Cystic Dumbbell-Shaped C1 Schwannoma with Intracranial Extension and Hydrocephalus.

BACKGROUND: Schwannomas at the craniocervical junction commonly originate from the lower cranial nerves or C1 and C2 nerves. To date, very few cases of C1 schwannomas have been described in the literature, and the majority involve either the intra- or the extradural compartment, but not both. To our knowledge, this report documents the first case of a dumbbell-shaped C1 schwannoma that encompassed both intra- and extradural compartments and was accompanied by hydrocephalus. CASE DESCRIPTION: The patient was admitted to our hospital, where magnetic resonance imaging revealed a tumor at the craniocervical junction, extending from the C1 level of the right first cervical vertebra into the cerebellopontine angle with 2 giant cysts. We removed the tumor by performing a midline posterior craniectomy and cervical laminectomy. Intraoperatively, the tumor was found to originate from the right C1 posterior root. The pathological diagnosis was of a schwannoma. The patient was subsequently discharged without any neurologic deficits. CONCLUSIONS: To our knowledge, we present the first case of a dumbbell-shaped C1 schwannoma with intracranial extensions and accompanying hydrocephalus. The tumor had spread inside and outside the dura, but was safely removed. Our findings in this case emphasize that to achieve safe resection, detailed case-specific preoperative consideration is essential.

Effects of vestibular neurectomy and neural compensation on head movements in patients undergoing vestibular schwannoma resection.

The vestibular system is vital for maintaining balance and stabilizing gaze and vestibular damage causes impaired postural and gaze control. Here we examined the effects of vestibular loss and subsequent compensation on head motion kinematics during voluntary behavior. Head movements were measured in vestibular schwannoma patients before, and then 6 weeks and 6 months after surgical tumor removal, requiring sectioning of the involved vestibular nerve (vestibular neurectomy). Head movements were recorded in six dimensions using a small head-mounted sensor while patients performed the Functional Gait Assessment (FGA). Kinematic measures differed between patients (at all three time points) and normal subjects on several challenging FGA tasks, indicating that vestibular damage (caused by the tumor or neurectomy) alters head movements in a manner that is not normalized by central compensation. Kinematics measured at different time points relative to vestibular neurectomy differed substantially between pre-operative and 6-week post-operative states but changed little between 6-week and > 6-month post-operative states, demonstrating that compensation affecting head kinematics is relatively rapid. Our results indicate that quantifying head kinematics during self-generated gait tasks provides valuable information about vestibular damage and compensation, suggesting that early changes in patient head motion strategy may be maladaptive for long-term vestibular compensation.

Structural Origin and Surgical Complications of Peripheral Schwannomas.

BACKGROUND/AIM: In this study, we investigated the locations and surgical complications of schwannomas. PATIENTS AND METHODS: Data of 130 patients with schwannomas were retrospectively reviewed. Pre- and post-operative neurological symptoms, tumor locations, and nerves of origin (sensory, motor, or mixed) were reviewed. RESULTS: Before surgery, 69 patients had Tinel-like signs, 56 patients had pain, 32 patients had numbness, four patients had motor deficits. After surgery, 20 patients had developed a new neurological deficit; 11 patients had motor deficits, ten patients had sensory deficits, and one patient had both motor and sensory deficits. Most schwannomas occurred in mixed nerves, including the median nerve in 17 patients and tibial nerve in 13 patients. CONCLUSION: The most common site of schwannoma was the median nerve. Although the nerve of origin of the schwannoma could be identified in only 26.0% of cases, the data suggest that schwannomas occur in both sensory and motor nerves.

Peripheral nerve sheath tumors in Neurofibromatosis Type 2: Surgical and histopathologic features.

OBJECTIVE: Management of peripheral nerve sheath tumors (PNST) in Neurofibromatosis Type 2 (NF2) is complicated by frequent involvement of major peripheral nerves and concern that these tumors may be plexiform and/or involve multiple fascicles. Hybrid histologic features of both schwannoma and neurofibroma have been described in NF2-associated tumors, although the incidence of this phenotype in PNSTs is unknown. We sought to define the outcomes of surgery for tumors involving major peripheral nerves in NF2 and identify the rate of hybrid histology in PNSTs. PATIENTS AND METHODS: Functional outcomes of surgery for patients with tumors on major (named) peripheral nerves were recorded. Histopathologic analyses were performed on all available excised tumors. RESULTS: Nineteen operations were performed in 12 patients with NF2, for resection of 28 PNSTs. Among 11 tumors involving major peripheral nerves, 10 involved nerves related to motor function. Presenting symptoms in this group included pain (9) and weakness (4). Median tumor diameter was 3.4 cm (range:2.2-10.3 cm). Gross-total resection was achieved in 10 cases. Motor function was stable/improved in 10 cases but diminished after one case involving a small motor fascicle. All tumors involved a single fascicle. Histopathologic analyses of 21 available specimens revealed 19 pure schwannomas. In two cases (10 %) hybrid features of both schwannoma and neurofibroma were identified, with mast cells within regions consistent with neurofibroma. CONCLUSIONS: PNSTs can be resected safely in NF2, even if they involve major peripheral nerves. A small proportion (10 %) of these tumors harbor hybrid histologic features, which may explain reports of plexiform or multi-fascicular tumors in NF2.

Neuroma of the Infrapatellar branch of the saphenous nerve following Total knee Arthroplasty: a case report.

BACKGROUND: Injury to the infrapatellar branch of the saphenous nerve (IBSN) is common during total knee arthroplasty (TKA) with a standard midline skin incision. Occasionally, painful neuromas form at the transection of nerve and cause pain and limitation of the range of motion of the knee joint. CASE PRESENTATION: A 70-year-old woman experienced right knee pain and stiffness for 4 years after TKA. Physical assessment revealed medial tenderness; Tinel's sign was positive. Radiographs revealed that the prosthesis was well-placed and well-fixed. She was diagnosed with arthrofibrosis and possible neuroma after TKA. She underwent right knee exploration, neurectomy, adhesiolysis and spacer exchange. The neuroma-like tissue was sent for pathological examination. The patient recovered uneventfully and at 3-month follow-up reported no recurrence of pain or stiffness. The pathological report confirmed the diagnosis of neuroma. CONCLUSIONS: IBSN injury should be a concern if surgeons encounter a patient who has pain and stiffness after TKA. Tinel's sign, local anesthetic injection, MRI and ultrasound could help the diagnosis and identify the precise location of neuroma. Surgical intervention should be performed if necessary.

Surgical treatment of giant benign sacral neurogenic tumors using the posterior-only approach.

OBJECTIVE: Few studies have reported on the effects of surgery on giant benign sacral neurogenic tumors since these tumors represent a major challenge for surgical oncologists. In the present study, we retrospectively reviewed our experiences in performing resections of giant benign sacral neurogenic tumors using the posterior-only approach via "fishing" method, and assessed the outcomes of patients after this procedure. PATIENTS AND METHODS: We retrospectively reviewed and analyzed the records of 155 consecutive patients with giant benign sacral neurogenic tumors who underwent resection by a posterior-only approach in our center from Feb 2008 to Feb 2018. RESULTS: Operations lasted for a mean of 183 ±â€¯37 min (range, 125-230 min). The mean estimated blood loss during the surgery was 1098 ±â€¯889 ml (range, 600-4100 ml). The mean follow-up time was 65 ±â€¯39 months (range, 12-118 months). By the last follow-up, the local recurrence rate was 7.1% (11/155), the combined overall symptom resolution and remission rate was 91.1% (123/135), and the total complication rate was 17.4% (27/155). CONCLUSION: The posterior-only approach is safe and effective in patients with giant benign sacral neurogenic tumors.

High-resolution ultrasonography and shear-wave sonoelastography of a cystic radial nerve Schwannoma.

Peripheral nerve tumors are often evaluated with magnetic resonance imaging (MRI), although there are many advantages offered with high-resolution ultrasonography (HRUS). This case report emphasizes the value of HRUS in the diagnosis and management of a patient with a cystic radial nerve Schwannoma. In addition, information on tumor stiffness, obtained with shear-wave sonoelastography (SWE), is presented.

Comparison of Different Sequences of Magnetic Resonance Imaging and Ultrasonography with Nerve Conduction Studies in Peripheral Neuropathies.

BACKGROUND: Peripheral neuropathies refer to a group of disorders in which there is damage to the nerves of the peripheral nervous system. Electrophysiologic studies are the main stay for the diagnosis of peripheral neuropathies. However, direct visualization of the nerves is possible with exact localization of site of disease with high-resolution ultrasonography (USG) and 3-Tesla magnetic resonance imaging (MRI) scanner, and newer magnetic resonance (MR) sequences. METHODS: We performed a cross-sectional study including 55 patients and 64 nerves with upper limb peripheral neuropathies. All patients included underwent high-resolution focused USG of the nerves and MR neurography. A nerve conduction velocity study was performed for reference. RESULTS: The diagnostic confidence of the turbo spin echo T2-weighted (T2W) MR sequence was seen to be highest, with a sensitivity of 95.31%, whereas it was 81.25% for USG. Continuity of the nerve in patients with traumatic neuropathy was seen in 65.7% and 62.86% (22/35) nerves on MRI and USG, respectively. T1-weighted and T2W MR sequences were seen to be equally effective in establishing the continuity of the nerve. Increase in the caliber/thickening was seen in 77% of cases on MRI and 73.8% of cases on USG. Neuroma formation was seen equally on both MR and USG in 60.66%. We consistently found low fractional anisotropy (FA) values at the site of disease. CONCLUSIONS: USG is a sensitive technique to diagnose peripheral neuropathies and it should be used as a screening modality for focused MR to be performed later. Turbo spin echo T2W fast spin has the highest sensitivity to identify nerve disease and is comparable with nerve conduction studies. Among the newer sequences, diffusion tensor imaging should be performed to increase diagnostic confidence.

Extrarenal rhabdoid tumor presented with an immobile arm in a one-year-old boy.

Infants with an immobile arm may be easily overlooked in primary care settings. Differential diagnoses include injuries, infections, neuropathies, ischemia and rarely, neoplasms. We report the case of a one-year-old boy with weakness in his left arm after minor trauma with a diagnosis of brachial plexus palsy initially. After rehabilitation for 2months, his weakness progressed to unsteady gait and quadriparesis. MRI revealed a huge solid tumor in the left supraclavicular fossa, which also involved the left brachial plexus, upper thoracic cavity, and left paravertebral space with invasion into the spinal canal. Microscopically, the medium-large polygonal tumor cells had an eccentric eosinophilic cytoplasm and immunostaining showed a loss of nuclear INI1 expression. Array comparative genomic hybridization of the tumor tissue confirmed a segmental deletion at chromosome region 22q11.23 involving the SMARCB1 gene. The final diagnosis was cervical paravertebral malignant rhabdoid tumor with intraspinal epidural and intradural invasion, a rare case of extrarenal extracranial rhabdoid tumor (ERRT). The intraspinal part of the tumor was resected followed by interval-compressed chemotherapy with vincristine-doxorubicin-cyclophosphamide alternating with ifosfamide-etoposide (VDC/IE). The tumor showed very good partial response to four cycles of chemotherapy with gradual recovery of neurological symptoms. ERRT is a very rare and aggressive tumor that mainly occurs in infants and children and may manifest with vague neurological symptoms when it involves the spinal cord and/or peripheral nerves. A neoplasm such as ERRT originating from or involving the brachial plexus should be considered in the differential diagnosis of an immobile arm in infancy.

Multiple Neuromas Cause Painful "Jumping Stump" in a Transfemoral Amputee: A Case Report.

Painful "jumping stump" is an uncommon but very disturbing complication postamputation. This condition is one of the movement disorder entities resulting from peripheral nerve pathology, often known as "peripherally induced movement disorders." Previously case reports have been written about painful and nonpainful incidence of "jumping stump"; however, only the earliest "jumping stump" article in 1852 suspected that neuromas might influence the involuntary movement. In this study, we describe a 38-year-old man with bilateral transfemoral amputee who suffered from painful "jumping stump" with multiple neuromas confirmed by imaging. He was treated successfully by ultrasound-guided phenol injection into the sciatic neuroma stalks. The pathophysiology of jumping stump and its possible association with neuroma are briefly discussed.

Transischiorectal fossa approach for resection of pudendal nerve schwannoma: case report.

Pudendal nerve schwannomas are very rare, with only two cases reported in the English-language literature. The surgical approaches described in these two case reports are the transgluteal approach and the laparoscopic approach. The authors present the case of a patient with progressive pelvic pain radiating ipsilaterally into her groin, vagina, and rectum, who was subsequently found to have a pudendal schwannoma. The authors used a transischiorectal fossa approach and intraoperative electrophysiological monitoring and successfully excised the tumor. This approach has the advantage of direct access to Alcock's canal with minimal disruption of the pelvic muscles and ligaments. The patient experienced complete relief of her pelvic pain after the procedure.

Post-traumatic neuroma due to closed nerve injury. Is recovery after peripheral nerve trauma related to ultrasonographic neuroma size?

OBJECTIVE: traumatic neuroma is a pathological condition of peripheral nervous system consisting of localized proliferation of injured nerve elements. The symptoms depend on the type of involved nerve (motor and/or sensitive) and on the site and the extension of the lesion. Ultrasound is the best tool to depict the morphology of nerve, especially in traumatic conditions. We present a study aimed to assess the correlation between the degree of nerve function and the ultrasound morphology of neuromas. PATIENTS AND METHODS: we retrospectively evaluated 18 patients with neuromas (not transected) occurred after a closed nerve trauma evaluated with clinical and ultrasound assessment. The clinical evaluation was related to the % of increase of cross sectional area as detected by nerve ultrasound respect to normal nerve. RESULTS: we observed that dimensions of neuromas are not related to function until neuroma have cross sectional area 5 times enlarged respect to normal nerve, in this case recovery never occurs. CONCLUSION: our study failed to clear detect a relation between cross sectional area enlargement of neuroma and nerve function, but showed a cut off beyond which prognosis is negative. This result provide some useful information for prognosis, nevertheless we believe that future perspective studies are needed to better understand the timing of developing neuromas and its evolution.

Neurolymphomatosis: A report of 2 cases representing opposite ends of the clinical spectrum.

INTRODUCTION: Neurolymphomatosis (NL) is a rare disorder characterized by invasion of cranial or peripheral nerves, nerve roots, or plexi, usually by aggressive subtypes of non-Hodgkin lymphoma (NHL). The most common clinical presentation is that of a painful polyneuropathy or polyradiculopathy, followed by cranial neuropathy and, less frequently, by painless polyneuropathy. METHODS: Clinical and pathologic findings are reported for 2 NL cases. RESULTS: The following 2 patients with NL, with disparate clinical presentations, are presented: a patient with subacute onset, painful, multifocal, mixed axonal and demyelinating radiculoplexus neuropathy due to a large B-cell NHL, who required 2 targeted fascicular nerve biopsies to demonstrate NL; and a patient with a slowly progressive, length-dependent axonal polyneuropathy due to a low-grade B-cell lymphoproliferative disorder, as shown on a diagnostic sural nerve biopsy. CONCLUSIONS: The cases described illustrate the wide clinical spectrum of NL.

High-resolution ultrasonography and diffusion tensor tractography map normal nerve fascicles in relation to schwannoma tissue prior to resection.

The goals of the present study were to demonstrate the ability of high-resolution ultrasonography to delineate normal nerve fascicles within or around peripheral nerve sheath tumors (NSTs). A blinded examiner evaluated 2 patients with symptomatic upper limb NSTs with high-resolution ultrasonography performed in the perioperative suite using a portable ultrasonography system. Ultrasonographic examinations located the tumor mass and identified the normal nerve fascicles associated with the mass. The locations of normal nerve tissue were mapped and correlated with results of MR tractography, operative inspection, and intraoperative electrophysiological monitoring. The study demonstrated a close correlation between normal nerve fascicles identified by ultrasonography, MR tractography, and intraoperative electrophysiological mapping. In particular, ultrasonographic examinations accurately identified the surface regions of the tumor without overlying normal nerve tissue. These preliminary data suggest that preoperative ultrasonographic examinations may provide valuable information, supplementary to the information obtained from intraoperative electrophysiological monitoring. Identification of normal nerve tissue prior to surgery may provide additional information regarding the risk of iatrogenic nerve injury during percutaneous tumor biopsy or open resection of the tumor and may also aid in selecting the optimum surgical approach.

Multiple schwannomas of the ulnar nerve.

Schwannoma is a relatively uncommon benign tumour of the soft tissues. We present a rare case of 10 tumours localised to the ulnar nerve.

Intraneural perineurioma of unilateral radial and median nerves manifesting with long-standing focal amyotrophy in a 14-year-old-boy.

Intraneural perineuriomas are rare tumors of the peripheral nerves with unique immunohistochemical findings. In this report, we highlight the clinical and imaging findings of an adolescent male with histologically proven intraneural perineurioma involving multiple nerves. The salient features included a clinically progressive course, imaging evidence of involvement of long segments of multiple nerves, enlargement of individual fascicles within the affected nerves, and intense contrast enhancement of the enlarged fascicles. The identification of enlarged fascicles with intense contrast enhancement within the affected and distended nerve segments may aid in distinguishing intraneural perineurioma from other tumors affecting the peripheral nerves.