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ABSTRACT: BACKGROUND AND PURPOSE:IIH is a syndrome of elevated intracranial pressure without hydrocephalus, mass, or identifiable cause. Diagnosis is made by clinical presentation, intracranial pressure measurement, and supportive imaging findings. A subset of patients with IIH may have tonsillar ectopia, meeting the criteria for Chiari malformation type I but not responding to surgical decompression for Chiari I. The purpose of this study was to determine the incidence and morphology of cerebellar tonsillar ectopia in patients with IIH.MATERIALS AND METHODS:Forty-three patients with clinically confirmed IIH and 44 age-matched controls were included. Two neuroradiologists with CAQs reviewed sagittal T1-weighted MRI in a blinded fashion and measured cerebellar tonsil and obex positions relative to the foramen magnum and prepontine cistern width at the level of the midpons.RESULTS:Nine of 43 patients with IIH and 1/44 controls had cerebellar tonsillar ectopia of ≥5 mm. Five of 9 of patients with IIH with ectopia of ≥5 mm also had a "peglike" tonsil configuration. Patients with IIH had a significantly lower tonsillar position (2.1 ± 2.8 mm) than age-matched controls (0.7 ±1.9 mm, P < .05). The obex position was significantly lower in patients with IIH versus controls (-7.9 mm [above the FM] versus -9.4 mm [above the FM], P < .05). The prepontine width was not significantly different between the groups.CONCLUSIONS:Cerebellar tonsil position in patients with IIH was significantly lower than that in age-matched controls, often times peglike, mimicking Chiari I. A significantly lower obex position suggests an inferiorly displaced brain stem and cerebellum. When tonsillar ectopia of >5 mm is identified, imaging and clinical consideration of IIH are warranted to avoid misdiagnosis as Chiari I.
American Journal of Neuroradiology 06/2012; · 2.93 Impact Factor
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American Journal of Neuroradiology 11/2010; 32(1):E19; author reply E20. · 2.93 Impact Factor
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ABSTRACT: Skull base defects can result in CSF leaks, with meningitis as a potential complication. Surgeons are now routinely repairing these leaks via a nasal endoscopic approach. Accurate preoperative imaging is essential for surgical planning. A variety of imaging regimens have been employed, including axial and direct coronal CT, CT cisternography with iodinated contrast, radionuclide cisternography, and MR imaging. Now that multidetector helical CT is available, the purpose of this study was to determine how well coronal and sagittal multiplanar reformatted (MPR) images generated from a high-resolution axial dataset correlate with intraoperative findings in a group of patients with clinically proved CSF leaks.
We retrospectively reviewed imaging findings and surgical records of 19 patients who presented to our tertiary care institution during a 2.5-year period with clinically proved CSF leak. Patients underwent preoperative imaging with high-resolution helical CT (section collimation, 10 patients with 0.625-mm and 9 patients with 1.25-mm images), with MPR images processed by a neuroradiologist at a workstation. Two neuroradiologists, blinded to the intraoperative findings, determined the location and size of the skull base defects. All patients underwent endoscopic evaluation by an experienced sinonasal otolaryngologist, who confirmed the site of the CSF leak by direct inspection and measured the corresponding osseous defect. CT was considered accurate if it correctly localized the CSF leak and was within 2 mm of the endoscopic measurement.
At endoscopy, 22 leaks of CSF were identified in 18 of 19 patients. CT correctly predicted the site of the leak in 20 (91%) of 22 cases and was accurate (within 2 mm of the endoscopic measurement) in 15 (75%) of 20 cases preoperatively localized. The CT measurement of the skull base defect differed from the endoscopic size in 5 (25%) of 20 cases, ranging from 7.4 mm below to 13 mm above the intraoperative measurement. When analysis was limited to the subgroup of 10 patients who had 0.625-mm axial images, the accuracy was improved, and of the 11 CSF leaks described at CT, all were verified at endoscopy. In addition, the submillimeter CT accurately measured the size of the osseous defect in 9 (82%) of 11 cases. In the remaining 2 (18%) of 11 cases, CT minimally overestimated the size of the osseous defect by only 3 mm.
Axial images, and coronal, sagittal, and oblique MPR images generated from high-resolution axial CT performed well preoperatively, localizing the skull base defect responsible for the CSF leak. However, active manipulation of the axial dataset at a workstation is crucial in identifying and correctly describing these lesions. When submillimeter collimation is available, measurement of the osseous defects are accurate most of the time.
American Journal of Neuroradiology 04/2008; 29(3):536-41. · 2.93 Impact Factor
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ABSTRACT: Pulsatile tinnitus (PT), a common disorder, can be caused by a variety of otologic and vascular lesions. Various imaging modalities, including CT, MR imaging and angiography, and conventional angiography, have been used in the assessment of PT. Ideally, a single imaging study to evaluate for the largest variety of etiologies would be optimal. In our study, we examine the potential for CT arteriography and venography (CTA/V) in the evaluation of PT.
Sixteen patients with PT were prospectively evaluated by an otolaryngologist, had a normal otologic examination, and were referred for a CTA/V. All examinations were performed on a 16-section multidetector CT. The carotid bifurcations, internal carotid artery course, transverse and sigmoid sinuses, jugular foramen, internal jugular vein, sella turcica, and temporal bones were evaluated.
Seven of the 16 patients had lesions on CTA/V that could account for their PT. Examples of pathologic conditions in the series included a significantly dominant venous system, a venous diverticulum with stricture, and a transverse sinus stenosis.
Preliminary findings indicate that CTA/V can be a valuable imaging tool in the assessment of PT. With this technique, arterial, venous, middle, and inner ear causes of PT can be excluded.
American Journal of Neuroradiology 10/2006; 27(8):1635-8. · 2.93 Impact Factor
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ABSTRACT: This paper describes the CT findings that characterize the middle and inner ear anomalies in coloboma, heart defects, choanal atresia, mental retardation, genitourinary, and ear anomalies (CHARGE) syndrome. With this information, neuroradiologists will be better prepared to provide clinically relevant information to their referring physicians regarding this rare syndrome.
CT studies from 13 patients were reviewed by 2 neuroradiologists with Certificate of Additional Qualification. Each ear was counted separately for a total of 26 ears. Middle and inner ear anomalies associated with CHARGE syndrome were categorized. Investigational review board approval was obtained.
Twenty of 26 (77%) ears demonstrated cochlear aperture atresia. Four of these ears were evaluated with MR imaging and were found to lack a cochlear nerve. Twenty-one of 26 (81%) cochlea had some form of dysplasia. Six of 26 (23%) round windows were aplastic. Three of 26 (12%) round windows were hypoplastic. Twenty-one of 26 (81%) oval windows were atretic or aplastic. Fifteen of 26 (58%) vestibules were hypoplastic or dysplastic. There were 5 of 26 (19%) enlarged vestibular aqueducts. Twelve of 26 (46%) vestibular aqueducts had an anomalous course. All cases demonstrated absent semicircular canals. Twenty-three of 26 (88%) facial nerve canals had an anomalous course. Four of 26 (15%) tympanic segments were prolapsed. Three of 26 (12%) temporal bones had an anomalous emissary vein referred to as a petrosquamosal sinus. Twenty-one of 26 (81%) middle ear cavities were small. Twenty-three of 26 (93%) ossicles were dysplastic with ankylosis. Three of 26 (12%) internal auditory canals were small.
The CT findings that correlate to the anomalies of CHARGE syndrome affect conductive as well as sensorineural hearing. Stenosis of the aperture for the cochlear nerve aperture on CT is suggestive of hypoplasia or absence of the cochlear nerve, which has been demonstrated in some cases by MR. Absence of the cochlear nerve would be a contraindication to cochlear implantation.
American Journal of Neuroradiology 10/2006; 27(8):1663-71. · 2.93 Impact Factor
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ABSTRACT: This case report suggests that magnetic resonance imaging with diffusion weighted imaging may help distinguish between tumour recurrence and radiation induced necrosis in patients previously treated for a brain tumour.
Journal of Neurology Neurosurgery & Psychiatry 04/2003; 74(3):382-4. · 4.76 Impact Factor
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ABSTRACT: A fast spin-echo inversion-recovery (FSE-IR) sequence is described for its utility regarding surgical planning for patients with Parkinson's disease (PD) who are undergoing microelectrode-guided internal globus pallidus (GPi) ablation. Images from thirty-seven adult patients with PD were reviewed and visualization of the GPi, globus pallidus externa (GPe), and the intervening lamina was noted. High-resolution images were acquired from all patients despite the external hardware and the patients' movement disorder. In all cases, the conventional surgical trajectory, determined indirectly by a fixed measurement from the anteroposterior commissure line, was modified by the ability to visualize the GPi and optic tract directly. This sequence facilitated accurate stereotactic targeting.
American Journal of Neuroradiology 06/2000; 21(5):928-31. · 2.93 Impact Factor
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American Journal of Roentgenology 04/2000; 174(3):874-5. · 2.78 Impact Factor
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ABSTRACT: Muslin-induced optic neuropathy is a rarely reported but important cause of delayed visual loss after repair of intracranial aneurysms. Most of the previously reported cases were published before the introduction of MR imaging. We describe the clinical features and MR appearance of two cases of delayed visual loss due to "muslinoma," and compare them with the 21 cases reported in the literature.
American Journal of Neuroradiology 03/2000; 21(2):346-52. · 2.93 Impact Factor
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P A Hudgins
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ABSTRACT: In the pediatric neck, inflammatory processes are common and usually are nodal in origin. Virtually every pediatric infection, including viral diseases, can result in dramatic cervical adenopathy. The differential diagnosis for a dominant pediatric node, however, is different from that in adults, with neoplastic disease occurring less frequently. When nonnodal cervical infections or abcesses occur, it is important to identify the source and involvement of major vessels, the airway, and the mediastinum. This article reviews common nodal processes and the complications of suppurative adenopathy. Nodal and nonnodal inflammatory processes are discussed, with emphasis on the clinical presentation and common imaging findings.
Neuroimaging Clinics of North America 03/2000; 10(1):181-92, ix. · 1.51 Impact Factor
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ABSTRACT: Technical developments in magnetic resonance imaging of the brain and orbits provide a challenge to radiologists and practicing clinicians alike. Several new trends in brain imaging are reviewed, including fluid-attenuated inversion recovery (FLAIR), diffusion-weighted imaging (DWI), and perfusion and functional magnetic resonance imaging. These techniques are increasingly used in the clinical environment. Two innovative magnetic resonance techniques for imaging the orbit are also reviewed.
Current Opinion in Ophthalmology 01/1999; 9(6):54-60. · 2.65 Impact Factor
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ABSTRACT: Three patients with the diagnosis of acute calcific prevertebral tendinitis underwent CT or a combination of CT and MR imaging, which showed previously described findings of calcifications within the tendons of the longus colli muscles. In addition, however, we detected a retropharyngeal effusion in all three patients. The importance of this finding lies in the need to differentiate this effusion from retropharyngeal infection.
American Journal of Neuroradiology 11/1998; 19(9):1789-92. · 2.93 Impact Factor
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ABSTRACT: Despite improvements in the care of preterm infants, intraventricular hemorrhage (IVH) and posthemorrhagic hydrocephalus (PHH) continue to be frequent occurrences in this patient population. Shunt procedures in these children are frequently complicated by obstruction and/or infection. As the hydrocephalus is usually caused by an obliterative arachnoiditis due to contact of the blood with the basilar meninges, it was postulated that infusion of urokinase into the ventricles of infants who have sustained an IVH would clear the blood, mitigate the arachnoiditis, and prevent the progression of PHH. Accordingly, 18 preterm infants who had sustained IVH and subsequently developed PHH were treated with intraventricular urokinase instilled via a surgically implanted subcutaneous reservoir. There were no complications associated with the urokinase. Infants were divided into two dosage groups: low dose (110,000-140,000 IU total) and high dose (280,000 IU total). One infant in the low-dose group died at 1 month of life of respiratory complications. In the low-dose group, 3 of 8 (37%) infants required shunt placement; in the high-dose group, all 9 required shunt placement. For the total group, the shunt rate was 71%. This compares to a historical control group shunt rate of 92%. While the difference between the treatment group as a whole and control group approaches, but does not reach, statistical significance (p = 0.068), there was a significant reduction in the shunt rate when the low-dose group was considered separately (p < 0.002). For those infants that required shunt placement, there were fewer shunt revisions performed in the treatment group than in the control group during the first 24 months following shunt placement: 0.67 versus 1.5 shunt revisions/shunted child. Initial experience with intraventricular urokinase following IVH and PHH in preterm infants suggests a beneficial effect in reducing the shunt revision rate in both high- and low-dose groups. Reduction in shunt placement rate is seen only in the low-dose group.
Pediatric Neurosurgery 06/1997; 26(6):281-7. · 0.70 Impact Factor
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ABSTRACT: To review the intracranial and facial imaging features in children with congenital anophthalmos.
We retrospectively studied eight children with anophthalmos with respect to intraorbital, intracranial, and craniofacial anomalies (six had CT examinations, including the face, orbits, and brain, and four had MR imaging, including the orbits and brain).
Three patients had primary bilateral anophthalmos on CT (n = 1) and MR (n = 3) studies. In these patients, MR images showed hypoplasia of the optic chiasm and posterior visual pathways (n = 3), agenesis (n = 1) or dysgenesis of the corpus callosum (n = 2), and a mass in the tuber cinereum region (n = 1). One patient had incontinentia pigmenti. Five patients had unilateral anophthalmos on CT (n = 5) and MR (n = 1) studies. One of these patients had a contralateral congenital cystic eye and one had contralateral severe microphthalmia and absent optic chiasm. All had craniofacial anomalies that consisted of midline facial clefts (n = 2) and concomitant hemifacial hypoplasia (n = 2). One had a craniosynostosis. All five had normal-appearing brains.
Patients with bilateral anophthalmos represent a distinct group from those with unilateral anophthalmos. In our patients, bilateral anophthalmos was associated with absence of the optic chiasm, diminished size of the posterior optic pathways, and agenesis or dysgenesis of the corpus callosum. Patients with unilateral anophthalmos had severe craniofacial anomalies. Imaging of the face is helpful in patients with unilateral anophthalmos.
American Journal of Neuroradiology 04/1997; 18(3):555-61. · 2.93 Impact Factor
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ABSTRACT: To determine the MR and CT appearance of the normal pediatric larynx.
Fifteen CT scans and 15 MR examinations of children with normal larynges and airways were reviewed retrospectively. Characteristics that were noted included the level of the hyoid bone, calcification and signal intensity within separate laryngeal components, amount of paraglottic fat, anteroposterior airway diameters, and airway contours. Two cadaveric larynges were imaged by CT and MR and were then sectioned at corresponding levels and section thicknesses.
The larynx is higher in children than in adults, with the hyoid bone found at the C2-3 level in the youngest children (newborn to 2 years). The subglottic airway was narrowest in the youngest children. The hyoid bone was the only laryngeal structure ossified in any of the children. A thin line of high density was seen in the expected location of the thyroid cartilage in some children. The featureless circumferential soft tissue seen around the airway represented the uncalcified laryngeal cartilaginous structures. This was confirmed on gross sectioning of cadaveric larynges. The supraglottic airway contour was triangular or oval, the glottis was shaped like a teardrop, and the subglottic contour was oval. Contours were confirmed on histologic examination of necropsy specimens.
This preliminary study suggests that the pediatric larynx differs from the adult larynx with respect to size, position, consistency, and shape, and these differences are reflected on CT and MR studies.
American Journal of Neuroradiology 03/1997; 18(2):239-45. · 2.93 Impact Factor
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P A Hudgins
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ABSTRACT: Recent changes in sinonasal imaging are a direct result of the development of functional endoscopic sinus surgery. Because of this technique, radiologists have noted an increased volume of sinus imaging, developed new imaging techniques, and are interpreting films in a different manner. This article covers the common variants seen on coronal computed tomography, discusses the complications of functional endoscopic sinus surgery, reviews the radiographic criteria for sinusitis, and addresses the role of computed tomography and magnetic resonance imaging in evaluating the sinonasal cavity.
Neuroimaging Clinics of North America 06/1996; 6(2):319-31. · 1.51 Impact Factor
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American Journal of Neuroradiology 06/1995; 16(5):1161-3. · 2.93 Impact Factor
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ABSTRACT: 1. A sample of 165 schizophrenic subjects was compared to a normal control group in order to evaluate associations between white matter hyperintensity signals and vascular risk factors. 2. A comprehensive medical chart review was completed on all subjects evaluating potential vascular risk factors. Brain MRI acquisition was performed with 0.5 and 1.5 Telsa Philips scanners. 3. Prevalence rates of WMH signals in schizophrenic subjects and normal controls were 4.8% and 4.9%, respectively. 4. A significant association was found for schizophrenics with WHM signals to schizophrenics without signals for hypertension and history of CVA's. 5. This finding is consistent with an etiology of WMH signals in schizophrenia being related to vascular disease.
Progress in Neuro-Psychopharmacology and Biological Psychiatry 02/1995; 19(1):39-45. · 3.25 Impact Factor
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ABSTRACT: The purpose of this study was to report the clinical and imaging findings of seven children who developed extraaxial, intracranial hemorrhage 3-12 years after suboccipital craniectomy for neoplasia. We attempt to explain the hemorrhages based on a previously reported hypothesis of neomembrane formation associated with dural substitutes used to repair large dural defects.
Clinical charts (seven patients), surgical and pathologic findings (four patients), and imaging studies (CT scans and MR images in four; CT scans, MR images, and angiograms in one; and CT scans only in two patients) were reviewed retrospectively. Hemorrhage occurred 3-12 years after suboccipital craniectomy for tumor (ependymoma in two, medulloblastoma in three, astrocytoma in one, and ganglioglioma in one). Silastic dural substitute was used to repair the surgical wound in six cases and human dural graft in one case. Hematomas were spontaneous in four and occurred after minor head trauma in three. Four patients had multiple hemorrhagic episodes.
CT scans and MR images showed acute extraaxial hemorrhages at the craniectomy site without contiguous residual or recurrent neoplasia in all patients. No intraaxial or intratumoral hemorrhage was detected. Findings on cerebral angiograms in one patient were normal. Four patients underwent surgical exploration of the hematoma and craniectomy site; no macroscopic source of bleeding was detected. The hematomas were not associated with recurrent tumor pathologically.
Delayed, benign extraaxial hematomas may occur in children who have undergone craniectomy for tumors of the posterior fossa and have had dural substitute used to repair large defects. Fragile vessels associated with nonmembranes have been proposed as the source of hemorrhage.
American Journal of Roentgenology 11/1994; 163(4):897-900. · 2.78 Impact Factor
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ABSTRACT: To describe the appearance of recurrent malignant neoplasms in patients who have undergone resection of primary head and neck tumors with flap reconstruction.
Thirty-two examinations, 26 CT and 6 MR scans, were retrospectively reviewed in 25 patients with documented recurrent malignant neoplasms. Confirmation of disease was by biopsy or disease progression. The flaps included 15 myocutaneous, 6 free composite, 2 jejunal free grafts, and 2 combined jejunal and myocutaneous flaps.
The most common location of recurrence was in the primary tumor bed involving the undersurface or suture line of the reconstruction flaps, 14 of 32 scans; both nodal and flap recurrence was seen in 12 of 32 scans.
When examining patients who may have recurrent disease after flap reconstruction, the radiologist should be aware of the type of flap used and the expected appearance. Tumor recurrence in this patient population is manifest either as a focal recurrent mass at or near the suture line of the reconstruction flap, or nodal disease, usually in the contralateral neck.
American Journal of Neuroradiology 11/1994; 15(9):1689-94. · 2.93 Impact Factor
