Photon-based high-dose single-fraction radiosurgery, an effective treatment modality for recurrent uveal melanoma.

Introduction: To evaluate and report the outcome of a patient with locally recurrent uveal melanoma (UM) previously treated with brachytherapy (BT), using a second personalized globe-sparing radiotherapy approach. Material and methods: In June 2020, a 78-year-old man arrived at our institution with diplopia and suspected uveal melanoma. At the ophthalmological evaluation (B-scan and A-scan ultrasonography) a lesion in the right eye at 6-7 hours of about 5 mm thickness, with internal lacunar areas, approximately 7 mm away from the limbus, was observed. The patient underwent ruthenium plaque BT at a total dose of 110 Gy prescribed to the apex of the tumour. At the follow-up, the lesion was under control until September 2021, but it recurred with a satellite exudative detachment in the lower and temporal sectors 7-10 hours. At the B-scan the lesion had a maximum thickness of 4.6 mm. Subsequently, in a multidisciplinary discussion, one single fraction stereotactic radiosurgery was scheduled. The prescribed dose was 27 Gy in the de-novo lesion and 24 Gy in the previously irradiated site. Stereotactic radiosurgery was performed in October 2021. Results: The time interval between the 2 treatments was 15 months. Twenty months after recurrence, local tumour control was observed, and no metastases were detected on follow-up examinations. No severe acute or late toxicity was observed due to the retreatment. Conclusions: Photon stereotactic radiotherapy is a feasible, acceptably tolerated modality, and it represents an eye-preserving treatment also for patients with recurrent UM unfit for BT.

An empirical approach to the definition of the target margins in eye radiosurgery.

INTRODUCTION: A system for stabilizing and monitoring eye movements during LINAC-based photon beam one single fraction stereotactic radiotherapy was developed at our Institution. This study aimed to describe the feasibility and the efficacy of our noninvasive optical localization system that was developed, tested, and applied in 20 patients treated for uveal melanoma. METHODS: Our system consisted of a customized thermoplastic mask to immobilize the head, a gaze fixation LED, and a digital micro-camera. The localization procedure, which required the active collaboration of the patient, served to monitor the eye movements during all phases of the treatment, starting from the planning computed tomography up to the administration of radiotherapy, and allowed the operators to suspend the procedure and to interact with the patient in case of large movements of the pupil. RESULTS: Twenty patients were treated with stereotactic radiosurgery (27 Gy in one fraction) for primary uveal melanoma. All patients showed a good tolerance to the treatment; until now, all patients were in local control during the follow up and one died for distant progression 6 months after radiosurgery. CONCLUSIONS: This study showed that this noninvasive technique, based on eye position control, is appropriate and can contribute to the success of LINAC-based stereotactic radiotherapy. A millimetric safety margin to the clinical target volume was adequate to take account for the organ movement. All patients treated till now showed a good local control; failures in the disease control were due to metastatic spread.

Photon-based High-dose Single-fraction Radiosurgery, an Effective Treatment Modality for Large and Posterior Uveal Melanoma.

BACKGROUND/AIM: Uveal melanoma (UM) is the most common primary intraocular malignant tumor. This malignancy is frequently treated using brachytherapy, stereotactic radiotherapy, or proton therapy. The objective of this study was to assess the role of stereotactic radiosurgery in the treatment of large and posterior UM. PATIENTS AND METHODS: From January 2014 to July 2021, we treated 65 patients (median age=71 years; range=31-89 years) affected by UM. Inclusion criteria were Eastern Cooperative Oncology Group (ECOG) performance status (PS) ≤2, life expectancy >6 months, tumor thickness >10 mm, diameter >16 mm or posterior UM. The treatment was delivered with a True Beam™ LINAC with arc modulation technique. All patients received 27 Gy in one fraction (biological effective dose ≈100 Gy, assuming an α/ß of 10). RESULTS: The median follow-up was 36 (range=3-90) months. Acute toxicities were reported in 14 patients, whereas late toxicity occurred in 45 (69.2%). Fifteen patients (23.0%) underwent enucleation: eight (12.3%) for failure of local control and seven (10.7%) for late treatment co-morbidities. The 5-year local control, and progression-free, metastasis-free, enucleation-free, and overall survival rates were 80%, 43%, 62%, 65% and 56%, respectively. In multivariate analysis, tumor dimensions significantly influenced survival [larger basal diameter: progression-free [hazard ratio (HR)=2.42] and overall (HR=2.61) survival; greater thickness: overall survival (HR=2.36)]. In multivariate analysis, patients without local control had a higher risk of distant metastasis (HR=3.25). CONCLUSION: Stereotactic radiosurgery offers an effective and safe approach for selected cases of UM due to the satisfactory results in terms of local control, eye conservation and survival.

Quality of Life, Depression, and Anxiety in Patients with Uveal Melanoma: A Review.

The aim is to summarize current knowledge on both QoL and depressive/anxious symptoms in patients with UM, including studies on the effect on QoL and psychological status of genetic testing related to the risk of metastatic disease. A review from the last 25 years by using the databases "PsycInfo," "Medline," and "Science Direct" was performed. As a total result, eighteen papers were retrieved. Eight studies (44.4%) used a prospective design methodology: two were retrospective observations (11.1%), three were cross-sectional observational studies (16.6%), and three (16.6%) were naturalistic follow-up studies. One trial was conducted with a case-control design (5.5%), and one was a methodological paper (5.5%). The number of subjects included in the studies ranged widely, between 7 and 842 (mean: 152.1 ± 201.3), for a total of 2587 patients, 1306 males (50.5%) and 1281 females (49.5%). The mean age of subject enrolled was 61.3 ± 4.1 years. Twenty-six different scales, questionnaires, or interviews were utilized. No significant differences in QoL between radiotherapy and enucleation emerged. Genetic testing did not significantly affect QoL or psychological status.

EFFECTS OF A MODIFIED VITRECTOMY PROBE IN SMALL-GAUGE VITRECTOMY: An Experimental Study on the Flow and on the Traction Exerted on the Retina.

PURPOSE: Thorough this experimental study, the physic features of a modified 23-gauge vitrectomy probe were evaluated in vitro. METHODS: A modified vitrectomy probe to increase vitreous outflow rate with a small-diameter probe, that also minimized tractional forces on the retina, was created and tested. The "new" probe was created by drilling an opening into the inner duct of a traditional 23-gauge probe with electrochemical or electrodischarge micromachining. Both vitreous outflow and tractional forces on the retina were examined using experimental models of vitreous surgery. RESULTS: The additional opening allowed the modified probe to have a cutting rate of 5,000 cuts per minute, while sustaining an outflow approximately 45% higher than in conventional 23-gauge probes. The modified probe performed two cutting actions per cycle, not one, as in standard probes. Because tractional force is influenced by cutting rate, retinal forces were 2.2 times lower than those observed with traditional cutters. CONCLUSION: The modified probe could be useful in vitreoretinal surgery. It allows for faster vitreous removal while minimizing tractional forces on the retina. Moreover, any available probe can be modified by creating a hole in the inner duct.

The Argus II Retinal Prosthesis: 12-month outcomes from a single-study center.

PURPOSE: To study the anatomic and functional outcomes of Argus II Retinal Prosthesis System implantation in patients with retinitis pigmentosa. DESIGN: Interventional case series. METHODS: The study population included 6 patients with visual acuity no better than light perception. After the Argus II Retinal Prosthesis System was implanted, complications and anatomic and functional results were studied. The main outcome measures were mobility, square localization, direction of motion, grating visual acuity, and Goldmann visual field, all of which were assessed. Optical coherence tomography was performed. RESULTS: Implantation of the Argus II Retinal Prosthesis System was safely performed in all patients. One patient experienced postoperative elevation in intraocular pressure, which was controlled medically. In 1 patient, moderate detachment of the choroid occurred postoperatively, and it resolved spontaneously. One patient withdrew from the study. Wound dehiscence, endophthalmitis or retinal detachment was not observed. All patients were able to locate a bright light on the ceiling and a dark line on the floor after the surgery. Performance in square localization tests improved in 4 patients, and direction of motion improved in 3 patients. One patient achieved grating visual acuity. Goldmann visual field test results improved in all patients. CONCLUSIONS: The patients showed improvement in visual tasks after the surgery, and the device was well tolerated and functional over a 1-year follow-up period. A rigorous patient-selection process is necessary to maximize patient compliance with the rigorous follow-up testing schedule. Both patients and medical staff should be prepared for a lengthy, arduous rehabilitation process.

Optic disc pit maculopathy: the value of small-gauge vitrectomy, peeling, laser treatment, and gas tamponade.

PURPOSE: To report the outcome of 10 patients with optic pit maculopathy (OPM) and evaluate the role of small-gauge vitrectomy, gas endotamponade, and additional laser photocoagulation treatment. METHODS: We retrospectively investigated 10 patients who underwent small-gauge, sutureless vitrectomy for OPM, detachment of the posterior hyaloid, internal limiting membrane (ILM) peeling, endolaser photocoagulation on the temporal margin of the optic disc, and gas tamponade. Preoperative and postoperative best-corrected visual acuity (BCVA) was recorded and optical coherence tomography (OCT) imaging was performed. RESULTS: Seven out of 10 patients gained at least 2 lines of vision; 2 patients gained 1 line of vision. Visual improvement occurred more than 3 months after surgery. One myopic patient developed a macular hole postoperatively, resulting in a poor functional result even though complete retinal attachment was achieved. The functional outcome did not always correlate well with the OCT imaging, in which complete retinal reattachment was observed in 5 out of 10 eyes. CONCLUSIONS: The therapeutic approach should include both small-gauge vitrectomy and ILM peeling to relieve vitreoretinal traction, as well as laser photocoagulation of the temporal margin of the optic disc in order to prevent vitreous fluid from entering the subretinal/intraretinal space. In addition, the patients should be told that visual recovery can take a long time.

Colored perfluorocarbon liquids as novel intraoperative tools.

BACKGROUND: Perfluorocarbon liquids (PFCLs) are used as intraoperative tools to stabilize the retina during vitreoretinal surgeries. Their use would be much facilitated if PFCLs were colored and not transparent. We describe the development of a colored PFCL for vitreoretinal surgeries. METHODS: Perfluorohexyloctan (F6H8) was colored by adding a blue, biocompatible anthraquinone dye, and then mixed with perfluorodecalin (PFD) or perfluorooctane (PFO) at different volume percentages. The thus-obtained colored PFCLs were incubated with lens, lens capsule, vitreous body, and retina of enucleated porcine eyes for staining purpose and analyzed microscopically. To analyze possible interactions between colored PFCLs and silicone oil, colored PFCLs were exchanged to BSS and silicone oil respectively in enucleated pig eyes. RESULTS: By mixing different volume% of colored F6H8 with perfluorodecalin (PFD) or perfluorooctane (PFO), colored PFCLs of different density and staining intensity were obtained. Cornea, lens, lens capsule, vitreous, and retina showed no signs of staining after incubation with colored PFCLs for 10 min. Colored PFCLs were transparent despite intense coloring, thus allowing a clear visibility of the underlying tissue. Immediately after instillation of silicone oil, the colored PFCL bubble was well-defined, and colored PFCL was easily aspirated. After 5 minutes reaction time, considerable diffusion of the dye from the PFCL bubble into the silicone oil was observed. CONCLUSIONS: The staining intensity can be varied according to the volume% of the colored F6H8 phase. Colored PFCL is clearly visible when installed in the vitreous cavity of a pig eye, and can easily be removed. It does not stain the intraocular tissues in pig eyes. Colored PFCL can be exchanged with silicone oil. But a time-dependent diffusion of the dye into the silicone oil was observed in pig eyes, indicating that the contact should be limited.

Comparative study between a standard 25-gauge vitrectomy system and a new ultrahigh-speed 25-gauge system with duty cycle control in the treatment of various vitreoretinal diseases.

AIM: To compare a standard 25-gauge vitrectomy system with a new ultrahigh-speed (UHS) 25-gauge system with duty cycle control for pars plana vitrectomy. METHODS: In this prospective, controlled clinical trial, 120 patients (divided into 2 groups of 60 patients) underwent a 3-port pars plana vitrectomy for the treatment of epiretinal membranes, macular holes, retinal detachment, and complications of diabetic retinopathy. Evaluations were performed preoperatively, intraoperatively, on the first 3 postoperative days, and at 1 week, 1 month, and 3 months. Main outcome measures were vitrectomy time, induction of posterior vitreous detachment, and intra- and postoperative complications. Vitrectomy time included retinal manipulation, but did not include wound opening and closure. RESULTS: The duration of surgery was significantly different between the groups. Patients in the new UHS 25-gauge group had a significantly shorter duration of vitrectomy time (P < 0.0001). Mean overall vitrectomy time was 1,583.7 ± 875.4 seconds (26 minutes) in the standard 25-gauge group and 1,106.3 ± 575.9 seconds (18 minutes) in the UHS 25-gauge group. Twenty-nine patients (48.3%) in the standard group and 27 patients (45.0%) in the UHS group experienced induction of posterior vitreous detachment. Thirteen patients (21.7%) in the standard 25-gauge group and 1 patient (1.7%) in the new UHS group had intraoperative iatrogenic retinal breaks. CONCLUSION: The new-generation UHS 25-gauge system may provide a new paradigm of high-flow, smaller-diameter instrumentation, thus increasing the efficiency of the small-gauge technique and the safety of the surgery.

Surgical results of heavy silicone oil HWS-45 3000 as internal tamponade for inferior retinal detachment with PVR: a pilot study.

PURPOSE: To report the results of a prospective pilot study using a new heavy agent, HWS-45 3000, as endotamponade in complicated inferior retinal detachment. METHODS: Ten consecutive patients satisfying the enrolment criteria were studied. Inclusion criteria was the presence of inferior retinal detachment complicated by PVR grade C2 or more (according to Retina Society classification) or retinal detachment due to penetrating ocular trauma or giant retinal tears. Heavy silicone oil was injected at the end of surgery after peeling of retinal membranes and/or retinotomy. Follow-up protocol visits were scheduled at 1 day, 1 week, 1 month, and 2 months after the initial surgery and 1 week, 1 month and 6 months after HWS-45 3000 removal surgery. Oil removal was planned after about 2 months from the main surgery. RESULTS: At the 1-month protocol visit, eight eyes presented retinal reattachment and two eyes presented a retinal detachment not involving the posterior pole. Visual acuity ranged from 2.2 logMAR to 1.0 (mean: 1.45, SD: 0.53). Oil removal surgery was scheduled about 60 days postoperatively. All eyes required additional endolaser treatment during removal surgery, and four eyes epiretinal membrane peeling. In two eyes that presented retinal detachment not involving the posterior pole, tamponading with 5700 cSt silicone oil was necessary. At 3- and 6-month protocol visits, all patients presented retina reattached; two eyes had silicone oil as internal tamponade. CONCLUSION: From our first results, HWS-45 3000 appears to be a well-tolerated heavy oil suitable for the treatment of complicated inferior retinal detachment.

Incidence of retinal detachment after small-incision, sutureless pars plana vitrectomy compared with conventional 20-gauge vitrectomy in macular hole and epiretinal membrane surgery.

PURPOSE: The purpose of this study was to evaluate the incidence of retinal detachment (RD) after a small-incision, sutureless vitrectomy compared with conventional 20-gauge vitrectomy in macular hole and epiretinal membrane surgery and to investigate the clinical features and possible causative agents. METHODS: The authors performed a computerized database analysis to retrospectively identify all patients who underwent vitrectomy at our institution between March 2001 and March 2009 for epiretinal membrane and macular hole. The authors further investigated the clinical features of patients who showed RD within 6 months postoperatively in the study eye. The incidence rate and clinical features of the affected eyes were analyzed. RESULTS: During the study period, 2,432 vitrectomies were performed for epiretinal membrane and macular hole. The incidence of RD was 1.7% (31 of 1,862) after sutureless 25- or 23-gauge vitrectomy and 1.2% (7 of 570) after conventional 20-gauge vitrectomy. The difference was not statistically significant. Moreover, the difference between 25-gauge surgery (28 of 1,580) and 23-gauge surgery (3 of 282) was not statistically significant. In 9 of 38 cases (24%), the RD was probably attributable to the underlying pathology (e.g., an unclosed macular hole and reopening of preexisting retinal tears). Twenty-one eyes (76%) presented new retinal tears that were not related to the sclerotomies in both groups. CONCLUSION: The incidence of RD after macular surgery is not increased in small-gauge, sutureless vitrectomy compared with the standard 20-gauge procedure. In most cases, the RD is not caused by the surgical technique itself but caused by new retinal breaks.

Retinal detachment after small-incision, sutureless pars plana vitrectomy: possible causative agents.

BACKGROUND AND PURPOSE: To identify possible agents causing retinal detachment following small-incision, sutureless vitrectomy. METHODS: Computer-based, retrospective analysis to identify all patients who had undergone small-incision sutureless vitrectomy and presented retinal detachment (RD) in the study eye within 6 months postoperatively. The clinical charts of these patients were reviewed. RESULTS: The investigation involved 2,598 small-incision, sutureless vitrectomies. Thirty-seven eyes presented subsequent RD. Indications for sutureless vitrectomy were idiopathic epiretinal membrane (n = 15), idiopathic macular hole (n = 15), recurrent macular hole (n = 1), rhegmatogenous retinal detachment (n = 5) and vitreous haemorrhage due to proliferative diabetic retinopathy (PDR) (n = 1). The median time between sutureless vitrectomy and RD presentation was 51 days (range 11-173 days); mean 59 days (SD 46.5). In 14 eyes (38%), the RD was most likely due to the underlying pathology (e.g., unclosed macular hole, reopening of pre-existing retinal tears, worsening of PDR). Twenty-three eyes (62%) presented with new retinal tears that were not in the proximity of the sclerotomies. CONCLUSION: In most cases, the RD was not caused by the sutureless technique itself, but was most likely due to the underlying pathology, or due to new retinal tears that were not in the proximity of the sclerotomies.

Heavy silicone oil (Densiron-68) for the treatment of persistent macular holes: Densiron-68 endotamponade for persistent macular holes.

PURPOSE: To evaluate the efficacy and safety of the use of Densiron-68 as intraocular endotamponade for the treatment of persisting macular holes (persistent MHs). METHODS: Retrospective interventional case study on 23 consecutive eyes showing persistent MHs after unsuccessful primary surgery that underwent retreatment with pars plana vitrectomy and Densiron-68 filling. The main outcome measures were: anatomic closure evaluated with optical coherence tomography (OCT), final best-corrected visual acuity (BCVA), and postoperative complications. RESULTS: A total of 23 patients (52-88 years) were studied. Pre-operative OCT showed full-thickness MH (mean size 560 microm) in all patients. Densiron-68 was left in situ for 1.5-3 months. Final follow-up time was 12 months after the last surgery. Postoperative OCT showed the complete closure of the PMH in 20 of 23 eyes. Pre-operative BCVA ranged from 20/200 to 20/630 (1.50-1.00 logMAR, mean 1.14). Final postoperative BCVA ranged from 20/30 to 20/400 (0.18-1.30 logMAR, mean. 0.61). Nineteen eyes (82%) showed a significant increase in visual acuity by at least three lines: 11 (47%) patients gained at least four lines. Three eyes remained unchanged (13%). One case deteriorated by two lines (4%). No major complications were recorded. CONCLUSIONS: Retreatment with Densiron-68 filling was safe and achieved encouraging anatomic and functional results.

A multimodal approach to the treatment of bilateral choroidal metastases from thyroid carcinoma.

A 58-year old man, affected by metastatic thyroid carcinoma, experienced a progressive bilateral visual impairment. Ophthalmic examination revealed the presence of a choroidal mass with an associated exudative retinal detachment in both eyes. Twelve years before, a diagnosis of metastatic thyroid carcinoma had been established and the patient had been subject to several therapeutic procedures.In May 2007, he received a radiotherapy treatment to the left eye with an episcleral plaque and bilateral bulbar injection of bevacizumab. The patient had a rapid and stable visual acuity recovery. Twenty months after treatment, the lesion treated with radiotherapy was still stable whereas the contra-lateral lesion had evolved and determined a vitreal hemorrhage.

Injection of intravitreal bevacizumab (Avastin) as a preoperative adjunct before vitrectomy surgery in the treatment of severe proliferative diabetic retinopathy (PDR).

PURPOSE: To evaluate the use of preoperative intravitreal bevacizumab (IVB) in patients undergoing pars plana vitrectomy (PPV) for complications of proliferative diabetic retinopathy (PDR). METHODS: We studied 22 patients with severe PDR. A preoperative complexity score (CS) was recorded. Eleven eyes were treated with IVB, 1.25 mg, 5-7 days before PPV (group 1), and 11 eyes underwent direct PPV (group 2). Surgical time and intra-operative manoeuvres were recorded. Main outcome measure was feasibility of surgery, secondary goal was the visual and anatomic outcome at 6 months. RESULTS: The average CS was 5.5, and was similar in the two groups. Mean surgical time was 57 minutes in group 1 vs 83 minutes in group 2; mean tool exchanges was 27 vs 53, intraoperative bleeding 5 vs 15, endodiathermy 2 vs 9. No complications were recorded after IVB. Mean pre-operative BCVA was 1.87 logMAR in group 1 and logMAR 2.04 in group 2. Mean pre-operative BCVA was 1.87 logMAR in the bevacizumab group and 2.04 logMAR in group 2, not significantly different (p = 0.7). Mean post-operative BCVA at 6 months was 0.88 logMAR in group 1 and logMAR 2.01 in control group 2, significantly different (p = 0.01). Post-operative BVCA improved in bevacizumab group from pre-operative value (p = 0.15), while in control group there was non-significant increase (p = 0.96). Anatomical attachment was achieved in 11 patients in group 1 vs nine patients in group 2. CONCLUSIONS: IVB administered prior to vitrectomy was well tolerated and reduced active neovascularization, thus facilitating PPV.

A new heavy silicone oil (HWS 46-3000) used as a prolonged internal tamponade agent in complicated vitreoretinal surgery: a pilot study.

PURPOSE: To report the results of a prospective pilot study using a new heavy agent, HWS 46-3000, as long-term endotamponade in complicated retinal detachment. METHODS: Thirty-two consecutive patients were enrolled in the study. Indications for enrollment included retinal detachment with proliferative vitreoretinopathy arising from inferior or posterior tears. The patients underwent pars plana vitrectomy, membrane peeling, and HWS 46-3000 filling. Follow-up examinations were scheduled at 1 day to 7 days and 1 month to 3 months after initial surgery and 7 days and 1 month to 6 months after endotamponade removal. RESULTS: At baseline examination, mean best-corrected Snellen visual acuity was 2.44 logarithm of the minimal angle of resolution (logMAR). HWS 46-3000 was removed after 45 days to 96 days. Initial retinal reattachment was achieved in all eyes. HWS 46-3000 endotamponade was associated with a success rate of 84.6% with a single surgery and an overall success rate of 100% at 6 months with the second operation and conventional silicone oil endotamponade. At 6 months, mean best-corrected visual acuity was +1.09 logMAR (P < 0.0001). Complications were posterior subcapsular cataract formation (100%), membrane formation (3 eyes, 9%), and increased intraocular pressure (1 eye). Emulsification and intraocular inflammation were not observed. CONCLUSION: HWS 46-3000 was well tolerated, effective in the inferior quadrants with a low incidence of membrane development. The main complication was the high rate of tamponade-related cataract formation.

Sutureless 25-gauge vitrectomy for idiopathic macular hole repair.

BACKGROUND: We investigated the feasibility and safety of a 25-gauge, transconjunctival sutureless vitrectomy system for macular hole repair. METHODS: Eighty-four eyes of 77 consecutive patients with idiopathic macular hole were operated on using a transconjunctival sutureless 25-gauge vitrectomy system. A complete vitrectomy was performed using triamcinolone acetonide to visualize the vitreous gel and to remove the posterior vitreous cortex. The macular hole was covered with autologous whole blood, and the internal limiting membrane (ILM) was stained with indocyanine green. The ILM was peeled and a fluid-air exchange performed. The globe was filled with gas, and the patient was kept in a prone position for 1 week. Surgery-related complications, macular hole closure on optical coherence tomography (OCT) and visual outcome were evaluated. RESULTS: No intra- or postoperative complications were recorded. It was noted in particular that sclerotomies did not require sutures. No postoperative hypotony or endophthalmitis was observed. OCT showed macular hole closure in 93% of the cases. The median preoperative best-corrected visual acuity was 20/200 and improved significantly (p<0.05) to a median best-corrected visual acuity of 20/67 (median follow-up 6.5 months). CONCLUSION: A 25-gauge transconjunctival sutureless vitrectomy, visualization of the vitreous with triamcinolone acetonide, protection of the macular hole with autologous whole blood and staining of the ILM using indocyanine green are safe and efficient techniques for macular hole repair.

Modified incision in 25-gauge vitrectomy in the creation of a tunneled airtight sclerotomy: an ultrabiomicroscopic study.

BACKGROUND: The standard straight incision for 25-gauge vitrectomy may not close well at the end of surgery with post-operative hypotony. To overcome incompetent wound closure, oblique insertion of the trocars has been suggested. More recently we have developed an oblique incision. which is parallel to the scleral fibres instead of perpendicular and therefore avoids cutting. The aim of this study was to compare the effectiveness of the different incisions and to investigate their behaviour with the UBM. METHODS: 45 patients affected by macular holes were operated; in 15 eyes using oblique-parallel insertion (OPAI), in 15 oblique-perpendicular (OPEI) and in 15 straight incision (SI). Patients underwent UBM examinations 1 day, 1 week, 1 month p.o. RESULTS: OPAI was airtight after the removal of 25 g cannulas. UBM examination 1 day post-operatively (p.o) showed the 45 sclerotomies were well healed with perfect apposition of the internal wound lips. 39 sclerotomies were undetectable, 6 slightly evident. With OPEI the incisions were airtight at the end of surgery. At the 1 day p.o. UBM examination the 45 sclerotomies were well-healed but a minimal gape was clearly visible in all of them, 3 eyes showed peripheral cilio-choroidal (CCD) detachment, which was resolved after 7 days although the gape was still evident. At 1 month p.o. examination the gape was not detectable in 20 sites, evident in 25. With SI at the end of the surgery conjunctival bleb formation was detected in 10 cases, air-gas refilling was performed in 7 eyes and 3 sclerotomies were sutured. At 1 day p.o. hypotony was recorded in 5 patients, recovering at the 7 day follow-up. At the 1 day p.o. UBM examination showed a significant gape in all sites, weak vitreous entrapment was shown in 36, subconjunctival fluid in 4, CCD in 7. At the 7 day UBM the CCD had disappeared in 4 and was reduced in 3. At the 1 month p.o. the sclerotomy defect was still detectable but other complications were no longer evident. CONCLUSIONS: OPAI achieved the quickest and most complete sealing since the 1st day p.o without complications, therefore it could be safer when performing 25-g vitrectomy with extensive manipulation.

Successful treatment of persistent macular holes using "heavy silicone oil" as intraocular tamponade.

BACKGROUND: Silicone oil tamponade has been suggested in the treatment of persistent macular hole, but visual outcome is often poor. We describe two patients who underwent reoperation for persistent macular hole using "heavy silicone oil" (HSO) tamponade. METHODS: Two patients who underwent vitrectomy, removal of the posterior vitreous cortex, peeling of the internal limiting membrane, and long-acting gas tamponade had persistent macular hole 3 months after surgery. The patients underwent reoperation using an HSO (Oxane Hd, Bausch & Lomb) as internal tamponade. This tamponade did not require postoperative posturing and was removed after 3 months. Optical coherence tomography (OCT) was performed, and visual outcome was determined. RESULTS: OCT images showed that the HSO bubble conformed well with the retinal surface in the foveal region. Closure of the macular hole was achieved in both patients. Visual acuity increased from 20/100 to 20/40 in Patient 1 and from 20/600 to 20/100 in Patient 2. CONCLUSION: HSO can be a useful tool in the treatment of persistent macular hole. OCT images showed that the tamponade was effective in the upright position in the foveal region. OCT allowed determination of the time of tamponade removal according to the anatomical stage of hole closure.