Shahar Frenkel

The Learning Effect in Visual Field Testing of Healthy Subjects Using Frequency Doubling Technology

PurposeTo evaluate the presence, duration and magnitude of a learning effect in serial visual field (VF) testing, using the commercially available frequency doubling technology (FDT) instrument. Patients and Methods21 healthy adults with no prior VF experience underwent 6 serial VF tests, using the full-threshold C-20 program of the Zeiss-Humphrey FDT analyzer, on one randomly chosen eye. Tests were spaced at least two days apart. ResultsThe average mean sensitivity was 32.37 ± 2.6 dB; the average mean deviation (MD) was 1.22 ± 1.8 dB. The MD at the first examination (0.28 ± 2.1 dB) was significantly poorer than at any of the other testing sessions (p<0.003). Similarly, the mean sensitivity at the first examination (31.16 ± 3.0 dB) was significantly lower than any other testing session (p<0.004). The proportion of improvement from the first to the second session was 63% and 65% of the total improvement, for mean sensitivity and MD, respectively. Mean test duration showed a modest reduction, from 4.40 ± 0.3 minutes in the first session to 4.17 ± 0.4 minutes in the last session (p = 0.023). A sub-analysis comparison of the different VF segments showed a more prominent learning effect in the peripheral and nasal visual segments (p<0.0001). ConclusionBaseline measurements should best rely on the second testing session, since MD and mean sensitivity are somewhat poorer when subjects with no prior VF experience are first tested on the FDT instrument. This may be especially true for the purpose of following patients over time.

Punch biopsy of iris lesions: a novel technique for obtaining histology samples

Aim: To obtain iris biopsy samples of sufficient quality and quantity for histopathological analysis using a novel punch biopsy technique. Methods: Two patients underwent iris tumour biopsy at an ocular oncology service. A trabeculectomy punch (Kelly Descemet’s membrane punch) with a 1.0 mm diameter head and a 0.75 mm deep bite was inserted through a clear cornea perforated by a SatinSlit 3.2 mm angled slit knife into a viscoelastic-filled anterior chamber. The Kelly punch was placed over the lesion and pressed down before the punch was made. After obtaining the sample, the Kelly punch was removed from the eye and then opened over a dry cellulose sponge. Tissue samples were placed in 4% formalin and processed routinely for standard staining with H&E, periodic acid Schiff and immunostains. Results: In both patients, by using the punch biopsy technique with the Kelly punch, we were able to obtain a 0.8×0.6 mm piece of tissue, large enough for any histological analysis. H&E staining showed spindle cell melanoma. Tissue sections, stained positive with MART-1 (melanoma antigen recognised by T cells) and negative with cytokeratin, established the diagnosis of melanoma of the iris in each of these patients. Conclusions: Iris biopsy with the punch technique yields a tissue biopsy specimen, as opposed to cytology samples obtained by fine needle aspiration biopsy. This technique is quick, simple to perform and requires non-expensive and easily available equipment. The tissue obtained is of sufficient quality and quantity to enable routine and special stainings.

Prevalence of clinical asymptomatic retinal detachment in myopic population

Aim: To evaluate the prevalence of clinical asymptomatic retinal detachment (ARD) in myopic population. Methods: A retrospective study including all myopic individuals who underwent ophthalmic evaluation prior to excimer laser procedures at the Hadassah Center for Refractive Surgery between March 2002 and March 2006. Medical records were reviewed to extract demographics and refraction, and to identify patients who were diagnosed as having asymptomatic retinal detachment. Results: Data were collected on 6547 myopic individuals (12 815 eyes); of these, 2907 (44.4%) were males, and 3640 (55.6%) were females. The mean age was 31.5 (SD 10) years (range 18–64 years). The mean preoperative spheric equivalence was −4.42 (2.07) (range −0.75 to −16.00). The mean best spectacle-corrected visual acuity was 20/20 (range 20/32 to 20/12.5). Five eyes (0.039% or one of approximately 2563 eyes) of four patients had clinical ARD which was diagnosed during the routine preoperative examination. Three eyes underwent successful scleral buckling procedure while two patients were lost to follow-up. Conclusions: Clinical asymptomatic retinal detachment is uncommon, accounting for a minority of retinal detachments in myopes, and may be diagnosed during routine ophthalmoscopy prior to a refractive procedure.

Sector iridectomy of iris melanoma: a novel technique for excising the melanoma extraocularly

Iris melanomas constitute between 3% and 10% of all malignant melanomas of the uvea and, unlike posterior uveal melanoma, have a low rate of metastasis.1 The most common way of treating circumscribed iris melanoma is by partial, usually sector, iridectomy,2 with iris reconstruction where possible. When the anterior chamber angle or ciliary body is involved, iridotrabeculectomy or iridocyclectomy should be performed. Complications of iridectomy include hyphema, cataract, wound dehiscence, episcleral seeding of the tumour and vitreous loss.1 Non-resectable iris melanoma can be treated by brachytherapy using radioactive plaque3 or proton beam irradiation.4 Diffuse iris melanoma, which often involves the trabecular meshwork and causes secondary glaucoma, is usually treated by enucleation.5 We describe herein a novel technique of sector iridectomy in treating circumscribed iris melanoma. The operation is performed by pushing the tumour out of the eyeball and excising it extraocularly, without intraocular intervention, in order to prevent anterior segment complications. Six patients with growing pigmented iris lesions suspicious for iris melanoma, three of them proven histologically by punch biopsy, underwent resection using this new technique at the Hadassah-Hebrew University Medical Center between 2002 and 2007. All patients signed an informed consent for the described surgery. All …

Risk of extraocular extension in eyes with retinoblastoma receiving intravitreous chemotherapy

Importance The risk of extraocular extension from injecting chemotherapy into eyes with retinoblastoma is minimally understood; however, understanding this risk is important because of the increasing use of intravitreous chemotherapy. Objective To evaluate the risk of extraocular extension in eyes with retinoblastoma that have received intravitreous chemotherapy injections. Design, Setting, and Participants This retrospective cohort study was performed in 655 patients at 10 retinoblastoma centers in North and South American, European, Israeli, and Chinese centers. Physicians at the retinoblastoma centers administered more than 120 intravitreous chemotherapy injections in eyes with retinoblastoma from February 1, 1999, through February 28, 2017. Main Outcomes and Measures Risk of extraocular extension with secondary observational variables, including injection and precautionary techniques. Results A total of 3553 intravitreous chemotherapy injections (3201 melphalan hydrochloride, 335 topotecan hydrochloride, and 17 methotrexate sodium) were administered to 704 eyes in 655 patients with retinoblastoma (mean [SD] age of patients at the time of the initial injections, 31.6 [11.6] months; 348 male [53.1%]). There were no extraocular tumor events related to prior intravitreous injections. This finding resulted in a calculated proportion of zero extraocular events per eye. According to the rule of 3, the risk is no greater than 0.08% injections. All 10 centers included in this study used at least 2 presumed precautionary injection methods (lowering of intraocular pressure, cryotherapy, ocular surface irrigation, ultrasonic biomicroscopy surveillance of the injection site, and subconjunctival chemotherapy deposition). Conclusions and Relevance With use of at least 2 presumed precautionary safety methods, no extraocular extension of tumor events occurred. According to the rule of 3, this finding suggests that the risk is no greater than 0.08% injections.

Choroidal metastasis of adenocarcinoma of the lung presenting as pigmented choroidal tumor.

Our case represents a unique occurrence of pigmented choroidal tumor that clinically appeared as choroidal melanoma and was treated accordingly. At the same time, while evaluating the patient for systemic metastases of uveal melanoma, she was diagnosed as having lung carcinoma. Events that led to the enucleation of the eye enabled a histological diagnosis: pulmonary adenocarcinoma. In our case, it happened that a very rare pigmented choroidal metastatic tumor was the presenting sign of a pulmonary adenocarcinoma.

A novel combinatorial treatment option for metastatic uveal melanoma

Uveal melanoma (UM) is the most frequent intraocular tumor in adult patients. When metastases occur, systemic therapy with alkylating agents (fotemustine or dacarbazine (DTIC)) has shown only modest efficacy. The common chemotherapeutic drug doxorubicin (DOX) is not used to treat metastatic UM (mUM). To expand the chemotherapeutic arsenal for mUM, we tested the effect of DOX on UM cell mortality. We have previously shown that CREB knockdown enhances sensitivity to DOX. UM cells infected with recombinant MuLV-based replicative competent retroviruses (RCR) expressing shRNA targeting CREB were co-treated with either DTIC or DOX. We found that CREB knockdown increases the sensitivity of these cells to both DOX and DTIC in normoxia and more so in hypoxia as measured by cell survival and Caspase 3 activation. The ability to combine CREB knockdown by infection with the RCR recombinant virus which preferentially infects replicating tumor cells and chemotherapy to achieve the same amount of cell death in lower concentrations may result in fewer side effects of the drugs. This combination is a possible new treatment for mUM.

Assessing visual function behind cataract: preoperative predictive value of the Heine Lambda 100 retinometer

Purpose To analyze the accuracy of the Lambda 100 (Heine) potential visual acuity (VA) measurements in subjects undergoing cataract surgery. Methods The medical records of all consecutive patients who underwent clear corneal incision phacoemulsification cataract surgery by a single surgeon between 2010 and 2012 at the Department of Ophthalmology, Hadassah Medical Center, a tertiary care hospital in Jerusalem, Israel, were reviewed. Subjects age 18 or older with a follow-up time of at least 30 days were included. Subjects with previous ocular comorbidities other than glaucoma were excluded. In addition, patients with intraoperative or perioperative complications that could affect final VA were excluded. Analyses were performed to analyze the accuracy of preoperative retinometer potential VA as a predictor of postoperative best-corrected VA. Results A total of 374 operated eyes were included. There was a moderate positive correlation between Lambda estimated VA potential and postoperative achieved best-corrected VA (BCVA) (β coefficient 0.35, p<0.0001). Overall Lambda accurately (within 2 Snellen lines) estimated postoperative BCVA results in 60% of cases. The accuracy of prediction was significantly better in moderate cataracts when compared with advanced cataracts (p<0.01) with a twofold tendency towards underestimation in advanced cataracts. A Lambda ≥0.5 decimal has a calculated positive predictive value of 82% and a negative predictive value of 40% for predicting postoperative BCVA outcome ≥0.5 decimal. Conclusions Lambda may be used to relatively accurately predict postoperative BCVA in cataract patients, specifically in those with moderate cataracts.

The Role ofRASSF1Ain Uveal Melanoma

PURPOSE RASSF1A inactivation in uveal melanoma (UM) is common and methylation-induced. We investigated the effect of RASSF1A re-expression on the UM phenotype in vivo and in vitro. METHODS The phenotypic effect of methylation-induced inactivation of RASSF1A in UM was explored using a stable RASSF1A-expressing UM-15 clone. RASSF1A expression was assessed using QRT-PCR. Proliferation was evaluated in vitro using MTT assays. Additionally, athymic NOD/SCID mice were injected subcutaneously or intraocularly with RASSF1A-expressing and -non-expressing UM-15 clones, and euthanized when tumors reached a volume of 1500 mm(3), or at 56 or 46 days, respectively. Tumor tissues, eyes, and livers were analyzed histologically. RESULTS In vitro analysis confirmed the lack of RASSF1A expression and full methylation of the RASSF1A promoter region in the UM-15 cell line, which was reversible following treatment with 5-Aza-2-deoxycytidine. Cells expressing exogenous RASSF1A showed slower proliferation than controls and regained sensitivity to cisplatin. Compared to mice injected with control cells, mice treated with UM-15 cells expressing exogenous RASSF1A did not acquire intraocular tumors, and their subcutaneous tumors were relatively delayed and small. Neither group had liver metastases. CONCLUSIONS UM cells reduced tumorigenicity in the presence of activated RASSF1A. RASSF1A apparently has an important role in the development of UM, and its reactivation might be applied in the development of new treatments.

The Role of RASSF1A in Uveal Melanoma RASSF1A in Uveal Melanoma

PURPOSE RASSF1A inactivation in uveal melanoma (UM) is common and methylation-induced. We investigated the effect of RASSF1A re-expression on the UM phenotype in vivo and in vitro. METHODS The phenotypic effect of methylation-induced inactivation of RASSF1A in UM was explored using a stable RASSF1A-expressing UM-15 clone. RASSF1A expression was assessed using QRT-PCR. Proliferation was evaluated in vitro using MTT assays. Additionally, athymic NOD/SCID mice were injected subcutaneously or intraocularly with RASSF1A-expressing and -non-expressing UM-15 clones, and euthanized when tumors reached a volume of 1500 mm(3), or at 56 or 46 days, respectively. Tumor tissues, eyes, and livers were analyzed histologically. RESULTS In vitro analysis confirmed the lack of RASSF1A expression and full methylation of the RASSF1A promoter region in the UM-15 cell line, which was reversible following treatment with 5-Aza-2-deoxycytidine. Cells expressing exogenous RASSF1A showed slower proliferation than controls and regained sensitivity to cisplatin. Compared to mice injected with control cells, mice treated with UM-15 cells expressing exogenous RASSF1A did not acquire intraocular tumors, and their subcutaneous tumors were relatively delayed and small. Neither group had liver metastases. CONCLUSIONS UM cells reduced tumorigenicity in the presence of activated RASSF1A. RASSF1A apparently has an important role in the development of UM, and its reactivation might be applied in the development of new treatments.