Case of persistent corneal epithelial damage after cataract surgery leading to diagnosis of vitamin A deficiency.

PURPOSE: To report our findings of reduced full-field electroretinograms (ff-ERGs) and abnormal optical coherence tomographic (OCT) images in a patient with poor visual acuity after cataract surgery who was eventually diagnosed with vitamin A deficiency (VAD). METHODS: This was a clinical study of a patient who complained of blurred vision after cataract surgery. To determine the cause of the reduced vision, we recorded full-field electroretinograms (ff-ERGs) to determine the scotopic and photopic status of the retina. We also performed optical coherence tomography to assess the changes in the retinal structure. Serological tests were performed. RESULTS: A 74-year-old man presented with persistent corneal epithelial damages and reduced vision that developed after conventional cataract surgery. OCT showed an interrupted ellipsoid zone, and fundus autofluorescence (FAF) showed a severe hypofluorescence in the retina of the left eye. The scotopic ff-ERGs were severely reduced, and the photopic ff-ERGs were mildly reduced. Serological examinations revealed a vitamin A concentration < 7 IU/dL (normal, 97-316 IU/dL). Based on these findings, we diagnosed the patient with VAD and started treatment with oral vitamin A supplements. After three months, his visual acuity, ff-ERGs, and OCT findings recovered to normal levels. The amplitudes and implicit times of the RETeval flicker ERGs increased to be within the normal range, and the hypofluorescence of the left eye disappeared. The length of the photoreceptor outer segments increased after the vitamin A supplementation. CONCLUSION: Our findings indicate that the ERGs are helpful for diagnosing patients with VAD associated with persistent corneal epithelial damages.

Electrophysiological effects of hyperbaric oxygen treatment on the healthy retina.

PURPOSE: The study aimed to investigate the electrophysiological effects of hyperbaric oxygen treatment (HBOT) on the retina after ten sessions in healthy eyes. METHODS: This prospective, interventional study evaluated forty eyes of twenty patients who were treated with HBOT of ten sessions with the diagnosis of an extraocular health problem. All patients underwent a complete ophthalmologic examination, including assessments of best-corrected visual acuity (BCVA), slit-lamp and pupil-dilated fundus examinations, full-field electroretinography (ffERG) measurements before and after HBOT within 24 h of the 10th session. The ffERG was recorded according to the International Society for Clinical Electrophysiology of Vision protocol using the RETI-port system. RESULTS: The mean age of patients was 40.5 years ranging from 20 to 59 years. Thirteen patients were administered HBOT for avascular necrosis, six patients for sudden hearing loss, and one patient for chronic osteomyelitis of the vertebra. BCVA acuity was 20/20 in all eyes. The mean spherical refractive was 0.56 dioptre (D), and the mean cylindrical refractive error was 0.75 D. Dark-adapted b-wave amplitude in 3.0 ERG was the only variable for the b-wave that showed a statistically significant decrease (p = 0.017). The amplitude of the a-waves in dark-adapted 10.0 ERG and light-adapted 3.0 ERG reduced significantly (p = 0.024, p = 0.025). The amplitude of N 1-P 1 in light-adapted 30 Hz Flicker ERG also demonstrated a statistically significant decrease (p = 0.011). Implicit times did not differ significantly in any of the ffERG data (p > 0.05). CONCLUSIONS: HBOT caused the deterioration of a-wave and b-wave amplitudes in ffERG after ten treatment sessions. The results showed that photoreceptors were adversely affected in the short term after HBOT treatment.

Bilateral compressive optic neuropathy and outer retinopathy due to optic canal hyperostosis in a child with isolated vitamin a deficiency.

PURPOSE: Vitamin A plays a crucial role in rod phototransduction, with deficient levels manifesting as night blindness. Animal models have demonstrated bone dysplasia in the setting of hypovitaminosis A. We present a rare case of bony overgrowth leading to bilateral compressive optic neuropathy, combined with outer retinopathy, in a paediatric patient secondary to isolated vitamin A deficiency. METHODS: A single case report was conducted from Toronto, Canada. RESULTS: A 12-year-old boy with known autism spectrum disorder presented with a 9-month history of progressive painless vision loss. Vision was 20/300 and hand motion in the right and left eye, respectively. Fundus photography demonstrated bilateral optic atrophy and yellow lesions notably in the right eye far periphery. Optical coherence tomography (OCT) imaging demonstrated thinning of the retinal nerve fibre layer, alterations in the ellipsoid zone, as well as retinal pigment epithelium deposits. Computed tomography imaging demonstrated sphenoid bone thickening with narrow optic canals and moderate optic atrophy bilaterally. Full-field electroretinogram (ERG) demonstrated mildly reduced dark adapted (DA) 0.01 b-wave amplitudes and electronegative configuration of DA 3.0 and DA 10.0 ERG; the light adapted ERGs were normal. The patient was treated with pulse vitamin A therapy. Subsequently, the DA ERG normalized, outer retinal changes reversed and vision stabilised; no surgical intervention was conducted. CONCLUSION: This case represents a rare presentation of compressive optic neuropathy with concomitant outer retinopathy secondary to isolated vitamin A deficiency. Despite improvement in outer retinal integrity on OCT imaging and ERG testing results following vitamin A supplementation, no functional improvement was obtained due to severe optic atrophy.

Vitamin A deficiency and the retinal "double carrot" sign with optical coherence tomography.

BACKGROUND: Spectral-domain optical coherence tomography (SD-OCT) and full-field electroretinography (ERG) allow retinal assessment with vitamin A deficiency (VAD). Using SD-OCT, this study aimed to characterize and follow a novel retinal abnormality in patients with VAD and intramuscular supplementation. METHODS: Patients with VAD were retrospectively reviewed, including SD-OCT and electroretinography. RESULTS: Three patients had VAD following bariatric or colon surgery and varying supplementation. All had nyctalopia, extinguished scotopic rod-specific function with ERG, and decreased serum vitamin A. None demonstrated surface abnormalities. All received intramuscular vitamin A with subjective resolution of symptoms. On SD-OCT, four of six eyes exhibited homogenous foveal hyperreflectivity anterior to retinal pigment epithelium-Bruch complex, reminiscent of a "double carrot", which improved following supplementation. ERG findings demonstrated improved scotopic rod-specific function in all cases; however, photopic function remained diminished in two cases. CONCLUSIONS: Structural improvement of the proposed "double carrot" sign occurs soon after vitamin A supplementation. While scotopic function improves rapidly following supplementation, cone function recovers more slowly. Therefore, foveal changes such as the "double carrot" sign suggest that structural recovery of cones precedes functional recovery.

Documentation of recovery from vitamin A deficiency-related retinopathy via multimodal imaging and electroretinogram testing.

PURPOSE: To describe vitamin A deficiency using multimodal functional visual assessments and imaging. METHODS/CASE: A 50-year-old female with past medical history significant for Roux-en-Y gastric bypass surgery complained of nyctalopia and "yellowing" of vision. RESULTS: Vitamin A levels were noted to be < 0.06 mg/L (normal 0.3-0.12 mg/L). Fundus examination was notable for peripheral yellow punctate lesions, superior arcuate defects on HVF 30-2 testing, an indistinct ellipsoid zone on SD-OCT, and absent rod responses and severely reduced amplitudes for the cone photoreceptors on full-field ERG. These findings resolved with initiation of parenteral vitamin A supplementation. CONCLUSION: This report documents an example of vitamin A deficiency in the developed world. We aim to provide a comprehensive description of clinical examination and multimodal imaging findings before and after vitamin supplementation for vitamin A deficiency.

Retinal Temperature Determination Based on Photopic Porcine Electroretinogram.

OBJECTIVE: Subthreshold retinal laser therapy (SLT) is a treatment modality where the temperature of the retinal pigment epithelium (RPE) is briefly elevated to trigger the therapeutic benefits of sublethal heat shock. However, the temperature elevation induced by a laser exposure varies between patients due to individual differences in RPE pigmentation and choroidal perfusion. This study describes an electroretinography (ERG)-based method for controlling the temperature elevation during SLT. METHODS: The temperature dependence of the photopic ERG response kinetics were investigated both ex vivo with isolated pig retinas and in vivo with anesthetized pigs by altering the temperature of the subject and recording ERG in different temperatures. A model was created for ERG-based temperature estimation and the feasibility of the model for controlling SLT was assessed through computational simulations. RESULTS: The kinetics of the photopic in vivo flash ERG signaling accelerated between 3.6 and 4.7%/°C, depending on the strength of the stimulus. The temperature dependence was 5.0%/°C in the entire investigated range of 33 to 44°C in ex vivo ERG. The simulations showed that the method is suitable for determining the steady-state temperature elevation in SLT treatments with a sufficiently long laser exposure and large spot size, e.g., during > 30 s laser exposures with > 3 mm stimulus spot diameter. CONCLUSIONS: The described ERG-based temperature estimation model could be used to control SLT treatments such as transpupillary thermotherapy. SIGNIFICANCE: The introduced ERG-based method for controlling SLT could improve the repeatability, safety, and efficacy of the treatment of various retinal disorders.

Neuroprotective Effects and Therapeutic Potential of Transcorneal Electrical Stimulation for Depression.

Transcorneal electrical stimulation (TES) has emerged as a non-invasive neuromodulation approach that exerts neuroprotection via diverse mechanisms, including neurotrophic, neuroplastic, anti-inflammatory, anti-apoptotic, anti-glutamatergic, and vasodilation mechanisms. Although current studies of TES have mainly focused on its applications in ophthalmology, several lines of evidence point towards its putative use in treating depression. Apart from stimulating visual-related structures and promoting visual restoration, TES has also been shown to activate brain regions that are involved in mood alterations and can induce antidepressant-like behaviour in animals. The beneficial effects of TES in depression were further supported by its shared mechanisms with FDA-approved antidepressant treatments, including its neuroprotective properties against apoptosis and inflammation, and its ability to enhance the neurotrophic expression. This article critically reviews the current findings on the neuroprotective effects of TES and provides evidence to support our hypothesis that TES possesses antidepressant effects.

Systemic administration of the di-apocarotenoid norbixin (BIO201) is neuroprotective, preserves photoreceptor function and inhibits A2E and lipofuscin accumulation in animal models of age-related macular degeneration and Stargardt disease.

Atrophic A\age-related macular degeneration (AMD) and Stargardt disease (STGD) are major blinding diseases affecting millions of patients worldwide, but no treatment is available. In dry AMD and STGD oxidative stress and subretinal accumulation of N-retinylidene-N-retinylethanolamine (A2E), a toxic by-product of the visual cycle, causes retinal pigment epithelium (RPE) and photoreceptor degeneration leading to visual impairment. Acute and chronic retinal degeneration following blue light damage (BLD) in BALB/c mice and aging of Abca4-/- Rdh8-/- mice, respectively, reproduce features of AMD and STGD. Efficacy of systemic administrations of 9'-cis-norbixin (norbixin), a natural di-apocarotenoid, prepared from Bixa orellana seeds with anti-oxidative properties, was evaluated during BLD in BALB/c mice, and in Abca4-/- Rdh8-/- mice of different ages, following three experimental designs: "preventive", "early curative" and "late curative" supplementations. Norbixin injected intraperitoneally in BALB/c mice, maintained scotopic and photopic electroretinogram amplitude and was neuroprotective. Norbixin chronic oral administration for 6 months in Abca4-/- Rdh8-/- mice following the "early curative" supplementation showed optimal neuroprotection and maintenance of photoreceptor function and reduced ocular A2E accumulation. Thus, norbixin appears promising as a systemic drug candidate for both AMD and STGD treatment.

Acute phase treatment in central retinal artery occlusion: thrombolysis, hyperbaric oxygen therapy or both?

Central retinal artery occlusion (CRAO) is a neuro-ophthalmological emergency. There is a finite time window for acute interventions such as revascularization (e.g. intravenous thrombolysis-IVT) and retinal oxygenation (e.g. hyperbaric oxygen therapy-HBOT) therapies. Case 1: A 35-year-old female presented with CRAO in the right eye (OD) confirmed by fluorescein angiography (FA) and optical coherence tomography (OCT). She underwent 4 sessions of HBOT (100% O2 at 2.4 atmosphere absolute for 90 min). Afterwards, visual defect on the nasal field was kept but visual acuity (VA) improved from counting fingers to 1.0. Case 2: A 65-year-old male presented with CRAO in his left eye (OS) with 1.5 h of evolution. Orbital sonography and OCT confirmed the presence of an embolus and he underwent IVT with rTPA (0.9 mg/kg). VA improved from light perception to 0.1. Case 3: A 21-year-old male presented acute visual loss in his OD with 2.5 h of evolution. OCT and retinography identified CRAO. He was submitted to IVT (rTPA-0.9 mg/kg) followed by 12 sessions of HBOT. VA improved from hand motion to 1.0. Our case series depicts the approaches and possible outcomes in acute management of an infrequent, but highly morbid, cerebroretinovascular disorder. Future clinical trials are warranted to tackle current difficulties in CRAO treatment.

The Ocular Protective Effects of Nano/Submicron Particles Prepared from Lycium barbarum Fruits Against Oxidative Stress in an Animal Model.

Purpose: To investigate the antioxidative properties of Lycium barbarum (LB) fruits in the eyes and to study whether LB fruits prepared with new nanotechnology have stronger antioxidative effects. Methods: Fourteen days post-supplementation with milled or blended LB fruits, intravitreal paraquat (PQ) was injected into Wistar rats to create oxidative stress. After an additional 14-day supplementation with LB fruits, the rats were sacrificed. An electroretinogram (ERG) was performed to evaluate retinal function before and after the PQ injection. Expression levels of antioxidative responders' mRNA in retina were detected by reverse transcription-polymerase chain reaction. Superoxide dismutase (SOD) and glutathione reductase activity in the aqueous humor (AqH) were analyzed by ELISA. Immunohistochemistry was conducted to evaluate the morphological changes of retina and the levels of oxidative biomarkers. The levels of cell apoptosis were assessed by the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. The reactive oxygen species (ROS) levels in AqH were measured by chemiluminescence methods. Results: The murine eyes supplemented with LB fruits exhibited several changes compared with the control group. The ERGs revealed significant improvement in retinal function. The mRNA expression levels of oxidative responders were downregulated in the retinas. The ROS was significantly reduced in the retinas, but the SOD meaningfully increased in the AqH. Immunohistochemistry staining and TUNEL assays showed decreased incidences of oxidative biomarkers and apoptosis in the retinas. Milled LB fruits exhibited better antioxidative effects than blended fruits. Conclusions: Milled LB fruits demonstrated superior protection against oxidative threats than blended fruits. Thus, these fruits could be an inexpensive supplement for many oxidative stress-related ocular diseases.

LONG-TERM MULTIMODAL IMAGING OF OCULAR FINDINGS ASSOCIATED WITH THIAMINE-RESPONSIVE MEGALOBLASTIC ANEMIA.

PURPOSE: To report on 5-year multimodal imaging of ocular findings in a patient with thiamine-responsive megaloblastic anemia. METHODS: Observational case report. RESULTS: A 20-year-old-man with a history of thiamine-responsive megaloblastic anemia demonstrated a symmetric bull's eye maculopathy. Spectral domain optical coherence tomography revealed disruption of the parafoveal ellipsoid zone, fundus autofluorescence demonstrated foveal hypoautofluorescence, and full-field electroretinogram testing revealed a decreased photopic and scotopic response consistent with cone-rod dystrophy. His best-corrected visual acuity remained stable over 5 years at 20/50 in the right eye and 20/40 in the left eye, and visual field testing remained stable over time. CONCLUSION: Ocular manifestations in thiamine-responsive megaloblastic anemia are uncommon and variable. In this case, multimodal imaging and electroretinogram findings are consistent with cone-rod degeneration. The patient is taking daily thiamine supplementation, and visual acuity, funduscopic examination, spectral domain optical coherence tomography, and autofluorescence remained stable over a 5-year period.

Antioxidant effects of Lycium barbarum polysaccharides on photoreceptor degeneration in the light-exposed mouse retina.

We assessed the neuroprotective effects of Lycium barbarum Polysaccharides (LBP) on photoreceptor degeneration and the mechanisms involved in oxidative stress in light-exposed mouse retinas. Mice were given a gavage of LBP (150 mg/kg or 300 mg/kg) or phosphate buffered saline (PBS) for 7 days before exposure to light (5000 lx for 24 h). We found that LBP significantly improved the electroretinography (ERG) amplitudes of the a- and b-waves that had been attenuated by light exposure. In addition, changes caused by light exposure including photoreceptor cell loss, nuclear condensation, an increased number of mitochondria vacuoles, outer membrane disc swelling and cristae fractures were distinctly ameliorated by LBP. LBP treatment also significantly prevented the generation of reactive oxygen species (ROS) compared with PBS treatment. The levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and thioredoxin reductase (TrxR1) mRNA were decreased in PBS-treated mice compared with controls but increased remarkably in LBP-treated mice. The mRNA levels of the DNA repair gene Poly (ADP-ribose) polymerase (PARP14) was increased in PBS-treated mice but decreased significantly in the LBP-treated mice. Our findings indicate that pretreatment with LBP effectively protected photoreceptor cells against light-induced retinal damage probably through the up-regulation of the antioxidative genes Nrf2 and TrxR1, the elimination of oxygen free radicals, and the subsequent reduction in the mitochondrial reaction to oxidative stress and enhancement in antioxidant capacity. In addition, the decreased level of PARP14 mRNA in LBP-treated mice also indicated a protective effect of LBP on delaying photoreceptor in the light-damaged retina.

Electrophysiological assessment for early detection of retinal dysfunction in ß-thalassemia major patients.

PURPOSE: The purpose of this study was to assess the role of various diagnostic tests in early detection of retinal changes in ß-thalassemia major patients. METHODS: Thirty-eight visually asymptomatic ß-thalassemia major patients receiving regular blood transfusions and iron-chelation therapy with deferoxamine (group A, n = 13), deferasirox (group B, n = 11) or deferoxamine with deferiprone (group C, n = 14) and fourteen age- and sex- matched healthy individuals were included in the study. All participants underwent ophthalmoscopy, full-field electroretinography (ERG), visual evoked potentials (VEP), multifocal electroretinography (mfERG), fundus autofluorescence (FAF) imaging and optical coherence tomography (OCT) scans. RESULTS: Retinal pigment epithelium changes were present in two cases. Scotopic ERG demonstrated decreased a-wave amplitude in groups A, B and C (p = 0.03, p = 0.002 and p = 0.002, respectively) and decreased b-wave amplitude in groups B and C (p = 0.002 and p = 0.01, respectively) compared to controls. Photopic ERG showed delayed b-wave latency in groups A and C (p = 0.03 and p = 0.03, respectively) ERG maximal combined response and VEP response did not differ between groups. MfERG showed reduced retinal response density in ring 1 in groups A, B, C (p < 0.001, p < 0.001, p = 0.001, respectively) and ring 2 in group B (p = 0.02) and delayed latency in ring 5 in groups A and B (p = 0.04 and p = 0.04, respectively). Abnormal FAF images appeared in three cases and OCT abnormalities in one case, whereas no changes were observed in controls (p = 0.55 and p = 1.00, respectively). CONCLUSIONS: Full-field ERG and mfERG are more sensitive tools for detecting early retinal changes in ß-thalassemia patients compared with ophthalmoscopy, VEP, FAF imaging and OCT scans.

Teleretinography into diabetes integrated care: an Italian experience.

INTRODUCTION: Integrated care, by allowing information exchange among health professionals, improves outcomes and favours a reduction in hospital admission in diabetes. Retinal complications can be sight-threatening, and diabetic patients often miss the suggested yearly clinical examination. METHODS: Teleretinography can be easily performed in patients attending Diabetes Clinics: images are sent to a remote ophthalmologist, grading and instructions are received and forwarded to General Practitioners by a dedicated software. RESULTS: We here report the results of teleretinography performed in our Diabetes Clinic in 362 patients missing the yearly fundus examination: 253 patients showed no diabetic retinopathy, 86 a mild form, and 23 needed referral to hospital settings. CONCLUSIONS: Teleretinography is a user-friendly, time-saving and cost-effective technique, easily integrable into integrated care, allowing a better adherence to guidelines.

Vasculopatía coroidea polipoidea bilateral, coexistiendo con degeneración macular asociada a la edad exudativa y atrófica / Bilateral polypoidal choroidal vasculopathy coexisting with exudative and atrophic age-related macular degeneration

OBJETIVO: Presentar el caso clínico de un paciente que presenta vasculopatía coroidea polipoidea (VCP) bilateral y degeneración macular asociada a la edad (DMAE) exudativa y atrófica, su tratamiento. Caso clínico. Mujer de 83 años presenta disminución de agudeza visual en el ojo izquierdo (OI). Al examen presenta DMAE atrófica en el OD, y en el OI una lesión naranja yuxtapapilar con depósitos lipídicos y otra gris subfoveal inferior. En la angiografía fluoresceínica y de verde de indocianina (AVI) se evidencia una membrana neovascular clásica en el OI, y pólipos yuxtapapilares en ambos ojos. Se realiza terapia fotodinámica con inyecciones anti-VEGF con estabilización de lesiones. CONCLUSIÓN: La coexistencia de la vasculopatía polipoidea coroidea y la DMAE exudativa es posible. Ante la sospecha de VCP debe realizarse AVI

OBJECTIVE: To present the case of simultaneous presentation of polypoidal choroidal vasculopathy (PCV) and aged-related macular degeneration (AMD). Case report. An 83-year-old woman presented with decreased vision in the left eye (LE). In the examination there was an orange peripapillary lesion surrounded by lipid exudates and another subfoveal greyish lesion in the LE. Disciform scarring was observed in the right eye. Fluorescein angiography showed a classic neovascular membrane in in the LE fovea. Indocyanine angiography (ICGA) showed a polyp-like peri-papillary aneurysmal dilation in both eyes. The patient was treated with photodynamic therapy and anti-VEFG injections with stabilisation of the lesions. CONCLUSION: PCV and AMD can co-exist in unusual cases. When PCV is suspected, ICGA is mandatory for diagnosis

Migraine photophobia originating in cone-driven retinal pathways.

Migraine headache is uniquely exacerbated by light. Using psychophysical assessments in patients with normal eyesight we found that green light exacerbates migraine headache significantly less than white, blue, amber or red lights. To delineate mechanisms, we used electroretinography and visual evoked potential recording in patients, and multi-unit recording of dura- and light-sensitive thalamic neurons in rats to show that green activates cone-driven retinal pathways to a lesser extent than white, blue and red; that thalamic neurons are most responsive to blue and least responsive to green; and that cortical responses to green are significantly smaller than those generated by blue, amber and red lights. These findings suggest that patients' experience with colour and migraine photophobia could originate in cone-driven retinal pathways, fine-tuned in relay thalamic neurons outside the main visual pathway, and preserved by the cortex. Additionally, the findings provide substrate for the soothing effects of green light.

Oral Administration of Forskolin, Homotaurine, Carnosine, and Folic Acid in Patients with Primary Open Angle Glaucoma: Changes in Intraocular Pressure, Pattern Electroretinogram Amplitude, and Foveal Sensitivity.

PURPOSE: To evaluate the effects of a food supplement containing forskolin, homotaurine, carnosine, folic acid, vitamins B1, B2, B6, and magnesium in patients with primary open angle glaucoma (POAG) already in treatment and compensated by intraocular pressure (IOP)-lowering drugs, during a period of 12 months. METHODS: Twenty-two patients (44 eyes) with POAG, with their IOP compensated by topical drugs, were enrolled and randomly assigned to the food supplement or control treatment group. The additional food supplement treatment consisted of 2 tablets per day (1 in the morning, 1 in the evening) given for 1 year of a balanced association of homotaurine, Coleus forskohlii root extract, L-carnosine, folic acid, vitamins B1, B2, B6, and magnesium. Pattern Electroretinogram (PERG) amplitude, foveal sensitivity obtained with the visual field analyzer frequency doubling technology, and IOP were detected at enrollment (T0), 3 months (T1), 6 months (T2), 9 months (T3), and 12 months (T4). RESULTS: We observed in treated patients a significant further decrease of IOP and an improvement of PERG amplitude at 6, 9, and 12 months, and foveal sensitivity at 12 months. All values remained substantially stable in control patients. CONCLUSIONS: The results of the present pilot study indicate that the components of the food supplement reach the eye in a detectable manner, as evidenced by the effects on the IOP. Moreover, they suggest a short-term neuroactive effect, as indicated by the improvement of PERG amplitude and foveal sensitivity in treated, but not in control patients.

Progesterone treatment in two rat models of ocular ischemia.

PURPOSE: To determine whether the neurosteroid progesterone, shown to have protective effects in animal models of traumatic brain injury, stroke, and spinal cord injury, is also protective in ocular ischemia animal models. METHODS: Progesterone treatment was tested in two ocular ischemia models in rats: a rodent anterior ischemic optic neuropathy (rAION) model, which induces permanent monocular optic nerve stroke, and the middle cerebral artery occlusion (MCAO) model, which causes transient ischemia in both the retina and brain due to an intraluminal filament that blocks the ophthalmic and middle cerebral arteries. Visual function and retinal histology were assessed to determine whether progesterone attenuated retinal injury in these models. Additionally, behavioral testing and 2% 2,3,5-triphenyltetrazolium chloride (TTC) staining in brains were used to compare progesterone's neuroprotective effects in both retina and brain using the MCAO model. RESULTS: Progesterone treatment showed no effect on visual evoked potential (VEP) reduction and retinal ganglion cell loss in the permanent rAION model. In the transient MCAO model, progesterone treatment reduced (1) electroretinogram (ERG) deficits, (2) MCAO-induced upregulation of glutamine synthetase (GS) and glial fibrillary acidic protein (GFAP), and (3) retinal ganglion cell loss. As expected, progesterone treatment also had significant protective effects in behavioral tests and a reduction in infarct size in the brain. CONCLUSIONS: Progesterone treatment showed protective effects in the retina following MCAO but not rAION injury, which may result from mechanistic differences with injury type and the therapeutic action of progesterone.

[Clinical efficacy of Vitrum Memory in patients with glaucoma and dry form of age-related macular degeneration].

The study was conducted to assess clinical efficacy of Vitrum Memory in therapeutic dosage for 3 months in patients with glaucoma and dry form of age-related macular degeneration (AMD). Survey data, visual acuity, biomicroscopy, computer perimetry, electrophysiological studies (EPS): visual evoked potentials (VEP) and pattern electroretinogram (pattern ERG), HRT-3 and OCT were evaluated. Subjective improvement, reduction of visual and mental fatigue, increase of light sensitivity, as well as statistically significant improvement in visual functions (at both computer perimetry and EPS) were achieved.

Xerophthalmia and acquired night blindness in a patient with a history of gastrointestinal neoplasia and normal serum vitamin A levels.

A 69-year-old male patient presented to our department with a 3-month history of nyctalopia. Reviewing of his general health revealed a history of gastrointestinal tumor treated with a modified WHIPPLE operation. Ocular findings at presentation included mild xerophthalmic features and nonspecific pigmentary retinal changes. A standard full-field electroretinogram (ERG) was obtained that showed normal photopic function and extinguished scotopic function. The ocular symptoms, the history and the ERG findings suggested vitamin A deficiency as a possible cause for his complaints. Serum vitamin A levels were subsequently requested, but the results were within normal limits. Despite the normal serum vitamin A levels, the patient was instructed to commence treatment with high doses of oral vitamin A supplements. One month after the onset of the treatment, the patient reported that his visual function has significantly improved, while repeat ERG testing revealed that scotopic function has improved to normal levels. This case highlights that in patients with acquired night blindness due to vitamin A deficiency, the ERG responses possibly represent a more sensitive marker compared to the serum levels of vitamin A.