August 2021

Ambrosio L, Hansen RM, Moskowitz A, Oza A, Barrett D, Manganella J, Medina G, Kawai K, Fulton AB, Kenna M. Dark-adapted threshold and electroretinogram for diagnosis of Usher syndrome. Doc Ophthalmol 2021;143(1):39-51.Abstract
PURPOSE: To determine the utility of ophthalmology evaluation, dark-adapted threshold, and full-field electroretinogram for early detection of Usher syndrome in young patients with bilateral sensorineural hearing loss. METHODS: We identified 39 patients with secure genetic diagnoses of Usher Syndrome. Visual acuity, spherical equivalent, fundus appearance, dark-adapted threshold, and full-field electroretinogram results were summarized and compared to those in a group of healthy controls with normal hearing. In those Usher patients with repeated measures, regression analysis was done to evaluate for change in visual acuity and dark-adapted threshold with age. Spherical equivalent and full-field electroretinogram responses from dark- and light-adapted eyes were evaluated as a function of age. RESULTS: The majority of initial visual acuity and spherical equivalent results were within normal limits for age. Visual acuity and dark-adapted threshold worsened significantly with age in Usher type 1 but not in Usher type 2. At initial test, full-field electroretinogram responses from dark- and light-adapted eyes were abnormal in 53% of patients. Remarkably, nearly half of our patients (17% of Usher type 1 and 30% of Usher type 2) would have been missed by tests of retinal function alone if evaluated before age 10. CONCLUSIONS: Although there is an association of abnormal dark-adapted threshold and full-field electroretinogram at young ages in Usher patients, it appears that a small but important proportion of patients would not be detected by tests of retinal function alone. Thus, genetic testing is needed to secure a diagnosis of Usher syndrome.
Aminkhani A, Sharifi S, Hosseinzadeh P. Chemical Constituent, Antimicrobial Activity, and Synergistic Effect of the Stem, Leaf, and Flower Essential Oil of the Artemisia fragrans Willd. from Khoy. Chem Biodivers 2021;18(8):e2100241.Abstract
Artemisia fragrans is commonly used as a folk medicine as antispasmodic, anti-pyretic, anti-inflammatory, and abortifacient agents. The villagers use its pungent odor to repel rodents, mites, and pests, as well as its essential oil and smoke after burning to treat lung infections after uprooting the plant. Herein, we extracted the essential oils (EOs) of different parts of the plant and analyzed their chemical compositions and antibacterial activities. The chemical analysis led to the identification of 73, 59, and 57 compounds in the EOs of the stem, leaf, and flower, respectively. All of the EOs exhibited antibacterial activities against both G+ and G- bacteria. The EOs of the leaf and flower were more effective against tested bacteria, except B. anthracis and P. aeruginosa, compared to that of the stem. The binary combination of the EOs (stem and flower) or (stem and leaf) showed a synergistic effect. Statistical analysis indicated EOs of leaf and flower are more potent than that of the stem. These findings suggest the application of leaf and flower of the plant, which not only can prevent its uprooting but also ensure better therapeutic function.
Arroyo JG, Seto B, Yamada K, Zeng K, Minturn R, Lemire CA. Rapid reduction of macular edema due to retinal vein occlusion with low-dose normobaric hyperoxia. Graefes Arch Clin Exp Ophthalmol 2021;259(8):2113-2118.Abstract
PURPOSE: We investigated the effects of a relatively inexpensive, non-invasive, short-term treatment with low-dose normobaric hyperoxia (NBH) on macular edema in patients with retinal vein occlusion (RVO). METHODS: Participants with macular edema associated with RVO were treated with 5 LPM of NBH via facemask (40% fraction of inspired oxygen, FIO2) for 3 h. Patients with non-fovea involving edema who elected to be observed returned for a second treatment 1 month later to test reproducibility. RESULTS: A 3-h session of NBH (n = 45) resulted in decreased maximum macular thickness (MMT) (mean 7.10%, t34=9.63 P<.001) and central macular thickness (CMT) (mean 4.64%, t34=6.90, P<.001) when compared to untreated eyes with RVO measured over the same period of time (n = 12) or their healthy fellow eye (n = 34; MMT:t34=-9.60, P<.001;CMT: t34=-6.72, P<.001). Patients who had a second NBH treatment 1 month later experienced a recurrence of their edema, but demonstrated a similar significant reduction in MMT and CMT after the second NBH treatment. CONCLUSIONS: Three-hour treatment with 40% FIO2 NBH results in a significant reduction in MMT and CMT. This study supports an ischemic mechanism for macular edema associated with retinal vein occlusion. TRANSLATIONAL RELEVANCE: Short-term low-dose normobaric hyperoxia is a simple, inexpensive, and ubiquitous treatment that may provide an alternate or adjunctive approach to treating macular edema in patients who are resistant to or cannot afford anti-VEGF medications.
Avraham D, Jung J-H, Yitzhaky Y, Peli E. Retinal prosthetic vision simulation: temporal aspects. J Neural Eng 2021;18(4)Abstract
Objective. The perception of individuals fitted with retinal prostheses is not fully understood, although several retinal implants have been tested and commercialized. Realistic simulations of perception with retinal implants would be useful for future development and evaluation of such systems.Approach.We implemented a retinal prosthetic vision simulation, including temporal features, which have not been previously simulated. In particular, the simulation included temporal aspects such as persistence and perceptual fading of phosphenes and the electrode activation rate.Main results.The simulated phosphene persistence showed an effective reduction in flickering at low electrode activation rates. Although persistence has a positive effect on static scenes, it smears dynamic scenes. Perceptual fading following continuous stimulation affects prosthetic vision of both static and dynamic scenes by making them disappear completely or partially. However, we showed that perceptual fading of a static stimulus might be countered by head-scanning motions, which together with the persistence revealed the contours of the faded object. We also showed that changing the image polarity may improve simulated prosthetic vision in the presence of persistence and perceptual fading.Significance.Temporal aspects have important roles in prosthetic vision, as illustrated by the simulations. Considering these aspects may improve the future design, the training with, and evaluation of retinal prostheses.
Carreno-Galeano JT, Dohlman TH, Yin J, Dana R. Limbal Stem Cell Deficiency Associated With Herpes Keratitis. Cornea 2021;40(8):967-971.Abstract
PURPOSE: To describe the demographic features and clinical characteristics of patients with herpes keratitis (HK) and limbal stem cell deficiency (LSCD) and identify possible factors associated with development of LSCD after HK. METHODS: In this retrospective case-series study, records of patients with a clinical diagnosis of HK seen at Massachusetts Eye and Ear over a 5-year period were reviewed for evidence of LSCD. Patient demographics, medical history, treatment, and best-corrected visual acuities (BCVAs) were recorded. RESULTS: We identified 626 patients with HK. Fifty-seven had been diagnosed with LSCD (9.3%). Thirteen percent of patients with herpes zoster keratitis (N= 25) and 7% of patients with herpes simplex keratitis (N= 32) had LSCD (P = 0.01). Keratitis caused by herpes zoster virus [odds ratios (OR), 1.77; 95% confidence interval (CI), 0.97-3.19; P = 0.01], stromal involvement (OR, 2.28; 95% CI, 1.27-4.18; P = 0.02), and the use of topical antihypertensives (OR, 2.28; 95% CI, 1.27-4.18; P = 0.02) were found to be associated with a higher likelihood of developing LSCD. The final logarithm of the minimum angle of resolution (LogMAR) BCVA was significantly lower in patients with LSCD compared with those without LSCD with a mean BCVA of 1.34 ± 1.52 LogMar (∼20/200) as compared to 0.18 ± 0.54 LogMar (∼20/30 ± 20/60) in those patients without LSCD (P = 0.005). CONCLUSIONS: Our data suggest that HK may be a risk factor for development of LSCD. Patients with HK should be monitored for the development of LSCD to reduce the risk of chronic ocular surface morbidity.
Chang K, Enayati S, Cho K-S, Utheim TP, Chen DF. Non-invasive electrical stimulation as a potential treatment for retinal degenerative diseases. Neural Regen Res 2021;16(8):1558-1559.
Cox SM, Kheirkhah A, Aggarwal S, Abedi F, Cavalcanti BM, Cruzat A, Hamrah P. Alterations in corneal nerves in different subtypes of dry eye disease: An in vivo confocal microscopy study. Ocul Surf 2021;22:135-142.Abstract
PURPOSE: To evaluate corneal subbasal nerve alterations in evaporative and aqueous-deficient dry eye disease (DED) as compared to controls. METHODS: In this retrospective, cross-sectional, controlled study, eyes with a tear break-up time of less than 10 s were classified as DED. Those with an anesthetized Schirmer's strip of less than 5 mm were classified as aqueous-deficient DED. Three representative in vivo confocal microscopy images were graded for each subject for total, main, and branch nerve density and numbers. RESULTS: Compared to 42 healthy subjects (42 eyes), the 70 patients with DED (139 eyes) showed lower total (18,579.0 ± 687.7 μm/mm2 vs. 21,014.7 ± 706.5, p = 0.026) and main (7,718.9 ± 273.9 vs. 9,561.4 ± 369.8, p < 0.001) nerve density, as well as lower total (15.5 ± 0.7/frame vs. 20.5 ± 1.3, p = 0.001), main (3.0 ± 0.1 vs. 3.8 ± 0.2, p = 0.001) and branch (12.5 ± 0.7 vs. 16.5 ± 1.2, p = 0.004) nerve numbers. Compared to the evaporative DED group, the aqueous-deficient DED group showed reduced total nerve density (19,969.9 ± 830.7 vs. 15,942.2 ± 1,135.7, p = 0.006), branch nerve density (11,964.9 ± 749.8 vs. 8,765.9 ± 798.5, p = 0.006), total nerves number (16.9 ± 0.8/frame vs. 13.0 ± 1.2, p = 0.002), and branch nerve number (13.8 ± 0.8 vs. 10.2 ± 1.1, p = 0.002). CONCLUSIONS: Patients with DED demonstrate compromised corneal subbasal nerves, which is more pronounced in aqueous-deficient DED. This suggests a role for neurosensory abnormalities in the pathophysiology of DED.
Coyle S, Khan MN, Chemaly M, Callaghan B, Doyle C, Willoughby CE, Atkinson SD, Gregory-Ksander M, McGilligan V. Targeting the NLRP3 Inflammasome in Glaucoma. Biomolecules 2021;11(8)Abstract
Glaucoma is a group of optic neuropathies characterised by the degeneration of retinal ganglion cells, resulting in damage to the optic nerve head (ONH) and loss of vision in one or both eyes. Increased intraocular pressure (IOP) is one of the major aetiological risk factors in glaucoma, and is currently the only modifiable risk factor. However, 30-40% of glaucoma patients do not present with elevated IOP and still proceed to lose vision. The pathophysiology of glaucoma is therefore not completely understood, and there is a need for the development of IOP-independent neuroprotective therapies to preserve vision. Neuroinflammation has been shown to play a key role in glaucoma and, specifically, the NLRP3 inflammasome, a key driver of inflammation, has recently been implicated. The NLRP3 inflammasome is expressed in the eye and its activation is reported in pre-clinical studies of glaucoma. Activation of the NLRP3 inflammasome results in IL-1β processing. This pro inflammatory cytokine is elevated in the blood of glaucoma patients and is believed to drive neurotoxic inflammation, resulting in axon degeneration and the death of retinal ganglion cells (RGCs). This review discusses glaucoma as an inflammatory disease and evaluates targeting the NLRP3 inflammasome as a therapeutic strategy. A hypothetical mechanism for the action of the NLRP3 inflammasome in glaucoma is presented.
Doshi H, Solli E, Elze T, Pasquale LR, Wall M, Kupersmith MJ. Unsupervised Machine Learning Identifies Quantifiable Patterns of Visual Field Loss in Idiopathic Intracranial Hypertension. Transl Vis Sci Technol 2021;10(9):37.Abstract
Purpose: Archetypal analysis, a form of unsupervised machine learning, identifies archetypal patterns within a visual field (VF) dataset such that any VF is described as a weighted sum of its archetypes (ATs) and has been used to quantify VF defects in glaucoma. We applied archetypal analysis to VFs affected by nonglaucomatous optic neuropathy caused by idiopathic intracranial hypertension (IIH). Methods: We created an AT model from 2862 VFs prospectively collected from 330 eyes in the IIH Treatment Trial (IIHTT). We compared baseline IIH AT patterns with their descriptive VF classifications from the IIHTT. Results: The optimum IIH AT model yielded 14 ATs resembling VF patterns reported in the IIHTT. Baseline VFs contained four or fewer meaningful ATs in 147 (89%) of study eyes. AT2 (mild general VF depression pattern) demonstrated the greatest number of study eyes with meaningful AT weight at baseline (n = 114), followed by AT1 (n = 91). Other ATs captured patterns of blind spot enlargement, hemianopia, arcuate, nasal defects, and more nonspecific patterns of general VF depression. Of all ATs, AT1 (normal pattern) had the strongest correlation with mean deviation (r = 0.69, P < 0.001). For 65 of the 93 VFs with a dominant AT, this AT matched the expert classification. Conclusions: Archetypal analysis identifies quantifiable, archetypal VF defects that resemble those commonly seen in IIH. Translational Relevance: Archetypal analysis provides a quantitative, objective method of measuring and monitoring disease-specific regional VF defects in IIH.
Douglas VP, Douglas KA, Reinshagen KL, Chwalisz BK. Case 292: Lyme Neuroborreliosis. Radiology 2021;300(2):484-488.Abstract
History A 24-year-old right-handed woman presented to a neuro-ophthalmology clinic in Massachusetts in the summer with acute binocular diplopia when looking down and to the left, which started about 1 month earlier. Her medical history was notable for Raynaud syndrome, recurrent streptococcal pharyngitis, and an allergy to amoxicillin. Three days prior to developing diplopia, she presented to an outside emergency department due to fever, chills, and back pain. She received ciprofloxacin for presumed urinary tract infection based on urinalysis, which demonstrated few bacteria and was negative for leukocyte esterase, nitrites, and white blood cells. She then presented again to an outside emergency department for diplopia evaluation. Initial MRI and MR angiography of the brain at that time did not demonstrate any relevant findings, and the patient was referred to our department for neuro-ophthalmic evaluation, where she was seen 4 weeks later. Neuro-ophthalmic examination revealed 20/20 visual acuity in both eyes, and a right hypertropia in left gaze, downgaze and right head tilt, with right eye excyclotorsion. There were no ocular signs of myasthenia gravis or thyroid eye disease, nor did the patient report ocular or systemic symptoms. She denied recent travel. High-spatial-resolution MRI of the brain and orbit were performed.
Elhusseiny AM, Gise R, Mantagos IS. Trochleitis presenting with double vision in a patient with juvenile idiopathic arthritis. Orbit 2021;40(4):342-343.
Elhusseiny AM, Eleiwa TK, Yacoub MS, George J, ElSheikh RH, Haseeb A, Kwan J, Elsaadani IA, Abo Shanab SM, Solyman O, Saeed HN. Relationship between screen time and dry eye symptoms in pediatric population during the COVID-19 pandemic. Ocul Surf 2021;22:117-119.
Ferenchak K, Deitch I, Huckfeldt R. Antisense Oligonucleotide Therapy for Ophthalmic Conditions. Semin Ophthalmol 2021;36(5-6):452-457.Abstract
Antisense oligonucleotides (AON) are synthetic single-stranded fragments of nucleic acids that bind to a specific complementary messenger RNA (mRNA) sequence and change the final gene product. AON were initially approved for treating cytomegalovirus retinitis and have shown promise in treating Mendelian systemic disease. AON are currently being investigated as a treatment modality for many ophthalmic diseases, including inherited retinal disorders (IRD), inflammatory response and wound healing after glaucoma surgery, and macular degeneration. They provide a possible solution to gene therapy for IRD that are not candidates for adeno-associated virus (AAV) delivery. This chapter outlines the historical background of AON and reviews clinical applications and ongoing clinical trials.
Franco JJ, Reyes Luis JL, Rahim S, Greenstein S, Pineda R. Survival of the fittest: phacoemulsification outcomes in four corneal transplants by Dr Ramon Castroviejo. Br J Ophthalmol 2021;105(8):1076-1081.Abstract
AIM: To evaluate and report the outcomes following phacoemulsification on four eyes, 45 years or more after corneal transplantation. METHODS: A retrospective case series of four eyes in three patients (P1, P2, P3), undergoing phacoemulsification at least 45 years after corneal transplantation by Dr Ramon Castroviejo. Corneal graft survival outcome measures included central corneal thickness (CCT), best-corrected visual acuity (BCVA), corneal clarity and endothelial cell count (ECC). RESULTS: Phacoemulsification was successfully completed in all four cases with no instances of graft failure during the postoperative follow-up period, which ranged from 17 months to 76 months. At the conclusion of the follow-up period, all four grafts remained clear, and BCVA remained better than or similar to preoperative values. Long-term follow-up revealed no meaningful changes in CCT after phacoemulsification. All but one case experienced a decrease in ECC, with ECC values in the four cases ranging from 538 cells/mm2 to 1436 cells/mm2 at the conclusion of postoperative follow-up. CONCLUSION: Limited data have been published on the long-term survival of corneal grafts after intraocular surgery, especially for extremely 'mature' corneal transplants. This case series demonstrates that with appropriate preoperative, intraoperative and postoperative measures, successful phacoemulsification can be performed in these cases with excellent long-term results.
Gowrisankaran S, Shah AS, Roberts TL, Wiecek E, Chinn RN, Hawash KK, O'Brien MJ, Howell DR, Meehan WP, Raghuram A. Association between post-concussion symptoms and oculomotor deficits among adolescents. Brain Inj 2021;:1-11.Abstract
PURPOSE: To examine the association between Post-Concussion Symptom Scale (PCSS) scores, Convergence Insufficiency Symptom Survey (CISS) scores, and oculomotor deficits post-concussion. METHODS: Records of adolescent patients examined in a multidisciplinary concussion clinic between July 2014 and May 2019 were reviewed. PCSS and CISS scores, results of eye examination and oculomotor assessment, concussion history, and demographics were abstracted. RESULTS: One hundred and forty patient records (median age, 15.3 years; 52 males, presented 109 days (median) from their most recent concussion) met inclusion criteria. Mean total scores on PCSS and CISS were 46.67 ± 25.89 and 27.13 ± 13.22, respectively, and were moderately correlated with each other (r = 0.53, p < .001). Oculomotor deficits were observed in 123 (88%) patients. Step-wise linear regression identified increased PCSS total score to be significantly associated with decreased amplitude of accommodation (p < .001). Increased CISS total score was significantly associated with receded near point of convergence, developmental eye movement test error scores, and cause of concussion. CONCLUSION: High PCSS scores may indicate an accommodation deficit and thus prompt an oculomotor assessment in patients following a concussion. Using the CISS and a detailed oculomotor assessment may reveal underlying oculomotor deficits, which may benefit from treatment.
Halawa OA, Friedman DS, Roldan AM, Zebardast N. Changing trends in ocular trauma during the COVID-19 pandemic in the USA. Br J Ophthalmol 2021;Abstract
BACKGROUND/AIMS: The COVID-19 pandemic has been associated with a decline in emergency department (ED) presentations for trauma. The purpose of this study is to compare the estimated number and characteristics of eye injuries in 2020, the year of the COVID-19 pandemic, to those in 2011-2019. METHODS: A stratified probability sample of US ED-treated eye injuries was used to calculate the estimated annual number and incidence of these injuries in 2020, the year of the pandemic, and 2011-2019 (prepandemic years). Two-sample t-tests and Pearson χ2 were used to assess differences in demographics and injury characteristics. For multiple comparisons, Bonferroni correction was applied. RESULTS: The estimated number of ED-treated eye injuries per year was 152 957 (95% CI 132 637 to 176 153) in 2020 and 194 142 (95% CI 191 566 to 196 401) in 2011-2019. The annual incidence of ED-treated eye injuries was lower in 2020, at 46 per 100 000 population than in 2011-2019, at 62 per 100 000 per year (p<0.001). In 2020 vs 2011-2019, there was a higher incidence of ruptured globes (0.5 per 100 000 vs 0.3 per 100 000 per year, p<0.001), hyphemas (0.6 per 100 000 vs 0.4 per 100 000 per year, p<0.001), lacerations (1.0 per 100 000 in 2020 vs 0.8 per 100 000 per year, p<0.001) and orbital fractures (0.3 per 100 000 vs 0.03). CONCLUSION: The estimated incidence of eye injuries presenting to the ED was significantly lower in 2020 than in 2011-2019, but there was a higher estimated incidence of severe eye injuries. Changes in living and work environments due to the COVID-19 pandemic were likely associated with the differences in ocular trauma presentations observed in this study.
Huang X, Sun J, Majoor J, Vermeer KA, Lemij H, Elze T, Wang M, Boland MV, Pasquale LR, Mohammadzadeh V, Nouri-Mahdavi K, Johnson C, Yousefi S. Estimating the Severity of Visual Field Damage From Retinal Nerve Fiber Layer Thickness Measurements With Artificial Intelligence. Transl Vis Sci Technol 2021;10(9):16.Abstract
Purpose: The purpose of this study was to assess the accuracy of artificial neural networks (ANN) in estimating the severity of mean deviation (MD) from peripapillary retinal nerve fiber layer (RNFL) thickness measurements derived from optical coherence tomography (OCT). Methods: Models were trained using 1796 pairs of visual field and OCT measurements from 1796 eyes to estimate visual field MD from RNFL data. Multivariable linear regression, random forest regressor, support vector regressor, and 1D convolutional neural network (CNN) models with sectoral RNFL thickness measurements were examined. Three independent subsets consisting of 698, 256, and 691 pairs of visual field and OCT measurements were used to validate the models. Estimation errors were visualized to assess model performance subjectively. Mean absolute error (MAE), root mean square error (RMSE), median absolute error, Pearson correlation, and R-squared metrics were used to assess model performance objectively. Results: The MAE and RMSE of the ANN model based on the testing dataset were 4.0 dB (95% confidence interval = 3.8-4.2) and 5.2 dB (95% confidence interval = 5.1-5.4), respectively. The ranges of MAE and RMSE of the ANN model on independent datasets were 3.3-5.9 dB and 4.4-8.4 dB, respectively. Conclusions: The proposed ANN model estimated MD from RNFL measurements better than multivariable linear regression model, random forest, support vector regressor, and 1-D CNN models. The model was generalizable to independent data from different centers and varying races. Translational Relevance: Successful development of ANN models may assist clinicians in assessing visual function in glaucoma based on objective OCT measures with less dependence on subjective visual field tests.
Jowett N, Pineda R. Seeing through the evidence for corneal neurotization. Curr Opin Otolaryngol Head Neck Surg 2021;29(4):252-258.Abstract
PURPOSE OF REVIEW: Trigeminal anesthesia causes neurotrophic keratopathy, which may yield facial disfigurement and corneal blindness. RECENT FINDINGS: We summarize approaches and evidence for corneal neurotization. SUMMARY: Regional sensory nerve transfer appears safe and effective for therapeutic management of neurotrophic keratopathy. Prospective randomized clinical trials are necessary to confirm the utility of corneal neurotization.
Jowett N, Pineda R. Corneal and Facial Sensory Neurotization in Trigeminal Anesthesia. Facial Plast Surg Clin North Am 2021;29(3):459-470.Abstract
Trigeminal anesthesia may yield blindness and facial disfigurement, secondary to neurotrophic keratopathy and trigeminal trophic syndrome. This article summarizes contemporary medical and emerging surgical approaches for the therapeutic management of this rare and devastating disease state.
Konstantinou EK, Shaikh N, Ramsey DJ. Birt-Hogg-Dubé syndrome associated with chorioretinopathy and nyctalopia: a case report and review of the literature. Ophthalmic Genet 2021;:1-7.Abstract
PURPOSE: To report a rare case of Birt-Hogg-Dubé Syndrome (BHD) with progressive chorioretinopathy. METHODS: Case report. RESULTS: A 55-year-old woman presented with longstanding nyctalopia attributed to a congenital retinal dystrophy, but no prior genetic testing. Her posterior pole examination demonstrated retinal pigment epithelium (RPE) mottling with extensive macular drusen and paracentral chorioretinal atrophy, consistent with a fleck retinopathy. Her past medical history was remarkable for nephrectomy for unilateral renal malignancy, parotid tumors and thyroid nodules. Dark adaptation time was prolonged, and electroretinography (ERG) revealed abnormal waveforms with depressed amplitudes. Genetic testing confirmed a deletion mutation in the folliculin (FLCN) gene and was negative for other relevant mutations, including EFEMP1 responsible for autosomal dominant macular and peripapillary drusen in Doyne honeycomb retinal dystrophy and TIMP3 responsible for Sorsby Fundus Dystrophy. CONCLUSION: BHD is a rare autosomal-dominant disorder with multi-systemic clinical manifestations caused by a mutation in the FLCN gene. Affected individuals are prone to renal and pulmonary cysts, renal cancer, and fibrofolliculomas. Reports on ocular manifestations of BHD include eyelid fibrofolliculomas, flecked chorioretinopathy, choroidal melanoma, choroidal melanoma with sector melanocytosis, and retinal pigment epithelial micro-detachments. In this case of BHD, we note a fleck retinopathy with bilateral chorioretinal atrophy, displaying a phenotype of extensive chorioretinopathy associated with impaired dark adaptation and ERG abnormalities. ABBREVIATIONS: BHD: Birt-Hogg-Dubé syndrome; FLCN: Folliculin. RPE: retinal pigment epithelium; OD: Oculus dexter (right eye); OS: Oculus sinister (left eye). OU: Oculus uterque (both eyes); ERG: electroretinogram; mfERG: multifocal electroretinography. ffERG: full-field electroretinography; FAF: fundus autofluorescence; OCT: optical coherence tomography; FA: fluorescein angiography; DA: dark-adapted; LA: light-adapted; mTOR: mammalian target of rapamycin; EFEMP1: epithelial growth factor-containing fibulin-like extracellular matrix protein 1; VPS13B: Vacuolar Protein Sorting 13 Homolog B; AGBL5: AATP/GTP-Binding Protein Like 5; ALMS1: Alstrom Syndrome 1; COL1BA1: Collagen Type I Beta, Alpha Chain 1; PDE6A: Rod Phosphodiesterase 6-alpha; USH2A: Usherin 2a; VCAN: Versican; RP: Retinitis pigmentosa; AR: Autosomal recessive.