Vascular complications of thorium dioxide

Effects of radiation on cerebral vasculature: a review

Radiation therapy plays a critical role in the treatment of central nervous system neoplasms and cerebral arteriovenous malformations. The deleterious effects of radiation on cerebral arteries may be the primary limitation to these treatment methods, as radiation may cause a variety of cerebrovascular injuries and hemodynamic changes. Radiation-induced changes in the cerebral arterial wall are determined by a number of cellular processes in endothelium and smooth muscle cells that modulate differences in radiosensitivity and phenotypic expression. The histopathological findings in arterial radiation injury include vessel wall thickening, thrombosis, luminal occlusion, and occasional telangiectases. Mechanisms for radiation injury to blood vessels include phenotypic changes in normal vessel wall cells (especially endothelium) manifested by the expression or suppression of specific gene and protein products that affect cell cycle progression or cellular proliferation or demise via cytotoxic injury or apoptosis. This review describes the molecular and cellular events involved in the systemic and cerebral vascular response to radiation and the potential means by which these responses may be influenced to augment the therapeutic effects of radiation while minimizing the untoward consequences.

Thorotrast associated nodular regenerative hyperplasia of the liver

A case of nodular regenerative hyperplasia (NRH) of the liver is described in association with exposure to the radiographic contrast medium Thorotrast. This is the first case in which the pathological findings have been fully documented. It is suggested that NRH may have developed through Thorotrast induced damage to portal vein radicles.

Cervical Thorotrast granuloma: a review of the literature and a new treatment modality

Extravasation of thorium dioxide after transcervical carotid angiography has resulted in persistent open draining neck wounds. These difficult problems have remained a challenge for the treating head and neck surgeon. Neck dissection has been the mainstay of treatment in the past; however, this has been fraught with complications. The application of doxycycline sclerosis is described in the successful resolution of a large thorotrast granulomatous neck wound. A review of the literature and the management options of Thorotrast granulomas are discussed.

Thorotrast and the liver--revisited

BACKGROUND

Thorotrast, a radiological contrast medium that was widely used from 1928-1955 is a thorium dioxide colloid that has been neutralized and stabilized by colloid, composed of dextran. The major site of deposition is the reticuloendothelial system where it is retained for a long time.

CASE REPORTS

Complications occurring late after exposure to thorotrast are described in two patients.

RESULTS

One patient had angiosarcoma of liver metastatic to bone and bone marrow failure after a 43 year latency period. The other patient had a thorotrast granuloma and angiosarcoma of the liver after 22 year and 28 year latency periods respectively.

CONCLUSIONS

Complications due to thorotrast appear to represent consequences of chronic alpha irradiation.

Late effects of perivascular injection of Thorotrast in the neck

Two cases of late sequelae of accidental perivascular injection of Thorotrast (thorium dioxide) during carotid arteriography are presented. The complaints of the patients and the clinical findings are due to topical granulomatous and fibrous reactions with compression of the carotid artery and cranial nerves, and influence upon larynx and trachea. For future decades it will still be necessary to be aware of this possible cause of neck tumours with oto-laryngeal and neurological symptoms.