Cranial irradiation--an unusual cause for diabetes insipidus.

Central diabetes insipidus frequently occurs due to tumours in the region of pituitary or hypothalamus or following surgical trauma to these regions. Rarely it has been reported following cranial irradiation. We report the case of a middle aged woman who underwent surgical removal of a frontal capillary hemangioblastoma and received cranial irradiation. She presented ten months later with features of diabetes insipidus which was confirmed to be of central origin. She responded well to desmopressin nasal spray. Radiation induced damage to the hypothalmo-pituitary axis presents usually with anterior pituitary hormone deficiencies, most commonly that of growth hormone. Presentation as central diabetes insipidus is very uncommon.

Hemangioblastoma of the posterior fossa: the role of multimodality treatment

The authors made a review of a series of patients with hemangioblastomas of the posterior fossa treated between 1973 and 1993. A total of 32 patients were analyzed with 24 patients receiving resection, 8 patients receiving radiosurgery and 2 patients receiving conventional radiotherapy. The mortality in the patients with a resection was considered acceptable with 2 deaths (8 percent) and with a morbidity of 3 patients (12.5 percent). A review of the literature suggests that conventional radiotherapy with high doses (45-60Gy) may have a role in the post-operative control of hemangioblastomas and in some cases could be employed even before the resection in order to facilitate the surgery. The radiosurgical treatment is regarded like adjuvant. Poor results were obtained with radiosurgery in large tumors where low doses (less than 20 Gy) were used. Because of the rarity and complexity of these tumors, mainly when associated with von Hippel-Lindau disease, a multicenter study could be useful with the assessment of the optimal utilization and combination of these treatment modalities.