First-visit diagnosis of preperimetric glaucoma

Abstract

Purpose: To present a revised interpretation of the work-up data that enabled diagnosis of preperimetric glaucoma (PPG) at the first examination.

Methods: a) Literature analysis on PPG; b) 6-year follow-up of a glaucoma-suspect patient.

Results: TWO NEW CONCEPTS MAY BE ADAPTED: (a) the objective finding of retinal nerve fiber layer (RNFL) thinning below the normal border in the opposing typical glaucoma locations, the inferior and superior quadrants, and in a non-diffuse pattern, appears asymptomatically and simultaneously only in glaucoma; and (b) the imaging-related RNFL thickness may be considered the reference glaucoma standard, whereas the suspicious early glaucomatous optic neuropathy, having a potential diagnostic inaccuracy, would serve as a complementary revealing finding. That approach enabled, in retrospect, a first-visit diagnosis of low-tension PPG in the patient. Diagnosis was confirmed after 6 years, when cecocentral scotoma and further RNFL thinning emerged despite treatment.

Conclusions: A revised approach enabled PPG diagnosis during the first visit.

Keywords: Preperimetric glaucoma; early glaucoma; low-tension glaucoma; optical coherence tomography; retinal nerve fiber layer..

Fig. (1)

Initial (in 2002) peripapillary retinal nerve fiber layer (RNFL) thickness as detected by the optical coherence tomography (OCT) in each eye of a 49-year-old patient with suspicious glaucomatous optic neuropathy (“glaucoma suspect”). Numeric comparison is made with the self-normative database software (bound in a double hump area).

Fig. (2)

(A) Top: The mean initial OCT RNFL examination of 5 scans is presented in clock-hours, quadrants, and graphically, in comparison with the OCT age-matched normative database software provided by the manufacturer (bound in yellow). The RNFL is thinner than the lower normal border in both the right (OD) and left eye (OS) superiorly, inferiorly and temporally. Bottom: Standard visual fields are normal. (B) Visual fields in September 2007. Cecocentral scotoma is evident bilaterally, more in the left eye. (C). Top: In May 2008, further thinning of the RNFL is detected in the inferior, superior and temporal quadrants of the right eye and in the superior quadrant of the left eye. Bottom: The cecocentral scotoma widened in the right eye and became non-specific and less distinct in the left eye.