Marco Codenotti

A novel spectral-domain optical coherence tomography model to estimate changes in vitreomacular traction syndrome

PurposeTo analyze the course of eyes with vitreomacular traction (VMT), and to find by optical coherence tomography (OCT) possible correlations between vitreomacular interface area changes and the chance of spontaneous VMT resolution.MethodsRetrospective analysis of all consecutive patients presenting with VMT over a 24-month period. We introduced a novel OCT evaluation model to assess the vitreomacular interface area. Central foveal thickness (CFT) and best-corrected visual acuity (BCVA) were also analyzed throughout follow-up.ResultsTwenty-six eyes of 18 symptomatic patients were followed for 12.9 ± 4.8 months. Eyes were subdivided into groups according to their clinical course. Six eyes (23%) had a spontaneous resolution of the VMT (group A), and the interface area before its occurrence (39565 ± 26409 μm2) was smaller than at study entry (99434 ± 38819 μm2; p = 0.03). The interface area did not significantly change throughout follow-up in the group that underwent surgery (group B, 11 eyes) and in the group that remained overall stable (group C, 9 eyes). At baseline, the interface area was smaller in group A compared to groups with non-resolved VMT (mean values of group B and C together) (785095 ± 920721 μm2; p = 0.002). CFT and BCVA did not significantly change in any of the studied groups. Vitreomacular interface area of 101002 μm2 was identified as the threshold value separating the spontaneous VMT resolution group from the group with non-resolved VMT (p < 0.001).ConclusionsThe more the vitreomacular interface area reduced over time, the higher was the chance of spontaneous VMT resolution. An area below 101002 μm2 was the threshold value indicating a higher chance of spontaneous release of VMT.

Vitreomacular traction syndrome: a comparison of treatment with intravitreal plasmin enzyme vs spontaneous vitreous separation without treatment

PurposeTo evaluate the effects of intravitreal autologous plasmin enzyme (APE) in patients with focal vitreomacular traction (VMT).MethodsAPE was obtained by incubation of patient-derived purified plasminogen with streptokinase, and intravitreally injected 5–12 days later. Twenty-four hours after injection, in case of incomplete VMT release, a pars plana vitrectomy was performed. The hyaloid internal limiting membrane adherence and removal of the posterior hyaloid were intraoperatively evaluated.ResultsThirteen patients were recruited. During preparation of APE, five patients had spontaneous release of VMT. Eight patients received APE injection (2 IU). In five patients, spontaneous resolution of VMT occurred before APE administration. Twenty-four hours after injection, persistence of VMT was detected in all the eight treated patients. Best-corrected visual acuity was 0.51±0.37 LogMAR at baseline, improving to 0.23±0.14 LogMAR at 6 months (P=0.002). Foveal thickness was 464±180 μm at baseline, reducing to 246±59 μm at 6 months (P<0.001). Hyaloid was intraoperatively judged ‘partially detached’ in seven cases and ‘totally detached’ in one case. Hyaloid peeling was evaluated ‘easy’ in six eyes and ‘very easy’ in two eyes.ConclusionsIn the current study, there was a large percentage of spontaneous resolution of VMT before an APE administration. A single intravitreal APE injection seems insufficient to induce a complete posterior vitreous detachment in these patients.

Anterior chamber migration of dexamethasone intravitreal implant (Ozurdex®) through basal iridectomy (Ando) in a pseudophakic patient.

Purpose Intravitreal implantation of dexamethasone implant (Ozurdex®) is being widely used for the treatment of macular edema (ME) after branch or central retinal vein occlusion, diabetic ME, and persistent ME associated with uveitis or Irvine-Gass syndrome. We describe a complication: migration of the dexamethasone implant into the anterior chamber through basal iridectomy (Ando) in a pseudophakic patient with development of corneal edema and secondary high intraocular pressure. Methods This is a case report of migration of Ozurdex® through basal iridectomy in a pseudophakic patient with iris claw lens. Conclusions Pseudophakic patients, with a history of vitrectomy, even those with a basal iridectomy (Ando), are at high risk for migration of the Ozurdex® into the anterior chamber and development of corneal edema.

SD OCT features of dry arcuate longstanding retinal folds.

We read with interest the case report by Pierro et al (1) on spectral domain optical coherence tomography (OCT) features of dry arcuate longstanding retinal folds. The authors describe the appearance of hyperreflective lesions of the outer retina with indentation of the overlying retina which was associated with thickening of the inner limiting membrane (ILM) and vitreoretinal adhesion. We have also recently followed 13 patients with retinal folds following vitrectomy for acute rhegmatogenous retinal detachment (submitted). We have found identical outer retinal lesions that disappear over time (Fig. 1), but leave behind the inner retinal changes which signify a relative rigidity or certainly slower recovery of the inner retinal layer compared to the outer retina. Therefore, it may be the hyperreflective lesion lifting the inner retina initially, but it is probably not the outer retinal lesion which is causing the inner retinal undulation to occur in the long term. The ILM thickening and vitreoretinal adhesions would better be described as the beginnings of an epiretinal membrane or proliferative vitreoretinopathy as frequently seen in rhegmatogenous retinal detachments. This was not found in any of our cases. The authors also quote Kertes and Peyman (2) in describing previously published works of dry arcuate folds which is incorrect as this article describes 2 cases of tractional folds from a toxocara scar and another due to proliferative diabetic retinopathy. LETTER TO THE EDITOR

Ultrasound biomicroscopy of residual vitreous base after vitreoretinal surgery.

Residual vitreous base after vitreoretinal surgery was evaluated by ultrasound biomicroscopy (UBM). Twenty aphakic and pseudoaphakic patients (20 eyes) undergoing surgery for different vitreoretinal diseases were evaluated by high-frequency (50 MHz), high-resolution (50 µm) UBM, performed the day before surgery, weekly up to 1 month after surgery and then monthly. One week after surgery, the vitreous remnants were ‘hardly visible’ in 3 cases, ‘visible’ in 6 cases and ‘highly visible’ in 11. At the end of the follow-up (2.2 months), the ‘hardly visible’ cases increased to 6 and the ‘visible’ cases to 12, while the ‘highly visible’ cases decreased to 2. UBM demonstrated that vitreous base remnants were present in spite of accurate surgery; a spontaneous volume reduction of vitreous was observed during the follow-up.

Intravitreal Ranibizumab for myopic choroidal neovascularization after pars plana vitrectomy and silicone oil tamponade.

Purpose To report on intravitreal Ranibizumab for intervening myopic choroidal neovascularization (CNV) in a case of retinal detachment successfully repaired with pars plana vitrectomy and silicone oil tamponade. Methods Intravitreal ranibizumab was performed in a 67-year-old woman with CNV complicating pathologic myopia. The patient had previously undergone vitrectomy and silicone oil tamponade for retinal detachment. Results At 2 months from intravitreal ranibizumab, best-corrected visual acuity (BCVA) improved from count fingers to 20/100, and intraocular pressure (IOP) was 16 mm Hg. Fluorescein angiography (FA) and spectral-domain optical coherence tomography (SD-OCT) showed resolution of late leakage and subretinal/intraretinal fluid, respectively. Conclusions Administration of intravitreal anti-VEGF in patients with silicone oil as intraocular tamponade may represent an intriguing treatment option. Our results suggest that intravitreal injections of Ranibizumab may lead to a rapid improvement in both functional (BCVA) and morphologic (FA and SD-OCT) parameters of CNV activity, without significant rise in IOP, in eyes with silicone oil as intraocular tamponade.

Microincision 25G pars plana vitrectomy with peeling of the inner limiting membrane and air tamponade in idiopathic macular hole.

Purpose To evaluate the success of a mini-invasive technique for operation of idiopathic macular hole (IMH). Methods We retrospectively examined 29 patients (30 eyes) in whom 25-G pars plana vitrectomy (PPV), peeling of the inner limiting membrane (ILM), and application of air tamponade were performed. The group of the patients included 7 males and 22 females (76%), age range 57-79 years (median 70). The follow-up period was 3-47 months (median 17). Results Pars plana vitrectomy was indicated only in the stages of full-thickness macular hole. Prior to operation, 13 eyes (43%) were in stage 2, 15 eyes (50%) in stage 3, and 2 eyes (7%) in stage 4. The IMH healed in 28 eyes after operation. Persistence of IMH occurred in 2 eyes (7%). After subsequent reoperation with extension of the peeling zone of the ILM and gas tamponade (with 10% C3F8), these macular holes also healed (100%). Prior to carrying out PPV, best-corrected visual acuity (BCVA) ranged between 20/40 and 20/500 (median 20/125). At the end of the follow-up period, BCVA was improved to 20/40 (median). The change in the final BCVA compared to the initial visual acuity was statistically significant (p = 0.008; Wilcoxon). Conclusions The 25-G PPV with peeling of the ILM and air tamponade is an effective technique and presents no increased risks in comparison with routine procedures. The main benefit of the intervention is its good tolerance by the patient, particularly with respect to painfulness and postoperative irritation.

Simultaneous vitreous hemorrhage and branch retinal artery occlusion after prepapillary arterial loop rupture.

Prepapillary arterial loops are rare benign congenital vascular anomalies that may be complicated by vitreous hemorrhage and branch retinal artery occlusion (BRAO). We describe the first case in the literature of simultaneous occurrence of both these complications in the same eye of a patient with a bilateral prepapillary arterial loop, successfully treated with vitrectomy.

Reply to Grzybowski and Ascaso

Sir, We thank Drs Grzybowski and Ascaso1 for their interest in and comments on our recent article.2 We agree that in our paper there is a lack of details concerning the statistical tests used (which were omitted for the sake of brevity). In the study, we proved that each variable group was normally distributed using the Kolmogorov-Smirnov normality test. Then we applied the ANOVA for repeated measures test, which best fitted for our analysis. Please note, the Kruskal-Wallis test is valuable only for a two-group comparison. We also agree that the lack of a control group is crucial, and this was acknowledged as a limitation of our study. We also acknowledged the unmasked design of the study as a limitation of our analysis. Regarding the evaluation of posterior hyaloid peeling, our method to describe the intrasurgical findings has been already published by Azzolini et al3 in a study investigating autologous plasmin enzyme for diabetic macular oedema, and, to our knowledge, no other classification systems are available in the literature. In the conclusion section, we stated that a single intravitreal autologous plasmin enzyme injection seemed to be insufficient to induce a complete posterior vitreous detachment in patients affected by focal vitreomacular traction syndrome, as in our case series, we did not obtain any complete posterior vitreous detachment with a single injection. We thank the authors for the opportunity to clarify this important aspect, which we do not find contradictory. As per our ethical committee approved protocol (reported in the Methods section), we were allowed to perform just one single intravitreal injection for each study patient, with a 24-hour waiting time before vitrectomy. Although we could not ascertain if a greater time gap could have influenced the rate of posterior vitreous detachment occurrence, we remarked that the single injection appeared as a useful tool in vitreoretinal surgery by obtaining an easier-to-peel posterior hyaloid. Finally, during the revision process of our paper, we preferred to exclude the comparison of our results with the MIVI-IIT study,4 as the MIVI-IIT study has a very different study design and uses a different drug. Particularly, we believe that our impossibility (per protocol) to re-inject patients preclude any comparison between the two studies.

Scleral buckling dislocation mimicking glaucoma progression.

Purpose. To report a case of scleral dislocation mimicking glaucoma progression. Methods. Interventional case report. Results. A 71-year-old man was referred for glaucoma surgery in his right eye because of perimetry defect progression and uncontrolled intraocular pressure despite maximal medical therapy. A scleral buckling procedure in his right eye was previously performed for rhegmatogenous retinal detachment. At the time of presentation, a visible protruded sponge buckle element was noted at ocular inspection, without any sign of infection. The buckle element was posteriorly in contact with the optic nerve and anteriorly protruding under intact conjunctiva. We eventually managed for its removal via upper eyelid orbitotomy. Visual field lesions were unchanged on every follow-up visit. Conclusions. This case report describes severe permanent optic nerve damage due to previous misdiagnosis of a rare complication of scleral buckling surgery. Our surgical solution appears to be a safe and successful approach for this ocular disorder, also able to stabilize visual function and interrupt disease progression.