Comparative Intraoperative Anterior Segment OCT Findings in Pediatric Patients with and without Glaucoma

Anterior segment optical coherence tomography (AS-OCT) in strabismus following trauma

We describe 3 cases of ocular trauma that presented with strabismus. Anterior segment optical coherence tomography was used to delineate the morphology of extraocular muscle insertions and proved helpful in diagnosis and management.

Primary congenital glaucoma: An iridotrabeculodysgenesis?

PURPOSE

To analyze primary congenital glaucoma (PCG) anterior chamber and angle anomalies over 360° as possible biomarkers of severity and prognosis.

METHODS

A cross-sectional observational study was conducted analyzing anterior segment anomalies of PCG patients over 4 years of age who underwent trabeculectomy combined with trabeculotomy and age-matched controls using anterior segment optical coherence tomography (ASOCT), CASIA-2. Anterior iridotrabecular adhesions or anterior iris insertion was identified and quantified from the scleral spur using the iridotrabecular contact (ITC) index parameter as a surrogate.

RESULTS

There was a variable but significantly increased anterior iridotrabecular adhesion on ITC index, ITC area, corneal volume, anterior chamber volume, iris volume, anterior chamber depth, and small/absent trabecular meshwork in PCG eyes compared to control eyes. In PCG eyes, anterior iridotrabecular adhesion had a positive correlation with pre-operative central corneal thickness (CCT) (r = 0.53, P = 0.02), review iris thickness (r = 0.4, P = 0.04), and ITC area (r = 0.85, P < 0.001). Review iris thickness had a negative correlation with pre-operative vertical cup-disc ratio (r = -0.51, P = 0.008). Iris hypoplasia with fewer or absent folds, collarette, pupillary ruff, and pupillary ruff to collarette distance was significantly different from controls.

CONCLUSION

ASOCT in PCG eyes has shown that they have variable anterior iridotrabecular tissue adhesions, anomalous tissue/membranes in the angle, and iris hypoplasia correlating with pre-operative cup-disc ratio. These features could be used as gonioscopic and clinical biomarkers to assess the severity and prognosis of the disease. The presence of abnormal iris morphology and iridotrabecular tissue anomalies in PCG suggests that it is more than just isolated trabeculodysgenesis and is probably best considered as part of the anterior segment dysgenesis spectrum.

Intraoperative Optical Coherence Tomography for Ab Interno Trabecular Bypass Glaucoma Surgery

ABSTRACT

The purpose of this study was to demonstrate a case of a novel surgical technique utilizing intraoperative optical coherence tomography (iOCT) to aid implantation and optimal placement of 2 trabecular bypass minimally invasive glaucoma surgery devices-the iStent inject W and the Hydrus microstent. In iStent inject W implantation, where the depth of stent implantation has been correlated to postoperative outcomes. the iOCT allowed real-time appreciation of device implantation depth relative to the trabecular meshwork surface. In Hydrus microstent implantation, the iOCT allowed confirmation of successful stent placement within the Schlemm canal, and may help in cases where intraoperative gonioscopic view of the 3 microstent windows is impeded. This case demonstrated the use of the iOCT as an imaging adjunct to ensure optimal placement of trabecular bypass minimally invasive glaucoma surgery devices such as the iStent inject W and Hydrus microstent.

Anterior segment parameters on optical coherence tomography in healthy South Asian children

PURPOSE

High resolution spectral domain optical coherence tomography (SD-OCT) was used to assess the anterior segment structure parameters in healthy South Asian children.

METHODS

108 eyes of 54 healthy children ≤ 16 years were recruited after a thorough eye exam. The anterior segment analysis was be done by Optopol Revo 80 high resolution SD-OCT. Central corneal thickness (CCT), Angle opening distance (AOD), Anterior chamber (AC) angle, Trabecular iris space area (TISA), Trabecular iris angle (TIA), iris thickness at 2 mm, internal AC diameter and lens vault were evaluated.

RESULTS

Mean age was 11.38 years. Mean IOP was 13.63 mmHg, mean axial length, 22.82 mm, mean spherical equivalent, -0.14 D, mean CCT, 532.6 µm and mean CDR was 0.31. The mean internal AC diameter was 11609.15 µm. The nasal and temporal AC angles was 53.54° and 50.37°, respectively [P = .033]. The nasal and temporal AOD500 were 0.9 mm and 0.85 mm, respectively [P = .629]. The nasal and temporal AOD750 were 1.21 mm and 1.06 mm, respectively [P = .583]. The nasal TIA was 41.75°; the temporal TIA; 40.24° [P = .325]. The nasal TISA500 was 0.33 mm²; the temporal TISA500, 0.31 mm² [P = .012]. The nasal TISA750 was 0. 59 mm²; the temporal TISA750, 0.56 mm² [P = .746]. The nasal iris thickness at 2 mm was 483.54 µm; the temporal iris thickness, 505.8 µm [P = .273]. The mean lens vault was -519.58 µm.

CONCLUSIONS

Our study data depicts the normal anterior segment parameters in healthy Pakistani children.

Clinical applications for intraoperative optical coherence tomography: a systematic review

In this systematic review, we provide an overview of the current state of intraoperative optical coherence tomography (iOCT). As iOCT technology is increasingly utilized, its current clinical applications and potential uses warrant attention. Here, we categorize the findings of various studies by their respective fields, including the use of iOCT in vitreoretinal surgery, corneal surgery, glaucoma surgery, cataract surgery, and pediatric ophthalmology. The trend observed in recent decades towards performing minimally invasive ophthalmic surgery has caused practitioners to recognize the limitations of using a conventional surgical microscope for intraoperative visualization. Thus, the superior visualization provided by iOCT can improve the safety of these surgical techniques and promote the development of new minimally invasive ophthalmic surgeries. Landmark prospective studies found that iOCT can significantly affect surgical decision making and can cause a subsequent change in surgical strategy, and the use of iOCT has potential to improve surgical outcome. Despite these advantages, however, iOCT is still a relatively new technique, and beginning users of iOCT can encounter limitations that can preclude their reaching the full potential of iOCT and in this respect several improvements are needed.

Development and validation of methods to visualize conventional aqueous outflow pathways in canine primary angle closure glaucoma

PURPOSE

Angle closure glaucoma (PACG) is highly prevalent in dogs and is often refractory to medical therapy. We hypothesized that pathology affecting the post-trabecular conventional aqueous outflow pathway contributes to persistent intraocular pressure (IOP) elevation in dogs with PACG. The goal of this study was to determine the potential for aqueous angiography (AA) and optical coherence tomography (OCT) to identify abnormalities in post-trabecular aqueous outflow pathways in canine PACG.

METHODS

AA and anterior segment OCT (Spectralis HRA + OCT) were performed ex vivo in 19 enucleated canine eyes (10 normal eyes and 9 irreversibly blind eyes from canine patients enucleated for management of refractory PACG). Eyes were cannulated and maintained at physiologic IOP (10-20 mmHg) prior to intracameral infusion of fluorescent tracer. OCT scleral line scans were acquired in regions of high and low perilimbal AA signal. Eyes were then perfusion fixed and cryosections prepared from 10/10 normal and 7/9 PACG eyes and immunolabeled for a vascular endothelial marker.

RESULTS

Normal canine eyes showed segmental, circumferential limbal AA signal, whereas PACG eyes showed minimal or no AA signal. AA signal correlated with scleral lumens on OCT in normal dogs, but lumens were generally absent or flattened in PACG eyes. Collapsed vascular profiles were identified in tissue sections from PACG eyes, including those in which no lumens were identified on AA and OCT.

CONCLUSIONS

In canine eyes with PACG, distal aqueous outflow channels are not identifiable by AA, despite normalization of their IOP, and intra-scleral vascular profiles are collapsed on OCT and histopathology.

OCT on Anterior Segment Anomalies of the Eye in a Polish Paediatric Cohort: Diagnostic and Therapeutic Challenges

Purpose

To present applications of anterior segment optical coherent tomography (AS OCT) for anomalies of the eye in a Polish paediatric cohort.

Materials and Methods

Seventy-four eyes of infants and older children were examined. The majority of them underwent general anaesthesia to allow OCT to be performed in the operating room, but a few were examined in a routine way. We focused on corneal, anterior chamber, iris, and lens disorders. Measurements included corneal morphology, anatomy of the anterior chamber, and general involvement of surrounding tissues in pathologic lesions.

Results

We divided the paediatric patients into several groups by considering the type of disease and involvement of particular tissues. The groups were selected based on OCT usefulness in describing their ocular disorders.

Conclusion

The collected anterior segment disorders showed huge usefulness for paediatric diagnosis and treatment planning.