Macular edema secondary to retinal vein occlusion is the sight-threatening condition clinicians fear. Previous studies have shown that early responders (ERs) who respond well to anti-VEGF injections within three months of treatment have better outcomes as measured by best visual acuity (BVA) and central subfield thickness (CST) at 12 months post injection initiation compared to limited early responders (LERs). This study analyzed whether early responder eyes continue to respond better than limited ER eyes over longer periods. This study also aimed to identify baseline comorbidities associated with response status.

The retrospective cohort study included patients over age 18 with RVO-related macular edema treated with anti-VEGF injections. 

Patients were categorized as ERs or LERs. LER eyes were defined as having CST reduction <10 percent, BVA gain <5 ETDRS letters, or both at three-months after anti-VEGF initiation. BVA and CST changes over the 24- and 36-month period following first anti-VEGF treatment were compared between ERs and LERs. Patient characteristics and systemic comorbidities were identified by chart review. Statistical analysis involved Levene test, Welch’s t-test and Welch’s ANOVA.

Main outcome measures included BVA and CST changes over the initial 24- and 36-month periods following treatment. 

The 24-month cohort included 68 ERs and 39 LERs, and the 36-month cohort included 58 ERs and 33 LERs. Here are some of the findings:

  • At 24 months, significant differences were found in BVA and CST gains between ER (+19.8 letters, and LER (-2.4 letters, -90.1 um)(p<0.0001; p<0.01). 
  • At 36 months, significant differences were found in BVA and CST gains between ER (+17.7 letters, -229.3 um) and LER (+1.3 letters, -128 um) (p<0.001; p<0.05). 
  • After controlling for differences in baseline BVA and CST, only the 24-month change in BVA remained significant (p<0.001). 
  • No significant associations were found between response status and cardiopulmonary, endocrine or oncologic comorbidities.

Investigators found that early-responder eyes with BRVO and CRVO had better functional responses to anti-VEGF injections at 24 months compared to limited early responder eyes even after controlling for baseline differences. They added that early identification of eyes as early responders or limited early responders in BRVO and CRVO may predict long-term functional prognoses.


Ophthalmol Retina 2023; Aug 16. [Epub ahead of print].

Kailar RS, Kuo BL, Perkins SW, et al.

DALK Outcomes in Keratoconus

Scientists investigated the effect of the keratoconus stage using the Amsler-Krumeich classification system and associated parameters on deep anterior lamellar keratoplasty outcomes.

They determined the preoperative KC stage and presence of corneal scarring and recorded the preoperative and postoperative best-corrected visual acuity, refractive error, mean central keratometry (Kmean) readings, topographic astigmatism and minimum corneal thickness (CT) values. They also noted the intraoperative and postoperative complications.

A total of 137 eyes (54 eyes in stage 3 and 83 eyes in stage 4) were included. The mean follow-up period was 42.2 ±24.36 months. Here are some of the findings:

  • No statistically significant differences were found between stage 3 and 4 KC groups for postoperative BCVA, Kmean, CT, spherical equivalent and topographic astigmatism values (each p>0.05). 
  • The effect of preoperative BCVA, Kmean, CT and refractive error values on postoperative BCVA couldn’t be demonstrated (p=0.264). 
  • No statistically significant correlation was found between postoperative and preoperative values (each p>0.05). 
  • Although intraoperative Descemet’s membrane perforation and postoperative early suture loosening were observed more frequently in stage 4 KC than stage 3 KC, the two groups were statistically similar for these and other complications (each p>0.05).

Scientists wrote that preoperative keratoconus stage and parameters used in classification weren’t useful in predicting postoperative deep anterior lamellar keratoplasty outcomes. As such, they suggested that the timing of surgery should be planned with the understanding that progression of the disease won’t have a negative effect on outcomes.


Cornea 2023; Aug 21. [Epub ahead of print]

Kemer Atik B, Emul M, Kirgiz A, et al.