Validation of retinal oximetry vessel selection using fluorescein angiography in patients with optic disc drusen.

Retinal oximetry could provide insights into the pathophysiology of optic nerve disease, including optic disc drusen (ODD). Vessel selection for oximetry analysis is based on morphological characteristics of arterioles and venules and supported by an overlay of estimated blood oxygen saturations. The purpose of this cross-sectional study was to determine the validity of this vessel selection procedure by comparing it with vessel selection supported by video fluorescein angiography (FA). The study included 36 eyes of 36 patients with ODD who underwent retinal oximetry (Oxymap retinal oximeter T1) followed by FA (Heidelberg Spectralis). Two trained graders selected vessel segments in a pre-defined measurement area around the optic disc. One of these graders additionally performed the vessel segment selection with the support of FA images. When performed by the same grader, FA-supported and non-FA-supported vessel selection did not lead to significant differences in total vessel segment length, estimated oxygen saturations or vessel diameters (all p > 0.05). Inter-grader differences were found for arterial and venous segment lengths and arterial saturation (p < 0.05). A similar tendency was found for the arteriovenous saturation difference (p = 0.10). In conclusion, identifying vessel segments for retinal oximetry analysis based on vessel morphology and supported by a color-coded saturation overlay appears to be a valid method without the need for invasive angiography. A numerically small inter-grader variation may influence oximetry results. Further studies of retinal oximetry in ODD are warranted.

Prevalence of optic disc drusen: A systematic review, meta-analysis and forecasting study.

Optic disc drusen (ODD) are calcium-containing deposits in the optic nerve head, capable of causing visual field defects and sudden visual loss. The underlying pathophysiology remains inadequately understood and treatment options are missing. In this paper, we systematically reviewed prevalence studies of ODD in non-selected populations to provide an overview of its prevalence, conducted meta-analyses to determine modality-specific prevalence estimates and performed a forecasting study to estimate current and future global population number of individuals with ODD. We searched 11 literature databases on 25 October 2022 for prevalence studies of ODD in non-selected populations. Eight eligible studies provided data from a total of 27 463 individuals. Prevalence estimates were stratified according to diagnostic modalities: ophthalmoscopy 0.37% (95% CI: 0.10-0.95%), fundus photography 0.12% (95% CI: 0.03-0.24%), spectral domain optical coherence tomography with enhanced depth imaging 2.21% (95% CI: 1.25-3.42%) and histopathology 1.82% (95% CI: 1.32-2.38%). Using histopathology-based summary prevalence estimate, we forecast 145 million individuals with ODD currently, a number expected to increase further due to world population growth. These numbers underscore the importance of including ODD in health education and highlight the necessity of continuing research in ODD.

Optic Disc Drusen Prevalence in Patients With Retinitis Pigmentosa: A Cross-Sectional Study.

BACKGROUND: Studies of patients with retinitis pigmentosa (RP) have reported an increased prevalence of optic disc drusen (ODD) compared with the ODD prevalence in the general population. The diagnostic gold standard method for identifying ODD is enhanced depth imaging optical coherence tomography (EDI-OCT), but this modality has not previously been used systematically for identifying ODD in patients with RP. This study aimed to estimate the prevalence of ODD in patients with RP using EDI-OCT. METHODS: In this cross-sectional study, 40 patients with clinically diagnosed RP aged 18 years or older were included. All patients underwent an ophthalmic examination, including kinetic perimetry, EDI-OCT of the optic nerve head, and fundus photography. Genetic testing with a next-generation sequencing panel of retinal dystrophy genes was performed on the RP patients without a prior genetic diagnosis. RESULTS: Twelve patients (30.0%) had at least one ODD. Six patients had bilateral ODD. No significant differences between patients with and without ODD were found according to age, refraction, best-corrected visual acuity, Bruch membrane opening, or visual field. The genetic variation causing RP was found in 11 of 12 cases in the ODD group and in 17 of 28 cases in the group without ODD. CONCLUSIONS: We found the prevalence of ODD in patients with RP to be 30.0%. This is 15 times higher than in the general population and much higher than previously estimated in most studies, potentially indicating that the 2 conditions might be pathogenically related.

Artificial Intelligence-Based ChatGPT Responses for Patient Questions on Optic Disc Drusen.

INTRODUCTION: Optic disc drusen (ODD) are acellular deposits in the optic nerve head, which are most often benign and asymptomatic. Patients may develop visual field defects and be at increased risk of ischemic co-morbidities. As ODD can be difficult to distinguish from papilledema, patients are at risk of unnecessary clinical workups. Patient information is a key aspect of ODD management. In this study, we explored the accuracy of ChatGPT responses for typical patient questions on ODD. METHODS: Two content experts reached consensus on 20 typical patient questions. We retrieved five separate responses for each question from ChatGPT, totaling 100 responses. Each response was evaluated on a 5-point Likert-scale on accuracy by each content expert in an individual fashion. RESULTS: The two experts were in fair/substantial agreement in the evaluation of responses (Cronbach's alpha: 0.64). Of the 100 responses, 17 were relevant and without any inaccuracies, 78 were relevant and with inaccuracies not being harmful, and five were relevant and with inaccuracies potentially harmful. The lowest accuracy scores were obtained for questions dealing with treatment and prognosis. CONCLUSIONS: ChatGPT often provides relevant answers for patient questions on ODD, but inaccuracies become potentially harmful when questions deal with treatment and prognosis.

Peripapillary Hyperreflective Ovoid Mass-like Structures (PHOMS) in Children: The Copenhagen Child Cohort 2000 Eye Study.

PURPOSE: To determine the prevalence of peripapillary hyperreflective ovoid mass-like structures (PHOMS) in a population-based child cohort and to study their association with other optic nerve head features and myopia. DESIGN: Observational, population-based cohort study of 1407 children aged 11-12 years. METHODS: Optical coherence tomography scans of optic nerve heads were graded for PHOMS, disc tilt, prelaminar hyperreflective lines, and scleral canal diameter and investigated for associated prenatal and ocular parameters. Children with optic disc drusen or optic disc edema were excluded. RESULTS: PHOMS were found in 8.9% of children. The location of PHOMS was predominantly in the superonasal section of the optic disc. Myopia and optic nerve head tilt were more common in children with PHOMS than in children without PHOMS (P < .001 and P < .001, respectively). Prelaminar hyperreflective lines were found in 17.9% of children with PHOMS compared to 7.3% of children without PHOMS (P < .001). Prelaminar hyperreflective lines with and without PHOMS were associated with a shorter axial length of the eye (P < .001). There were no prenatal factors associated with PHOMS. Prelaminar hyperreflective lines were associated with higher birth weight and continued maternal smoking during pregnancy (P = .01 and P = .02, respectively). CONCLUSIONS: PHOMS had a prevalence of 8.9% in healthy children without optic disc drusen or optic disc edema and was associated with increasing myopic refraction and the presence of a tilted optic nerve head and prelaminar hyperreflective lines. Given the high prevalence of PHOMS, they should not unreservedly be taken as evidence of optic neuropathy.

Peripapillary Vessel Density in Relation to Optic Disc Drusen: A Multimodal Optical Coherence Tomography Study.

BACKGROUND: Optic disc drusen (ODD) are acellular calcified deposits within the optic nerve head known to cause visual field defects. An emerging gold standard for the diagnosis of ODD is enhanced depth imaging optical coherence tomography (EDI-OCT). The presence of ODD affects the adjacent peripapillary vasculature, which can be visualized using OCT angiography (OCTA). This study investigates the association between peripapillary vessel density and anatomical ODD location and volume using a newly developed method of multimodal OCT. METHODS: A case-control study with 16 patients diagnosed with ODD in the period 2008-2017 and 24 healthy controls. All patients and controls had EDI-OCT, OCTA, and demographic data collected. Using EDI-OCT and the medical imaging segmentation tool ITK-SNAP, 3-dimensional (3D) visualization of ODD in patients were created. ODD 3D visualization and corresponding OCTA scans were superimposed, making it possible to correlate ODD volume to the peripapillary vessel density in the corresponding modified Garway-Heath segments of the optic disc. RESULTS: We found that mean peripapillary vessel density across all modified Garway-Heath segments were lower in ODD patients compared with controls with significant reduction of peripapillary vessel density in the superior segment ( P = 0.03) and globally ( P = 0.05). A significant inverse proportionality between ODD volume and peripapillary vessel density in the corresponding segment was seen ( P = 0.002). CONCLUSIONS: We found a reduced peripapillary vessel density in regions with close anatomical proximity to ODD and inverse proportionality between ODD volume and peripapillary vessel density.

Comparison of Spectral-Domain OCT versus Swept-Source OCT for the Detection of Deep Optic Disc Drusen.

Deep optic disc drusen (ODD) are located below Bruch's membrane opening (BMO) and may go undetected due to the challenges in imaging them. The purpose of this study is a head-to-head comparison of currently widely used imaging technologies: swept-source optical coherence tomography (SS-OCT; DRI OCT-1 Triton, Topcon) and enhanced depth imaging spectral-domain optical coherence tomography (EDI SD-OCT; Spectralis OCT, Heidelberg Engineering) for the detection of deep ODD and associated imaging features. The eyes included in this study had undergone high-resolution imaging via both EDI SD-OCT and SS-OCT volume scans, which showed at least one deep ODD or a hyperreflective line (HL). Grading was performed by three graders in a masked fashion. The study findings are based on 46 B-scan stacks of 23 eyes including a total of 7981 scans. For scan images with ODD located above or below the level of BMO, no significant difference was found between the two modalities compared in this study. However, for HLs and other features, EDI SD-OCT scan images had better visualization and less artifacts. Although SS-OCT offers deep tissue visualization, it did not appear to offer any advantage in ODD detection over a dense volume scan via EDI SD-OCT with B-scan averaging.

Volumetric Measurement of Peripapillary Hyperreflective Ovoid Masslike Structures in Patients with Optic Disc Drusen.

Purpose: To develop a method to determine the volume of peripapillary hyperreflective ovoid masslike structures (PHOMS) and to examine the correlation between PHOMS and anatomic optic nerve head characteristics in a large cohort of patients with optic disc drusen (ODD). Design: Retrospective, observational study of patients with ODD. Participants: Patients with ODD seen in a 3-year period. Methods: We determined the prevalence of PHOMS. We then developed a method to calculate the volume of PHOMS and measured this in all patients where radial scans on OCT were available. We analyzed the correlation between PHOMS volume and patient age, size of Bruch's membrane opening (BMO), ODD visibility, and anatomic location of ODD in the optic nerve. Main Outcome Measures: Prevalence and characteristics of PHOMS in patients with ODD. Results: In 247 (77%) eyes with ODD, PHOMS were found. Among these, 80% were in the first decade of life, 87% were in the second decade, 89% were in the third decade, 85% were in the fourth decade, 74% were in the fifth decade, 73% were in the sixth decade, 58% were in the seventh decade, 40% were in the eighth decade, and 0% were in the ninth decade. The ophthalmoscopic visibility of ODD increased with age. The volume of PHOMS decreased with age, but with no correlation to the size of BMO. The median volume of PHOMS was 0.27 mm3 (interquartile range [IQR], 0.13-0.49 mm3). Predominantly, PHOMS were observed in the nasal peripapillary area (87.5% nasal, 78.5% superior, 67% inferior, and 63.5% temporal). Conclusions: In patients with ODD, PHOMS are seen frequently, with the highest prevalence in younger individuals. The volume of PHOMS decreases with age, and PHOMS are seen more frequently in patients with superficial ODD.

Analysis of Systemic Risk Factors and Post-Insult Visual Development in a Danish Cohort of Patients with Nonarteritic Anterior Ischemic Optic Neuropathy.

Purpose: Nonarteritic anterior ischemic optic neuropathy (NAION) is associated with vascular as well as anatomical risk factors. Following the insult, the visual development varies from minor to severe deterioration. The aim of this study was to examine possible prognostic systemic risk factors and their eventual impact on post-insult visual development in NAION patients. Methods: A retrospective chart review of all NAION patients (18-79 years at time of diagnosis) seen a minimum of two times in a tertiary eye department during a 10-year period in regard to systemic diseases, medication, lifestyle factors and ophthalmic examination was performed. Visual outcome was assessed according to the development of best corrected visual acuity (BCVA) and visual field from initial to final visit. Results: There were 163 eligible patients. A greater proportion of the patients in the total cohort were over 50 years of age (79.8%) and men (66.3%). In total, 59.5% of the patients had a stable BCVA, while 25.8% experienced improvement, and 14.7% had deterioration. Seventy-two percent of the patients had a stable visual field, while 14% had improvement, and 14% had deterioration. No association between visual outcome and clinical characteristics, medication or systemic risk factors were identified. Conclusion: We did not find any association between patient characteristics and systemic risk factors at time of diagnosis and visual development post-insult. This could suggest that the optic nerve head anatomy plays a larger role for visual outcome than previously estimated.

Optic Nerve Head Anatomy and Vascular Risk Factors in Patients With Optic Disc Drusen Associated Anterior Ischemic Optic Neuropathy.

PURPOSE: Optic disc drusen (ODD) is an anatomical risk factor for nonarteritic anterior ischemic optic neuropathy (NA-AION). This study aimed to investigate the anatomical and vascular risk factors of patients with ODD-AION (ODD-associated NA-AION) and compare them with similar data from patients with nODD-AION (NA-AION without ODD). DESIGN: Case-control study. METHODS: Thirty-four ODD-AION and 34 nODD-AION patients who had all been systematically optical coherence tomography scanned using a standardized ODD scanning protocol were retrospectively analyzed and compared regarding demographics, vascular risk factors, clinical characteristics, and specific optic nerve head anatomical characteristics. RESULTS: In patients with ODD-AION, the ODD were predominantly deeply located (82%) but with no significant difference in size (52% large, 48% small). When compared with nODD-AION patients, ODD-AION patients were significantly younger at the time of diagnosis (P = .012) and had fewer vascular risk factors (P = .015). The ODD-AION patients had significantly more peripapillary hyperreflective ovoid mass-like structures (PHOMS) (P < .001) and prelaminar hyperreflective lines (P < .001) as well as smaller Bruch's membrane opening diameters (P = .017) compared with nODD-AION patients. No significant differences were found between ODD-AION and nODD-AION patients regarding visual acuity, refraction, lamina cribrosa position, ganglion cell layer volume, or retinal nerve fiber layer thickness. CONCLUSION: In ODD-AION, location of the ODD within the optic nerve head is important, while the size of the ODD is not. The ODD-AION and nODD-AION patients presented with distinctly different vascular risk factors and anatomical characteristics, establishing ODD and potentially also PHOMS as independent risk factors for developing NA-AION.

Cardiac arrhythmias six months following traumatic spinal cord injury.

OBJECTIVE: To investigate the incidence of cardiac arrhythmias at six months following traumatic spinal cord injury (SCI) and to compare the prevalence of arrhythmias between participants with cervical and thoracic SCI. DESIGN: A prospective observational study using continuous twenty-four-hour Holter monitoring. SETTING: Inpatient rehabilitation unit of a university research hospital and patient home setting. PARTICIPANTS: Fifty-five participants with acute traumatic SCI were prospectively included. For each participant, the SCI was characterized according to the International Standards for Neurological Classification of SCI by the neurological level and severity according to the American Spinal Injury Association Impairment Scale. OUTCOME MEASURES: Comparisons between demographic characteristics and arrhythmogenic occurrences as early as possible after SCI (4 ± 2 days) followed by 1, 2, 3, 4 weeks and 6 month time points of Holter monitoring. RESULTS: Bradycardia (heart rate [HR] <50 bpm) was present in 29% and 33% of the participants with cervical (C1-C8) and thoracic (T1-T12) SCI six months after SCI, respectively. The differences in episodes of bradycardia between the two groups were not significant (P < 0.54). The mean maximum HR increased significantly from 4 weeks to 6 months post-SCI (P < 0.001), however mean minimum and maximum HR were not significantly different between the groups at the six-month time point. There were no differences in many arrhythmias between recording periods or between groups at six months. CONCLUSIONS: At the six-month timepoint following traumatic SCI, there were no significant differences in occurrences of arrhythmias between participants with cervical and thoracic SCI compared to the findings observed in the first month following SCI.

OCT Based Interpretation of the Optic Nerve Head Anatomy and Prevalence of Optic Disc Drusen in Patients with Idiopathic Intracranial Hypertension (IIH).

We aimed to systematically examine the optic nerve head anatomy in patients with idiopathic intracranial hypertension (IIH) using a standardized optical coherence tomography (OCT) protocol. The study retrospectively included 32 patients diagnosed from 2014 to 2021 with IIH. Using OCT, in accordance with a standardized scanning protocol for patients with optic disc drusen, the presence of optic disc drusen, prelaminar hyperreflective lines, peripapillary hyperreflective ovoid mass-like structures, the retinal nerve fiber layer thickness, and macular ganglion cell layer volume was obtained. Optic disc drusen were found in 3.1%, hyperreflective lines in 31.3%, and peripapillary hyperreflective ovoid mass-like structures in 81.3% of all IIH patients at least three months after the time of diagnosis. We found no significant differences in retinal nerve fiber layer thickness or macular ganglion cell layer volume in patients with hyperreflective lines or PHOMS respectively compared to patients without hyperreflective lines (p = 0.1285 and p = 0.1835). In conclusion, the prevalence of optic disc drusen in IIH patients is similar to the reported prevalence in the general population. The high prevalence of hyperreflective lines and peripapillary hyperreflective ovoid mass-like structures in IIH patients suggest these structures be a result of crowding in the optic nerve head caused by papilledema.

Optic Nerve Head Blood Flow Analysis in Patients with Optic Disc Drusen Using Laser Speckle Flowgraphy.

Visual field defects are common in patients with optic disc drusen (ODD). Our aim was to examine whether reduced optic nerve head (ONH) microcirculation is related to visual field defects in ODD patients. Vascular and tissue area mean blur rate (MBRV and MBRT), measured using laser speckle flowgraphy (LSFG), was significantly lower in the 32 included ODD eyes when compared with 40 healthy eyes (p <.05). There was a moderate correlation between the difference in MBRT and the perimetric mean defect (R2 = 0.53) in ODD patients. These findings demonstrate the utility of LSFG in examining ONH blood flow in ODD patients.

OCT based interpretation of the optic nerve head anatomy in young adults with retinal vascular occlusions and ischemic optic neuropathy.

PURPOSE: To examine optic nerve head (ONH) anatomy in young adults with central retinal vein occlusion (CRVO), branch retinal vein occlusion (BRVO), central retinal artery occlusion (CRAO), branch retinal artery occlusion (BRAO) or nonarteritic anterior ischemic optic neuropathy (NA-AION) in order to look for associated, potentially predisposing anomalies. METHODS: Cross-sectional study including 54 patients (ages 16-50 years) diagnosed from 2009 to 2018 with CRVO, BRVO, CRAO, BRAO, or NA-AION. Using Optical Coherence Tomography the presence of optic disc drusen (ODD), prelaminar hyperreflective lines and peripapillary hyperreflective ovoid mass-like structures (PHOMS), and determination of scleral canal size, retinal nerve fiber layer thickness (RNFLT) and macular ganglion cell layer thickness (GCLT) was obtained. Data for retinal vascular occlusion patients were grouped and analyzed together. RESULTS: ODD were found in 13% of all patients, 2% of retinal vascular occlusion patients and 67% of NA-AION patients (p < 0.0001). Prelaminar hyperreflective lines were found in 35% of all patients, 24% of retinal vascular occlusion patients and 89% of NA-AION patients (p = 0.0005). PHOMS were found in 20% of all patients, 13% of retinal vascular occlusion patients and 56% of NA-AION patients (p = 0.012). RNFLT was decreased in ODD patients compared to patients without ODD (p = 0.01). Scleral canal diameter and GCLT was not correlated with ODD, prelaminar hyperreflective lines or PHOMS. CONCLUSION: ODD, prelaminar hyperreflective lines and PHOMS were more frequent in NA-AION patients compared to retinal vascular occlusion patients. The prevalence of ODD in retinal vascular occlusion patients was similar to the reported prevalence in the general population.

Prevalence of Optic Disc Drusen in Young Patients With Nonarteritic Anterior Ischemic Optic Neuropathy: A 10-Year Retrospective Study.

BACKGROUND: Nonarteritic anterior ischemic optic neuropathy (NAION) in young patients (age ≤50) accounts for a minority of all cases of NAION and is more highly associated with crowding of the optic nerves and bilateral involvement than NAION in older patients. Optic disc drusen (ODD) are likewise associated with crowded optic nerves and are located in the prelaminar optic nerve head where they could contribute to NAION pathogenesis. The purpose of this study was to determine the prevalence of ODD in the eyes of young NAION patients using modern imaging methods and to compare it to the baseline 1.8%-2.0% prevalence of ODD in the general population. METHODS: In this retrospective study, all young NAION patients (ages 18-50 years, inclusive) seen in 2 tertiary care neuro-ophthalmology clinics (in London, Canada and Copenhagen, Denmark) in the ten-year interval between April 1, 2009, and March 31, 2019, were identified and their medical charts reviewed. Patients were included in the study if ODD were diagnosed by any method (including ophthalmoscopy, ultrasound [US], fundus autofluorescence [FAF], computed tomography [CT], or any optical coherence tomography [OCT] method), or if ODD were excluded by enhanced-depth imaging OCT (EDI-OCT) using the ODD Studies (ODDS) Consortium protocol. The presence or absence of ODD was recorded for each eye. RESULTS: There were 37 eligible patients (74 eyes). Mean age of NAION onset was 38.5 ± 10.0 years, and 23 patients (62%) were men. Patients had undergone the following methods of ODD detection: ophthalmoscopy (37 patients), EDI-OCT (36 patients), FAF (31 patients), US (9 patients), and CT orbits (8 patients). We found a prevalence of ODD of 56.7% in NAION-affected patients and 53.3% in NAION-affected eyes. Only 35.9% of ODD were visible on ophthalmoscopy. Twenty of 21 ODD patients (95.2%) had bilateral ODD. Age of onset and sex did not differ significantly between the ODD-positive group and the ODD-negative group. EDI-OCT outperformed any combination of ophthalmoscopy, US, FAF, and CT at detecting ODD. CONCLUSION: ODD were found with much higher prevalence in young patients with NAION than in the general population and were usually bilateral and buried. ODD may contribute to NAION pathogenesis by exacerbating an underlying compartment syndrome in the crowded "disc at risk." EDI-OCT may be the best imaging modality for ODD detection in future studies.

Determination of peripapillary vessel density in optic disc drusen using EDI-OCT and OCT angiography.

Optical coherence tomography angiography (OCTA) is a rapidly developing technique which generates angiographic images non-invasively. This study proposes a method to determine the vessel density in OCTA scans in general and especially the local peripapillary vessel density. The method produces vessel density heatmaps that contain information about the local vessel density. We apply the method in a small study to demonstrate its applicability and its potential to investigate the influence of local conditions on the vessel density. In the study, we combine information from enhanced depth imaging optical coherence tomography (EDI-OCT) about the location of optic disc drusen (ODD) with information from OCTA about the vessel density. We see a reduction in local peripapillary vessel density in peripapillary sections with a large volume of ODD.

Young Adults With Anterior Ischemic Optic Neuropathy: A Multicenter Optic Disc Drusen Study.

PURPOSE: Optic disc drusen (ODD), present in 2% of the general population, have occasionally been reported in patients with nonarteritic anterior ischemic optic neuropathy (NA-AION). The purpose of this study was to examine the prevalence of ODD in young patients with NA-AION. DESIGN: Retrospective, cross-sectional multicenter study. METHODS: All patients with NA-AION 50 years old or younger, seen in neuro-ophthalmology clinics of the international ODDS (Optic Disc Drusen Studies) Consortium between April 1, 2017, and March 31, 2019, were identified. Patients were included if ODD were diagnosed by any method, or if ODD were excluded by enhanced-depth imaging optical coherence tomography (EDI-OCT) using ODDS Consortium guidelines. NA-AION eyes with ODD were termed "ODD-AION"; those without were termed "NODD-AION". RESULTS: A total of 65 patients (127 eyes) with NA-AION were included (mean 41 years old). Of the 74 eyes with NA-AION, 51% had ODD-AION, whereas 43% of fellow eyes without NA-AION had ODD (P = .36). No significant differences were found between ODD-AION and NODD-AION eyes in terms of Snellen best-corrected VA or perimetric mean deviation. According to EDI-OCT results, 28% of eyes with NODD-AION had peripapillary hyperreflective ovoid mass-like structures (PHOMS); 7% had hyperreflective lines, whereas 54% with ODD-AION had PHOMS; and 66% had hyperreflective lines (P = .006 and P < .001, respectively). CONCLUSIONS: Most of these young NA-AION patients had ODD. This indicates that ODD may be an independent risk factor for the development of NA-AION, at least in younger patients. This study suggests ODD-AION be recognized as a novel diagnosis.