Macular pucker: to peel or not to peel the internal limiting membrane? A microperimetric response.

BACKGROUND: To compare functional and anatomical outcomes after idiopathic macular pucker removal between eyes that underwent internal limiting membrane (ILM) peeling and eyes that did not. METHODS: In this multicentric, randomized clinical trial, 60 eyes of 60 patients affected with idiopathic macular pucker were enrolled. Thirty eyes underwent 23-gauge pars plana vitrectomy associated with ILM peeling ("ILM peeling group"), whereas 30 eyes did not undergo ILM peeling ("ILM not peeling group"). Retinal sensitivity, frequency of microscotomas, and all the other microperimetric parameters were tested by MP1 microperimetry. Best-corrected visual acuity was investigated with the Early Treatment Diabetic Retinopathy Study chart. Anatomical outcomes were analyzed with spectral domain optical coherence tomography. RESULTS: After a 12-month follow-up, the mean retinal sensitivity in the 4° central area showed a greater and faster recovery in the ILM not peeling group than in the ILM peeling group (P = 0.041). The number of absolute microscotomas (0 dB) within the 12° central retinal area was significantly higher in the ILM peeling group than in the ILM not peeling group (P = 0.044). CONCLUSION: The ILM not peeling group seems to show better outcomes than the ILM peeling group as measured by mean retinal sensitivity and number of microscotomas after a 12-month follow-up.

Intravitreal ranibizumab for predominantly hemorrhagic choroidal neovascularization in age-related macular degeneration.

PURPOSE: To evaluate the effects of intravitreal ranibizumab monotherapy on predominantly hemorrhagic choroidal neovascularization with foveal involvement associated with age-related macular degeneration. MATERIALS AND METHODS: Twenty-two consecutive eyes with hemorrhagic neovascularization were treated with 3 monthly intravitreal ranibizumab injections. Additional injections were administered according to retreatment criteria during 12 months of follow-up. RESULTS: A mean of 6.64 ± 1.36 injections was administered. Overall, the mean visual acuity increased from 10.90 ± 6.02 to 12.81 ± 8.34 ETDRS letters (p > 0.05) at 12 months. The 'early treatment group' gained a mean of 2.83 ± 2.24 ETDRS letters (p < 0.05), while the 'late treatment group' gained a mean of 0.30 ± 1.25 ETDRS letters (p > 0.05) with significant differences between the groups (p < 0.05). A progressive resolution of macular bleeding was registered in 20 patients (mean time: 5.3 ± 1.6 months). CONCLUSIONS: Ranibizumab injections can be considered a beneficial approach for the management of predominantly hemorrhagic choroidal neovascularization with foveal involvement associated with age-related macular degeneration. Furthermore, the time interval between hemorrhage and the first injection seems to be an important predicting factor of final visual acuity.

Theoretical model and design of a device to reduce the influence of environmental factors on refractive surgery outcomes.

Recently many different groups show that environmental temperature and relative humidity affects the outcomes of refractive surgery performed by excimer lasers in an unpredictable fashion. A theoretical model of the water vapor absorption at 193 nm wavelength is presented and discussed in order to quantitatively assess the influence of environmental parameters on the laser energy that actually reaches the corneal surface. Model simulations show that laser energy absorption (up to 7% of the available energy) occurs along the path of laser beam, into the existent space between the laser beam source and the patient's eye, and is caused by environmental temperature and relative humidity (respectively 35 degrees C and 95%). Our findings suggest that this energy loss reduces the ablation rate, producing a significant under-correction of the treated corneas. A cost effective device which keeps thermo hygrometric parameters constant along the laser beam path, is also provided.