CHOROIDAL THICKNESS AFTER INTRAARTERIAL CHEMOTHERAPY FOR RETINOBLASTOMA

Assessment of Retinal Microvasculature and Choroidal Vascularity After Intra-arterial Chemotherapy for Retinoblastoma

PURPOSE

To evaluate changes in retinal microvascular density and choroidal vascularity in patients with retinoblastoma (RB) after intra-arterial chemotherapy (IAC).

DESIGN

Retrospective clinical cohort study.

METHODS

This study included 12 unilateral RB eyes treated with IAC (RB tumor), 12 contralateral normal eyes (RB fellow), and 12 healthy controls. The macular retinal thickness and retinal microvascular structure, including the foveal avascular zone (FAZ) area, macular and peripapillary superficial vessel density (SVD), and deep vessel density (DVD), were measured by optical coherence tomography angiography (OCTA). The choroidal thickness (ChT) and choroidal vascularity, including total choroidal area (TCA), luminal area (LA), stromal area (SA), and choroidal vascularity index (CVI), were measured by spectral-domain optical coherence tomography (SD-OCT). A comparison among the 3 groups was conducted, and the correlations among the parameters were analyzed.

RESULTS

Among the 3 cohorts, the foveal retinal thickness, SVD, DVD, ChT, TCA, LA, SA, and CVI were significantly lower in RB tumor compared to RB fellow and the control eyes (all P < .01). There were no significant differences in the parameters between the contralateral and control eyes. The correlation analyses indicated a significant negative correlation between the total melphalan dose and foveal and parafoveal DVD, ChT, and LA.

CONCLUSIONS

The retinal microvascular density and choroidal vascularity were lower in unilateral RB treated with IAC, and seemed to be related to the total melphalan dose. There were no measurable changes in the contralateral eyes.

Retinal microvasculature observations of fellow eyes after intra-arterial chemotherapy for unilateral retinoblastoma using optical coherence tomography angiography

Purpose

To investigate the characteristics of the retinal microvasculature of the fellow eyes in patients with unilateral retinoblastoma (RB) after intra-arterial chemotherapy (IAC) through optical coherence tomography angiography.

Methods

This retrospective study enrolled 11 fellow eyes of patients with unilateral RB receiving IAC (group I), nine fellow eyes of patients with unilateral RB receiving IAC and intravenous chemotherapy (IVC) (group II), and 14 age-matched normal eyes (control group). Optical coherence tomography angiography was performed on all individuals. Vascular density of superficial capillary plexus and deep capillary plexus (DCP), foveal avascular zone related parameters, and retinal thickness were measured and compared among the three groups.

Results

There was no statistical difference in age and logMAR visual acuity among the three groups. Compared with the control group, the vascular density of the DCP was lower in group I and II. Decreased vascular density of FD-300 and thinner thickness of outer plexus layer to Bruch's membrane were detected in group II compared with the control group. The vascular density and retinal thickness showed no differences between group I and II.

Conclusion

The decreased vascular density in the DCP without measurable visual impairment was observed in fellow eyes after IAC or IAC + IVC for unilateral RB. Further studies with a larger sample would be necessary to determine the clinical significance of these findings.

Choroidal occlusive vasculopathy after intraarterial chemotherapy: MRI findings

PURPOSE

To evaluate magnetic resonance imaging (MRI) findings in patients suffering choroidal occlusive vasculopathy (COV) after intra-arterial chemotherapy (IAC) for retinoblastoma.

METHODS

A retrospective study of 37 eyes of 34 patients receiving IAQ between 2016 to 2021 as primary or secondary treatment for retinoblastoma was conducted. Twenty-two patients received systemic chemotherapy with carboplatin, vincristine and etoposide. The rest received IAC as primary treatment. The drugs administered were melphalan (3-4mg), carboplatin (40mg) plus topotecan (20mg). The patients were examined under general anaesthesia every month to observe tumor regression and possible complications of the treatment. For the patients with COV an MRI was obtained to analyse the choroidal thickness and axial ocular length.

RESULTS

A COV was observed in 5 of the 37 eyes receiving IAC (13,51%), all of them with a complete sectorial choroidopathy not sparing the fovea (grade 2). In 4 of the 5 patients the choroidal thickness was decreased and in three cases the size of the eye which presented COV was clearly smaller than the contralateral eye. Tumor control was archived in all 5 patients.

CONCLUSION

In our cases COV was associated with reduction of thinning of choroid and eye length in the MRI. A new classification maybe needed to correlate better with the severity of the complication affecting the fovea. Although early results generally are favorable to the use of IAC, longer follow up and scrupulous documentation of side effects will be necessary to know the true role of IAC for retinoblastoma.

Quantitative evaluation of retinal microvasculature and retrobulbar vessels after intravenous chemotherapy for retinoblastoma

Backgroud

To evaluate the changes in retinal microvasculature and retrobulbar blood flow, using optical coherence tomography angiography (OCTA) and Color Doppler imaging (CDI) after intravenous chemotherapy (IVC) in patients with retinoblastoma (RB).

Methods

This was a retrospective comparative case control series involving 30 patients. Ten bilateral RB patients that had a preserved eye with extramacular tumours (group I), 10 unilateral RB treated with IVC that had a normal fellow study eye (group II), and 10 age-matched healthy controls. The macular retinal thickness, foveal avascular zone (FAZ) area, and the macular and peripapillary retinal vessel densities (RVD) were measured. The peak systolic and end diastolic velocities of the ophthalmic, central retinal and posterior ciliary arteries were determined. A comparison among the three groups was conducted.

Results

Between the three cohorts, OCTA revealed no significant difference in FAZ area, superficial foveal and parafoveal RVD, deep parafoveal RVD and peripapillary RVD, (P > 0.05). By contrast, the mean deep foveal RVD, the full, inner and outer foveal and the parafoveal retinal thickness were significantly lower in group I compared with the controls, (P = 0.0329, 0.0153, 0.0311 0.0352, 0.0215). No significant difference in the blood flow velocities occurred in the retrobulbar circulation (P > 0.05).

Conclusions

In patients with retinoblastoma, OCTA did not detect significant changes of retinal thickness and vessel density in the eyes treated with IVC, but a slight reduction in retinal thickness and the deep foveal RVD seemed to occur in bilateral RB eyes. The retrobulbar blood flow parameters showed no measurable changes.

Choriocapillaris: Fundamentals and advancements

The choriocapillaris is the innermost structure of the choroid that directly nourishes the retinal pigment epithelium and photoreceptors. This article provides an overview of its hemovasculogenesis development to achieve its final architecture as a lobular vasculature, and also summarizes the current histological and molecular knowledge about choriocapillaris and its dysfunction. After describing the existing state-of-the-art tools to image the choriocapillaris, we report the findings in the choriocapillaris encountered in the most frequent retinochoroidal diseases including vascular diseases, inflammatory diseases, myopia, pachychoroid disease spectrum disorders, and glaucoma. The final section focuses on the development of imaging technology to optimize visualization of the choriocapillaris as well as current treatments of retinochoroidal disorders that specifically target the choriocapillaris. We conclude the article with pertinent unanswered questions and future directions in research for the choriocapillaris.

Risk Factors for Acute Choroidal Ischemia after Intra-arterial Melphalan for Retinoblastoma: The Role of the Catheterization Approach

PURPOSE

To identify risk factors for acute choroidal ischemia (ACI) after intra-arterial chemotherapy (IAC) for retinoblastoma.

DESIGN

Retrospective cohort study.

PARTICIPANTS

Two hundred twenty patients (248 eyes) treated with IAC in Lausanne between November 2008 and September 2019 (665 procedures). All patients were evaluated on a monthly basis with fundus photography and fluorescein angiography before and after each IAC injection.

METHODS

Acute choroidal ischemia, defined as any new choroidal ischemia clinically diagnosed within 35 days after an IAC injection, were noted. Eyes with choroidal complications diagnosed later than 35 days after the last IAC injection (n = 7) or those for which the status of the choroid was not assessable (n = 35) were excluded. Specific procedure parameters and treatment regimens were compared between the group of eyes with and without ACI.

MAIN OUTCOME MEASURES

Procedure-related risk factors for ACI after IAC injection and visual acuity assessment in the group of eyes with ACI.

RESULTS

Acute choroidal ischemia developed in 35 of 206 included eyes after a mean of 2 injections. No differences were found between the two study groups regarding age at first IAC injection, disease grouping at diagnosis, previously administered treatments, number of IAC injections, drug dose, mean injection time, injection method (pulsatile vs. continuous), or concomitant intravitreal melphalan use. Treatment regimen (melphalan vs. combined melphalan plus topotecan; P < 0.05), catheterization route (internal carotid artery vs. external carotid or posterior communicating artery; P < 0.001), and catheterization type (occlusive into the ophthalmic artery [OA] vs. nonocclusive; P < 0.001) were included in multivariate analysis, and occlusive catheterization was identified as an independent risk factor for ACI (P < 0.001). In the subgroup undergoing an occlusive procedure, placement of the catheter tip into the OA distal third versus medial and proximal thirds (P = 0.04) and a mean catheter diameter-to-OA lumen ratio of 0.6 or more (P < 0.001) were correlated significantly with ACI. Complete vision loss was noted in 27% of the eyes with ACI that were old enough for visual assessment (n = 9/33), whereas 33% maintained a useful vision ranging between 0.1 and 0.8 (n = 11/33).

CONCLUSIONS

Catheterization of the OA should be attempted from an ostial position or an external carotid approach to minimize the risk of potentially vision-threatening choroidal complications.

[Retinoblastoma]

Retinoblastomas represent 6% of all malignant tumors in children under 5 years old, which untreated lead to blindness in the affected eye and death due to metastases. The main symptoms are leukocoria and strabismus, which if possible, always necessitate a clarification within 1 week for exclusion of a retinoblastoma. The most frequent differential diagnoses are Coats' disease and persistent fetal vasculature (PFV) as well as other intraocular tumors, in particular astrocytomas. Systemic chemotherapy, if necessary in combination with laser hyperthermia, local chemotherapy and brachytherapy are the most important methods for eye-preserving treatment. Advanced cases mostly necessitate enucleation.

Intra-arterial chemotherapy in retinoblastoma - A paradigm change

Intra-arterial chemotherapy (IAC), also known as superselective ophthalmic artery chemotherapy or chemosurgery, is currently widely accepted as one of the primary treatment modalities for intraocular retinoblastoma worldwide. Following the introduction of the technique in 1998, IAC has evolved over the past decades to be safer and more effective. Accumulated evidence shows that IAC is more effective in providing eye salvage in group D and E retinoblastoma as compared to conventional systemic intravenous chemotherapy (IVC). In contrast to IVC, IAC has the added benefits of reduced overall treatment duration and minimal systemic toxicity. This review provides a comprehensive update on the history, technique, indications, contraindications, and outcome of IAC. We have also identified the strengths, weaknesses, opportunities and threats (SWOT analysis) of the technique in this review.

Conservative management of retinoblastoma: Challenging orthodoxy without compromising the state of metastatic grace. "Alive, with good vision and no comorbidity"

Retinoblastoma is lethal by metastasis if left untreated, so the primary goal of therapy is to preserve life, with ocular survival, visual preservation and quality of life as secondary aims. Historically, enucleation was the first successful therapeutic approach to decrease mortality, followed over 100 years ago by the first eye salvage attempts with radiotherapy. This led to the empiric delineation of a window for conservative management subject to a "state of metastatic grace" never to be violated. Over the last two decades, conservative management of retinoblastoma witnessed an impressive acceleration of improvements, culminating in two major paradigm shifts in therapeutic strategy. Firstly, the introduction of systemic chemotherapy and focal treatments in the late 1990s enabled radiotherapy to be progressively abandoned. Around 10 years later, the advent of chemotherapy in situ, with the capitalization of new routes of targeted drug delivery, namely intra-arterial, intravitreal and now intracameral injections, allowed significant increase in eye preservation rate, definitive eradication of radiotherapy and reduction of systemic chemotherapy. Here we intend to review the relevant knowledge susceptible to improve the conservative management of retinoblastoma in compliance with the "state of metastatic grace", with particular attention to (i) reviewing how new imaging modalities impact the frontiers of conservative management, (ii) dissecting retinoblastoma genesis, growth patterns, and intraocular routes of tumor propagation, (iii) assessing major therapeutic changes and trends, (iv) proposing a classification of relapsing retinoblastoma, (v) examining treatable/preventable disease-related or treatment-induced complications, and (vi) appraising new therapeutic targets and concepts, as well as liquid biopsy potentiality.

Retinal reattachment and ERG recovery after ophthalmic artery chemosurgery for advanced retinoblastoma in eyes with minimal baseline retinal function

AIM

To report retinal function outcomes after ophthalmic artery chemosurgery (OAC) for advanced retinoblastoma (RB) in eyes with minimal pretreatment retinal function.

METHODS

For 72 advanced RB eyes with baseline electroretinograms (ERGs) indistinguishable from noise ('extinguished') or flicker ERG amplitudes <25 µV ('poor'), ERGs were obtained before OAC and at 3 months, 1 year and 2 years after OAC. Presence of baseline retinal detachments (RDs) and their subsequent resolution or persistence was also noted.

RESULTS

At 3 months, 1 year and 2 years post-OAC, 'extinguished' eyes showed 9/15, 4/11 and 2/6 detectable ERGs, respectively, and 'poor' eyes showed 19/55, 14/30 and 8/18 ERGs exceeding 25 μV, respectively. Correlations between baseline and post-OAC ERGs were poor; however, good correlation (R²) existed between ERGs post-OAC at 3 months and 1 year (0.749), at 3 months and 2 years (0.773) and at 1 year and 2 years (0.771). Overall, 49/70 eyes presented with RD; 29 RDs resolved 3 months post-OAC, with an average ERG change of +20.6 μV. Eyes with persistent RD had an average ERG change of -2.2 μV. No eyes underwent ≥25 μV change without RD resolution.

CONCLUSIONS

Minimal baseline ERGs do not preclude significant recovery of retinal function after OAC. Good correlation exists between ERG outcomes at 3 months and those at subsequent follow-ups, suggesting that ERG amplitudes at 3-month post-OAC can prognosticate longer term retinal function, and that improvement is durable. For eyes presenting with RD, RD resolution is necessary but not sufficient for significant (≥25 μV) increases in ERG amplitudes.