Spectral-domain optical coherence tomography findings in pediatric tilted disc syndrome

Diagnostic dilemma of papilledema and pseudopapilledema

BACKGROUND

Papilledema is the optic disc swelling caused by increased intracranial pressure (ICP) that can damage the optic nerve and cause subsequent vision loss. Pseudopapilledema refers to optic disc elevation without peripapillary fluid that can arise from several optic disc disorders, with optic disc drusen (ODD) being the most frequent cause. Occasionally, pseudopapilledema patients are mistakenly diagnosed as papilledema, leading to the possibility of unneeded procedures. We aim to thoroughly examine the most current evidence on papilledema and pseudopapilledema causes and several methods for distinguishing between both conditions.

METHODS

An extensive literature search was conducted on electronic databases including PubMed and google scholar using keywords that were relevant to the assessed pathologies. Data were collected and then summarized in comprehensive form.

RESULTS

Various techniques are employed to distinguish between papilledema and pseudopapilledema. These techniques include Fundus fluorescein angiography, optical coherence tomography, ultrasonography, and magnetic resonance imaging. Lumbar puncture and other invasive procedures may be needed if results are suspicious.

CONCLUSION

Papilledema is a sight-threatening condition that may lead to visual affection. Many disc conditions may mimic papilledema. Accordingly, differentiation between papilledema and pseudopailledema is crucial and can be conducted through many modalities.

Peripapillary hyperreflective ovoid mass-like structures: multimodal imaging and associated diseases

Growing evidence has demonstrated that peripapillary hyperreflective ovoid mass-like structures (PHOMS) are novel structures rather than a subtype of optic disc drusen. They correspond to the laterally bulging herniation of optic nerve fibers and are believed to be the marker of axoplasmic stasis. PHOMS present in a broad spectrum of diseases, including optic disc drusen, tilted disc syndrome, papilloedema, multiple sclerosis, non-arteritic anterior ischemic optic neuropathy, optic neuritis, Leber hereditary optic neuropathy, and so on. We focus on the multimodal imaging features, pathophysiological mechanisms of PHOMS, and their association with multiple diseases and healthy people in this review to deepen the ophthalmologists' understanding of PHOMS. Additionally, we provide some new directions for future research.

Peripapillary hyperreflective ovoid mass-like structures (PHOMS) in patients with acute Leber's hereditary optic neuropathy

PURPOSE

Peripapillary hyperreflective ovoid mass-like structures (PHOMS) represent an optical coherence tomography (OCT) finding that has been characterized in different forms of pseudopapilledema. The aim of this study was to investigate the prevalence of PHOMS in patients affected by acute LHON using structural OCT, and to provide a detailed description of these findings.

METHODS

Patients with a clinical and molecularly confirmed diagnosis of acute LHON (visual loss having occurred less than 6 months) were enrolled from the neuro-ophthalmology clinic at San Raffaele Scientific Institute. Patients had a complete ophthalmologic evaluation, including imaging with structural OCT.

RESULTS

Our analysis included 16 patients (21 eyes-8 males and 8 females) with acute LHON. Structural OCT exhibited PHOMS in 12 eyes from 9 patients with a prevalence rate of 57.1%. In a subsequent topographical assessment in the peripapillary area, the most common location of PHOMS was the temporal region (12 out of 12 eyes), while the nasal region was affected in 2 eyes (16.7%). Considering the 12 eyes with PHOMS, mean ± SD temporal peripapillary RNFL thickness was 87.5 ± 28.4 microns. The temporal peripapillary RNFL thickness was significantly lower in eyes without PHOMS (63.7 ± 32.2 microns; P = 0.40). At the 12-month follow-up visit, PHOMS disappeared in 10 out of 12 eyes.

CONCLUSIONS

Acute LHON eyes have PHOMS which are mainly confined to the temporal peripapillary sector. PHOMS may represent swelled retinal fibers that have herniated or are in stasis.

Deep Optic Nerve Head Morphology in Tilted Disc Syndrome and Its Clinical Implication on Visual Damage

Purpose

To study deep optic nerve head (ONH) morphology in tilted disc syndrome (TDS) and identify factors associated with retinal nerve fiber layer (RNFL) defect.

Methods

In patients with TDS, we evaluated the optic disc shape using the Bruch's membrane opening (BMO)-anterior scleral canal opening (ASCO) offset and measured the border tissue (BT) length, depth, and angle in the direction of the tilt, using radial ONH optical coherence tomography (OCT). We compared the parameters between the TDS groups with and without RNFL defects.

Results

Twenty-one eyes had no glaucomatous RNFL defect, and 38 eyes had a glaucomatous RNFL defect. The group with RNFL defects had a higher baseline IOP, larger tilt axis of BMO-ASCO optic disc margin (76.4° ± 14.5° vs. 87.9° ± 15.4°, P = 0.012), larger BMO-lamina cribrosa insertion (LCI) angle (25.6° ± 9.3° vs. 43.6° ± 15.2°, P < 0.001), and more lamina cribrosa (LC) defects (4.3% vs. 30.6%, P = 0.028) than without RNFL defects. The tilt axis and BMO-LCI angle were significant factors after adjusting for baseline IOP and LC defect. The BMO-LCI angle had excellent diagnostic power for glaucomatous RNFL defect in TDS, similar to the visual field mean deviation.

Conclusions

OCT-based large deep ONH BT angle and tilt axis were factors associated with the presence of RNFL defects in TDS. The results suggest a mechanism of RNFL defect associated with structural ONH deformation. Further investigations are warranted to understand the role of ONH structures in a general population with and without optic disc tilt.

Are PHOMS a clinical sign of optic neuritis?

PURPOSE

Assess the prevalence and evolution of PHOMS in optic neuritis.

METHODS

We analysed the medical files of 126 patients included in the OCTON cohort. Patients' medical files, digital retinal images and OCT examinations were reviewed, searching for optic nerve head oedema and PHOMS at the initial presentation and during the follow-up.

RESULTS

We included 102 patients in the final analysis. Twenty-nine (29) eyes had optic nerve head oedema at the initial presentation. PHOMS were found to be present in 8 eyes affected with optic neuritis. All cases of PHOMS were associated with optic nerve head oedema. All the PHOMS decreased in size and disappeared with the improvement of the oedema.

DISCUSSION

Our results show that PHOMS is not a common sign of optic neuritis. We didn't observe any case of PHOMS in the absence of optic nerve head oedema in eyes with optic neuritis. PHOMS seem to be a rare sign of optic neuritis associated to optic nerve head oedema, and they tend to disappear with the improvement of the optic nerve head oedema. We suggest that the presence of PHOMS in optic neuritis eyes with no optic nerve oedema should be a considered warning sign.

Peripapillary hyper-reflective ovoid mass-like structures (PHOMS): clinical significance, associations, and prognostic implications in ophthalmic conditions

Pioneering advancements in optical coherence tomography (OCT) have facilitated the discernment of peripapillary hyper-reflective ovoid mass-like structures (PHOMS), prevalent neuro-ophthalmological findings associated with an array of ophthalmic conditions, such as optic disc drusen (ODD), papilledema, myopic/tilted optic discs, non-arteritic anterior ischemic optic neuropathy (NA-AION), and optic neuritis. Despite an expanding corpus of research, numerous inquiries persist concerning their clinical significance, correlations with ocular afflictions, and prognostic implications. This comprehensive review endeavors to impart an in-depth comprehension of PHOMS, encompassing facets like conceptualization, detection, pathogenesis, and associations with diverse ophthalmic conditions. Furthermore, we underscore several unresolved quandaries and suggest prospective avenues for future exploration.

Morphology and microcirculation changes of the optic nerve head between simple high myopia and pathologic myopia

PURPOSE

To investigate morphological and microcirculation changes of optic nerve head (ONH) in simple high myopia (SHM) and pathologic myopia(PM) to evaluate and identify ONH changes in the development of PM.

METHODS

A cross-sectional clinical study was used. Medical records from 193 right eyes of 193 patients with high myopia (HM) were included. Using the Topocon swept source optical coherence tomograph (SS-OCT) and fundus camera to detect the parameters, we have assessed the relative position and size of ONH, tilt and rotation of ONH, angle α (Defined as between retinal temporal arterial vascular arcades was measured from the centre of ONH with 250 pixels' radius), size and type of peripapillary atrophy (PPA), the thickness of peripapillary retinal nerve fiber layer (PRNFL), peripapillary choriodal thickness (PCT) and peripapillary scleral thickness (PST), and peripapillary vessel density (PVD). In addition, subjects were grouped as SHM and PM according to retinopathy, and the above parameters were compared between the two groups.

RESULTS

Patients were divided into the SHM group (138 eyes) and the PM group (55 eyes). Paramters like older age, higher diopter and longer axial length (AL) of the PM were compared to SHM (t=-3.585, -8.808, -11.409, all P<0.05). There were no differences in the smallest diameter and area of ONH, rotation angle and ratio, or PST (all P>0.05). The angle α in PM was smaller than that in SHM (t = 2.728, P<0.01). The disc-fovea distance (DFD), the largest diameter, tilt index and ratio, PPA area and radian in PM were larger than in SHM (t=-3.962, Z=-2.525, t=-2.229, Z=-4.303, Z=-2.834, all P<0.05). The superior and inferior PRNFLs in PM were smaller than in SHM (t = 4.172, 4.263, all P<0.01). The temporoinferior PRNFL was the opposite (t=-2.421, P<0.01). The average PCT in PM (93.82 ± 29.96 μm) was smaller than in SHM (108.75 ± 30.70 μm) (P<0.05). The PVD in each direction of PM was smaller than that in SHM (t = 6.398, 4.196, 4.971, 3.267, 5.029, 5.653, 4.202, 5.146, 2.090, all P<0.05).

CONCLUSION

Compared with SHM, the PM patients were older, with higher diopter. Their AL and DFD were longer, the angle α was smaller, the tilt index was more extensive, the PPA area and radian were larger, PCT was generally thinner, and PVD was lower. When the PPA area was bigger than the ONH area, this already indicated the presence of PM. Based on these results, we suggest ophthalmologists and myopia patients pay more attention to ONH's morphology and microcirculation changes as there is a possibility that microcirculatory changes precede morphologic changes.

Diagnosis of Optic Disc Oedema: Fundus Features, Ocular Imaging Findings, and Artificial Intelligence

Optic disc swelling is a manifestation of a broad range of processes affecting the optic nerve head and/or the anterior segment of the optic nerve. Accurately diagnosing optic disc oedema, grading its severity, and recognising its cause, is crucial in order to treat patients in a timely manner and limit vision loss. Some ocular fundus features, in light of a patient's history and visual symptoms, may suggest a specific mechanism or aetiology of the visible disc oedema, but current criteria can at most enable an educated guess as to the most likely cause. In many cases only the clinical evolution and ancillary testing can inform the exact diagnosis. The development of ocular fundus imaging, including colour fundus photography, fluorescein angiography, optical coherence tomography, and multimodal imaging, has provided assistance in quantifying swelling, distinguishing true optic disc oedema from pseudo-optic disc oedema, and differentiating among the numerous causes of acute optic disc oedema. However, the diagnosis of disc oedema is often delayed or not made in busy emergency departments and outpatient neurology clinics. Indeed, most non-eye care providers are not able to accurately perform ocular fundus examination, increasing the risk of diagnostic errors in acute neurological settings. The implementation of non-mydriatic fundus photography and artificial intelligence technology in the diagnostic process addresses these important gaps in clinical practice.

Peripapillary hyperreflective ovoid mass-like structures: Multimodal imaging-A review

Peripapillary hyperreflective ovoid mass-like structures (PHOMS) are a laterally bulging herniation of distended axons into the peripapillary region above the level of Bruch's membrane opening. Increased use of enhanced depth imaging-optical coherence tomography (EDI-OCT) in our evaluation of the optic nerve head (ONH) and greater recognition of the vast range of optic nerve pathologies with which PHOMS is associated provides convincing evidence that PHOMS is not just buried optic disc drusen (ODD) as previously described. The frequent coexistence of PHOMS with ODD, papilloedema, anterior ischaemic optic neuropathy, tilted optic disc syndrome, inflammatory demyelinating disorders and other diseases associated with axoplasmic stasis provides insight into its underlying pathophysiology. The present review will discuss the role of key imaging modalities in the differential diagnosis of PHOMS, explore the current literature on the relationship between PHOMS and common neuro-ophthalmic conditions, and highlight the gaps in our knowledge, with respect to disease classification and prognosis, to pave the way for future directions of research.

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.

An overview of peripapillary hyperreflective ovoid mass-like structures

PURPOSE OF REVIEW

The purpose of this review is to provide an overview of the ophthalmic findings associated with peripapillary hyperreflective ovoid mass-like structures (PHOMS) in both adult and pediatric patients.

RECENT FINDINGS

PHOMS have recently been identified in a number of different ophthalmic disease entities ranging from nonpathologic to pathologic, including but not limited to anatomic abnormalities (tilting in myopia), optic nerve head drusen, optic disc edema from inflammation (optic neuritis, white dot syndromes), vascular insults (ischemic optic neuropathy, retinal vascular occlusion), and papilledema. The mechanism underlying the formation of PHOMS has not been fully elucidated although it has been hypothesized that PHOMS occur secondary to axoplasmic stasis from crowding at the optic nerve head.

SUMMARY

Although the clinical significance of the presence of PHOMS remains unclear, PHOMS are associated with several disease processes. Understanding the mechanism behind their formation and their impact on optic nerve head structure and visual function may be relevant in patients with optic nerve head pathology. The presence of PHOMS may also correlate with disease severity and duration. Future studies to evaluate whether the formation of PHOMS may be useful as an early indicator of disease or a prognostic tool are warranted.

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.

Clinical and Multi-Mode Imaging Features of Eyes With Peripapillary Hyperreflective Ovoid Mass-Like Structures

Purpose

To observe and analyze the clinical and multi-mode imaging features of eyes with PHOMS, and to introduce two cases of PHOMS which underwent multi-mode imaging.

Methods

Retrospective clinical observational study. A total of 26 patients (37 eyes) with hyperreflective structures surrounded by hyporeflective edges around the optic discs who were examined and diagnosed at Shandong Eye Hospital between January 2019 and June 2021 were included in the study. Among these patients, 12 were male and 14 were female. Fifteen were monocular. The average age was 39 years. All patients underwent the following examinations: Best-corrected visual acuity (BCVA), intraocular pressure examinations, slit-lamp anterior segment examinations, indirect ophthalmoscopy, visual field examinations, fundus color photography, fundus autofluorescence (FAF), optical coherence tomography (OCT), and optical coherence tomography angiography (OCTA). Some of the patients were examined with fundus fluorescein angiography (FFA). Clinical data and imaging characteristics from the OCT, OCTA, and FFA were analyzed retrospectively.

Results

We found the hyperreflective structures surrounded by hyporeflective edges around the optic discs in 37 eyes. EDI-OCT results revealed hyperreflective structures surrounded by hyporeflective edges around the optic discs in all eyes. Typical hyperreflexia lesions occurred around the optic disc, located subretinally and above Bruch's membrane. OCTA revealed that the highly reflective perioptic material also had vascular structures.

Conclusion

EDI-OCT of PHOMS showed hyperreflective structures surrounded by hyporeflective edges around all of the optic discs. Infra-red photography showed temporal hyperreflexia. These characteristics can be seen in a variety of diseases and may be a relatively common feature revealed by EDI-OCT scanning. These characteristics may also be seen in elderly patients as well as children. PHOMS may be found in optic disc drusen (ODD), tilted disc syndrome (TDS), optic neuritis, ischemic optic neuropathy, and in white dot syndromes. Few patients may be developed into macular neovascularization (MNV). In order to improve the accuracy and robustness of the conclusions and provide better clinical guidance, we need to conduct more comprehensive research in the subsequent clinical work.

Peripapillary hyper-reflective ovoid mass-like structure and dome-shaped maculopathy: A case report

RATIONALE

Peripapillary hyperreflective ovoid mass-like structures (PHOMS) and dome-shaped macula (DSM) are 2 optical coherence tomography findings reported in 2018 and 2008, respectively. To date, there have been no ophthalmic case reports of concomitant PHOMS and DSM.

PATIENT CONCERNS

A 19-year-old woman presented to our clinic with complaints of decreased vision in both eyes.

DIAGNOSIS

The patient was diagnosed with PHOMS and a dome-shaped macula complicated by subretinal fluid in both eyes.

INTERVENTIONS

A micropulse laser under the guidance of Indocyanine green angiography was applied to the hyperfluorescent areas and drugs to improve retinal microcirculation.

OUTCOMES

No response to any intervention over the 41 months of follow-up, her visual acuity remained the same, and the subretinal fluid often recurred.

LESSONS

PHOMS and DSM are associated with myopia; myopia may be a mediator between PHOMS and DSM. Dome-like structural changes may occur in different parts of the retina (optic disc and macula), caused by asymmetric myopic posterior scleral growth.

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.

Tilted disc syndrome (TDS): New hypotheses for posterior segment complications and their implications in other retinal diseases

Tilted disc syndrome (TDS) is considered a congenital anomaly due to a delayed closure of the embryonic fissure. It is characterized by an oblique orientation of the axis of the optic disc, associated with other posterior pole anomalies such as inferior crescent, situs inversus and inferior staphyloma. The aim of this review was to summarize the data supporting the current hypotheses for the pathogenesis of TDS, and its anatomical and functional clinical consequences. Recent imaging techniques, such as magnetic resonance imaging, wide-field fundus imaging, and 2- and 3-D optical coherence tomography have provided a new perspective on TDS and its complications. Different abnormalities have previously been reported, both in the anterior and posterior segments. The focus was on vision-threatening chorioretinal changes or complications, including choroidal neovascularization and serous retinal detachments and their therapeutic options. Based on clinical observations, assumptions were proposed to understand the occurrence of complications such as chorioretinal degenerative changes, choroidal neovascularization and polypoidal choroidal vasculopathy, macular serous retinal detachment, myopic foveoschisis and chorioretinal folds. These hypotheses could be referred to as the curvature "breaking point" hypothesis, the uneven growth "tractional" hypothesis, the "container-content" imbalance hypothesis, and the "choroidal funnel" hypothesis. Because these complications could also occur in other contexts, understanding the pathogenesis of TDS complications could help to understand their pathophysiology.

ODTiD: Optic Nerve Head SD-OCT Image Dataset

Introduction

Optic disc tilt (ODT) or tilted optic disc is a common finding in the general population. It is due to anomalous development caused by the malclosure of the embryonic optic fissure. ODT is commonly associated with high myopia as well as other conditions. In recent days, the common method to image the optic disc (OD) is by optical coherence tomography (OCT). To the best of our knowledge, there are no datasets of ODT available in the public domain. This dataset aims to make open access raw ODT OCT images to test out new image processing segmentation algorithms.

Methods

This dataset of ODT images contains both horizontal and vertical cross-sectional images obtained using spectral-domain optical coherence tomography (SD-OCT, Cirrus 5000, Carl Zeiss Meditec Inc., Dublin, CA). The optic disc cube 200×200 program was used and all the images are aligned with the center of the optic nerve head. This dataset includes images from both clinically normal (20 eyes) and myopic subjects (101 eyes).

Results

The dataset consists of clear (121) and manually marked (121) images resulting in a total of 242 images. The age distribution for all subjects combined is 27.24 ± 9.28 (range, 11.0-69.0) years. For normal subjects mean ± SD age distribution is 32.40 ± 17.23 years. Similarly, the myopia age distribution is 26.22 ± 6.37 years. Ground truth images, ie, manually segmented by a clinical expert are provided along with other meta-data includes age, gender, laterality, refractive error classification, spherical equivalent (SE), best-corrected visual acuity (BCVA), intraocular pressure (IOP), and axial length (AXL).

Conclusion

This open, public database is online at the ICPSR website of the University of Michigan. The dataset can be used to test and validate newly developed automated segmentation algorithms.

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.

Optical Coherence Tomography Neuro-Toolbox for the Diagnosis and Management of Papilledema, Optic Disc Edema, and Pseudopapilledema

BACKGROUND

Distinguishing optic disc edema from pseudopapilledema is a common, sometimes challenging clinical problem. Advances in spectral-domain optical coherence tomography (SD-OCT) of the optic nerve head (ONH) has proven to be a cost effective, noninvasive, outpatient procedure that may help. At its core are tools that quantify the thickness of the retinal nerve fiber layer (RNFL) and ganglion cell-inner plexiform layer (GC-IPL). The SD-OCT also provides a set of tools that may be qualitatively interpreted in the same way that we read an MRI. They include the transverse axial, en face, and circular tomogram. Our goal is to describe a practical office-based set of tools using SD-OCT in the diagnosis and monitoring of papilledema, optic disc edema, and pseudopapilledema.

EVIDENCE ACQUISITION

Searches on PubMed were performed using combinations of the following key words: OCT, papilledema, pseudopapilledema, optic disc drusen, retinal folds (RF), and choroidal folds (CF).

RESULTS

The principal elements of SD-OCT analysis of the ONH are the RNFL and GC-IPL thickness; however, these metrics have limitations when swelling is severe. Qualitative interpretation of the transverse axial SD-OCT aids in assessing peripapillary shape that may help distinguish papilledema from pseudopapilledema, evaluate atypical optic neuropathies, diagnose shunt failures, and identify outer RF and CF. There is a consensus that the SD-OCT is the most sensitive way of identifying buried optic disc drusen. En face SD-OCT is especially effective at detecting peripapillary wrinkles and outer retinal creases, both of which are common and distinctive signs of optic disc edema that rule out pseudopapilledema. Mechanically stressing the ONH in the adducted eye position, in patients with papilledema, may expose folds and peripapillary deformations that may not be evident in primary position. We also discuss how to optimize the acquisition and registration of SD-OCT images.

CONCLUSIONS

The SD-OCT is not a substitute for a complete history and a careful examination. It is, however, a convenient ancillary test that aids in the diagnosis and management of papilledema, optic disc edema, and pseudopapilledema. It is particularly helpful in monitoring changes over the course of time and distinguishing low-grade papilledema from buried drusen. The application of the SD-OCT toolbox depends on optimizing the acquisition of images, understanding its limitations, recognizing common artifacts, and accurately interpreting images in the context of both history and clinical findings.

Peripapillary hyperreflective ovoid mass-like structures (PHOMS): OCTA may reveal new findings

PURPOSE

Peripapillary hyperreflective ovoid mass-like structures (PHOMS) are novel and not well characterized findings occurring in several disorders of the optic nerve. The aim of this study is to present two cases of tilted disc syndrome (TDS) and one case with optic disc drusen undergoing a multimodal imaging approach.

METHODS

In this case series, a qualitative evaluation of the OCTA findings in regions with PHOMS was performed.

RESULTS

Structural OCT revealed the presence of PHOMS. OCTA identified the presence of a vascular complex within this hyperreflective structure.

CONCLUSIONS

Assuming that PHOMS are thought to correspond to herniating nerve fibers or be secondary to axoplasmic stasis, this vascular complex may represent a displacement of the deeper vessels deputed at the irroration of the optic nerve into the retina or, alternatively, might be secondary to an increase in vascular endothelial growth factor (VEGF) levels and a subsequent development of neovessels.

Diagnosing Optic Disc Drusen in the Modern Imaging Era: A Practical Approach

Optic disc drusen (ODD) are a well-recognised cause of an elevated optic disc appearance. When visible with ophthalmoscopy and fundus photography, ODD are readily identified. Yet, in more subtle cases of ODD, ancillary testing may be needed to render the diagnosis. Facilitating the diagnosis of ODD has clinical relevance, because affected individuals may otherwise undergo unnecessary costly and invasive investigations to rule out raised intracranial pressure and other causes of optic disc oedema. In this review, the role of established and emerging optical coherence tomography (OCT) techniques in the diagnosis and management of ODD cases is reviewed. A practical approach is taken to explain how to optimise use of commercially available OCT technology in the clinical setting. Optical coherence tomography provides many advantages over other imaging modalities in the diagnosis of ODD, including the ability to correlate retinal measures of neuroaxonal structure with drusen characteristics. Earlier spectral domain OCT techniques, however, were hindered by poor penetrance. In the modern imaging era, enhanced depth imaging OCT and swept source OCT enable higher resolution of ODD and other optic nerve head structures that might otherwise be mistaken for drusen. Ongoing studies featuring OCT angiography indicate that this technique may provide complementary information about microvascular supply that correlate with structural measures of optic nerve injury. Advances in OCT will continue to improve diagnostic accuracy and inform clinical understanding regarding structure-function correlations germane to the longitudinal follow up of 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.

Association between myopia and peripapillary hyperreflective ovoid mass-like structures in children

We investigated the characteristics of children with peripapillary hyperreflective ovoid mass-like structures (PHOMS) and evaluated the associated risk factors. This cross-sectional study included 132 eyes of 66 children with PHOMS and 92 eyes of 46 children without PHOMS (controls) who were assessed by disc enhanced-depth image spectral-domain (SD) optical coherence tomography (OCT). Univariable and multivariable logistic analyses were performed to evaluate risk factors associated with presence of PHOMS. Among the 66 children with PHOMS, 53 (80.3%) had bilateral and 13 (19.7%) had unilateral PHOMS. The mean age of the PHOMS group was 11.7 ± 2.6 years, and that of the control group was 11.4 ± 3.1 years. The mean spherical equivalent (SE) as determined by cycloplegic refraction was −3.13 ± 1.87 diopters (D) in the PHOMS group and −0.95 ± 2.65 D in the control group. Additionally, mean astigmatism was 0.67 ± 0.89 D and 0.88 ± 1.02 D in the PHOMS group and the control group, respectively. Mean disc size was 1,735 ± 153 µm in the PHOMS group and 1,741 ± 190 µm in the control group, while mean optic nerve head (ONH) tilt angle was 9.84 ± 5.38 degrees in the PHOMS group and 3.71 ± 4.41 degrees in the control group. SE and ONH tilt angle were significantly associated with PHOMS according to both univariable [odds ratio (OR): 1.59; p < 0.001 and OR: 1.35; p < 0.001, respectively] and multivariable (OR: 1.71; p = 0.001 and OR: 1.29; p = 0.001, respectively) logistic regression analyses. There was a significant correlation between SE and ONH tilt (r = −0.46; p < 0.001). In conclusion, PHOMS is associated with myopic shift in children, and optic disc tilt may be a mediator between myopia and PHOMS.

Novel biallelic splice-site BBS1 variants in Bardet-Biedle syndrome: a case report of the first Japanese patient

PURPOSE

To report the clinical and genetic features of a 9-year-old female Japanese patient with Bardet-Biedl syndrome (BBS).

METHODS

Genetic analysis using whole-exome sequencing (WES) was performed for the patient and her parents to identify disease-causing variants. Reverse transcriptase-polymerase chain reaction (RT-PCR) was performed to investigate the impact of splice-site variants. Comprehensive ophthalmic and systemic examinations, including electroretinography (ERG), were performed.

RESULTS

In the patient, WES identified novel compound heterozygous splice-site variants (c.124+2T>G and c.723+2T>G) in the BBS1 gene, and RT-PCR revealed skipping of exons 2 and 8 (p.N17AfsX56 and p.T198_K241del). Each parent had one of the variants. Ophthalmologically, the patient's decimal best-corrected visual acuity was 0.6 in the right eye and 0.4 in the left eye. Funduscopy revealed no apparent retinal degeneration or narrowed blood vessels in the periphery, but macular abnormalities were found on fundus autofluorescence imaging and optical coherence tomography images. Unexpectedly, non-recordable responses in rod ERG were found, with a non-recordable response of the right eye and an extremely reduced and delayed a-wave of the left eye in standard ERG, non-recordable responses in cone ERG, and extremely decreased responses in 30 Hz flicker ERG. Finally, the patient fulfilled four primary features of BBS diagnostic criteria: rod-cone dystrophy, polydactyly, central obesity, and learning disabilities, being diagnosed with BBS.

CONCLUSIONS

This is the first report of a BBS patient with biallelic splice-site BBS1 variants in the Japanese population. Disparity between funduscopic and ERG findings may be a feature of BBS1-associated rod-cone dystrophy.

Increased Subfoveal Choroidal Thickness and Retinal Structure Changes on Optical Coherence Tomography in Pediatric Alport Syndrome Patients

Objective

To evaluate optical coherence tomography (OCT) findings of pediatric Alport syndrome (AS) patients with no retinal pathology on fundus examination.

Materials and Methods

Twenty-one patients being followed up with the diagnosis of AS (Group 1) and 24 age- and sex-matched healthy volunteers (Group 2) were prospectively evaluated. All participants underwent standard ophthalmologic examination, retinal nerve fibre layer (RNFL) analysis, and horizontal and vertical scan macula enhanced depth imaging OCT (EDI-OCT). Statistical analysis of the data obtained in this study was performed with SPSS 15.0.

Results

Macula thickness was significantly decreased in the temporal quadrant in Group 1 compared to those of the control group (p=0.013). RNFL measurements revealed statistically significant thinning in the temporal, superior, inferotemporal, and inferonasal quadrants and in average thicknesses in cases with AS compared to the controls (p < 0.001, p < 0.001, p=0.022, p=0.016, p < 0.001, respectively). The mean subfoveal coronial thickness (SCT) was 362.2 ± 77.8 μm in Group 1 and 256,18 ± 71.7 μm in Group 2. There was a statistically significant difference between the two groups in terms of mean CT (p < 0.001).

Conclusion

OCT provides valuable information in identifying the structural changes and evaluation of ocular findings in patients with AS. Even if no pathological retinal findings were found in the clinical examination, structural changes in the OCT examination begin in early period of AS.

Retinal Nerve Fiber Layer Protrusion Associated with Tilted Optic Discs

SIGNIFICANCE

This study resulted in the identification of an optic nerve head (ONH) feature associated with tilted optic discs, which might potentially contribute to ONH pathologies. Knowledge of such findings will enhance clinical insights and drive future opportunities to understand disease processes related to tilted optic discs.

PURPOSE

The aim of this study was to identify novel retinal nerve fiber layer (RNFL) anomalies by evaluating tilted optic discs using optical coherence tomography. An observed retinal nerve fiber protrusion was further investigated for association with other morphological or functional parameters.

METHODS

A retrospective review of 400 randomly selected adult patients with ONH examinations was conducted in a referral-only, diagnostic imaging center. After excluding other ONH pathologies, 215 patients were enrolled and evaluated for optic disc tilt and/or torsion. Gross anatomical ONH features, including size and rim or parapapillary region elevation, were assessed with stereoscopic fundus photography. Optical coherence tomography provided detailed morphological information of individual retinal layers. Statistical analysis was applied to identify significant changes between individual patient cohorts.

RESULTS

A dome-shaped hyperreflective RNFL bulge, protruding into the neurosensory retina at the optic disc margins, was identified in 17 eyes with tilted optic discs. Available follow-up data were inconclusive regarding natural changes with this ONH feature. This RNFL herniation was significantly correlated with smaller than average optic disc size (P = .005), congenital disc tilt (P < .0001), and areas of rim or parapapillary elevation (P < .0001).

CONCLUSIONS

This study reports an RNFL protrusion associated with tilted optic discs, which has not previously been assessed as an independent ONH structure. The feature is predominantly related to congenital crowded, small optic discs and variable between patients. This study is an important first step to elucidate diagnostic capabilities of tilted disc morphological changes and understanding associated functional deficits.

MACULAR MICROSTRUCTURAL FEATURES IN CHILDREN WITH TILTED DISK SYNDROME EVALUATED BY SPECTRAL DOMAIN OPTICAL COHERENCE TOMOGRAPHY

PURPOSE

To assess macular microstructure in eyes with tilted disk syndrome (TDS) and determine the relationship between TDS foveal morphology and visual function.

METHODS

Twenty-six TDS eyes from 19 children (aged 5∼15 years) with a spherical equivalent refraction (SER) of -3.1 ± 1.3 diopter (D) and 28 control eyes from 14 children (aged 7∼12 years) with a SER of -3.0 ± 0.7 D were recruited. Horizontal and vertical optical coherence tomography scans through the fovea produced images that were segmented into eight intraretinal layers. Thicknesses of the total retina and each layer were measured at the foveal center and 12 other macular locations: 500 μm, 1,000 μm, and 1,500 μm along the horizontal and vertical meridians. The relationships between TDS best correct visual acuity (BCVA) and the presence of photoreceptor inner/outer segment (IS/OS) junction line, IS/OS foveal bulge, and cone outer segment tip (COST) line were evaluated.

RESULTS

The thickness of TDS central fovea, 218.94 ± 22.20 μm, was not significantly different from controls. The total retinal thickness in TDS eyes was thinner than controls at all peripheral locations (P < 0.05) except at 500 μm and 1,000 μm superiorly, and 1,500 μm temporally. Tilted disk syndrome intraretinal layer thicknesses in the nasal and inferior regions varied significantly from controls (P < 0.05). Only 80.7% and 23.1% of TDS eyes had a normal foveal bulge and continuous COST line, respectively, compared with 100% and 96.4% of controls. The BCVA of TDS eyes was similar whether or not the foveal bulge or COST line was abnormal.

CONCLUSION

Differences in intraretinal layer thickness may be correlated with defective vision.