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.

Visual Field Defects in Patients With Optic Nerve Head Drusen

Background Optic nerve head drusen (ONHD) are acellular deposits in the optic nerve head, whose pathophysiology remains not fully understood. Most patients with ONHD have visual field (VF) defects. This study aims to describe the VF defects observed in patients with ONHD and to compare the anatomical and functional impairment between visible and buried ONHD. Methods Patients with ONHD were retrospectively studied. The retinal nerve fiber layer (RNFL) average thickness and the ganglion cell complex (GCC) average thickness were collected from optical coherence tomography data. Visual field index (VFI), mean deviation (MD), and pattern standard deviation (PSD) were collected from 30-2 standard automated perimetry. An abnormal VF test was defined as having a Glaucoma Hemifield Test outside normal limits and/or a PSD with a p-value<5%. Eyes with superficial or buried ONHD based on visibility by slit-lamp ophthalmoscopy were compared. Results Sixty-six eyes of 36 patients were included in the study. The mean age was 39.6 ± 2.5 years. Forty-nine eyes (81.7%) presented a VF defect: concentric VF constriction in 19 (38.8%), arcuate scotoma in 16 (32.7%), enlarged blind spot in 9 (18.4%), unspecific VF defect in 8 (16.3%), and nasal step in 3 (6.1%). Thirty-four eyes (51.5%) had superficial ONHD and 32 eyes (48.5%) had buried ONHD. Patients with superficial ONHD were significantly older (p<0.001) and presented a significantly lower VFI (p=0.010), lower MD (p=0.002), higher PSD (p<0.001), thinner GCC (p<0.001), and thinner RNFL (p<0.001) than patients with buried ONHD. VF defects were present in 90.6% of eyes with superficial ONHD and 71.4% of eyes with buried ONHD (p=0.113). The type of VF defects differed between groups (p=0.020). Conclusions Functional and structural impairment is more evident in eyes with superficial ONHD, maybe because the presence of calcification leads to greater axonal damage. Buried ONHD is more prevalent in younger patients, progressing to a superficial location and becoming calcified with age.

Pseudoretinoblastoma: Distribution based on gender, age, and laterality

PURPOSE

To investigate the distribution of pseudoretinoblastoma (PSRB) cases based on gender, age, and laterality.

MATERIALS AND METHODS

The clinical records of 607 patients (851 eyes) who were referred for diagnosis of retinoblastoma or simulating conditions between October 1998 and May 2021 were retrospectively evaluated. Patients were stratified by age as follows: ≤1 year, >1-3 years, >3-5 years, and >5 years.

RESULTS

Of 190/607 PSRB patients, 129 (67.9%) were males and 61 (32.1%) females (p = 0.001). The 3 most common diagnoses in males were Coats disease (20.2%), persistent fetal vasculature (PFV, 14.0%), and chorioretinal coloboma (6.2%). In females, the 3 most common diagnoses included PFV (21.3%), retinal dysplasia, congenital glaucoma, and combined hamartoma (each 6.6%). PFV was the most common diagnosis in ≤1 year old patient group (26.6%). Coats disease and PFV were the most common diagnoses in >1-3 years old patient group (each 16.7%). Coats disease was the most common diagnosis in >3-5 years old (30.8%) and >5 years old patient groups (13.1%). PSRBs were unilateral in 121/190 (63.7%) patients. Coats disease usually presented unilaterally (p < 0.001) while PFV, optic nerve head drusen, and retinopathy of prematurity as bilateral diseases (p = 0.019, p = 0.001, and p = 0.001 respectively).

DISCUSSION

PSRB diagnoses show differences depending on gender, age, and laterality. In our study, the most common PSRB lesions were Coats disease in males and PFV in females. PFV was the most frequent diagnosis in ≤3 years and Coats disease in >3 years of age groups. Coats disease and PFV were the most common unilateral and bilateral PSRB diagnoses respectively.

Peripapillary Hyper-reflective Ovoid Mass-like Structure (PHOMS): An Optical Coherence Tomography Marker of Axoplasmic Stasis in the Optic Nerve Head

BACKGROUND

With the development and widespread adoption of spectral-domain optical coherence tomography (OCT), peripapillary hyper-reflective ovoid mass-like structures (PHOMS) have become a frequent OCT finding in neuro-ophthalmic practice. Although originally assumed to represent a form of buried optic disc drusen (ODD), PHOMS differ from ODD in many important ways. The histopathological underpinnings of PHOMS are now becoming more clearly understood.

EVIDENCE ACQUISITION

Review of literature.

RESULTS

PHOMS can be broadly classified as disk edema-associated PHOMS, ODD-associated PHOMS, or anomalous disk-associated PHOMS. PHOMS are seen in many conditions, including papilledema, nonarteritic anterior ischemic optic neuropathy, central retinal vein occlusion, acute demyelinating optic neuritis, ODD, and tilted disks (myopic obliquely inserted disks) and in many cases resolve along with the underlying condition. The histopathological study of these diverse entities reveals the common feature of a bulge of optic nerve fibers herniating centrifugally over Bruch membrane opening into the peripapillary space, correlating exactly with the location, shape, and space-occupying nature of PHOMS on OCT. Because of the radial symmetry of these herniating optic nerve fibers, PHOMS are best thought of as a complete or partial torus (i.e., donut) in 3 dimensions.

CONCLUSIONS

PHOMS are a common but nonspecific OCT marker of axoplasmic stasis in the optic nerve head. They are not themselves ODD or ODD precursors, although they can be seen in association with ODD and a wide spectrum of other conditions. They do not exclude papilledema and often accompany it. The circumferential extent and characteristic 3D toroidal nature of a PHOMS are best appreciated by scrolling through consecutive OCT images.

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 (MBR_V and MBR_T), 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 MBR_T 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.

Multimodal Imaging Characteristics of a Rare Co-occurrence of Optic Nerve Head Drusen and Peripapillary Myelinated Retinal Nerve Fibres

Although isolated optic nerve head drusen (ONHD) and peripapillary myelinated retinal nerve fibres (MRNF) are described in the literature many times as far as we could reach, the combination of the two has been reported in only a single case without multimodal imaging. Here, we present multimodal imaging of a 47-year-old healthy woman with MRNF who had blind spot enlargement and a visual field defect in the left eye ascribed to the ONHD. ONHD may accompany MRNF which can hide the disc drusen. Clinicians, therefore, should be aware of this rare coexistence to explain possible complications such as visual field defects associated with drusen in patients with MRNF.

Prevalence and histopathological signatures of optic disc drusen based on microscopy of 1713 enucleated eyes

PURPOSE

Optic disc drusen (ODD) are calcified optic nerve head deposits. Objectives of this study were to examine the prevalence of ODD in eyes removed by enucleation and to describe related histopathological signatures of ODD and surrounding tissues.

METHODS

The study was a retrospective observational case series study assessing and re-evaluating enucleated eyes in Denmark from 1980 to 2015 by microscopy. Individual ODD were described based on size, number and location (superficial and/or deep) within the optic nerve. Optic nerve heads with ODD were assessed for elevated discs, retinal nerve fibre layer (RNFL) thickness, oedematous axons and presence of localized peripapillary axonal distension (LPAD) equivalent to the peripapillary hyperreflective ovoid mass-like structures seen on optical coherence tomography.

RESULTS

Microscopy of 1713 eyes revealed ODD in 31 eyes equivalent to a prevalence of 1.8%. Optic disc drusen (ODD) were seen as circular shapes of different sizes and varying number. Elevated discs were present in 15 (54%) of the cases. Thickening of the superficial RNFL was present in eyes with large deeply located ODD. For more superficial ODD of approximately same size, the RNFL was thinner. Oedematous axons were present in three eyes. Localized peripapillary axonal distension (LPAD) was seen in five eyes.

CONCLUSIONS

Prevalence of ODD in this study of histopathological signatures was higher than the prevalence found in clinical studies. Our results suggest that large, deep ODD might cause crowding and herniation of axons in the optic nerve head leading to a thickened superficial nerve fibre layer, pseudopapilledema and LPAD.

OCT angiography in optic disc drusen: comparison with structural and functional parameters

BACKGROUND

Optic disc drusen (ODD) can cause retinal nerve fibre layer (RNFL) defects with progressive visual field (VF) loss. Microvascular changes are discussed as a cause. We measured the vessel density (VD) of the optic disc in ODD using optical coherence tomography angiography and compared it with a normal population. Another intent was to determine the sensitivity and correlations in comparison with functional (VF) and structural parameters (RNFL, minimum rim width (MRW), ganglion cell complex (GCC)).

METHODS

We analysed the VD of 25 patients with ODD and an age-matched control population including 25 healthy participants using AngioVue (Optovue, Fremont, CA, USA). We obtained data about RNFL, GCC, Bruch's membrane opening MRW (Spectralis HRA & OCT; Heidelberg Engineering, Germany) and VF (standard automated perimetry; SITA 24-2). Low image quality and pathologies interfering with the diagnostics were excluded. Parametric data were analysed using the t-test and non-parametric values using the Mann-Whitney U test. Linear regression analysis was used to determine correlations using the Bravais-Pearson test.

RESULTS

The VD was significantly reduced in the ODD group especially the peripapillary capillary VD (n=45 vs 50 eyes; mean 43.15% vs 51.70%). Peripapillary RNFL thickness correlated with the VD significantly (r=0.902 (n=44), 0.901 (n=44), 0.866 (n=45)). The RNFL analysis showed a reduction in ODD, especially the superior hemisphere (mean 107 µm, 129 µm; 49 vs 50 eyes). The GCC was significantly lower in the ODD group (n=38 vs 40; mean 87 µm vs 98 µm). Positive correlation between the VD and the GCC was significant (n=37, r=0.532). There is a significant negative correlation (n=19; r=-0.726) between the VD and the pattern standard deviation (PSD).

CONCLUSION

This study reveals significant peripapillary microvascular changes in patients with ODD correlating with the RNFL and GCC reduction. There is a negative correlation between the PSD and the VD.

One-year outcomes of anti-vascular endothelial growth factor therapy in peripapillary choroidal neovascularisation

PURPOSE

To report the visual and anatomical outcomes in eyes with peripapillary choroidal neovascularisation (CNV) through 12 months.

METHODS

This was a multicentre, retrospective, interventional case series which included treatment-naïve cases of peripapillary choroidal neovascular membrane (CNVM) with a minimum follow-up of 12 months. Multimodal imaging which comprised optical coherence tomography (OCT), fluorescein angiography and/or indocyanine green angiography was performed at baseline and follow-up visits. OCT parameters included central macular thickness (CMT), subfoveal choroidal thickness (SFCT) and retinal and choroidal thickness at site of CNV. Patients were treated with anti-vascular endothelial growth factors (VEGF) on pro re nata protocol, photodynamic therapy, laser photocoagulation or a combination. Main outcome measures were change in best corrected visual acuity (BCVA) and OCT parameters.

RESULTS

A total of 77 eyes (74 patients; mean age: 61.9±21.8 years) with a mean disease duration of 9.2±14.1 months were included. BCVA improved significantly from 0.55±0.54 logMAR (20/70) at baseline to 0.29±0.39 logMAR (20/40) at 12 months (p<0.001) with a mean of 4.9±2.9 anti-VEGF injections. CMT, SFCT and retinal thickness at site of CNVM reduced significantly (p<0.001, <0.001 and 0.02, respectively) through 12 months. The most common disease aetiologies were neovascular age-related macular degeneration, and idiopathic, inflammatory and angioid streaks. Age (p=0.04) and baseline BCVA (p<0.001) were significant predictors of change in BCVA at 12 months.

CONCLUSION

Peripapillary CNVM, though uncommon, is associated with diverse aetiologies. Anti-VEGF agents lead to significant visual acuity and anatomical improvement in these eyes over long term irrespective of the aetiology.

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.

Optic disc drusen: understanding an old problem from a new perspective

Optic disc drusen (ODD) are acellular deposits located in the optic nerve head of up to 2.4% of the population. They may develop as by-products of impaired axonal metabolism in genetically predisposed individuals, in whom a narrow scleral canal is hypothesized to play a role. Although ODD are often considered as benign innocent bystanders, recognized as part of a routine ophthalmological examination, the vast majority of patients with ODD have visual field defects. Optic disc drusen (ODD)-associated complications with severe visual loss, most often due to anterior ischaemic optic neuropathy, are also known to occur. There are no treatments available to prevent or ameliorate the vision loss caused by ODD. In children, the ODD are usually uncalcified and buried within the optic nerve head tissue. In these cases, the condition can be difficult to diagnose, as it often resembles a papilloedema with optic nerve head swelling caused by raised intracranial pressure. During the teenage years, the ODD progressively become more calcified and probably also larger, which allow them to be visible on ophthalmoscopy. With the advent and proper utilization of high-resolution modalities of optical coherence tomography (OCT), it has now become possible to detect even the smallest and most deeply located ODD. This allows for ODD detection at a much earlier developmental stage than has previously been possible and enhances the possibilities of research in underlying mechanisms. A review of the literature on ODD was conducted using the PUBMED database. The review focuses on the current knowledge regarding pathogenesis, diagnostics, clinical disease-tracking methodologies, structure-function relationships and treatment strategies of ODD.

Acute Unilateral Anterior Ischemic Optic Neuropathy Secondary to Optic Nerve Head Drusen: Report of a Rare Coexistence

A 45-year-old white male noticed on awakening the painless loss of inferior vision in the left eye 2 days ago. He was otherwise well and his medical history was unremarkable. Visual acuity was 20/20 in OD and 20/32 in OS with a left inferior altitudinal defect and right blind spot enlargement demonstrable on visual field test. On fundus examination, both disc margins were blurred and the left disc was diffusely oedematous, with linear haemorrhages in the adjacent nerve fibre layer. Radiologic imaging and laboratory tests were unremarkable. Bilateral optic nerve head drusen (ONHD) was demonstrated by optical coherence tomography and fundus autofluorescence imaging. Unilateral acute non-arteritic anterior ischemic optic neuropathy (NAION) and concomitant bilateral ONHD were diagnosed. NAION may develop secondary to ONHD. Therefore, clinicians should be aware of this rare association and inform the patients about this risk. Patients with ONHD should be followed-up periodically in terms of possible ischemic complications.

Long-term evolution of superficial optic disc drusen

PURPOSE

Optic disc drusen (ODD) is hyaline deposits in the optic nerve head seen in 1-2% of the population. Long-term evolution of ODD anatomy and visual field defects in ODD patients is a key factor for learning more about pathophysiology and prognosis of the condition. With a median follow-up period of 56 years, this is the first study that evaluates superficial optic disc anatomy and visual fields in patients with ODD over a life span.

METHODS

Observational case series investigating progression of superficial optic disc anatomy and visual fields in ODD patients. Eight patients with hereditary ODD were included.

RESULTS

Mean age at initial and follow-up examination was, respectively, 16.8 and 73.3 years. The median follow-up time was 56 years. A minimal or non-existing change in superficial ODD anatomy (size and number) was seen in 10 of 12 eyes. There was a tendency towards more anatomical change in subjects younger at first examination. A 27% decrease in Goldmann perimetric visual field area (cm² ) was found between initial and follow-up examinations.

CONCLUSION

Minimal or no change in superficial optic disc anatomy and visual fields in ODD patients oldest at the initial examination suggests that anatomical progression of ODD in patients with hereditary ODD happens primarily before adulthood.

Case report: bilateral optic nerve head drusen and glaucoma

Optic nerve head drusen is an incidental finding in current ophthalmological practice. Although patients rarely display symptoms, structural, and functional defects, there are exceptional cases when clinical appearance can make it difficult to diagnose underlying or coexisting conditions, such as glaucoma. The following case report demonstrates how overlapping optic nerve pathologies can interfere in clinical judgement and therapeutic decision making in a young male patient, with relevant family history for both glaucoma and bilateral optic nerve head drusen.

Equating spatial summation in visual field testing reveals greater loss in optic nerve disease

PURPOSE

To test the hypothesis that visual field assessment in ocular disease measured with target stimuli within or close to complete spatial summation results in larger threshold elevation compared to when measured with the standard Goldmann III target size. The hypothesis predicts a greater loss will be identified in ocular disease. Additionally, we sought to develop a theoretical framework that would allow comparisons of thresholds with disease progression when using different Goldmann targets.

METHODS

The Humphrey Field Analyser (HFA) 30-2 grid was used in 13 patients with early/established optic nerve disease using the current Goldmann III target size or a combination of the three smallest stimuli (target size I, II and III). We used data from control subjects at each of the visual field locations for the different target sizes to establish the number of failed points (events) for the patients with optic nerve disease, as well as global indices for mean deviation (MD) and pattern standard deviation (PSD).

RESULTS

The 30-2 visual field testing using alternate target size stimuli showed that all 13 patients displayed more defects (events) compared to the standard Goldmann III target size. The median increase for events was seven additional failed points: (range 1-26). The global indices also increased when the new testing approach was used (MD -3.47 to -6.25 dB and PSD 4.32 to 6.63 dB). Spatial summation mapping showed an increase in critical area (Ac) in disease and overall increase in thresholds when smaller target stimuli were used.

CONCLUSIONS

When compared to the current Goldmann III paradigm, the use of alternate sized targets within the 30-2 testing protocol revealed a greater loss in patients with optic nerve disease for both event analysis and global indices (MD and PSD). We therefore provide evidence in a clinical setting that target size is important in visual field testing.

Bilateral optic nerve head drusen with chorioretinal coloboma in the right eye

Chorioretinal coloboma is a congenital defect of the eye caused by improper closure of the embryonic fissure. Optic nerve head drusen (ONHD) are white calcareous deposits that are generally asymptomatic. We report a very rare association of both in a healthy patient with no any systemic syndrome. A 16-year-old man was referred to our clinic from suffering blurred vision. Best corrected visual acuity of the right eye was 6/10 and 10/10 in the left one. External ocular and slit lamp examination were normal. Dilated ophthalmoscopy showed marked swelling in both optic nerves and chorioretinal coloboma in the right eye inferiorly. Ultrasonography showed an echodense structure with acoustic shadowing in both eyes consistent with buried ONHD. Visual field testing showed normal field in the left eye and moderate superior field depression in the right eye corresponding to inferior coloboma in funduscopy. Results of general medical and neurologic, cardiologic, and other examinations were normal. To the best our knowledge combination of bilateral ONHD and unilateral chorioretinal coloboma in a healthy patient with no any systemic syndrome has not been published in the literature. We reported this very rare association and recommended examine eyes and other body organs. In such cases that coloboma is associated with ONHD, we should keep in mind Noonan syndrome. The diagnosis of Noonan syndrome is clinical and confirm by the consultant pediatricians and clinical geneticists.

Bilateral choroidal neovascularization associated with optic nerve head drusen treated by antivascular endothelial growth factor therapy

OBJECTIVE

To report a good clinical outcome in a patient with bilateral choroidal neovascularization (CNV) associated with optic nerve head drusen (ONHD) treated with intravitreal ranibizumab injection.

METHODS

A 12-year-old girl was referred for loss of right eye vision detected in a routine check-up. Best-corrected visual acuity (BCVA) was hand movements in the right eye and 0.9 in the left eye. Funduscopy revealed the presence of superficial and buried bilateral ONHD, which was confirmed by ultrasonography and computed tomography, and the study was completed with perimetry. The presence of bilateral CNV, active in the right eye, was observed and subsequently confirmed using fluorescein angiography and optical coherence tomography.

RESULTS

Treatment with two consecutive injections of intravitreal ranibizumab resulted in inactivation of the neovascular membrane with subretinal fluid reabsorption and improved right eye BCVA. After 12 months' follow-up, this was 20/60 and stable.

CONCLUSION

Although there are no published studies of safety in children, antiangiogenic therapy for CNV secondary to ONHD may be useful and safe. A search of the literature produced only one previously reported case of ONHD-associated CNV treated with antivascular endothelial growth factor alone.

Bilateral presumed astrocytic hamartomas in a patient with retinitis pigmentosa

Retinal astrocytic hamartomas are benign intraocular tumors classically associated with phacomatoses. Their appearance in isolation is rare. An association between astrocytic hamartomas and retinitis pigmentosa (RP) has been described previously, but controversy still exists regarding the precise nature of these lesions in RP patients. The authors present a case report of a 24-year-old male with RP and multiple bilateral lesions clinically consistent with retinal astrocytic hamartomas. Optical coherence tomography revealed multiple bilateral hyper-reflective intraretinal masses, loss of retinal architecture, intralesional calcifications, and prominent optical posterior shadowing. Comprehensive systemic evaluation was negative for phacomatoses. However, given that a biopsy was not performed, the diagnosis of optic nerve head drusen could not be excluded.