Handheld optical coherence tomography removes barriers to imaging the eyes of young children

Applications of optical coherence tomography angiography in glaucoma: current status and future directions

Glaucoma is a leading cause of irreversible blindness worldwide, with its pathophysiology remaining inadequately understood. Among the various proposed theories, the vascular theory, suggesting a crucial role of retinal vasculature deterioration in glaucoma onset and progression, has gained significant attention. Traditional imaging techniques, such as fundus fluorescein angiography, are limited by their invasive nature, time consumption, and qualitative output, which restrict their efficacy in detailed retinal vessel examination. Optical coherence tomography angiography (OCTA) emerges as a revolutionary imaging modality, offering non-invasive, detailed visualization of the retinal and optic nerve head microvasculature, thereby marking a significant advancement in glaucoma diagnostics and management. Since its introduction, OCTA has been extensively utilized for retinal vasculature imaging, underscoring its potential to enhance our understanding of glaucoma's pathophysiology, improving diagnosis, and monitoring disease progression. This review aims to summarize the current knowledge regarding the role of OCTA in glaucoma, particularly its potential applications in diagnosing, monitoring, and understanding the pathophysiology of the disease. Parameters pertinent to glaucoma will be elucidated to illustrate the utility of OCTA as a tool to guide glaucoma management.

Intracranial Pressure Patterns in Children with Sagittal Craniosynostosis

BACKGROUND

Elevated intracranial pressure (ICP) in sagittal craniosynostosis has a wide spectrum of reported incidence, and patterns are not well understood across infancy and childhood. Characterizing the natural history of ICP in this population may clarify risks for neurocognitive delay and inform treatment decisions.

METHODS

Infants and children with sagittal craniosynostosis and unaffected control subjects were prospectively evaluated with spectral-domain optical coherence tomography from 2014 to 2021. Elevated ICP was determined based on previously validated algorithms using retinal optical coherence tomography parameters.

RESULTS

Seventy-two patients with isolated sagittal craniosynostosis and 25 control subjects were evaluated. Overall, 31.9% ( n = 23) of patients with sagittal craniosynostosis had evidence of ICP greater than or equal to 15 mmHg, and 27.8% ( n = 20) of patients had ICP greater than or equal to 20 mmHg. Children with sagittal craniosynostosis younger than 6 months were more likely to have normal ICP (88.6% <15 mmHg; 91.4% <20 mmHg) than those aged between 6 and 12 months (54.5%, P = 0.013; 54.5%, P = 0.005) than those older than 12 months (46.2%, P < 0.001; 53.8%, P = 0.001). ICP was directly correlated with severity of scaphocephaly ( P = 0.009). No unaffected control subjects at any age exhibited retinal thickening suggestive of elevated ICP.

CONCLUSION

Elevated ICP is rare in isolated sagittal craniosynostosis younger than 6 months, but it becomes significantly more common after 6 months of age, and may correlate with severity of scaphocephaly.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, II.

Posterior Segment Optical Coherence Tomography in Uncooperative Paediatric Patients Using Exo-Illumination and Microscope-Integrated Optical Coherence Tomography

BACKGROUND AND OBJECTIVE

To describe a non-invasive technique for the acquisition of retinal optical coherence tomography (OCT) scans in paediatric patients undergoing examination under general anaesthesia (EUA) using microscope-integrated OCT (MIOCT).

STUDY DESIGN

Prospective observational study Methods and Material: The study included 10 paediatric patients undergoing EUA for posterior segment pathology. These patients underwent OCT using MIOCT. No sclerotomy was made during imaging. The fundus was externally illuminated with a 25 gauge endoilluminator probe placed at the limbus and directed towards the posterior pole to aid in image acquisition by MIOCT (exo-illumination). Imaging for all patients was done by two trained vitreoretinal surgeons independently. Acquisition time was recorded for each surgeon. Interobserver variability in acquisition time and image quality was assessed to estimate the reliability of the novel imaging technique.

RESULTS

In nine cases (90%), MIOCT successfully imaged the posterior segment pathology while in one case (10%) of X-linked retinoschisis, it failed to detect an inner retinal break located anteriorly at the equator. The mean acquisition time for surgeons one and two was 211.75 ± 26.00 and 212.58 ± 23.47 seconds, respectively. There was no significant difference in total image acquisition time between the two surgeons (P = 1.0) and the findings of both surgeons were comparable for structural morphology. 4x4 mm-sized scans provided the best delineation in macular pathology, while a 16x16 mm scan size was best suited for localising the area of interest and post-equatorial pathology.

CONCLUSION

Using this technique acquisition of posterior segment OCT scans can be achieved non-invasively, using exo-illumination and MIOCT in paediatric patients undergoing EUA.

Advances in Optical Coherence Tomography Imaging Technology and Techniques for Choroidal and Retinal Disorders

Optical coherence tomography (OCT) imaging has played a pivotal role in the field of retina. This light-based, non-invasive imaging modality provides high-quality, cross-sectional analysis of the retina and has revolutionized the diagnosis and management of retinal and choroidal diseases. Since its introduction in the early 1990s, OCT technology has continued to advance to provide quicker acquisition times and higher resolution. In this manuscript, we discuss some of the most recent advances in OCT technology and techniques for choroidal and retinal diseases. The emerging innovations discussed include wide-field OCT, adaptive optics OCT, polarization sensitive OCT, full-field OCT, hand-held OCT, intraoperative OCT, at-home OCT, and more. The applications of these rising OCT systems and techniques will allow for a closer monitoring of chorioretinal diseases and treatment response, more robust analysis in basic science research, and further insights into surgical management. In addition, these innovations to optimize visualization of the choroid and retina offer a promising future for advancing our understanding of the pathophysiology of chorioretinal diseases.

Remote Imaging Capture with Widefield Swept-Source OCT Angiography During the COVID-19 Pandemic

Purpose

The COVID-19 pandemic has had a widespread impact on the health sector worldwide, both in the clinical and research subsector. This has necessitated for the invention of protocols compliant with social distancing policies to efficiently tackle the current needs. Our aim is to describe a novel remote imaging technique, which helped us continue our research with widefield swept-source optical coherence tomography angiography (WF SS-OCTA).

Patients and Methods

As a part of this cross-sectional observational study from August 2020 to September 2020 at Massachusetts Eye and Ear (MEE), we used our institute approved remote desktop, outside of MEE, to gain full access to the on-site WF SS-OCTA device in the imaging room for the purpose of remote imaging. With only the patient being in the imaging room, effective communication was established via video conferencing on an encrypted tablet computer device for the entire procedure.

Results

We imaged four patients with various retinal pathologies, aged 32–69 years. All images obtained were of high quality and signal strength (median score 9/10 for both) and all patients reported a highly satisfactory, comfortable, and safe experience amidst the COVID-19 pandemic.

Conclusion

This novel method is better for remote imaging compared to the previously described techniques as it is time and cost effective, requires limited resources without compromising the image quality or patient satisfaction and adheres to the various guidelines for infection control, most importantly social distancing. As a paradigm shift, this can also be employed in future for setups with limited staff like busy emergency departments or a rural setup with limited access or difficult commute, in the “new-normal” era.