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R S Pinto

Publications and source records attributed to R S Pinto.

At least 55 records · Page 3Linked to original sources
PubMed1977

The base view in vertebral angiography. An aid in the diagnosis of extraaxial cerebellopontine angle tumors.

Though the advent of computed tomography has improved the detection of posterior fossa lesions, there are times when it can not be used to differentiate between an intra- and extraaxial lesion, particularly when the mass is anteriorly located. Base view angiography can be used to make this distinction, accurately localize the lesion, and demonstrate involvement or compression of vital adjoining structures.

Cerebellar Neoplasms↗
PubMed1976

Evaluation of sellar and parasellar masses by computed tomography.

Computed tomography is the method of choice for initial evaluation of patients with potential suprasellar masses. In our experience, CT has proved completely reliable for detecting or ruling out the presence of a suprasellar mass, the direction and degree of parasellar extension, and the presence of any calcific or cystic component of the lesion. When multiple cut CT has been negative, further diagnostic studies have proved unrewarding. When CT has been positive, additional studies have been required in some cases to rule out aneurysm prior to craniotomy.

Adenoma↗
PubMed1976

Chordoma: radiologic evaluation of 20 cases.

Experience with 20 cases of chordoma is summarized. Three of four intracranial tumors presented as sellar tumors. The clivus remained intact for 2, 3 1/2, and 4 years, respectively, in three patients despite extensive destructive lesions of the sellar region. Our data and those of others indicate that approximately half the patients with chordomas have erosion of the clivus at the time of initial medical evaluation. The other half mainly have sellar destructive lesions with or without associated clival erosion. Calcification occurs in 50%-70% of intracranial chordomas. A nasopharyngeal mass is present in one-third. Vertebral chordomas often involve two or more vertebrae, producing destructive lesions which often have a sclerotic rim. The intervertebral discs are commonly affected. A paraspinal soft tissue mass, half the time containing calcification, is often present. Sacral lesions are characterized by a midline destructive lesion, occasionally associated with expansion, with or without osteosclerosis. A firm, fixed, extrarectal, presacral mass which may contain calcification or fragments of bone is almost always present.

Adult↗
PubMed1975

The osseous and angiographic features of vertebral chordomas.

Eight cases of vertebral chordoma, exclusive of the sacrococcygeus, are presented. The conventional radiographic signs in descending order of importance in differential diagnosis are: destruction of multiple adjacent vertebral bodies; a paravertebral or precervical soft tissue mass; osteosclerosis, seen mainly at the periphery of the destructive lesion; and involvement of the intervening intervertebral disc space. All eight patients had a demonstrable intraspinal extension of chordoma on myelography. Four patients had complete blocks, two epidural in configuration, and two intradural in appearance - indicative of dural invasion by the neoplasm. Four patients had angiographic evaluation. Two demonstrated angiographic features usually associated with soft tissue malignant tumors. Angiography in all four cases was helpful in determining the full extent of the lesion, more so than either conventional radiography or myelography.

Adult↗
PubMed1975

Radiologic features of benign pleomorphic adenoma of the hard palate.

The clinical and radiographic features of two cases of pleomorphic adenoma are discussed. With the use of hypocycloidal tomography, definitive radiographic signs of benignity are demonstrated. They include (1) a radiolucent defect with well-defined cortical margins; (2) beveled margins which describe an intraoral origin of the neoplasm; (3) confinement of the neoplasm within the actual osseous defect, or within the projected circumferential diameter of the defect, if complete erosion has occurred; and (4) lack of periosteal reaction or osseous involvement of the hard palate adjacent to the radiolucent defect.

Adenoma, Pleomorphic↗
PubMed1975

Myelographic cervical nerve root deformities.

Myelograms of nerve roots and adjacent subarachnoid space were reviewed to characterize 231 cervical root deformities from both symptomatic and asymptomatic patients. Good correlation between specific features of root deformities and clinical significance could not be demonstrated. Some features were slightly suggestive of clinical significance but occurred in a sufficient number of asymptomatic patients to make them unreliable. The most accurate determinants of root deformity significance are clincal and electromyographic findings.

Adult↗
PubMed1975

Neuroradiology of basal anterior fossa (transethmoidal) encephaloceles.

Encephaloceles of the basal anterior fossa, though primarily congenital in origin, may be insidious in presentation and remain undetected until adulthood. Conventional plain films and hypocycloidal tomograms show a basal osseous defect with its margins bevelled toward the nasopharynx. Magnification angiography is the diagnostic study of choice and reveals herniation of the anterior inferior frontal artery through the osseous defect. Pneumoencephalography, the classical technique of investigation, was found to be unrewarding in demonstrating the herniated sac or in determining the presence or absence of brain tissue within the sac; however, it is of value in demonstrating a ventricular communication with the encephalocele and evaluating ventricular dilatation.

Cerebral Angiography↗
PubMedDate not supplied

Diagnosis of carotid artery stenosis: comparison of 2DFT time-of-flight MR angiography with contrast angiography in 50 patients.

Fifty patients underwent 2DFT time-of-flight MR angiography and intraarterial contrast angiography for evaluation of possible carotid atherosclerotic disease. The MR angiography technique employed contiguous axial flow-sensitive (short TR/TE) slices that were reformatted and postprocessed by using a maximum-intensity projection algorithm to provide 16 angiographic views of the carotid arteries. Both studies were independently reviewed by two observers in a blinded manner. Carotid arteries were categorized as normal, mildly stenotic, moderately stenotic, severely stenotic, or occluded. For the 94 carotid arteries available for review, one observer reported a 70% agreement between the two techniques and the second observer reported a 56% agreement (p = .0001). The best correlation was in the severely stenotic category and the worst was in the occluded category. Agreement between observers was 67% for MR angiography and 72% for contrast angiography, which was similar to that between the two techniques. Although not all carotid atherosclerotic disease was visualized equally well, 2DFT time-of-flight MR angiography had a good overall correlation with the "gold standard" of intraarterial contrast angiography, supporting its use as a screening technique. While further improvements are needed, use of MR angiography as the primary diagnostic tool for many patients with suspected carotid stenosis should continue to increase.

Aged↗
PubMedDate not supplied

Thrombogenicity of Teflon versus copolymer-coated guidewires: evaluation with scanning electron microscopy.

Utilizing the scanning electron microscope, we compared a new guidewire with copolymer coating with standard Teflon-coated, coiled-spring guidewires in both clinical and in vitro settings. Intense thrombogenicity was observed with the Teflon-coated guidewires with formed thrombi ranging in size from 50-100 microns. No formed thrombus was noted on any of the specimens of the copolymer guidewire, although isolated clumps of platelets and erythrocytes without fibrin strands were seen infrequently. We conclude that the copolymer guidewire is markedly less thrombogenic than Teflon-coated guidewires.

Cerebral Angiography↗
PubMedDate not supplied

Computed tomographic changes of hypertensive encephalopathy.

Computed tomographic (CT) scans were evaluated in 11 patients with acute hypertensive encephalopathy. Hypertensive encephalopathy is characterized by an acute, severe rise in blood pressure associated with headache, nausea, vomiting, altered mental status, and focal neurologic deficits, and rapid improvement after control of blood pressure. The systolic blood pressure range is 200-280 mm Hg; diastolic is 130-170 mm Hg. The most common CT finding was white-matter edema, diffuse or focal, affecting the supratentorial compartment in all cases and the infratentorial compartment in eight. These changes resolved after the blood pressure was lowered in all six patients studied by follow-up CT. Permanent areas of infarction were demonstrated in three patients. These abnormalities are correlated with the neuropathologic findings in hypertensive encephalopathy.

Adolescent↗
PubMedDate not supplied

Vasospasm secondary to ruptured aneurysm: assessment by digital intravenous angiography.

Digital intravenous angiography was used for the documentation and evaluation of cerebral vasospasm secondary to acute ruptured aneurysm. Attenuation of vessel caliber and/or generalized poor visualization of intracranial arteries and prolongation of circulation time were observed in seven patients with the acute clinical diagnosis of cerebral vasospasm. Posttreatment intravenous angiography demonstrated improvement in both arterial caliber and circulation time in six patients who responded to medical therapy for vasospasm. Digital intravenous angiography allowed repeat investigations of the intracranial vasculature safely and quickly without undue risk to the critically ill patient.

Cerebral Angiography↗
PubMedDate not supplied

Comparison of radiographic quality and adverse reactions in myelography with iopamidol and metrizamide.

A randomized double-blind study was conducted to compare the radiographic quality and adverse reactions in myelography of the two nonionic water-soluble contrast media, iopamidol and metrizamide. A total of 46 myelograms were obtained, 28 with iopamidol and 18 with metrizamide. Untoward reactions consisted of nausea, headaches, back and leg pain, neuropsychiatric findings, and urinary retention. Iopamidol caused no reactions in 20 of the 28 cases, while metrizamide caused no reactions in only three of 18 cases. Film quality evaluation showed 22 of the 28 studies with iopamidol were judged excellent, whereas only 11 of the 18 metrizamide studies were judged excellent. The results of this study suggest that iopamidol produces better quality studies with fewer and milder adverse reactions than metrizamide.

Adult↗
PubMedDate not supplied

Neuroradiologic diagnosis of subdural empyema and CT limitations.

Five cases of subdural empyema are described. Two of the cases eluded a definitive computed tomography (CT) diagnosis despite classical clinical background. Extracerebral collection with definitive border enhancement was seen in the other three cases. Mass effect, present in all five cases, was related to the extracerebral collection in three cases and diffuse cerebral edema and/or infarction in two. Angiography in four cases initially demonstrated an extracerebral collection in three and inflammatory angiospasm in two. Repeat angiography demonstrated an extracerebral collection in the fourth case. In the proper clinical setting subdural empyema should be considered even in the absence of an extracerebral collection when mass effect or an infarction pattern is seen on CT. Angiography may be diagnostic in such cases. Hopefully, newer techniques will further the diagnostic efficacy of CT in this disease.

Adolescent↗