Identification of Feeder Vessels in Ocular Surface Neoplasia Using Indocyanine Green Angiography.

PURPOSE: To evaluate indocyanine green angiography (ICGA) for the identification and characterization of afferent (feeding) and efferent (draining) vessels in patients with ocular surface neoplasia. MATERIALS AND METHODS: Consecutive patients with biopsy-proven benign, pre-invasive, or invasive ocular surface tumors of the bulbar conjunctiva were included. Patients underwent anterior segment optical coherence tomography, ICGA, and color photography for the evaluation of the thickness, location, number, and diameter of afferent and efferent vessels of the lesions. RESULTS: Twenty-two eyes of 22 patients with papillomas (n = 4), intra-epithelial neoplasia lesion (n = 2) in situ or invasive carcinomas (n = 6), nevus (n = 5), conjunctival melanocytic intra-epithelial neoplasia lesion (n = 1), and in situ or invasive melanomas (n = 4) were investigated. Afferent (feeder) vessels were identified in all lesions. There were fewer afferent (3.1 ± 1.6) than efferent (7.5 ± 3.5) vessels per lesion (p < 0.001) and the mean diameter was smaller for afferent (101 ± 62 µm, 28-281) than efferent vessels (137 ± 51 µm, 31-652; p = 0.017). The number of afferent and efferent vessels was associated with the thickness of the lesion (p = 0.037, p < 0.01). Lesion filling times differed between benign and invasive or pre-invasive lesions (p = 0.018). CONCLUSIONS: ICGA is a useful adjunctive in vivo imaging method for the assessment of the vasculature in patients with suspected ocular surface neoplasia.

Usefulness of colour Doppler flow imaging in the management of lacrimal gland lesions.

OBJECTIVE: To assess the role of colour Doppler flow imaging (CDFI) in the diagnosis and management of lacrimal fossa lesions. METHODS: Institutional ethical committee approval was obtained. Fifty-one patients with 62 lacrimal fossa lesions were retrospectively included from 2003-2015. All patients underwent conventional ultrasonography and CDFI, with a qualitative and quantitative analysis of the vascularization. All patients had lacrimal gland surgery. Definitive diagnosis was based on pathological examination. RESULTS: The study included 47 non-epithelial lesions (NEL) and 15 epithelial lesions (EL), with 24 (39 %) malignant lesions and 38 (61 %) benign lesions. NEL were significantly more likely to present with septa (p < 0.001), hypoechogenicity (p < 0.001), high vascular intensity (p < 0.001), both central and peripheral vascularization (p < 0.001), tree-shape vascularization (p < 0.05) and a low resistance index (RI) (p < 0.0001). EL were significantly more likely to present with the presence of cysts (p < 0.001), and a higher RI. Receiver operating characteristic curves identified a RI value of 0.72 as the best cut-off to differentiate NEL from EL, with a sensitivity and specificity of 100 %. CONCLUSION: CDFI is a valuable tool in the differential diagnosis of lacrimal fossa lesions. Resistance index measurement enables substantial distinction between EL and NEL, thus providing crucial data for surgical management. KEY POINTS: • CDFI is a valuable tool in lacrimal fossa lesions. • Resistance Index measurement enables substantial distinction between epithelial and non-epithelial lesions. • Management of patients becomes more appropriate.

[Influence of nerve growth factor (NGF) on distribution of perivascular nerves in tumor neovasculatures of mouse corneal].

Angiogenesis, or new blood vessel formation, is critical for the growth and spread of tumors. The vascular tone and tissue blood flow are maintained and regulated by perivascular nerves. However, many studies have reported that tumor neovascular vessels have no innervation of perivascular nerves. We have shown that nerve growth factor (NGF) facilitated perivascular innervation and suppressed the tumor growth. From these results, we hypothesized that the neuronal regulation of blood flow toward tumors via perivascular nerves may lead suppression of the tumor growth. Therefore, the aim of this study is to investigate effect of NGF on distribution of perivascular nerves and neovessel form in tumor tissues, which were generated by mouse corneal micropocket method. A gel, which contained DU145 prostate carcinoma cells, was implanted into the mouse corneal. NGF or saline was subcutaneously administered using an osmotic mini-pump. After 1 week, the distribution of perivascular nerves in mouse corneal were immunohistochemically studied. Also, the density of neovessels (immunocytochemically stained CD31) and smooth muscles (α-smooth muscle actin; SMA) in tumor tissues was quantified by the computer-assisted image processing. Four days after implantation of tumor cells in mouse corneal, many neovessels generated from corneal limbal vessels were observed in tumor tissues. Treatment of mouse with NGF resulted in innervation of perivascular nerves around tumor neovessels, but not observed in saline-treated group. NGF treatment increased SMA-, but not CD31-, immunopositive cells. These results suggest that NGF may facilitate innervations of perivascular nerve to regulate the blood flow in tumor neovessels.

Intraocular biopsy using special forceps: a new instrument and refined surgical technique.

AIM: The aim was to investigate the Essen biopsy forceps as a new instrument and surgical approach for biopsy of intraocular tumours. Biopsy is indicated for assessment of any uncertain intraocular process or confirmation for presumed diagnosis before treatment. There is increasing interest for further genetic and immunocytological information in order to characterise the neoplasm, especially grading and prognosis of micrometastasis in uveal melanoma. The authors have developed a new surgical technique using special intraocular biopsy forceps. METHODS: Twenty patients with uncertain intraocular subretinal tumour underwent biopsies carried out using the special Essen biopsy forceps. Biopsies were obtained through sutureless 23-gauge three-port vitrectomy. A small retinotomy tumour specimen was taken by the forceps branches. For further processing, the specimens were flushed out into a sterile tube and then sent to pathologists. RESULTS: The prebioptical tumour had a mean thickness of 3.48 mm (1.1 to 9.8 mm). In all cases (n=20) biopsies (0.3-2.1 mm in size) were obtained, in 19 cases (95%) allowing precise histological and immunohistochemical typing of the lesions following cytoblock embedding. Uveal melanoma was diagnosed in 50% (n=10), choroidal metastasis in 15% (n=3) and choroidal naevus in 15% (n=3); other diagnoses (n=3) included choroidal haemangioma, B cell lymphoma and old subretinal haemorrhage. Apart from three patients with temporary punctual bleeding on the surface, there were no intra- and postoperative complications. CONCLUSIONS: Biopsy using special forceps is a promising new approach and precise surgical procedure. Especially for small intraocular tumours, this technique has the advantage in providing enough tissue for improved histological examination and presenting a low risk for complications.

Hematolymphoid malignancies with intraocular intravascular involvement: report of 2 cases.

The interaction between the endothelium and malignant hematolymphoid cells within vessels of the eye can result in focal or diffuse intravascular pathology. As a result, correlation of these findings with specific clinical and ophthalmologic features can vary. We review the ophthalmic findings in two cases of hematolymphoid malignancies limited to the intravascular space and review published literature on this topic. In cases of intravascular large B-cell lymphoma, underexpression of ß1-integrin and intercellular adhesion molecule-1 by the cells of intravascular large B-cell lymphoma results in diffuse ocular vascular involvement. The widespread degree of intravascular involvement correlates with clinical ophthalmologic findings and may lead to retinal and choroidal detachment that is observed postmortem. Conversely, in the context of acute leukemia, induced overexpression of certain adhesion molecules (intercellular adhesion molecule-1 and vascular cell adhesion molecule-1) in the endothelium of certain vascular beds may result in leukostasis with only selective (choroidal) ocular vessel involvement. As a result of only focal vascular activation and adhesion in the orbit, the gross findings in these cases are minimal and may not correlate with clinical ophthalmologic findings.

In aged mice, outgrowth of intraocular melanoma depends on proangiogenic M2-type macrophages.

Macrophages are part of the tumor microenvironment and have been associated with poor prognosis in uveal melanoma. We determined the presence of macrophages and their differentiation status in a murine intraocular melanoma model. Inoculation of B16F10 cells into the anterior chamber of the eye resulted in rapid tumor outgrowth. Strikingly, in aged mice, tumor progression depended on the presence of macrophages, as local depletion of these cells prevented tumor outgrowth, indicating that macrophages in old mice had a strong tumor-promoting role. Immunohistochemistry and gene expression analysis revealed that macrophages carried M2-type characteristics, as shown by CD163 and peroxisome proliferator-activated receptor gamma expression, and that multiple angiogenic genes were heavily overrepresented in tumors of old mice. The M2-type macrophages were also shown to have immunosuppressive features. We conclude that tumor-associated macrophages are directly involved in tumor outgrowth of intraocular melanoma and that macrophages in aged mice have a predisposition for an M2-type profile.

Contrast-enhancement of the anterior eye segment in patients with retinoblastoma: correlation between clinical, MR imaging, and histopathologic findings.

BACKGROUND AND PURPOSE: AES contrast-enhancement is recognized in a substantial number of retinoblastoma-affected eyes. We retrospectively investigated the histopathologic basis of AES contrast-enhancement on MR images in retinoblastoma. MATERIALS AND METHODS: Pretreatment contrast-enhanced MR images were obtained from 42 children with retinoblastoma. Forty-two enucleated eyes were included in this study, AES enhancement was evaluated by using a 3-point score, and these data were correlated with clinical, MR imaging, and histopathologic findings. Additionally, 14 specimens were immunohistochemically analyzed for CD31, VEGF, and Flt-1 expression. Statistical correlations with AES enhancement were assessed by using a linear-by-linear association test and univariate and multivariate ordinal regressions. RESULTS: The degree of abnormal AES enhancement was moderate in 15 (36%) eyes and strong in 14 (33%) eyes, whereas 13 (31%) eyes showed normal AES enhancement. In multivariate analysis, the degree of AES enhancement showed statistically significant correlations with iris surface-vessel count (P = .05) and optic nerve invasion (P = .04) in the enucleated eye and with tumor volume (P = .02) as detected on MR imaging. No significant associations between AES enhancement and VEGF expression in the iris were observed. Flt-1 (P = .04) staining in iris stroma and IA as detected with CD31 staining (P = .009) both yielded a statistically significant positive correlation with abnormal AES enhancement. CONCLUSIONS: The degree of abnormal AES enhancement on MR imaging in retinoblastoma reflects angiogenesis in the iris. AES enhancement is also a hallmark of advanced retinoblastoma because its degree correlates with tumor volume and optic nerve invasion.

[Angiogenesis and antiangiogenesis in intraocular tumors]. / Angiogeneza si antiangiogeneza în tumorile intraoculare.

Angiogenesis, fundamental process that consists in the formation of new vessels, is essential physiologically in the tissue maintenance and of the homeostasis, having in this sense a few positive and negative regulators. Vascular endothelial growth factor and other angiogenical proteins play a major role in the ocular and general angiogenesis. The solid tumors need new vessels in order to survive and grow, therefore the anti-angiogenic agents can represent important instruments in the ocular oncological therapy The intravitreal administration of the anti-VEGF agents delay the growth of the intraocular tumors, decreases the odds of their methastasis at distance, increases the therapeutical effects of the conservative treatment by irradiation and can limit the ocular complications of radiotherapy.

Current molecular understanding and future treatment strategies for pathologic ocular neovascularization.

The leading cause of blindness in the developed world results from several disorders that have pathologic ocular neovascularization as the common pathway leading to vision loss. These disorders include exudative age related macular degeneration (AMD), diabetic retinopathy (DR), retinopathy of prematurity (ROP), retinal vein occlusions (RVO) and ocular tumors. Because neovascularization is the common pathway to blindness in these highly prevalent conditions, the recent understanding of the cascade of angiogenesis has led to clinically available molecular therapeutics that have been proven to restore and preserve vision in patients that suffer from these blinding conditions. This article will summarize the emergence of vascular endothelial growth factor (VEGF) as a validated treatment target for and current understanding of the pathophysiology of ocular neovascularization. The article will then cover promising future strategies and therapeutic targets that are aimed at enhancing the efficacy and/or duration of effect of these clinically available anti-VEGF strategies. In particular molecules that target, VEGF, PDGF, Complement, Inflammation and Integrins that are entering or are currently in clinical trials will be reviewed.

A boundary element model for investigating the effects of eye tumor on the temperature distribution inside the human eye.

A three-dimensional boundary element model of the human eye is developed to investigate the thermal effects of eye tumor on the ocular temperature distribution. The human eye is modeled as comprising several regions which have different thermal properties. The tumor is one of these regions. The thermal effects of the tumor are simulated by taking it to have a very high metabolic heat generation and blood perfusion rate. Inside the tumor, the steady state temperature is governed by the Pennes bioheat equation. Elsewhere, in normal tissues of the eye, the temperature satisfies the Laplace's equation. To compute the temperature on the corneal surface, the surface boundary of each region is divided into triangular elements.