Purpose:
To compare subjective visual perceptions and pain during vitreo-retinal (VR) and cataract surgery under local anesthesia (LA).
Methods:
Sixty-eight patients undergoing VR surgery under LA in a teaching hospital VR unit were included (Group A). Age and sex matched controls were selected from patients undergoing cataract surgery under LA (Group B). Visual perceptions and pain scores (during anesthesia and the VR procedure separately) were compared in the two groups. Statistical analysis was performed using Microsoft Excel® software.
Results:
Patients' experiences of seeing colour and light and also pain scores were significantly different between the two groups (p<0.001 for colour and light sensations, Fisher’s exact test (FE-test); p<0.001 for pain sensation, t-test) but perception of movement was not significantly different (p=0.36, FE-test).(See table)Among the patients in the vitreoretinal group, pain scores were higher with duration of surgery (p=0.005, t test), history of previous ocular surgery under LA (p=0.03, FE-test) and the type (eg. scleral buckling) of surgery (p<0.004, Chi-square test). There was no correlation between the intra-operative pain scores and visual perceptions (p>0.05, Spearman’s correlation).
Conclusions:
Subjective visual perceptions and also pain scores during vitreo-retinal surgery under LA are different from those in cataract surgery. With a increasing proportion of the VR procedures done under LA, this information can be useful in better pre-operative counselling of such patients.
Keywords: perception • vitreoretinal surgery • cataract