Francesco Bandello

Macular Thickness Measured by Optical Coherence Tomography (OCT) in Diabetic Patients

Purpose 1) To compare macular thickness (MT) by optical coherence tomography (OCT) in diabetics and controls; 2) to assess the relationship between MT and stage of diabetic retinopathy (DR) and macular edema (ME); 3) to quantify MT changes after laser treatment for ME. Methods One-hundred and thirty-seven patients with diabetes mellitus (216 eyes) were admitted to the study and examined by stereo-color fundus photos, retinal fluorangiography and OCT. DR was classified as: 1) no DR (46 eyes: 21.3%); 2) background DR (66 eyes: 30.6%); 3) pre-proliferative DR (50 eyes: 23.1%); 4) proliferative DR (54 eyes: 25%). The study group was then divided into three ME groups: 1) no edema (65 eyes: 30.1%); 2) not clinically significant ME (no CSME) (45 eyes: 20.8%); 3) clinically significant macular edema (CSME) (106 eyes: 49.1%). Three-month follow-up tomograms were taken to evaluate eyes laser-treated only for ME. The control group consisted of 50 eyes of 50 non-diabetic, age- and sex-matched subjects. Results MT was 369.3±163.2 μm in diabetics and 161.9±12.9 μm in controls (p<0.001). In the four DR groups it was: 1) 211.0±37.6 μm; 2) 370.8±159.6 μm; 3) 419.1±138.2 μm; 4) 456.1±162.0 μm (p<0.001). In the three ME groups, MT was: 1) 227.8±53.4 μm; 2) 321.8±124.2 μm; 3) 476.2±146.6 μm (p<0.001). In the 52 eyes treated with laser photocoagulation of the posterior pole only and with a follow-up > 3 months, MT before and after treatment was 468.2±83. 17 μm and 372.1±120.63 μm. Conclusions MT was greater in diabetics than controls and tended to increase with DR and ME severity. OCT is a sensitive technique for detecting early diabetic macular abnormalities and quantifying their reduction after laser treatment.

Nonvisible subthreshold micropulse diode laser (810 nm) treatment of central serous chorioretinopathy: A pilot study

Purpose To verify the efficacy of nonvisible micropulse diode laser irradiation in the treatment of central serous chorioretinopathy (CSC). Methods Twenty-two patients with CSC for a total of 24 eyes with a disease duration longer than 3 months were included in a prospective study. Patients underwent Early Treatment Diabetic Retinopathy Study visual acuity (VA) examination, dilated ophthalmoscopy fluorescein angiography and optical coherence tomography before treatment and during follow-up. Treatment with a micropulse diode laser was given with a duty cycle of 15%. Multiple spots were placed over and adjacent to the area of retinal pigment epithelium leak or decompensation. Results Mean follow-up was 14 months (range 3–36 months). Powers used ranged from 1 to 2 W (mean 1.35 W). Mean number of spots was 215 (range 90–400). Fourteen eyes were treated once, nine eyes received two to three treatments, and one eye had five treatments during a follow-up of 3 years. Subretinal fluid was resolved or improved in two third of cases 1 month after laser treatment, and in three-quarters at the end of follow-up. Mean retinal thickness was 328 μm, 197 μm, and 168 μm before, 1 month after irradiation, and at the end of follow-up, respectively. No evidence of RPE or retinal changes due to laser treatment were discernible in most of the eyes. Median VA was 20/32 (range 20/100–20/20) before treatment and 20/25 (range 20/200–20/20) at the end of the follow-up. Conclusions Nonvisible micropulse diode laser may have efficacy in the treatment of CSC. A randomized study with larger series is needed.

Spontaneous resolution of a shallow detachment of the macula in a highly myopic eye

PURPOSEnTo report a case of pathologic myopia with shallow detachment of the macula and anatomic reattachment after spontaneous posterior vitreous separation.nnnDESIGNnObservational case report.nnnMETHODSnA 66-year-old woman with pathologic myopia presented with decreased vision of 20/400 in her left eye. Biomicroscopy showed myopic chorioretinal changes, posterior staphyloma, and a shallow macular elevation. Optical coherence tomography was performed at the initial and follow-up examinations.nnnRESULTSnInitial optical coherence tomography revealed a retinal detachment, retinoschisis, and incomplete posterior vitreous detachment. One and one-half years after the initial visit the patients best-corrected visual acuity improved to 20/200, and optical coherence tomography disclosed macular reattachment, release of vitreous adhesions, and restoration of normal retinal tomographic appearance.nnnCONCLUSIONSnSpontaneous resolution of chronic shallow detachment of the macula in highly myopic eyes may occur and can be attributed to spontaneous posterior vitreous detachment.

Early vascular changes induced by transpupillary thermotherapy of choroidal neovascularization

OBJECTIVEnTo study early direct effects of transpupillary thermotherapy (TTT) on choroidal neovascularization (CNV) and choroid.nnnDESIGNnRetrospective, noncomparative interventional case series.nnnPARTICIPANTSnSixty-four eyes with subfoveal CNV.nnnINTERVENTIONnTTT was delivered using a diode laser at 810 nm through a contact lens. Exposure time was 60 seconds with a power/diameter ratio of 247 mW/mm. The end point was an invisible treatment with no color change at the retina level.nnnMAIN OUTCOME MEASURESnFluorescein and indocyanine green angiographic findings within 1 hour, and at 1, 2, and 4 weeks after TTT.nnnRESULTSnFluorescein angiography (FA) and indocyanine green angiography (ICGA) performed within 1 hour after TTT showed increased leakage of CNV and choroidal vessels. Follow-up at 1 and 2 weeks demonstrated a hypofluorescent area corresponding to the laser spot and absence of angiographic leakage seen on FA and ICGA. At 4 weeks after TTT, FA showed mottled hypofluorescence-hyperfluorescence of the TTT-treated area and absence of angiographic leakage.nnnCONCLUSIONSnTTT induces a characteristic dynamic sequence of vascular changes. Treatment with TTT can lead to absence of angiographic (FA and ICGA) leakage for 4 weeks. Determination of the long-term efficacy and visual implications awaits the results of clinical trials.

Diabetic macular edema: classification, medical and laser therapy

Purpose. to propose and describe a new classification of diabetic macular edema (DME) based on its etiopathogenetic features and to present efficacy and safety data on medical and laser treatments currently used and under investigation. Methods. available literature on DME has been reviewed and information provided by contact lens biomicroscopy, fluorescein angiography and optical coherence tomomography has been combined; published data from trials and reports investigating effectiveness of medical and laser treatments were also analyzed. Results. DME was classified according to its main etiopathogenetic components: prevalently retinovascular, tractional and with taut attached posterior hyaloid, each of them having peculiar aspects on fundus, angiographic and tomographic examination. Focal laser treatment remains the only effective intervention, as shown by a large randomized controlled trial, but new less-invasive photocoagulation strategies (i.e., light laser photocoagulation and subthreshold micropulse diode laser) as well as pharmacological approaches (i.e., antioxidants, PKC inhibitors, aldose-reductase and AGE inhibitors, VEGF inhibitors, intravitreal triamcinolone) are emerging. Conclusions. based on our review a classification of DME was developed that may prove useful in making the appropriate treatment decision; the new laser and pharmacological treatments currently investigated are promising and need to be confirmed by large, controlled clinical trials.

Idiopathic macular hole surgery with low-concentration infracyanine green-assisted peeling of the internal limiting membrane.

PURPOSEnTo evaluate the efficacy of pars plana vitrectomy with infracyanine green (IFCG)-assisted internal limiting membrane peeling for the treatment of idiopathic macular hole.nnnDESIGNnProspective, noncomparative interventional case series.nnnMETHODSnThirty-eight consecutive eyes of 35 patients with idiopathic macular hole were included in the study. Patients underwent early treatment diabetic retinopathy (ETDRS) visual acuity examination, dilated ophthalmoscopy, and optical coherence tomography before treatment and during follow-up. Fluorescein angiography was done in selected cases. Patients underwent a three-port pars plana vitrectomy with complete posterior hyaloid and epiretinal membrane removal. The internal limiting membrane (ILM) was stained with 0.5 cc of IFCG (0.5 mg/ml, 308 mOsm) and peeled up to the vascular arcades. Perfluoropropane gas (C(3)F(8)) 10% was used as tamponade.nnnRESULTSnMean follow-up duration was 10 +/- 5 months (range, 3 to 24 months). Six eyes had stage 2 macular hole, 15 eyes stage 3, and 16 eyes stage 4. Overall, 37 of 38 macular holes closed after a single surgery. Median visual acuity was 20/100 (range, 20/400 to 20/50) before surgery and 20/50 (range, 20/640 to 20/25) after surgery. Visual acuity after surgery was 20/50 or better in 24 of 38 (63.1%) eyes. Twenty-five (65.8%) eyes improved by 2 or more lines, nine (23.7%) eyes were stable, and four (10.5%) eyes worsened by 2 or more lines.nnnCONCLUSIONSnThis study suggests that IFCG (0.05%) effectively stains the ILM with apparent safety, and that IFCG-assisted peeling of the ILM may be useful in the treatment of idiopathic macular hole.

Selective photocoagulation in Coats' disease: ten-year follow-up.

PURPOSEnThe diagnostic hallmark of Coats disease is development of light bulb telangiectasis in the retinal periphery, leading to posterior pole intraretinal and subretinal exudation. Even after complete obliteration of all abnormal vessels and resorption of all exudates, follow-up examinations are mandatory for several years.nnnMETHODSnWe retrospectively analyzed the charts, pictures and/or fluorescein angiographies of a series of 32 consecutive patients, in which the diagnosis of Coats disease was made. All patients underwent selective photocoagulation of the telangiectasis using a yellow-dye laser. Efficacy of treatment was monitored with drawings and/or fluorescein angiographies.nnnRESULTSnAll our patients had unilateral disease, with macular involvement and exudative retinal detachment. Visual acuity improved in one patient, decreased from light perception to blindness in another, and was unchanged in the remainder.nnnCONCLUSIONSnThis is the first report of anatomical benefits from treatment with a yellow-dye laser (i.e., selective photocoagulation without cryotherapy or drainage) despite the presence of a severe form of Coats disease. Our young Coats patients responded quickly to treatment. With successful obliteration of the abnormal vasculature, exudates began to absorb in about 4 to 8 weeks although, in some cases, 10 to 12 months were needed to obtain resolution of the exudative detachment. Poor visual outcome of 20/100 or worse was common. In Coats patients, the key issue is continuous control and long-term follow-up. (Eur J Ophthalmol 2002; 12: 501-5).

When and how to do a grid laser for diabetic macular edema

Macular edema is a common feature of posterior segment diseases. It is an expression of abnormal permeability in either retinal vessels (inner blood-retinal barrier) or in the retinal pigment epithelium (outer blood-retinal barrier). It occurs in either a diffuse pattern where the macula appears generally thickened or, in more severe cases, as cystoid edema with the typical petaloid appearance. Grid laser treatment may be useful to reduce macular edema. Spots of 100–250 micrometers in diameter are applied to the whole posterior pole, one to two groups apart. The foveal avascular zone remains untouched. In patients treated bilaterally, areas temporal and nasal to the macula must be spared to prevent the development of deep scotomas. The mechanism yielding positive results with the grid technique is still debated. Among the most reliable hypotheses are: Proliferation of pigment epithelial cells, followed by and improved efficiency of the outer blood-retinal barrier; proliferation of endothelial cells in retinal capillaries followed by an improved efficiency of the inner blood-retinal barrier; improvement of the retinochoroidal exchanges, and finally, release by coagulative necrosis of a factor able to improve the efficiency of the blood-retinal barriers. Lasers with long wavelengths, such as krypton red and diode, are the most appropriate ones to perform grid treatment.

Theoretical bases of non-ophthalmoscopically visible endpoint photocoagulation

Laser photocoagulation is a photothermal process in which heat is produced by the absorption of laser energy by targeted tissues. The purpose of the treatment is to induce thermal therapeutic damage, which causes biological reactions and ultimately beneficial effects. The current endpoint of laser photocoagulation of the chorioretina is an ophthalmoscopically visible retinal whitening. Retinal blanching is the sign that the retina itself has been thermally damaged and results in a number of undesired adverse events. The mechanisms underpinning the efficacy of laser photocoagulation are still poorly understood. However, recent hypotheses postulate that full thickness retinal damage may not be needed to obtain beneficial therapeutic effectiveness. Preliminary studies with laser photocoagulation on animals demonstrated the ability to create therapeutic lesions confined around the Retinal Pigment Epithelium (RPE) cells without causing apparent damage to the overlying retina. The laser impacts were not visible by slit lamp biomicroscopy at the time of laser delivery. Recent experiments showed that the beneficial effect of retinal photocoagulation is mediated by factors derived from the RPE. Non Ophthalmoscopically Visible Endpoint Photocoagulation (NOVEP) protocols might allow treatments that confine minimal therapeutic damage around the cells of the RPE and minimize the damage to the neurosensory retina.

Bilateral juxtafoveolar telangiectasis in monozygotic twins

PURPOSEnTo report the clinical and angiographic features of two monozygotic twins affected by bilateral group 2 idiopathic juxtafoveolar telangiectasis.nnnMETHODnCase reports.nnnRESULTSnTwo 64-year-old women, who were identical twins, were suffering from visual loss. One twin had suffered from visual loss for 1 year and had a visual acuity of 20/25 in both eyes, and the other twin had suffered for 2 years and had a visual acuity of 20/30 in both eyes. Fluorescein angiography disclosed similar fundus features. An analogous area of capillary telangiectasis and leakage was observed in the right macula, where no intraretinal pigment was seen; the left macula showed a similar amount of intraretinal pigment associated with tiny right-angle venules and minimal leakage.nnnCONCLUSIONnThis observation raises the issue of genetic influences in the pathogenesis of this disease.