Investigation of Macular Choroidal Thickness and Blood Flow Change by Optical Coherence Tomography Angiography After Posterior Scleral Reinforcement

Clinical outcomes of posterior scleral reinforcement in Chinese high myopia children

We aim to observe the posterior scleral reinforcement (PSR) clinical outcomes of children with high myopia and analyze the retinal vessel alteration before and after PSR by using angiography optical coherence tomography (angio-OCT). Fifty-six pediatric participants (112 eyes) clinically diagnosed high myopia were recruited and were treated by PSR in Shanghai Children's Hospital from June 1, 2021 to May 1, 2023. The average age ranged from 5.42 to 14.83 years (mean 8.83 years) and mean follow up duration was 8.7 months (3-24 months). The axial length (AL) was significantly shortened after PSR (p < 0.05). The spherical equivalent (SE) and the best-corrected visual acuity (BCVA) were also improved without severe rejection in the follow-up. Compared with baseline, angio-OCT parafoveal vessel indices including vascular area density (VAD) and vascular skeleton density (VSD) on the superficial capillary plexus layer (SCPL), as well as VAD and vessel perimeter index (VPI) on the deep capillary plexus layer (DCPL), were significantly increased after PSR surgery (p < 0.05). VPI on the SCPL, vascular diameter index (VDI) and VSD on the DCPL were also improved without statistical difference after PSR. The VSD on SCPL, VAD on DCPL of the right eyes and the VPI on SCPL of the left eyes were significantly increased after PSR (p < 0.05). PSR surgery can shorten the AL and can stable BCVA and SE in high myopia children. The angio-OCT parameters indicated that the retinal microcirculation supply was significantly improved after PSR.

Response of the human choroid to short-term changes in eyelid and periocular temperature

CLINICAL RELEVANCE

Choroidal thickness measurement is gaining popularity in clinical practice and research as an early indicator of myopia progression. Understanding the influence of temperature on choroidal thickness changes will improve the reliability of the measures.

BACKGROUND

It has been suggested that environmental temperature may affect choroidal thickness and blood flow, with potential implications for ocular disease and refractive development. This study investigates the effect of changes in eyelid/ocular adnexa temperature on choroidal thickness.

METHODS

In a paired-eye study, 20 young, healthy subjects received a warm stimulus (heat pack) over one closed eye and simultaneously a cold stimulus (ice pack) over the other for 10 min. Eyelid temperatures were monitored with thermal probes, and optical coherence tomography scans of the retina and choroid were taken before and after heating and cooling, and then every 5 min during a 15-min recovery period. Retinal and choroidal thicknesses were measured across the macular region (6 mm), including the subfoveal (1 mm), parafoveal (1-3 mm), and perifoveal (3-5 mm) regions, and compared between the cooled and warmed eyes.

RESULTS

When the thermal stimuli were applied, eyelid surface temperatures changed predictably and remained significantly different (by approximately 10-15°C) between the eyes after 2 min (p < .001). Relative to the warmed eye, macular choroidal thickness in the cooled eye increased significantly after 10 min of treatment (p = .004). This choroidal thickening response occurred in the subfoveal, parafoveal, and perifoveal regions (all p < .05). Upon removal of the thermal stimuli, choroidal thickness rapidly returned to the baseline and was no longer different between the cooled and warmed eye (p = .641).

CONCLUSION

Cooling the anterior eye by application of a cold stimulus directly onto the closed eyelid caused a small but significant increase in choroidal thickness relative to warming the anterior eye, demonstrating that the choroid can modulate its thickness rapidly and transiently in response to local temperature changes.

Forecasting Myopic Maculopathy Risk Over a Decade: Development and Validation of an Interpretable Machine Learning Algorithm

Purpose

The purpose of this study was to develop and validate prediction model for myopic macular degeneration (MMD) progression in patients with high myopia.

Methods

The Zhongshan High Myopia Cohort for model development included 660 patients aged 7 to 70 years with a bilateral sphere of ≤-6.00 diopters (D). Two hundred twelve participants with an axial length (AL) ≥25.5 mm from the Chinese Ocular Imaging Project were used for external validation. Thirty-four clinical variables, including demographics, lifestyle, myopia history, and swept source optical coherence tomography data, were analyzed. Sequential forward selection was used for predictor selection, and binary classification models were created using five machine learning algorithms to forecast the risk of MMD progression over 10 years.

Results

Over a median follow-up of 10.9 years, 133 patients (20.2%) showed MMD progression in the development cohort. Among them, 69 (51.9%) developed newly-onset MMD, 11 (8.3%) developed patchy atrophy from diffuse atrophy, 54 (40.6%) showed an enlargement of lesions, and 9 (6.8%) developed plus signs. Top six predictors for MMD progression included thinner subfoveal choroidal thickness, longer AL, worse best-corrected visual acuity, older age, female gender, and shallower anterior chamber depth. The eXtreme Gradient Boosting algorithm yielded the best discriminative performance (area under the receiver operating characteristic curve [AUROC] = 0.87 ± 0.02) with good calibration in the training cohort. In a less myopic external validation group (median -5.38 D), 48 patients (22.6%) developed MMD progression over 4 years, with the model's AUROC validated at 0.80 ± 0.008.

Conclusions

Machine learning model effectively predicts MMD progression a decade ahead using clinical and imaging indicators. This tool shows promise for identifying "at-risk" high myopes for timely intervention and vision protection.

Long-term outcomes of anti-vascular endothelial growth factor therapy with and without posterior scleral reinforcement on myopic maculopathy in myopic choroidal neovascularization eyes

BACKGROUND

Anti-vascular endothelial growth factor (anti-VEGF) therapy is used for myopic choroidal neovascularization (mCNV). Patchy chorioretinal atrophy (pCRA) enlargement has been reported in mCNV cases associated with vision loss. Our aim was to compare the long-term effectiveness of anti-VEGF therapy alone versus anti-VEGF followed by posterior scleral reinforcement (PSR) in controlling myopic maculopathy in mCNV eyes.

METHODS

We performed a retrospective review of the medical records of 95 high myopia patients (refractive error ≥ 6.00 diopters, axial length ≥ 26.0 mm) with mCNV. Patients were treated with anti-VEGF alone (group A) or anti-VEGF followed by PSR (group B). The following data were collected: refractive error, best corrected visual acuity (BCVA), ophthalmic fundus examination, ocular coherence tomography and ocular biometry at 12 and 24 months pre- and postoperatively. The primary outcomes were changes in pCRA and BCVA.

RESULTS

In 26 eyes of 24 patients, the mean pCRA size significantly increased from baseline (0.88 ± 1.69 mm2) to 12 months (1.57 ± 2.32 mm2, t = 3.249, P = 0.003) and 24 months (2.17 ± 2.79 mm2, t = 3.965, P = 0.001) postoperatively. The increase in perilesional pCRA in group B (n = 12) was 98.2% and 94.2% smaller than that in group A (n = 14) at 12 and 24 months (Beta 0.57 [95% CI 0.01, 191 1.13], P = 0.048). In group B, 7 eyes (58.3%) gained more than 2 lines of BCVA compared with only 4 eyes (28.6%) in group A at 24 months.

CONCLUSION

Anti-VEGF therapy followed by PSR achieved better outcomes than anti-VEGF therapy alone in controlling the development of myopic maculopathy in mCNV and may constitute a better treatment option by securing a better long-term VA outcome.

Observation of the effect of posterior scleral reinforcement combined with orthokeratology and 0.01% atropine in the treatment of congenital myopia: a case report

BACKGROUND

Myopia has recently emerged as a significant threat to global public health. The high and pathological myopia in children and adolescents could result in irreversible damage to eye tissues and severe impairment of visual function without timely control. Posterior scleral reinforcement (PSR) can effectively control the progression of high myopia by limiting posterior scleral expansion, improving retrobulbar vascular perfusion, thereby stabilizing the axial length and refraction of the eye. Moreover, orthokeratology and low concentrations of atropine are also effective in slowing myopia progression.

CASE PRESENTATION

A female child was diagnosed with binocular congenital myopia and amblyopia at the age of 3 and the patient's vision had never been rectified with spectacles at the first consultation. The patient's ophthalmological findings suggested, high refractive error with low best corrected visual acuity, longer axial length beyond the standard level of her age, and fundus examination suggesting posterior scleral staphyloma with weakened hemodynamics of the posterior ciliary artery. Thereby, PSR was performed to improve fundus health and the combination of orthokeratology and 0.01% atropine were performed to control the development of myopia. Following up to 8 years of clinical treatment and observations, the progression of myopia could be well controlled and fundus health was stable.

CONCLUSION

In this report, 8-year of clinical observation indicated that PSR could improve choroidal thickness and hemodynamic parameters of the retrobulbar vessels, postoperative orthokeratology combined with 0.01% atropine treatment strategy may be a good choice for myopia control effectively.

Investigation of Choroidal Blood Flow and Thickness Changes Induced by Near Work in Young Adults

PURPOSE

This research aimed to determine the effects of near work on macular choroidal blood flow and thickness in young adults.

METHODS

A total of 109 participants (19-28 years old) were recruited from Capital Medical University in China. The participants spent 40 min reading a book text at a distance of 33 cm. Swept-source optical coherence tomography/optical coherence tomography angiography (SS-OCT/OCTA) was performed to measure the changes in choriocapillaris perfusion area (CCPA) and choroidal thickness (ChT) after 40 min of near work. The SS-OCT/OCTA data covered an area of 6 mm × 6 mm, which centered on the fovea.

RESULTS

The baseline ChT and CCPA before near work were negatively correlated with AL, while positively correlated with the magnitude of spherical equivalent (p < .001). Total CCPA decreased significantly by 6 mm × 6 mm macular area after near work compared to that before near work (24.26 ± 1.96 vs. 24.63 ± 1.61 mm2, p<.001). The macular ChT was lower after 40 min of reading than that before 40 min of reading, but no significant difference was observed (302.25 ± 77.69 vs. 304.92 ± 79.73 μm, p = .078). The extent of choroidal thinning was significantly positively correlated with the magnitude of CCPA reduction (p < .001). The decline in CCPA after near work was significantly positively correlated with axial length (AL; p < .001).

CONCLUSION

This study demonstrated that near work significantly decreased CCPA. The extent of CCPA reduction after near work was associated with higher severity of myopia and choroidal thinning. The baseline CCPA and ChT decreased gradually with AL.

Evidence of vascular involvement in myopia: a review

The benign public perception of myopia (nearsightedness) as a visual inconvenience masks the severity of its sight-threatening consequences. Myopia is a significant risk factor for posterior pole conditions such as maculopathy, choroidal neovascularization and glaucoma, all of which have a vascular component. These associations strongly suggest that myopic eyes might experience vascular alterations prior to the development of complications. Myopic eyes are out of focus because they are larger in size, which in turn affects their overall structure and function, including those of the vascular beds. By reviewing the vascular changes that characterize myopia, this review aims to provide an understanding of the gross, cellular and molecular alterations identified at the structural and functional levels with the goal to provide an understanding of the latest evidence in the field of experimental and clinical myopia vascular research. From the evidence presented, we hypothesize that the interaction between excessive myopic eye growth and vascular alterations are tipping-points for the development of sight-threatening changes.

Clinical Feasibility and Safety of Scleral Collagen Cross-Linking by Riboflavin and Ultraviolet A in Pathological Myopia Blindness: A Pilot Study

INTRODUCTION

To investigate the feasibility and safety of scleral ultraviolet A (UVA) cross-linking (scleral CXL) on pathologically blindness.

METHODS

This was a prospective, observational clinical study. Five patients with monocular blindness due to pathological myopic maculopathy were enrolled. Eyes with best corrected visual acuity (BCVA) under 0.05 were defined as experimental eyes. The fellow eyes were defined as control eyes. Patients first underwent posterior scleral reinforcement (PSR) surgery in the control eye. Thereafter, scleral CXL surgery was performed in the experimental eye on the same day. Visual acuity, BCVA, slit lamp biomicroscopic examination, intraocular pressure measurement, corneal specula microscopies, axis length measurement, funduscopy with pupil dilation, color fundus photography, full-field flash electroretinography, optical coherence tomography, and color Doppler flow imaging were performed at baseline, 1 week, 1 month, 3 months, 6 months, and 12 months after surgery.

RESULTS

No signs of inflammation were observed after operation and throughout the follow-up period. Retinoschisis was improved, while choroidal neovascularization fibrosis and retinal and choroidal atrophy were unchanged after scleral CXL. There were no statistically significant differences in the ophthalmic artery, central retinal artery, and posterior ciliary artery parameters of color Doppler flow imaging or in retinal thickness, within experimental and control eyes, at baseline, 1 week, 1 month, 3 months, or 12 months (P > 0.05).

CONCLUSIONS

This pilot study verified the feasibility and safety of scleral CXL on human blindness. The UVA-CXL on the sclera of human eyes seems to have the same effect as PSR in preventing progressive pathological myopia in the future.

TRIAL REGISTRATION

Chinese Clinical Trial Registry (ChiCTR2100042422).

Posterior scleral reinforcement for the treatment of myopic traction maculopathy

Background

This study aimed to investigate the clinical effectiveness of posterior scleral reinforcement(PSR) for the treatment of myopic traction maculopathy (MTM).

Methods

This was a prospective study of 32 eyes from 20 patients with MTM treated with PSR using genipin-cross-linked donor sclera. The length of the scleral strip used for the surgery was designed to be 1.5-times the axial length of the eye, whereas its width was 0.4-times the axial length of the eye. The optical coherence tomography images, spherical equivalent of refractive error, axial length, best corrected visual acuity, electroretinogram findings, and intraocular pressure of the patients were assessed postoperatively.

Results

The mean duration of follow-up was 17.80 ± 8.74 months. The differences between the spherical equivalent of refractive error, best corrected visual acuity, axial length, and electroretinogram findings recorded preoperatively and those measured postoperatively were statistically significant (p < 0.05). The final reduction in axial length was 1.64 ± 0.85 mm. At the end of the follow-up, optical coherence tomography showed essential foveal reattachment in 30 eyes (93.75%), partial reattachment in two eyes (6.25%), and closure of macular holes in seven eyes (77.78%). No retinal detachment, vitreous haemorrhage, or other serious complications occurred following the surgery.

Conclusions

Posterior scleral reinforcement with genipin-cross-linked sclera showed safe and effective outcomes for the treatment of MTM during a follow-up period of at least one year.

Trial registration

11\12\2018, ChiCTR1800020012.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12886-022-02497-6.

Advances in OCT Imaging in Myopia and Pathologic Myopia

Advances in imaging with optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA) technology, including the development of swept source OCT/OCTA, widefield or ultra-widefield systems, have greatly improved the understanding, diagnosis, and treatment of myopia and myopia-related complications. Anterior segment OCT is useful for imaging the anterior segment of myopes, providing the basis for implantable collamer lens optimization, or detecting intraocular lens decentration in high myopic patients. OCT has enhanced imaging of vitreous properties, and measurement of choroidal thickness in myopic eyes. Widefield OCT systems have greatly improved the visualization of peripheral retinal lesions and have enabled the evaluation of wide staphyloma and ocular curvature. Based on OCT imaging, a new classification system and guidelines for the management of myopic traction maculopathy have been proposed; different dome-shaped macula morphologies have been described; and myopia-related abnormalities in the optic nerve and peripapillary region have been demonstrated. OCTA can quantitatively evaluate the retinal microvasculature and choriocapillaris, which is useful for the early detection of myopic choroidal neovascularization and the evaluation of anti-vascular endothelial growth factor therapy in these patients. In addition, the application of artificial intelligence in OCT/OCTA imaging in myopia has achieved promising results.

Choroidal changes in carotid stenosis patients after stenting detected by swept-source optical coherence tomography angiography

BACKGROUND

Carotid artery stenosis (CAS) patients show reduced blood flow in the ophthalmic artery. This study aimed to assess the changes in the choriocapillaris and choroidal thickness in patients with unilateral carotid artery stenosis after carotid stenting using swept-source optical coherence tomography (SS-OCT)/swept-source optical coherence tomography angiography (SS-OCTA).

METHODS

Fifty-three mild to moderate CAS patients and 40 controls were enrolled in this study. All participants underwent digital subtraction angiography (DSA) and SS-OCT/SS-OCTAA imaging before and 4 days after carotid artery stenting. SS-OCTA was used to image and measure the perfusion of the choriocapillaris (mm2) while SS-OCT was used to image and measure the choroidal thickness (µm). The stenosed side was described as the ipsilateral eye while the other side was the contralateral eye.

RESULTS

Choroidal thickness was significantly thinner (P = 0.024) in CAS when compared with controls. Ipsilateral eyes of CAS patients showed significantly thinner (P = 0.008) choroidal thickness when compared with contralateral eyes. Ipsilateral eyes of CAS patients showed thicker (P = 0.027) choroidal thickness after carotid artery stenting while contralateral eyes showed thinner choroidal thickness (P = 0.039).

CONCLUSIONS

Our report suggests that in vivo quantification of the choroid with the SS-OCT/SS-OCTA may allow monitoring of CAS and enable the assessment of purported treatments.

Retinal and Choroidal Vascular Perfusion and Thickness Measurement in Diabetic Retinopathy Patients by the Swept-Source Optical Coherence Tomography Angiography

Purpose

To observe the changes in retinal and choroidal microstructures in patients with different stages of diabetic retinopathy (DR) and to evaluate the vascular perfusion of retina and choroid retinal thickness, retinal and choroidal vessel density by the swept-source optical coherence tomography angiography (SS-OCTA).

Methods

Subjects were divided into three groups: healthy control group (30 cases, 51 eyes), non-proliferative diabetic retinopathy (NPDR, 42 cases, 71 eyes) and proliferative diabetic retinopathy (PDR, 31 cases, 53 eyes). The area of the foveal avascular zone (FAZ), retinal and choroidal vascular perfusion, and the deep vascular complexes, including the intermediate capillary plexus (ICP) and deep capillary plexus (DCP) within the radius of 3, 6, 9, and 12 mm around the fovea were measured by SS-OCTA.

Results

Compared with the healthy control group, DR patients presented significantly increased fovea avascular area, while vessel density (VD) in the ICP and DCP, vascular perfusion rate, and the retinal thickness were considerably decreased. There were significant differences in the retinal thickness, ICP, and DCP vessel densities between the control and NPDR groups, or control and PDR groups, or PDR and NPDR groups. The deep vascular perfusion rate also significantly differed between the control and PDR groups, but there was no significant difference between the PDR and NPDR groups. The choroidal perfusion exhibited significant differences across different areas and amongst the three groups. Furthermore, the choroidal thickness showed a significant difference between the PDR and NPDR groups.

Conclusion

Our results showed significant differences in the area of the avascular fovea and the VD of deep vascular complexes between DR patients and healthy control subjects. Moreover, there were significant differences in retinal VD, especially in the deep-retinalregions, choroidal perfusion, and the volume of large vessel choroid in DR patients with different degrees of disease severity. Notably, SS-OCTA provided in-depth information for detecting the potential VD damage in DR patients caused by a multitudeof factors.