Peribulbar anesthesia in 750 patients treated with oral anticoagulants.

AIM: To check the safety of continuation of oral anticoagulants in ophthalmic procedures requiring a peribulbar anesthesia. METHOD: A prospective case control study included 750 patients with oral anticoagulants in group A and 750 patients who had never been treated with oral anticoagulant in group B. Hemorrhages were graded as follows: 1) spot ecchymosis of eyelid and or subconjunctival hemorrhage; 2) eyelid ecchymosis involving half of the lid surface area; 3) eyelid ecchymosis all around the eye, no increase in intraocular pressure; 4) retrobulbar hemorrhage with increased intraocular pressure. RESULTS: In group A, grade 1 was observed in 13 patients (1.74%) and grade 2 in 2 patients (0.26%). In group B, grade 1 was observed in 12 patients (1.6%) and grade 2 was absent. No 3 or 4 hemorrhage grade was encountered in both groups. There was not significant difference in grade 1 hemorrhage between both groups (P=0.21). CONCLUSION: Oral anticoagulants were not associated with a significant increase in potentially sight-threatening local anesthetic complications.

A semi-automated computer tool for the analysis of retinal vessel diameter dynamics.

Retinal vessels are directly accessible to clinical observation. This has numerous potential interests for medical investigations. Using the Retinal Vessel Analyzer, a dedicated eye fundus camera enabling dynamic, video-rate recording of micrometric changes of the diameter of retinal vessels, we developed a semi-automated computer tool that extracts the heart beat rate and pulse amplitude values from the records. The extracted data enabled us to show that there is a decreasing relationship between heart beat rate and pulse amplitude of arteries and veins. Such an approach will facilitate the modeling of hemodynamic interactions in small vessels.

Peribulbar block in patients scheduled for eye procedures and treated with clopidogrel.

Our hypothesis was that the continuation of clopidogrel does not increase the risk of eye hemorrhage, compared to patients not treated with clopidogrel, when a peribulbar anesthesia is required. Our prospective case-control study enrolled two groups of 1,000 patients scheduled for intraocular eye surgery requiring a peribulbar block. Patients treated with clopidogrel were included in group A (1,000 patients). Patients who had never been treated with clopidogrel constituted the control group (group B, 1,000 patients). Hemorrhages were graded as follows: 1 = spot ecchymosis of eyelid and or subconjunctival hemorrhage; 2 = eyelid ecchymosis involving half the lid surface area; 3 = eyelid ecchymosis all around the eye, no increase in intraocular pressure; 4 = retrobulbar hemorrhage with increased intraocular pressure. Grade 1 hemorrhages were observed in 30 patients (3.0 %) in group A and in 20 patients (2.0 %) in group B. No grade 2, 3, or 4 hemorrhage was encountered. There was no significant difference in the grading of hemorrhage between the groups (p = 0.017). Clopidogrel was not associated with a significant increase in potentially sight-threatening local anesthetic complications.

Peribulbar block in 500 patients scheduled for eye procedures and treated with acetyl salicylic acid.

OBJECTIVES: No guidelines are available in France for peribulbar block for eye procedures. It is our hypothesis that continued use of acetyl salicylic acid for forestalling myocardial or cerebrovascular ischemic events does not increase the risk of hemorrhage, compared with discontinuation of its use in patients who undergo eye procedures under peribulbar block. METHODS: For this prospective control study we enrolled two groups of 500 patients scheduled for intra-ocular eye surgery requiring a peribulbar block. Patients treated with acetyl salicylic acid were included in group A (500 patients). Patients who had never been treated with acetyl salicylic acid constituted the control group (group B: 500 patients). Hemorrhages were graded as follows: 1=spot ecchymosis; 2=lid ecchymosis involving half of the lid surface area or less; 3=lid ecchymosis all around the eye, without increase in intra-ocular pressure; 4=retrobulbar hemorrhage with increased intraocular pressure. RESULTS: In group A, lid hemorrhages (grade 1) were observed in 30 patients (6.0%). No grade 2, 3 or 4 hemorrhages were encountered in this group. In group B, lid hemorrhage (grade 1) was observed in 20 patients (4.0%) and grade 2 in one patient (0.2 %), but no grade 3 or 4 hemorrhages were encountered. Statistical tests showed the absence of significance between both groups. CONCLUSION: We conclude that between the groups with and without pre-operative acetyl salicylic acid the occurrence rate of lid hemorrhage was not significant in peribulbar block.

[Hypertensive retinopathy]. / Rétinopathie hypertensive.

Acute hypertensive retinopathy should be distinguished from retinal arteriolosclerosis. The presence of microvascular abnormalities in the ocular fundus increases the risk of heart and/or brain attack. At the clinical level, the current classification of chronic hypertensive retinopathy is based on the long-term risk of stroke. In research, a great number of studies are focused on the predictive value of retinal vascular diameters related to the general micro- and macrovascular disease.

Hypopyon uveitis (without scleritis) a manifestation symptom of relapsing polychondritis.

We report an atypical ocular symptom, hypopyon uveitis without scleritis encountered in relapsing polychondritis. Relapsing polychondritis should be considered in the differential diagnosis of sterile hypopyon uveitis.

Antibiotics concentrations in a patient with postoperative endophthalmitis.

We report a case of endophthalmitis who underwent a vitreous biopsy to assess sensitivity and to inject broad-spectrum intraocular antibiotics. Minimal inhibitory concentration (MIC) values of antibiotics against a coagulase-negative staphylococcus and Proprionibacterium acnes were also assessed.

Macular edema after corneal graft: a prospective study by optical coherence tomography.

PURPOSE: Vision recovery after corneal graft is sometimes limited by the occurrence of macular edema. The aim of this prospective study of 62 keratoplasty patients was to assess the incidence of macular edema by using optical coherence tomography (OCT 3; Stratus, Carl Zeiss Meditec, Dublin, CA) and to identify factors associated with edema. METHODS: Sixty-two patients who were all operated on by the same surgeon were examined by OCT 3, 1 and 3 months after corneal graft. RESULTS: The incidence of macular edema after keratoplasty was 9.6%. The surgical technique (penetrating vs lamellar keratoplasty) had no influence on the occurrence of edema (P > 0.05), but combined surgery significantly increased the risk of developing an edema (P < 0.05). CONCLUSION: Macular edema after keratoplasty seemed to be less frequent than expected (9.6%) and associated mainly with combined surgery.

Microvascular remodeling after occlusion-recanalization of a branch retinal vein in rats.

PURPOSE: To describe the time course of microvascular changes after transient branch retinal vein occlusion (BRVO) in rats. METHODS: BRVO was induced in pigmented rats by focal laser photocoagulation. The subsequent changes in the retinal angiogram were followed up, both in vivo by confocal scanning laser ophthalmoscopy and ex vivo by confocal microscopy. RESULTS: At day 1, capillary closure affected the three microvessel layer differentially, the intermediary layer being the most affected. Collateral veins, which were initiated by the dilation of deep-layer venules, pursued their course below adjacent arteries. These microvascular changes peaked between days 1 and 3. After recanalization at day 3, microvascular changes regressed gradually but incompletely, and at day 30 capillary closure and venule dilation persisted. CONCLUSIONS: Transient occlusion of a retinal vein in rats leads to short- and long-term microvascular remodeling upstream of the occlusion site. This study describes a model for the tridimensional arrangement of retinal microvessel that accounts for the topography of the early capillary closure and collateral vessel formation that occur after BRVO. In the long term, these changes regressed incompletely, with recanalization of the occluded vein, suggesting that after a short period of occlusion, microvascular changes may become at least partially independent of flow. Despite the intrinsically limited applicability of this model to human vein occlusion, the results suggest that even if therapeutic decompression of an occluded vein is performed early, it may not reverse capillary dropout completely.

Structural and hemodynamic analysis of the mouse retinal microcirculation.

PURPOSE: In the holangiotic retina, little is known about the connections between and the circulation within microvessel layers. The goal of the present study was to explore the three-dimensional arrangement and hemodynamics of mouse retinal microvessels. METHODS: Confocal microscopy was performed on fluorescein dextran-filled retinal flatmounts. Capillary velocity in the deep layer was measured by epifluorescence intravital microscopy. The changes in the studied parameters after branch retinal vein occlusion were evaluated. RESULTS: The superficial and intermediate layers are both asymmetric crossroads for capillary blood flow, with approximately 70% of the capillary connections directing the flow from the arterioles into the deep layer. The venous flow from the deep layer joins the major veins in the superficial layer through transverse venules, indicating that major veins are directly connected to the deep layer. Red and white blood cell velocities +/- SD in the deep layer were 1.26 +/- 0.34 and 0.8 +/- 0.32 mm/sec respectively. After branch vein occlusion, venule dilation and decreased velocity were observed in the deep layer. CONCLUSIONS: In the mouse retina, a tridimensional model of retinal microcirculation was established, showing that most microvessel connections on the arteriolar side direct the flow from the superficial to the deep layer, and vice versa on the venular side. However, the presence of direct arteriovenous connections in the superficial layer and the longer vessel length in the deep layer offer the possibility of actively modulating intraretinal flow. Compared with other capillary beds, both the capillary velocity and microhematocrit are high, a situation that favors nutrient delivery to the inner retina.

Silicone oil migration in the eyelid after vitrectomy for retinal detachment.

PURPOSE: To report a case of silicone oil intrusion in the upper eyelid, expressed by ptosis occurrence 19 years after surgery. METHODS: Vitrectomy followed by transscleral subretinal fluid drainage and silicone oil tamponade was performed on a 57-year-old man for retinal detachment. Nineteen years later, the patient was referred for mobile subcutaneous lumps of the upper right eyelid. Preoperative examination showed total invasion of the eyelid by silicone oil, as confirmed by pathology. RESULTS: Silicone oil leak developed through the transscleral drainage lumen and worsened with ocular hypertension. We assume that ptosis was induced by the weight of inflammatory tissue and consequently the development of a lymphoedema. CONCLUSION: We report a case of silicone ptosis. Two concomitant factors induced oil leakage: the puncture site and postoperative hypertonia.

Axon-tracing properties of indocyanine green.

OBJECTIVE: It has been shown recently that the application of indocyanine green (ICG) over the retinal surface is followed by prolonged staining of the optic disc. This study was performed to analyze the diffusion of ICG in the optic tract. METHODS: Anterograde diffusion of ICG was evaluated after injection into the vitreous of rabbits. Retrograde diffusion was evaluated after microinjection into the lateral geniculate nucleus of rats. RESULTS: Anterograde and retrograde diffusion occurred along the axons at a rate of about 2 mm per hour when ICG was injected. Anterograde staining of the visual pathway persisted for several weeks. After injection into the lateral geniculate nucleus, fluorescent retinal ganglion cells could be visualized for at least 7 days in conscious rats by conventional infrared photography. Microscopic examination findings of retrograde-labeled retinas showed the presence of ICG vesicles inside the axons, cytoplasm, and dendrites of retinal ganglion cells. No evidence of toxic effects was detected by optical microscopy. CONCLUSIONS: Indocyanine green is a fast bidirectional axonal tracer. Injection into normal vitreous results in long-term staining of the visual pathway. In vivo counting of ICG-labeled retinal ganglion cells in rats can be performed for several days after injection. Indocyanine green is therefore potentially of interest for use in experimental neurophysiological studies. CLINICAL RELEVANCE: The present results suggest that in humans, epiretinal application of ICG results in prolonged staining of the visual pathway. Therefore, additional studies of long-term toxic effects of ICG on neural cells are warranted before recommending its use in humans as an intraoperative tool for vitreoretinal surgery.