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

Understanding pseudopapilledema on spectral domain optical coherence tomography

Purpose

Optic nerve head drusen (ONHD), peripapillary hyperreflective ovoid mass-like structures (PHOMS), and horizontal hyperreflective lines (HHL) are commonly seen in eyes with pseudopapilledema on enhanced depth imaging (EDI) spectral domain optical coherence tomography (SDOCT). The objective of this study is to assess the frequency of ONHD, PHOMS, and HHL on spectral domain OCT in the eyes diagnosed to have pseudopapilledema.

Methods

A retrospective case-control study included patients diagnosed as pseudopapilledema and had EDI SD OCT imaging of the optic nerve head (n = 48 eyes) and controls (n = 20 eyes). OCT scans through the optic nerve head were studied to diagnose ONHD, HHL, and PHOMS. One proportion z test was used to find the difference in proportions.

Results

Forty eight eyes of 27 subjects were studied. ONHD as described by the optic disc drusen Studies consortium was noted in 19 eyes (39.48%), P value-0.032, PHOMS in 31 eyes (64.6%), P value 0.043, HL in 19 eyes (39.48%), P value 0.032, and none of the normals had ONHD, PHOMS, and HHL.

Conclusions

PHOMS are more frequently seen than ONHD and HHL in eyes with pseudopapilledema.

Clinical Findings and Optical Coherence Tomography Measurements of Pediatric Patients with Papilledema and Pseudopapilledema

Objectives

To compare the clinical findings and multimodal imaging of pediatric patients diagnosed with papilledema and pseudopapilledema with those of healthy individuals.

Materials and Methods

Ninety children (<18 years of age) referred for suspected papilledema were included in this study. All patients underwent optical coherence tomography (OCT) imaging and were compared with normal control subjects.

Results

Fifty-eight children diagnosed with pseudopapilledema, 32 children with mild-to-moderate papilledema, and 40 controls were evaluated. The average and all quadrants of retinal nerve fiber layer (RNFL) thickness were significantly higher in the papilledema group than in the pseudopapilledema and control groups (p<0.001). Bruch's membrane opening (BMO) measurements were similar in both groups (p>0.05). The average, nasal, and temporal RNFL thicknesses were significantly higher in the pseudopapilledema group compared with the controls (p<0.001). Area under the receiver operating characteristic (ROC) curve showed high diagnostic ability for RNFL thickness in all quadrants to differentiate papilledema from pseudopapilledema (p<0.001). In the pseudopapilledema group, average, temporal, and inferior RNFL thickness and BMO measurements were significantly higher in eyes with optic nerve head drusen (n=28) compared with those without drusen (n=88) (p=0.035, p=0.022, p=0.040 and, p=0.047 respectively).

Conclusion

Papilledema and pseudopapilledema show great differences in evaluation, follow-up, and prognosis. Using non-invasive methods such as newly developed OCT techniques in differential diagnosis can relieve patients with pseudopapilledema from the stress and financial burden of expensive, extensive, and invasive procedures.

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.

Optic disc drusen in patients diagnosed with normal tension glaucoma

PURPOSE

To investigate the prevalence of optic disc drusen (ODD) and optic nerve head (ONH) morphology in patients diagnosed with normal tension glaucoma (NTG).

METHODS

In this prospective cross-sectional study, we included patients diagnosed with NTG from two glaucoma units. In both eyes, dense enhanced depth imaging optical coherence tomography volume scans of the ONH by means of standardized scanning guidelines were performed to examine for presence of ODD, and radial ONH scans were used for investigating parameters such as scleral canal diameter, cup/disc ratio and cup depth.

RESULTS

We found ODD in 7 (3.6%) of 195 eyes, in 6 (6.1%) out of 98 patients diagnosed with NTG. The ODD were not ophthalmoscopically visible in five out of six patients. Eyes with ODD had lower cup/disc ratio, 0.44 ± 0.4 (p = 0.040), and less-prominent cup depth, 236.6 ± 204.4 μm (p = 0.041) compared to eyes without ODD, 0.81 ± 0.2 and 437.8 ± 139.1 μm, respectively. We found no significant difference in scleral canal diameter between the eyes without (1602.8 ± 193 μm) and those with ODD (1492 ± 123.4 μm, p = 0.057).

CONCLUSION

The prevalence of ODD in patients diagnosed with NTG is substantially higher than in the background population. A low cup/disc ratio correlates with ODD presence. Therefore, due to the challenges associated with NTG diagnosis, we recommend examining the deep layers of the ONH in NTG patients with a cup/disc ratio lower than 0.5 to avoid misdiagnosing ODD as NTG.

Short-term progression of optic disc and macular changes in optic nerve head drusen

PURPOSE

To quantify in patients with optic nerve head drusen (ONHD)changes after 1-year observation in: (i) optic disc and (ii) macular optical coherence tomography (OCT) parameters and (iii) the effect of age at enrolment in the study.

DESIGN

Prospective, cross-sectional observational study using Spectral Domain-OCT (Copernicus; OPTOPOL Technology S.A., Zawiercie, Poland) imaging was carried out in 35 patients with ONHD (age-42.8 ± 19.9 years; males = 15; females = 20) at baseline and after 12 months follow-up.

RESULTS

Patients with ONHD had significant thinning of the surface nerve fibre layer in the central (p = 0.03), superior (p = 0.05) and inferior (p = 0.04) areas; mean ppRNFL thinning (p = 0.0 4) and ppRNFL thinning in the nasal segment (p = 0.028). Retinal thinning in the central (p = 0.001), inner (p = 0.01) and outer (p = 0.002) temporal, outer superior (p = 0.03) and inferior (p = 0.02) areas; borderline ganglion cell layer thinning (p = 0.051) and outer nuclear layer (p = 0.03) thinning in the central retina and outer segment layer thinning nasally (p = 0.01) between the first and the second visit in macula. Correlation of the difference in optic disc and macular parameters with the age at enrolment did not reveal any significance.

CONCLUSIONS

Statistically detectable thinning of the optic nerve and macula structures occurred already after 12 months. The proximity of optic nerve changes to the vascular arcades can possibly be explained by involvement of retinal vessels in the pathophysiology of ONHD.

Detection of superficial and buried optic disc drusen with swept-source optical coherence tomography

Background

To detect the superficial and buried optic disc drusen (ODD) with swept-source optical coherence tomography (SS-OCT).

Methods

Retrospective cross-sectional study. Twenty patients (age 18–74 years) diagnosed with ODD via B-scan ultrasonography were analysed. All patients underwent color fundus photography (CFP), B-scan ultrasonography, fundus autofluorescence (FAF), and SS-OCT. We defined each hyporeflective signal mass of SS-OCT as an ODD, recorded its location and relationship with Bruch’s membrane opening (BMO), and other ophthalmic imaging characteristics.

Results

Twenty (33 eyes) patients had 54 ODDs in all, except one eye did not show abnormal optic disc findings on SS-OCT. We classified ODD into three categories: ODD above BMO, ODD across BMO, and ODD below BMO. The ODDs across BMO were the largest, followed by ODDs below BMO, and those above BMO. The location of the ODDs: One (1.9%) was in the border tissue of Elschnig, 6 (11.1%) might span across the lamina cribrosa, 16 (29.6%) were above BMO located in the neuroepithelial layer, 9 (16.7%) spanned across BMO located near the center of the optic disc, 18 (33.3%) were below BMO located near the center of the optic disc, 4 (7.4%) were below BMO located within the optic disc rim. When the anterior margin was ≥ 100 μm from the BMO, clear autofluorescence could be seen.

Conclusion

Multimodal imaging provided a deeper understanding of ODD. SS-OCT illustrated more details about the relationship between the posterior surface of ODD, BMO and the lamina cribrosa.

Enhanced depth imaging optical coherence tomography of the optic nerve head improves correct diagnosis in glaucoma suspects without glaucomatous optic disc morphology

An 83-year-old woman with a long history of glaucoma and optic disc drusen (ODD) was referred for neuro-ophthalmological second opinion. The patient had been treated for decades with bilateral intraocular pressure (IOP)-lowering eye drops, laser trabeculoplasty and trabeculectomy and had severe, bilateral loss of visual fields and retinal nerve fibre layer (RNFL) thinning on optical coherence tomography (OCT) despite IOP that never exceeded 24 mm Hg. On ophthalmoscopy, only a single ODD was visible in the left eye and no optic disc cupping was apparent in either eye. Enhanced depth imaging OCT (EDI-OCT) of the optic nerve head revealed bilateral multiple, large, deep ODD, which in itself could easily explain the visual field loss and RNFL thinning of this patient. Optic nerve head examination using EDI-OCT is highly recommended for patients with a history of glaucoma but without optic nerve head cupping to avoid a potential misdiagnosis with consequent unnecessary treatment.

Enhanced Depth Imaging Optical Coherence Tomography Technology Reveals a Significant Association Between Optic Nerve Drusen Anterior Displacement and Retinal Nerve Fiber Layer Thinning Over Time

BACKGROUND

Optic disc drusen (ODD) are a dynamic phenomenon, and their appearance, size, and relative location may change. The purpose of this study is to evaluate and quantify the longitudinal changes of buried ODD with enhanced depth imaging (EDI) optical coherence tomography (OCT) over time.

METHODS

ODD were analyzed with Spectralis OCT (Heidelberg Engineering, Heidelberg, Germany) and EDI technology. The peripapillary retinal nerve fiber layer (RNFL) thickness was also measured. The size and depth of ODD were compared between the baseline and study visit (at least 2 years of follow-up), and the changes were correlated with mean RNFL thickness. The repeatability, coefficient of variation, and cutoff values for size and depth on EDI-OCT were calculated.

RESULTS

Of 21 previously identified patients with ODD, only 12 patients (21 eyes) met the most recent diagnostic criteria according to the ODD Studies Consortium recommendations for using OCT-EDI technology. The 21 eyes were reanalyzed after a mean period of 44.7 ± 13.2 months (range: 24-71 months). Overall, 132 ODD were evaluated with a mean of 6.1 ± 2.5 ODD per eye and 1.9 ± 1.1 ODD per scan. Overall, we found a significant forward movement of the drusen between visits (P = 0.01). Most drusen (67.4%) moved anteriorly, and in approximately one-third (35.6%), this displacement exceeded the cutoff value (64.28 µm). Furthermore, we found a significant correlation between ODD shallowing and RNFL thinning during the follow-up (P ≤ 0.03; R ≥ 0.370). We did not find any significant changes in size measurements (P = 0.10) over time.

CONCLUSIONS

In approximately one-third of buried ODD, a significant anterior movement occurred over 2 years of follow-up, and this movement was associated with significant RNFL thinning. By contrast, no significant change was detected in the size of the buried ODD.

Utility of Ultrasound and Optical Coherence Tomography in Differentiating Between Papilledema and Pseudopapilledema in Children

BACKGROUND

Differentiating between papilledema and pseudopapilledema in children presenting with mild-to-moderate optic nerve head elevation is challenging. This study sought to determine which B-scan ultrasonography (BSUS) and optical coherence tomography (OCT) features, individually or in combination, are best able to differentiate between papilledema and pseudopapilledema in children.

METHODS

Children presenting with optic nerve head elevation of unknown etiology were eligible if they underwent BSUS and OCT performed by the same investigator. The absolute optic nerve sheath diameter (in millimeter) along with the presence/absence of a hyperreflective nodule(s) at the optic nerve head (indicative of druse) from BSUS was determined. The average circumpapillary retinal nerve fiber layer (cpRNFL), diameter of Bruch membrane opening, maximum papillary height, and the presence/absence of hyper-/hyporeflective lesions at the optic nerve head were calculated. Sensitivity and specificity were calculated to evaluate which BSUS and OCT imaging features, individually and in combination, accurately classified children as having papilledema vs pseudopapilledema.

RESULTS

One hundred eighty-one eyes from 94 children (mean age, 11.0 years; range, 3.2-17.9) were included; 36 eyes with papilledema and 145 eyes with pseudopapilledema. Among BSUS features, optic nerve sheath widening (>4.5 mm) demonstrated the best sensitivity (86%; 95% confidence interval [CI], 64%-96%) and specificity (88%; 95% CI, 79%-94%) for papilledema. Among OCT measures, cpRNFL thickness of ≥140 µm demonstrated the best sensitivity (83%; 95% CI, 66%-93%) and specificity (76%; 95% CI, 66%-84%) to identify papilledema. The presence of both optic nerve sheath widening (>4.5 mm) and cpRNFL thickness of ≥140 µm reduced the sensitivity (72%; 95% CI, 52%-86%) but increased specificity (95%; 95% CI, 88%-98%).

CONCLUSION

BSUS (optic nerve sheath widening [>4.5 mm]) and OCT (cpRNFL thickness ≥140 µm), individually and collectively, have good diagnostic accuracy for differentiating between papilledema and pseudopapilledema. The presence of druse does not exclude the diagnosis of papilledema.

Recent advances and future directions on the use of optical coherence tomography in neuro-ophthalmology

Optical coherence tomography (OCT) is a noninvasive imaging technique used to qualitatively and quantitatively analyze various layers of the retina. OCT of the retinal nerve fiber layer (RNFL) and ganglion cell-inner plexiform layer (GCIPL) is particularly useful in neuro-ophthalmology for the evaluation of patients with optic neuropathies and retrochiasmal visual pathway disorders. OCT allows for an objective quantification of edema and atrophy of the RNFL and GCIPL, which may be evident before obvious clinical signs and visual dysfunction develop. Enhanced depth imaging OCT allows for visualization of deep structures of the optic nerve and has emerged as the gold standard for the detection of optic disc drusen. In the evaluation of compressive optic neuropathies, OCT RNFL and GCIPL thicknesses have been established as the most important visual prognostic factor. There is increasing evidence that inclusion of OCT as part of the diagnostic criteria for multiple sclerosis (MS) increases its sensitivity. Moreover, OCT of the RNFL and GCIPL may be helpful in the early detection and monitoring the treatment of conditions such as MS and Alzheimer's disease. OCT is an important aspect of the neuro-ophthalmologic assessment and its use is likely to increase moving forward.

Optic disc drusen: a systematic review : Up-to-date and future perspective

BACKGROUND

Optic disc drusen (ODD) are acellular deposits in the prelaminar optic nerve head. The most accredited theory is that they are secondary to abnormalities in axonal metabolism and degeneration, but the pathogenesis is not clear to date.

CLINICAL MANIFESTATION

Although ODD are often considered a benign condition, the great majority of patients with ODD show visual field defects and are at higher risk for developing anterior ischemic optic neuropathy. ODD are classified as superficial or buried, with the latter being often misdiagnosed as papilledema with optic nerve head swelling, leading to an unnecessary investigation for causes of increased intracranial pressure.

AIM

The recent technological improvements in OCT imaging which allowed an earlier and more certain diagnosis even of the smallest ODD, renovated the interest around this pathology. However, an updated systematic review is still missing. Therefore, the aim of this work is to provide a concise yet comprehensive overview of the current state of art, focusing on pathophysiology, clinical presentation, diagnostic methods, treatment modalities and potential future perspectives of this condition.

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

BACKGROUND

Making an accurate diagnosis of optic disc drusen (ODD) is important as part of the work-up for possible life-threatening optic disc edema. It also is important to follow the slowly progressive visual field defects many patients with ODD experience. The introduction of enhanced depth imaging optical coherence tomography (EDI-OCT) has improved the visualization of more deeply buried ODD. There is, however, no consensus regarding the diagnosis of ODD using OCT. The purpose of this study was to develop a consensus recommendation for diagnosing ODD using OCT.

METHODS

The members of the Optic Disc Drusen Studies (ODDS) Consortium are either fellowship trained neuro-ophthalmologists with an interest in ODD, or researchers with an interest in ODD. Four standardization steps were performed by the consortium members with a focus on both image acquisition and diagnosis of ODD.

RESULTS

Based on prior knowledge and experiences from the standardization steps, the ODDS Consortium reached a consensus regarding OCT acquisition and diagnosis of ODD. The recommendations from the ODDS Consortium include scanning protocol, data selection, data analysis, and nomenclature.

CONCLUSIONS

The ODDS Consortium recommendations are important in the process of establishing a reliable and consistent diagnosis of ODD using OCT for both clinicians and researchers.

Enhanced Depth Imaging Optical Coherence Tomography of Optic Nerve Head Drusen in Children

BACKGROUND

To assess the utility of enhanced depth imaging optical coherence tomography (EDI-OCT), compared with other conventional imaging modalities, for detecting and characterizing optic nerve head drusen (ONHD) in children.

METHODS

We report a retrospective cross-sectional case series of consecutive pediatric patients (age ≤16 years) with ONHD confirmed using B-scan ultrasonography. All eyes were evaluated using spectral-domain OCT of the optic nerve head in conventional (non-EDI) and EDI modes, fundus autofluorescence (FAF), and standard automated perimetry. Detection rates and the capacity to characterize ONHD were compared between EDI-OCT, non-EDI-OCT, and FAF.

RESULTS

Twenty-eight eyes of 15 patients (mean age 11 years; 60% female) were identified with definite ONHD that were confirmed by B-scan ultrasound. Among the technologies, EDI-OCT, non-EDI-OCT, FAF, and automated perimetry had findings consistent with ONHD in 24, 21, 18, and 4 eyes, respectively. EDI-OCT had a significantly better detection capability (86% of eyes) compared with FAF (P = 0.04) but not with non-EDI-OCT (P = 0.15). Similar to results previously reported in adult patients, EDI-OCT detected ONHD at different levels of depth; most were located anterior to the lamina cribrosa. ONHD detected by EDI-OCT appeared as hypo-reflective ovoid regions bordered by hyper-reflective material or as isolated hyper-reflective bands without a hypo-reflective core. The mean greatest diameter of ONHD seen on EDI-OCT was 449.7 (SD ±114.1) μm.

CONCLUSIONS

EDI-OCT detects ONHD in most eyes identified as having drusen on B-scan ultrasonography. This technique has the potential to be an effective alternative first-line diagnostic and monitoring tool for ONHD, particularly for detecting buried drusen in children.

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

BACKGROUND

Optic disc drusen (ODD) are seen in up to 2.4% of the general population, but the etiology and pathophysiology of the condition is still unknown. The purpose of this study was to determine the prevalence of ODD in a population-based child cohort and to determine if scleral canal diameter and fetal birth and pubertal parameters are associated with the presence of ODD.

METHODS

This observational, longitudinal population-based birth cohort study, with a nested case-control, included 1,406 children. Eye examinations were performed when the children were between 11 and 12 years of age. Assessment was performed of optical coherence tomography (OCT) scans from 1,304 children with gradable enhanced depth imaging scans of the optic disc.

RESULTS

ODD in one or both eyes were found in 13 (1.0%) of all children. All but one of the cases were found in children with scleral canal diameter in the lowest quartile (1,182-1,399 μm) in the nested case-control study. Children with ODD had a mean disc diameter of 1,339 μm (interquartile range, 30 μm), whereas it was 1,508 μm (interquartile range, 196 μm) in the 130 controls without ODD (P < 0.001). No differences in sex, birth weight, refractive error, and Tanner stages (of puberty) were found between children with and without ODD.

CONCLUSIONS

The prevalence of ODD was 1% in a large child cohort examined by OCT. ODD was found only in eyes with a narrow scleral canal, which is consistent with the hypothesis that ODD might arise as a consequence of retinal nerve fiber congestion in the scleral canal.

Optic Nerve Head Drusen: An Update

Optic nerve head drusen are benign acellular calcium concretions that usually form early in life, just anterior to the lamina cribrosa. Improving imaging using optical coherence tomography suggests they are common and may be present in many clinically normal discs. These drusen may change in appearance in early life, but are generally stable in adulthood, and may be associated with visual field defects, anterior ischaemic optic neuropathy, or rarer complications. Based on long-term clinical data and optical coherence tomography, we propose a refined hypothesis as to the cause of optic disc drusen. Here we summarise recent findings and suggest future studies to better understand the forces involved.

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

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

The Role of Optical Coherence Tomography in Differentiating Optic Disc Drusen from Optic Disc Edema

An elevated optic nerve head can be an ominous sign, sometimes signifying an underlying basis for raised intracranial pressure. Alternatively, patients may harbor a different mechanism for this optic nerve head appearance, including optic disc drusen (ODD), which does not confer any life-threatening implications. It is important to refine the approach to distinguishing ODD from papilledema because this is a relatively common, and important, conundrum encountered in clinical practice. Optical coherence tomography (OCT) is a noninvasive, readily accessible, and cost-effective ocular imaging technique that can improve the diagnostic accuracy for detecting ODD; or, instead, increase the index of suspicion for papilledema, thus prompting additional investigations needed to identify (or exclude) potential causes of raised intracranial pressure. In this review, we will discuss the value of OCT in the diagnostic approach to cases of mild optic disc elevation, with acknowledgment of the potential pearls and pitfalls of this imaging technology. In particular, we will emphasize the helpful role OCT can play in differentiating cases of ODD from mild papilledema in the context of idiopathic intracranial hypertension (IIH).

Factors associated with visual field defects of optic disc drusen

Purpose

To investigate the prevalence and risk factors for visual field defect in patients with optic disc drusen (ODD).

Methods

We assessed the visual field status of patients with ODD whose diagnosis were confirmed by spectral-domain optical coherence tomography (SD-OCT). Visual field defects were classified as normal, enlarged blind spot, or other defects. ODD were classified into either type 1 (without hyperreflective border and heterogenic internal reflectance) or type 2 (with hyperreflective border and lower internal reflectance). The prevalence and risk factors for each visual field defect was analyzed using logistic regression analysis and classification and regression tree (CART) modeling.

Results

Of the 40 eyes with ODD, 33 (83%) eyes were categorized as type 1 and 7 (17%) eyes were categorized as type 2 ODD. Regarding the visual field defects, 19 (48%) eyes showed normal visual field, 11 (28%) eyes showed enlarged blind spot, and 9 (24%) eyes showed other defects. The latter was more frequent in type 2 ODD (P = 0.001). Logistic regression analysis revealed that the factor associated with other defects was the thinning of the average retinal nerve fiber layer (RNFL) (per 10 μm decrease, OR = 3.436, P = 0.004), and the factor associated with enlarged blind spot was the height of ODD (per 100 μm increase, OR = 3.956, P = 0.023). CART modeling revealed that the average RNFL thickness lesser than 85.5 μm, and then the ODD height larger than 348 μm were the best split-up factors for predicting the type of visual field defects.

Conclusions

In this study, one-quarter of ODD patients showed abnormal visual field defect other than enlarged blind spot. These other visual field defects appeared to be associated with the axonal loss in the eyes with type 2 ODD.

Volumetric Measurement of Optic Nerve Head Drusen Using Swept-Source Optical Coherence Tomography

PURPOSE

To describe new software tools for quantifying optic nerve head drusen volume using 3-dimensional (3D) swept-source optical coherence tomography (SS-OCT) volumetric scans.

MATERIALS AND METHODS

SS-OCT was used to acquire raster volume scans of 8 eyes of 4 patients with bilateral optic nerve head drusen. The scans were manually segmented by 3 graders to identify the drusen borders, and thereafter total drusen volumes were calculated. Linear regression was performed to study the relationships between drusen volume, retinal nerve fiber layer thickness, and Humphrey visual field mean deviation.

RESULTS

In the 8 study eyes, drusen volumes ranged between 0.24 to 1.05 mm. Visual field mean deviation decreased by ∼20 dB per cubic millimeter increase in drusen volume, and the coefficient of correlation of the linear regression was 0.92. In this small patient series, visual field defects were detected when drusen volume was larger than about 0.2 mm.

CONCLUSIONS

Software tools have been developed to quantify the size of OHND using SS-OCT volume scans.

Differentiation between optic disc drusen and optic disc oedema using fundus photography

PURPOSE

To describe a funduscopic sign that can be used to differentiate between optic disc drusen (ODD) and optic disc oedema (ODE).

METHODS

A total of 73 eyes from 73 consecutive subjects with disc margin blurring who had been evaluated using spectral-domain optical coherence tomography (SD-OCT) were included. Final diagnosis was made by SD-OCT; ODD was defined by direct visualization of ODD, while ODE was defined by documentation of retinal nerve fibre layer oedema (nasal retinal nerve fibre layer thickness >78.0 μm). Peripapillary retina was selected as a two-disc-diameter-sized square image from the fundus photograph. Using MATLAB software, colour photographs were converted to indexed image of eight colours. Presence of a smooth contour strip between the nasal disc margin and juxtapapillary retina was defined as a halo. Whether the halo could predict the ODD was analysed retrospectively.

RESULTS

The halo sign was detected in 45 eyes (100%) with ODD including one eye with both ODD and ODE. No eyes with ODE alone showed the halo sign. The halo sign implied the presence of ODD (Cohen's kappa = 1.000, p < 0.001) and the absence of ODE (Cohen's kappa = 0.971, p < 0.001). The halo sign showed a good interobserver reliability [ICC (2, 1) = 0.944, 95% confidence interval 0.912-0.964]. SD-OCT images showed that halos represented retinal elevations above ODD.

CONCLUSIONS

In the patients with blurred disc margin, the presence of a halo strongly suggested underlying ODD rather than ODE.

Optic Nerve Head Drusen Prevalence and Associated Factors in Clinically Normal Subjects Measured Using Optical Coherence Tomography

OBJECTIVE

To investigate the prevalence of optic nerve head drusen (ONHD) in clinically normal subjects using enhanced depth imaging (EDI) optical coherence tomography (OCT) and to evaluate associated factors.

DESIGN

Prospective, cross-sectional, observational study.

PARTICIPANTS

Total of 130 clinically normal subjects.

METHODS

Serial horizontal and vertical EDI OCT B-scans (interval between scans, ∼30 μm) of the optic nerve head (ONH) were obtained in both eyes of clinically normal subjects. Signs of ONHD were defined as horizontal hyperreflective bands perpendicular to the OCT beam with or without a signal-poor core. The minimum length of isolated hyperreflective bands was determined based on analysis of 34 eyes with clinically definite ONHD. Age, gender, ONH diameter, and axial length were obtained from participants.

MAIN OUTCOME MEASURES

Prevalence of ONHD in clinically normal subjects and its association with age, gender, ONH diameter, and axial length.

RESULTS

Based on the measurements of 94 isolated hyperreflective bands in the 34 eyes with clinically definite ONHD, the minimum length of isolated hyperreflective ONHD bands in clinically normal subjects was set as 45 μm (mean minus 2 standard deviations). Among 260 clinically normal eyes (130 subjects; 68 women; mean age, 40±17 years), EDI OCT was positive for horizontal hyperreflective ONHD bands in 28 eyes (10.8%) of 19 subjects (14.6%). Of these 28 eyes, 25 eyes (9.6% of total 260 eyes) of 16 subjects (12.3% of total 130 subjects) showed isolated hyperreflective bands with no signal-poor core, and 3 eyes (1.2% of total 260 eyes) of 3 subjects (2.3% of total 130 subjects) showed a signal-poor core surrounded by hyperreflective bands. No significant differences were found in mean age (44 vs. 39 years; P = 0.121) or gender distribution (56% vs. 52% female; P = 0.766) between clinically normal subjects with hyperreflective ONHD bands and those without. Logistic regression analysis showed that a decrease in ONH diameter by 100 μm and axial length by 1 mm increased the odds of ONHD presence by 1.5-fold (odds ratio [OR] = 1.56 [confidence interval (CI), 1.22-2.00]; P < 0.001) and 2-fold (OR = 2.00 [CI, 1.15-3.49]; P = 0.015), respectively.

CONCLUSIONS

Subclinical ONHD may be more prevalent than previously believed. Significant associations of subclinical ONHD with smaller ONH and shorter axial length were found.

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.

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.

Optic disc drusen associated with optic nerve tumors

PURPOSE

To propose a theory based on clinical observation, namely, whether axonal distress induced by optic nerve tumors could be a triggering factor for optic disc drusen (ODD) formation.

CASE REPORTS

A 28-year-old woman with ODD and optic disc melanocytoma, a 53-year-old woman with ODD and optic nerve meningioma, and a 29-year-old woman with ODD and optic nerve glioma underwent comprehensive ophthalmologic examinations including spectral-domain optical coherence tomography, swept-source optical coherence tomography, visual field tests, color vision tests, and complete neurologic examinations including brain magnetic resonance imaging. In two cases, unilateral ODD existed on the same side of optic nerve tumors. In the bilateral case, the nerve that contained the tumor had ODD that were located more deeply and on both nasal and temporal sides of the optic nerve compared with the contralateral eye. In two cases, optic disc edema (ODE) was also present, and ODD persisted after ODE resolved.

CONCLUSIONS

Optic nerve tumors can trigger the formation of ODD, which suggests that ODD pathogenesis involves axonal flow distress in the optic nerve. The presence of asymmetric ODD and ODE may indicate the presence of an optic nerve tumor.

Hemorrhagic complications of optic nerve head drusen on spectral domain optical coherence tomography

PURPOSE

To describe the clinical features of hemorrhagic complications secondary to optic nerve head drusen (ONHD) using spectral domain optical coherence tomography (SD-OCT).

METHODS

Sixty-three consecutive patients with SD-OCT-documented ONHD who presented at Seoul National University Bundang Hospital from December 2009 to July 2012 were included. Full ophthalmologic examinations, including fundus photographs, SD-OCT, fundus angiography, and visual field tests were analyzed in a total of 101 ONHD-positive eyes from 63 patients.

RESULTS

Hemorrhagic ONHD complications were found in 7 eyes (7%) from a total of 101 eyes with ONHD. All of them had buried ONHD (visualized with SD-OCT) and myopia (mean spherical equivalent = -4.00 ± 2.35 diopters). Patients with ONHD hemorrhagic complications had smaller disk diameters than patients without hemorrhagic complications (1,308 ± 166 vs. 1,555 ± 217 μm, P = 0.004). Peripapillary hemorrhages were classified into the following 3 types based on SD-OCT findings: subretinal (6 eyes, 86%), retinal (5 eyes, 71%), and vitreous hemorrhage (4 eyes, 57%). Six patients (86%) complained of the recent onset of visual symptoms, but visual acuities at presentation were 20/20 in all patients. In the three patients who were followed up, most hemorrhages were absorbed without complications.

CONCLUSION

Peripapillary hemorrhage can often occur in patients with buried ONHD and small disk diameters. As SD-OCT can be used to visualize ONHD beneath hemorrhage, it is helpful with the differential diagnosis and follow-up evaluation.

Multimodal imaging of optic disc drusen

PURPOSE

To evaluate optic disc drusen, extracellular protein deposits known to contain numerous aggregates of mitochondria, using multimodal modalities featuring optical coherence tomography (OCT) and autofluorescence imaging.

DESIGN

Retrospective observational case series.

METHODS

Eyes with optic nerve drusen were examined with enhanced depth imaging (EDI)-OCT, swept source OCT, and fundus autofluorescence using a fundus camera.

RESULTS

Twenty-six eyes of 15 patients with optic disc drusen were evaluated. EDI-OCT and swept source OCT showed multiple optic disc drusen at different levels; most were located immediately anterior to the lamina cribrosa. The drusen were ovoid regions of lower reflectivity that were bordered by hyperreflective material, and in 12 eyes (46.2%) there were internal hyperreflective foci. The mean diameter of the optic disc drusen as measured in OCT images was 686.8 (standard deviation ± 395.2) μm. There was a significant negative correlation between the diameter of the optic disc drusen and the global retinal nerve fiber layer thickness (r = -0.61, P = .001). There was a significant negative correlation between proportion of the optic disc drusen area occupied by optic nerve drusen as detected by autofluorescence imaging and the global retinal nerve fiber layer thickness (r = -0.63, P = .001).

CONCLUSIONS

Deeper-penetration OCT imaging demonstrated the internal characteristics of optic disc drusen and their relationship with the lamina cribrosa in vivo. This study also showed that both the larger the drusen and the more area of the optic canal occupied by drusen, the greater the associated retinal nerve fiber layer abnormalities.

Super-resolution spectral estimation of optical micro-angiography for quantifying blood flow within microcirculatory tissue beds in vivo

In this paper, we propose a super-resolution spectral estimation technique to quantify microvascular hemodynamics using optical microangiography (OMAG) based on optical coherence tomography (OCT). The proposed OMAG technique uses both amplitude and phase information of the OCT signals which makes it sensitive to the axial and transverse flows. The scanning protocol for the proposed method is identical to three-dimensional ultrahigh sensitive OMAG, and is applicable for in vivo measurements. In contrast to the existing capillary flow quantification methods, the proposed method is less sensitive to tissue motion and does not have aliasing problems due fast flow within large blood vessels. This method is analogous to power Doppler in ultrasonography and estimates the number of red blood cells passing through the beam as opposed to the velocity of the particles. The technique is tested both qualitatively and quantitatively by using OMAG to image microcirculation within mouse ear flap in vivo.

Morphologic characteristics of optic nerve head drusen on spectral-domain optical coherence tomography

PURPOSE

To evaluate the morphologic characteristics of optic nerve head drusen.

DESIGN

Retrospective case series.

METHODS

setting: Institutional (Seoul National University Bundang Hospital). patients: Sixty-one patients with optic nerve head drusen. observation procedure: Visible and buried optic nerve head drusen were identified using funduscopy, whereas homogenous and nonhomogenous optic nerve head drusen were identified using spectral-domain optical coherence tomography images. Buried optic nerve head drusen were classified according to the size. main outcome measures: Classification of optic nerve head drusen.

RESULTS

Of 99 eyes in 61 patients, optic nerve head drusen were buried in 95 eyes and visible in 4 eyes. The patients with visible optic nerve head drusen were older on average than those with buried optic nerve head drusen (53.3 ± 8.6 years vs 13.5 ± 7.1 years; P < .001) and exhibited larger disc diameters (1643 ± 265 μm vs 1287 ± 185 μm; P = .016). All 4 eyes with visible optic nerve head drusen exhibited hyperreflective borders, which were not found in patients with buried optic nerve head drusen. Of 95 eyes with buried optic nerve head drusen, 64 eyes (67%) showed homogenous internal reflectivity, whereas 31 eyes (33%) showed nonhomogenous reflectivity with lobulations. Large optic nerve head drusen were associated with a small optic disc diameter, nonhomogenous internal reflectivity, a partial highly reflective border, intraretinal cysts, and increased temporal retinal nerve fiber layer thickness.

CONCLUSIONS

Optic nerve head drusen have a diverse spectrum of spectral-domain optical coherence tomography findings associated with patient age and disc size.

Fluorescein angiographic identification of optic disc drusen with and without optic disc edema

BACKGROUND

The fluorescein angiographic criteria for differentiating optic disc drusen (ODD) from optic disc edema have been unclear. We designed a study to identify distinguishing angiographic features of each and to apply them to cases where both drusen and edema were present.

METHODS

A computer search was performed for cases evaluated in a university academic neuro-ophthalmology consultative practice and coded as ODD; all cases were reviewed, and those with fluorescein angiography were selected for further study. Cases were classified as either buried or surface ODD. Ten cases with papilledema were selected for comparison. Eight cases of coexistent drusen and edema were identified. Autofluorescence, early leakage, early blockage, early and late nodular staining, late peripapillary staining, and late leakage were tabulated.

RESULTS

Two hundred sixteen cases of ODD were identified; 62 (116 eyes) had adequate fluorescein angiography for study. Twenty-three eyes were classified as surface ODD; 90% demonstrated early nodular staining of the disc, with late nodular staining in 90% and late circumferential peripapillary staining in 22%; autofluorescence was visible in 93% with preinjection photography. Eighty-three eyes were classified as buried ODD; 25% demonstrated early nodular staining, with late nodular staining in 29% and late circumferential peripapillary staining in 80%; autofluorescence was visible in 12% of those with preinjection photography. In 9 eyes, buried ODD were present with superimposed true edema. In these eyes, early dye leakage, late nodular hyperfluorescence, and late leakage were present.

CONCLUSION

Early and late fluorescein angiographic features reliably distinguish ODD from edema and may be particularly useful when the conditions coexist.

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.

Use of optical coherence tomography to evaluate papilledema and pseudopapilledema

Idiopathic intracranial hypertension (IIH), or pseudotumor cerebri, describes a condition of elevated intracranial pressure (ICP) that typically presents in obese women of childbearing age with symptoms and signs of posture-dependent headaches, pulsatile tinnitus, visual changes, and papilledema. Optical coherence tomography (OCT) has begun to be utilized as an adjunctive, quantitative tool in the evaluation of patients with IIH to help distinguish between true optic nerve head edema and pseudopapilledema, and to contribute to our understanding of the consequences of prolonged optic nerve edema. Although few longitudinal studies of patients with IIH have been published to date, it appears that there may be a correlation between retinal nerve fiber layer (RNFL) thickness and visual function. With the new spectral domain OCT, additional parameters of the optic nerve imaging, including volume and height measurements, might provide greater sensitivity of the response to treatment and the long-term visual outcome in patients with IIH.

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.

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.

Spectral domain optical coherence tomography in glaucoma: qualitative and quantitative analysis of the optic nerve head and retinal nerve fiber layer (an AOS thesis)

PURPOSE

To demonstrate that video-rate spectral domain optical coherence tomography (SDOCT) can qualitatively and quantitatively evaluate optic nerve head (ONH) and retinal nerve fiber layer (RNFL) glaucomatous structural changes. To correlate quantitative SDOCT parameters with disc photography and visual fields.

METHODS

SDOCT images from 4 glaucoma eyes (4 patients) with varying stages of open-angle glaucoma (ie, early, moderate, late) were qualitatively contrasted with 2 age-matched normal eyes (2 patients). Of 61 other consecutive patients recruited in an institutional setting, 53 eyes (33 patients) met inclusion/exclusion criteria for quantitative studies. Images were obtained using two experimental SDOCT systems, one utilizing a superluminescent diode and the other a titanium:sapphire laser source, with axial resolutions of about 6 microm and 3 microm, respectively.

RESULTS

Classic glaucomatous ONH and RNFL structural changes were seen in SDOCT images. An SDOCT reference plane 139 microm above the retinal pigment epithelium yielded cup-disc ratios that best correlated with masked physician disc photography cup-disc ratio assessments. The minimum distance band, a novel SDOCT neuroretinal rim parameter, showed good correlation with physician cup-disc ratio assessments, visual field mean deviation, and pattern standard deviation (P values range, .0003-.024). RNFL and retinal thickness maps correlated well with disc photography and visual field testing.

CONCLUSIONS

To our knowledge, this thesis presents the first comprehensive qualitative and quantitative evaluation of SDOCT images of the ONH and RNFL in glaucoma. This pilot study provides basis for developing more automated quantitative SDOCT-specific glaucoma algorithms needed for future prospective multicenter national trials.