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Biomedical subjects

H D Segall

Publications and source records attributed to H D Segall.

At least 37 records · Page 2Linked to original sources

Intraspinal seeding from intracranial tumors in children.

Cerebrospinal fluid-borne metastases were demonstrated by metrizamide myelography in 20 children with primary intracranial tumors, posterior fossa medulloblastomas being the most common. The lumbosacral region was affected most often, with nerve root thickening, nodularity, and irregularity of the thecal sac. Cord cloaking, nodularity, and meningeal disease were common in the cervical and thoracic areas. Intraspinal spread from primary intracranial tumors signals a poor prognosis. However, the early detection of intraspinal spread afforded by metrizamide myelography can alter therapy and thereby improve prognosis.

Brain Neoplasms↗

Evaluation of cerebrospinal fluid rhinorrhea by metrizamide computed tomographic cisternography.

Seven interesting and instructive cases of cerebrospinal fluid rhinorrhea evaluated by metrizamide computed tomographic cisternography are presented. The rhinorrhea was spontaneous in three patients and was related to previous head trauma or surgical procedures in four patients. The anatomical site and the extent of the fistula were demonstrated precisely by directly showing metrizamide passing through the bony defect. A combination of bone dehiscence and metrizamide within the adjacent paranasal sinuses or the nasal cavity is also useful in localization. Distortion of the interhemispheric fissure, sylvian fissure, or basal sulci indicates the probability of brain herniation through the defect.

Adolescent↗

Syringohydromyelia following meningomyelocele surgery--role of metrizamide myelography and computed tomography.

Five children developed symptoms attributable to syringohydromyelia several years following neonatal surgery for lumbosacral meningomyelocele. Metrizamide injection followed by computed tomography (CT) was performed in all five patients. In two patients, there was direct opacification of both the subarachnoid space and the syringohydromyelia. In a further two patients, delayed CT demonstrated late opacification of the central cavity from contrast introduced into the subarachnoid space. In the fifth patient via a suboccipital puncture, there was fortuitous filling of a caudally displaced fourth ventricle communicating with a central cavity within the cord, but there was no visualization of the subarachnoid space. Surgery with decompression and plugging of the obex halted the progression of the disease in all the patients.

Adolescent↗

Computed tomography of posterior fossa ependymomas in childhood.

In reviewing 10 children with surgically proven posterior fossa ependymomas, various computed tomographic representations were seen. Calcification, seen in 50% of the cases, was the single most important finding suggesting the diagnosis of ependymoma. The appearance of two of our ependymomas mimicked the "typical" appearance of medulloblastomas. A case of calcified brainstem ependymoma is presented, to our knowledge, the first such case studied with computed tomography.

Adolescent↗

Intracranial metastatic Wilms' tumor in children: a report of two cases.

Two cases are presented of children with intracranial metastasis from Wilms' tumor. Both patients had undergone nephrectomies for Wilms' tumor, one 19 months and the other 32 months prior to clinical presentation of intracranial metastasis. Computed tomographic examination in both cases demonstrated lesions that did not have any particularly unique features. Subsequent craniotomy and removal of the tumor in one case confirmed metastatic intracranial Wilms' tumor.

Brain Neoplasms↗

Combined computed tomographic and radionuclide imaging in the long-term follow-up of children with primary intra-axial intracranial neoplasms.

Radionuclide and computed tomographic (CT) scanning was performed for the long-term follow-up of 63 patients who had been treated for primary intracranial central nervous system tumors. This group included 23 children with supratentorial lesions and 40 with infratentorial lesions. The results of imaging were correlated with clinical assessment and the results of cytologic evaluation of the cerebrospinal fluid and, when available, surgical or autopsy findings. The sensitivity, specificity, and positive predictive value of both CT and radionuclide scanning were evaluated for each type of tumor. These two modalities play a complementary role in the long-term follow-up of children with primary intra-axial neoplasms.

Adolescent↗

Management of hydrocephalus secondary to intraventricular hemorrhage in the preterm infant with a subcutaneous ventricular catheter reservoir.

To control hydrocephalus resulting from massive intraventricular hemorrhage in premature neonates with respiratory distress syndrome, we inserted a specially designed low profile subcutaneous ventricular catheter reservoir (reservoir) by the 12th day of life (average; range, 3 to 30 days) in 20 neonates whose mean birth weight was 1110 +/- 270 g (28.7 +/- 1.6 weeks of gestation). The reservoir was repeatedly aspirated over 10 to 48 days. No cerebrospinal fluid infection, reservoir obstruction, or breakdown of the skin overlying the reservoir occurred. Serial computed tomographic scans documented control of the hydrocephalus and an increase in the thickness of the cortical mantle of the survivors. No mortality was associated with placement of the reservoir or its subsequent conversion, if necessary, to a ventriculoperitoneal shunt. However, only 7 of the 20 infants survived. On follow-up 3 to 5 years later, 2 of the 7 have normal intellectual and motor development. Two infants are normal intellectually, but have a motor deficit. The remaining 3 patients have both significant intellectual and motor developmental delay. The use of the reservoir is offered as a safe and effective alternative to repeated ventricular punctures, external ventricular drainage, or initial shunting. Aggressive management of hydrocephalus secondary to intraventricular hemorrhage may improve neurological function in some surviving neonates.

Brain↗

Assessment of cerebral perfusion in childhood strokes.

Thirty-three children who had strokes were studied by dynamic and static scintigraphy, 29 by CT scanning, and 10 by cerebral angiography. The accuracy of dynamic scintigraphy in stroke detection during the first week of clinical symptoms was 94% while CT scanning was 60% accurate and static scintigraphy 11% accurate. During the second week the accuracy of CT scanning increased to 100%, but static scintigraphy improved to only 50%. Fifty percent of scintiangiograms performed during the first week showed either luxuriant perfusion or flip-flop patterns. In some patients these two flow patterns changed to that of cerebral hemispheric ischemia after going through a phase during which perfusion appeared to be equal in the two hemispheres. Dynamic scintigraphy is believed to be the test of choice for stroke detection in children during the first week.

Adolescent↗

Computed tomographic observations pertinent to intracranial venous thrombotic and occlusive disease in childhood. State of the art, some new data, and hypotheses.

Selected topics are discussed and new observations recorded regarding computed tomographic (CT) evaluation of intracranial venous thrombotic and occlusive disease in childhood. High density of the vein of Galen and adjacent venous sinuses (relative to brain) can be seen normally in children. A number of potential pitfalls in the diagnosis of superior sagittal sinus thrombosis are also disclosed. A case of cavernous sinus thrombosis with abnormal CT changes in included. In addition, the normal CT appearance of the cavernous sinus is described. In some cases, filling defects occur which appear to correlate with normal cranial nerves. An unusual case of venous sinus occlusion by neoplasm (sarcoma) is presented. Finally, new findings in the Sturge-Weber syndrome are analyzed. Enhancement of the brain in this condition may have its basis in altered circulation resulting from fundamental venous abnormalities.

Adolescent↗

Inconsistent venous opacification: a pitfall of epidural venography.

The lumbar epidural venograms of 45 consecutive patients with prior normal or equivocal myelographic examinations were reviewed. Each venographic injection was performed using transfemoral double-catheter technique, abdominal compression, Valsalva maneuver, and serial filming for 12 sec. There was a 30% incidence of false "occlusions" of epidural veins suggestive of compression by a herniated intervertebral disk. These false venous occlusions were demonstrated to be such by both subsequent opacification of previously nonopacified veins and lack of opacification of previously opacified veins during repeat venography. In view of the significant incidence of spurious venous occlusions in this series, It is recommended that epidural venography with single injection should be interpreted with caution except for normal studies.

Catheterization↗

Lipomas of the corpus callosum associated with frontal dysraphism.

Using computed tomography (CT), we have been able to identify the combined occurrence of lipoma of the corpus callosum and dysraphic lesions associated with frontal bone defects in two cases. In one case, there was a true encephalocele, and in the other case a lipoma with cartilaginous tissue was present. Such combinations are very rare; thus, the impetus to report these cases. The disorganization of the central nervous system was extensive in the first infant and was associated with profound developmental delay, while the second infant had much less anatomical abnormality, and development to date is normal. Bony defects (on skull films), typical appearances of lipoma of the corpus callosum, and characteristics of the dysraphic lesions (on CT) were seen. Angiography was obtained in the infant with a true encephalocele.

Abnormalities, Multiple↗

Computed tomography of posterior fossa trauma.

A group of 1,700 cases of head trauma were reviewed to determine the incidence of posterior fossa injuries and to assess the value of computed tomography (CT) in their diagnosis and management. In 57 cases (3.3%), the most significant and primary injuries were within the posterior fossa. These included epidural hematoma (EDH), acute and chronic subdural hematoma (SDH), and parenchymal hemorrhage and contusion of the cerebellum and brainstem. The prognosis varies with the location and severity of the injury. Brainstem injuries are associated with a high mortality rate. Computed tomography proves particularly useful in the early recognition of brainstem injury. The demonstration by CT of obliteration of the cisterns surrounding the brainstem is a reliable sign of a grave prognosis in brainstem injury. Contrast enhancement is useful in demonstrating whether the dural sinuses are displaced, thus differentiating EDH from SDH. Except in the rare case of vascular injury unassociated with EDH, CT correlated with the neurological examination is an accurate method of determining the nature, location, and extent of significant posterior fossa injury. Scans of high quality are mandatory, and frequent supplementary contrast studies are recommended.

Adolescent↗

Radiological investigation of sellar region masses in children.

The treatment and prognosis of sellar region masses in children differ according to the type of tumor, and thus accurate determination of the extent and characteristics of the lesion is important. Evaluation by conventional skull radiography, complex-motion tomography, radionuclide imaging, computed tomography, cerebral air studies, and cerebral angiography has demonstrated definable characteristics of the various types of tumors and often allows distinction from benign processes.

Adolescent↗