The Port Harcourt Hospital Glaucoma Study

Aim: To study the prevalence and risk factors of glaucoma in a health setting.

Methods: The study was descriptive cross sectional study in which all the staff of the University of Port Harcourt Teaching Hospital were recruited through proper mobilization during world glaucoma week. Subjects’ intraocular pressures were assessed with Perkins applanation tonometer. Fundoscopy was done by direct ophthalmoscopy using Welch Allynes ophthalmoscope. The criteria for a case were subjects who had a typical glaucomatous cupping appearance of the optic nerve head with cup/disc (c/d) ratio >0.7 in one or both eyes with direct ophthalmoscopy and slit lamp biomicroscopy with +78D volk lens such as optic disc notching, violation of the ISNT rule with or without raised intraocular pressures, suspects were patients with c/d ratio of between 0.5-0.7 in one or both eyes or a difference of 0.2 or more between c/d and no demonstrable optic disc notching or violation of ISNT rule on slit lamp biomicroscopy with +78D volk lens and normal subjects had c/d 0.4 or less.

Results: A total of 2047 subjects were seen. This represented 81.88% of the staff strength of 2500. Among the subjects 171(8.4%) had glaucoma, 387(18.97%) were suspects while 1489(72.7%) were normal. 0.8% suspects were already blind while 7.2% had varying ranges of visual impairment. There was poor positive linear correlation between age and VCDR (Pearson’s correlation coefficient r=0.11, r2=0-01) and also poor linear correlation between age and IOP (Pearson’s correlation coefficient r=0.23, r2=0.06)

Conclusion: The prevalence of glaucoma at the University of Port Harcourt teaching hospital was 8.4%. 7.2% of the subjects already have visual impairment while 0.8% was already blind. This study also corroborates the factors that may cause late presentation since only 9.6% of the subjects had family history of glaucoma and as much as 90.6% had normal IOP.