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C R Jack

Publications and source records attributed to C R Jack.

131 records · Page 8Linked to original sources
PubMedDate not supplied

Angiographic features of gliosarcoma.

Gliosarcoma is a brain neoplasm that is being recognized with increasing frequency. We discuss the radiographic findings in 14 pathologically proven cases. At angiography in nine cases, four showed mixed dural and pial vascular supply to the lesion. Early cortical venous drainage, irregular tumor vessels, and a prominent vascular stain with well-defined tumor margins were seen in the majority of cases. CT showed an irregular enhancing rim surrounding a necrotic center in 14 cases. Most lesions were peripherally located and invaded dura.

Aged↗
PubMedDate not supplied

Cerebral angiography in brainstem revascularization.

Surgical management of patients with vertebrobasilar insufficiency has been developed within the past decade. Cerebral angiography plays a crucial role in identifying potential surgical candidates and in directing the surgical approach. Fifty-two patients underwent brainstem revascularization procedures at Henry Ford Hospital between November 1979 and August 1985. Twelve occipital artery to anterior inferior cerebellar artery bypasses, five occipital artery to posterior inferior cerebellar artery bypasses, four intracranial vertebral endarterectomies, 29 superficial temporal to superior cerebellar artery bypasses, and two superficial temporal to posterior cerebral artery bypasses were performed. The preoperative angiograms in these patients were analyzed to illustrate how angiographic localization of vascular disease directs the surgical approach. We report the results of postoperative angiograms. Technical features of the various surgical procedures, the role of the neuroradiologist, and several features of the angiographic technique used with these patients are described.

Adult↗
PubMedDate not supplied

Polyvinyl alcohol sponge for embolotherapy: particle size and morphology.

The size and morphology of particulate polyvinyl alcohol (PVA) sponge prepared by a blender technique for embolotherapy were analyzed by light and scanning electron microscopy. Techniques for preparation and sizing of PVA sponge particles are described. Two types of particulate material, differing in both size and morphology, were found. Large particles (greater than 50 micron) had irregular shapes and sharp, jagged edges. Smaller particles (2-50 micron) were more numerous. Attempts to characterize the smaller particles were unsuccessful. Preparation of PVA sponge particles using the blender technique is a viable choice in external carotid neuroembolization procedures. However, the potential effects of small particles possibly causing cranial nerve palsies does need consideration.

Animals↗
PubMedDate not supplied

Correlation of single photon emission CT with MR image data using fiduciary markers.

PURPOSE: To describe our approach to mapping the functional information provided by single photon emission computed tomography (SPECT) onto the anatomic template provided by MR, and to determine both the number of markers required to achieve accuracy and the impact of voxel shape on accuracy. METHODS: Point-to-point iterative minimization using externally fixed fiducial markers was involved and computer simulations were performed. Two types of validation studies were performed using a phanton using a phantom of known dimensions. First, the spatial distortion that may be present in MR was investigated for spin-echo and gradient-recalled echo images. Next, the accuracy with which the SPECT image could be transformed to match the MR template was analyzed. The method is also demonstrated in four cases of patients with epilepsy. RESULTS: Computer simulations indicated that for voxel dimensions we expected to use, eight fiduciary markers would consistently produce acceptable accuracy. Simulations also showed that more isotropic voxels would be more accurate if voxel volume is held constant. The spatial accuracy of both spin-echo and gradient-recalled echo images of a phantom was accurate to within 3 mm. When the SPECT image of the same phantom was correlated with the MR image using this technique, internal marker errors were never greater than 3 mm, and the mean error was 2.2 mm. CONCLUSIONS: Images from different modalities can be accurately correlated using multiple fiduciary markers. SPECT and MR images of the given dimensions can be correlated to within 3 mm. The technique aids in clarification of the nature of SPECT perfusion abnormalities and in their anatomic localization.

Brain↗