John C. Harbert

Large Arachnoid Cysts at the Cranial Base

Two infants who presented with macrocephaly had very large noncommunicating cysts at the cranial base that were displacing the brain. Only one of the patients was hydrocephalic; he eventually underwent ventriculoperitoneal shunting after craniotomy and attempted internal drainage of the cyst. The other infant had a cystoperitoneal shunt. Both have done well after 4 and 6 years of follow-up, respectively. These large arachnoid cysts are bilateral lesions with the potential for severe surgical complications and a questionable possibility of cure. The authors recommend systematic radiological investigation to decide the appropriate therapy, including an analysis of the patency of the subarachnoid pathways with radionuclide cisternography and cystography. Simple cystoperitoneal shunting may be the appropriate therapy for most of these large lesions. (Neurosurgery, 6: 76--81, 1980).

Hypertrophied Thyroid Tissue in a Thyroglossal Duct Remnant

A 37-year-old woman was evaluated for a neck mass. This was located in the midline below the hyoid bone. Thirty-three years had elapsed since she had undergone subtotal thyroidectomy for hyperthyroidism. Eight years prior to examination, the patient had discontinued her thyroid maintenance medications. She had discovered the mass eight months prior to examination. Thyroid scan (Fig. 1) showed intense uptake in the mass. At operation the mass was attached to the midportion of the hyoid bone by a small fibrous band, as is usual in a thyroglossal duct remnant. Biopsy results showed diffuse thyroid hyperplasia. Thyroglossal duct remnants are known to harbor cysts or thyroid carcinoma, but growths of compensatory hyperplastic tissue are unusual.

Computed cranial tomography and radionuclide cisternography in hydrocephalus

Computerized Cranial Tomographic scanning has replaced radionuclide cisternography in screening both adult and pediatric patients for hydrocephalus. Nevertheless, cisternography provides indispensable information about the CSF clearance capacity and remains a valuable adjunct to the excellent anatomic detail provided by CCT scans. In patients without emergency symptoms, cisternography provides the best indication as to whether or not diversionary shunting is likely to relieve the patients symptoms.

The efficacy of radionuclide liver and bone scans in the evaluation of gynecologic cancers

Between 1978 and 1980, 33 patients with cervical cancer, 40 patients with ovarian cancer, and 28 patients with uterine cancer underwent clinical diagnostic staging. Fifty‐four patients had bone scans, and 101 patients received liver scans as a part of their staging work‐up. No positive bone scan results were found. Eight of 33 patients with Stage IV disease had positive liver scan results consistent with hepatic metastases. Only 1 of 69 patients with Stage I‐III disease had a positive test for metastases. While these numbers are small, the authors conclude that bone and liver scanning in asymptomatic patients with early stage gynecologic cancers may not be warranted as staging procedures.

Measure of blood flow by the multiple radioactive microsphere technique in radiated gastrointestinal tissue.

IN THIS STUDY, TWO DIFFERENT radioactive microspheres were used to measure blood flow of an irradiated segment of small intestine in four dogs before, and 12 days after, irradiation with 2000 rad. The technique and implications are discussed. Using multiple radioactive microspheres, the study demonstrated an increased blood flow in irradiated tissues twelve days after a single dose of 2000 rad. There was also an increase in blood flow to adjoining nonradiated segments of intestine in the same animal. These observations may be of significance in clinical applications of radiation therapy and surgery. A major surgical concern is the impaired healing of irradiated tissue in the immediate postradiation period. The mechanism of this has generally implicated decreases in the perfusion of irradiated tissue. No decrease in blood flow was shown in this study, suggesting that other mechanisms, e.g., stem cell depletion, should be considered. Further studies of this type are recommended to increase understanding of the blood flow in irradiated tissue.

Calyceal pertechnetate as a false-positive focus of ectopic gastric mucosa.

This case report describes a patient in whom concentration of Tc-99m pertechnetate in a renal calyx created a false diagnostic impression of ectopic gastric mucosa. The administration of furosemide demonstrated the benign cause of the focus.