Abstract
Purpose:
The purpose of this study is to determine whether pre-operative extremes of anterior chamber depth (ACD) and axial length (AL) are associated with increased rates of untoward events during cataract surgery and/or poor visual outcomes.
Methods:
This study involved a retrospective analysis of 4,923 cataract surgery cases from the VA Ophthalmic Surgical Outcomes Data Project. Pre-operative ACD & AL were measured using Optical Interferometry or A-scan ultrasound biometry. Pre- and post-operative visual acuity (VA) was measured via Snellen chart. The NEI Visual Function Questionnaire-25 (NEI-VFQ) was administered pre- and post-operatively. Events and outcomes analyzed included posterior capsular tear (PC tear), intra-operative zonular dehiscence, intra-operative iris trauma, persistent corneal stromal edema at 1 month, target refraction missed by > .75 diopters, VA and NEI-VFQ scores. P-values were calculated using the Fisher exact test and t test.
Results:
Of the 4,923 cases reviewed 451 had shallow ACD (< 2.6mm), 1351 had deep ACD (>3.33mm), 111 had Short AL (< 22mm) and 705 had long AL (> 25mm) recorded. Deep ACD, Short AL and Long AL were associated with an increased rate off target post-operative refraction (p values< 0.05); Deep ACD and Short AL were associated with an increased risk of intra-operative iris trauma (p values<0.05). Shallow or deep ACD and short AL were associated with an increased risk of intra-operative zonular dehiscence (p values= 0.02, 0.03, 0.01 respectively). Shallow ACD was associated with persistent postoperative corneal edema at 1 month (p value=0.02). None of the extreme ACD or AL variables were statistically significant for posterior capsular tear compared to normals. Short AL showed statistically significant less improvement in post-operative composite NEI-VFQ results (p value<0.01) compared to normals, while shallow ACD and short AL had an average post-operative VA that was statistically less compared to normals (p values <0.01). All groups showed a statistically significant improvement in post-operative VA compared to pre-operative VA (p values <0.01).
Conclusions:
Extremes of ACD and AL in cataract surgery may render the patient more at risk for certain untoward intra-operative events and poorer visual outcomes.
Keywords: 445 cataract •
420 anterior chamber •
462 clinical (human) or epidemiologic studies: outcomes/complications