Editors Selection IGR 20-3

Surgical Treatment: What if it were you?

Rupert Bourne
Sokratis Zormpas

Comment by Rupert Bourne & Sokratis Zormpas on:

80960 Glaucoma surgery preferences when the surgeon adopts the role of the patient, Chang TC; Vanner EA; Parrish RK, Eye, 2019; 33: 1577-1583

Find related abstracts

This paper reports the results of a survey in 2018 of 27% of American Glaucoma Society (AGS) members (n = 289) which asked them to imagine they were a glaucoma patient and then their preference of glaucoma procedure. The clinical scenario presented was that of a primary open-angle glaucoma patient with normal visual acuity, adherent taking all commercially available glaucoma medications, but with inadequate intraocular pressure (IOP) control and progressive visual field loss. The members were asked to choose one procedure from a list of 15 surgical options under each of three preoperative IOP levels.

Ab interno trabeculotomy was the most frequently chosen procedure (20%), followed by the Xen gel stent (19%)

Overall, ab interno trabeculotomy (gonioscopy-assisted transluminal trabeculotomy [GATT] or Trab360) was the most frequently chosen procedure (20%), followed by the Xen gel stent (19%), iStent with two devices (14%), traditional trabeculectomy augmented with mitomycin C (14%), and glaucoma drainage devices (GDD; Ahmed/Baerveldt; 7%). The authors were able to compare these findings to a survey of AGS members in 2016,1 who were asked which procedure they would choose to offer to a hypothetical patient with glaucoma, where 59% had chosen a traditional trabeculectomy with MMC and 23% a GDD. The authors suggest that the decreased preference of either procedure in the most recent survey may be due an increase in the perceived risks (potential loss) when the AGS participants adopted the patient role, which would support the notion that loss aversion can alter the perceived risk/benefit ratio when an individual's perspective is shifted from that of a surgeon (expected utility theory) to that of a patient (prospect theory).2

This approach is intriguing as other studies have shown that doctors' recommendations are affected by cognitive biases, for example among retina specialists who select different age-related macular degeneration treatments for themselves than for hypothetical patients.3 At lower preoperative IOP levels, more participants preferred non-bleb forming and/or conjunctiva-sparing procedures, which is also interesting as it suggests that the perceived risk associated with bleb-forming or conjunctiva-violating procedures outweighed concerns over relative lack of efficacy. Although there are several limitations of this study which the authors give due consideration, it does make one reflect on one's own biases in making surgical decisions - perhaps we all need to read Kahneman!2


  1. Vinod K, Gedde SJ, Feuer WJ, et al. Practice preferences for glaucoma surgery: a survey of the American Glaucoma Society. J Glaucoma. 2017;26:687-693.
  2. Kahneman D, Tversky A. Prospective Theory: An Analysis of Decision under Risk. Econometrica. 1979;47:263-292.
  3. Jeng KW, Wilgucki J, Halperin S, et al. Retina specialists treating age-related macular degeneration recommend different approaches for patients than they would choose for themselves. Retina. 2014;34:1796-1801.

Issue 20-3

Select Issue