Glaucoma screening in Western Cameroon.
OBJECTIVE
To quantify glaucoma-related parameters in a rural African region.


METHODS
In a population-based investigation, 635 persons in six villages underwent slit-lamp examination including investigation of the optic nerve head with a 90D lens and Goldmann applanation tonometry. The mean age of the persons was 49.4 +/- 19 years, minimum 5, maximum 90, median 52 years. The inferior, superior, nasal and temporal margin width of the optic nerve head (ONH) were estimated as fractions of the total disk diameter, thus allowing the evaluation of the horizontal and vertical cup-disk ratio (CDR), the ratio of the elliptical cup area to the total disk area (area CDR), and violations of the ISNT rule (Inferior>or=Superior>or=Nasal>or=Temporal ONH rim).


RESULTS
Area CDR significantly increased with age, on average from 0.1 in the youngest to 0.47 in the oldest person, corresponding to an increase of linear CDR from 0.32 to 0.68. The total fraction of eyes exceeding an area CDR of 0.5 (i.e. linear 0.7) was 13.4%. In addition, the intraocular pressure (IOP) increased on average from 14 mmHg in the youngest to 20 mmHg in the oldest persons, but nevertheless many high CDR values were found in eyes with normal to moderately elevated IOP. Violations of the ISNT rule were found in approximately 25% of the eyes. Application of a combination of glaucoma criteria as commonly used in literature resulted in a total prevalence of 18.7% of the screened persons, corresponding to a prevalence of 8.2% after age correction for the--on average--very young Cameroonian population.


CONCLUSIONS
Compared to Europe, glaucoma prevalence appears to be nearly an order of magnitude higher in this rural African population.
Preussner
Paul-Rolf
PR
University Eye Hospital, Langenbeckstr. 1, 55101 Mainz, Germany. pr.preussner@uni-mainz.de
Grossmann
Allegra
A
Ngounou
Faustin
F
Kouogan
Gabriel
G
Tamon
James
J
D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D002163:Cameroon / Q000453:epidemiology; D005902:Glaucoma, Open-Angle / Q000175:diagnosis* / Q000453:epidemiology*; D006801:Humans; D007429:Intraocular Pressure; D008875:Middle Aged; D009898:Optic Disk / Q000473:pathology; D015995:Prevalence; D012424:Rural Population / Q000706:statistics & numerical data; D014065:Tonometry, Ocular; D014792:Visual Acuity; D014794:Visual Fields; D055815:Young Adult
Surv Ophthalmol. 1989 Mar-Apr;33(5):331-7
2655138
Arch Ophthalmol. 2004 Jan;122(1):22-8
14718290
Invest Ophthalmol Vis Sci. 1999 Apr;40(5):849-57
10102281
Br J Ophthalmol. 1996 May;80(5):389-93
8695555
Invest Ophthalmol Vis Sci. 1988 Jul;29(7):1151-8
3417404
J Natl Med Assoc. 2006 Oct;98(10):1626-9
17052053
Br J Ophthalmol. 1995 Dec;79(12):1102-5
8562544
Am J Ophthalmol. 1965 Jan;59:8-12
14259946
Invest Ophthalmol Vis Sci. 1992 May;33(6):2012-8
1582806
Invest Ophthalmol Vis Sci. 2000 Jun;41(7):1764-73
10845597
Arch Ophthalmol. 1993 Sep;111(9):1263-9
8363470
JAMA. 1991 Jul 17;266(3):369-74
2056646
Br J Ophthalmol. 1998 Dec;82(12):1366-71
9930265
Arch Ophthalmol. 1994 Jun;112(6):821-9
8002842
Br J Ophthalmol. 2002 Nov;86(11):1232-5
12386076
Br J Ophthalmol. 1998 Apr;82(4):352-61
9640180
Arch Ophthalmol. 2006 Nov;124(11):1579-83
17102005
Bull World Health Organ. 2004 Nov;82(11):844-51
15640920