Reappearance of excentric persistent fetal vasculature stalk following laser treatment in a patient with type 1 retinopathy of prematurity.

PURPOSE: In this report, we aim to present an unusual reappearance of hyaloidal artery remnant with atypical localization during the follow-up of an infant who underwent indirect laser photocoagulation for type 1 ROP. METHODS: Retrospective case report. RESULTS: We report a case of reappearance of an eccentrically located hyaloidal stalk in the macular area during the follow-up period, 2 weeks after laser photocoagulation for type 1 ROP subsequently progressed to cause foveal distortion, which is successfully removed with a lens-sparing vitrectomy. CONCLUSIONS: To the best of our knowledge, there is no similar case in the literature. In the presence of fibrovascular proliferation extending into the vitreous, especially in premature infants, it should be kept in mind that this may be a reappearance of PFV and it may not always be located on the optic disc.

Orbital Fibrotic Band as Cause of Monocular Elevation Deficiency.

Monocular elevation deficiency is a congenital, unilateral inability of elevation. It is classified as innervational, restrictive, or combine types. Here, we report a rare case of monocular elevation deficiency who had 60 PD left hypotropia and left ptosis with limited elevation (-5) both on abduction and adduction. Orbital MRI revealed a hypointense fibrotic band between the superior oblique and superior rectus muscles extending obliquely in the superonasal direction between the sclera and orbital roof. She was successfully treated after severing the fibrotic band between the sclera and bony orbit.

Evaluation of fixation characteristics in amblyopia using microperimetry.

PURPOSE: To evaluate fixation characteristics in amblyopia using macular analyzer integrity assessment (MAIA) microperimetry and to investigate the factors affecting fixation stability. METHODS: This prospective, cross-sectional study enrolled a total of 58 amblyopic patients who were between 8 and 55 years old. Average threshold macular sensitivity (AT) and fixation characteristics were assessed using MAIA microperimetry. Two Bivariate contour ellipse area (BCEA) fixation indices (63% and 95% proportional values) and the percentage of fixation points within 1° and 2° from the fovea (P1 and P2) were used to assess fixation stability. Non-amblyopic fellow eyes were used as the control group for comparison. RESULTS: AT and fixation stability indices (P1, P2, BCEA 63%, BCEA 95%) were worse in the amblyopic eyes than in the fellow eyes (p < 0.05, for all indices). There was a moderate positive correlation between best corrected visual acuity (BCVA), and AT, and P2, and a moderate negative correlation between BCVA, and BCEA indices. 48% of the eyes were eccentrically fixating (the percentage was 25% in the anisometropic group, 52% in the strabismic group, and 69% in the combined group) and 32% in the non-amblyopic eye (p = 0.052). The preferred fixation eccentricity in amblyopic eyes was significantly greater than the non-amblyopic eyes (p = 0.004), and there was a negative correlation between preferred fixation eccentricity and BCVA (p = 0.012, r = - 0.327). CONCLUSIONS: Our data showed a decrease in fixation stability, a positive correlation between fixation stability and BCVA, and a negative correlation between preferred fixation eccentricity and BCVA in amblyopic eyes.

Does methylphenidate treatment affect functional and structural ocular parameters in patients with attention deficit hyperactivity disorder? - A prospective, one year follow-up study.

Purpose: Methylphenidate hydrochloride, which blocks the reuptake mechanisms of dopamine and norepinephrine, is used in attention deficit hyperactivity disorder (ADHD) treatment. Methylphenidate has many general side effects including ocular findings. In this study, we investigated the long-term effects of methylphenidate treatment on functional and structural ocular parameters. Methods: In this prospective study, children with ADHD were evaluated. All patients underwent a detailed ophthalmic examination before methylphenidate treatment. All patients were examined in the 3rd, 6th, 9th, 12th months of methylphenidate treatment. Visual acuities, color vision, pupil diameters, static, dynamic and cycloplegic retinoscopy, intraocular pressure (IOP), anterior chamber depth (ACD), axial length (AL) were evaluated and recorded. Results: A total of 22 children were included in this study. The best-corrected visual acuities (BCVA) of all patients for both eyes were 0.0 logMAR, and 90.9% of patients had blue-purple color weakness before the treatment. After 1 year of treatment, none of the patients had any change in BCVA and color vision. However, an increase in myopic values of static retinoscopy and a decrease in hyperopic values of cycloplegic retinoscopy were found. Additionally, accommodation capacities were found to be decreased and AL was found to be increased significantly for both eyes. Pupil diameter, IOP, and ACD values did not change significantly. Conclusion: Our results suggest that patients with ADHD may have blue color vision deficiencies because of the decreased retinal dopamine levels. Additionally, structural and ocular parameters, especially accommodation capacity, may be affected by methylphenidate treatment.

Isolated abducens nerve palsy due to COVID-19.

Although coronavirus disease-2019 (COVID-19) is mainly a respiratory system disease, neurological complications due to peripheral and central nervous system involvement may be seen in these patients. In this case report, we described a patient with isolated abducens nerve palsy after COVID-19. The patient was a healthy 28-year-old man who developed isolated abducens nerve palsy 10 days after COVID-19. He had no systemic risk factors. He had 20 PD left esotropia (ET) at distance and 16 PD left ET at near in primary position and ET increasing to 25 PD in left gaze. He had left abduction deficiency. His cranio-orbital magnetic resonance imaging findings were normal. He was diagnosed as left isolated abducens nerve palsy and his findings were recovered after 2 months. COVID-19 may cause ocular motor nerve palsies. Although the pathological mechanism remains unclear, direct viral invasion, inflammatory and immune mechanisms may play role. Further case reports and studies are needed to support these findings.

Ocular and cerebral causes of visual impairment in young children and a new scoring system to evaluate visual function.

PURPOSE: Childhood blindness is important cause contributing to the burden of blindness. It is necessary to identify the most frequently observed diseases in different populations. We aimed to demonstrate clinical features of low vision children and to evaluate the factors affecting visual function by a new visual function scoring system. METHODS: Two hundred forty nine children between the age of 6 months and 3 years were included. Visual function was scored from 0 to 15 according to; response to threat, light, object, presence of fixation, duration of fixation, following of light and object in horizontal, vertical, oblique, and circular gazes, optokinetic nystagmus. Patients were classified according to neurological diagnosis and cranial magnetic resonance imaging findings. Correlation between visual function score and ocular and neurologic findings were evaluated. RESULTS: While 136 patients (54.6%) had cerebral visual impairment (CVI), 89 (35.7%) had ocular pathology, 24 patients (9.6%) had combined pathology. The most common ocular and cerebral pathologies were oculocutaneous albinism (23.9%) and hypoxic ischemic encephalopathy (HIE) (27.5%), respectively. Patients with CVI had lower visual function than ocular pathologies. Neurological structural disorders and HIE had worse visual function. Widespread involvement of brain had lower visual function score. Seizure negatively affected visual function. CONCLUSIONS: Cerebral causes were found in approximately half of infants and children with low vision who were referred to our center for visual habilitation. The visual function scoring system we developed in this study will provide an opportunity to be objective in the follow-up of babies and in evaluating the effectiveness of visual habilitation programs.

Visual habilitation in young children with visual impairment.

PURPOSE: To evaluate the effectiveness of the visual habilitation programme in improving the visual functions of visually impaired children under 3 years old. METHODS: Case records of children with visual impairment (VI) who had at least 1 follow-up visit were reviewed. Children's visual functions were scored between 0 and 15 based on mainly fixation and following skills. Differences in patients' visual function score (VFS) between the time of the presentation and the last follow-up visit were recorded. RESULTS: One hundred thirty children with VI (63 male and 67 female) were identified. The mean age at the presentation was 13.94 ± 9.23 months, and the mean follow-up was 12.79 ± 9.4 months. Forty of the patients had ocular, 70 of them had cerebral, and 20 of them had combined VI. Correlations were found between the age of the patients at the presentation and the initial VFS; and gestational age and the initial VFS (p Ë‚ 0.001, r = 0.332; p Ë‚ 0.05, r = 0.262, respectively). Vision improvement was noted in ocular, cerebral and combined VI groups. No significant difference among the groups was found (p = 0.430). There was a significant difference between the change in the VFSs of those who attended the special education and rehabilitation centre regularly for 2 h a week and had regular visual stimulation for 8-10 sessions every day at home and those who did not go to the centre and did not receive any visual stimulation by their parents at home (p Ë‚ 0.001). CONCLUSIONS: The visual functions of visually impaired children can be improved by habilitation, which includes visual stimulation programmes.

Diplopia After Migraine Surgery.

A 46-year-old man with refractory migraine headache was treated with decompressive migraine surgery of the supraorbital and supratrochlear nerves. Postoperatively, he reported diplopia that got better on left head tilt. After ophthalmological examination, a diagnosis of right superior oblique palsy was made. The aim is to report the first case of superior oblique muscle or trochlea damage that may have occurred because of inadvertent entry through the orbital septum into the right superior orbit.

Ocular Findings of Pediatric Dry Eye Related to Graft-Versus-Host Disease

Objectives: To evaluate the frequency and findings of dry eye associated with ocular graft-versus-host disease (GVHD) in pediatric hematopoietic stem cell transplantation (HSCT) patients. Materials and Methods: Retrospectively the records of pediatric patients with ocular GVHD were evaluated and ophthalmologic examination findings as well as Schirmer test results, tear film break-up time, and corneal staining grades were recorded. In severe dry eye patients topical cyclosporine-A was prescribed and the results were evaluated. Results: GVHD was detected in 51 (23.4%) of 218 HSCT patients, 4 of whom died during follow-up. Thirty (63.8%) of the remaining 47 patients had chronic ocular GVHD and 4 patients with severe dry eye were treated with topical cyclosporine-A with a median follow-up of 12.1 months. Severe dry eye symptoms and findings significantly improved in 2 patients. However, 1 patient had to stop treatment due to side effects. Conclusion: In children, chronic ocular GVHD is a common finding of GVHD after HSCT. Therefore, these patients should be examined periodically for dry eye.

A novel biomarker for increased intracranial pressure in idiopathic intracranial hypertension.

PURPOSE: Changes in optic disc and peripapillary structures associated with optic nerve edema in idiopathic intracranial hypertension (IIH), can be evaluated with spectral domain optical coherence tomography (SD-OCT). We aimed to evaluate the association between increased cerebrospinal fluid (CSF) opening pressure and changes in peripapillary structures detected by SD-OCT and to determine whether these changes can be used to assess the changes in CSF pressure without performing lumbar puncture (LP). STUDY DESIGN: Retrospective study METHODS: We included 54 eyes of 28 patients with bilateral papilledema who had peripapillary SD-OCT imaging within 24 h before the LP. Correlation between CSF pressure and peripapillary OCT parameters including maximal retinal thickness, maximal anterior retinal projection, maximal retinal nerve fiber layer (RNFL) thickness and Bruch membrane opening (BMO) was evaluated. RESULTS: Bruch Membrane opening and maximal RNFL thickness were significantly higher in patients with increased CSF pressure. There exist correlations between CSF pressure and BMO, maximal RNFL thickness and maximal retinal thickness. (Spearman's Rho: 0.791, 0.482 and 0.297, p < 0.001, < 0.001 and 0.029, respectively) The cut off value of BMO for the prediction of increased CSF pressure was 1785 µm, with a sensitivity of 78.8% and a specificity of 81%. The cut off value for maximal RNFL thickness was 174 µm, with a sensitivity of 75.8% and a specificity of 61.9%. CONCLUSION: Bruch membrane opening and maximal RNFL thickness can give an idea about increased CSF pressure values in IIH patients. Thus SD-OCT can be used to detect CSF pressure changes in these patients.

Vascular changes with optical coherence tomography angiography during aura of migraine: A case report.

PURPOSE: To demonstrate macular and optic disk vessel changes by optical coherence tomography angiography during and after a migraine attack with aura. METHODS: Case report. RESULTS: A 34-year-old healthy female patient was evaluated by optical coherence tomography angiography imaging during visual aura with phosphenes in the left visual field. Optical coherence tomography angiography imaging showed diffuse narrowing of the retinal vessels, decreased radial peripapillary capillary density, and decreased superficial and deep foveal vessel density in the right eye. These changes improved 3 hours after visual aura. The patient suffered from right eye pain and right-sided headache, which are typical for migraine, after the visual aura. CONCLUSION: These findings indicate that blood flow during migraine attack is reduced not only in the brain but also in the eye. Eye pain in migraine patients may be due to decreased blood flow in the eye. Restoring the vascular changes 3 hours after the visual aura suggests that vascular changes may be transient during a migraine attack.

Effectiveness of Low Vision Rehabilitation Using Microperimetric Acoustic Biofeedback Training in Patients with Central Scotoma.

PURPOSE: To evaluate the efficacy of visual rehabilitation with microperimeter biofeedback in patients with central scotoma. MATERIALS AND METHODS: 35 consecutive patients with central scotoma (17 age-related macular degeneration (AMD), 14 Stargardt disease, and 4 cone dystrophy) were included in the study. Visual acuity, reading performance by Minnesota Low Vision Reading Test (MNREAD), quality of life by 25-item National Eye Institute Visual Function Questionnaire (NEI VFQ-25), and fixation analysis by MAIA microperimeter were evaluated before and 1 month after training. The rehabilitation program consisted of 10 training sessions of 10 minutes. RESULTS: The median best-corrected visual acuity (BCVA) was 0.80 logMAR (range 0.3 to 1.3 logMAR). Fifty-nine percent of patients with AMD developed a preferred retinal locus (PRL) nasal to the fovea, and 64% of the patients with Stargardt disease preferred a PRL superior to the fovea. The PRL location in 3 of 4 cone dystrophy patients was nasal to the fovea. The mean PRL distance from the fovea was 7.57 ± 3.61 degrees. Fixation stability improved with P1 values of 22.34 ± 11.81 versus 32.05 ± 18.79 (p = .003) and 95% bivariate contour ellipse area (BCEA) values of 41.6 versus 23.6 (p = .018) before and after training, respectively. There was a significant difference in reading acuity between before and after training (p = 0.008). The overall score and near activities score of NEI VFQ-25 were found to be increased at the end of the rehabilitation (p < 0.001). CONCLUSION: Rehabilitation with acoustic biofeedback in patients with central scotoma looks like a useful technique for improving fixation stability, reading performance and quality of life.

Direct and transsynaptic retrograde degeneration and optic nerve head microvascular changes in patients with hemianopia.

PURPOSE: To investigate optic nerve head (ONH) microvascular changes secondary to transsynaptic retrograde degeneration (TRD), comperatively with direct retrograde degeneration and healthy controls. METHODS: Patients with hemianopia due to intracranial lesion included in the study. Intracranial lesion was categorized by location: postgeniculate (causing TRD), chiasmal (causing direct retrograde degeneration). For the postgeniculate lesions, the eye on the same side of the lesion was defined as the ipsilateral eye and the eye on the opposite side as the contralateral eye. Optic disc microvasculature was evaluated with the help of optic coherence tomography angiography. RESULTS: Sixteen eyes of 16 patients with chiasmal lesion, 28 eyes of 14 patients with postgeniculate lesion, and 30 eyes of 30 healthy subjects were included in the study. Ipsilateral eyes of the patients with postgeniculate lesion had decreased vessel density at the temporal sectors compatible with the affected nasal side of the visual field. Contralateral eyes showed no reduction of the vessel density at the affected nasal sectors. The eyes with chiasmal lesions had decreased vessel density at the peripapillary region and nasal half of the ONH compatible with temporal hemianopia. Vascular changes in the chiasmal lesion were more prominent than those of the postgeniculate lesion. Retinal nerve fiber layer and ganglion cell complex thickness were reduced. CONCLUSION: Vessel density of ONH was reduced in patients with homonymous hemianopia, providing evidence for TRD secondary to acquired postgeniculate lesion. Direct retrograde degeneration was more prominent in affected sectors when compared to TRD.

Optical Coherence Tomography Angiography Findings in Long-Term Follow-up of Leber's Hereditary Optic Neuropathy: Report of Two Cases.

Leber's hereditary optic neuropathy (LHON) is thought to be a neurovascular disease due to presence of vascular changes in asymptomatic patients. Here we present 2 patients in whom optical coherence tomography angiography (OCTA) imaging demonstrated capillary drop-out areas and decreased radial peripapillary capillary (RPC) density in the quadrants that had thinner retinal nerve fiber layer (RNFL) in OCT images. Progressive decrease in RNFL and RPC density were shown in each patient at month 12 and 30 of follow-up. Following up patients with OCTA imaging in the future will provide insight into the pathogenesis and prognosis of LHON.

Evaluation of retinal vessel density and choriocapillaris flow in migraine patients with and without aura.

PURPOSE: Migraine is thought to be a neurovascular disorder and increases the likelyhood to develop ischemic complications. Studies have shown that vascular disorders such as ischemic optic neuropathy, retinal artery and vein obstructions are more common in patients with migraine. This study aimed to evaluate the differences between retinal and optic disc microvasculature between migraine patients with and without aura and healthy controls using optical coherence tomography angiography (OCTA) imaging. METHODS: Thirty-three patients with migraine and 28 healthy subjects were included in this prospective cross sectional study. Optical coherence tomography angiography imaging was performed for the macula and optic disc. Vessel densities (VD) and choriocapillaris flow values were compared between three groups: control group, migraine with aura (MWA), and migraine without aura (MWOA). RESULTS: There was no difference between the three groups for the VDs of the foveal, perifoveal, parafoveal, and the whole area. The choriocapillaris flow of patients with MWA was significantly less than that of the MWOA and control groups. The VDs of the optic disc revealed no significant difference between the three groups. CONCLUSION: A lack of choriocapillaris autoregulatory mechanisms may be a possible cause of the decrease in choriocapillaris flow in patients with MWA.

Brain abnormalities in infantile esotropia as predictor for consecutive exotropia.

Cerebral palsy, neurological abnormalities, prematurity or periventricular lesions may affect motor and sensory fusion mechanisms that favorably control eye alignment. White matter damage of immaturity (WMDI) is a form of white matter brain injury characterized by the necrosis of white matter near the lateral ventricles. In these cases, it is difficult to establish fusion after strabismus surgery and consecutive deviations may be seen more frequently especially in association with WMDI. The aim of this study is to evaluate and compare the cerebral magnetic resonance imaging (MRI) findings in operated infantile esotropia cases with and without consecutive exotropia and to relate them to the occurance of consecutive exotropia.Seventeen patients that had consecutive exotropia after bilateral medial rectus recession surgery for infantile esotropia were included in this study (group 1) and patients that were operated with the same diagnosis with a successful surgical outcome (≤10 PD of deviation) were recruited as group 2. Age, sex, consanguinity, associated systemic and neurological diseases, prematurity, visual acuity, angle of deviations at first visit, at last and follow-up visit and after surgery, cycloplegic retinoscopy, fundus and cerebral MRI findings were recorded. Demographic and clinical findings of patients in two groups and MRI findings were evaluated and compared.The mean age at the time of first examination was 8.21 ± 6.62 and 7.45 ± 4.94 months in infantile esotropia patients with (group 1) and without consecutive exotropia (group 2), respectively. The mean cycloplegic refractive errors (+1.92 ± 1.57 D vs. +2.30 ± 1.10 D), the mean preoperative angle of deviation (46.33 ± 18.8 PD vs. 34.8 ± 12.5 PD), sex, percentage of consanguinity, percentage of prematurity, presence of latent nystagmus, dissociated vertical deviation and amblyopia and fundus findings were similar in both groups. Patients with consecutive exotropia had a mean deviation angle of 37.5 ± 9.48 PD postoperatively. Cerebral MRI findings were consistent with WMDI (three patients), myelinization delay (one patient), septooptic dysplasia (one patient) and periventricular cysts (one patient) in group 1. Cerebellar hemispheres and vermis hypoplasia (one patient), myelinization delay (one patient), cerebellar atrophy (one patient) were the MRI findings of patients in group 2.White matter damage of immaturity was only present in the consecutive exotropia group. This finding may suggest that WMDI can be a risk factor for consecutive deviation in infantile esotropia patients.

Fundus Autofluorescence Changes in Age-related Maculopathy

Objectives: The aim of this study was to describe the fundus autofluorescence (FAF) findings of age-related maculopathy and risk patterns associated with FAF changes. Materials and Methods: FAF images of 150 eyes with age-related maculopathy were evaluated retrospectively. FAF patterns were classified as normal, minimal change, focal increase, patchy, linear, lace-like, reticular, and speckled pattern. Correlation between patterns and visual acuity, pattern associations at initial visit, and focal atrophy development and pattern alterations during follow-up were evaluated. Results: At initial examination, 33.3% of the eyes showed no FAF pattern. In the other eyes, the most common patterns were reticular, focal increase, and patchy pattern at rates of 18%, 14.7%, and 11.3%, respectively. There was no correlation between pattern and visual acuity at initial visit. Two coexisting patterns were observed in 4.6% eyes, and the most common pattern in these combinations was reticular pattern (85.7%). Pattern alterations were observed in 5.3% of the eyes during follow-up. Half of these alterations involved transformation to reticular pattern or addition of reticular pattern to the initial pattern. In addition, 13.3% of the eyes developed focal atrophy during follow-up. Development of focal atrophy was more common with focal increase and reticular pattern, with rates of 45% and 30%, respectively. Conclusion: Presence of reticular pattern may be a risk factor for change and progression of FAF findings in age-related maculopathy.

Results of Screening in Schools for Visually Impaired Children.

OBJECTIVES: The aim of this study was to identify the causes of visual impairment in children attending schools for students with visual impairment and to identify children suitable for treatment and rehabilitation. MATERIALS AND METHODS: All students were examined in our department by a pediatric ophthalmologist and an ophthalmologist experienced in low vision and visual rehabilitation. The children's medical histories were recorded. All children underwent ophthalmological examination including visual acuity measurement, anterior segment and dilated fundus evaluation, retinoscopy with cycloplegia, and intraocular pressure measurement. The causes of visual impairment were grouped as avoidable and unavoidable. Children with residual visual acuity better than 20/1250 were included in the low vision rehabilitation programme. RESULTS: A total of 120 patients were evaluated and 79.2% were legally blind (visual acuity less than 0.05), 18.4% had low vision (visual acuity between 0.05 and 0.3), and 0.8% had normal vision (>0.3). The main causes of visual impairment were retinal dystrophies (24.2%) and retinopathy of prematurity (17.5%). Of all diseases related to visual impairment, 27.6% were avoidable. Improvement in visual acuity was achieved with low vision aids in 57.5% of all patients. CONCLUSION: The incidence of visual impairment due to avoidable causes can be decreased by ophthalmic screening. Treatment of these children in the early stages of visual development can improve visual acuity. Even in cases with delayed diagnosis, low vision aids are important for visual and neurobehavioral development, and these programmes may improve quality of life and education in these children.

Bilaterally Diffuse Lacrimal Gland Involvement: Initial Presentation of Systemic Sarcoidosis.

Orbital involvement in systemic sarcoidosis is a rare condition. We report a case of orbital sarcoidosis with bilaterally huge lacrimal gland involvement as the initial manifestation of systemic sarcoidosis. A 20-year-old woman admitted the ophthalmology department with progressive bilateral upper eyelid swelling for 6 months. The only pathologic finding was the presence of bilateral, symmetrical, solid, lobular masses at the lateral upper eyelids at the location of lacrimal glands. On systemic examination, bilateral parotid and submandibular glands appeared swollen. Magnetic resonance imaging of the orbit revealed bilateral symmetrical diffuse enlargement of the lacrimal glands with maximum and minimum thickness of 11 mm and 7 mm, respectively. The biopsy findings were compatible with sarcoidosis. Although lacrimal gland involvement has been reported in different studies, we for the first time report an unusual case with bilateral diffuse huge lacrimal gland involvement. Normal lacrimal gland thickness is approximately 4-5 mm in magnetic resonance imaging, while our case had bilateral diffuse enlargement of lacrimal glands, which showed maximum and minimum thickness of 11 mm and 7 mm, respectively. Although orbital involvement is uncommon in sarcoidosis, it should be remembered in the differential diagnosis of orbital masses.

Evaluation of Intraocular Inflammation with Laser Flare Photometry in Behçet Uveitis.

PURPOSE: To evaluate the association between intraocular inflammation and laser flare photometry measurements in Behçet disease. METHODS: In total, 45 patients were included in the study. The retrospective chart reviews of patients were performed. The flare levels were compared with the grade of anterior chamber cells, the presence of vitreous cells, the complications of uveitis, and fluorescein angiography scores. RESULTS: The attack group had higher flare intensity; the flare levels were higher in both groups compared with the values of healthy controls. The flare levels were related to the grade of the anterior chamber cells, the presence of vitreous cells and the fluorescein angiography scores. Patients with optic atrophy and/or maculopathy also had higher values. Higher flare values were correlated with poor vision. CONCLUSIONS: Laser flare photometry may reduce the necessity of fluorescein angiography in monitoring subclinical inflammation and may be an indicator of posterior segment activity when fluorescein angiography is not applicable.