Publications by authors named "Rob J W De Keizer"

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.

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Background/objectives: To evaluate the management of conjunctival melanoma with local excision and adjuvant brachytherapy.

Subjects/methods: Data of all patients who received local excision and adjuvant brachytherapy for conjunctival melanoma between 1999 and 2016 in a Dutch national referral centre were reviewed. A protocol with Sr-90 was used until 2012, a protocol with Ru-106 was used hereafter.

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. To analyze and describe corneal and conjunctival tumor thickness and internal characteristics and extension in depth and size and shape measured by two noninvasive techniques, anterior segment optical coherence tomography (AS-OCT) and ultrasound biomicroscopy (UBM). .

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Uveal melanomas (UM) originate from melanocytes in the interior wall of the eye, namely from the iris, ciliary body and the choroid with marked differences in light exposure (from dark anterior to illuminated posterior). In contrast to UV radiation, focused or converging visible light readily reaches the retina and can damage DNA which possibly contributes to UM development. In this report choroidal, ciliochoroidal and iridociliary melanomas were analyzed for GNAQ and GNA11 mutations which were subsequently correlated to the location of tumor origin.

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We describe the intraocular lens (IOL) exchange technique that is specific to the bag-in-the-lens IOL. The subsequent IOL analysis displayed a deep granular opacification consisting predominantly of calcium and phosphates that has been described in hydrophilic IOLs.

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Purpose: To evaluate the clinical and histopathological characteristics of silent skin squamous cell carcinomas (SCC) with invasion routes to the orbit.

Methods: Retrospective case studies. Clinical records and histopathological material, therapy and complications were evaluated, together with MRI imaging analyses and literature review on the anatomy of the lateral orbital wall in relation to the zygomatico-temporal nerve channel.

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Objective: To collaborate with multiple centers to identify representative epidemiological, clinical, and pathologic characteristics of melanoma of the iris. This international, multicenter, Internet-assisted study in ophthalmic oncology demonstrates the collaboration among eye cancer specialists to stage and describe the clinical and pathologic characteristics of biopsy-proven melanoma of the iris.

Methods: A computer program was created to allow for Internet-assisted multicenter, privacy-protected, online data entry.

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Purpose: To determine the role of anterior segment optical coherence tomography (AS-OCT) and other anterior segment imaging techniques (Pentacam, slit-lamp optical coherence tomography [SL-OCT]) for analysis of iris melanocytic tumors and to compare results with clinical features and ultrasound biomicroscopy (UBM).

Methods: Between 2006 and 2009, 61 patients with melanocytic iris tumors were examined using different anterior segment imaging techniques: Pentacam, SL-OCT, AS-OCT, and UBM (50 MHz). Pentacam was performed in 17 patients, SL-OCT in 12, AS-OCT in 46, and UBM in 49.

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Purpose: To determine the long-term effects of ruthenium-106 plaque radiation therapy for iris and iridociliary melanomas in terms of tumour regression and complications.

Methods: Between 1 November 1997 and 31 December 2007, 36 patients with an iris or iridociliary melanoma were treated with Ruthenium-106 (Ru-106) ophthalmic plaque radiation therapy. The median follow-up was 6.

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Purpose: Pigmented lesions of the conjunctiva are often difficult to classify clinically. Exfoliative cytology may be helpful, but reliable data regarding the sensitivity and specificity of this test are currently lacking. We determined the value of exfoliative cytology with regard to pigmented conjunctival lesions.

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Ags expressed at immune privileged sites and other peripheral tissues are able to induce T cell tolerance. In this study, we analyzed whether tolerance toward an intraocular tumor expressing a highly immunogenic CTL epitope is maintained, broken, or reverted into immunity in the event the anatomical integrity of the eye is lost. Inoculation of tumor cells into the anterior chamber of the eye of naive B6 mice leads to progressive intraocular tumor growth, an abortive form of CTL activation in the tumor-draining submandibular lymph node, and systemic tolerance as evidenced by the inability of these mice to reject an otherwise benign tumor cell inoculum.

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Purpose: To evaluate risk factors for local recurrence, regional and distant metastases, and mortality associated with conjunctival melanoma.

Methods: This was a retrospective study of 194 patients with histologically confirmed conjunctival melanoma diagnosed between 1950 and 2002 in the Netherlands. Data were collected from all university centers and many nontertiary hospitals, using the National Pathology and the Leiden Oncologic Registration Systems.

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