Variability Within Optic Nerve Optical Coherence Tomography Measurements Distinguishes Papilledema From Pseudopapilledema

Diagnostic utility of point-of-care ultrasound and optical coherence tomography for papilloedema in children: a prospective pilot study

BACKGROUND/AIMS

Papilloedema is an important sign of serious neurological disease, but it can be difficult to detect on funduscopy. The purpose of this study was to determine the diagnostic accuracy of point-of-care ultrasound (POCUS) and optical coherence tomography (OCT) for detecting papilloedema in children.

METHODS

This was a prospective observational study at a tertiary care paediatric hospital. Patients were eligible for the study if they underwent a lumbar puncture with opening pressure and had high-quality POCUS and OCT imaging.

RESULTS

A total of 63 eyes from 32 patients were included in the study, 41 (65%) with papilloedema and 22 (35%) without. There were statistically significant differences between the groups in the optic disc elevation (ODE) (p<0.001) and optic nerve sheath diameter (ONSD) (p<0.001) on POCUS, and in the average retinal nerve fibre layer (rNFL) thickness on OCT (p<0.001). Average rNFL thickness had the highest diagnostic accuracy with an area under the curve (AUC) of 0.999 and a 100% sensitivity and 95% specificity for papilloedema (threshold value of ≥108 µm). ODE had an AUC of 0.866 and a 93% sensitivity and 55% specificity (threshold value of ≥0.5 mm). ONSD had an AUC of 0.786 and a 93% sensitivity and 45% specificity (threshold value of ≥5.5 mm).

CONCLUSION

Both OCT and POCUS are potentially useful tools to help diagnose papilloedema in children. Larger studies are needed to further define the role and accuracy of POCUS and OCT in assessing papilloedema in children.

Exploring the utility of retinal optical coherence tomography as a biomarker for idiopathic intracranial hypertension: a systematic review

This study aimed to examine the existing literature that investigated the effectiveness of optical coherence tomography (OCT) and optical coherence tomography angiography (OCT-A) as a biomarker for idiopathic intracranial hypertension (IIH). Our search was conducted on January 17th, 2024, and included the databases, Medline, Scopus, Embase, Cochrane, Latin American and Caribbean Health Sciences Literature (LILACS), International Standard Randomized Controlled Trial Number (ISRCTN) registry, and the International Clinical Trials Registry Platform (ICTRP). Our final review included 84 articles. In 74 studies, OCT was utilized as the primary ocular imaging method, while OCT-A was employed in two studies including eight studies that utilized both modalities. Overall, the results indicated that IIH patients exhibited significant increases in retinal nerve fiber layer (RNFL) thickness, total retinal and macular thickness, optic nerve head volume, and height, optic disc diameter and area, rim area, and thickness compared to controls. A significant correlation was observed between cerebrospinal fluid (CSF) pressure and OCT parameters including RNFL thickness, total retinal thickness, macular thickness, optic nerve head volume, and optic nerve head height. Interventions aimed at lowering CSF pressure were associated with a substantial improvement in these parameters. Nevertheless, studies comparing peripapillary vessel density using OCT-A between IIH patients and controls yielded conflicting results. Our systematic review supports OCT as a powerful tool to accurately monitor retinal axonal and optic nerve head changes in patients with IIH. Future research is required to determine the utility of OCT-A in IIH.

Diagnostic dilemma of papilledema and pseudopapilledema

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

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

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

Discriminating Between Papilledema and Optic Disc Drusen Using 3D Structural Analysis of the Optic Nerve Head

BACKGROUND AND OBJECTIVES

The distinction of papilledema from other optic nerve head (ONH) lesions mimicking papilledema, such as optic disc drusen (ODD), can be difficult in clinical practice. We aimed the following: (1) to develop a deep learning algorithm to automatically identify major structures of the ONH in 3-dimensional (3D) optical coherence tomography (OCT) scans and (2) to exploit such information to robustly differentiate among ODD, papilledema, and healthy ONHs.

METHODS

This was a cross-sectional comparative study of patients from 3 sites (Singapore, Denmark, and Australia) with confirmed ODD, those with papilledema due to raised intracranial pressure, and healthy controls. Raster scans of the ONH were acquired using OCT imaging and then processed to improve deep-tissue visibility. First, a deep learning algorithm was developed to identify major ONH tissues and ODD regions. The performance of our algorithm was assessed using the Dice coefficient. Second, a classification algorithm (random forest) was designed to perform 3-class classifications (1: ODD, 2: papilledema, and 3: healthy ONHs) strictly from their drusen and prelamina swelling scores (calculated from the segmentations). To assess performance, we reported the area under the receiver operating characteristic curve for each class.

RESULTS

A total of 241 patients (256 imaged ONHs, including 105 ODD, 51 papilledema, and 100 healthy ONHs) were retrospectively included in this study. Using OCT images of the ONH, our segmentation algorithm was able to isolate neural and connective tissues and ODD regions/conglomerates whenever present. This was confirmed by an averaged Dice coefficient of 0.93 ± 0.03 on the test set, corresponding to good segmentation performance. Classification was achieved with high AUCs, that is, 0.99 ± 0.001 for the detection of ODD, 0.99 ± 0.005 for the detection of papilledema, and 0.98 ± 0.01 for the detection of healthy ONHs.

DISCUSSION

Our artificial intelligence approach can discriminate ODD from papilledema, strictly using a single OCT scan of the ONH. Our classification performance was very good in the studied population, with the caveat that validation in a much larger population is warranted. Our approach may have the potential to establish OCT imaging as one of the mainstays of diagnostic imaging for ONH disorders in neuro-ophthalmology, in addition to fundus photography.

Upper Limit of Retinal Nerve Fibre Layer Thickness in Patients with Pseudopapilloedema

An initial misdiagnosis of papilloedema in a patient with optic nerve head swelling can be anxiety-provoking and may result in unnecessary, invasive, and costly tests. Cirrus high definition, spectral domain-optical coherence tomography (Cirrus HD-OCT) may provide a rapid and non-invasive test. We sought to determine an upper limit of average retinal nerve fibre layer (RNFL) thickness in patients with pseudopapilloedema without visible drusen using Cirrus HD-OCT that could be utilised in conjunction with the clinical presentation and physical examination when managing patients with optic nerve head swelling. Inclusion criteria consisted of at least two neuro-ophthalmological visits and repeated imaging of the optic nerve head with Cirrus HD-OCT at least 6 months apart. Exclusion criteria included clinically visible drusen along with previous or concomitant diagnosis of retinal or other optic nerve pathology. Thirty-eight eyes from 19 patients with pseudopapilloedema were included in this study. The upper limit of average RNFL thickness was defined as two standard deviations above the mean of the average RNFL thickness and was calculated to be 158.65 µm for scans obtained with Cirrus HD-OCT devices. A patient with suspected optic nerve head swelling, an average RNFL thickness less than 158.65 µm, and no other evidence of papilloedema or neurological signs or symptoms can be managed with serial follow-ups with OCT imaging for at least 6 months. If the patient continues to have no clinical symptoms suggesting increased intracranial pressure and the average RNFL thickness is stable, the likelihood of papilloedema is minimal.

Idiopathic Intracranial Hypertension: Incidental Discovery Versus Symptomatic Presentation

BACKGROUND

We aim to compare the clinical characteristics, disease course and visual outcomes between Canadian patients with idiopathic intracranial hypertension (IIH) who were incidentally discovered and those who sought care due to symptoms of IIH.

METHODS

Retrospective chart review of consecutive IIH patients conducted at tertiary neuro-ophthalmology clinics. Patients were divided into Group 1 (incidentally discovered disease) and Group 2 (patients seeking medical care due to symptoms of intracranial hypertension).

RESULTS

One hundred eighty-six patients were included in the study; of which, 75 (40.3%; Group-1) were incidentally discovered and 111 presented due to symptoms of IIH (Group-2). There were no differences in proportion of females (P = 0.101), age (P = 0.450), body mass index (P = 0.386), MRI findings of empty or partially empty sella (P = 0.41), and sella grade (P = 0.704). Group-1 patients were less likely to have experienced headache (P = 0.001), transient visual obscurations (P < 0.001), and diplopia (P = 0.026) at presentation. Group-1 patients were less likely to receive medical (P < 0.001) and surgical (P = 0.004) treatment. There was no difference in proportion of patients who lost weight between the groups (P = 0.848). At baseline, Group-1 patients exhibited better visual acuity (P = 0.001), Humphrey mean deviation (P < 0.001) and retinal nerve fiber layer thickness (P < 0.001). Group-1 patients continued to have better visual acuity (P = 0.002) and Humphrey mean deviation (P < 0.001) at final follow-up.

CONCLUSIONS

A significant portion of IIH patients were incidentally discovered. This group exhibited a favorable prognosis and only a minority of these patients required treatment. The way in which patients enter the medical system may be a valuable way to risk stratify IIH patients.