Faculty Bibliography

OBJECTIVES/OBJECTIVE:This study was conducted to evaluate magnetic resonance imaging (MRI) as an objective measure of survival of micronized acellular human dermal graft (Cymetra, LifeCell Corporation) injected into the thyroarytenoid muscle for augmentation of unilateral vocal fold paralysis. METHODS:We performed a retrospective review of MRI scans obtained in 6 patients in whom Cymetra was injected into the thyroarytenoid muscle. Gadolinium-enhanced MRI of the larynx was performed 3 days, 1 month, 8 months, 11 months, 15 months, and 21 months after injection. The survival of injected Cymetra was assessed according to information obtained from the MRI scan. Images were also obtained for 1 cm3 of reconstituted Cymetra paste. RESULTS:The identification of Cymetra in the larynx is based on its proteinaceous content. T1-weighted images of the injected material in the true vocal fold showed hyperintense foci corresponding to injected Cymetra. Hyperintense signal was also present on the T2-weighted images. Persistence of the injected Cymetra was readily detectable by MRI for as long as 11 months. CONCLUSIONS:Cymetra is a viable treatment option for vocal fold augmentation. The duration of survival of Cymetra (as long as 11 months) makes it a good option in cases in which longer survival of the injectable material is needed.

BACKGROUND AND PURPOSE: The petrous and cavernous segments of the extradural internal carotid artery take a complex course through the skull base before entering the subarachnoid space distal to the cavernous sinus. Despite the protection from trauma afforded by the anatomy, the petrous and carotid internal carotid artery (ICA) segments of the vessel remains subject to disease, the most important of which are aneurysms. Aneurysms affecting the petrous portion of the vessel are extremely uncommon, and presentation with otologic symptoms is unusual. These symptoms include hearing loss, tinnitus, and life threatening hemorrhage. This article emphasizes the need for a high level of suspicion for aneurysm as a potential cause for otologic symptoms. We report and discuss three cases of petrous carotid aneurysms with otologic manifestations to increase the awareness and aid in the diagnosis and treatment of this uncommon disorder. METHODS: The medical records and imaging studies of three patients presenting to our institution with aneurysms involving the petrous internal carotid artery were reviewed. One presented with progressive bilateral sensorineural hearing loss. The next patient presented with pulsatile tinnitus. The last patient presented to the emergency room unresponsive with severe epistaxis. RESULTS: All three patients had imaging studies revealing petrous carotid aneurysms. Each patient had symptoms related to the aneurysms ranging from hearing loss, tinnitus, and life-threatening hemorrhage. CONCLUSION: Petrous carotid aneurysms are rare, and presentation with otologic symptoms is unusual. Awareness of these lesions as a cause of otologic symptoms, however, is highly important. These cases also illustrate the usefulness of endovascular treatments for aneurysms of the petrous portion of the internal carotid artery, which are extremely difficult to treat by using an open surgical approach.

BACKGROUND: Capillary hemangiomas are benign vascular lesions that commonly present at birth or in early infancy on the face, scalp, back, or chest. The authors present an exceedingly rare case of an intracranial capillary hemangioma arising in an adult. Only 4 biopsy-proven cases have been reported in the pediatric population previous to this case report. CASE DESCRIPTION: A 31-year-old pregnant woman presented at 38 weeks of gestation with severe headaches, nausea, and vomiting. Imaging revealed an extra-axial mass lesion arising from the tentorium with both supra- and infratentorial components. The patient underwent a resection of her tumor, which was diagnosed as a capillary hemangioma by histopathologic examination. The patient required 2 further resections after the lesion exhibited a rapid regrowth from residual tumor in the left transverse sinus. The patient has remained free of disease 41 months out from her third surgery. CONCLUSIONS: Intracranial capillary hemangiomas are exceedingly rare entities, with a capability for rapid growth. When gross total resection cannot be achieved, these patients should be observed closely, and the use of adjuvant radiotherapy should be considered

Lhermitte-Duclos disease is a rare benign lesion of uncertain pathogenesis characterized by distortion of the normal cerebellar laminar cytoarchitecture. There is a characteristic MR imaging appearance of a nonenhancing mass in the cerebellar hemisphere with a striated pattern. We report two cases of Lhermitte-Duclos disease and describe findings on diffusion-weighted MR imaging.

In this work, the feasibility of using T2rho weighting as an MR contrast mechanism is evaluated. Axial images of a human brain were acquired using a single-slice spin-lock T2rho-weighted pulse sequence and compared to analogous T2-weighted images of the same slice. The contrast between white matter and gray matter in T2rho-weighted images was approximately 40% greater than that from T2-weighted data. These preliminary data suggest that the novel contrast mechanism of T2rho can be used to yield high-contrast T2-like images.

The widespread acceptance of functional endoscopic sinus surgery (FESS) underscores the importance of understanding the relevant anatomy of the paranasal sinuses as a means of providing a roadmap to the otorhinolaryngologist prior to surgery. The radiologist can address important imaging issues for the ear, nose, and throat (ENT) surgeon before FESS is undertaken. There are two main questions that the radiologist should address: 1. Are there anatomic features on the computed tomography (CT) scan that predispose the patient to impaired mucociliary clearance? 2. Are there anatomic features that pose a surgical hazard?

We present a case of an 85-year-old woman with a 40-year history of progressive bilateral sensorineural hearing loss. Imaging studies demonstrated bilateral pseudoaneurysms of the petrous portion of the internal carotid arteries eroding into both cochleas. To our knowledge, this is the first case report of such lesions.

STUDY DESIGN: A case of intradural venous varix producing a mass-like lesion in the lumbar spine is reported. OBJECTIVE: To present a rare cause of an intradural mass lesion along the cauda equina. To present radiologic findings of this entity and to offer a hypothesis for its formation. SUMMARY OF BACKGROUND DATA: Epidural venous varices have been described previously in the literature. To the authors' knowledge, no cases of intradural venous varix presenting as an intradural mass have been reported previously. MATERIALS AND METHODS: An elongated, serpentine intradural mass was discovered on routine lumbar MRI performed for investigation of the patient's radiculopathy. The patient underwent laminectomy and intradural exploration. RESULT: On surgical exploration, a serpentine, massively dilated vein was identified, which distorted the normal nerve roots. CONCLUSION: A venous varix should be considered in the differential diagnosis of an intradural lesion in the lumbar spine in the appropriate clinical setting.

BACKGROUND AND PURPOSE/OBJECTIVE:Reproducible measurements of brain tumor volume are helpful in evaluating the response to therapy and the need for changing treatment plans. Our purpose was to adapt the fuzzy-connectedness segmentation technique to measure tumor volume. This technique requires only limited operator interaction. METHODS:Routine postoperative brain MR imaging was performed in 19 patients with primary malignant gliomas of the brain. Segmentation was performed on axial and coronal gadolinium-enhanced and axial fluid-attenuated inversion recovery (FLAIR) images by using a fuzzy-connectedness algorithm, and tumor volumes were generated. Operator interaction was limited to selecting representative seed points within the tumor and, if necessary, editing the segmented image to include or exclude improperly classified regions. RESULTS:Measurements of tumor volume were highly reproducible when they were obtained with no editing; intraobserver coefficients of variation were 0.15-0.37% and 0.29-0.38%, respectively, for enhanced images and FLAIR images. Editing consistently produced smaller volumes, at the cost of greater variability in volume measurements. Coefficients of variation for volumes with editing ranged from 0.2% to 1.3%. CONCLUSIONS:Fuzzy-connected segmentation permits rapid, reliable, consistent and highly reproducible measurement of tumor volume from MR images with limited operator interaction.

The authors describe a 36-year-old man with Sturge-Weber syndrome who presented with focal seizures and subsequently developed a temporary post-ictal hemianopia. Magnetic resonance imaging of the brain demonstrated focal leptomeningeal enhancement, which subsequently resolved.