12 Treatment of a Difficult MCA Aneurysm

HIROTOSHI SANO, VIRAL MEHTA, YOKO KATO, MINORU YONEDA, AND TETSUO KANNO

Diagnosis Difficult MCA aneurysm

Problems and Tactics Thrombosed aneurysm, misleading angiograms, direct reconstruction

Keywords MCA aneurysms, reconstruction, MCA stenosis

Case Report

A 10-year-old female presented with symptoms of headache and vomiting. Computed tomographic (CT) scan showed a giant right middle cerebral artery (MCA) aneurysm. Digital subtraction angiography (DSA) revealed two large aneurysms at the M₁ portion of the right MCA (Fig. 12–1A, B). The patient was referred (along with these imagings, which had been done at her own hospital) to Fujita Health University where three-dimensional CT angiography (3D-CTA) was performed. It showed a single, multilobulated giant aneurysm at the M₁ portion of the right MCA (Fig. 12–1C, D). The anterior choroidal artery appeared to be attached to the aneurysm. A right frontotemporal craniotomy was performed. The sylvian fissure was opened. There was a giant multilobulated aneurysm at the M₁ portion of the right MCA, contrary to the findings on DSA in which there appeared to be two large aneurysms located at the M₁ portion of the right MCA (Figs. 12–2A and 12–3A). Upon dissecting the aneurysm, it was found that the anterior choroidal artery was attached to the aneurysm; however, it was possible to dissect it and completely separate it from the aneurysm. The lenticulostriate arteries originated from the distal portion of the M₁ portion of the right MCA away from the aneurysm. The internal carotid artery (ICA), anterior cerebral artery (ACA), and MCA were dissected, and temporary clips were applied at the ICA after the anterior choroidal artery, at the M₁ portion of the MCA before the lenticulostriate arteries and at the A₁ portion of the right ACA. The aneurysm was punctured; however, only a small part of the aneurysm was seen collapsed (Fig. 12–2B