Visual Function Assessment Of Vitrectomy For Severe Proliferative Diabetic Retinopathy

Diabetic retinopathy is one of the common and serious diabetic microvascular complications and is also one of the major causes of bindness. serious impact on the visual function of patients and quality of life, late can lead to irreversible blindness, is the four major cause of blindness in Europe and the United States rank first or 2 of the eye. According to Prasad, a diabetic population of the latest survey of low vision low vision were significantly (<0.3) accounted for 2.84%, the best visual acuity≤0.05 persons (blind) accounted for 0.75%. Severe PDR is the end stage of diabetic retinopathy, retinal neovascularization due and fiber proliferation, leading to traction retinal detachment, and patients are frequently associated with optic nerve atrophy, extensive retinal vascular occlusion, invasion and macular traction or rhegmatogenous retina detachment and other serious complications are not allowed to light positioning. This group of cases are heavy and extremely complex disease, preoperative visual acuity worse, often accompanied by systemic multi-system organ dysfunction, whether surgical treatment can improve visual function after surgery, surgical treatment is worthwhile, is worth study. To study this issue seriously PDR after vitrectomy in patients with improvement of visual function and prognostic factors of visual function.macular disease,proliferative vitreoreti-nopathy,proliferative diabetic retinopathy and other complicated vitreoretinopathy. Vitrectomy which can remove the vitreous hemorrhage,relieve the traction on the retina caused by the proliferative membrane, restore the normal anatomy of the retina and maintain the integrity of the eyeball greatly reduces the blindness rate,therefore vitrectomy is the only effective method to the proliferative diabetic retinopathy.Accordingly it is very necessary to understand the impact of various factors on the postoperative visual acuity improvement.When vitrectomy is performed in early time,the retina is thick and flexible and the fibrovascular membranes adhere to the retina relatively loose so that it is easy to peel and sheer the fibrovascular membranes,therefor the postoperative complicatinos are reduced and it is conducive to the restoration of visual function.During the vitrectomy, clear removal of vitreous around the above sclerotic puncture ports to avoid forming ora serrata mutilation caused by intraocular microinstruments' repeated access to eyeball bringing out peripheral vitreous, extensive removal of the peripheral and post-capsular vitreous,gently peeling the fibrovascular membranes to avoid over-stretch, peeling the fibrovascular membranes as far as possible,properly dealing with the stump of fibrovascular membranes,and reasonably selecting vitreous substitutes can reduce postoperative complications and get a better visual prognosis.In short, during the clinical work we should closely observe the ocular fundus and when diabetic retinopathy develop into proliferative diabetic retinopathy we should determine the stage of diabetic retinopathy, master surgical indications and select reasonable time of operation in order to obtain a better visual prognosis.Objective:To evaluate the surgical effect of vitrectomy and different factors on the prognosis of proliferative diabetic retinopathy.Methods:The clinical datum of sixty-one eyes of 50 patients'who were cured by the same medical group in Department of ocular fundus disease in our hospital were studied from Oct,2007 to Jan,2008. The relationship between the postoperative visual acuity improvement rate and the factors were analyzed and summarized,such as the duration of diabetes, the preoperative stage of proliferative diabetic retinopathy, different vitreous substitutes preoperative PRP.Results:Duration of diabetes affects postoperative visual acuity improvement rate with no statistic difference(p=0.505>0.05);the preoperative stage of proliferative diabetic retinopathy affects postoperative visual acuity improvement rate with statistic difference(p=0.034< 0.05),and eyes of the IV PDR group tend to have better postoperative visual acuity improvement rate than the eyes of V PDR and VI PDR groups;the postoperative visual acuity improvement rate of eyes of non-tamponade group which mostly contain PDRIV eyes with light ocular fundus process is 90.9%, the postoperative visual acuity improvement rates of eyes of silicon-oil tamponade and inert-gas tamponade groups which mostly contain PDRV and PDRVI eyes with severe ocular fundus process are 63.6% and 53.6%:whether preoperative PRP is performed or not affects postoperative visual acuity improvement rate with no statistic difference(p=0.396>0.05)。Conclusions:1.Patients'visual acuity can be well improved by vitrectomy, which indicated that vitrectomy is an effective method to proliferative diabetic retinopathy nowadays.2. Duration of diabetes in this way is unrelated with postoperative visual acuity improvement rate in cases of this group.3. Eyes of the IV PDR group tend to have better postoperative visual acuity improvement rate than the eyes of V PDR and VI PDR groups:in addition eyes of non-tamponade group which mostly contain PDRIV eyes with light ocular fundus process have better postoperative visual acuity improvement rate.Therefor, vitrectomy should be performed in early time for patients with proliferative diabetic retinopathy to obtain a better visual prognosis.4. Whether preoperative PRP is performed or not has no relationship with postoperative visual acuity improvement rate.5.The augmentation of operative sample size is needed to explore roles of different factors in the visual acuity improvement rate after surgery for proliferative diabetic retinopathy.