ブロモクリプチン治療中にけいれん発作を生じたプロラクチン産生腺腫:腺腫の鞍外側方進展様式とけいれん発現との関係

Seizures as a late complication of bromocriptine therapy in patients with prolactin-producing macroadenomas:correlation between lateral extension of the adenoma and seizure onset

I．はじめに

　海綿静脈洞への側方進展を伴うプロラクチン（以下PRL）産生腺腫9症例に対してブロモクリプチンの単独大量投与を行い，うち3例で治療経過中にけいれん発作を認めた．下垂体腺腫の鞍外側方進展様式とけいれん出現時のMR所見から発作の発現機序について検討したので報告する．

Seizures have been reported as a late complication of medically treated prolactin-producing macroadenomas with lateral extension.

Nine prolactin-producing macroadenomas with lateral extension to the cavernous sinus were treated with bro-mocriptine alone. In all cases, rapid decrease of serum prolactin level was recognized and in eight cases, evi-dence of tumor shrinkage on CT or MRI was demon-strated. During medical treatment, symptomatic sei-zures occurred in three cases. MRI showed small re-sidual tumors on the medial surface of the temporal lobe in all these patients. Additionally, a hypointense signal on both T1- and T2-weighted images was recog-nized around the residual tumor. It was consistent with hemosiderin, a result of intratumoral hemorrhage caused by bromocriptine. On the contrary, the remaining six patients without seizures during treatment did not show abnormal hypointense signals on the medial sur-face of the temporal lobe.

Seizures occur with a high incidence as a late com-plication of medical treatment of prolactin-producing macroadenomas with intradural supracavernous exten-sion. The patients with seizure show hemosiderin de-posit, which may be the trigger of the seizure, within the medial surface of the temporal lobe after bromo-criptine therapy.