Changes in anterior chamber depth following vitrectomy.

BACKGROUND: Anterior segment morphometry is crucial for ophthalmologists to understand the visual outcomes of cataract surgery, keratorefractive surgery, as well as some other anterior segment disorders. Previous reports in literature have shown that anterior chamber depth (ACD) may shift slightly after vitrectomy. This study aimed to characterize the shortterm changes in ACD in eyes after vitrectomy by means of A-scan ultrasound. METHODS: A prospective case series study was carried out on 29 eyes of 29 patients who underwent vitrectomy as the sole procedure. ACD was measured using A-scan ultrasound biometry shortly before vitrectomy and 1 week, 1 month, and 3 months after the surgery. Postoperative ACDs were compared with baseline. RESULTS: Twenty-nine patients (16 males and 13 females) were enrolled in the study, with mean age of (50 ± 11) (25-65) years. Twenty-three eyes of 23 patients were vitrectomized for vitreous hemorrhage (VH) and the other six were operated for idiopathic epiretinal membrane (ERM). The mean preoperative ACD of the VH eyes was (2.98 ± 0.38) mm. No significant difference was found between the ACD of the VH eyes and their fellow eyes (P = 0.058). The average preoperative ACD in the ERM eyes was (2.94 ± 0.31) mm, which was statistically deeper than that of their fellow eyes ((2.85 ± 0.28) mm, P = 0.008). No statistical difference was found in the postoperative average ACD of the VH eyes compared with baseline. In the ERM group, the postoperative ACD in the surgical eyes was still statistically deeper than the fellow eyes 1 week after surgery (P = 0.034). However, such statistical difference disappeared at 1 or 3 months postoperative (P = 0.186 and 0.682). CONCLUSIONS: ERM may induce deepening of the ACD, which can be recovered by uneventful vitrectomy. VH does not cause shift of ACD, neither does vitrectomy.

Treatment of retinal vein occlusion in rabbits with traditional Chinese medicine Fufang XueShuan Tong.

BACKGROUND: Retinal vein occlusion (RVO) is one of the most common causes of visual loss. Many approaches have been tried to treat central retinal vein occlusion (CRVO), and branch retinal vein occlusion (BRVO) with various results. However, there is no defined protocol and limited evidence to support the interventions currently used. The aim of this study was to assess the efficacy of the traditional Chinese medicine Fufang XueShuan Tong (FXST) in treating experimentally created RVO. METHODS: RVO model was first induced in forty-four pigmented rabbits through photocoagulation following injection of rose Bengal. The rabbits were divided into four groups based on the dose of FXST administered (212 mg/kg, 424 mg/kg, 848 mg/kg and control group). The rabbits were observed for four weeks after the procedure, using color fundus photography, fundus fluorescein angiography and electroretinogram examination. Vascular endothelial growth factor (VEGF), interleukin-6 and nitric oxide (NO) levels in the vitreous and histopathologic evaluation were monitored. RESULTS: The obstructed vessels in the treatment groups reopened or anastomosed faster than those in the control group (P < 0.05). The amplitude of maximum b wave and the oscillatory potential were significantly higher in the treatment groups than in the control group (P < 0.01). At both two weeks and four weeks, VEGF and IL-6 levels in the vitreous were significantly decreased in the treatment groups (P < 0.01), while NO levels were significantly elevated (P < 0.01). At the same time, histopathologic evaluation showed different retinal neuroepithelium structures in the different groups. Immunoreactivity of VEGF was greater in the control group than in the treatment groups. CONCLUSION: FXST was helpful in reconstructing retinal vessels in the RVO model, protecting retinal structures and improving visual function, and could inhibit the neovascular factor.