Evaluation of Two-Dimensional (2D) versus Three-Dimensional (3D) Video Tutorials in Cataract Surgery for New Trainees.

Purpose Microscopic ophthalmic surgery requires an understanding of three-dimensional (3D) spaces within the eye. Recently, there has been an increase in 3D video training tools in health care. Studies have evaluated the efficacy of 3D tutorials in general surgery, but little has been published within ophthalmology. We present a randomized study evaluating differences in surgically naïve trainees after watching either a 2D or 3D phacoemulsification tutorial. Design This was a double-blind, randomized study. A group of third and fourth year medical students at our institution were randomized with stratified randomization based on prior surgical courses to control for differences in baseline surgical skill. The two study arms were watching 2D or 3D instructional videos on phacoemulsification (Richard Mackool). Methods Participants received a preliminary survey and participated in an hour-long microscopic surgery session. During the session, participants performed tasks evaluating baseline microscopic spatial awareness and surgical skill. The students were then instructed to watch either a 2D or 3D video on phacoemulsification based on their randomized study arm. During the postintervention session, participants performed the biplanar incision and capsulorhexis steps of cataract surgery discussed in the video on model eyes. Students were evaluated on speed and overall capsulorhexis quality. Results Thirty-one students qualified for the study and completed the microscopic surgery session. Students in both groups had similar baseline speed and quality of preintervention microscopic tasks ( p > 0.05 for all tasks). Postintervention, students randomized to the 3D video performed significantly faster than the 2D group for biplanar incision (11.1 ± 5.5 s vs. 20.7 ± 10.5 s, p = 0.001). There were no statistically significant differences found between the groups in capsulorhexis timing ( p = 0.12) or quality score ( p = 0.60). Conclusions 3D video surgical training tutorials may improve speed of certain steps of cataract surgery for surgically naïve ophthalmology trainees. Given the limited sample size of this study, further investigation of their effectiveness is warranted.

Physical changes in human meibum with age as measured by infrared spectroscopy.

Both lipids and mucins contribute to the stability of the tear film and lipids may inhibit tears from evaporating. Younger people have lower lipid viscosity, higher lipid volume, and a lower rate of tear evaporation. Since age-related changes in human meibum composition and conformation have never been investigated, as a basis for the study of lipid-associated changes with meibomian gland dysfunction, we used the power of infrared spectroscopy to characterize hydrocarbon chain conformation and packing in meibum from humans without dry eye symptoms in relation to age and sex. Meibum from normal human donors ranging in age from 3 to 88 years was studied. Meibum phase transitions were quantified by fitting them to a 4-parameter 2-state sigmoidal equation. Human meibum order and phase transition temperatures decrease with age and this trend may be attributed to lipid compositional changes. If meibum has the same thermodynamic properties on the surface of the tears as it does on the lid margin, a decrease in lipid-lipid interaction strength with increasing age could decrease the stability of tears since lipid-lipid interactions on the tear surface must be broken for the tear film to break up. This study also serves as a foundation to examine meibum conformational differences in meibum from people with meibomian gland dysfunction.