a.t . , a 43-year - old nigerian lady , presented to the eye clinic of the university college hospital , ibadan with gradual blurring of vision in both eyes for 4 years . ocular examination showed unaided visual acuity of 6/12 ou corrected to 6/9 in both eyes . dilated fundoscopy showed a well circumscribed cystic fovea lesion with a fluid level and an atrophic center in the right eye , while the left eye showed a scar in the macula ( fig . 1 and fig . the patient was prescribed with spectacles , counseled and placed on close observation with amslers grid for the development of choroidal neovascular membrane that will require urgent treatment . this is probably the first case of best macular dystrophy to be reported in ibadan , nigeria and possibly sub - saharan africa to the best of the author 's knowledge . it has also been reported in caucasians and asians , the other cases seen in african americans were associated with sickle cell trait . the pathophysiology of best 's disease is explained by abnormality in the retinal pigment epithelium ( rpe ) with resultant abnormal ionic transport leading to the accumulation of lipofuscin in the rpe cells and sub - rpe space in the macular area . the vitelliruptive stage may herald visual deterioration which becomes worse in the atrophic stage due to the presence of choroidal neovascular membrane . our patient presented with the early stages of the disease , hence the good visual acuity . the patient will be under observation and follow - up so as to detect changes amenable to treatment . choroidal neovascular membrane ( cnvm ) from best 's disease has been reported to respond well to intravitreal antivegf [ 7 , 8 ] . fundus flourescein angiography is essential in confirming the presence of cnvm and should be done when patient presents with sudden deterioration in vision . if a cnvm develops , then a corresponding area of hyperfluorescence with leakage will be found . since the disease is an autosomal dominant disorder , other family members will benefit from regular fundus examinations , and amslers grid is a valuable tool for monitoring central vision . an electrophysiologic test such as electrooculogram ( eog ) is specific for confirming the presence of the disease in relatives even in the absence of clinical signs and symptoms . a severe decrease occurs in light response , reflected by an arden ( light - peak / dark - trough ) ratio of 1.11.5 ( the normal arden ratio is 1.8 ) . the full - field electroretinogram ( erg ) result is normal in best 's disease . a focal erg or multifocal erg , concentrating on macular function , reveals abnormal function corresponding to the area of anatomical disruption . the pathophysiology of best 's disease is explained by abnormality in the retinal pigment epithelium ( rpe ) with resultant abnormal ionic transport leading to the accumulation of lipofuscin in the rpe cells and sub - rpe space in the macular area . the vitelliruptive stage may herald visual deterioration which becomes worse in the atrophic stage due to the presence of choroidal neovascular membrane . our patient presented with the early stages of the disease , hence the good visual acuity . the patient will be under observation and follow - up so as to detect changes amenable to treatment . choroidal neovascular membrane ( cnvm ) from best 's disease has been reported to respond well to intravitreal antivegf [ 7 , 8 ] . fundus flourescein angiography is essential in confirming the presence of cnvm and should be done when patient presents with sudden deterioration in vision . if a cnvm develops , then a corresponding area of hyperfluorescence with leakage will be found . since the disease is an autosomal dominant disorder , other family members will benefit from regular fundus examinations , and amslers grid is a valuable tool for monitoring central vision . an electrophysiologic test such as electrooculogram ( eog ) is specific for confirming the presence of the disease in relatives even in the absence of clinical signs and symptoms . a severe decrease occurs in light response , reflected by an arden ( light - peak / dark - trough ) ratio of 1.11.5 ( the normal arden ratio is 1.8 ) . the full - field electroretinogram ( erg ) result is normal in best 's disease . a focal erg or multifocal erg , concentrating on macular function , reveals abnormal function corresponding to the area of anatomical disruption . this is a report of best macular dystrophy in ibadan , sub - saharan africa .