8 research outputs found

    Investigation into the quantitative and qualitative characteristics of choroidal melanoma through magnetic resonance imaging and B-scan ultrasound

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    Vassilis Papayiannis,1 Konstantinos T Tsaousis,2,3 Constantinos A Kouskouras,4 Afroditi Haritanti,4 Vasilios F Diakonis,5 Ioannis T Tsinopoulos2 1Department of Radiology, Papageorgiou General Hospital, 2Department of Ophthalmology, Aristotle University of Thessaloniki, Thessaloniki, Greece; 3John A Moran Eye Center, University of Utah, Salt Lake City, UT, USA; 4Department of Radiology, AHEPA Aristotle University Hospital of Thessaloniki, Thessaloniki, Greece; 5Bascom Palmer Eye Institute, Miller School of Medicine, University of Miami, Miami, FL, USA Objective: To investigate the homogeneity and vascularity of choroidal melanoma through magnetic resonance imaging (MRI) and brightness modulation (B-mode) ultrasound scan and their correlation with dimensions of tumor, as well as to measure the sensitivity of both modalities in retinal detachment (RD) detection.Materials and methods: This retrospective chart review included patients diagnosed with choroidal melanoma. All these patients underwent MRI scans using T2-weighted (T2-WI) and T1-weighted (T1-WI) sequences, before and after an intravenous injection of paramagnetic contrast material. The patients were also examined using a B-mode ultrasound scan, and the results from both modalities were compared (tumor homogeneity, tumor height, tumor base diameter, and tumor vascularity).Results: Forty-two patients (mean age =65.33±12.51 years) with choroidal melanoma were included in the study. Homogeneity was confirmed in 16 patients through ultrasound scan, in 19 patients through T1-WI sequence, in 21 patients through T2-WI sequence, and in 25 patients through T1-WI sequence + contrast (gadolinium). Patients with homogenous tumors presented with lower (P=0.0045) mean height than that of those with nonhomogenous tumors, whereas no statistically significant difference was found for base diameter measurements (P=0.056). Patients with tumors of high vascularity presented with greater mean height (P=0.000638) and greater mean base diameter compared with those with tumors of low vascularity (P=0.019543). RD was detected in 26 patients through T1-WI sequence, in 13 patients through T2-WI sequence, in 26 patients through T1-WI sequence + contrast, and in 32 patients through ultrasound scan, which proved to be the most sensitive modality.Conclusion: The height of choroidal melanoma was positively correlated with tumor’s homogeneity. Melanomas of greater height were found to be less homogenous, due to increased degeneration and higher occurrence of intratumoral hemorrhage. In addition, choroidal melanoma’s height was also positively correlated with the level of its vascularity. Finally, ultrasound scan was found to be more sensitive than MRI in the detection of RD. Keywords: homogeneity, vascularity, ultrasound scan, MRI, imaging characteristics, retinal detachmen

    Measurements of elastic modulus for human anterior lens capsule with atomic force microscopy: The effect of loading force

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    The purpose of the study was to appraise the effect of loading force magnitude on the determination of the elastic modulus of the anterior lens capsule through atomic force microscopy. Four human anterior lens capsules taken during phacoemulsification cataract surgery were studied, free of epithelial cells, with atomic force microscopy. For the experiment, five different indentation loading forces were applied to near areas of the specimen. Experimental data was exported and analyzed according to the Hertz model to obtain the Young's modulus with regards to the elastic behavior of the material. Force-distance curves were acquired by applying a load of 2, 5, 10, 20 and 30 nN. When examining the results it was evident that determination of Young's modulus of the anterior lens capsule is dependent on the loading force concerning the examined range. Loading forces of 10 and 20 nN led to results without significant difference (p > 0.05) and more reproducible (coefficients of variation 12.4 and 11.7%, respectively). © Springer Science+Business Media Dordrecht 2013

    Contribution of integrated teaching in the improvement of an undergraduate ophthalmology curriculum

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    Ioannis T Tsinopoulos, Chrysanthos Symeonidis, Konstantinos T Tsaousis, Asimina Mataftsi, Nikolaos Chalvatzis, Argyrios Tzamalis, Lampros P Lamprogiannis, Stavros A Dimitrakos2nd Department of Ophthalmology, Medical School, Aristotle University of Thessaloniki, Thessaloniki, Macedonia, GreecePurpose: Conventional medical curriculum is the rule of medical teaching in Greek Medical Schools. Medical students are often taught irrelevant details with little or no reference to their potential clinical significance. Alternatively, integrated teaching warrants that the complete teaching material is covered by each faculty member not considering areas of personal expertise. The aim of this study was to evaluate the implementation of integrated teaching in ophthalmic training.Methods: The main outcome measures of this retrospective study were a) comments and recommendations made anonymously by the fifth-year medical students in the evaluation questionnaires filled in at the end of their training, and b) scores obtained by students in their final examination at the end of their training in the 2nd Department of Ophthalmology as part of the core Curriculum of the Medical School of the Aristotle University of Thessaloniki. The latter outcome was analyzed with respect to the implementation of integrated teaching.Results: The score obtained by students in the final examination, which is an objective outcome measure, increased significantly after the implementation of integrated teaching. The final grade (scores out of 10) of students who were trained with the integrated system (6.17±1.67, mean ± standard deviation) was significantly higher compared to those (5.52±2.20) trained with the conventional system (P<0.001). The positive outcome of this process was evident as there was a significant increase in the number of students satisfied with the teaching process compared to previous academic years.Conclusion: Based on the experience of eight academic years and as a result of interactive assessment process our department has modified its medical student teaching process from conventional to integrated; all teaching staff members are involved in the teaching process, while students are divided in small groups. In conclusion, integrated teaching in small student groups appears to be an efficient teaching method (for both theoretical and clinical skills) of ophthalmic training for medical students.Keywords: medical teaching, integrated teaching, medical training assessmen

    Bimanual anterior segment revision surgery for anterior capsule contraction syndrome associated with anterior flexion of intraocular lens haptics

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    PURPOSE To report the incidence of anterior capsule contraction syndrome (ACCS) and to present a novel minimally invasive bimanual technique for anterior segment revision surgery associated with ACCS with anterior flexion of the intraocular lens haptics. METHODS A consecutive cohort of 268 eyes of 161 patients undergoing phacoemulsification and implantation of the same type of hydrophilic acrylic aspheric intraocular lens cohort were analysed and a novel technique of minimally invasive bimanual technique for anterior segment revision surgery is described. RESULTS We identified four eyes (1.5%) of three patients with advanced ACCS. Successful restoration of a clear visual axis with minimal induction of astigmatism and rapid visual rehabilitation was achieved in all four cases. CONCLUSION This technique is a safe and minimally invasive alternative to laser or vitrector-cut capsulotomy to restore a clear visual axis. In cases of advanced ACCS, it offers the option for haptic reposition or amputation
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