Faculty workload: Faculty of medicine Siriraj Hospital.

An analysis of the workload of staff of the Faculty of Medicine Siriraj Hospital, was carried out in line with the Faculty’s policy to improve medical education and for future manpower planning. The results indicate that many clinical faculty members in several departments are overloaded with their clinical responsibilities making it difficult for them to maintain academic objective, while young pre-clinic faculty members do not have to take full responsibility for their duties. Pre-clinic faculty members should therefore increasingly participate in the teaching programme for medical students.

CT findings of seeding tumors.

From 1981 to 1989 there were 43 from 154 cases of metastatic brain tumors, which seeded along the CSF pathways found in the Department of Radiology, Siriraj Hospital Medical School, Bangkok. These seeding tumors were spread from both primary intracranial (25 cases) and extracranial neoplasms (18 cases). Among the primary intracranial tumors, pineal neoplasm was the most frequent site (48%). The next rank was ependymoma (20%), medulloblastoma (16%), glioma (12%) and others (4%). The majority of extracranial neoplasms that seed in the CSF pathways were malignancy of lung (44.4%), choriocarcinoma (22%) and breast (11%). Lateral ventricle was the most frequent site of seeding (65%). The remaining tumors seeded in cisterns, leptomeninge and spinal subarachnoid space. CT is sensitive in detecting seeding tumors but not specific for each type of tumor.

Brainstem germinoma presenting as intermittent apnoea: a rare entity: report of one patient and review of literature.

A 17-year-old man who had repeated pneumonia and presented with intermittent apnoea was described clinically and pathologically. Neurological examination and computed axial tomography revealed a calcified mass over the lower brainstem. Neurological intervention was done with removal of the tumour and the pathological section showed the classical picture of germinoma. The patient was given irradiation treatment afterwards and he was weaned off the respirator within a week. Unfortunately, he died because of recurrent chest infection after a long hospital admission of 92 days. Reviewing the literature showed the rarity of the germinoma at the brainstem location.

Computed tomography of intraventricular masses.

The CT appearances in 87 patients with intraventricular mass lesion were analyzed in order to verify the characteristic finding. The pathological diagnoses included medulloblastoma in 27, astrocytoma in 16, craniopharyngioma in 15, ependymoma in 9, meningioma in 7, AVM in 4, choroid plexus papilloma and epidermoid cyst in 2 each. One each had teratoma, ependymal cyst, cysticercosis, cavernous hemangioma and hemangioblastoma. The histologic diagnosis could be suggested by the frequency, location, density, age and sex of the patients. The differential features of each diagnosis are discussed.

CT diagnosis of cerebral cysticercosis.

CT findings of 132 patients with cerebral cysticercosis were analysed. The most common finding was multiple parenchymal punctate calcifications, accounting for 53 per cent; calcifications mostly scattered in both cerebral hemispheres. The second most common finding was enhancing ring(s) or nodule(s) of about 1 cm in diameter with perifocal edema, about 43 per cent. Other findings included thin-walled parenchymal cysts of various sizes from less than 1 cm to 7 cm in diameter, non-enhancing low-density area, intraventricular and cisternal cysts, and hydrocephalus due to obstruction of cerebrospinal fluid pathway by the cyst, arachnoiditis, or ependymitis. About 30 per cent of patients had a combination of these forms of cysticercosis. Seizure disorder was the most common presenting symptom. Praziquantel was used effectively in parenchymal cystic forms but without response in intraventricular and cisternal cysts. In conclusion, CT is considered to be the procedure of choice for the detection of cerebral cysticercosis and the follow-up of patients after medical or surgical treatment. When multiple forms of cysticercosis are present, the diagnosis can usually be made with accuracy. A single finding of non-specific pattern such as enhancing ring or nodule, low-density area, or parenchymal cyst(s) without typical mural nodules, has to be differentiated from other conditions such as tumors and inflammatory process. Clinical correlation and follow-up scan are required in these cases in which the definitive diagnosis cannot be ascertained, and in certain cases, surgical intervention may be necessary.

Computed tomography in the diagnosis of central nervous system lymphomas.

CT appearances of 13 patients diagnosed as having CNS lymphoma were reviewed. Eight patients were of primary type and 5 patients had secondary CNS involvement. In primary CNS lymphoma, the median age was 62.5 years. All except one were male. Solitary lesions were observed in 4 patients; multiple lesions in 3 patients and an infiltrative lesion in one. Characteristic CT finding was a hyper-or isodense mass with homogeneous enhancement in the gray matter and corpus callosum. In secondary CNS lymphoma, the median age was 30 years. Two had solitary lesions. Isodense lesions were found in 4 of 5 patients.

CT findings of brain metastases.

In 121 proven cases of intracranial metastases, lung cancer was as high as 48 per cent. Multiple lesions were noted (67.8%) in almost every type of organ source. Brain parenchyma (80.3%), predominantly supratentorium was the major site of metastases. The minority was observed in leptomeninge, cranial bone and subgaleal tissue. Subarachnoid seeding tumors along CSF pathways spread mainly from pineal neoplasms; a few cases from lung and choriocarcinoma. Extensive brain edema occurred in metastases from almost every type of primary organ source. Calcification exhibited 5.8 per cent and their origins were lung and breast. Bleeding tumors were noted in 10.7 per cent mainly from choriocarcinoma, a few from lung and GI. Hyperdense tumors occurred in 86.8 per cent on noncontrast scans. Almost all tumors (95.2%) showed contrast enhancement, predominantly ring-shaped lesions. Their organ sources were GI, lung and breast. A few patterns of enhancement were homogeneous and heterogeneous. Non-enhanced lesion were noted in 4.8 per cent mainly due to the high density of calcium and blood inside the tumors. Apart from seeding, calcified and bleeding tumors, the CT findings were not specific for various types of metastases.