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.

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.

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.

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.

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.

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.

Optic Disc Drusen Associated Anterior Ischemic Optic Neuropathy: Prevalence of Comorbidities and Vascular Risk Factors.

BACKGROUND: Nonarteritic anterior ischemic optic neuropathy (NA-AION) associated with optic disc drusen (ODD) is termed ODD-AION, where NA-AION with no evidence of ODD is simply termed NA-AION. Patients with ODD-AION have been found to be younger than those with NA-AION but with similar vascular risk factors. This study compares the known risk factors for NA-AION between a group with ODD-AION and a similarly aged group with NA-AION. METHODS: A case-control study of 13 patients with ODD-AION and 14 patients with NA-AION diagnosed in the period 2008-2017. All patients underwent an interview designed to evaluate history of vascular risk factors and comorbidities and re-examination including enhanced depth imaging optical coherence tomography to confirm the presence or absence of ODD. RESULTS: No significant differences were found in demographic or clinical characteristics between the ODD-AION and the NA-AION group. Significantly more ODD-AION patients than NA-AION patients had no vascular risk factors (smoking, arterial hypertension, diabetes mellitus, and dyslipidemia) present (P = 0.047). Significantly fewer patients in the ODD-AION group were diagnosed with arterial hypertension or dyslipidemia than in the NA-AION group. CONCLUSIONS: In this cross-sectional study, the ODD-AION patients more often had no vascular risk factors as compared to NA-AION patients, which supports the hypothesis that ODD are an independent risk factor for AION.

Progression Over 5 Years of Prelaminar Hyperreflective Lines to Optic Disc Drusen in the Copenhagen Child Cohort 2000 Eye Study.

BACKGROUND: The purpose of the study was to examine 5-year changes in eyes with optic disc drusen at baseline on optical coherence tomography (OCT) scans and the relation of incident drusen to hyperreflective prelaminar lines. METHODS: The study included children who presented at baseline, when participants were aged 11-12 years, and again 5 years later. Grading for optic disc drusen was made in all. Grading for prelaminar lines was made in all children at follow-up and in eyes with optic disc drusen at baseline. Analyses included associations with scleral canal diameter at baseline in all children with optic disc drusen and a nested control group of 115 children without optic disc drusen. Data are reported as the number of children having at least one drusen or at least one hyperreflective line per person. RESULTS: The analysis included 724 children who attended both rounds of the study. Of these, 11 (1.5%) had optic disc drusen at baseline. Five additional children had developed optic disc drusen at follow-up, whereas optic disc drusen had disappeared in none, so that 16 (2.2%) children had optic disc drusen in one or both eyes at follow-up. Children with optic disc drusen at the 5-year follow-up had had a mean scleral canal diameter of 1,364 µm (interquartile range [IQR] 81 µm), compared with 1,457 µm (IQR 197) µm in 115 nested controls without optic disc drusen (P < 0.001). Optic disc drusen at follow-up were associated with more hypermetropic refraction. All children who had optic disc drusen at follow-up also had prelaminar hyperreflective lines. In addition, such lines were found at follow-up in 24 of the remaining 708 children without optic disc drusen (P < 0.001). Prelaminar hyperreflective lines with or without optic disc drusen were associated with a narrower scleral canal (diameter 1,364 µm, IQR 119 µm) compared with absence of prelaminar lines (1,486 µm, IQR 206 µm; P < 0.0001). CONCLUSION: This study provides the first evidence from a prospective study that small optic discs and prelaminar hyperreflective lines on OCT are risk factors for the development of optic disc drusen. The association between prelaminar hyperreflective lines, hypermetropia, and a narrow scleral canal supports that a crowded disc is an essential predisposing factor for the development of optic disc drusen.

The Angioarchitecture of the Optic Nerve Head in Patients with Optic Disc Drusen.

The aim was to analyse the optic disc angioarchitecture in optic disc drusen (ODD) patients using computer-based fundus analysis in a case-control study. Compared with controls the ODD group had a significantly more centralised central retinal artery (CRA) emergence (p < 0.001) and primary CRA branching (p = 0.008), a higher number of CRA bifurcations (p = 0.02), a larger vertical optic disc diameter (p = 0.02) and a smaller cup/disc ratio (p < 0.001). The CRA emergence was largely within the nasal zone for both groups. The distinctive angioarchitecture of the optic disc in ODD patients can play a role in understanding the pathogenic cause of ODD.

Multirater Validation of Peripapillary Hyperreflective Ovoid Mass-like Structures (PHOMS).

Peripapillary hyperreflective ovoid mass-like structures (PHOMS) are a new retinal optical coherence tomography (OCT) finding. The Optic Disc Drusen Studies Consortium had made recommendations to distinguish PHOMS from true optic disc drusen (ODD) in 2018. While publications on PHOMS have increased since then, the accuracy of the definition of PHOMS and reliability of detection is unknown. In this multi-rater study, we demonstrate that the 2018 definition of PHOMS resulted in a poor multi-rater kappa of 0.356. We performed a Delphi consensus process to develop a consistent and refined definition of PHOMS with clear principles around the nature of PHOMS and how they differ from normal anatomy. Fifty explanatory teaching slides, provided as supplementary material, allowed our expert group of raters to achieve a good level of agreement (kappa 0.701, 50 OCT scans, 21 raters). We recommend adopting the refined definition for PHOMS.

The Influence of Volume and Anatomic Location of Optic Disc Drusen on the Sensitivity of Autofluorescence.

BACKGROUND: Optic disc drusen (ODD) are acellular deposits in the optic nerve head. ODD can be diagnosed using different imaging modalities, including enhanced depth imaging optical coherence tomography (EDI-OCT) and autofluorescence (AF). It is unknown which factors determine the sensitivity of AF. The aim of this study was to investigate the effect of volume and anatomic location of ODD on the sensitivity of AF. METHODS: Cross-sectional study. RESULTS: A total of 38 patients (75 eyes) with ODD were included. In 12 of 75 eyes (16%) and in 11 of 38 patients (29%), EDI-OCT detected ODD that were not detected by AF. In 24 distinctly solitary ODD, both increase in ODD volume (P = 0.0388) and a more superficial ODD location (P < 0.0001) increased the possibility of AF detection of ODD, when performing a multivariate analysis. CONCLUSIONS: EDI-OCT is superior to AF in the diagnosis of ODD. Volume and anatomic location of ODD have a significant impact on the sensitivity of AF.

Optic Disc Drusen in Children: The Copenhagen Child Cohort 2000 Eye Study.

BACKGROUND: Optic disc drusen (ODD) are seen in up to 2.4% of the general population, but the etiology and pathophysiology of the condition is still unknown. The purpose of this study was to determine the prevalence of ODD in a population-based child cohort and to determine if scleral canal diameter and fetal birth and pubertal parameters are associated with the presence of ODD. METHODS: This observational, longitudinal population-based birth cohort study, with a nested case-control, included 1,406 children. Eye examinations were performed when the children were between 11 and 12 years of age. Assessment was performed of optical coherence tomography (OCT) scans from 1,304 children with gradable enhanced depth imaging scans of the optic disc. RESULTS: ODD in one or both eyes were found in 13 (1.0%) of all children. All but one of the cases were found in children with scleral canal diameter in the lowest quartile (1,182-1,399 µm) in the nested case-control study. Children with ODD had a mean disc diameter of 1,339 µm (interquartile range, 30 µm), whereas it was 1,508 µm (interquartile range, 196 µm) in the 130 controls without ODD (P < 0.001). No differences in sex, birth weight, refractive error, and Tanner stages (of puberty) were found between children with and without ODD. CONCLUSIONS: The prevalence of ODD was 1% in a large child cohort examined by OCT. ODD was found only in eyes with a narrow scleral canal, which is consistent with the hypothesis that ODD might arise as a consequence of retinal nerve fiber congestion in the scleral canal.

The Optic Disc Drusen Studies Consortium Recommendations for Diagnosis of Optic Disc Drusen Using Optical Coherence Tomography.

BACKGROUND: Making an accurate diagnosis of optic disc drusen (ODD) is important as part of the work-up for possible life-threatening optic disc edema. It also is important to follow the slowly progressive visual field defects many patients with ODD experience. The introduction of enhanced depth imaging optical coherence tomography (EDI-OCT) has improved the visualization of more deeply buried ODD. There is, however, no consensus regarding the diagnosis of ODD using OCT. The purpose of this study was to develop a consensus recommendation for diagnosing ODD using OCT. METHODS: The members of the Optic Disc Drusen Studies (ODDS) Consortium are either fellowship trained neuro-ophthalmologists with an interest in ODD, or researchers with an interest in ODD. Four standardization steps were performed by the consortium members with a focus on both image acquisition and diagnosis of ODD. RESULTS: Based on prior knowledge and experiences from the standardization steps, the ODDS Consortium reached a consensus regarding OCT acquisition and diagnosis of ODD. The recommendations from the ODDS Consortium include scanning protocol, data selection, data analysis, and nomenclature. CONCLUSIONS: The ODDS Consortium recommendations are important in the process of establishing a reliable and consistent diagnosis of ODD using OCT for both clinicians and researchers.

Peripapillary Retinal Nerve Fiber Layer Thickness Corresponds to Drusen Location and Extent of Visual Field Defects in Superficial and Buried Optic Disc Drusen.

BACKGROUND: Optic disc drusen (ODD) are hyaline deposits located within the optic nerve head. Peripapillary retinal nerve fiber layer (RNFL) thinning is associated with the high prevalence of visual field defects seen in ODD patients. The goal of this study was to investigate the characteristics of patients with ODD and to compare the peripapillary RNFL thickness to the extent of visual field defects and anatomic location (superficial or buried) of ODD. METHODS: Retrospective, cross sectional study. RESULTS: A total of 149 eyes of 84 ODD patients were evaluated. Sixty-five percent were female and 76% had bilateral ODD. Of 149 eyes, 109 had superficial ODD and 40 had buried ODD. Peripapillary RNFL thinning was seen in 83.6% of eyes, where optical coherence tomography was performed (n = 61). Eyes with superficial ODD had greater mean peripapillary RNFL thinning (P ≤ 0.0001) and visual field defects (P = 0.002) than eyes with buried ODD. There was a correlation between mean peripapillary RNFL thinning and visual field defects as measured by perimetric mean deviation (R-0.66; P = 0.0001). The most frequent visual field abnormalities were arcuate and partial arcuate defects. CONCLUSIONS: Peripapillary RNFL thickness correlates with anatomic location (superficial or buried) of ODD. Frequency and extent of visual field defects corresponded with anatomic location of ODD and peripapillary RNFL thickness, suggesting increased axonal damage in patients with superficial ODD.

Cardiac arrhythmias the first month after acute traumatic spinal cord injury.

OBJECTIVE: Cardiovascular complications including cardiac arrest and arrhythmias remain a clinical challenge in the management of acute traumatic spinal cord injury (SCI). Still, there is a lack of knowledge regarding the characteristics of arrhythmias in patients with acute traumatic SCI. The aim of this prospective observational study was to investigate the occurrence of cardiac arrhythmias and cardiac arrests in patients with acute traumatic SCI. METHODS: As early as possible after SCI 24-hour Holter monitoring was performed. Additional Holter recordings were performed 1, 2, 3, and 4 weeks after SCI. Furthermore, 12-lead electrocardiograms (ECGs) were obtained shortly after SCI and at 4 weeks. RESULTS: Thirty patients were included. Bradycardia (heart rate (HR) <50 b.p.m.) was present in 17-35% of the patients with cervical (C1-C8) SCI (n = 24) within the first 14 days. In the following 14 days, the occurrence was 22-32%. Bradycardia in the thoracic (Th1-Th12) SCI group (n = 6) was present in 17-33% during the observation period. The differences between the two groups were not statistically significant. The mean minimum HR was significantly lower in the cervical group compared with the thoracic group both on 12-lead ECGs obtained shortly after SCI (P = 0.030) and at 4 weeks (P = 0.041). CONCLUSION: Many patients with cervical SCI experience arrhythmias such as bradycardia, sinus node arrest, supraventricular tachycardia, and more rarely cardiac arrest the first month after SCI. Apart from sinus node arrests and limited bradycardia, no arrhythmias were seen in patients with thoracic SCI. Standard 12-lead ECGs will often miss the high prevalence these arrhythmias have.

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.

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.