腰部椎間孔部腫瘍に対する傍脊柱筋アプローチ

Paraspinal Approach to Lumbar Foraminal Tumor

Ⅰ．はじめに

　腰部椎間孔部腫瘍は，良性である神経鞘腫もしくは神経線維腫であることが多く，全摘出が治癒へ至る近道である．しかし同部へのアプローチは疾患の頻度が少ないため，なかなか慣れないものである．今回筆者らは，Eden Ⅳ型（Table 1）⁴⁾の腰部椎間孔部腫瘍に対して傍脊柱筋アプローチを用いることによって良好な結果を得たため，その経験をもとに本手術アプローチにおけるコツや本腫瘍摘出における筆者らの基本手技について述べる^2,11,12)．

　Objective：To treat lumbar foraminal tumors, the chosen operative approach depends on the tumor location and size. Although total facetectomy and the combined intra- and extraspinal canal approach provide a wide operative field, facet fusion is required and the procedure is invasive. We report the successful removal of Eden type Ⅳ tumors using only the paraspinal approach without complete facetectomy.

　Patients and Methods：We treated 4 patients with lumbar foraminal tumors. All were Eden type Ⅳ (neurofibroma, n=3; schwannoma, n=1) and all were removed via the paraspinal approach without total facetectomy and the intraspinal canal approach. Although total facetectomy was not needed to remove the intraforaminal component, phased foraminal expansion with a SONOPET (m&m Co., Ltd., Tokyo, Japan) device was required in all cases. Intratumoral decompression was performed with probe for tumor and PAL-Ⅰ and EMG recordings were obtained with direct stimulation of the nerve root.

　Results：All tumors were completely removed via only the paraspinal approach; neither total facetectomy and fusion, nor the addional intraspinal approach was required. There was no tumor recurrence or lumbar instability during the follow-up period.

　Conclusions: To remove the intraforaminal component of Eden type Ⅳ tumors, phased expansion of the foramen with a SONOPET and intratumoral decompression with CUSA and PAL-Ⅰ are required and effective. Using these devices, this less invasive approach is useful for the treatment of patients with lumbar foraminal tumors of Eden type Ⅳ.