Glaucoma Implant Outcomes Observable With EHR Data

Electronic health records show the differences in patient outcomes with Ahmed and Baerveldt implants.

Automated electronic health record (EHR) extraction can potentially be used to assess outcomes of tube shunt surgery, according to a poster presented at the 2022 annual meeting of the American Academy of Ophthalmology (AAO), held in Chicago September 30 to October 3. 

The study analyzed EHR data from 803 eyes treated with Ahmed or Baerveldt implants. The investigators assessed the patients’ intraocular pressures (IOP), visual acuity (VA), hypotony (defined as <6 mm Hg), and return to clinic (RTC) at postoperative month 6. 

Investigators report the baseline IOP was higher in the Ahmed group (n=526) than Baerveldt (n=277) (28.0 vs 22.0 mm Hg; P <.01), and VA was worse with 27.5% of the Ahmed implant patients returning between postoperative months 3 and 12 with acuities of 20/200 or worse, vs 17.4% in the Baerveldt implant group (P < .01). 

The decrease in intraocular pressure (IOP) at postoperative month 6 was also greater in the Ahmed group than the Baerveldt group (-13.2 vs -10.8 mm Hg; P =.02). A similar proportion in both groups had a 30% reduction or more in IOP, with 66.9% seeing such a drop in the Ahmed group vs 67.7% in the Baerveldt group (P = .82). The cumulative failure rate at postoperative month 12 was 32.3% in the Ahmed group vs 35.0% in the Baerveldt group (P =.27). 

The median IOP at postoperative month 6 was 15.0 mm Hg in the Ahmed group vs 12.0 mm Hg in the Baerveldt group (P < .01). Ahmed valves lowered IOP more quickly and with fewer follow-ups, the researchers report. 

Hypotony rates did not differ between groups. Regression analysis determined an association between hypotony and Baerveldt/secondary glaucoma with a RTC and increased VA loss.


Shen L, McGlumphy E. Leveraging the EHR to assess Ahmed vs Baerveldt implantation: a single-center comparative study. Poster presented at: The American Academy of Ophthalmology 2022 Annual Meeting; September 30 to October 3, 2022; Chicago. PO125.