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M Codenotti

Publications and source records attributed to M Codenotti.

7 recordsLinked to original sources

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.

Amides↗

New semiconductor laser for vitreoretinal surgery.

BACKGROUND AND OBJECTIVE: We investigated the potential application in vitreoretinal surgery of a CW diode laser with cutting capabilities. STUDY DESIGN/MATERIALS AND METHODS: A semiconductor CW laser emitting 300 mW optical power at 1.94 microns wavelength was used to perform retinotomies and membrane cutting on rabbit eyes. The device was integrated into a dedicated controller. The laser radiation was delivered through a low attenuation fused silica optical fiber of 200 microns core size, terminating into a 20-gauge endo-ocular handpiece. Histological aspects of threshold lesions obtained on the rabbits' chorioretina were evaluated by light microscopy. RESULTS: We obtained circular and linear full-thickness retinotomies with contact and noncontact procedures using energy of 120 mJ (240 mW x 0.5 s). Using a non-contact procedure, a larger peripheral coagulation halo around the retinotomies was observed, as compared to the contact method. The adjacent zone of thermal damage ranged from 50 to 200 microns. Lower efficacy was obtained on experimentally induced epiretinal membranes, where only superficial ablation was achieved. CONCLUSION: The CW 2 microns diode laser will have a promising future in vitreoretinal surgery when a higher output irradiance is available.

Animals↗

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.

Animals↗

Influence of silicone 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.

Adult↗

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 microns 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.

Adolescent↗

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.

Adolescent↗

Optical coherence tomography in idiopathic epiretinal macular membrane surgery.

PURPOSE: To evaluate the usefulness of Optical Coherence Tomography (OCT) images for surgical indication, intraoperative management and postoperative outcome of patients with idiopathic epiretinal macular membrane (IEMM). METHODS: 28 selected eyes underwent surgery for removal of IEMM. The patients' mean age was 57.3 years. The macular region and the IEMMs were studied before and after surgery using OCT, slit-lamp biomicroscopy and fundus photography. The mean postoperative follow-up was 6.2 months (range 1.3-14). RESULTS: Preoperatively, in 12 of the 28 eyes (42.9%) only the OCT images revealed IEMM partially separated from the macula, with tractional focal point(s) of attachment to the macular region. In the other 16 eyes (57.1%) in which IEMMs were totally adherent to the macular region, the membranes were barely visible by OCT in 13 eyes and not visible in three. Intraoperatively, the surgeon was guided in the peeling procedures. A significant correlation (p < 0.001) was found between visual acuity and macular thickness before surgery and at the end of the postoperative follow-up. CONCLUSIONS: OCT images provide very useful information for the surgical indication, intraoperative management and postoperative outcome of patients with IEMM.

Adolescent↗