Positioning of a morbidly obese patient during retinal surgery

A body mass index (BMI) ?35 kg/m2 is classified as obese, and a BMI ?40 kg/m2 is classified as morbidly obese. Obese people are at a higher risk for developing cardiovascular complications like ischemic heart diseases, congestive cardiac failure, hypertension, type 2 diabetes mellitus and obstructive sleep apnea (OSA) among other health issues. Central obesity can also increase the pleural pressure and cardiac filling pressures, thus increasing the intracranial (ICP) and intraocular pressure (IOP). These clinical co-morbidities can make retina surgeries, which require patient in supine position for 45-90 minutes, a challenging task. We present our experience in the intraoperative positioning of such a patient who underwent surgery for retinal detachment.

Vitreoretinal surgery using the 25G transconjunctival sutureless vitrectomy system under topical anesthesia / 中华眼底病杂志

Objective To evaluate the indications, effectiveness and complications of vitreoretinal surgery using the 25G transconjunctival sutureless vitrectomy system (TSV25G) under the topical anesthesia. Methods The clinical and follow-up data of 22 eyes of 22 patients undergone vitreo-retinal surgery using TSV25G under the topical anesthesia were retrospectively analyzed. All of the patients were monocular sickened, including idiopathic macular hole in 10 eyes, idiopathic macular pucker in 6, vitreoretinal traction syndrome in 4, and vitreous hemorrhage associated with branch retinal vein occlusion in 2. Peeling of epiretinal membrane and/or internal limiting membrane, intraocular laser coagulation, air-fluid exchange and tamponiding of C 3F 8 were performed according to the condition of diseases. The postoperative follow-up was 1-11 months, with the mean duration of 6.4 months. The effect of analgesia, cooperation with the patients, operative effect and complications in and after the surgery were observed. Results The operations finished successfully in all of the eyes under the topical anesthesia. The operation duration ranged from 20 to 25 minutes with average of 22 minutes. The patients cooperated with the doctor well without any discomfort. Two days after the surgery, edema of the wounded conjunctiva was found, and recovered 7 days later. A light pigment dot on the surface of the sclera could be seen at the first month. The complications included transient increasing of intraocular pressure in 2 eyes, feather-like opacity of lens in 5 eyes, vitreous hemorrhage in 1 eye, and air-bleb under conjunctiva in 2 eyes. No other complications related with the cut were found. The macular hole closed in 9 eyes with idiopathic macular hole, and the other 1 had the smaller but not closed hole. Idiopathic macular pucker, vitreoretinal traction syndrome, and vitreous hemorrhage associated with branch retinal vein occlusion were cured successfully. Conclusions Vitreoretinal surgery using the TSV25G under the topical anesthesia has many advantages such as simple procedure, short operation time, micro-invasion, less complications and rapid revovery, and mainly serves simple manipulation in some simple diseases such as idiopathic macular hole, vitreo-retinal traction syndrome, and simple hemorrhage.

Experimental study of limited macular translocation / 中华眼底病杂志

Objective By using a newly developed animal model of limited macular translocation (LMT) in rabbit eyes, to explore the complications,indications and predictability of LMT. Methods LMT models were performed in 15 rabbit eyes, and were divided into 4.5 mm group and 3.5 mm group by the length of scleral shortening.The effect of retinal translocation (distance and direction) and its complications were analyzed. In a separated group, postoperative corneal astigmatism was studied after release of scleral shortening suture 1 month after LMT. In order to study the impact of neuroretina retinal pigment epithelium (RPE) adhesion on LMT, retinas and choroids in 4 pigmented rabbit eyes were pretreated with photocoagulation. Results Success rate of LMT was 86 7%. In these cases, retinal translocations were achieved [(distance of 610 to 2 690 ?m, [AKx-]?s =(1 395?636) ?m; translocation angle ? of 10 38?, ?s =(22.7?8.3) ?]. The difference in scleral shortening between 4.5 mm and 3.5 mm groups did not significantly influence the final translocation. Major complications of LMT included intraocular bleeding, retinal break, and corneal astigmatism. Release of scleral shortening suture reduced corneal astigmatism and made it more regular, meanwhile, retinal translocation did not regress. The neuroretina RPE adhesion induced by retinal photocoagulation made neuroretinal hydrodissection difficult, and led to retinal break readily. . The difference in scleral shortening between 4.5 mm and 3.5 mm groups did not significantly influence the final translocation. Major complications of LMT included intraocular bleeding, retinal break, and corneal astigmatism. Release of scleral shortening suture reduced corneal astigmatism and made it more regular, meanwhile, retinal translocation did not regress. The neuroretina RPE adhesion induced by retinal photocoagulation made neuroretinal hydrodissection difficult, and led to retinal break readily. Conclusion Sufficient LMT models in rabbit eye were obtained with few postoperative complications. Direction of retinal translocation is an important factor influencing the effect of LMT, except for distance. Release of scleral shortening suture can effectively reduce corneal astigmatism without causing regression of retinal translocation. For the patients with a history of macular or para macular photocoagulation, LMT should be performed carefully.

Experimental research of intraocular retention of domestic perfluorocarbon liquid / 中华眼底病杂志

Objective To investigate the effect of long-term intraocular retention of domestic perfluorocarbon liquid (PFCL) on morphology and histology of ocular tissues. Methods A total of 18 New-Zealand rabbits were randomly divided into 3 experimental groups, whose left eyes underwent intraocular injection with 0.3, 0.6, and 1.0 ml PFCL, respectively. All of the right eyes of the rabbits were in the control group. The morphological, electrophysiological and histological changes of the ocular tissue were observed 4, 8, and 12 weeks after the injection. Results No clinically significant retinopathy but only mild morphological changes were found in group 1 and 2, while obvious morphological and histological changes were found in group 3. Mild morphological and histological changes were found in all of the rabbits 4-8 weeks after the injection while significant ones were found 8-12 weeks after the injection. The results of electroretinography indicated a statistically significant decline of amplitude of b wave in group 3. Conclusions Long-term intraocular retention of few PFCL may cause mild histological changes but not affect the clinical function. Plentiful PFCL remains in eyes may lead to toxic reaction to the ocular tissue.

THE USE OF DOMESTIC PERFLUOROTRIBUTYLAMINE FOR THE MANAGE-MENT OF GIANT RETINAL TEARS / 中华眼底病杂志

We used domestic perfluorotributylamine to treat 21 eyes with giant retinal tears, including 5 rhegmatogenous retinal detachment with folded and fixed flap and 16 giant retinal tears resulting from retinotomy and retinectomy due to complicated retinal detachment. The success rate of retinal reattachment was over 95%, with no serious side effects. The activities and complications of perfluorotributylamine in the mangement of giant retinal tears were discussed.

Relaxing retinotomy for the treatment of perforating traction retinal detachment / 中华眼底病杂志

Objective To explore the therapeutic value and effects of relaxing retinotomy for perforating traction retinal detachment(PTRD). Method A retrospective survey was done in 21 patinets (21 eyes) with PTRD who underwent vitrectomy combined with relaxing retinotomy in our hospital from 1998 to 2001. Results The retinae were completely reattached in all 21 cases. The visual acuity of 12 patients (57%) was counting finger, and the best visual acuity was 0.05. Among the 18 patients who were followed up for 6 to 25 months, 14(77.8%) remained retinal reattachment. Conclusions Relaxing retinotomy is effective for anatomic reattachment of PTRD, especially to the patients with retinal incarceration and severe proliferative vitreoretinopathy.

Factors influencing the therapeutic efficacy of Argon laser photocoagulation on proliferative diabetic retinopathy / 眼科

108 eyes of proliferative diabetic retinopathy were treated with Argon laser panretinal photocoagulation. Three months after treatment, The systemic and local factors influencing the therapeutic effecacy were treated by "stepwise discriminations analysis" to tind that the relevant factors included the severity and location of neovascularization and the total doses of laser irradiation. For eyes with papillar or mutiple and low dosage of laser irradiation, the therapeutic efficacy was poor.

Laser photocoagulation for the treatment of retinal periphlebitis / 眼科

39 cases (49 eyes) with retinal periphlebitis (Eales' disease) were treated by laser photocoagulation and followed up for 3～64 months, averaging 17 months. The visual acuity improved in 29 eyes (59.1％), remained unaltered 15 eyes (30.7％),and diminished in 5 eyes (10.2％). The results showed that laser photocoagulation was effective and safe for the treatment of Eales' disease. The importance of early diagnosis, early treatment, periodical follow-up and the use of corticosteroids were discussed.

Laser panretinal photocoagulation for the treatment of diabetic retinopathy / 眼科

213 eyes (138 cases)with diabetic retinopathy (DR) were treated with laser panretinal photoeoagulation(PRP)and followed up for 3～72 months, during which time the visual acuity improved in 70 eyes (32.9％), remained unaltered in 77 eyes(36.1％), and diminished in 66 eyes (31％). The results indicated that PRP for the treatment of DR was effective and safe, with few complications. Factors affecting performance of the technique and visual prognosis were discussed.