Claudio Azzolini

OCT images and surgery of juvenile Macular retinoschisis.

We describe three cases of X-linked juvenile retinoschisis confined to the posterior pole of the eye, one of which surgically treated. In the first two cases, in vivo optical coherence tomography (OCT) had revealed a cleavage plane in both nerve fiber and outer retinal layers. In the two similar operated eyes of the third case, postoperative OCT had revealed the disappearance of macular schisis in the eye with good recovery of visual function after surgery. On the contrary, it had revealed a persistent splitting of the retina in the other eye, not clinically visible, which explained the poor recovery of visual function after surgery. In cases with progressive worsening of macular involvement in X-linked juvenile retinoschisis, highly accurate surgery may be considered, and the pre- and postsurgical OCT monitor of these patients is indicated.

Peribulbar anesthesia with either 0.75% ropivacaine or a 2% lidocaine and 0.5% bupivacaine mixture for vitreoretinal surgery: A double-blinded study

UNLABELLED No study has evaluated the efficacy of ropivacaine in peribulbar block for ophthalmic surgery. The purpose of this prospective, randomized, double-blinded study was to compare ropivacaine and a lidocaine-bupivacaine mixture in peribulbar anesthesia. Sixty ASA physical status I or II patients scheduled for elective vitreoretinal surgery were randomized to receive a peribulbar block with 8 mL of either 0.75% ropivacaine (ropivacaine group, n = 30) or a 1:1 mixture of 2% plain lidocaine and 0.5% plain bupivacaine (lido-bupivacaine group, n = 30). Time required for onset of surgical anesthesia, quality of postoperative analgesia, incidence of side effects, and analgesic consumption were recorded. Surgical block was achieved after 8 +/- 5 min in the lido-bupivacaine group and after 10 +/- 5 min in the ropivacaine group (P = 0.23). A 3-mL supplemental injection 15 min after block placement was required in 6 patients in the lido-bupivacaine group (20%) and in 10 patients in the ropivacaine group (33%) due to inadequate motor block (P = 0.38). On Postoperative Day 1, 26 patients in the ropivacaine group (87%) reported no pain at the verbal rating score, compared with 18 patients in the lido-bupivacaine group (60%) (P = 0.005). We conclude that 0.75% ropivacaine may be a suitable choice when performing peribulbar anesthesia for vitreoretinal surgery. IMPLICATIONS Quick onset of block with prolonged postoperative analgesia is an important goal in regional anesthesia for ophthalmic surgery. Evaluating clinical properties of 0.75% ropivacaine and a 1:1 mixture of 2% lidocaine and 0.5% bupivacaine for peribulbar anesthesia, we demonstrated that ropivacaine has an onset similar to that of the lidocaine-bupivacaine mixture and provides a better quality of postoperative analgesia.

Updating on intraoperative light-induced retinal injury

We are presenting the state of knowledge concerning intraoperative light-induced retinal injury, considered to be a combination of photic retinopathy and retinal photocoagulation. It may arise from retinal light exposure to the operating microscope or to the fiberoptic endoilluminator. Ultraviolet and short-wavelength visible light are more dangerous than longer wavelength light. Many risk factors may facilitate the onset of this iatrogenic disease following surgery. Many aspects of the retinal damage are still poorly understood. Many mild light-induced retinal injuries probably remain undiagnosed in routine postoperative examination. Current appropriate light filters are not the definitive solution. Appropriate precautions should be taken during both anterior segment and vitreoretinal surgery.

Axial Length and Refraction in Retinal Vein Occlusions

To assess whether axial length and refraction are risk factors for retinal vein occlusion, we measured these parameters in 88 consecutive patients with unilateral branch retinal vein occlusion (BRVO), in 58 consecutive patients with unilateral central retinal vein occlusion (CRVO) and in 50 patients selected as a control group. Patients and controls were free or affected by systemic or local predisposing factors. We compared eyes with CRVO with control eyes, eyes with BRVO with control eyes, and eyes with CRVO with eyes with BRVO. Comparing CRVO eyes and controls, none of the investigated variables was shown to be significant. From the analysis of BRVO eyes versus controls, it resulted that refraction was the only variable which played the role of an independent prognostic factor. When comparing BRVO eyes with CRVO eyes, we found that age was slightly related to the development of BRVO. In conclusion, faulty refraction appeared to be a risk factor for the development of BRVO. We did not find any influence of axial length on the occlusion of retinal veins.

Double‐frequency Nd:YAG laser vs. argon‐green laser in the treatment of proliferative diabetic retinopathy: Randomized study with long‐term follow‐up

A randomized clinical trial using the argon‐green (514 nm) and the double‐frequency Nd:YAG (532 nm) lasers was carried out on 42 eyes with proliferative diabetic retinopathy (PDR), with the aim of assessing the long‐term effects of double‐frequency Nd:YAG panretinal photocoagulation (PRP).

Ultrasound biomicroscopy following the intraocular use of silicone oil.

We evaluated the ultrasound biomicroscopy findings and the amount and location of silicone oil residue in anterior structures of the eye before and after silicone oil removal. We examined the anterior structures in 40 silicone oil 1000 cs-filled eyes at the end of silicone oil tamponade time (mean silicone oil tamponade duration 5.1 months), and in the same eyes after silicone oil removal. High resolution ultrasound biomicroscopy, 50 MHz transducer, 50 νm of resolution, was used. Silicone oil droplets - often not ophthalmoscopically visible - appeared as highly reflective images with after ringing effect. They were present in the anterior structures of the eye in up to 95% of eyes with silicone oil in the vitreous cavity, and in up to 87.5% after careful silicone oil removal. With ultrasound biomicroscopy it was possible to identify small silicone oil droplets with a typical morphological appearance. Once silicone oil is used in vitreoretinal surgery, its complete removal from the anterior structures of the eye is very difficult to achieve later on.

Endophotocoagulation through perfluorodecalin in rabbit eyes.

Retinal laser endophotocoagulation through perfluorodecalin was studied in six eyes of three Dutch-belted rabbits after vitrectomy. Both the energy density threshold (EDT/50) and the energy threshold necessary to obtain a therapeutic lesion were evaluated. Both argon and semiconductor diode laser endophotocoagulators were used. The amount of laser power energy and the histology of chorioretinal lesions were similar when photocoagulating through perfluorodecalin, compared to photocoagulation through balanced salt citrate-buffered solution. This experimental study indicates that no extra care is necessary when retinal endophotocoagulation is performed through perfluorodecalin, as long as circular spots are obtained and energy is delivered symmetrically to the target site.

New semiconductor laser for vitreoretinal surgery

We Investigated the potential application in vitreoretinal surgery of a CW diode laser with cutting capabilities.

Influence of Scone Oil on Iris Microangiopathy in Diabetic Vitrectomized Eyes

PURPOSE This study evaluates the influence of intraocular silicone oil on iris diabetic microangiopathy in diabetic vitrectomized eyes. METHODS The authors examined 20 eyes of 20 patients with diabetes undergoing primary vitrectomy for fractional diabetic retinal detachment, endophotocoagulation, and 1000 centistokes silicone oil tamponade. The vascular status of the iris in these eyes was examined by iris fluorescein angiography once before silicone oil injection and again when it was removed (mean follow-up, 8.3 months). RESULTS Iris diabetic microangiopathy, including breakdown of the blood-iris barrier and iris neovascularization, improved or remained stable in 40% of eyes. It worsened in 60% of eyes, including all aphakic eyes. Neovascular glaucoma developed in one of them. A significant correlation was found between worsening of iris diabetic microangiopathy and both aphakia (P = 0.01) and severe immediate postvitrectomy inflammation (P = 0.02). Eyes with recurrent retinal detachment (n = 4) showed worsening of iris diabetic microangiopathy, but this was not significantly correlated. CONCLUSION Aphakic vitrectomized eyes have a higher risk of iris diabetic microangiopathy developing, even after silicone oil tamponade. Immediate postoperative intraocular inflammation also is a risk factor for worsening of iris diabetic microangiopathy in phakic eyes. Recurrence of retinal detachment was not significantly correlated with worsening of iris status.

Age-related macular degeneration and vitreous hemorrhage

Age-related macular degeneration led to vitreous hemorrhage (VH) in six eyes of four patients. Macular involvement was bilateral in three patients and fluorescein angiography performed before VH showed extensive subretinal hemorrhage in the macular region in all eyes. We examine the possible causal mechanisms of VH resulting from age-related macular degeneration. Local risk factors, as outlined in our series by fluorescein angiography, are discussed and systemic risk factors are considered. Three out of the six eyes underwent pars plana vitrectomy for removal of intravitreal blood, and had severe inflammatory reactions in the postoperative period. In the three non-operated eyes spontaneous reabsorption of VH was observed at the end of follow-up.