VISUAL FUNCTIONS AFTER IMPLANTATION OF ACRYSOF MONOFOCAL INTRAOCULAR LENSES.

PURPOSE: The purpose of the study was to evaluate the visual functions after implantation of Acrysof monofocal intraocular lenses Alcon (SA60AT. MA50BM a SN60WF a SN6AT). MATERIALS AND METHODS: Four works are presented in the overview. The first work deals with the effect of eye length. corneal optic power and anterior chamber depth on the uncorrected near visual acuity (UNVA) after IOL implantation. The second work compares the effect of eye position (horizontal and vertical) on the final UNVA. The third work deals with the influence of the spherical lenses (SA and MA) and yellow aspherical lenses (SN) on UNVA. The later work examines the effect of pupil width on UNVA.    Results: The first work showed the dependence of eye axial length (the largest in eyes bellow 22.5 mm. r=0.36) on UNVA.  77.4 % of eyes with axial length below 22.5 mm had UNVA better than 0.5 and 70.49 % of all evaluated eyes had UNVA better than 0.5. Uncorrected far visual acuity (UDVA) better than 1.0 was in 97.54 % eyes in the whole group. In the second work we found a mean correlation in eyes shorter than 22.5 mm with UNVA in horizontal position (r=0.39) and in the vertical position (r=0.49). UNVA improved in these eyes in horizontal position from 0.53 to 0.58 in vertical position of the eye. In all eyes from the group UNVA changed from 0.51 to 0.56. The third work demonstrated the effect of sphericity and chromaticity on UNVA. Better than 0.5 in the group of eyes shorter than 22.5 mm in SA IOL in 67 % and in SN IOL in 60 %. In eyes with mean axial length was UNVA better than 0.5 in SA IOL in 86.5 %. in MA IOL in 81 % and in SN IOL in 75 %. In eyes longer than 23.5 mm was UNVA better than 0.5 in SA IOL in 100 % of eyes, in MA IOL in 60 % and in SN IOL in 33 % of eyes. In the fourth work the effect of pupil size was not demonstrated. CONCLUSION: The works showed excellent results of UNVA and UDVA after implantation of Acrysof monofocal lenses.

The Difference between Ganglion Cell Complex and Nerve Fiber Layer in the Same Altitudinal Halves of the Retina in Hyper-tension and Normal-tension Glaucomas.

Nerve Fiber Layer (RNFL) measurements in the same altitudinal half of the eye in hyper-tension (HTG) and normal-tension glaucomas (NTG). MATERIALS AND METHODS: We examined both eyes in altogether 50 patients (100 eyes). The cohort was divided into two groups, in each of them; there were 25 patients with average age of 55.4 in the NTG group and 54.6 years in the HTG group. The NTG group consisted of 17 women of the average age of 55.35 (range, 25-75) years, and 8 men of the average age of 55.5 (range, 32-69) years. In the HTG group, there were 12 women of the average age of 53.25 (range, 34-69) years, and 13 men of the average age of 60.38 (range, 37-74) years. The criteria for including the patients into the groups were: the visual acuity at least 1.0 (20/20) with possible correction smaller than ± 3 diopters, and approximately identical changes in the visual fields in all patients with initial stage of the glaucoma disease; no other ophthalmic or neurological diseases. In patients in the NTG group, the diagnosis was confirmed by means of electrophysiological examination. The thickness of the GCC was measured by means of SD-OCT RTvue - 100, similarly as the RNFL. RESULTS: In the statistical survey of the GCC values in HTG and NTG in the same altitudinal halves of the retina we did not establish statistical significant difference. We obtained the same result in statistical evaluation of the RNFL in HTG and NTG groups in the same altitudinal halves of the retinas. Similarly, even after the subtraction the GCC from RNFL values in the same altitudinal halves of the retinas we did not establish statistically significant difference between both groups. CONCLUSION: The GCC and the RNFL examination values in the same altitudinal halves of the retinas did not establish statistically significant difference that would differ the patients with HTG from patients with NTG. Although, using the OCT, we did not confirm the differences in both diagnostic groups, it does not mean, that these differences do not exist and they may have several causes. Key words: Ganglion Cell Complex (GCC), Retinal Nerve Fiber Layer (RNFL), Hyper-Tension Glaucoma (HTG), Normal-Tension Glaucoma (NTG).

An anthropomorphic breathing phantom of the thorax for testing new motion mitigation techniques for pencil beam scanning proton therapy.

Motion-induced range changes and incorrectly placed dose spots strongly affect the quality of pencil-beam-scanned (PBS) proton therapy, especially in thoracic tumour sites, where density changes are large. Thus motion-mitigation techniques are necessary, which must be validated in a realistic patient-like geometry. We report on the development and characterisation of a dynamic, anthropomorphic, thorax phantom that can realistically mimic thoracic motions and anatomical features for verifications of proton and photon 4D treatments. The presented phantom is of an average thorax size, and consists of inflatable, deformable lungs surrounded by a skeleton and skin. A mobile 'tumour' is embedded in the lungs in which dosimetry devices (such as radiochromic films) can be inserted. Motion of the tumour and deformation of the thorax is controlled via a custom made pump system driving air into and out of the lungs. Comprehensive commissioning tests have been performed to evaluate the mechanical performance of the phantom, its visibility on CT and MR imaging and its feasibility for dosimetric validation of 4D proton treatments. The phantom performed well on both regular and irregular pre-programmed breathing curves, reaching peak-to-peak amplitudes in the tumour of <20 mm. Some hysteresis in the inflation versus deflation phases was seen. All materials were clearly visualised in CT scans, and all, except the bone and lung components, were MRI visible. Radiochromic film measurements in the phantom showed that imaging for repositioning was required (as for a patient treatment). Dosimetry was feasible with Gamma Index agreements (4%/4 mm) between film dose and planned dose >90% in the central planes of the target. The results of this study demonstrate that this anthropomorphic thorax phantom is suitable for imaging and dosimetric studies in a thoracic geometry closely-matched to lung cancer patients under realistic motion conditions.

[The Uncorrected Near Visual Acuity after the Monofocal Intraocular Lens Implantation]. / Nekorigovaná zraková ostrost do blízka po implantaci monofokální IOL.

Aim of the study was to evaluate retrospectively selected parameters, which influence the postoperative near visual acuity in a group of pseudophakic eyes of patients with Uncorrected Distance Visual Acuity (UDVA) and according to acquired results establish those, which mostly influenced good Uncorrected Near Visual Acuity (UNVA) after the implantation of monofocal IntraOcular Lens (IOL). Altogether, 122 pseudophakic eyes of 65patients were followed up, out of them in 57 patients both eyes were operated on. The frequency of visual acuity for three groups of operated eyes categorized according to the crucial parameter - eyes axial length (short, average, long) was evaluated. In each of groups, the average parameters (age, axial length, keratometry, and depth of the anterior chamber) were established, as well as relative frequency of postoperative uncorrected near visual acuity on conventionally used reading tables. The near visual acuity assessment for each eye separately was preformed in its horizontal position using the Zeiss table. The study did not confirm positive correlation of postoperative near visual acuity on the age of the patient, depth of the anterior chamber, nor the implanted IOL type. It was confirmed the presumption of optimal near visual acuity for eyes with axial length shorter than 23.5 mm, and in the process, between both parameters slightly negative correlation was found. On the other hand, middle positive correlation between uncorrected near visual acuity and central corneal power (in dioptres) in eyes with the axial length 22.5 - 23.5 mm was found. The study confirmed, that higher values of the central corneal power (in dioptres) and the high borderline value of the axial length up to 23.5 mm are the condition for optimal postoperative uncorrected near visual acuity after the implantation of monofocal intraocular lens.Key words: Uncorrected Near Visual Acuity (UNVA), monofocal intraocular lens, pseudoaccommodation.

The effectiveness of combined gating and re-scanning for treating mobile targets with proton spot scanning. An experimental and simulation-based investigation.

Organ motion is one of the major obstacles in radiotherapy and charged particle therapy. Even more so, the theoretical advantages of dose distributions in scanned ion beam therapy may be lost due to the interplay between organ motion and beam scanning. Several techniques for dealing with this problem have been devised. In re-scanning, the target volume is scanned several times to average out the motion effects. In gating and breath-hold, dose is only delivered if the tumour is in a narrow window of position. Experiments have been performed to verify if gating and re-scanning are effective means of motion mitigation. Dose distributions were acquired in a lateral plane of a homogeneous phantom. For a spherical target volume and regular motion gating was sufficient. However, for realistic, irregular motion or a patient target volume, gating did not reduce the interplay effect to an acceptable level. Combining gating with re-scanning recovered the dose distributions. The simplest re-scanning approach, where a treatment plan is duplicated several times and applied in sequence, was not efficient. Simulations of different combinations of gating window sizes and re-scanning schemes revealed that reducing the gating window is the most efficient approach. However, very small gating windows are not robust for irregular motion.

Experimental verification of motion mitigation of discrete proton spot scanning by re-scanning.

In order to be able to treat mobile tumours with active, scanned proton therapy, adequate motion mitigation techniques have to be applied. Re-scanning is such an approach, where the interplay effect between tumour motion and treatment delivery is statistically smeared out. Different re-scanning methods have been used for the irradiation of a spherical target volume and motion amplitudes of up to 10 mm. The resulting dose distributions have been captured in two dimensions by imaging a scintillating screen at the iso-centre for different motion starting phases. Dose inhomogeneity increased approximately linearly with motion amplitude, while the influence of motion period and direction was small. Re-scanning the whole target volume reduced the interplay effect more than re-scanning only the iso-energy layers. Even for 10 mm motion amplitude, no hot or cold spots were seen for 10 re-scans of the whole volume. A fast energy change and fast beam scanning is vital for this kind of re-scanning, as available on Gantry 2 at the Paul Scherrer Institute. For larger motion amplitudes, re-scanning should be combined with gating, breath-hold or tracking to reduce the internal target volume.

Nuclear spins and moments of Ga isotopes reveal sudden structural changes between N=40 and N=50.

Collinear laser spectroscopy was performed on Ga (Z=31) isotopes at ISOLDE, CERN. A gas-filled linear Paul trap (ISCOOL) was used to extend measurements towards very neutron-rich isotopes (N=36-50). A ground state (g.s.) spin I=1/2 is measured for 73Ga, being near degenerate with a 3/2{-} isomer (75 eV≲E{ex}≲1 keV). The 79Ga g.s., with I=3/2, is dominated by protons in the πf{5/2} orbital and in 81Ga the 5/2{-} level becomes the g.s. The data are compared to shell-model calculations in the f{5/2}pg{9/2} model space, calling for further theoretical developments and new experiments.

Nuclear charge radii of 7,9,10Be and the one-neutron halo nucleus 11Be.

Nuclear charge radii of ;{7,9,10,11}Be have been determined by high-precision laser spectroscopy. On-line measurements were performed with collinear laser spectroscopy in the 2s_{1/2}-->2p_{1/2} transition on a beam of Be+ ions. Collinear and anticollinear laser beams were used simultaneously, and the absolute frequency determination using a frequency comb yielded an accuracy in the isotope-shift measurements of about 1 MHz. Combining this with accurate calculations of the mass-dependent isotope shifts yields nuclear charge radii. The charge radius decreases from 7Be to 10Be and then increases for the halo nucleus 11Be. When comparing our results with predictions of ab initio nuclear-structure calculations we find good agreement. Additionally, the nuclear magnetic moment of 7Be was determined to be -1.3995(5)micro_{N} and that of 11Be was confirmed with an accuracy similar to previous beta-NMR measurements.

Occupational exposure in angiography (Prague workplaces).

The results of measurements, which were performed at angiography departments, are presented. The aim of this work was not only to assess patient exposure but also to perform a survey of the occupational exposures of physicians during common angiography examinations of the skull, chest, abdomen and limbs. Patient data, type of examination, fluoroscopy time, the whole number of film frames, dose-area product (Diamentor E) and physician dose (Stephen 6000) were also recorded. There are many factors influencing the level of measured exposures. They include input parameters of X ray performance (kV, mA, projection, diaphragms, ZOOM, type of record etc) and individual approach of the physicians. This paper contributes to the discussion about the increasing exposures of the physicians specialising in diagnostic and interventional angiography.

Phosphatidylglycerolphosphate synthase encoded by the PEL1/PGS1 gene in Saccharomyces cerevisiae is localized in mitochondria and its expression is regulated by phospholipid precursors.

The PEL1/PGS1 gene of the yeast Saccharomyces cerevisiae is essential for the viability of rho-/rho degrees mutants and the normal cardiolipin content of cells. The PEL1-GFP fusion gene has been found to complement the pel1/pgs1 mutation and its fluorescent protein was localized to mitochondria similarly to the beta-galactosidase activity of a protein encoded by the PEL1-lacZ fusion gene. The expression of the PEL1-lacZ reporter gene was repressed in cells grown in the presence of inositol and choline, reduced in the ino2 and ino4 strains, but constitutive in the opi1 null-mutant strain. The results demonstrate that Pel1p, playing a vital role in cells impaired in the mitochondrial DNA, is localized in the mitochondria and expressed in response to inositol and choline.

[The genetic contribution of cows to the prevalence of mastitis in the following generation]. / Genetický podíl krav na prevalenci mastitid v následující generaci.

Investigations of mastitis prevalence were performed in 1227 dam-daughter pairs during 1985-1988. From the records of the last 10 years, the findings concerning mammary gland were obtained. Six herds of agricultural co-operatives in the Brno region were investigated. In the early period the Bohemian Pied breed, later the crosses of this breed with Red Holstein and a low genetic proportion of Ayrshire cattle, dominated in the set of cows. Udder health was assessed using the clinical and bacteriological findings in individual udder quarters and the results of the rapid mastitis test NK. Based on this data, the cows were divided into two groups--resistant and susceptible. The lactation order in which the disease appeared for the first time was of great importance. The occurrence of the disease in daughters and udder health in dams were in a significant relation (P less than or equal to 0.01). While nearly 50% of daughters of susceptible dams were affected, it was only 25% in daughters of the resistant group. The assessment of heritability of resistance to mastitis was carried out on the principle of dam-daughter regression. The index of heritability h2 = 0.52 +/- 0.06 was calculated. The results show that the genetic contribution of dams to the susceptibility of daughters to mastitis is significant.

[Differences in susceptibility of cows, in half-sisters by the same sire to mastitis]. / Rozdíly ve vnímavosti krav, polosester po otcích, k onemocnení mlécné zlázy.

The set of 9,555 cows, Bohemian Spotted breed, was studied if the sires contributed significantly to higher resistance, or on the contrary to susceptibility, of daughters to mastitis. The study was performed in 67 groups of half-sisters. Statistically highly significant (P less than 0.01) and significant (P less than 0.05) differences were proved as regards the frequency of bacteriologically positive and negative half-sisters in 36 groups as compared with the frequency ratio of positive and negative animals in the population. The daughters of 20 sires were more influenced in the positive sense, i. e. they suffered from mastitis less frequently than the daughters of 16 sires with a higher occurrence of the disease.

The nosocomial and occupational hepatitis type B infection in a chest disease hospital. A prospective study.

The results of a prospective study of hepatitis B infections among the patients of a Chest Disease Hospital are reported. A thousand and sixteen patients admitted during the twelve months study period were screened for the Hepatitis B(Surface)-Antigen(HBsAg) on admission and during the stay and were kept under epidemiological surveillance for six months following the discharge. The HBsAg prevalence was 3.54% on admission and the cumulative infection rate during the follow up period was 12.64 per 100 patients. The HBsAg prevalence on admission was significantly higher in males than in females, the susceptibility to infection found in the course of the study was in both sexes similar. The majority of infections was inapparent with the ratio of 8.6:1 of inapparent to clinically manifested forms. The incidence of viral hepatitis among the personnel was comparable to the incidence among the personnel of other hospital departments.

Hepatitis B (surface) antigen and viral hepatitis in family contacts of acute hepatitis B patients.

The results of a follow up study among family contacts of acute hepatitis B patients are reported. The family members were tested for HBsAg in the time of hospitalization of the index case and after three months again, the families were kept under epidemiological surveillance for six months. 19 (4,54%) out of the 418 persons screened for the first time were HBsAg-positive. The highest prevalence of HBsAg-positive persons was found in the families of patients without history of parenteral exposure. 5 (1%) of family contacts were hospitalized from 2 to 4 months following admission of the index case. All were the spouses of index case patients and none of them had other history of parenteral exposures than blood sampling for purpose of this study. 2 (0,58%) cases of silent antigenaemia were found among the 344 persons examined at the second screening.