Nicholas D. Coppa, H. Jeffrey Kim and Kevin M. McGrail
✓ The spontaneous resolution of syringomyelia in the setting of a Chiari malformation Type I (CM-I) has been reported infrequently. Several theories about the pathogenesis and spontaneous resolution of syringomyelia associated with CM-I have been proposed. The authors present the case of a patient with spontaneous resolution of a CM-I and syringomyelia coinciding with the development of cerebrospinal fluid (CSF) otorrhea. Although cases of spontaneous resolution of syringomyelia have been reported, this is the first reported case of spontaneous resolution of syringomyelia and a CM-I associated with the simultaneous development of CSF otorrhea.
Louis J. Kim, Volker K. H. Sonntag, Jonathan T. Hott, Jeffrey A. Nemeth, Jeffrey D. Klopfenstein and Lisa Tweardy
Russell R. Lonser, Martin Baggenstos, H. Jeffrey Kim, John A. Butman and Alexander O. Vortmeyer
Although endolymphatic sac tumors (ELSTs) frequently destroy the posterior petrous bone and cause hearing loss, the anatomical origin of these neoplasms is unknown. To determine the precise topographic origin of ELSTs, the authors analyzed the imaging, operative, and pathological findings in patients with von Hippel–Lindau disease (VHL) and ELSTs.
Consecutive VHL patients with small (≤ 1.5 cm) ELSTs who underwent resection at the National Institutes of Health were included. Clinical, imaging, operative, and pathological findings were analyzed.
Ten consecutive VHL patients (6 male and 4 female) with 10 small ELSTs (≤ 1.5 cm; 9 left, 1 right) were included. Serial imaging captured the development of 6 ELSTs and revealed that they originated within the intraosseous (vestibular aqueduct) portion of the endolymphatic duct/sac system. Imaging just before surgery demonstrated that the epicenters of 9 ELSTs (1 ELST was not visible on preoperative imaging) were in the vestibular aqueduct. Inspection during surgery established that all 10 ELSTs were limited to the intraosseous endolymphatic duct/sac and the immediately surrounding region. Histological analysis confirmed tumor within the intraosseous portion (vestibular aqueduct) of the endolymphatic duct/sac in all 10 patients.
ELSTs originate from endolymphatic epithelium within the vestibular aqueduct. High-resolution imaging through the region of the vestibular aqueduct is essential for diagnosis. Surgical exploration of the endolymphatic duct and sac is required for complete resection.
John A. Butman, Edjah Nduom, H. Jeffrey Kim and Russell R. Lonser
To determine if physiologically based MRI sequences can be used to detect endolymphatic sac tumor (ELST)–associated hydrops, the authors performed contrast-enhanced delayed FLAIR imaging in consecutive ELST patients with clinical findings consistent with hydrops.
Consecutive patients with von Hippel-Lindau (VHL) disease and clinical findings of endolymphatic hydrops and ELSTs underwent contrast-enhanced delayed FLAIR MRI. Clinical, audiological, operative, and imaging findings were analyzed.
Three patients (2 male, 1 female) with 4 ELSTs (1 patient had bilateral ELSTs) were identified who had clinical findings consistent with endolymphatic hydrops. Computed tomography and MRI evidence of an ELST was found in all patients. Their mean age at initial evaluation was 39.7 years (range 28–51 years). All patients demonstrated progressive sensorineural hearing loss that was associated with episodic vertigo and tinnitus. Contrast-enhanced delayed FLAIR MRI clearly demonstrated dilation of the membranous labyrinth consistent with hydrops in the affected ears but not the unaffected ears. Two patients underwent resection of the associated ELST that resulted in stabilization of progressive hearing loss, as well as amelioration of tinnitus and vertigo.
Contrast-enhanced delayed FLAIR MRI can be used to detect ELST-associated hydrops. Noninvasive MRI detection of hydrops can permit earlier detection of ELSTs in patients with VHL disease and provides direct insight into a mechanism that underlies ELST-associated audiovestibular morbidity.
Louis J. Kim, Harold L. Rekate, Jeffrey D. Klopfenstein and Volker K. H. Sonntag
Object. The reduction of basilar invagination associated with Chiari I malformations in pediatric patients is often possible. Eleven children ranging in age from 1.5 to 17 years underwent a novel treatment method involving decompression, manual reduction, and posterior instrumentation-augmented fusion. Outcomes were evaluated retrospectively.
Methods. After decompression of the lesion, manual craniocervical distraction and extension were performed, followed by posterior occipitocervical fusion involving rigid internal fixation. All patients were symptomatic at presentation. Intraoperative monitoring included somatosensory evoked potentials, fluoroscopy, and direct intradural demonstration of the craniocervical junction. No new neurological deficits occurred immediately after surgery. Perioperatively, symptoms in seven patients improved significantly and in four they remained unchanged. Three patients required subsequent transoral resections. During long-term follow up (mean 39.4 months, range 3–92 months) symptoms improved markedly in nine, remained unchanged in one, and progressively worsened in one patient.
Conclusions. In selected cases, manual cervical distraction and extension, posterior fixation, and fusion appear to provide a safe, effective standalone treatment for basilar invagination associated with Chiari malformation in children.
Jay Jagannathan, John A. Butman, Russell R. Lonser, Alexander O. Vortmeyer, Christopher K. Zalewski, Carmen Brewer, Edward H. Oldfield and H. Jeffrey Kim
✓ Endolymphatic sac tumors (ELSTs) are locally invasive neoplasms that arise in the posterior petrous bone and are associated with von Hippel–Lindau (VHL) disease. These tumors cause symptoms even when microscopic in size (below the threshold for detectability on imaging studies) and can lead to symptoms such as hearing loss, tinnitus, vertigo, and facial nerve dysfunction. While the mechanisms of audiovestibular dysfunction in patients harboring ELSTs are incompletely understood, they have critical implications for management. The authors present the case of a 33-year-old man with VHL disease and a 10-year history of progressive tinnitus, vertigo, and left-sided hearing loss. Serial T1-weighted magnetic resonance (MR) imaging and computed tomography scans revealed no evidence of tumor, but fluid attenuated inversion recovery (FLAIR) MR imaging sequences obtained after hearing loss demonstrated evidence of left intralabyrinthine hemorrhage. On the basis of progressive disabling audiovestibular dysfunction (tinnitus and vertigo), FLAIR imaging findings, and VHL disease status, the patient underwent surgical exploration of the posterior petrous region, and a small (2-mm) ELST was identified and completely resected. Postoperatively, the patient had improvement of the tinnitus and vertigo. Intralabyrinthine hemorrhage may be an early and the only neuroimaging sign of an ELST in patients with VHL disease and audiovestibular dysfunction. These findings support tumor-associated hemorrhage as a mechanism underlying the audiovestibular dysfunction associated with ELSTs.
Nitrogen mustard, vincristine, procarbazine, and prednisone as adjuvant chemotherapy in the treatment of medulloblastoma
A Pediatric Oncology Group study
Jeffrey P. Krischer, Abdelsalem H. Ragab, Larry Kun, Tae H. Kim, John P. Laurent, James M. Boyett, Cornelius J. Cornell, Michael Link, Annette Ridolfi Luthy and Bruce Camitta
✓ In a randomized postoperative trial, adjuvant post-irradiation chemotherapy, consisting of nitrogen mustard, vincristine, procarbazine, and prednisone (MOPP), was tested versus radiation therapy alone for newly diagnosed medulloblastoma in patients between 1 and 21 years of age. Patients treated with irradiation plus MOPP had a statistically significant increase in overall survival rate at 5 years posttreatment compared to patients treated with radiation therapy alone (74% vs. 56%; p = 0.06, adjusted for race and gender). Although the overall study failed to show a statistically significant advantage for irradiation plus MOPP in event-free survival (p = 0.18), statistical significance was attained in children 5 years of age or older (p = 0.05). More severe hematological toxicities occurred in the group with irradiation plus MOPP; however, this hematotoxicity appeared to be tolerable and acceptable. These results suggest that patients may benefit from combined irradiation and chemotherapy following surgery for medulloblastoma.
Timothy W. A. Vogel, Alexander O. Vortmeyer, Irina A. Lubensky, Youn-Soo Lee, Makoto Furuta, Barbara Ikejiri, H. Jeffrey Kim, Russell R. Lonser, Edward H. Oldfield and Zhengping Zhuang
Object. Von Hippel—Lindau (VHL) disease is characterized by multiple tumors in specific organs. The cell of origin and the reason for the particular organ distribution of the tumors remains unknown. Endolymphatic sac tumor (ELST) is one of the lesions associated with VHL disease. Data from previous studies of VHL disease—associated hemangioblastomas (HBs) and renal cell carcinomas (RCCs) have indicated that VHL gene deficiency causes coexpression of erythropoietin (Epo) and its receptor (Epo-R), which facilitates tumor growth.
Methods. The authors studied ELSTs from five patients with VHL germline mutations. Analysis of the five ELST samples revealed loss of the wild-type allele, consistent with Knudson's two-hit hypothesis for tumorigenesis. All five ELST specimens were characterized microscopically and by immunohistochemical analysis. Coexpression of Epo and Epo-R was found in all five tumors on immunohistochemical studies and confirmed through reverse transcription—polymerase chain reaction and Western blot analysis.
Conclusions. Expression of Epo appears to be a result of VHL gene deficiency, whereas the simultaneous coexpression of Epo-R may reflect a developmental mechanism of tumorigenesis. Coexpression of Epo and Epo-R in ELSTs together with the morphological and genetic similarities of these lesions with other VHL disease—associated tumors indicates that VHL disease—associated tumors in different organs share common pathogenetic pathways.
H. Jeffrey Kim, John A. Butman, Carmen Brewer, Christopher Zalewski, Alexander O. Vortmeyer, Gladys Glenn, Edward H. Oldfield and Russell R. Lonser
Object. Endolymphatic sac tumors (ELSTs), which often are associated with von Hippel—Lindau (VHL) disease, cause irreversible hearing loss and vestibulopathy. Clinical and imaging surveillance protocols provide new insights into the natural history, mechanisms of symptom formation, and indications for the treatment of ELSTs. To clarify the uncertainties associated with the pathophysiology and treatment of ELSTs, the authors describe a series of patients with VHL disease in whom serial examinations recorded the development of ELSTs.
Methods. Patients with VHL disease were included if serial clinical and imaging studies captured the development of ELSTs, and the patients underwent tumor resection. The patients' clinical, audiological, and imaging characteristics as well as their operative results were analyzed.
Five consecutive patients (three men and two women) with a mean age at surgery of 34.8 years and a follow-up period of 6 to 18 months were included in this study. Audiovestibular symptoms were present in three patients before a tumor was evident on neuroimaging. Imaging evidence of an intralabyrinthine hemorrhage coincided with a loss of hearing in three patients. Successful resection of the ELSTs was accomplished by performing a retrolabyrinthine posterior petrosectomy (RLPP). Hearing stabilized and vestibular symptoms resolved after surgery in all patients. No patient has experienced a recurrence.
Conclusions. Audiovestibular symptoms, including hearing loss, in patients with VHL disease can be the result of microscopic ELSTs. Once an ELST has been detected, it can be completely resected via an RLPP with preservation of hearing and amelioration of vestibular symptoms. Early detection and surgical treatment of small ELSTs, when hearing is still present, should reduce the incidence and severity of hearing loss, tinnitus, vertigo, and cranial nerve dysfunction, which are associated with these tumors.