Objective To investigate the early influences of laser photocoagulation on retinal function in diabetic retinopathy(DR)． Methods The multifocal electroretinograms (MERG) of 30 eyes with DR (phase Ⅲ～Ⅳ) were tested with visual evoked response image system IV b efore,and the 3rd day and the 7th day after laser photocoagulation． Results Three days after photocoagulation, the latency of N1 prolonged in the central macula 5deg; area and superionasal quadrant．Th e response densities of N1,P1 and N2 markedly reduced, and most significant changes occurred in the central macula 5deg; area and then in the central 10deg;area． There were also differences in the changes of the amplitude of N1 and P1 in diff erent quadrants ．The changes of visual acuity were positively related to the de crease of amplitudes of N1,P1 and N2 in the macula． Conclusion The reduction of response densities in MERG reveals functional damage in diabetic retina occurring early after photocoagulation．The functional damage in macula induced indirectly by photocoagulation may explain the reduction of visual acuity after panretinal photocoagulation in some degree． (Chin J Ocul Fundus Dis, 2001,17:181-183)
ObjectiveTo evaluate the prognosis of photocoagulation and (or) cryotherapy for prethreshold type 1 and threshold disease of retinopathy of prematurity (ROP).MethodsThe data of 29 eyes of 15 infants who were diagnosed as with prethreshold type 1 or threshold disease of ROP from Jan 30th, 2003 to Jan 13th, 2005 were retrospectively analysed. Pre- and post-operative conditions of ROP were compared in the follow up. Any related local and systemic complications were recorded.ResultsIn 29 eyes which had undergone photocoagulation and (or) cryotherapy, ROP regressed completely in 19 (65.5%), remained dragged retina was found in 7 (24.1%), and retinal detachment was seen in 3 (103%). ROP regressed completely in 12 eyes (41.4%) after the initial treatment and in 7 eyes (24.1%) after the secondary treatment. During the treatment, temporary corneal haze was found in 2 eyes, vitreous hemorrhage occurred in 1 eye, and inadvertent photocoagulation at macular area happened in 1 eye. No systemic complications were found in all cases.ConclusionTimely treatment of photocoagulation and (or) cryotherapy for prethreshold type 1 and threshold disease of ROP may lead to famous prognosis.(Chin J Ocul Fundus Dis,2005,21:278-281)
Objective To evaluate the clinical effect of percutaneous laser disc decompression (PLDD) in the treatment of cervical disc herniation. Methods From March 2003 to December 2005, 47 patients with cervical disc herniation(96 cervical disc) were treated with PLDD. There were 25 males and 22 females with an average age of 56 years, ranging from 37 to72 years. The lesion were located at the levels of C3,4 in 20 discs, C4,5 in 27 discs, C5,6 in 31 discs, C6,7 in 18 discs. The laser fiber was introduced into the center of the herniated disc space by percutaneous puncture from anterior neck surface under fluoroscopic guidance. Laser reduced the intradisc pressure through the vaporization of disc nucleu. The adopted laser was semiconducted with a wavelength of 810 nm. Each laser output power was15 W with 1 s emission and 2 s interval. The total laser output power was decided depending on the degenerative degree of the disc and the reactive process of heat, ranging from 300 to 1 000 J.Results Of 47 patients,42 were followed up for 3 to 31 months (mean 13 months). The clinical evaluation was classified as excellent in 18 cases (42.9%), good in 14 cases (33.3%), fair in 6 cases (14.3%) and poor in 4 cases (9.5%). The general response rate was 90.5%. The excellent and good rate was 76.2%. No complications occurred. Conclusion PLDD can relieve the symptoms and signs of patients suffering from cervical disc herniation with less complication. The manipulation of PLDD is easy, safe and mini-invasive.