乳幼児先天性顔面神経麻痺の4症例—その成因論について

A UNILATERAL CONGENITAL FACIAL PALSY

　I．緒言

　新生児に観察される顔面神経麻痺の原因には鉗子分娩などによる顔面神経末梢枝の損傷，側頭骨内外における出血，血腫形成，あるいは顔面神経核の先天性形成不全などがあげられている。この他に，厳密には顔面神経麻痺とは言えないが，顔面表情筋の形成不全も考えられる。

　新生児の顔面神経麻痺に関する報告は数多く見られるが，Möbius（1888）をはじめとする先天性顔面神経核形成不全の症例の報告では，麻痺のほかに，他の奇形も多く合併し，出産後早期に死亡して剖検所見の得られる場合を除き，そのほとんどが機能的検査所見あるいは，X線所見などについて記載してあるに過ぎない。

　Four cases of congenital facial palsy, without any other physical anomaly are reported. The patients' history revealed normal births without any birth trauma. The facial palsy was noted in all cases within 10 days after birth. There was no history of having any disease except for an attack of otitis media in one case.

　There was a partial paresis in 1 case, a boy 2 years and 8 months old; a total paresis in two cases, boys, 2 years and 6 months and another at 1 year and 2 months old; and a paresis affecting only the oral angle in a girl, aged 3 years and 6 months.

　Following a thorough physiological examination of topology the course of the facial nerve in the temporal bone was examined surgically.

　In one case the facial nerve was found to be situated in an anomalous position; while in two cases there were anomalous stapes and the long foot of the incus. In the last case the facial nerve was found to be normal but it was considered that the paresis was due to hypoplasia of the depressor anguli oris muscle.

　Gleaning from these surgical findings, the authors maintain, that congenital facial palsy may be manifested as results of middle ear anomalies, especially from that of the second branchial arch without any pathological factors involving the facial nerve per se.