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H D Segall

Publications and source records attributed to H D Segall.

85 records · Page 5Linked to original sources

MRI of intraventricular cysticercosis: surgical implications.

OBJECTIVE: Our goal was to evaluate the role of Gd-enhanced MR in the diagnosis and surgical planning of intraventricular cysticercosis cysts. MATERIALS AND METHODS: Thirty-three patients with intraventricular cysticercosis were evaluated with Gd-enhanced MRI including follow-up studies ranging over time periods from 6 months to 8 years. The patient age ranged from 17 to 65 years. All had lived in Mexico or Central America. RESULTS: Twenty patients had surgical removal of the cysts. The majority of patients (18 of 20) who had surgical removal of the cyst showed improvement with resolution of hydrocephalus. Two of 20 patients required additional shunting to alleviate hydrocephalus. In these two patients, Gd-enhanced MR showed cyst wall enhancement. Ependymitis with adhesion was found at surgery in these two patients. Nine patients had shunt placement; one of nine patients showed cyst enlargement 2.5 years later that required surgical removal. Of the remaining eight patients, four showed irregular, thick, ring-like enhancement mimicking a neoplasm on follow-up imaging studies. Four patients with cysts in the lateral ventricle did not require treatment. Two of the four patients showed irregular, thick, ring-like enhancement on follow-up imaging studies. CONCLUSION: Gadolinium-enhanced MR is more sensitive than contrast-enhanced CT for detecting ependymitis, which is essential in deciding whether surgical removal of the cyst or shunt placement is indicated. A degenerating intraventricular cysticercosis cyst may present as an irregular, thick, ring-like enhancing lesion or a nodular enhancing lesion with varying degrees of surrounding edema, mimicking a neoplasm.

Adolescent↗

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↗

Early CT detection of intracranial seeding from medulloblastoma.

Since 1975, intracranial subarachnoid metastases of medulloblastoma have been detected in seven of 23 initial contrast-enhanced computed tomographic (CT) scans in children with proven medulloblastoma. Furthermore, four of the seven cases with subarachnoid seeding were diagnosed after the introduction of high-resolution contrast-enhanced CT. Only three cases of seeding had been detected in the previous 17 low-resolution cases studied with CT. Thus, it is quite likely that the incidence of subarachnoid metastases may be substantially more than the overall figure of 30% indicated by this series. This may have an impact on the treatment of these patients, since the frequent appearance of metastases may indicate the need for more vigorous chemotherapeutic regimens. One should be aware of the possibility of early intracranial subarachnoid seeding and that it can be demonstrated by contrast-enhanced CT. This is particularly true when using high-resolution scanners in conjunction with 5 mm sections through the posterior fossa.

Adolescent↗

CT patterns in histopathologically complex cavernous hemangiomas.

Computed tomographic (CT) studies were correlated with microscopic findings in 10 histologically verified cavernous hemangiomas in nine patients. In four of the 10 lesions, two or more distinct types of cerebrovascular malformations were identified histopathologically. These included arteriovenous malformations, venous malformations, and telangiectasis. Such coexistence of various types of cerebrovascular malformations has been reported rarely. In each of the four combined lesions, there was evidence of recent or old hemorrhage. The CT findings were nonspecific and were similar to those seen in a variety of intracranial pathologic conditions.

Adult↗

CT observations pertinent to septic cavernous sinus thrombosis.

The use of high-resolution computed tomography (CT) is described in four patients with septic cavernous sinus thrombosis. In all patients CT findings included multiple irregular filling defects in the enhancing cavernous sinus. Unilateral or bilateral inflammatory changes in the orbital soft tissues were also present. Enlargement of the superior ophthalmic vein due to extension of thrombophlebitis was noted in three patients.

Aged↗

Computed tomography of carotid-cavernous fistula.

Fourteen patients with angiographically-proven carotid-cavernous fistulas were evaluated by computed tomography (CT). Unilateral or bilateral exophthalmos was noted in 12 patients. Slight blurring of the margin of the globe was present in two, presumably due to pulsations of the globe or conjunctival edema. Superior ophthalmic veins were prominent in 12 patients and were often larger on the side of the fistula. Irregularity or absence of contrast enhancement of the superior ophthalmic vein may indicate partial or complete thrombosis. Focal bulging or diffuse distention of the cavernous sinus was noted in nine patients. Enlargement of the extraocular muscles was observed in seven with swelling of the eyelids and edema of the conjunctiva in eight patients. The pattern of venous drainage, type of fistula, and time intervals between trauma, commencement of fistula, and CT scan may affect the CT manifestations of carotid-cavernous fistulas.

Adult↗

Intraventricular cysticercal cysts: further neuroradiologic observations and neurosurgical implications.

Intraventricular cysticercosis is potentially lethal. Six of 46 patients died from acute hydrocephalus shortly after hospital admission. The need for early computed tomographic scanning in immigrants from endemic areas complaining of headaches is emphasized by this experience. If time has elapsed since the initial diagnosis, these cysts may migrate within the ventricular system. Reconfirmation of the location of an intraventricular cysticercal cyst is advisable before surgery. Contrast enhancement of an intraventricular cysticercal cyst implies associated granular ependymitis. Surgical removal of such cysts probably should not be attempted as long as the cysts are not causing significant mass effect with neurologic signs and symptoms. Shunting alone is advocated for the treatment of hydrocephalus.

Adolescent↗

Computed tomography in acute posterior fossa infarcts.

Thirty-one cases of acute posterior fossa infarcts are reported. CT evidence of obliterated posterior fossa cisterns and hydrocephalus indicates a grave prognosis due to brainstem compression. Progressive obliteration of posterior fossa cisterns may be used as an indicator for surgical decompression. Patients with intact posterior fossa cisterns had good recoveries without surgical treatment. CT can be used to diagnose the very early phase of an acute posterior fossa infarct and has prognostic value in predicting the outcome.

Adult↗