Nakamine Sakari, Sakai Hiroshi, Arakaki Yoshikuni, Yonahara Michiko, Kaiya Tadayoshi
Ophthalmology, University of the Ryukyus, 207 Uehara, Nishihara, Okinawa, 903-0215, Japan.
Kaiya Eye Clinic, Hamamatsu, Shizuoka, 430-0903, Japan.
Jpn J Ophthalmol. 2018 Jan;62(1):48-53. doi: 10.1007/s10384-017-0533-x. Epub 2017 Nov 1.
To study the effect of the internal fixation lamp on anterior chamber width measured by anterior segment optical coherence tomography.
In a prospective cross sectional observational study, consecutive 22 right eyes of 22 patients (4 men and 18 women) with suspected primary angle closure underwent swept source domain anterior segment optical coherence tomography (AS-OCT), (CASIA SS-1000, Tomey, Nagoya, Japan). Anterior chamber parameters of angle opening distance (AOD), trabecular-iris angle (TIA), angle recess area (ARA) at 500 or 750 µm from scleral spur and pupil diameter were measured by AS-OCT in a three-dimensional mode in 4 quadrants (superior, inferior, temporal and nasal) in dark room setting both with and without internal fixation lamp.
Anterior segment parameters of AOD 500 in superior, inferior and temporal quadrants, AOD 750 at superior and nasal, TIA 500 at superior, and inferior and TIA 750 at superior and nasal, and ARA 500 or 750 at superior and inferior with internal fixation lamp were greater and the pupil diameter was significantly (all P < 0.05, paired t test) smaller than when measured without fixation lamp.
Internal fixation lamp of the anterior segment OCT makes the pupil constrict and angle wider. When using AS-OCT with usual setting with internal fixation lamp on with eyes in which the anterior chamber angle is narrow but open, it is recommended that the internal fixation lamp be turned off to ensure a clear indication as to whether the angle is open or closed in the dark.
研究内固定灯对眼前节光学相干断层扫描测量的前房宽度的影响。
在一项前瞻性横断面观察性研究中，对22例疑似原发性闭角型青光眼患者（4例男性和18例女性）的连续22只右眼进行扫频源域眼前节光学相干断层扫描（AS-OCT）（CASIA SS-1000，日本名古屋多美公司）。在暗室环境下，使用AS-OCT以三维模式在4个象限（上方、下方、颞侧和鼻侧）测量距巩膜突500或750 µm处的房角开放距离（AOD）、小梁-虹膜夹角（TIA）、房角隐窝面积（ARA）以及瞳孔直径，测量时分别开启和关闭内固定灯。
开启内固定灯时，上方、下方和颞侧象限的AOD 500、上方和鼻侧的AOD 750、上方的TIA 500、下方的TIA 500以及上方和鼻侧的TIA 750，还有上方和下方的ARA 500或750等眼前节参数均大于关闭内固定灯时，且瞳孔直径显著更小（所有P < 0.05，配对t检验）。
眼前节OCT的内固定灯会使瞳孔收缩且房角变宽。对于前房角狭窄但开放的眼睛，在使用常规设置且开启内固定灯的AS-OCT时，建议关闭内固定灯，以确保在暗室中能明确判断房角是开放还是关闭。
