Digital orbitoplethysmograph: A new device to study the regional cerebral circulation using extraorbital plethysmography.

BACKGROUND: Noninvasive diagnostic methods utilizing pulse wave measurements on the surface of the head are an important tool in diagnosing various types of cerebrovascular disease. The measurement of extraorbital pressure fluctuations reflects intraocular and intracranial pressure changes and can be used to estimate pressure changes in intracranial arteries and the collateral circulation. NEW METHOD: In this paper, we describe our patented (CZ 305757) digital device for noninvasive measuring and monitoring of orbital movements using pressure detection. We conducted preclinical tests (126 measurements on 42 volunteers) to evaluate the practical capabilities of our device. Two human experts visually assessed the quality of the pressure pulsation and discriminability among various test conditions (specifically, subject lying, sitting, and the Matas carotid occlusion test). RESULTS: The results showed that our device provided clinically relevant outcomes with a sufficient level of detail of the pulse wave and a high reliability (not less than 85%) in all clinically relevant situations. It was possible to record the effect of the Matas carotid occlusion test. COMPARISON WITH EXISTING METHOD(S): Our fully noninvasive, lightweight (185 g), portable, and wireless device provides a considerably cheaper alternative to the current diagnostic methods (e.g., transcranial ultrasound, X-ray, or MRI angiography) for specific assessment of cerebral circulation. Within a minute, it can detect the Willis circle integrity and thus eliminate the potential risks associated with the Matas test using standard EEG. CONCLUSIONS: Our device represents an improvement and a valid alternative to the current methods diagnosing regional cerebral circulation.

On-line integration of computer controlled diagnostic devices and medical information systems in undergraduate medical physics education for physicians.

We designed and evaluated an innovative computer-aided-learning environment based on the on-line integration of computer controlled medical diagnostic devices and a medical information system for use in the preclinical medical physics education of medical students. Our learning system simulates the actual clinical environment in a hospital or primary care unit. It uses a commercial medical information system for on-line storage and processing of clinical type data acquired during physics laboratory classes. Every student adopts two roles, the role of 'patient' and the role of 'physician'. As a 'physician' the student operates the medical devices to clinically assess 'patient' colleagues and records all results in an electronic 'patient' record. We also introduced an innovative approach to the use of supportive education materials, based on the methods of adaptive e-learning. A survey of student feedback is included and statistically evaluated. The results from the student feedback confirm the positive response of the latter to this novel implementation of medical physics and informatics in preclinical education. This approach not only significantly improves learning of medical physics and informatics skills but has the added advantage that it facilitates students' transition from preclinical to clinical subjects.

Cytochrome P450 2D6 polymorphism and drug utilization in patients with oral lichen planus.

OBJECTIVE: Oral lichen planus (OLP) is one of the commonest diseases of the oral mucosa. The etiology of the disease is unknown. Our goal was to determine frequencies of functionally important alleles which determine the metabolic rate (phenotype) of individuals with OLP and to compare drug utilization, with focus on CYP2D6, with that of a control group. MATERIAL AND METHODS: The study population consisted of 46 patients with OLP, 60 sex- and age-matched control subjects for drug utilization evaluation and 223 healthy non-medicated controls for genotype comparison. DNA analysis was done using polymerase chain reaction and restriction fragment length polymorphism. The gene CYP2D6 was analyzed for the alleles CYP2D6*3,*4,*5,*6 and gene duplication. Drug utilization was evaluated according to Anatomical Therapeutic Chemical code, liver drug metabolism pathway and mono- or polytherapy. RESULTS: Intake of drugs was significantly higher in the group of OLP patients in comparison with control subjects. The use of CYP2D6 substrates, inhibitors or inducers did not differ between OLP patients and controls. Predicted phenotype frequencies in OLP patients and healthy controls, respectively were as follows: ultrarapid metabolizers 2% and 5.8%, extensive metabolizers 52% and 49.8%, intermediate metabolizers 39% and 37.7% and poor metabolizers 7% and 6.7%. CONCLUSIONS: We did not find a statistically significant difference in the frequency of CYP2D6 alleles between OLP patients and healthy controls. OLP patients used more medication than age- and sex-matched controls.

WAA apheresis registry in the Czech Republic: two centers experience.

INTRODUCTION: Hemaphereses are sophisticated procedures performed for many indications even in severely ill patients. Many authors consider quite necessary to register as many details as possible of treatments with therapeutic apheresis. WAA meets the requirement to compare data with centers not performing apheresis for the same diagnosis. In Czech Republic hemaphereses are used in a broad spectrum of indications. Since the year 2004 data on hemaphereses done in Czech Republic have been registered. In this paper we present a survey of our to date recordings. PATIENTS AND METHODS: Data of performed therapeutic hemaphereses (plasma exchange, erythrocytapheresis, leukapheresis, thrombocytapheresis, photopheresis, immunopheresis, and rheopheresis) have been entered in WAA registry with many details. We have been evaluated 1289 procedures in 216 patients done in our two centers (center I, center II). RESULTS: Center I registered 129 procedures in 41 patients, center II 1260 procedures in 175 patients. The patients are divided according to centers specialization (center II has registered 12 long-term treated patients with LDL-apheresis; mean time of therapy 7.1 years and a median of 34 procedures/patient. Side-effects registered in center I and center II were 3.1% and 5.6% of the procedures, respectively. Most frequent side-effects were citrate toxicity, neurovegetative lability, problems with venous access and hypotension. All were easy to treat, no serious events or death occurred. CONCLUSIONS: In Czech Republic hemaphereses are performed in a broad scale of indications and now it is nearly 5 years that data are registered in our two university centers. In 2004 we entered WAA registry because it meets the requirement to compare data with centers that do not perform aphereses for the same diagnosis. This comparison would certainly improve efficacy of the hemapheresis therapy even further. To enter WAA registry is easy, at no expense and without any problems.

Elevated serum soluble endoglin (sCD105) decreased during extracorporeal elimination therapy for familial hypercholesterolemia.

Extracorporeal elimination is a method of LDL-lowering therapy that is used in severe familial hypercholesterolemia (FH) after other therapeutic approaches have failed. There are currently no universally accepted biomarkers that would allow determining necessary intensity of therapy and frequency of future therapeutic interventions. An ideal tool for immediate evaluation would be a readily measurable serum marker. We hypothesized that soluble endoglin (sCD105), a recently described indicator of endothelial dysfunction, may represent such a tool. Eleven patients with FH (three homozygous, eight heterozygous; Fredrickson type IIa, IIb) that have been monitored for 4.5+/-2.8 years were treated; eight by LDL-apheresis and three by hemorheopheresis. 40 sCD105 measurements were done, before and after two consecutive elimination procedures. Baseline serum sCD105 levels were significantly higher in the patients (5.74+/-1.47 microg/l in series I, 6.85+/-1.85 microg/l in series II) than in the control group (3.85+/-1.25 microg/l). They decreased to normal after LDL-elimination (p=0.0003) in all except for one patient. This return to normal was not due to a non-specific capture of endoglin in adsorption or filtration columns as demonstrated by measurement of sCD105 before and after passage through the elimination media. We conclude that the soluble endoglin levels in patients with severe FH remain elevated despite long-term intensive therapy and that they decrease after extracorporeal elimination. Endoglin can therefore serve as a marker for evaluation of the treatment efficacy and of the decreased atherosclerotic activity in patients with FH treated by extracorporeal LDL-cholesterol elimination.

Optimization of therapeutic procedure during LDL-apheresis - verification of the computerized model in clinical practice.

UNLABELLED: LDL-apheresis is a very effective method in the treatment of resistant hypercholesterolemia when other therapies fail. To maximize the efficacy of the use of LDL-absorbers, we created a computerized model. The aim of this study is to verify it in clinical use. PATIENTS AND METHODS: A therapeutic technique of immunoadsorption was used, applying a pair of Lipopak columns (Pocard, Russia). Plasma was separated by a continuous-flow plasma separator (Cobe Spectra, USA); adsorption was controlled by adsorption-desorption equipment Adasorb (Medicap, Germany). 494 LDL-apheresis procedures had been performed in nine patients with primary hypercholesterolemia in the earlier, initial study; 47 other procedures (202 therapeutic cycles) were used in this verification study. The program for procedure planning uses Microsoft Excel for Windows. Complex metabolism of the LDL-cholesterol was neglected (owing to the short-time period of the procedure) and the procedure calculated as continuous filtration. The input enterer into the program includes basic patient data (mass, height, sex and initial plasma LDL level in mmol/L). RESULTS: The results show a very good match between calculated levels and the real laboratory results in most procedures, but in some procedures we observed minor differences (0.05 mmol/L), which was caused by procedure adjustments due to technical reasons. However, some methodological and medical details must be carefully observed (initial cholesterol level, correct calculation of plasma volume, and the precise capacity of adsorbers that must not be overshot); as they influence the correct match between calculated and real results significantly. CONCLUSIONS: Although our software uses a fairly simplified model of the LDL-cholesterol kinetics during the LDL-apheresis, it is providing a great aid in the procedure planning. It is also suitable for practical use because it only requires a few commonly used and readily available input values.

Prognostic significance of ischemia modified albumin after percutaneous coronary intervention.

UNLABELLED: Ischemia modified albumin (IMA) is a new biochemical marker of ischemia. IMA levels rise in patients who develop ischemia during percutaneous coronary intervention (PCI). It is unclear whether IMA elevations correlate with PCI variables. The possible prognostic value of post-PCI IMA elevation has not yet to be studied. METHODS: We studied 60 patients (mean age 61 years; 51 male) who underwent successful elective single-vessel PCI for the management of stable angina pectoris. IMA levels were measured and compared with PCI variables and target lesion revascularization rate. The median post-PCI follow up is 46 months (CI 44.6 to 47.7). RESULTS: We found that the only variable related to post-PCI IMA levels was periprocedural dissection of target vessel (147.6 vs. 141.1 kU/l, p=0.035). No correlation between high and low balloon inflation pressure (143.6 vs. 141.6 kU/l, p=0.64), short and long inflation pressure (141.5 vs. 143.6 kU/l, p=0.17), with and without stent placement (143.7 vs. 141.3 kU/l, p=0.93) was found. IMA level more then 130 kU/l was associated with higher frequency of target lesion revascularization at nearly 4-years follow-up (p=0.026). CONCLUSION: Post-PCI IMA elevation is associated with higher target lesion revascularization.

Optimization of the therapeutic procedure during LDL-apheresis--a computerized model.

UNLABELLED: LDL-apheresis is a very effective method for the treatment of resistant hypercholesterolemia when other therapy (dietary, or medication) fails. To maximize the efficacy of the LDL-absorbers we aimed to create a computerized model. PATIENTS AND METHODS: The therapeutic technique of immunoadsorption was used, applying a pair of columns, the Lipopak, Pocard, Russia. Plasma was separated by a continuous-flow plasma separator, the Cobe Spectra, USA; adsorption was controlled by adsorption-desorption equipment, ADA, Medicap, Germany. 494 LDL-apheresis procedures (treatment interval 17.5+/-1.6 days) were used to treat nine patients with primary hypercholesterolemia followed during the consecutive 3.6+/-0.5 years. Metabolism of LDL-cholesterol is known to be multicompartmental and dynamic, but for the short-time period of the procedure it can be simplified and one can calculate the procedure as a continuous filtration. We developed a program for procedure planning, using Microsoft Excel for Windows. Inputs inserted into the program include only basic patient data (mass, height, sex and initial plasma LDL level in mmol/l). RESULTS: The results show a very promising match between our planning of the procedures and the real laboratory results. The drop in calculated vs real plasma LDL-cholesterol level differ no more than +/-10%. CONCLUSIONS: Although our software does not take into account many well known details about the metabolism of cholesterol, in given conditions it can provide a fairly precise prediction of procedure parameters. It is also suitable for practical use, because it requires only a few commonly used and readily available input values. Immunoadsorption with Pocard absorbers is a potent and safe method of therapy in indicated patients.