Acuity In Right Eye Research Articles

Bilateral Optic Neuropathy Secondary to Fragrance Ingestion

1.1 Methanol ingestion by accident or in suicide attempts could produce life threatening conditions, but in survivors the more frequent is optic atrophy, a condition with poor results after correct treatment. 1.2 Case: A 46 years-old male come to emergency room secondary to decrease on visual acuity in right eye. He refers that 20 days ago underwent surgery for hip prosthesis fitting without complications and 48 hours after he presented the referred symptoms. He referred to be alcoholic for the past 18 years, with ingestion of fragrances the last 20 days. At physical exam visual acuity was light perception without color discrimination in right eye, and 20/800 in left eye. Intraocular pressure in both eyes were normal. Ocular movements were abnormal, without fixation and XT 30o. Anterior segment present a pupillary defect bilaterally, with mydriasis in right pupil, no reactive to light. In left eye moderate mydriasis and reactivity. Posterior pole of right eye presented an optic disc temporal pallor and optic disc periphery pallor in left eye. Visual fields show a paracentral scotoma in right eye, right superior temporal cuadrantanopsia, left eye with paracentral temporal scotoma (60o). After management with metilprednisolone for eight months’ visual acuity in right eye was finger count at 5 cm, left eye 20/400.

Chronic myelocytic leukemic fundus lesion: A case report.

The current study reports a case of a patient with a chronic myelocytic leukemic fundus lesion, initially diagnosed in the Department of Ophthalmology, Rizhao People's Hospital (Rizhao, China). A male, 23-years-of-age, presented with a dark shadow in the front of the right eye, accompanied with blurred vision for 3 days (visual acuity of right eye, 0.4; visual acuity of left eye, 0.6). In addition, the patient had experienced gingival bleeding for 2 years, and recurrent upper respiratory infections for 1 year. A fundus examination revealed mild binocular papillary edema, dilated and tortuous veins, and the retina exhibited large quantities of scattered and dark red bleeding spots. The bleeding spots had white spots in the center, which exhibited typical Roth spots, whilst routine blood examination, abdominal ultrasound, marrow biopsy and other laboratory tests confirmed the diagnosis of chronic myelogenous leukemia. Patients with leukemia typically present with initial symptoms that include fever, fatigue, anemia and hepatosplenomegaly, and a diagnosis as a result of eye-related symptoms is rare, rendering the present case unique.

Unilateral visual loss due to central retinal artery occlusion with total ophthalmoplegia following cervical spine surgery in prone position.

Blindness after spinal surgery is a rare complication, but it is serious, irreversible and incurable. Central retinal artery occlusion (CRAO) is rare after spinal surgery and ophthalmoplegia is even rarer. A 52-year-old male patient complained of loss of vision in right eye immediately after cervical spine surgery. On examination, the patient's visual acuity in right eye was absent perception of light. Right eye pupil was dialated and relative afferent pupillary defect (RAPD) was present. Extraocular movements were absent in all gazes in right eye. Intra-ocular pressure (IOP) was 26 mmHg in right eye and 16 mmHg in the left. Posterior segment examination revealed blurred disc margin with ischemic whitening of retina, thin and attenuated retinal arterioles and a central cherry red spot in right eye. Left eye was essentially normal. The causal factors of blindness in the patient were likely ischemia of the retina after venous congestion or temporary arterial occlusion resulting from changes in pressure to the tissues of the orbit. Factors including prolonged prone positioning with head end dependent position and possibility of orbital compression by the headrest could have contributed to impaired venous drainage, increase in IOP and reduction in perfusion pressure. Loss of vision post spinal surgery is a rarest of complication yet grave and irreversible. Because the problem involves mainly prone positioning of the patient, an appropriate position should be found so that facial and ocular compression can be avoided.

Squamous Papilloma over Lid Margin: An Uncommon Presentation

ABSTRACT Papilloma is a histopathological term describing tumors of a classical finger-like or cauliflower morphology. Though benign, they carry profound malignancy potential and can present at numerous anatomical locations, such as skin, cervix, esophagus, respiratory tract, breast duct, etc. Papillomas over conjunctiva are not frequently encountered and carry special significance. A 60-year-old diabetic female presented with a left upper lid marginal sessile mass of 9 months duration with mild epiphora and foreign body sensation. On examination, a solitary, fleshy, sessile, polypoidal mass measuring 1 × 1 cm was seen, with irregular cauliflower-like surface present over lateral aspect of left upper lid, firm in consistency with raised edges. Visual acuity in right eye was 6/18→6/9 and left eye 6/36→6/9, intraocular pressure (IOP) was 14.6 mm Hg in both eyes by Schiotz tonometry. Complete excision of the lesion employing microsurgical technique with close apposition of lid margin using 6-0 Vicryl sutures was done under local anesthesia (LA). Histopathological examination revealed stratified squamous epithelium forming papillae with variable goblet cells supported by prominent branching fibrovascular cores in the center. A satisfactory cosmetic result was achieved. Follow-up of 6 months did not reveal any recurrence. A satisfactory functional and cosmetic result achieved. Squamous papillomas over lid margin are uncommon presentations. Even though benign they carry morbidity potential in the form of chronic epiphora, corneal erosions, and lid deformities if inadequately managed. How to cite this article Goyal E, Gupta P, Dokania A, Rizvi Y. Squamous Papilloma over Lid Margin: An Uncommon Presentation. Int J Adv Integ Med Sci 2016;1(3):128-130.

急性特发性生理盲点扩大综合征一例

69岁男性患者，左眼突然视物发雾、变暗、阅读困难，伴闪光感6天，加重1天，否认糖尿病、高血压病。右眼视力HM，视乳头色白，血管变细。左眼视力0.04，最佳矫正视力0.25。眼底近视改变，RAPD(+)，色觉异常，ERG，mfERG异常，OCT示双眼视网膜外界膜、IS/OS层缺失。视野检查示左眼生理盲点明显扩大。FFA未见明显异常。治疗4月后，左眼视力0.2，最佳矫正视力0.5。各种症状好转，可以正常阅读工作。RAPD(−)，色觉仍异常。诊断：急性特发性生理盲点扩大综合征(AIBSE)。AIBSE是一种较少见的外层视网膜病变。 A 69-year-old male patient complained of a sudden visual loss and reading difficulties, combined with photopsia for 6 days, worse 1 day. Diabetes or hypertension was negative. The visual acuity of right eye was hand motion. The papillary of right eye was pale and the vessels of fundus were attenuated. The visual acuity of left eye was 0.04, and the best corrected visual acuity was 0.25. The myopic fundus was seen, RAPD (+), color anomaly, ERG and mfERG abnormalities were found. The OCT revealed the abnormalities of the IS/OS line and external limiting membrane in both eyes. Visual field detected blind spot extension in left eye. FFA showed minimal abnormalities. 4 months later, the visual acuity of left eye was improved to 0.2, and the best corrected visual acuity was 0.5. Various symptoms improved, and reading difficulties were gone. RAPD (−), color vision was still abnormal. The diagnosis of the patient is acute idiopathic blind spot enlargement syndrome (AIBSE). AIBSE is a rare outer retinopathy.

A case of vasculitis, retinitis and macular neurosensory detachment presenting post typhoid fever.

BackgroundOcular and extraocular immune-mediated phenomena are known to occur following febrile illness. Vasculitis, retinitis and neurosensory detachment are not well-recognized sequelae of typhoid fever.FindingsWe report a case of vasculitis, retinitis and macular neurosensory detachment presenting post typhoid fever. A 27-year-old female presented with decreased vision in right eye with history of typhoid fever (treated adequately 6 weeks prior). Her best corrected visual acuity in right eye was 20/125, N36. Fundus showed a patch of vasculitis and retinitis superior to the disc associated with macular neurosensory detachment and disc pallor. With oral steroids, the inflammation resolved and visual acuity improved to 20/20 at 6 weeks.ConclusionsImmune-mediated vasculitis and retinitis following typhoid fever may respond well to systemic steroids.

Familial presentation-best vitelliform disease

A 13-year-old boy presented to our ophthalmology outpatient department with gradual loss of vision in both eyes for past 6 months and the best-corrected visual acuity in right eye was 6/12 and left eye was 6/18. Anterior segment examination was within normal limits. Fundus examination showed right eye partially absorbed egg yolk like lesions in macula and left eye macula shows yellowish scrambled egg like lesions. Electro-oculogram showed reduced Arden's ratio. Patient was diagnosed to have best disease and as best disease is a bilateral macular dystrophy with autosomal-dominant inheritance it can occur in family members and therefore his parents and siblings were called for ocular examination and were found to have the best disease. So genetic counselling and screening of family members should be carried out or the disease can be missed out.

Driving Characteristics of Teens With Attention Deficit Hyperactivity and Autism Spectrum Disorder

Vehicle crashes are a leading cause of death among teens. Teens with attention deficit hyperactivity disorder (ADHD), autism spectrum disorder (ASD), or both (ADHD-ASD) may have a greater crash risk. We examined the between-groups demographic, clinical, and predriving performance differences of 22 teens with ADHD-ASD (mean age = 15.05, standard deviation [SD] = 0.95) and 22 healthy control (HC) teens (mean age = 14.32, SD = 0.72). Compared with HC teens, the teens with ADHD-ASD performed more poorly on right-eye visual acuity, selective attention, visual-motor integration, cognition, and motor performance and made more errors on the driving simulator pertaining to visual scanning, speed regulation, lane maintenance, adjustment to stimuli, and total number of driving errors. Teens with ADHD-ASD, compared with HC teens, may have more predriving deficits and as such require the skills of a certified driving rehabilitation specialist to assess readiness to drive.

Pigmented paravenous retinochoroidal atrophy with macular involvement

Case reportA 65-year-old female, with poor visual acuity in right eye since childhood, was referred to our hospital. Funduscopic examination revealed bone-spicule pigmentation and choroidal and retinal pigment epithelium atrophy along the vascular arcades, with macular involvement in right eye. The patient was diagnosed with pigmented paravenous retinochoroidal atrophy (PPRCA). DiscussionPPRCA is a rare disease, of unknown origin, characterised by retinochoroidal atrophy and retinal pigmentation along retinal veins, generally without macular involvement. Latest publications show a slow progression. No effective treatment is available.

Choroidal neovascularization in a case of angioid streaks

Presentation A 21 year old male patient reported in 2003 with complaint of diminution of vision in left eye since 1 month. Best corrected visual acuity OD was 20/20 and 20/120 OS. Fundus evaluation revealed angioid streaks in both eyes with scarred Choroidal neovascularization (CNV) in left eye [Fig. 1]. He was followed up regularly at intervals of 3 months. In 2010, he noticed blurring of vision in the right eye. BCVA was 20/30 OD. Fundus examination revealed presence of CNV which was confirmed on OCT [Fig. 2]. He was administered 3 intravitreal injections (IVT) of ranibizumab at intervals of 1 month each following which the lesion resolved and the visual acuity in right eye improved to 20/20 [Fig. 3]. One year later, the patient again experienced metamorphopsia with drop of BCVA to 20/30 OD. On examination the lesion appeared same as the previous follow-up and the OCT also did not suggest any fresh activity. However the fluorescein angiography revealed leakage nasal to the fovea suggestive of a recurrence from the CNV [Fig. 4]. This was treated successfully with 2 injections of ranibizumab, with the patient maintaining 20/20 OD for a period of 1 year on the last follow-up [Fig. 5].Figure 1: Fundus photograph and angiography (a, b, c) showing BE angioid streaks with a typical peripapillary ring and radiating pattern; hyperfluorescence nasal to the fovea OD (d, f) suggestive of previously regressed membrane; scarred lesion OS (b, e, g)Figure 2: Photographs (a, b) showing mild increase in retinal thickness nasal to the fovea with subsensory fluidFigure 3: Resolution of subsensory fluid and scarring (a, b) following 3 intravitreal injections of RanibizumabFigure 4: Fundus photograph OD (a), fluorescein angiography showing leakage nasal to the fovea (b) with OCT showing presence of a previously treated membrane without any surrounding fluid (c)Figure 5: Resolution of leak on the fluorescein angiography following 2 injections of anti-VEGF therapy (b, c)Discussion Angioid streaks are the result of crack like dehiscences in thickened, calcified and abnormally brittle collagenous and elastic portions of Bruchs membrane.[1] CNV is by far the most common cause of visual loss which can be monitored by fluorescein angiography and OCT. Laser photocoagulation has been shown to halt the progression of extrafoveal CNVs,[2] but for subfoveal and juxtafoveal lesions multiple IVT injections of anti-VEGF drugs are the mainstay of treatment.[3] However, a subset of these patients are known to have recurrences, hence they should be advised to undergo self-assessment using an Amsler grid to detect recurrences.

A case of von Hippel–Lindau disease with juxtapapillary retinal capillary hemangioma and nutcracker phenomenon

The aim of this study was to evaluate a patient with von Hippel-Lindau (VHL) syndrome and to discuss the clinical manifestations. A 25-year-old woman presented to our clinic with blurred vision for 2 months. Best corrected visual acuity in right eye was 20/50, and fundoscopic examination revealed juxtapapillary endophytic retinal capillary hemangioma. Examination findings on left eye were normal. On optical coherence tomography, exudation was prominent on macula. History revealed cerebellar operation because of cerebellar hemangioblastoma. On abdominal ultrasonography, liver hemangiomas and pancreatic cysts were seen, confirmed by abdominal computerized tomography (CT). Abdominal CT imaging also revealed nutcracker phenomenon. Transthoracic echocardiography showed atrial septal aneurysm without shunt. The patient refused ocular treatment. At 3-month control, ophthalmic findings were the same. To our knowledge, this is the first case of VHL disease reported to be associated with nutcracker phenomenon and atrial septal aneurysm. Systemic evaluation and regular follow-up should be recommended to subjects with VHL disease.

Atrofia coriorretiniana pigmentada paravenosa con afectación macular

Case reportA 65-year-old female, with poor visual acuity in right eye since childhood, was referred to our hospital. Funduscopic examination revealed bone-spicule pigmentation and choroidal and retinal pigment epithelium atrophy along the vascular arcades, with macular involvement in right eye. The patient was diagnosed with pigmented paravenous retinochoroidal atrophy (PPRCA). DiscussionPPRCA is a rare disease, of unknown origin, characterised by retinochoroidal atrophy and retinal pigmentation along retinal veins, generally without macular involvement. Latest publications show a slow progression. No effective treatment is available.

Optic perineuritis secondary to tuberculosis: A rare case presentation

A 58-year-old Malay lady, presented with gradual loss of vision in the right eye for 1 month duration. It was associated with right sided headache, nausea and vomiting. Patient had a history of contact with tuberculosis patient. On examination, visual acuity in right eye was no perception of light with presence of relative afferent pupillary defect. The left eye visual acuity was 6.0/7.5. There was a total restriction of extraocular movement in all direction (frozen eye) in the right eye. Both anterior segments were unremarkable. Fundoscopy in both eyes showed normal appearance of optic disc and retinal vessels. Other cranial nerves were normal. Lungs were clear and had no lymphadenopathy. Chest radiograph was normal. Erythrocyte sedimentation rate was elevated by 35 mm/h and Mantoux test was positive (20 mm). MRI of brain and orbit demonstrated thickening and irregularity of the right optic nerve on axial view with doughnut sign on coronal view. Patient was diagnosed to have optic perineuritis secondary to tuberculosis. She was treated with anti-TB drugs. Systemic corticosteroid was commenced after 2 weeks. The visual acuity was improved to hand motion after 1 month with almost complete resolution of extraocular movement.

Giant Epidermal Cyst of the Periorbital Area

Epidermal cysts of periorbit and intraorbit are common problems to ophthalmologists, but giant periorbital epidermal cyst is exceedingly rare. Only a few cases have been reported previously. A 62-year-old woman presented with a large right periorbital area mass that resulted in right upper lid complete ptosis and severe gaze limitation in all directions. Visual acuity of right eye was finger count (20/2000). Computed tomography and magnetic resonance imaging revealed a bone-destroying mass involving the lateral side of the right superior orbital limb. Complete surgical removal was performed through skin incision. The superior-lateral orbital limb was reconstructed with bone cement and Leibinger plate. Pathologic examination revealed a giant epidermal cyst (9.8×5.2×4.0 cm) of the periorbital area. After surgery, there was near-complete resolution of ptosis and gaze limitation. In addition, marked elevation of visual acuity was observed (20/125 on best-corrected visual acuity).

Bilateral internuclear opthalmoplegia in a patient with Devic’s neuromyelitis optica

Abstract Purpose To present a clinic case of Devic’s neuromyelitis optica (NMO) with bilateral ophtalmoplejia internuclear (OIN) , which is an extremely extraordinary association. To explain the reason why an episode of ophtalmoplejia internuclear appears in the context of a NMO case. To expose the visual involvement in NMO. Methods We studied and observed the clinical evolution of a patient diagnosed of NMO. The profile started with headache and sudden loss of visual acuity in right eye (RE), counting fingers at 1metre. She related neurologic symptoms as paresthesias 18 months ago. At the evaluation with visual field, eye fundus, Ishihara test was diagnosed of retrobulbar neuritis RE. We treated the patient with metilprednisolone and immunosuppressant drugs. She got better. After the childbirth, new neurologic symptoms that remined to transverse myelitis appeared. After a new treatment with metilprednisolone and plasmapheresis, she got better but a sudden bilateral OIN appeared Results The patient had a limitation in the movement of the eyes in addution and a bilateral nistagmus in abdution. The patient didn´t have a good reponse to the treatments. At present, she continues being admitted to hospital with paresis of legs and right arm. Double vision and OIN disappeared gradually. However, the patient has a residual exoforia in RE with nistagmus in abdution in left eye. Conclusion The MNO prevalence is lower than a case for million inhabitants, and it is not used to affect the encephalon trunk. To diagnose NMO are required two major criteria and at least two of the three minor ones, and this patient fullfills the diagnosis criteria.

518 Choriorétinopathie séreuse centrale récidivante chez deux patients sous inhibiteurs de phosphodiestérase pour dysfonctionnement érectile

Central serous chorioretinopathy typically affects young and middle aged men with type-A personality under stressful events. It has been occasionally related with exposure to increased levels of endogenous or exogenous glucocorticoids, but other associations are possible. We present two cases of recurrent central serous chorioretinopathy in two men taking phosphodiesterase inhibitors. In both cases, chorioretinopathy appeared after intake of the inhibitor, resolved once the latter discontinued, and re-appeared when the inhibitor was restarted. First case: A 56-year-old white male presented for blurred vision and micropsia in left eye. He had been using vardenafil over the last 6 weeks. Visual acuity of left eye was 20/25. Left fundus examination revealed a bullous central serous chorioretinopathy. Three months after vardenafil cessation, fundus alterations completely resolved and visual acuity returned to 20/20. Fifteen months later, after restarting vardenafil, he consulted with a 2-month history of progressive left eye vision reduction, and micropsia. Visual acuity was 20/32. Left fundus examination showed a new central serous macular detachment, confirmed by OCT. Once vardenafil re-stopped, chorioretinopathy regressed within 3 months. Second case: A 67- year-old white male presented for blurred vision in right eye progressively deteriorating over a 1-month period. He was taking tadalafil for the last 2 months. Visual acuity of right eye was 20/32 and right fundus examination and fluorescein angiography evidenced a central serous chorioretinopathy. Four months after stopping tadalafil, complete resolution of chorioretinopathy with normal fundus and OCT image and 20/20 visual acuity was observed. Six months later, the patient restarted tadalafil and chorioretinopathy recurred in his right eye within one month, with visual acuity returning to 20/32. Subsequent controls after stopping tadalafil showed improvement in OCT and visual acuity. Central serous chorioretinopathy was previously described in a patient taking sildenafil citrate, but no association was known with either vardenafil or tadalafil. The presented two cases of central serous chorioretinopathy after intake of vardenafil or tadalafil suggest that this condition should be added to the side effects of phosphodiesterase inhibitors.

Diabetic papillopathy diagnosed on retinal screening in an asymptomatic patient

Case study A 50-year-old Asian lady was diagnosed with type 2 diabetes mellitus in 1995. Compliance with diet and medications was poor. On maximal oral hypoglycaemic therapy (metformin, glibenclamide and rosiglitazone), the HbA1C was 9.1%. She refused insulin treatment on many occasions. She also had hypertension, microalbuminuria and hypercholesterolaemia. Retinal photographs (figure 1) taken in 2004 (visual acuity of right eye 6/6, left eye 6/6) showed background diabetic retinopathy. Repeat retinal pictures in 2006 are shown in figure 2 and left optic disc swelling noted. She denied any headache and visual acuity was 6/9 in both eyes. In view of the left disc oedema, she was referred to the ophthalmology department. Her visual acuity was 6/6 in each eye and her colour vision was normal. There was no uveitis or relative afferent pupillary defect. Formal visual fields were done (figure 3) which showed an enlarged left blind spot and some central visual field loss below the horizontal meridian in the left eye. The right visual field was normal. Her blood pressure was well controlled (130/80 mmHg) on medication. Blood tests which included full blood count, ESR, autoantibody screen, serum ACE, syphilis screen, B12 and Folate were all normal. Fluorescein angiography (figure 4) revealed dilated vessels over the optic disc with generalised leakage of dye at the optic disc, consistent with diabetic papillopathy.

Dengue maculopathy: A case report

Dengue fever is endemic in many countries of South East Asia. In spite of the occasional epidemics, dengue maculopathy remains a rare entity. A 31-year-old gentleman was admitted with a 6-day history of fever, generalised rash, headache and myalgia after a trip to Malaysia. There were no bleeding manifestations. The lowest platelet count was 71 x 10,000/ml, the haematocrit was 42.7%, and dengue serology was positive. On the 8th day of illness, he complained of bilateral blurred vision. Detailed visual examination showed visual acuity of right eye 6/30 and left eye 6/50. Fundoscopy revealed dilated veins, hyperaemic optic discs, flame and blot haemorrhages, soft exudates and macular ischaemia. After a course of high-dose steroids, the visual acuity as well as colour vision improved markedly. The pathology of maculopathy is not obvious in this case, but an immunological reaction is suspected. There is a risk of residual visual impairment, and there is no definitive treatment. The use of high-dose steroids seemed to improve visual acuity and colour vision. However, it is not known whether immunosuppression improves the prognosis. Time for resolution is from 8 weeks to 4 months. Since there is an increase in the incidence of dengue fever in our region, coupled with rising international travel, one could postulate that global incidence of dengue-related maculopathy may become significant. Ocular complications associated with dengue fever are rare but may result in permanent visual impairment. Dengue fever should be suspected in travellers, particularly those returning from endemic areas, and they should be systematically screened for maculopathy when visual disturbances arise.

2型糖尿病患者に併発したB群連鎖球菌性内因性眼内炎の1例

Endogenous endophthalmitis (EBE) is intraocular infection usually associated by bcteremia. Although, EBE is an uncommon disease, visually prognosis is very poor. Immune suppressive disease, such as diabetes or malignancy is a predisposing factor of EBE. Although, in east Asia, including Japan, gram negative organisms reported as common pathogen causing EBE, we here repot a case of group B streptococcus EBE. A 53- year old man, who has history of diabetes mellitus, was admitted to our hospital with compliant of sudden visual loss and pain at his right eye. His visual acuity was no hand perception in the right. In auscultation, there were coarse crackles at his left lung. Axial magnetic resonance imaging of eye showed exophthalmos of right eye and cellulites. Chest radiography revealed infiltration at the left middle lung field. EBE and pneumonia due to GBS were diagnosed and he was treated with intravenous cefotaxim. Despite of administration of antibiotics and vitreous surgery, deterioration of his visual activity was observed. Therefore antibiotics were changed to intravenous vancomicin and topical levofloxacin and amykacin were added also. But he finally lost his visual acuity of right eye.

Abnormal electroretinogram and abnormal electrooculogram after lightning-induced ocular injury

PURPOSE: To report a case of abnormal electrooculogram and abnormal electroretinogram after lightning-induced ocular injury. DESIGN: Interventional case report. METHODS: A 39-year-old man was struck on the left forehead by a bolt of lightning. After resuscitation, he regained consciousness. RESULTS: Ophthalmic examination disclosed a best-corrected visual acuity of right eye (RE): 20/25 and left eye (LE): 20/50, burned eyelashes, punctate keratitis, iridocyclitis, anterior subcapsular lens opacity, missing foveolar reflex, and macular pigment epithelial defect LE. Fluorescein angiography revealed only an area of punctate leaking in the left eye. Electrooculogram showed reduced amplitudes, in the left eye. Arden ratio was RE: 2.04 and LE: 1.52. The amplitudes of scotopic and photopic electroretinogram b-waves were reduced in the left eye. After uneventful cataract surgery in the left eye, the follow-up electrooculogram and electroretinogram still showed reduced amplitude in the left eye. CONCLUSION: Lightning is an uncommon cause of ocular injury. This is the first report of abnormal electro-oculogram and abnormal electroretinogram after lightning-induced ocular injury.