Diagnosis and Management of Conjunctival and Corneal Intraepithelial Neoplasia Using Ultra High-Resolution Optical Coherence Tomography

It Is All About the Angle: A Clinical and Optical Coherence Tomography Comparison of Corneal Ocular Surface Squamous Neoplasia and Corneal Pannus

PURPOSE

The aim of this study was to compare clinical characteristics and high-resolution optical coherence tomography (HR-OCT) findings between corneal ocular surface squamous neoplasia (OSSN) and corneal pannus.

METHODS

Retrospective study of 9 individuals, 3 with lesions histologically confirmed to be OSSN, 3 with lesions histologically confirmed to be pannus, 1 with lesions histologically confirmed to be OSSN followed by pannus, and 2 with long-standing, nonchanging lesions clinically diagnosed as pannus. All individuals presented to the Miami Veterans Affairs Medical Center eye clinic or Bascom Palmer Eye Institute between 2015 and 2023. Clinical characteristics and HR-OCT findings were evaluated and compared.

RESULTS

Mean age of the population was 72.8 ± 5.1 years, 100% self-identified as male, 100% as White, and 11.1% as Hispanic. Clinically, all lesions appeared as whitish, opalescent, variably vascularized opacities extending from the limbus. None of the OSSN cases had vessels that extended to the border, whereas 4 cases of pannus (67%) had at least 1 vessel that reached the border. On HR-OCT, epithelial hyperreflectivity was observed in all cases of OSSN and pannus. Epithelial thickening was observed in all cases of OSSN, but in none of the cases of pannus. An important distinction between the 2 groups was the transition between normal and abnormal epithelium. All cases of OSSN had a vertical transition, whereas all cases of pannus had an angled transition.

CONCLUSIONS

Corneal OSSN and corneal pannus can both present with clinical findings of an opalescent lesion and may have overlapping findings on HR-OCT. Although both entities may show epithelial hyperreflectivity on HR-OCT, OSSN demonstrates an abrupt transition at a vertical, 90 degrees angle perpendicular to the Bowman layer, whereas pannus appears as an angled transition around 45 degrees. Therefore, the angle of transition between normal and abnormal epithelium can be useful in distinguishing between the 2 entities.

Conjunctival keratoacanthoma: a clinical and histopathological case series

OBJECTIVE

To present a series of conjunctival keratoacanthomas and provide clinical, histopathological, immunohistochemical, and imaging results that characterize this rare entity.

METHODS

A retrospective chart review of records from 2005 to 2023 from the Florida Lions Ocular Pathology Laboratory was conducted. Nine patients with histologically proven conjunctival keratoacanthoma were identified. Data extracted includes demographics, clinical history, diagnostic testing, histopathological and immunohistochemical testing, treatment modalities, and recurrences.

RESULTS

Patients' mean age was 55.2 ± 21.1 years (range: 22-83). 77.8% (7/9) of patients were male. 55.6% (5/9) were Hispanic. 55.6% of lesions (5/9) were in right eyes. 55.6% of lesions (5/9) were on the temporal, bulbar conjunctiva. The lesions were rapidly growing, with mean onset time of 4.71 ± 3.30 weeks (range: 2-12). High-resolution anterior segment optical coherence tomography of three lesions revealed hyper-reflective, thickened epithelium with abrupt transition between normal and abnormal epithelium. Underlying disorganized subepithelial tissue was noted. However, the overlying abnormal epithelium caused considerable shadowing, which obscured subepithelial structures. Prominent, keratin-filled, cup-shaped lesions with faulty maturational sequencing that extend full thickness, variably pale cytoplasm, and foci of dyskeratosis and hyperkeratosis were present on all lesions' histopathology. All lesions were surgically excised, but two demonstrated partial spontaneous resolution before surgery. Two patients were lost to follow-up; the remaining seven had no signs of recurrence at a of mean of 36.9 ± 45.4 months (range: 3 to 141 months) of follow-up.

CONCLUSIONS

Conjunctival keratoacanthomas are rare lesions of the ocular surface with distinct clinical, histopathologic, and diagnostic features.

Can high-resolution optical coherence tomography provide an optical biopsy for ocular surface lesions?

High-resolution optical coherence tomography (HR-OCT) has transformed the diagnosis and management of ocular surface lesions. Providing a detailed cross-sectional view of the cornea and conjunctiva, HR-OCT can be used to identify characteristic features of various benign and malignant ocular surface lesions, aiding in their diagnosis and guiding treatment. When incorporated into an ophthalmology clinic, HR-OCT provides morphological images of lesions in a noninvasive means, akin to an "optical biopsy". The characteristic HR-OCT features of several lesions have been well described in the literature, including for ocular surface squamous neoplasia, papilloma, melanoma, primary acquired melanosis, complexion associated melanosis, nevus, pterygium, pinguecula, lymphoma, and amyloidosis. HR-OCT can be used to differentiate between lesions with similar clinical features, lesions that co-exist on the same ocular surface, and atypically presenting lesions, such as pigmented ocular surface squamous neoplasia or amelanotic melanoma. The management of ocular surface lesions has been transformed by the implementation of HR-OCT, providing clinicians with the ability to monitor tumor response to topical chemotherapies, follow previously excised lesions for recurrence, and map out tumor borders intraoperatively. While there are some limitations to HR-OCT, including imaging of thick or deep lesions, it has become an essential tool for ocular oncologists in the management of ocular surface lesions.

Efficacy, safety and cost-effectiveness of 5-fluorouracil versus interferon α-2b as adjuvant therapy after surgery in ocular surface squamous neoplasia in a southern European tertiary hospital

PURPOSE

To analyze the efficacy, safety and cost-effectiveness of adjuvant therapy with 5-fluorouracil (5-FU) compared to interferon α-2b (IFNα-2b) after surgery in ocular surface squamous neoplasia (OSSN).

METHODS

Retrospective study that included patients diagnosed with OSSN, who underwent surgical excision followed by adjuvant therapy with IFN α-2b (Group A) or 5-FU (Group B), in a tertial referral hospital. Clinical data collected included: demographics, risk factors, appearance, size and location of the lesions, slit-lamp examination, anterior segment optical coherence tomography, iconography and histological classification of subtypes of OSSN. Costs derived from surgery and adjuvant therapy were noted. Resolution of the lesion, recurrences and adverse events were studied. Cost-effectiveness analysis was performed with the incremental cost-effectiveness index (CEI).

RESULTS

54 cases of 54 patients were included, with a mean age of 74.4 years (range 28-109). 30 were male (55.6%), and predominantly Caucasian (79.6%). The main risk factor was prolonged sun exposure (79.6%). Leukoplakic appearance (48.1%), location in bulbar conjunctiva (48.2%) and T3 (46.3%) stage were the most common clinical features. Histologically, the percentage of CIN I, CIN II, CIN III and SCC were 25.9%, 29.6%, 40.7% and 3.7%, respectively. Complete resolution was obtained in 74.1% and tolerance was overall positive. The cost was significantly higher for IFNα (1025€ ± 130.68€) compared to 5-FU (165.57€ ± 45.85 €) (p 0.001). The CEI was - 247.14€.

CONCLUSIONS

Both 5-FU and IFN α-2b are effective and present a good security profile as adjuvant therapies after surgery in OSSN. Although presenting slightly more ocular complications, 5-FU can be considered more cost-effective than IFN α-2b.

Case report: Clinical features and management outcomes of isolated corneal intraepithelial neoplasia

Purpose

To report clinical features and treatment outcome of three cases with isolated corneal intraepithelial neoplasia (CIN).

Methods

This case series presents 3 patients with isolated CIN. Data collected included, presenting signs and symptoms including vision, anterior segment examination, medical and surgical outcomes and signs and symptoms at lost post-treatment visit.

Results

Case 1 was a 45-year-old male who presented with an isolated grayish amoeboid corneal lesion which was excised with alcohol assisted epitheliectomy, he also received 6 cycles of topical mitomycin C (MMC) 0.02% and one injection of interferon alfa-2b with no recurrence during the 10-year follow-up period. Case 2 was 78-year-old male referred for a suspicious white corneal lesion which was completely excised, the patient also received 6 subconjunctival injections of interferon alpha-2b. However, the lesion recurred at 2.5-years post-treatment. Case 3 was a 63-year-old male patient who presented with an isolated corneal lesion that was excised using alcohol-assisted epitheliectomy, patient received four cycles of topical 5-fluorouracil with no recurrence at last follow-up visit at 6 months.

Conclusion

Isolated corneal intraepithelial neoplasia (CIN) is a rare entity with few reported cases in the literature. In this case series, we report long and short-term management outcomes of combined surgical and medical therapy for isolated CIN.

The role of anterior segment optical coherence tomography in the evaluation of the pterygium

BACKGROUND

To evaluate the ability of anterior segment optical coherence tomography (AS-OCT) to visualize the anatomic features of the pterygium and its invasion of the corneal layers.

METHODS

Seventy-five eyes of 54 patients diagnosed with pterygium were included. All subjects underwent complete ophthalmologic examinations, including AS-OCT. The limbus-apex distance, vertical height at the limbus, invasion of the Bowman's and stromal layers, and other morphologic structures of the pterygium tissue were analyzed.

RESULTS

The mean age of the patients was 49.67 ± 16.49 (20-85) years. The mean apex-limbus distance was 2548.37 ± 1026.32 (933-4597) μm, and the mean vertical height at the limbus was 4843.89 ± 1374.10 (1740-7784) μm. A space was observed beneath the pterygium tissue in 44 (58.67%) eyes. The mean width and height of this space were 1756.33 ± 560.22 (1009-3095) μm and 231.70 ± 85.88 (109-465) μm, respectively. Invasion of the Bowman's layer was apparent in 74 (98.67%) eyes, and invasion of the stromal layer was detected in 33 (44%) eyes. A hyperreflective layer was observed beneath the epithelial layer at the edge of the pterygium apex in 31 (41.33%) eyes. In 24 (92.31%) of the 26 advanced pterygium cases and 20 (40.82%) of the 49 early pterygium cases, a subpterygium space was found beneath the lesion (p = 0.0001).

CONCLUSION

AS-OCT enables measurement of the actual size and thickness of pterygia, assessment of invasion of the Bowman's and stromal layers of the cornea, and evaluation of the pterygium structure. Over half of the eyes exhibited space beneath the pterygium.

Corneal squamous neoplasia: masquerades and management outcomes at a rural eyecare centre

The authors describe two cases of corneal ocular surface squamous neoplasia (OSSN), presenting at our rural eyecare centre, which were initially misdiagnosed as viral epithelial keratitis and corneal pannus with focal limbal stem cell deficiency. Both the cases were refractory to initial treatment and corneal OSSN was suspected. Anterior segment-optical coherence tomography (AS-OCT) revealed a thickened, hyper-reflective epithelium with abrupt transition and an underlying cleavage plane, features typical of OSSN. Topical 1% 5-fluorouracil (5-FU) therapy was initiated and in two cycles (first case) to three cycles (second case), complete resolution was noted both clinically and on AS-OCT, with no significant side effects. Both patients are currently free of tumour at the 2-month follow-up period. The authors report the rare, atypical presentations of corneal OSSN, discuss the masquerades and highlight the role of primary topical 5-FU in managing corneal OSSN in limited resource settings.

Anterior segment optical coherence tomography in ocular surface tumours and simulating lesions

This study aims to systematically review the reported literature on the use of anterior segment optical coherence tomography (AS-OCT) in ocular surface tumours and simulating lesions. A systematic literature search was done using PubMed, Scopus, and Web of Science databases between January 2002 and December 2021. On AS-OCT, ocular surface squamous neoplasia typically demonstrate epithelial thickening, epithelial hyperreflectivity, and an abrupt transition between normal and abnormal epithelium. Conjunctival nevi usually show mildly hyperreflective epithelium of normal thickness, internal hyperreflectivity, and intralesional cysts which is the hallmark of this tumour. Primary acquired melanosis presents with normal thickness epithelium, basal epithelial hyperreflectivity, and absence of cysts. Conjunctival melanoma demonstrates hyperreflective normal/thickened epithelium, hyperreflective basal epithelium, internal hyperreflectivity, and absence of intralesional cysts. Conjunctival lymphoma shows homogenous, low-medium reflective subepithelial lesions with smooth borders, and dot-like infiltrates. Benign reactive lymphoid hyperplasia findings are similar to lymphoma but the infiltrates are more hyperreflective compared to lymphoma. Pterygium shows thickened conjunctival epithelium, epithelial hyperreflectivity, and subepithelial wedge-shaped hyperreflective tissue separated from the overlying epithelium by a cleavage plane. Pinguecula demonstrates mildly thickened epithelium and similar findings with pterygium but does not extend beyond the corneal limbus. This review shows that AS-OCT, as a noninvasive tool, has potential uses in the differential diagnosis of ocular surface tumours and simulating lesions. Major limitations of AS-OCT include limited visualization of the posterior border of thick, keratinized, and pigmented tumours and lack of assessment of large conjunctival tumours in a single cut.

Clinical and Optical Coherence Tomography Comparison Between Ocular Surface Squamous Neoplasia and Squamous Metaplasia

PURPOSE

The purpose of this study was to compare the clinical characteristics and high-resolution optical coherence tomography (HR-OCT) findings between corneal squamous metaplasia and ocular surface squamous neoplasia (OSSN).

METHODS

A retrospective case-control study of 8 patients, 4 with histologically confirmed squamous metaplasia and 4 with histologically confirmed OSSN, who presented to the Miami Veterans Administration Medical Center and Bascom Palmer Eye Institute between 2016 and 2020 was performed. Clinical characteristics, HR-OCT findings, and pathology were evaluated and compared.

RESULTS

Four patients with squamous metaplasia and 4 with OSSN were evaluated. In the metaplasia group, 75% were male, 2 were White, and 2 were Black. In the OSSN group, all 4 were White males. All lesions were opalescent and occurred at the limbus; however, the borders were more smooth and rounded in the metaplastic lesions compared with OSSN. HR-OCT findings were indistinguishable between the 2 groups.

CONCLUSIONS

There is overlap in clinical characteristics and HR-OCT findings between corneal squamous metaplasia and OSSN, highlighting one limitation of HR-OCT. As such, if a corneal opacity has some but not all HR-OCT findings of OSSN, squamous metaplasia should also be considered. A biopsy may be indicated to further evaluate and guide treatment.

Medical treatment for ocular surface squamous neoplasia

Ocular surface squamous neoplasia (OSSN) is the most common non-melanocytic tumour of the ocular surface. Surgical excision with wide margins using the "no-touch" method was originally the most popular treatment for OSSN. However, in the past two decades, the use of topical medications for OSSN treatment has gained a reputation amongst ophthalmologists for being an effective alternative to surgical excision. Furthermore, technological advancements, such as those seen in high-resolution optical coherence tomography (HR-OCT) for the anterior segment, have facilitated the diagnosis and monitoring of OSSN. When selecting a topical agent, interferon alpha-2b (IFNα-2b) and 5-fluorouracil (5-FU) are two of the gentlest medications used for OSSN and are often considered first line therapies due to their high-resolution rates and mild side effect profiles. Mitomycin C (MMC), on the other hand, has a highly toxic profile; therefore, while effective, in our hands it is considered as a second-line treatment for OSSN if the other modalities fail. In addition, newer and less studied agents, such as immune checkpoint inhibitors, retinoic acid, aloe vera, and anti-vascular endothelial growth factor have anti-neoplastic properties and have shown potential for the treatment of OSSN. We enclose an updated literature review of medical treatments for OSSN.

Anterior segment optical coherence tomography characteristics of conjunctival papilloma as compared to papilliform ocular surface squamous neoplasia

PURPOSE

To describe the anterior segment optical coherence tomography (AS-OCT) appearance of conjunctival papilloma and identify differentiating features from papilliform ocular surface squamous neoplasia (OSSN).

METHOD

A retrospective chart review of individuals clinically diagnosed with conjunctival papilloma (n = 10) or papilliform OSSN (n = 10) based on slit lamp features. Data on demographics, tumour characteristics, and primary treatment were collected. AS-OCT features were assessed including epithelial thickness and reflectivity, a corrugated epithelial surface, presence of an overhanging edge, presence of intrinsic spaces and posterior shadowing. Histopathology was available in 5 papilloma and 3 OSSN specimens.

RESULT

Overall, the majority of individuals in both groups were white males. OSSN lesions were more likely to involve the limbus (80% vs.10%, p = 0.005) and the bulbar conjunctiva (100% vs. 20%, p < 0.001) compared to papillomas. On AS-OCT, maximum epithelial thickness was thicker in papilloma compared to OSSN (936 ± 533 vs. 637 ± 207 µm, p = 0.009). The feature that best differentiated papilloma from OSSN was an overhanging edge (100% vs. 0%, p < 0.001), where the epithelial lesion was seen on top of underlying normal epithelium. Other features more common in papilloma compared to OSSN included a corrugated epithelial surface (70% vs.10%, p = 0.02), the presence of intrinsic spaces (100% vs. 50%, p = 0.03), and posterior shadowing (100% vs. 40%, p = 0.01).

CONCLUSION

AS-OCT shows differentiating features between papilloma and OSSN with an overhanging edge as a distinctive AS-OCT feature of papilloma.

How Can We Diagnose Ocular Surface Squamous Neoplasia With Optical Coherence Tomography?

AIM

We aimed to evaluate the effectiveness of optical coherence tomography (OCT) in the differential diagnosis of anterior segment diseases such as ocular surface squamous neoplasia (OSSN) and pterygium.

METHODS

Patients who were pre-diagnosed with either OSSN (21) or pterygium (19) between January 2020 and November 2022 were included in this retrospective study. Anterior segment photographs and anterior segment optical coherence tomography (AS-OCT) measurements were obtained from each patient. Excisional or incisional biopsy materials underwent pathological evaluation.

RESULTS

Preoperative AS-OCT images of the patients with OSSN showed similarities with histopathological specimens. Both ocular and pathological specimens appeared to have a thicker epithelial layer with a distinct change from healthy to neoplastic epithelium. Preoperative AS-OCT images of individuals with pterygium were also comparable with histopathological samples. Both pathological and AS-OCT images of the pterygium patients showed a normal thickness epithelium and a thickened subepithelial layer under the epithelium. The mean epithelial thickness measured with AS-OCT in OSSN patients was found to be 295.3 ± 111.3 µm, while it was 80.7 ± 43.4 µm in pterygium patients. The difference was statistically significant (P<0.001). The receiver operating characteristic (ROC) curve analysis revealed a cut-off value of 97 µm for the differential diagnosis of OSSN from pterygium, with a sensitivity of 100% and specificity of 94.7%.

CONCLUSIONS

AS-OCT can be used as a noninvasive diagnostic tool for the evaluation of ocular surface lesions. Its ability to distinguish between OSSN and pterygium is demonstrated by the statistically significant difference in epithelial thickness and the significant morphological association with histopathological findings.

Predicting demographic characteristics from anterior segment OCT images with deep learning: A study protocol

Introduction

Anterior segment optical coherence tomography (AS-OCT) is a non-contact, rapid, and high-resolution in vivo modality for imaging of the eyeball’s anterior segment structures. Because progressive anterior segment deformation is a hallmark of certain eye diseases such as angle-closure glaucoma, identification of AS-OCT structural changes over time is fundamental to their diagnosis and monitoring. Detection of pathologic damage, however, relies on the ability to differentiate it from normal, age-related structural changes.

Methods and analysis

This proposed large-scale, retrospective cross-sectional study will determine whether demographic characteristics including age can be predicted from deep learning analysis of AS-OCT images; it will also assess the importance of specific anterior segment areas of the eyeball to the prediction. We plan to extract, from SUPREME^®, a clinical data warehouse (CDW) of Seoul National University Hospital (SNUH; Seoul, South Korea), a list of patients (at least 2,000) who underwent AS-OCT imaging between 2008 and 2020. AS-OCT images as well as demographic characteristics including age, gender, height, weight and body mass index (BMI) will be collected from electronic medical records (EMRs). The dataset of horizontal AS-OCT images will be split into training (80%), validation (10%), and test (10%) datasets, and a Vision Transformer (ViT) model will be built to predict demographics. Gradient-weighted Class Activation Mapping (Grad-CAM) will be used to visualize the regions of AS-OCT images that contributed to the model’s decisions. The accuracy, sensitivity, specificity, and area under the receiver operating characteristic (ROC) curve (AUC) will be applied to evaluate the model performance.

Conclusion

This paper presents a study protocol for prediction of demographic characteristics from AS-OCT images of the eyeball using a deep learning model. The results of this study will aid clinicians in understanding and identifying age-related structural changes and other demographics-based structural differences.

Trial registration

Registration ID with open science framework:10.17605/OSF.IO/FQ46X.

Role of AS-OCT in Managing Corneal Disorders

Optical coherence tomography (OCT) is analogous to ultrasound biometry in the cross sectional imaging of ocular tissues. Development of current devices with deeper penetration and higher resolution has made it popular tool in clinics for visualization of anterior segment structures. In this review, the authors discussed the application of AS-OCT for diagnosis and management of various corneal and ocular surface disorders. Further, recent developments in the application of the device for pediatric corneal disorders and extending the application of OCT angiography for anterior segment are introduced.

Automated delineation of corneal layers on OCT images using a boundary-guided CNN

Accurate segmentation of corneal layers depicted on optical coherence tomography (OCT) images is very helpful for quantitatively assessing and diagnosing corneal diseases (e.g., keratoconus and dry eye). In this study, we presented a novel boundary-guided convolutional neural network (CNN) architecture (BG-CNN) to simultaneously extract different corneal layers and delineate their boundaries. The developed BG-CNN architecture used three convolutional blocks to construct two network modules on the basis of the classical U-Net network. We trained and validated the network on a dataset consisting of 1,712 OCT images acquired on 121 subjects using a 10-fold cross-validation method. Our experiments showed an average dice similarity coefficient (DSC) of 0.9691, an intersection over union (IOU) of 0.9411, and a Hausdorff distance (HD) of 7.4423 pixels. Compared with several other classical networks, namely U-Net, Attention U-Net, Asymmetric U-Net, BiO-Net, CE-Net, CPFnte, M-Net, and Deeplabv3, on the same dataset, the developed network demonstrated a promising performance, suggesting its unique strength in segmenting corneal layers depicted on OCT images.

Evaluation of pterygium severity with en face anterior segment optical coherence tomography and correlations with in vivo confocal microscopy

PURPOSE

To describe en face anterior segment optical coherence tomography (EF-OCT) characteristics of pterygia and their correlation with in vivo confocal microscopy (IVCM).

PATIENTS AND METHODS

In this observational case series, we prospectively included 21 eyes of 17 subjects with pterygium. All subjects underwent detailed ophthalmic examination, anterior segment photography, an ocular surface disease index (OSDI) questionnaire, IVCM, and EF-OCT. Eyes were divided into two groups according to pterygium severity (Modified Pterygium Classification System) and OSDI score. EF-OCT images for both groups were analyzed for surface area of Fuchs Patches (FP). The IVCM activity score was based on the number of inflammatory cells, blood vessels, activated keratocytes and the appearance of the cornea/pterygium at the head of the pterygium. The correlations between EF-OCT and IVCM images were then analyzed and compared in both groups.

RESULTS

EF-OCT permits clear visualization and evaluation of FPs and the border between the pterygium and the adjacent cornea. The severe pterygium group was characterized by irregular borders and larger FPs (0.13±0.06 mm² versus 0.06±0.02 mm² respectively) (P=0.003). The mean IVCM activity score was 2.36±0.81 in the severe pterygium group and 1.2±0.42 in the mild pterygium group (P=0.0013). There was a positive correlation between FP surface area and IVCM activity score. A larger FP surface area was associated with a higher activity score on IVCM.

CONCLUSION

EF-OCT allows good evaluation of pterygium extension, borders and FP surface area. EF-OCT analysis of pterygium could represent a simple, non-invasive and reproducible method to evaluate pterygium severity and activity.

Management of ocular surface squamous neoplasia: Bowman Club Lecture 2021

The gold-standard treatment for ocular surface squamous neoplasia (OSSN) has traditionally been surgical excision with wide margins and a no-touch technique. However, surgery may be associated with several unfavourable sequelae, as well as significant recurrence rates if margins are positive. In recent years, topical chemotherapy with 5-fluorouracil, interferon α-2b and mitomycin C have emerged as valuable agents capable of effectively treating OSSN with varying adverse effects. These medical treatment options usually present additional costs to the patient but can allow patients to avoid surgery with fewer long-term effects. Anterior segment high-resolution optical coherence tomography is an excellent tool for diagnosing and monitoring OSSN and can be a useful aid for both surgical and medical treatments of OSSN.

Case Series: High-resolution Optical Coherence Tomography as an Optical Biopsy in Ocular Surface Squamous Neoplasia

SIGNIFICANCE

Ocular surface squamous neoplasias are superficial tumors of the cornea and conjunctiva that can be sight threatening if neglected. Therefore, accurate noninvasive diagnostic modalities are needed.

PURPOSE

The purpose of this case series was to describe the hallmark features of ocular surface squamous neoplasia on high-resolution optical coherence tomography (HR-OCT) imaging and its use in the evaluation and management of superficial ocular tumors.

CASE SERIES

Five eyes of four patients with ocular surface squamous neoplasia are described. Whereas two eyes displayed the classic clinical features of ocular surface squamous neoplasia, three of the five eyes had more subtle atypical features. However, all shared features on HR-OCT of epithelial thickening and hyperreflectivity with abrupt transitions between normal and abnormal tissue, classic features of ocular surface squamous neoplasia. All lesions ultimately underwent incisional or excisional biopsy and were confirmed to be ocular surface squamous neoplasia on histopathology.

CONCLUSIONS

Ocular surface squamous neoplasia may present as a classic tumor but can also have subtle features or masquerade. Accurate methods to diagnose and manage patients with ocular surface squamous neoplasia are necessary. With recent advancements in technology, HR-OCT has been demonstrated to accurately identify ocular surface squamous neoplasia with the repeatable optical findings of (1) epithelial thickening, (2) epithelial hyperreflectivity, and (3) abrupt transition zone between normal and abnormal tissue. This case series demonstrates how HR-OCT can help provide an optical biopsy to guide appropriate diagnosis and management of this neoplastic lesion.

Spectrum of AS-OCT features of ocular surface tumors and correlation of clinico-tomographic features with histopathology: a study of 70 lesions

PURPOSE

To assess the correlation between clinical and anterior segment optical coherence tomographic (AS-OCT) details and histopathological changes in various ocular surface lesions.

METHODS

Prospective case series of 70 lesions in 65 patients.

RESULTS

AS-OCT revealed epithelial changes in OSSN (n = 19; 44%), squamous papilloma (n = 3; 60%), nevus (n = 1; 33%), epithelial hyperplasia (n = 1; 33%), granular dystrophy (n = 1; 100%) and granulation tissue (n = 1; 100%); subepithelial changes in chronic inflammation (n = 4, 100%), lymphoma (n = 3; 100%) and arteriovenous malformation (n = 1; 100%); combined epithelial and subepithelial changes in OSSN (n = 24; 56%), squamous papilloma (n = 2; 40%), PEH (n = 3; 100%), nevus (n = 2; 67%), epithelial hyperplasia (n = 2; 67%), solar elastosis (n = 1; 100%), lobular capillary hemangioma (n = 1; 100%) and sebaceous carcinoma (n = 1; 100%). Epithelial involvement on AS-OCT paralleled the histopathological findings in 98% (n = 69) and subepithelial involvement in 83% (n = 58). The correlation of clinico-tomographic diagnosis with histopathology diagnosis was seen in 77% (n = 54) lesions. Sensitivity and specificity of AS-OCT as a diagnostic tool for detection of epithelial involvement were 100% and 92% and for subepithelial involvement was 98% and 100%, respectively.

CONCLUSION

The correlation between AS-OCT and histopathology features determining epithelial and subepithelial involvement is excellent. It is a useful adjunctive tool for the diagnosis of ocular surface lesions.

The role of imaging technologies for ocular surface tumors

PURPOSE OF REVIEW

This review will discuss the utility of high-resolution anterior segment optical coherence tomography (HR-OCT), in-vivo confocal microscopy (IVCM) and ultrasound biomicroscopy (UBM) in characterizing and diagnosing various ocular surface tumors, namely ocular surface squamous neoplasia (OSSN), conjunctival lymphoma and conjunctival melanoma. The strengths and limitations of each imaging modality will be discussed along with the characteristics findings of each lesion on each imaging platform.

RECENT FINDINGS

HR-OCT can consistently be utilized in the clinic setting to distinguish between epithelial ocular surface tumors such as OSSN as compared with subepithelial tumors such as conjunctival lymphoma and conjunctival melanoma given their distinctive findings. IVCM can be used as an adjunct to HR-OCT to obtain cellular and surface characteristics, whereas UBM can be used to assess tumor depth and thickness for larger and highly pigmented lesions as well as to detect intraocular invasion.

SUMMARY

HR-OCT, IVCM and UBM are all helpful imaging modalities to diagnose and characterize various ocular surface tumors and can serve as valuable adjuncts to monitor treatment response and assess for recurrence ocular surface tumors.

Update on imaging modalities for ocular surface pathologies

Purpose of review

To discuss recent studies of imaging modalities for ocular surface pathologies.

Recent findings

Novel micro-ocular coherence tomography technology can produce high-resolution images of corneal cellular and nervous structures. Ocular coherence tomography angiography can aid in detecting early stage limbal stem cell deficiency. Several studies used in vivo confocal microscopy to evaluate corneal nerve metrics and morphology.

Summary

The applications of anterior segment optical coherence tomography, anterior segment optical coherence tomography angiography, ultrasound biomicroscopy, and in vivo confocal microscopy are useful technologies for imaging the ocular surface. Several studies have used artificial intelligence in combination with imaging technologies to create reliable and effective systems to detect and visualize ocular surface pathologies. AS OCT continues to be a key imaging tool and future development of μOCT technology may further enhance its utility.

Non-malignant conjunctival epithelial masses with ocular surface squamous neoplasia-like optical coherence tomography features

PURPOSE

To observe and describe the anterior segment optical coherence tomography features of limbally localised non-malignant epithelial mass lesions METHODS: Thirteen patients (age: 66.9 ± 16.3 years) with conjunctival mass suggesting ocular surface squamous neoplasia with biomicroscopic examination were imaged using anterior segment ocular coherence tomography (anterior segment optical coherence tomography)/Cirrus HD-OCT, Model 4000, Carl Zeiss Meditec, Inc., Dublin, CA, and Spectralis HRA + OCT system, Heidelberg Engineering, Vista, CA/. Cases with ocular surface squamous neoplasia-like anterior segment optical coherence tomography (hyperreflective, thickened epithelium and an abrupt transition from normal to abnormal) were included in the study. Maximal thickness of the epithelium was measured. Histological diagnosis was gained from an excisional or incisional biopsy or impression cytology specimens.

RESULTS

In six patients (age: 68.5 ± 15.4 years) with ocular surface squamous neoplasia-like anterior segment optical coherence tomography features, the histological diagnosis was other than ocular surface squamous neoplasia (papilloma, parakeratosis and a keratotic plaque with mild dysplasia), and ocular surface squamous neoplasia in seven cases (age: 65.6 ± 18.0 years). The maximal epithelial thickness was between 250 and 859 µm in non-ocular surface squamous neoplasia cases and between 252 and 596 µm in ocular surface squamous neoplasia cases.

CONCLUSION

Non-malignant epithelial lesions can mimic ocular surface squamous neoplasia on anterior segment optical coherence tomography.

Anterior segment optical coherence tomography and ultrasound biomicroscopy for measuring thickness of corneal and bulbar conjunctival tumours

BACKGROUND/OBJECTIVE

Anterior segment optical coherence tomography (AS-OCT) and ultrasound biomicroscopy (UBM) are two non-invasive imaging techniques used for the measurement of tumour thickness in corneal and bulbar conjunctival tumours. Histopathology (HP), however, remains the gold standard for the measurement of tumour thickness. The aim of this study was to determine whether AS-OCT and UBM are as accurate as HP for measuring tumour thickness.

METHODS

Forty-two corneal and bulbar conjunctival tumours were imaged using AS-OCT and UBM. Images were assessed and tumour thickness was measured. Eleven patients subsequently underwent surgical excision. All specimens were measured during histopathological analysis. The correlation of the thickness measurement on HP to AS-OCT and UBM was then statistically analysed. In cases where the tumour was not excised, thickness measurement comparisons between AS-OCT and UBM were analysed.

RESULTS

AS-OCT and UBM measurements of tumour thickness were found to be significantly positively correlated (p=<0.001), as were UBM and HP thickness measurements (p=0.031). HP and AS-OCT measurements, however, only showed a mild but non-significant positive correlation.

CONCLUSION

Both AS-OCT and UBM are useful techniques to image and measure the thickness of corneal and conjunctival bulbar tumours. While AS-OCT provides better details than UBM, it was more limited in visualising the posterior boundary of the tumour, particularly in malignant tumours. While thickness measurements of both methodologies were correlated, neither should yet be considered as replacements to the gold standard of HP.

Role of Conjunctival Ultraviolet Autofluorescence in Ocular Surface Squamous Neoplasia

Objective

To evaluate the adjunctive role of conjunctival autofluorescence in the management of ocular surface squamous neoplasia (OSSN).

Materials and Methods

Seventeen patients with clinically diagnosed OSSN were included. Morphological characteristics, type of OSSN, and autofluorescence photographs of the lesion were captured. Presence and area of conjunctival ultraviolet autofluorescence (CUVAF) were the main outcome measures.

Results

Overall, 17 patients with 15 (88%) primary and 2 (12%) recurrent OSSN were included. Common locations were temporal (n = 10), nasal (n = 5), and diffuse variety (n = 2). Morphologically, there were 4 (22.2%) nodular, 4 (22.2%) leucoplakic, 3 (16.7%) gelatinous, and 1 (5.5%) each of papillary, nodulo-ulcerative, and diffuse variety. Mixed morphology was present in 4 eyes (22.2%). Sixteen of 18 eyes (88.9%) with OSSN displayed autofluorescence on CUVAF images. The mean area of CUVAF was 15.82 mm² (10.77-19.59 mm²). Autofluorescence was reported in 8 eyes (44.4%) which had negative reports on impression cytology.

Conclusions

Conjunctival autofluorescence was seen in the majority of cases with OSSN, in spite of negative cytology reports. Our study demonstrates that CUVAF may serve as an effective ancillary, non-invasive, and resource-friendly tool for supplementing the clinical diagnosis of OSSN, especially in diffuse and recurrent lesions that are not amenable to surgical intervention.

Multi-modal Anterior Eye Imager Combining Ultra-High Resolution OCT and Microvascular Imaging for Structural and Functional Evaluation of the Human Eye

To establish complementary information for the diagnosis and evaluation of ocular surface diseases, we developed a multi-modal, non-invasive optical imaging platform by combining ultra-high resolution optical coherence tomography (UHR-OCT) with a microvascular imaging system based on slit-lamp biomicroscopy. Our customized UHR-OCT module achieves an axial resolution of ≈2.9 μm in corneal tissue with a broadband light source and an A-line acquisition rate of 24 kHz with a line array CCD camera. The microvascular imaging module has a lateral resolution of 3.5 μm under maximum magnification of ≈187.5× with an imaging rate of 60 frames/s, which is sufficient to image the conjunctival vessel network and record the movement trajectory of clusters of red blood cells. By combining the imaging optical paths of different modules, our customized multi-modal anterior eye imaging platform is capable of performing real-time cross-sectional UHR-OCT imaging of the anterior eye, conjunctival vessel network imaging, high-resolution conjunctival blood flow videography, fluorescein staining and traditional slit-lamp imaging on a single device. With self-developed software, a conjunctival vessel network image and blood flow videography were further analyzed to acquire quantitative morphological and hemodynamics parameters, including vessel fractal dimensions, blood flow velocity and vessel diameters. The ability of our multi-modal anterior eye imager to provide both structural and functional information for ophthalmic clinical applications was demonstrated on a healthy human subject and a keratitis patient.

High resolution anterior segment optical coherence tomography for differential diagnosis between corneo-conjunctival intraepithelial neoplasia and pterygium

OBJECTIVE

To assess if anterior segment optical coherence tomography (AS-OCT) is a noninvasive diagnostic method suitable to differentiate benign corneo-conjunctival lesions (pterygium) from premalignant lesions (corneo-conjunctival intraepithelial neoplasia, CIN).

MATERIAL AND METHODS

An observational, analytical and cross-sectional study was conducted in 22 eyes with conjunctival lesions clinically suspicious for pterygium and CIN during two years. Morphological differences between both lesions were studied with AS-OCT; epithelial thicknesses (EE) and extension length on corneal surface (GIC) were compared between both groups. A surgical excision of the lesion was performed for histopathological diagnosis.

RESULTS

Mean age of patients with pterygium (n=18) was 52.67±15 y.o and 74±12 y.o in subjects with CIN (n=4) (p<0.021). In pterygia, AS-OCT showed typical features (normal, thinning or slightly thickened EE; 77.4±26μm), in addition to an increase in wedge-shaped subepithelial tissue. Patients with CIN had a mean thickened EE (262.5±124μm) and strongly hyperreflective, with abrupt transition between normal and pathological epithelium. Analysis of EE between subjects with pterygium and CIN revealed statistically significant differences (p<0.002). ROC curve revealed a 100% sensitivity and specificity of OCT-SA in differentiation between CIN and pterygium, using 141μm as cutoff point of EE.

CONCLUSION

AS-OCT is a useful tool for the differentiation between pterygium and CIN able to provide typical morphological characteristics. An EE greater than 141μm in AS-OCT suggests a sensitivity and specificity of 100% for the diagnosis of CIN.

In-vivo Three-dimensional Characteristics of Bowman's Layer and Endothelium/Descemet's Complex Using Corneal Microlayer Tomography in Healthy Subjects

Purpose: To characterize the three-dimensional (3D) thickness profile and age-related changes of Bowman's layer (BL), and endothelium/Descemet's membrane (En/DM) complex among healthy individuals using Corneal Microlayer Tomography (CML-T), and to describe its repeatability and accuracy.Methods: Sixty-six eyes of 41 healthy volunteers; 27 eyes (< 40 years old), and 39 eyes (>40 years old) were imaged using HD-OCT. Automatic and manual segmentation of the corneal layers was performed, and 3D thickness maps were generated, using custom-built CML-T software. A regional analysis of mean thickness parameters between the 2 age groups was performed. A regression analysis was used to assess the correlation between age, and thickness maps. Intraclass Correlation Coefficients (ICC), Coefficients of Variation (COV), and Bland-Altman plots were used to assess the reliability of the repeated measurements in 198 locations.Results: CML-T successfully mapped the BL and En/DM in all included eyes. Thickness maps showed a significant increase in corneal thickness (CT), BL thickness (BMT), and En/DM complex thickness (DMT) toward the periphery with a mean difference 28 µm (p < .001), 1.1 µm (p < .001), and 1.4 µm (p < .001), respectively. There was a strong correlation between age and central DMT (r = 0.61; p < .001), while there was no correlation between age and both CT, and BMT. ICC values ranged from 0.9 (BMT) to 0.997 (DMT), and from 0.808 (BMT) to 0.979 (CT) for intraoperator repeatability of manual measurements, and the accuracy of auto matic measurements, respectively. COV values were lower than 7.5% in all cases.Conclusion: CML-T is a novel tool that can generate 3D-thickness maps of both BL and En/DM. CT, BMT, and DMT increase toward the periphery in healthy corneas. DMT increases with aging, while BMT does not. We also report excellent repeatability, accuracy and good agreement between automatic and manual measurements.

Corneal epithelial thickness profile in dry-eye disease

BACKGROUND/OBJECTIVES

To characterize and evaluate the use of corneal epithelial profile maps generated by an ultrahigh-resolution optical coherence tomography (UHR-OCT) in the diagnosis and management of dry-eye disease (DED).

SUBJECTS/METHODS

This prospective, interventional case-control study included 115 eyes of 71 subjects (52 DED and 19 controls) imaged using an UHR-OCT. Average, maximum, and minimum, range of corneal epithelial thicknesses were extracted from epithelial profile maps. Surface regularity was quantified using the range and variance of the epithelial thickness measured along a horizontal UHR-OCT scan. The variance of thickness measurements along a scan was named epithelial irregularity factor (EIF). Symptoms of 31 DED patients (55 eyes) were quantified by questionnaire and correlated to epithelial profile findings, fluorescein staining, tear breakup time, and Schirmer's test. Twenty-one DED eyes were administered autologous serum drops and follow-up UHR-OCT images were captured.

RESULTS

DED patients had a highly irregular corneal epithelial surface compared with controls. Epithelial thickness profile variance (EIF) and range were significantly higher in DED as compared with controls (5.79 vs. 0.77, p < 0.001 and 7.6 vs. 4.6 μm, p < 0.001). Both parameters were highly significantly correlated with questionnaire scores (EIF: r = 0.778; p < 0.001, range: r = 0.737; p < 0.001). Follow-up showed a statistically significant reduction in epithelial thickness profile variance and range of treated patients ( p < 0.001).

CONCLUSIONS

DED patients have irregular epithelial surface that can be quantified using UHR-OCT generated CEP maps. Epithelial thickness profile range and EIF correlate accurately with patients' symptoms and could be used to follow-up patients and response to treatment.

Use of High-Resolution Optical Coherence Tomography in the Surgical Management of Ocular Surface Squamous Neoplasia: A Pilot Study

PURPOSE

To evaluate whether high-resolution optical coherence tomography (HR-OCT) can detect histologic tumor margins of ocular surface squamous neoplasia (OSSN).

METHODS

Eight eyes of 8 patients with OSSN undergoing excision were studied prospectively. Immediately before surgery, the tumor was imaged using commercially available HR-OCT to identify the conjunctival margins of the neoplastic lesion. The tumor borders of the lesion determined by HR-OCT were mapped in relation to an anatomic reference point and transferred intraoperatively. The tumor was excised with 4-mm margins from the visible edge of the lesion with a "no-touch" technique. The specimens were sent for pathologic analysis and the histologic tumor margin was compared to the HR-OCT predicted tumor border.

RESULTS

Mean age of the 8 patients was 67 ± 9.9 years. Seven were male, 7 were white, and, ethnically, 3 were Hispanic. All 8 tumors were bulbar and in the exposure zone. Seven tumors were limbal. Corneal extension was present in 5. Mean tumor area was 17.5 ± 11.1 mm². Clinically, 2 of the tumors were leukoplakic, 1 papillomatous, and 3 gelatinous. A conjunctival tumor margin identified with the HR-OCT coincided with the pathologically confirmed margin mark in all eyes.

CONCLUSIONS

HR-OCT has the potential to predict histologic tumor margins in OSSN. Optical identification of tumor margins could potentially decrease the incidence of residual positive margins and minimize healthy tissue removal. Advances in HR-OCT technology and integration into a microscope for "real-time" imaging are needed to further improve this technique. NOTE: Publication of this article is sponsored by the American Ophthalmological Society.

Classification, diagnosis, and management of conjunctival lymphoma

Lymphoma is a malignant lymphoproliferative tumor that can involve the conjunctiva. Approximately 5-15% of all extranodal lymphomas are found in the ocular adnexal region, with approximately 25% of those involving the conjunctiva. Ninety-eight percent of conjunctival lymphomas arise from B-lymphocytes. The most common subtype of conjunctival lymphoma is extranodal marginal zone lymphoma (80%), followed by follicular lymphoma (8%), diffuse large B-cell lymphoma (3%) and mantle cell lymphoma (3%). Natural killer and T cells (NK/T) are rare causes of lymphoma. While most conjunctival lymphomas are localized to the ocular adnexa at the time of presentation, systemic examination and management are of key importance in the long-term care of the patient. This review outlines the classification, etiology, presentation, diagnosis, and management of conjunctival lymphoma. The novel use of high resolution optical coherence tomography, both as a diagnostic tool and as a means for ongoing evaluation during treatment, is illustrated. Treatment options discussed include external beam radiation, chemotherapy, immunotherapy, antibiotic therapy, and combination regimens. Future investigation of the etiology and pathogenesis of conjunctival lymphoma is expected to reveal opportunities for innovative and individualized therapeutic agents. Collaboration between multiple disciplines is key in the advancement of the field.

Automatic Segmentation of Corneal Microlayers on Optical Coherence Tomography Images

Purpose

To propose automatic segmentation algorithm (AUS) for corneal microlayers on optical coherence tomography (OCT) images.

Methods

Eighty-two corneal OCT scans were obtained from 45 patients with normal and abnormal corneas. Three testing data sets totaling 75 OCT images were randomly selected. Initially, corneal epithelium and endothelium microlayers are estimated using a corneal mask and locally refined to obtain final segmentation. Flat-epithelium and flat-endothelium images are obtained and vertically projected to locate inner corneal microlayers. Inner microlayers are estimated by translating epithelium and endothelium microlayers to detected locations then refined to obtain final segmentation. Images were segmented by trained manual operators (TMOs) and by the algorithm to assess repeatability (i.e., intraoperator error), reproducibility (i.e., interoperator and segmentation errors), and running time. A random masked subjective test was conducted by corneal specialists to subjectively grade the segmentation algorithm.

Results

Compared with the TMOs, the AUS had significantly less mean intraoperator error (0.53 ± 1.80 vs. 2.32 ± 2.39 pixels; P < 0.0001), it had significantly different mean segmentation error (3.44 ± 3.46 vs. 2.93 ± 3.02 pixels; P < 0.0001), and it had significantly less running time per image (0.19 ± 0.07 vs. 193.95 ± 194.53 seconds; P < 0.0001). The AUS had insignificant subjective grading for microlayer-segmentation grading (4.94 ± 0.32 vs. 4.96 ± 0.24; P = 0.5081), but it had significant subjective grading for regional-segmentation grading (4.96 ± 0.26 vs. 4.79 ± 0.60; P = 0.025).

Conclusions

The AUS can reproduce the manual segmentation of corneal microlayers with comparable accuracy in almost real-time and with significantly better repeatability.

Translational Relevance

The AUS can be useful in clinical settings and can aid the diagnosis of corneal diseases by measuring thickness of segmented corneal microlayers.

Detection of Malignancy in Ocular Surface Lesions by Inverse Spectroscopic Optical Coherence Tomography and Two-Photon Autofluorescence

Purpose

Advanced imaging is increasingly important in the diagnosis of ocular surface malignancy. Inverse spectroscopic optical coherence tomography (ISOCT) and two-photon autofluorescence microscopy (2P-AF) are emerging techniques capable of quantifying ultrastructural and metabolic changes, respectively. We aimed to detect malignancy in ocular surface lesions using ISOCT and 2P-AF.

Methods

Portions of excised specimens from patients undergoing conjunctival biopsy at Boston Medical Center were imaged by ISOCT and/or 2P-AF, and submitted for histologic diagnosis. Lesions were categorized as malignant, premalignant (with dysplasia) or benign. ISOCT and 2P-AF findings were compared between categories.

Results

Fourteen specimens from 13 patients were collected. The IS-OCT marker D was 2.2-fold higher in combined malignant and premalignant (4.27 ± 0.28, n = 3) versus benign (1.92 ± 0.26, n = 11) lesions (P = 9 × 10⁻⁴). ISOCT markers μ_s and μ_b were not significantly different. By 2P-AF, the redox ratio was 0.24-fold lower in premalignant (0.11 ± 0.004, n = 2) versus benign (0.45 ± 0.04, n = 9) lesions (P = 1.08 × 10⁻⁵).

Conclusions

Conjunctival lesions with higher malignant potential had higher D and lower redox ratios. Higher D can correlate with ultrastructural changes associated with malignancy, similar to what has been seen in cancers of the gut mucosa. Lower redox ratios can suggest the presence of the Warburg effect, which is associated with tumorigenesis.

Translational Relevance

IS-OCT and 2P-AF can potentially be applied to the detection of malignancy or malignant potential in ocular surface lesions. ISOCT allows for the detection of nanoscale ultrastructural changes that are not resolvable by conventional OCT.

Ocular surface squamous neoplasia: angiographic characteristics and response to subconjunctival/perilesional 5-fluorouracil injections

Introduction: To investigate the angiographic characteristics of ocular surface squamous neoplasia (OSSN) and to evaluate the efficacy of subconjunctival/perilesional 5-fluorouracil injections in OSSN cases.

Materials and methods: Six eyes of six patients with primary OSSN, received perilesional, subconjunctival, 25-mg/mL 5-fluorouracil injections at certain intervals. Anterior segment digital photography images, anterior segment optical coherence tomography (AS-OCT), and conjunctival indocyanine green angiography (ICGA) were obtained simultaneously with fluorescein angiography.

Results: The mean best-corrected vision acuity significantly improved after treatment. At baseline, the median of the largest thickness of OSSN was 905.0 (interquartile range: 492.0–1592.5) μm based on AS-OCT data. There was an abrupt transition between normal and abnormal epithelium, a thickened hyper-reflective epithelium, and a sharp plane of cleavage between the lesion and underlying tissue, all indicative of OSSN. The angiographic characteristics of OSSN included focal or seafan-shaped intratumoral and conjunctival feeding vessels visible via ICGA, and abnormal vascular leakage visible with fluorescein angiography. The median time to tumor regression after treatment was 35.0 (interquartile range: 32.0–45.5) days in five eyes without recurrence, and OSSN in one eye regressed partially 40 days after treatment.

Conclusion: This is the first report of the angiographic characteristics of OSSN and its response to subconjunctival/perilesional 5-fluorouracil injections by simultaneous conjunctival angiography and AS-OCT. The improved subconjunctival/perilesional 5-fluorouracil injection was an effective therapy for OSSN in both best-corrected vision acuity gain and anatomic outcomes.

Resolution of giant ocular surface squamous neoplasia with topical 5-fuorouracil 1

An 82-year-old man presented with a left eye elevated single ocular surface squamous neoplasia. The tumor involved 360° of limbus, three quadrants of cornea and conjunctiva; this was compatible with the diagnosis of giant ocular surface squamous neoplasia. Topical 5-fluorouracil 1% was planned four times daily for 1 week followed by 3 weeks off-treatment. Patient inadvertently continued 5-fluorouracil, four times daily for 4 weeks, presenting with clinical resolution of the ocular surface squamous neoplasia and subtotal corneal epithelial defect associated with 5-fluorouracil toxicity. One month later, we observed a transparent cornea and no signs of toxicity. Total tumor resolution was observed for at least 6 months of follow-up.

Extending far and wide: the role of biopsy and staging in the management of ocular surface squamous neoplasia

IMPORTANCE

Although the most recent American Joint Committee on cancer staging guidelines for ocular surface squamous neoplasia place a heightened emphasis on biopsy and histopathologic analysis, the interpretation and clinical relevance of these staging criteria are not always clear. We address limitations of using histopathologic analysis to predict clinical outcomes and suggest less-invasive assessments.

BACKGROUND

To investigate the impact of histopathologic depth of invasion on outcomes for tumours with the common presentation of multiple structure involvement.

DESIGN

Retrospective chart review at tertiary institution.

SAMPLES

Of 41 eyes with ocular surface squamous neoplasia between 2012 and 2017, 27 tumours involving multiple ocular structures clinically were included.

METHODS

Biopsied tumours were determined to be invasive beyond the basement membrane or non-invasive; non-biopsied tumours were clinically identified with unknown depth of invasion. Outcomes were compared using Fisher's exact or Student's t tests.

MAIN OUTCOME MEASURES

Proportion of tumours cured, recurred and/or persisting.

RESULTS

Twelve tumours (44%) received primary excisional biopsy, 10 (37%) received chemotherapy without biopsy and 5 (19%) received chemotherapy and biopsy. Clinical diagnosis was correct in all biopsied cases. While there were no significant differences in outcomes between invasive vs non-invasive tumours or treatments, there was a trend toward larger basal diameter in recurrent tumours regardless of treatment.

CONCLUSIONS AND RELEVANCE

When ocular surface squamous neoplasia tumours with similar clinical involvement were compared, histopathologic depth of invasion was not predictive of clinical outcomes. Future staging criteria may consider the potential of largest basal dimension for more accurate prognostication.

Anterior segment optical coherence tomography: its application in clinical practice and experimental models of disease

Optical coherence tomography (OCT) provides non-invasive, high-resolution in vivo imaging of the ocular surface and anterior segment. Over the years, it has become an essential tool for evaluating the anterior segment of the eye to monitor ocular development and ocular pathologies in both the clinical and research fields of ophthalmology and optometry. In this review, the clinical applications relating to the use of anterior segment OCT for imaging and quantifying normal and pathological features of the ocular surface, cornea, anterior chamber, and aqueous outflow system are summarised in a range of human ocular diseases. Applications of anterior segment OCT technology that have improved imaging and quantitation of ocular inflammation in experimental animal models of ocular diseases, such as anterior uveitis, microbial keratitis and glaucoma, are also described. The capacity to longitudinally evaluate anterior segment anatomical changes during development, and inflammation facilitates the understanding of the dynamics of tissue responses, and further enhances the intra-operative in vivo imaging during procedures, such as corneal transplantation and drug delivery. Future developments including in vivo ultrahigh-resolution anterior segment OCT, automated analyses of anterior segment OCT images and functional extensions of the technique, may revolutionise the clinical evaluation of anterior segment, corneal and ocular surface diseases.

Ability of novice clinicians to interpret high-resolution optical coherence tomography for ocular surface lesions

OBJECTIVE

To assess the ability of novice clinicians to use a commercially available high-resolution anterior segment optical coherence tomography (HR-OCT) device to diagnose various lesions of the ocular surface and cornea.

METHODS

Cross-sectional study. Twenty-six black-and-white HR-OCT images were projected, and clinicians were asked to determine whether the lesions represented ocular surface squamous neoplasia (OSSN) or another ocular surface pathology. A 20-minute instructional lecture was given on HR-OCT interpretation, and the same 26 images were shown. The clinicians were asked to repeat their assessment of the lesions. Thirty-four novice clinicians at the Bascom Palmer Eye Institute, Miami, FL, participated. A commercially available device (RTVue, Optovue, Fremont, Calif.) was specifically chosen for this study.

RESULTS

The mean frequency of correct identification of the 26 lesions was 70% (standard deviation [SD] 15%) before instruction; after a short lecture, the frequency of correct identification improved to 84% (SD 9%, p = 0.002). Novice clinicians were more accurate in correctly determining that a lesion was not an OSSN (ruling it out as a diagnosis) than in determining that a lesion was an OSSN (p = 0.001). Some lesions (both OSSN and not OSSN), however, were more difficult to interpret than others.

CONCLUSION

This study demonstrated that all levels of novice clinicians can quickly improve diagnostic accuracy with a commercially available HR-OCT after a short training session.

Topical interferon alpha-2B topic as the first therapeutic option in a clinical case of conjunctival intraepithelial neoplasia

INTRODUCTION

Conjunctival intraepithelial neoplasia is a pre-malignant lesion of the ocular surface. It can be treated with topical interferon alpha-2b (INF α-2b) as first choice.

CLINICAL CASE

A 71-year-old man referred for corneal-conjunctival, gelatinous lesion in the left eye (LE) with an area of almost 270°. The clinical diagnosis was compatible with a corneal-conjunctival intraepithelial neoplasia. Topical treatment was started with INF α-2b at a dose of one million international units (IU)/ml, 4 times/day for 4 months, with remission being achieved.

CONCLUSION

The isolated use of topical INF α-2b is an effective treatment as a first option in the case of corneal-conjunctival intraepithelial neoplasia, positioning itself as a form of effective and safe treatment compared to other therapeutic options. Surgical excision and use of other chemotherapy agents could lead to severe limbic deficits and other side effects.

Role of high resolution optical coherence tomography in diagnosing ocular surface squamous neoplasia with coexisting ocular surface diseases

PURPOSE

Coexistence of an ocular surface disease can mask the typical features of ocular surface squamous neoplasia (OSSN). The purpose of this study was to evaluate high resolution optical coherence tomography (HR-OCT) as an adjunct in the detection and differentiation of OSSN within coexisting ocular surface pathologies.

METHODS

Retrospective study of 16 patients with ocular surface disease and lesions suspicious for OSSN that were evaluated with HR-OCT. HR-OCT images of the lesions were taken to look for evidence of OSSN. Biopsies were performed in all cases, and the HR-OCT findings were compared to the histological results.

RESULTS

Of the 16 patients with OSSN and a coexisting ocular surface disease, 12 were found to have OSSN by HR-OCT and all were subsequently confirmed by biopsy. Two patients had OSSN with rosacea, one with pingueculum, two within pterygia, one with Salzmann' nodular degeneration, six with limbal stem cell deficiency (LSCD)/scarring. In all 12 cases HR-OCT images revealed classical findings of hyper-reflective, thickened epithelium and an abrupt transition from normal to abnormal epithelium. OSSN was ruled out by HR-OCT in four cases (2 Salzmann's, 1 mucous membrane pemphigoid, and 1 LSCD). Negative findings were confirmed by biopsy. HR-OCT was used to follow resolution of the OSSN in positive cases, and it detected recurrence in 1 case.

CONCLUSIONS

While histopathology is the gold standard in the diagnosis of OSSN, HR-OCT can be used to noninvasively detect the presence of OSSN in patients with coexisting ocular conditions.