Abstract
Purpose: :
To determine which factors contribute to long-term stability in low-pressure glaucoma (LPG) patients.
Methods: :
Of 52 charts classified as having LPG, 53 eyes of 27 patients (mean age 74 years; 67% female; mean follow-up 9 years) met eligibility criteria and were included in the study. Patient records were evaluated retrospectively for history of hypertension, family history of glaucoma (FH), mean intraocular pressure (IOP), treatment with drops, laser or surgery, and any incidence of progression. Eligibility criteria were: minimum follow-up 8 years, > 20 years of age, confirmed LPG with visual field loss, DDLS > 4, all IOPs < 21 mmHg and open angle on gonioscopy. Patients with history of ocular trauma, uveitis, optic neuropathy or any other form of glaucoma were excluded. Standard Humphrey 24-2 visual fields (VFs) were considered reliable if they had fixation losses < 25%, false positive and false negative rates < 33%. Criteria for progression were defined as a worsening of the optic nerve in at least three consecutive disc drawings as judged by a glaucoma expert, with corresponding worsening of at least three consecutive VFs as defined by the following criteria: (1) deepening of an existing scotoma: two or more points ≥ 10 dB poorer in the same locations as the baseline scotoma, (2) expansion of an existing scotoma: two or more points ≥ 10 dB poorer adjacent to the baseline scotoma, or (3) new scotoma: two or more adjacent points not within or adjacent to baseline scotoma ≥ 5 dB poorer, or one point within the central 10 degrees ≥ 10 dB poorer. When both disc and VF worsened that eye was considered worse, and when neither worsened that eye was considered stable.
Results: :
During the follow-up period 33 eyes (62%) were stable, 9 eyes (17%) worsened, and 11 eyes (21%) had unrelated VF and disc changes. Of the 33 eyes that were stable, 6 (18%) were stable on treatment with drops only. In the remaining stable eyes, additional treatments included laser (39%), surgery (30%), both laser and surgery (12%). Of patients with FH, 8 (57%) were stable and 6 (43%) worsened in one or both eyes. Of patients without FH, 12 (92%) were stable in one or both eyes and none got worse.
Conclusions: :
Most eyes (62%) were stable in long-term observation. There was a significant correlation between the the absence of FH and stability (p<0.01). There were no significant correlations between type of treatment, mean IOP, or history of hypertension and stability.
Keywords: clinical (human) or epidemiologic studies: risk factor assessment • clinical (human) or epidemiologic studies: outcomes/complications