Characterization of Epiretinal Proliferation in Full-Thickness Macular Holes and Effects on Surgical Outcomes.

PURPOSE: Epiretinal proliferation is a distinct clinical entity from epiretinal membrane that classically is associated with lamellar macular holes, but its prevalence and association with full-thickness macular holes (FTMH) have not been well described. We characterized macular hole-associated epiretinal proliferation (MHEP) and its effects on long-term surgical outcomes. DESIGN: Multicenter, interventional, retrospective case-control study. PARTICIPANTS: Consecutive eyes that underwent surgery for FTMH with a minimum of 12 months follow-up. METHODS: All eyes underwent pars plana vitrectomy, removal of any epiretinal membranes, and gas tamponade, with or without internal limiting membrane (ILM) peeling. Spectral-domain OCT imaging was obtained before and after surgery. MAIN OUTCOME MEASURES: Improvement in visual acuity and single-surgery hole closure rates in eyes with, versus without, MHEP at 12 months. RESULTS: Seven hundred twenty-five charts were analyzed, and 113 patients met inclusion criteria. Of 113 eyes with FTMH, 30 (26.5%) showed MHEP. Patients with FTMH and MHEP were older (P < 0.002) and more often men (P = 0.001), and showed more advanced macular hole stages than those without MHEP (P = 0.010). A full posterior vitreous detachment was more common in eyes with MHEP (P < 0.004). Twelve months after surgery, FTMH with MHEP patients showed significantly less improvement in visual acuity (P = 0.019) with higher rates of ellipsoid and external limiting membrane defects (P < 0.05) and with a higher rate of failure to close with 1 surgery compared to FTMH without MHEP (26.7% vs. 4.8%; P = 0.002]). Peeling the ILM was associated with improved rates of hole closure in FTMH with MHEP (P < 0.001). Multivariate testing confirmed that the presence of MHEP was an independent risk factor for less visual improvement (P = 0.031) and for single-surgery nonclosure (P = 0.009) and that ILM peeling improved single-surgery closure rates (P = 0.026). CONCLUSIONS: We found that FTMH with MHEP showed poorer anatomic and visual outcomes after vitrectomy compared with FTMH without MHEP. Internal limiting membrane peeling was associated with improved closure rates and should be considered when MHEP is detected before surgery.

Characteristics and Outcomes of Simultaneous Bilateral Rhegmatogenous Retinal Detachments.

BACKGROUND AND OBJECTIVE: To better understand the clinical course and outcomes of simultaneous bilateral retinal detachments managed by modern vitreoretinal surgical techniques. PATIENTS AND METHODS: A retrospective review of 21 patients (42 eyes) presenting between April 2000 and June 2015 with simultaneous bilateral rhegmatogenous retinal detachments. RESULTS: Mean visual acuity (VA) improved from 20/100 at presentation to 20/40 at last follow-up (P = .01). The mean final VA for patients undergoing scleral buckle (SB) alone was 20/30 (log MAR 0.17), pars plana vitrectomy (PPV) alone was 20/40 (logMAR 0.33), and combined PPV/SB was 20/80 (logMAR 0.59) (P = .019). Primary reattachment rate in this series was 98%. CONCLUSION: In contrast to prior studies, which investigated the management of simultaneous bilateral retinal detachments primarily by SB alone, multiple treatment modalities were utilized in this study, including vitrectomy alone, and overall success of retinal detachment repair was high regardless of treatment modality chosen. [Ophthalmic Surg Lasers Imaging Retina. 2016;47:840-845.].

Subthreshold Diode Micropulse Laser: A Review.

The subthreshold diode micropulse laser is a form of non-damaging thermal laser therapy which has shown efficacy in multiple retinal conditions. The purpose of this article is to review the use of subthreshold diode micropulse laser as an emerging treatment modality for the treatment of retinal disease. The proposed mechanisms of action, safety, efficacy, recommended laser treatment parameters, and clinical applications for which the use of subthreshold diode micropulse laser has been studied will be reviewed.

MRI of blood volume with superparamagnetic iron in choroidal melanoma treated with thermotherapy.

Functional magnetic resonance imaging (MRI) with a new intravascular contrast agent, monocrystalline iron oxide nanoparticles (MION), was applied to assess the effect of transpupillary thermotherapy in a rabbit model of choroidal melanoma. 3D-spoiled gradient recalled sequences were used for quantitative assessment of blood volume. The MRI-parameters were 5/22/35 degrees (time of repetition (TR)/echo delay (TE)/flip angle (FA)) for T(1)- and 50/61/10 degrees for T(2)-weighted sequences. Images were collected before and at different times after MION injection. In all untreated tissues studied, MION reduced the T(2)-weighted signal intensity within 0.5 h and at 24 h (all p <== 0.012), whereas no significant changes were detected in treated tumors. T(1)-weighted images also revealed differences of MION-related signal changes between treated tumors and other tissues, yet at lower sensitivity and specificity than T(2). The change of T(2)-weighted MRI signal caused by intravascular MION allows early distinction of laser-treated experimental melanomas from untreated tissues. Further study is necessary to determine whether MRI can localize areas of tumor regrowth within tumors treated incompletely.

MRI of blood volume with MS 325 in experimental choroidal melanoma.

Functional magnetic resonance imaging (MRI) allows quantitative blood volume imaging in vivo at high tissue resolution. The purpose is to apply this technique for untreated and hyperthermia-treated experimental choroidal melanoma. MS 325 was used as new intravascular albumin-bound gadolinium-based contrast agent. Pigmented choroidal melanomas were established in albino rabbits. MRI was performed in 7 untreated eyes and 7 eyes treated with a Neodymium:Yttrium-Lanthanum-Fluoride-laser at 1047 nm. 3D-spoiled gradient echo pulse sequences were used to acquire T' weighted axial images. First, a set of images was collected without contrast agent. MS 325 was then injected i.v. and images were obtained within 12 min after injection. Signal intensities were measured within tumor, ciliary body, choroid, and iris and relative signal intensities were determined for these tissues in relation to vitreous. In untreated tumors, the relative signal intensity was higher after injection of MS 325 (5.61+0.70) than without MS 325 (2.90+0.33; p = 0.0002). In contrast, the relative signal intensity of treated tumors did not differ significantly before and after MS 325 (6.19+1.59 and 6.13+1.64). Histopathological sections indicated vascular occlusion in treated tumors. All other studied tissues of untreated and treated eyes showed a significant increase of relative signal intensities in the presence of MS 325. An animal model for the research on contrast agents in MRI is presented. Blood volume measurement with MS 325 was adapted for experimental choroidal melanomas. Reduced change of relative signal intensity indicates compromised blood volume after vascular occlusion in hyperthermia-treated melanoma. Further studies are needed to investigate whether this technique allows the evaluation of tumor viability following treatments.

Treatment of experimental choroidal melanoma with an Nd:yttrium-lanthanum-fluoride laser at 1047 nm.

OBJECTIVE: To evaluate the effect of a new infrared laser in the destruction of pigmented choroidal melanomas. METHODS: B16F10 melanomas were implanted in the subchoroidal space of 64 rabbits (tumor height, 2.0-4.0 mm). Laser radiation from an Nd:yttrium-lanthanum-fluoride laser (1047 nm) was delivered as a focused (beam waist, 25 micro m; irradiance, 100 kW/cm( 2)) raster-scanned transpupillary beam. To investigate melanin heating, treatment with focused light was compared with collimated light (beam waist, 2 mm; irradiance, 16 W/cm(2)). Fine-wire thermocouples were implanted at the base of 3 tumors for in vivo temperature measurements. Untreated animals were used as controls. RESULTS: Of 64 animals, 27 received a single treatment with focused 1047-nm light. The rate of complete tumor eradication was 91% (10 of 11 animals) at a dosage of 125 J/cm(2) and 75% (9/12) at 63 J/cm(2) to 87 J/cm(2). The eradication rate dropped to 25% (1 of 4) at 38 J/cm(2) or less (P<.001). Continuous tumor growth was observed in all animals treated with collimated radiation and in untreated controls. Temperature measurements indicated that tissue heating at the tumor base was more rapid at 1047 nm than at 805 nm. CONCLUSIONS: These data suggest that a single treatment with a focused, raster-scanned beam at 1047 nm may play a role in the destruction of pigmented choroidal melanoma. Focused irradiation at 1047 nm may provide more effective submillisecond heating of melanin than collimated irradiation, resulting in immediate photothermal disruption of tumor cells.

[Photodynamic therapy of pigmented choroidal melanomas in rabbits].

OBJECTIVE: To evaluate the effect of photo-dynamic therapy in the destruction of experimental pigmented choroidal melanoma using a liposomal preparation of benzoporphyrin derivative (BPD), verteporfin. METHODS: Pigmented choroidal tumors were established in 44 New Zealand albino rabbit eyes. Animals were treated with daily injections of cyclosporine. Funduscopic examinations and ultrasonography were used to follow the tumor growth. When the tumor exceeded 2 mm in thickness (tumor height ranged from 2.0 - 4.6 mm), the rabbits were divided into three groups. In the 10 rabbits in the control group, 6 were treated with laser 120 - 150 J/cm(2) for tumors with the height range of 2.1 - 3.0 mm without photo-dynamic therapy, and 4 were not treated at all. The benzoporphyrin derivative was injected intravenously (1 mg/kg) for the rabbits in treatment group I (14 rabbits) and II (20 rabbits), and 692 nm argon-pumped dye laser at different light doses 60 - 150 J/cm(2) was used to irradiate the tumors. After the treatment for 4 - 6 weeks, the rabbits were sacrificed and the therapeutic results were observed. RESULTS: In treatment group I, the irradiation dose was 60 - 80 J/cm(2) and the tumor height was < 3 mm, in comparison with that of the control group the difference being very significant (P < 0.001). In the treatment group II, the thickness of the tumor was 3.0 - 4.6 mm and the irradiation dose was > 80 J/cm(2) (P < 0.001, companed with the control group). In contrast, the tumor grew continuously in all the animals in the control group and filled most of the vitreous cavity by 2 - 3 weeks. CONCLUSION: These data suggest that photodynamic therapy have a role in the management of pigmented choroidal melanomas.

MRI of blood volume and cellular uptake of superparamagnetic iron in an animal model of choroidal melanoma.

Functional magnetic resonance imaging (MRI), using monocrystalline iron oxide nanoparticles (MION) as a new intravascular contrast agent, was adapted for a rabbit model of pigmented choroidal melanoma. Three-dimensionally spoiled gradient recalled sequences were used for the quantitative assessment of blood volume and cellular uptake. In all ocular tissues studied, MION reduced the T(2)-weighted signal intensity within 0.5 h and at 24 h (both p < 0.05) after the injection. In individual tumors, MION reduced the T(2)-weighted signal intensity by 46-78% within 0.5 h and by 24-48% at 24 h. In addition, MION increased the T(1)-weighted signal intensity in all tissues. T(2) yielded a higher sensitivity than T(1)-weighted images. Functional MRI with MION is a noninvasive technique with regard to the eye, permitting measurement of blood volume and cellular uptake of the contrast agent. Further study is necessary to determine the feasibility of this technique for the tumor diagnosis and evaluation of tumor viability following treatments.