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H D Segall

Publications and source records attributed to H D Segall.

17 recordsLinked to original sources
PubMed1992

Cystic fluid in craniopharyngiomas: MR imaging and quantitative analysis.

A prospective study of cystic fluid in craniopharyngiomas in 10 patients was performed to correlate signal intensity on T1-weighted magnetic resonance (MR) images and biochemical analysis. Within 2 days before surgery, each patient underwent MR imaging before and after administration of gadopentetate dimeglumine. Five patients had cystic fluid lower in signal intensity than white matter, with protein levels less than 9,000 mg/dL (90.00 g/L) and no free methemoglobin. One of the five patients had the highest triglyceride concentration (84 mg/dL [0.95 mmol/L]) of all 10 patients; another of these five had the highest cholesterol concentration of all (270 mg/dL [6.98 mmol/L]). It is concluded that the increased signal intensity of cystic fluid in craniopharyngiomas on T1-weighted MR images can be caused by a protein concentration greater than or equal to 9,000 mg/dL (90.00 g/L), the presence of free methemoglobin, or both. In the ranges of concentrations measured in this study, cholesterol and triglyceride did not increase signal intensity.

Adolescent↗
PubMed1992

Magnetic resonance imaging of meningiomas.

MRI with gadolinium enhancement is the imaging modality of choice in the diagnosis of meningiomas. Various MRI features are described. MRI signal intensity characteristics in meningiomas contain information that could be correlated with the histopathology of the tumor. Hyperintensity on T2-weighted images indicates soft tumor consistency and microhypervascularity and is more often seen in aggressive, angioblastic, or meningothelial meningiomas. MRI is useful in demonstrating dural sinus involvement. Meningiomas in unusual locations and their mimics are also presented.

Brain↗
PubMed1991

Neuroradiology.

Explore the source record for details and available documents.

Brain Diseases↗
PubMed1989

Sonography in newborns with cutaneous manifestations of spinal abnormalities.

High-resolution ultrasound is the screening method of choice for neonates with cutaneous signs of underlying spinal pathology. This examination does not require sedation, does not use radiation and is less expensive than computed tomography or magnetic resonance imaging. Ideally, sonograms should be obtained as soon as the cutaneous marker (sacral dimple, hairy patch, skin-covered mass) is found at the newborn examination.

Female↗
PubMed1979

The contrast-enhanced CT scan in the diagnosis of isodense subdural hematoma.

The authors review 29 cases of surgically-proven isodense subdural hematomas examined by non-contrast and contrast-enhanced computerized tomography scans. Three types of isodense collections were noted: homogeneous isodense collections, mixed-density collections, and gravitational layering within subdural collections. Contrast enhancement within the cerebral cortex, cortical vessels, and subdural membranes led to the correct diagnosis in each case. Contrast-enhanced scans are essential for the evaluation of isodense subdural hematomas.

Adult↗
PubMed1979

Use of computerized tomography scanning in supratentorial arachnoid cysts. A report on 20 children and four adults.

Congenital supratentorial arachnoid cysts are large lesions that tend to cause severe distortion and compression of the brain, particularly in infants and children. Diagnosis of such cysts has often been delayed and uncertain in the past, but development of computerized tomography (CT) has greatly improved the ease and accuracy of their identification, helping to provide for earlier surgical treatment and better care of patients. The authors report 24 cases of congenital supratentorial arachnoid cysts, 18 of which were studied with CT scanning; this method proved very valuable in pre- and postoperative assessment in all cases, and far superior to other diagnostic methods.

Adult↗
PubMed1978

Diagnostic and prognostic implications of computed tomography of head trauma.

A total of 210 cases of head trauma were examined using noncontrast enhanced and contrast enhanced computed tomography scans. Evidence of contrast enhancement was seen in 97 cases (46%). Subdural hematoma and focal contusion were the most frequent entities demonstrating contrast enhancement. This finding was also frequently seen in patients with intraventricular hemorrhage (IVH) (5 of 17). Every one of the five patients in this series with IVH whose scans showed enhancement died, whereas out of the 12 whose scans showed no enhancement, five survived. Illustrative cases are presented. The authors feel that contrast enhanced scans are valuable in the evaluation of the full extent of head trauma.

Adolescent↗
PubMed1978

Scintigraphic detection of congenital intracranial vascular malformations.

Nine children with arteriovenous malformations (AVMs), and a tenth with a cerebral aneurysm, had computer-processed dynamic scintigraphy with static scintigrams, transmission computed tomography (CT) both with and without contrast injection, and radiopaque cerebral angiography. All ten lesions were detected by dynamic scintigraphy and angiography, whereas two AVMs were missed on CT scans and the aneurysm and two AVMs (one missed by CT) were not identified on static scintigrams. Time-activity curves generated from regions of interest placed over the cerebral hemispheres, AVMs and/or various venous structures permitted, respectively, estimation of interhemispheric partition of perfusion, estimation of the fraction of total cerebral hemispheric perfusion preferentially directed into a malformation, and indication of the route of venous drainage from the lesions. While dynamic scintigraphy and CT scanning both identified the aneurysm, scintigraphy was the most effective screening test for detecting AVMs owing to its accuracy, lower cost, and lack of required anesthesia, heavy sedation or iodinated contrast agents.

Adolescent↗
PubMedDate not supplied

Cerebral microvascular injury in experimental drug abuse.

An experimental drug abuse research project is reported, in which monkeys and rats were placed on various I.V. amphetamine (Desoxyn) and I.V. barbiturate (Seconal) regimes. The monkeys were studied by serial cerebral angiography. At the end of the study all animals were sacrificed for histological examination. I.V. methamphetamine produced relatively severe cerebral vascular injury and brain damage in most animals. At least part of the damage seemed to be the result of direct vascular injury, arterial and venous. The misuse of Seconal and Ritalin also appeared to be hazardous, but these studies are incomplete, and the degree of hazard has not been fully evaluated.

Animals↗
PubMedDate not supplied

MR imaging of neurocysticercosis.

Magnetic resonance (MR) was performed in 50 patients with neurocysticercosis. Comparison was made with other neuroradiological imaging modalities including CT, myelography, CT ventriculography, and CT myelocisternography. Eighteen patients were found to have intraventricular cysts. In several patients, these were multiple and 22 intraventricular cysts were discovered. Although 4 of the 22 ventricular cysts were missed by MR, T1-weighted images can play a significant role in the early detection of intraventricular cysticercosis cysts, showing the cyst wall (9 of 22), a high intensity mural nodule (6 of 22), and increased signal intensity of the cyst fluid (5 of 22). Cisternal cysts (14 cysts in 10 patients) could be identified; they appear similar to intraventricular cysts, but mural nodules are infrequently seen (1 of 14). Twenty-nine patients had 69 parenchymal cysts. An attempt was made to assess the viability of these parenchymal lesions by matching the CT and MR findings with the Escobar pathologic staging system. Neuroimaging findings seemed compatible with early parenchymal lesions in the vesicular stage in 11 instances. Findings in cases with later stage cysts tend to support the concept that a dying larva provokes pronounced inflammatory reaction in the adjacent brain. Computed tomography remains the superior modality for depicting parenchymal calcifications within dead larvae. A case of a spinal cysticercosis cyst demonstrated with MR (in a patient with extensive intracranial cisternal cysts and a fourth ventricular cyst) is described.

Adolescent↗
PubMedDate not supplied

Lhermitte-Duclos disease: CT and MR findings.

The typical CT findings of Lhermitte-Duclos disease (dysplastic gangliocytoma of the cerebellum) are a hypodense nonenhancing unilateral posterior fossa mass, with or without adjacent occipital thinning, hydrocephalus, and calcification. Magnetic resonance (MR) has been found to be very helpful, and superior to CT, in delineating the margins of the lesion for determining the extent of surgical resection. Since recurrence is known, MR is important in the follow-up of these patients. To our knowledge this is the first reported case that included MR examination with administration of gadolinium. There was no enhancement of the lesion, consistent with previous reports of no contrast enhancement on CT.

Adult↗
PubMedDate not supplied

SPIR MRI in spinal diseases.

We report on our experience with the fat suppression technique of spectral presaturation with inversion recovery MR in imaging certain spinal disorders. This technique may assist in demonstrating or excluding the presence of fat within a lesion (such as lipoma, dermoid, teratoma) or within a normal structure (i.e., vertebral body or epidural space). The method can also be used to suppress normal fat (such as marrow or epidural fat) thus increasing the conspicuity of adjacent high signal intensity lesions seen on T1-weighted images (such as blood and contrast-enhancing tumors or inflammatory lesions).

Abscess↗
PubMedDate not supplied

CT anatomy of the craniovertebral junction in infants and children.

Computed tomographic (GE 9800) images of 129 patients (from newborn to 18 years old) with no evidence of cervical spine pathology were reviewed retrospectively from available material to evaluate normal anatomic appearances in childhood. The synchondroses may appear solid at soft-tissue window settings, while, with appropriate bone-window settings, a lucent line will be seen. Residual lucency and then (generally) sclerosis were seen at synchondroses past the age of classic anatomic fusion. A transversely oriented groove on the undersurfaces of the occipital condyles was imaged in children ages 5-12 years. This groove is described radiologically in that age range for the first time in this report. The development of the ossification centers of C1 was illustrated with CT. The two vertically oriented, rod-shaped ossification centers of the lower dens develop a bilobed appearance in axial section when they begin to fuse. An apparent deficiency of the cortex seen posteriorly in this area (in children as old as 7 years) represents the last remnant of the cleft between the dens centers. The cord was always outlined distinctly by CSF at soft-tissue settings at the foramen magnum and C1 levels without intrathecal or IV contrast enhancement. This anatomic feature is particularly useful since it enables the evaluation of the spinal canal in this region in some cases (especially craniovertebral junction anomalies) without the need for intrathecal contrast materials.

Adolescent↗