (NF1 mutant type) cell lines to obtain gain- and loss-of-function cell lines for the EFNA3 function study. The results showed that the knockout of ENFA3 increased cellular viability and invasiveness of the MPNST cells. However, the adhesion ability of MPNST cells was enhanced or inhibited when EFNA3 was overexpressed or knocked out, respectively. It was also observed that knockout of EFNA3 significantly decreased the expression of phosphorylated FAK (p-FAK) and the tumor necrosis factor α (TNF-α) compared to that in the control cells, yet the expression of phosphatidylinositol 3-kinase (PI3K), GTPase, integrins, vascular endothelial growth factor (VEGF) and hypoxia-inducible factor 1α (HIF-α) increased significantly. Inversely, overexpression of EFNA3 significantly increased the expression of p-FAK and TNF-α compared to that in the control cells, yet the expression of PI3K, GTPase, integrins, VEGF and HIF-α decreased significantly. The results indicated that EFNA3 serves as a tumor suppressor in MPNST cells and it may play a critical role in the focal adhesion kinase (FAK) signaling and VEGF-associated tumor angiogenesis pathway. These findings may not only facilitate the better understanding of MPNST pathogenesis, but also suggest EFNA3 as a promising target for MPNST treatment.

  9. Neurofibromin specific antibody differentiates malignant peripheral nerve sheath tumors (MPNST) from other spindle cell neoplasms.

    PubMed

    Reuss, David E; Habel, Antje; Hagenlocher, Christian; Mucha, Jana; Ackermann, Ulrike; Tessmer, Claudia; Meyer, Jochen; Capper, David; Moldenhauer, Gerhard; Mautner, Victor; Frappart, Pierre-Olivier; Schittenhelm, Jens; Hartmann, Christian; Hagel, Christian; Katenkamp, Kathrin; Petersen, Iver; Mechtersheimer, Gunhild; von Deimling, Andreas

    2014-04-01

    Malignant peripheral nerve sheath tumors (MPNST) derive from the Schwann cell or perineurial cell lineage and occur either sporadically or in association with the tumor syndrome neurofibromatosis type 1 (NF1). MPNST often pose a diagnostic challenge due to their frequent lack of pathognomonic morphological or immunohistochemical features. Mutations in the NF1 tumor suppressor gene are found in all NF1-associated and many sporadic MPNST. The presence of NF1 mutation may have the potential to differentiate MPNST from several morphologically similar neoplasms; however, mutation detection is hampered by the size of the gene and the lack of mutational hot spots. Here we describe a newly developed monoclonal antibody binding to the C-terminus of neurofibromin (clone NFC) which was selected for optimal performance in routinely processed formalin-fixed and paraffin-embedded tissue. NFC immunohistochemistry revealed loss of neurofibromin in 22/25 (88 %) of NF1-associated and 26/61 (43 %) of sporadic MPNST. There was a strong association of neurofibromin loss with deletions affecting the NF1 gene (P < 0.01). In a series of 256 soft tissue tumors of different histotypes NFC staining showed loss of neurofibromin in 2/8 myxofibrosarcomas, 2/12 (16 %) pleomorphic liposarcomas, 1/16 (6 %) leiomyosarcomas, and 4/28 (14 %) unclassified undifferentiated pleomorphic sarcomas. However, loss of neurofibromin was not observed in 22 synovial sarcomas, 27 schwannomas, 23 solitary fibrous tumors, 14 low-grade fibromyxoid sarcomas, 50 dedifferentiated liposarcomas, 27 myxoid liposarcomas, 13 angiosarcomas, 9 extraskeletal myxoid chondrosarcomas, and 7 epitheloid sarcomas. Immunohistochemistry using antibody NFC may substantially facilitate sarcoma research and diagnostics.

  10. Morphological spectrum of peripheral nerve sheath tumors: An insight into World Health Organization 2013 classification

    PubMed Central

    Chikkannaiah, Panduranga; Boovalli, Mythri M.; Nathiyal, Velusamy; Venkataramappa, Srinivasamurthy

    2016-01-01

    Introduction: Peripheral nerve sheath tumors (PNSTs) are neuroectodermal in origin. Now these tumors are classified under World Health Organization (WHO) classification of tumors of soft tissue and bone 2013. Objective: To study the morphological spectrum of PNST and to study the secondary degenerative changes associated with it. Materials and Methods: This study was conducted from January 2010 to June 2015. The gross details of tumor and patient's demographic profiles were reviewed. The hematoxylin and eosin stained slides were reassessed and the lesions were categorized and classified as per the WHO 2013 classification. The tumors were also assessed for secondary degenerative changes. Results: Our study comprised 143 cases of PNST. Age of the patients ranged from 5 to 75 years. 21–30 years is the most common age of occurrence with head and neck being the most common site. The PNSTs observed in the present study were neurofibroma (NF) (61.5%), schwannoma (36%), malignant PNST (2%), and granular cell tumor (0.5%). Nearly 10% of NF fulfilled the criteria for neurofibromatosis 1 (NF1). Rare tumors such as plexiform schwannoma and granular cell tumor were also observed. Malignant tumors were larger in dimension than benign. Myxoid, cystic, and hyaline changes were commonly associated with benign tumors while necrosis, hemorrhage, and mitotic activity were seen with malignant tumors. Conclusion: This series highlights the pathological variants of PNST along with their morphological changes and NF1 association. It is essential to be familiar with all these variants of PNST for accurate diagnosis as they have varied biological behavior. PMID:27365950

  11. Intrathoracic peripheral nerve sheath tumors-a clinicopathological study of 75 cases.

    PubMed

    Boland, Jennifer M; Colby, Thomas V; Folpe, Andrew L

    2015-03-01

    Although peripheral nerve sheath tumors (PNSTs) are common in the posterior mediastinum, they are rare in other mediastinal compartments and in the pleuropulmonary parenchyma. We sought to characterize the clinicopathological features of PNSTs occurring in the lung, pleura, and mediastinum. Diagnoses were confirmed by slide review. Study cases include 21 benign pleuropulmonary PNSTs, 49 benign mediastinal PNSTs, and 5 malignant PNSTs. Benign pleuropulmonary tumors comprised 13 schwannomas, 6 neurofibromas, 1 perineurioma, and 1 ganglioneuroma. Six lesions were endobronchial (3 neurofibromas, 1 schwannoma, 1 perineurioma, 1 ganglioneuroma), whereas the remaining schwannomas and neurofibromas formed parenchymal masses (usually pleural based). Benign mediastinal PNSTs (46 posterior, 2 middle, and 1 anterior) were all schwannomas and showed a female predominance. None of the patients with benign PNSTs experienced recurrence. Of the 5 malignant PNSTs, 4 were pleuropulmonary (3 pleural based) and 1 occurred in the anterior mediastinum. Two of the 5 patients had a history of neurofibromatosis type 1 (aged 27 and 45 years). At last follow-up, 3 of the 5 patients had died of disease, 1 was alive with disease, and 1 was alive with no evidence of disease (41 months). Although rare, a wide histologic range of PNSTs occur in the lung. Although neurofibroma, perineurioma, and ganglioneuroma were observed as endobronchial lesions, most pulmonary schwannomas were pleural-based masses. Mediastinal PNSTs are dominated by posterior mediastinal schwannomas, although schwannomas rarely occur in the other mediastinal compartments as well. Malignant PNSTs are very rare in the thorax, where they show aggressive behavior. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Astounding recovery after resection of an intradural nerve sheath tumor in an adult male from Vietnam

    PubMed Central

    King, Paul; Khan, Saleen; Inamullah, Ovais

    2015-01-01

    Background: Spinal cord tumors can be classified as intramedullary, intradural extramedullary, or extradural. The differential diagnosis of spinal cord tumors includes meningiomas, astrocytomas, ependymomas, metastasis, nerve sheath tumors such as schwannomas or neurofibromas, and multiple sclerosis plaques. Radiology can provide clues to the type of tumor, but a pathology evaluation of a specimen is necessary to provide an accurate diagnosis. These tumors can cause a variety of neurological symptoms from spinal cord compression including pain, weakness, and paresthesia. They are treated by surgical resection, with a variety of outcomes possible depending on the severity of the preoperative symptoms, location and extent of the tumor, and efficacy of the surgery performed. Case Description: A 59-year-old male from Vietnam came to the Atlanta Medical Center for evaluation of severe ride sided hemiparesis and paresthesias. He first noticed alterations in his handwriting and quickly deteriorated to the point of being unable to walk or move his right arm. A cervical spinal mass was identified and analyzed on magnetic resonance imaging. Surgical resection was performed under a microscope in a joint operation between an orthopedic surgeon and neurosurgeon. A specimen of the tumor was sent to pathology for further evaluation. Conclusion: The mass was determined to be an intradural extramedullary schwannoma. The severity of the patient's symptoms and the location and size of the tumor made full recovery unlikely and postoperative quadriplegia a real possibility. The tumor was surgically resected, which led surprisingly, however, to a full and prompt resolution of the patient's symptoms. Less than 2 weeks after surgery, the patient was able to walk and had almost fully regained use of his hands. PMID:26425395

  13. Noninvasive and quantitative intracranial pressure estimation using ultrasonographic measurement of optic nerve sheath diameter

    PubMed Central

    Wang, Li-juan; Yao, Yan; Feng, Liang-shu; Wang, Yu-zhi; Zheng, Nan-nan; Feng, Jia-chun; Xing, Ying-qi

    2017-01-01

    We aimed to quantitatively assess intracranial pressure (ICP) using optic nerve sheath diameter (ONSD) measurements. We recruited 316 neurology patients in whom ultrasonographic ONSD was measured before lumbar puncture. They were randomly divided into a modeling and a test group at a ratio of 7:3. In the modeling group, we conducted univariate and multivariate analyses to assess associations between ICP and ONSD, age, sex, BMI, mean arterial blood pressure, diastolic blood pressure. We derived the mathematical function “Xing & Wang” from the modelling group to predict ICP and evaluated the function in the test group. In the modeling group, ICP was strongly correlated with ONSD (r = 0.758, p < 0.001), and this association was independent of other factors. The mathematical function was ICP = −111.92 + 77.36 × ONSD (Durbin-Watson value = 1.94). In the test group, a significant correlation was found between the observed and predicted ICP (r = 0.76, p < 0.001). Bland-Altman analysis yielded a mean difference between measurements of −0.07 ± 41.55 mmH2O. The intraclass correlation coefficient and its 95%CIs for noninvasive ICP assessments using our prediction model was 0.86 (0.79–0.90). Ultrasonographic ONSD measurements provide a potential noninvasive method to quantify ICP that can be conducted at the bedside. PMID:28169341

  14. Clinical outcomes after decompression of the nerve to the teres minor in patients with idiopathic isolated teres minor fatty atrophy.

    PubMed

    Kruse, Lisa M; Yamaguchi, Ken; Keener, Jay D; Chamberlain, Aaron M

    2015-04-01

    The purpose of this manuscript is to describe what we believe to be the first series of patients surgically treated for idiopathic isolated teres minor atrophy and to present the results of surgical decompression of the nerve to the teres minor. This is a retrospective cohort of 22 patients who underwent decompression of the nerve to the teres minor for isolated teres minor atrophy. Clinical data including duration of symptoms, additional diagnoses, concurrent procedures, preoperative physical examination findings, imaging data, and preoperative visual analog scale (VAS), Simple Shoulder Test (SST), and American Shoulder and Elbow Surgeons (ASES) scores were collected from the medical record. Postoperative patient-based clinical outcome measures including VAS, SST, and ASES scores were obtained during clinical examination or by telephone interview. Average length of follow-up was 26 months. Nine patients had concurrent procedures performed. Preoperatively, 12 of 14 (86%) had external rotation weakness in Hornblower's position. Postoperatively, pain scores decreased an average of 4 points; ASES scores increased 31.7 ± 20.2 points; SST scores increased 3.1 ± 2.3 points. No external rotation weakness was noted postoperatively in any tested patient. Two patients developed adhesive capsulitis. No other complications occurred. Isolated compression of the nerve to the teres minor is a rare and novel clinical entity. In properly selected cases, open release of the fascial sling enveloping the nerve branches to the teres minor can provide relief of symptoms and clinical improvement. Copyright © 2015 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  15. Direct Surgery of Previously Coiled Large Internal Carotid Ophthalmic Aneurysm for the Purpose of Optic Nerve Decompression

    PubMed Central

    Kawabata, Shuhei; Toyota, Shingo; Kumagai, Tetsuya; Goto, Tetsu; Mori, Kanji; Taki, Takuyu

    2017-01-01

    Background Progressive visual loss after coil embolization of a large internal carotid ophthalmic aneurysm has been widely reported. It is generally accepted that the primary strategy for this complication should be conservative, including steroid therapy; however, it is not well known as to what approach to take when the conservative therapy is not effective. Case Presentation We report a case of a 55-year-old female presenting with progressive visual loss after the coiling of a ruptured large internal carotid ophthalmic aneurysm. As the conservative therapy had not been effective, we performed neck clipping of the aneurysm with optic canal unroofing, anterior clinoidectomy, and partial removal of the embolized coils for the purpose of optic nerve decompression. After the surgery, the visual symptom was improved markedly. Conclusions It is suggested that direct surgery for the purpose of optic nerve decompression may be one of the options when conservative therapy is not effective for progressive visual disturbance after coil embolization. PMID:28229036

  16. Pain Relief and Health-Related Quality-of-Life Improvement After Microsurgical Decompression of Entrapped Peripheral Nerves in Patients With Painful Diabetic Peripheral Neuropathy.

    PubMed

    Yang, Wenqiang; Guo, Zhuangli; Yu, Yanbing; Xu, Jun; Zhang, Li

    Surgery had been shown to be effective for superimposed peripheral nerve entrapment syndrome in patients with diabetic peripheral neuropathy (DPN), with pain relief and sensation restored. Few studies, however, have reported the quality-of-life outcomes of surgery for the treatment of painful DPN (PDPN). The objective of the present study was to evaluate the effects of microsurgical decompression of multiple entrapped peripheral nerves on pain and health-related quality of life in patients with refractory PDPN of the lower limbs. Eleven patients with intractable PDPN of the lower limbs were recruited for the present study. All the patients underwent microsurgical decompression of the common peroneal nerve, deep peroneal nerve, and posterior tibial nerve. The pain intensity was assessed using the visual analog scale and health-related quality of life was measured using the short-form 36-item quality-of-life survey. Six (54.6%) patients experienced >50% pain relief (both daytime pain and nocturnal pain) at 2 weeks after the decompression procedure and 8 (72.7%) patients at 24 months postoperatively. Two (18.2%) patients experienced a >50% decrease in peak pain at the 2 weeks after the procedure and 8 (72.7%) patients at 24 months. Additionally, the scores from the short-form 36-item quality-of-life survey were significantly improved in the following 2 domains: bodily pain and general health at 2 weeks after the decompression procedure. Also, at 24 months postoperatively, 6 domains had significantly improved, including physical function, bodily pain, general health, social function, role emotional, and mental health. No significant side effects were recorded during the study. Microsurgical decompression of peripheral nerves is an effective and safe therapy for intractable PDPN with superimposed nerve compression.

  17. Use of T2-weighted magnetic resonance imaging of the optic nerve sheath to detect raised intracranial pressure

    PubMed Central

    Geeraerts, Thomas; Newcombe, Virginia FJ; Coles, Jonathan P; Abate, Maria Giulia; Perkes, Iain E; Hutchinson, Peter JA; Outtrim, Jo G; Chatfield, Dot A; Menon, David K

    2008-01-01

    Introduction The dural sheath surrounding the optic nerve communicates with the subarachnoid space, and distends when intracranial pressure is elevated. Magnetic resonance imaging (MRI) is often performed in patients at risk for raised intracranial pressure (ICP) and can be used to measure precisely the diameter of optic nerve and its sheath. The objective of this study was to assess the relationship between optic nerve sheath diameter (ONSD), as measured using MRI, and ICP. Methods We conducted a retrospective blinded analysis of brain MRI images in a prospective cohort of 38 patients requiring ICP monitoring after severe traumatic brain injury (TBI), and in 36 healthy volunteers. ONSD was measured on T2-weighted turbo spin-echo fat-suppressed sequence obtained at 3 Tesla MRI. ICP was measured invasively during the MRI scan via a parenchymal sensor in the TBI patients. Results Measurement of ONSD was possible in 95% of cases. The ONSD was significantly greater in TBI patients with raised ICP (>20 mmHg; 6.31 ± 0.50 mm, 19 measures) than in those with ICP of 20 mmHg or less (5.29 ± 0.48 mm, 26 measures; P < 0.0001) or in healthy volunteers (5.08 ± 0.52 mm; P < 0.0001). There was a significant relationship between ONSD and ICP (r = 0.71, P < 0.0001). Enlarged ONSD was a robust predictor of raised ICP (area under the receiver operating characteristic curve = 0.94), with a best cut-off of 5.82 mm, corresponding to a negative predictive value of 92%, and to a value of 100% when ONSD was less than 5.30 mm. Conclusions When brain MRI is indicated, ONSD measurement on images obtained using routine sequences can provide a quantitative estimate of the likelihood of significant intracranial hypertension. PMID:18786243

  18. Giant malignant peripheral nerve sheath tumor of thigh in an adolescent with neurofibromatosis type 1: a case report

    PubMed Central

    Tosun, Hacı Bayram; Serbest, Sancar; Turk, Bilge Aydın; Gumustas, Seyit Ali; Uludag, Abuzer

    2015-01-01

    Malignant peripheral nerve sheath tumors (MPNSTs) are rare sarcomas of children and adolescents, and they are aggressive tumors with a high rate of local recurrence. We present a 15-year-old boy with neurofibromatosis type 1 (NF1), who had a giant MPNST on the right thigh taking into account the available literature. Diagnosis of MPNST may be delayed in NF1 patients due to confusion with a neurofibroma and/or a plexiform neurofibroma. Malignancy should be considered, especially in cases with big masses, with heterogeneous involvement, or in the presence of cysts or necrotic nodules. The aim of surgical treatment is complete surgical excision. PMID:26604833

  19. Ultrasonographic measurement of optic nerve sheath diameter: A point of care test helps in prognostication of Intensive Care Unit patients

    PubMed Central

    Banerjee, Arnab; Bala, Renu; Saini, Savita

    2017-01-01

    Early identification of elevated intracranial pressure (ICP) is critical to ensuring timely and appropriate management to improve patient outcome. Measurement of the optic nerve sheath diameter by ultrasound is a well studied modality for noninvasive assessment of ICP. Recent studies have shown it to correlate with invasively measured ICP. We utilized this technique in our ICU and found it to be of great help in guiding patient management and predicting the prognosis. A case series of four patients is reported illustrating its utility in ICU patients. PMID:28405042

  20. Microneurolysis and decompression of long thoracic nerve injury are effective in reversing scapular winging: Long-term results in 50 cases

    PubMed Central

    Nath, Rahul K; Lyons, Andrew B; Bietz, Gabriel

    2007-01-01

    Background Long thoracic nerve injury leading to scapular winging is common, often caused by closed trauma through compression, stretching, traction, direct extrinsic force, penetrating injury, or neuritides such as Parsonage-Turner syndrome. We undertook the largest series of long thoracic nerve decompression and neurolysis yet reported to demonstrate the usefulness of long thoracic nerve decompression. Methods Winging was bilateral in 3 of the 47 patients (26 male, 21 female), yielding a total of 50 procedures. The mean age of the patients was 33.4 years, ranging from 24–57. Causation included heavy weight-lifting (31 patients), repetitive throwing (5 patients), deep massage (2 patients), repetitive overhead movement (1 patient), direct trauma (1 patient), motor bike accident (1 patient), and idiopathic causes (9 patients). Decompression and microneurolysis of the long thoracic nerve were performed in the supraclavicular space. Follow-up (average of 25.7 months) consisted of physical examination and phone conversations. The degree of winging was measured by the operating surgeon (RKN). Patients also answered questions covering 11 quality-of-life facets spanning four domains of the World Health Organization Quality of Life questionnaire. Results Thoracic nerve decompression and neurolysis improved scapular winging in 49 (98%) of the 50 cases, producing "good" or "excellent" results in 46 cases (92%). At least some improvement occurred in 98% of cases that were less than 10 years old. Pain reduction through surgery was good or excellent in 43 (86%) cases. Shoulder instability affected 21 patients preoperatively and persisted in 5 of these patients after surgery, even in the 5 patients with persistent instability who experienced some relief from the winging itself. Conclusion Surgical decompression and neurolysis of the long thoracic nerve significantly improve scapular winging in appropriate patients, for whom these techniques should be considered a primary

  1. Endoscopic Intermetatarsal Ligament Decompression.

    PubMed

    Lui, Tun Hing

    2015-12-01

    Morton neuroma is an entrapment of the intermetatarsal nerve by the deep intermetatarsal ligament. It is usually treated conservatively. Surgery is considered if there is recalcitrant pain that is resistant to conservative treatment. The surgical options include resection of the neuroma or decompression of the involved nerve. Decompression of the nerve by release of the intermetatarsal ligament can be performed by either an open or minimally invasive approach. We describe 2-portal endoscopic decompression of the intermetatarsal nerve. The ligament is released by a retrograde knife through the toe-web portal under arthroscopic guidance through the plantar portal.

  2. [Usefulness of extradural optic canal unroofing and decompression of the optic nerve for improvement of visual acuity in traumatic optic neuropathy].

    PubMed

    Nishida, Sho; Otani, Naoki; Inaka, Yasufumi; Morinaga, Yusuke; Kimura, Shohei; Tomura, Satoshi; Osada, Hideo; Harimoto, Kohzou; Takeuchi, Masaru; Wada, Kojiro; Mori, Kentaro

    2014-11-01

    An 81-year-old man presented with poor visual acuity of the left eye, swelling of the left eyelid, and elevation of the left intraocular pressure after contusion of the left palpebral portion. CT revealed left ocular proptosis and left intraorbital hematoma. Traumatic optic neuropathy was suspected, and emergent optic nerve decompression was performed through extradural anterior clinoidectomy followed by optic canal release. Postoperatively, his left visual acuity was markedly improved and the elevated intraocular pressure decreased. Postoperative CT demonstrated improvement of the left ocular proptosis and decompression of the optic nerve. Emergent optic canal release has been recommended in patients who have suffered visual dysfunction caused by optic canal fracture or intraorbital hematoma. The advantages of extradural anterior clinoidectomy followed by optic canal release include a shorter surgical route and easy identification of the optic nerve, resulting in fewer surgical complications. In addition, this procedure can achieve intraorbital decompression. We recommend extradural anterior clinoidectomy followed by optic canal release as a safe and reliable procedure for optic nerve decompression in patients with traumatic optic neuropathy.

  3. Rexin-G®, a tumor-targeted retrovector for malignant peripheral nerve sheath tumor: A case report

    PubMed Central

    Kim, Seth; Federman, Noah; Gordon, Erlinda M.; Hall, Frederick L.; Chawla, Sant P.

    2017-01-01

    Soft tissue sarcoma is a rare neoplasm of mesenchymal origin, accounting for only ~1% of all adult cancers and consisting of 75 histological subtypes. In the present report, the unique case of a 14 year-old female with metastatic malignant peripheral nerve sheath tumor (formerly, malignant melanotic schwannoma) of the parotid gland, who experienced a durable response and sustained tumor control with Rexin-G®, a tumor-targeted retroviral expression vector encoding an anti-cyclin G1 construct, is described. Post-parotidectomy, and prior to the administration of Rexin-G®, the patient received various chemotherapy regimens, including doxorubicin, ifosfamide, temozolomide, sorafenib, and an immunological therapy with interleukin-2, which only resulted in the further progression of lung metastases. The patient subsequently participated in a Phase 1/2 gene therapy study, during which she received intravenous Rexin-G® as monotherapy for two years with minimal drug-associated adverse events. Currently, the patient has no evidence of active disease 9 years after commencing the Rexin-G® treatment, and with no additional anti-cancer therapy. In conclusion, Rexin-G® may be a viable therapeutic option for malignant peripheral nerve sheath tumors, and should be further investigated in prospective histology-specific clinical trials for this type, and possibly other types, of chemotherapy-resistant sarcoma. PMID:28588778

  4. Clinical results of endoscopic sciatic nerve decompression for deep gluteal syndrome: mean 2-year follow-up.

    PubMed

    Park, Myung-Sik; Yoon, Sun-Jung; Jung, Sung-Yeop; Kim, Seung-Ho

    2016-05-20

    The purpose of this study is to assess the effectiveness of endoscopic sciatic nerve decompression and evaluated the differences of clinical results between atraumatic and traumatic groups. Sixty consecutive patients. We retrospectively reviewed sixty consecutive patients without major trauma (45 hips) or with major trauma (15 hips) groups to compare the outcomes of endoscopic treatment.). The mean follow-up period was 24 ± 2.6 months (range, 24-38.4 months). The mean duration of symptoms was 14.1 months (range, 12 to 32 months). Compromising structures were piriformis muscle, fibrovascular bundles, and adhesion with scar tissues. The mean VAS score for pain decreased from 7.4 ± 1.5 to 2.6 ± 1.5 (P = .001). The mean mHHS increased from 81.7 ± 9.6 to 91.8 ± 7.6 (P = .003). Clinically, positive paresthesia and seated piriformis test were statistically significant to diagnosis sciatic entrapment syndrome. Paresthesia and sitting pain were significantly improved at the final follow-up (P = .002). More favorable outcome was observed a group without major trauma. No complication was observed. Endoscopic sciatic nerve decompression is a safe and effective procedure for the management of DGS. Patients with major trauma could have poor clinical outcome. Seated piriformis test, FADIR, and tenderness of sciatic notch are maybe useful guide for pre and postoperative evaluation of DGS.

  5. Predictive Factors for Vision Recovery after Optic Nerve Decompression for Chronic Compressive Neuropathy: Systematic Review and Meta-Analysis

    PubMed Central

    Carlson, Andrew P.; Stippler, Martina; Myers, Orrin

    2012-01-01

    Objectives Surgical optic nerve decompression for chronic compressive neuropathy results in variable success of vision improvement. We sought to determine the effects of various factors using meta-analysis of available literature. Design Systematic review of MEDLINE databases for the period 1990 to 2010. Setting Academic research center. Participants Studies reporting patients with vision loss from chronic compressive neuropathy undergoing surgery. Main outcome measures Vision outcome reported by each study. Odds ratios (ORs) and 95% confidence intervals (CIs) for predictor variables were calculated. Overall odds ratios were then calculated for each factor, adjusting for inter study heterogeneity. Results Seventy-six studies were identified. Factors with a significant odds of improvement were: less severe vision loss (OR 2.31[95% CI = 1.76 to 3.04]), no disc atrophy (OR 2.60 [95% CI = 1.17 to 5.81]), smaller size (OR 1.82 [95% CI = 1.22 to 2.73]), primary tumor resection (not recurrent) (OR 3.08 [95% CI = 1.84 to 5.14]), no cavernous sinus extension (OR 1.88 [95% CI = 1.03 to 3.43]), soft consistency (OR 4.91 [95% CI = 2.27 to 10.63]), presence of arachnoid plane (OR 5.60 [95% CI = 2.08 to 15.07]), and more extensive resection (OR 0.61 [95% CI = 0.4 to 0.93]). Conclusions Ophthalmologic factors and factors directly related to the lesion are most important in determining vision outcome. The decision to perform optic nerve decompression for vision loss should be made based on careful examination of the patient and realistic discussion regarding the probability of improvement. PMID:24436885

  6. Epithelioid Malignant Peripheral Nerve Sheath Tumor Arising in a Schwannoma, in a Patient with “Neuroblastoma-like” Schwannomatosis and a Novel Germline SMARCB1 mutation

    PubMed Central

    Carter, Jodi M.; O'Hara, Carolyn; Dundas, George; Gilchrist, Dawna; Collins, Mark S.; Eaton, Katherine; Judkins, Alexander R.; Biegel, Jaclyn A.; Folpe, Andrew L.

    2011-01-01

    Epithelioid malignant peripheral nerve sheath tumors arising in pre-existing schwannomas are extremely rare. We report an unusual example occurring in a patient with multiple schwannomas (schwannomatosis), all but one of which showed “neuroblastoma-like” histology. By immunohistochemistry, both the epithelioid malignant peripheral nerve sheath tumor and the schwannomas showed a complete loss of the Smarcb1 protein. Subsequent genetic evaluation revealed the presence of a novel germline mutation in the SMARCB1/INI1 gene in the patient and three of her children, two of whom were diagnosed with atypical teratoid/rhabdoid tumors of the brain. PMID:22082606

  7. Decompression of the tympanic and labyrinthine segments of the facial nerve by middle cranial fossa approach: an anatomic study.

    PubMed

    da Franca Pereira, Marcos Alexandre; Bittencourt, Aline Gomes; de Andrade, Emerson Magno; Bento, Ricardo Ferreira; de Brito, Rubens

    2016-06-01

    Peripheral facial palsy is characterized by the permanent or temporary interruption of facial muscle function. The middle cranial fossa (MCF) approach has been used to decompress the facial nerve (FN) when hearing needs to be preserved. In this work, we describe a technique for decompressing the FN through the MCF approach, which allows the direct exposure of the labyrinthine and entire tympanic segment of the FN, with preservation of inner ear function. Twenty cadavers heads were used in this study. The reference landmarks used were the middle meningeal artery, greater superficial petrosal nerve, arcuate eminence, inferior petrosal sinus and meatal plane following the petrous apex from its most anterior and medial portion. The tympanic segment of the FN presented, on average, a total length of 11 ± 0.67 mm to the right and 11.5 ± 0.60 mm to the left. The longitudinal lengths of the bone window in the tegmen tympani were 16.8 ± 1.67 mm to the right and 16.8 ± 1.20 mm to the left. The cross-sectional lengths of the bone window in the tegmen tympani were 5.5 ± 1.20 mm and 5.0 ± 1.75 mm to the right and left sides, respectively. The average value of the elliptical area formed by the longitudinal and transversal lengths of the bone window made in the tegmen tympani was 72.5 ± 22.5 mm(2) to the right and 65.9 ± 30.3 mm(2) to the left. The proposed technique can be used for the surgical decompression of the tympanic, labyrinthine and meatal segments of the FN through the MCF in addition to reducing the surgical time and the risk to patients.

  8. Verticillin A Inhibits Leiomyosarcoma and Malignant Peripheral Nerve Sheath Tumor Growth via Induction of Apoptosis

    PubMed Central

    Zewdu, A; Lopez, G; Braggio, D; Kenny, C; Constantino, D; Bid, HK; Batte, K; Iwenofu, OH; Oberlies, NH; Pearce, CJ; Strohecker, AM; Lev, D; Pollock, RE

    2017-01-01

    Objective The heterogeneity of soft tissue sarcoma (STS) represents a major challenge for the development of effective therapeutics. Comprised of over 50 different histology subtypes of various etiologies, STS subsets are further characterized as either karyotypically simple or complex. Due to the number of genetic anomalies associated with genetically complex STS, development of therapies demonstrating potency against this STS cluster is especially challenging and yet greatly needed. Verticillin A is a small molecule natural product with demonstrated anticancer activity; however, the efficacy of this agent has never been evaluated in STS. Therefore, the goal of this study was to explore verticillin A as a potential STS therapeutic. Methods We performed survival (MTS) and clonogenic analyses to measure the impact of this agent on the viability and colony formation capability of karyotypically complex STS cell lines: malignant peripheral nerve sheath tumor (MPNST) and leiomyosarcoma (LMS). The in vitro effects of verticillin A on apoptosis were investigated through annexin V/PI flow cytometry analysis and by measuring fluorescently-labeled cleaved caspase 3/7 activity. The impact on cell cycle progression was assessed via cytometric measurement of propidium iodide intercalation. In vivo studies were performed using MPNST xenograft models. Tumors were processed and analyzed using immunohistochemistry (IHC) for verticillin A effects on growth (Ki67) and apoptosis (cleaved caspase 3). Results Treatment with verticillin A resulted in decreased STS growth and an increase in apoptotic levels after 24 h. 100 nM verticillin A induced significant cellular growth abrogation after 24 h (96.7, 88.7, 72.7, 57, and 39.7% reduction in LMS1, S462, ST88, SKLMS1, and MPNST724, respectively). We observed no arrest in cell cycle, elevated annexin, and a nearly two-fold increase in cleaved caspase 3/7 activity in all MPNST and LMS cell lines. Control normal human Schwann (HSC) and

  9. 3D Computer graphics simulation to obtain optimal surgical exposure during microvascular decompression of the glossopharyngeal nerve.

    PubMed

    Hiraishi, Tetsuya; Matsushima, Toshio; Kawashima, Masatou; Nakahara, Yukiko; Takahashi, Yuichi; Ito, Hiroshi; Oishi, Makoto; Fujii, Yukihiko

    2013-10-01

    The affected artery in glossopharyngeal neuralgia (GPN) is most often the posterior inferior cerebellar artery (PICA) from the caudal side or the anterior inferior cerebellar artery (AICA) from the rostral side. This technical report describes two representative cases of GPN, one with PICA as the affected artery and the other with AICA, and demonstrates the optimal approach for each affected artery. We used 3D computer graphics (3D CG) simulation to consider the ideal transposition of the affected artery in any position and approach. Subsequently, we performed microvascular decompression (MVD) surgery based on this simulation. For PICA, we used the transcondylar fossa approach in the lateral recumbent position, very close to the prone position, with the patient's head tilted anteriorly for caudal transposition of PICA. In contrast, for AICA, we adopted a lateral suboccipital approach with opening of the lateral cerebellomedullary fissure, to visualize better the root entry zone of the glossopharyngeal nerve and to obtain a wide working space in the cerebellomedullary cistern, for rostral transposition of AICA. Both procedures were performed successfully. The best surgical approach for MVD in patients with GPN is contingent on the affected artery--PICA or AICA. 3D CG simulation provides tailored approach for MVD of the glossopharyngeal nerve, thereby ensuring optimal surgical exposure.

  10. Constructing a statistical atlas of the radii of the optic nerve and cerebrospinal fluid sheath in young healthy adults

    NASA Astrophysics Data System (ADS)

    Harrigan, Robert L.; Plassard, Andrew J.; Mawn, Louise A.; Galloway, Robert L.; Smith, Seth A.; Landman, Bennett A.

    2015-03-01

    Optic neuritis is a sudden inflammation of the optic nerve (ON) and is marked by pain on eye movement, and visual symptoms such as a decrease in visual acuity, color vision, contrast and visual field defects. The ON is closely linked with multiple sclerosis (MS) and patients have a 50% chance of developing MS within 15 years. Recent advances in multi-atlas segmentation methods have omitted volumetric assessment. In the past, measuring the size of the ON has been done by hand. We utilize a new method of automatically segmenting the ON to measure the radii of both the ON and surrounding cerebrospinal fluid (CSF) sheath to develop a normative distribution of healthy young adults. We examine this distribution for any trends and find that ON and CSF sheath radii do not vary between 20-35 years of age and between sexes. We evaluate how six patients suffering from optic neuropathy compare to this distribution of controls. We find that of these six patients, five of them qualitatively differ from the normative distribution which suggests this technique could be used in the future to distinguish between optic neuritis patients and healthy controls

  11. Optic Nerve Sheath Diameter: Translating a Terrestrial Focused Technique Into a Clinical Monitoring Tool for Space Flight

    NASA Technical Reports Server (NTRS)

    Mason, Sara S.; Foy, Millennia; Sargsyan, Ashot; Garcia, Kathleen; Wear, Mary L.; Bedi, Deepak; Ernst, Randy; Van Baalen, Mary

    2014-01-01

    Emergency medicine physicians recently adopted the use of ultrasonography to quickly measure optic nerve sheath diameter (ONSD) as concomitant with increased intracranial pressure. NASA Space and Clinical Operations Division has been using ground and on-orbit ultrasound capabilities since 2009 to consider this anatomical measure as a proxy for intracranial pressure in the microgravity environment. In the terrestrial emergency room population, an ONSD greater than 0.59 cm is considered highly predictive of elevated intracranial pressure. However, this cut-off limit is not applicable to the spaceflight setting since over 50% of US Operating Segment (USOS) astronauts have an ONSD greater than 0.60 cm even before missions. Crew Surgeon clinical decision-making is complicated by the fact that many astronauts have history of previous spaceflights. Data will be presented characterizing the distribution of baseline ONSD in the astronaut corps, longitudinal trends in-flight, and the predictive power of this measure related to increased intracranial pressure outcomes.

  12. Intracranial pressure-induced optic nerve sheath response as a predictive biomarker for optic disc edema in astronauts.

    PubMed

    Wostyn, Peter; De Deyn, Peter Paul

    2017-09-04

    A significant proportion of the astronauts who spend extended periods in microgravity develop ophthalmic abnormalities. Understanding this syndrome, called visual impairment and intracranial pressure (VIIP), has become a high priority for National Aeronautics and Space Administration, especially in view of future long-duration missions (e.g., Mars missions). Moreover, to ensure selection of astronaut candidates who will be able to complete long-duration missions with low risk of the VIIP syndrome, it is imperative to identify biomarkers for VIIP risk prediction. Here, we hypothesize that the optic nerve sheath response to alterations in intracranial pressure may be a potential predictive biomarker for optic disc edema in astronauts. If confirmed, this biomarker could be used for preflight identification of astronauts at risk for developing VIIP-associated optic disc edema.

  13. Primary hepatic malignant peripheral nerve sheath tumor successfully treated with combination therapy: a case report and literature review

    PubMed Central

    Jung, Hae Il; Lee, Hyoung Uk; Ahn, Tae Sung; Lee, Jong Eun; Lee, Hyun Yong; Cho, Hyon Doek; Lee, Sang Cheol

    2016-01-01

    Primary malignant peripheral nerve sheath tumor (MPNST) in a young female patient, not associated with neurofibromatosis type-I is extremely rare in the liver. A 33-year-old female was admitted with a right flank pain for a weak. The CT scan showed 12.5-cm-sized mass located at the right hepatic lobe. At laparotomy, about 20.0-cm-sized mass was on the right hepatic lobe with attachment to right diaphragmatic pleura. Right hepatic lobe and adherent part of diaphragmatic pleura were resected. On histology and immunohistochemistry, it was diagnosed MPNST. Adjuvant radiotherapy for the right diaphragmatic pleura and adjuvant chemotherapy with adriamycin, ifosfamide and cisplatin were sequentially performed. The prognosis of MPNST is generally poor and it is associated with a highly aggressive course of recurrence, metastases, and death. Our case is probably a first report about combination therapy. PMID:27904856

  14. [Malignant peripheric nerve sheath tumor of the orbit: first description of orbital location in a patient with NF1].

    PubMed

    Romero-Rojas, A E; Díaz-Pérez, J A; Lozano-Castillo, A

    2010-02-01

    The malignant peripheric nerve sheath tumor (MPNST), is a malignant neoplastic lesion originated in Schwann cells of the lining sheath of peripheral nerves. This neoplasia may appear with benign or malignant heterologous components, with divergent differentiation, as the glandular one. To describe for the first time in the literature, a case of a glandular MPNST, located at the orbit and to revise the literature on this tumoral lesion. Nine year old male, with a base diagnosis of NF1, who had exophthalmos, retro-ocular pain, headache, facial asymmetry and descent of the right eyeball, that started 1 year earlier. This patient showed in the Computed Tomography an Magnetic Resonance, a well delimited, lobulated, solid mass at the eyeball, which extended to the fontal and temporal brain parenchyma. A right Fronto-temporal craniotomy was made with fronto -orbital- zygomatic resection of the tumoral lesion. Later, a dural plasty and reconstruction with titanium mesh was made at the skull base. At present, the patient is asymptomatic after 4 months of follow up. A malignant biphasic neoplastic lesion was observed, reactive in the mesenchymal elements S100, PGP 9.5, neurofilaments and vimentin. The glandular component was positive for AE1/AE3, EMA, CEA and focally for CD57. There was also reactivity to cromogranin, synaptophysin, serotonin and somatostatin. The diagnosis of Glandular MPNST was made. For the first time in the literature a case of Glandular MPNST located at the orbit, which occurred in child with NF1, is described. This extremely uncommon neoplasia must be taken into account, in the study of biphasic malignant lesions, as its diagnosis is of great importance because of the bad prognosis of the affected patients.

  15. Narrowing of Meckel's cave and cavernous sinus and enlargement of the optic nerve sheath in Pseudotumor Cerebri.

    PubMed

    Degnan, Andrew Joseph; Levy, Lucien M

    2011-01-01

    Pseudotumor cerebri (PTC) is a clinical entity of uncertain etiology associated with several subtle findings on magnetic resonance imaging (MRI) including posterior flattening of the globes, enlargement of the optic nerve sheath (ONS), empty sella sign. We aimed to characterize the incidence of and significance of 2 novel MRI findings: narrowing of Meckel's cave and of cavernous sinus. Forty-six patients with a condition diagnosed as PTC based on clinical history were retrospectively reviewed, and their MRI studies were assessed for previously reported imaging findings associated with PTC. The maximal diameters of the cavernous sinuses, Meckel's caves, and ONSs were measured along with those of age-matched controls on axial T2-weighted images. The Meckel's caves and cavernous sinuses are significantly (P < 0.01) narrowed in patients (mean diameters: 0.41 and 0.25 cm) versus controls (0.54 and 0.36 cm), respectively. The ONS was enlarged in patients with a mean diameter of 0.65 cm versus 0.54 cm (P < 0.01). Meckel's cave narrowing and ONS enlargement seem to be better indicators of PTC than cavernous sinus narrowing, with sensitivities of 78.3% and 86.9% and specificities of 84.8% and 76.1% versus 60.9% and 76.1%, respectively. This finding of narrowed Meckel's caves in PTC may be clinically useful as a novel imaging finding seen on routine MRI studies. Optic nerve sheath enlargement is also confirmed as an important finding in PTC.

  16. Electrophoresis of polar fluorescent tracers through the nerve sheath labels neuronal populations for anatomical and functional imaging

    PubMed Central

    Isaacson, Matthew D.; Hedwig, Berthold

    2017-01-01

    The delivery of tracers into populations of neurons is essential to visualize their anatomy and analyze their function. In some model systems genetically-targeted expression of fluorescent proteins is the method of choice; however, these genetic tools are not available for most organisms and alternative labeling methods are very limited. Here we describe a new method for neuronal labelling by electrophoretic dye delivery from a suction electrode directly through the neuronal sheath of nerves and ganglia in insects. Polar tracer molecules were delivered into the locust auditory nerve without destroying its function, simultaneously staining peripheral sensory structures and central axonal projections. Local neuron populations could be labelled directly through the surface of the brain, and in-vivo optical imaging of sound-evoked activity was achieved through the electrophoretic delivery of calcium indicators. The method provides a new tool for studying how stimuli are processed in peripheral and central sensory pathways and is a significant advance for the study of nervous systems in non-model organisms. PMID:28084413

  17. Cytohistologic correlations of 24 malignant peripheral nerve sheath tumor (MPNST) in 17 patients: the Institut Curie experience.

    PubMed

    Klijanienko, Jerzy; Caillaud, Jean-Michel; Lagacé, Réal; Vielh, Philippe

    2002-08-01

    Cytomorphological patterns of malignant peripheral nerve sheath tumor (MPNST) are insufficiently documented in the literature. Cytological and histological specimens in 24 tumors in 17 patients were correlated. The review of the original cytology reports showed that four (16.6%) tumors were correctly diagnosed, eight (33.3%) were diagnosed as sarcoma not otherwise specified, four (16.7%) as fibrosarcoma, three (12.5%) as synovial sarcoma, three (12.5%) as leiomyosarcoma, and one (4.2%) case each as malignant fibrous histiocytoma and rhabdomyosarcoma. At the review tumors were histologically reclassified as well-differentiated MPNST in 11 (45.9%) cases, anaplastic MPNST in 11 (45.9%) cases, and epithelioid MPNST and malignant Triton tumor in one (4.2%) case each. Cytologically, well-differentiated MPNST were composed of polymorphous oval to round cells, small spindle-shaped cells with wavy and comma-like naked nuclei, and a fibrillary, delicate stroma. Anaplastic MPNST, moreover, were composed of anaplastic giant and polymorphous cells. The malignant Triton tumor was composed of oval to round rhabdomyoblastic cells with eccentric nuclei and the epithelioid MPNST of polymorphous and round, epithelial-like cells. The cytological diagnosis of MPNST may be difficult, especially in anaplastic tumors. The correlation between the cytological features and the clinical information--origin of the tumor from a nerve trunk, a preexisting neurofibroma, patients with known history of neurofibromatosis 1--could be indicative of an MPNST diagnosis.

  18. Association of tumor location, extent of resection, and neurofibromatosis status with clinical outcomes for 221 spinal nerve sheath tumors.

    PubMed

    Safaee, Michael; Parsa, Andrew T; Barbaro, Nicholas M; Chou, Dean; Mummaneni, Praveen V; Weinstein, Philip R; Tihan, Tarik; Ames, Christopher P

    2015-08-01

    OBJECT Intradural extramedullary spine tumors represent two-thirds of all primary spine neoplasms. Approximately half of these are peripheral nerve sheath tumors, mainly neurofibromas and schwannomas. Given the rarity of this disease and, thus, the limited analyses of clinical outcomes, the authors examined the association of tumor location, extent of resection, and neurofibromatosis (NF) status with clinical outcomes. METHODS Patients were identified through a search of the University of California, San Francisco, neuropathology database and a separate review of current procedural terminology codes. Data recorded included patient age, patient sex, clinical presentation, presence of NF, tumor type, tumor location, extent of resection (gross-total resection [GTR] or subtotal resection [STR]), and clinical follow-up. RESULTS Of 221 tumors in 199 patients (mean age 45 years), 53 were neurofibromas, 163 were schwannomas, and 5 were malignant peripheral nerve sheath tumors. The most common presenting symptom was spinal pain (76%), followed by weakness (36%) and sensory abnormalities (34%). Mean symptom duration was 16 months. In terms of spinal location, neurofibromas were more common in the cervical spine (74% vs 27%, p < 0.001), and schwannomas were more common in the thoracic and lumbosacral spine (73% vs 26%, p < 0.001). Rates of GTR were lower for neurofibromas than schwannomas (51% vs 83%, p < 0.001), regardless of location. Rates of GTR were lower for cervical (54%) than thoracic (90%) and lumbosacral (86%) lesions (p < 0.001). NF was associated with lower rates of GTR among all tumors (43% vs 86%, p < 0.001). The mean follow-up time was 32 months. Recurrence/progression was more common for neurofibromas than schwannomas (17% vs 7%, p = 0.03), although the mean time to recurrence/progression did not differ according to tumor type (45 vs 53 months, p = 0.63). As expected, GTR was associated with lower recurrence rates (4% vs 22%, p < 0.001). According to

  19. Optic nerve sheath diameter measurement: a means of detecting raised ICP in adult traumatic and non-traumatic neurosurgical patients.

    PubMed

    Raffiz, Mohd; Abdullah, Jafri M

    2017-01-01

    Bedside ultrasound measurement of optic nerve sheath diameter (ONSD) is emerging as a non-invasive technique to evaluate and predict raised intracranial pressure (ICP). It has been shown in previous literature that ONSD measurement has good correlation with surrogate findings of raised ICP such as clinical and radiological findings suggestive of raised ICP. The objective of the study is to find a correlation between sonographic measurements of ONSD value with ICP value measured via the gold standard invasive intracranial ICP catheter, and to find the cut-off value of ONSD measurement in predicting raised ICP, along with its sensitivity and specificity value. A prospective observational study was performed using convenience sample of 41 adult neurosurgical patients treated in neurosurgical intensive care unit with invasive intracranial pressure monitoring placed in-situ as part of their clinical care. Portable SonoSite ultrasound machine with 7 MHz linear probe were used to measure optic nerve sheath diameter using the standard technique. Simultaneous ICP readings were obtained directly from the invasive monitoring. Seventy-five measurements were performed on 41 patients. The non-parametric Spearman correlation test revealed a significant correlation at the 0.01 level between the ICP and ONSD value, with correlation coefficient of 0.820. The receiver operating characteristic curve generated an area under the curve with the value of 0.964, and with standard error of 0.22. From the receiver operating characteristic curve, we found that the ONSD value of 5.205 mm is 95.8% sensitive and 80.4% specific in detecting raised ICP. ONSD value of 5.205 is sensitive and specific in detecting raised ICP. Bedside ultrasound measurement of ONSD is readily learned, and is reproducible and reliable in predicting raised ICP. This non-invasive technique can be a useful adjunct to the current invasive intracranial catheter monitoring, and has wide potential clinical applications in

  20. Influence of Breaching the Connective Sheaths of the Donor Nerve on Its Myelinated Sensory Axons and on Their Sprouting into the End-to-Side Coapted Nerve in the Rat

    PubMed Central

    Žele, Tilen; Tomšič, Martin; Sketelj, Janez; Bajrović, Fajko F.

    2012-01-01

    Abstract The influence of breaching the connective sheaths of the donor sural nerve on axonal sprouting into the end-to-side coapted peroneal nerve was examined in the rat. In parallel, the effect of these procedures on the donor nerve was assessed. The sheaths of the donor nerve at the coaptation site were either left completely intact (group A) or they were breached by epineurial sutures (group B), an epineurial window (group C), or a perineurial window (group D). In group A, the compound action potential (CAP) of sensory axons was detected in ∼10% and 40% of the recipient nerves at 4 and 8 weeks, respectively, which was significantly less frequently than in group D at both recovery periods. In addition, the number of myelinated axons in the recipient nerve was significantly larger in group D than in other groups at 4 weeks. At 8 weeks, the number of axons in group A was only ∼15% of the axon numbers in other groups (p<0.05). Focal subepineurial degenerative changes in the donor nerves were only seen after 4 weeks, but not later. The average CAP area and the total number of myelinated axons in the donor nerves were not different among the experimental groups. In conclusion, myelinated sensory axons are able to penetrate the epiperineurium of donor nerves after end-to-side nerve coaption; however, their ingrowth into recipient nerves is significantly enhanced by breaching the epiperineurial sheets at the coaptation site. Breaching does not cause permanent injury to the donor nerve. PMID:22873667

  1. Comprehensive establishment and characterization of orthoxenograft mouse models of malignant peripheral nerve sheath tumors for personalized medicine.

    PubMed

    Castellsagué, Joan; Gel, Bernat; Fernández-Rodríguez, Juana; Llatjós, Roger; Blanco, Ignacio; Benavente, Yolanda; Pérez-Sidelnikova, Diana; García-Del Muro, Javier; Viñals, Joan Maria; Vidal, August; Valdés-Mas, Rafael; Terribas, Ernest; López-Doriga, Adriana; Pujana, Miguel Angel; Capellá, Gabriel; Puente, Xose S; Serra, Eduard; Villanueva, Alberto; Lázaro, Conxi

    2015-05-01

    Malignant peripheral nerve sheath tumors (MPNSTs) are soft-tissue sarcomas that can arise either sporadically or in association with neurofibromatosis type 1 (NF1). These aggressive malignancies confer poor survival, with no effective therapy available. We present the generation and characterization of five distinct MPNST orthoxenograft models for preclinical testing and personalized medicine. Four of the models are patient-derived tumor xenografts (PDTX), two independent MPNSTs from the same NF1 patient and two from different sporadic patients. The fifth model is an orthoxenograft derived from an NF1-related MPNST cell line. All MPNST orthoxenografts were generated by tumor implantation, or cell line injection, next to the sciatic nerve of nude mice, and were perpetuated by 7-10 mouse-to-mouse passages. The models reliably recapitulate the histopathological properties of their parental primary tumors. They also mimic distal dissemination properties in mice. Human stroma was rapidly lost after MPNST engraftment and replaced by murine stroma, which facilitated genomic tumor characterization. Compatible with an origin in a catastrophic event and subsequent genome stabilization, MPNST contained highly altered genomes that remained remarkably stable in orthoxenograft establishment and along passages. Mutational frequency and type of somatic point mutations were highly variable among the different MPNSTs modeled, but very consistent when comparing primary tumors with matched orthoxenografts generated. Unsupervised cluster analysis and principal component analysis (PCA) using an MPNST expression signature of ~1,000 genes grouped together all primary tumor-orthoxenograft pairs. Our work points to differences in the engraftment process of primary tumors compared with the engraftment of established cell lines. Following standardization and extensive characterization and validation, the orthoxenograft models were used for initial preclinical drug testing. Sorafenib (a BRAF

  2. Clinical significance of postoperative changes in redundant nerve roots after decompressive laminectomy for lumbar spinal canal stenosis.

    PubMed

    Yokoyama, Kunio; Kawanishi, Masahiro; Yamada, Makoto; Tanaka, Hidekazu; Ito, Yutaka; Hirano, Masashi; Kawabata, Shinji; Kuroiwa, Toshihiko

    2014-12-01

    The postoperative time course of redundant nerve roots (RNRs) in patients with lumbar spinal canal stenosis (LSCS) is currently unknown. The purpose of this study is to investigate the relationship between postoperative morphologic changes in detected RNRs and the clinical outcome of patients with LSCS. A total of 33 symptomatic patients with LSCS who demonstrated RNRs on magnetic resonance imaging (MRI) were treated with decompressive laminectomy alone. On the basis of the MRI scans obtained 7 days after surgery, patients were stratified into two groups: group 1 included patients with resolution of RNRs and group 2 included patients with persistent RNRs. Comparative parameters were examined between the two groups of patients. We found that 24 of the 33 patients showed resolution of RNRs and 9 showed persistent RNRs. Although there was no difference in the Japanese Orthopedic Association score between the two groups before treatment, group 1 showed a greater recovery of Japanese Orthopedic Association score 1 month postoperatively. MRI demonstrated that the cross-sectional area of the preoperative dural sac at the stenotic lesion was smaller in group 2 than in group 1; however, there was no difference in cross-sectional area of the postoperative dural sac between the two groups. Within 12 months, there was no evidence of RNRs in six of the nine cases in group 2. Although most patients with LSCS show postoperative resolution of RNRs detected on MRI, some show persistent RNRs postoperatively. The functional outcome of these patients remains poor even if sufficient expansion of the dural sac is achieved postoperatively. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. Illustration of Cost Saving Implications of Lower Extremity Nerve Decompression to Prevent Recurrence of Diabetic Foot Ulceration

    PubMed Central

    Rankin, Timothy M.; Miller, John D.; Gruessner, Angelika C.; Nickerson, D. Scott

    2015-01-01

    The US diabetic foot ulcer (DFU) incidence is 3-4% of 22.3 million diagnosed diabetes cases plus 6.3 million undiagnosed, 858 000 cases total. Risk of recurrence after healing is 30% annually. Lower extremity multiple nerve decompression (ND) surgery reduces neuropathic DFU (nDFU) recurrence risk by >80%. Cost effectiveness of hypothetical ND implementation to minimize nDFU recurrence is compared to the current $6.171 billion annual nDFU expense. A literature review identified best estimates of annual incidence, recurrence risk, medical management expense, and noneconomic costs for DFU. Illustrative cost/benefit calculations were performed assuming widespread application of bilateral ND after wound healing to the nDFU problem, using Center for Medicare Services mean expense data of $1143/case for unilateral lower extremity ND. Calculations use conservative, evidence-based cost figures, which are contemporary (2012) or adjusted for inflation. Widespread adoption of ND after nDFU healing could reduce annual DFU occurrences by at least 21% in the third year and 24% by year 5, representing calculated cost savings of $1.296 billion (year 3) to $1.481 billion (year 5). This scenario proffers significant expense reduction and societal benefit, and represents a minimum 1.9× return on the investment cost for surgical treatment. Further large cost savings would require reductions in initial DFU incidence, which ND might achieve by selective application to advanced diabetic sensorimotor polyneuropathy (DSPN). By minimizing the contribution of recurrences to yearly nDFU incidence, ND has potential to reduce by nearly $1 billion the annual cost of DFU treatment in the United States. PMID:26055081

  4. Combinatorial therapeutic targeting of BMP2 and MEK-ERK pathways in NF1-associated malignant peripheral nerve sheath tumors

    PubMed Central

    Ahsan, Sidra; Ge, Yubin; Tainsky, Michael A.

    2016-01-01

    The clinical management of malignant peripheral nerve sheath tumors (MPNSTs) is challenging not only due to its aggressive and invasive nature, but also limited therapeutic options. Using gene expression profiling, our lab identified BMP2-SMAD1/5/8 pathway as a potential therapeutic target for treating MPNSTs. In this study, we explored the therapeutic impact of targeting BMP2-SMAD1/5/8 pathway in conjunction with RAS-MEK-ERK signaling, which is constitutively activated in MPNSTs. Our results indicated that single agent treatment with LDN-193189, a BMP2 Type I receptor inhibitor, did not affect the growth and survival of MPNST cells at biochemically relevant inhibitory concentrations. However, addition of a MEK1/2 inhibitor, selumetinib, to LDN-193189-treated cells resulted in significant inhibition of cell growth and induction of cell death. LDN-193189 at biochemically effective concentrations significantly inhibited motility and invasiveness of MPNST cells, and these effects were enhanced by the addition of selumetinib. Overall, our results advocate for a combinatorial therapeutic approach for MPNSTs that not only targets the growth and survival via inhibition of MEK1/2, but also its malignant spread by suppressing the activation of BMP2-SMAD1/5/8 pathway. Importantly, these studies were conducted in low-passage patient-derived MPNST cells, allowing for an investigation of the effects of the proposed drug treatments in a biologically-relevant context. PMID:27494873

  5. Standard-Fractionated Radiotherapy for Optic Nerve Sheath Meningioma: Visual Outcome Is Predicted by Mean Eye Dose

    SciTech Connect

    Abouaf, Lucie; Girard, Nicolas; Lefort, Thibaud; D'hombres, Anne; Tilikete, Caroline; Vighetto, Alain; Mornex, Francoise

    2012-03-01

    Purpose: Radiotherapy has shown its efficacy in controlling optic nerve sheath meningiomas (ONSM) tumor growth while allowing visual acuity to improve or stabilize. However, radiation-induced toxicity may ultimately jeopardize the functional benefit. The purpose of this study was to identify predictive factors of poor visual outcome in patients receiving radiotherapy for ONSM. Methods and Materials: We conducted an extensive analysis of 10 patients with ONSM with regard to clinical, radiologic, and dosimetric aspects. All patients were treated with conformal radiotherapy and subsequently underwent biannual neuroophthalmologic and imaging assessments. Pretreatment and posttreatment values of visual acuity and visual field were compared with Wilcoxon's signed rank test. Results: Visual acuity values significantly improved after radiotherapy. After a median follow-up time of 51 months, 6 patients had improved visual acuity, 4 patients had improved visual field, 1 patient was in stable condition, and 1 patient had deteriorated visual acuity and visual field. Tumor control rate was 100% at magnetic resonance imaging assessment. Visual acuity deterioration after radiotherapy was related to radiation-induced retinopathy in 2 patients and radiation-induced mature cataract in 1 patient. Study of radiotherapy parameters showed that the mean eye dose was significantly higher in those 3 patients who had deteriorated vision. Conclusions: Our study confirms that radiotherapy is efficient in treating ONSM. Long-term visual outcome may be compromised by radiation-induced side effects. Mean eye dose has to be considered as a limiting constraint in treatment planning.

  6. Multicentric fibromyxoid peripheral nerve sheath tumor (multicentric schwannoma) in a dromedary camel (Camelus dromedarius): morphopathological, immunohistochemical, and electron microscopic studies.

    PubMed

    Khodakaram-Tafti, A; Khordadmehr, M

    2011-11-01

    During postslaughter inspection of a 4-year-old male dromedary camel (Camelus dromedarius), numerous small nodules to large masses up to 4 cm in diameter were found on the serosal surfaces of forestomachs, large intestines, mesentery, liver, and spleen. Grossly, the masses were discrete, round, smooth, and white to gray that bulged from the serosal layer. Cut surfaces of the masses were discrete, round, white, and relatively homogeneous without any necrotic foci. Histopathologically, the masses were encapsulated and composed of a mixture of round and spindle-shaped cells in loose whorls of neoplastic cells with small elongated hyperchromatic wavy nuclei and a small amount of pale eosinophilic, poorly defined cytoplasm. Masson's trichrome staining showed mild amounts of collagen fibers forming an irregular, loose stroma. In immunohistochemistry, immunoreactivity for the Schwann cell marker (S100) was diffusely positive in the neoplastic cells. The immunoreactivity for CK, c-kit, and CD34 were negative. Ultrastructural examination confirmed the tumor was entirely formed of neoplastic Schwann cells. On the basis of the histopathological, immunohistochemical, and ultrastructural findings, the tumors were diagnosed as multicentric fibromyxoid peripheral nerve sheath tumor (multicentric schwannoma). This tumor has not been previously recorded in camel worldwide.

  7. Photothermal therapy improves the efficacy of a MEK inhibitor in neurofibromatosis type 1-associated malignant peripheral nerve sheath tumors

    PubMed Central

    Sweeney, Elizabeth E.; Burga, Rachel A.; Li, Chaoyang; Zhu, Yuan; Fernandes, Rohan

    2016-01-01

    Malignant peripheral nerve sheath tumors (MPNSTs) are aggressive tumors with low survival rates and the leading cause of death in neurofibromatosis type 1 (NF1) patients under 40 years old. Surgical resection is the standard of care for MPNSTs, but is often incomplete and can generate loss of function, necessitating the development of novel treatment methods for this patient population. Here, we describe a novel combination therapy comprising MEK inhibition and nanoparticle-based photothermal therapy (PTT) for MPNSTs. MEK inhibitors block activity driven by Ras, an oncogene constitutively activated in NF1-associated MPNSTs, while PTT serves as a minimally invasive method to ablate cancer cells. Our rationale for combining these seemingly disparate techniques for MPNSTs is based on several reports demonstrating the efficacy of systemic chemotherapy with local PTT. We combine the MEK inhibitor, PD-0325901 (PD901), with Prussian blue nanoparticles (PBNPs) as PTT agents, to block MEK activity and simultaneously ablate MPNSTs. Our data demonstrate the synergistic effect of combining PD901 with PBNP-based PTT, which converge through the Ras pathway to generate apoptosis, necrosis, and decreased proliferation, thereby mitigating tumor growth and increasing survival of MPNST-bearing animals. Our results suggest the potential of this novel local-systemic combination “nanochemotherapy” for treating patients with MPNSTs. PMID:27833160

  8. Chemotherapy for the treatment of malignant peripheral nerve sheath tumors in neurofibromatosis 1: a 10-year institutional review

    PubMed Central

    2013-01-01

    Background Neurofibromatosis 1 (NF1) is the most common autosomal dominant disorder, with an incidence of 1 in 2,500-3,300 live births. NF1 is associated with significant morbidity and mortality because of complications, especially malignant peripheral nerve sheath tumors (MPNSTs), which mainly develop during adulthood. We evaluated our experience with management of NF1 with MPNSTs by standard chemotherapy with anthracycline and/or ifosfamide in terms of time to treatment failure and overall survival. Methods We performed a retrospective review of consecutive patients with NF1 and a diagnosis of MPNSTs between 1993 and 2003 in our referral center for NF1. Prognostic factors were evaluated by univariate analysis. Results We evaluated data for 21 patients with grade 1 (n=1), grade 2 (n=8) and grade 3 (n=12) MPNST; 16 presented localized disease and underwent surgery: margins for 6 were tumor-free (including 3 patients with amputation), 2 showed microscopic residual disease and 8 showed macroscopic residual disease. All patients received chemotherapy and 9 radiotherapy. Median time to treatment failure and overall survival were 7.8 and 17 months, respectively. Two patients were still alive at 138 and 167 months. We found no significant relationship between type of chemotherapy and time to treatment failure or overall survival. Conclusions MPNSTs are highly aggressive in NF1. Conventional chemotherapy does not seem to reduce mortality, and its role must be questioned. Recent advances in the molecular biology of MPNSTs may provide new prognostic factors and targeted therapies. PMID:23972085

  9. Combinatorial therapy with tamoxifen and trifluoperazine effectively inhibits malignant peripheral nerve sheath tumor growth by targeting complementary signaling cascades.

    PubMed

    Brosius, Stephanie N; Turk, Amy N; Byer, Stephanie J; Longo, Jody Fromm; Kappes, John C; Roth, Kevin A; Carroll, Steven L

    2014-11-01

    Chemotherapeutic agents effective against malignant peripheral nerve sheath tumors (MPNSTs) are urgently needed. We recently found that tamoxifen potently impedes xenograft growth. In vitro, tamoxifen inhibits MPNST proliferation and survival in an estrogen receptor-independent manner; these effects are phenocopied by the calmodulin inhibitor trifluoperazine. The present study was performed to establish the mechanism of action of tamoxifen in vivo and optimize its therapeutic effectiveness. To determine if tamoxifen has estrogen receptor-dependent effects in vivo, we grafted MPNST cells in castrated and ovariectomized mice; xenograft growth was unaffected by reductions in sex hormones. To establish whether tamoxifen and trifluoperazine additively or synergistically impede MPNST growth, mice xenografted with neurofibromatosis type 1-associated or sporadic MPNST cells were treated with tamoxifen, trifluoperazine, or both drugs for 30 days. Both monotherapies inhibited graft growth by 50%, whereas combinatorial treatment maximally reduced graft mass by 90% and enhanced decreases in proliferation and survival. Kinomic analyses showed that tamoxifen and trifluoperazine have both shared and distinct targets in MPNSTs. In addition, trifluoperazine prevented tamoxifen-induced increases in serum/glucocorticoid regulated kinase 1, a protein linked to tamoxifen resistance. These findings suggest that combinatorial therapy with tamoxifen and trifluoperazine is effective against MPNSTs because these agents target complementary pathways that are essential for MPNST pathogenesis.

  10. Malignant peripheral nerve sheath tumor (MPNST) in the spine: a retrospective analysis of clinical and molecular prognostic factors.

    PubMed

    Wang, Ting; Yin, Huabin; Han, Shuai; Yang, Xinhai; Wang, Jing; Huang, Quan; Yan, Wangjun; Zhou, Wang; Xiao, Jianru

    2015-04-01

    Spinal malignant peripheral nerve sheath tumors (MPNSTs) are relatively rare. There is little information published in the literature regarding this subject. The aim of this retrospective study was to evaluate factors that may affect the outcomes of patients with spinal MPNSTs by reviewing 43 patients with spinal MPNST who were treated in our hospital between 2001 and 2012. Univariate and multivariate analyses were performed to identify prognostic variables relative to patient and tumor characteristics, treatment modality and molecules. All 43 MPNST patients (25 men and 18 women; median age 49 years) underwent surgical resection, of whom 15 patients also underwent postoperative radiotherapy. Local recurrence was found in 21 (48.8 %) patients. Twenty-two (51.2 %) patients died during the follow-up periods with a median survival time of 49 months. The 5-year recurrence and survival rate was 53 and 44 % respectively. The statistical analyses suggested that high-grade malignancy and osteolytic destruction were closely associated with recurrence and death. A total of 38 cases accepted postoperative immunohistochemisty examine. S-100 was identified as an independent factor related to both recurrence and survival, adjusting for clinical factors. In conclusion, we confirmed that malignant grade and osteolytic destruction were the two independent factors for both recurrence and survival, while patients with S-100 protein negative had a higher recurrence rate and a lower survival rate.

  11. [Case of abdominal wall malignant peripheral nerve sheath tumor which is difficult to distinguish from a urachal disease].

    PubMed

    Tatenuma, Tomoyuki; Sakata, Ryoko; Sugiura, Shinpei; Tajiri, Takehiro; Gondo, Toshikazu; Kitami, Kazuo

    2013-09-01

    Malignant peripheral nerve sheath tumors (MPNST) are highly malignant soft tissue sarcomas. It is very rare for MPNST to arise in the abdominal wall. We report a case of abdominal wall MPNST that was difficult to distinguish from a urachal disease. A 72-year-old woman found a mass of the umbilicus in October 2011. She visited a digestive surgery department in November because it gradually enlarged. Diagnostic imaging suggested a urachal tumor. She was then referred to our clinic. Contrast enhanced CT showed that the 5-cm cystic tumor extended from the umbilicus to abdominal wall. The tumor showed low uptake value in PET-CT. We diagnosed her with a urachal cyst, but could not deny urachal carcinoma. Therefore, we performed surgical resection in January 2012. The pathological diagnosis was MPNST. She has not experienced recurrence for 9 months. MPNST mostly occur in the retroperitoneum close to the spine, extremities, head, and neck. It is very rare for them to occur in the abdominal wall. This is the sixth case including overseas reports. In addition, this is the first case in which it was difficult to distinguish from a urachal disease.

  12. Pediatric and adult malignant peripheral nerve sheath tumors: an analysis of data from the surveillance, epidemiology, and end results program.

    PubMed

    Amirian, E Susan; Goodman, J Clay; New, Pamela; Scheurer, Michael E

    2014-02-01

    Malignant peripheral nerve sheath tumors (MPNSTs) are rare soft tissue sarcomas that arise predominantly from Schwann cells. Despite the fact that MPNSTs have high local recurrence rates and are generally associated with poor prognosis, little is known about prognostic factors or effective clinical management for this tumor type. The purpose of this study was to describe the distributions of patient and tumor characteristics and to identify predictors of cause-specific survival among MPNST cases reported to SEER between 1973 and 2008. Patient and tumor characteristics were compared between pediatric and adult MPNST cases. Cox regression and tree-based survival analysis were used to examine factors associated with MPNST-related mortality separately among adults and children. A total of 1,315 MPNST cases were isolated from the 1973-2008 SEER dataset. Among pediatric cases, sex, race, and radiation therapy predicted MPNST survival, whereas among adults, tumor site, tumor grade, number of primary tumors, and tumor size were significant predictors. As tumor size at diagnosis/resection may be the only somewhat "modifiable" prognostic factor, future studies should aim to identify biological and social attributes associated with tumor size at diagnosis, separately among individuals with and without NF-1, in order to help identify earlier opportunities for clinical intervention.

  13. Involvement of PACAP/ADNP signaling in the resistance to cell death in malignant peripheral nerve sheath tumor (MPNST) cells.

    PubMed

    Castorina, Alessandro; Giunta, Salvatore; Scuderi, Soraya; D'Agata, Velia

    2012-11-01

    Malignant peripheral nerve sheath tumors (MPNSTs) are sarcomas able to grow under conditions of metabolic stress caused by insufficient nutrients or oxygen. Both pituitary adenylate cyclase-activating polypeptide (PACAP) and activity-dependent neuroprotective protein (ADNP) have glioprotective potential. However, whether PACAP/ADNP signaling is involved in the resistance to cell death in MPNST cells remains to be clarified. Here, we investigated the involvement of this signaling system in the survival response of MPNST cells against hydrogen peroxide (H(2)O(2))-evoked death both in the presence of normal serum (NS) and in serum-starved (SS) cells. Results showed that ADNP levels increased time-dependently (6-48 h) in SS cells. Treatment with PACAP38 (10(-9) to 10(-5) M) dose-dependently increased ADNP levels in NS but not in SS cells. PAC(1)/VPAC receptor antagonists completely suppressed PACAP-stimulated ADNP increase and partially reduced ADNP expression in SS cells. NS-cultured cells exposed to H(2)O(2) showed significantly reduced cell viability (~50 %), increased p53 and caspase-3, and DNA fragmentation, without affecting ADNP expression. Serum starvation significantly reduced H(2)O(2)-induced detrimental effects in MPNST cells, which were not further ameliorated by PACAP38. Altogether, these finding provide evidence for the involvement of an endogenous PACAP-mediated ADNP signaling system that increases MPNST cell resistance to H(2)O(2)-induced death upon serum starvation.

  14. Preclinical evaluation of the combination of mTOR and proteasome inhibitors with radiotherapy in malignant peripheral nerve sheath tumors.

    PubMed

    Yamashita, A S; Baia, G S; Ho, J S Y; Velarde, E; Wong, J; Gallia, G L; Belzberg, A J; Kimura, E T; Riggins, G J

    2014-05-01

    About one half of malignant peripheral nerve sheath tumors (MPNST) have Neurofibromin 1 (NF1) mutations. NF1 is a tumor suppressor gene essential for negative regulation of RAS signaling. Survival for MPNST patients is poor and we sought to identify an effective combination therapy. Starting with the mTOR inhibitors rapamycin and everolimus, we screened for synergy in 542 FDA approved compounds using MPNST cells with a native NF1 loss in both alleles. We further analyzed the cell cycle and signal transduction. In vivo growth effects of the drug combination with local radiation therapy (RT) were assessed in MPNST xenografts. The synergistic combination of mTOR inhibitors with bortezomib yielded a reduction in MPNST cell proliferation. The combination of mTOR inhibitors and bortezomib also enhanced the anti-proliferative effect of radiation in vitro. In vivo, the combination of mTOR inhibitor (everolimus) and bortezomib with RT decreased tumor growth and proliferation, and augmented apoptosis. The combination of approved mTOR and proteasome inhibitors with radiation showed a significant reduction of tumor growth in an animal model and should be investigated and optimized further for MPNST therapy.

  15. Malignant Triton Tumor (Malignant Peripheral Nerve Sheath Tumor With Rhabdomyoblastic Differentiation) Occurring in a Vascularized Free Flap Reconstruction Graft.

    PubMed

    Ram, Roopa; Gardner, Jerad; Alapati, Sindhura; Jambhekar, Kedar; Pandey, Tarun; Montgomery, Corey; Nicholas, Richard

    2017-08-01

    Malignant peripheral nerve sheath tumor (MPNST) is a rare form of sarcoma arising from Schwann cells or pluripotent cells of the neural crest. Malignant triton tumor (MTT) is a subtype of MPNST with a component of malignant rhabdomyoblasts in addition to malignant Schwann cells. MPNST and MTT are both aggressive malignancies that most commonly arise from large deep neurofibromas in patients with neurofibromatosis type 1 (NF-1). However, sporadic non-NF-1 cases of MTT have also been reported in the literature. We present a case of a 50-year-old African American male with no stigmata of NF-1 who developed a large mass in a free flap on the right calf. The free flap had been placed by plastic surgery 15 years previously following open right tibial and fibular fractures associated with a large soft tissue defect. Biopsy of the enlarging mass, followed by wide surgical excision, confirmed the pathology to be MTT. Although the development of a high-grade soft tissue sarcoma has been previously reported as a late complication of radiation therapy following free flap reconstructions, we believe this is the first reported case of sarcomatous transformation arising in a vascularized, free muscle transfer.

  16. KANK1 inhibits cell growth by inducing apoptosis though regulating CXXC5 in human malignant peripheral nerve sheath tumors

    PubMed Central

    Cui, Zhibin; Shen, Yingjia; Chen, Kenny H.; Mittal, Suresh K.; Yang, Jer-Yen; Zhang, GuangJun

    2017-01-01

    Malignant peripheral nerve sheath tumors (MPNSTs) are a type of rare sarcomas with a poor prognosis due to its highly invasive nature and limited treatment options. Currently there is no targeted-cancer therapy for this type of malignancy. Thus, it is important to identify more cancer driver genes that may serve as targets of cancer therapy. Through comparative oncogenomics, we have found that KANK1 was a candidate tumor suppressor gene (TSG) for human MPNSTs. Although KANK1 is known as a cytoskeleton regulator, its tumorigenic function in MPNSTs remains largely unknown. In this study, we report that restoration of KANK1 in human MPNST cells inhibits cell growth both in human cell culture and xenograft mice by increasing apoptosis. Consistently, knockdown of KANK1 in neurofibroma cells promoted cell growth. Using RNA-seq analysis, we identified CXXC5 and other apoptosis-related genes, and demonstrated that CXXC5 is regulated by KANK1. Knockdown of CXXC5 was found to diminish KANK1-induced apoptosis in MPNST cells. Thus, KANK1 inhibits MPNST cell growth though CXXC5 mediated apoptosis. Our results suggest that KANK1 may function as a tumor suppressor in human MPNSTs, and thus it may be useful for targeted therapy. PMID:28067315

  17. Photothermal therapy improves the efficacy of a MEK inhibitor in neurofibromatosis type 1-associated malignant peripheral nerve sheath tumors

    NASA Astrophysics Data System (ADS)

    Sweeney, Elizabeth E.; Burga, Rachel A.; Li, Chaoyang; Zhu, Yuan; Fernandes, Rohan

    2016-11-01

    Malignant peripheral nerve sheath tumors (MPNSTs) are aggressive tumors with low survival rates and the leading cause of death in neurofibromatosis type 1 (NF1) patients under 40 years old. Surgical resection is the standard of care for MPNSTs, but is often incomplete and can generate loss of function, necessitating the development of novel treatment methods for this patient population. Here, we describe a novel combination therapy comprising MEK inhibition and nanoparticle-based photothermal therapy (PTT) for MPNSTs. MEK inhibitors block activity driven by Ras, an oncogene constitutively activated in NF1-associated MPNSTs, while PTT serves as a minimally invasive method to ablate cancer cells. Our rationale for combining these seemingly disparate techniques for MPNSTs is based on several reports demonstrating the efficacy of systemic chemotherapy with local PTT. We combine the MEK inhibitor, PD-0325901 (PD901), with Prussian blue nanoparticles (PBNPs) as PTT agents, to block MEK activity and simultaneously ablate MPNSTs. Our data demonstrate the synergistic effect of combining PD901 with PBNP-based PTT, which converge through the Ras pathway to generate apoptosis, necrosis, and decreased proliferation, thereby mitigating tumor growth and increasing survival of MPNST-bearing animals. Our results suggest the potential of this novel local-systemic combination “nanochemotherapy” for treating patients with MPNSTs.

  18. Primary Intraosseous Malignant Peripheral Nerve Sheath Tumor of the Medial Cuneiform: A Case Report and Review of the Literature.

    PubMed

    Muthusamy, Saravanaraja; Conway, Sheila A; Pitcher, J David; Temple, H Thomas

    Peripheral nerve sheath tumors (benign and malignant) usually arise in the soft tissues and are unusual in bone. Intraosseous peripheral nerve sheath tumors are usually benign and constitute approximately 0.2% of all bone tumors. Intraosseous malignant peripheral nerve sheath tumors (MPNSTs) are uncommon and usually result from secondary invasion. Only a few cases of primary intraosseous MPNSTs have been reported in published studies, and these were localized mostly in the mandible (approximately 50%) or maxilla, spine, and, occasionally, in the appendicular skeleton. To the best of our knowledge, we report the first case of primary intraosseous MPNST involving a midtarsal bone (medial cuneiform). The patient was a 62-year-old female who presented with pain and tenderness but without swelling. Imaging revealed nonspecific findings, and the preoperative computed tomography-guided biopsy findings were consistent with MPNST. The patient was treated with neoadjuvant radiotherapy, followed by wide local excision and allograft reconstruction. At the final follow-up examination (24 months), the graft had been incorporated without evidence of local recurrence or distant disease. The patient with primary intraosseous MPNST of the medial cuneiform described in the present report presented with nonspecific clinical and radiologic findings. Thus, a high index of suspicion and histopathologic examination, including immunohistochemistry, are necessary for an accurate diagnosis.

  19. Order-disorder phenomena in myelinated nerve sheaths: V. Effects of temperature on rat sciatic and optic nerves, and structural differences between the two types of nerve.

    PubMed

    Mateu, L; Luzzati, V; Vonasek, E; Mateu, E; Villegas, G M; Vargas, R

    1995-01-13

    We describe in this work X-ray scattering and electron microscope studies of rat sciatic and optic nerves as a function of temperature. The scattering experiments were analyzed as described in the previous papers of this series: a variety of parameters were determined, some of which characterize the lattice disorder, others the structure of the motif. The main results are the following. All the parameters determined by the X-ray scattering study vary with temperature and the temperature-dependence is specific for the type of nerve (sciatic or optic). Most of the disorder-related parameters display a minimum or a maximum in the vicinity of physiological temperature (38 degrees C in rat); this observation, strongly supported by the electron microscope study, shows that the degree of organization of myelin is highest near physiological temperature. The structure of the motif, as revealed by the electron density profile, is fairly different in the two types of nerves (in contrast with the assumption made by previous workers); the structure also varies with temperature and the temperature-induced alterations are nerve-type specific. In the two types of nerve the thickness of the lipid bilayer varies with temperature as expected for a lipid-containing system with hydrocarbon chains in the disordered conformation. In sciatic nerve the thickness of the (thinner) cytoplasmic polar layer, which is also the layer most affected by lattice disorder in this type of nerve, decreases dramatically with increasing temperature. In optic nerve, in which lattice disorder predominantly affects the extracellular layer, the thickness of both the cytoplasmic and the extracellular layer is barely affected by temperature.

  20. [Diagnostic difficulties in the laryngeal malignant peripheral nerve sheath tumor (MPNST)].

    PubMed

    Pabiszczak, Maciej; Woźniak, Aldona; Wierzbicka, Małgorzata; Leszczyńska, Małgorzata; Szyfter, Witold

    2004-01-01

    The malignant tumor deriving from the peripheral nerve sheet, previously described as malignant Schwannoma or neurosarcoma is extremely rare as malignancy localized in the larynx. The half of cases has been developing on the basis of neurofibromatosis in von Recklinghausen disease type I or seldom, type II. The high grade of malignancy end tendency to reccurences and distant metastases is typical for this tumors. The case of 64 year old man with larynx neurosarcoma was presented. The diagnostic difficulties were caused by clinical presentation of the smooth tumor covered by unchanged mucosa and typical histological features of the tumor. The final histological assessment was complemented by positive immunohistochemical reaction (antigens against protein S-100, NSE and PG 9.5).

  1. Modelling the effects of electric fields on nerve fibres: influence of the myelin sheath.

    PubMed

    Richardson, A G; McIntyre, C C; Grill, W M

    2000-07-01

    The excitation and conduction properties of computer-based cable models of mammalian motor nerve fibres, incorporating three different myelin representations, are compared. The three myelin representations are a perfectly insulating single cable (model A), a finite impedance single cable (model B) and a finite impedance double cable (model C). Extracellular stimulation of the three models is used to study their strength-duration and current-distance (I-X) relationships, conduction velocity (CV) and action potential shape. All three models have a chronaxie time that is within the experimental range. Models B and C have increased threshold currents compared with model A, but each model has slope to the I-X relationship that matches experimental results. Model B has a CV that matches experimental data, whereas the CV of models A and C are above and below the experimental range, respectively. Model C is able to produce a depolarising afterpotential (DAP), whereas models A and B exhibit hyperpolarising afterpotentials. Models A and B are determined to be the preferred models when low-frequency stimulation (< approximately 25 Hz) is used, owing to their efficiency and accurate excitation and conduction properties. For high frequency stimulation (approximately 25 Hz and greater), model C, with its ability to produce a DAP, is necessary accurately to simulate excitation behaviour.

  2. Optimal optic nerve sheath diameter threshold for the identification of elevated opening pressure on lumbar puncture in a Chinese population.

    PubMed

    Wang, Lijuan; Feng, Liangshu; Yao, Yan; Wang, Yuzhi; Chen, Ying; Feng, Jiachun; Xing, Yingqi

    2015-01-01

    Ultrasonography of the optic nerve sheath diameter (ONSD) is a non-invasive and rapid method that might be helpful in the identification of increased intracranial pressure (ICP). The use of an ONSD greater than 5 mm on ultrasound as an indicator of increased ICP in a Caucasian population has been studied. However, the cut-off point of this predictor in Chinese patients has not been established. Thus, we conducted this study to identify the ONSD criterion for the detection of elevated opening pressure on lumbar puncture (LP) in a Chinese population and to investigate the influencing factors. This study was a blind cross-sectional study. Patients who presented with suspected increased ICP were included. The opening pressure on LP of each participant was confirmed. We analyzed the clinical differences between the groups of patients with abnormal and normal opening pressures on LP. A receiver operating characteristic curve was constructed to determine the ONSD cut-off point for the identification of abnormal opening pressure on LP. In total, 279 patients were recruited, and 101 patients presented with elevated opening pressure on LP. ONSD was a significant independent predictor of elevated opening pressure on LP (p<0.001). However, no statistical significance was observed regarding the factors that might have affected this relationship including gender, age, body mass index, waistline, head circumference, hypertension and pathological subtype. The ONSD cut-off point for the identification of elevated opening pressure on LP was 4.1 mm; this cut-off yielded a sensitivity of 95% and a specificity of 92%. ONSD is a strong and accurate predictor of elevated opening pressure on LP. The cut-off point of this predictor in a Chinese population was remarkably lower than that found in a Caucasian population. Thus, ethnic differences should be noted when using the ONSD as an indicator of increased ICP.

  3. Doxycycline potentiates antitumor effect of 5-aminolevulinic acid-mediated photodynamic therapy in malignant peripheral nerve sheath tumor cells

    PubMed Central

    Lee, Ming-Jen; Hung, Shih-Hsuan; Huang, Mu-Ching; Tsai, Tsuimin

    2017-01-01

    Neurofibromatosis type 1 (NF1) is one of the most common neurocutaneous disorders. Some NF1 patients develop benign large plexiform neurofibroma(s) at birth, which can then transform into a malignant peripheral nerve sheath tumor (MPNST). There is no curative treatment for this rapidly progressive and easily metastatic neurofibrosarcoma. Photodynamic therapy (PDT) has been developed as an anti-cancer treatment, and 5-aminolevulinic (ALA) mediated PDT (ALA-PDT) has been used to treat cutaneous skin and oral neoplasms. Doxycycline, a tetracycline derivative, can substantially reduce the tumor burden in human and animal models, in addition to its antimicrobial effects. The purpose of this study was to evaluate the effect and to investigate the mechanism of action of combined doxycycline and ALA-PDT treatment of MPNST cells. An 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay showed that the combination of ALA-PDT and doxycycline significantly reduce MPNST survival rate, compared to cells treated with each therapy alone. Isobologram analysis showed that the combined treatment had a synergistic effect. The increased cytotoxic activity could be seen by an increase in cellular protoporphyrin IX (PpIX) accumulation. Furthermore, we found that the higher retention of PpIX was mainly due to increasing ALA uptake, rather than activity changes of the enzymes porphobilinogen deaminase and ferrochelatase. The combined treatment inhibited tumor growth in different tumor cell lines, but not in normal human Schwann cells or fibroblasts. Similarly, a synergistic interaction was also found in cells treated with ALA-PDT combined with minocycline, but not tetracycline. In summary, doxycycline can potentiate the effect of ALA-PDT to kill tumor cells. This increased potency allows for a dose reduction of doxycycline and photodynamic radiation, reducing the occurrence of toxic side effects in vivo. PMID:28558025

  4. Malignant peripheral nerve sheath tumor (MPNST) arising in diffuse-type neurofibroma: clinicopathologic characterization in a series of 9 cases.

    PubMed

    Schaefer, Inga-Marie; Fletcher, Christopher D M

    2015-09-01

    Diffuse-type neurofibroma, an uncommon variant of neurofibroma, is associated with neurofibromatosis type 1 in ∼60% of cases. Typically presenting in young adults as ill-defined plaque-like dermal/subcutaneous thickening, most cases are located on the trunk or the head and neck region. Malignant transformation is extremely rare. Nine cases of malignant peripheral nerve sheath tumor (MPNST) arising in diffuse-type neurofibroma (identified in consult files) are described, including clinicopathologic features and follow-up. Five patients were male and 4 female, aged 31 to 59 years (median 49 y). All diffuse-type neurofibromas contained Meissner corpuscles, with tumor sizes ranging between 3.6 and 45 cm (median, 7.4 cm). Five patients had a clinical history of neurofibromatosis type 1, and 1 had Klippel-Trénaunay-Weber syndrome. Six tumors arose on the trunk and 1 each on the leg, arm, and scalp. Increased cellularity, nuclear atypia, and mitoses (range, 1 to 63/50 high-power fields) indicated transition to MPNST, classified as low grade in 5, intermediate to high grade in 1, and high grade in 3 cases, 1 of which exhibited heterologous angiosarcomatous differentiation. S-100 expression was quite strong and diffuse in the neurofibroma components and less extensive or weaker in MPNST. Follow-up, available for all patients (median, 80.5 mo, except 1 recent case), revealed that 1 patient developed local recurrence after 9 months; 1 with metastases at the time of initial diagnosis died 1 month after tumor resection. All other patients were alive without evidence of disease at 15 to 145 months (median, 83 mo). Diffuse-type neurofibroma may show transformation to MPNST in very rare instances. It is important to be aware of possible malignant change, requiring thorough sampling of resection specimens and long-term clinical follow-up of patients with unexcised lesions.

  5. Dual mTORC1/2 inhibition induces anti-proliferative effect in NF1-associated plexiform neurofibroma and malignant peripheral nerve sheath tumor cells.

    PubMed

    Varin, Jennifer; Poulain, Laury; Hivelin, Mikael; Nusbaum, Patrick; Hubas, Arnaud; Laurendeau, Ingrid; Lantieri, Laurent; Wolkenstein, Pierre; Vidaud, Michel; Pasmant, Eric; Chapuis, Nicolas; Parfait, Béatrice

    2016-06-14

    Approximately 30-50% of individuals with Neurofibromatosis type 1 develop benign peripheral nerve sheath tumors, called plexiform neurofibromas (PNFs). PNFs can undergo malignant transformation to highly metastatic malignant peripheral nerve sheath tumors (MPNSTs) in 5-10% of NF1 patients, with poor prognosis. No effective systemic therapy is currently available for unresectable tumors. In tumors, the NF1 gene deficiency leads to Ras hyperactivation causing the subsequent activation of the AKT/mTOR and Raf/MEK/ERK pathways and inducing multiple cellular responses including cell proliferation. In this study, three NF1-null MPNST-derived cell lines (90-8, 88-14 and 96-2), STS26T sporadic MPNST cell line and PNF-derived primary Schwann cells were used to test responses to AZD8055, an ATP-competitive "active-site" mTOR inhibitor. In contrast to rapamycin treatment which only partially affected mTORC1 signaling, AZD8055 induced a strong inhibition of mTORC1 and mTORC2 signaling in MPNST-derived cell lines and PNF-derived Schwann cells. AZD8055 induced full blockade of mTORC1 leading to an efficient decrease of global protein synthesis. A higher cytotoxic effect was observed with AZD8055 compared to rapamycin in the NF1-null MPNST-derived cell lines with IC50 ranging from 70 to 140 nM and antiproliferative effect was confirmed in PNF-derived Schwann cells. Cell migration was impaired by AZD8055 treatment and cell cycle analysis showed a G0/G1 arrest. Combined effects of AZD8055 and PD0325901 MEK inhibitor as well as BRD4 (BromoDomain-containing protein 4) inhibitors showed a synergistic antiproliferative effect. These data suggest that NF1-associated peripheral nerve sheath tumors are an ideal target for AZD8055 as a single molecule or in combined therapies.

  6. Dual mTORC1/2 inhibition induces anti-proliferative effect in NF1-associated plexiform neurofibroma and malignant peripheral nerve sheath tumor cells

    PubMed Central

    Hivelin, Mikael; Nusbaum, Patrick; Hubas, Arnaud; Laurendeau, Ingrid; Lantieri, Laurent; Wolkenstein, Pierre; Vidaud, Michel; Pasmant, Eric; Chapuis, Nicolas; Parfait, Béatrice

    2016-01-01

    Approximately 30-50% of individuals with Neurofibromatosis type 1 develop benign peripheral nerve sheath tumors, called plexiform neurofibromas (PNFs). PNFs can undergo malignant transformation to highly metastatic malignant peripheral nerve sheath tumors (MPNSTs) in 5-10% of NF1 patients, with poor prognosis. No effective systemic therapy is currently available for unresectable tumors. In tumors, the NF1 gene deficiency leads to Ras hyperactivation causing the subsequent activation of the AKT/mTOR and Raf/MEK/ERK pathways and inducing multiple cellular responses including cell proliferation. In this study, three NF1-null MPNST-derived cell lines (90-8, 88-14 and 96-2), STS26T sporadic MPNST cell line and PNF-derived primary Schwann cells were used to test responses to AZD8055, an ATP-competitive “active-site” mTOR inhibitor. In contrast to rapamycin treatment which only partially affected mTORC1 signaling, AZD8055 induced a strong inhibition of mTORC1 and mTORC2 signaling in MPNST-derived cell lines and PNF-derived Schwann cells. AZD8055 induced full blockade of mTORC1 leading to an efficient decrease of global protein synthesis. A higher cytotoxic effect was observed with AZD8055 compared to rapamycin in the NF1-null MPNST-derived cell lines with IC50 ranging from 70 to 140 nM and antiproliferative effect was confirmed in PNF-derived Schwann cells. Cell migration was impaired by AZD8055 treatment and cell cycle analysis showed a G0/G1 arrest. Combined effects of AZD8055 and PD0325901 MEK inhibitor as well as BRD4 (BromoDomain-containing protein 4) inhibitors showed a synergistic antiproliferative effect. These data suggest that NF1-associated peripheral nerve sheath tumors are an ideal target for AZD8055 as a single molecule or in combined therapies. PMID:26840085

  7. Intraoperative monitoring during decompression of the spinal cord and spinal nerves using transcranial motor-evoked potentials: The law of twenty percent.

    PubMed

    Tanaka, Satoshi; Hirao, Jun; Oka, Hidehiro; Akimoto, Jiro; Takanashi, Junko; Yamada, Junichi

    2015-09-01

    Motor-evoked potential (MEP) monitoring was performed during 196 consecutive spinal (79 cervical and 117 lumbar) surgeries for the decompression of compressive spinal and spinal nerve diseases. MEP monitoring in spinal surgery has been considered sensitive to predict postoperative neurological recovery. In this series, transcranial stimulation consisted of trains of five pulses at a constant voltage (200-600 V). For the normalization of MEP, we recorded compound muscle action potentials (CMAP) after peripheral nerve stimulation, usually on the median nerve at the wrist 2 seconds before or after each transcranial stimulation of the motor area, for all operations. The sensitivity and specificity of MEP monitoring was 100% and 97.4%, respectively, or 96.9% with or without CMAP compensation (if the threshold of postoperative motor palsy was defined as 20% relative amplitude rate [RAR]). The mean RAR after CMAP normalization, of the most affected muscle in the patient group with excellent postoperative results (recovery rate of a Japan Orthopedic Association score of more than 50%) was significantly higher than that in the other groups (p=0.0224). All patients with an amplitude increase rate (AIR) with CMAP normalization of more than 20% achieved neurological recovery postoperatively. Our results suggest that if the RAR is more than 20%, postoperative motor palsy can be avoided in spinal surgery. If the AIR with normalization by CMAP after peripheral nerve stimulation is more than 20%, neurological recovery can be expected in spinal surgery.

  8. Acute Improvement in Intraoperative EMG Following Common Fibular Nerve Decompression in Patients with Symptomatic Diabetic Sensorimotor Peripheral Neuropathy: 1. EMG Results.

    PubMed

    Anderson, James C; Nickerson, D Scott; Tracy, Brian L; Paxton, Roger J; Yamasaki, Dwayne S

    2017-09-01

    Background and Study Aims Electromyographic (EMG) recordings of the fibularis longus (FL) and tibialis anterior (TA) muscles were performed intraoperatively during common fibular nerve (CFN) nerve decompression (ND) in patients with symptomatic diabetic sensorimotor peripheral neuropathy (DSPN) and clinical nerve compression. Materials and Methods Forty-six legs in 40 patients underwent surgical ND by external neurolysis; FL and TA muscles were monitored intraoperatively. Evoked EMGs were recorded just prior to and within 1 minute after ND. Results Thirty-eight legs (82.6%) demonstrated EMG improvement 1 minute after ND. Sixty muscles (31 FL, 29 TA) were monitored, with 44 (73.3%) improving in EMG amplitude. Mean change in EMG amplitude represented a 73.6% improvement (p < 0.0001). Changes in EMG amplitudes correlated with visual analog scale pain improvement (p = 0.03). Conclusion This is the first report of acute changes in objective EMG responses during ND of CFN in DSPN patients and demonstrates that patients with symptomatic DSPN and clinical nerve entrapment have latent but functional axons that surgical ND can improve immediately. Georg Thieme Verlag KG Stuttgart · New York.

  9. Optic nerve sheath diameter sonography for the diagnosis of increased intracranial pressure: a systematic review and meta-analysis protocol.

    PubMed

    Koziarz, Alex; Sne, Niv; Kegel, Fraser; Alhazzani, Waleed; Nath, Siddharth; Badhiwala, Jetan H; Rice, Timothy; Engels, Paul; Samir, Faidi; Healey, Andrew; Kahnamoui, Kamyar; Banfield, Laura; Sharma, Sunjay; Reddy, Kesava; Hawryluk, Gregory W J; Kirkpatrick, Andrew W; Almenawer, Saleh A

    2017-08-11

    Increased intracranial pressure (ICP) is a significant neurological issue that may lead to permanent neurological sequelae. When evaluating patients with traumatic brain injury, it is crucial to identify those with high ICP in order to expedite ICP lowering measures and maintain adequate cerebral perfusion. Several measures are used to recognise patients with increased ICP including CT scan, MRI, ICP monitor, and lumbar puncture (LP). However, these tests can be invasive, associated with radiation exposure, contraindicated, or not readily available. Ultrasonography measurement of the optic nerve sheath diameter (ONSD) is proposed as a non-invasive and quick measure to identify high ICP. The aim of this systematic review and meta-analysis will be to examine the accuracy of ONSD sonography for increased ICP diagnosis. We will include published and unpublished randomised controlled trials, observational studies, and abstracts, with no publication type or language restrictions. Search strategies will be designed to peruse the MEDLINE, Embase, Web of Science, WHO Clinical Trials, ClinicalTrials.gov, CINAHL, and the Cochrane Library databases. We will also implement strategies to search grey literature. Two reviewers will independently complete data abstraction and conduct quality assessment. Included studies will be assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool. We will construct the hierarchical summary receiver operating characteristic curve for included studies and pool sensitivity and specificity using the bivariate model. We also plan to conduct prespecified subgroup analyses to explore heterogeneity. The overall quality of evidence will be rated using Grading of Recommendations, Assessment, Development and Evaluations (GRADE). Research ethics board approval is not required for this study as it draws from published data and raises no concerns related to patient privacy. This review will provide a comprehensive assessment of

  10. Somatostatin Receptor SPECT/CT using 99mTc Labeled HYNIC-TOC Aids in Diagnosis of Primary Optic Nerve Sheath Meningioma

    PubMed Central

    Chandra, Piyush; Purandare, Nilendu; Shah, Sneha; Agrawal, Archi; Rangarajan, Venkatesh

    2017-01-01

    Primary optic nerve sheath meningiomas (ONSM) are rare, benign and slow growing tumor involving the intra-orbital/intra-canalicular segment of the optic nerve. Untreated, they can potentially lead to visual deterioration. Magnetic resonance (MR) is the gold standard imaging modality for diagnosing the entity. Often, a clinical dilemma exists to narrow the differential diagnosis of an enhancing intra-orbital mass on MR. Molecular imaging provides a high degree of precision in diagnosing meningioma in view of relatively high levels of somatostatin receptor expression by these tumors. The following case demonstrates the potential clinical utility of somatostatin receptor SPECT using 99mTc- labeled HYNIC-TOC in clinical diagnosis of ONSM. PMID:28242992

  11. Somatostatin Receptor SPECT/CT using (99m)Tc Labeled HYNIC-TOC Aids in Diagnosis of Primary Optic Nerve Sheath Meningioma.

    PubMed

    Chandra, Piyush; Purandare, Nilendu; Shah, Sneha; Agrawal, Archi; Rangarajan, Venkatesh

    2017-01-01

    Primary optic nerve sheath meningiomas (ONSM) are rare, benign and slow growing tumor involving the intra-orbital/intra-canalicular segment of the optic nerve. Untreated, they can potentially lead to visual deterioration. Magnetic resonance (MR) is the gold standard imaging modality for diagnosing the entity. Often, a clinical dilemma exists to narrow the differential diagnosis of an enhancing intra-orbital mass on MR. Molecular imaging provides a high degree of precision in diagnosing meningioma in view of relatively high levels of somatostatin receptor expression by these tumors. The following case demonstrates the potential clinical utility of somatostatin receptor SPECT using (99m)Tc- labeled HYNIC-TOC in clinical diagnosis of ONSM.

  12. Decompression and decompression sickness.

    PubMed

    Mahon, Richard T; Regis, David P

    2014-07-01

    The ever-present desire of humankind to explore new limits introduced us to the syndrome of decompression sickness (DCS). This broad overview of DCS is aimed at its pathophysiology and basics of therapeutic strategies. After a brief explanation of decompression theory, historical vignettes will serve to inform the practical application of our increasing understanding of DCS risks. The pathophysiology, current practices, role of bubble monitoring, risk factors, and potential long-term effects of DCS are also discussed. The goal is to explain the current state of DCS understanding in the context of a robust observational and empirical history. However, DCS remains a syndrome consisting of a constellation of symptoms following a change in ambient pressure. Though great strides have been made, significant knowledge gaps remain. If the coming years advance the field even a fraction of what its predecessors accomplished, the health and safety of those who endeavor in the environment of changing pressures most certainly will be improved.

  13. Classic Ras Proteins Promote Proliferation and Survival Via Distinct Phosphoproteome Alterations in Neurofibromin-Null Malignant Peripheral Nerve Sheath Tumor Cells

    PubMed Central

    Brossier, Nicole M.; Prechtl, Amanda M.; Longo, Jody Fromm; Barnes, Stephen; Wilson, Landon S.; Byer, Stephanie J.; Brosius, Stephanie N.; Carroll, Steven L.

    2015-01-01

    Neurofibromin, the tumor suppressor encoded by the neurofibromatosis type 1 (NF1) gene, potentially suppresses the activation of H-Ras, N-Ras and K-Ras. However, it is not known whether these classic Ras proteins are hyperactivated in NF1-null nerve sheath tumors, how they contribute to tumorigenesis and what signaling pathways mediate their effects. Here we show that H-Ras, N-Ras and K-Ras are coexpressed with their activators, (guanine nucleotide exchange factors), in neurofibromin-null malignant peripheral nerve sheath tumor (MPNST) cells and that all 3 Ras proteins are activated. Dominant negative (DN) H-Ras, a pan-inhibitor of the classic Ras family, inhibited MPNST proliferation and survival, but not migration. However, NF1-null MPNST cells were variably dependent on individual Ras proteins. In some lines, ablation of H-Ras, N-Ras and/or K-Ras inhibited mitogenesis. In others, ablation of a single Ras protein had no effect on proliferation; in these lines, ablation of a single Ras protein resulted in compensatory increases in the activation and/or expression of other Ras proteins. Using mass spectrometry-based phosphoproteomics, we identified 7 signaling networks affecting morphology, proliferation and survival that are regulated by DN H-Ras. Thus, neurofibromin loss activates multiple classic Ras proteins that promote proliferation and survival by regulating several distinct signaling cascades. PMID:25946318

  14. Effect of Positive End-Expiratory Pressure on the Sonographic Optic Nerve Sheath Diameter as a Surrogate for Intracranial Pressure during Robot-Assisted Laparoscopic Prostatectomy: A Randomized Controlled Trial

    PubMed Central

    Chin, Ji-Hyun; Kim, Wook-Jong; Lee, Joonho; Han, Yun A.; Lim, Jinwook; Hwang, Jai-Hyun; Cho, Seong-Sik

    2017-01-01

    Background Positive end-expiratory pressure (PEEP) can increase intracranial pressure. Pneumoperitoneum and the Trendelenburg position are associated with an increased intracranial pressure. We investigated whether PEEP ventilation could additionally influence the sonographic optic nerve sheath diameter as a surrogate for intracranial pressure during pneumoperitoneum combined with the Trendelenburg position in patients undergoing robot-assisted laparoscopic prostatectomy. Methods After anesthetic induction, 38 patients were randomly allocated to a low tidal volume ventilation (8 ml/kg) without PEEP group (zero end-expiratory pressure [ZEEP] group, n = 19) or low tidal volume ventilation with 8 cmH2O PEEP group (PEEP group, n = 19). The sonographic optic nerve sheath diameter was measured prior to skin incision, 5 min and 30 min after pneumoperitoneum and the Trendelenburg position, and at the end of surgery. The study endpoint was the difference in the sonographic optic nerve sheath diameter 5 min after pneumoperitoneum and the Trendelenburg position between the ZEEP and PEEP groups. Results Optic nerve sheath diameters 5 min after pneumoperitoneum and the Trendelenburg position did not significantly differ between the groups [least square mean (95% confidence interval); 4.8 (4.6–4.9) mm vs 4.8 (4.7–5.0) mm, P = 0.618]. Optic nerve sheath diameters 30 min after pneumoperitoneum and the Trendelenburg position also did not differ between the groups [least square mean (95% confidence interval); 4.5 (4.3–4.6) mm vs 4.5 (4.4–4.6) mm, P = 0.733]. Conclusions An 8 cmH2O PEEP application under low tidal volume ventilation does not induce an increase in the optic nerve sheath diameter during pneumoperitoneum combined with the steep Trendelenburg position, suggesting that there might be no detrimental effects of PEEP on the intracranial pressure during robot-assisted laparoscopic prostatectomy. Trial Registration ClinicalTrial.gov NCT02516566 PMID:28107408

  15. Nerve Injuries of the Upper Extremity

    MedlinePlus

    ... of individual nerve fibers and surrounding outer sheath (“insulation”) Figure 2: Nerve repair with realignment of bundles © ... of individual nerve fibers and surrounding outer sheath insulation Figure 2 - Nerve repair with realignment of bundles ...

  16. Convection-Enhanced Delivery (CED) in an Animal Model of Malignant Peripheral Nerve Sheath Tumors and Plexiform Neurofibromas

    DTIC Science & Technology

    2013-02-01

    sheath tumors or plexiform neurofibromas. References: Perrin GQ, Fishbein L, Thomson SA, et al., Plexiform-like neurofibromas develop in the...mouse by intraneural xenograft of an NF1 tumor-derived Schwann cell line. J Neurosci Res, 2007. 85(6): p. 1347-1357. 3 Perrin GQ, Li H, Fishbein L

  17. Clinical and imaging findings, treatments, and outcomes in 27 dogs with imaging diagnosed trigeminal nerve sheath tumors: A multi-center study.

    PubMed

    Swift, Katie E; McGrath, Stephanie; Nolan, Michael W; Young, Martin; Reese, Michael; Rao, Sangeeta; Randall, Elissa; Leary, Del; LaRue, Susan

    2017-07-31

    The clinical behavior of canine trigeminal nerve sheath tumors and benefits of previously reported treatments are incompletely defined. Aims of this retrospective, multicenter, observational study were to describe clinical signs, tumor localization characteristics, treatments, and clinical outcomes in a group of dogs with this neoplasm. Databases at four hospitals were reviewed for dogs with a trigeminal nerve sheath tumor diagnosis, magnetic resonance imaging (MRI) studies, and presentation between 2004 and 2014. A single observer recorded medical record findings and two observers recorded MRI characteristics by consensus. A total of 27 dogs met inclusion criteria (15 treated with stereotactic radiation therapy and 12 unirradiated). Two unirradiated dogs were excluded from outcome analyses. The most common presenting signs were masticatory muscle atrophy (26 dogs), neurologic signs referable to intracranial disease (13), and ocular disease (12). Based on MRI findings, all dogs had disease extending centrally at the level of the brainstem. The most commonly affected trigeminal nerve branches were the mandibular (26 dogs), maxillary (22), and ophthalmic (10). Of 15 dogs treated with stereotactic radiation therapy, one had improved muscle atrophy, and six had poor ocular health after treatment. Neurologic signs improved in 4/5 dogs with intracranial signs. Overall median survival time for the 10 unirradiated dogs with available follow-up was 12 days and 441 days for the 15 stereotactic radiation therapy dogs. Mean survival times between these groups were not significantly different (mean 95% CI for unirradiated dogs was 44-424 days and mean 95% CI for stereotactic radiation therapy dogs was 260-518 days). © 2017 American College of Veterinary Radiology.

  18. Comprehensive adipocytic and neurogenic tissue microarray analysis of NY-ESO-1 expression - a promising immunotherapy target in malignant peripheral nerve sheath tumor and liposarcoma.

    PubMed

    Shurell, Elizabeth; Vergara-Lluri, Maria E; Li, Yunfeng; Crompton, Joseph G; Singh, Arun; Bernthal, Nicholas; Wu, Hong; Eilber, Fritz C; Dry, Sarah M

    2016-11-08

    Immunotherapy targeting cancer-testis antigen NY-ESO-1 shows promise for tumors with poor response to chemoradiation. Malignant peripheral nerve sheath tumors (MPNSTs) and liposarcomas (LPS) are chemoresistant and have few effective treatment options. Materials Methods: Using a comprehensive tissue microarray (TMA) of both benign and malignant tumors in primary, recurrent, and metastatic samples, we examined NY-ESO-1 expression in peripheral nerve sheath tumor (PNST) and adipocytic tumors. The PNST TMA included 42 MPNSTs (spontaneous n = 26, NF1-associated n = 16), 35 neurofibromas (spontaneous n = 22, NF-1 associated n = 13), 11 schwannomas, and 18 normal nerves. The LPS TMA included 48 well-differentiated/dedifferentiated (WD/DD) LPS, 13 myxoid/round cell LPS, 3 pleomorphic LPS, 8 lipomas, 1 myelolipoma, and 3 normal adipocytic tissue samples. Stained in triplicate, NY-ESO-1 intensity and density were scored. NY-ESO-1 expression was exclusive to malignant tumors. 100% of myxoid/round cell LPS demonstrated NY-ESO-1 expression, while only 6% of WD/DD LPS showed protein expression, one of which was WD LPS. Of MPNST, 4/26 (15%) spontaneous and 2/16 (12%) NF1-associated MPNSTs demonstrated NY-ESO-1 expression. Strong NY-ESO-1 expression was observed in myxoid/round cell and dedifferentiated LPS, and MPNST in primary, neoadjuvant, and metastatic settings. We found higher prevalence of NY-ESO-1 expression in MPNSTs than previously reported, highlighting a subset of MPNST patients who may benefit from immunotherapy. This study expands our understanding of NY-ESO-1 in WD/DD LPS and is the first demonstration of staining in a WD LPS and metastatic/recurrent myxoid/round cell LPS. These results suggest immunotherapy targeting NY-ESO-1 may benefit patients with aggressive tumors resistant to conventional therapy.

  19. Comprehensive adipocytic and neurogenic tissue microarray analysis of NY-ESO-1 expression - a promising immunotherapy target in malignant peripheral nerve sheath tumor and liposarcoma

    PubMed Central

    Shurell, Elizabeth; Vergara-Lluri, Maria E.; Li, Yunfeng; Crompton, Joseph G.; Singh, Arun; Bernthal, Nicholas; Wu, Hong; Eilber, Fritz C.; Dry, Sarah M.

    2016-01-01

    Background Immunotherapy targeting cancer-testis antigen NY-ESO-1 shows promise for tumors with poor response to chemoradiation. Malignant peripheral nerve sheath tumors (MPNSTs) and liposarcomas (LPS) are chemoresistant and have few effective treatment options. Materials Methods Using a comprehensive tissue microarray (TMA) of both benign and malignant tumors in primary, recurrent, and metastatic samples, we examined NY-ESO-1 expression in peripheral nerve sheath tumor (PNST) and adipocytic tumors. The PNST TMA included 42 MPNSTs (spontaneous n = 26, NF1-associated n = 16), 35 neurofibromas (spontaneous n = 22, NF-1 associated n = 13), 11 schwannomas, and 18 normal nerves. The LPS TMA included 48 well-differentiated/dedifferentiated (WD/DD) LPS, 13 myxoid/round cell LPS, 3 pleomorphic LPS, 8 lipomas, 1 myelolipoma, and 3 normal adipocytic tissue samples. Stained in triplicate, NY-ESO-1 intensity and density were scored. Results NY-ESO-1 expression was exclusive to malignant tumors. 100% of myxoid/round cell LPS demonstrated NY-ESO-1 expression, while only 6% of WD/DD LPS showed protein expression, one of which was WD LPS. Of MPNST, 4/26 (15%) spontaneous and 2/16 (12%) NF1-associated MPNSTs demonstrated NY-ESO-1 expression. Strong NY-ESO-1 expression was observed in myxoid/round cell and dedifferentiated LPS, and MPNST in primary, neoadjuvant, and metastatic settings. Conclusions We found higher prevalence of NY-ESO-1 expression in MPNSTs than previously reported, highlighting a subset of MPNST patients who may benefit from immunotherapy. This study expands our understanding of NY-ESO-1 in WD/DD LPS and is the first demonstration of staining in a WD LPS and metastatic/recurrent myxoid/round cell LPS. These results suggest immunotherapy targeting NY-ESO-1 may benefit patients with aggressive tumors resistant to conventional therapy. PMID:27655679

  20. Characterizing the immune microenvironment of malignant peripheral nerve sheath tumor by PD-L1 expression and presence of CD8+ tumor infiltrating lymphocytes

    PubMed Central

    Shurell, Elizabeth; Singh, Arun S.; Crompton, Joseph G.; Jensen, Sarah; Li, Yunfeng; Dry, Sarah; Nelson, Scott; Chmielowski, Bartosz; Bernthal, Nicholas; Federman, Noah; Tumeh, Paul; Eilber, Fritz C.

    2016-01-01

    Background Malignant peripheral nerve sheath tumor (MPNST) is an aggressive sarcoma with few treatment options. Tumor immune state has not been characterized in MPNST, and is important in determining response to immune checkpoint blockade. Our aim was to evaluate the expression of programmed death-ligand 1 (PD-L1), programmed cell death protein 1 (PD-1), and presence of CD8+ tumor infiltrating lymphocytes (TILs) in MPNST, and correlate these findings with clinical behavior and outcome. Results PD-L1 staining of at least 1% was seen in 0/20 nerves, 2/68 benign lesions and 9/53 MPNST. Two of 68 benign lesions and 7/53 (13%) MPNST had at least 5% PD-L1 staining. CD8 staining of at least 5% was seen in 1/20 (5%) nerves, 45/68 (66%) benign lesions and 30/53 (57%) MPNST. PD-L1 was statistically more prevalent in MPNST than both nerves and benign lesions (p=0.049 and p=0.008, respectively). Expression of PD-1 was absent in all tissue specimens. There was no correlation of PD-L1 or CD8 expression with disease state (primary versus metastatic) or patient survival. Methods A comprehensive PNST tissue microarray was created from 141 surgical specimens including primary, recurrent, and metastatic MPNST (n=53), neurofibromas (n=57), schwannoma (n=11), and normal nerve (n=20). Cores were stained in triplicate for PD-L1, PD-1, and CD8, and expression compared between tumor types. These data were then examined for survival correlates in 35 patients with primary MPNST. Conclusions MPNST is characterized by low PD-L1 and absent PD-1 expression with significant CD8+ TIL presence. MPNST immune microenvironment does not correlate with patient outcome. PMID:27588404

  1. Pelvic Neuralgias by Neuro-Vascular Entrapment: Anatomical Findings in a Series of 97 Consecutive Patients Treated by Laparoscopic Nerve Decompression.

    PubMed

    Possover, Marc; Forman, Axel

    2015-11-01

    Some patients have pelvic, pudendal, or low lumbar pain radiating into the legs that is worse while sitting but differs from pudendal neuralgia. The purpose of this study was to present a new clinical entity of neuropathic pelvic pain by pelvic neuro-vascular entrapment. To report about the locations of predilection for pelvic neurovascular entrapment. Prospective cohort pre- and post-intervention. University referral unit specializing in advanced gynecological surgery and neuropelveology. Patients, Intervention: In a prospective study, 97 patients presenting with intractable pelvic neuropathic pain (pudendal pain, gluteal pain, vulvodynia, coccygodynia, and sciatic pain) underwent laparoscopic exploration with decompression of compressed pelvic somatic nerves. The population included 76 (78.3%) women and 21 men. Indication for laparoscopic exploration of pelvic nerves suspected to be involved in pain has been indicated after neuropelveological work up, pelvic neuro-magnetic resonance imaging (MRI) and Doppler-sonography. Pain evolution was recorded over 2 years after the procedure. Three entities were isolated: pudendal neuralgie by compression at the less sciatic notch, sacral radiculopathy at S2-4 by compression at the infracardinal level of the sacral plexus, and sciatica L5-S1/2 by compression at the greater sciatic notch. Pain was worse sitting (98%), during menstrual bleeding in women, and during Valsalva maneuver, but the pain did not wake the patients up at night and was not accompanied by neurologic dysfunctions. A decrease in VAS scores (> 50%) at 2 years follow-up was observed in 86 patients (88.6%). Neuro-vascular entrapment is a pathophysiologic phenomenon implicated in several pelvic neuropathies. The most common are L5-S1 sciatica, pudendal neuralgia, and sacral radiculopathy. After intraoperative confirmation, laparoscopic exploration of the entire sacral plexus is essential to diagnose conflict. Laparoscopic decompression is a treatment of choice

  2. Triterpenoid saponin flaccidoside II from Anemone flaccida triggers apoptosis of NF1-associated malignant peripheral nerve sheath tumors via the MAPK-HO-1 pathway

    PubMed Central

    Han, Lin-tao; Fang, Yin; Cao, Yan; Wu, Feng-hua; Liu, E; Mo, Guo-yan; Huang, Fang

    2016-01-01

    Malignant peripheral nerve sheath tumors (MPNSTs) are highly aggressive soft tissue neoplasms that are extremely rare and are frequently associated with neurofibromatosis type 1 patients. MPNSTs are typically fatal, and there is no effective treatment so far. In our previous study, we showed that flaccidoside II, one of the triterpenoid saponins isolated from Anemone flaccida Fr. Schmidt, has antitumor potential by inducing apoptosis. In the present study, we found that flaccidoside II inhibits proliferation and facilitates apoptosis in MPNST cell lines ST88-14 and S462. Furthermore, this study provides a mechanism by which the downregulation of heme oxygenase-1 via extracellular signal-regulated kinase-1/2 and p38 mitogen-activated protein kinase pathways is involved in the apoptotic role of flaccidoside II. This study suggested the potential of flaccidoside II as a novel pharmacotherapeutic approach for MPNSTs. PMID:27103823

  3. Successful treatment with doxorubicin and ifosfamide for mediastinal malignant peripheral nerve sheath tumor with loss of H3K27me3 expression.

    PubMed

    Seno, Noriko; Fukushima, Toshirou; Gomi, Daisuke; Kobayashi, Takashi; Sekiguchi, Nodoka; Matsushita, Hidehiro; Ozawa, Takesumi; Tsukahara, Yoshiko; Mamiya, Keiko; Koizumi, Tomonobu; Sano, Kenji

    2017-09-06

    Malignant peripheral nerve sheath tumor (MPNST) in the thorax is an extremely rare disease, and half of all cases of MPNST are associated with neurofibromatosis type I. Sporadic intrathoracic MPNST is difficult to diagnose and treat. Because of the rarity of intrathoracic MPNST, the optimal method of diagnosis and the efficacy of chemotherapy are unknown. Herein, we present a case of inoperable mediastinal MPNST, in which the diagnosis was immunohistochemically made by the loss of H3K27me3 expression in a transbronchial needle biopsy specimen. The patient showed a good response to doxorubicin plus ifosfamide chemotherapy. The present case highlights that MPNST should be included in the differential diagnosis of non-posterior mediastinum thoracic lesions, and that appropriate diagnosis and treatment for intrathoracic MPNST should be considered in patients with a thoracic mass. © 2017 The Authors. Thoracic Cancer published by China Lung Oncology Group and John Wiley & Sons Australia, Ltd.

  4. Overexpression of PDGFRA cooperates with loss of NF1 and p53 to accelerate the molecular pathogenesis of malignant peripheral nerve sheath tumors.

    PubMed

    Ki, D H; He, S; Rodig, S; Look, A T

    2017-02-23

    Malignant peripheral nerve sheath tumors (MPNSTs) are aggressive, frequently metastatic sarcomas that are associated with neurofibromatosis type 1 (NF1), a prominent inherited genetic disease in humans. Although loss of the NF1 gene predisposes to MPNST induction, relatively long tumor latency in NF1 patients suggests that additional genetic or epigenetic abnormalities are needed for the development of these nerve sheath malignancies. To study the molecular pathways contributing to the formation of MPNSTs in NF1 patients, we used a zebrafish tumor model defined by nf1 loss in a p53-deficient background together with the overexpression of either wild-type or constitutively activated PDGFRA (platelet-derived growth factor receptor-α) under control of the sox10 neural crest-specific promoter. Here we demonstrate the accelerated onset and increased penetrance of MPNST formation in fish overexpressing both the wild-type and the mutant PDGFRA transgenes in cells of neural crest origin. Interestingly, overexpression of the wild-type PDGFRA was even more potent in promoting transformation than the mutant PDGFRA, which is important because ~78% of human MPNSTs have expression of wild-type PDGFRA, whereas only 5% harbor activating mutations of the gene encoding this receptor. Further analysis revealed the induction of cellular senescence in zebrafish embryos overexpressing mutant, but not wild-type, PDGFRA, suggesting a mechanism through which the oncogenic activity of the mutant receptor is tempered by the activation of premature cellular senescence in an NF1-deficient background. Taken together, our study suggests a model in which overexpression of wild-type PDGFRA associated with NF1 deficiency leads to aberrant activation of downstream RAS signaling and thus contributes importantly to MPNST development-a prediction supported by the ability of the kinase inhibitor sunitinib alone and in combination with the MEK inhibitor trametinib to retard MPNST progression in

  5. Overexpression of PDGFRA cooperates with loss of NF1 and p53 to accelerate the molecular pathogenesis of malignant peripheral nerve sheath tumors

    PubMed Central

    Ki, D H; He, S; Rodig, S; Look, A T

    2017-01-01

    Malignant peripheral nerve sheath tumors (MPNSTs) are aggressive, frequently metastatic sarcomas that are associated with neurofibromatosis type 1 (NF1), a prominent inherited genetic disease in humans. Although loss of the NF1 gene predisposes to MPNST induction, relatively long tumor latency in NF1 patients suggests that additional genetic or epigenetic abnormalities are needed for the development of these nerve sheath malignancies. To study the molecular pathways contributing to the formation of MPNSTs in NF1 patients, we used a zebrafish tumor model defined by nf1 loss in a p53-deficient background together with the overexpression of either wild-type or constitutively activated PDGFRA (platelet-derived growth factor receptor-α) under control of the sox10 neural crest-specific promoter. Here we demonstrate the accelerated onset and increased penetrance of MPNST formation in fish overexpressing both the wild-type and the mutant PDGFRA transgenes in cells of neural crest origin. Interestingly, overexpression of the wild-type PDGFRA was even more potent in promoting transformation than the mutant PDGFRA, which is important because ~78% of human MPNSTs have expression of wild-type PDGFRA, whereas only 5% harbor activating mutations of the gene encoding this receptor. Further analysis revealed the induction of cellular senescence in zebrafish embryos overexpressing mutant, but not wild-type, PDGFRA, suggesting a mechanism through which the oncogenic activity of the mutant receptor is tempered by the activation of premature cellular senescence in an NF1-deficient background. Taken together, our study suggests a model in which overexpression of wild-type PDGFRA associated with NF1 deficiency leads to aberrant activation of downstream RAS signaling and thus contributes importantly to MPNST development—a prediction supported by the ability of the kinase inhibitor sunitinib alone and in combination with the MEK inhibitor trametinib to retard MPNST progression in

  6. Outcome comparison of endoscopic and transpalpebral decompression for treatment of frontal migraine headaches.

    PubMed

    Liu, Mengyuan T; Chim, Harvey; Guyuron, Bahman

    2012-05-01

    This study was designed to compare the efficacy of the transpalpebral versus endoscopic approach to decompression of the supraorbital and supratrochlear nerves in patients with frontal migraine headaches. The medical charts of 253 patients who underwent surgery for frontal migraine headaches were reviewed. These patients underwent either transpalpebral nerve decompression (n = 62) or endoscopic nerve decompression (n = 191). Preoperative and 12-month or greater postoperative migraine frequency, duration, and intensity were analyzed to determine the success of the surgeries. Forty-nine of 62 patients (79 percent) in the transpalpebral nerve decompression group and 170 of 191 patients (89 percent) who underwent endoscopic nerve decompression experienced a successful outcome (at least a 50 percent decrease in migraine frequency, duration, or intensity) after 1 year from surgery. Endoscopic nerve decompression had a significantly higher success rate than transpalpebral nerve decompression (p < 0.05). Thirty-two patients (52 percent) in the transpalpebral nerve decompression group and 128 patients (67 percent) who underwent endoscopic nerve decompression observed elimination of migraine headaches. The elimination rate was significantly higher in the endoscopic nerve decompression group than in the transpalpebral nerve decompression group (p < 0.03). Endoscopic nerve decompression was found to be more successful at reducing or eliminating frontal migraine headaches than transpalpebral nerve decompression and should be selected as the first choice whenever it is anatomically feasible. Therapeutic, III.

  7. CT, MRI, and (18)F-FDG PET/CT findings of malignant peripheral nerve sheath tumor of the head and neck.

    PubMed

    Kim, Ha Youn; Hwang, Ji Young; Kim, Hyung-Jin; Kim, Yi Kyung; Cha, Jihoon; Park, Gyeong Min; Kim, Sung Tae

    2017-10-01

    Background Malignant peripheral nerve sheath tumor (MPNST) is a highly malignant tumor and rarely occurs in the head and neck. Purpose To describe the imaging features of MPNST of the head and neck. Material and Methods We retrospectively analyzed computed tomography (CT; n = 14), magnetic resonance imaging (MRI; n = 16), and (18)F-FDG PET/CT (n = 5) imaging features of 18 MPNSTs of the head and neck in 17 patients. Special attention was paid to determine the nerve of origin from which the tumor might have arisen. Results All lesions were well-defined (n = 3) or ill-defined (n = 15) masses (mean, 6.1 cm). Lesions were at various locations but most commonly the neck (n = 8), followed by the intracranial cavity (n = 3), paranasal sinus (n = 2), and orbit (n = 2). The nerve of origin was inferred for 11 lesions: seven in the neck, two in the orbit, one in the cerebellopontine angle, and one on the parietal scalp. Attenuation, signal intensity, and enhancement pattern of the lesions on CT and MRI were non-specific. Necrosis/hemorrhage/cystic change within the lesion was considered to be present on images in 13 and bone change in nine. On (18)F-FDG PET/CT images, all five lesions demonstrated various hypermetabolic foci with maximum standard uptake value (SUVmax) from 3.2 to 14.6 (mean, 7.16 ± 4.57). Conclusion MPNSTs can arise from various locations in the head and neck. Though non-specific, a mass with an ill-defined margin along the presumed course of the cranial nerves may aid the diagnosis of MPSNT in the head and neck.

  8. Spatially- and temporally-controlled postnatal p53 knockdown cooperates with embryonic Schwann cell precursor Nf1 gene loss to promote malignant peripheral nerve sheath tumor formation.

    PubMed

    Hirbe, Angela C; Dahiya, Sonika; Friedmann-Morvinski, Dinorah; Verma, Inder M; Clapp, D Wade; Gutmann, David H

    2016-02-16

    Malignant peripheral nerve sheath tumors (MPNSTs) are highly aggressive sarcomas that arise sporadically or in association with the Neurofibromatosis type 1 (NF1) cancer predisposition syndrome. In individuals with NF1, MPNSTs are hypothesized to arise from Nf1-deficient Schwann cell precursor cells following the somatic acquisition of secondary cooperating genetic mutations (e.g., p53 loss). To model this sequential genetic cooperativity, we coupled somatic lentivirus-mediated p53 knockdown in the adult right sciatic nerve with embryonic Schwann cell precursor Nf1 gene inactivation in two different Nf1 conditional knockout mouse strains. Using this approach, ~60% of mice with Periostin-Cre-mediated Nf1 gene inactivation (Periostin-Cre; Nf1(flox/flox) mice) developed tumors classified as low-grade MPNSTs following p53 knockdown (mean, 6 months). Similarly, ~70% of Nf1+/- mice with GFAP-Cre-mediated Nf1 gene inactivation (GFAP-Cre; Nf1(flox/null) mice) developed low-grade MPNSTs following p53 knockdown (mean, 3 months). In addition, wild-type and Nf1+/- mice with GFAP-Cre-mediated Nf1 loss develop MPNSTs following somatic p53 knockout with different latencies, suggesting potential influences of Nf1+/- stromal cells in MPNST pathogenesis. Collectively, this new MPNST model system permits the analysis of somatically-acquired events as well as tumor microenvironment signals that potentially cooperate with Nf1 loss in the development and progression of this deadly malignancy.

  9. Convection-Enhanced Delivery (CED) in an Animal Model of Malignant Peripheral Nerve Sheath Tumors and Plexiform Neurofibromas

    DTIC Science & Technology

    2011-09-01

    povidone-iodine swabs or gauzes. 70% alcohol swab or gauze is used to remove the remaining povidone-iodine from the skin. ~100μL 1% lidocaine is...site. A few drops of lidocaine are dropped on the nerve. A 34 Gauge fused silica (WPI) cannula is inserted at a sharp angle (~10°) along the nerve...remove the remaining povidone-iodine from the skin. ~100μL 1% lidocaine is injected along the incision line to ensure adequate analgesia. A 15mm dorsal

  10. Does the presence of the nerve root sedimentation sign on MRI correlate with the operative level in patients undergoing posterior lumbar decompression for lumbar stenosis?

    PubMed

    Fazal, Akil; Yoo, Andrew; Bendo, John A

    2013-08-01

    Recent research describes the use of a nerve root sedimentation sign to diagnose lumbar spinal stenosis (LSS). The lack of sedimentation of the nerve roots (positive sedimentation sign) to the dorsal part of the dural sac is the characteristic feature of this new radiological parameter. To demonstrate how the nerve root sedimentation sign compares with other more traditional radiological parameters in patients who have been operated for LSS. A retrospective chart and image review. Preoperative magnetic resonance images (MRIs) were reviewed from 71 consecutive operative patients who presented with LSS and received spinal decompression surgery from 2006 to 2010. Preoperative T2-weighted MRIs were reviewed for each patient. One hundred thirty-four vertebral levels from L1 to L5 were measured for: sedimentation sign, cross-sectional area (CSA) and anterior/posterior (A/P) diameter of the dural sac, thickness of the ligamentum flavum, and Fujiwara grade of facet hypertrophy. Radiological measurements were made using Surgimap 1.1.2.169 software (Nemaris, Inc., New York, NY, USA). Statistical analyses were performed using the SPSS 17.0 statistical software (SPSS Inc., Chicago, IL, USA). Significance was demonstrated using unpaired t tests and chi-squared tests. Study funding was departmental. There were no study-specific conflicts of interest-associated biases. A positive sedimentation sign was determined in 120 operated levels (89.5%), whereas 14 levels (10.5%) had no sign (negative sedimentation sign). The mean CSA and A/P diameter were 140.62 mm(2) (standard deviation [SD]=53) and 11.76 mm (SD=3), respectively, for the no-sign group; the mean CSA and A/P diameter were 81.87 mm(2) (SD=35) and 8.76 mm (SD=2.2), respectively, for the sedimentation sign group (p<.001). We found that 60% of levels with Fujiwara Grade A facet hypertrophy did not have a sedimentation sign, whereas 86.3% of levels with Grade B, 93.2% of levels with Grade C, and 100.0% of levels with Grade D

  11. Sacrotuberous Ligament Healing following Surgical Division during Transgluteal Pudendal Nerve Decompression: A 3-Tesla MR Neurography Study

    PubMed Central

    Fritz, Jan; Fritz, Benjamin; Dellon, A. Lee

    2016-01-01

    Pelvic pain due to chronic pudendal nerve (PN) compression, when treated surgically, is approached with a transgluteal division of the sacrotuberous ligament (STL). Controversy exists as to whether the STL heals spontaneously or requires grafting. Therefore, the aim of this study was to determine how surgically divided and unrepaired STL heal. A retrospective evaluation of 10 patients who had high spatial resolution 3-Tesla magnetic resonance imaging (3T MRI) exams of the pelvis was done using an IRB-approved protocol. Each patient was referred for residual pelvic pain after a transgluteal STL division for chronic pudendal nerve pain. Of the 10 patients, 8 had the STL divided and not repaired, while 2 had the STL divided and reconstructed with an allograft tendon. Of the 8 that were left unrepaired, 6 had bilateral surgery. Outcome variables included STL integrity and thickness. Normative data for the STL were obtained through a control group of 20 subjects. STL integrity and thickness were measured directly on 3 T MR Neurography images, by two independent Radiologists. The integrity and thickness of the post-surgical STL was evaluated 39 months (range, 9–55) after surgery. Comparison was made with the native contra-lateral STL in those who had unilateral STL division, and with normal, non-divided STL of subjects of the control group. The normal STL measured 3 mm (minimum and maximum of absolute STL thickness, 2–3 mm). All post-operative STL were found to be continuous regardless of the surgical technique used. Measured at level of Alcock’s canal in the same plane as the obturator internus tendon posterior to the ischium, the mean anteroposterior STL diameter was 5 mm (range, 4–5 mm) in the group of prior STL division without repair and 8 mm (range, 8–9 mm) in the group with the STL reconstructed with grafts (p<0.05). The group of healed STLs were significantly thicker than the normal STL (p<0.05). We conclude that a surgically divided STL will heal

  12. Fractionated Conformal Radiotherapy for Management of Optic Nerve Sheath Meningiomas: Long-Term Outcomes of Tumor Control and Visual Function at a Single Institution

    SciTech Connect

    Metellus, Philippe; Kapoor, Sumit; Kharkar, Siddharth; Batra, Sachin; Jackson, Juan F.; Kleinberg, Lawrence; Miller, Neil R.; Rigamonti, Daniele

    2011-05-01

    Purpose: To provide the long-term outcomes of patients treated with fractionated conformal radiotherapy (FCRT) for presumed optic nerve sheath meningiomas (ONSMs). Patients and Methods: Between 1995 and 2002, 9 patients with a presumed ONSM were treated with FCRT at our institution. The indications for FCRT were significant visual dysfunction at presentation, progression of visual dysfunction during a period of observation, tumor growth documented by sequential imaging, or a combination of these findings. In 2 patients, FCRT was performed as adjuvant therapy, and in 7, it was the initial and primary treatment. Results: Of the 9 patients, 6 were women and 3 were men, with a mean age of 47 years. All 9 patients had evidence of optic nerve dysfunction in the affected eye, characterized by reduced visual acuity, a visual field defect, and a relative afferent pupillary defect. In addition, 2 patients had proptosis and 1 had diplopia. The mean follow-up period was 98 {+-} 31.7 months (median, 90; range, 61-151). After FCRT, the visual function improved in the 7 patients who had undergone FCRT as the primary treatment. However, 2 patients who were blind in their affected eye at FCRT remained blind. In 4 of the 7 patients with improvement, the improvement was documented within 1-3 months after FCRT. The tumor control rate was 100%. Proptosis and diplopia also regressed in 100% of patients. At 2 years after FCRT, 1 patient had developed radiation retinopathy. Conclusion: The results of our study have shown that FCRT is a safe and effective treatment of ONSMs, affording satisfactory long-term tumor control, good functional outcome, and low treatment morbidity. FCRT should be considered the treatment of choice for patients with presumed ONSMs for whom the treatment has been deemed appropriate.

  13. EZH2-miR-30d-KPNB1 pathway regulates malignant peripheral nerve sheath tumour cell survival and tumourigenesis.

    PubMed

    Zhang, Pingyu; Garnett, Jeannine; Creighton, Chad J; Al Sannaa, Ghadah Abbas; Igram, Davis R; Lazar, Alexander; Liu, Xiuping; Liu, Changgong; Pollock, Raphael E

    2014-02-01

    Malignant peripheral nerve sheath tumours (MPNSTs), which develop sporadically or from neurofibromatosis, recur frequently with high metastatic potential and poor outcome. The polycomb group protein enhancer of zeste homologue 2 (EZH2) is an important regulator for various human malignancies. However, the function of EZH2 in MPNSTs is unknown. Here we report that the EZH2-miR-30d-KPNB1 signalling pathway is critical for MPNST tumour cell survival in vitro and tumourigenicity in vivo. Up-regulated EZH2 in MPNST inhibits miR-30d transcription via promoter binding activity, leading to enhanced expression of the nuclear transport receptor KPNB1 that is inhibited by miR-30d targeting of KPNB1 3' UTR region. Furthermore, inhibition of EZH2 or KPNB1, or miR-30d over-expression, induces MPNST cell apoptosis in vitro and suppresses tumourigenesis in vivo. More importantly, forced over-expression of KPNB1 rescues MPNST cell apoptosis induced by EZH2 knockdown. Immunohistochemical analyses show that EZH2 and KPNB1 over-expression is observed in human MPNST specimens and is negatively associated with miR-30d expression. Our findings identify a novel signalling pathway involved in MPNST tumourigenesis, and also suggest that EZH2-miR-30d-KPNB1 signalling represents multiple potential therapeutic targetable nodes for MPNST.

  14. TERT promoter mutations and BRAF mutations are rare in sporadic, and TERT promoter mutations are absent in NF1-related malignant peripheral nerve sheath tumors.

    PubMed

    Dubbink, Hendrikus J; Bakels, Hannah; Post, Edward; Zwarthoff, Ellen C; Verdijk, Robert M

    2014-11-01

    Hot spot mutations in the promoter region of telomerase reverse transcriptase (TERT promoter mutations) occur frequently in tumors of neuroectodermal origin such as melanoma and glioma. Many of these tumors are of neuroectodermal or ectomesenchymal origin which is suggestive of TERT promoter mutations playing a role in the development of malignant peripheral nerve sheath tumors (MPNSTs). In melanoma a correlation has been suggested between the occurrence of TERT promoter mutations and v-RAF murine sarcoma viral oncogene homolog B1 (BRAF) mutations. We investigated TERT promoter and BRAF mutation frequency in respectively 94 and 86 consecutive MPNST cases from our institute. TERT promoter mutation analysis on DNA from formalin-fixed, paraffin-embedded specimens was performed by SNaPshot analysis. Sequence analysis of BRAF was performed by bidirectional DNA sequencing. We identified TERT C228T or C250T promoter mutations in 10 % (9/94) and BRAF V600E mutations in 3 % (3/86) of MPNSTs. All TERT promoter- and BRAF mutations occurred in NF1 unrelated tumors. One co-occurrence of a TERT promoter- and a BRAF mutation was observed. In comparison with other neuroectodermal derived malignant neoplasms, TERT promoter mutations occur at relatively low frequency in MPNSTs. The observation of TERT promotor and BRAF mutations in sporadic MPNSTs and the absence of TERT promotor and rarity of BRAF mutations in NF1 related tumors may imply an alternative genetic route of tumor progression in both patient groups.

  15. Peripheral nerve sheath tumors of the gastrointestinal tract: a multicenter study of 58 patients including NF1-associated gastric schwannoma and unusual morphologic variants.

    PubMed

    Agaimy, Abbas; Märkl, Bruno; Kitz, Julia; Wünsch, Peter H; Arnholdt, Hans; Füzesi, Laszlo; Hartmann, Arndt; Chetty, Runjan

    2010-04-01

    The frequency and morphological spectrum of gastrointestinal peripheral nerve sheath tumors (PNSTs) from consecutive case material has not been studied in the c-KIT era. We reviewed all mesenchymal gastrointestinal (GI) lesions at our departments according to current diagnostic criteria. PNSTs formed the third commonest group of mesenchymal GI tumors with a lower frequency (< or =5%) compared to gastrointestinal stromal tumors (GISTs; approximately 50%) and smooth muscle neoplasms ( approximately 30%). Granular cell tumors (GCTs; n = 31) and schwannomas (n = 22) were the most common types of PNSTs encountered. Rare tumors included neurofibromatosis 1 (NF1)-associated PNSTs (n = 5) and gastric perineurioma (n = 1). Thirteen schwannomas (including also some recent cases) were initially diagnosed as GIST, leiomyoma, or neurofibroma. Unusual histological variants included sigmoid GCT with prominent lipomatous component (n = 1), reticular-microcystic schwannoma of small (n = 1) and large (n = 1) bowel, NF1-associated gastric schwannoma (the first case to date), and psammomatous melanotic colonic schwannoma unrelated to Carney complex (n = 1). PNSTs coexisted with GIST in four patients (three had definite NF1). In conclusion, PNSTs of the GI tract are rare uniformly benign neoplasms that may show schwannian, perineurial, fibroblastic, or mixed differentiation. Most of them (92%) occurred sporadically unassociated with NF1 or NF2. Gastrointestinal PNSTs are still underrecognized by general pathologists. Awareness of their diverse morphology will help to avoid confusing them with smooth muscle neoplasms and GIST that they may closely mimic.

  16. Discovery of a small molecule targeting IRA2 deletion in budding yeast and neurofibromin loss in malignant peripheral nerve sheath tumor cells

    PubMed Central

    Wood, Matthew; Rawe, Melissa; Johansson, Gunnar; Pang, Shu; Soderquist, Ryan S.; Patel, Ami V.; Nelson, Sandra; Seibel, William; Ratner, Nancy; Sanchez, Yolanda

    2011-01-01

    Malignant peripheral nerve sheath tumor (MPNST) is a life-threatening complication of neurofibromatosis type 1 (NF1). NF1 is caused by mutation in the gene encoding neurofibromin, a negative regulator of Ras signaling. There are no effective pharmacologic therapies for MPNST. To identify new therapeutic approaches targeting this dangerous malignancy, we developed assays in NF1+/+ and NF1−/ − MPNST cell lines and in budding yeast lacking the NF1 homologue IRA2 (ira2Δ). Here we describe UC1, a small molecule that targets NF1−/− cell lines and ira2Δ budding yeast. Using yeast genetics we identified NAB3 as a high-copy suppressor of UC1 sensitivity. NAB3 encodes an RNA binding protein that associates with the C-terminal domain of RNA Pol II and plays a role in the termination of non-polyadenylated RNA transcripts. Strains with deletion of IRA2 are sensitive to genetic inactivation of NAB3, suggesting an interaction between Ras signaling and Nab3-dependent transcript termination. This work identifies a lead compound and a possible target pathway for NF1-associated MPNST, and demonstrates a novel model system approach to identify and validate target pathways for cancer cells in which NF1 loss drives tumor formation. PMID:21697395

  17. The Challenge of Cancer Genomics in Rare Nervous System Neoplasms: Malignant Peripheral Nerve Sheath Tumors as a Paradigm for Cross-Species Comparative Oncogenomics.

    PubMed

    Carroll, Steven L

    2016-03-01

    Comprehensive genomic analyses of common nervous system cancers provide new insights into their pathogenesis, diagnosis, and treatment. Although analogous studies of rare nervous system tumors are needed, there are major barriers to performing such studies. Cross-species comparative oncogenomics, identifying driver mutations in mouse cancer models and validating them in human tumors, is a promising alternative. Although still in its infancy, this approach is being applied to malignant peripheral nerve sheath tumors (MPNSTs), rare Schwann cell-derived malignancies that occur sporadically, after radiotherapy, and in neurofibromatosis type 1. Studies of human neurofibromatosis type 1-associated tumors suggest that NF1 tumor suppressor loss in Schwann cells triggers cell-autonomous and intercellular changes, resulting in development of benign neurofibromas; subsequent neurofibroma-MPNST progression is caused by aberrant growth factor signaling and mutations affecting the p16(INK4A)-cyclin D1-CDK4-Rb and p19(ARF)-Mdm2-p53 cell cycle pathways. Mice with Nf1, Trp53, and/or Cdkn2a mutations that overexpress the Schwann cell mitogen neuregulin-1 or overexpress the epidermal growth factor receptor validate observations in human tumors and, to various degrees, model human tumorigenesis. Genomic analyses of MPNSTs arising in neuregulin-1 and epidermal growth factor receptor-overexpressing mice and forward genetic screens with Sleeping Beauty transposons implicate additional signaling cascades in MPNST pathogenesis. These studies confirm the utility of mouse models for MPNST driver gene discovery and provide new insights into the complexity of MPNST pathogenesis.

  18. A novel NF1 mutation in a Chinese patient with giant café-au-lait macule in neurofibromatosis type 1 associated with a malignant peripheral nerve sheath tumor and bone abnormality.

    PubMed

    Tong, H-X; Li, M; Zhang, Y; Zhu, J; Lu, W-Q

    2012-08-29

    Neurofibromatosis type 1 (NF1; OMIM#162200) is a common neurocutaneous disorder that is characterized by multiple café-au-lait, skinfold freckling, Lisch nodules, and neurofibromas. Mutations in the NF1 gene, which encodes the neurofibromin protein, have been identified as the pathogenic gene of NF1. In this study, we present a clinical and molecular study of a Chinese patient with giant café-au-lait in NF1. The patient showed >6 café-au-lait spots on the body, axillary freckling, and multiple subcutaneous neurofibromas. He also had a malignant peripheral nerve sheath tumor and bone abnormalities. The germline mutational analysis of the NF1 gene revealed a novel missense mutation in exon 13. It is a novel heterozygous nucleotide G>A transition at position 2241 of the NF1 gene. We found no mutation in malignant peripheral nerve sheath tumor DNA from this patient. This expands the database for NF1 gene mutations in NF1. Its absence in the normal chromosomes suggests that it is responsible for the NF1 phenotype. To our knowledge, this is the first case of giant café-au-lait macule in NF1 associated with a malignant peripheral nerve sheath tumor and bone abnormality.

  19. Clinical efficacy of simple decompression versus anterior transposition of the ulnar nerve for the treatment of cubital tunnel syndrome: A meta-analysis.

    PubMed

    Chen, Hong-wei; Ou, Shan; Liu, Guo-dong; Fei, Jun; Zhao, Gang-sheng; Wu, Li-jun; Pan, Jun

    2014-11-01

    The aim of this study was to evaluate the clinical efficacy of simple decompression (SD) versus anterior transposition (AT) of the ulnar nerve for the treatment of cubital tunnel syndrome. Seven public databases (PubMed, MEDLINE and EMBASE, Springer, Elsevier Science Direct, Cochrane Library and Google scholar) were searched from 1971 to December 2013. The overall odds ratios (OR) and their 95% confidence intervals (CI) were pooled to compare the clinical outcomes. Subgroup analysis was performed based on the region, study type, Jadad score, type of AT, and follow-up duration. Meta-analysis was conducted by using Rev. Man 5.1 and Stata 11.0 software. Finally, we included 13 studies involved 1009 (500 patients receiving SD and 509 patients receiving AT) patients with cubital tunnel syndrome. The overall estimate (OR=0.91, 95% CI=0.67-1.23, P=0.536) indicated that there was no significantly statistical difference between the clinical outcomes of patients treated with SD and AT. Meanwhile, subgroup analyses by region, study type, Jadad score, type of AT and follow-up duration showed the consistent results with the overall estimate. In addition, we found that the incidence of complications in patients treated by SD was significantly lower than that in patients treated by AT (OR=0.32, 95% CI=0.17-0.60, P=0.05). In conclusion, although SD had equivalent clinical outcomes with AT for the treatment of cubital tunnel syndrome, SD should be preferred due to having lower incidence of complications. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. TAGLN expression is upregulated in NF1-associated malignant peripheral nerve sheath tumors by hypomethylation in its promoter and subpromoter regions.

    PubMed

    Park, Gun-Hoo; Lee, Su-Jin; Yim, Hyunee; Han, Jae-Ho; Kim, Hyon J; Sohn, Young-Bae; Ko, Jung Min; Jeong, Seon-Yong

    2014-10-01

    Neurofibromatosis type 1 (NF1) caused by NF1 gene mutation is a commonly inherited autosomal dominant disorder. Malignant peripheral nerve sheath tumors (MPNSTs), a type of aggressive sarcoma, are a major cause of mortality in NF1 patients. The malignant transformation of benign plexiform neurofibromas (PNs) to MPNSTs is a marked peculiarity in NF1 patients, yet the pathogenesis remains poorly understood. We found that an actin-associated protein transgelin (SM22) was highly expressed in NF1-deficient MPNST tissues compared to NF1-deficient PN tissues using immunohistological staining and primary cultured MPNST cells in western blot analysis. We further found that this transgelin upregulation was caused by increased transcriptional expression of the TAGLN gene encoding transgelin. Comparison of DNA methylation values in the promoter and subpromoter regions of the TAGLN gene in three types of NF1-deficient primary-cultured cells, derived from an NF1 patient's normal phenotype, a benign PN and MPNST tissues, revealed that the TAGLN gene was hypomethylated in the MPNST cells. Next, to determine the functional role of transgelin in MPNST pathogenesis, we manipulated the TAGLN gene expression and investigated the alteration of the RAS-mitogen-activated protein kinase (MAPK) signaling pathway in the normal-phenotypic and malignant tumor cells. The downregulation of TAGLN expression in NF1-deficient MPNST tumor cells through the treatment of the small interfering RNA resulted in a decrease in the RAS activation (GTP-RAS) and the downstream ERK1/2 activation (phosphorylated ERK1/2), while the overexpression of TAGLN in normal-phenotypic NF1-deficient cells caused an increase in RAS and ERK1/2 activation. These results indicate that upregulation of transgelin caused by hypomethylation of the TAGLN gene is closely involved in tumor progression in NF1.

  1. Protein expression of BIRC5, TK1, and TOP2A in malignant peripheral nerve sheath tumours--A prognostic test after surgical resection.

    PubMed

    Kolberg, Matthias; Høland, Maren; Lind, Guro E; Ågesen, Trude H; Skotheim, Rolf I; Hall, Kirsten Sundby; Mandahl, Nils; Smeland, Sigbjørn; Mertens, Fredrik; Davidson, Ben; Lothe, Ragnhild A

    2015-06-01

    No consensus treatment regime exists beyond surgery for malignant peripheral nerve sheath tumours (MPNST), and the purpose of the present study was to find new approaches to stratify patients with good and poor prognosis and to better guide therapeutic intervention for this aggressive soft tissue cancer. From a total of 67 MPNSTs from Scandinavian patients with and without neurofibromatosis type 1, 30 MPNSTs were investigated by genome-wide RNA expression profiling and 63 MPNSTs by immunohistochemical (IHC) analysis, and selected genes were submitted to analyses of disease-specific survival. The potential drug target genes survivin (BIRC5), thymidine kinase 1 (TK1), and topoisomerase 2-alpha (TOP2A), all encoded on chromosome arm 17q, were up-regulated in MPNST as compared to benign neurofibromas. Each of them was found to be independent prognostic markers on the gene expression level, as well as on the protein level. A prognostic profile was identified by combining the nuclear expression scores of the three proteins. For patients with completely resected tumours only 15% in the high risk group were alive after two years, as compared to 78% in the low risk group. In conclusion, we found a novel protein expression profile which identifies MPNST patients with inferior prognosis even after assumed curative surgery. The tested proteins are drug targets; therefore the expression profile may provide predictive information guiding the design of future clinical trials. Importantly, as the effect is seen on the protein level using IHC, the biomarker panel can be readily implemented in routine clinical testing.

  2. Individual patient data systematic review and meta-analysis of optic nerve sheath diameter ultrasonography for detecting raised intracranial pressure: protocol of the ONSD research group.

    PubMed

    Dubourg, Julie; Messerer, Mahmoud; Karakitsos, Dimitrios; Rajajee, Venkatakrishna; Antonsen, Erik; Javouhey, Etienne; Cammarata, Alessandro; Cotton, Michael; Daniel, Roy Thomas; Denaro, Carmelo; Douzinas, Emmanuel; Dubost, Clément; Berhouma, Moncef; Kassai, Behrouz; Rabilloud, Muriel; Gullo, Antonino; Hamlat, Abderrhammane; Kouraklis, Gregorios; Mannanici, Giuseppe; Marill, Keith; Merceron, Sybille; Poularas, John; Ristagno, Giuseppe; Noble, Vicki; Shah, Sachita; Kimberly, Heidi; Cammarata, Gianluca; Moretti, Riccardo; Geeraerts, Thomas

    2013-08-06

    The purpose of the optic nerve sheath diameter (ONSD) research group project is to establish an individual patient-level database from high quality studies of ONSD ultrasonography for the detection of raised intracranial pressure (ICP), and to perform a systematic review and an individual patient data meta-analysis (IPDMA), which will provide a cutoff value to help physicians making decisions and encourage further research. Previous meta-analyses were able to assess the diagnostic accuracy of ONSD ultrasonography in detecting raised ICP but failed to determine a precise cutoff value. Thus, the ONSD research group was founded to synthesize data from several recent studies on the subject and to provide evidence on the diagnostic accuracy of ONSD ultrasonography in detecting raised ICP. This IPDMA will be conducted in different phases. First, we will systematically search for eligible studies. To be eligible, studies must have compared ONSD ultrasonography to invasive intracranial devices, the current reference standard for diagnosing raised ICP. Subsequently, we will assess the quality of studies included based on the QUADAS-2 tool, and then collect and validate individual patient data. The objectives of the primary analyses will be to assess the diagnostic accuracy of ONSD ultrasonography and to determine a precise cutoff value for detecting raised ICP. Secondly, we will construct a logistic regression model to assess whether patient and study characteristics influence diagnostic accuracy. We believe that this IPD MA will provide the most reliable basis for the assessment of diagnostic accuracy of ONSD ultrasonography for detecting raised ICP and to provide a cutoff value. We also hope that the creation of the ONSD research group will encourage further study. PROSPERO registration number: CRD42012003072.

  3. Individual patient data systematic review and meta-analysis of optic nerve sheath diameter ultrasonography for detecting raised intracranial pressure: protocol of the ONSD research group

    PubMed Central

    2013-01-01

    Background The purpose of the optic nerve sheath diameter (ONSD) research group project is to establish an individual patient-level database from high quality studies of ONSD ultrasonography for the detection of raised intracranial pressure (ICP), and to perform a systematic review and an individual patient data meta-analysis (IPDMA), which will provide a cutoff value to help physicians making decisions and encourage further research. Previous meta-analyses were able to assess the diagnostic accuracy of ONSD ultrasonography in detecting raised ICP but failed to determine a precise cutoff value. Thus, the ONSD research group was founded to synthesize data from several recent studies on the subject and to provide evidence on the diagnostic accuracy of ONSD ultrasonography in detecting raised ICP. Methods This IPDMA will be conducted in different phases. First, we will systematically search for eligible studies. To be eligible, studies must have compared ONSD ultrasonography to invasive intracranial devices, the current reference standard for diagnosing raised ICP. Subsequently, we will assess the quality of studies included based on the QUADAS-2 tool, and then collect and validate individual patient data. The objectives of the primary analyses will be to assess the diagnostic accuracy of ONSD ultrasonography and to determine a precise cutoff value for detecting raised ICP. Secondly, we will construct a logistic regression model to assess whether patient and study characteristics influence diagnostic accuracy. Discussion We believe that this IPD MA will provide the most reliable basis for the assessment of diagnostic accuracy of ONSD ultrasonography for detecting raised ICP and to provide a cutoff value. We also hope that the creation of the ONSD research group will encourage further study. Trial registration PROSPERO registration number: CRD42012003072 PMID:23919384

  4. Genomic and Molecular Characterization of Malignant Peripheral Nerve Sheath Tumor Identifies the IGF1R Pathway as a Primary Target for Treatment

    PubMed Central

    Yang, Jilong; Ylipää, Antti; Sun, Yan; Zheng, Hong; Chen, Kexin; Nykter, Matti; Trent, Jonathan; Ratner, Nancy; Lev, Dina C.; Zhang, Wei

    2011-01-01

    Purpose Malignant peripheral nerve sheath tumor (MPNST) is a rare sarcoma that lacks effective therapeutic strategies. We gain insight into the most recurrent genetically altered pathways with the purpose of scanning possible therapeutic targets. Experimental design We performed a microarray based-comparative genomic hybridization (aCGH) profiling of two cohorts of primary MPNST tissue samples including 25 patients treated at The University of Texas MD Anderson Cancer Center and 26 patients from Tianjin Cancer Hospital. IHC and cell biology detection and validation were performed on human MPNST tissues and cell lines. Results Genomic characterization of 51 MPNST tissue samples identified several frequently amplified regions harboring 2,599 genes and regions of deletion including 4,901 genes. At the pathway level, we identified a significant enrichment of copy number–altering events in the insulin-like growth factor 1 receptor (IGF1R) pathway, including frequent amplifications of the IGF1R gene itself. To validate the IGF1R pathway as a potential target in MPNSTs, we first confirmed that high IGF1R protein correlated with worse tumor-free survival in an independent set of samples using immunohistochemistry. Two MPNST cell lines (ST88-14 and STS26T) were used to determine the effect of attenuating IGF1R. Inhibition of IGF1R in ST88-14 cells using small interfering RNAs or an IGF1R inhibitor, MK-0646, led to significant decreases in cell proliferation, invasion, and migration accompanied by attenuation of the PI3K/AKT and MAPK pathways. Conclusion These integrated genomic and molecular studies provide evidence that the IGF1R pathway is a potential therapeutic target for patients with MPNST. PMID:22042973

  5. Targeting the PI3K/mTOR axis, alone and in combination with autophagy blockade, for the treatment of malignant peripheral nerve sheath tumors

    PubMed Central

    Ghadimi, Markus P; Lopez, Gonzalo; Torres, Keila E.; Belousov, Roman; Young, Eric D.; Liu, Jeffery; Brewer, Kari J.; Hoffman, Aviad; Lusby, Kristelle; Lazar, Alexander J; Pollock, Raphael E.; Lev, Dina

    2012-01-01

    There is a critical need for efficacious therapeutic strategies to improve the outcome of patients afflicted by malignant peripheral nerve sheath tumors (MPNST). Multiple lines of evidence suggest a role for deregulated PI3K/mTOR signaling in MPNST, making this axis an attractive target for therapeutic manipulation. Based on previous observations obtained from in vitro experimentation, here we aimed to assess the effects of PI3K/mTOR blockade on MPNST growth in vivo. The anti-MPNST impact of XL765, a dual PI3K/mTOR inhibitor currently being evaluated in human cancer clinical trials, was tested in two human MPNST xenograft models (STS26T and MPNST724) and an experimental model of pulmonary metastasis (STS26T). XL765 abrogated human MPNST local and metastatic growth in SCID mice. Notably, this therapeutic approach failed to induce apoptosis in MPNST cells but rather resulted in marked productive autophagy. Importantly, genetic and pharmacologic autophagy blockade reversed apoptotic resistance and resulted in significant PI3K/mTOR inhibition-induced MPNST cell death. The addition of the autophagy inhibitor, chloroquine, to the therapeutic regimen of MPNST xenografts after pre-treatment with XL765 resulted in superior anti-tumor effects as compared to either agent alone. Together, pre-clinical studies described here expand our previous findings and suggest that PI3K/mTOR inhibition alone and (most importantly) in combination with autophagy blockade may comprise a novel and efficacious therapy for patients harboring MPNST. PMID:22848094

  6. The role of angiogenesis in the transformation of plexiform neurofibroma into malignant peripheral nerve sheath tumors in children with neurofibromatosis type 1.

    PubMed

    Gesundheit, Benjamin; Parkin, Patricia; Greenberg, Mark; Baruchel, Sylvain; Senger, Christof; Kapelushnik, Josef; Smith, Charles; Klement, Giannoula Lakka

    2010-10-01

    The role of angiogenesis in the transformation of peripheral neurofibroma (PNF) to malignant peripheral nerve sheath tumor (MPNST) in neurofibromatosis type 1 (NF1) remains elusive and forms the objective of this study. Archival tissue from 5 children with NF1 and PNF, who developed MPNST between the ages of 8 and 15 years were analyzed for differences in microvasculature. The role of proangiogenic growth factors such as Vascular Endothelial Growth Factor (VEGF), and its receptors Flk-1 and Flt-1, and vessel maturity, defined as von Willebrand factor (vWf), α-smooth muscle actin+ (SMA+), were evaluated by immuno-histochemistry. A qualitative evaluation of the vasculature showed predominantly α-SMA+/vWf+ more stable vessels in PNF, and an irregular meshwork of α-SMA-/vWf+ endothelial cells structures in MPNST. In NF and PNF tumor cells were VEGF-, in contrast to VEGF+ tumor cells in MPNST. If present, the VEGF stain was confined mainly to the perivascular spaces in PNF, unlike the mainly stromal VEGF stain in MPNST. VEGF receptors also manifested a tumor stage-specific pattern. Flk-1 and Flt-1 were restricted to the mature, well-formed vasculature in PNF, but exhibited a diffuse pattern in MPNST. Our study provides a rare opportunity to document consistent and histologically detectable differences in the vascular organization of PNF and MPNST. It permits a pair-wise evaluation of the malignant conversion of benign PNF into its malignant counterpart, in the same patients. The phenotypic variations and characteristics of the vessels in these tumors are consistent with the idea that a strong proangiogenic drive contributes to the progressive growth in MPNST.

  7. Pre-operative declining proportion of fractional anisotropy of trigeminal nerve is correlated with the outcome of micro-vascular decompression surgery.

    PubMed

    Chen, Fanfan; Chen, Lei; Li, Wei; Li, Ling; Xu, Xiangdong; Li, Weimin; Le, Wuhua; Xie, Wei; He, Hua; Li, Peng

    2016-07-16

    Type 2 trigeminal neuralgia (TN) is an intractable neuropathic pain syndrome compared with type 1 TN because of the difficulty of diagnosis as well as the unsatisfactory prognosis. Neurovascular compression (NVC) is considered the major pathology of TN. Routine magnetic resonance imaging (MRI) sequences are inadequate for revealing the effect of NVC which is related to the surgical decision and outcome. The decreasing of fractional anisotropy (FA), one of the MRI diffusion tensor imaging (DTI) metrics, is correlated with the demyelination of trigeminal nerve (TGN) that reveal the severity of NVC. A retrospective review of patients treated with micro-vascular decompression (MVD) surgery was undertaken. All the patients were diagnosed as type 2 TN. FA of TGN of both sides were measured. The FA declining proportion = ((the mean FA value of healthy lateral)-(the mean FA value of the symptomatic lateral))/(the mean FA value of healthy lateral). Declining proportion of FA value, discovery of surgery and outcome of MVD were recorded and analyzed. Logistic regression analysis and linear regression analysis were employed to analyze the risk factors of declining proportion of FA value and MVD outcome. Nineteen patients were assessed in our study. The average declining proportion of FA value for all patients was 0.25 ± 0.12. The average declining proportion of FA value of "success" and "failure" group was 0.32 ± 0.09 to 0.14 ± 0.10 (P = 0.002 < 0.05). The declining proportion of FA value of artery (including the artery plus vein situation) was 0.34 ± 0.06 in contrast to 0.15 ± 0.08 of vein (P = 0.000 < 0.05). MVD outcome was correlated with declining proportion of FA value (AUC = 0.900). Furthermore, declining proportion of FA value was higher in arterial compression situation. FA value quantitatively showed the alteration of TGN caused by NVC. It provided direct evidence about the effect of NVC which facilitated the diagnosis and surgical decision of type 2 TN

  8. Cadaveric study of zone 2 flexor hallucis longus tendon sheath.

    PubMed

    Lui, Tun Hing; Chan, Kwok Bill; Chan, Lap Ki

    2010-06-01

    The purpose of this study was to investigate the anatomy of the zone 2 flexor hallucis longus (FHL) tendon sheath. Dissection of the zone 2 FHL tendon sheath was performed in 12 feet of 6 cadavers. The tendon sheath was subdivided into proximal fibrous (zone 2A) and distal fascial (zone 2B) parts. The lengths of the zone 2A and 2B FHL tendon were measured and represented the length of the corresponding tendon sheaths, and the relation of the medial plantar nerve to each part of the zone 2 FHL tendon sheath was studied. In all specimens there were fibrous and fascial components of the zone 2 FHL tendon sheath. The medial plantar nerve crossed the zone 2B tendon sheaths and then became plantar lateral to the sheath in 7 specimens. The distance between the medial plantar nerve and the orifice of the zone 2A tendon sheath averaged 7.6 mm. The distance between the medial plantar nerve and the junction between zones 2A and 2B averaged 3.2 mm. The distance between the medial plantar nerve and the distal end of the zone 2B tendon sheath averaged 4.2 mm. The mean length of the zone 2A tendon sheath was 35.9 mm, and the mean length of the zone 2B tendon sheath was 30.5 mm. The zone 2 FHL tendon sheath can be subdivided into a proximal fibrous zone (2A) and a distal fascial zone (2B). Because of the close proximity of the medial plantar nerve to the tendon sheath, there is a significant risk of iatrogenic nerve injury when surgical procedures are performed in zone 2B. An understanding of the anatomy of the zone 2 FHL tendon sheath is useful for the safe practice of zone 2 FHL tendoscopy. Copyright (c) 2010 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  9. Bilateral failure of adduction following orbital decompression.

    PubMed Central

    Kinsella, F; Kyle, P; Stansfield, A

    1990-01-01

    We report a case of bilateral complete failure of adduction following bilateral translid antralethmoidal orbital decompression. We believe the probable mechanism is neuropraxia (temporary dysfunction) of the third cranial nerves' supply to the medial recti, owing to these nerves' occupying an anatomically abnormal position. Partial recovery of adduction occurred over the ensuing six months. Images PMID:2337551

  10. Loss of H3K27 tri-methylation is a diagnostic marker for malignant peripheral nerve sheath tumors and an indicator for an inferior survival.

    PubMed

    Cleven, Arjen H G; Sannaa, Ghadah A Al; Briaire-de Bruijn, Inge; Ingram, Davis R; van de Rijn, Matt; Rubin, Brian P; de Vries, Maurits W; Watson, Kelsey L; Torres, Kelia E; Wang, Wei-Lien; van Duinen, Sjoerd G; Hogendoorn, Pancras C W; Lazar, Alexander J; Bovée, Judith V M G

    2016-06-01

    Malignant peripheral nerve sheath tumors (MPNSTs) are aggressive sarcomas that can show overlapping features with benign neurofibromas as well as high-grade sarcomas. Additional diagnostic markers are needed to aid in this often challenging differential diagnosis. Recently mutations in two critical components of the polycomb repressor 2 (PRC2) complex, SUZ12 and EED, were reported to occur specifically in MPNSTs while such mutations are absent in neurofibromas, both in the setting of neurofibromatosis (NF) and sporadic cases. Furthermore, both SUZ12 and EED mutations in MPNSTs were associated with loss of H3K27 tri-methylation, a downstream target of PRC2. Therefore, we tested whether H3K27me3 immunohistochemistry is useful as a diagnostic and prognostic marker for MPNSTs. We performed H3K27me3 immunohistochemistry in 162 primary MPNSTs, 97 neurofibromas and 341 other tumors using tissue microarray. We observed loss of H3K27me3 in 34% (55/162) of all MPNSTs while expression was retained in all neurofibromas including atypical (n=8) and plexiform subtypes (n=24). Within other tumors we detected loss of H3K27me3 in only 7% (24/341). Surprisingly, 60% (9/15) of synovial sarcomas and 38% (3/8) of fibrosarcomatous dermatofibrosarcoma protuberans (DFSP) showed loss of H3K27 trimethylation. Only 1 out of 44 schwannomas showed loss of H3K27me3 and all 4 perineuriomas showed intact H3K27me3. Furthermore, MPNSTs with loss of H3K27 tri-methylation showed inferior survival compared with MPNSTs with intact H3K27 tri-methylation, which was validated in two independent cohorts. Our results indicate that H3K27me3 immunohistochemistry is useful as a diagnostic marker, in which loss of H3K27me3 favors MPNST above neurofibroma. However, H3K27me3 immunohistochemistry is not suitable to distinguish MPNST from its morphological mimicker synovial sarcoma or fibrosarcomatous DFSP. Since loss of H3K27 tri-methylation was related to poorer survival in MPNST, chromatin modification mediated

  11. NF1 deficiency causes Bcl-xL upregulation in Schwann cells derived from neurofibromatosis type 1-associated malignant peripheral nerve sheath tumors.

    PubMed

    Park, Ho-Jin; Lee, Su-Jin; Sohn, Young Bae; Jin, Hyun-Seok; Han, Jae-Ho; Kim, Young-Bae; Yim, Hyunee; Jeong, Seon-Yong

    2013-02-01

    Since the bi-allelic inactivation of both neurofibromin 1 (NF1) gene alleles (NF1(-/-)) in Schwann cells (SCs) is common in both benign plexiform neurofibromas (PNs) and malignant peripheral nerve sheath tumors (MPNSTs) in patients with neurofibromatosis type 1 (NF1), other genetic alterations in SCs may be required for tumor progression of PNs to MPNSTs. We found that the anti-apoptotic Bcl-xL protein is upregulated in MPNST tissues compared to PN tissues from patients with NF1 by immunohistological staining. In addition, we investigated whether Bcl-xL is upregulated in SCs derived from MPNSTs and found a significantly higher Bcl-xL expression level in sNF96.2 MPNST-derived SCs compared to normal human SCs (HSCs). We also discovered that the increased Bcl-xL expression caused an increase in drug resistance to doxorubicin in MPNST-derived SCs. Manipulation of NF1 gene expression levels by treatment with small interfering RNA (siRNA) and overexpression of the neurofibromin GAP-related domain (NF1-GRD) demonstrated that upregulated Bcl-xL expression in MPNST-derived SCs was caused by NF1 deficiency. Treatment with the Erk1/2 inhibitor, PD98059, resulted in a slight increase in Bcl-xL levels in neurofibromin-depleted normal HSCs, indicating that Bcl-xL upregulation in MPNST-derived SCs is mediated by activated Erk1/2, which is a Ras downstream protein regulated by neurofibromin. As the reduction of Bcl-xL expression restored sensitivity to doxorubicin-induced apoptosis in sNF96.2 cells, we examined the effect of the small molecule Bcl-xL inhibitor ABT-737 on sNF96.2 cells. A very low dose of ABT-737 combined with doxorubicin synergistically enhanced sensitivity to doxorubicin-induced apoptosis in sNF96.2 cells, suggesting that ABT-737 and doxorubicin may be a good combination to effectively treat NF1-associated MPNSTs with minimal side-effects. Collectively, our results suggest that upregulation of Bcl-xL in MPNST-derived SCs may be caused by the NF1 deficiency

  12. Molecular characterization of permanent cell lines from primary, metastatic and recurrent malignant peripheral nerve sheath tumors (MPNST) with underlying neurofibromatosis-1.

    PubMed

    Fang, Yuqiang; Elahi, Abul; Denley, Ryan C; Rao, Pulivarthi H; Brennan, Murray F; Jhanwar, Suresh C

    2009-04-01

    Malignant peripheral nerve sheath tumors (MPNSTs) develop in patients with underlying NF1, and usually arise as a result of malignant transformation of a pre-existing plexiform neurofibroma. The clonal cytogenetic abnormalities reported in primary MPNST include complex karyotypes with chromosome numbers in the triploid or tetraploid range with recurrent abnormalities of several chromosomes including losses or imbalances. As a prelude to cell biological, pharmacological, and functional studies to investigate pathways and gene(s) associated with multistep tumorigenesis, which includes progression, metastasis and resistance to therapy in MPNST, detailed molecular cytogenetic and genetic analyses of cell lines from primary, metastatic and recurrent MPNST with underlying NF1 disorder have been performed. The clonal cytogenetic abnormalities detected in the primary tumor cell line were similar to those observed in primary cultures of this tumor. Due to the complexity of the rearrangements seen by G-banded karyotype analysis, further characterization of the clonal abnormalities in these three cell lines was performed by molecular cytogenetic techniques, including CGH and SKY. CGH analysis detected recurrent deletions of 9p, 12q21-q32, complete losses of the X-chromosome, and gains of the chromosomal segment 17q25 in all three cell lines. SKY analysis detected extensive clonal abnormalities in these cell lines. The nature and the alterations of the cell cycle regulators, particularly those associated with G1-S checkpoints and known to be deregulated in MPNST, were studied. These cell cycle regulators included those associated with Rb1-cyclin D1 and the p53 pathways. The findings are consistent with the argument that an imbalance between the cyclin activators of CDKs and inhibitory proteins such as p16 result in uncontrollable proliferation in the cell lines, associated with progression of the disease. LOH and expression of the p53 gene in metastatic and recurrent cell

  13. Optic nerve sheath diameter threshold by ocular ultrasonography for detection of increased intracranial pressure in Korean adult patients with brain lesions

    PubMed Central

    Lee, Si Un; Jeon, Jin Pyeong; Lee, Hannah; Han, Jung Ho; Seo, Mingu; Byoun, Hyoung Soo; Cho, Won-Sang; Ryu, Ho Geol; Kang, Hyun-Seung; Kim, Jeong Eun; Kim, Heung Cheol; Jang, Kyung-Sool

    2016-01-01

    Abstract Optic nerve sheath diameter (ONSD) seen on ocular US has been associated with increased intracranial pressure (IICP). However, most studies have analyzed normal range of ONSD and its optimal cut-off point for IICP in Caucasian populations. Considering ONSD differences according to ethnicity, previous results may not accurately reflect the association between IICP and ONSD in Koreans. Therefore, we conducted this study to investigate normal range of ONSD and its optimal threshold for detecting IICP in Korean patients. This prospective multicenter study was performed for patients with suspected IICP. ONSD was measured 3 mm behind the globe using a 13-MHz US probe. IICP was defined as significant brain edema, midline shift, compression of ventricle or basal cistern, effacement of sulci, insufficient gray/white differentiation, and transfalcine herniation by radiologic tests. The results of the ONSD are described as the median (25th–75th percentile). The differences of ONSD according to disease entity were analyzed. A receiver operator characteristic (ROC) curve was generated to determine the optimal cut-off point for identifying IICP. A total of 134 patients were enrolled. The patients were divided into 3 groups as follows: patients with IICP, n = 81 (60.5%); patients without IICP, n = 27 (20.1%); and control group, n = 26 (19.4%). ONSD in patients with IICP (5.9 mm [5.8–6.2]) is significantly higher than those without IICP (5.2 mm [4.8–5.4]) (P < 0.01) and normal control group (4.9 mm [4.6–5.2]) (P < 0.001). Between patients without IICP and normal control group, the difference of ONSD did not reach statistical significance (P = 0.31). ONSD >5.5 mm yielded a sensitivity of 98.77% (95% CI: 93.3%–100%) and a specificity of 85.19% (95% CI: 66.3%–95.8%). In conclusion, the optimal cut-off point of ONSD for identifying IICP was 5.5 mm. ONSD seen on ocular US can be a feasible method for detection and serial monitoring of ICP in

  14. Decompression Theory.

    DTIC Science & Technology

    1980-06-25

    new experiments at 30 m ( 4 ATA) is appropriate for comparing N2 and He with respect to half times and surfacing ratios. Table 4 demonstrates the...THEORY C4 i t44 4 ’I9 41-*1 ai4 p80 7 10 009 UM"tUBNC*nm N4MDOf 29WS (DT) 6-25-80 The Seventeenth Undersea Medical Society Workshop DECOMPRESSION...Hamilton, Jr., Ph.D. Edward L Beckman, M.D. Hamilton Research Ltd. University of Hawaii 80 Grove Street School of Medicine Tarrytown, New York 10591

  15. Endoscopic Decompression of the First Branch of the Lateral Plantar Nerve and Release of the Plantar Aponeurosis for Chronic Heel Pain.

    PubMed

    Lui, Tun Hing

    2016-06-01

    Entrapment of the first branch of the lateral plantar nerve is a commonly missed cause of recalcitrant plantar heel pain. The diagnosis is made on a clinical ground with maximal tenderness at the site of nerve entrapment. Treatment of the nerve entrapment is similar to that for plantar fasciitis, with rest, activity modification, nonsteroidal anti-inflammatory drugs, stretching exercise, and local steroid injection. Surgical release of the deep abductor hallucis fascia is indicated when conservative treatment failed. Endoscopic release of the nerve through the dorsal and plantar portals, as well as endoscopic plantar aponeurosis release, is a feasible approach.

  16. Endoscopically Assisted Anterior Subcutaneous Transposition of Ulnar Nerve.

    PubMed

    Lui, Tun Hing

    2016-06-01

    Ulnar nerve compression at the elbow is the most common neuropathy of the upper extremity. Surgical options include in situ decompression, decompression with anterior transposition of the ulnar nerve, and medial epicondylectomy with or without decompression. With the advancement of endoscopic surgery, techniques of endoscopic in situ decompression of the ulnar nerve and endoscopic anterior transposition of ulnar nerve have been reported. This article describes a technique of endoscopically assisted anterior subcutaneous transposition of ulnar nerve that is composed of an open release and mobilization of the ulnar nerve at and distal to the cubital tunnel and endoscopic release and mobilization of the ulnar nerve proximal to the cubital tunnel.

  17. The effects of tumor location on diagnostic criteria for canine malignant peripheral nerve sheath tumors (MPNSTs) and the markers for distinction between canine MPNSTs and canine perivascular wall tumors.

    PubMed

    Suzuki, S; Uchida, K; Nakayama, H

    2014-07-01

    Canine malignant peripheral nerve sheath tumors (MPNSTs) occur not only in the peripheral nervous system (PNS) but also in soft tissue and various organs (non-PNS). The most important diagnostic criterion is proof of peripheral nerve sheath origin. This is difficult in non-PNS MPNSTs, and its differential diagnosis is challenging. Canine perivascular wall tumors (PWTs) also commonly arise in soft tissue. Their histopathological features are quite similar to those of canine MPNSTs, making their differential diagnosis challenging. To elucidate whether the morphological features are applicable to diagnose non-PNS MPNSTs and to demonstrate useful markers for distinction between canine MPNSTs and PWTs, the authors examined 30 canine MPNSTs and 31 PWTs immunohistochemically for S100, nestin, NGFR, Olig2, claudin-1, CD57, PRX, α-SMA, desmin, and calponin. Among canine MPNSTs, the PNS tumors displayed significantly higher S100 and Olig2 expression than the non-PNS tumors. The expression levels of the other markers did not differ significantly, suggesting that the same morphological diagnostic criteria are applicable regardless of their location. The PWT cells displayed significantly weaker immunoreactivity than MPNSTs to markers used except α-SMA and desmin. Cluster analysis sorted most canine MPNSTs and PWTs into 2 distinctly different clusters, whereas 3 MPNSTs and 6 PWTs were assigned to the opposing cluster. These 3 MPNSTs were negative for almost all markers, while these 6 PWTs were positive for only neuronal markers. In particular, NGFR and Olig2 were almost negative in the rest of PWT cases. These findings suggest that NGFR and Olig2 are useful to distinguish these 2 tumors.

  18. Nerve root distribution of deltoid and biceps brachii muscle in cervical spondylotic myelopathy: a potential risk factor for postoperative shoulder muscle weakness after posterior decompression.

    PubMed

    Yonemura, Hiroshi; Kaneko, Kazuo; Taguchi, Toshihiko; Fujimoto, Hideaki; Toyoda, Kouichiro; Kawai, Shinya

    2004-01-01

    To investigate the nerve root distribution of deltoid and biceps brachii muscle, compound muscle action potentials (CMAPs) were recorded intraoperatively following nerve root stimulation in cervical spondylotic myelopathy. A total of 19 upper limbs in 12 patients aged 55-72 years (mean, 65.5 years) with cervical spondylotic myelopathy were examined. CMAPs were recorded from deltoid and biceps brachii muscle following C5 and C6 root stimulation. Although both C5 and C6 roots were innervated for deltoid and biceps brachii muscle in all subjects, the amplitude ratio of CMAPs (C5/C6) differed individually depending on the symptomatic intervertebral levels of the spinal cord. The C5 root predominantly innervated both deltoid and biceps brachii in patients with symptomatic cord lesions at the C4-C5 intervertebral level compared to patients with symptomatic cord lesions at the C5-C6 intervertebral level. Although no patients sustained postoperative radiculopathy in our study, severe weakness and unfavorable recovery are expected when the C5 root in patients with C4-C5 myelopathy is damaged. From the electrophysiological aspect, C4-C5 cord lesions are likely to be a potential risk factor for postoperative shoulder muscle weakness in patients with compressive cervical myelopathy.

  19. Communication through plasma sheaths

    SciTech Connect

    Korotkevich, A. O.; Newell, A. C.; Zakharov, V. E.

    2007-10-15

    We wish to transmit messages to and from a hypersonic vehicle around which a plasma sheath has formed. For long distance transmission, the signal carrying these messages must be necessarily low frequency, typically 2 GHz, to which the plasma sheath is opaque. The idea is to use the plasma properties to make the plasma sheath appear transparent.

  20. Pre-Operative Image-based Segmentation of the Cranial Nerves and Blood Vessels in Microvascular Decompression: Can we Prevent Unnecessary Explorations?

    PubMed Central

    Dolati, P; Golby, A; Eichberg, D; Abolfotoh, M; Dunn, IF; Mukundan, S; Hulou, MM; Al-Mefty, O

    2016-01-01

    Objectives This study was conducted to validate the accuracy of image-based pre-operative segmentation using the gold standard endoscopic and microscopic findings for localization and pre-operative diagnosis of the offensive vessel. Patients and Methods Fourteen TN and 6 HS cases were randomly selected. All patients had 3T MRI, which included thin-sectioned 3D space T2, 3D Time of Flight and MPRAGE Sequences. Imaging sequences were loaded in BrainLab iPlanNet and fused. Individual segmentation of the affected cranial nerves and the compressing vascular structure was performed by a neurosurgeon, and the results were compared with the microscopic and endoscopic findings by two blinded neurosurgeons. For each case, at least three neurovascular landmarks were targeted. Each segmented neurovascular element was validated by manual placement of the navigation probe over each target, and errors of localization were measured in mm. Results All patients underwent retro-sigmoid craniotomy and MVD using both microscope and endoscope. Based on image segmentation, the compressing vessel was identified in all cases except one, which was also negative intraoperatively. Perfect correspondence was found between image-based segmentation and endoscopic and microscopic images and videos (Dice coefficient of 1). Measurement accuracy was 0.45+/-0.21 mm (mean +/-SD). Conclusion Image-based segmentation is a promising method for pre-operative identification and localization of offending blood vessels causing HFS and TN. Using this method may prevent some unnecessary explorations on especially atypical cases with no vascular contacts. However, negative pre-operative image segmentation may not preclude one from exploration in classic cases of TN or HFS. A multicenter study with larger number of cases is recommended. PMID:26476700

  1. Neurovascular Bundle Decompression without Excessive Dissection for Tarsal Tunnel Syndrome

    PubMed Central

    KIM, Kyongsong; ISU, Toyohiko; MORIMOTO, Daijiro; SASAMORI, Toru; SUGAWARA, Atsushi; CHIBA, Yasuhiro; ISOBE, Masahiro; KOBAYASHI, Shiro; MORITA, Akio

    2014-01-01

    Tarsal tunnel syndrome (TTS) is an entrapment neuropathy of the posterior tibial nerve and its branches in the tarsal tunnel. We present our less invasive surgical treatment of TTS in 69 patients (116 feet) and their clinical outcomes. The mean follow-up period was 64.6 months. With the patient under local anesthesia we use a microscope to perform sharp dissection of the flexor retinaculum and remove the connective tissues surrounding the posterior tibial nerve and vessels. To prevent postoperative adhesion and delayed neuropathy, decompression is performed to achieve symptom improvement without excessive dissection. Decompression is considered complete when the patient reports intraoperative symptom abatement and arterial pulsation is sufficient. The sensation of numbness and/or pain and of foreign substance adhesion was reduced in 92% and 95% of our patients, respectively. In self-assessments, 47 patients (68%) reported the treatment outcome as satisfactory, 15 (22%) as acceptable, and 7 (10%) were dissatisfied. Of 116 feet, 4 (3%) required re-operation, initial decompression was insufficient in 2 feet and further decompression was performed; in the other 2 feet improvement was achieved by decompression of the distal tarsal tunnel. Our surgical method involves neurovascular bundle decompression to obtain sufficient arterial pulsation. As we use local anesthesia, we can confirm symptom improvement intraoperatively, thereby avoiding unnecessary excessive dissection. Our method is simple, safe, and without detailed nerve dissection and it prevents postoperative adhesion. PMID:25367582

  2. Neurovascular bundle decompression without excessive dissection for tarsal tunnel syndrome.

    PubMed

    Kim, Kyongsong; Isu, Toyohiko; Morimoto, Daijiro; Sasamori, Toru; Sugawara, Atsushi; Chiba, Yasuhiro; Isobe, Masahiro; Kobayashi, Shiro; Morita, Akio

    2014-01-01

    Tarsal tunnel syndrome (TTS) is an entrapment neuropathy of the posterior tibial nerve and its branches in the tarsal tunnel. We present our less invasive surgical treatment of TTS in 69 patients (116 feet) and their clinical outcomes. The mean follow-up period was 64.6 months. With the patient under local anesthesia we use a microscope to perform sharp dissection of the flexor retinaculum and remove the connective tissues surrounding the posterior tibial nerve and vessels. To prevent postoperative adhesion and delayed neuropathy, decompression is performed to achieve symptom improvement without excessive dissection. Decompression is considered complete when the patient reports intraoperative symptom abatement and arterial pulsation is sufficient. The sensation of numbness and/or pain and of foreign substance adhesion was reduced in 92% and 95% of our patients, respectively. In self-assessments, 47 patients (68%) reported the treatment outcome as satisfactory, 15 (22%) as acceptable, and 7 (10%) were dissatisfied. Of 116 feet, 4 (3%) required re-operation, initial decompression was insufficient in 2 feet and further decompression was performed; in the other 2 feet improvement was achieved by decompression of the distal tarsal tunnel. Our surgical method involves neurovascular bundle decompression to obtain sufficient arterial pulsation. As we use local anesthesia, we can confirm symptom improvement intraoperatively, thereby avoiding unnecessary excessive dissection. Our method is simple, safe, and without detailed nerve dissection and it prevents postoperative adhesion.

  3. Surgical decompression for notalgia paresthetica: a case report.

    PubMed

    Williams, Eric H; Rosson, Gedge D; Elsamanoudi, Ibrahim; Dellon, A Lee

    2010-01-01

    Notalgia paresthetica is a rare nerve compression. From the Greek word noton, meaning "back," and algia, meaning "pain," "notalgia paresthetica" implies that symptoms of burning pain, itching, and/or numbness in the localized region between the spinous processes of T2 through T6 and the medial border of the scapula constitute a nerve compression syndrome. The compressed nerve is the dorsal branch of the spinal nerve. It is compressed by the paraspinous muscles and fascia against the transverse process of these spinal segments. This is the first report of symptomatic relief by decompression of this nerve.

  4. Outcomes of surgical paraclavicular thoracic outlet decompression.

    PubMed

    Desai, Sapan S; Toliyat, Mohammad; Dua, Anahita; Charlton-Ouw, Kristofer M; Hossain, Monir; Estrera, Anthony L; Safi, Hazim J; Azizzadeh, Ali

    2014-02-01

    Thoracic outlet syndrome (TOS) is a constellation of signs and symptoms caused by compression of the neurovascular structures in the thoracic outlet. These structures include the brachial plexus, the subclavian vein, and the subclavian artery, resulting in neurogenic (NTOS), venous (VTOS), and arterial (ATOS) types of TOS, respectively. The purpose of this study was to evaluate the outcomes of paraclavicular surgical decompression for TOS. A prospective analysis of patients who underwent surgical decompression for TOS at a newly established center was performed. Diagnosis of TOS was based on clinical history, a physical examination, and additional diagnostic studies. The indication for surgery in patients diagnosed with NTOS was the presence of persistent symptoms after a trial of physical therapy. Primary outcomes were assessed according to Derkash's classification as excellent, good, fair, and poor. Secondary outcomes included mortality, complications, and duration of hospital stay. Between August 2004 and June 2011, 40 paraclavicular decompression procedures were performed on 36 patients (16 men) with TOS. The mean age was 36.5 years (range: 15-68). Bilateral decompression was performed on 4 patients. The types were NTOS (n = 19; 48%), VTOS (n = 16; 40%), and ATOS (n = 5; 12%). In addition to pain, the most common presenting symptom was numbness in NTOS, swelling in VTOS, and coolness in ATOS. A history of trauma was present in 22.2%. Two patients suffered from recurrent symptoms after previous transaxillary first rib resection for VTOS at another institution. Diagnostic tests performed included nerve conduction studies (43%), venogram (40%), and arteriogram (20%). All patients underwent paraclavicular decompression, which included radical anterior and partial middle scalenectomy, brachial plexus neurolysis, and first rib resection. The first rib resection was partial, through a supraclavicular only approach in NTOS and ATOS patients (60%) or complete, through a

  5. Meralgia paresthetica: etiology, diagnosis, and outcome of surgical decompression.

    PubMed

    Nahabedian, M Y; Dellon, A L

    1995-12-01

    Entrapment of the lateral femoral cutaneous (LFC) nerve as a source of anterolateral thigh dysesthesias has been recognized for 100 years. Despite this historic recognition, its diagnosis today is often delayed, and definitive treatment of refractory cases by surgical decompression rarely reported. This study describes 26 LFC entrapments in 23 patients whose etiologies include iliac crest bone graft harvesting, seat belt injury associated with motor vehicle accident, and diabetes. Twenty-two of the 23 patients (25 of the 26 entrapments) achieved good to excellent outcomes following surgical decompression of the LFC nerve.

  6. Treatment of hemimasticatory spasm with microvascular decompression.

    PubMed

    Wang, Yong-Nan; Dou, Ning-Ning; Zhou, Qiu-Meng; Jiao, Wei; Zhu, Jin; Zhong, Jun; Li, Shi-Ting

    2013-01-01

    Hemimasticatory spasm is a rare disorder characterized by paroxysmal involuntary contraction of the jaw-closing muscles. As the ideology and pathogenesis of the disease are still unclear, there has been no treatment that could give rise to a good outcome so far. Herein, we tried to use surgical management to cure the disease. Six patients with the disease were included in this study. These patients underwent microvascular decompression of the motor fibers of the trigeminal root. After the operation, all faces of the patients felt relaxed at varied degrees, except for 1 patient. Our study showed that microvascular decompression of the trigeminal nerve could lead to a better outcome. However, a control study with a large sample is needed before this technique is widely used.

  7. Cutaneous decompression sickness.

    PubMed

    Tasios, Konstantinos; Sidiras, Georgios Gr; Kalentzos, Vasileios; Pyrpasopoulou, Athina

    2014-03-01

    A probable case of decompression illness with associated cutis marmorata is presented, which regressed over a few hours with oxygen breathing and after intravenous methylprednisolone and fluid resuscitation without recompression. He was eventually transferred for hyperbaric treatment some 10 hours post dive. Cutaneous decompression illness is not associated with high mortality per se, but prompt and accurate recognition is warranted, as it may represent a prodromal feature of potentially life-threatening complications. However, in this case, as differential diagnosis, an allergic reaction remains possible.

  8. Decompression schedule optimization with an isoprobabilistic risk of decompression sickness.

    PubMed

    Horn, Beverley J; Wake, Graeme C; Anthony, T Gavin

    2006-01-01

    Divers use decompression schedules to reduce the probability of occurrence of decompression sickness when returning to the surface at the end of a dive. The probability of decompression sickness resulting from these schedules varies across different dives and the models used to generate them. Usually the diver is unaware of this variance in risk. This paper describes an investigation into the feasibility of producing optimized iso-probabilistic decompression schedules that minimize the time it takes for a diver to reach the surface. The decompression schedules were optimized using the sequential quadratic programming method (SQP), which minimizes the ascent time for a given probability of decompression sickness. The U.S. linear-exponential multi-gas model was used to calculate an estimate of the probability of decompression sickness for a given dive. In particular 1.3-bar oxygen in helium rebreather bounce dives to between 18 m and 81 m were considered and compared against the UK Navy QinetiQ 90 tables for a similar estimate of probability of decompression sickness. The SQP method reliably produced schedules with fast and stable convergence to an optimized solution. Comparison of the optimized decompression schedules with the QinetiQ 90 schedules showed similar stop times for shallow dives to 18 m. For dives with a maximum depth of 39 m to 81 m, optimizing the decompression resulted in savings in decompression time of up to 30 min. This paper has shown that it is feasible to produce optimized iso-probabilistic decompression tables given a reliable risk model for decompression sickness and appropriate dive trials.

  9. Intra-operative neurophysiology during microvascular decompression for hemifacial spasm.

    PubMed

    Fernández-Conejero, I; Ulkatan, S; Sen, C; Deletis, V

    2012-01-01

    There is evidence that primary hemifacial spasm (HFS) in the majority of patients is related to a vascular compression of the facial nerve at its root exit zone (REZ). As a consequence, the hyperexcitability of facial nerve generates spasms of the facial muscles. Microvascular decompression (MVD) of the facial nerve near its REZ has been established as an effective treatment of HFS. Intra-operative disappearance of abnormal muscle responses (lateral spread) elicited by stimulating one of the facial nerve branches has been used as a method to predict MVD effectiveness. Other neurophysiologic techniques, such as facial F-wave, blink reflex and facial corticobulbar motor evoked potentials (FCoMEP), are feasible to intra-operatively study changes in excitability of the facial nerve and its nucleus during MVDs. Intra-operative neuromonitoring with the mentioned techniques allows a better understanding of HFS pathophysiology and helps to optimise the MVD.

  10. Sheath energy transmission in a collisional plasma with collisionless sheath

    SciTech Connect

    Tang, Xian-Zhu Guo, Zehua

    2015-10-15

    Sheath energy transmission governs the plasma energy exhaust onto a material surface. The ion channel is dominated by convection, but the electron channel has a significant thermal conduction component, which is dominated by the Knudsen layer effect in the presence of an absorbing wall. First-principle kinetic simulations reveal a robustly supersonic sheath entry flow. The ion sheath energy transmission and the sheath potential are accurately predicted by a sheath model of truncated bi-Maxwellian electron distribution. The electron energy transmission is further enhanced by a parallel heat flux of the perpendicular degrees of freedom.

  11. THE AMELIORATIVE EFFECTS OF HEPARIN AND DEPOLYMERIZED HYALURONATE ON DECOMPRESSION SICKNESS IN RATS,

    DTIC Science & Technology

    DECOMPRESSION SICKNESS, DRUGS), (* MUCOPOLYSACCHARIDES , DECOMPRESSION SICKNESS), (*HEPARIN, DECOMPRESSION SICKNESS), (*ANTICOAGULANTS, DECOMPRESSION SICKNESS), RATS, COUMARINS, BLOOD COAGULATION, DOSAGE, LIPIDS, CANADA

  12. Continuum kinetic and multi-fluid simulations of classical sheaths

    NASA Astrophysics Data System (ADS)

    Cagas, P.; Hakim, A.; Juno, J.; Srinivasan, B.

    2017-02-01

    The kinetic study of plasma sheaths is critical, among other things, to understand the deposition of heat on walls, the effect of sputtering, and contamination of the plasma with detrimental impurities. The plasma sheath also provides a boundary condition and can often have a significant global impact on the bulk plasma. In this paper, kinetic studies of classical sheaths are performed with the continuum kinetic code, Gkeyll, which directly solves the Vlasov-Maxwell equations. The code uses a novel version of the finite-element discontinuous Galerkin scheme that conserves energy in the continuous-time limit. The fields are computed using Maxwell equations. Ionization and scattering collisions are included; however, surface effects are neglected. The aim of this work is to introduce the continuum kinetic method and compare its results with those obtained from an already established finite-volume multi-fluid model also implemented in Gkeyll. Novel boundary conditions on the fluids allow the sheath to form without specifying wall fluxes, so the fluids and fields adjust self-consistently at the wall. The work presented here demonstrates that the kinetic and fluid results are in agreement for the momentum flux, showing that in certain regimes, a multi-fluid model can be a useful approximation for simulating the plasma boundary. There are differences in the electrostatic potential between the fluid and kinetic results. Further, the direct solutions of the distribution function presented here highlight the non-Maxwellian distribution of electrons in the sheath, emphasizing the need for a kinetic model. The densities, velocities, and the potential show a good agreement between the kinetic and fluid results. However, kinetic physics is highlighted through higher moments such as parallel and perpendicular temperatures which provide significant differences from the fluid results in which the temperature is assumed to be isotropic. Besides decompression cooling, the heat flux

  13. Neurophysiological assessment of divers with medical histories of neurological decompression illness.

    PubMed Central

    Murrison, A W; Glasspool, E; Pethybridge, R J; Francis, T J; Sedgwick, E M

    1994-01-01

    OBJECTIVE--To examine the possibility that subclinical damage may persist after clinical recovery from neurological decompression illness. METHODS--The neuraxes of 71 divers with medical histories of neurological decompression illness and 37 non-diver controls were examined by recording the somatosensory evoked potentials produced on stimulation of the posterior tibial and median nerves. RESULTS--Although the tests gave some objective support for the presence of "soft" residual neurological symptoms and signs, no evidence was given for the presence of subclinical damage. CONCLUSIONS--The contention that neurological damage persists after full clinical recovery from the neurological decompression illness was not supported. PMID:7849848

  14. Decompression apparatus for engines

    SciTech Connect

    Harada, M.

    1987-09-29

    In a decompression apparatus for an engine having a camshaft, a cam gear is described having a longitudinal bore along a central axis thereof, and a tappet engaging with an actuating cam on the camshaft. The improvement comprises: a releasing lever comprising a shaft and a weight secured to the shaft; the shaft forming a semicircular cam at one end; the camshaft having a first recess in a longitudinal direction; the cam gear having a second recess adjacent the bore; a bearing member for engaging with the first and second recesses and for rotatably supporting the shaft; a flat bottom notch for supporting the semicircular cam and being provided on the camshaft lose to the actuating cam; and the semicircular cam being arranged to project beyond a periphery of the actuating cam when engine operation is stopped.

  15. Vein, silastic, and polyglycolic acid fine mesh: a comparative study in peripheral nerve repair.

    PubMed

    Lolley, R D; Bose, W J; Bastian, F; Bassam, B; Meyer, F N; Anderson, L D

    1995-09-01

    We investigated three sheathing materials (autogenous vein, silastic, and polyglycolic acid fine mesh) using the rat model. Forty rats were divided into five groups of eight animals each. Group A animals underwent transection of the sciatic nerve but had no repair. In Group B, a standard epineural repair was performed. In Groups C, D, and E, the nerve was repaired as in Group B with the addition of autogenous vein, Silastic, and polyglycolic acid fine mesh sheaths, respectively. Nerve regeneration and function were assessed using sciatic functional index, nerve conduction studies, and light microscopy. Sheathing methods showed no statistically significant advantage to standard epineural repair without a sheath.

  16. [Clinical course of decompressive surgery for the treatment of lumbar stenosis].

    PubMed

    Cano-Rodríguez, A I; González-Moga, A

    2016-01-01

    Several authors and publications have focused on comparing the clinical course of nerve root decompressive surgery, with or without fusion, to treat degenerative lumbar stenosis. However, there are not many reports analyzing the clinical course after decompressive surgery of a single nerve root (the most symptomatic one) comparing it with decompression of all the roots in a segment. This study intends to compare the clinical course after decompressing the most symptomatic lumbar nerve root with the release of multiple lumbar nerve roots to relieve neuropathic pain resulting from degenerative lumbar stenosis. A prospective, observational, descriptive longitudinal study was performed. A total of 38 patients were divided into two groups that included each 19 cases. Patients underwent recalibration of either a single nerve root or multiple nerve roots of a segment. Percentages were calculated as well as the Student t test and the Pearson correlation. In group A, a decrease of 46.63 points was seen in the Oswestry scale, representing a 66.73% improvement in pain. In group B, in turn, a mean decrease of 34.54 points was seen in the Oswestry scale, equivalent to a 47.23% improvement in pain, with a Student t in which p = 0.11 and a Pearson correlation coefficient of 0.08. No statistically significant differences were found between both study groups.

  17. [Post-traumatic infraorbital nerve neuropathy].

    PubMed

    Sakavicius, Dalius; Kubilius, Ricardas; Sabalys, Gintautas

    2002-01-01

    The authors have investigated functional state of infraorbital nerve of 479 patients with zygomatic fractures. The degree of nerve damage was evaluated according to changes of pain threshold during damaged nerve stimulation. It was estimated that in 64.3% of zygomatic fractures the infraorbital nerve was affected. The nerve damage degree could be mild, moderate and severe. In 43.18% of moderate and severe nerve damage cases the neuropathy develops. The symptoms, signs and treatment of neuropathy have been described. The neuropathy with clinical symptoms as permanent soreness and paresthesias (itch, "running ant", fibrillations of cheek tissues etc.) in the infraorbital nerve innervation zone occur to 43.18% of the patients after moderate and severe damage of the nerve. The treatment of neuropathy was analysed. In cases of moderate and severe nerve damages, authors recommend to perform decompression of the nerve, because if not applied, the function of nerve does not recover.

  18. Core decompression for juvenile osteonecrosis.

    PubMed

    Herrera-Soto, José A; Price, Charles T

    2011-07-01

    Core decompression may be used as adjunct for treatment in some cases of Legg-Calvé-Perthes disease (LCPD). The primary application is for patients with onset at 12 years of age or older. We recommend classifying these older patients as idiopathic juvenile osteonecrosis and treating them similarly to adults with avascular necrosis. Juvenile osteonecrosis may benefit from core decompression combined with shelf acetabuloplasty during the early stages of necrosis. Younger children with LCPD may benefit from decompression by fenestration of the femoral head. Experience in adult-onset osteonecrosis and our early experience suggest that some patients may benefit from these adjunctive treatments. Copyright © 2011 Elsevier Inc. All rights reserved.

  19. A neurogenic tumor containing a low-grade malignant peripheral nerve sheath tumor (MPNST) component with loss of p16 expression and homozygous deletion of CDKN2A/p16: a case report showing progression from a neurofibroma to a high-grade MPNST.

    PubMed

    Tajima, Shogo; Koda, Kenji

    2015-01-01

    Development of malignant peripheral nerve sheath tumors (MPNSTs) is a stepwise process that involves the alteration of many cell cycle regulators and the double inactivation of the NF1 gene. Inactivation of the TP53 gene and deletion of the CDKN2A/p16 gene are known to play an important role in the process. Herein, we present a 19-year-old man with a familial history of neurofibromatosis type 1, in whom the tumor arose from the intercostal nerve and showed 3 components: a neurofibroma, a low-grade MPNST, and a high-grade MPNST. Loss of p16 expression and homozygous deletion of the CDKN2A/p16 gene were observed in both the low-grade and the high-grade MPNST. In contrast to low-grade MPNSTs, high-grade MPNSTs generally tend to lose expression of p16 and harbor homozygous deletion of the CDKN2A/p16 gene. Loss of p16 expression and homozygous deletion of the CDKN2A/p16 gene in low-grade MPNST in our case might be related to its progression to high-grade MPNST. To the best of our knowledge, this is the first study correlating the p16 expression status and CDKN2A/p16 gene alteration in low-grade MPNSTs.

  20. Supraclavicular nerve entrapment syndrome.

    PubMed

    Douchamps, Frédéric; Courtois, Anne-Catherine; Bruyère, Pierre-Julien; Crielaard, Jean-Michel

    2012-01-01

    Supraclavicular nerve entrapment syndrome, although rare, should be considered among the causes of anterior shoulder girdle pain. This syndrome is usually related to anatomic variants (involving the bone structures, fibrous bands, or muscles and tendons). Computed tomography is the most useful investigation. Medications used to treat neuropathic pain may provide relief. Otherwise, a local glucocorticoid injection or even surgical decompression should be considered. Copyright © 2011 Société française de rhumatologie. All rights reserved.

  1. Peripheral nerve surgery.

    PubMed

    McQuarrie, I G

    1985-05-01

    In treating the three main surgical problems of peripheral nerves--nerve sheath tumors, entrapment neuropathies, and acute nerve injuries--the overriding consideration is the preservation and restoration of neurologic function. Because of this, certain other principles may need to be compromised. These include achieving a gross total excision of benign tumors, employing conservative therapy as long as a disease process is not clearly progressing, and delaying repair of a nerve transection until the skin wound has healed. Only three pathophysiologic processes need be considered: neurapraxia (focal segmental dymyelination), axonotmesis (wallerian degeneration caused by a lesion that does not disrupt fascicles of nerve fibers), and neurotmesis (wallerian degeneration caused by a lesion that interrupts fascicles). With nerve sheath tumors and entrapment neuropathies, the goal is minimize the extent to which neurapraxia progresses to axonotmesis. The compressive force is relieved without carrying out internal neurolysis, a procedure that is poorly tolerated, presumably because a degree of nerve ischemia exists with any long-standing compression. When the nerve has sustained blunt trauma (through acute compression, percussion, or traction), the result can be a total loss of function and an extensive neuroma-in-continuity (scarring within the nerve). However, the neural pathophysiology may amount to nothing more than axonotmesis. Although this lesion, in time, leads to full and spontaneous recovery, it must be differentiated from the neuroma-in-continuity that contains disrupted fascicles requiring surgery. Finally, with open nerve transection, the priority is to match the fascicles of the proximal stump with those of the distal stump, a goal that is best achieved if primary neurorrhaphy is carried out.

  2. 21 CFR 884.5320 - Glans sheath.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... sheath. (a) Identification. A glans sheath device is a sheath which covers only the glans penis or part... the entire shaft of the penis. It is indicated only for the prevention of pregnancy and not for the...

  3. 21 CFR 884.5320 - Glans sheath.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... sheath. (a) Identification. A glans sheath device is a sheath which covers only the glans penis or part... the entire shaft of the penis. It is indicated only for the prevention of pregnancy and not for the...

  4. Outcomes and safety of endoscopic tarsal tunnel decompression: a systematic review.

    PubMed

    Gkotsoulias, Efthymios N; Simonson, Devin C; Roukis, Thomas S

    2014-02-01

    Open surgical decompression of the tarsal tunnel is the standard surgical approach for compression of the tibial nerve within the tarsal tunnel. Complications associated with this approach can be significant and periods of non-weight bearing are required. An alternative approach allowing for minimal soft tissue trauma and reduced time to ambulation is therefore desirable. Endoscopic tarsal tunnel decompression may provide such an alternative. The authors performed a systematic review of electronic databases and other relevant sources to identify material regarding the safety of endoscopic tarsal tunnel decompression. Only articles that included clear information concerning the safety of endoscopic tarsal tunnel decompression with a follow-up of at least 12 months were included. Three studies were identified involving 37 feet, with a weighted mean follow-up of 27 months. There were no permanent complications relating to iatrogenic nerve injury, deep infection, or prolonged wound healing problems documented despite initiating ambulation within one week of surgery. Two patients (5.6%) developed recurrence more than 2 years postoperative and one (2.7%) showed no improvement. Endoscopic tarsal tunnel decompression is a safe procedure with a low rate of recurrence or failure and allows for near-immediate ambulation. However, additional prospective investigations comparing open and endoscopic approaches to tarsal tunnel decompression are warranted.

  5. Sheaths: A Comparison of Magnetospheric, ICME, and Heliospheric Sheaths

    NASA Technical Reports Server (NTRS)

    Sibeck, D. G.; Richardson, J. D.; Liu, W.

    2007-01-01

    When a supersonic flow encounters an obstacles, shocks form to divert the flow around the obstacle. The region between the shock and the obstacle is the sheath, where the supersonic flow is compressed, heated, decelerated, and deflected. Supersonic flows, obstacles, and thus sheaths are observed on many scales throughout the Universe. We compare three examples seen in the heliosphere, illustrating the interaction of the solar wind with obstacles of three very different scales lengths. Magnetosheaths form behind planetary bow shocks on scales ranging from tens to 100 planetary radii. ICME sheath form behind shocks driven by solar disturbances on scale lengths of a few to tens of AU. The heliosheath forms behind the termination shock due to the obstacle presented by the interstellar medium on scale lengths of tens to a hundred AU. Despite this range in scales some common features have been observed. Magnetic holes, possibly due to mirror mode waves, have been observed in all three of these sheaths. Plasma depletion layers are observed in planetary and ICME sheaths. Other features observed in some sheaths are wave activity (ion cyclotron, plasma), energetic particles, transmission of Alfven waves/shocks, tangential discontinuities turbulence behind quasi-parallel shocks, standing slow mode waves, and reconnection on the obstacle boundary. We compare these sheath regions, discussing similarities and differences and how these may relate to the scale lengths of these regions.

  6. Nerve Degeneration and Regeneration Associated with NF1 Tumors

    DTIC Science & Technology

    2014-09-01

    the potential for nerve regeneration after PNST eradication. Additional aims will test photodynamic therapy as modality for eradication of PNST without...induced  nerve  regeneration  after   tumor  eradication.     Photodynamic   therapy  (PDT)  is  a  promising  modality...nerve graft implanted to bridge the gap and restore nerve continuity. 15. SUBJECT TERMS peripheral nerve sheath tumor, neurofibroma, photodynamic

  7. Two Portal Percutaneous Endoscopic Decompression for Lumbar Spinal Stenosis: Preliminary Study

    PubMed Central

    Dilokhuttakarn, Thitinut

    2016-01-01

    Study Design Retrospective. Purpose To report the outcomes of patients with lumbar spinal stenosis treated with percutaneous endoscopic decompression, focusing on the results of clinical evaluations. Overview of Literature There are no studies about two portal percutaneous endoscopic decompression in the treatment of lumbar spinal stenosis. Methods Medical and surgical complications were examined and clinical results were analyzed for 30 patients who consecutively underwent two portal percutaneous endoscopic decompression for lumbar spinal stenosis were reviewed. The operations were performed by unilateral laminotomy for bilateral decompression. Results All patients displayed clinical improvement when were evaluated with visual analog scale (VAS) score of pain, Oswestry disability index (ODI) and Macnab criteria. The improvement of VAS and ODI was 8.3±0.7 to 2.3±2.6 and 65.2±13.7 to 24.0±15.5, respectively (both p<0.05). Complications were the same as for open decompression. The most common complication was transient nerve root paresthesia. Conclusions Surgical decompression with two portal percutaneous endoscopic decompression has initial benefits, but long-term studies should pay more attention to the risks of postoperative instability and restenosis as well as the need for re-operation. Further investigations with long-term results are thus required. PMID:27114776

  8. Electromagnetic induction between axons and their schwann cell myelin-protein sheaths.

    PubMed

    Goodman, G; Bercovich, D

    2013-12-01

    Two concepts have long dominated vertebrate nerve electrophysiology: (a) Schwann cell-formed myelin sheaths separated by minute non-myelinated nodal gaps and spiraling around axons of peripheral motor nerves reduce current leakage during propagation of trains of axon action potentials; (b) "jumping" by action potentials between successive nodes greatly increases signal conduction velocity. Long-held and more recent assumptions and issues underlying those concepts have been obscured by research emphasis on axon-sheath biochemical symbiosis and nerve regeneration. We hypothesize: mutual electromagnetic induction in the axon-glial sheath association, is fundamental in signal conduction in peripheral and central myelinated axons, explains the g-ratio and is relevant to animal navigation.

  9. Laminated magnet field coil sheath

    DOEpatents

    Skaritka, J.R.

    1987-05-15

    A method for manufacturing a magnetic cable trim coil in a sheath assembly for use in a cryogenic particle accelerator. A precisely positioned pattern of trim coil turns is bonded to a flexible substrate sheath that is capable of withstanding cryogenic operating conditions. In the method of the invention the flexible substrate sheath, with the trim coil pattern precisely location relative to a bore tube assembly of an accelerator and is then bonded to the bore tube with a tape suitable for cryogenic application. The resultant assembly can be readily handled and installed within an iron magnet yoke assembly of a suitable cryogenic particle accelerator. 1 fig.

  10. Laminated magnet field coil sheath

    DOEpatents

    Skaritka, John R.

    1987-12-01

    a method for manufacturing a magnet cable trim coil in a sheath assembly for use in a cryogenic particle accelerator. A precisely positioned pattern of trim coil turns is bonded to a flexible substrate sheath that is capable of withstanding cryogenic operating conditions. In the method of the invention the flexible sheath, with the trim coil pattern precisely positioned thereon, is accurately positioned at a precise location relative to a bore tube assembly of an accelerator and is then bonded to the bore tube with a tape suitable for cryogenic application. The resultant assembly can be readily handled and installed within an iron magnet yoke assembly of a suitable cryogenic particle accelerator.

  11. Laminated magnet field coil sheath

    DOEpatents

    Skaritka, John R.

    1987-12-01

    a method for manufacturing a magnet cable trim coil in a sheath assembly for use in a cryogenic particle accelerator. A precisely positioned pattern of trim coil turns is bonded to a flexible substrate sheath that is capable of withstanding cryogenic operating conditions. In the method of the invention the flexible sheath, with the trim coil pattern precisely positioned thereon, is accurately positioned at a precise location relative to a bore tube assembly of an accelerator and is then bonded to the bore tube with a tape suitable for cryogenic application. The resultant assembly can be readily handled and installed within an iron magnet yoke assembly of a suitable cryogenic particle accelerator.

  12. Snare sheath versus evolution sheath in transvenous lead extraction.

    PubMed

    Kong, Jihua; Tian, Yilun; Guo, Fei; Ze, Feng; Duan, Jiangbo; Wang, Long; Li, Xuebin; Guo, Jihong

    2015-01-01

    Lead extraction remains a challenging procedure with significant success. Owing to the increasing use of cardiac implantable electronic devices, there is a growing need for effective techniques management, to avoid the occurrence of device-related complications and lead dysfunction. We made a comparison of Evolution sheath and Needles Eye Snare sheath (abbreviated to Snare sheath) by analyzed the results using two kind of the methods in the Cardiology Center of Peking University People's Hospital. In the retrospective study we evaluated patients who underwent lead extraction from July 2013 to July 2014. Those who underwent lead removal without using evolution or snare were excluded. Primary endpoints included total exposure time, operation time, and complications. Data on clinical characteristics, indications, and outcomes were prospectively collected and analyzed. A total of 76 patients were included in the study (65.8% male; aged 68.1±14.34 years old). Snare and Evolution were used in 59 and 17 patients, respectively. A total of 134 leads were removed with 103 leads (76.87%) extracted using the Snare sheath. Lead age was 10.8±7.0 years. Complete extraction was observed in 67 patients of 124 leads. Evolution sheath was associated with significantly lower complication even after adjustment of the number of leads, type of leads, and lead age, compared to the Snare group (P<0.05). In the Snare sheath group, mortality rate was 1.69% and minor complication rate was 3.39%. When compared to the Snare sheath, lead extraction with the Evolution sheath has less X-ray exposure time and less operation time (P<0.05), while with a higher success rate (P<0.05). Besides, the Evolution group has fewer major and minor complications.

  13. Commentary: the sedimentation sign: correlation with operative level in patients undergoing lumbar decompression for spinal stenosis.

    PubMed

    Khanna, A Jay

    2013-08-01

    Fazal A, Yoo A, Bendo JA. Does the presence of the nerve root sedimentation sign on MRI correlate with the operative level in patients undergoing posterior lumbar decompression for lumbar stenosis? Spine J 2013;13:837-42 (in this issue). Copyright © 2013 Elsevier Inc. All rights reserved.

  14. A Start Toward Micronucleus-Based Decompression Models; Altitude Decompression

    NASA Technical Reports Server (NTRS)

    Van Liew, H. D.; Conkin, Johnny

    2007-01-01

    Do gaseous micronuclei trigger the formation of bubbles in decompression sickness (DCS)? Most previous instructions for DCS prevention have been oriented toward supersaturated gas in tissue. We are developing a mathematical model that is oriented toward the expected behavior of micronuclei. The issue is simplified in altitude decompressions because the aviator or astronaut is exposed only to decompression, whereas in diving there is a compression before the decompression. The model deals with four variables: duration of breathing of 100% oxygen before going to altitude (O2 prebreathing), altitude of the exposure, exposure duration, and rate of ascent. Assumptions: a) there is a population of micronuclei of various sizes having a range of characteristics, b) micronuclei are stable until they grow to a certain critical nucleation radius, c) it takes time for gas to diffuse in or out of micronuclei, and d) all other variables being equal, growth of micronuclei upon decompression is more rapid at high altitude because of the rarified gas in the micronuclei. To estimate parameters, we use a dataset of 4,756 men in altitude chambers exposed to various combinations of the model s variables. The model predicts occurrence of DCS symptoms quite well. It is notable that both the altitude chamber data and the model show little effect of O2 prebreathing until it lasts more than 60 minutes; this is in contrast to a conventional idea that the benefit of prebreathing is directly due to exponential washout of tissue nitrogen. The delay in response to O2 prebreathing can be interpreted as time required for outward diffusion of nitrogen; when the micronuclei become small enough, they are disabled, either by crushing or because they cannot expand to a critical nucleation size when the subject ascends to altitude.

  15. Osteoplastic decompressive craniotomy--an alternative to decompressive craniectomy.

    PubMed

    Mracek, Jan; Choc, Milan; Mork, Jan; Vacek, Petr; Mracek, Zdenek

    2011-11-01

    In spite of various degrees of brain expansion, decompressive surgery is usually carried out using decompressive craniectomy (DC). After craniectomy it is necessary to perform cranioplasty, which prolongs hospitalization and is not always without complications. Hence, in situations when cranial decompression is indicated, but DC would be too radical, we do not remove the bone flap, and we perform so-called osteoplastic decompressive craniotomy (ODC). The technique is detailed. To demonstrate the effectiveness of ODC. Twenty patients underwent ODC for brain edema under various pathological conditions. The diagnoses were as follows: 13 subdural hematomas, 3 cerebral contusions, 2 middle cerebral artery infarcts, 1 epidural hematoma and 1 arteriovenous malformation. The effect of ODC was assessed using postoperative ICP monitoring and the midline shift on CT. The ICP threshold for the additional removal of the bone flap was 25 mmHg. Clinical outcome was evaluated 6 months after surgery using the Glasgow Outcome Scale (GOS). Postoperative ICP was up to 25 mmHg in 18 patients and exceeded 25 mmHg in 2 cases. The mean midline shift on CT was 10 mm preoperatively and 3 mm postoperatively. The decompression during ODC was sufficient in 18 patients and insufficient in 2 in whom an additional removal of the bone flap was performed. Eight survivals had a favorable outcome (GOS 4-5); 12 patients had an unfavorable outcome (GOS 1-3), and of these, 4 died. Our limited study shows that ODC is effective in the treatment of intracranial hypertension in the selected subgroup of patients in whom DC would be too radical. The main advantage of this method is the elimination of further cranioplasty.

  16. COMPUTERIZED EXPERT SYSTEM FOR EVALUATION OF AUTOMATED VISUAL FIELDS FROM THE ISCHEMIC OPTIC NEUROPATHY DECOMPRESSION TRIAL: METHODS, BASELINE FIELDS, AND SIX-MONTH LONGITUDINAL FOLLOW-UP

    PubMed Central

    Feldon, Steven E

    2004-01-01

    ABSTRACT Purpose To validate a computerized expert system evaluating visual fields in a prospective clinical trial, the Ischemic Optic Neuropathy Decompression Trial (IONDT). To identify the pattern and within-pattern severity of field defects for study eyes at baseline and 6-month follow-up. Design Humphrey visual field (HVF) change was used as the outcome measure for a prospective, randomized, multi-center trial to test the null hypothesis that optic nerve sheath decompression was ineffective in treating nonarteritic anterior ischemic optic neuropathy and to ascertain the natural history of the disease. Methods An expert panel established criteria for the type and severity of visual field defects. Using these criteria, a rule-based computerized expert system interpreted HVF from baseline and 6-month visits for patients randomized to surgery or careful follow-up and for patients who were not randomized. Results A computerized expert system was devised and validated. The system was then used to analyze HVFs. The pattern of defects found at baseline for patients randomized to surgery did not differ from that of patients randomized to careful follow-up. The most common pattern of defect was a superior and inferior arcuate with central scotoma for randomized eyes (19.2%) and a superior and inferior arcuate for nonrandomized eyes (30.6%). Field patterns at 6 months and baseline were not different. For randomized study eyes, the superior altitudinal defects improved (P = .03), as did the inferior altitudinal defects (P = .01). For nonrandomized study eyes, only the inferior altitudinal defects improved (P = .02). No treatment effect was noted. Conclusions A novel rule-based expert system successfully interpreted visual field defects at baseline of eyes enrolled in the IONDT. PMID:15747764

  17. FURTHER OBSERVATIONS ON THE STRUCTURE OF MYELIN SHEATHS IN THE CENTRAL NERVOUS SYSTEM

    PubMed Central

    Peters, A.

    1964-01-01

    Direct evidence has been presented to confirm the existence of a spiral in the myelin sheaths of the central nervous system. An account of some of the variations in structure of central myelin sheaths has been given and it has been shown that the radial component of myelin sheaths has the form of a series of rod-like thickenings of the intraperiod line. These thickenings extend along the intraperiod line in a direction parallel to the length of the axon. The relative position of the internal mesaxon and external tongue of cytoplasm has been determined in a number of transverse sections of sheaths from the optic nerves of adult mice, adult rats, and young rats. In about 75 per cent of the mature sheaths examined, these two structures were found within the same quadrant of the sheath, so that the cytoplasm of the external tongue process tends to lie directly outside that associated with the internal mesaxon. The frequency with which the internal mesaxon and external tongue lie within the same quadrant of the sheath increases both with the age of the animal and with the number of lamellae present within a sheath. The possible significance of these findings is discussed. PMID:14126873

  18. Decompressive craniectomy with lattice duraplasty.

    PubMed

    Mitchell, P; Tseng, M; Mendelow, A D

    2004-02-01

    A method of opening dura for decompressive craniectomies is described. Numerous cuts intersecting in a lattice pattern allow the dura to expand in a gradual and controlled manner minimising the chances of cortical laceration or venous kinking on the craniectomy edge.

  19. Decompression sickness during saturation dives.

    PubMed

    Berghage, T E

    1976-12-01

    Available Navy saturation diving data were analyzed for an evaluation of the therapeutic adequacy of decompression sickness treatment procedures and for delineation of precipitant factors in the etiology and treatment of decompression sickness during saturation dives. None of the cases of decompression sickness recorded during saturation dives involved more than musculoskeletal or joint pain, and in 96% of the cases the joint pain was confined to the diver's knees. In 89% of the cases symptoms appeared while the divers were still under pressure. The subsequent recompression treatment of these cases resulted in full relief in only 35% of the cases; the remaining 65% completed the therapy and subsequent decompression with residual pain which diminished over a period of weeks. The adequacy of the recompression appears to be inversely proportional to the depth of reported onset of symptoms and the time required to obtain even partial relief is directly related to the magnitude of the recompression ratio used. Four explanations are suggested for the limited recompression therapy common in saturation diving: increase in musculoskeletal pain with recompression, peer pressure to avoid extension of the chamber confinement, lack of severe neurological symptoms, and the tremendous depths required to obtain a reasonable recompression ratio. The author further suggests that future treatment procedures will require a departure from the accepted concept of radically decreasing the volume of inert gas bubbles by increasing pressure.

  20. Failed subacromial decompression. Risk factors.

    PubMed

    Bouchard, A; Garret, J; Favard, L; Charles, H; Ollat, D

    2014-12-01

    Arthroscopic subacromial decompression (acromioplasty) is widely held to be effective, although pain may persist after the procedure. The objective of this study was to evaluate the proportion of patients with residual pain (i.e., the failure rate) after isolated subacromial decompression and to look for predictors of failure. We conducted a retrospective multicentre study of 108 patients managed with isolated arthroscopic subacromial decompression between 2007 and 2011, for any reason. We excluded patients in whom surgical procedures on the rotator cuff tendons were performed concomitantly. Data were collected from the medical records, a telephone questionnaire, and radiographs obtained before surgery and at last follow-up. Failure was defined as persistent pain (visual analogue scale score>3) more than 6 months after surgery and at last follow-up. The failure rate was 29% (31/108). Two factors significantly predicted failure, namely, receiving workers' compensation benefits for the shoulder condition and co-planing. Heterogeneous calcific tendinopathy and deep partial-thickness rotator cuff tears were also associated with poorer outcomes, but the effect was not statistically significant. Co-planing may predict failure of subacromial decompression, although whether this effect is due to an insufficient degree of co-planing or to the technique itself is unclear. Nevertheless, in patients with symptoms from the acromio-clavicular joint, acromio-clavicular resection is probably the best option. Receiving workers' compensation benefits was also associated with treatment failure, as a result of well-known parameters related to the social welfare system. Isolated arthroscopic subacromial decompression is effective in 70% of cases. We recommend the utmost caution if co-planing is considered and/or the patient receives workers' compensation benefits for the shoulder condition, as these two factors are associated with a significant increase in the failure rate. IV

  1. Microparticles generated by decompression stress cause central nervous system injury manifested as neurohypophysial terminal action potential broadening

    PubMed Central

    Yang, Ming; Kosterin, Paul; Salzberg, Brian M.; Milovanova, Tatyana N.; Bhopale, Veena M.

    2013-01-01

    The study goal was to use membrane voltage changes during neurohypophysial action potential (AP) propagation as an index of nerve function to evaluate the role that circulating microparticles (MPs) play in causing central nervous system injury in response to decompression stress in a murine model. Mice studied 1 h following decompression from 790 kPa air pressure for 2 h exhibit a 45% broadening of the neurohypophysial AP. Broadening did not occur if mice were injected with the MP lytic agent polyethylene glycol telomere B immediately after decompression, were rendered thrombocytopenic, or were treated with an inhibitor of nitric oxide synthase-2 (iNOS) prior to decompression, or in knockout (KO) mice lacking myeloperoxidase or iNOS. If MPs were harvested from control (no decompression) mice and injected into naive mice, no AP broadening occurred, but AP broadening was observed with injections of equal numbers of MPs from either wild-type or iNOS KO mice subjected to decompression stress. Although not required for AP broadening, MPs from decompressed mice, but not control mice, exhibit NADPH oxidase activation. We conclude that inherent differences in MPs from decompressed mice, rather than elevated MPs numbers, mediate neurological injury and that a component of the perivascular response to MPs involves iNOS. Additional study is needed to determine the mechanism of AP broadening and also mechanisms for MP generation associated with exposure to elevated gas pressure. PMID:24052032

  2. Microparticles generated by decompression stress cause central nervous system injury manifested as neurohypophysial terminal action potential broadening.

    PubMed

    Yang, Ming; Kosterin, Paul; Salzberg, Brian M; Milovanova, Tatyana N; Bhopale, Veena M; Thom, Stephen R

    2013-11-01

    The study goal was to use membrane voltage changes during neurohypophysial action potential (AP) propagation as an index of nerve function to evaluate the role that circulating microparticles (MPs) play in causing central nervous system injury in response to decompression stress in a murine model. Mice studied 1 h following decompression from 790 kPa air pressure for 2 h exhibit a 45% broadening of the neurohypophysial AP. Broadening did not occur if mice were injected with the MP lytic agent polyethylene glycol telomere B immediately after decompression, were rendered thrombocytopenic, or were treated with an inhibitor of nitric oxide synthase-2 (iNOS) prior to decompression, or in knockout (KO) mice lacking myeloperoxidase or iNOS. If MPs were harvested from control (no decompression) mice and injected into naive mice, no AP broadening occurred, but AP broadening was observed with injections of equal numbers of MPs from either wild-type or iNOS KO mice subjected to decompression stress. Although not required for AP broadening, MPs from decompressed mice, but not control mice, exhibit NADPH oxidase activation. We conclude that inherent differences in MPs from decompressed mice, rather than elevated MPs numbers, mediate neurological injury and that a component of the perivascular response to MPs involves iNOS. Additional study is needed to determine the mechanism of AP broadening and also mechanisms for MP generation associated with exposure to elevated gas pressure.

  3. Dust in the magnetized sheath

    SciTech Connect

    Pandey, B. P.; Samarian, A.; Vladimirov, S. V.

    2007-09-15

    In the present work the structure of the magnetized sheath is investigated in the multifluid framework. The ambient magnetic field is assumed parallel to the wall and the effect of the plasma magnetization, plasma ionization, and plasma-neutral collisions on the sheath is examined. It is shown that the width of the non-neutral boundary layer is dependent on the collision frequencies as well as on the plasma magnetization. The size of the sheath layer can decrease with the increase in magnetic field. The increase in the ion-neutral collision can also adversely affect the sheath size. The equilibrium and levitation of the dust particles in a collisional magnetized sheath are shown to depend on the collision frequencies and on the magnetization. Further, the increase in the collision or magnetization invariably leads to the presence of the positively charged grains near the plasma wall suggesting that the grain levitation inside the charged layer is implicitly dependent on the plasma parameters in a nontrivial way.

  4. Dysphonia and dysphagia after anterior cervical decompression.

    PubMed

    Tervonen, Hanna; Niemelä, Mika; Lauri, Eija-Riitta; Back, Leif; Juvas, Anja; Räsänen, Pirjo; Roine, Risto P; Sintonen, Harri; Salmi, Tapani; Vilkman, S Erkki; Aaltonen, Leena-Maija

    2007-08-01

    In this paper, the authors investigate the effects of anterior cervical decompression (ACD) on swallowing and vocal function. The study comprised 114 patients who underwent ACD. The early group (50 patients) was examined immediately pre- and postoperatively, and the late group (64 patients) was examined at only 3 to 9 months postoperatively. Fifty age- and sex-matched patients from the Department of Otorhinolaryngology-Head and Neck Surgery who had not been intubated in the previous 5 years were used as a control group. All patients in the early and control groups were examined by a laryngologist; patients in the late group were examined by a laryngologist and a neurosurgeon. Videolaryngostroboscopy was performed in all members of the patient and control groups, and the function of the ninth through 12th cranial nerves were clinically evaluated. Data were collected concerning swallowing, voice quality, surgery results, and health-related quality of life. Patients with persistent dysphonia were referred for phoniatric evaluation and laryngeal electromyography (EMG). Those with persistent dysphagia underwent transoral endoscopic evaluation of swallowing function and videofluorography. Sixty percent of patients in the early group reported dysphonia and 69% reported dysphagia at the immediate postoperative visit. Unilateral vocal fold paresis occurred in 12%. The prevalence of both dysphonia and dysphagia decreased in both groups 3 to 9 months postoperatively. All six patients with vocal fold paresis in the early group recovered, and in the late group there were two cases of vocal fold paresis. The results of laryngeal EMG were abnormal in 14 of 16 patients with persistent dysphonia. Neither intraoperative factors nor age or sex had any effect on the occurrence of dysphonia, dysphagia, or vocal fold paresis. Most patients were satisfied with the surgical outcome. Dysphonia, dysphagia, and vocal fold paresis are common but usually transient complications of ACD

  5. Spaceflight Decompression Sickness Contingency Plan

    NASA Technical Reports Server (NTRS)

    Dervay, Joseph P.

    2007-01-01

    A viewgraph presentation on the Decompression Sickness (DCS) Contingency Plan for manned spaceflight is shown. The topics include: 1) Approach; 2) DCS Contingency Plan Overview; 3) Extravehicular Activity (EVA) Cuff Classifications; 4) On-orbit Treatment Philosophy; 5) Long Form Malfunction Procedure (MAL); 6) Medical Checklist; 7) Flight Rules; 8) Crew Training; 9) Flight Surgeon / Biomedical Engineer (BME) Training; and 10) DCS Emergency Landing Site.

  6. Cardiopulmonary Changes with Moderate Decompression in Rats

    NASA Technical Reports Server (NTRS)

    Robinson, R.; Little, T.; Doursout, M.-F.; Butler, B. D.; Chelly, J. E.

    1996-01-01

    Sprague-Dawley rats were compressed to 616 kPa for 120 min then decompressed at 38 kPa/min to assess the cardiovascular and pulmonary responses to moderate decompression stress. In one series of experiments the rats were chronically instrumented with Doppler ultrasonic probes for simultaneous measurement of blood pressure, cardiac output, heart rate, left and right ventricular wall thickening fraction, and venous bubble detection. Data were collected at base-line, throughout the compression/decompression protocol, and for 120 min post decompression. In a second series of experiments the pulmonary responses to the decompression protocol were evaluated in non-instrumented rats. Analyses included blood gases, pleural and bronchoalveolar lavage (BAL) protein and hemoglobin concentration, pulmonary edema, BAL and lung tissue phospholipids, lung compliance, and cell counts. Venous bubbles were directly observed in 90% of the rats where immediate post-decompression autopsy was performed and in 37% using implanted Doppler monitors. Cardiac output, stroke volume, and right ventricular wall thickening fractions were significantly decreased post decompression, whereas systemic vascular resistance was increased suggesting a decrease in venous return. BAL Hb and total protein levels were increased 0 and 60 min post decompression, pleural and plasma levels were unchanged. BAL white blood cells and neutrophil percentages were increased 0 and 60 min post decompression and pulmonary edema was detected. Venous bubbles produced with moderate decompression profiles give detectable cardiovascular and pulmonary responses in the rat.

  7. European EVA decompression sickness risks

    NASA Astrophysics Data System (ADS)

    Vogt, Lorenz; Wenzel, Jürgen; Skoog, A. I.; Luck, S.; Svensson, Bengt

    For the first manned flight of Hermes there will be a capability of performing EVA. The European EVA Space Suit will be an anthropomorphic system with an internal pressure of 500 hPa of pure oxygen. The pressure reduction from the Hermes cabin pressure of 1013 hPa will induce a risk for Decompression Sickness (DCS) for the EVA crewmember if no adequate protective procedures are implemented. Specific decompression procedures have to be developed. From a critical review of the literature and by using knowledge gained from research conducted in the past in the fields of diving and aerospace medicine safe protective procedures are proposed for the European EVA scenario. An R factor of 1.2 and a tissue half-time ( t1/2) of 360 minutes in a single-tissue model have been identified as appropriate operational values. On the basis of an acceptable risk level of approximately 1%, oxygen prebreathing times are proposed for (a) direct pressure reduction from 1013 hPa to a suit pressure of 500 hPa, and (b) staged decompression using a 700 hPa intermediate stage in the spacecraft cabin. In addition, factors which influence individual susceptibility to DCS are identified. Recommendations are also given in the areas of crew selection and medical monitoring requirements together with therapeutic measures that can be implemented in the Hermes scenario. A method for demonstration of the validity of proposed risks and procedures is proposed.

  8. [Severe decompression sickness in divers].

    PubMed

    Beuster, W; van Laak, U

    1999-01-01

    The term "decompression illness (DCI)" is a disorder which arises from the presence of ectopic gas bubbles following decompression. Scuba diving poses the risk of two typically clinical syndromes: decompression sickness (DCS) and arterial gas embolism (AGE). DCS results from the formation of gas bubbles in the tissues of the body and in the blood due to rapid reduction of the environmental pressure. AGE is caused by pulmonary overinflation if the breathing gas cannot be exhaled adequately during the ascent. Although the pathophysiological mechanisms of these two disorders are quite different, both of them lead to the same result: inert gas bubbles that may cause impairment of vital functions due to hypoxia. Recognizing the signs and symptoms of DCI is the first step of the therapy. The emergency treatment contains: basic life support, advanced life support--if necessary, horizontal positioning of the victim, administration of 100% normobaric oxygen via face mask or endotracheal tube, rehydration, rapid transportation to the nearest emergency department/hyperbaric facility for definitive treatment in order to prevent serious neurological sequelae.

  9. Postoperative Analgesia Using Psoas Sheath Block Versus Three-in-One Block in Anterior Cruciate Ligament Reconstruction

    DTIC Science & Technology

    1999-10-01

    were blocked and two cases where all nerves were blocked. Key Words: Regional Anesthesia; Lumbar Plexus Block, Postoperative Pain Management; Pre...and sciatic(Lumbar4-Sacral3). A "psoas sheath block" and a "three-in-one block" are two techniques used to block the lumbar plexus from which the...nerve blockade Operational definition. A regional anesthetic technique used to block transmission of the nerves of the lumbar plexus including the

  10. Progress on Quantitative Modeling of rf Sheaths

    NASA Astrophysics Data System (ADS)

    D'Ippolito, D. A.; Myra, J. R.; Kohno, H.; Wright, J. C.

    2011-12-01

    A new quantitative approach for computing the rf sheath potential is described, which incorporates plasma dielectric effects and the relative geometry of the magnetic field and the material boundaries. The new approach uses a modified boundary condition ("rf sheath BC") that couples the rf waves and the sheaths at the boundary. It treats the sheath as a thin vacuum region and matches the fields across the plasma-vacuum boundary. When combined with the Child-Langmuir Law (relating the sheath width and sheath potential), the model permits a self-consistent determination of the sheath parameters and the rf electric field at the sheath-plasma boundary. Semi-analytic models using this BC predict a number of general features, including a sheath voltage threshold, a dimensionless parameter characterizing rf sheath effects, and the existence of sheath plasma waves with an associated resonance. Since the sheath BC is nonlinear and dependent on geometry, computing the sheath potential numerically is a challenging computational problem. Numerical results will be presented from a new parallel-processing finite-element rf wave code for the tokamak scrape-off layer (called "rfSOL"). The code has verified the physics predicted by analytic theory in 1D, and extended the solutions into model 2D geometries. The numerical calculations confirm the existence of multiple roots and hysteresis effects, and parameter studies have been carried out. Areas for future work will be discussed.

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

    PubMed Central

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

    2013-01-01

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

  12. Relationship between myelin sheath diameter and internodal length in axons of the anterior medullary velum of the adult rat.

    PubMed

    Ibrahim, M; Butt, A M; Berry, M

    1995-11-01

    Relations between myelin sheath diameters and internodal lengths were measured in whole mounts of osmium stained intact anterior medullary velum (AMV) from glutaraldehyde perfused adult rats. The AMV is a sheet of CNS tissue which roofs the IVth ventricle and contains fascicles of myelinated fibres which arise mainly from the nucleus of the IVth cranial nerve. These fibers displayed a broad range of myelin sheath external diameters and internodal lengths, from < 1-12 microns and 50-750 microns, respectively. Myelin sheath external diameter was a measurement of the axonal diameter plus the thickness of its myelin sheath, while internodal length was measured as the distance between consecutive nodes. There was a broadly linear relationship between myelin sheath diameters and internodal lengths, with the smaller diameter sheaths tending to have shorter internodes than the larger. However, the correlation was weak and for any given diameter myelin sheaths displayed considerable variation in their internodal lengths. The smallest diameter myelin sheaths, < 4 microns, consistently had shorter internodes than predicted by a linear regression and, in an analysis of consecutive internodes in single fibres, the slope was flattened in fibres with a diameter > 4 microns. Our results indicated that small and large calibre fibres may have different myelin sheath diameter-internodal length interrelations.

  13. Hemilingual spasm: defining a new entity, its electrophysiological correlates and surgical treatment through microvascular decompression.

    PubMed

    Osburn, Leisha L; Møller, Aage R; Bhatt, Jay R; Cohen-Gadol, Aaron A

    2010-07-01

    We report on vascular compression syndrome of the 12th cranial nerve (hypoglossal), an occurrence not previously reported, and demonstrate, through corresponding objective electrophysiological evidence, that microvascular decompression of the hypoglossal nerve root can cure hemilingual spasm. A 52-year-old man had lower face muscle twitching and tongue spasms, which worsened with talking, chewing, or emotional stress. Carbamazepine offered only temporary relief, and relief from injections of botulinum toxin was insignificant. He was referred for surgical treatment. High-resolution magnetic resonance imaging of his posterior fossa contents revealed no obvious evidence of any compressive vessel along the facial nerve, but a compressive vessel along the hypoglossal nerve was apparent. The presence of preoperative tongue spasms encouraged interoperative monitoring of tongue motor responses. The facial nerve exit zone was explored, but microsurgical inspection of the seventh/eighth cranial nerve complex did not reveal any compressive vessel. However, at the anterolateral aspect of the medulla oblongata, the hypoglossal nerve was clearly compressed and distorted laterally by a large tortuous vertebral artery. When the artery was mobilized away from the nerve, the abnormal late electromyographic response to transcranial electrical stimulation disappeared; immediately after shredded Teflon was interpositioned between the artery and the nerve, the abnormal spontaneous tongue fasciculation also disappeared. The patient has remained spasm free 6 months after surgery. Hemilingual spasm may be caused by vascular contact/compression along cranial nerve XII at the lower brainstem and belong to the same family of cranial nerve hyperactivity disorders as hemifacial spasm.

  14. Radiation therapy for primary optic nerve meningiomas.

    PubMed

    Smith, J L; Vuksanovic, M M; Yates, B M; Bienfang, D C

    1981-06-01

    Optic nerve sheath meningiomas, formerly thought to be rare, have been encountered with surprising frequency since the widespread use of computed tomography. Early diagnosis led to an enthusiastic surgical approach to these lesions, but this has been tempered by the realization that even in the best of hands, blindness followed such surgery with distressing frequency. Optic nerve sheath meningiomas may be divided into primary, secondary, and multiple meningioma groups. Five patients with primary optic nerve sheath meningiomas treated with irradiation therapy are presented in this report. Improvement in visual acuity, stabilization to increase in the visual field, and decrease in size to total regression of optociliary veins, have been documented following irradiation therapy of the posterior orbital and intracanalicular portions of the optic nerve in some of these cases. Although each patient must be carefully individualized, there is no question that visual palliation can be achieved in some cases of optic nerve sheath meningioma. Further investigation of this therapeutic modality in selected cases in advised.

  15. Thoracic needle decompression for tension pneumothorax: clinical correlation with catheter length

    PubMed Central

    Ball, Chad G.; Wyrzykowski, Amy D.; Kirkpatrick, Andrew W.; Dente, Christopher J.; Nicholas, Jeffrey M.; Salomone, Jeffrey P.; Rozycki, Grace S.; Kortbeek, John B.; Feliciano, David V.

    2010-01-01

    Background Tension pneumothorax requires emergent decompression. Unfortunately, some needle thoracostomies (NTs) are unsuccessful because of insufficient catheter length. All previous studies have used thickness of the chest wall (based on cadaver studies, ultrasonography or computed tomography [CT]) to extrapolate probable catheter effectiveness. The objective of this clinical study was to identify the frequency of NT failure with various catheter lengths. Methods We evaluated the records of all patients with severe blunt injury who had a prehospital NT before arrival at a level-1 trauma centre over a 48-month period. Patients were divided into 2 groups: helicopter (4.5-cm catheter sheath) and ground ambulance (3.2 cm) transport. Success of the NT was confirmed by the absence of a large pneumothorax on subsequent thoracic ultrasonography and CT. Results Needle thoracostomy decompression was attempted in 1.5% (142/9689) of patients. Among patients with blunt injuries, the incidence was 1.4% (101/7073). Patients transported by helicopter (74%) received a 4.5-cm sheath. The remainder (26% ground transport) received a 3.2-cm catheter. A minority in each group (helicopter 15%, ground 28%) underwent immediate chest tube insertion (before thoracic ultrasound) because of ongoing hemodynamic instability. Failure to decompress the pleural space by NT was observed via ultrasound and/or CT in 65% (17/26) of attempts with a 3.2-cm catheter, compared with only 4% (3/75) of attempts with a 4.5-cm catheter (p < 0.001). Conclusion Tension pneumothorax decompression using a 3.2-cm catheter was unsuccessful in up to 65% of cases. When a larger 4.5-cm catheter was used, fewer procedures (4%) failed. Thoracic ultrasonography can be used to confirm NT placement. PMID:20507791

  16. Nerve Regeneration in the Peripheral Nervous System versus the Central Nervous System and the Relevance to Speech and Hearing after Nerve Injuries

    ERIC Educational Resources Information Center

    Gordon, Tessa; Gordon, Karen

    2010-01-01

    Schwann cells normally form myelin sheaths around axons in the peripheral nervous system (PNS) and support nerve regeneration after nerve injury. In contrast, nerve regeneration in the central nervous system (CNS) is not supported by the myelinating cells known as oligodendrocytes. We have found that: 1) low frequency electrical stimulation can be…

  17. Nerve Regeneration in the Peripheral Nervous System versus the Central Nervous System and the Relevance to Speech and Hearing after Nerve Injuries

    ERIC Educational Resources Information Center

    Gordon, Tessa; Gordon, Karen

    2010-01-01

    Schwann cells normally form myelin sheaths around axons in the peripheral nervous system (PNS) and support nerve regeneration after nerve injury. In contrast, nerve regeneration in the central nervous system (CNS) is not supported by the myelinating cells known as oligodendrocytes. We have found that: 1) low frequency electrical stimulation can be…

  18. Sheath-in-Sheath Technique for Exteriorization of Body Floss Wire.

    PubMed

    Pua, Uei

    2017-05-01

    In this technique, we describe the insertion of a second sheath into the primary sheath containing a guidewire that is meant to be exteriorized. The second sheath serves to open the valve of the primary sheath and creates a water-tight chamber for the guidewire to enter. The second sheath is then removed, exposing the successfully exteriorized guidewire. This technique is an useful adjunct to conventional guidewire exteriorization techniques during body floss procedures. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Thalmann Algorithm Decompression Table Generation Software Design Document

    DTIC Science & Technology

    2010-09-01

    Decompression Table Generation Software Design Document Navy Experimental Diving Unit Author...TITLE (Include Security Classification) (U) THALMANN ALGORITHM DECOMPRESSION TABLE GENERATION SOFTWARE DESIGN DOCUMENT 12. PERSONAL AUTHOR(S...1 2. Decompression Table Generator (TBLP7R

  20. Nerve conduction and electromyography studies.

    PubMed

    Kane, N M; Oware, A

    2012-07-01

    Nerve conduction studies (NCS) and electromyography (EMG), often shortened to 'EMGs', are a useful adjunct to clinical examination of the peripheral nervous system and striated skeletal muscle. NCS provide an efficient and rapid method of quantifying nerve conduction velocity (CV) and the amplitude of both sensory nerve action potentials (SNAPs) and compound motor action potentials (cMAPs). The CV reflects speed of propagation of action potentials, by saltatory conduction, along large myelinated axons in a peripheral nerve. The amplitude of SNAPs is in part determined by the number of axons in a sensory nerve, whilst amplitude of cMAPs reflects integrated function of the motor axons, neuromuscular junction and striated muscle. Repetitive nerve stimulation (RNS) can identify defects of neuromuscular junction (NMJ) transmission, pre- or post-synaptic. Needle EMG examination can detect myopathic changes in muscle and signs of denervation. Combinations of these procedures can establish if motor and/or sensory nerve cell bodies or peripheral nerves are damaged (e.g. motor neuronopathy, sensory ganglionopathy or neuropathy), and also indicate if the primary target is the axon or the myelin sheath (i.e. axonal or demyelinating neuropathies). The distribution of nerve damage can be determined as either generalised, multifocal (mononeuropathy multiplex) or focal. The latter often due to compression at the common entrapment sites (such as the carpal tunnel, Guyon's canal, cubital tunnel, radial groove, fibular head and tarsal tunnel, to name but a few of the reported hundred or so 'entrapment neuropathies').

  1. Surgical Decompression in the Treatment of Diabetic Peripheral Neuropathy: A Systematic Review and Meta-analysis.

    PubMed

    Tu, Yiji; Lineaweaver, William Charles; Chen, Zenggan; Hu, Junda; Mullins, Fred; Zhang, Feng

    2017-03-01

    Background Over the last decade, surgical decompression procedures have been commonly used in the treatment of diabetic peripheral neuropathy. However, the effectiveness of them remains to be proved. Methods A comprehensive literature search of databases including PubMed-Medline, Ovid-EMBASE, and Cochrane Library was performed to collect the related literatures. The Medical Subject Headings used were "diabetic neuropathy," "surgical decompression," and "outcomes." The methodological index for nonrandomized studies was adopted for assessing the studies included in this review. Analyses were performed with Review Manager (Version 5.3, Copenhagen: The Nordic Cochrane Centre, the Cochrane Collaboration, 2014). Results A total of 12 literatures (including 8 prospective and 4 retrospective) encompassing 1,825 patients with DPN were included in the final analysis. Only one literature was identified as a randomized controlled trial. The remaining 11 literatures were observational studies; 7 of them were classified as upper-extremity nerve decompression group and 4 of them were classified as lower-extremity nerve decompression group. Meta-analysis shows that Boston questionnaire symptom severity and functional status of upper extremities, and distal motor latency and sensory conduction velocity of median nerve of DPN patients are significantly improved after carpal tunnel release. Besides, visual analog scale and two-point discrimination are considered clinically and statistically significant in lower extremities after operation. Conclusions The findings from our review have shown the efficacy of surgical decompression procedures in relieving the neurologic symptoms and restoring the sensory deficits in DPN patients. As there are few high-quality randomized controlled trials or well-designed prospective studies, more data are needed to elucidate the role of surgical procedures for DPN treatment in the future.

  2. Neuromas of the calcaneal nerves.

    PubMed

    Kim, J; Dellon, A L

    2001-11-01

    A neuroma of a calcaneal nerve has never been reported. A series of 15 patients with heel pain due to a neuroma of a calcaneal nerve are reviewed. These patients previously had either a plantar fasciotomy (n = 4), calcaneal spur removal (n = 2), ankle fusion (n = 2), or tarsal tunnel decompression (n = 7). Neuromas occurred on calcaneal branches that arose from either the posterior tibial nerve (n = 1), lateral plantar nerve (n = 1), the medial plantar nerve (n = 9), or more than one of these nerves (n = 4). Operative approach was through an extended tarsal tunnel incision to permit identification of all calcaneal nerves. The neuroma was resected and implanted into the flexor hallucis longus muscle. Excellent relief of pain occurred in 60%, and good relief in 33%. One patient (17%) had no improvement and required resection of the lateral plantar nerve. Awareness that the heel may be innervated by multiple calcaneal branches suggests that surgery for heel pain of neural origin employ a surgical approach that permits identification of all possible calcaneal branches.

  3. Generalized sheath criterion for arbitrary degenerate plasmas

    NASA Astrophysics Data System (ADS)

    Akbari-Moghanjoughi, M.

    2017-01-01

    In this research, we study the generalized sheath criterion for plasmas with an arbitrary degree of electron degeneracy and temperature, ranging from the classical dilute regime to the fully degenerate quantum plasmas. The latter may be relevant to warm dense matter and/or laboratory high energy density matter or even astrophysical stellar plasmas. The hydrostatic one dimensional model is used to establish the generalized Bohm's criterion for sheath entrance ion speed limits, and the small amplitude theory of the sheath problem, which accurately describes the sheath parameters for lower ion acoustic Mach numbers, is developed. Our results indicate that the sheath characteristic parameters such as electrostatic potential and density profiles, as well as the wall potential and the sheath length, are significantly affected by plasma parameters such as the ion and electron temperature and number densities in the plasma region. In particular, there are fundamental differences between sheath structures of the dilute classical plasmas and those of dense quantum ones.

  4. Unusual median nerve schwannoma: a case presentation.

    PubMed

    Anghel, Andrea; Tudose, Irina; Terzea, Dana; Răducu, Laura; Sinescu, Ruxandra Diana

    2014-01-01

    Peripheral nerve sheath tumors are common soft tissue neoplasms and their characterization is often challenging. Although the surgical pathology defines some typical entities, some degree of controversy regarding the classification of these tumors still exists. Newer imagistic and histopathological techniques are crucial for their accurate diagnosis and grading. We present an unusual case of median nerve schwannoma in a young patient, discussing the clinical, surgical and pathological elements, including immunohistochemistry.

  5. Graphics processing unit-assisted lossless decompression

    DOEpatents

    Loughry, Thomas A.

    2016-04-12

    Systems and methods for decompressing compressed data that has been compressed by way of a lossless compression algorithm are described herein. In a general embodiment, a graphics processing unit (GPU) is programmed to receive compressed data packets and decompress such packets in parallel. The compressed data packets are compressed representations of an image, and the lossless compression algorithm is a Rice compression algorithm.

  6. SEROTONIN AND OTHER VASOACTIVE AGENTS IN EXPERIMENTAL DECOMPRESSION SICKNESS,

    DTIC Science & Technology

    SEROTONIN, DECOMPRESSION SICKNESS), (*VASOACTIVE AGENTS, DECOMPRESSION SICKNESS), RATS, EXERCISE(PHYSIOLOGY), DOSAGE, CHEMOTHERAPEUTIC AGENTS, BLOOD ANALYSIS, TOXICITY, BLOOD CIRCULATION, MORTALITY RATES , CANADA

  7. Central Retinal Vein Occlusion Resolving After Orbital Decompression in Thyroid Eye Disease.

    PubMed

    Grob, Seanna R; Yoon, Michael K

    A 49-year-old male presented with proptosis and was found to have optic nerve edema with peripapillary hemorrhages. Diagnostic testing showed a suppressed thyroid-stimulating hormone. CT orbits showed homogenous tendon-sparing enlargement of the medial and inferior rectus muscles, characteristic of thyroid eye disease. Intravenous methylprednisolone was administered given the concern for compressive optic neuropathy. He initially had improvement of his symptoms, so orbital decompression was deferred. Subsequently he presented with worsening diplopia and right proptosis, a new afferent pupillary defect, and a cecocentral visual field defect. Dilated examination revealed significant optic nerve head edema and diffuse retinal hemorrhages in all 4 quadrants consistent with a central retinal vein occlusion. The patient underwent an urgent 3-wall orbital decompression on the right. Close follow up postoperatively showed resolution of the central retinal vein occlusion and the associated optic disc edema, peripapillary hemorrhages, and macular edema. Orbital decompression is known to improve many manifestations of thyroid eye disease, but this is the first report of orbital decompression resulting in resolution of a central retinal vein occlusion.

  8. Xenon Blocks Neuronal Injury Associated with Decompression

    PubMed Central

    Blatteau, Jean-Eric; David, Hélène N.; Vallée, Nicolas; Meckler, Cedric; Demaistre, Sebastien; Lambrechts, Kate; Risso, Jean-Jacques; Abraini, Jacques H.

    2015-01-01

    Despite state-of-the-art hyperbaric oxygen (HBO) treatment, about 30% of patients suffering neurologic decompression sickness (DCS) exhibit incomplete recovery. Since the mechanisms of neurologic DCS involve ischemic processes which result in excitotoxicity, it is likely that HBO in combination with an anti-excitotoxic treatment would improve the outcome in patients being treated for DCS. Therefore, in the present study, we investigated the effect of the noble gas xenon in an ex vivo model of neurologic DCS. Xenon has been shown to provide neuroprotection in multiple models of acute ischemic insults. Fast decompression compared to slow decompression induced an increase in lactate dehydrogenase (LDH), a well-known marker of sub-lethal cell injury. Post-decompression administration of xenon blocked the increase in LDH release induced by fast decompression. These data suggest that xenon could be an efficient additional treatment to HBO for the treatment of neurologic DCS. PMID:26469983

  9. Xenon Blocks Neuronal Injury Associated with Decompression.

    PubMed

    Blatteau, Jean-Eric; David, Hélène N; Vallée, Nicolas; Meckler, Cedric; Demaistre, Sebastien; Lambrechts, Kate; Risso, Jean-Jacques; Abraini, Jacques H

    2015-10-15

    Despite state-of-the-art hyperbaric oxygen (HBO) treatment, about 30% of patients suffering neurologic decompression sickness (DCS) exhibit incomplete recovery. Since the mechanisms of neurologic DCS involve ischemic processes which result in excitotoxicity, it is likely that HBO in combination with an anti-excitotoxic treatment would improve the outcome in patients being treated for DCS. Therefore, in the present study, we investigated the effect of the noble gas xenon in an ex vivo model of neurologic DCS. Xenon has been shown to provide neuroprotection in multiple models of acute ischemic insults. Fast decompression compared to slow decompression induced an increase in lactate dehydrogenase (LDH), a well-known marker of sub-lethal cell injury. Post-decompression administration of xenon blocked the increase in LDH release induced by fast decompression. These data suggest that xenon could be an efficient additional treatment to HBO for the treatment of neurologic DCS.

  10. Pressureless Orbital Decompression for Myopic Proptosis.

    PubMed

    Rajak, Saul N; McGovern, Richard A; Selva, Dinesh

    2017-01-01

    Orbital decompression surgery increases the orbital volume. It has rarely been used for proptosis of the large highly myopic globe. However, external decompression surgery carries significant risks because of the large thin-walled globe. The authors report the first use of endoscopic medial wall orbital decompression surgery in this setting to obviate the risk of globe pressure.Endoscopic medial wall decompression brought about a 4 mm reduction of proptosis, correction of exotropia and elimination of retrobulbar ache providing good symmetry with the fellow eye.Endoscopic medial wall orbital decompression can be very effective for correcting the proptosis of high myopia and minimizes the risk of damage to the very large, thin-walled globe.

  11. Chemically extracted acellular allogeneic nerve graft combined with ciliary neurotrophic factor promotes sciatic nerve repair

    PubMed Central

    Zhang, Yanru; Zhang, Hui; Katiella, Kaka; Huang, Wenhua

    2014-01-01

    A chemically extracted acellular allogeneic nerve graft can reduce postoperative immune rejection, similar to an autologous nerve graft, and can guide neural regeneration. However, it remains poorly understood whether a chemically extracted acellular allogeneic nerve graft combined with neurotrophic factors provides a good local environment for neural regeneration. This study investigated the repair of injured rat sciatic nerve using a chemically extracted acellular allogeneic nerve graft combined with ciliary neurotrophic factor. An autologous nerve anastomosis group and a chemical acellular allogeneic nerve bridging group were prepared as controls. At 8 weeks after repair, sciatic functional index, evoked potential amplitude of the soleus muscle, triceps wet weight recovery rate, total number of myelinated nerve fibers and myelin sheath thickness were measured. For these indices, values in the three groups showed the autologous nerve anastomosis group > chemically extracted acellular nerve graft + ciliary neurotrophic factor group > chemical acellular allogeneic nerve bridging group. These results suggest that chemically extracted acellular nerve grafts combined with ciliary neurotrophic factor can repair sciatic nerve defects, and that this repair is inferior to autologous nerve anastomosis, but superior to chemically extracted acellular allogeneic nerve bridging alone. PMID:25221592

  12. Ultrasound-guided rectus sheath block in children with umbilical hernia: Case series.

    PubMed

    Alsaeed, Abdul Hamid; Thallaj, Ahmed; Khalil, Nancy; Almutaq, Nada; Aljazaeri, Ayman

    2013-10-01

    Umbilical hernia repair, a common day-case surgery procedure in children, is associated with a significant postoperative pain. The most popular peripheral nerve blocks used in umbilical hernia repair are rectus sheath infiltration and caudal block. The rectus sheath block may offer improved pain relief following umbilical hernia repair with no undesired effects such as lower limb motor weakness or urinary retention seen with caudal block which might delay discharge from the hospital. Ultrasound guidance of peripheral nerve blocks has reduced the number of complications and improved the quality of blocks. The aim of this case series is to assess the post rectus sheath block pain relief in pediatric patients coming for umbilical surgery. Twenty two (22) children (age range: 1.5-8 years) scheduled for umbilical hernia repair were included in the study. Following the induction of general anesthesia, the ultrasonographic anatomy of the umbilical region was studied with a 5-16 MHz 50 mm linear probe. An ultrasound-guided posterior rectus sheath block of both rectus abdominis muscles (RMs) was performed (total of 44 punctures). An in-plain technique using Stimuplex A insulated facet tip needle 22G 50mm. Surgical conditions, intraoperative hemodynamic parameters, and postoperative analgesia by means of the modified CHEOPS scale were evaluated. ultrasonograghic visualization of the posterior sheath was possible in all patients. The ultrasound guided rectus sheath blockade provided sufficient analgesia in all children with no need for additional analgesia except for one patient who postoperatively required morphine 0.1 mg/kg intravenously. There were no complications. Ultrasound guidance enables performances of an effective rectus sheath block for umbilical hernia. Use of the Stimuplex A insulated facet tip needle 22G 50mm provides easy, less traumatic skin and rectus muscle penetration and satisfactory needle visualiza.

  13. Comparative Oncogenomics for Peripheral Nerve Sheath Cancer Gene Discovery

    DTIC Science & Technology

    2015-06-01

    transcriptional control (Ncoa3, Nr4a3, Zscan22), vesicular trafficking (Napa) and cell motility (Sept6, Vcl). It was also notable that some small CNVs that...metastasis; regulates lysosomal trafficking Nr4a3 (nuclear receptor subfamily 4, group A, member 3) Ligand-dependent transcription factor Aldob...protein attachment protein alpha) Trans-Golgi vesicle trafficking Bbc3 (Bcl binding component 3; PUMA) p53-regulated inducer of apoptosis Mark4

  14. Morphology of human intracardiac nerves: an electron microscope study

    PubMed Central

    PAUZIENE, NERINGA; PAUZA, DAINIUS H.; STROPUS, RIMVYDAS

    2000-01-01

    Since many human heart diseases involve both the intrinsic cardiac neurons and nerves, their detailed normal ultrastructure was examined in material from autopsy cases without cardiac complications obtained no more than 8 h after death. Many intracardiac nerves were covered by epineurium, the thickness of which was related to nerve diameter. The perineurial sheath varied from nerve to nerve and, depending on nerve diameter, contained up to 12 layers of perineurial cells. The sheaths of the intracardiac nerves therefore become progressively attenuated during their course in the heart. The intraneural capillaries of the human heart differ from those in animals in possessing an increased number of endothelial cells. A proportion of the intraneural capillaries were fenestrated. The number of unmyelinated axons within unmyelinated nerve fibres was related to nerve diameter, thin cardiac nerves possessing fewer axons. The most distinctive feature was the presence of stacks of laminated Schwann cell processes unassociated with axons that were more frequent in older subjects. Most unmyelinated and myelinated nerve fibres showed normal ultrastructure, although a number of profiles displayed a variety of different axoplasmic contents. Collectively, the data provide baseline information on the normal structure of intracardiac nerves in healthy humans which may be useful for assessing the degree of nerve damage both in autonomic and sensory neuropathies in the human heart. PMID:11117629

  15. [Classification of altitude decompression sickness].

    PubMed

    Katuntsev, V P

    2000-01-01

    The article is devoted to the discussion of principles of and approaches to classification of altitude decompression sickness (DCS), one of the most methodically formidable aspects of the problem. Based on his own multiyear experience in altitude DCS investigations and critical review of literature, the author reasons his concept of clinical classification of altitude DCS. The author's concept places emphasis on obligatory consideration of three stages in DCS development: A--pre-disease (the premorbid syndrome), B--uncomplicated (light) and C--complicated (severe) forms. The objective sign of the premorbid state is "silent" gas bubbles in organism detectable by ultrasonic devices. Signs of uncomplicated altitude DCS are musculoarticular pains, local edema and skin itching. Complicated altitude DCS is diagnosed by systemic (respiratory, neurological and cardiovascular) disorders.

  16. Decompression sickness in caisson workers

    PubMed Central

    Ghawabi, Samir H. El; Mansour, Mohamed B.; Youssef, Fatma L.; Ghawabi, Mohamed H. El; Latif, Mohamed M. Abd El

    1971-01-01

    El Ghawabi, S. H., Mansour, M. B., Youssef, F. L., El Ghawabi, M. H., and Abd El Latif, M. M. (1971).Brit. J. industr. Med.,28, 323-329. Decompression sickness in caisson workers. An investigation of 55 bridge construction workers is reported. The overall bends rate was 0·97%. (The term `bends' as used in this study is defined in the paper.) Chokes were encountered in 67·27% of workers. A clinical, haematological, and radiological study was performed. Definite bony changes were found in 43·6% of all workers; 91·6% of these had lesions around the elbow. The presence of dense areas in the neck of the scapula is reported in two cases for the first time. The relatively high haematocrit value is thought to play a part in the pathogenesis of bone infarction through its relation with blood viscosity. Images PMID:5124832

  17. libpolycomp: Compression/decompression library

    NASA Astrophysics Data System (ADS)

    Tomasi, Maurizio

    2016-04-01

    Libpolycomp compresses and decompresses one-dimensional streams of numbers by means of several algorithms. It is well-suited for time-ordered data acquired by astronomical instruments or simulations. One of the algorithms, called "polynomial compression", combines two widely-used ideas (namely, polynomial approximation and filtering of Fourier series) to achieve substantial compression ratios for datasets characterized by smoothness and lack of noise. Notable examples are the ephemerides of astronomical objects and the pointing information of astronomical telescopes. Other algorithms implemented in this C library are well known and already widely used, e.g., RLE, quantization, deflate (via libz) and Burrows-Wheeler transform (via libbzip2). Libpolycomp can compress the timelines acquired by the Planck/LFI instrument with an overall compression ratio of ~9, while other widely known programs (gzip, bzip2) reach compression ratios less than 1.5.

  18. Transforaminal Endoscopic Decompression for Displaced End Plate Fracture After Lateral Lumbar Interbody Fusion: Technical Note.

    PubMed

    Wagner, Ralf; Telfeian, Albert E; Krzok, Guntram; Iprenburg, Menno

    2017-10-01

    Lateral lumbar interbody fusion is a minimally invasive approach to anterior spinal column fusion, deformity correction, and indirect decompression of the lumbar spine. A rarely reported possible complication of the procedure is end plate fracture, which has the potential for nerve root compression. Here we present a case of end plate fracture and nerve compression after stand-alone lateral lumbar interbody fusion, its diagnosis, and its subsequent successful treatment with transforaminal endoscopic spine surgery. The case highlights the possible role for minimally invasive endoscopic surgery as a rescue procedure after fusion complication. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Piezosurgery for orbital decompression surgery in thyroid associated orbitopathy.

    PubMed

    Ponto, Katharina A; Zwiener, Isabella; Al-Nawas, Bilal; Kahaly, George J; Otto, Anna F; Karbach, Julia; Pfeiffer, Norbert; Pitz, Susanne

    2014-12-01

    The purpose of this study was to assess a piezosurgical device as a novel tool for bony orbital decompression surgery. At a multidisciplinary orbital center, 62 surgeries were performed in 40 patients with thyroid associated orbitopathy (TAO). Within this retrospective case-series, we analyzed the medical records of these consecutive unselected patients. The reduction of proptosis was the main outcome measure. Indications for a two (n = 27, 44%) or three wall (35, 56%) decompression surgery were proptosis (n = 50 orbits, 81%) and optic neuropathy (n = 12, 19%). Piezosurgery enabled precise bone cuts without intraoperative complications. Proptosis decreased from 23.6 ± 2.8 mm (SD) by 3 mm (95% CI: -3.6 to -2.5 mm) after surgery and stayed stable at 3 months (-3 mm, 95% CI: -3.61 to -2.5 mm, p < 0.001, respectively). The effect was higher in those with preoperatively higher values (>24 mm versus ≤ 24 mm: -3.4 mm versus -2.81 mm before discharge from hospital and -4.1 mm versus -2.1 mm at 3 months: p < 0.001, respectively). After a mean long-term follow-up period of 14.6 ± 10.4 months proptosis decreased by further -0.7 ± 2.0 mm (p < 0.001). Signs of optic nerve compression improved after surgery. Infraorbital hypesthesia was present in 11 of 21 (52%) orbits 3 months after surgery. The piezosurgical device is a useful tool for orbital decompression surgery in TAO. By cutting bone selectively, it is precise and reduces the invasiveness of surgery. Nevertheless, no improvement in outcome or reduction in morbidity over conventional techniques has been shown so far. Copyright © 2014 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  20. Is carpal tunnel decompression warranted for HNPP?

    PubMed

    Earle, Nicholas; Zochodne, Douglas W

    2013-12-01

    The role of carpal tunnel decompression surgery for patients that have hereditary neuropathy with liability to pressure palsy (HNPP) is currently unknown. Since recovery from carpal tunnel compression is often associated with remyelination or nodal reconstruction rather than axonal regeneration, it is uncertain whether the PMP22 deletion associated with HNPP interrupts myelin or nodal reconstitution. We describe two patients with genetically confirmed HNPP and symptomatic carpal tunnel syndrome that had clinical and electrophysiological improvement after surgical decompression. The findings indicate a capacity for conduction repair in HNPP. They also suggest a need for further investigation and discussion around whether to offer carpal tunnel decompression to symptomatic HNPP patients.

  1. Aluminum Wire Rope Polyethylene Sheathing Failure.

    DTIC Science & Technology

    1997-12-01

    of polyethylene taken from sheathed wire rope samples with and without cracking . Sample Melting Point (°C) Heat of Fusion (J/g) Percent...The cracked polyethylene sheathing was made from a higher density PE than the uncracked sheathing. It failed when it was wound onto a cable reel...12, 512 (1979). 6. A. Lustiger, ’ Environmental Stress Cracking : The Phenomenon and its Utility’, Chapter 16 in Failure of Plastics, edited by W

  2. Genomic and Expression Profiling of Benign and Malignant Nerve Sheath Profiling of Benign and Malignant Nerve Sheath

    DTIC Science & Technology

    2007-05-01

    Expression of epidermal growth factor receptor, ERBB2 and KIT in adult soft tissue sarcomas: a clinicopathologic study of 281 cases. Cancer 103: 1881-90...TERMS miRNA microarrays, expression profiling, tissue microarrays Immunohistochemistry 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF...features of the transition of NF to MPNST (see 3rd annual report). We hypothesize that microRNA ( miRNA ) expression differences, as yet unstudied in

  3. Ureteral access strategies: pro-access sheath.

    PubMed

    Vanlangendonck, Richard; Landman, Jaime

    2004-02-01

    Routine use of the ureteral access sheath during flexible ureteroscopic procedures provides consistent, reliable, and unencumbered access to the upper tracts. The ureteral access sheath can be reliably and easily deployed if used properly and requires no special training. As such, it can be easily adopted into current urologic practice. Not only does the access sheath facilitate rapid, repeated, and atraumatic access to the upper tracts, but it also avoids back-loading over a superstiff guidewire, which may incur costly damage to the ureteroscope. The access sheath reduces overall costs and decreases operative times. Furthermore, application of a ureteral access sheath reduces the frustration associated with complex and some routine ureteroscopic procedures by optimizing irrigant flow to improve the surgeon's endoscopic vision while minimizing the intrarenal pressures that the kidney must tolerate. There is no evidence that the access sheath results in clinically significant ureteral ischemia, and extensive clinical use of the access sheath for long procedures has not resulted in increased stricture formation. Finally, the ureteral access sheath is useful for other procedures, such as PCNL, by improving visualization and minimizing the requirement for multiple percutaneous access sites. Winston Churchill said it best: "Give us the tools and we will finish the job." Industry has provided urologists with the tools in the form of advanced flexible ureteroscopes, the holmium laser, nitinol baskets, and the ureteral access sheath. Now it is up to urologists to finish the job.

  4. Transient sheath overvoltages in armored power cables

    SciTech Connect

    Gustavsen, B.; Sletbak, J.

    1996-07-01

    This paper is concerned with methods of limiting the build-up of transient voltages between sheath and armor in long armored power cables. Calculations by a frequency dependent cable model demonstrate that this voltage can be efficiently limited to an acceptable level by introducing sheath-armor bondings at regular intervals, or by using a semiconductive sheath-armor interlayer. The paper investigates the required minimum length between bondings, as well as the required conductivity of the sheath-armor interlayer if the use of bondings is to be avoided.

  5. Gold ink coating of thermocouple sheaths

    DOEpatents

    Ruhl, H. Kenneth

    1992-01-01

    A method is provided for applying a gold ink coating to a thermocouple sheath which includes the steps of electropolishing and oxidizing the surface of the thermocouple sheath, then dipping the sheath into liquid gold ink, and finally heat curing the coating. The gold coating applied in this manner is highly reflective and does not degrade when used for an extended period of time in an environment having a temperature over 1000.degree. F. Depending on the application, a portion of the gold coating covering the tip of the thermocouple sheath is removed by abrasion.

  6. Chapter 2: Development of the peripheral nerve.

    PubMed

    Kaplan, Suleyman; Odaci, Ersan; Unal, Bunyami; Sahin, Bunyamin; Fornaro, Michele

    2009-01-01

    Normal function of the peripheral nerve (PN) is based on morphological integrity and relationship between axons, Schwann cells, and connective sheaths, which depends on the correct development of all these components. Most of the relevant studies in this field were carried out using animal models, since reports on the development of the human PNs from the time of prenatal formation to postnatal development are limited as it is quite difficult to find many nerves in fetuses. In this review paper, we will address the main developmental stages of axons, Schwann cells, and connective tissue sheaths in PNs. Knowledge on the development of PNs and their main components is important for the study of nerve repair and regeneration. This knowledge can be helpful for designing innovative treatment strategies since, like with other organs, the development and regeneration processes share many biological features.

  7. Decompression models: review, relevance and validation capabilities.

    PubMed

    Hugon, J

    2014-01-01

    For more than a century, several types of mathematical models have been proposed to describe tissue desaturation mechanisms in order to limit decompression sickness. These models are statistically assessed by DCS cases, and, over time, have gradually included bubble formation biophysics. This paper proposes to review this evolution and discuss its limitations. This review is organized around the comparison of decompression model biophysical criteria and theoretical foundations. Then, the DCS-predictive capability was analyzed to assess whether it could be improved by combining different approaches. Most of the operational decompression models have a neo-Haldanian form. Nevertheless, bubble modeling has been gaining popularity, and the circulating bubble amount has become a major output. By merging both views, it seems possible to build a relevant global decompression model that intends to simulate bubble production while predicting DCS risks for all types of exposures and decompression profiles. A statistical approach combining both DCS and bubble detection databases has to be developed to calibrate a global decompression model. Doppler ultrasound and DCS data are essential: i. to make correlation and validation phases reliable; ii. to adjust biophysical criteria to fit at best the observed bubble kinetics; and iii. to build a relevant risk function.

  8. Auto-decompression system for engines

    SciTech Connect

    Onda, T.

    1988-12-13

    This patent describes a valve control device for an engine having a combustion chamber, a valve controlling communication with the chamber, a camshaft rotatably mounted in the engine, a valve motion cam fixed to the camshaft for rotation therewith, and a valve actuation mechanism including a cam follower engageable with the valve motion cam, the valve control device comprising: a decompression cam carried by the camshaft axially adjacent the valve motion cam, the decompression cam including a base circle portion defining an outer peripheral surface smaller in radial extent than the outer peripheral surface of the valve motion cam and having an inner bore to loosely encircle the camshaft; means for adjusting the position of the decomposition cam with respect to the camshaft between two locations including a first location on which the outer peripheral surface of the decompression cam extends radially outwardly from the axis of the camshaft to an extent greater than that of the valve motion cam to engage the cam follower for decompression operation of the valve, and a second location at which the outer peripheral surface of the decompression cam extends radially outwardly from the axis of the camshaft to an extent less than that of the valve motion cam whereby the valve motion cam engages the cam follower for normal operation of the valve; and means responsive to the rotational speed of the camshaft for automatically moving the decompression cam between the first and second locations.

  9. The Effects of Normal Aging on Myelinated Nerve Fibers in Monkey Central Nervous System

    PubMed Central

    Peters, Alan

    2009-01-01

    The effects of aging on myelinated nerve fibers of the central nervous system are complex. Many myelinated nerve fibers in white matter degenerate and are lost, leading to some disconnections between various parts of the central nervous system. Other myelinated nerve fibers are affected differently, because only their sheaths degenerate, leaving the axons intact. Such axons are remyelinated by a series of internodes that are much shorter than the original ones and are composed of thinner sheaths. Thus the myelin-forming cells of the central nervous system, the oligodendrocytes, remain active during aging. Indeed, not only do these neuroglial cell remyelinate axons, with age they also continue to add lamellae to the myelin sheaths of intact nerve fibers, so that sheaths become thicker. It is presumed that the degeneration of myelin sheaths is due to the degeneration of the parent oligodendrocyte, and that the production of increased numbers of internodes as a consequence of remyelination requires additional oligodendrocytes. Whether there is a turnover of oligodendrocytes during life has not been studied in primates, but it has been established that over the life span of the monkey, there is a substantial increase in the numbers of oligodendrocytes. While the loss of some myelinated nerve fibers leads to some disconnections, the degeneration of other myelin sheaths and the subsequent remyelination of axons by shorter internodes slow down the rate conduction along nerve fibers. These changes affect the integrity and timing in neuronal circuits, and there is evidence that they contribute to cognitive decline. PMID:19636385

  10. [Different posterior decompression for patients with spinal canal stenosis in the upper thoracic and cervical spine].

    PubMed

    Yao, Y Z; Yin, R F; Huang, J; Liu, D L; Zang, H

    2016-07-05

    To retrospectively investigate the clinical manifestation of patients with spinal stenosis in the upper thoracic and cervical spine by posterior decompression in different ways. From January 2010 to December 2015, 18 patients of that complicated phenomenon were studied in Department of Orthopaedic Surgery, China-Japan Union Hospital, Jilin University.Ten patients received one-stage combined decompression (group A); while the other 8 received multi-stage posterior decompression(group B). The Visual analogue scale (JOA), thoracic Cobb and range of motion(ROM) were compared. No statistically significant inter-group difference existed in preoperative JOA score[(9.1±2.6)vs (9.1±2.2)]and postoperative JOA score[(15.4±1.2)vs(13.8±4.5)], but the mean recovery rate of nerve function of group A(79%±15%)is better than that of group B(69%±34%). All the approaches are effective for the treatment of patients with spinal stenosis in the upper thoracic and cervical spine, while one-staged combined decompression was better than double-staged operation.

  11. Acclimation to decompression sickness in rats.

    PubMed

    Montcalm-Smith, E A; McCarron, R M; Porter, W R; Lillo, R S; Thomas, J T; Auker, C R

    2010-03-01

    Protection against decompression sickness (DCS) by acclimation to hyperbaric decompression has been hypothesized but never proven. We exposed rats to acclimation dives followed by a stressful "test" dive to determine whether acclimation occurred. Experiments were divided into two phases. Phase 1 rats were exposed to daily acclimation dives of hyperbaric air for 30 min followed by rapid decompression on one of the following regimens: 70 ft of seawater (fsw) for 9 days (L70), 70 fsw for 4 days (S70), 40 fsw for 9 days (L40), 40 fsw for 4 days (S40), or unpressurized sham exposure for 9 days (Control). On the day following the last exposure, all were subjected to a "test" dive (175 fsw, 60 min, rapid decompression). Both L70 and S70 rats had significantly lower incidences of DCS than Control rats (36% and 41% vs. 62%, respectively). DCS incidences for the other regimens were lower than in Control rats but without statistical significance. Phase 2 used the most protective regimen from phase 1 (L70); rats were exposed to L70 or a similar regimen with a less stressful staged decompression. Another group was exposed to a single acclimation dive (70 fsw/30 min) on the day before the test dive. We observed a nonsignificant trend for the rapidly decompressed L70 dives to be more protective than staged decompression dives (44% vs. 51% DCS incidence). The single acclimation dive regimen did not provide protection. We conclude that protection against DCS can be attained with acclimating exposures that do not themselves cause DCS. The deeper acclimation dive regimens (70 fsw) provided the most protection.

  12. A simple model of radial nerve injury in the rhesus monkey to evaluate peripheral nerve repair

    PubMed Central

    Wang, Dong; Huang, Xijun; Fu, Guo; Gu, Liqiang; Liu, Xiaolin; Wang, Honggang; Hu, Jun; Yi, Jianhua; Niu, Xiaofeng; Zhu, Qingtang

    2014-01-01

    Current research on bone marrow stem cell transplantation and autologous or xenogenic nerve transplantation for peripheral nerve regeneration has mainly focused on the repair of peripheral nerve defects in rodents. In this study, we established a standardized experimental model of radial nerve defects in primates and evaluated the effect of repair on peripheral nerve injury. We repaired 2.5-cm lesions in the radial nerve of rhesus monkeys by transplantation of autografts, acellular allografts, or acellular allografts seeded with autologous bone marrow stem cells. Five months after surgery, regenerated nerve tissue was assessed for function, electrophysiology, and histomorphometry. Postoperative functional recovery was evaluated by the wrist-extension test. Compared with the simple autografts, the acellular allografts and allografts seeded with bone marrow stem cells facilitated remarkable recovery of the wrist-extension functions in the rhesus monkeys. This functional improvement was coupled with radial nerve distal axon growth, a higher percentage of neuron survival, increased nerve fiber density and diameter, increased myelin sheath thickness, and increased nerve conduction velocities and peak amplitudes of compound motor action potentials. Furthermore, the quality of nerve regeneration in the bone marrow stem cells-laden allografts group was comparable to that achieved with autografts. The wrist-extension test is a simple behavioral method for objective quantification of peripheral nerve regeneration. PMID:25206757

  13. Treating facial nerve palsy by true termino-lateral hypoglossal-facial nerve anastomosis.

    PubMed

    Sleilati, F H; Nasr, M W; Stephan, H A; Asmar, Z D; Hokayem, N E

    2010-11-01

    Hypoglossal-facial nerve anastomosis is a time-proven technique for the repair of facial nerve palsy. Efforts have been made to reduce hypoglossal nerve injury, the main drawback of the technique. In this study, the anastomosis is a true termino-lateral neurorrhaphy with only an epineural window in the hypoglossal nerve sheath. A re-routing technique of the temporal facial nerve is also performed to allow a direct anastomosis to the hypoglossal nerve without the need for a jump graft. The first three results reported are very encouraging, with a satisfactory return of facial mimics and without any impairment of lingual function. Copyright © 2009 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  14. Hypobaric Decompression Sickness Treatment Model.

    PubMed

    Conkin, Johnny; Abercromby, Andrew F J; Dervay, Joseph P; Feiveson, Alan H; Gernhardt, Michael L; Norcross, Jason R; Ploutz-Snyder, Robert; Wessel, James H

    2015-06-01

    The Hypobaric Decompression Sickness (DCS) Treatment Model links a decrease in computed bubble volume from increased pressure (ΔP), increased oxygen (O2) partial pressure, and passage of time during treatment to the probability of symptom resolution [P(SR)]. The decrease in offending volume is realized in two stages: 1) during compression via Boyles law; and 2) during subsequent dissolution of the gas phase via the oxygen window. We established an empirical model for the P(SR) while accounting for multiple symptoms within subjects. The data consisted of 154 cases of hypobaric DCS symptoms with ancillary information from tests on 56 men and 18 women. Our best estimated model is P(SR)=1/(1+exp(-(ln(ΔP)-1.510+0.795×AMB-0.00308×Ts)/0.478)), where ΔP is pressure difference (psid); AMB=1 if ambulation took place during part of the altitude exposure, otherwise AMB=0; and Ts is the elapsed time in minutes from the start of altitude exposure to recognition of a DCS symptom. Values of ΔP as inputs to the model would be calculated from the Tissue Bubble Dynamics Model based on the effective treatment pressure: ΔP=P2-P1|=P1×V1/V2-P1, where V1 is the computed volume of a bubble at low pressure P1 and V2 is computed volume after a change to a higher pressure P2. If 100% ground-level oxygen was breathed in place of air, then V2 continues to decrease through time at P2 at a faster rate.

  15. Trigemino-cardiac reflex during microvascular trigeminal decompression in cases of trigeminal neuralgia.

    PubMed

    Schaller, Bernhard

    2005-01-01

    The trigemino-cardiac reflex (TCR) is a well-recognized phenomenon consisting of bradycardia, arterial hypotension, apnea, and gastric hypermotility during ocular surgery or other manipulations in and around the orbit. Thus far, it could bee shown that central stimulation of the trigeminal nerve during transsphenoidal surgery and surgery for tumors in the cerebellopontine angle can lead to TCR. In cases of microvascular trigeminal decompression for trigeminal neuralgia, no data of the possible occurrence of TCR are available. TCR was defined as a drop in mean arterial blood pressure (MABP) and the heart rate (HR) of more than 20% to the baseline values before the stimulus and coinciding with the manipulation of the trigeminal nerve. Electronic anesthetic recorded perioperative HR and MABP values were reviewed retrospectively in 28 patients who received microvascular trigeminal decompression in cases of trigeminal neuralgia and were divided into two subgroups on the basis of occurrence of TCR during surgery. Of the 28 patients, 5 (18%) showed evidence of TCR during manipulation at the trigeminal radix by separation from microvascular structures. Their HR fell 46% and their MABP 57% during operative procedures near the trigeminal nerve as compared with levels immediately before the stimulus. After cessation of manipulation, HR and MABP returned (spontaneously) to levels before the stimulus. Risk factors of TCR were compared with results from the literature. In conclusion, the present results give evidence of TCR during manipulation of the central part of the trigeminal nerve during microvascular trigeminal decompression in cases of trigeminal neuralgia under a standardized anesthetic protocol.

  16. Microvascular decompression for elderly patients with trigeminal neuralgia.

    PubMed

    Phan, Kevin; Rao, Prashanth J; Dexter, Mark

    2016-07-01

    Microvascular decompression (MVD) has been demonstrated to be an excellent surgical treatment approach in younger patients with trigeminal neuralgia (TN). However, it is not clear whether there are additional morbidity and mortality risks for MVD in the elderly population. We performed a systematic literature review using six electronic databases for studies that compared outcomes for MVD for TN in elderly (cut-off ⩾60, 65, 70years) versus younger populations. Outcomes examined included success rate, deaths, strokes, thromboembolism, meningitis, cranial nerve deficits and cerebrospinal fluid leaks. There were 1524 patients in the elderly cohort and 3488 patients in the younger cohort. There was no significant difference in success rates in elderly versus younger patients (87.5% versus 84.8%; P=0.47). However, recurrence rates were lower in the elderly (11.9% versus 15.6%; P=0.03). The number of deaths in the elderly cohort was higher (0.9% versus 0.1%; P=0.003). Rates of stroke (2.5% versus 1%) and thromboembolism (1.1% versus 0%) were also higher for elderly TN patients. No differences were found for rates of meningitis, cranial nerve deficits or cerebrospinal fluid leak. MVD remains an effective and reasonable strategy in the elderly population. There is evidence to suggest that rates of complications such as death, stroke, and thromboembolism may be significantly higher in the elderly population. The presented results may be useful in the decision-making process for MVD in elderly patients with TN.

  17. Effects of melatonin on peripheral nerve regeneration.

    PubMed

    Turgut, Mehmet; Kaplan, Süleyman

    2011-05-01

    In the available literature, there are thousands of studies on peripheral nerve regeneration using many nerves of several animals at different ages with various types of lesions and different methods of evaluation at certain time of follow-up. Despite many experimental data and clinical observations, there is still no ideal treatment method enhancing peripheral nerve regeneration. In clinical practice, various types of surgical nerve repair techniques do not frequently result in complete recovery due to neuroma formation, lipid peroxidative damage, ischemia and other factors. Recently, a number of neuroscientists demonstrated that pineal neurohormone melatonin (MLT) has an effect on the morphologic features of the nerve tissue, suggesting its neuroprotective, free radical scavenging, antioxidative, and analgesic effects in degenerative diseases of peripheral nerves. At present, it is widely accepted that MLT has a useful effect on axon length and sprouting after traumatic events to peripheral nerves. Our studies using various experimental injury models clearly suggest positive effects of MLT on the number of axons, thickness of myelin sheath by inhibition of collagen accumulation and neuroma formation following traumatic events to peripheral nerves, myelination of developing peripheral nerve after intrauterine ethanol exposure. Nevertheless, further experimental and randomized controlled clinical studies are vital to identify the clinical use of MLT hormone. This is an overview of recent patents and current literature in terms of the effects of MLT on peripheral nerve regeneration based on a critical analysis of electrophysiological, biochemical and light and electron microscopic findings, in addition to functional observations.

  18. Peroneal palsy after bariatric surgery; is nerve decompresion always necessary?

    PubMed

    Ramos-Leví, Ana M; Matías-Guiu, Jordi A; Guerrero, Antonio; Sánchez-Pernaute, Andrés; Rubio, Miguel A

    2013-01-01

    We present two patients who underwent successful bariatric surgery and developed peroneal nerve palsy six months after the procedure. This is an unusual complication which determines a significant functional limitation, mainly because of foot drop, and its presence may be a hallmark of excessive and rapid weight loss. We discuss possible pathogenic mechanisms and therapeutic options, and we emphasize the important role of an adequate nutritional management, in order to avoid the need for a surgical nerve decompression.

  19. Theory of the electron sheath and presheath

    SciTech Connect

    Scheiner, Brett; Baalrud, Scott D.; Yee, Benjamin T.; Hopkins, Matthew M.; Barnat, Edward V.

    2015-12-30

    Here, electron sheaths are commonly found near Langmuir probes collecting the electron saturation current. The common assumption is that the probe collects the random flux of electrons incident on the sheath, which tacitly implies that there is no electron presheath and that the flux collected is due to a velocity space truncation of the electron velocity distribution function (EVDF). This work provides a dedicated theory of electron sheaths, which suggests that they are not so simple. Motivated by EVDFs observed in particle-in-cell(PIC) simulations, a 1D model for the electron sheath and presheath is developed. In the model, under low temperature plasma conditions (Te >> Ti), an electron pressure gradient accelerates electrons in the presheath to a flow velocity that exceeds the electron thermal speed at the sheath edge. This pressure gradient generates large flow velocities compared to what would be generated by ballistic motion in response to the electric field. It is found that in many situations, under common plasma conditions, the electron presheath extends much further into the plasma than an analogous ion presheath. PIC simulations reveal that the ion density in the electron presheath is determined by a flow around the electron sheath and that this flow is due to 2D aspects of the sheath geometry. Simulations also indicate the presence of ion acoustic instabilities excited by the differential flow between electrons and ions in the presheath, which result in sheath edge fluctuations. The 1D model and time averaged PIC simulations are compared and it is shown that the model provides a good description of the electron sheath and presheath.

  20. Theory of the electron sheath and presheath

    DOE PAGES

    Scheiner, Brett; Baalrud, Scott D.; Yee, Benjamin T.; ...

    2015-12-30

    Here, electron sheaths are commonly found near Langmuir probes collecting the electron saturation current. The common assumption is that the probe collects the random flux of electrons incident on the sheath, which tacitly implies that there is no electron presheath and that the flux collected is due to a velocity space truncation of the electron velocity distribution function (EVDF). This work provides a dedicated theory of electron sheaths, which suggests that they are not so simple. Motivated by EVDFs observed in particle-in-cell(PIC) simulations, a 1D model for the electron sheath and presheath is developed. In the model, under low temperaturemore » plasma conditions (Te >> Ti), an electron pressure gradient accelerates electrons in the presheath to a flow velocity that exceeds the electron thermal speed at the sheath edge. This pressure gradient generates large flow velocities compared to what would be generated by ballistic motion in response to the electric field. It is found that in many situations, under common plasma conditions, the electron presheath extends much further into the plasma than an analogous ion presheath. PIC simulations reveal that the ion density in the electron presheath is determined by a flow around the electron sheath and that this flow is due to 2D aspects of the sheath geometry. Simulations also indicate the presence of ion acoustic instabilities excited by the differential flow between electrons and ions in the presheath, which result in sheath edge fluctuations. The 1D model and time averaged PIC simulations are compared and it is shown that the model provides a good description of the electron sheath and presheath.« less

  1. Rectus sheath abscess after laparoscopic appendicectomy

    PubMed Central

    Golash, Vishwanath

    2007-01-01

    Port site wound infection, abdominal wall hematoma and intraabdominal abscess formation has been reported after laparoscopic appendicectomy. We describe here a rectus sheath abscess which occurred three weeks after the laparoscopic appendicectomy. It was most likely the result of secondary infection of the rectus sheath hematoma due to bleeding into the rectus sheath from damage to the inferior epigastric arteries or a direct tear of the rectus muscle. As far as we are aware this complication has not been reported after laparoscopic appendicectomy. PMID:21124654

  2. Side-welded fast response sheathed thermocouple

    DOEpatents

    Carr, Kenneth R.

    1981-01-01

    A method of fabricating the measuring junction of a grounded-junction sheathed thermocouple to obtain fast time response and good thermal cycling performance is provided. Slots are tooled or machined into the sheath wall at the measuring junction, the thermocouple wires are laser-welded into the slots. A thin metal closure cap is then laser-welded over the end of the sheath. Compared to a conventional grounded-junction thermocouple, the response time is 4-5 times faster and the thermal shock and cycling capabilities are substantially improved.

  3. Side-welded fast response sheathed thermocouple

    DOEpatents

    Carr, K.R.

    A method of fabricating the measuring junction of a grounded-junction sheathed thermocouple to obtain fast time response and good thermal cycling performance is provided. Slots are tooled or machined into the sheath wall at the measuring junction, the thermocouple wires are laser-welded into the slots. A thin metal closure cap is then laser-welded over the end of the sheath. Compared to a conventional grounded-junction thermocouple, the response time is 4 to 5 times faster and the thermal shock and cycling capabilities are substantially improved.

  4. Effects of electron emission on sheath potential

    NASA Astrophysics Data System (ADS)

    Dow, Ansel; Khrabrov, Alexander; Kaganovich, Igor; Schamis, Hanna

    2015-11-01

    We investigate the potential profile of a sheath under the influence of surface electron emission. The plasma and sheath profiles are simulated using the Large Scale Plasma (LSP) particle-in-cell code. Using one dimensional models we corroborate the analytical relationship between sheath potential and plasma electron and emitted electron temperatures derived earlier. This work was made possible by funding from the Department of Energy for the Summer Undergraduate Laboratory Internship (SULI) program. This work is supported by the US DOE Contract No. DE-AC02-09CH11466.

  5. Simple Transposition Technique for Microvascular Decompression Using an Expanded Polytetrafluoroethylene “Belt”: Technical Note

    PubMed Central

    TANAKA, Yuichiro; UCHIDA, Masashi; ONODERA, Hidetaka; HIRAMOTO, Jun; YOSHIDA, Yasuyuki

    2014-01-01

    Microvascular decompression (MVD) is a standard surgical procedure for treating vascular compression syndromes. There are two basic ways to perform MVD: interposition using a prosthesis and transposition. With the transposition technique, adhesions and granuloma around the decompression site are avoided, but the required operation is more complex than that for the interposition method. We describe a simple, quick MVD transposition procedure that uses a small “belt” cut from a sheet of 0.3-mm-thick expanded polytetrafluoroethylene membrane. The belt has a hole at the wide end and the other end tapered to a point. The belt is encircled around offending vessels by inserting the pointed end into the hole. The pointed end is then passed through a dural tunnel over the posterior wall of the petrous bone and is tied two or three times. This method avoids the risks involved in handling a surgical needle close to the cranial nerves and vessels. PMID:24097088

  6. Simple transposition technique for microvascular decompression using an expanded polytetrafluoroethylene "belt": technical note.

    PubMed

    Tanaka, Yuichiro; Uchida, Masashi; Onodera, Hidetaka; Hiramoto, Jun; Yoshida, Yasuyuki

    2014-06-17

    Microvascular decompression (MVD) is a standard surgical procedure for treating vascular compression syndromes. There are two basic ways to perform MVD: interposition using a prosthesis and transposition. With the transposition technique, adhesions and granuloma around the decompression site are avoided, but the required operation is more complex than that for the interposition method. We describe a simple, quick MVD transposition procedure that uses a small "belt" cut from a sheet of 0.3-mm-thick expanded polytetrafluoroethylene membrane. The belt has a hole at the wide end and the other end tapered to a point. The belt is encircled around offending vessels by inserting the pointed end into the hole. The pointed end is then passed through a dural tunnel over the posterior wall of the petrous bone and is tied two or three times. This method avoids the risks involved in handling a surgical needle close to the cranial nerves and vessels.

  7. The U.S. Navy decompression computer.

    PubMed

    Butler, F K; Southerland, D

    2001-01-01

    The U.S. Navy has recently approved the Cochran NAVY decompression computer (DC) for use in Naval Special Warfare diving. This action represents the first approval of a diver-worn DC for use in the U.S. Navy. This paper reviews the development and testing of both the decompression algorithm and the hardware chosen for the Navy's DC. The decompression software in the Cochran NAVY is the VVAL 18 algorithm developed at the Navy Experimental Diving Unit (NEDU) by Captain Ed Thalmann. A discussion of the relative conservatism of the VVAL18 algorithm in comparison to the U.S. Navy Standard Air Tables and the basis for the differences between the two is provided. The initial guidelines establishing DC diving practice for the Navy SEAL community are outlined as are plans for future research efforts in U.S. Navy DC diving.

  8. Age, weight and decompression sickness in rats.

    PubMed

    Buzzacott, Peter; Theron, Michael; Mazur, Aleksandra; Wang, Qiong; Lambrechts, Kate; Eftedal, Ingrid; Ardestani, Simin Berenji; Guerrero, François

    2016-01-01

    The aim of this study was to determine if, after controlling for weight, age is associated with decompression sickness (DCS) in rats. Following compression-decompression, male rats aged 11 weeks were observed for DCS. After two weeks recovery, surviving rats were re-dived using the same compression-decompression profile. In this experiment, there was a clear difference between DCS outcome at ages 11 or 13 weeks in matched rats (p = 0.002). Even with weight included in the model, age was significantly associated with DCS (p = 0.01), yet after removal of weight the association was much stronger (p = 0.002). We believe that age is likely to be found associated with the probability of DCS in a larger dataset with a wider range of parameters, after accounting for the effect of weight.

  9. Superficial peroneal nerve anatomic variability changes surgical technique.

    PubMed

    Rosson, Gedge D; Dellon, A Lee

    2005-09-01

    Entrapment of the superficial peroneal nerve is an uncommon entrapment that occurs in sports trauma or fracture and dislocation as the nerve comes under pressure between the underlying muscles and the overlying fascia. Although the superficial peroneal nerve traditionally is depicted as being in the lateral compartment, we have found it in the anterior compartment in some patients. We hypothesized that patients with entrapment of the superficial peroneal nerve were more likely to have this anatomic variant than the normal population and that surgical decompression of both compartments would improve clinical outcome versus the historic surgical approach of decompressing just the lateral compartment. We retrospectively reviewed the location of the superficial peroneal nerve in a consecutive series of 35 limbs in 31 patients with entrapment of the superficial peroneal nerve. The results showed that the location of the superficial peroneal nerve was not different from the reported normal variation. However, the location of the superficial peroneal nerve in the anterior compartment in 47% of the patients in this series suggests that surgeons must explore the anterior and the lateral compartments in each patient with entrapment or neuroma of the superficial peroneal nerve. Therapeutic study, Level IV (case series-no, or historical, control group). See the Guidelines for Authors for a complete description of levels of evidence.

  10. Rehabilitation of the trigeminal nerve

    PubMed Central

    Iro, Heinrich; Bumm, Klaus; Waldfahrer, Frank

    2005-01-01

    When it comes to restoring impaired neural function by means of surgical reconstruction, sensory nerves have always been in the role of the neglected child when compared with motor nerves. Especially in the head and neck area, with its either sensory, motor or mixed cranial nerves, an impaired sensory function can cause severe medical conditions. When performing surgery in the head and neck area, sustaining neural function must not only be highest priority for motor but also for sensory nerves. In cases with obvious neural damage to sensory nerves, an immediate neural repair, if necessary with neural interposition grafts, is desirable. Also in cases with traumatic trigeminal damage, an immediate neural repair ought to be considered, especially since reconstructive measures at a later time mostly require for interposition grafts. In terms of the trigeminal neuralgia, commonly thought to arise from neurovascular brainstem compression, a pharmaceutical treatment is considered as the state of the art in terms of conservative therapy. A neurovascular decompression of the trigeminal root can be an alternative in some cases when surgical treatment is sought after. Besides the above mentioned therapeutic options, alternative treatments are available. PMID:22073060

  11. Decompressive laparotomy for abdominal compartment syndrome

    PubMed Central

    Kimball, E.; Malbrain, M.; Nesbitt, I.; Cohen, J.; Kaloiani, V.; Ivatury, R.; Mone, M.; Debergh, D.; Björck, M.

    2016-01-01

    Background The effect of decompressive laparotomy on outcomes in patients with abdominal compartment syndrome has been poorly investigated. The aim of this prospective cohort study was to describe the effect of decompressive laparotomy for abdominal compartment syndrome on organ function and outcomes. Methods This was a prospective cohort study in adult patients who underwent decompressive laparotomy for abdominal compartment syndrome. The primary endpoints were 28‐day and 1‐year all‐cause mortality. Changes in intra‐abdominal pressure (IAP) and organ function, and laparotomy‐related morbidity were secondary endpoints. Results Thirty‐three patients were included in the study (20 men). Twenty‐seven patients were surgical admissions treated for abdominal conditions. The median (i.q.r.) Acute Physiology And Chronic Health Evaluation (APACHE) II score was 26 (20–32). Median IAP was 23 (21–27) mmHg before decompressive laparotomy, decreasing to 12 (9–15), 13 (8–17), 12 (9–15) and 12 (9–14) mmHg after 2, 6, 24 and 72 h. Decompressive laparotomy significantly improved oxygenation and urinary output. Survivors showed improvement in organ function scores, but non‐survivors did not. Fourteen complications related to the procedure developed in eight of the 33 patients. The abdomen could be closed primarily in 18 patients. The overall 28‐day mortality rate was 36 per cent (12 of 33), which increased to 55 per cent (18 patients) at 1 year. Non‐survivors were no different from survivors, except that they tended to be older and on mechanical ventilation. Conclusion Decompressive laparotomy reduced IAP and had an immediate effect on organ function. It should be considered in patients with abdominal compartment syndrome. PMID:26891380

  12. Evidence Report: Risk of Decompression Sickness (DCS)

    NASA Technical Reports Server (NTRS)

    Conkin, Johnny; Norcross, Jason R.; Wessel, James H. III; Abercromby, Andrew F. J.; Klein, Jill S.; Dervay, Joseph P.; Gernhardt, Michael L.

    2013-01-01

    The Risk of Decompression Sickness (DCS) is identified by the NASA Human Research Program (HRP) as a recognized risk to human health and performance in space, as defined in the HRP Program Requirements Document (PRD). This Evidence Report provides a summary of the evidence that has been used to identify and characterize this risk. Given that tissue inert gas partial pressure is often greater than ambient pressure during phases of a mission, primarily during extravehicular activity (EVA), there is a possibility that decompression sickness may occur.

  13. Orbital decompression for severe dysthyroid eye disease.

    PubMed Central

    Fells, P

    1987-01-01

    Current methods of medical treatment of this difficult condition are briefly reviewed, with comments on the generally unsatisfactory response. Attention is therefore directed to surgical methods and a short history given of the various routes used for orbital decompression. The author's own results of transantral, and more recently ethmoidal, decompression are given, with a detailed description of the technique for the latter approach. An interesting frequent consequence of postoperative A pattern to the ocular movements is discussed in the light of Koornneef's concept of orbital fascial anatomy, and suggestions are made for its avoidance. Images PMID:3828262

  14. Prophylactic nasogastric decompression after emergency laparotomy.

    PubMed

    Sapkota, Ranjan; Bhandari, Ramesh Singh

    2013-01-01

    Post-operative nasogastric intubation after emergency laparotomy is a common practice in many centers, with the intent of hastening the return of bowel function, relieving gastrointestinal discomfort, reducing various post-operative complications and reducing hospital stay. However, bowel rest and gastric decompression have been re-examined in the light of more recent data. Many studies and meta-analyses over the last 50 years have challenged the routine use of nasogastric tubes after laparotomy. The objective of this study is to evaluate the need for routine nasogastric decompression after emergency laparotomy. A prospective, randomized controlled trial was conducted for 12 months (May 1, 2007 to Apr 30, 2008) in the Department of Surgery, Tribhuvan University Teaching Hospital, after ethical approval. Patients were enrolled as per criteria (Box 1), and subsequently allocated by simple randomization into two groups: Group 1 and Group 2. Patients undergoing emergency laparotomy for perforation peritonitis, intestinal obstruction and abdominal trauma were randomized to two groups - with or without nasogastric tube after surgery. Gastric upset, return of bowel function and postoperative complications were compared. Total of 115 patients met the inclusion criteria. There was no statistically significant difference in the occurrence of gastric upset (P: 0.38), wound complications (P: 0.30), respiratory complications (P: 0.30) and anastomotic leak (P: 0.64) between two groups. Bowel function returned in comparable times in both groups (correlation coefficient: 0.14; P: 0.54). Nasogastric tube had to be reinserted in three patients in the group with nasogastric decompression postoperatively, and four in the group without (P: 0.43). Thus, routine nasogastric decompression neither prevented the development of gastrointestinal discomfort nor precluded the need for tube replacement once it was discontinued. For every patient who required post-operative nasogastric

  15. Hypobaric decompression prebreathe requirements and breathing environment

    NASA Technical Reports Server (NTRS)

    Webb, James T.; Pilmanis, Andrew A.

    1993-01-01

    To reduce incidence of decompression sickness (DCS), prebreathing 100 percent oxygen to denitrogenate is required prior to hypobaric decompressions from a sea level pressure breathing environment to pressures lower than 350 mm Hg (20,000 ft; 6.8 psia). The tissue ratio (TR) of such exposures equals or exceeds 1.7; TR being the tissue nitrogen pressure prior to decompression divided by the total pressure after decompression (((0.781)(14.697))/6.758). Designing pressure suits capable of greater pressure differentials, lower TR's, and procedures which limit the potential for DCS occurrence would enhance operational efficiency. The current 10.2 psia stage decompression prior to extravehicular activity (EVA) from the Shuttle in the 100 percent oxygen, 4.3 psia suit, results in a TR of 1.65 and has proven to be relatively free of DCS. Our recent study of zero-prebreathe decompressions to 6.8 psia breathing 100 percent oxygen (TR = 1.66) also resulted in no DCS (N = 10). The level of severe, Spencer Grades 3 or 4, venous gas emboli (VGE) increased from 0 percent at 9.5 psia to 40 percent at 6.8 psia yielding a Probit curve of VGE risk for the 51 male subjects who participated in these recent studies. Earlier, analogous decompressions using a 50 percent oxygen, 50 percent nitrogen breathing mixture resulted in one case of DCS and significantly higher levels of severe VGE, e.g., at 7.8 psia, the mixed gas breathing environment resulted in a 56 percent incidence of severe VGE versus 10 percent with use of 100 percent oxygen. The report of this study recommended use of 100 percent oxygen during zero-prebreathe exposure to 6.8 psia if such a suit could be developed. For future, long-term missions, we suggest study of the effects of decompression over several days to a breathing environment of 150 mmHg O2 and approximately 52 mmHg He as a means of eliminating DCS and VGE hazards during subsequent excursions. Once physiologically adapted to a 4 psia vehicle, base, or space

  16. Decompression-Induced Crystallization of Hydrous Basalt

    NASA Astrophysics Data System (ADS)

    Teasdale, R.; Brooker, R. A.

    2014-12-01

    Decompression-induced crystallization of hydrous basalt during magma ascent from 1.5 kb (150 MPa) is quantified using isothermal decompression TZM experiments. The starting composition is a synthetic glass based on the 1921 Kilauea basalt, with 1% H2O added. In all cases, the liquidus phase is aluminous spinel, followed by clinopyroxene, then plagioclase. The plagioclase liquidus temperatures for isobaric (equilibrium) experiments range from 1175°C (at 1.5 kb) to 1217°C (at 200b), which are 35-75°C hotter than predicted by MELTS (Ghiorso & Sack 1995). Experiments were decompressed at 1kb/hr and quenched at 800, 400, 200, or 100b for three temperatures (1160°, 1150°, and 1140°C). Plagioclase crystals formed during decompression have long axes that range from less than 1 micron to 20 microns. Increasing decompression yields larger plagioclase crystal sizes and aspect ratios for experiments at equal temperatures. However, the number of crystals does not vary systematically, indicating that crystallization is dominated by growth rather than nucleation during decompression. Plagioclase compositions for experiments were measured with University of Bristol's Electron Microprobe and the Hyperprobe with Field Emission Gun. Plagioclase compositions from equilibrium experiments (An60-An80) span the range of those from decompression experiments (An60-An73). Equilibrium experiments generated higher An compositions at lower pressures (500b) than at higher pressure (1.5kb) but do not systematically vary with temperature. Variations in plagioclase compositions are minimal above H2O saturation (100-200°C, based on Papale et al., 2006). Below H2O saturation, An content decreases slightly, by approximately 4% An. One application of this work is better characterization of groundmass crystallization in hydrous basalt as it traverses the conduit during eruption. This work also provides a means of distinguishing groundmass plagioclase related to decompression from crystals

  17. 1991 Volvo Award in experimental studies. Cauda equina syndrome: neurologic recovery following immediate, early, or late decompression.

    PubMed

    Delamarter, R B; Sherman, J E; Carr, J B

    1991-09-01

    An animal model of cauda equina syndrome was developed. Neurologic recovery was analyzed following immediate, early, and delayed decompression. Five experimental groups, each containing six dogs, were studied. Compression of the cauda equina was performed in all 30 dogs following an L6-7 laminectomy. The cauda equina was constricted by 75% in each group. The first group was constricted and immediately decompressed. The remaining groups were constricted for 1 hour, 6 hours, 24 hours, and 1 week, respectively, before being decompressed. Somatosensory evoked potentials were performed before and after surgery, before and immediately after decompression, and 6 weeks following decompression. Daily neurologic exams using the Tarlov grading scale were performed. At 6 weeks postdecompression, all dogs were killed, and the neural elements analyzed histologically. Following compression, all 30 dogs had significant lower extremity weakness, tail paralysis, and urinary incontinence. All dogs recovered significant motor function 6 weeks following decompression. The dogs with immediate decompression generally recovered neurologic function within 2-5 days. The dogs receiving 1-hour and 6-hour compression recovered within 5-7 days. The dogs receiving 24-hour compression remained paraparetic 5-7 days, with bladder dysfunction for 7-10 days and tail dysfunction persisting for 4 weeks. The dogs with compression for 1 week were paraparetic (Tarlov Grade 2 or 3) and incontinent during the duration of cauda equina compression. They recovered to walking by 1 week and Tarlov Grade 5 with bladder and tail control at the time of euthanasia. Immediately after compression, all five groups demonstrated at least 50% deterioration of the posterior tibial nerve evoked potential amplitudes.(ABSTRACT TRUNCATED AT 250 WORDS)

  18. Nanofibrous nerve conduit-enhanced peripheral nerve regeneration.

    PubMed

    Jiang, Xu; Mi, Ruifa; Hoke, Ahmet; Chew, Sing Yian

    2014-05-01

    Fibre structures represent a potential class of materials for the formation of synthetic nerve conduits due to their biomimicking architecture. Although the advantages of fibres in enhancing nerve regeneration have been demonstrated, in vivo evaluation of fibre size effect on nerve regeneration remains limited. In this study, we analyzed the effects of fibre diameter of electrospun conduits on peripheral nerve regeneration across a 15-mm critical defect gap in a rat sciatic nerve injury model. By using an electrospinning technique, fibrous conduits comprised of aligned electrospun poly (ε-caprolactone) (PCL) microfibers (981 ± 83 nm, Microfiber) or nanofibers (251 ± 32 nm, Nanofiber) were obtained. At three months post implantation, axons regenerated across the defect gap in all animals that received fibrous conduits. In contrast, complete nerve regeneration was not observed in the control group that received empty, non-porous PCL film conduits (Film). Nanofiber conduits resulted in significantly higher total number of myelinated axons and thicker myelin sheaths compared to Microfiber and Film conduits. Retrograde labeling revealed a significant increase in number of regenerated dorsal root ganglion sensory neurons in the presence of Nanofiber conduits (1.93 ± 0.71 × 10(3) vs. 0.98 ± 0.30 × 10(3) in Microfiber, p < 0.01). In addition, the compound muscle action potential (CMAP) amplitudes were higher and distal motor latency values were lower in the Nanofiber conduit group compared to the Microfiber group. This study demonstrated the impact of fibre size on peripheral nerve regeneration. These results could provide useful insights for future nerve guide designs.

  19. Rectus sheath hematoma: three case reports

    PubMed Central

    Kapan, Selin; Turhan, Ahmet N; Alis, Halil; Kalayci, Mustafa U; Hatipoglu, Sinan; Yigitbas, Hakan; Aygun, Ersan

    2008-01-01

    Introduction Rectus sheath hematoma is an uncommon cause of acute abdominal pain. It is an accumulation of blood in the sheath of the rectus abdominis, secondary to rupture of an epigastric vessel or muscle tear. It could occur spontaneously or after trauma. They are usually located infraumblically and often misdiagnosed as acute abdomen, inflammatory diseases or tumours of the abdomen. Case presentation We reported three cases of rectus sheath hematoma presenting with a mass in the abdomen and diagnosed by computerized tomography. The patients recovered uneventfully after bed rest, intravenous fluid replacement, blood transfusion and analgesic treatment. Conclusion Rectus sheath hematoma is a rarely seen pathology often misdiagnosed as acute abdomen that may lead to unnecessary laparotomies. Computerized tomography must be chosen for definitive diagnosis since ultrasonography is subject to error due to misinterpretation of the images. Main therapy is conservative management. PMID:18221529

  20. Carotid sheath haematoma: a case report.

    PubMed

    Yadav, Jayanthi; Badkur, D S; Arora, Arneet

    2009-10-01

    Carotid sheath haematoma is a rare finding, sometimes the only injury found in cases of manual strangulation without any associated external or internal injury to the neck. One such rare case is reported in an 8 year old female victim where presence of carotid sheath haematoma not only helped to ascertain the cause of death but also helped in the reconstruction of mechanism of infliction of force on the neck. 2009 Elsevier Ltd and Faculty of Forensic and Legal Medicine.

  1. Lipoma arborescens of the biceps tendon sheath.

    PubMed

    White, Eric A; Omid, Reza; Matcuk, George R; Domzalski, Jerome T; Fedenko, Alexander N; Gottsegen, Christopher J; Forrester, Deborah M; Patel, Dakshesh B

    2013-10-01

    Lipoma arborescens, described as lipomatous infiltration and distention of synovial villi resulting in a frond-like appearance, most frequently affects the suprapatellar recess of the knee. While there have been reports of this entity involving the upper extremity joints, bursa, and tendon sheaths, we present the first reported case of lipoma arborescens isolated to the biceps tendon sheath. We describe imaging and histologic findings with clinical correlation.

  2. Dust particle dynamics in magnetized plasma sheath

    SciTech Connect

    Davoudabadi, M.; Mashayek, F.

    2005-07-15

    In this paper, the structure of a plasma sheath in the presence of an oblique magnetic field is investigated, and dynamics of a dust particle embedded in the sheath is elaborated. To simulate the sheath, a weakly collisional two-fluid model is implemented. For various magnitudes and directions of the magnetic field and chamber pressures, different plasma parameters including the electron and ion densities, ion flow velocity, and electric potential are calculated. A complete set of forces acting on the dust particle originating from the electric field in the sheath, the static magnetic field, gravity, and ion and neutral drags is taken into account. Through the trapping potential energy, the particle stable and unstable equilibria are studied while the particle is stationary inside the sheath. Other features such as the possibility of the dust levitation and trapping in the sheath, and the effect of the Lorentz force on the charged dust particle motion are also examined. An interesting feature is captured for the variation of the particle charge as a function of the magnetic field magnitude.

  3. Protective sheath for a continuous measurement thermocouple

    DOEpatents

    Phillippi, R.M.

    1991-12-03

    Disclosed is a protective thermocouple sheath of a magnesia graphite refractory material for use in continuous temperature measurements of molten metal in a metallurgical ladle and having a basic slag layer thereon. The sheath includes an elongated torpedo-shaped sheath body formed of a refractory composition and having an interior borehole extending axially therethrough and adapted to receive a thermocouple. The sheath body includes a lower end which is closed about the borehole and forms a narrow, tapered tip. The sheath body also includes a first body portion integral with the tapered tip and having a relatively constant cross section and providing a thin wall around the borehole. The sheath body also includes a second body portion having a relatively constant cross section larger than the cross section of the first body portion and providing a thicker wall around the borehole. The borehole terminates in an open end at the second body portion. The tapered tip is adapted to penetrate the slag layer and the thicker second body portion and its magnesia constituent material are adapted to withstand chemical attack thereon from the slag layer. The graphite constituent improves thermal conductivity of the refractory material and, thus, enhances the thermal responsiveness of the device. 4 figures.

  4. Protective sheath for a continuous measurement thermocouple

    DOEpatents

    Phillippi, R. Michael

    1991-01-01

    Disclosed is a protective thermocouple sheath of a magnesia graphite refractory material for use in continuous temperature measurements of molten metal in a metallurgical ladle and having a basic slag layer thereon. The sheath includes an elongated torpedo-shaped sheath body formed of a refractory composition and having an interior borehole extending axially therethrough and adapted to receive a thermocouple. The sheath body includes a lower end which is closed about the borehole and forms a narrow, tapered tip. The sheath body also includes a first body portion integral with the tapered tip and having a relatively constant cross section and providing a thin wall around the borehole. The sheath body also includes a second body portion having a relatively constant cross section larger than the cross section of the first body portion and providing a thicker wall around the borehole. The borehole terminates in an open end at the second body portion. The tapered tip is adapted to penetrate the slag layer and the thicker second body portion and its magnesia constituent material are adapted to withstand chemical attack thereon from the slag layer. The graphite constituent improves thermal conductivity of the refractory material and, thus, enhances the thermal responsiveness of the device.

  5. Protective sheath for a continuous measurement thermocouple

    SciTech Connect

    Phillippi, R.M.

    1991-12-03

    Disclosed is a protective thermocouple sheath of a magnesia graphite refractory material for use in continuous temperature measurements of molten metal in a metallurgical ladle and having a basic slag layer thereon. The sheath includes an elongated torpedo-shaped sheath body formed of a refractory composition and having an interior borehole extending axially therethrough and adapted to receive a thermocouple. The sheath body includes a lower end which is closed about the borehole and forms a narrow, tapered tip. The sheath body also includes a first body portion integral with the tapered tip and having a relatively constant cross section and providing a thin wall around the borehole. The sheath body also includes a second body portion having a relatively constant cross section larger than the cross section of the first body portion and providing a thicker wall around the borehole. The borehole terminates in an open end at the second body portion. The tapered tip is adapted to penetrate the slag layer and the thicker second body portion and its magnesia constituent material are adapted to withstand chemical attack thereon from the slag layer. The graphite constituent improves thermal conductivity of the refractory material and, thus, enhances the thermal responsiveness of the device. 4 figures.

  6. How to Patch Active Plasma and Collisionless Sheath: Practical Guide

    SciTech Connect

    Kaganovich, Igor D.

    2002-08-22

    Most plasmas have a very thin sheath compared with the plasma dimension. This necessitates separate calculations of the plasma and sheath. The Bohm criterion provides the boundary condition for calculation of plasma profiles. To calculate sheath properties, a value of electric field at the plasma-sheath interface has to be specified in addition to the Bohm criterion. The value of the boundary electric field and robust procedure to approximately patch plasma and collisionless sheath with a very good accuracy are reported.

  7. Reexcision Perineural Invasion and Epithelial Sheath Neuroma Possibly on a Spectrum of Postinjury Reactive Hyperplasia Mediated by IL-6.

    PubMed

    Wang, James Y; Nuovo, Gerard; Kline, Mitchell; Magro, Cynthia M

    2017-01-01

    Epithelial sheath neuroma is a rarely recognized but established entity in the medical literature. First described in 2000 by Requena et al, there have only been 7 published cases to date, mostly in female patients and presenting as symptomatic solitary lesions on the back without a known history of trauma. In 2006, Beer et al described and reviewed a dozen cases in which epithelial sheath neuroma-like features were seen in the advent of a surgical procedure, which was termed "re-excision perineural invasion" and attributed to possible eccrine duct implantation during surgery. Our case is a 66-year-old male patient who underwent an excision of a melanocytic neoplasm in which a reactive epithelial sheath neuroma was incidentally discovered in the excision specimen, adjacent to the biopsy site cicatrix. Histologically, there was benign cutaneous nerve hyperplasia with a proliferation of squamous epithelium in intimate apposition to the nerve bundles in the superficial dermis. We postulate that the process active in the formation of re-excision perineural invasion is the same as in epithelial sheath neuroma and that minor trauma not appreciable on histologic examination is responsible in the latter entity. We performed IL-6 staining and documented that IL-6 was upregulated at the interface of the nerve and reactive epithelium, but was absent in nerves distant from the site of surgery, suggesting that IL-6 may be essential to the lesion's development. The recognition of reactive epithelial sheath neuroma including the subcategory of re-excision perineural invasion is crucial for the dermatopathologist to prevent mislabeling this reactive entity as a perineural squamous cell carcinoma, which has clinical consequences for the patient such as wider re-excision and radiation treatment. Additionally, we have identified a potential pathophysiologic basis for this lesion.

  8. Case Control Study of Type II Decompression Sickness Associated with Patent Foramen Ovale in Experimental No-Decompression Dives

    DTIC Science & Technology

    2010-05-01

    DECOMPRESSION SICKNESS ASSOCIATED WITH PATENT FORAMEN OVALE IN EXPERIMENTAL NO-DECOMPRESSION DIVES Authors: Navy Experimental Diving Unit G. W. Latson...08 NO. 11. TITLE (Include Security Classification) (U) Case Control Study of Type II Decompression Sickness Associated with Patent Foramen Ovale in...reverse if necessary 17. COSATI CODES and identify by block number) FIELD GROUP SUB-GROUP Decompression sickness, DCS, DCI, patent foramen ovale , PFO

  9. Diffusion tensor MRI of spinal decompression sickness

    PubMed Central

    Hutchinson, Elizabeth B.; Sobakin, Aleksey S.; Meyerand, Mary E.; Eldridge, Marlowe; Ferrazzano, Peter

    2013-01-01

    In order to develop more sensitive imaging tools for clinical use and basic research of spinal decompression sickness (DCS), we used diffusion tensor MRI (DTI) validated by histology to assess DCS-related tissue injury in sheep spinal cords. DTI is based on the measurement of water diffusion indices, including fractional anisotropy (FA) and mean diffusion (MD) to detect tissue microstructural abnormalities. In this study, we measured FA and MD in white and gray matter spinal cord regions in samples taken from sheep following hyperbaric exposure to 60–132 fsw and 0–180 minutes of oxygen pre-breathing treatment before rapid decompression. The main finding of the study was that decompression from >60 fsw resulted in reduced FA that was associated with cell death and disrupted tissue microstructure in spinal cord white matter tracts. Additionally, animals exposed to prolonged oxygen pre-breathing prior to decompression demonstrated reduced MD in spinal cord gray matter regions regardless of dive depth. To our knowledge, this is the first study to demonstrate the utility of DTI for the investigation of DCS-related injury and to define DTI biomarkers of spinal DCS. PMID:23397865

  10. Diffusion tensor MRI of spinal decompression sickness.

    PubMed

    Hutchinson, Elizabeth B; Sobakin, Aleksey S; Meyerand, Mary E; Eldridge, Marlowe; Ferrazzano, Peter

    2013-01-01

    In order to develop more sensitive imaging tools for clinical use and basic research of spinal decompression sickness (DCS), we used diffusion tensor MRI (DTI) validated by histology to assess DCS-related tissue injury in sheep spinal cords. DTI is based on the measurement of water diffusion indices, including fractional anisotropy (FA) and mean diffusion (MD) to detect tissue microstructural abnormalities. In this study, we measured FA and MD in white and gray matter spinal cord regions in samples taken from sheep following hyperbaric exposure to 60-132 fsw and 0-180 minutes of oxygen pre-breathing treatment before rapid decompression. The main finding of the study was that decompression from >60 fsw resulted in reduced FA that was associated with cell death and disrupted tissue microstructure in spinal cord white matter tracts. Additionally, animals exposed to prolonged oxygen pre-breathing prior to decompression demonstrated reduced MD in spinal cord gray matter regions regardless of dive depth. To our knowledge, this is the first study to demonstrate the utility of DTI for the investigation of DCS-related injury and to define DTI biomarkers of spinal DCS.

  11. Postsurgical decompression and immediate elemental feeding.

    PubMed

    Moss, G

    1977-05-01

    The paralytic ileus, poor nutritional state, and related complications that often develop following serious serious abdominal surgery have traditionally been accepted as unavoidable. Now, a nasogastric decompression and feeding tube is availabe that usually prevents paralytic ileus and also provides a complete liquid diet starting immedicately after the operation, thus speeding wound healing and recivery.

  12. A Pottery Electric Kiln Using Decompression

    NASA Astrophysics Data System (ADS)

    Naoe, Nobuyuki; Yamada, Hirofumi; Nakayama, Tetsuo; Nakayama, Minoru; Minamide, Akiyuki; Takemata, Kazuya

    This paper presents a novel type electric kiln which fires the pottery using the decompression. The electric kiln is suitable for the environment and the energy saving as the pottery furnace. This paper described the baking principle and the baking characteristic of the novel type electric kiln.

  13. Decompression Sickness Risk Versus Time and Altitude

    DTIC Science & Technology

    1993-11-01

    M, Wiegman J, Pilmanis exposure at 22,500 ft (Fig. 1-2) should raise AA. Prebreathe enhancement with concern since that level of decompression is...Andrew A. P11manis in a research phyniologist 2. Fischer MO, Wiegman JF, McLean SA, Olson Andrew A. ihi ish resiarch poycioo SRM. Evaluation of four

  14. [Electrophysiological monitoring of cranial motor nerves (V, VII, IX, X, XI, XII)].

    PubMed

    Lefaucheur, J-P; Neves, D O; Vial, C

    2009-04-01

    In various neurosurgical operations, there is a risk of cranial nerve lesion that can be avoided or minimized with intraoperative electrophysiological monitoring. Regarding motor function of the cranial nerves, stimulodetection techniques are used, including electrical stimulation of nerve trunks and electromyographic recording of evoked motor responses. These techniques can be used for monitoring the trigeminal nerve (Vth cranial nerve), facial nerve (VIIth), glossopharyngeal nerve (IXth), pneumogastric nerve (Xth), spinal accessory nerve (XIth), and hypoglossal nerve (XIIth), in particular during surgical removal of tumors of the cerebellopontine angle or skull base. When beginning an operation, electrical stimulation is only used to identify the nerve structures. As removal of the tumor progresses, the goal is to verify that a surgical injury to the nerve is avoided by looking for the absence of any change regarding amplitude, morphology, and latency of motor responses. Intraoperative electromyographic monitoring can also be applied during the surgical treatment of primary hemifacial spasm by microvascular decompression. An effective decompression is usually associated with the disappearance of "lateral spread" motor responses to facial nerve branch stimulation. Therefore, the intraoperative disappearance of the lateral spread responses can be considered a predictive factor of good postoperative clinical outcome, even if this assertion remains a matter of debate.

  15. MRI of the Trigeminal Nerve in Patients With Trigeminal Neuralgia Secondary to Vascular Compression.

    PubMed

    Hughes, Marion A; Frederickson, Andrew M; Branstetter, Barton F; Zhu, Xiao; Sekula, Raymond F

    2016-03-01

    Trigeminal neuralgia is a debilitating facial pain disorder, frequently caused by vascular compression of the trigeminal nerve. Vascular compression that results in trigeminal neuralgia occurs along the cisternal segment of the nerve. Imaging combined with clinical information is critical to correctly identify patients who are candidates for microvascular decompression. The purpose of this article is to review trigeminal nerve anatomy and to provide strategies for radiologists to recognize important MRI findings in patients with trigeminal neuralgia.

  16. Interactions of Glial Proteins from the Regenerating Goldfish (C. auratus) Optic Nerve with Retinotectal Axons,

    DTIC Science & Technology

    1988-06-01

    regenerating goldfish optic nerve with retinotectal.. 12. PERSONAL AUTHOR(S) Michael A. Deaton, Susan E. Bock, and John A. Freeman 13a. TYPE OF REPORT...nerve sheath cells during development. Soc Neurosci 1983; 9: Abstr No. 17.33. 26. Ignatius MJ, Gebicke- Harter PJ, Skene JHP, Schilling JW, Weisgraber

  17. The Effect of Temperature on Decompression and Decompression Sickness Risk: A Critical Review

    DTIC Science & Technology

    2004-09-01

    DECOMPRESSION AND DECOMPRESSION SICKNESS RISK: A CRITICAL REVIEW Charles B. Toner, MD Robert Ball, MD Bureau of Medicine and Surgery Department of...SICKNESS RISK: A CRITICAL REVIEW Charles B. Toner, MD Robert Ball, MD Bureau of Medicine and Surgery Department of the Navy Washington, DC 20372-5120...of Medicine and Surgery BUMED (Med-02) 2300 E. Street, N.W. 11. SPONSOR/MONITOR’S REPORT Washington, DC 20372-5300 NUMBER(S) DN241126 12. DISTRIBUTION

  18. Facial nerve paralysis after cervical traction.

    PubMed

    So, Edmund Cheung

    2010-10-01

    Cervical traction is a frequently used treatment in rehabilitation clinics for cervical spine problems. This modality works, in principle, by decompressing the spinal cord or its nerve roots by applying traction on the cervical spine through a harness placed over the mandible (Olivero et al., Neurosurg Focus 2002;12:ECP1). Previous reports on treatment complications include lumbar radicular discomfort, muscle injury, neck soreness, and posttraction pain (LaBan et al., Arch Phys Med Rehabil 1992;73:295-6; Lee et al., J Biomech Eng 1996;118:597-600). Here, we report the first case of unilateral facial nerve paralysis developed after 4 wks of intermittent cervical traction therapy. Nerve conduction velocity examination revealed a peripheral-type facial nerve paralysis. Symptoms of facial nerve paralysis subsided after prednisolone treatment and suspension of traction therapy. It is suspected that a misplaced or an overstrained harness may have been the cause of facial nerve paralysis in this patient. Possible causes were (1) direct compression by the harness on the right facial nerve near its exit through the stylomastoid foramen; (2) compression of the right external carotid artery by the harness, causing transient ischemic injury at the geniculate ganglion; or (3) coincidental herpes zoster virus infection or idiopathic Bell's palsy involving the facial nerve.

  19. Are sheath folds late stage flanking structures?

    NASA Astrophysics Data System (ADS)

    Reber, Jacqueline E.; Dabrowski, Marcin; Schmid, Daniel W.

    2010-05-01

    Sheath folds can be described as highly non-cylindrical folds or as cone shaped with a rounded apex. A cross section of a sheath fold perpendicular to its elongation direction shows usually an elliptical shape. Sheath folds can be observed in nature within a wide range of materials and across many orders of size magnitude. A classification scheme has been developed by Alsop and Holdsworth (Journal of Structural Geology, 2006) which divides sheath folds into different categories depending on the ratio of the aspect ratio of the innermost and outermost "ring". Different initial conditions such as rigid objects and precursor folds formed through buckling were suggested as a trigger for the development of sheath folds. However, in nature sheath folds can also be observed where no rigid objects or precursor folds can be seen. In such cases we propose weak objects or zones as possible activators. According to this approach sheath folds represent a late stage of flanking structures. To simulate the weak zone we use an infinitely weak elliptical inclusion embedded in a homogeneous matrix. Planar markers such as bedding or foliation make the sheath geometry visible. To test the impact of the initial shape of the weak zone on the formation of the sheath folds the aspect ratio of the slip ellipse is changed systematically. As the geometry of sheath folds is truly three dimensional we use a 3D analytical model to investigate their formation. The model is based on an adapted internal and external Eshelby solution (Eshelby, Proceedings of the Royal Society of London series a-Mathematical and Physical Sciences, 1957 and 1959) for viscous rheologies and elliptical inclusions described in Exner and Dabrowski (Journal of Structural Geology, 2010 (submitted)). The ellipse as well as the matrix has linear viscous, isotropic, incompressible material properties. To analyze the cross-section the calculated folds are cut perpendicular to the simple shear stretching direction while the

  20. Ethmoidectomy decompression for the treatment of Graves' optic neuropathy.

    PubMed

    Hurwitz, J J; Freeman, J L; Eplett, C J; Fliss, D M; Avram, D R

    1992-10-01

    When orbital decompression becomes necessary in Graves' optic neuropathy, medial wall decompression is a necessary component of the decompression procedure. The ethmoidectomy approach allows more direct visualization of the posterior ethmoids and sphenoids to effect maximum decompression. This is particularly important in cases in which computed tomography shows the medial rectus muscle to be enlarged posteriorly in the orbit. The procedure provides excellent visualization of the medial rectus. As with any medial wall decompression procedure, postoperative restriction of horizontal motility is a frequent complication, often necessitating more than one subsequent operation. The authors describe their experience with the procedure in 25 patients with Graves' optic neuropathy.

  1. The Anatomic Relationship of the Tibial Nerve to the Common Peroneal Nerve in the Popliteal Fossa: Implications for Selective Tibial Nerve Block in Total Knee Arthroplasty

    PubMed Central

    Silverman, Eric R.; Vydyanathan, Amaresh; Gritsenko, Karina; Shaparin, Naum; Singh, Nair; Downie, Sherry A.

    2017-01-01

    Background. A recently described selective tibial nerve block at the popliteal crease presents a viable alternative to sciatic nerve block for patients undergoing total knee arthroplasty. In this two-part investigation, we describe the effects of a tibial nerve block at the popliteal crease. Methods. In embalmed cadavers, after the ultrasound-guided dye injection the dissection revealed proximal spread of dye within the paraneural sheath. Consequentially, in the clinical study twenty patients scheduled for total knee arthroplasty received the ultrasound-guided selective tibial nerve block at the popliteal crease, which also resulted in proximal spread of local anesthetic. A sensorimotor exam was performed to monitor the effect on the peroneal nerve. Results. In the cadaver study, dye was observed to spread proximal in the paraneural sheath to reach the sciatic nerve. In the clinical observational study, local anesthetic was observed to spread a mean of 4.7 + 1.9 (SD) cm proximal to popliteal crease. A negative correlation was found between the excess spread of local anesthetic and bifurcation distance. Conclusions. There is significant proximal spread of local anesthetic following tibial nerve block at the popliteal crease with possibility of the undesirable motor blocks of the peroneal nerve. PMID:28260964

  2. INDIRECT ARTHROSCOPIC DECOMPRESSION OF SPINOGLENOID CYST WITH SUPRASCAPULAR NEUROPATHY: REPORT OF TWO CASES AND LITERATURE REVIEW

    PubMed Central

    Fernandes, Marcos Rassi; Fernandes, Rui José

    2015-01-01

    Suprascapular nerve compression is rare and should be considered in the differential diagnosis of patients with shoulder pain and external rotation deficit. Spinoglenoidal cysts may cause compression, and posterosuperior glenoid labrum lesions are the most likely hypothesis to explain their appearance. Magnetic resonance imaging and electromyography define the diagnosis. Indirect arthroscopic decompression of the cyst and repair of the glenoid labrum enable complete neurological recovery. The authors report two cases of isolated paralysis of the infraspinatus muscle caused by compression due to spinoglenoidal cysts that were treated by means of arthroscopy, and present the pre and postoperative assessments. PMID:27022558

  3. Fetal anatomy of the human carotid sheath and structures in and around it.

    PubMed

    Miyake, Naritomo; Hayashi, Shogo; Kawase, Tetsuaki; Cho, Baik Hwan; Murakami, Gen; Fujimiya, Mineko; Kitano, Hiroya

    2010-03-01

    The aim of this study was to find basic rules governing the morphological development of the typical neurovascular sheath. We carried out histological examination of 15 paraffin-embedded mid-term fetuses at 9-25 weeks of gestation (three fetuses each at 9, 12, 15, 20, and 25 weeks). As the result, the vagus nerve showed a high propensity to change its topographical relationship with the common carotid artery (CCA) during 9-20 weeks of gestation: that is, from a primitive ventral course to a final dorsal course. The adventitia of the great arteries, which was distinct from other fascial structures, became evident by 15 weeks. The carotid sheath appeared at and after 20 weeks: it was clearly separated from the prevertebral lamina of the deep cervical fasciae, but fused with the pretracheal lamina covering the strap muscles. Thus the carotid sheath, as well as the topographical relationships of structures within it, seems to become established much later than the prevertebral and pretracheal laminae of the deep cervical fasciae. However, the adventitia of the cervical great arteries consistently becomes evident much earlier than the sheath, and it seems to be regarded as one of the basic components of the fetal deep cervical fasciae.

  4. Human Vagus Nerve Branching in the Cervical Region

    PubMed Central

    Hammer, Niels; Glätzner, Juliane; Feja, Christine; Kühne, Christian; Meixensberger, Jürgen; Planitzer, Uwe; Schleifenbaum, Stefan; Tillmann, Bernhard N.; Winkler, Dirk

    2015-01-01

    Background Vagus nerve stimulation is increasingly applied to treat epilepsy, psychiatric conditions and potentially chronic heart failure. After implanting vagus nerve electrodes to the cervical vagus nerve, side effects such as voice alterations and dyspnea or missing therapeutic effects are observed at different frequencies. Cervical vagus nerve branching might partly be responsible for these effects. However, vagus nerve branching has not yet been described in the context of vagus nerve stimulation. Materials and Methods Branching of the cervical vagus nerve was investigated macroscopically in 35 body donors (66 cervical sides) in the carotid sheath. After X-ray imaging for determining the vertebral levels of cervical vagus nerve branching, samples were removed to confirm histologically the nerve and to calculate cervical vagus nerve diameters and cross-sections. Results Cervical vagus nerve branching was observed in 29% of all cases (26% unilaterally, 3% bilaterally) and proven histologically in all cases. Right-sided branching (22%) was more common than left-sided branching (12%) and occurred on the level of the fourth and fifth vertebra on the left and on the level of the second to fifth vertebra on the right side. Vagus nerves without branching were significantly larger than vagus nerves with branches, concerning their diameters (4.79 mm vs. 3.78 mm) and cross-sections (7.24 mm2 vs. 5.28 mm2). Discussion Cervical vagus nerve branching is considerably more frequent than described previously. The side-dependent differences of vagus nerve branching may be linked to the asymmetric effects of the vagus nerve. Cervical vagus nerve branching should be taken into account when identifying main trunk of the vagus nerve for implanting electrodes to minimize potential side effects or lacking therapeutic benefits of vagus nerve stimulation. PMID:25679804

  5. The onset and rate of myelination in six peripheral and autonomic nerves of the rat.

    PubMed Central

    Schäfer, K; Friede, R L

    1988-01-01

    A light and electron microscopic study was carried out of the numbers of myelinated fibres in 6 nerves of the rat for 7 age groups from birth to 73 weeks. The hypoglossal nerve and the mandibular branch of the facial nerve had short and early myelination periods, essentially complete by the second week. The glossopharyngeal nerve and the sympathetic rami communicantes myelinated late and over a protracted period. Myelination of the rami communicantes continued up to 20 weeks, followed by a marked loss of fibres in the 73 week animals. Intercostal and saphenous nerves had intermediary patterns. There was evidence of subpopulations myelinating at different times. Measurements of myelin sheath thickness showed variations of relative sheath thickness with age, between nerves and for subpopulations of nerves. Late myelination corresponded to relatively thin myelin sheaths. Statistical two-stage-density cluster analysis by computer was used for analysing complex fibre populations. The developmental changes of three subpopulations of the intercostal nerve are documented. Nerves also differed in their rates of axon growth. The increment in axon calibre was small and late for sympathetic fibres. Intercostal and facial nerve fibres had rapid axon growth with different growth rates for subpopulations. PMID:3248966

  6. Ambulation Increases Decompression Sickness in Altitude Exposure

    NASA Technical Reports Server (NTRS)

    Conkin, Johnny; Pollock, N. W.; Natoli, M. J.; Wessel, J. H., III; Gernhardt, M. L.

    2014-01-01

    INTRODUCTION - Exercise accelerates inert gas elimination during oxygen breathing prior to decompression (prebreathe), but may also promote bubble formation and increase the risk of decompression sickness (DCS). The timing, pattern and intensity of exercise are likely critical to the net effect. The NASA Prebreathe Reduction Program (PRP) combined oxygen prebreathe and exercise preceding a 4.3 psi exposure in non-ambulatory subjects (a microgravity analog) to produce two protocols now used by astronauts preparing for extravehicular activity (CEVIS and ISLE). Additional work is required to investigate whether exercise normal to 1 G environments increases the risk of DCS over microgravity simulation. METHODS - The CEVIS protocol was replicated with one exception. Our subjects completed controlled ambulation (walking in place with fixed cadence and step height) during both preflight and at 4.3 psi instead of remaining non-ambulatory throughout. Decompression stress was graded with aural Doppler (Spencer 0-IV scale). Two-dimensional echocardiographic imaging was used to look for left heart gas emboli (the presence of which prompted test termination). Venous blood was collected at three points to correlate Doppler measures of decompression stress with microparticle (cell fragment) accumulation. Fisher Exact Tests compared test and control groups. Trial suspension would occur when DCS risk >15% or grade IV venous gas emboli (VGE) risk >20% (at 70% confidence). RESULTS - Eleven person-trials were completed (9 male, 2 female) when DCS prompted suspension. DCS was greater than in CEVIS trials (3/11 [27%] vs. 0/45 [0%], respectively, p=0.03). Statistical significance was not reached for peak grade IV VGE (2/11 [18%] vs. 3/45 [7%], p=0.149) or cumulative grade IV VGE observations per subject-trial (8/128 [6%] vs. 26/630 [4%], p=0.151). Microparticle data were collected for 5/11 trials (3 with DCS outcomes), with widely varying patterns that could not be resolved statistically

  7. Attic construction with sheathing-applied insulation

    SciTech Connect

    Rose, W.B.

    1995-12-31

    Two years of study at a building research laboratory have been applied to cathedralized residential attic construction. Cathedralized attics are rafter-framed or truss-framed attics with flat ceilings in which the insulation is placed against the underside of the roof sheathing rather than on top of the ceiling drywall. The potential benefits of sheathing-applied insulation are considerable and are due to the fact that the attic space becomes part of the conditioned volume. Concern is often expressed that moisture damage may occur in the sheathing. The intent of the current study was to address those concerns. This study allowed an assessment of the performance of cathedralized ceilings, given the following construction variables: (1) ventilation vs. no ventilation, (2) continuous air chute construction vs. stuffed insulation construction, and (3) opens joints in exposed kraft facing vs. taped joints. The results were compared to a concurrent study of the performance of cathedral ceilings with sloped ceiling drywall. The results show that having an air chute that ensures an air gap between the sheathing and the top of the insulation is the critical factor. Ventilation and the taping of joints were minor determinants of the moisture performance of the sheathing. These results are consistent with the results of normal cathedral ceiling construction performance.

  8. L-carnitine alleviates sciatic nerve crush injury in rats: functional and electron microscopy assessments

    PubMed Central

    Avsar, Ümmü Zeynep; Avsar, Umit; Aydin, Ali; Yayla, Muhammed; Ozturkkaragoz, Berna; Un, Harun; Saritemur, Murat; Mercantepe, Tolga

    2014-01-01

    Several studies have demonstrated that L-carnitine exhibits neuroprotective effects on injured sciatic nerve of rats with diabetes mellitus. It is hypothesized that L-carnitine exhibits neuroprotective effects on injured sciatic nerve of rats. Rat sciatic nerve was crush injured by a forceps and exhibited degenerative changes. After intragastric administration of 50 and 100 mg/kg L-carnitine for 30 days, axon area, myelin sheath area, axon diameter, myelin sheath diameter, and numerical density of the myelinated axons of injured sciatic nerve were similar to normal, and the function of injured sciatic nerve also improved significantly. These findings suggest that L-carnitine exhibits neuroprotective effects on sciatic nerve crush injury in rats. PMID:25206754

  9. Injection versus Decompression for Carpal Tunnel Syndrome-Pilot trial (INDICATE-P)-protocol for a randomised feasibility study.

    PubMed

    Mason, Will; Ryan, Daniel; Khan, Asif; Kerr, Hui-Ling; Beard, David; Cook, Jonathan; Rombach, Ines; Cooper, Cushla

    2017-01-01

    Carpal tunnel syndrome (CTS) is the commonest peripheral nerve disorder in the UK, with over 52,996 carpal tunnel decompressions performed in 2011. By 2030, this figure is estimated to double. Whilst evidence supports conservative measures for mild symptoms, and early surgery for severe symptoms, controversy remains over the most appropriate management for patients that present with moderate disease, with regard to early surgery or late surgery following steroid injection. Injection versus Decompression for Carpal Tunnel Syndrome-Pilot trial (INDICATE-P) is a feasibility study for a multicentre, randomised controlled trial (INDICATE) to determine whether patients over the age of 18 with moderate CTS should undergo early surgical decompression of the median nerve or a single steroid injection (followed by later surgery if required). INDICATE-P is a feasibility study for an open (non-blinded) randomised controlled pilot trial. Eligible participants will be adults with a clinical diagnosis of moderate CTS. This is defined as symptoms disturbing sleep or restricting activities of daily living or work, despite a 2-week trial of night splints. Participants will be randomised to one of two possible interventions: surgical decompression or a single steroid injection (followed by surgery later if required). Clinical outcome measures will be captured by postal questionnaire at 1, 3, 6 and 12 months post-randomisation. In order to improve the study design for the main INDICATE trial, feasibility data will also be collected to identify difficulties in recruitment and retention, to gain patient feedback on questionnaires and to confirm the suitability of the proposed outcome measures. The INDICATE-P feasibility study will contribute to the design and execution of the INDICATE trial, which will seek to assess the safety and effectiveness of two approaches to treatment for patients over 18 years of age with moderate CTS: early carpal tunnel decompression or a single steroid

  10. A simple protocol for paraffin-embedded myelin sheath staining with osmium tetroxide for light microscope observation.

    PubMed

    Di Scipio, Federica; Raimondo, Stefania; Tos, Pierluigi; Geuna, Stefano

    2008-07-01

    Experimental investigation of peripheral nerve fiber regeneration is attracting more and more attention among both basic and clinical researchers. Assessment of myelinated nerve fiber morphology is a pillar of peripheral nerve regeneration research. The gold standard for light microscopic imaging of myelinated nerve fibers is toluidine blue staining of resin-embedded semithin sections. However, many researchers are unaware that the dark staining of myelin sheaths typically produced by this procedure is due to osmium tetroxide postfixation and not due to toluidine blue. In this article, we describe a simple pre-embedding protocol for staining myelin sheaths in paraffin-embedded nerve specimens using osmium tetroxide. The method involves immersing the specimen in 2% osmium tetroxide for 2 h after paraformaldehyde fixation, followed by routine dehydration and paraffin embedding. Sections can then be observed directly under the microscope or counterstained using routine histological methods. Particularly good results were obtained with Masson's trichrome counterstain, which permits the imaging of connective structures in nerves that are not detectable in toluidine blue-stained resin sections. Finally, we describe a simple protocol for osmium etching of sections, which makes further immunohistochemical analysis possible on the same specimens. Taken together, our results suggest that the protocol described in this article is a valid alternative to the conventional resin embedding-based protocol: it is much cheaper, can be adopted by any histological laboratory, and allows immunohistochemical analysis to be conducted.

  11. Polarization force-induced changes in the dust sheath formation

    SciTech Connect

    Mayout, Saliha; Bentabet, Karima; Tribeche, Mouloud

    2015-09-15

    The modifications arising in the dusty plasma sheath structure due to the presence of polarization forces acting on the dust grains are investigated. The corresponding appropriate Bohm criterion for sheath formation is obtained. It is found that the critical Mach number, beyond which the dusty plasma electrostatic sheath sets in, decreases whenever the polarization effects become important. In addition, when the polarization force dominates over the electrical one, the dust plasma sheath cannot set in. This happens whenever the dust grain size exceeds a critical threshold. Moreover, the sheath electrostatic potential-gradient becomes abruptly steep, and the sheath thickness becomes broader as the polarization force effects strengthen.

  12. Placement of Teflon Sponges in Microvascular Decompression Procedure for Treatment of Hemifacial Spasm.

    PubMed

    Nan-Xiang, Xiong; Lv-An, Chen; Zhi-Jun, Chen; Hong-Yang, Zhao

    2016-07-01

    Background Hemifacial spasm (HFS) is generally treated by microvascular decompression (MVD). Inadequate separation of vessel and nerve or adhesive inflammation surrounding the nerve root may cause recurrence. Objective To explore a method to reduce the incidence of adhesions and to ensure sufficient separation of the offending vessel and nerve during MVD. Methods Fifty-one patients diagnosed with HFS were studied. During the MVD procedure, Teflon sponges were placed between the offending vessels and medulla oblongata to push compressing vessels away from the facial nerve without contacting the nerve. Results Our method of placement of the Teflon sponge effectively shifts the compressing artery and ensures that both the Teflon sponge and offending vessels do not contact the root exit zone. This method also ensures that the Teflon sponge is fixed in place. Conclusion The technique described for the treatment of HFS provides an effective, safe, and durable resolution to patient symptoms that minimizes surgical complications and may be useful in treating HFS. Georg Thieme Verlag KG Stuttgart · New York.

  13. [Percutaneous laser disc decompression for lumbar discogenic radicular pain].

    PubMed

    Duarte, R; Costa, J C

    2012-01-01

    The aim of our study was to directly evaluate the effectiveness of percutaneous laser disc decompression (PLDD) for treatment of lumbar discogenic radicular pain. From June 2006 through July 2009, 205 patients with contained disc herniation demonstrated on computed tomography (CT) or magnetic resonance, concordance between the radicular pain and the nerve root compressed by the herniated disc, neurological findings referring to a single nerve root and no improvement after conservative therapy for a minimum of six weeks were enrolled. All patients were treated with PLDD under CT guidance and local anaesthesia. Follow-up was scheduled at 1, 2 days, 3, 6 months. Subsequent follow-ups at 12, 24 and 36 months were carried out through visits or by telephone. Clinical outcome was quantified using the MacNab criteria. The age of patients ranged from 27 to 78 years (mean 58±11 years). The levels of involvement were 18 cases at L3-L4, 123 cases at L4-L5 and 64 cases at L5-S1. Using the MacNab criteria, the results were as follows: 67% (n=137) showed a good outcome and 9% (n=18) a fair outcome. There were no serious complications in our series. PLDD is effective treatment for lumbar discogenic radicular pain, associated with only minimal discomfort to the patient. This minimally invasive technique is a valid alternative for those patients not responding to conservative medical treatment, allowing in many cases to obviate the need of spine surgery. Copyright © 2010 SERAM. Published by Elsevier Espana. All rights reserved.

  14. Safety of microvascular decompression for elderly patients with trigeminal neuralgia.

    PubMed

    Amagasaki, Kenichi; Watanabe, Saiko; Naemura, Kazuaki; Shono, Naoyuki; Nakaguchi, Hiroshi

    2016-02-01

    The present study compared the safety and efficacy of microvascular decompression (MVD) in groups of elderly patients and non-elderly patients with medically refractory trigeminal neuralgia (TN) and collected detailed perioperative data. Retrospective analysis of clinical data was performed in 99 patients who underwent MVD from May 2012 to June 2015. The outcome data from 27 MVD operations for 27 patients aged 70-80 years (mean 74.6 years) were compared with 72 MVD operations with 72 patients aged 25-69 years (mean 55.7 years). Preoperative comorbidities were recorded and postoperative worsening comorbidities and non-neurological complications were evaluated at discharge. Efficacy of the surgery and neurological complications were evaluated in July 2015. No decrease in activity of daily living was found in any patient. Complete pain relief without medication was achieved in 77.8% and partial pain relief in 14.8% in the elderly group, and 83.3% and 9.7%, respectively, in the non-elderly group (p=0.750). Permanent neurological complication was not observed in the elderly group, whereas Vth nerve and VIIIth nerve complications were observed in the non-elderly group. Rates of preoperative multiple comorbidities and of cardiovascular comorbidity were significantly higher in the elderly group (p<0.01). Worsening comorbidity and new pathology at discharge were mainly hypertension in both groups, but glaucoma attack and asthma attack were observed in the elderly group. All pathologies were successfully managed. MVD for elderly patients with TN can be achieved safely with careful perioperative management. Information of comorbidity should be shared with all staff involved in the treatment, who should work as a team to avoid worsening comorbidity. The possibility of unpredictable events in the elderly patients should always be considered. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Echo imaging in decompression sickness research

    NASA Astrophysics Data System (ADS)

    Olson, Robert M.; Pilmanis, Andrew A.; Scoggins, Terrell E.

    For two decades a noninvasive, ultrasonic Doppler device has been available to detect the bubbles associated with decompression sickness (DCS) in humans. Although it is of undisputed value in DCS research, this device has some limitations. First, the signals from the bubbles produce sounds rather than visual images. Second, the bubbles have to be in motion and thus in the vascular system to be detected. Finally, no estimate of bubble size is easily available. A new type of ultrasonic device which overcomes these limitations has recently become available. This device was used to examine four decompressed subjects and it was found that this new device produces visual images of bubbles. These bubbles can be seen even if they are outside the vascular system and thus stationary. A preliminary attempt at estimating bubble size with this device is presented.

  16. Decompressive Hemicraniectomy in Acute Neurological Diseases.

    PubMed

    Crudele, Angela; Shah, Syed Omar; Bar, Barak

    2016-10-01

    Increased intracranial pressure (ICP) secondary to severe brain injury is common. Increased ICP is commonly encountered in malignant middle cerebral artery ischemic stroke, traumatic brain injury, subarachnoid hemorrhage, and intracerebral hemorrhage. Multiple interventions-both medical and surgical-exist to manage increased ICP. Medical management is used as first-line therapy; however, it is not always effective and is associated with significant risks. Decompressive hemicraniectomy is a surgical option to reduce ICP, increase cerebral compliance, and increase cerebral blood perfusion when medical management becomes insufficient. The purpose of this review is to provide an up-to-date summary of the use of decompressive hemicraniectomy for the management of refractory elevated ICP in malignant middle cerebral artery ischemic stroke, traumatic brain injury, subarachnoid hemorrhage, and intracerebral hemorrhage. © The Author(s) 2015.

  17. Physiological Correlates and Predictors of Functional Recovery After Chiasmal Decompression.

    PubMed

    Raz, Noa; Bick, Atira S; Klistorner, Alexander; Spektor, Sergey; Reich, Daniel S; Ben-Hur, Tamir; Levin, Netta

    2015-12-01

    The intrinsic abilities and limits of the nervous system to repair itself after damage may be assessed using a model of optic chiasmal compression, before and after a corrective surgical procedure. Visual fields (VFs), multifocal visual evoked potentials (mfVEP), retinal nerve fiber layer (RNFL) thickness, and diffusion tensor imaging were used to evaluate a patient before and after removal of a meningioma compressing the chiasm. Normally sighted individuals served as controls. The advantage of each modality to document visual function and predict postoperative outcome (2-year follow-up) was evaluated. Postsurgery visual recovery was best explained by critical mass of normally conducting fibers and not associated with average conduction amplitudes. Recovered VF was observed in quadrants in which more than 50% of fibers were identified, characterized by intact mfVEP latencies, but severely reduced amplitudes. Recovery was evident despite additional reduction of RNFL thickness and abnormal optic tract diffusivity. The critical mass of normally conducting fibers was also the best prognostic indicator for functional outcome 2 years later. Our results highlight the ability of the remaining normally conductive axons to predict visual recovery after decompression of the optic chiasm. The redundancy in anterior visual pathways may be explained, neuroanatomically, by overlapping receptive fields.

  18. Oxygen Equipment and Rapid Decompression Studies

    DTIC Science & Technology

    1979-03-01

    of the aerodynamic ( Venturi ) effect . Blockley and Hanifan (5) describe this phenomenon in large (bomber) aircraft. The removal of doors and hatches...tudes as a result of increased descent time, the possibility of the Venturi effect , and additional physiological insults of decompression to 15,240 m...deSteiguer EFFECTIVENESS OF A PAPER CUP AS AN AID TO PROVIDING 94 OXYGEN TO LARYNCECTOMEE PASSENGERS by E. B. McFadden PHYSIOLOGICAL CONSIDERATIONS AND

  19. Space Flight Decompression Sickness Contingency Plan

    NASA Technical Reports Server (NTRS)

    Dervay, Joseph; Gernhardt, Michael L.; Ross, Charles E.; Hamilton, Douglas; Homick, Jerry L. (Technical Monitor)

    2000-01-01

    The purpose was to develop an enhanced plan to diagnose, treat, and manage decompression sickness (DCS) during extravehicular activity (EVA). This plan is merited by the high frequency of upcoming EVAs necessary to construct and maintain the International Space Station (ISS). The upcoming ISS era will demand a significant increase in EVA. The DCS Risk and Contingency Plan provided a new and improved approach to DCS reporting, treatment, management, and training.

  20. Identifying the Subtle Presentation of Decompression Sickness.

    PubMed

    Alea, Kenneth

    2015-12-01

    Decompression sickness is an inherent occupational hazard that has the possibility to leave its victims with significant long-lasting effects that can potentially impact an aircrew's flight status. The relative infrequency of this hazard within the military flying community along with the potentially subtle presentation of decompression sickness (DCS) has the potential to result in delayed diagnosis and treatment, leading to residual deficits that can impact a patient's daily life or even lead to death. The patient presented in this work was diagnosed with a Type II DCS 21 h after a cabin decompression at 35,000 ft (10,668 m). The patient had been asymptomatic with a completely normal physical/neurological exam following his flight. The following day, he presented with excessive fatigue and on re-evaluation was recommended for hyperbaric therapy, during which his symptoms completely resolved. He was re-evaluated 14 d later and cleared to resume flight duties without further incident. The manifestation of this patient's decompression sickness was subtle and followed an evaluation that failed to identify any focal findings. A high index of suspicion with strict follow-up contributed to the identification of DCS in this case, resulting in definitive treatment and resolution of the patient's symptoms. Determination of the need for hyperbaric therapy following oxygen supplementation and a thorough history and physical is imperative. If the diagnosis is in question, consider preemptive hyperbaric therapy as the benefits of treatment in DCS outweigh the risks of treatment. Finally, this work introduces the future potential of neuropsychological testing for both the diagnosis of DCS as well as assessing the effectiveness of hyperbaric therapy in Type II DCS.

  1. Endothelial dysfunction correlates with decompression bubbles in rats

    PubMed Central

    Zhang, Kun; Wang, Dong; Jiang, Zhongxin; Ning, Xiaowei; Buzzacott, Peter; Xu, Weigang

    2016-01-01

    Previous studies have documented that decompression led to endothelial dysfunction with controversial results. This study aimed to clarify the relationship between endothelial dysfunction, bubble formation and decompression rate. Rats were subjected to simulated air dives with one of four decompression rates: one slow and three rapid. Bubble formation was detected ultrasonically following decompression for two hours, before measurement of endothelial related indices. Bubbles were found in only rapid-decompressed rats and the amount correlated with decompression rate with significant variability. Serum levels of ET-1, 6-keto-PGF1α, ICAM-1, VCAM-1 and MDA, lung Wet/Dry weight ratio and histological score increased, serum NO decreased following rapid decompression. Endothelial-dependent vasodilatation to Ach was reduced in pulmonary artery rings among rapid-decompressed rats. Near all the above changes correlated significantly with bubble amounts. The results suggest that bubbles may be the causative agent of decompression–induced endothelial damage and bubble amount is of clinical significance in assessing decompression stress. Furthermore, serum levels of ET-1 and MDA may serve as sensitive biomarkers with the capacity to indicate endothelial dysfunction and decompression stress following dives. PMID:27615160

  2. Decompression scenarios in a new underground transportation system.

    PubMed

    Vernez, D

    2000-10-01

    The risks of a public exposure to a sudden decompression, until now, have been related to civil aviation and, at a lesser extent, to diving activities. However, engineers are currently planning the use of low pressure environments for underground transportation. This method has been proposed for the future Swissmetro, a high-speed underground train designed for inter-urban linking in Switzerland. The use of a low pressure environment in an underground public transportation system must be considered carefully regarding the decompression risks. Indeed, due to the enclosed environment, both decompression kinetics and safety measures may differ from aviation decompression cases. A theoretical study of decompression risks has been conducted at an early stage of the Swissmetro project. A three-compartment theoretical model, based on the physics of fluids, has been implemented with flow processing software (Ithink 5.0). Simulations have been conducted in order to analyze "decompression scenarios" for a wide range of parameters, relevant in the context of the Swissmetro main study. Simulation results cover a wide range from slow to explosive decompression, depending on the simulation parameters. Not surprisingly, the leaking orifice area has a tremendous impact on barotraumatic effects, while the tunnel pressure may significantly affect both hypoxic and barotraumatic effects. Calculations have also shown that reducing the free space around the vehicle may mitigate significantly an accidental decompression. Numeric simulations are relevant to assess decompression risks in the future Swissmetro system. The decompression model has proven to be useful in assisting both design choices and safety management.

  3. Reversal of dysthyroid optic neuropathy following orbital fat decompression

    PubMed Central

    Kazim, M.; Trokel, S.; Acaroglu, G.; Elliott, A.

    2000-01-01

    AIMS—To document the successful treatment of five patients with dysthyroid optic neuropathy by orbi