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V E Toro

Publications and source records attributed to V E Toro.

7 recordsLinked to original sources
PubMed1994

Computerized case-based instructional system for computed tomography and magnetic resonance imaging of brain tumors.

RATIONALE AND OBJECTIVES: A computerized system that applies the case-based approach to training radiologists to diagnose brain tumors was designed. The authors attempted to provide residents a tool that supports their visual memory and inducts case-based reasoning. METHODS: A relational database with a digital image library was implemented and incorporated into a computer aided instruction environment based on case presentation. An indexing system was structured around case features (case history and radiologic findings). "If-then" type rules were used to control the search direction within the case library and to generate lists of diagnostic hypotheses. The indexing system was evaluated against cases "known" to the system. RESULTS: The current case library consists of 122 cases with 640 digitized images (computed tomography and magnetic resonance imaging). The accuracy of retrieval for "known" to the system cases was 80.7%. CONCLUSIONS: A case library stored on a personal computer can be efficiently searched for a combination of radiologic findings and can offer quality images for comparison to the case in question. A case library is a source of the information that may be used by different teaching applications.

Brain Neoplasms↗
PubMedDate not supplied

Cerebral venous angiomas: MR findings.

Seven patients with suspected cerebral venous angioma studied by either CT or angiography were imaged with magnetic resonance. Six of seven cases demonstrated a stellate appearance on contrast enhanced CT. In two patients this finding was verified by angiography. Flow void was identified on both T1- and T2-weighted pulse sequences. In one patient a field echo sequence demonstrated high intensity signal within the venous angioma. Magnetic resonance proved superior to CT in the identification of these lesions. A stellate configuration with an emanating transcortical vein and centrifugal drainage (transcortical venous flow) from the angioma into a sinus was present in all cases. Centripetal drainage via thalamostriate and internal cerebral veins was not seen. There was no evidence of mass effect, scar, or hemorrhage. Four of the angiomas were located in a frontal lobe and three in a cerebellar hemisphere. This distribution of the lesions is similar to that reported in the literature in which the frontal lobe is the most common location followed by the cerebellar hemisphere. An embryological explanation is cited and supported by a review of the literature.

Adolescent↗
PubMedDate not supplied

Heterogeneity of cerebral cavernous hemangiomas diagnosed by MR imaging.

The cavernous hemangioma (cavernoma) is increasingly recognized as a vascular malformation of the brain that may present with seizures, hemorrhage, or progressive neurological deficit. Since 1985 we have identified 13 cases of presumed cavernoma of the brain based on the findings on CT, selective angiography, and magnetic resonance (MR) imaging. In each case CT showed a high density lesion that was "occult" or "cryptic" on angiography. However, within all lesions MR revealed a complex internal structure consisting of reticulated patches of high and low intensity signal surrounded by a hypointense rim on T1- and T2-weighted pulse sequences. Of the nine operated cases, five resected specimens were compatible with pure arteriovenous malformations (AVMs), and the other four were mixtures of cavernoma with either AVM or venous angioma. Our experience strongly suggests that the above complex of radiographic findings is not at all specific for the cavernoma. We propose that the major common factor shared by such "cavernomatoid" malformations is low blood flow. We believe low flow lesions follow a relatively benign clinical course, and they readily lend themselves to surgical resection.

Adult↗
PubMedDate not supplied

MR artifacts after anterior cervical diskectomy and fusion: a cadaver study.

OBJECTIVE: To identify the source of metallic artifacts observed on cervical spine MR studies following anterior cervical diskectomy and fusion (ACD&F), preoperative and postoperative MR studies were done on cadavers using standard spin echo T1, T2, and GRASS imaging. MATERIALS AND METHODS: An ACD&F was performed on each cadaver at various levels using different combinations of drill burrs, curettes, and suction tips. RESULTS: Results showed that contact between the drill burr and suction tip produced the worst artifacts; however, artifacts still occurred in cases in which the suction tip was not introduced. CONCLUSION: This observation suggests that metal flakes from the curettes also produced artifacts. Image distortion was greater on GRASS imaging than on the spin echo imaging.

Artifacts↗
PubMedDate not supplied

MRI of iatrogenic spinal epidermoid tumor.

A child who had received multiple lumbar punctures 6 years previously was found to have an acquired epidermoid tumor of the lumbar spinal canal, a rare intraspinal lesion. The isointense epidermoid tumor showed ring enhancement only after gadolinium administration.

Child↗
PubMedDate not supplied

Posttraumatic pseudoaneurysm of the posterior meningeal artery associated with intraventricular hemorrhage.

A 22-year-old man sustained a severe head injury and had a torn posterior meningeal artery that caused massive intraventricular hemorrhage. Traumatic pseudoaneurysm of the posterior meningeal artery should be considered in cases where intraventricular hemorrhage occurs in the presence of occipital bone fracture and contiguous epidural hematoma; vertebral angiography is of value in this regard.

Adult↗