Iris ischaemic changes and visual outcome after acute primary angle closure.
BACKGROUND
Ischaemic changes in the iris occur frequently after an episode of acute primary angle closure (APAC). The aim of this study was to investigate the significance of such changes with regards to visual outcome.


METHODS
Acute primary angle closure cases were treated with medical therapy followed by laser peripheral iridotomy after resolution of the acute episode. Subjects were examined at 1, 4, 8, 12 and 16 weeks post laser peripheral iridotomy. Eyes were examined for signs of iris ischaemic changes (IIC), defined as the presence of iris whorling or stromal atrophy. Iris photographs were also taken at weeks 1, 8 and 16. Subjects requiring glaucoma medication or filtering surgery during the follow-up period were excluded. The visual acuity and visual field (using automated white-on-white threshold perimetry) at week 16 were used in the assessment of visual outcome.


RESULTS
Sixty-one subjects with APAC completed the study. The majority of subjects were female (82%) and Chinese (92%), and the mean age was 59 +/- 8.8 years. More than half the subjects (52.5%) were found to have developed IIC during the study, 65% of whom already had signs of IIC by the first week. Only 13 subjects (41%) with IIC and 6 subjects (21%) without IIC had an abnormal visual field defect at week 16 (P = 0.09). There was also no difference in visual acuity at week 16, the majority of subjects in both groups having visual acuity of 6/12 or better.


CONCLUSIONS
The development of iris ischaemic changes after a single episode of APAC may not be associated with an adverse visual outcome.
Loon
Seng-Chee
SC
National University Hospital, Singapore.
Chew
Paul T K
PT
Oen
Francis T S
FT
Chan
Yiong-Huak
YH
Wong
Hon-Tym
HT
Seah
Steve K L
SK
Aung
Tin
T
D000208:Acute Disease; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000959:Antihypertensive Agents / Q000627:therapeutic use; D005260:Female; D015812:Glaucoma, Angle-Closure / Q000150:complications* / Q000188:drug therapy / Q000601:surgery; D006801:Humans; D007429:Intraocular Pressure / Q000187:drug effects; D032801:Iridectomy; D007498:Iris / Q000098:blood supply* / Q000601:surgery; D007511:Ischemia / Q000209:etiology* / Q000601:surgery; D053685:Laser Therapy; D008297:Male; D008875:Middle Aged; D014792:Visual Acuity; D014794:Visual Fields
D000959:Antihypertensive Agents