Biomedical subjects
Publications and source records attributed to J F Seeger.
A tecnhique of performing metrizamide myelography with the patient supine and using lateral C1-2 puncture is described. Some advantages of this technique are discussed, especially for thoracic myelography.
Olfactory neuroblastoma is often misdiagnosed pathologically. The authors reviewed eight such cases in which the pathological findings met strict criteria. These neoplasms are locally invasive in the nose and paranasal sinuses, with frequent intraorbital and intracranial extension as well as distant metastases. A rare primary presentation in the sphenoid sinus-clivus region is described. Computed tomography is the procedure of choice in defining intraorbital extension and is complementary to precision laminagraphy for defining intracranial extension. Angiography frequently shows hypervascularity and may be of further help in assessing intracranial extension.
Complete occlusion of the cervical segment of the internal carotid artery may result in a collateral circuit between an enlarged ascending pharyngeal artery and the intracranial segment of the internal carotid artery. This anastomosis may simulate a severely stenotic or hypoplastic internal carotid artery. Differentiation between these entities is particularly important if carotid endarterectomy for relief of stenosis is contemplated.
Computed tomography (CT) in patients with oculocraniosomatic disease (OCSD) or Kearns-Sayre syndrome has not been previously reported to the authors' knowledge. CT scans were performed in 6 children and 3 adults with OCSD. Abnormalities in children included: intracranial calcifications (4 patients); white matter disease (3 patients); cerebellar hypoplasia (1 patient); and scattered areas of decreased density in the cerebellar hemispheres, mesencephalon, and thalamus (1 patient). CT scans were normal in all adults. OCSD should be considered in the differential diagnosis in patients with intracranial calcification and white matter disease.
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An arteriovenous fistula which shunted arterial blood from the circle of Willis to the internal jugular vein was created in ten monkeys. Continued patency of the shunt was confirmed angiographically. Cerebral blood flow measurements were then obtained with the shunt both open and occluded. Flow was also determined in response to elevations of systemic arterial pressure and raised arterial carbon dioxide tensions (PaCO2), again with the shunt both patent and occluded. In addition, flow through the shunt alone was measured in response to elevations of systemic arterial pressure and PaCO2. The results suggest that flow through our arteriovenous shunt is minimally autoregulated to changes in systemic arterial pressure and is only slightly responsive to changes in PaCO2.
Three cases of a basilar/middle meningeal artery anastomosis are demonstrated angiographically. No reference to previous angiographic demonstration of this vascular anomaly has been found in the literature, and only one similar case with an anatomical description has been located. An embryological explanation of this rare anastomosis is presented.
Lumbar discovertebral abnormalities thought to be due to endogenous or subclinical trauma were evaluated in 22 cases. These consisted of predominantly lytic areas due to intrabody disc herniation in five cases, broad zones of vertebral body sclerosis due to reactive osteitis in 11, and destruction of the vertebral endplates surrounded by diffuse sclerosis in six. Spinal biopsy and negative bacterial cultures were consistent with the diagnosis in eight cases. Follow-up roentgenograms and further clinical evaluation in the remaining 14 showed either no progression or changes consistent with trauma. Only four cases had a history of exogenous trauma. Intrabody disc herniations usually affected the upper vertebral body with characteristic sparing of the adjacent endplate. The sclerotic lesions tended to occur in the anterior portion of the vertebral body, with the inferior aspect of L4 most frequently involved. These may be confused with osteoblastic metastases, particularly if adjacent disc narrowing is minimal. The lack of progressive vertebral fragmentation helps to distinguish this condition from neuroarthropathy. Lesions characterized by destruction of the vertebral endplates and reactive sclerosis simulate infection; absence of a soft tissue mass and clinical signs of sepsis as well as lack of progression are important differential features.
The anatomy and angiographic appearance of the great horizontal fissure is seen on most vertebral angiograms of excellent quality and is best shown on the lateral and AP (transfacial) projections. Identification of the fissure may provide an additional angiographic landmark for precise localization of peripherally situated masses, either within or adjacent to the cerebellum.
Angiographic abnormalities of the lower hindbrain seen in 13 cases of Chiari Type I and Type II malformations are described. Previously reported findings are assessed, particularly deformities of the posterior inferior cerebellar artery (PICA). Caudal displacement of the cerebellar tonsils without other angiographic localizing signs of an expanding intracranial mass suggest a Chiari malformation. In such cases it is helpful to demonstrate a low cephalic loop of the PICA, reflecting caudal displacement of the fourth ventricle. Associated angiographic demonstration of significant intraspinal localization of the brainstem is pathognomonic of Chiari malformation.
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Explore the source record for details and available documents.
Explore the source record for details and available documents.