Optic nerve head drusen

Optic nerve sheath diameter and axial length in patients with optic disc drusen: a cross-sectional study

AIM

Measuring the optic nerve sheath diameter (ONSD) and the anteroposterior axial length of the eye in patients with optic disc drusen (ODD).

METHODS

A total of 43 healthy volunteers and 41 patients with ODD were included in the study. The ONSD and axial length were measured in the posterior position using an ultrasound device (E-Z Scan AB5500 +) probe with a 10 MHz frequency. The ONSD was measured 3 mm behind the globe wall. Receiver operating characteristic (ROC) curve analysis was performed to determine patients with ODD using ONSD. Any p-value of < 0.05 was accepted to demonstrate significance.

RESULTS

The ONSD was significantly higher (5.2 mm and 4.8 mm, p = 0.006, respectively), and the axial length was shorter (21.82 ± 2.15 mm and 23.27 ± 1.96 mm, p = 0.002, respectively) in the ODD group. The spherical equivalent was more commonly seen as hypermetropic in the ODD group (1.00 [- 0.85 to 1.75]). In the ROC analysis to determine the ONSD value in ODD diagnosis, the area under the curve was 0.6754 (95% confidence interval 0.559-0.788, p = 0.006). ONSD cutoff of 5.70 mm had a sensitivity of 0.366 and a specificity of 0.907 to diagnose ODD.

CONCLUSION

In this study, the ONSD was significantly higher in the ODD group. The axial length was shorter in the ODD group. This study is the first in the literature to evaluate the ONSD in patients with optic disc drusen. Further studies are needed in this regard.

Unilateral buried optic nerve head drusen triggering central retinal vein occlusion in young – Discovering an eclipsed entity

Optic nerve head (ONH) drusen are acellular calcified concretions. Buried drusen manifests as pseudopapilledema. The compressive effects of ONH drusen can rarely precipitate central retinal vein occlusion (CRVO). The superimposition of pseudopapilledema on disc edema in CRVO poses a diagnostic dilemma. A 40-year-old female without systemic comorbidities presented with resolving CRVO. An exhaustive systemic workup revealed no abnormalities. Ultrasonography demonstrated buried ONH drusen. This unusual etiology must be considered in a young patient in the absence of systemic risk factors, persistence of "nasally conspicuous" disc elevation, and presence of peripapillary hemorrhages. Ultrasonography must be incorporated in the diagnostic armamentarium in a young patient with CRVO.

Optic Disc Drusen (ODD), an Often Misdiagnosed Disease: A Case Report

Optic disc drusen (ODD) are abnormal collections of protein and calcium that accumulate within the optic nerve. We report a case of a 17-year-old girl who presented to the Department of Ophthalmology at the Cheikh Khalifa International University Hospital, Casablanca, Morocco, with a decline in visual acuity, visual field deficiency, and color vision abnormalities. The patient was misdiagnosed and mistreated for optic neuritis given the presence of bilateral Stage III papilledema solely. After many months of diagnostic wandering, a fundus examination revealed a white atrophic papilla with calcified deposits grouped in a crown around the papillary excavation, suggesting papillary drusen. When the deposits are visible on ophthalmoscopy and manifest as an elevation and a blurring of the optic disc's margins, their diagnosis remains straightforward. However, their identification might be problematic when they are firmly lodged in the optic disc or with the presence of papilledema, leading to confusion with other differential diagnoses, particularly if the condition affects both eyes. The purpose of this case report is to increase neurologists' and ophthalmologists' knowledge of the incidence of drusen in order to prevent excessive biological and imaging investigation in addition to harmful effects from needless drugs.

Papilledema: A Review of the Pathophysiology, Imaging Findings, and Mimics

Increased intracranial pressure is the most common cause of papilledema. Multiple etiologies such as cerebral edema, hydrocephalus, space occupying lesions, infection, and idiopathic intracranial hypertension among others should be considered. Imaging plays a critical role in the detection of pathologies that can cause papilledema. MRI with contrast and CE-MRV, in particular, are key for the diagnosis of idiopathic intracranial hypertension. This review will focus in common and infrequent causes of papilledema, the role of imaging in patients with papilledema as well as its potential mimickers.

Visual field defects due to optic nerve drusen in Afro-Caribbean patients: A case series of 16 eyes

INTRODUCTION

Optic Nerve Head Drusen (ONHD) are very rare among black patients but may cause more severe visual defects in these patients. The goal of our study was to describe the frequency of visual field defects secondary to OND in Afro-Caribbean patients and study the characteristics of their physical examination, color vision and contrast sensitivity.

METHODS

We carried out a prospective study at the Martinique university medical center on patients of African descent with ONHD diagnosed on fundus examination and B-scan ultrasonography. All patients received a complete neuro-ophthalmological examination. The primary study endpoint was the frequency of visual field defects. Secondary study endpoints were the results of ETDRS visual acuity, Pelli-Robson contrast sensitivity chart, and 15 hue color vision test.

RESULTS

Sixteen eyes of 10 patients from 11 to 68 years of age were included. Forteen eyes (87%) had exposed ONHD. Eleven eyes (69%) showed a visual field defect: 9 eyes (69%) had an enlarged blind spot, and 9 eyes (69%) had an arcuate scotoma. 3 eyes (19%) had loss of ETDRS visual acuity, and 12 eyes (75%) showed loss of Pelli-Robson contrast sensitivity. Five eyes (31%) had an abnormal color vision test.

CONCLUSION

This is one of the largest case series of ONHD in Black patients. The frequency of visual field defects was high but comparable to that of studies in other ethnic groups. Larger comparative studies are necessary to confirm these results.

Is a virtual clinic model a safe and effective way for assessing patients referred with suspiciously blurred optic discs? The blurred disc clinic

BACKGROUND

There are increasing numbers of referrals to ophthalmology departments due to blurred optic disc margins. In light of this and the COVID-19 pandemic we aimed to assess whether these patients could be safely assessed without direct contact between the clinician and patient.

METHODS

We retrospectively reviewed the records of consecutive patients seen in our 'blurred disc clinic' between August 2018 and October 2019. We then presented anonymous information from their referral letter, their visual fields and optic nerve images to two consultant neuro-ophthalmologists blinded to the outcome of the face-to-face consultation. In the simulated virtual clinic, the two consultants were asked to choose an outcome for each patient from discharge, investigate or bring in for a face-to-face assessment.

RESULTS

Out of 133 patients seen in the blurred disc clinic, six (4.5%) were found to have papilloedema. All six were identified by both neuro-ophthalmologists as needing a face-to-face clinic consultation from the simulated virtual clinic. One hundred and twenty (90%) patients were discharged from the face-to-face clinic at the first consultation. The two neuro-ophthalmologists chose to discharge 114 (95%) and 99 (83%) of these respectively from the simulated virtual clinic. The virtual clinic would have potentially missed serious pathology in only one patient who had normal optic discs but reported diplopia at the previous face-to-face consultation.

CONCLUSIONS

A virtual clinic model is an effective way of screening for papilloedema in patients referred to the eye clinic with suspicious optic discs. Unrelated or incidental pathology may be missed in a virtual clinic.

The Relationship between Intraocular Pressure and Optic Nerve Structural and Functional Damage in Patients with Optic Nerve Head Drusen

The aim of this retrospective study was to evaluate if, in ocular normotensive patients, at the time of diagnosis of optic nerve head drusen (ONHD), perimetric mean deviation (PMD) on visual field (VF) examination and retinal nerve fibre layer (RNFL) thickness on optical coherence tomography correlated with intraocular pressure (IOP). There was a significant association between IOP and PMD (Spearman's rho = -0.863, p < .01) and between IOP and RNFL thickness (Spearman's rho = -0.630, p < .01). A higher IOP was associated with a greater functional loss in the VF and a reduction in the RNFL thickness. These results suggest that a clinical trial of IOP reduction should be considered in patients with ONHD to decrease the progression of optic nerve damage over time.

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.

Detection of Optic Disc Drusen in Children Using Ultrasound through the Lens and Avoiding the Lens-Point of Care Ultrasound Technique of Evaluation Revisited

AIM

To assess whether the detection rate of optic disc drusen (ODD) in children with swollen optic discs varies if the ultrasound scan (USS) is performed through the lens or avoiding the lens.

METHODS

Retrospective review of the ultrasound machine database for all patients who underwent USS for swollen discs in the department of pediatric ophthalmology, UPMC Children's Hospital of Pittsburgh. Only patients who had both fundus pictures and USS performed (through and avoiding the lens) were included in the study.

RESULTS

A total of 31 patients (62 eyes) were included in the study. USS detected ODD in 44% of eyes (27 of 62 eyes, 15 patients). In 82% of these eyes (22 of 27 eyes), the ODD were not detected initially when scanning was done through the lens but were only detected when scanning was performed avoiding the lens. Ten out of sixteen patients with no ODD on USS had another identifiable cause for disc elevation, including raised intracranial pressure and sleep apnea.

CONCLUSION

Ultrasound is a sensitive diagnostic tool for detecting ODD. The rate of detection of ODD is increased when USS is done avoiding the lens in children where the ODD are usually buried and not as calcified as those found in adults. Under such circumstances, the reduced echogenicity is absorbed by the absorbent pediatric lens, thus limiting the detection rates when scanning through the lens.

The swollen optic nerve: an approach to diagnosis and management

The differential diagnosis of swollen optic nerves differs according to whether the swelling is unilateral or bilateral, or whether visual function is normal or affected. Patients with a unilaterally swollen optic nerve and normal visual function most likely have optic nerve head drusen. Patients with abnormal visual function most likely have demyelinating optic neuritis or non-arteritic anterior ischaemic optic neuropathy. Patients with bilaterally swollen optic nerve heads and normal visual function most likely have papilloedema, and require neuroimaging followed by lumbar puncture. However, if their visual function is affected, the most likely causes are bilateral demyelinating optic neuritis, neuromyelitis optica spectrum disorder and anti-myelin oligodendrocyte glycoprotein optic neuritis: these patients require investigating with contrast-enhanced MRI of the orbits.

Transient monocular blindness: Vascular causes and differential diagnoses

Transient monocular blindness is an acute episode of ischemic origin in which one eye has profound visual loss, followed by full recovery within one hour. Transient monocular blindness most often occurs in the setting of retinal ischemia secondary to carotid embolism, but other mechanisms have been reported, including thrombosis (most often in the setting of giant cell arteritis), hemodynamic disorders (secondary to severe carotid stenosis), or vasospasm. Transient monocular blindness is considered a transient ischemic attack originating in the carotid arteries, and must be managed the same as transient ischemic attack involving the brain, in order to prevent a subsequent stroke.

Association of Optic Nerve Head Drusen with Best Vitelliform Macular Dystrophy: A Case Series

Purpose

To report the association of optic nerve head (ONH) drusen with Best vitelliform macular dystrophy (BVMD).

Methods

Chart review.

Patients

Five patients from 3 families.

Results

Multimodal imaging and ophthalmic examination demonstrated findings consistent with ONH drusen, in association with BVMD, in 5 patients.

Conclusion

We report the association of BVMD with ONH drusen in 5 patients. This combination has previously been reported only once. We recommend that patients with a diagnosis of BVMD undergo autofluorescence and ultrasound imaging of the optic nerve to help facilitate this diagnosis, as some ONH drusen can be buried.

Focal Capillary Dropout Associated With Optic Disc Drusen Using Optical Coherence Tomographic Angiography

Optic disc drusen may be a cause of visual field defects and visual loss. The mechanism by which this occurs is unclear. We report a patient who developed decreased vision in the right eye and was found to have a heavy burden of superficial optic disc drusen. Optical coherence tomography (OCT) confirmed focal retinal nerve fiber layer thinning that corresponded with the distribution of drusen. OCT angiography, with superficial laminar segmentation, showed focal capillary attenuation overlying the most prominent drusen. These findings demonstrate alterations in the superficial retinal capillary network associated with optic disc drusen.

Optic Disc Drusen and Family History of Glaucoma-Results of a Patient-directed Survey

PURPOSE

Prospective evaluation of family history (FH) of glaucoma and FH of optic disc drusen (ODD) in patients with sonographically confirmed ODD.

PATIENTS AND METHODS

A total of 87 patients with ODD interviewed all their first-degree and second-degree relatives using a detailed questionnaire on whether an ophthalmologist had diagnosed or excluded glaucoma or ocular hypertension (OH). Using a second questionnaire, 62 of these patients also provided information about ODD in their FH. Control groups for FH of glaucoma consisted of 2170 patients with glaucoma or OH evaluated with the same methods and identical questions for FH of glaucoma in a previous study, and of 176 healthy individuals without glaucoma or ODD who were interviewed on family history of glaucoma.

RESULTS

Glaucoma in FH was significantly more frequent in patients with ODD with an incidence of 20.7% compared with healthy controls with an incidence of 2.8%, and half as frequent as in glaucoma patients with an incidence of 40%. ODD in FH were found in 9.7% of patients with ODD.

CONCLUSIONS

As there is a high frequency of family history of glaucoma in patients with ODD, evaluation of FH of ODD and FH of glaucoma is essential in patients with ODD. Glaucoma in FH of ODD patients requires intraocular pressure monitoring and whenever deemed beneficial timely initiation of intraocular pressure-lowering therapy.

The Effect of a Decrease in Intraocular Pressure on Optic Nerve Function in Patients with Optic Nerve Drusen

PURPOSE

The aim of the study was to compare optic nerve function in eyes with brinzolamide-reduced intraocular pressure (IOP) and the fellow eyes of patients with optic disk drusen (ODD).

METHODS

The study comprised 34 patients with bilateral ODD but no signs of any other ocular disease. The eyes with more advanced optic neuropathy were selected for treatment with an IOP-lowering drug, carbonic anhydrase inhibitor (brinzolamide); the fellow eyes served as the control. Static perimetry, pattern electroretinography (PERG), pattern visual-evoked potentials (PVEP), and retinal nerve fiber layer (RNFL) thickness were analyzed. The observation period was 12 months.

RESULTS

The eyes with brinzolamide-reduced IOP exhibited a statistically significant decrease in the mean defect index of static visual field (p = 0.03), an increase in PERG N95 amplitude (from 2.94 to 4.41 µV; p = 0.0047), and RNFL thickness stabilization. A statistically significant decrease in RNFL thickness (from 83.21 to 79.85 µm; p = 0.0017) was found in the control eyes.

CONCLUSIONS

A decrease in IOP in eyes with ODD results in improvement of retinal ganglion cell function and delays the progression of optic neuropathy. PERG should be performed in patients with ODD as it is a sensitive test for monitoring optic neuropathy.

Detecting optic nerve head swelling on ultrasound and optical coherence tomography in children and young people: an observational study

BACKGROUND

Following high-profile cases, referrals for evaluation of 'suspicious optic discs' to eye clinics in the UK have sharply increased, asking ophthalmologists to reliably distinguish between true and pseudopapilloedema. Optic nerve sheath dilatation (ONSD) on ocular ultrasound (US) is considered a reliable sign of true papilloedema, but this test is not widely available. Recently, anterior bowing of Bruch's membrane (BM) and increased retinal nerve fibre layer thickness on optical coherence tomography (OCT) have emerged as indicators of intracranial hypertension, and OCT is widely available. We aimed to evaluate safety and efficacy of the diagnostic workup in our service, with particular emphasis of diagnostic reliability of US and OCT.

METHODS

Retrospective service evaluation/cohort study of children and young people younger than 16 years investigated for 'suspicious discs' over a 7-month period in 2016 at a single eye care provider in London, UK. 61 children and young people underwent clinical assessment, US scan and OCT.

RESULTS

Of 61 cases, 3 had intracranial pathology. At presentation, only one had ONSD on US and anterior bowing of BM on OCT. Increased nerve fibre layer thickness in at least one of three relevant sectors was observed in two cases. All three cases of intracranial pathology, however, had significant points in their presenting or medical history.

CONCLUSION

Ophthalmologists and optometrists must not rely on funduscopy and ocular imaging when assessing a child for possible intracranial disease; history and basic neurological assessment are critical in the diagnostic workup.

Enhanced Depth Imaging Optical Coherence Tomography of Optic Nerve Head Drusen: A Comparison of Cases with and without Visual Field Loss

PURPOSE

Enhanced depth imaging (EDI) spectral-domain optical coherence tomography (SD OCT) has been recognized as the most sensitive tool to diagnose optic nerve head drusen (ONHD). The relationship between OCT characteristics and visual loss has not been well documented. This study compares EDI SD OCT-determined morphologic characteristics of drusen in eyes with or without visual field (VF) defects.

DESIGN

Descriptive study of patients attending the neuro-ophthalmology service of Moorfields Eye Hospital between January 2013 and October 2014.

SUBJECTS

Patients with diagnosed ONHD and EDI SD OCT imaging of the optic nerve head.

METHODS

Eyes with and without VF defects were compared with regard to retinal nerve fiber layer (RNFL) thickness, drusen morphology, size, extent, visibility on funduscopy, ultrasound, and fundus autofluorescence.

MAIN OUTCOME MEASURES

Difference in OCT characteristics of ONHD between patients with or without VF defects.

RESULTS

Of 38 patients, 69 eyes with ONHD were included. Thirty-three eyes had a normal VF with average mean deviation (MD) -0.96 (±1.2) dB and pattern standard deviation (PSD) 1.6 (±0.3) dB (group I), and 36 eyes had VF defects with MD -13.7 (±10.4) dB and PSD 7.2 (±3.6) dB (group II). Mean global RNFL thickness was 62 (±20.9) μm in the latter group and 99.0 (±12.9) μm in group I. In group I, the predominant drusen type was peripapillary drusen, of variable size. In group II, most eyes had confluent (P < 0.02) and large (>500 μm; P < 0.003) drusen, and drusen were more commonly visible on funduscopy (P = 0.001), ultrasound (P = 0.013), and autofluorescence (P = 0.002). Differences between the 2 groups reached statistical significance in a clustered analysis. RNFL thinning and autofluorescence showed relative sparing of the temporal sector. Sixty-four percent of patients with a VF defect in 1 eye also had a VF defect in their fellow eye.

CONCLUSIONS

Drusen size and drusen type as classified by OCT morphologic characteristics are significantly different in patients with or without VF defects. Confluent, large, and autofluorescent drusen were more commonly found in patients with VF defects. These findings may assist in clarifying how drusen give rise to visual loss, which is currently not known.

Optic disk drusen in children

Optic disk drusen occur in 0.4% of children and consist of acellular intracellular and extracellular deposits that often become calcified over time. They are typically buried early in life and generally become superficial, and therefore visible, later in childhood, at the average age of 12 years. Their main clinical significance lies in the ability of optic disk drusen, particularly when buried, to simulate true optic disk edema. Misdiagnosing drusen as true disk edema may lead to an invasive and unnecessary workup for elevated intracranial pressure. Ancillary testing, including ultrasonography, fluorescein angiography, fundus autofluorescence, and optical coherence tomography, may aid in the correct diagnosis of optic disk drusen. Complications of optic disk drusen in children include visual field defects, hemorrhages, choroidal neovascular membrane, nonarteritic anterior ischemic optic neuropathy, and retinal vascular occlusions. Treatment options for these complications include ocular hypotensive agents for visual field defects and intravitreal anti-vascular endothelial growth factor agents for choroidal neovascular membranes. In most cases, however, children with optic disk drusen can be managed by observation with serial examinations and visual field testing once true optic disk edema has been excluded.

Anterior ischemic optic neuropathy in association with optic nervehead drusen

Optic nerve head drusen (ONHD) are incidental ophthalmologic finding in the optic nerve. Patients with ONHD are often asymptomatic, but sometimes present with transient visual obscuration's (TVO), the reported incidence of which is 8.6%. Optic nerve head drusen are of two types: Superficial; visible and deep. The deep-buried drusen mimic papilledema. Because of the varied presentation deep-buried drusen pose a diagnostic challenge to the ophthalmologists. In young patients, they are mistaken for papilledema as it is clinically difficult to detect a buried drusen in the optic nerve head, but are seen on the surface with aging as the retinal nerve fiber layer thins out. They are observed as pale yellow lesions more often located towards the poles. Clinical examination aided with diagnostic tests like computed tomography (CT) orbits and ultrasound B scan can help establish the diagnosis. Herein, we report a rare case of optic nerve head drusen in a young lady, who presented with loss of vision and clinical evaluation and investigations suggested ONHD with anterior ischemic optic neuropathy.

Imaging Methods in the Diagnosis of Optic Disc Drusen

Optic disc drusen (ODD) are benign congenital anomalies of the optic nerve characterized by calcified hyaline bodies. While superficial drusen can be diagnosed easily during fundus examination, detecting buried drusen requires the use of additional imaging methods such as B-scan ultrasonography (USG), fundus fluorescein angiography (FFA), computed tomography (CT) and fundus autofluorescence (FAF). ODD can be detected by USG with the presentation of highly reflective round structures. ODD appear as hyperautofluorescent areas on FAF and bright spots on CT scans. FFA can be helpful in differentiating ODD from true optic disc edema. Optic disc edema shows early hyperfluorescence due to diffuse leakage whereas ODD presents as well-defined hyperfluorescence in the late phase. In recent years, it has been reported that optical coherence tomography (OCT) examination has allowed more detailed evaluation of ODD and yielded useful findings for the differentiation of optic disc edema from ODD. In this review, the role of OCT in the diagnosis of ODD is discussed.

Optic Disc Drusen: Longitudinal Aspects, with Emphasis on Visual Field Constriction and Enlarged Blind Spot: A Retrospective Hospital-Based Clinical Series

Purpose

To examine long-term data on optic disc drusen (ODD) from an outpatient hospital series that indicated more cases with advanced visual field constriction than is apparent from other clinical reports. The underlying pathophysiology is discussed, also with regard to enlarged blind spot, which, in view of the small disc at risk, may seem a paradox.

Methods

This is an observational retrospective study on an eye clinic series (n = 49), focusing on visual acuity, kinetic/static perimetry, and longitudinal trends, to include the question of eventual visual incapacity.

Results

Forty-nine patients (32 female and 17 male; bilateral ODD in 45) aged 5-76 years (median age 29 years for both sexes) were included in the study. Observation time was 1-54 years, with serial data recorded over at least 3 years in 25 patients. Visual field defects were found in 32 patients, with ODD considered responsible for the visual field defects demonstrated. Advanced unilateral concentric constriction (for the largest Goldmann object) was recorded in 10 patients, and bilaterally in 2. With regard to nonexplanatory side diagnoses, 2 patients had pituitary adenoma, 1 had a cavernous sinus meningioma, and 1 had neurosurgery for an arachnoid cyst.

Conclusions

We found more cases of marked visual field constriction than reported in other clinical series. A few such cases appeared acute and vascular, but the main trend was clinically quiet over time. All 49 patients could manage visually in daily life.

Case report of optic disc drusen with simultaneous peripapillary subretinal hemorrhage and central retinal vein occlusion

A 52-year-old Chinese gentleman presented with right eye floaters and photopsia over one week. His visual acuities were 20/20 bilaterally. Posterior segment examination showed a right eye swollen optic disc and central retinal vein occlusion (CRVO) associated with an area of subretinal hemorrhage adjacent to the optic disc. Fundus fluorescein (FA) and indocyanine green angiographies (ICGA) of the right eye did not demonstrate choroidal neovascularization (CNV), polypoidal choroidal vasculopathy (PCV), or retinal ischemia. Ultrasound B-scan revealed optic disc drusen (ODD). In view of good vision and absence of CNV, he was managed conservatively with spontaneous resolution after two months. Commonly, ODD may directly compress and mechanically rupture subretinal vessels at the optic disc, resulting in peripapillary subretinal hemorrhage, as was likely the case in our patient. Mechanical impairment of peripapillary circulation also results in retinal ischemia and may trigger the development of choroidal neovascularization (CNV) and/or polypoidal choroidal vasculopathy (PCV), leading to subretinal haemorrhage. Compromise in central venous outflow with increased retinal central venous pressure from the direct mechanical effects of enlarging ODD results in central retinal vein occlusion (CRVO). Patients with subretinal hemorrhage and CRVO from ODD should be monitored closely for the development of potentially sight-threatening complications.

The role of orbital ultrasonography in distinguishing papilledema from pseudopapilledema

PURPOSE

To determine the sensitivity and specificity of orbital ultrasonography in distinguishing papilledema from pseudopapilledema in adult patients.

METHODS

The records of all adult patients referred to the neuro-ophthalmology service who underwent orbital ultrasonography for the evaluation of suspected papilledema were reviewed. The details of history, ophthalmologic examination, and results of ancillary testing including orbital ultrasonography, MRI, and lumbar puncture were recorded. Results of orbital ultrasonography were correlated with the final diagnosis of papilledema or pseudopapilledema on the basis of the clinical impression of the neuro-ophthalmologist. Ultrasound was considered positive when the optic nerve sheath diameter was ≥3.3 mm along with a positive 30° test.

RESULTS

The sensitivity of orbital ultrasonography for detection of papilledema was 90% (CI: 80.2-99.3%) and the specificity in detecting pseudopapilledema was 79% (CI: 67.7-90.7%).

CONCLUSIONS

Orbital ultrasonography is a rapid and noninvasive test that is highly sensitive, but less specific in differentiating papilledema from pseudopapilledema in adult patients, and can be useful in guiding further management of patients in whom the diagnosis is initially uncertain.

Pseudopapilledema and association with idiopathic intracranial hypertension

PURPOSE

Diagnosing idiopathic intracranial hypertension (IIH), or pseudotumor cerebri, can be challenging in children. Diagnosis is based on lumbar puncture, opening pressures, and appearance of the optic disk. Misdiagnosis of papilledema, a typical finding, may lead to unnecessary treatments and procedures. We report 52 children over a 6-year period to better identify the true incidence of pseudopapilledema and other factors that may confound the diagnosis of IIH.

METHODS

A retrospective chart review approved by the Institutional Review Board was performed. Fifty-two children under the age of 21 referred to us based on suspected IIH or papilledema from 2007 to 2013 are included in this study. Patients were assessed by a pediatric ophthalmologist and a neurosurgeon.

RESULTS

Fifty-two children were initially diagnosed with IIH and/or papilledema; 26 diagnoses were revised to pseudopapilledema after pediatric ophthalmological review. Out of those 26 patients with pseudopapilledema, 14 had undergone lumbar punctures, 19 had MRIs, 9 had CTs, and 12 were taking medications-these medications were discontinued upon revision of the diagnoses. The difference in the CSF opening pressure between children diagnosed with true IIH (32.7 cm H2O) and children diagnosed with pseudopapilledema (24.7 cm H2O) was statistically significant.

CONCLUSIONS

IIH diagnosis is heavily reliant on the appearance of the optic disk. Pediatric ophthalmological assessment is essential to carefully examine the optic disk and prevent further unnecessary investigation and treatments. Close communication between pediatricians, ophthalmologists, and neurosurgeons can avoid invasive procedures for children who do have pseudopapilledema, and not IIH or associated papilledema.

Visual field loss in optic disc drusen patients correlates with central retinal artery blood velocity patterns

PURPOSE

(1) To characterize the retrobulbar circulation in patients with optic disc drusen (ODD) using colour Doppler imaging; (2) to explore the differences in retrobulbar hemodynamics in patients with primary open-angle glaucoma (POAG).

METHODS

Retrospective analysis using three diagnostic groups: patients with ODD, age-matched healthy controls and age- and visual defect-matched patients with POAG. Subjects with history of ocular trauma or ocular diseases including vascular-related diseases were excluded. Kruskal-Wallis and Spearman's correlation tests were performed to compare and explore the correlations between the hemodynamic parameters and visual field damage.

RESULTS

Sixty patients were included and equally divided between the three groups. Patients with ODD had lower systolic and diastolic flow velocities in the central retinal artery (CRA) when compared to healthy individuals, but no difference was found with the glaucoma group (p < 0.005 versus healthy; p range 0.30-0.37 versus POAG). The systolic shift in flow patterns correlated with the extent of visual field defect in ODD patients (p < 0.001, r = -0.78, confidence interval: -0.43 to -0.92), but not in POAG (p = 0.73). Short ciliary arteries from ODD patients had lower mean systolic flow velocities when compared to both healthy individuals and patients with POAG (p < 0.01 versus healthy; p ≤ 0.04 versus POAG). The ophthalmic artery in ODD group had significantly higher mean blood velocities than in the POAG (p = 0.04), while showing a significant overlap in Doppler waveform variables to the control group (p range 0.08-0.97).

CONCLUSIONS

Similar to patients with glaucoma, individuals with ODD have low blood flow velocities in the vessels around the optic nerve head. Unlike patients with glaucoma, however, their CRA's blood flow velocity patterns correlate with the extent of the visual field defects.

Assessment of optic nerve head drusen using enhanced depth imaging and swept source optical coherence tomography

BACKGROUND

Optic nerve head drusen (ONHD) are calcific deposits buried or at the surface of the optic disc. Although ONHD may be associated with progressive visual field defects, the mechanism of drusen-related field loss is poorly understood. Methods for detecting and imaging disc drusen include B-scan ultrasonography, fundus autofluorescence, and optical coherence tomography (OCT). These modalities are useful for drusen detection but are limited by low resolution or poor penetration of deep structures. This review was designed to assess the potential role of new OCT technologies in imaging ONHD.

EVIDENCE ACQUISITION

Critical appraisal of published literature and comparison of new imaging devices to established technology.

RESULTS

The new imaging modalities of enhanced depth imaging optical coherence tomography (EDI-OCT) and swept source optical coherence tomography (SS-OCT) are able to provide unprecedented in vivo detail of ONHD. Using these devices it is now possible to quantify optic disc drusen dimensions and assess integrity of neighboring retinal structures, including the retinal nerve fiber layer.

CONCLUSIONS

EDI-OCT and SS-OCT have the potential to allow better detection of longitudinal changes in drusen and neural retina and improve our understanding of drusen-related visual field loss.

The association of Alagille syndrome and craniosynostosis

Alagille syndrome is associated with various ocular abnormalities, including pseudopapilledema or optic disk edema due to increased intracranial pressure. Several mechanisms have been proposed to explain the mechanism of intracranial hypertension in Alagille syndrome. Craniosynostosis is an unusual but significant cause of increased intracranial hypertension in Alagille syndrome. It has recently been demonstrated in animal models that Jagged1 gene in which mutations are responsible for Alagille syndrome may also take part in cranial suture formation. We report a child with Alagille syndrome and craniosynostosis who presented with pruritus, elevated liver enzymes, and suspected increased intracranial pressure.

Buried disc drusen have hypo-reflective appearance on SD-OCT

PURPOSE

Buried disc drusen are an important differential diagnosis for papilledema. Spectral domain optical coherence tomography (SD-OCT) affords clinicians with new non-invasive opportunities to probe below the surface of the optic nerve. Clinicians may use the knowledge of this appearance to rule out buried disc drusen in patients with irregular optic nerve borders or a bulging, hyperemic appearance.

METHODS

SD-OCTs were obtained in a patient with one surfacing disc druse, identifying the nature of the appearance of this disc druse and others in this and the contralateral eye when imaged with this technology. B-scan ultrasonography was used to confirm the presence of disc drusen. Additional scans in multiple patients with confirmed buried drusen were obtained for comparison.

RESULTS

Drusen appear as rounded hyporeflectant areas on SD-OCT, similar in appearance to blood vessels. They share the appearance of cysts but show a fine hyperreflective border anteriorly. These same discrete hyporeflective areas were found at various depths within optic nerve heads with confirmed buried disc drusen.

CONCLUSIONS

The hyporeflective appearance may not be anticipated by clinicians, as B-scans show calcified drusen as hyperreflective on echo. It is hypothesized that the hyporeflectant appearance of drusen is due to a constancy in refractive index through the druse, as OCT detects changes in optical reflectivity. Thus, drusen are likely dense and homogenous. SD-OCT may be more useful in those patients with buried disc drusen which are not calcified as B-scan often contributes little in such cases.

Bilateral optic disc drusen mimicking papilledema

Background

Optic disc drusen, which are calcified deposits that form anterior to the lamina cribrosa in the optic nerve, may mimic papilledema.

Case Report

We report herein three cases referred to us with suspicion of disc swelling and papilledema. Following ophthalmologic evaluation with B-scan ultrasound, red-free fundus photography, and computed tomography, the diagnosis of papilledema was excluded in all cases and optic disc drusen was diagnosed.

Conclusions

Clinical suspicion of optic disc drusen in cases presenting with swelling of the optic nerve head is important in order to avoid unnecessary interventions and anxiety. The reported cases highlight the commonly encountered clinical presentations and the practical aspects of diagnosis and management of optic disc drusen.

Snapshot hyperspectral retinal camera with the Image Mapping Spectrometer (IMS)

We present a snapshot hyperspectral retinal camera with the Image Mapping Spectrometer (IMS) for eye imaging applications. The resulting system is capable of simultaneously acquiring 48 spectral channel images in the range 470 nm-650 nm with frame rate at 5.2 fps. The spatial sampling of each measured spectral scene is 350 × 350 pixels. The advantages of this snapshot device are elimination of the eye motion artifacts and pixel misregistration problems in traditional scanning-based hyperspectral retinal cameras, and real-time imaging of oxygen saturation dynamics with sub-second temporal resolution. The spectral imaging performance is demonstrated in a human retinal imaging experiment in vivo. The absorption spectral signatures of oxy-hemoglobin and macular pigments were successfully acquired by using this device.

Bilateral optic nerve drusen and gliomas in Klippel-Trenaunay syndrome

Klippel-Trenaunay syndrome (KTS) consists of a vascular nevus involving an extremity, varicosities of that extremity, and hypertrophy of bone and soft tissue. When arteriovenous malformation is also present, it is called Klippel-Trenaunay-Weber syndrome (KTWS). Ophthalmic features of these syndromes include vascular anomalies of the orbit, iris, retina, choroid, and optic nerve. We report a case of a 16-year-old girl with KTS who was found to have bilateral optic nerve and chiasmal gliomas, optic disk drusen, and acquired myelination of the retinal nerve fiber layer. These findings have not been previously reported to be associated with KTS or KTWS.

Ischemic central retinal vein occlusion and neovascular glaucoma as a result of optic nerve head drusen

PURPOSE

The purpose of this study was to report a case of ischemic central retinal vein occlusion (CRVO) caused by optic nerve head drusen.

METHODS

Case report and review of the literature.

RESULTS

A healthy 13-year-old boy was diagnosed with bilateral optic nerve head drusen. Two years later, he developed an ischemic CRVO and secondary neovascular glaucoma. A full medical workup was negative. Despite treatment, his vision eventually declined to no light perception from a funnel detachment.

CONCLUSION

Nonischemic CRVO or venous stasis retinopathy is a well-known entity associated with optic nerve head drusen. The authors report a case of ischemic CRVO in a patient with no underlying risks for this other than the observed drusen. This report clearly shows that optic nerve drusen may not be entirely benign and that they can precipitate ischemic CRVO.

Optical coherence tomography/scanning laser ophthalmoscopy imaging of optic nerve head drusen

BACKGROUND AND OBJECTIVE

To evaluate optical coherence tomography/scanning laser ophthalmoscopy (OCT/SLO) imaging for optic nerve head drusen (ONHD).

PATIENTS AND METHODS

Nine consecutive eyes with ONHD were imaged. Each underwent visual field testing, 20-MHz B-scan ultrasonography, photography, and OCT/SLO imaging of the nerve head. Similar evaluation was performed on 12 matched, disease-free control eyes for comparison.

RESULTS

OCT/SLO imaging of ONHD demonstrated lucencies (100%), variable amounts of displacement, and thickening of the overlying nerve fiber layer, as well as disorganization of the adjacent retinal pigment epithelium (44%). Optic nerve head topography was measured (using horizontal and vertical electronic calipers). Mean disc diameter was 1.81 mm (range: 1.49 to 2.12 mm). All ONHD demonstrated anterior displacement of the base of the optic nerve cup (shallowing) compared to controls. The cup base was a mean +0.32 mm anterior to the retinal pigment epithelium for ONHD versus -0.23 mm for normal controls.

CONCLUSION

OCT/SLO revealed unique and clinically helpful views of ONHD.

Optic nerve head drusen: a case of false-positive papilledema discovered by ocular ultrasound in the emergency department

Case report

A 15-year-old female presented to the emergency department (ED) from her optometrists office for further evaluation of reported papilledema. The patient was otherwise asymptomatic. A CT scan was performed in the ED which showed calcification of the optic nerve. A bedside ultrasound was also performed which confirmed the presence of optic nerve calcification in both eyes. The patient was discharged with a diagnosis of optic nerve head drusen and instructed to follow- up with her ophthalmologist for continued monitoring of the drusen.

Discussion

Optic nerve drusen are generally benign lesions associated with pseudopapilledema which may be associated with peripheral field visual defects. Management for this condition in most cases consists of routine ophthalmologic monitoring. There is no definitive treatment for this entity.

An atypical case of optic disk drusen with nerve fiber layer thickening

We report an atypical case of optic disk drusen (ODD). A 12-year-old girl complained of blurred vision in both eyes. However, visual acuities in both eyes were 20/20. Fundus examination revealed blurring of the optic disk margins and elevation of the optic disk in both eyes. Initially it was considered that the diagnosis would be papilledema. However, neurologic examination revealed no pathology which would cause the visual field defect and disk elevation. Optical coherence tomography (OCT) scans showed hyperreflectance lesions on the disk and shadowing areas beneath the optic nerve head in both eyes. Orbital ultrasound and orbital and cranial tomography revealed protuberances with hyperechogenicity and calcification in both eyes. It was considered that these findings were consistent with ODD. Repeated visual field tests showed constricted peripheral field loss in both eyes. Using OCT software, peripapillary nerve fiber layer thickening in both eyes corresponded to visual field defects in the superior and inferior quadrants, in which drusen was detected. Despite the extensive literature, in cases of ODD with blurred margins, elevated disks, and visual field defects, the peripapillary nerve fiber layer may be increased due to nerve layer infarct in the area which has calcification.

Imaging of optic nerve head drusen: improvements with spectral domain optical coherence tomography

OBJECTIVE

To demonstrate a new algorithm that can determine the shape, location, and volume of optic nerve head drusen (ONHD), which were imaged with spectral domain optical coherence tomography (SDOCT).

METHODS

One exenteration patient and 4 glaucoma patients with bilateral ONHD were recruited from the Massachusetts Eye and Ear Infirmary and from a private practice office. Images were obtained using an experimental SDOCT system developed at the Wellman Center for Photomedicine, Massachusetts General Hospital. With axial resolutions of about 6 mum, SDOCT can obtain 2-dimensional images in 1/29 of a second, compared with commercially available time domain OCT instruments with 10 mum resolution images in 1.28 seconds. The volumes of ONHD were calculated with a new algorithm and were then correlated with visual field mean deviation.

RESULTS

SDOCT can display 2-dimensional images comparable with histology and 3-dimensional videos of ONHD. ONHD are signal-poor regions with high-signaled borders. Larger ONHD volumes are directly correlated with larger mean deviation absolute values on Humphrey visual field testing.

CONCLUSIONS

SDOCT is a potentially better technique for ONHD imaging and may improve the diagnosis and management of patients with both OHND and glaucoma.