Mathematical techniques for the protection of patient's privacy in medical databases

In modern society, keeping the balance between privacy and public access to information is becoming a widespread problem more and more often. Valid data is crucial for many kinds of research, but the public good should not be achieved at the expense of individuals. While creating a central database of patients, the CSIOZ wishes to provide statistical information for selected institutions. However, there are some plans to extend the access by providing the statistics to researchers or even to citizens. This might pose a significant risk of disclosure of some private, sensitive information about individuals. This report proposes some methods to prevent data leaks. One category of suggestions is based on the idea of modifying statistics, so that they would maintain importance for statisticians and at the same time guarantee the protection of patient's privacy. Another group of proposed mechanisms, though sometimes difficult to implement, enables one to obtain precise statistics, while restricting such queries which might reveal sensitive information

Seven-year evaluation of idiopathic multiple retinal pigment epithelium detachments

Objective: To analyze a 7-year natural history of idiopathic multiple retinal pigment epithelium (RPE) detachment based on optical coherence tomography (OCT) images. Methods: Case report. SD-OCT imaging (Topcon 3D OCT-1000).Results: A 55-year-old female presented with three foci of pigment epithelium detachment (PED) in her left eye. Her past ophthalmic and medical history was uneventful. The patient’s visual acuity in both eyes was 1.0 throughout the follow-up period. Fluorescein angiography images are shown. Corresponding OCT scans illustrate natural history of the PED foci and retinal structure of the left eye. PED number, location, shape, size and morphology were analyzed. Initially, the dimensions of PEDs were stable, but then a tendency to fluctuate or flatten was observed. Eventually, the lesions have resolved completely. Apart from the detachments, no other structural abnormalities of the retina were found. No PEDs, but sub-, para- and perifoveal RPE protrusions and defects were detected in the right eye.Conclusions: In the hereby presented case:1. OCT proved to be suitable for diagnosis and monitoring of multiple PEDs. 2. Multiple idiopathic PEDs without involvement of the fovea were asymptomatic and regressed spontaneously. As such, they did not require any treatment. However, they were monitored due to potential risk for choroidal neovascularization or serous retinal detachment

LC-MS-Based Metabolic Fingerprinting of Aqueous Humor

Aqueous humor (AH) is a transparent fluid which fills the anterior and posterior chambers of the eye. It supplies nutrients and removes metabolic waste from avascular tissues in the eye. Proper homeostasis of AH is required to maintain adequate intraocular pressure as well as optical and refractive properties of the eye. Application of metabolomics to study human AH may improve knowledge about the molecular mechanisms of eye diseases. Until now, global analysis of metabolites in AH has been mainly performed using NMR. Among the analytical platforms used in metabolomics, LC-MS allows for the highest metabolome coverage. The aim of this study was to develop a method for extraction and analysis of AH metabolites by LC-QTOF-MS. Different protocols for AH preparation were tested. The best results were obtained when one volume of AH was mixed with one volume of methanol : ethanol (1 : 1). In the final method, 2 µL of extracted sample was analyzed by LC-QTOF-MS. The method allowed for reproducible measurement of over 1000 metabolic features. Almost 250 metabolites were identified in AH and assigned to 47 metabolic pathways. This method is suitable to study the potential role of amino acids, lipids, oxidative stress, or microbial metabolites in development of ocular diseases