William R. Schmitt

Auditory and vestibular symptoms and chronic subjective dizziness in patients with Ménière's disease, vestibular migraine, and Ménière's disease with concomitant vestibular migraine

Objective To compare presentations of Ménière’s disease (MD), vestibular migraine (VM), and Ménière’s disease plus vestibular migraine (MDVM), with and without comorbid chronic subjective dizziness (CSD). Study Design Retrospective review with diagnosis confirmed by consensus conference of investigators using published criteria for MD, VM, and CSD. Setting Ambulatory, tertiary dizziness clinic. Patients Approximately 147 consecutive patients with diagnoses of MD, VM, or MDVM, with/without comorbid CSD. Interventions Diagnostic consultation. Main Outcome Measures Similarities and differences between diagnostic groups in demographics; symptoms; and results of neurotologic, audiometric, and vestibular laboratory assessments. Results Seventy-six patients had MD, 55 MD alone. Ninety-two patients had VM, 71 VM alone. Twenty-one patients had MDVM, representing about one-quarter of those diagnosed with MD or VM. Clinical features thought to differentiate VM from MD were found in all groups. Twenty-seven patients with VM (38%) had ear complaints (subjective hearing loss, aural pressure, and tinnitus) during episodes of vestibular symptoms and headache, including 10 (37%) with unilateral symptoms. Conversely, 27 patients with MD alone (49%) had headaches with migraine features that did not meet full IHS diagnostic criteria, migrainous symptoms (photophobia, headache with vomiting), or first-degree relative with migraine. Including MDVM patients, 59% (45/76) of all patients with MD had migrainous features. Thirty-two patients had CSD; most (29; 91%) were in the VM group. Conclusion Comorbidity was common between MD and VM, and their symptoms overlapped. More specific diagnostic criteria are needed to differentiate these diseases and address their coexistence. CSD co-occurred with VM but was rarely seen with MD.

Radiation-induced sarcoma in a large vestibular schwannoma following stereotactic radiosurgery: case report.

BACKGROUND AND IMPORTANCE:Stereotactic radiosurgery (SRS) has been employed with increasing frequency in the treatment of benign intracranial tumors. While the risk for radiation-induced malignancy has been well studied for fractionated external beam radiation, reports of SRS-associated malignancy have only begun to emerge over the past 10 years. CLINICAL PRESENTATION:We present a case of a rapidly enlarging, presumed sporadic vestibular schwannoma in a 51-year-old man treated with SRS. Serial imaging over the next 7.5 years demonstrated good radiographic response with consistent involution of the tumor. The patient then developed rapid neurologic deterioration and sustained tumor growth on follow-up imaging. The tumor was resected via a translabyrinthine approach, and pathologic analysis demonstrated undifferentiated high-grade pleomorphic sarcoma (UHGPS). CONCLUSION:This is the first report of undifferentiated high-grade pleomorphic sarcoma (formerly called malignant fibrous histiocytoma) following SRS. This case demonstrates the difficulty of establishing malignant degeneration of a neoplasm following SRS without pretreatment tissue diagnosis. Patients with presumed benign tumors should be counseled about the rare risk of malignant transformation prior to undertaking SRS.

Pediatric cerebellopontine angle and internal auditory canal tumors

OBJECT The aim in this study was to describe the clinical presentation, differential diagnosis, and risk for neurofibromatosis Type 2 (NF2) in pediatric patients presenting with cerebellopontine angle (CPA) and internal auditory canal (IAC) tumors. METHODS The authors conducted a retrospective study at a tertiary care academic referral center. All patients with an age ≤ 18 years who had presented with an extraaxial CPA or IAC tumor between 1987 and 2012 were included in the study cohort. Data regarding symptoms, diagnosis, tumor characteristics, and NF2 status were collected and analyzed. RESULTS Sixty patients (55% female, 45% male) harboring 87 tumors were identified. The mean age at diagnosis was 12.8 years (median 14.0 years, range 0.9-18.9 years). Schwannomas were the most commonly identified lesions (57 of 87 tumors, including 52 vestibular, 3 facial, and 2 trigeminal schwannomas), followed by meningiomas (5 of 87) and epidermoid cysts (4 of 87). Six malignant tumors were diagnosed, including small-cell sarcoma, squamous cell carcinoma, malignant meningioma, atypical rhabdoid-teratoid tumor, endolymphatic sac tumor, and malignant ganglioglioma. Headache, followed by hearing loss and imbalance, was the most common presenting symptom, whereas dysphagia, otalgia, and facial pain were uncommon. Neurofibromatosis Type 2 was diagnosed in 20 (61%) of 33 patients with vestibular schwannoma (VS), while the other 13 patients (39%) had sporadic tumors. Nineteen of the 20 patients with NF2 met the diagnostic criteria for that disorder on initial presentation, and 15 of them presented with bilateral VS. At the last follow-up, 19 of the 20 patients subsequently diagnosed with NF2 demonstrated bilateral VSs, whereas 1 patient with a unilateral VS and multiple other NF2-associated tumors has yet to demonstrate a contralateral VS to date. Only 1 patient presenting with an isolated unilateral VS and no family history of NF2 demonstrated a contralateral VS on subsequent radiological screening. CONCLUSIONS Cerebellopontine angle and IAC tumors in the pediatric population are rare. There are several noteworthy differences between the adult and pediatric populations harboring these lesions. While VS is the most common pathology in both age groups, the lesion was found in only 60% of the pediatric patients in the present study. Unlike in adults, VSs in the pediatric population were associated with NF2 in over one-half of all cases. The majority of pediatric patients with NF2 fulfilled the diagnostic criteria at initial presentation; however, approximately 7% of patients presenting with a seemingly sporadic (no family history of NF2) unilateral VS will meet the criteria for NF2 later in life. Finally, malignancies account for a significantly higher percentage (10%) of cases among pediatric patients. These findings underscore the importance of early screening and close radiological follow-up and may be helpful in patient counseling.

Closure of Scalp and Forehead Defects Using External Tissue Expander

OBJECTIVE To describe the novel use of an external tissue expander in the reconstruction of scalp and forehead defects. METHODS A prospective review was performed on 7 patients who underwent extirpation of head and neck malignant neoplasms resulting in scalp and forehead defects. Reconstruction was performed using an external tissue expander device. Patient clinical factors, defect size, and photographs were collected. RESULTS Seven patients had large scalp and forehead defects ranging in greatest dimension from 5.0 ×4.0 to 8.0 ×7.0 cm. The external tissue expander was in place for 6 to 14 days, reducing the defect sizes by 50% to 99%. At the time of device removal, primary closure was achieved in 5 patients. One patient required bilateral advancement rotation flaps, and 1 patient healed by second intention. One patient with a history of scalp irradiation and diabetes had partial skin loss after device removal and required reconstruction with a latissimus dorsi myocutaneous free flap. There were no other postoperative complications, wound breakdown, or device failures. CONCLUSION External tissue expansion is a safe and effective technique for closing large scalp and forehead defects that would otherwise require skin grafting or free flap reconstruction.

The anatomically intact but electrically unresponsive facial nerve in vestibular schwannoma surgery.

BACKGROUND Permanent facial nerve (FN) paresis after vestibular schwannoma surgery is distressing to both the patient and surgeon. Intraoperative electrophysiological testing has proven invaluable in reducing the incidence of FN injury and may assist in prognosticating long-term function. OBJECTIVE To report definitive FN outcomes among a cohort of patients with an unevokable but anatomically intact seventh nerve after microsurgical vestibular schwannoma resection. METHODS All patients undergoing vestibular schwannoma surgery between 2000 and 2010 at a single tertiary academic referral center were identified. Intraoperative FN monitoring data and definitive FN outcomes were reviewed, and all patients with an anatomically intact but electrically unresponsive FN were included. RESULTS Eleven patients met the inclusion criteria. The median preoperative and definitive postoperative FN scores were House-Brackmann grades 1 and 3, respectively. The median time to definitive FN recovery was 9.4 months. CONCLUSION These data demonstrate that even among this extreme subset, modern electroprognostic testing strategies are incapable of reliably predicting poor outcomes. Therefore, if FN continuity is maintained, attempts at same-surgery FN repair should not be pursued.

Nodular enhancement within the internal auditory canal following retrosigmoid vestibular schwannoma resection: a unique radiological pattern

OBJECT The authors describe the unique occurrence of nodular enhancement within the fundus of the internal auditory canal (IAC) lateral to the preoperative radiological tumor margin following gross-total vestibular schwannoma (VS) resection. METHODS The nature of the study was a retrospective chart review of records. The authors reviewed the cases of all patients who underwent microsurgical resection of a VS between January 2000 and January 2010 at a single tertiary referral center. Patients with incomplete resection, neurofibromatosis Type 2, and those with fewer than 2 postoperative MR images available for review were excluded. Postsurgical patients with IAC enhancement located lateral to the preoperative imaging-delineated tumor margin were identified. Lesion morphology was characterized on serial MR imaging studies. Clinical follow-up and outcomes were recorded. RESULTS Over the past decade, 350 patients underwent microsurgical VS resection. Of these, 16 patients met study criteria and were found to have postsurgical enhancement in the distal aspect of the IAC lateral to the imaging limits of the preoperative tumor margin on the first postoperative MR imaging study (37.5% women, median age 45 years). Initial MR imaging was performed at a mean of 3.1 months following surgery, and the mean radiological follow-up duration was 39.8 months (range 16.4-101.9 months). None of the 16 patients developed recurrence during the follow-up course. CONCLUSIONS In contrast to previous publications that have reported a high rate of recurrence in cases involving nodular enhancement within the original tumor bed, postoperative enhancement in the IAC lateral to the original tumor margin appears to carry much less risk for tumor recurrence. These findings may be helpful when counseling patients on the recommended frequency of postoperative follow-up imaging.

Inhibition of MEK pathway in vestibular schwannoma cell culture

The purpose of this study was to evaluate the Ras GTPase (Ras) to extracellular signal‐regulated kinase (ERK) pathway in vestibular schwannoma (VS) cell cultures and patient excised schwannoma tumors. Mitogen‐activated protein kinase kinase (MEK) inhibitor CI‐1040 (PD184352) was utilized to evaluate the effect of specific MEK inhibition on benign schwannoma cell culture proliferation and apoptosis.