The purpose of this study is to describe a new technique for en bloc temporal bone resection using a diamond threadwire saw (T-saw) as an alternative to cutting the temporal bone with an osteotome. This technique has been performed in 10 patients with external auditory canal and middle ear cancers without any injury to the internal carotid artery or jugular vein. The authors conclude that the use of a diamond threadwire saw after transposing the internal carotid artery anteriorly is a safe, simple, and reliable technique for en bloc temporal bone resection.
Hiroyuki Jimbo, Shinetsu Kamata, Kouki Miura, Tatsuo Masubuchi, Megumi Ichikawa, Yukio Ikeda and Jo Haraoka
Akira Ishii, Hideo Chihara, Takayuki Kikuchi, Daisuke Arai, Hiroyuki Ikeda and Susumu Miyamoto
The durability of embolization of large aneurysms is enhanced by use of the neck-bridging stent. However, it remains unclear what factors contribute to decreased recanalization. The purpose of this study was to demonstrate the contribution of the straightening effect of the parent artery to the durability of stent-assisted coiling for large aneurysms.
Of the 182 aneurysms treated by embolization since the introduction of the neurovascular stent, 82 consecutive unruptured aneurysms with a diameter greater than 7 mm were selected. There were 52 aneurysms treated with a stent (Group S) and 30 treated without a stent (Group NS). Occlusion status was evaluated 12 months after embolization with digital subtraction angiography. The vascular angle of the parent artery was measured before, immediately after, and 12 months after embolization. The rates of recanalization were compared between Group S and Group NS. In Group S, the rates of recanalization were further compared between those aneurysms with and without a significant angle change.
The rate of major recanalization was 9.6% in Group S and 26.7% in Group NS. The volume embolization ratio was 32.6% in Group S and 31.6% in Group NS, with no statistically significant difference. However, the angulation change before and after coiling was significantly higher in Group S (10.6°) than in Group NS (0.9°). The difference in the angulation was more evident 12 months after coiling (19.1° in Group S and 1.5° in Group NS). In Group S, recanalization was found in 14.3% of 35 stented aneurysms without a significant angular change when a significant angular change was defined as more than 20°. In contrast, all 17 aneurysms with ≥ 20° of angular change remained occluded.
Significant angular change of ≥ 20° most likely leads to decreased recanalization following stent-assisted embolization of large aneurysms.