Vitrectomy with Fovea-Sparing Internal Limiting Membrane Peeling for Myopic Foveoschisis.

Background Myopic foveoschisis is a rare form of a tractional maculopathy, which occurs in patients with elevated axial length. The contraction of the posterior hyaloid exerts tangential traction on the retinal surface with a subsequent continuous splitting of the retinal layers. Internal limiting membrane (ILM) peeling has been advocated in foveoschisis, but it has been associated with post-operative macular hole formation. We report on a modified surgical technique, which spares the fovea and may reduce the risk for macular hole formation. Methods Retrospective analysis of 6 patients with myopic foveoschisis. The mean age was 53.8 ± 12.9 years (4M, 2F) and mean myopia was - 18.3 ± 6.5 Dpt. After a 23 g pars plana vitrectomy, the ILM was peeled on the entire macular surface, except in the foveal region lest the thin foveal structures be damaged. All patients received a gas tamponnade with 23 % SF6 and maintained a face down position for 5 days. Results Mean best-corrected pre-operative visual acuity was 0.87 ± 0.56 logMAR, which increased to 0.60 ± 0.40 logMAR at the end of follow-up. The retinal thickness, as measured by optical coherence tomography, decreased from 799 ± 352 micrometers to 318 ± 60 micrometers at the end of follow-up 7.8 ± 5.7 months. No case developed a macular hole. Conclusions Vitrectomy with fovea sparing ILM peeling is a promising surgical technique, which results in an improved foveal anatomy and retinal function. Due to the sparing of the fovea, this surgical technique may reduce the risk of macular hole formation in the post-operative period.

Early changes in optic coherence tomography in a child with laser pointer maculopathy. / Cambios precoces en la tomografía de coherencia óptica en un niño con maculopatía inducida por puntero láser.

CASE REPORT: A 9-year-old boy referred due to visual loss in his right eye after playing with a laser pointer. In the first visit (12hours later) visual acuity (VA) was 0.15. A hypopigmented lesion was present in the fovea, and optic coherence tomography (OCT) showed vertical hyper-reflective bands. In the last visit (6 months later), VA had improved to 0.5, and OCT showed a well-defined area of outer retinal layer disruption. DISCUSSION: An inadequate use of laser pointers can induce severe and permanent visual loss.

Retinal Injury Secondary to Laser Pointers in Pediatric Patients.

This case report describes 4 male children (age, 9-16) who had laser-related retinal injury to the macula of 1 eye or both eyes due to the mishandling of the laser pointer devices at a single vitreoretinal clinical practice. The presenting symptoms associated with laser pointer injury include central vision loss, central scotoma, and metamorphopsia. Clinical findings of laser-related retinal injury include reduced visual acuity, disruption of the photoreceptor ellipsoid zone, retinal pigment epithelium atrophy, and choroidal neovascular membrane formation. Disruption of the foveal ellipsoid zone (photoreceptor inner segment/outer segment layer) is the most common finding on optical coherence tomography imaging. Three patients had potential irreversible vision loss. Laser pointers are readily available and appropriate use of laser pointers in the pediatric population must be emphasized due to the potential irreversible retinal injury. Health professionals, school teachers, and parents should raise public awareness of this emerging public health issue by educating children about the dangers of laser pointers. Laser pointer devices among children should be discouraged and limited due to the possibility of permanent harm to themselves and others. Legislation and laws may be required to better control the sale and use of these devices.

Foveal Damage Due to Subfoveal Hemorrhage Associated with Branch Retinal Vein Occlusion.

To investigate the functional and morphologic prognoses of eyes with subfoveal hemorrhage from acute branch retinal vein occlusion (BRVO), and to examine the effect of intravitreal ranibizumab injection (IVR) on these prognoses, we assessed 81 eyes with acute BRVO, of which 38 did not receive IVR [IVR(-) group], and 43 were treated with IVR [IVR(+) group] for macular edema. The foveal morphologic changes were examined via optical coherence tomography (OCT). At initial examination, 63 eyes exhibited subfoveal hemorrhage. At final examination, the defect lengths in the foveal external limiting membrane (ELM) and ellipsoid lines in these eyes were longer, and final VA was significantly poorer, compared with eyes without subfoveal hemorrhage. In comparisons between the final measurements in eyes with subfoveal hemorrhage in the IVR(-) and IVR(+) groups, while there were no differences in initial ocular conditions, final VA was significantly better in the IVR(+) group. The defects in the ELM and ellipsoid lines in the IVR(+) group were shorter than those of the IVR(-) group (p = 0.002 in both). Final VA was correlated with the defect lengths of foveal ELM and ellipsoid lines in both the IVR(-) and IVR(+) groups (both p < 0.001). In addition, the defect lengths of foveal ELM and ellipsoid lines were closely correlated with the duration of subfoveal hemorrhage (both p < 0.001). BRVO-associated subfoveal hemorrhage caused damage to the foveal photoreceptors, and visual dysfunction. However, IVR improved these prognoses, by accelerating the absorption of the subfoveal hemorrhage.

Cone photoreceptor neuroprotection conferred by CNTF in a novel in vivo model of battlefield retinal laser injury.

PURPOSE: To develop a reproducible laboratory model to simulate a battlefield foveal laser injury and to test potential neuroprotective effects of a single injection treatment that might be administered in a military setting. METHODS: Frequency-doubled 532-nm Nd:YAG laser was used to induce a threshold retinal injury bilaterally in transgenic reporter mice that have fluorescent cones. Intravitreal injection of ciliary neurotrophic factor (CNTF) was then administered to the lasered eye and compared with a contralateral sham injection of saline. The effect on fluorescent cone cell survival was quantified using a confocal scanning laser ophthalmoscope (cSLO), TUNEL assays, and quantitative real-time PCR (qPCR). RESULTS: At 3 weeks post-laser, cSLO imaging showed that the proportion of surviving cones expressing green fluorescent protein (GFP) was greater in CNTF-treated (54.1 ± 5.15% of baseline count) than in sham-injected eyes (28.7 ± 4.4%), which was accompanied by a reduction in TUNEL-positive cells. This difference in cone survival persisted at the 6-week point (treated, 39.6 ± 3.2% versus sham, 18.0 ± 3.8%). These changes were accompanied by a reduction in TUNEL-positive cells. The Bcl-2/Bax ratio was increased in CNTF-treated eyes at 1 week postlaser exposure relative to controls. CONCLUSIONS: A single intravitreal injection of CNTF protein was shown to improve cone survival when administered immediately after laser exposure. Similar treatments with CNTF might also have a role in attenuating retinal laser damage sustained by combat personnel in the military setting.

Traction-induced foveal damage predisposes eyes with pre-existing posterior vitreous detachment to idiopathic macular hole formation.

AIM: To propose a new mechanism for the development of idiopathic macular hole in the setting of pre-existing posterior vitreous detachment (PVD). METHODS: Patients were examined clinically with fundus contact lens biomicroscopy and high-definition optical coherence tomography (OCT) was used to characterize the structural changes in the fovea following PVD. RESULTS: Two patients presented with vitreofoveal separation and were found by high-definition OCT to have subtle foveal disruption and irregularity of the foveal contour with no evidence of a full thickness macular hole. Sequential examination of these patients demonstrated delayed formation of idiopathic macular hole. CONCLUSION: Traction-induced inner foveal damage occurring before or coincident with spontaneous vitreofoveal separation destabilizes the fovea and predisposes some eyes to delayed macular hole formation.

Bilateral macular hole secondary to remote lightning strike.

We report a case of a 16-year-old girl, who was struck by lightning, and experienced blurred vision in the right eye (RE) immediately following the episode. She reported for ophthalmic evaluation two months later. Examination revealed relative afferent pupillary defect in the RE. Posterior subcapsular cataract was noted in both eyes. Fundus examination revealed macular holes and multiple areas of RPE hyperpigmentation in the periphery in both eyes. Fundus fluorescein angiography showed increased choroidal transmission with early fluorescence and late fading in the foveal region and retinal pigment epithelium (RPE) stippling in the periphery in both eyes. This is the first case report of such nature in India to the best of our knowledge.

Temperature distribution during ICG-dye-enhanced laser photocoagulation of feeder vessels in treatment of AMD-related choroidal neovascularization.

Laser photocoagulation of the feeder vessels of age-related macula degeneration-related choroidal neovascularization (CNV) membranes is a compelling treatment modality, one important reason being that the treatment site is removed from the fovea in cases of sub- or juxtafoveal CNV. To enhance the energy absorption in a target feeder vessel, an indocyanine green dye bolus is injected intravenously, and the 805 nm wavelength diode laser beam is applied when the dye bolus transits the feeder vessel; this tends to reduce concomitant damage to adjacent tissue. A 3D theoretical simulation, using the Pennes bioheat equation, was performed to study the temperature distribution in the choroidal feeder vessel and its vicinity during laser photocoagulation. The results indicate that temperature elevation in the target feeder vessel increases by 20% in dye-enhanced photocoagulation, compared to just photocoagulation alone. The dye bolus not only increases the laser energy absorption in the feeder vessel but also shifts the epicenter of maximum temperature away from the sensitive sensory retina and retinal pigment epithelial layers and toward the feeder vessel. Two dominant factors in temperature elevation of the feeder vessel are location of the feeder vessel and blood flow velocity through it. Feeder vessel temperature elevation becomes smaller as distance between it and the choriocapillaris layer increases. The cooling effect of blood flow through the feeder vessel can reduce the temperature elevation by up to 21% of the maximum that could be produced. Calculations were also performed to examine the effect of the size of the laser spot. To achieve the same temperature elevation in the feeder vessel when the laser spot diameter is doubled, the laser power level has to be increased by only 60%. In addition, our results have suggested that more studies are needed to measure the constants in the Arrhenius integral for assessing thermal damage in various tissues.

[Optical coherence tomography follow-up of a case of solar maculopathy]. / Suivi d'un cas de maculopathie solaire par OCT.

Solar maculopathy is caused by sun-gazing without protection and in most cases appears to be reversible. Retinal damage may be caused by photochemical changes combined with a rise in temperature at the time of sun observation. We report a case of bilateral solar retinopathy following direct sun gazing after observation of the partial eclipse on 3 October 2005. A 25-year-old Caucasian man presented 24 h after watching the eclipse with symptoms of blurred vision and a bright positive central scotoma. Total direct viewing time was approximately 5 min. While observing the eclipse, the patient kept both eyes open. On presentation, his visual acuity was 20/25 in his right eye and 20/32 in his left eye. Ophthalmoscopic examination revealed a bilateral yellowish-white spot in the center of the foveal region. Static visual field examination did not disclose any absolute scotoma but a decrease in the foveal threshold was noted in both eyes. Optical coherence tomography (OCT) examination revealed a bilateral increased reflectivity of the inner foveal retina that was greater in the left eye. This finding was associated with a hyporeflective area of the underlying retinal pigment epithelium: choriocapillaris complex and an increase in retinal thickness. Eight days later, visual acuity was 20/20 in each eye. Funduscopy showed the yellow lesion had vanished. Four months after exposure, funduscopy was normal and OCT scan showed normal reflectivity of all retinal layers in the fovea. However, static visual field examination disclosed a decreased foveal threshold on the left eye. We compare the OCT findings in this patient with the data reported in the literature. Indeed, various OCT findings have been reported depending on the intensity and frequency of sun exposure. This observation demonstrates that OCT appears to be potentially useful in the evolutive follow-up of solar maculopathy, and emphasizes the importance of eye safety during solar eclipse observation.

Hipoplasia foveal aislada: presentación de un caso y revisión de la literatura / Hypoplasia isolated foveal: presentation of a case and review literature

Presentación de un caso de hipoplasia foveal como hallazgo ocular aislado. Presentación observacional de casos. Se diagnosticó hipoplasia foveal aislada a en un joven de 17 años con disminución de la visión desde la infancia, nistagmus, ausencia de reflejo foveolar, y capilares cruzando el meridiano horizontal, utilizando fotografía del fondo ocular y tomografía de coherencia óptica (OCT) en la fóvea central. El diagnóstico clínico se complementó con tomografía de coherencia óptica de alta resolución, la cual mostró extensión de todas las capas neurosensoriales de la retina en el área en la cual debería estar normalmente la fóvea. La tomografía de coherencia óptica puede complementar el diagnóstico clínico en la hipoplasia foveal.

Optic disc, foveal, and extrafoveal damage due to surgical separation of the vitreous.

OBJECTIVE: To evaluate the morphologic outcomes resulting from surgical vitreoretinal separation in young adult primates. MATERIALS AND METHODS: Vitrectomy and mechanical separation of the vitreous from the internal limiting lamina (ILL) of the posterior retina and surface of the optic disc were performed on 25 young adult cynomolgus monkey eyes in vivo. Lectin histochemical studies were used to evaluate the vitreoretinal interface. Morphologic outcomes were tabulated. RESULTS: In 11 of 25 eye regions, residual vitreous remained attached to the ILL in some of the regions. Localized ILL breaks or separation of the ILL from the neural retina was noted in 9 eyes. Retinal tissue loss, including avulsion of the ganglion cell, inner plexiform, or inner nuclear layers, was observed in 7 eyes. Avulsion of axon bundles in the optic disc was noted in 9 eyes. Significantly, partial- or full-thickness foveal tears were noted in 11 eyes. Based on the surgeons' intraoperative observations, small superficial optic disc or retinal hemorrhages were observed in 3 of 25 eyes. None of the eyes on which a vitrectomy alone was performed showed ILL damage, or retinal or optic disc tissue loss. CONCLUSION: Damage may occur to the optic disc, fovea, and extrafoveal retina as a result of surgical separation of the vitreous from the retina in young adult primates. CLINICAL RELEVANCE: These data support the contention that surgically induced damage at the level of the vitreoretinal interface may help explain the visual field defects noted after surgery to close full-thickness macular holes. These data also support the need for developing additional modalities to assist in vitreous separation, thereby reducing the risk of traumatic complications associated with purely mechanical procedures.

[Accidental laser burn]. / Impact laser accidentel.

A student suffered an accidental parafoveal laser burn during a physics experiment. We discuss here the clinical features and management and follow-up. This case presents a good example of photic injuries which can occur in many different settings.

[Eye injuries during a laser show]. / Augenverletzung während einer Lasershow.

BACKGROUND: Laser injuries are usually described in case reports concerning military personnel or scientists who had an accidental exposition to a laser. Today laser injuries to un-involved persons become more frequent. The potential danger for eye injuries was discussed by Birngruber and Gabel (2) in 1984. PATIENT: A patient presented 4 days after the accident with a monocular decline in vision and a scotoma after being hit by a ray of a discotheque laser. At the time of the accident the patient was standing on the dance floor watching a laser show. From that moment he reported a scotoma on the affected eye. The examination of the patient by an ophthalmologist 3 days later revealed a monocular decline in vision to 0.3 and a scotoma. Reading problems were reported. The fluorescence angiography confirmed the biomicroscopical barely visible line shaped defect next to the foveola which was according to our clinical experience caused by the ray of a laser. The vision defect and the scotoma remained stable during the follow up period. CONCLUSIONS: Before the first use of a show-laser unit it gets approved. Every change of the unit or the change of its position requires a new technical check by authorized institutions. At present many show lasers in use are not met with this requirement. Manipulations to the lasers are easy to perform and improve the intended show effect. The missing control practice provokes eye threatening situations for an enormous number of persons who are not aware of the danger.

Macular damage following lightning strikes.

Two men with recent history of lightining strike were referred to our hospital. Both patients complained of metamorphosia in one eye and reduced visual acuity. Funduscopy revealed target-like alterations at the fovea. Fluorescein angiography showed window defects of the central retinal pigment epithelium in both patients. One patient developed an anterior subcapsular cataract. If the eye is part of the current-circuit, the melanin granules of the iris, pigment epithelium, and choroid might act as a resistor. The resulting accumulation of heat may lead to damage of the surrounding tissues.

Accidental Nd:YAG laser injuries to the macula.

PURPOSE: To study the clinical course of accidental, single-focus Nd:YAG laser injuries to the macula. METHODS: We reviewed the clinical course of five eyes (four patients) that sustained macular injuries from a Nd:YAG laser. All patients were examined within 24 hours of injury and were observed without surgical intervention for a mean of 20 months (range, 12 to 32 months). RESULTS: A single full-thickness foveal or parafoveal retinal hole was apparent in all eyes either on initial examination or within two weeks of injury. All macular holes were within 650 microns of the foveal center. The mean final visual acuity was 20/60 (range, 20/25 to 20/400) and was related to the distance between the macular hole and the foveal center. None of the eyes developed either subretinal neovascularization or clinically significant epiretinal membrane formation during the study period. CONCLUSIONS: Despite initial poor visual acuity in patients who had a full-thickness foveal or parafoveal retinal hole, visual acuity improved without treatment when the site of the laser injury was located outside the foveal center.