Stereotactic Radiosurgery

Stereotactic radiosurgery, in particular LINAC or Gamma Knife radiosurgery, can be used in select patients to provide a single, high dose of stereotactically localized radiation to the AVM nidus. This radiation dose causes endothelial damage, smooth muscle cell proliferation, progressive sclerosis and subsequent thrombosis of nidal channels over time. The success of stereo-tactic radiosurgery depends on AVM size and the radiation dose delivered. Several clinical studies have demonstrated that AVM obliteration can be expected between 1 and 2 years after radiosurgery, provided the AVM nidus is less than 2-3 cm in diameter or has a volume of less than 10 cc (Table 20.5) [7,13,15,20,21]. Long-term angiographic follow-up between 5 and 24 years after radiosurgery suggests that a small number of obliterated AVMs may recur, especially in pediatric patients. Larger AVMs or lesions with a diffuse nidus are generally not amenable to stereotactic radiosurgery. However, the use of specialized collimators, staged radiosurgery, embolization and microsurgery or repetitive radiosurgery may facilitate the treatment of some larger lesions. For example, large AVMs can be incrementally reduced in size with multiple endovascular embolizations until the nidus is smaller than 3 cm in diameter and thus amenable to radio-surgical treatment.

The selection of patients for stereotactic radiosurgery varies among institutions. In general, stereotactic radiosurgery should be considered when (1) surgical AVM excision is associated with an unacceptably high risk, (2) anesthetic risk is high because of the patient's medical condition, (3) surgery with or without

Cure Your Yeast Infection For Good

Cure Your Yeast Infection For Good

The term vaginitis is one that is applied to any inflammation or infection of the vagina, and there are many different conditions that are categorized together under this ‘broad’ heading, including bacterial vaginosis, trichomoniasis and non-infectious vaginitis.

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