Immunohistochemical analysis of vascular endothelial growth factor (VEGF) and p53 expression in pterygium from Tunisian patients.

A pterygium is characterized by abnormal fibrovascular corneoconjunctival tissue. A number of investigations have attempted to elucidate this incompletely understood pathology. Since vascular endothelial growth factor (VEGF) and p53 are known to participate in tumor vascularization, our purpose was to study VEGF and p53 expression in active primary and recurrent pterygium from Tunisian patients. To this end, 15 cases of active primary pterygium and five cases of recurrent pterygium from Tunisia were studied by immunohistochemistry. Antibodies raised against VEGF and p53 were used to analyze the distribution and expression of these markers in pterygium and normal human conjunctiva were used as negative control. VEGF and p53 proteins were found in all cases of primary pterygium in epithelial, fibroblast and vascular endothelial cells. Active primary and recurrent pterygium have different patterns of expression. In primary pterygium, an important variability of p53 and VEGF expression was observed. However, in recurrent pterygium, p53 immunoreactivity was weak to moderate, whereas VEGF immunoreactivity was strong. In normal human conjunctiva, VEGF and p53 expression was weak to negative. The overexpression of VEGF in active primary and recurrent pterygium suggests that angiogenesis may play a role in pterygium pathogenesis and the expression of p53 in active primary pterygium, which might be associated with its mutated form, supports the hypothesis that actinic radiation may be involved in the genesis of pterygium. Thus, VEGF and p53 may be useful biomarkers for understanding the physiopathology of pterygium.

[Retinal vasculitis. Epidemiological, clinical and etiological features]. / Les vascularites rétiniennes: profils épidémiologiques, cliniques et étiologiques.

PURPOSE: To study the epidemiological and clinical features of noninfectious retinal vasculitis (NIRV). METHODS: We analyzed 128 consecutive patients with NIRV, collected over 15 years (1993-2007) in an ophthalmological reference university hospital in Tunis, Tunisia. Data were analyzed regarding associated systemic disease, ocular syndromes, anatomic features (type and topography of vessel and type of capillaropathy), age and sex. The results of the etiologic work-up were based on the Levy-Clarke and Perez classification. RESULTS: A total of 240 cases of NIRV (128 patients) were collected (mean age: 32; sex ratio: 2.6). It was bilateral in 93.7% of cases. The mean visual acuity (VA) was 20/50 (range: 20/800-20/20). NIRV was mainly venous (84.1%), diffuse (57%), with a mixed capillaropathy (40.2%). There were complications in 56.25% of the cases, mainly macular edema (48.1%), vascular occlusion (25.9%), optic atrophy (22.2%) and cataract (19.2%). NIRV was idiopathic in 15.6% of the cases, characterized by a predominance of young subjects (mean: 38 years old), males (sex ratio: 4), VA at 20/25, and edematous periphlebitis in 100% of cases. There were ocular disorders in 12.5% of the cases and systemic disease in 72% of the cases, with a predominance of Behçet disease (BD): 53.9% of all patients and 81% of systemic disease with predominant venous features. In 48.3% of cases, VA was less than 20/200, due to BD in 48% of the cases. CONCLUSION: In NIRV, the etiologic work-up is oriented on anatomic presentation, based on fluorescein retinal angiography, and requires an interdisciplinary approach. In young adults with retinal phlebitis, BD is suggested first.

Immunohistochemical analysis of cellular adhesion molecules (ICAM-1, VCAM-1) and VEGF in fibrovascular membranes of patients with proliferative diabetic retinopathy: preliminary study.

PURPOSE: Diabetic fibrovascular membranes are the main pathological changes of proliferative diabetic retinopathy that can cause serious complications leading to blindness. Since the mechanism of fibrovascular membrane development is still unknown, the aim of our study was to identify potential biomarkers for this pathology. To this end, we analyzed the simultaneous expression of ICAM-1, VCAM-1 and VEGF within tissues of diabetic fibrovascular membranes. PATIENTS AND METHODS: Fibrovascular membranes were taken from nine diabetic patients with proliferative diabetic retinopathy. The fibrovascular membrane specimens were analyzed by immunohistochemistry to determine ICAM-1, VCAM-1 and VEGF expression. Controls were collected on nine normal conjunctivas removed during senile cataract surgery. RESULTS: Coexpression of ICAM-1, VCAM-1 and VEGF was found in most of the diabetic fibrovascular membranes studied. Thus, ICAM-1 was positive in eight of nine membranes (82%), VCAM-1 in seven of nine membranes (78%) and VEGF in all the membranes. CONCLUSIONS: The substantial overexpression of adhesion molecules ICAM-1, VCAM-1 and of VEGF suggests that these molecules might contribute to the development of fibrovascular membranes in patients with proliferative diabetic retinopathy, and that they could constitute suitable markers of this pathology.

Frequency, characteristics, and risk factors of late recurrence of retinal detachment.

PURPOSE: To evaluate the frequency, characteristics, causes, and risk factors of late recurrent retinal detachments (LRRD). METHODS: The authors retrospectively analyzed 445 eyes operated consecutively for rhegmatogenous retinal detachment between 1990 and 2003 by the same surgeon. Only eyes with complete reattachment after a minimum follow-up of 6 months were included. The authors defined LRRD as detachment occurring at least 6 months after a complete retinal reattachment. RESULTS: Nine eyes had a LRRD (2.02%). Mean age was 52.55 years. Six eyes had scleral buckle procedure and three eyes had vitrectomy silicone oil injection then silicone oil removal. LRRD occurred after an average period of 54 months. During follow-up two patients had a removal of extrusion of scleral buckling material. New or reopened breaks were associated with LRRD in all eyes. Endo-ocular surgery was carried out in seven eyes. The retinal reattachment was achieved in the seven eyes. Final visual acuity ranged from 20/400 to 20/60 after an average follow-up of 37.8 months. Relation between aphakic eyes (and more generally nonphakic eyes) and LRRD was close to significant value (p=0.05). LRRD was statistically independent (p>0.05) of myopia, preoperative pseudophakia, vitrectomy for initial detachment, scleral buckle removal, and cataract surgery after reattachment. CONCLUSIONS: LRRD were rare. Most of them were due to a retinal break. This break can be a new break, or reopened break especially after removal of scleral buckle material. Vitreous traction, at the vitreous base, seemed to be the cause of these breaks.

[Familial exudative vitreoretinopathy associated with persistence of hyaloid artery]. / Association d'une vitréo-rétinopathie familiale exsudative à une persistance de l'artère hyaloïdienne.

Familial exudative vitreoretinopathy (FEVR) is a well-defined inherited disorder of retinal vessel development. Association of FEVR with other congenital ocular diseases has already been described. We report the first clinical case of FEVR associated with hyaloid artery persistence. An 18-year-old Tunisian woman and four members of her family (mother, two brothers, and sister) presented signs of FEVR. Examination of this patient also revealed functional hyaloid artery persistence in her right eye. These two disorders have many common aspects in their pathological process, in particular vascular endothelial growth factor expression, which can explain this association.

Effect of pterygium surgery on corneal topography.

PURPOSE: To evaluate the effect of successful pterygium surgery on corneal topography. METHODS: Computerized corneal topography was performed on 20 eyes with pterygium before and 3 months after successful excision and limbo-conjunctival autograft surgery. Corneal shape, corneal spherical power, simulated keratometric astigmatism, surface regularity index (SRI), and surface asymmetry index (SAI) were assessed before and after surgery. Pre- and postoperative uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), and manifest refraction spherical equivalent (MRSE) were also evaluated. RESULTS: Changes in corneal shape were mainly a decrease in midline corneal flattening. Corneal spherical power was 41.65+/-3.29 diopters (D) (mean +/- SD) preoperatively and 44.58+/-1.55 D postoperatively (p=0.04). Simulated keratometric astigmatism was 5.47+/-3.45 D preoperatively and 1.79+/-1.52 D postoperatively (p=0.0005). SRI was 1.39+/-0.93 preoperatively and 1.10+/-0.57 postoperatively (p=0.03). SAI was 1.17+/-1.09 preoperatively and 0.75+/-0.73 postoperatively (p=0.02). UCVA was 0.31+/-0.33 preoperatively and 0.52+/-0.32 postoperatively (p=0.04). BSCVA was 0.73+/-0.20 preoperatively and 0.89+/-0.16 postoperatively (p=0.008). MRSE was -0.54+/-3.29 D preoperatively and -1.30+/-3.05 D postoperatively (p=0.45). CONCLUSIONS: Corneal topographic changes caused by the pterygium are almost reversible after surgical treatment. Successful pterygium surgery significantly reduces topographic astigmatism, SRI, SAI, and corneal flattening. However, precise prediction of these refractive changes is not always accurate.