Objective To test the hypothesis that the macular pigment may be a marker of foveal cone function and consequently the structural integrity of foveal cones.Methods Sixteen patients (32 eyes) diagnosed to have Stargardt dystrophy and three patients with full thickness macular holes by clinical criteria were studied with a scanning laser ophthalmoscopy (SLO) comparing argon laser blue and infrared images for the presence or absence of macular pigment (MP) in the fovea. An C++ computer based program was used to evaluate the density of MP. Eyes were graded into three categories: those without foveal macular pigment, those with partial pigment and those with normal amounts of macular pigment. These categories were compared with visual acuity determined by the Snellen chart. Results Thirteen eyes with a visual acuity of 20/200 or worse had no macular pigment in the fovea. Eleven eyes with visual acuity of 20/40 or better had a normal amount of macular pigment in the fovea and 1 eye had partial macular pigment. Eleven eyes with partial macular pigment had intermediary acuity value.Conclusions Foveal macular pigment is closely related to foveal cone acuity and therefore may be a marker for the presence of foveal cones. Infrared light is a sensitive indicator of early macular diseases.(Chin J Ocul Fundus Dis，2003，19：201-268)
Objective To investigate the effects of phacoemulsification on macula in diabetics． Methods Thirty eyes of cataract in diabetics were chosen randomly for measurement of the thickness of fovea of retina using OCT before phacoemulsification and 1 month after surgery ． The other eyes in these patients and 30 eyes of cataract in nondiabetic pati ents with phacoemulsification were as control． Results In 30 eyes of diabetics with phacoemulsification, the mean fovea thickness were (148．5plusmn;27．7) mu;m preoperatively and (219．4plusmn;68．23) mu;m postoperatively, and the difference was significant (Plt;0．05)． In 30 eyes of diabetics without surgery, the mean foveal thickness were (147.4plusmn;27.5) mu;m preoperatively and (148.2plusmn;27.3) mu;m postoperatively and the difference was not significant (Pgt;0．05)． In 30 eyes of cataract in nondiabetic patients, the mean fovea thickness were (142．37plusmn;12．7) mu;m preoperatively and (151．9plusmn;23．7) mu;m postoperatively and the difference was not significant (Pgt;0．05)． In 30 eyes of diabetic s with phacoemulsification, 11 eyes had new macula edema after surgery and 3 eye s had significant retinal thickening． In 6 eyes with macular edema before surgery, the macular edema were aggravated in 3 eyes after surgery． The macular stru ctural changes were not found in two control groups． Conclusion The thickness of retina is inreased after phacoemulsification in deabetics,and morbidity and its severity of postopevative macular edema are increas ed as well． (Chin J Ocul Fundus Dis, 2001,17:175-177)
Purpose To observe the features of multi-focal electroretinogram (mERG) in Stargardtprime;s disease, and evaluate the validity of mE RG on diagnosis of this disease. Methods mERG had been recorded in 7 cases (14 eyes) of Stargardtprime;s disease with VERIS 4.0，and the findings were compared with normal individuals. Results The mERG were remarkably abnormal in all cases of the disease, as the amplitudes of N1 and P1 waves were seriously decreased and the latencies were prolonged in all the 6 regions (Plt;0.01). The degrees of the amplitude changes of N1, P1 waves were not the same in those areas,and the most decreased part was in fovea. The responses of N1, P1waves from the fovea of patients were about 19 and 10 percent respectively of which in controls. As the eccentricity enlarged, these differences had a tendency of reduction. The mERG topography of this disease could be divided to two types, i.e. central decreased and diffuse decreased types. Conclusion There are remarkably abnormalities on mERG in Stargardtprime;s disease,and the most damaged location of macular function is in fovea. (Chin J Ocul Fundus Dis, 2001,17:271-273)