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A letter to the editor is presented which discusses the immunohistochemical analysis of internal limiting membrane (ILM) using confocal microscopy in stage four idiopathic macular hole surgery.

A letter to the editor is presented which discusses a case of a 42-year-old Sudanese woman with systemic lupus erythematosus who subsequently sustained a combine bilateral central retinal artery and vein occlusion which resulted to visual loss.

Introduction: The aim of this study was to evaluate the incidence of pseudophakic retinal detachment (RD) recurrence after primary vitrectomy., Patients and Methods: This was a prospective nonrandomized consecutive case series study, evaluating two series presenting to our clinic with pseudophakic RD from 1998 to 2004 (103 eyes of 97 patients). The study included 24 consecutive pseudophakic eyes treated with gas vitrectomy surgery with placement of an encircling band from January 1998 to December 2000 (group A) and 79 consecutive pseudophakic eyes treated with gas vitrectomy surgery with no encircling band from January 2001 to December 2004 (group B). Pre- and postoperative characteristics were analyzed in both groups. In the cases of postoperative RD recurrence, we particularly analyzed the pre- and postoperative risk factors, as well as the anatomic and functional outcome., Results: Visual acuity improved in 74/103 (71.8%) eyes from both groups postoperatively. Recurrence of RD after primary vitrectomy occurred in eight of 103 (7.8%) eyes in both groups. More specifically, two of 24 (8.3%) eyes in group A and six of 79 (7.6%) eyes in group B presented a recurrence after gas vitrectomy with encircling band and gas vitrectomy alone, respectively. Among these eight eyes, four eyes (50%) presented proliferative vitreoretinopathy (PVR) at the time of initial vitrectomy, while all eyes presented PVR at the time of recurrence (one grade B, seven grade C). These eyes required two additional interventions on average. Five eyes (62.5%) required silicone-oil tamponade for a good anatomic reapplication., Discussion: These results show that recurrence after primary vitrectomy for pseudophakic RD is most often related to the presence of PVR before or after the first intervention. This series reports a success rate of 91.7% and 92.4%, respectively, for group A and B, thus demonstrating the efficacy of vitrectomy in the treatment of pseudophakic RD. This study also shows a nonsignificant difference in the recurrence rate among patients treated by gas vitrectomy and those undergoing gas vitrectomy in association with encircling band placement, which raises the question of the usefulness of an additional encircling band in pseudophakic RD.

Background: 360 degrees encirclement for rhegmatogenous retinal detachment (RD) was introduced over 50 years ago as a method for closing retinal breaks and relieving vitreous traction. In the absence of acknowledged guidelines, current usage varies widely., Patients and Methods: All 360 degrees encircling bands for RDs performed between 1999 and 2004 were reviewed. Encircling procedures for phakic and recurrent RDs were analysed., Results: 41 encircling bands for RD were identified from the records of 875 RD cases. Median follow-up was 6 months (range: 1 - 36). Male patients accounted for 58.5 % of the procedures. Mean age was 51.51 +/- 15.97 years. 37/41 phakic and 18/41 recurrent RDs were encircled. RD recurrence in encircled eyes occurred in 42 % of phakic eyes and in 33 % of eyes re-operated for recurrent RD. At the time of recurrence, proliferative vitreoretinopathy (PVR) was present in 41.6 % of phakic eyes, and 66 % of recurrent RD eyes. Preoperative visual acuity (VA) was 0.26 and post-operative VA 0.34. Post-operative complications due to the encirclement included pain in 4 eyes, scleral abscess in 2 eyes and scleral necrosis in 1 eye., Conclusion: This small retrospective review highlights the multiple indications for encircling bands including PVR, inferior breaks, multiple breaks and myopia. High overall recurrence rate (34 %) reflects the selection bias of this procedure for severe disease in our series. There is currently no consensus on the use of this technique in the management of RD.

Background: This study aims to evaluate the outcome of primary vitrectomy/gas for pseudophakic retinal detachment (RD) located inferiorly or associated to inferior breaks., Patients and Methods: We performed a retrospective, non-randomised study comprising 18 pseudophakic RD eyes with inferior RD (group A) and 19 pseudophakic RD eyes with inferior breaks (group B) treated with primary vitrectomy and gas tamponade (SF (6) 20 %). Pre- and postoperative characteristics were analysed, focusing on RD recurrences., Results: In group A, RD recurred in 2/18 eyes (11 %) and was associated to proliferative vitreoretinopathy (PVR) both at first intervention and on recurrence. In group B, RD recurred in 4/19 eyes (21 %). One eye presented PVR at first intervention and all at re-intervention. Anatomic reapplication was achieved after second vitrectomy/gas in 2/4 eyes of group B, whereas long-term silicon oil tamponade was needed in 2 eyes of each group., Conclusions: This series shows a high success rate of primary vitrectomy/gas in pseudophakic RD patients with inferior RD or detachment associated to inferior breaks. Recurrences after vitrectomy are most often related to the presence of PVR.

Introduction: Panretinal photocoagulation proved to be effective in preventing complications related to vasoproliferative diabetic retinopathy. Surgery is most often a last resort in cases of recurrent or persistent vitreous hemorrhage or retinal detachment. The aim of our study is to point out that eyes requiring surgery for complications related to vasoproliferative diabetic retinopathy are often insufficiently photocoagulated., Patients and Methods: Retrospective analysis of operating protocols and surgical results for a series of 39 eyes of 36 patients with complications of vasoproliferative diabetic retinopathy., Results: The mean age at the intervention was 57 years. Eighty-five percent of the eyes had a vitreous hemorrhage, 17% a retinal detachment. Eighty-five percent of the eyes had undergone a partial retinal photocoagulation before surgery. All eyes underwent a vitrectomy with segmentation of fibrovascular membranes. In 85% of the eyes studied, endolaser photocoagulation was necessary, sometimes even in the mid-periphery. After 39+/-26 months of postoperative follow-up, 97% of eyes showed improvement of the anatomical state of the retina and improvement or stabilization of visual acuity., Conclusion: Our results confirm the benefit of vitreoretinal surgery in complications related to vasoproliferative diabetic retinopathy. Moreover, it should be emphasized that complications requiring surgery often result from incomplete preoperative photocoagulation. To be effective, photocoagulation has to destroy more than 35% and up to 50% of photoreceptors. An intraoperative laser extension can reduce the risk of regrowth of fibrovascular membranes.

Background: The purpose of our study was to evaluate the variations of the optic disc PO (2) during normoxia and hyperoxia (100 % O (2)), before and after intravenous administration of acetazolamide., Material and Methods: PO (2) measurements were obtained at intervascular areas of the optic disc in 11 anaesthetized miniature pigs using oxygen-sensitive microelectrodes introduced through the vitreous cavity by a micromanipulator. PO (2) was measured continuously during 10 minutes under systemic normoxia and systemic hyperoxia. Oxygen measurements were repeated under these conditions after intravenous injection of acetazolamide (bolus of 500 mg) in 8 animals., Results: In systemic hyperoxia, the optic disc PO (2) increased moderately (DeltaPO (2) = 4.7 +/- 2.5 mmHg; p < 0.001; n = 11) in parallel with systemic PaO (2). Acetazolamide led to a slow and progressive increase in the optic disc PO (2) (DeltaPO (2) = 2.1 +/- 1.7 mmHg; p > 0.1; n = 8 after 10 min, while DeltaPO (2) = 4.3 +/- 3.2 mmHg; p < 0.05; n = 8 after 30 min), in parallel with a slow and progressive increase in systemic PaCO (2). The optic disc PO (2) increased much more significantly after injection of acetazolamide under systemic hyperoxia (DeltaPO (2) = 13.3 +/- 3.1 mmHg; p < 0.001; n = 8)., Conclusions: Systemic hyperoxia alone is not sufficient to increase substantially the optic disc PO (2) in miniature pigs due to a vasoconstrictor effect. Intravenous injection of acetazolamide can increase the optic disc PO (2) progressively, due to a vasodilatory effect of elevated systemic PaCO (2). The association of acetazolamide injection with systemic hyperoxia can further improve the oxygenation of the optic disc.

Background: Visual stimulation is increasingly used to investigate the coupling between neuronal activity, blood flow and metabolism in the neural tissue of the ocular fundus. In an attempt to clarify whether the oxygen metabolism is involved in this coupling, we investigated the changes in the partial pressure of oxygen of venous blood (pO (2,blood)) in the optic nerve head of pigs in response to two different visual stimuli., Materials and Methods: In 3 miniature pigs, the pO (2,blood) was measured in the optic disk rim using the technique of phosphorescence quenching by oxygen. This parameter was recorded every 8 seconds during a dark-to-light transition and during diffuse luminance flicker (field of 30 degrees centered at the optic disk, temporal frequencies of 2 to 80 Hz)., Results: The venous pO (2,blood) level (mean +/- standard deviation) did not change between dark- and light-adapted conditions (26.2 +/- 5.3 and 26.0 +/- 6.2 mm Hg, respectively), nor did we observe any transient change of pO (2,blood) during the light adaptation phase. On the other hand, the venous pO (2,blood) increased, on average, relative to its level during continuous light conditions (24.5 +/- 1.9 mm Hg) by at least 6 % for all flickering frequencies, with a maximum response of 14 % at 15 Hz., Conclusions: The phosphorescence quenching technique can reveal changes in venous pO (2,blood) induced by visual stimulation. Our results show that the pO (2,blood) in the optic nerve head of miniature pigs does not change with the light adaptation state of the retina, but increases during flicker stimulation with a band-pass type response. The previously reported increase of the ONH blood flow in response to flicker stimulation could lead to this increase of pO (2,blood).

Purpose: To evaluate the variations in preretinal PO2 in normal and in ischemic postexperimental branch vein occlusion (BRVO) retinal areas during normoxia, hyperoxia (100% O2) and carbogen (95% O2, 5% CO2) breathing., Methods: Preretinal PO2 measurements were obtained in intervascular retinal areas far from the retinal vessels of 13 anesthetized miniature pigs with oxygen-sensitive microelectrodes (10 microm tip diameter) introduced through the vitreous cavity by a micromanipulator. The microelectrode tip was placed at 50 microm from the vitreoretinal interface in the preretinal vitreous. PO2 was measured continuously for 10 minutes in systemic normoxia, hyperoxia (100% O2 breathing) and carbogen (95% O2, 5% CO2) breathing. A BRVO was induced with an argon green laser, and oxygen measurements were repeated in normoxia, hyperoxia and carbogen breathing., Results: In hyperoxia, preretinal PO2 remained almost constant in both normal retinas (DeltaPO2=1.33 mmHg +/- 3.39; n=13) and ischemic retinas (DeltaPO2=3.73 mmHg +/- 2.84; n=8), although systemic PaO2 significantly increased. Carbogen breathing induced a significant increase in systemic PaO2 and PaCO2. Furthermore, it significantly increased preretinal PO2: DeltaPO2=23.05 mmHg +/- 17.06 (n=12) in normal retinas, and DeltaPO2=22.54 mmHg +/- 5.96 (n=6) in ischemic retinal areas., Conclusions: Systemic hyperoxia does not increase preretinal PO2 significantly in normal and ischemic post-BRVO retinal areas of miniature pigs, as hyperoxia induces a decrease in the retinal blood flow. Carbogen breathing significantly increases preretinal PO2 in normal and in ischemic post-BRVO retinal areas. This effect is probably due to the vasodilatation of the retinal arterioles induced by the intravascular PaCO2 increase.

Exudative age-related macular degeneration (ARMD) is benefiting at present from new therapeutic approaches. Randomized clinical trials have demonstrated the efficacy of photodynamic therapy (PDT) in stabilizing visual acuity at 3 years. The basis of PDT consists in activating a photosensitizer with an adapted laser wavelength. Functional results are obtained on the basis of a strict classification of type of the new vessels responsible for exudative ARMD, based on fluorescein angiography. Thus, subfoveal lesions, in the form of either predominantly classic (visible new vessels>50%) or occult choroidal neovascularization (CNV), are the only indication for this therapy. Classic juxtafoveal CNV, where laser photocoagulation thermal burns may extend into the foveola, may be an extension of the indication of PDT. The follow-up after PDT is based on fluorescein angiography findings. The extension and persistence of leakage from the CNV remains an indication for retreatment. Ongoing studies are evaluating a number of features in order to define the responder group and possibly simplify the retreatment indications.

We present the case of a 54-year-old man with a previous history of central retinal vein occlusion in the right eye, who developed an idiopathic polypoidal choroidal vasculopathy in the right eye and an epiretinal membrane in the left eye. The patient's medical history disclosed arterial hypertension controlled with medical treatment. Although idiopathic polypoidal choroidal vasculopathy has been associated with several conditions, this is the first time that this entity has been described in the literature in association with central retinal vein occlusion.

Purpose: To compare the anatomic and functional results of primary vitrectomy alone or vitrectomy-scleral buckling for pseudophakic retinal detachment (RD). Vitrectomy permits a detailed view of the peripheral retina, so otherwise undetectable holes or additional small lesions can be found which, left untreated, may cause a residual RD., Patients and Methods: Twenty-four consecutive pseudophakic eyes with pseudophakic RD were operated by vitrectomy and encircling band (Group I) and 27 additional cases were operated on by vitrectomy alone (Group II). Internal subretinal fluid drainage, using liquid perfluoro-n-octane, endolaser, and/or cryocoagulation and fluid-air exchange with SF6 20%, was applied in all cases. Preoperative findings and intraoperative and postoperative complications as well as final results were analyzed., Results: Preoperatively undetected retinal holes were identified in 7 of the 51 eyes and additional retinal holes were found in 21. The mean follow-up was 14 months for Group I and 11.5 months for Group II. The retina was successfully reattached with a single operation in 22 of 24 eyes (92%) in Group I. One eye had a recurrence of RD due to an unsuccessfully treated preexisting retinal tear. Proliferative vitreoretinopathy (PVR) was observed in one case with recurrence of RD. In both cases, a second operation achieved retinal reattachment. In Group II, the retinas were attached with a single operation and visual acuity improved by an average of four or more lines in 62.5% of the vitrectomy-buckling group and in 55.5% of the vitrectomy group. The most frequent complication was a transient hypertony, in 21 cases., Conclusions: Surgical treatment of pseudophakic RD, combining vitrectomy and scleral buckling or vitrectomy alone, achieves very good anatomic and functional results. The advantages include more efficient detection of the peripheral detachment causing retinal lesions, and a lower redetachment rate than after extraocular surgery only.

Unlabelled: ZIEL: To investigate the relationship between velocity (Velch), blood volume (Volch) and blood flow (Fch), and the mean ocular perfusion pressure (PPm) in the foveal region, and to determine how the regulatory capacity of the choroidal circulation is affected after an encircling buckle procedure., Methods: We investigated both pseudophakic eyes of 6 patients (age range 56-79 years) in a masked study. Subjects presenting eye diseases (glaucoma, uveitis, diabetic retinopathy) as well as systemic diseases were excluded from the study. All subjects had in one eye a successful management of retinal detachment with an encircling buckling; the second eye was considered as control. Measurements of Velch, Volch and Fch were obtained by Laser Doppler Flowmetry (LDF) at baseline and during isometric exercise (squatting)., Results: In the operated eyes, Velch and Fch increased significantly (ANOVA, p < 0.05) during the PPm raise, which was not the case for Volch (ANOVA, p > 0.05). In the control eyes, all hemodynamic parameters remained unaffected by the PPm increase (ANOVA, p > 0.05). The response of Velch and Fch was significantly different (ANCOVA, p < 0.002) between operated and control eyes., Conclusion: These results suggest that encircling buckle does affect subfoveal choroidal blood flow regulation, which may explain a possible macular dysfunction in the operated eyes.

Background: Fungal endophthalmitis represents a significant cause of ocular morbidity, affecting in the majority of cases patients in poor general conditions. The eye is typically involved by hematogen dissemination, and the germ induces a chorioretinitis associated with an important panuveitis., Patients and Methods: Four patients were examined. They complained of a progressive reduction of vision, associated with photophobia. Ophthalmologic examination disclosed an important panuveitis. Investigations showed a fungal chorio-retinitis in all cases. Risk factors were intra-venous toxicomania, longterm parenteral nutrition and traumatism of the sinuses., Results: Vitreous cultures were positive for Candida albicans (3 patients) and for Aspergillus fumigatus (1 patient). Blood cultures were negative in the four cases. Three patients were treated with anti-fungal medication (fluconazole, itraconazole) associated with a vitrectomy by pars plana. One patient was treated by anti-fungal therapy only. Clinical evolution was satisfactory in all cases. Final vision was 10/10 in three cases and 5/10 in one. One patient developed a retinal detachment and an epiretinal membrane. Follow-up was 7 months (2-16 months)., Conclusion: The evolution of these four cases suggests that a rapid anti-fungal therapy associated with or without a vitrectomy represent a favourable therapeutic option when a fungal infection is suspected.