脳外科領域に於ける疼痛閾値の研究〔第1報〕—（1）深部痛覚閾値について

A Study, on the Threshold in Sensation of Pain [1] : Pain in Depth

緒言

　疼痛は臨床的に最も？々遭遇する重要な症状で，診断的価値も甚だ大きいにも拘らず，その分析，処置に多大の困難を感ずることのあるのは，主にその主観的な性質によるものである。疼痛研究の第一歩として，疼痛閾値を測定することは，この意味に於いて重要であつて，古くから各種の試みがなされて来た。

　Hardy,Wolff　＆　Goodellの輻射線疼痛計^1），Gluzekの深部疼痛計^2）3），及び竹林，河原式深部痛覚計^4）はその代表例である。前者は皮膚の表在性痛覚，後者は皮膚の表在性痛覚を除いた所謂深部痛覚の測定であるが，輻射線疼痛計に比し，深部疼痛計の特徴は，利用が簡便，甚だ臨床的であることであろう。

Using coiled spring esthesiometer which was made by the author, length 30 cm., weight 110 gm., pain threshhold was measu-red. The force exerted on the tissue by the rounded ebonite tip of the plunger, 10mm in diameter, was read from a scale which indi-cated the degree of compression of the steel spring. The pain threshold measurements were obtained by placing the plunger tip upon the forehead and increasing the pressure (1 kg./5minutes) until the subject reported pain. Every effort was made to direct the plunger perpendicular to the calvarium, thus to avoid dragging or pulling the skin.

From the experiments of 0.05% percamine injection, it was inferred that the subcutaneous and periosteal tissues were the primary sites of noxious stimulation.. Pain threshold was found to be relatively stabilized on the fore-head, and its mean pressure which required to evoke pain in 66 adult subjects was O.58kg. Noticeable differences on five trained adult subjects showed the same results with Hardy's apparatus.

Experiments on the influence of skin tem-perature were performed on 10 trained adult subjects.