Stereotactic irradiation on linear accelerator - ultrasound versus MRI in choroidal melanoma volume calculation.

BACKGROUND: Stereotactic irradiation is one of the treatment modalities for intraocular uveal melanoma. The study's purpose was to describe the background of stereotactic one-day session radiosurgery, how the comparison in the difference between the tumor volume measured values from the magnetic resonance imaging (MRI) method and the ultrasound method was related to it, and which method was more precise to be used for tumor regression after irradiation. METHODS: The group of 147 patients with choroidal melanoma was treated by stereotactic irradiation on the linear accelerator with a single dose of 35.0 Gy. During the standard treatment process the uveal melanoma volumes, needed for dose calculation, were obtained using MRI from the individual stereotactic planning scheme and by ultrasound from the ultrasound device. All volumes were statistically compared using the paired t-test, and for the visualization purpose, the Bland-Altman plot was used. RESULTS: In the group of patients, it was 70 (47.6%) males and 77 (52.4%) females. The tumor volume median was from MRI equal to 0.44 cm3 and from ultrasound equal to 0.53 cm3. The difference between the ultrasound and the MRI volume measured values was statistically significant. However, the Bland-Altman plot clearly documents that the two methods are in agreement and can be used interchangeably. In most of the cases, the measured values of the ultrasound-calculated volume achieved slightly higher measured values. CONCLUSIONS: The calculation of the intraocular uveal tumor volume is a crucial part of the stereotactic irradiation treatment. The ultrasound volume measured values were in most of the cases higher than the measured values from the MRI. Although the methods are comparable and can be used interchangeably, we are recommending using the more precise MRI method not only during the treatment but also on later regular medical checks of tumor regression or progression.

A New Payload Swing Angle Sensing Device and Its Accuracy.

Measuring the swing angle of a crane load is a relatively well-known but unsatisfactorily solved problem in technical practice. This measurement is necessary for the automatic stabilization of load swing without human intervention. This article describes a technically simple and new approach to solving this problem. The focus of this work is to determine the accuracy of the measuring device. The focus of this work remains on the design, the principle of operation of the equipment, and the determination of accuracy. The basic idea is to apply the strain gauge on an elastic, easily deformable component that is part of the device. One part of the elastic component is fixedly connected to the frame; the other part is connected to the crane rope by means of pulleys close to the rope. In this way, the bending of the elastic component in proportion to the swing angle of the payload is ensured.

Two 11-Years Periods Statistics and Trends of Enucleation and Evisceration.

PURPOSE: The indications for evisceration and enucleation are still evolving and controversial. The study aims to describe trends of enucleation versus evisceration in one center. METHODS: In period 1998-2019 were 353 patients were included in the study. Statistical results and Chi-square test for pair-wise comparisons for the statistical significance in comparing two subgroups (years periods 1998-2008 and 2009-2019) per category have been evaluated. RESULTS: The enucleation was performed in 306 patients, and the evisceration was performed in 47 patients. In 221 patients with the tumor exclusively enucleation was indicated. For the operation technique, the authors got a chi-square value of 0.027, and the associated P value is at 0.8695, then the number of evisceration and enucleation in subgroups have not confirmed independency. For the tumor presence, the authors got a chi-square value of 5.4, and the associated P value is at 0.02, then the number of validated/nonvalidated tumor presence in subgroups confirmed independency. CONCLUSIONS: The performed enucleations had 98% cases uveal melanoma, 1% of cases of another type of malignancy (lymphoma non-Hodgkin type), and 1% cases with benign tumor. Enucleation is also today most frequently due to malignant intraocular tumors, whereas evisceration if most frequently for the phthisis eye after a trauma or a previous intraocular surgery. In our study in 22 years interval also in the second period, there was an increased trend of enucleation due to intraocular malignancy. It can have many reasons, especially, that patients are sent to oncology centers late in the advanced stage of tumor.

Intelligent Dynamic Identification Technique of Industrial Products in a Robotic Workplace.

The article deals with aspects of identifying industrial products in motion based on their color. An automated robotic workplace with a conveyor belt, robot and an industrial color sensor is created for this purpose. Measured data are processed in a database and then statistically evaluated in form of type A standard uncertainty and type B standard uncertainty, in order to obtain combined standard uncertainties results. Based on the acquired data, control charts of RGB color components for identified products are created. Influence of product speed on the measuring process identification and process stability is monitored. In case of identification uncertainty i.e., measured values are outside the limits of control charts, the K-nearest neighbor machine learning algorithm is used. This algorithm, based on the Euclidean distances to the classified value, estimates its most accurate iteration. This results into the comprehensive system for identification of product moving on conveyor belt, where based on the data collection and statistical analysis using machine learning, industry usage reliability is demonstrated.

SISCOM and FDG-PET in patients with non-lesional extratemporal epilepsy: correlation with intracranial EEG, histology, and seizure outcome.

AIMS: To assess the practical localising value of subtraction ictal single-photon emission computed tomography (SISCOM) coregistered with MRI and (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) in patients with extratemporal epilepsy and normal MRI. METHODS: We retrospectively studied a group of 14 patients who received surgery due to intractable epilepsy and who were shown to have focal cortical dysplasia, undetected by MRI, based on histological investigation. We coregistered preoperative SISCOM and PET images with postoperative MRI and visually determined whether the SISCOM focus, PET hypometabolic area, and cerebral cortex, exhibiting prominent abnormalities on intracranial EEG, were removed completely, incompletely, or not at all. These results and histopathological findings were compared with postoperative seizure outcome. RESULTS: Two patients underwent one-stage multimodal image-guided surgery and the remaining 12 underwent long-term invasive EEG. SISCOM findings were localised for all but 1 patient. FDG-PET was normal in 3 subjects, 2 of whom had favourable postsurgical outcome (Engel class I and II). Complete resection of the SISCOM focus (n=3), the area of PET hypometabolism (n=2), or the cortical regions with intracranial EEG abnormalities (n=7) were predictive of favourable postsurgical outcome. Favourable outcome was also encountered in: 4 of 8 patients with incomplete resection and 1 of 2 with no resection of the SISCOM focus; 4 of 7 patients with incomplete resection and 1 of 2 with no resection of the PET hypometabolic area; and 2 of 7 patients with incomplete resection of the area corresponding to intracranial EEG abnormality. No correlation between histopathological FCD subtype and seizure outcome was observed. CONCLUSION: Complete resection of the dysplastic cortex localised by SISCOM, FDG-PET or intracranial EEG is a reliable predictor of favourable postoperative seizure outcome in patients with non-lesional extratemporal epilepsy.

Calretinin, parvalbumin and calbindin immunoreactive interneurons in perirhinal cortex and temporal area Te3V of the rat brain: qualitative and quantitative analyses.

The perirhinal cortex (PRC) composed of areas 35 and 36 forms an important route for activity transfer between the hippocampus-entorhinal cortex and neocortex. Its function in memory formation and consolidation as well as in the initiation and spreading of epileptic activity was already partially elucidated. We studied the general pattern of calretinin (CR), parvalbumin (PV) and calbindin (CB) immunoreactivity and its corrected relative optical density (cROD) as well as morphological features and density of CR and PV immunoreactive (CR+, PV+) interneurons in the rat PRC. Neighboring neocortical association area Te3V was analyzed as well. The PRC differed from the Te3V in higher CR and lower PV overall immunoreactivity level. On CR immunostained sections, the difference between high cROD value in area 35 and low cROD value in area Te3V reached statistical significance (p<0.05). The pattern of CB immunoreactivity was similar to that of the neocortex. Vertically oriented bipolar neurons were the most common morphological type of CR+ neurons, multipolar neuronal morphology was typical among PV+ neurons and vertically oriented bipolar neurons and multipolar neurons were approximately equally frequent among CB+ neurons. The density of CR+ and PV+ neurons was stereologically measured. While the density of PV+ neurons was not significantly different in PRC when compared to Te3V, density of CR+ neurons in area 35 was significantly higher by comparison with Te3V (p<0.05). Further, the overall neuronal density was measured on Nissl stained sections and the proportion of CR+ and PV+ interneurons was expressed as a percentage of the total neurons counts. The percentage of CR+ interneurons was higher in area 35 by comparison with area Te3 (p<0.05), while the percentage of PV+ interneurons did not significantly differ among the examined areas. In conclusion, the PRC possesses specific interneuronal equipment with unusually high proportion of CR+ interneurons, what might be of importance for the presumed gating function of PRC in normal and diseased states.