My Most Prized Possession

Two tools are in my pocket every waking clinical hour, and truth be told, they often end up in my pocket even during vacation: my goniolens and a 78 D lens chosen for its clarity and the compromise position it takes between a 60 D and a 90 D. Neither of these, though, is my most prized professional possession.

A few years back during a trip to Salt Lake City, I had a morning to browse the used bookstores downtown. In a backroom filled with history and medical books, displayed on its own shelf, was a pristine copy of Robert Shaffer’s Stereoscopic Manual of Gonioscopy, complete with the original Viewmaster reels and viewer in the back. I believe I saw a halo around it.

At the dinnertime meeting that night, I canvassed the local glaucoma doctors to see if they had any idea who might have sold such a precious volume. No one knew or fessed up that they had sold it.

Shaffer’s noble attempt at a gonioscopy atlas set the gold standard until the famous collaboration in Iowa City that led to Lee Alward’s excellent atlas of the angle Color Atlas of Gonioscopy and his subsequent website (www.gonioscopy.org). Sadly, the Viewmaster factory in Beaverton, Ore., is long gone, replaced by a strip mall, but the hope of better 3-D views of ocular structures, in particular the angle, is on the immediate horizon. 3-D camcorders and monitors are readily available for home viewing (though recent literature suggests that they may have problems, such as high eye fatigue, with their long-term use).

Although an essential component of the glaucoma exam, evaluating the angle isn’t done nearly often enough, and accurate evaluation requires practice and a standardized system of grading. Many angles taper superiorly so that the angle is less open at 12 o’clock than at 6 o’clock. The angle may undergo diurnal changes in its overall configuration; this is poorly understood. Everyone should use a grading system for the angle. Myself, I am a fan of both the Shaffer and the Spaeth systems, and I urge the reader to be familiar with both (see the gonioscopy section in The Glaucoma Book by Schacknow and Samples, 2010).

I think the current, single greatest threat to good gonioscopy is the challenge of recording the appearance of the angle with electronic health records. The majority do not provide any utility for drawing the angle, and those that do make it very awkward. A recent template I was given for a newly acquired EHR system provides four choices for the opening of the angle and four choices for pigmentation at four locations, hardly adequate for the next patient I saw, who had intermittent peripheral anterior synechia associated with prior filtering surgeries for iridocorneal endothelial syndrome.

Gonioscopy is an art, one that is needed for the evaluation of the narrow angle when more sophisticated instruments are not available. This skill is something that we all need to study so that we can do it better.

This issue of Glaucoma Management is devoted to the narrow and closed angle and covers the most pressing controversies in the management of narrow-angle patients by some of the best international experts.