Retinal Opacification Research Articles

Optical Coherence Tomography Angiography Findings Associated With Accelerated Hypertension.

Introduction Accelerated hypertension, that is a systolic blood pressure greater than 180 mmHg and a diastolic blood pressure greater than 120 mmHg is often accompanied by fundoscopic signs with the potential of systemic and visual morbidity.We report on the clinical and optical coherence tomography angiography (OCTA) findings in a cohort of hypertensive patients with accelerated hypertension. Methods Patients, presenting to the emergency room/intensive care unit, who met the clinical definition of accelerated hypertension (a blood pressure >180/120 mmHg,), were triaged to the intensive care unit. Following blood pressure reduction via pharmacological methods, a standard panel of hematological tests, cardiac evaluation tests, and the necessary systemic imaging was performed. They underwent a bedside dilated fundus examination with subsequent fundus photography/OCTA using a Topcon DRI OCT plus (Topcon Corporation, Tokyo, Japan). The records of these patients were evaluated. Results We analyzed the records of 16 patients (12 males (75%), and four females (25%)) with ages ranging from 16 to 75 years (mean 47.6 years). Eleven patients consented to a detailed evaluation. These included nine males (81.8%) and two females (18.1%) with ages ranging from 16 to 63 years (mean 46.3 years).Comorbidities included pre-existing hypertension (nine patients, 81.8%), chronic kidney disease (three patients, 27.2%), and diabetes mellitus type 2 (two patients, 18.1%). Clinical findings in these 22 eyes included arteriolar changes consistent with Keith Wagener Barker (KWB) grade 1 (two eyes, 9.0%), grade 2 (10 eyes, 45.4%), grade 3 (eight eyes, 36.3%), and grade 4 (two eyes, 9.0%). OCTA findings included capillary nonperfusion in the superficial capillary plexus in the areas of retinal opacification (seven eyes, 31.8%). Conclusion OCTA studies of the macular, as well as the entire posterior pole vasculature, may help to detect retinal microangiopathy, permit accurate grading,and subsequently develop a model that permits the quantification of systemic and ocular risk in these patients.

Management of Icteric Vitreous, Retinal Opacification, and Atypical Retinopathy of Prematurity.

A dichorionic, diamniotic twin born at 24-0/7 weeks and 740 g developed hyperbilirubinemia, necrotizing enterocolitis, and sepsis. Photographic imaging documented vitreous opacification, which was absent in the fellow twin. Retinal opacification was presumed secondary to embolic sepsis and responded to systemic antibiotics. Subsequent dropout of vascularized retina corresponded to areas of retinal opacification. Type 1 retinopathy of prematurity (ROP)-Zone I, Stage 3 ROP bilateral-demonstrated a rapid and durable response to off-label intravitreal bevacizumab 0.625 mg. Retinal opacification resolved between 39 and 40 weeks postmenstrual age. Systemic comorbidities may alter the appearance, course, and management of ROP. [Ophthalmic Surg Lasers Imaging Retina 2024;55:164-167.].

Retinal OCT findings in acute central retinal artery occlusion of varying severity at different disease stages – a retrospective, observational study

PurposeTo study the optical coherence tomography (OCT) changes in eyes with acute central retinal artery occlusion (CRAO) of different severity and at different disease stages.MethodsThe study included acute CRAO cases of < 7 days duration, imaged on OCT at various time points. Based on the OCT findings at presentation, cases were classified into three severity groups: mild, moderate, and severe. OCT scans were evaluated and classified into four-time intervals based on symptom duration.ResultsThere were 39 eyes from 38 patients with acute CRAO who underwent 96 OCT scans. At presentation, the study had 11, 16, and 12 cases of mild, moderate, and severe CRAO, respectively. Middle retinal layer opacification was more common in mild CRAO cases, which caused inner retinal layer thinning over time. Moderate CRAO cases had total inner retinal layer opacification, which resulted in retinal thinning over time. Prominent middle limiting membrane (p-MLM) sign was seen in mild and moderate CRAO eyes while were not visualised in severe CRAO. This sign gradually faded out over time. Other OCT findings in higher grades of CRAO included inner retinal fluid, neurosensory detachment, internal limiting membrane detachment, hyperreflective foci, and posterior vitreous opacities. Regardless of the CRAO grade, the final end-point seen was inner retinal layer thinning over time.ConclusionOCT in CRAO is a useful for determining the severity of retinal ischemia, disease stage, tissue damage mechanism, and final visual outcome. More prospective studies analysing a larger number of cases at fixed time points will be required in the future.Trial RegistrationTrial Registration Number: Not applicable.

CMV Retinitis with Panretinal Occlusive Vasculitis

ABSTRACT Purpose To report the clinical features of cytomegalovirus (CMV) retinitis with panretinal occlusive vasculitis. Methods Retrospective case series. Results Four eyes in 3 non-HIV patients (male: female = 3:0) were included. Previous medical history included diabetes mellitus (n = 2), age-related macular degeneration (n = 1), and Multiple myeloma under chemotherapy (n = 1). All patients were treated with oral valganciclovir and intravitreal ganciclovir. Slow resolution of retinitis related retinal opacification was noted in all 4 eyes. Two eyes had anti-viral agents discontinued despite the persistent retinitis related opacification and the lesions slowly resolved in the following months. The final decimal visual acuity was equal to or worse than 0.02 in 3 of the 4 eyes. Conclusion In eyes of CMV retinitis with panretinal occlusive vasculitis, rapid resolution of retinitis lesions is an unreliable sign evaluating the therapeutic efficacy of anti-viral agents. Besides, despite treatment of anti-viral agents, deteriorating vascular occlusion may further endanger macular function.

Successful management of an unusual extra-ocular foreign body.

A 25 yr old male†, industrial worker by profession, presented to the emergency setting of Government Medical College, Chandigarh, in July 2020, with a rare foreign body impaction. This was after he sustained occupational ocular trauma while cutting iron sheets with a manual work tool machine. He was not wearing any ocular protective gear. Ocular examination revealed impaction of multiple round brass foreign bodies in the right lower lid (Fig. 1A) and closed globe injury to the globe with vitreous haemorrhage and peri-papillary retinal pallor (Fig. 1B). Non-contrast computed tomography orbit showed metallic foreign bodies abutting the globe but not causing globe rupture (Fig. 2A: axial view; Fig. 2B: coronal view; Fig. 2C: sagittal view). The foreign bodies were removed (Fig. 1. inset) and the lid and canalicular repair was done. Pars plana vitrectomy was done to clear the vitreous haemorrhage. During the procedure, fibrogliotic bands with pigmentary alterations and multiple retinal breaks were noticed inferonasally due to coup injury at the site of the impact. Differential diagnoses of chorioretinitis sclopetaria, choroidal rupture and commotio retinae were kept in mind. The breaks in the region of chorioretinitis sclopetaria were lasered using a 532 nm laser. At 12 months of follow up, the visual acuity was 20/40 with attached retina (Fig. 3A and B) and no complaints of epiphora were noted. To the best of our knowledge, the impaction of multiple foreign bodies with stacking in the extra-ocular space has not been reported previously in the spectrum of work-tool related eye injuries. A team approach by oculoplastic and retina surgeons may be required for successful management of complex occupational ocular trauma.Fig. 1: (A) Photograph showing three metallic foreign bodies stacked one above the other in the lower eyelid in the medial aspect. (B) Fundus picture showing diffuse retinal opacification around optic disc and the fundus details are masked by overlying vitreous haemorrhage (inset). Photograph showing three (two are stacked together) 15 mm round smooth disc-shaped brass foreign bodies removed from the orbit.Fig. 2: Computed tomographic scan showing metallic foreign body in the inferior orbit abutting the globe with intact inferior wall of the orbit (A, axial scan, B, coronal scan, C, sagittal scan).Fig. 3: (A) Follow-up facial photograph of the patient showing repaired eyelid after removal of the foreign bodies with puncta well opposed to the globe. (B) Fundus montage of the right eye, after pars plana vitrectomy showing inferonasal chorioretinitis sclopetaria (arrow) with laser done for retinal breaks (arrowheads).Conflicts of Interest: None.

Intravitreal Ranibizumab for Treatment of Posttraumatic Choroidal Neovascularization: a Case Report

An analysis of the case of applying a course of fibrinolytic therapy and one intravitreal injection of an angiogenesis inhibitor in a patient with traumatic rupture of the choroid complicated by choroidal neovascularization (CNV) is presented. Patient B., 20 years old, complained of a lack of objective vision after a blunt injury to his right eye in March 2018. Visual acuity decreased to 0.01 (ETDRS 0 characters). During the examination revealed: partial hemophthalmus, rupture of the choroid, Berlin retinal opacification. Local fibrinolytic conservative therapy with positive dynamics was carried out in the form of increasing visual acuity to 0.3 (ETDRS 21 characters) and partial resolution of hemophthalmus. According to optical coherence tomography angiography (OCTA), minimally active CNV was detected. Due to the weak activity of the pathological process, a decision was made on dynamic observation. A follow-up examination in August 2018 revealed an increase in CNV activity according to OCTA and fluorescence angiography (FAG), in connection with which intravitreal administration of ranibizumab (lucentis) was performed. Subsequently, the patient was under dynamic observation for one year. Positive dynamics was revealed in the form of an increase in visual acuity, first to 0.7 (ETDRS 48 characters) 3 months after intravitreal injection, and after a year — to 0.9 (ETDRS 55 characters). After treatment according to OCTA and FAG, the activity of CNV was not determined. Despite the favorable result of treatment, further monitoring of the patient is necessary, since the long-term prospects for maintaining the achieved high visual functions remain unclear due to the insufficient experience in treating patients with this pathology according to the literature.

Fulminant Progressive Atypical Acute Zonal Occult Outer Retinitis

Purpose: To report a case of unilateral progressive atypical acute zonal outer retinitis in a healthy young female.Case summary: A 32-year-old healthy woman presented with visual disturbance in the left eye for 1 week. Best corrected visual acuity was 0.4 in the left eye. No abnormal findings were detected on brain magnetic resonance imaging and a laboratory work-up. Zonal retinal opacity around the optic nerve disc was noticed in a fundus photo which was consistent with the outer retinal signal defect on optical coherence tomography and a defect in the central visual field from perimetry. Multiple evanescent white dot syndrome was suspected based on fluorescein angiography and indocyanine green angiography. Prednisolone was prescribed. Visual acuity was reduced to hand-motion after 10 days with extended zonal retinal opacity. No virus was detected by multiplex polymerase chain reaction of the aqueous humor. The lesion did not improve despite high-dose intravenous steroid and antiviral treatment.Conclusions: Visual function was lost with the progression of outer retinitis. This case differed from previous cases as the outer retinitis progressed rapidly from the posterior pole to the peripheral retina. It was named fulminant progressive atypical acute zonal outer retinitis.

Miliary tuberculosis: an atypical presentation

Miliary tuberculosis (TB) is a severe form of disseminated TB. In developing countries childhood miliary TB is a significant health problem. Pulmonary TB is the most common type of TB in children. Of all TB cases miliary TB accounts for about 1%. We report a case of paediatric miliary TB with acute presentation in a eleven years old female who presented with fever and cough since 3 days and rapid breathing since one day. Clinical examination showed hepatosplenomegaly, on auscultation chest was clear and air entry bilateral equal, chest x-ray was suggestive of miliary shadows suggestive of TB and it was confirmed by HRCT chest. Laboratory studies revealed anaemia and elevated erythrocyte sedimentation rate (ESR). Tuberculin test was negative, gastric lavage for acid-fast bacilli Gene-Xpert was positive for mycobacterium tuberculosis. Fundus examination revealed bilateral small, white sub retinal opacities with the classical appearance of choroidal tubercles. The diagnosis of Miliary TB was confirmed and the patient was started on anti TB therapy.

Subclinical retinal angiopathy associated with hereditary transthyretin amyloidosis – assessed with optical coherence tomography angiography

Background Retinal angiopathy is a known ocular manifestation of hereditary transthyretin amyloidosis (ATTRv). Optical coherence tomography angiography (OCT-A) is a recent noninvasive imaging technique, used in other retinal vascular diseases. Our purpose was to analyse subclinical changes in retinal vessels, with OCT-A, in patients with ATTRv amyloidosis. Methods Observational cross-sectional study in Centro Hospitalar e Universitário do Porto in the cohort of patients with genetic diagnosis of ATTRv. Patients were included if they had just one eye with scalloped iris (the other eye without scalloped iris), postulating eyes were at different stages, in the same patient. Patients were excluded if they had other manifestations of ocular ATTRv amyloidosis, namely clinical retinal angiopathy and/or vitreous opacities. The group of eyes with scalloped iris were compared with eyes without scalloped iris, using paired tests. Values are shown as Δ = mean difference between groups; p = p-value, d = Cohen’s d for effect size measurement. Results Twenty-four patients (24 eyes in each group) were included. Mean age was 46.5 ± 5.0 years. Eyes with scalloped iris showed attenuated retinal vascular network: larger foveal avascular zone (FAZ) area (Δ = +0.02 mm2, p = 0.002, d = 0.70); decreased foveal vascular density (Δ = –3.57%, p = 0.001, d = –0.75); superficial (Δ = –1.50%, p = 0.049, d = –0.43) and deep (Δ = –2.53%, p = 0.023, d = –0.50) plexus vascular density. Acircularity index was superior in scalloped iris eyes (Δ = 0.04, p = 0.004, d = –0.65), representing an abnormal FAZ morphology. Conclusion Scalloped iris in ATTRv eyes are associated with a more advanced subclinical retinal angiopathy, than eyes without scalloped iris. Our results identify for the first time and in vivo, early changes in retinal vessels in ATTRv amyloidosis. Henceforward, OCT-A may play a role in the evaluation of ATTRv patients oculopathy and the effectiveness of future eye targeting treatments.

Polycythemia causing posterior segment vascular occlusions

A 44-year-old male patient presented with features suggestive of transient central retinal artery occlusion (CRAO) followed by permanent CRAO and lateral posterior ciliary artery occlusion. He had diagnostic features of polycythemia vera (PV). When presented for the first time, the patient had features of ocular ischemia such as ocular pain, conjunctival congestion, and retinal opacification but with normal arm-to-retina time and normal arteriovenous transit time. During the second presentation, he had ocular pain, congested conjunctiva, retinal opacification, cherry red spot with box-carrying of retinal vessels, and choroidal infarct (Amalric's sign). He had lost light perception in that eye. Patients with polycythemia are prone to multifocal vascular occlusions and this can be the presenting feature in PV. A timely diagnosis and prompt management can prevent these repeated thromboembolic occlusive episodes.

Central retinal artery occlusion in the case of traumatic orbital cellulitis

Vision can be lost after orbital infection as a result of optic nerve atrophy, central retinal artery occlusion (CRAO). We report such a case. We present a case report CRAO secondary to periorbital cellulitis. A 52-years-old male patient attended our clinic with left upper eyelid edema, hyperaemia, pain and visual loss. History revealed that he had an ocular surface trauma with cement to his left eye 7 days before. Fundus examination showed patchy filling of the branches of the central retinal artery, retinal opacification at the posterior pole and cherry red spot at the macula. His left visual acuity was declined to no perception of light. There was no clinical improvement after 7 days teatment. Orbital cellulitis did not respond to all treatment and magnetik resonance imaging demonstrated subperiosteal abscess at the posterior-superior orbital wall. We report a case of orbital cellulitis following an ocular surface trauma resulting in the rare complication of central retinal artery occlusion.

Background ophthalmological changes following subretinal injection in the brown Norway rat

PurposeThe purpose of the study was to evaluate the background changes associated with transscleral subretinal injection in Brown Norway (BN) ratsMethodsFifteen BN rats received a bilateral transscleral subretinal injection of saline at a volume of 6 μL while under isoflurane anesthesia. The eyes were examined by slit lamp and indirect ophthalmoscope the day following injection and 1, 2, 3, 4, 8 and 12 weeks post injectionResultsProcedure‐related changes included the following observations: Transient corneal opacities occurred in 16/30 eyes that were considered related to the anesthesia. Cataracts developed in 5/30 eyes associated with lens trauma at the time of dosing. Slight vitreous hemorrhages occurred post dose in 28/30 eyes, resolving in all but 2 eyes by 4 weeks. An area of focal depigmentation of the retina/choroid or white focal retinal opacity was seen at the needle insertion site at the retina in 22/30 eyes, resolving by 4 weeks for 13 eyes and persisting up to 12 weeks for the remaining 7. In the bleb itself, there were focal areas of irregular pigmentation in 13/30 eyes resolving in all but 2 eyes by week 4. The remaining 2 persisted up to week 12. This was considered secondary to the physical neuro‐retinal separation caused by the bleb formation. Slight retinal/choroidal hemorrhages were also seen at the injection site in most eyes up to week 4ConclusionsIn conclusion, transscleral subretinal injection in BN rats generally resulted in slight ocular trauma that resolved in most eyes by 4 weeks post injection. It is important to take these changes into account when designing the study and evaluating therapeutics administered by this dose route.

Development and reliability of retinal arteriolar central light reflex quantification system: a new approach for severity grading.

To describe the methodology and assess the reliability of novel computer-based semiautomated software that quantifies retinal arteriolar central light reflex (CR) from digital retinal photographs. A total of 150 optic disc-centered digital color retinal photographs were selected from a population-based cross-sectional study of persons aged 40 to 80 years (the Singapore Malay Eye Study [SiMES]). Computer-assisted software was developed to quantify retinal arteriolar CR by selecting vessel edge points semiautomatically. This software then automatically computes the CR, vessel diameter, and the CR-to-vessel diameter ratio (CRR). Reliability was assessed using the intraclass correlation coefficient (ICC) and Bland-Altman plots. Multiple linear regression analyses were performed to assess the associations between CRR and systemic and ocular factors, to further validate the novel software. The ICCs for the intergrader and intragrader CRR measurement were 0.76 (95% confidence interval [CI] 0.53-0.89) and 0.86 (95% CI 0.67-0.94), respectively. The ICC for intravisit repeatability was 0.87 (95% CI 0.71-0.95). In the multivariate model, a higher CRR was associated with elevated mean arterial blood pressure (per 10 mm Hg increase) (β = 0.017, P < 0.001). Quantitative assessment of retinal arteriolar wall opacification is a reliable method using a new computer-assisted system. This new CRR measurement system is a potentially useful tool to study retinal arteriolar abnormalities with systemic diseases.

Five‐year incidence of branch retinal vein occlusion and its systemic and retinal risk associations: The Funagata study

AbstractPurpose To determine retinal and systemic risk associations of branch retinal vein occlusion (BRVO) over 5 years in adult population‐based cohort in Japan.Methods The Funagata study is a population‐based longitudinal cohort study in Yamagata, Japan. In 2000‐2, we performed baseline survey including fundus photography and systemic examination. In 2005‐7, 5‐year follow‐up survey was performed and newly developed BRVO cases were determined. There were 954 persons who attended both baseline and 5‐year follow‐up survey; 878 persons had good quality fundus photographs suitable for grading (right eye only). Using multiple logistic regression models, retinal and systemic risk characteristics were determined.Results Mean age of study participants were 58.9 years old and 57.2% were women. Prevalence of diabetes and hypertension was 4.0% and 32.2%, respectively. There were 12 newly developed BRVO over 5‐ years (1.37%, right eyes only). In multiple logistic regression models including those significantly associated systemic risks, older age (adjusted odds ratio [OR] 1.15 per 1 year, 95% confidence interval [CI] 1.02‐1.31, p=0.026) and waist‐to‐hip ratio (adjusted OR 6.15 per 0.1, 95%CI 1.50‐25.3, p=0.012) remained as significant risk characteristics. Retinal vessel opacification was significantly associated with incident BRVO after adjusting for systemic risk characteristics.Conclusion In addition to older age, larger waist‐to‐hip ratio was identified as a modifiable systemic risk characteristic of 5‐year incident BRVO. Retinal vessel opacification was also identified as a risk characteristic in the retina; there is a potential as a marker to predict BRVO. Commercial interest

Prepapillary vascular loops complicated by suspected macroaneurysm rupture.

We present a case of prepapillary vascular loops complicated by a suspected macroaneurysm rupture which was treated with intravitreal bevacizumab (IVB). A 62-year-old woman presented with decreased vision and myodesopsia in her left eye. Her best-corrected visual acuity (BCVA) was 0.6 in the left eye. Fundus examination disclosed an elevated, round, and reddish lesion, retinal hemorrhage at the superior aspect of the optic disc, retinal opacification along the superior branch retinal artery, and a small vitreous hemorrhage. Optical coherence tomography showed a serous retinal detachment, and indocyanine green angiography demonstrated prepapillary vascular loops and a hypofluorescent area with hyperfluorescent margins. These findings suggested the presence of a macroaneurysm. No filling of the dye in the aneurysm-like dilatation suggested a blockage of the lumen with a thrombus which might be associated with a branch retinal artery occlusion (BRAO). A diagnosis of prepapillary vascular loops complicated by a suspected macroaneurysm rupture and BRAO was made. Because of a persistent serous retinal detachment, IVB was performed. One month later, the BCVA improved to 1.0. Fundus examination disclosed an organized yellowish-white macroaneurysm and resolution of the serous retinal detachment. We recommend careful monitoring of patients with prepapillary vascular loops because of complications such as macroaneurysm rupture and BRAO.

Changing Perspectives in Classifications of Hypertensive Retinopathy.

Hypertensive retinopathy represents the ophthalmic findings of end organ damage secondary to systemic arterial hypertension. The eye is a target organ as well as an established prognostic indicator of systemichypertension. Based on ophthalmoscopically visible alterations, several classifications, the majority of them grading hypertensive fundus changes into four stages have been suggested. The recognition of hypertensive retinopathy is important in cardiovascular risk stratification of hypertensive individuals. The review evaluates the changing perspectives in classification & prognostic significance of fundal lesions. consists of retinal vascular changes that are pathologically related to both transient & persistent microvascular damage from elevated blood pressure. Ocular changes can be the initial finding in an asymptomatic patient with hypertension necessitating primary referral. In other instances, asymptomatic patient may be referred to an ophthalmologist for visual problems caused by hypertensive changes. Elevation of systemic blood pressure causes both focal and generalized constriction of retinal arterioles mediated by autoregulation. These findings are relatively common in long standing hypertension. A prolonged duration of high blood pressure can be associated with a breakdown of inner blood retinal barrier with extravasation of plasma & RBCs . Retinal haemorrhages, cotton wool spots, intraretinal lipids & in severe cases , the development of macular star configuration of intraretinal lipid can be seen. Although its name implies only retinal involvement, changes in both choroid & optic nerve are observed. When choroidal vessels are severely affected by elevated blood pressure, as in acute hypertension, fibrinoid necrosis of choroidal arterioles can cause occlusion of areas of choriocapillaris, with a subsequent breakdown of outer blood retinal barrier. Ocular findings in accelerated hypertension are divided into three distinct categories: hypertensive retinopathy, hypertensive choroidopathy & hypertensive optic neuropathy. Ophthalmic findings in acute malignant hypertensive retinopathy include focal arterial narrowing, cotton wool spots, intraretinal transudates , macular edema and retinal haemorrhages. Cystoid macular edema, lipid deposits and arteriolar changes are signs of malignant hypertensive retinopathy (2) . Cotton wool spots are fluffy, elevated, tan white areas of retinal opacity occurring within a few disc diameters of optic nerve, caused by occlusion of terminal retinal arterioles. Cotton wool spots typically resolve in 3-6 weeks and are associated with permanent nerve fiber layer loss in the vicinity of the lesion (2) . Periarteriolar intraretinal transudates are tan white retinal lesions which resolve without residual retinal damage in 2-3 weeks (3) . Macular edema and subretinal fluid are retinal findings related to hypertensive choroidal changes affecting the retinal pigment epithelium, with alterations in the blood retinal barrier. Clinical changes from hypertensive choroidopathy are directly related to the release of endogenous vasoconstrictor agents (eg.,angiotensin II, epinephrine, vasopressin) during systemic hypertension. Angiographically, there is delayed, patchy choroida lfilling

IN VIVO DETECTION OF ACUTE ISCHEMIC DAMAGES IN RETINAL ARTERIAL OCCLUSION WITH OPTICAL COHERENCE TOMOGRAPHY

To describe characteristic findings of acute retinal ischemic damage in optical coherence tomography. Eighteen cases of acute retinal arterial occlusion with available fundus photography, optical coherence tomography, and/or fluorescein angiography in the early phase (<1 month) with more than 2 months follow-up were reviewed. A site-to-site analysis between optical coherence tomography morphology and correlating fundus images were done on each visit. Retinal opacities at first presentation were vague to mild opacity in four eyes, moderate (affecting visibility of underlying choroidal vessels) in seven, severe (yellow to whitish) in five, and very severe (chalky white) in two. These changes eventually disappear within 1 month (8 of 9 eyes). Inner retinal hyperreflectivity and a "prominent middle limiting membrane" in optical coherence tomography were consistently noticed up to 1 month showing regional correlation with the retinal opaque areas and was readily identified even in areas with vague or disappeared retinal opacities. Later, inner retinal atrophic changes replace these ischemic optical coherence tomography signs. A prominent middle limiting membrane sign is a useful indicator of acute ischemic retinal damage, especially in cases showing subtle or resolved retinal opacities before the onset of atrophic changes.

Central retinal artery occlusion and cerebral stroke

Sir, Aspects of the review by Varma and colleagues1 conspire to amplify the confusion that surrounds central retinal artery occlusion (CRAO). First, they report that a foveal cherry-red spot is present in 90% of eyes examined within 1 week of CRAO onset, whereas only 58% show concomitant macular opacification. Surely these ‘classic' CRAO signs must co-exist? Second, Varma and colleagues discuss ‘transient' CRAO, a small subgroup of eyes in the Iowa CRAO classification characterised by CRA reopening by the time of initial presentation and fluorescein angiography.2, 3 They state that ‘transient' CRAO is ‘analogous to a transient ischaemic attack affecting the eye' since ‘restoration of blood flow … results in symptom resolution'.1 This is not the case. The Iowa classification dispenses with terminological convention by labelling events as ‘transient' even though complete reversal of symptoms and signs is precluded by a duration of ischaemic anoxia exceeding 4 h (inner retina's maximum survival time).4 They also state that ‘transient' CRAO presents ‘greatly varied fundus findings'.1 This is not the case. If the duration of ‘transient' CRAO exceeds 4 h, the ‘classic' signs will persist for at least a week. Alternative presentations in the form of ‘scattered patches of retinal opacity'2, 3 usually signify ‘partial', not ‘transient', CRAO.5 Third, Varma and colleagues believe ‘only a rare subgroup of individuals have viable tissue' in the inner retina by 24 h from CRAO onset.1 This is not the case. Although the survival time of anoxic tissue in the posterior pole has been exceeded, this ‘core' of infarction will be surrounded by a zone of critically hypoxic but viable tissue (the ‘ischaemic penumbra'), just as in cerebral stroke. Unlike penumbral cerebral cortex, however, penumbral retina can persist indefinitely.5 Reperfusion of this tissue explains the recovery of the ERG b-wave after CRA unclamping following 4 h of CRAO.4 It can also account for the visual improvement frequently attributed to ‘natural history' in patients,1, 2, 3 provided neural connectivity is maintained between reoxygenated penumbra and optic nerve. However, if the CRA does not reopen and cilioretinal collaterals are not formed, the enduring penumbral state of the tissue will stimulate intraocular neovascularisation (developing in 15–20% of CRAO eyes).5

Peripapillary retinal thermal coagulation following electrical injury

In this study, we have presented the case report of a 20 year old boy who suffered an electric injury shock, following which he showed peripapillary retinal opacification and increased retinal thickening that subsequently progressed to retinal atrophy. The fluorescein angiogram revealed normal retinal circulation, thus indicating thermal damage to retina without any compromise to retinal circulation.

Primary branch retinal artery occlusion in idiopathic retinal vasculitis, aneurysms, and neuroretinitis syndrome associated with hyperhomocysteinemia.

The purpose of this study was to report primary branch retinal artery occlusion in a case with idiopathic retinal vasculitis, aneurysms, and neuroretinitis syndrome. Review of medical case records, color fundus photographs, and fundus fluorescein angiography of a 23-year-old man diagnosed with idiopathic retinal vasculitis, aneurysms, and neuroretinitis. A 23-year-old man presented with sudden painless decreased vision in right eye since 1 day. Ocular examination revealed a best-corrected visual acuity of counting fingers 1 feet in the right eye and 20/20 in the left eye, relative afferent pupillary defect in the right eye, 1+ vitreous cells in both eyes, optic disk neovascularization with massive peripapillary and perivascular lipid exudation, and occluded smaller vessels in both eyes. In addition, there was an area of retinal opacification in the posterior pole along the inferotemporal arcade in the right eye. The patient underwent color fundus photography, fluorescein angiography, and a detailed systemic workup. Fundus fluorescein angiographic features were suggestive of idiopathic retinal vasculitis, aneurysms, and neuroretinitis in both eyes with branch retinal artery occlusion in the right eye. Detailed systemic workup revealed raised serum homocysteine levels. The patient underwent scatter retinal photocoagulation in both eyes and also was started on folic acid and pyridoxine supplementation. At 1 year of follow-up, the best-corrected visual acuity in the right eye improved to 20/60. Posterior segment examination showed reduced exudation, resolution of optic disk neovascularization in both eyes, and clearing of retinal opacification in the right eye. Also, the levels of serum homocysteine decreased over 1 year. Primary branch retinal artery occlusion can be an atypical presentation of idiopathic retinal vasculitis, aneurysms, and neuroretinitis syndrome. Such a case should be thoroughly investigated for underlying hypercoagulable state. Also, a careful long-term follow-up is required for these patients to prevent any neovascularization sequelae.