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A C Mamourian

Publications and source records attributed to A C Mamourian.

At least 37 records · Page 2Linked to original sources
PubMed1995

Glutaric aciduria: improved MR appearance after aggressive therapy.

Advances in understanding the metabolic abnormalities which cause glutaric aciduria allow biochemical diagnosis on the basis of deficient enzyme and the potential for therapy. Brain abnormalities associated with this inborn error of metabolism have been demonstrated with CT and MR. The findings typically described are atrophy of the fronto-temporal regions with large insular cisterns and diffuse white matter hypodensities. We present a patient with glutaric aciduria, confirmed by enzymatic assay, who had these findings on CT and MR examination. Repeat imaging demonstrated significant improvement after dietary therapy and aggressive prevention of catabolism during febrile illness.

Amino Acid Metabolism, Inborn Errors↗
PubMed1995

MR of giant arachnoid granulation, a normal variant presenting as a mass within the dural venous sinus.

We report three cases of masses within the cerebral dural venous sinuses shown with either MR or angiography. The dural venous sinuses of 10 patients without known venous disease were examined at autopsy. In two patients, three giant arachnoid granulations were identified. On the basis of the literature and our limited autopsy series, we suggest that these lesions identified at imaging are giant arachnoid granulations, normal variants of no known clinical significance.

Adult↗
PubMed1995

The asymmetric mamillary body: association with medial temporal lobe disease demonstrated with MR.

PURPOSE: To determine whether mamillary body atrophy is caused by deafferentation of the mamillary body in patients with mesial temporal sclerosis. METHODS: We studied 36 patients with thin-section MR to assess mamillary body symmetry. These patients included 10 control subjects without seizures and 26 patients with a history of seizures. Thin-section T1 scans were available for all cases. The patients with epilepsy underwent axial and coronal T2 scans as well. RESULTS: In five of eight cases with prior medial temporal lobe resection for intractable epilepsy, there was evidence of unilateral mamillary body atrophy ipsilateral to the resection. Similar findings were evident in three of six patients with MR findings of mesial temporal sclerosis without surgery. Two patients with medial temporal stroke or tumor also had ipsilateral mamillary body atrophy. CONCLUSION: These findings provide support for the proposed mechanism of mamillary body atrophy caused by prior medial temporal lobe injury.

Adult↗
PubMed1994

Dystonia, hyperintense basal ganglia, and high whole blood manganese levels in Alagille's syndrome.

Hyperintensity of the globus pallidus on T1-weighted magnetic resonance imaging (MRI) has been reported in patients with chronic liver disease. This abnormality has been associated with the severity of liver disease and tremor, but its cause is unknown. Similar MRI signal abnormalities have been reported in experimental models of manganese neurotoxicity. This case report describes a child with Alagille's syndrome and end-stage liver disease who developed dystonia and tremor associated with an elevated whole blood manganese level and symmetric hyperintense globus pallidi and subthalamic nuclei on T1-weighted but not T2-weighted MRI. Liver transplantation was performed; 2 months later, neurological function was improved, manganese levels were normal, and the MRI signal abnormality had completely resolved. This child had neurological findings described in manganese neurotoxicity with compatible laboratory and radiological findings. Manganese is excreted by the liver in bile, and toxicity may have resulted from the inadequacy of this mechanism, subsequently corrected by liver transplantation.

Alagille Syndrome↗
PubMed1994

Symptomatic manganese neurotoxicity in a patient with chronic liver disease: correlation of clinical symptoms with MRI findings.

Hyperintense symmetric pallidal lesions have been described in chronic hepatic failure. Similar lesions are reported in experimental models of manganese neurotoxicity. We describe an 8-year-old girl with chronic hepatic failure and dystonia in association with an elevated whole blood manganese level and symmetric hyperintense pallidal lesions on magnetic resonance imaging. After hepatic transplantation, her symptoms and signs resolved with normalization of magnetic resonance imaging and the whole blood manganese suggesting that in chronic hepatic failure, the pallidal lesions may be secondary to manganese deposition.

Alagille Syndrome↗
PubMed1994

Long-term MRI changes in brain after pediatric open heart surgery.

We performed magnetic resonance imaging (MRI) on the brain and neurologic examinations on 23 children after open heart surgery for congenital heart disease. Twenty children also had psychometric assessments. Examinations were performed at a mean age of 66 months (range, 26 to 180 months). Age at operation was less than 1 month in 43% and more than 6 months in 45%. Abnormal scans were found in 17 (74%) and showed diffuse findings consistent with hypoxic-ischemic encephalopathy, with or without areas of cortical infarction; focal cortical infarction alone; and (in one patient) callosal agenesis and abnormal neuronal migration. Normal IQ and neurologic examinations were found in all six of those who had a normal MRI, and five of six children with changes consistent with focal cortical infarction without diffuse change had a normal neurologic examination. Cerebral palsy and mental retardation was common in the group with diffuse abnormality (in eight of nine children), and this was more likely to occur in those who underwent prolonged (> 45 minutes) hypothermic circulatory arrest and operation during early infancy (P = .004). Focal cortical findings without diffuse changes were more likely in those who underwent open heart surgery without hypothermic circulatory arrest and were older than 6 months at operation, and these children were less likely to have frank neurodevelopmental sequelae. Thus, in our population, focal cortical lesions were common after open heart surgery, and, in addition, diffuse brain abnormality on MRI plus neurologic sequelae were common after prolonged hypothermic circulatory arrest.

Adolescent↗
PubMed1994

Neonatal pontomedullary disconnection with aplasia or destruction of the lower brain stem: a case of pontoneocerebellar hypoplasia?

We report a neonate who presented with marked hypotonia and absent suck reflex. MR demonstrated complete absence of the pons as well as absence of a basilar artery flow void. Our case exhibits features similar to those described in previous reports of pontoneocerebellar hypoplasia, but with a more severe degree of pontine involvement. The associated vascular findings suggest a vascular insult to the brain stem as the cause.

Basilar Artery↗
PubMed1993

Handgun control.

Explore the source record for details and available documents.

Firearms↗
PubMed1991

Urea cycle defect: a case with MR and CT findings resembling infarct.

A 2 1/2 year old girl was admitted to the hospital because of recurrent vomitting, impaired consciousness, and hyperammonemia. MR and CT findings resembled an infarct, but she was found to have a defect in the urea cycle, partial ornithine transcarbamylase deficiency.

Amino Acid Metabolism, Inborn Errors↗
PubMed1989

Pelvic fibromatosis: case report and review of literature.

The case report of a patient with pelvic fibromatosis is described. Excision of the tumor without sacrificing organs or major vessels was performed. Although not malignant, this tumor can be life-threatening due to its locally invasive properties. A variety of therapeutic options are discussed.

Adult↗
PubMed1988

Magnetic resonance imaging in pituitary apoplexy.

The diagnosis of pituitary apoplexy, an often-fatal disorder, is frequently delayed. Computed tomographic (CT) scanning has been shown to be useful in the detection of pituitary apoplexy; however, the value of magnetic resonance imaging (MRI) is yet to be determined. The MRI and CT scans of three consecutive and histopathologically proved cases of pituitary apoplexy were reviewed. The MRI scans obtained at least five days after the onset of symptoms suggested pituitary apoplexy (hemorrhage) in all three cases, while CT scanning indicated pituitary hemorrhage in only one case. Increased signal on the T1-weighted image was the hallmark on MRI scans in all three cases. These findings suggest that MRI scanning may be superior to CT scanning in identifying pituitary apoplexy, at least in the subacute phase.

Adult↗