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BACKGROUND AND PURPOSE: The spinal cord is a site of predilection for MS lesions. While diffusion tensor imaging is useful for the study of anisotropic systems such as WM tracts, it is of more limited utility in tissues with more isotropic microstructures (on the length scales studied with diffusion MR imaging) such as gray matter. In contrast, diffusional kurtosis imaging, which measures both Gaussian and non-Gaussian properties of water diffusion, provides more biomarkers of both anisotropic and isotropic structural changes. The aim of this study was to investigate the cervical spinal cord of patients with MS and to characterize lesional and normal-appearing gray matter and WM damage by using diffusional kurtosis imaging. MATERIALS AND METHODS: Nineteen patients (13 women, mean age = 41.1 ± 10.7 years) and 16 controls (7 women, mean age = 35.6 ± 11.2-years) underwent MR imaging of the cervical spinal cord on a 3T scanner (T2 TSE, T1 magnetization-prepared rapid acquisition of gradient echo, diffusional kurtosis imaging, T2 fast low-angle shot). Fractional anisotropy, mean diffusivity, and mean kurtosis were measured on the whole cord and in normal-appearing gray matter and WM. RESULTS: Spinal cord T2-hyperintense lesions were identified in 18 patients. Whole spinal cord fractional anisotropy and mean kurtosis (P = .0009, P = .003), WM fractional anisotropy (P = .01), and gray matter mean kurtosis (P = .006) were significantly decreased, and whole spinal cord mean diffusivity (P = .009) was increased in patients compared with controls. Mean spinal cord area was significantly lower in patients (P = .04). CONCLUSIONS: Diffusional kurtosis imaging of the spinal cord can provide a more comprehensive characterization of lesions and normal-appearing WM and gray matter damage in patients with MS. Diffusional kurtosis imaging can provide additional and complementary information to DTI on spinal cord pathology.

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OBJECTIVE: To determine the incidence and type of neuroimaging abnormalities in children presenting with a first seizure. METHODS: In a prospective observational study, 411 children with a first afebrile seizure were seen between 1983 and 1992. Imaging studies were performed in 218 (53%). For this analysis we examined the most sensitive neuroimaging study performed which included 159 computed tomography scans and 59 magnetic resonance imagings (MRI). RESULTS: Four children were found to have lesions requiring intervention (brain tumor in two, neurocysticercosis in two). The remaining 407 were enrolled in a follow-up study of children with a first unprovoked seizure. After a mean follow-up of >10 years, none have developed clinical evidence of a tumor. In these 411 children, 45 (21%) of 218 imaging studies were abnormal. The most common abnormalities were focal encephalomalacia (n=16) and cerebral dysgenesis (n=11). Although children with partial seizures were more likely to be imaged (64%) than children with generalized seizures (43%) (P<0.001), the fraction of abnormal imaging studies was similar in both groups. Six children with a normal neurological examination who were initially classified as cryptogenic were subsequently found to have errors of cerebral migration on MRI. The incidence of lesions requiring acute intervention in children presenting with a first seizure is low. A significant proportion will have neuroimaging abnormalities particularly on MRI. CONCLUSIONS: Neuroimaging should be considered in any child with a first seizure who does not have an idiopathic form of epilepsy.

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BACKGROUND: Central nervous system involvement is a common manifestation of non-Hodgkin lymphoma (NHL) in human immunodeficiency virus (HIV)-infected individuals. The purpose of this study was to review the frequency and pattern of neurologic manifestation of lymphoma in a cohort of HIV-infected individuals with systemic NHL. METHODS: Sixty-two patients with HIV-associated systemic NHL received infusional cyclophosphamide, doxorubicin, and etoposide. Five patients with lymphomatous meningitis at presentation received whole brain radiation therapy plus intrathecal chemotherapy (ITC). Of the remaining 57 patients, prophylactic ITC was recommended only for those patients with lymphomatous bone marrow involvement and/or high grade histology (N = 31). RESULTS: Thirteen patients (21%) had histologically documented (N = 6) or presumed (N = 7) central nervous system involvement, including 7 patients (11%) with meningeal lymphoma discovered either at presentation (N = 5) or soon after diagnosis (N = 2), and 6 patients (10%) with cerebral mass lesions at the time of disease recurrence consistent with parenchymal brain involvement. Five of six parenchymal brain recurrences occurred in the setting of progressive systemic disease. Four of 7 patients (57%) with meningeal lymphoma detected at presentation (N = 5) or within 3 months of presentation (N = 2) responded to therapy and survived >1 year. Of the 26 patients assigned to receive no prophylactic ITC, no patient developed an isolated meningeal recurrence and 1 patient developed an isolated parenchymal brain recurrence. CONCLUSIONS: The findings of the current study suggest that in patients with HIV-associated systemic lymphoma, meningeal lymphoma is potentially curable, parenchymal brain recurrence usually occurs in the setting of uncontrolled systemic disease, and prophylactic ITC may not be necessary for patients with intermediate grade histology and uninvolved bone marrow.

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The widespread use of highly active antiretroviral therapy (HAART) since 1996 has led to a substantial decline in morbidity and mortality in patients infected with HIV, although its effect on the incidence of HIV-associated malignancies is unknown. We retrospectively reviewed the annual number of outpatient visits to our HIV clinic, inpatient admissions for HIV disease, and first admissions for patients with cancer and HIV disease at our center between 1990 and 1997. Between 1990 and 1995, there was a progressive increase in the annual number of admissions for HIV disease and HIV-associated cancers that paralleled the increasing HIV clinic volume. In 1997, however, the annual number of first admissions for Kaposi's sarcoma (KS) and non-Hodgkin's lymphoma compared with 1995 decreased by 36% and 63%, respectively, despite a continued increase in the annual number of HIV clinic visits. Similar declines were also noted in the number of new cases of biopsy-confirmed KS and primary central nervous system (CNS) lymphoma. In contrast, there was no decrease in the number of first admissions for patients with HIV infection and other cancers not typically associated with HIV infection. These findings suggest a declining incidence of HIV-associated malignancies since the introduction of HAART.

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PURPOSE: We propose to present a novel case of a genital malignancy metastatic to the head and neck. Carcinoma of the uterine cervix is the third most frequent malignancy of the female genital tract. Early detection and improved radiation and surgical techniques have resulted in better control of the pelvic tumor and a greater incidence of distant metastasis. Metastases to the soft tissue of the head and neck region have not been reported. METHODS: We present the first known case of a 35-year-old woman with cancer of the uterine cervix who presented with metastasis to the soft tissue behind the zygomatic arch. RESULTS: The patient received radiation therapy to the zygomatic region and cisplatin therapy with a near-complete remission. CONCLUSION: This case shows that not all squamous cell cancers detected above the clavicles are from a thoracic or a head and neck primary tumor. The atypical location should alert the physician to suspect distant metastasis, rather than locoregional disease.

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PURPOSE: To determine if lucanthone crossed the blood-brain barrier in experimental animals; and to determine accelerated tumor regression of human brain metastases treated jointly with lucanthone and whole brain radiation. METHODS AND MATERIALS: The organ distribution of 3H lucanthone in mice and 125I lucanthone in rats was determined to learn if lucanthone crossed the blood-brain barrier. Size determinations were made of patients' brain metastases from magnetic resonance images or by computed tomography before and after treatment with 30 Gy whole brain radiation alone or with lucanthone. RESULTS: The time course of lucanthone's distribution in brain was identical to that in muscle and heart after intraperitoneal or intravenous administration in experimental animals. Lucanthone, therefore, readily crossed the blood-brain barrier in experimental animals. CONCLUSION: Compared with radiation alone, the tumor regression in patients with brain metastases treated with lucanthone and radiation was accelerated, approaching significance using a permutation test at p = 0.0536.

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The standard treatment for patients with primary malignant glioma includes surgical resection, radiotherapy, and nitrosourea. Despite this multimodality approach, adults with newly diagnosed glioblastoma multiforme (GBM) and high-grade astrocytoma have a median survival duration of 50 weeks and 150 weeks respectively. Chemotherapy has had a limited impact on the survival of these patients. Merbarone (5-phenylcarboxamide-2-thiobarbituric acid) is a nonsedating derivative of barbituric acid that crosses the blood brain barrier. Antitumor activity of merbarone has been described against L1210, B16 melanoma cell line and the M5076 sarcoma cells in phase I studies. Merbarone inhibits DNA synthesis and tumor growth by inducing single strand breaks in DNA. It also inhibits RNA and protein synthesis. We evaluated merbarone in a phase II trial in patients (pts) with recurrent or refractory GBM (7 pts) and high grade anaplastic astrocytoma (7 pts). Fourteen patients (nine males, five females) were treated with merbarone at a dose of 1000 mg per m2 per day by continuous intravenous infusion for 5 days every 3 weeks. Every patient received at least two cycles of treatment. No complete or partial responses were observed, although one patient had stable disease lasting 20 weeks. Our conclusion is that merbarone is ineffective against GBM and high-grade anaplastic astrocytoma at the dose and schedule in which it was administered in this trial.

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PURPOSE: The purpose of this study was to evaluate the accuracy and reproducibility of linear measurements obtained from three-dimensional reconstructions of computed tomography (CT) scans. MATERIALS AND METHODS: Ten rectangular acrylic blocks were prepared with titanium molybdenum alloy (TMA) markers spaced from 1 to 10 mm, respectively. A plastic sphere was prepared with 10 sets of TMA markers spaced at variable intervals of 1 to 10 mm. Each object was scanned three times at 3-mm slice thicknesses and 1.5 mm with 0.5 mm overlap slice thicknesses, as well as positioned in the CT scanner in two different directions (perpendicular and parallel) to the scanning beam. Intermarker distances of the reconstructed objects were then measured using the measurement tool of the MediCAD software and compared with measurements taken by hand with a vernier caliper. RESULTS: Using the 3-mm cut protocol, the data indicated that inconsistency exists between intermarker distance in the scans when the rectangular objects were scanned parallel to the scanning beam. This finding was not seen using the 1.5-mm with 0.5-mm overlap slice thickness protocol. The intermarker distances for objects scanned perpendicular to the scanning beam were consistent but subject to demagnification in the range of 17% to 20% for both scanning protocols. CONCLUSION: The orientation of the object to the scanning beam and slice thickness protocol appear to have an impact on the accuracy and variability of linear measurements taken in the x, y, z axes.

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Twenty consecutive patients with velocardiofacial syndrome underwent magnetic resonance angiography (MRA) to determine if abnormalities of the neck arteries would contraindicate pharyngeal flap surgery. All 20 patients were found to have anomalies to the carotid arteries, vertebral arteries, medially placed internal carotids, low carotid bifurcations, and tortuous or kinked internal carotids. The internal carotids were found to be almost directly under the mucous membrane of the pharynx in two patients. In these two patients, the arteries were close to the pharyngeal midline at the base of the first cervical vertebra and might easily be severed during the raising of a pharyngeal flap. Hypoplastic vertebral arteries also were found. One patient had an extra neck vessel. The anomalies of the internal carotids did not have a strong correlation with endoscopically observed pulsations in the position affected the location of the internal carotids did not have a strong posterior pharyngeal wall. It also was found that head position affected the location of the internal carotid arteries when they were located close to the pharyngeal mucous membrane. The information provided in the MRA studies allowed assessment of the arterial anomalies in relation to the flap donor site so that the patients in the sample who underwent pharyngeal flap surgery using a short superiorly based flap had no major bleeding complications.

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BACKGROUND: Multicystic benign lymphoepithelial lesions of the parotid gland (BLL) seen in patients with human immunodeficiency virus (HIV) can produce considerable cosmetic deformity as well as physical discomfort. We previously reported our preliminary results with low-dose radiotherapy in this disease, and all 8 patients were satisfied with the initial improvement in their appearance. We now report the long-term follow-up of those patients and additional patients. METHODS: Twelve HIV-positive patients with BLL were treated with 8-10 Gy of external radiation using 2-Gy daily fractions. Objective responses and subjective duration of patient-defined cosmetic control were recorded. RESULTS: All 12 patients (100%) had at least a 50% decrease in the size of their parotid masses. Five of 12 (42%) had a complete response and 7 (58%) had a partial response. Persisting complete response was achieved in only 1 patient, however, with relapse in the other 11 patients. Cosmetic palliation, as judged by the patients, was achieved for a median of 9.5 months. Eight patients were subsequently retreated with doses of 6-16 Gy (median and mode: 10 Gy). None (0%) of the 8 patients retreated achieved local control. CONCLUSIONS: Very low-dose radiation (8-10 Gy) provides reliable but temporary cosmetic palliation for BLL. Retreatment was unsatisfactory, and we are now investigating higher initial doses of radiation to prolong palliation and eliminate recurrences.

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OBJECTIVE: To compare the amount of scatter produced by titanium plates versus Vitallium (Howmedica, Rutherford, NJ) plates. Software was also evaluated to determine its effectiveness in removing the scatter and clarifying the underlying anatomy. MATERIALS AND METHODS: Miniplating and microplating systems composed of Vitallium or titanium were placed on the nasal and frontal bones of three adult pig heads. A computerized axial tomography (CAT) scan was then performed and a three-dimensional CAT scan was reconstructed using MediCad software (MediCad Inc, Cedar Knolls, NJ). The amount of scatter for each plating system was quantitated using the MediCad software measuring tool. The scatter was removed and the three-dimensional CAT scan was reconstructed to assess the clarification of the underlying anatomy. RESULTS: No scatter was found with either the miniplating or the microplating system composed of titanium. The Vitallium plates did show significant amount of scatter with the mini, micro, and micromesh system. Removal of the scatter resulted in slight improvement in the anatomic detail. CONCLUSION: Titanium plating systems do not cause any radiation scatter. The MediCad software system allows removal of the scatter found with the Vitallium plates, which helps clarify the underlying anatomy.

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Magnetic resonance imaging of the brain in 11 consecutively referred patients with velo-cardiofacial syndrome (VCF) showed anomalies in nine cases including small vermis, cysts adjacent to the frontal horns, and small posterior fossa. Focal signal hyperintensities in the white matter on long TR images were also noted. The nine patients showed a variety of behavioral abnormalities including mild developmental delay, learning disabilities, and characteristic personality traits typical of this common multiple anomaly syndrome which has been related to a microdeletion at 22q11. Analysis of the behavioral findings showed no specific pattern related to the brain anomalies, and the patients with VCF who did not have detectable brain lesions also had behavioral abnormalities consistent with VCF. The significance of the lesions is not yet known, but the high prevalence of anomalies in this sample suggests that structural brain abnormalities are probably common in VCF.

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BACKGROUND: Anatomic barriers to the spread of laryngeal cancer include the conus elasticus, the quadrangular membrane, and the thyroid cartilage. It has been speculated that an elastic barrier surrounds and protects the ventricle. METHODS: The authors studied the microanatomic patterns of spread of 17 cases of patients who had laryngeal cancer with paraglottic disease and confirmed their findings by examining normal autopsy specimens. RESULTS: Five patients of the seventeen cases showed no ventricular mucosal involvement despite extensive paraglottic disease. Both an inner, central, subepithelial periventricular elastic membrane barrier were identified; the latter was in continuity with the conus elasticus and quadrangular membrane. CONCLUSIONS: Two weak fibroelastic barriers surround the ventricle. The outer, peripheral, fibroelastic membrane is contiguous with the conus elasticus and the quadrangular membrane. Therefore, ventricular involvement is not a sensitive indicator of paraglottic spread. Squamous cell cancer may grow around the periventricular barriers to involve both the true and false cords but may spare the ventricle. The prognostic significance of the violation or preservation of the periventricular elastic barriers is unknown.

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From the records of The Mount Sinai Hospital, seven cases which met established criteria for radiation-induced meningiomas were identified. This represents the largest series of radiogenic meningiomas documented in North America and includes both intracranial and intraspinal tumors. The records and pathological specimens were reviewed and these data analyzed with other cases retrieved from the world literature. This study reveals that radiation-induced meningiomas can be categorized into three groups based on the amount of radiation administered: 1) low dose; 2) moderate dose and miscellaneous; and 3) high dose. The overwhelming majority of cases had received low-dose irradiation (800 rad) to the scalp for tinea capitis and the second largest group resulted from high-dose irradiation for primary brain tumors (greater than 2000 rad). The unique features distinguishing radiation-induced meningiomas from other meningiomas are reviewed. Although histologically atypical tumors were common in this series, overt malignancy was not encountered. The preoperative management of these lesions should include angiography to evaluate for large-vessel occlusive vasculopathy, a known association of meningiomas induced by high-dose irradiation. Given the propensity these tumors possess for recurrence, a wide bony and dural margin is recommended at surgical resection.

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Leptomyelolipoma (lumbosacral lipoma) is a common form of spinal dysraphism. The deficits produced include sensory, motor, bowel, and bladder dysfunction, and vary in incidence between the pediatric and adult populations. Twenty patients treated surgically at the Mount Sinai Hospital between 1972 and 1988 are reviewed. Fifty percent were 12 years of age or less and 50% were older than 18 years of age. The surgical approach was designed to accomplish untethering of the conus medullaris, debulking of the lipomatous mass compressing the cord, reconstruction of the dural canal, and reapproximation of the paraspinal muscles and lumbosacral fascia to prevent future trauma. Postoperatively, no patient experienced deterioration of neurological function. Of the symptomatic patients. 67% displayed dramatic improvement or became asymptomatic and 33% experienced stabilization of their deficits. The symptoms most resistant to surgical correction were orthopedic foot deformities and bowel dysfunction, whereas bladder dysfunction, motor weakness, and radiculopathies were most amenable to surgical therapy. Early surgical repair is recommended in these cases to forestall irreversible neurological damage.

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The 29th patient with a lingual osteoma is presented. This is the first case, to our knowledge, with preoperative radiographic and computed tomographic documentation. This rare, benign tumor almost always occurs as a pedunculated solitary mass that arises from the posterior tongue near the foramen cecum. The patients are usually young women who complain wf dysphagia or fullness in the base of the tongue. The imaging findings and theories of the origin of this tumor are described.

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A special 30 degree slant-hole collimator has been developed for rotating camera single photon emission computerized tomography (SPECT) that allows the camera to remain close to the patient's head throughout a standard 360 degrees circular rotation. Compared with SPECT using parallel-hole collimation, angled-collimator SPECT (A-SPECT) yielded approximately a 30% increase in resolution without significant losses in sensitivity. The full width at half maximum in reconstructed transaxial images of Tc-99m line sources was 1.2 cm for the A-SPECT system compared with 1.6 cm for conventional SPECT, and A-SPECT yielded substantial improvements in modulation transfer function for the line source. A-SPECT images of phantoms and of patients with paranasal sinus disease were consistently superior in resolution to those of conventional SPECT. The findings suggest that A-SPECT will improve the quality of cranial images obtained with rotating camera SPECT systems.

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