Presumed hereditary retinal degenerations: Ibadan experience

Abstract

Retinitis pigmentosa (RP) is a hereditary retinal degenerative condition with no known treatment. Associated ocular conditions, such as cataract and glaucoma, when present further worsen vision, but these conditions are often treatable. There are, however, no known reports of cataract or glaucoma surgery in subjects with RP in Nigeria. This study describes the clinical presentation of RP, the prevalence of associated treatable disorders and the characteristics of patients with severe visual impairment and blindness. A retrospective review of 52 cases presumed and diagnosed to have. RP was performed on patients who presented at the Eye Clinic, University College Hospital, Ibadan over a three-year period. The cases were classified into clinical types; those with associated treatable eye conditions were identified and those with severe visual impairment and blindness were further evaluated. Retinitis pigmentosa was an uncommon clinical condition in patients who presented at the Eye Clinic being 0.69% (n = 52) of a total of 7,520 new outpatients recorded during a 3-year period. Typical RP were 44 in number representing 84.0% of these cases. Those diagnosed with very early onset RP, with severe visual impairment and nystagmus may have been congenital Leber's amaurosis. Retinitis pigmentosa with systemic features and atypical RP were uncommon. However, 34.5% had cataract (mostly posterior subcapsular cataract), while 11.4% had high intraocular pressure and these were mostly in couched eyes. Risk factors for severe visual disability and blindness were cataract, age and secondary glaucoma as a result of couching. Treatable ocular conditions associated with RP are not uncommon. RP patient tend to have cataract which if neglected may result in total blindness.