Axial length as a factor associated with visual outcome after vitrectomy for diabetic macular edema.
OBJECTIVE
To investigate whether axial length predicts visual acuity outcome after vitrectomy for diffuse macular edema secondary to diabetic retinopathy.


METHODS
Fifty-one eyes of 41 patients with diabetic macular edema (DME) who underwent vitrectomy were reviewed retrospectively. Clinical data, including axial length measured by partial coherence interferometry, postoperative best-corrected visual acuity (BCVA), and postoperative status of integrity of the photoreceptor layer observed by optical coherence tomography, were recorded. The relationship between axial length and postoperative BCVA or visibility of the junction between the inner and outer segment (IS/OS) line at 12 months after surgery were analyzed. Logistic regression analyses were performed to examine predictors related to postoperative BCVA.


RESULTS
Median BCVA improved significantly (P < 0.0001) after surgery (0.4 logMAR units; range, 0-1.5) compared to baseline (0.69 logMAR units; range, 0.22-1.22). Median axial length was significantly longer (P = 0.017) when postoperative BCVA was below 0.4 logMAR units (23.51 mm; range, 22.30-26.10) compared to over 0.4 logMAR units (23.02 mm; range, 22.10-24.65). A significant negative correlation was observed between postoperative logMAR and axial length (n = 51, rs = -0.35, P = 0.012). Median axial length was significantly longer (P = 0.039) in eyes with visible IS/OS line (23.54 mm; range, 22.39-26.10) than in those without visible IS/OS line (23.02 mm; range, 22.13-24.65) at 12 months after surgery. Multivariate logistic regression analysis showed that short axial length (odds ratio: 0.3, P = 0.009) increased the risk of poor visual outcome after surgery.


CONCLUSIONS
Longer axial length predicts better postoperative BCVA after vitrectomy for diffuse macular edema secondary to diabetic retinopathy.
Department of Ophthalmology, Tokyo Medical University, Tokyo, Japan.
Yoshihiro
Y
Wakabayashi
Keisuke
K
Kimura
Daisuke
D
Muramatsu
Yoshihiko
Y
Usui
Kazuhiko
K
Umazume
Jun
J
Suzuki
Hiroshi
H
Goto
D000328:Adult; D000368:Aged; D058452:Axial Length, Eye / Q000473:pathology*; D003930:Diabetic Retinopathy / Q000150:complications*; D005260:Female; D006801:Humans; D016015:Logistic Models; D008269:Macular Edema / Q000209:etiology / Q000473:pathology* / Q000503:physiopathology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D014792:Visual Acuity / Q000502:physiology*; D014821:Vitrectomy
axial length; diabetic macular edema; hyperlipidemia; optical coherence tomography; pars plana vitrectomy; photoreceptor layer