technetium-tc-99m-exametazime and Paraganglioma

Paraganglioma of the sellar area is extremely rare with only six cases having been reported in the literature. Surgical removal of these tumors is difficult, and the transsphenoidal approach usually results in limited resection. Most authors who published reports on this tumor recommended radiation therapy after partial removal of the tumor. However, considering the benign nature of these tumors, the risk of radiation-induced endocrine insufficiency and optic neuropathy and the lack of proven effectiveness of radiotherapy, its value remains controversial. We describe a 48-year-old woman with parasellar paraganglioma who presented with headaches, visual loss and oligomenorrhea. Magnetic resonance imaging (MRI) showed an invasive tumor in the sellar and parasellar areas which extended to both cavernous sinuses and compressed the optic chiasm and the left internal carotid artery. Surgery by the transsphenoidal approach enabled only limited biopsy of the tumor. The patient was reoperated by an extended pterional approach which resulted in a subtotal removal of the tumor and adequate decompression of the adjacent structures. She received no adjuvant treatment during the 8-year postsurgical follow-up and remained in good health. A repeated MRI showed no change in the size of the residual tumor. Contrary to the therapeutic recommendations described in previous reports, we favor postoperative adjuvant therapy only if the symptoms or signs of cranial nerve compression persist following maximal tumor removal, or if there is evidence of subsequent growth of residual tumor.

Topics: 3-Iodobenzylguanidine; Combined Modality Therapy; Female; Humans; Magnetic Resonance Imaging; Middle Aged; Paraganglioma; Pituitary Neoplasms; Radiopharmaceuticals; Radiosurgery; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

To determine whether the absolute value for the stump pressure might be a useful index of symmetrical cerebral blood flow (CBF), and to examine correlations with the stump pressure ratio (initial mean stump pressure/preocclusion mean arterial pressure), fifty candidates for ICA injury or permanent occlusion were evaluated preoperatively. Each was continuously monitored for mean stump pressure and arterial pressure before, during (for a total of 20 min), and after balloon test occlusion. During the occlusion, CBF was measured by 99 m Tc-hexamethyl-propyleneamine oxime (99 m Tc-HMPAO) single photon emission computed tomography (SPECT). The stump pressure and the stump pressure ratio were then compared with the results of 99 m Tc-HMPAO SPECT. Patients who failed to tolerate even brief periods of carotid occlusion and showed asymmetric decreases in CBF on SPECT were divided into high and moderate risk groups. Those with no significant changes in CBF on the occluded site formed the minimum risk group. Mean stump pressure was over 50 mmHg in 10 of a total of 25 patients in the high and moderate risk groups, and below 50 mmHg in 5 of the 25 patients in the minimum risk group. The stump pressure ratio did not exceed 56% in any but two patients in the high and moderate risk groups, and values were at least 60% in all patients of the minimum risk group. Decrease of CBF in two moderate risk group cases was localized in the posterior circulation. Difference in symmetrical CBF between the stump pressure ratio vs. the absolute value of mean stump pressure were statistically significant (p < 0.01, Fisher's Exact Test). Maintenance of a stump pressure ratio of 60% or more during test occlusion may be a more useful index for a good collateral circulation than any absolute value for mean stump pressure.

Topics: Blood Pressure; Brain Neoplasms; Carotid Artery, Internal; Carotid Stenosis; Catheterization; Cerebrovascular Circulation; Electroencephalography; Granuloma; Humans; Intracranial Aneurysm; Meningioma; Paraganglioma; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Treatment Outcome; Vascular Surgical Procedures