A quantitative method to the analysis of MLC leaf position and speed based on EPID and EBT3 film for dynamic IMRT treatment with different types of MLC.

Science.gov (United States)

Li, Yinghui; Chen, Lixin; Zhu, Jinhan; Wang, Bin; Liu, Xiaowei

2017-07-01

A quantitative method based on the electronic portal imaging system (EPID) and film was developed for MLC position and speed testing; this method was used for three MLC types (Millennium, MLCi, and Agility MLC). To determine the leaf position, a picket fence designed by the dynamic (DMLC) model was used. The full-width half-maximum (FWHM) values of each gap measured by EPID and EBT3 were converted to the gap width using the FWHM versus nominal gap width relationship. The algorithm developed for the picket fence analysis was able to quantify the gap width, the distance between gaps, and each individual leaf position. To determine the leaf speed, a 0.5 × 20 cm 2 MLC-defined sliding gap was applied across a 14 × 20 cm 2 symmetry field. The linacs ran at a fixed-dose rate. The use of different monitor units (MUs) for this test led to different leaf speeds. The effect of leaf transmission was considered in a speed accuracy analysis. The difference between the EPID and film results for the MLC position is less than 0.1 mm. For the three MLC types, twice the standard deviation (2 SD) is provided; 0.2, 0.4, and 0.4 mm for gap widths of three MLC types, and 0.1, 0.2, and 0.2 mm for distances between gaps. The individual leaf positions deviate from the preset positions within 0.1 mm. The variations in the speed profiles for the EPID and EBT3 results are consistent, but the EPID results are slightly better than the film results. Different speeds were measured for each MLC type. For all three MLC types, speed errors increase with increasing speed. The analysis speeds deviate from the preset speeds within approximately 0.01 cm s -1 . This quantitative analysis of MLC position and speed provides an intuitive evaluation for MLC quality assurance (QA). © 2017 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

SU-E-T-205: MLC Predictive Maintenance Using Statistical Process Control Analysis.

Science.gov (United States)

Able, C; Hampton, C; Baydush, A; Bright, M

2012-06-01

MLC failure increases accelerator downtime and negatively affects the clinic treatment delivery schedule. This study investigates the use of Statistical Process Control (SPC), a modern quality control methodology, to retrospectively evaluate MLC performance data thereby predicting the impending failure of individual MLC leaves. SPC, a methodology which detects exceptional variability in a process, was used to analyze MLC leaf velocity data. A MLC velocity test is performed weekly on all leaves during morning QA. The leaves sweep 15 cm across the radiation field with the gantry pointing down. The leaf speed is analyzed from the generated dynalog file using quality assurance software. MLC leaf speeds in which a known motor failure occurred (8) and those in which no motor replacement was performed (11) were retrospectively evaluated for a 71 week period. SPC individual and moving range (I/MR) charts were used in the analysis. The I/MR chart limits were calculated using the first twenty weeks of data and set at 3 standard deviations from the mean. The MLCs in which a motor failure occurred followed two general trends: (a) no data indicating a change in leaf speed prior to failure (5 of 8) and (b) a series of data points exceeding the limit prior to motor failure (3 of 8). I/MR charts for a high percentage (8 of 11) of the non-replaced MLC motors indicated that only a single point exceeded the limit. These single point excesses were deemed false positives. SPC analysis using MLC performance data may be helpful in detecting a significant percentage of impending failures of MLC motors. The ability to detect MLC failure may depend on the method of failure (i.e. gradual or catastrophic). Further study is needed to determine if increasing the sampling frequency could increase reliability. Project was support by a grant from Varian Medical Systems, Inc. © 2012 American Association of Physicists in Medicine.

An independent dose calculation algorithm for MLC-based stereotactic radiotherapy

International Nuclear Information System (INIS)

Lorenz, Friedlieb; Killoran, Joseph H.; Wenz, Frederik; Zygmanski, Piotr

2007-01-01

We have developed an algorithm to calculate dose in a homogeneous phantom for radiotherapy fields defined by multi-leaf collimator (MLC) for both static and dynamic MLC delivery. The algorithm was developed to supplement the dose algorithms of the commercial treatment planning systems (TPS). The motivation for this work is to provide an independent dose calculation primarily for quality assurance (QA) and secondarily for the development of static MLC field based inverse planning. The dose calculation utilizes a pencil-beam kernel. However, an explicit analytical integration results in a closed form for rectangular-shaped beamlets, defined by single leaf pairs. This approach reduces spatial integration to summation, and leads to a simple method of determination of model parameters. The total dose for any static or dynamic MLC field is obtained by summing over all individual rectangles from each segment which offers faster speed to calculate two-dimensional dose distributions at any depth in the phantom. Standard beam data used in the commissioning of the TPS was used as input data for the algorithm. The calculated results were compared with the TPS and measurements for static and dynamic MLC. The agreement was very good (<2.5%) for all tested cases except for very small static MLC sizes of 0.6 cmx0.6 cm (<6%) and some ion chamber measurements in a high gradient region (<4.4%). This finding enables us to use the algorithm for routine QA as well as for research developments

The transcription factor Mlc promotes Vibrio cholerae biofilm formation through repression of phosphotransferase system components.

Science.gov (United States)

Pickering, Bradley S; Lopilato, Jane E; Smith, Daniel R; Watnick, Paula I

2014-07-01

The phosphoenol phosphotransferase system (PTS) is a multicomponent signal transduction cascade that regulates diverse aspects of bacterial cellular physiology in response to the availability of high-energy sugars in the environment. Many PTS components are repressed at the transcriptional level when the substrates they transport are not available. In Escherichia coli, the transcription factor Mlc (for makes large colonies) represses transcription of the genes encoding enzyme I (EI), histidine protein (HPr), and the glucose-specific enzyme IIBC (EIIBC(Glc)) in defined media that lack PTS substrates. When glucose is present, the unphosphorylated form of EIIBC(Glc) sequesters Mlc to the cell membrane, preventing its interaction with DNA. Very little is known about Vibrio cholerae Mlc. We found that V. cholerae Mlc activates biofilm formation in LB broth but not in defined medium supplemented with either pyruvate or glucose. Therefore, we questioned whether V. cholerae Mlc functions differently than E. coli Mlc. Here we have shown that, like E. coli Mlc, V. cholerae Mlc represses transcription of PTS components in both defined medium and LB broth and that E. coli Mlc is able to rescue the biofilm defect of a V. cholerae Δmlc mutant. Furthermore, we provide evidence that Mlc indirectly activates transcription of the vps genes by repressing expression of EI. Because activation of the vps genes by Mlc occurs under only a subset of the conditions in which repression of PTS components is observed, we conclude that additional inputs present in LB broth are required for activation of vps gene transcription by Mlc. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Monte Carlo study of MLC fields for cobalt therapy machine

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Komanduri M Ayyangar

2014-01-01

Full Text Available An automated Multi-Leaf Collimator (MLC system has been developed as add-on for the cobalt-60 teletherapy machines available in India. The goal of the present computational study is to validate the MLC design using Monte Carlo (MC modeling. The study was based on the Kirloskar-supplied Phoenix model machines that closely match the Atomic Energy of Canada Limited (AECL theratron-80 machine. The MLC is a retrofit attachment to the collimator assembly, with 14 non-divergent leaf pairs of 40 mm thick, 7 mm wide, and 150 mm long tungsten alloy plates with rounded edges and 20 mm tongue and 2 mm groove in each leaf. In the present work, the source and collimator geometry has been investigated in detail to arrive at a model that best represents the measured dosimetric data. The authors have studied in detail the proto-I MLC built for cobalt-60. The MLC field sizes were MC simulated for 2 × 2 cm 2 to 14 × 14 cm 2 square fields as well as irregular fields, and the percent depth dose (PDD and profile data were compared with ROPS† treatment planning system (TPS. In addition, measured profiles using the IMATRIXX system‡ were also compared with the MC simulations. The proto-I MLC can define radiation fields up to 14 × 14 cm΂ within 3 mm accuracy. The maximum measured leakage through the leaf ends in closed condition was 3.4% and interleaf leakage observed was 7.3%. Good agreement between MC results, ROPS and IMATRIXX results has been observed. The investigation also supports the hypothesis that optical and radiation field coincidence exists for the square fields studied with the MLC. Plots of the percent depth dose (PDD data and profile data for clinically significant irregular fields have also been presented. The MC model was also investigated to speed up the calculations to allow calculations of clinically relevant conformal beams.

Evaluating efficiency of coaxial MLC VMAT plan for spine SBRT

Energy Technology Data Exchange (ETDEWEB)

Son, Sang Jun; Mun, Jun Ki; Kim, Dae Ho; Yoo, Suk Hyun [Dept. of Radiation Oncology, Seoul National University Hospital, Seoul (Korea, Republic of)

2014-12-15

The purpose of the study is to evaluate the efficiency of Coaxial MLC VMAT plan (Using 273° and 350° collimator angle) That the leaf motion direction aligned with axis of OAR (Organ at risk, It means spinal cord or cauda equine in this study.) compare to Universal MLC VMAT plan (using 30° and 330 ° collimator angle) for spine SBRT. The 10 cases of spine SBRT that treated with VMAT planned by Coaxial MLC and Varian TBX were enrolled. Those cases were planned by Eclipse (Ver. 10.0.42, Varian, USA), PRO3 (Progressive Resolution Optimizer 10.0.28) and AAA (Anisotropic Analytic Algorithm Ver. 10.0.28) with coplanar 260 ° arcs and 10MV FFF (Flattening filter free). Each arc has 273° and 350 ° collimator angle, respectively. The Universal MLC VMAT plans are based on existing treatment plans. Those plans have the same parameters of existing treatment plans but collimator angle. To minimize the dose difference that shows up randomly on optimizing, all plans were optimized and calculated twice respectively. The calculation grid is 0.2 cm and all plans were normalized to the target V100%=90%. The indexes of evaluation are V10Gy, D0.03cc, Dmean of OAR (Organ at risk, It means spinal cord or cauda equine in this study.), H.I (Homogeneity index) of the target and total MU. All Coaxial VMAT plans were verified by gamma test with Mapcheck2 (Sun Nuclear Co., USA), Mapphan (Sun Nuclear Co., USA) and SNC patient (Sun Nuclear Co., USA Ver 6.1.2.18513). The difference between the coaxial and the universal VMAT plans are follow. The coaxial VMAT plan is better in the V10Gy of OAR, Up to 4.1%, at least 0.4%, the average difference was 1.9% and In the D0.03cc of OAR, Up to 83.6 cGy, at least 2.2 cGy, the average difference was 33.3 cGy. In Dmean, Up to 34.8 cGy, at least -13.0 cGy, the average difference was 9.6 cGy that say the coaxial VMAT plans are better except few cases. H.I difference Up to 0.04, at least 0.01, the average difference was 0.02 and the difference of average

Influence of MLC leaf width on biologically adapted IMRT plans

Energy Technology Data Exchange (ETDEWEB)

Roedal, Jan; Soevik, Aaste; Malinen, Eirik (Dept. of Medical Physics, The Norwegian Radium Hospital, Oslo Univ. Hospital, Oslo (Norway)), E-mail: jan.rodal@radiumhospitalet.no

2010-10-15

Introduction. High resolution beam delivery may be required for optimal biology-guided adaptive therapy. In this work, we have studied the influence of multi leaf collimator (MLC) leaf widths on the treatment outcome following adapted IMRT of a hypoxic tumour. Material and methods. Dynamic contrast enhanced MR images of a dog with a spontaneous tumour in the nasal region were used to create a tentative hypoxia map following a previously published procedure. The hypoxia map was used as a basis for generating compartmental gross tumour volumes, which were utilised as planning structures in biologically adapted IMRT. Three different MLCs were employed in inverse treatment planning, with leaf widths of 2.5 mm, 5 mm and 10 mm. The number of treatment beams and the degree of step-and-shoot beam modulation were varied. By optimising the tumour control probability (TCP) function, optimal compartmental doses were derived and used as target doses in the inverse planning. Resulting IMRT dose distributions and dose volume histograms (DVHs) were exported and analysed, giving estimates of TCP and compartmental equivalent uniform doses (EUDs). The impact of patient setup accuracy was simulated. Results. The MLC with the smallest leaf width (2.5 mm) consistently gave the highest TCPs and compartmental EUDs, assuming no setup error. The difference between this MLC and the 5 mm MLC was rather small, while the MLC with 10 mm leaf width gave considerably lower TCPs. When including random and systematic setup errors, errors larger than 5 mm gave only small differences between the MLC types. For setup errors larger than 7 mm no differences were found between non-uniform and uniform dose distributions. Conclusions. Biologically adapted radiotherapy may require MLCs with leaf widths smaller than 10 mm. However, for a high probability of cure it is crucial that accurate patient setup is ensured.

Fast regional readout CMOS Image Sensor for dynamic MLC tracking

Science.gov (United States)

Zin, H.; Harris, E.; Osmond, J.; Evans, P.

2014-03-01

Advanced radiotherapy techniques such as volumetric modulated arc therapy (VMAT) require verification of the complex beam delivery including tracking of multileaf collimators (MLC) and monitoring the dose rate. This work explores the feasibility of a prototype Complementary metal-oxide semiconductor Image Sensor (CIS) for tracking these complex treatments by utilising fast, region of interest (ROI) read out functionality. An automatic edge tracking algorithm was used to locate the MLC leaves edges moving at various speeds (from a moving triangle field shape) and imaged with various sensor frame rates. The CIS demonstrates successful edge detection of the dynamic MLC motion within accuracy of 1.0 mm. This demonstrates the feasibility of the sensor to verify treatment delivery involving dynamic MLC up to ~400 frames per second (equivalent to the linac pulse rate), which is superior to any current techniques such as using electronic portal imaging devices (EPID). CIS provides the basis to an essential real-time verification tool, useful in accessing accurate delivery of complex high energy radiation to the tumour and ultimately to achieve better cure rates for cancer patients.

Fast regional readout CMOS image sensor for dynamic MLC tracking

International Nuclear Information System (INIS)

Zin, H; Harris, E; Osmond, J; Evans, P

2014-01-01

Advanced radiotherapy techniques such as volumetric modulated arc therapy (VMAT) require verification of the complex beam delivery including tracking of multileaf collimators (MLC) and monitoring the dose rate. This work explores the feasibility of a prototype Complementary metal-oxide semiconductor Image Sensor (CIS) for tracking these complex treatments by utilising fast, region of interest (ROI) read out functionality. An automatic edge tracking algorithm was used to locate the MLC leaves edges moving at various speeds (from a moving triangle field shape) and imaged with various sensor frame rates. The CIS demonstrates successful edge detection of the dynamic MLC motion within accuracy of 1.0 mm. This demonstrates the feasibility of the sensor to verify treatment delivery involving dynamic MLC up to ∼400 frames per second (equivalent to the linac pulse rate), which is superior to any current techniques such as using electronic portal imaging devices (EPID). CIS provides the basis to an essential real-time verification tool, useful in accessing accurate delivery of complex high energy radiation to the tumour and ultimately to achieve better cure rates for cancer patients.

Implementation of a Quality Control using portal imaging dynamic MLC; Implementacion de un programa de control de calidad de MLC dinamico mediante imagen portal

Energy Technology Data Exchange (ETDEWEB)

Sanz Freire, C. J.; Vazquez Galinanes, A.; Collado Chamorro, P. M.; Diaz Pascual, V.; Gomez Amez, J.; Sanchez Martinez, S.; Ossola Lentati, G. A

2011-07-01

The precision in the correct beam irradiation in the treatment of highly modulated Intensity Modulated Radiation Therapy (IMRT) depends largely on the characteristics and behavior of the multi leaf collimator (MLC). Quality control (QC) of this element is essential to ensure proper delivery of the beams calculated. It is important to know the absolute position of each sheet, the motion characteristics of each behavior and stability. Among the numerous methods for carrying out the QC MLC, the use of portal imaging is a practical and high resolution. This paper describes the development of a quality control program based dynamic MLC portal image, self-developed software that enables analysis and the results of two years experience following the implementation of IMRT treatments at our center. (Author)

Implementation and acceptance of dynamic MLC for IMRT and VMAT; Implementacion y aceptacion de MLC dinamicos para IMRT y VMAT

Energy Technology Data Exchange (ETDEWEB)

Garcia, B.; Marquina, J.; Ramirez, J.; Gonzales, A., E-mail: bertha.garcia@aliada.com.pe [ALIADA, Oncologia Integral, Av. Jose Galvez Barrenechea 1044, San Isidro, Lima 27 (Peru)

2014-08-15

The use of Multi-leaf Collimator (MLC) in Intensity-Modulated Radiation Therapy (IMRT) for dynamic treatment techniques as Volumetric Modulated Arc Therapy (VMAT) makes that the movement controls as the speed of the MLC are quantified by means of an acceptance test. The objective determination of the operation regulations of the radiotherapy equipment requires ideally the establishment of the quantitative relationship among the performance deviations and clinical results or some acceptable substitute. Different protocols exist detailed with parameters and acceptance ranges according to the MLC thickness. In our case the acceptance test was carried out for 120-MLC of Trilogy equipment brand Varian. For all the test were used 300-200 Um for each formed beam lets; source-surface distance (SSD) of 100 cm. 9 acceptance tests were used each one with different purposes like to quantify, synchronization, stability, complexity, precision, positioning, conformity, dynamic movements for the case of dynamic wedges, consecutive moves, among others, for the measurements were used film badges dosimetry (Gafchromic Ebt-3 scanner Epson expression 10000 XL); additionally the results were compared with a diodes arrangement Map-Check 2 brand Sun Nuclear; that consists of 1527 diodes prepared in a field of 32 x 26 cm located at a distance of 1 cm parallel, 0.5 cm diagonally. All the developed tests were inside the acceptance tolerance parameters when comparing the obtained result regarding the badges and the Map-Check was found a discrepancy of 0.01%, what gives a treatment certainty to the moment to impart volumetric dose in dynamic fields to the patients. (Author)

An MLC calibration method using a detector array

International Nuclear Information System (INIS)

Simon, Thomas A.; Kahler, Darren; Simon, William E.; Fox, Christopher; Li, Jonathan; Palta, Jatinder; Liu, Chihray

2009-01-01

Purpose: The authors have developed a quantitative calibration method for a multileaf collimator (MLC) which measures individual leaf positions relative to the MLC backup jaw on an Elekta Synergy linear accelerator. Methods: The method utilizes a commercially available two-axis detector array (Profiler 2; Sun Nuclear Corporation, Melbourne, FL). To calibrate the MLC bank, its backup jaw is positioned at the central axis and the opposing jaw is retracted to create a half-beam configuration. The position of the backup jaws field edge is then measured with the array to obtain what is termed the radiation defined reference line. The positions of the individual leaf ends relative to this reference line are then inferred by the detector response in the leaf end penumbra. Iteratively adjusting and remeasuring the leaf end positions to within specifications completes the calibration. Using the backup jaw as a reference for the leaf end positions is based on three assumptions: (1) The leading edge of an MLC leaf bank is parallel to its backup jaw's leading edge, (2) the backup jaw position is reproducible, and (3) the measured radiation field edge created by each leaf end is representative of that leaf's position. Data from an electronic portal imaging device (EPID) were used in a similar analysis to check the results obtained with the array. Results: The relative leaf end positions measured with the array differed from those measured with the EPID by an average of 0.11 ±0.09 mm per leaf. The maximum leaf positional change measured with the Profiler 2 over a 3 month period was 0.51 mm. A leaf positional accuracy of ±0.4 mm is easily attainable through the iterative calibration process. The method requires an average of 40 min to measure both leaf banks. Conclusions: This work demonstrates that the Profiler 2 is an effective tool for efficient and quantitative MLC quality assurance and calibration.

An MLC calibration method using a detector array

Energy Technology Data Exchange (ETDEWEB)

Simon, Thomas A.; Kahler, Darren; Simon, William E.; Fox, Christopher; Li, Jonathan; Palta, Jatinder; Liu, Chihray [Department of Nuclear and Radiological Engineering, University of Florida, 202 Nuclear Science Building, Gainesville, Florida 32611-8300 (United States); Sun Nuclear Corporation, 425-A Pineda Court, Melbourne, Florida 32940 (United States) and Department of Radiation Oncology, Health Science Center, University of Florida, P.O. Box 100385, Gainesville, Florida 32610-0385 (United States); Department of Radiation Oncology, Health Science Center, University of Florida, P.O. Box 100385, Gainesville, Florida 32610-0385 (United States); Sun Nuclear Corporation, 425-A Pineda Court, Melbourne, Florida 32940 (United States); Department of Radiation Oncology, Tulane University, 1415 Tulane Ave, HC65, New Orleans, Louisiana 70112 (United States); Department of Radiation Oncology, Health Science Center, University of Florida, P.O. Box 100385, Gainesville, Florida 32610-0385 (United States)

2009-10-15

Purpose: The authors have developed a quantitative calibration method for a multileaf collimator (MLC) which measures individual leaf positions relative to the MLC backup jaw on an Elekta Synergy linear accelerator. Methods: The method utilizes a commercially available two-axis detector array (Profiler 2; Sun Nuclear Corporation, Melbourne, FL). To calibrate the MLC bank, its backup jaw is positioned at the central axis and the opposing jaw is retracted to create a half-beam configuration. The position of the backup jaws field edge is then measured with the array to obtain what is termed the radiation defined reference line. The positions of the individual leaf ends relative to this reference line are then inferred by the detector response in the leaf end penumbra. Iteratively adjusting and remeasuring the leaf end positions to within specifications completes the calibration. Using the backup jaw as a reference for the leaf end positions is based on three assumptions: (1) The leading edge of an MLC leaf bank is parallel to its backup jaw's leading edge, (2) the backup jaw position is reproducible, and (3) the measured radiation field edge created by each leaf end is representative of that leaf's position. Data from an electronic portal imaging device (EPID) were used in a similar analysis to check the results obtained with the array. Results: The relative leaf end positions measured with the array differed from those measured with the EPID by an average of 0.11 {+-}0.09 mm per leaf. The maximum leaf positional change measured with the Profiler 2 over a 3 month period was 0.51 mm. A leaf positional accuracy of {+-}0.4 mm is easily attainable through the iterative calibration process. The method requires an average of 40 min to measure both leaf banks. Conclusions: This work demonstrates that the Profiler 2 is an effective tool for efficient and quantitative MLC quality assurance and calibration.

SU-F-T-530: Characterization of a 60-Leaf Motorized MLC Designed for Cobalt-60 Units

International Nuclear Information System (INIS)

Xu, L; Smith, L; Ciresianu, A

2016-01-01

Purpose: In a continuing effort to improve conformal radiation therapy with Cobalt-60 units, a 60-leaf MLC was designed, manufactured, and released to market. This work describes the physics measurements taken to characterize the clinical performance of this MLC. Methods: A 60 leaf MLC was custom designed with tungsten leaves of 4.5 cm height, single focused, achieving field size of 30×30 cm^2 when mounted on a 100cm SAD Cobalt-60 unit. Leakage and output factor measurements were performed using a single ion chamber in a solid water phantom. Penumbra and surface dose were measured using scanning chambers and diodes in a water phantom. Radiation-light coincidence measurements were performed using radiographic films. Results: With MLC mounted, measured penumbras at all depths are smaller than with jaws only. Surface doses were not significantly affected by the presence of MLC, and remained below values recommended by regulatory bodies. Light-radiation coincidences were found to be better than 3 mm for all field sizes. Leakage through the MLC was found to be strongly dependent on field size, increasing from 1.0 % for a 10×10 cm field to 2.0% for a 30×30 cm field. Such results meet the requirements of IEC 60601-2-11. The MLC was found to have significant influence on the output factor, when field size defined by MLC is significantly smaller than field size defined by jaws. Such effect is also observed on linear accelerators, but it is more pronounced on Cobalt-60 units. A 10×10 “diamond” MLC shape inside a 14×14 cm jaw showed output factor that is 5.7% higher than 10×10 cm field defined by matching MLC and jaws. Conclusion: The MLC offers clinically acceptable performance in penumbra, surface dose, and light-radiation coincidence. Several units of this MLC have recently been installed and used clinically. Validation of Cobalt-60 based IMRT with this MLC is ongoing. The authors are employees of Best Theratrnics Ltd.

SU-F-T-530: Characterization of a 60-Leaf Motorized MLC Designed for Cobalt-60 Units

Energy Technology Data Exchange (ETDEWEB)

Xu, L; Smith, L; Ciresianu, A [Best Theratronics, Ottawa, ON (Canada)

2016-06-15

Purpose: In a continuing effort to improve conformal radiation therapy with Cobalt-60 units, a 60-leaf MLC was designed, manufactured, and released to market. This work describes the physics measurements taken to characterize the clinical performance of this MLC. Methods: A 60 leaf MLC was custom designed with tungsten leaves of 4.5 cm height, single focused, achieving field size of 30×30 cm^2 when mounted on a 100cm SAD Cobalt-60 unit. Leakage and output factor measurements were performed using a single ion chamber in a solid water phantom. Penumbra and surface dose were measured using scanning chambers and diodes in a water phantom. Radiation-light coincidence measurements were performed using radiographic films. Results: With MLC mounted, measured penumbras at all depths are smaller than with jaws only. Surface doses were not significantly affected by the presence of MLC, and remained below values recommended by regulatory bodies. Light-radiation coincidences were found to be better than 3 mm for all field sizes. Leakage through the MLC was found to be strongly dependent on field size, increasing from 1.0 % for a 10×10 cm field to 2.0% for a 30×30 cm field. Such results meet the requirements of IEC 60601-2-11. The MLC was found to have significant influence on the output factor, when field size defined by MLC is significantly smaller than field size defined by jaws. Such effect is also observed on linear accelerators, but it is more pronounced on Cobalt-60 units. A 10×10 “diamond” MLC shape inside a 14×14 cm jaw showed output factor that is 5.7% higher than 10×10 cm field defined by matching MLC and jaws. Conclusion: The MLC offers clinically acceptable performance in penumbra, surface dose, and light-radiation coincidence. Several units of this MLC have recently been installed and used clinically. Validation of Cobalt-60 based IMRT with this MLC is ongoing. The authors are employees of Best Theratrnics Ltd.

Electron beam collimation with a photon MLC for standard electron treatments

Science.gov (United States)

Mueller, S.; Fix, M. K.; Henzen, D.; Frei, D.; Frauchiger, D.; Loessl, K.; Stampanoni, M. F. M.; Manser, P.

2018-01-01

Standard electron treatments are currently still performed using standard or molded patient-specific cut-outs placed in the electron applicator. Replacing cut-outs and electron applicators with a photon multileaf collimator (pMLC) for electron beam collimation would make standard electron treatments more efficient and would facilitate advanced treatment techniques like modulated electron radiotherapy (MERT) and mixed beam radiotherapy (MBRT). In this work, a multiple source Monte Carlo beam model for pMLC shaped electron beams commissioned at a source-to-surface distance (SSD) of 70 cm is extended for SSDs of up to 100 cm and validated for several Varian treatment units with field sizes typically used for standard electron treatments. Measurements and dose calculations agree generally within 3% of the maximal dose or 2 mm distance to agreement. To evaluate the dosimetric consequences of using pMLC collimated electron beams for standard electron treatments, pMLC-based and cut-out-based treatment plans are created for a left and a right breast boost, a sternum, a testis and a parotid gland case. The treatment plans consist of a single electron field, either alone (1E) or in combination with two 3D conformal tangential photon fields (1E2X). For each case, a pMLC plan with similar treatment plan quality in terms of dose homogeneity to the target and absolute mean dose values to the organs at risk (OARs) compared to a cut-out plan is found. The absolute mean dose to an OAR is slightly increased for pMLC-based compared to cut-out-based 1E plans if the OAR is located laterally close to the target with respect to beam direction, or if a 6 MeV electron beam is used at an extended SSD. In conclusion, treatment plans using cut-out collimation can be replaced by plans of similar treatment plan quality using pMLC collimation with accurately calculated dose distributions.

Combining MLC and SVM Classifiers for Learning Based Decision Making: Analysis and Evaluations.

Science.gov (United States)

Zhang, Yi; Ren, Jinchang; Jiang, Jianmin

2015-01-01

Maximum likelihood classifier (MLC) and support vector machines (SVM) are two commonly used approaches in machine learning. MLC is based on Bayesian theory in estimating parameters of a probabilistic model, whilst SVM is an optimization based nonparametric method in this context. Recently, it is found that SVM in some cases is equivalent to MLC in probabilistically modeling the learning process. In this paper, MLC and SVM are combined in learning and classification, which helps to yield probabilistic output for SVM and facilitate soft decision making. In total four groups of data are used for evaluations, covering sonar, vehicle, breast cancer, and DNA sequences. The data samples are characterized in terms of Gaussian/non-Gaussian distributed and balanced/unbalanced samples which are then further used for performance assessment in comparing the SVM and the combined SVM-MLC classifier. Interesting results are reported to indicate how the combined classifier may work under various conditions.

Combining MLC and SVM Classifiers for Learning Based Decision Making: Analysis and Evaluations

Directory of Open Access Journals (Sweden)

Yi Zhang

2015-01-01

Full Text Available Maximum likelihood classifier (MLC and support vector machines (SVM are two commonly used approaches in machine learning. MLC is based on Bayesian theory in estimating parameters of a probabilistic model, whilst SVM is an optimization based nonparametric method in this context. Recently, it is found that SVM in some cases is equivalent to MLC in probabilistically modeling the learning process. In this paper, MLC and SVM are combined in learning and classification, which helps to yield probabilistic output for SVM and facilitate soft decision making. In total four groups of data are used for evaluations, covering sonar, vehicle, breast cancer, and DNA sequences. The data samples are characterized in terms of Gaussian/non-Gaussian distributed and balanced/unbalanced samples which are then further used for performance assessment in comparing the SVM and the combined SVM-MLC classifier. Interesting results are reported to indicate how the combined classifier may work under various conditions.

Comparison of MLC error sensitivity of various commercial devices for VMAT pre-treatment quality assurance.

Science.gov (United States)

Saito, Masahide; Sano, Naoki; Shibata, Yuki; Kuriyama, Kengo; Komiyama, Takafumi; Marino, Kan; Aoki, Shinichi; Ashizawa, Kazunari; Yoshizawa, Kazuya; Onishi, Hiroshi

2018-05-01

The purpose of this study was to compare the MLC error sensitivity of various measurement devices for VMAT pre-treatment quality assurance (QA). This study used four QA devices (Scandidos Delta4, PTW 2D-array, iRT systems IQM, and PTW Farmer chamber). Nine retrospective VMAT plans were used and nine MLC error plans were generated for all nine original VMAT plans. The IQM and Farmer chamber were evaluated using the cumulative signal difference between the baseline and error-induced measurements. In addition, to investigate the sensitivity of the Delta4 device and the 2D-array, global gamma analysis (1%/1, 2%/2, and 3%/3 mm), dose difference (1%, 2%, and 3%) were used between the baseline and error-induced measurements. Some deviations of the MLC error sensitivity for the evaluation metrics and MLC error ranges were observed. For the two ionization devices, the sensitivity of the IQM was significantly better than that of the Farmer chamber (P < 0.01) while both devices had good linearly correlation between the cumulative signal difference and the magnitude of MLC errors. The pass rates decreased as the magnitude of the MLC error increased for both Delta4 and 2D-array. However, the small MLC error for small aperture sizes, such as for lung SBRT, could not be detected using the loosest gamma criteria (3%/3 mm). Our results indicate that DD could be more useful than gamma analysis for daily MLC QA, and that a large-area ionization chamber has a greater advantage for detecting systematic MLC error because of the large sensitive volume, while the other devices could not detect this error for some cases with a small range of MLC error. © 2018 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

Dose domain regularization of MLC leaf patterns for highly complex IMRT plans

Energy Technology Data Exchange (ETDEWEB)

Nguyen, Dan; Yu, Victoria Y.; Ruan, Dan; Cao, Minsong; Low, Daniel A.; Sheng, Ke, E-mail: ksheng@mednet.ucla.edu [Department of Radiation Oncology, University of California Los Angeles, Los Angeles, California 90095 (United States); O’Connor, Daniel [Department of Mathematics, University of California Los Angeles, Los Angeles, California 90095 (United States)

2015-04-15

Purpose: The advent of automated beam orientation and fluence optimization enables more complex intensity modulated radiation therapy (IMRT) planning using an increasing number of fields to exploit the expanded solution space. This has created a challenge in converting complex fluences to robust multileaf collimator (MLC) segments for delivery. A novel method to regularize the fluence map and simplify MLC segments is introduced to maximize delivery efficiency, accuracy, and plan quality. Methods: In this work, we implemented a novel approach to regularize optimized fluences in the dose domain. The treatment planning problem was formulated in an optimization framework to minimize the segmentation-induced dose distribution degradation subject to a total variation regularization to encourage piecewise smoothness in fluence maps. The optimization problem was solved using a first-order primal-dual algorithm known as the Chambolle-Pock algorithm. Plans for 2 GBM, 2 head and neck, and 2 lung patients were created using 20 automatically selected and optimized noncoplanar beams. The fluence was first regularized using Chambolle-Pock and then stratified into equal steps, and the MLC segments were calculated using a previously described level reducing method. Isolated apertures with sizes smaller than preset thresholds of 1–3 bixels, which are square units of an IMRT fluence map from MLC discretization, were removed from the MLC segments. Performance of the dose domain regularized (DDR) fluences was compared to direct stratification and direct MLC segmentation (DMS) of the fluences using level reduction without dose domain fluence regularization. Results: For all six cases, the DDR method increased the average planning target volume dose homogeneity (D95/D5) from 0.814 to 0.878 while maintaining equivalent dose to organs at risk (OARs). Regularized fluences were more robust to MLC sequencing, particularly to the stratification and small aperture removal. The maximum and

Orthokeratinised odontogenic cyst mimicking periapical cyst

OpenAIRE

Rajalakshmi, R; Sreeja, C; Vijayalakshmi, D; Leelarani, V

2013-01-01

Orthokeratinised odontogenic cyst (OOC) denotes the odontogenic cyst that microscopically has an orthokeratinised epithelial lining. OOC is characterised by a less-aggressive behaviour and a low rate of recurrence. This report describes a case of OOC involving posterior part of the mandible that mimicked periapical cyst in a 14-year-old boy. The initial clinical diagnosis was given as periapical cyst based on the clinical and radiographical features. Enucleation of the cyst was performed and ...

Real-time dynamic MLC tracking for inversely optimized arc radiotherapy

DEFF Research Database (Denmark)

Falk, Marianne; af Rosenschöld, Per Munck; Keall, Paul

2010-01-01

Motion compensation with MLC tracking was tested for inversely optimized arc radiotherapy with special attention to the impact of the size of the target displacements and the angle of the leaf trajectory.......Motion compensation with MLC tracking was tested for inversely optimized arc radiotherapy with special attention to the impact of the size of the target displacements and the angle of the leaf trajectory....

State-Transition-Aware Spilling Heuristic for MLC STT-RAM-Based Registers

Directory of Open Access Journals (Sweden)

Yuanhui Ni

2017-01-01

Full Text Available Multilevel Cell Spin-Transfer Torque Random Access Memory (MLC STT-RAM is a promising nonvolatile memory technology to build registers for its natural immunity to electromagnetic radiation in rad-hard space environment. Unlike traditional SRAM-based registers, MLC STT-RAM exhibits unbalanced write state transitions due to the fact that the magnetization directions of hard and soft domains cannot be flipped independently. This feature leads to nonuniform costs of write states in terms of latency and energy. However, current SRAM-targeting register allocations do not have a clear understanding of the impact of the different write state-transition costs. As a result, those approaches heuristically select variables to be spilled without considering the spilling priority imposed by MLC STT-RAM. Aiming to address this limitation, this paper proposes a state-transition-aware spilling cost minimization (SSCM policy, to save power when MLC STT-RAM is employed in register design. Specifically, the spilling cost model is first constructed according to the linear combination of different state-transition frequencies. Directed by the proposed cost model, the compiler picks up spilling candidates to achieve lower power and higher performance. Experimental results show that the proposed SSCM technique can save energy by 19.4% and improve the lifetime by 23.2% of MLC STT-RAM-based register design.

Dosimetric impact of systematic MLC positional errors on step and shoot IMRT for prostate cancer: a planning study

International Nuclear Information System (INIS)

Ung, N.M.; Wee, L.; Harper, C.S.

2010-01-01

Full text: The positional accuracy of multi leaf collimators (MLC) is crucial in ensuring precise delivery of intensity-modulated radiotherapy (IMRT). The aim of this planning study was to investigate the dosimetric impact of systematic MLC errors on step and shoot IMRT of prostate cancer. Twelve MLC leaf banks perturbations were introduced to six prostate IMRT treatment plans to simulate MLC systematic errors. Dose volume histograms (OYHs) were generated for the extraction of dose endpoint parameters. Plans were evaluated in terms of changes to the defined endpoint dose parameters, conformity index (CI) and healthy tissue avoidance (HTA) to planning target volume (PTY), rectum and bladder. Negative perturbations of MLC had been found to produce greater changes to endpoint dose parameters than positive perturbations of MLC (p < 0.05). Negative and positive synchronized MLC perturbations of I mm resulted in median changes of -2.32 and 1.78%, respectively to 095% of PTY whereas asynchronized MLC perturbations of the same direction and magnitude resulted in median changes of 1.18 and 0.90%, respectively. Doses to rectum were generally more sensitive to systematic MLC errors compared to bladder. Synchronized MLC perturbations of I mm resulted in median changes of endpoint dose parameters to both rectum and bladder from about I to 3%. Maximum reduction of -4.44 and -7.29% were recorded for CI and HTA, respectively, due to synchronized MLC perturbation of I mm. In summary, MLC errors resulted in measurable amount of dose changes to PTY and surrounding critical structures in prostate LMRT. (author)

Subcortical arteriosclerotic encephalopathy (Binswanger disease)

International Nuclear Information System (INIS)

Settanni, F.; Dumont, P.; Casella, C.L.; Pascuzzi, L.; Cecilio, S.; Caldas, J.G.

1992-01-01

Four patients with variable clinical and tomographic features were diagnosed as having subcortical arteriosclerotic encephalopathy (Binswanger disease). This diagnosis was done based on the presence of subacute progression of focal cerebral deficits, presence of hypertension, systemic vascular disease and dementia. The pathogenesis of subcortical arteriosclerotic encephalopathy is unknown; possible mechanism include diffuse ischemia and fluid transudation with subsequent gliosis related to subacute hypertensive encephalopathy. (author)

TomoTherapy MLC verification using exit detector data

Energy Technology Data Exchange (ETDEWEB)

Chen Quan; Westerly, David; Fang Zhenyu; Sheng, Ke; Chen Yu [TomoTherapy Inc., 1240 Deming Way, Madison, Wisconsin 53717 (United States); Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, Colorado 80045 (United States); Xinghua Cancer Hospital, Xinghua, Jiangsu 225700 (China); Department of Radiation Oncology, University of California-Los Angeles, Los Angeles, California 90095 (United States); TomoTherapy Inc., 1240 Deming Way, Madison, Wisconsin 53717 (United States)

2012-01-15

Purpose: Treatment delivery verification (DV) is important in the field of intensity modulated radiation therapy (IMRT). While IMRT and image guided radiation therapy (IGRT), allow us to create more conformal plans and enables the use of tighter margins, an erroneously executed plan can have detrimental effects on the treatment outcome. The purpose of this study is to develop a DV technique to verify TomoTherapy's multileaf collimator (MLC) using the onboard mega-voltage CT detectors. Methods: The proposed DV method uses temporal changes in the MVCT detector signal to predict actual leaf open times delivered on the treatment machine. Penumbra and scattered radiation effects may produce confounding results when determining leaf open times from the raw detector data. To reduce the impact of the effects, an iterative, Richardson-Lucy (R-L) deconvolution algorithm is applied. Optical sensors installed on each MLC leaf are used to verify the accuracy of the DV technique. The robustness of the DV technique is examined by introducing different attenuation materials in the beam. Additionally, the DV technique has been used to investigate several clinical plans which failed to pass delivery quality assurance (DQA) and was successful in identifying MLC timing discrepancies as the root cause. Results: The leaf open time extracted from the exit detector showed good agreement with the optical sensors under a variety of conditions. Detector-measured leaf open times agreed with optical sensor data to within 0.2 ms, and 99% of the results agreed within 8.5 ms. These results changed little when attenuation was added in the beam. For the clinical plans failing DQA, the dose calculated from reconstructed leaf open times played an instrumental role in discovering the root-cause of the problem. Throughout the retrospective study, it is found that the reconstructed dose always agrees with measured doses to within 1%. Conclusions: The exit detectors in the TomoTherapy treatment

TomoTherapy MLC verification using exit detector data

International Nuclear Information System (INIS)

Chen Quan; Westerly, David; Fang Zhenyu; Sheng, Ke; Chen Yu

2012-01-01

Purpose: Treatment delivery verification (DV) is important in the field of intensity modulated radiation therapy (IMRT). While IMRT and image guided radiation therapy (IGRT), allow us to create more conformal plans and enables the use of tighter margins, an erroneously executed plan can have detrimental effects on the treatment outcome. The purpose of this study is to develop a DV technique to verify TomoTherapy's multileaf collimator (MLC) using the onboard mega-voltage CT detectors. Methods: The proposed DV method uses temporal changes in the MVCT detector signal to predict actual leaf open times delivered on the treatment machine. Penumbra and scattered radiation effects may produce confounding results when determining leaf open times from the raw detector data. To reduce the impact of the effects, an iterative, Richardson-Lucy (R-L) deconvolution algorithm is applied. Optical sensors installed on each MLC leaf are used to verify the accuracy of the DV technique. The robustness of the DV technique is examined by introducing different attenuation materials in the beam. Additionally, the DV technique has been used to investigate several clinical plans which failed to pass delivery quality assurance (DQA) and was successful in identifying MLC timing discrepancies as the root cause. Results: The leaf open time extracted from the exit detector showed good agreement with the optical sensors under a variety of conditions. Detector-measured leaf open times agreed with optical sensor data to within 0.2 ms, and 99% of the results agreed within 8.5 ms. These results changed little when attenuation was added in the beam. For the clinical plans failing DQA, the dose calculated from reconstructed leaf open times played an instrumental role in discovering the root-cause of the problem. Throughout the retrospective study, it is found that the reconstructed dose always agrees with measured doses to within 1%. Conclusions: The exit detectors in the TomoTherapy treatment systems

SU-E-T-195: Gantry Angle Dependency of MLC Leaf Position Error

Energy Technology Data Exchange (ETDEWEB)

Ju, S; Hong, C; Kim, M; Chung, K; Kim, J; Han, Y; Ahn, S; Chung, S; Shin, E; Shin, J; Kim, H; Kim, D; Choi, D [Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

2014-06-01

Purpose: The aim of this study was to investigate the gantry angle dependency of the multileaf collimator (MLC) leaf position error. Methods: An automatic MLC quality assurance system (AutoMLCQA) was developed to evaluate the gantry angle dependency of the MLC leaf position error using an electronic portal imaging device (EPID). To eliminate the EPID position error due to gantry rotation, we designed a reference maker (RM) that could be inserted into the wedge mount. After setting up the EPID, a reference image was taken of the RM using an open field. Next, an EPID-based picket-fence test (PFT) was performed without the RM. These procedures were repeated at every 45° intervals of the gantry angle. A total of eight reference images and PFT image sets were analyzed using in-house software. The average MLC leaf position error was calculated at five pickets (-10, -5, 0, 5, and 10 cm) in accordance with general PFT guidelines using in-house software. This test was carried out for four linear accelerators. Results: The average MLC leaf position errors were within the set criterion of <1 mm (actual errors ranged from -0.7 to 0.8 mm) for all gantry angles, but significant gantry angle dependency was observed in all machines. The error was smaller at a gantry angle of 0° but increased toward the positive direction with gantry angle increments in the clockwise direction. The error reached a maximum value at a gantry angle of 90° and then gradually decreased until 180°. In the counter-clockwise rotation of the gantry, the same pattern of error was observed but the error increased in the negative direction. Conclusion: The AutoMLCQA system was useful to evaluate the MLC leaf position error for various gantry angles without the EPID position error. The Gantry angle dependency should be considered during MLC leaf position error analysis.

Dosimetric impact of systematic MLC positional errors on step and shoot IMRT for prostate cancer: a planning study

International Nuclear Information System (INIS)

Ung, N.M.; Harper, C.S.; Wee, L.

2011-01-01

Full text: The positional accuracy of multileaf collimators (MLC) is crucial in ensuring precise delivery of intensity-modulated radiotherapy (IMRT). The aim of this planning study was to investigate the dosimetric impact of systematic MLC positional errors on step and shoot IMRT of prostate cancer. A total of 12 perturbations of MLC leaf banks were introduced to six prostate IMRT treatment plans to simulate MLC systematic positional errors. Dose volume histograms (DVHs) were generated for the extraction of dose endpoint parameters. Plans were evaluated in terms of changes to the defined endpoint dose parameters, conformity index (CI) and healthy tissue avoidance (HTA) to planning target volume (PTV), rectum and bladder. Negative perturbations of MLC had been found to produce greater changes to endpoint dose parameters than positive perturbations of MLC (p 9 5 of -1.2 and 0.9% respectively. Negative and positive synchronised MLC perturbations of I mm in one direction resulted in median changes in D 9 5 of -2.3 and 1.8% respectively. Doses to rectum were generally more sensitive to systematic MLC en-ors compared to bladder (p < 0.01). Negative and positive synchronised MLC perturbations of I mm in one direction resulted in median changes in endpoint dose parameters of rectum and bladder from 1.0 to 2.5%. Maximum reduction of -4.4 and -7.3% were recorded for conformity index (CI) and healthy tissue avoidance (HT A) respectively due to synchronised MLC perturbation of 1 mm. MLC errors resulted in dosimetric changes in IMRT plans for prostate. (author)

Evaluation of two methods of predicting MLC leaf positions using EPID measurements

International Nuclear Information System (INIS)

Parent, Laure; Seco, Joao; Evans, Phil M.; Dance, David R.; Fielding, Andrew

2006-01-01

In intensity modulated radiation treatments (IMRT), the position of the field edges and the modulation within the beam are often achieved with a multileaf collimator (MLC). During the MLC calibration process, due to the finite accuracy of leaf position measurements, a systematic error may be introduced to leaf positions. Thereafter leaf positions of the MLC depend on the systematic error introduced on each leaf during MLC calibration and on the accuracy of the leaf position control system (random errors). This study presents and evaluates two methods to predict the systematic errors on the leaf positions introduced during the MLC calibration. The two presented methods are based on a series of electronic portal imaging device (EPID) measurements. A comparison with film measurements showed that the EPID could be used to measure leaf positions without introducing any bias. The first method, referred to as the 'central leaf method', is based on the method currently used at this center for MLC leaf calibration. It mimics the manner in which leaf calibration parameters are specified in the MLC control system and consequently is also used by other centers. The second method, a new method proposed by the authors and referred to as the ''individual leaf method,'' involves the measurement of two positions for each leaf (-5 and +15 cm) and the interpolation and extrapolation from these two points to any other given position. The central leaf method and the individual leaf method predicted leaf positions at prescribed positions of -11, 0, 5, and 10 cm within 2.3 and 1.0 mm, respectively, with a standard deviation (SD) of 0.3 and 0.2 mm, respectively. The individual leaf method provided a better prediction of the leaf positions than the central leaf method. Reproducibility tests for leaf positions of -5 and +15 cm were performed. The reproducibility was within 0.4 mm on the same day and 0.4 mm six weeks later (1 SD). Measurements at gantry angles of 0 deg., 90 deg., and 270 deg

Subcortical Brain Morphology in Schizophrenia : Descriptive analysis based on MRI findings of subcortical brain volumes

OpenAIRE

Gunleiksrud, Sindre

2009-01-01

The aim of this study was to investigate magnetic resonance images (MR) from patients with schizophrenia and healthy control subjects for difference in brain morphology with focus on subcortical brain volumes. Method: The study compared fourteen subcortical brain structure volumes of 96 patients diagnosed with schizophrenia (n=81) or schizoaffective disorder (n=15) with 106 healthy control subjects. Volume measures were obtained using voxel-based morphometry (FreeSurfer software suite) of ...

Inflammatory dentigerous cyst mimicking a periapical cyst

Directory of Open Access Journals (Sweden)

Priya Gupta

2016-01-01

Full Text Available Odontogenic cysts are the most common form of cystic lesions that affect the maxillofacial region. The low frequency of dentigerous cysts in children has been reported in dental literature. Dentigerous cysts arise as a result of cystic change in the remains of the enamel organ after the process of enamel formation is complete. They enclose the crown of an unerupted tooth and are attached to the cementoenamel junction. Although most dentigerous cysts are considered developmental cysts, some cases seem to have an inflammatory origin. The purpose of this report is to present a case of an 8-year-old male patient with a dentigerous cyst of inflammatory origin.

Radiological diagnosis of periventricular and subcortical leukomalacia

Energy Technology Data Exchange (ETDEWEB)

Taboada, D.; Alonso, A.; Olague, R.; Mulas, F.; Andres, V.

1980-08-01

Nine newborn infants with histories of perinatal asphyxia are presented. The pneumoencephalographic findings which led to the diagnosis are typical and constant. They include marked subcortical atrophy with rounded, dilated, and undisplaced lateral ventricles. Cystography with 3 cc of air demonstrated multiple subcortical and paraventricular cavities, without communication with the ventricular system, but with the typical honeycomb appearance of paraventricular and subcortical leukomalacia described in postmortem findings. The CT findings are typical, and provide the location of the cavities as well as their density.

Motion management during IMAT treatment of mobile lung tumors-A comparison of MLC tracking and gated delivery

DEFF Research Database (Denmark)

Falk, Marianne; Pommer, Tobias; Keall, Paul

2014-01-01

Purpose:To compare real-time dynamic multileaf collimator (MLC) tracking, respiratory amplitude and phase gating, and no compensation for intrafraction motion management during intensity modulated arc therapy (IMAT). Methods: Motion management with MLC tracking and gating was evaluated for four...... tracking reduced the effects of the target movements, although the gated delivery showed a better dosimetric accuracy and enabled a larger reduction of the margins in some cases. MLC tracking did not prolong the treatment time compared to delivery with no motion compensation while gating had a considerably...... of the dosimetric error contributions showed that the gated delivery mainly had errors in target localization, while MLC tracking also had contributions from MLC leaf fitting and leaf adjustment. The average treatment time was about three times longer with gating compared to delivery with MLC tracking (that did...

SU-E-T-646: Quality Assurance of Truebeam Multi-Leaf Collimator Using a MLC QA Phantom

International Nuclear Information System (INIS)

Zhang, J; Lu, J; Hong, D

2015-01-01

Purpose: To perform a routine quality assurance procedure for Truebeam multi-leaf collimator (MLC) using MLC QA phantom, verify the stability and reliability of MLC during the treatment. Methods: MLC QA phantom is a specialized phantom for MLC quality assurance (QA), and contains five radio-opaque spheres that are embedded in an “L” shape. The phantom was placed isocentrically on the Truebeam treatment couch for the tests. A quality assurance plan was setted up in the Eclipse v10.0, the fields that need to be delivered in order to acquire the necessary images, the MLC shapes can then be obtained by the images. The images acquired by the electronic portal imaging device (EPID), and imported into the PIPSpro software for the analysis. The tests were delivered twelve weeks (once a week) to verify consistency of the delivery, and the images are acquired in the same manner each time. Results: For the Leaf position test, the average position error was 0.23mm±0.02mm (range: 0.18mm∼0.25mm). The Leaf width was measured at the isocenter, the average error was 0.06mm±0.02mm (range: 0.02mm∼0.08mm) for the Leaf width test. Multi-Port test showed the dynamic leaf shift error, the average error was 0.28mm±0.03mm (range: 0.2mm∼0.35mm). For the leaf transmission test, the average inter-leaf leakage value was 1.0%±0.17% (range: 0.8%∼1.3%) and the average inter-bank leakage value was 32.6%±2.1% (range: 30.2%∼36.1%). Conclusion: By the test of 12 weeks, the MLC system of the Truebeam is running in a good condition and the MLC system can be steadily and reliably carried out during the treatment. The MLC QA phantom is a useful test tool for the MLC QA

Orthokeratinised odontogenic cyst mimicking periapical cyst.

Science.gov (United States)

Rajalakshmi, R; Sreeja, C; Vijayalakshmi, D; Leelarani, V

2013-10-07

Orthokeratinised odontogenic cyst (OOC) denotes the odontogenic cyst that microscopically has an orthokeratinised epithelial lining. OOC is characterised by a less-aggressive behaviour and a low rate of recurrence. This report describes a case of OOC involving posterior part of the mandible that mimicked periapical cyst in a 14-year-old boy. The initial clinical diagnosis was given as periapical cyst based on the clinical and radiographical features. Enucleation of the cyst was performed and the specimen was sent for histopathological examination. A definite diagnosis of OOC was made by histopathological examination of the biopsy specimen. This case emphases on including OOC in the differential diagnosis of radiolucencies occurring in the periapical region of non-vital tooth.

Generation of cytotoxic T lymphocytes in vitro. VII. Suppressive effect of irradiated MLC cells on CTL response

International Nuclear Information System (INIS)

Fitch, F.W.; Engers, H.D.; Cerottini, J.C.; Bruner, K.T.

1976-01-01

Irradiated cells obtained from MLC at the peak of the CTL response caused profound suppression of generation of CTL when added in small numbers at the initiation of primary MLC prepared with normal spleen cells. The inhibitory activity of the MLC cells was not affected by irradiation (1000 rads) but was abolished by treatment with anti-theta serum and complement. The suppression was immunologically specific. The response of A (H-2/sup a/) spleen cells toward C3H (H-2/sup k/) alloantigens was suppressed by irradiated MLC cells obtained from MLC prepared with A spleen cells and irradiated C3H-stimulating cells, whereas the response of A spleen cells toward DBA/2 (H-2/sup d/) alloantigens was affected relatively little. However, if irradiated C3H x DBA/2F1 hybrid spleen cells were used to stimulate A spleen cells in MLC, addition of irradiated MLC cells having cytotoxic activity toward C3H antigens abolished the response to both C3H and DBA/2 antigens. The response to DBA/2 antigens was much less affected when a mixture of irradiated C3H and DBA/2 spleen cells was used as stimulating cells. Thus, the presence of MLC cells having cytotoxic activity toward one alloantigen abolished the response to another non-cross-reacting antigen only when both antigens were present on the same F1 hybrid-stimulating cells. This suppression of generation of CTL by irradiated MLC cells apparently involves inactivation of alloantigen-bearing stimulating cells as a result of residual cytotoxic activity of the irradiated MLC cells. This mechanism may be active during the decline in CTL activity noted in the normal immune response in vivo and in vitro

Simple bone cyst of mandible mimicking periapical cyst.

Science.gov (United States)

Hs, Charan Babu; Rai, Bhagawan Das; Nair, Manju A; Astekar, Madhusudan S

2012-05-29

Simple bone cysts (SBC) are pseudocysts occurring less commonly in the maxillofacial region. The uncertain and unclear etiopathogenesis led to numerous synonyms to refer this particular cyst. These cysts are devoid of an epithelial lining and are usually empty or contain blood or straw-colored fluid. In jaws initially it mimics a periapical cyst and later can lead to cortical bone expansion warranting for radical approach, which is seldom required. SBC is predominantly diagnosed in first two decades of life. Here we report a case of solitary bone cyst mimicking a periapical cyst of a mandibular molar in a 37-year-old patient.

6 MV dosimetric characterization of the 160 MLC, the new Siemens multileaf collimator

International Nuclear Information System (INIS)

Tacke, Martin B.; Nill, Simeon; Haering, Peter; Oelfke, Uwe

2008-01-01

New technical developments constantly aim at improving the outcome of radiation therapy. With the use of a computer-controlled multileaf collimator (MLC), the quality of the treatment and the efficiency in patient throughput is significantly increased. New MLC designs aim to further enhance the advantages. In this article, we present the first detailed experimental investigation of the new 160 MLC TM , Siemens Medical Solutions. The assessment included the experimental investigation of typical MLC characteristics such as leakage, tongue-and-groove effect, penumbra, leaf speed, and leaf positioning accuracy with a 6 MV treatment beam. The leakage is remarkably low with an average of 0.37% due to a new design principle of slightly tilted leaves instead of the common tongue-and-groove design. But due to the tilt, the triangular tongue-and-groove effect occurs. Its magnitude of approximately 19% is similar to the dose defect measured for MLCs with the common tongue-and-groove design. The average longitudinal penumbra measured at depth d max =15 mm with standard 100x100 mm 2 fields is 4.1±0.5 mm for the central range and increases to 4.9±1.3 mm for the entire field range of 400x400 mm 2 . The increase is partly due to the single-focusing design and the large distance between the MLC and the isocenter enabling a large patient clearance. Regarding the leaf speed, different velocity tests were performed. The positions of the moving leaves were continuously recorded with the kilovoltage-imaging panel. The maximum leaf velocities measured were 42.9±0.6 mm/s. In addition, several typical intensity-modulated radiation therapy treatments were performed and the delivery times compared to the Siemens OPTIFOCUS MLC. An average decrease of 11% in delivery time was observed. The experimental results presented in this article indicate that the dosimetric characteristics of the 160 MLC are capable of improving the quality of dose delivery with respect to precision and dose

Simple bone cyst of mandible mimicking periapical cyst

Directory of Open Access Journals (Sweden)

Charan Babu HS

2012-05-01

Full Text Available Simple bone cysts (SBC are pseudocysts occurring less commonly in the maxillofacial region. The uncertain and unclear etiopathogenesis led to numerous synonyms to refer this particular cyst. These cysts are devoid of an epithelial lining and are usually empty or contain blood or straw-colored fluid. In jaws initially it mimics a periapical cyst and later can lead to cortical bone expansion warranting for radical approach, which is seldom required. SBC is predominantly diagnosed in first two decades of life. Here we report a case of solitary bone cyst mimicking a periapical cyst of a mandibular molar in a 37-year-old patient.

Subcortical functional reorganization due to early blindness.

Science.gov (United States)

Coullon, Gaelle S L; Jiang, Fang; Fine, Ione; Watkins, Kate E; Bridge, Holly

2015-04-01

Lack of visual input early in life results in occipital cortical responses to auditory and tactile stimuli. However, it remains unclear whether cross-modal plasticity also occurs in subcortical pathways. With the use of functional magnetic resonance imaging, auditory responses were compared across individuals with congenital anophthalmia (absence of eyes), those with early onset (in the first few years of life) blindness, and normally sighted individuals. We find that the superior colliculus, a "visual" subcortical structure, is recruited by the auditory system in congenital and early onset blindness. Additionally, auditory subcortical responses to monaural stimuli were altered as a result of blindness. Specifically, responses in the auditory thalamus were equally strong to contralateral and ipsilateral stimulation in both groups of blind subjects, whereas sighted controls showed stronger responses to contralateral stimulation. These findings suggest that early blindness results in substantial reorganization of subcortical auditory responses. Copyright © 2015 the American Physiological Society.

SU-F-T-650: The Comparison of Robotic Partial Breast Stereotactic Irradiation Using MLC Vs. Iris Cone

Energy Technology Data Exchange (ETDEWEB)

Ding, C; Timmerman, R; Jiang, S; Rahimi, A [UT Southwestern Medical Center, Dallas, TX (United States)

2016-06-15

Purpose: To evaluate the dosimetric impact on treatment planning for partial breast stereotactic irradiation using Cyberknife with MLC versus Iris Cone. Methods: Ten patients whom underwent lumpectomy for DCIS or stage I invasive non-lobular epithelial breast cancer were included in this study. All patients were previously treated on the Cyberknife using Iris cone with the prescription dose of 37.5Gy in 5 fractions covering at least 95% of PTV on our phase I SBRT 5 fraction partial breast irradiation trial. Retrospectively, treatment planning was performed and compared using the new Cyberknife M6 MLC system for each patient. Using the same contours and critical organ constraints for both MLC and Iris cone plans, the dose on target and critical organs were analyzed accordingly. Results: Dose to critical organs such as ipsilateral lung, contralateral lung, heart, skin, ipsilateral breast, and rib were analyzed, as well as conformity index and high dose spillage of the target area. In 9 of 10 patients, the MLC plans had less total ipsilateral breast volume encompassing the 50% prescription isodose (mean:22.3±8.2% MLC vs. 31.6±8.0 Iris, p=0.00014) .The MLC plans mean estimated treatment delivery time was significantly less than the Iris plans (51±3.9min vs. 56.2±9min, p=0.03) Both MLC and Iris cone plans were able to meet all dose constraints and there was no statistical difference between those dose constraints. Conclusion: Both MLC and Iris Cone can deliver conformal dose to a partial breast target and satisfy the dose constraints of critical organs. The new Cyberknife with MLC can deliver a more conformal dose in the lower dose region and spare more ipsilateral breast tissue to the 50% prescription isodose. The treatment time for partial breast SBRT plans was also reduced using MLC. Project receives research support from Accuray Inc.

First evaluation of the feasibility of MLC tracking using ultrasound motion estimation

Energy Technology Data Exchange (ETDEWEB)

Fast, Martin F., E-mail: martin.fast@icr.ac.uk; O’Shea, Tuathan P., E-mail: tuathan.oshea@nhs.net; Nill, Simeon; Oelfke, Uwe; Harris, Emma J. [Joint Department of Physics, The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London SM2 5NG (United Kingdom)

2016-08-15

Purpose: To quantify the performance of the Clarity ultrasound (US) imaging system (Elekta AB, Stockholm, Sweden) for real-time dynamic multileaf collimator (MLC) tracking. Methods: The Clarity calibration and quality assurance phantom was mounted on a motion platform moving with a periodic sine wave trajectory. The detected position of a 30 mm hypoechogenic sphere within the phantom was continuously reported via Clarity’s real-time streaming interface to an in-house tracking and delivery software and subsequently used to adapt the MLC aperture. A portal imager measured MV treatment field/MLC apertures and motion platform positions throughout each experiment to independently quantify system latency and geometric error. Based on the measured range of latency values, a prostate stereotactic body radiation therapy (SBRT) delivery was performed with three realistic motion trajectories. The dosimetric impact of system latency on MLC tracking was directly measured using a 3D dosimeter mounted on the motion platform. Results: For 2D US imaging, the overall system latency, including all delay times from the imaging and delivery chain, ranged from 392 to 424 ms depending on the lateral sector size. For 3D US imaging, the latency ranged from 566 to 1031 ms depending on the elevational sweep. The latency-corrected geometric root-mean squared error was below 0.75 mm (2D US) and below 1.75 mm (3D US). For the prostate SBRT delivery, the impact of a range of system latencies (400–1000 ms) on the MLC tracking performance was minimal in terms of gamma failure rate. Conclusions: Real-time MLC tracking based on a noninvasive US input is technologically feasible. Current system latencies are higher than those for x-ray imaging systems, but US can provide full volumetric image data and the impact of system latency was measured to be small for a prostate SBRT case when using a US-like motion input.

Brushed permanent magnet DC MLC motor operation in an external magnetic field.

Science.gov (United States)

Yun, J; St Aubin, J; Rathee, S; Fallone, B G

2010-05-01

Linac-MR systems for real-time image-guided radiotherapy will utilize the multileaf collimators (MLCs) to perform conformal radiotherapy and tumor tracking. The MLCs would be exposed to the external fringe magnetic fields of the linac-MR hybrid systems. Therefore, an experimental investigation of the effect of an external magnetic field on the brushed permanent magnet DC motors used in some MLC systems was performed. The changes in motor speed and current were measured for varying external magnetic field strengths up to 2000 G generated by an EEV electromagnet. These changes in motor characteristics were measured for three orientations of the motor in the external magnetic field, mimicking changes in motor orientations due to installation and/or collimator rotations. In addition, the functionality of the associated magnetic motor encoder was tested. The tested motors are used with the Varian 120 leaf Millennium MLC (Maxon Motor half leaf and full leaf motors) and the Varian 52 leaf MKII MLC (MicroMo Electronics leaf motor) including a carriage motor (MicroMo Electronics). In most cases, the magnetic encoder of the motors failed prior to any damage to the gearbox or the permanent magnet motor itself. This sets an upper limit of the external magnetic field strength on the motor function. The measured limits of the external magnetic fields were found to vary by the motor type. The leaf motor used with a Varian 52 leaf MKII MLC system tolerated up to 450 +/- 10 G. The carriage motor tolerated up to 2000 +/- 10 G field. The motors used with the Varian 120 leaf Millennium MLC system were found to tolerate a maximum of 600 +/- 10 G. The current Varian MLC system motors can be used for real-time image-guided radiotherapy coupled to a linac-MR system, provided the fringe magnetic fields at their locations are below the determined tolerance levels. With the fringe magnetic fields of linac-MR systems expected to be larger than the tolerance levels determined, some form of

Brushed permanent magnet DC MLC motor operation in an external magnetic field

Energy Technology Data Exchange (ETDEWEB)

Yun, J.; St Aubin, J.; Rathee, S.; Fallone, B. G. [Department of Physics, University of Alberta, 11322-89 Avenue, Edmonton, Alberta T6G 2G7 (Canada) and Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada) and Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Department of Physics, University of Alberta, 11322-89 Avenue, Edmonton, Alberta T6G 2G7 (Canada); Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada) and Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada)

2010-05-15

Purpose: Linac-MR systems for real-time image-guided radiotherapy will utilize the multileaf collimators (MLCs) to perform conformal radiotherapy and tumor tracking. The MLCs would be exposed to the external fringe magnetic fields of the linac-MR hybrid systems. Therefore, an experimental investigation of the effect of an external magnetic field on the brushed permanent magnet DC motors used in some MLC systems was performed. Methods: The changes in motor speed and current were measured for varying external magnetic field strengths up to 2000 G generated by an EEV electromagnet. These changes in motor characteristics were measured for three orientations of the motor in the external magnetic field, mimicking changes in motor orientations due to installation and/or collimator rotations. In addition, the functionality of the associated magnetic motor encoder was tested. The tested motors are used with the Varian 120 leaf Millennium MLC (Maxon Motor half leaf and full leaf motors) and the Varian 52 leaf MKII MLC (MicroMo Electronics leaf motor) including a carriage motor (MicroMo Electronics). Results: In most cases, the magnetic encoder of the motors failed prior to any damage to the gearbox or the permanent magnet motor itself. This sets an upper limit of the external magnetic field strength on the motor function. The measured limits of the external magnetic fields were found to vary by the motor type. The leaf motor used with a Varian 52 leaf MKII MLC system tolerated up to 450{+-}10 G. The carriage motor tolerated up to 2000{+-}10 G field. The motors used with the Varian 120 leaf Millennium MLC system were found to tolerate a maximum of 600{+-}10 G. Conclusions: The current Varian MLC system motors can be used for real-time image-guided radiotherapy coupled to a linac-MR system, provided the fringe magnetic fields at their locations are below the determined tolerance levels. With the fringe magnetic fields of linac-MR systems expected to be larger than the

Brushed permanent magnet DC MLC motor operation in an external magnetic field

International Nuclear Information System (INIS)

Yun, J.; St Aubin, J.; Rathee, S.; Fallone, B. G.

2010-01-01

Purpose: Linac-MR systems for real-time image-guided radiotherapy will utilize the multileaf collimators (MLCs) to perform conformal radiotherapy and tumor tracking. The MLCs would be exposed to the external fringe magnetic fields of the linac-MR hybrid systems. Therefore, an experimental investigation of the effect of an external magnetic field on the brushed permanent magnet DC motors used in some MLC systems was performed. Methods: The changes in motor speed and current were measured for varying external magnetic field strengths up to 2000 G generated by an EEV electromagnet. These changes in motor characteristics were measured for three orientations of the motor in the external magnetic field, mimicking changes in motor orientations due to installation and/or collimator rotations. In addition, the functionality of the associated magnetic motor encoder was tested. The tested motors are used with the Varian 120 leaf Millennium MLC (Maxon Motor half leaf and full leaf motors) and the Varian 52 leaf MKII MLC (MicroMo Electronics leaf motor) including a carriage motor (MicroMo Electronics). Results: In most cases, the magnetic encoder of the motors failed prior to any damage to the gearbox or the permanent magnet motor itself. This sets an upper limit of the external magnetic field strength on the motor function. The measured limits of the external magnetic fields were found to vary by the motor type. The leaf motor used with a Varian 52 leaf MKII MLC system tolerated up to 450±10 G. The carriage motor tolerated up to 2000±10 G field. The motors used with the Varian 120 leaf Millennium MLC system were found to tolerate a maximum of 600±10 G. Conclusions: The current Varian MLC system motors can be used for real-time image-guided radiotherapy coupled to a linac-MR system, provided the fringe magnetic fields at their locations are below the determined tolerance levels. With the fringe magnetic fields of linac-MR systems expected to be larger than the tolerance

First evaluation of the feasibility of MLC tracking using ultrasound motion estimation

International Nuclear Information System (INIS)

Fast, Martin F.; O’Shea, Tuathan P.; Nill, Simeon; Oelfke, Uwe; Harris, Emma J.

2016-01-01

Purpose: To quantify the performance of the Clarity ultrasound (US) imaging system (Elekta AB, Stockholm, Sweden) for real-time dynamic multileaf collimator (MLC) tracking. Methods: The Clarity calibration and quality assurance phantom was mounted on a motion platform moving with a periodic sine wave trajectory. The detected position of a 30 mm hypoechogenic sphere within the phantom was continuously reported via Clarity’s real-time streaming interface to an in-house tracking and delivery software and subsequently used to adapt the MLC aperture. A portal imager measured MV treatment field/MLC apertures and motion platform positions throughout each experiment to independently quantify system latency and geometric error. Based on the measured range of latency values, a prostate stereotactic body radiation therapy (SBRT) delivery was performed with three realistic motion trajectories. The dosimetric impact of system latency on MLC tracking was directly measured using a 3D dosimeter mounted on the motion platform. Results: For 2D US imaging, the overall system latency, including all delay times from the imaging and delivery chain, ranged from 392 to 424 ms depending on the lateral sector size. For 3D US imaging, the latency ranged from 566 to 1031 ms depending on the elevational sweep. The latency-corrected geometric root-mean squared error was below 0.75 mm (2D US) and below 1.75 mm (3D US). For the prostate SBRT delivery, the impact of a range of system latencies (400–1000 ms) on the MLC tracking performance was minimal in terms of gamma failure rate. Conclusions: Real-time MLC tracking based on a noninvasive US input is technologically feasible. Current system latencies are higher than those for x-ray imaging systems, but US can provide full volumetric image data and the impact of system latency was measured to be small for a prostate SBRT case when using a US-like motion input.

Comparison of two methods for quantifying the accuracy of the positioning of the blades of the MLC

International Nuclear Information System (INIS)

Garcia Yip, Fernando; Silvestre Patallo, Ileana; Diaz Moreno, Rogelio

2009-01-01

Conformal radiotherapy treatment (3DCRT) and intensity modulated (IMRT) require more accurate positioning of the blades collimator. The procedure Stanford Quality Control (QC) is based MLC determine the possibility of small errors in positioning (<1mm) to from the variation that occurs in the relative response of a small detector depending on the irradiated fraction of its volume. The aim of this work was to establish a methodology to characterize quantitatively individual displacements of each layer, taking into account the tolerances established for 3DCRT and IMRT are ± 1mm. We determined the accuracy of the positioning of the throttle blades MLC Elekta Precise linear (S/N1220) of INOR. The MLC has 40 pairs of sheets tungsten 1 cm wide at the isocenter. The lower jaws of the collimator side is backed by the MLC. We compare two variants Stanford technique, one, using as detector portal imaging system Electronics (EPID) and the other using the two-dimensional camera system ionization 2D array (PTW 729). We used analysis tools programmed in MatLab image and application to MLC Checker processing the signals of the 2D array. We established the reference values of the relative response of detectors employees (EPID and 2D array) for the 40 pairs of blades to MLC and positions of both banks from 13cm-13cm and up to 1cm intervals. It implemented a procedure for the routine application of this test in MLC monthly checks. Procedure was applied as part of systematic quality control of MLC and found the mean error of positioning of each blade from the implementation of the QC procedure and to carry out this work. It was verified that the linac MLC 1220 of INOR meets tolerances established for the delivery of advanced treatment techniques 3D conformal radiotherapy and IMRT. (author)

Implementation and acceptance of dynamic MLC for IMRT and VMAT

International Nuclear Information System (INIS)

Garcia, B.; Marquina, J.; Ramirez, J.; Gonzales, A.

2014-08-01

The use of Multi-leaf Collimator (MLC) in Intensity-Modulated Radiation Therapy (IMRT) for dynamic treatment techniques as Volumetric Modulated Arc Therapy (VMAT) makes that the movement controls as the speed of the MLC are quantified by means of an acceptance test. The objective determination of the operation regulations of the radiotherapy equipment requires ideally the establishment of the quantitative relationship among the performance deviations and clinical results or some acceptable substitute. Different protocols exist detailed with parameters and acceptance ranges according to the MLC thickness. In our case the acceptance test was carried out for 120-MLC of Trilogy equipment brand Varian. For all the test were used 300-200 Um for each formed beam lets; source-surface distance (SSD) of 100 cm. 9 acceptance tests were used each one with different purposes like to quantify, synchronization, stability, complexity, precision, positioning, conformity, dynamic movements for the case of dynamic wedges, consecutive moves, among others, for the measurements were used film badges dosimetry (Gafchromic Ebt-3 scanner Epson expression 10000 XL); additionally the results were compared with a diodes arrangement Map-Check 2 brand Sun Nuclear; that consists of 1527 diodes prepared in a field of 32 x 26 cm located at a distance of 1 cm parallel, 0.5 cm diagonally. All the developed tests were inside the acceptance tolerance parameters when comparing the obtained result regarding the badges and the Map-Check was found a discrepancy of 0.01%, what gives a treatment certainty to the moment to impart volumetric dose in dynamic fields to the patients. (Author)

TH-AB-202-02: Real-Time Verification and Error Detection for MLC Tracking Deliveries Using An Electronic Portal Imaging Device

International Nuclear Information System (INIS)

J Zwan, B; Colvill, E; Booth, J; J O’Connor, D; Keall, P; B Greer, P

2016-01-01

Purpose: The added complexity of the real-time adaptive multi-leaf collimator (MLC) tracking increases the likelihood of undetected MLC delivery errors. In this work we develop and test a system for real-time delivery verification and error detection for MLC tracking radiotherapy using an electronic portal imaging device (EPID). Methods: The delivery verification system relies on acquisition and real-time analysis of transit EPID image frames acquired at 8.41 fps. In-house software was developed to extract the MLC positions from each image frame. Three comparison metrics were used to verify the MLC positions in real-time: (1) field size, (2) field location and, (3) field shape. The delivery verification system was tested for 8 VMAT MLC tracking deliveries (4 prostate and 4 lung) where real patient target motion was reproduced using a Hexamotion motion stage and a Calypso system. Sensitivity and detection delay was quantified for various types of MLC and system errors. Results: For both the prostate and lung test deliveries the MLC-defined field size was measured with an accuracy of 1.25 cm 2 (1 SD). The field location was measured with an accuracy of 0.6 mm and 0.8 mm (1 SD) for lung and prostate respectively. Field location errors (i.e. tracking in wrong direction) with a magnitude of 3 mm were detected within 0.4 s of occurrence in the X direction and 0.8 s in the Y direction. Systematic MLC gap errors were detected as small as 3 mm. The method was not found to be sensitive to random MLC errors and individual MLC calibration errors up to 5 mm. Conclusion: EPID imaging may be used for independent real-time verification of MLC trajectories during MLC tracking deliveries. Thresholds have been determined for error detection and the system has been shown to be sensitive to a range of delivery errors.

A multi-institution evaluation of MLC log files and performance in IMRT delivery

International Nuclear Information System (INIS)

Kerns, James R; Childress, Nathan; Kry, Stephen F

2014-01-01

The multileaf collimator (MLC) is a critical component to accurate intensity-modulated radiotherapy (IMRT) delivery. This study examined MLC positional accuracy via MLC logs from Varian machines from six institutions and three delivery techniques to evaluate typical positional accuracy and treatment and mechanical parameters that affect accuracy. Typical accuracy achieved was compared against TG-142 recommendations for MLC performance; more appropriate recommendations are suggested. Over 85,000 Varian MLC treatment logs were collected from six institutions and analyzed with FractionCHECK. Data were binned according to institution and treatment type to determine overall root mean square (RMS) and 95 th percentile error values, and then to look for correlations between those errors and with mechanical and treatment parameters including mean and maximum leaf speed, gantry angle, beam-on time, mean leaf error, and number of segments. Results of treatment logs found that leaf RMS error and 95 th percentile leaf error were consistent between institutions, but varied by treatment type. The step and shoot technique had very small errors: the mean RMS leaf error was 0.008 mm. For dynamic treatments the mean RMS leaf error was 0.32 mm, while volumetric-modulated arc treatment (VMAT) showed an RMS leaf error of 0.46 mm. Most MLC leaf errors were found to be well below TG-142 recommended tolerances. For the dynamic and VMAT techniques, the mean and maximum leaf speeds were significantly linked to the leaf RMS error. Additionally, for dynamic delivery, the mean leaf error was correlated with RMS error, whereas for VMAT the average gantry speed was correlated. For all treatments, the RMS error and the 95 th percentile leaf error were correlated. Restricting the maximum leaf speed can help improve MLC performance for dynamic and VMAT deliveries. Furthermore, the tolerances of leaf RMS and error counts for all treatment types should be tightened from the TG-142 values to make them

Independent dose calculation of the Tps Iplan in radiotherapy conformed with MLC; Calculo independiente de dosis del TPS Iplan en radioterapia conformada con MLC

Energy Technology Data Exchange (ETDEWEB)

Adrada, A.; Tello, Z.; Medina, L.; Garrigo, E.; Venencia, D., E-mail: jorge.alberto.adrada@gmail.com [Instituto Privado de Radioterapia, Obispo Oro 423, X5000BFI Cordoba (Argentina)

2014-08-15

The systems utilization of independent dose calculation in three dimensional-Conformal Radiation Therapy (3D-Crt) treatments allows a direct verification of the treatments times. The utilization of these systems allows diminishing the probability of errors occurrence generated by the treatment planning system (Tps), allowing a detailed analysis of the dose to delivering and review of the normalization point (Np) or prescription. The independent dose calculation is realized across the knowledge of dosimetric parameters of the treatment machine and particular characteristics of every individual field. The aim of this work is develops a calculation system of punctual doses for isocentric fields conformed with multi-leaf collimation systems (MLC), where the dose calculation is in conformity with the suggested ones by ICRU Report No. 42, 1987. Calculation software was realized in C ++ under a free platform of programming (Code::Blocks). The system uses files in format Rtp, exported from the Tps to systems of record and verification (Lantis). This file contains detailed information of the dose, Um, position of the MLC sheets and collimators for every field of treatment. The size of equivalent field is obtained from the positions of every sheet; the effective depth of calculation can be introduced from the dosimetric report of the Tps or automatically from the DFS of the field. The 3D coordinates of the isocenter and the Np for the treatment plan must be introduced manually. From this information the system looks the dosimetric parameters and calculates the Um. The calculations were realized in two accelerators a NOVALIS Tx (Varian) with 120 sheets of high definition (hd-MLC) and a PRIMUS Optifocus (Siemens) with 82 sheets. 705 patients were analyzed for a total of 1082, in plans made for both equipment s, the average uncertainty with regard to the calculation of the Tps is-0.43% ± 2.42% in a range between [-7.90 %, 7.50 %]. The major uncertainty was in Np near of the

A method for testing the performance and the accuracy of the binary MLC used in helical tomotherapy

Energy Technology Data Exchange (ETDEWEB)

Lissner, Steffen; Schubert, Kai; Klueter, Sebastian; Oetzel, Dieter; Debus, Juergen [University Hospital Heidelberg (Germany). Dept. of Radiation Oncology

2013-08-01

During a helical tomotherapy a binary MLC is used for fluence modulation. The 64 pneumatically driven leaves of the MLC are either completely open or closed. Th e fast and frequent leaf movements result in a high demand of accuracy and stability of the MLC. This article is based on the analytical investigation of the accuracy and the stability of the MLC. Different patterns of MLC movements were generated to investigate the characteristics of the MLC. One of the considered aspects contains the friction between the leaves. The influence of variations of the compressed air on the MLC was also explored. The integrated MVCT detector of the tomotherapy system deposits the treatment data in a matrix. The detector is triggered with the linear accelerator, which is pulsed by 300Hz. The data matrix is available after the treatment. An IDL (Interactive Data Language) routine was programmed in order to analyse the matrix. The points of time, at which the leaves open (POT), and the period, in which the leaves stay open (LOT), were measured and compared with the desired values. That procedure has been repeated several times a week for approximately 6 months to investigate the stability of the MLC. Relative deviations of the LOT from -0.4% to -5.4% were measured. The friction between the leaves had no significant influence on the LOT. The available compressed air, that is used to move the leaves, depends on the number of moving leaves and also on the previous movements of the MLC. Variations of the compressed air resulted in deviations of the LOT from -1.8% to -3.7%. The measured POT deviates from the programmed POT up to -18.4ms {+-} 0.7ms. This maximal deviation correlates with a shift of the gantry angle of 0.52 which is negligible. The MLC has shown a stable behaviour over the 6 months. A separate consideration of the leaves showed no higher standard deviation of the LOT than {+-} 0.7ms during the investigated time. The variation between the different leaves is much higher

A method for testing the performance and the accuracy of the binary MLC used in helical tomotherapy

International Nuclear Information System (INIS)

Lissner, Steffen; Schubert, Kai; Klueter, Sebastian; Oetzel, Dieter; Debus, Juergen

2013-01-01

During a helical tomotherapy a binary MLC is used for fluence modulation. The 64 pneumatically driven leaves of the MLC are either completely open or closed. Th e fast and frequent leaf movements result in a high demand of accuracy and stability of the MLC. This article is based on the analytical investigation of the accuracy and the stability of the MLC. Different patterns of MLC movements were generated to investigate the characteristics of the MLC. One of the considered aspects contains the friction between the leaves. The influence of variations of the compressed air on the MLC was also explored. The integrated MVCT detector of the tomotherapy system deposits the treatment data in a matrix. The detector is triggered with the linear accelerator, which is pulsed by 300Hz. The data matrix is available after the treatment. An IDL (Interactive Data Language) routine was programmed in order to analyse the matrix. The points of time, at which the leaves open (POT), and the period, in which the leaves stay open (LOT), were measured and compared with the desired values. That procedure has been repeated several times a week for approximately 6 months to investigate the stability of the MLC. Relative deviations of the LOT from -0.4% to -5.4% were measured. The friction between the leaves had no significant influence on the LOT. The available compressed air, that is used to move the leaves, depends on the number of moving leaves and also on the previous movements of the MLC. Variations of the compressed air resulted in deviations of the LOT from -1.8% to -3.7%. The measured POT deviates from the programmed POT up to -18.4ms ± 0.7ms. This maximal deviation correlates with a shift of the gantry angle of 0.52 which is negligible. The MLC has shown a stable behaviour over the 6 months. A separate consideration of the leaves showed no higher standard deviation of the LOT than ± 0.7ms during the investigated time. The variation between the different leaves is much higher than

Online 4D ultrasound guidance for real-time motion compensation by MLC tracking.

Science.gov (United States)

Ipsen, Svenja; Bruder, Ralf; O'Brien, Rick; Keall, Paul J; Schweikard, Achim; Poulsen, Per R

2016-10-01

With the trend in radiotherapy moving toward dose escalation and hypofractionation, the need for highly accurate targeting increases. While MLC tracking is already being successfully used for motion compensation of moving targets in the prostate, current real-time target localization methods rely on repeated x-ray imaging and implanted fiducial markers or electromagnetic transponders rather than direct target visualization. In contrast, ultrasound imaging can yield volumetric data in real-time (3D + time = 4D) without ionizing radiation. The authors report the first results of combining these promising techniques-online 4D ultrasound guidance and MLC tracking-in a phantom. A software framework for real-time target localization was installed directly on a 4D ultrasound station and used to detect a 2 mm spherical lead marker inside a water tank. The lead marker was rigidly attached to a motion stage programmed to reproduce nine characteristic tumor trajectories chosen from large databases (five prostate, four lung). The 3D marker position detected by ultrasound was transferred to a computer program for MLC tracking at a rate of 21.3 Hz and used for real-time MLC aperture adaption on a conventional linear accelerator. The tracking system latency was measured using sinusoidal trajectories and compensated for by applying a kernel density prediction algorithm for the lung traces. To measure geometric accuracy, static anterior and lateral conformal fields as well as a 358° arc with a 10 cm circular aperture were delivered for each trajectory. The two-dimensional (2D) geometric tracking error was measured as the difference between marker position and MLC aperture center in continuously acquired portal images. For dosimetric evaluation, VMAT treatment plans with high and low modulation were delivered to a biplanar diode array dosimeter using the same trajectories. Dose measurements with and without MLC tracking were compared to a static reference dose using 3%/3 mm and 2

The sensitivity of patient specific IMRT QC to systematic MLC leaf bank offset errors

International Nuclear Information System (INIS)

Rangel, Alejandra; Palte, Gesa; Dunscombe, Peter

2010-01-01

Purpose: Patient specific IMRT QC is performed routinely in many clinics as a safeguard against errors and inaccuracies which may be introduced during the complex planning, data transfer, and delivery phases of this type of treatment. The purpose of this work is to evaluate the feasibility of detecting systematic errors in MLC leaf bank position with patient specific checks. Methods: 9 head and neck (H and N) and 14 prostate IMRT beams were delivered using MLC files containing systematic offsets (±1 mm in two banks, ±0.5 mm in two banks, and 1 mm in one bank of leaves). The beams were measured using both MAPCHECK (Sun Nuclear Corp., Melbourne, FL) and the aS1000 electronic portal imaging device (Varian Medical Systems, Palo Alto, CA). Comparisons with calculated fields, without offsets, were made using commonly adopted criteria including absolute dose (AD) difference, relative dose difference, distance to agreement (DTA), and the gamma index. Results: The criteria most sensitive to systematic leaf bank offsets were the 3% AD, 3 mm DTA for MAPCHECK and the gamma index with 2% AD and 2 mm DTA for the EPID. The criterion based on the relative dose measurements was the least sensitive to MLC offsets. More highly modulated fields, i.e., H and N, showed greater changes in the percentage of passing points due to systematic MLC inaccuracy than prostate fields. Conclusions: None of the techniques or criteria tested is sufficiently sensitive, with the population of IMRT fields, to detect a systematic MLC offset at a clinically significant level on an individual field. Patient specific QC cannot, therefore, substitute for routine QC of the MLC itself.

Multiple linear combination (MLC) regression tests for common variants adapted to linkage disequilibrium structure.

Science.gov (United States)

Yoo, Yun Joo; Sun, Lei; Poirier, Julia G; Paterson, Andrew D; Bull, Shelley B

2017-02-01

By jointly analyzing multiple variants within a gene, instead of one at a time, gene-based multiple regression can improve power, robustness, and interpretation in genetic association analysis. We investigate multiple linear combination (MLC) test statistics for analysis of common variants under realistic trait models with linkage disequilibrium (LD) based on HapMap Asian haplotypes. MLC is a directional test that exploits LD structure in a gene to construct clusters of closely correlated variants recoded such that the majority of pairwise correlations are positive. It combines variant effects within the same cluster linearly, and aggregates cluster-specific effects in a quadratic sum of squares and cross-products, producing a test statistic with reduced degrees of freedom (df) equal to the number of clusters. By simulation studies of 1000 genes from across the genome, we demonstrate that MLC is a well-powered and robust choice among existing methods across a broad range of gene structures. Compared to minimum P-value, variance-component, and principal-component methods, the mean power of MLC is never much lower than that of other methods, and can be higher, particularly with multiple causal variants. Moreover, the variation in gene-specific MLC test size and power across 1000 genes is less than that of other methods, suggesting it is a complementary approach for discovery in genome-wide analysis. The cluster construction of the MLC test statistics helps reveal within-gene LD structure, allowing interpretation of clustered variants as haplotypic effects, while multiple regression helps to distinguish direct and indirect associations. © 2016 The Authors Genetic Epidemiology Published by Wiley Periodicals, Inc.

The sensitivity of patient specific IMRT QC to systematic MLC leaf bank offset errors

Energy Technology Data Exchange (ETDEWEB)

Rangel, Alejandra; Palte, Gesa; Dunscombe, Peter [Department of Medical Physics, Tom Baker Cancer Centre, 1331-29 Street NW, Calgary, Alberta T2N 4N2, Canada and Department of Physics and Astronomy, University of Calgary, 2500 University Drive North West, Calgary, Alberta T2N 1N4 (Canada); Department of Medical Physics, Tom Baker Cancer Centre, 1331-29 Street NW, Calgary, Alberta T2N 4N2 (Canada); Department of Medical Physics, Tom Baker Cancer Centre, 1331-29 Street NW, Calgary, Alberta T2N 4N2 (Canada); Department of Physics and Astronomy, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4 (Canada) and Department of Oncology, Tom Baker Cancer Centre, 1331-29 Street NW, Calgary, Alberta T2N 4N2 (Canada)

2010-07-15

Purpose: Patient specific IMRT QC is performed routinely in many clinics as a safeguard against errors and inaccuracies which may be introduced during the complex planning, data transfer, and delivery phases of this type of treatment. The purpose of this work is to evaluate the feasibility of detecting systematic errors in MLC leaf bank position with patient specific checks. Methods: 9 head and neck (H and N) and 14 prostate IMRT beams were delivered using MLC files containing systematic offsets ({+-}1 mm in two banks, {+-}0.5 mm in two banks, and 1 mm in one bank of leaves). The beams were measured using both MAPCHECK (Sun Nuclear Corp., Melbourne, FL) and the aS1000 electronic portal imaging device (Varian Medical Systems, Palo Alto, CA). Comparisons with calculated fields, without offsets, were made using commonly adopted criteria including absolute dose (AD) difference, relative dose difference, distance to agreement (DTA), and the gamma index. Results: The criteria most sensitive to systematic leaf bank offsets were the 3% AD, 3 mm DTA for MAPCHECK and the gamma index with 2% AD and 2 mm DTA for the EPID. The criterion based on the relative dose measurements was the least sensitive to MLC offsets. More highly modulated fields, i.e., H and N, showed greater changes in the percentage of passing points due to systematic MLC inaccuracy than prostate fields. Conclusions: None of the techniques or criteria tested is sufficiently sensitive, with the population of IMRT fields, to detect a systematic MLC offset at a clinically significant level on an individual field. Patient specific QC cannot, therefore, substitute for routine QC of the MLC itself.

SU-E-J-67: Evaluation of Adaptive MLC Morphing for Online Correction of Prostate Cancer Radiotherapy

Energy Technology Data Exchange (ETDEWEB)

Sandhu, R; Qin, A; Yan, D [William Beaumont Hospital, Royal Oak, MI (United States)

2015-06-15

Purpose: Online adaptive MLC morphing is desirable over translational couch shifts to accommodate target position as well as anatomic changes. A reliable method of adaptive MLC segment to target during prostate cancer IMRT treatment is proposed and evaluated by comparison with daily online-image guidance (IGRT) correction and online-IMRT planning. Methods: The MLC adaptive algorithm involves following steps; move the MLC segments according to target translational shifts, and then morph the segment shape to maintain the spatial relationship between the planning-target contour and MLC segment. Efficacy of this method was evaluated retrospectively using daily-CBCT images on seven prostate patients treated with seven-beam IMRT treatment to deliver 64Gy in 20 fractions. Daily modification was simulated with three approaches; daily-IGRT correction based on implanted radio-markers, adaptive MLC morphing, and online-IMRT planning, with no-residual variation. The selected dosimetric endpoints and nEUD (normalized equivalent uniform dose to online-IMRT planning) of each organ of interest were determined for evaluation and comparison. Results: For target(prostate), bladder and rectal-wall, the mean±sd of nEUD were 97.6%+3.2%, 103.9%±4.9% and 97.4%±1.1% for daily-IGRT correction; and 100.2%+0.2%, 108.9%±5.1% and 99.8%±1.2% for adaptive MLC morphing, respectively. For daily-IGRT correction, adaptive MLC morphing and online-IMRT planning, target D99 was <95% of the prescription dose in 30%, 0% and 0% of 140 fractions, respectively. For the rectal-wall, D5 exceeded 105% of the planned-D5 in 2.8%, 11.4% and 0% of 140 fractions, respectively. For the bladder, Dmax exceeded 105% of the planned-D5 in 2.8%, 5.6% and 0% of 140 fractions, respectively. D30 of bladder and rectal-wall were well within the planned-D30 for all three approaches. Conclusion: The proposed method of adaptive MLC morphing can be beneficial for the prostate patient population with large deformation and

SU-E-J-67: Evaluation of Adaptive MLC Morphing for Online Correction of Prostate Cancer Radiotherapy

International Nuclear Information System (INIS)

Sandhu, R; Qin, A; Yan, D

2015-01-01

Purpose: Online adaptive MLC morphing is desirable over translational couch shifts to accommodate target position as well as anatomic changes. A reliable method of adaptive MLC segment to target during prostate cancer IMRT treatment is proposed and evaluated by comparison with daily online-image guidance (IGRT) correction and online-IMRT planning. Methods: The MLC adaptive algorithm involves following steps; move the MLC segments according to target translational shifts, and then morph the segment shape to maintain the spatial relationship between the planning-target contour and MLC segment. Efficacy of this method was evaluated retrospectively using daily-CBCT images on seven prostate patients treated with seven-beam IMRT treatment to deliver 64Gy in 20 fractions. Daily modification was simulated with three approaches; daily-IGRT correction based on implanted radio-markers, adaptive MLC morphing, and online-IMRT planning, with no-residual variation. The selected dosimetric endpoints and nEUD (normalized equivalent uniform dose to online-IMRT planning) of each organ of interest were determined for evaluation and comparison. Results: For target(prostate), bladder and rectal-wall, the mean±sd of nEUD were 97.6%+3.2%, 103.9%±4.9% and 97.4%±1.1% for daily-IGRT correction; and 100.2%+0.2%, 108.9%±5.1% and 99.8%±1.2% for adaptive MLC morphing, respectively. For daily-IGRT correction, adaptive MLC morphing and online-IMRT planning, target D99 was <95% of the prescription dose in 30%, 0% and 0% of 140 fractions, respectively. For the rectal-wall, D5 exceeded 105% of the planned-D5 in 2.8%, 11.4% and 0% of 140 fractions, respectively. For the bladder, Dmax exceeded 105% of the planned-D5 in 2.8%, 5.6% and 0% of 140 fractions, respectively. D30 of bladder and rectal-wall were well within the planned-D30 for all three approaches. Conclusion: The proposed method of adaptive MLC morphing can be beneficial for the prostate patient population with large deformation and

SU-C-BRB-02: Symmetric and Asymmetric MLC Based Lung Shielding and Dose Optimization During Translating Bed TBI

Energy Technology Data Exchange (ETDEWEB)

Ahmed, S; Kakakhel, MB [Pakistan Institute of Engineering & Applied Sciences (PIEAS), Islamabad (Pakistan); Ahmed, SBS; Hussain, A [Aga Khan University Hospital (AKUH), Karachi (Pakistan)

2015-06-15

Purpose: The primary aim was to introduce a dose optimization method for translating bed total body irradiation technique that ensures lung shielding dynamically. Symmetric and asymmetric dynamic MLC apertures were employed for this purpose. Methods: The MLC aperture sizes were defined based on the radiological depth values along the divergent ray lines passing through the individual CT slices. Based on these RD values, asymmetrically shaped MLC apertures were defined every 9 mm of the phantom in superior-inferior direction. Individual MLC files were created with MATLAB™ and were imported into Eclipse™ treatment planning system for dose calculations. Lungs can be shielded to an optimum level by reducing the MLC aperture width over the lungs. The process was repeated with symmetrically shaped apertures. Results: Dose-volume histogram (DVH) analysis shows that the asymmetric MLC based technique provides better dose coverage to the body and optimum shielding of the lungs compared to symmetrically shaped beam apertures. Midline dose homogeneity is within ±3% with asymmetric MLC apertures whereas it remains within ±4.5% with symmetric ones (except head region where it drops down to −7%). The substantial over and under dosage of ±5% at tissue interfaces has been reduced to ±2% with asymmetric MLC technique. Lungs dose can be reduced to any desired limit. In this experiment lungs dose was reduced to 80% of the prescribed dose, as was desired. Conclusion: The novel asymmetric MLC based technique assures optimum shielding of OARs (e.g. lungs) and better 3-D dose homogeneity and body-dose coverage in comparison with the symmetric MLC aperture optimization. The authors acknowledge the financial and infrastructural support provided by Pakistan Institute of Engineering & Applied Sciences (PIEAS), Islamabad and Aga Khan University Hospital (AKUH), Karachi during the course of this research project. Authors have no conflict of interest with any national / international

Macrophage polarization differs between apical granulomas, radicular cysts, and dentigerous cysts.

Science.gov (United States)

Weber, Manuel; Schlittenbauer, Tilo; Moebius, Patrick; Büttner-Herold, Maike; Ries, Jutta; Preidl, Raimund; Geppert, Carol-Immanuel; Neukam, Friedrich W; Wehrhan, Falk

2018-01-01

Apical periodontitis can appear clinically as apical granulomas or radicular cysts. There is evidence that immunologic factors are involved in the pathogenesis of both pathologies. In contrast to radicular cysts, the dentigerous cysts have a developmental origin. Macrophage polarization (M1 vs M2) is a main regulator of tissue homeostasis and differentiation. There are no studies comparing macrophage polarization in apical granulomas, radicular cysts, and dentigerous cysts. Forty-one apical granulomas, 23 radicular cysts, and 23 dentigerous cysts were analyzed in this study. A tissue microarray (TMA) of the 87 consecutive specimens was created, and CD68-, CD11c-, CD163-, and MRC1-positive macrophages were detected by immunohistochemical methods. TMAs were digitized, and the expression of macrophage markers was quantitatively assessed. Radicular cysts are characterized by M1 polarization of macrophages while apical granulomas show a significantly higher degree of M2 polarization. Dentigerous cysts have a significantly lower M1 polarization than both analyzed periapical lesions (apical granulomas and radicular cysts) and accordingly, a significantly higher M2 polarization than radicular cysts. Macrophage cell density in dentigerous cysts is significantly lower than in the periapical lesions. The development of apical periodontitis towards apical granulomas or radicular cysts might be directed by macrophage polarization. Radicular cyst formation is associated with an increased M1 polarization of infiltrating macrophages. In contrast to radicular cysts, dentigerous cysts are characterized by a low macrophage infiltration and a high degree of M2 polarization, possibly reflecting their developmental rather than inflammatory origin. As M1 polarization of macrophages is triggered by bacterial antigens, these results underline the need for sufficient bacterial clearance during endodontic treatment to prevent a possible M1 macrophage-derived stimulus for radicular cyst

Dysphagia Post Subcortical and Supratentorial Stroke.

Science.gov (United States)

Wan, Ping; Chen, Xuhui; Zhu, Lequn; Xu, Shuangjin; Huang, Li; Li, Xiangcui; Ye, Qing; Ding, Ruiying

2016-01-01

Studies have recognized that the damage in the subcortical and supratentorial regions may affect voluntary and involuntary aspects of the swallowing function. The current study attempted to explore the dysphagia characteristics in patients with subcortical and supratentorial stroke. Twelve post first or second subcortical and supratentorial stroke patients were included in the study. The location of the stroke was ascertained by computed tomography and magnetic resonance imaging. The characteristics of swallowing disorder were assessed by video fluoroscopic swallowing assessment/fiberoptic endoscopic evaluation of swallowing. The following main parameters were analyzed: oral transit time, pharyngeal delay time, presence of cricopharyngeal muscle achalasia (CMA), distance of laryngeal elevation, the amounts of vallecular residue and pyriform sinus residue (PSR), and the extent of pharyngeal contraction. Eighty-three percent of the 12 patients were found suffering from pharyngeal dysphagia, with 50% having 50%-100% PSRs, 50% having pharyngeal delay, and 41.6% cases demonstrating CMA. Simple regression analysis showed PSRs were most strongly associated with CMA. Pharyngeal delay in the study can be caused by infarcts of basal ganglia/thalamus, infarcts of sensory tract, infarcts of swallowing motor pathways in the centrum semiovale, or a combination of the three. Subcortical and supratentorial stroke may result in pharyngeal dysphagia such as PSR and pharyngeal delay. PSR was mainly caused by CMA. Copyright © 2015 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Dosimetry of a prototype retractable eMLC for fixed-beam electron therapy

International Nuclear Information System (INIS)

Hogstrom, Kenneth R.; Boyd, Robert A.; Antolak, John A.; Svatos, Michelle M.; Faddegon, Bruce A.; Rosenman, Julian G.

2004-01-01

An electron multileaf collimator (eMLC) has been designed that is unique in that it retracts to 37 cm from the isocenter [63-cm source-to-collimator distance (SCD)] and can be deployed to distances of 20 and 10 cm from the isocenter (80 and 90 cm SCD, respectively). It is expected to be capable of arc therapy at 63 cm SCD; isocentric, fixed-beam therapy at 80 cm SCD; and source-to-surface distance (SSD), fixed-beam therapy at 90 cm SCD. In all positions, its leaves could be used for unmodulated or intensity-modulated therapy. Our goal in the present work is to describe the general characteristics of the eMLC and to demonstrate that its leakage characteristics and dosimetry are adequate for SSD, fixed-beam therapy as an alternative to Cerrobend cutouts with applicators once the prototype's leaves are motorized. Our eMLC data showed interleaf electron leakage at 15 MeV to be less than 0.1% based on a 0.0025 cm manufacturing tolerance, and lateral electron leakage at 5 and 15 MeV to be less than 2%. X-ray leakage through the leaves was 1.6% at 15 MeV. Our data showed that beam penumbra was independent of direction and leaf position. The dosimetric properties of square fields formed by the eMLC were very consistent with those formed by Cerrobend inserts in the 20x20 cm 2 applicator. Output factors exhibited similar field-size dependence. Airgap factors exhibited almost identical field-size dependence at two SSDs (105 and 110 cm), consistent with the common assumption that airgap factors are applicator independent. Percent depth-dose curves were similar, but showed variations up to 3% in the buildup region. The pencil-beam algorithm (PBA) fit measured data from the eMLC and applicator-cutout systems equally well, and the resulting two-dimensional (2-D) dose distributions, as predicted by the PBA, agreed well at common airgap distance. Simulating patient setups for breast and head and neck treatments showed that almost all fields could be treated using similar SSDs as

Duffing–van der Pol oscillator type dynamics in Murali–Lakshmanan–Chua (MLC) circuit

International Nuclear Information System (INIS)

Srinivasan, K.; Chandrasekar, V.K.; Venkatesan, A.; Raja Mohamed, I.

2016-01-01

Highlights: • Proposed an electronic circuit with diode based nonlinear element equivalent to a well known Murali–Lakshmanan–Chua (MLC) circuit. • For chosen circuit parameters this circuit admits familiar MLC type attractor and also Duffing–van der Pol circuit type chaotic attractor. • The performance of the circuit is investigated by means of explicit laboratory experiments, numerical simulations and analytical studies. - Abstract: We have constructed a simple second-order dissipative nonautonomous circuit exhibiting ordered and chaotic behaviour. This circuit is the well known Murali–Lakshmanan–Chua(MLC) circuit but with diode based nonlinear element. For chosen circuit parameters this circuit admits familiar MLC type attractor and also Duffing–van der Pol circuit type chaotic attractors. It is interesting to note that depending upon the circuit parameters the circuit shows both period doubling route to chaos and quasiperiodic route to chaos. In our study we have constructed two-parameter bifurcation diagrams in the forcing amplitude–frequency plane, one parameter bifurcation diagrams, Lyapunov exponents, 0–1 test and phase portrait. The performance of the circuit is investigated by means of laboratory experiments, numerical integration of appropriate mathematical model and explicit analytic studies.

Simple bone cyst of mandible mimicking periapical cyst

OpenAIRE

Charan Babu HS; Bhagawan Das Rai; Manju A. Nair; Madhusudan S. Astekar

2012-01-01

Simple bone cysts (SBC) are pseudocysts occurring less commonly in the maxillofacial region. The uncertain and unclear etiopathogenesis led to numerous synonyms to refer this particular cyst. These cysts are devoid of an epithelial lining and are usually empty or contain blood or straw-colored fluid. In jaws initially it mimics a periapical cyst and later can lead to cortical bone expansion warranting for radical approach, which is seldom required. SBC is predominantly diagnosed in first two ...

EPID-based verification of the MLC performance for dynamic IMRT and VMAT

International Nuclear Information System (INIS)

Rowshanfarzad, Pejman; Sabet, Mahsheed; Barnes, Michael P.; O’Connor, Daryl J.; Greer, Peter B.

2012-01-01

Purpose: In advanced radiotherapy treatments such as intensity modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT), verification of the performance of the multileaf collimator (MLC) is an essential part of the linac QA program. The purpose of this study is to use the existing measurement methods for geometric QA of the MLCs and extend them to more comprehensive evaluation techniques, and to develop dedicated robust algorithms to quantitatively investigate the MLC performance in a fast, accurate, and efficient manner. Methods: The behavior of leaves was investigated in the step-and-shoot mode by the analysis of integrated electronic portal imaging device (EPID) images acquired during picket fence tests at fixed gantry angles and arc delivery. The MLC was also studied in dynamic mode by the analysis of cine EPID images of a sliding gap pattern delivered in a variety of conditions including different leaf speeds, deliveries at fixed gantry angles or in arc mode, and changing the direction of leaf motion. The accuracy of the method was tested by detection of the intentionally inserted errors in the delivery patterns. Results: The algorithm developed for the picket fence analysis was able to find each individual leaf position, gap width, and leaf bank skewness in addition to the deviations from expected leaf positions with respect to the beam central axis with sub-pixel accuracy. For the three tested linacs over a period of 5 months, the maximum change in the gap width was 0.5 mm, the maximum deviation from the expected leaf positions was 0.1 mm and the MLC skewness was up to 0.2°. The algorithm developed for the sliding gap analysis could determine the velocity and acceleration/deceleration of each individual leaf as well as the gap width. There was a slight decrease in the accuracy of leaf performance with increasing leaf speeds. The analysis results were presented through several graphs. The accuracy of the method was assessed as 0.01 mm

Impact of the MLC on the MRI field distortion of a prototype MRI-linac

International Nuclear Information System (INIS)

Kolling, Stefan; Keall, Paul; Oborn, Brad

2013-01-01

Purpose: To cope with intrafraction tumor motion, integrated MRI-linac systems for real-time image guidance are currently under development. The multileaf collimator (MLC) is a key component in every state-of-the-art radiotherapy treatment system, allowing for accurate field shaping and tumor tracking. This work quantifies the magnetic impact of a widely used MLC on the MRI field homogeneity for such a modality.Methods: The finite element method was employed to model a MRI-linac assembly comprised of a 1.0 T split-bore MRI magnet and the key ferromagnetic components of a Varian Millennium 120 MLC, namely, the leaves and motors. Full 3D magnetic field maps of the system were generated. From these field maps, the peak-to-peak distortion within the MRI imaging volume was evaluated over a 30 cm diameter sphere volume (DSV) around the isocenter and compared to a maximum preshim inhomogeneity of 300 μT. Five parametric studies were performed: (1) The source-to-isocenter distance (SID) was varied from 100 to 200 cm, to span the range of a compact system to that with lower magnetic coupling. (2) The MLC model was changed from leaves only to leaves with motors, to determine the contribution to the total distortion caused by MLC leaves and motors separately. (3) The system was configured in the inline or perpendicular orientation, i.e., the linac treatment beam was oriented parallel or perpendicular to the magnetic field direction. (4) The treatment field size was varied from 0 × 0 to 20×20 cm 2 , to span the range of clinical treatment fields. (5) The coil currents were scaled linearly to produce magnetic field strengths B 0 of 0.5, 1.0, and 1.5 T, to estimate how the MLC impact changes with B 0 .Results: (1) The MLC-induced MRI field distortion fell continuously with increasing SID. (2) MLC leaves and motors were found to contribute to the distortion in approximately equal measure. (3) Due to faster falloff of the fringe field, the field distortion was

SU-E-T-784: Using MLC Log Files for Daily IMRT Delivery Verification

Energy Technology Data Exchange (ETDEWEB)

Stathakis, S; Defoor, D; Linden, P; Kirby, N; Papanikolaou, N [University of Texas HSC SA, San Antonio, TX (United States)

2015-06-15

Purpose: To verify daily intensity modulated radiation therapy (IMRT) treatments using multi-leaf collimator (MLC) log files. Methods: The MLC log files from a NovalisTX Varian linear accelerator were used in this study. The MLC files were recorded daily for all patients undergoing IMRT or volumetric modulated arc therapy (VMAT). The first record of each patient was used as reference and all records for subsequent days were compared against the reference. An in house MATLAB software code was used for the comparisons. Each MLC log file was converted to a fluence map (FM) and a gamma index (γ) analysis was used for the evaluation of each daily delivery for every patient. The tolerance for the gamma index was set to 2% dose difference and 2mm distance to agreement while points with signal of 10% or lower of the maximum value were excluded from the comparisons. Results: The γ between each of the reference FMs and the consecutive daily fraction FMs had an average value of 99.1% (ranged from 98.2 to 100.0%). The FM images were reconstructed at various resolutions in order to study the effect of the resolution on the γ and at the same time reduce the time for processing the images. We found that the comparison of images with the highest resolution (768×1024) yielded on average a lower γ (99.1%) than the ones with low resolution (192×256) (γ 99.5%). Conclusion: We developed an in-house software that allows us to monitor the quality of daily IMRT and VMAT treatment deliveries using information from the MLC log files of the linear accelerator. The information can be analyzed and evaluated as early as after the completion of each daily treatment. Such tool can be valuable to assess the effect of MLC positioning on plan quality, especially in the context of adaptive radiotherapy.

SU-E-T-430: Modeling MLC Leaf End in 2D for Sliding Window IMRT and Arc Therapy

International Nuclear Information System (INIS)

Liang, X; Zhu, T

2014-01-01

Purpose: To develop a 2D geometric model for MLC accounting for leaf end dose leakage for dynamic IMRT and Rapidarc therapy. Methods: Leaf-end dose leakage is one of the problems for MLC dose calculation and modeling. Dosimetric leaf gap used to model the MLC and to count for leakage in dose calculation, but may not be accurate for smaller leaf gaps. We propose another geometric modeling method to compensate for the MLC round-shape leaf ends dose leakage, and improve the accuracy of dose calculation and dose verification. A triangular function is used to geometrically model the MLC leaf end leakage in the leaf motion direction, and a step function is used in the perpendicular direction. Dose measurements with different leaf gap, different window width, and different window height were conducted, and the results were used to fit the analytical model to get the model parameters. Results: Analytical models have been obtained for stop-and-shoot and dynamic modes for MLC motion. Parameters a=0.4, lw'=5.0 mm for 6X and a=0.54, lw'=4.1 mm for 15x were obtained from the fitting process. The proposed MLC leaf end model improves the dose profile at the two ends of the sliding window opening. This improvement is especially significant for smaller sliding window openings, which are commonly used for highly modulated IMRT plans and arc therapy plans. Conclusion: This work models the MLC round leaf end shape and movement pattern for IMRT dose calculation. The theory, as well as the results in this work provides a useful tool for photon beam IMRT dose calculation and verification

Poster - 53: Improving inter-linac DMLC IMRT dose precision by fine tuning of MLC leaf calibration

International Nuclear Information System (INIS)

Nakonechny, Keith; Tran, Muoi; Sasaki, David; Beck, James; Poirier, Yannick; Malkoske, Kyle

2016-01-01

Purpose: To develop a method to improve the inter-linac precision of DMLC IMRT dosimetry. Methods: The distance between opposing MLC leaf banks (“gap size”) can be finely tuned on Varian linacs. The dosimetric effect due to small deviations from the nominal gap size (“gap error”) was studied by introducing known errors for several DMLC sliding gap sizes, and for clinical plans based on the TG119 test cases. The plans were delivered on a single Varian linac and the relationship between gap error and the corresponding change in dose was measured. The plans were also delivered on eight Varian 2100 series linacs (at two institutions) in order to quantify the inter-linac variation in dose before and after fine tuning the MLC calibration. Results: The measured dose differences for each field agreed well with the predictions of LoSasso et al. Using the default MLC calibration, the variation in the physical MLC gap size was determined to be less than 0.4 mm between all linacs studied. The dose difference between the linacs with the largest and smallest physical gap was up to 5.4% (spinal cord region of the head and neck TG119 test case). This difference was reduced to 2.5% after fine tuning the MLC gap calibration. Conclusions: The inter-linac dose precision for DMLC IMRT on Varian linacs can be improved using a simple modification of the MLC calibration procedure that involves fine adjustment of the nominal gap size.

Poster - 53: Improving inter-linac DMLC IMRT dose precision by fine tuning of MLC leaf calibration

Energy Technology Data Exchange (ETDEWEB)

Nakonechny, Keith; Tran, Muoi; Sasaki, David; Beck, James; Poirier, Yannick; Malkoske, Kyle [Simcoe-Muskoka Regional Cancer Centre (Canada)

2016-08-15

Purpose: To develop a method to improve the inter-linac precision of DMLC IMRT dosimetry. Methods: The distance between opposing MLC leaf banks (“gap size”) can be finely tuned on Varian linacs. The dosimetric effect due to small deviations from the nominal gap size (“gap error”) was studied by introducing known errors for several DMLC sliding gap sizes, and for clinical plans based on the TG119 test cases. The plans were delivered on a single Varian linac and the relationship between gap error and the corresponding change in dose was measured. The plans were also delivered on eight Varian 2100 series linacs (at two institutions) in order to quantify the inter-linac variation in dose before and after fine tuning the MLC calibration. Results: The measured dose differences for each field agreed well with the predictions of LoSasso et al. Using the default MLC calibration, the variation in the physical MLC gap size was determined to be less than 0.4 mm between all linacs studied. The dose difference between the linacs with the largest and smallest physical gap was up to 5.4% (spinal cord region of the head and neck TG119 test case). This difference was reduced to 2.5% after fine tuning the MLC gap calibration. Conclusions: The inter-linac dose precision for DMLC IMRT on Varian linacs can be improved using a simple modification of the MLC calibration procedure that involves fine adjustment of the nominal gap size.

Identification of an MLC suppressor cell population in acute leukemia

International Nuclear Information System (INIS)

Bryan, C.F.; Broxmeyer, H.E.; Hansen, J.; Pollack, M.; Dupont, B.

1978-01-01

The MLC data from the 20 nonsuppressing patients and the 10 suppressing leukemia patients were analyzed with regard to HLA-A, -B, and -C antigens in the leukemia patients and compared with the presence or absence of suppression. These results demonstrate a significant increase (p < 0.02, Mann-Whitney U test) of HLA antigens Al, A3, and A11 in the leukemia suppressor group. Seven of the 10 leukemia patients showing suppression were A1, A3, or A11, while only 4 of the 20 nonsuppressing leukemia patients carried any of these three HLA-A antigens. The studies demonstrate that a nonspecific suppression of MLC responses is observed in 33% of the patients with acute leukemia

MLC quality assurance using EPID: A fitting technique with subpixel precision

International Nuclear Information System (INIS)

Mamalui-Hunter, Maria; Li, Harold; Low, Daniel A.

2008-01-01

Amorphous silicon based electronic portal imaging devices (EPIDs) have been shown to be a good alternative to radiographic film for routine quality assurance (QA) of multileaf collimator (MLC) positioning accuracy. In this work, we present a method of acquiring an EPID image of a traditional strip-test image using analytical fits of the interleaf and leaf abutment image signatures. After exposure, the EPID image pixel values are divided by an open field image to remove EPID response and radiation field variations. Profiles acquired in the direction orthogonal to the leaf motion exhibit small peaks caused by interleaf leakage. Gaussian profiles are fitted to the interleaf leakage peaks, the results of which are, using multiobjective optimization, used to calculate the image rotational angle with respect to the collimator axis of rotation. The relative angle is used to rotate the image to align the MLC leaf travel to the image pixel axes. The leaf abutments also present peaks that are fitted by heuristic functions, in this case modified Lorentzian functions. The parameters of the Lorentzian functions are used to parameterize the leaf gap width and positions. By imaging a set of MLC fields with varying gaps forming symmetric and asymmetric abutments, calibration curves with regard to relative peak height (RPH) versus nominal gap width are obtained. Based on this calibration data, the individual leaf positions are calculated to compare with the nominal programmed positions. The results demonstrate that the collimator rotation angle can be determined as accurate as 0.01 deg. . A change in MLC gap width of 0.2 mm leads to a change in RPH of about 10%. For asymmetrically produced gaps, a 0.2 mm MLC leaf gap width change causes 0.2 pixel peak position change. Subpixel resolution is obtained by using a parameterized fit of the relatively large abutment peaks. By contrast, for symmetrical gap changes, the peak position remains unchanged with a standard deviation of 0

Fast motion-including dose error reconstruction for VMAT with and without MLC tracking

DEFF Research Database (Denmark)

Ravkilde, Thomas; Keall, Paul J.; Grau, Cai

2014-01-01

of the algorithm for reconstruction of dose and motion-induced dose errors throughout the tracking and non-tracking beam deliveries was quantified. Doses were reconstructed with a mean dose difference relative to the measurements of -0.5% (5.5% standard deviation) for cumulative dose. More importantly, the root...... validate a simple model for fast motion-including dose error reconstruction applicable to intrafractional QA of MLC tracking treatments of moving targets. MLC tracking experiments were performed on a standard linear accelerator with prototype MLC tracking software guided by an electromagnetic transponder......-mean-square deviation between reconstructed and measured motion-induced 3%/3 mm γ failure rates (dose error) was 2.6%. The mean computation time for each calculation of dose and dose error was 295 ms. The motion-including dose reconstruction allows accurate temporal and spatial pinpointing of errors in absorbed dose...

On the suitability of Elekta’s Agility 160 MLC for tracked radiation delivery: closed-loop machine performance

International Nuclear Information System (INIS)

Glitzner, M; Crijns, S P M; De Senneville, B Denis; Lagendijk, J J W; Raaymakers, B W

2015-01-01

For motion adaptive radiotherapy, dynamic multileaf collimator tracking can be employed to reduce treatment margins by steering the beam according to the organ motion. The Elekta Agility 160 MLC has hitherto not been evaluated for its tracking suitability. Both dosimetric performance and latency are key figures and need to be assessed generically, independent of the used motion sensor. In this paper, we propose the use of harmonic functions directly fed to the MLC to determine its latency during continuous motion. Furthermore, a control variable is extracted from a camera system and fed to the MLC. Using this setup, film dosimetry and subsequent γ statistics are performed, evaluating the response when tracking (MRI)-based physiologic motion in a closed-loop. The delay attributed to the MLC itself was shown to be a minor contributor to the overall feedback chain as compared to the impact of imaging components such as MRI sequences. Delay showed a linear phase behaviour of the MLC employed in continuously dynamic applications, which enables a general MLC-characterization. Using the exemplary feedback chain, dosimetry showed a vast increase in pass rate employing γ statistics. In this early stage, the tracking performance of the Agility using the test bench yielded promising results, making the technique eligible for translation to tracking using clinical imaging modalities. (paper)

Cerebral Arachnoid Cysts

Directory of Open Access Journals (Sweden)

Ersin Haciyakupoglu

2016-09-01

Full Text Available Arachnoid cysts can occur through inflammatory, traumatic, chemical irritation, skin tumor and postoperative processes. It is diagnosed and differentiated by magnetic resonance imaging and computerized tomography from other lesions. Its differential diagnosis includes colloid cyst , craniopharyngioma, prosencephaly, holoprosencephaly , epidermoid cyst, hydatid cyst, low grade glial tumors, infarcts and subdural hygroma. Most of them are asymptomatic and diagnosed incidentally. Treatment methods such as simple cyst aspiration , total excision of the cyst, basal cysternostomy, ventricular fenestration, cysto or ventriculoperitoneal shunt can be performed by various endoscopic surgery and craniotomy. [Archives Medical Review Journal 2016; 25(3.000: 259-268

Leakage of the Siemens 160 MLC multileaf collimator on a dual energy linear accelerator

International Nuclear Information System (INIS)

Klueter, Sebastian; Sroka-Perez, Gabriele; Schubert, Kai; Debus, Juergen

2011-01-01

Multileaf collimators (MLCs) have been in clinical use for many years and meanwhile are commonly used to deliver intensity-modulated radiotherapy (IMRT) beams. For this purpose it is important to know their dosimetric properties precisely, one of them being inter- and intraleaf leakage. The Siemens 160 MLC features a single focus design with flat-sided and tilted leaves instead of tongue-and-groove. The leakage performance of the 160 MLC was investigated on a dual energy linear accelerator Siemens ARTISTE with 6 MV and 18 MV photon energies. While the intraleaf leakage amounted to nearly the same dose for 6 and for 18 MV, a much higher interleaf leakage for 6 MV was measured. It could be reduced by simply rotating the collimator, and also by changing the voltage applied to the beam steering coils. The leakage of the 160 MLC is shown to be sensitive to beam alignment. This is of special interest for dual energy accelerators, as the two focal spots of both energies, neither in position nor in shape, do not necessarily always coincide. As a consequence of that, a higher leakage can be expected for one out of two energies for the 160 MLC. (note)

SU-F-T-289: MLC Fluence Sonogram Based Delivery Quality Assurance for Bilateral Breast Irradiation

Energy Technology Data Exchange (ETDEWEB)

Thiyagarajan, Rajesh; Karrthick, KP; Kataria, Tejinder; Mahendran, Ramu; Selvan, Tamil; Duraikannu, Palani [Division of Radiation Oncology, Medanta The Medicity, Gurgaon, Haryana (India); Raj, Nambi [Department of Physics, School of Advanced sciences, VIT University, Vellore (India); Arunai, N

2016-06-15

Purpose: Performing DQA for Bilateral (B-L) breast tomotherapy is a challenging task due to the limitation of any commercially available detector array or film. Aim of this study is to perform DQA for B-L breast tomotherapy plan using MLC fluence sinogram. Methods: Treatment plan was generated on Tomotherapy system for B-L breast tumour. B-L breast targets were given 50.4 Gy prescribed over 28 fractions. Plan is generated with 6 MV photon beam & pitch was set to 0.3. As the width of the total target is 39 cm (left & right) length is 20 cm. DQA plan delivered without any phantom on the mega voltage computed tomography (MCVT) detector system. The pulses recorded by MVCT system were exported to the delivery analysis software (Tomotherapy Inc.) for reconstruction. The detector signals are reconstructed to a sonogram and converted to MLC fluence sonogram. The MLC fluence sinogram compared with the planned fluence sinogram. Also point dose measured with cheese phantom and ionization chamber to verify the absolute dose component Results: Planned fluence sinogram and reconstructed MLC fluence sinogram were compared using Gamma metric. MLC positional difference and intensity of the beamlet were used as parameters to evaluate gamma. 3 mm positional difference and 3% beamlet intensity difference were used set for gamma calculation. A total of 26784 non-zero beamlets were included in the analysis out of which 161 beamlets had gamma more than 1. The gamma passing rate found to be 99.4%. Point dose measurements were within 1.3% of the calculated dose. Conclusion: MLC fluence sinogram based delivery quality assurance performed for bilateral breast irradiation. This would be a suitable alternate for large volume targets like bilateral breast, Total body irradiation etc. However conventional method of DQA should be used to validate this method periodically.

The dosimetric impact of inversely optimized arc radiotherapy plan modulation for real-time dynamic MLC tracking delivery

International Nuclear Information System (INIS)

Falk, Marianne; Larsson, Tobias; Keall, Paul; Chul Cho, Byung; Aznar, Marianne; Korreman, Stine; Poulsen, Per; Munck af Rosenschoeld, Per

2012-01-01

Purpose: Real-time dynamic multileaf collimator (MLC) tracking for management of intrafraction tumor motion can be challenging for highly modulated beams, as the leaves need to travel far to adjust for target motion perpendicular to the leaf travel direction. The plan modulation can be reduced by using a leaf position constraint (LPC) that reduces the difference in the position of adjacent MLC leaves in the plan. The purpose of this study was to investigate the impact of the LPC on the quality of inversely optimized arc radiotherapy plans and the effect of the MLC motion pattern on the dosimetric accuracy of MLC tracking delivery. Specifically, the possibility of predicting the accuracy of MLC tracking delivery based on the plan modulation was investigated. Methods: Inversely optimized arc radiotherapy plans were created on CT-data of three lung cancer patients. For each case, five plans with a single 358 deg. arc were generated with LPC priorities of 0 (no LPC), 0.25, 0.5, 0.75, and 1 (highest possible LPC), respectively. All the plans had a prescribed dose of 2 Gy x 30, used 6 MV, a maximum dose rate of 600 MU/min and a collimator angle of 45 deg. or 315 deg. To quantify the plan modulation, an average adjacent leaf distance (ALD) was calculated by averaging the mean adjacent leaf distance for each control point. The linear relationship between the plan quality [i.e., the calculated dose distributions and the number of monitor units (MU)] and the LPC was investigated, and the linear regression coefficient as well as a two tailed confidence level of 95% was used in the evaluation. The effect of the plan modulation on the performance of MLC tracking was tested by delivering the plans to a cylindrical diode array phantom moving with sinusoidal motion in the superior-inferior direction with a peak-to-peak displacement of 2 cm and a cycle time of 6 s. The delivery was adjusted to the target motion using MLC tracking, guided in real-time by an infrared optical system

SU-F-T-469: A Clinically Observed Discrepancy Between Image-Based and Log- Based MLC Position

Energy Technology Data Exchange (ETDEWEB)

Neal, B; Ahmed, M; Siebers, J [University of Virginia Health System, Charlottesville, VA (United States)

2016-06-15

Purpose: To present a clinical case which challenges the base assumption of log-file based QA, by showing that the actual position of a MLC leaf can suddenly deviate from its programmed and logged position by >1 mm as observed with real-time imaging. Methods: An EPID-based exit-fluence dosimetry system designed to prevent gross delivery errors was used in cine mode to capture portal images during treatment. Visual monitoring identified an anomalous MLC leaf pair gap not otherwise detected by the automatic position verification. The position of the erred leaf was measured on EPID images and log files were analyzed for the treatment in question, the prior day’s treatment, and for daily MLC test patterns acquired on those treatment days. Additional standard test patterns were used to quantify the leaf position. Results: Whereas the log file reported no difference between planned and recorded positions, image-based measurements showed the leaf to be 1.3±0.1 mm medial from the planned position. This offset was confirmed with the test pattern irradiations. Conclusion: It has been clinically observed that log-file derived leaf positions can differ from their actual positions by >1 mm, and therefore cannot be considered to be the actual leaf positions. This cautions the use of log-based methods for MLC or patient quality assurance without independent confirmation of log integrity. Frequent verification of MLC positions through independent means is a necessary precondition to trusting log file records. Intra-treatment EPID imaging provides a method to capture departures from MLC planned positions. Work was supported in part by Varian Medical Systems.

[Rare location of arachnoid cysts. Extratemporal cysts].

Science.gov (United States)

Martinez-Perez, Rafael; Hinojosa, José; Pascual, Beatriz; Panaderos, Teresa; Welter, Diego; Muñoz, María J

2016-01-01

The therapeutic management of arachnoid cysts depends largely on its location. Almost 50% of arachnoid cysts are located in the temporal fossa-Sylvian fissure, whereas the other half is distributed in different locations, sometimes exceptional. Under the name of infrequent location arachnoid cysts, a description is presented of those composed of 2 sheets of arachnoid membrane, which are not located in the temporal fossa, and are primary or congenital. Copyright © 2015 Sociedad Española de Neurocirugía. Published by Elsevier España. All rights reserved.

Odontogenic Cysts and Neoplasms.

Science.gov (United States)

Bilodeau, Elizabeth Ann; Collins, Bobby M

2017-03-01

This article reviews a myriad of common and uncommon odontogenic cysts and tumors. The clinical presentation, gross and microscopic features, differential diagnosis, prognosis, and diagnostic pitfalls are addressed for inflammatory cysts (periapical cyst, mandibular infected buccal cyst/paradental cyst), developmental cysts (dentigerous, lateral periodontal, glandular odontogenic, orthokeratinized odontogenic cyst), benign tumors (keratocystic odontogenic tumor, ameloblastoma, adenomatoid odontogenic tumor, calcifying epithelial odontogenic tumor, ameloblastic fibroma and fibroodontoma, odontoma, squamous odontogenic tumor, calcifying cystic odontogenic tumor, primordial odontogenic tumor, central odontogenic fibroma, and odontogenic myxomas), and malignant tumors (clear cell odontogenic carcinoma, ameloblastic carcinoma, ameloblastic fibrosarcoma). Copyright © 2016 Elsevier Inc. All rights reserved.

SU-F-T-366: Dosimetric Parameters Enhancement of 120-Leaf Millennium MLC Using EGSnrc and IAEA Phase-Space Data

International Nuclear Information System (INIS)

Haddad, K; Alopoor, H

2016-01-01

Purpose: Recently, the multileaf collimators (MLC) have become an important part of any LINAC collimation systems because they reduce the treatment planning time and improves the conformity. Important factors that affects the MLCs collimation performance are leaves material composition and their thickness. In this study, we investigate the main dosimetric parameters of 120-leaf Millennium MLC including dose in the buildup point, physical penumbra as well as average and end leaf leakages. Effects of the leaves geometry and density on these parameters are evaluated Methods: From EGSnrc Monte Carlo code, BEAMnrc and DOSXYZnrc modules are used to evaluate the dosimetric parameters of a water phantom exposed to a Varian xi for 100cm SSD. Using IAEA phasespace data just above MLC (Z=46cm) and BEAMnrc, for the modified 120-leaf Millennium MLC a new phase space data at Z=52cm is produces. The MLC is modified both in leaf thickness and material composition. EGSgui code generates 521ICRU library for tungsten alloys. DOSXYZnrc with the new phase space evaluates the dose distribution in a water phantom of 60×60×20 cm3 with voxel size of 4×4×2 mm3. Using DOSXYZnrc dose distributions for open beam and closed beam as well as the leakages definition, end leakage, average leakage and physical penumbra are evaluated. Results: A new MLC with improved dosimetric parameters is proposed. The physical penumbra for proposed MLC is 4.7mm compared to 5.16 mm for Millennium. Average leakage in our design is reduced to 1.16% compared to 1.73% for Millennium, the end leaf leakage suggested design is also reduced to 4.86% compared to 7.26% of Millennium. Conclusion: The results show that the proposed MLC with enhanced dosimetric parameters could improve the conformity of treatment planning.

SU-F-T-366: Dosimetric Parameters Enhancement of 120-Leaf Millennium MLC Using EGSnrc and IAEA Phase-Space Data

Energy Technology Data Exchange (ETDEWEB)

Haddad, K; Alopoor, H [Shiraz University, Shiraz, I.R. Iran (Iran, Islamic Republic of)

2016-06-15

Purpose: Recently, the multileaf collimators (MLC) have become an important part of any LINAC collimation systems because they reduce the treatment planning time and improves the conformity. Important factors that affects the MLCs collimation performance are leaves material composition and their thickness. In this study, we investigate the main dosimetric parameters of 120-leaf Millennium MLC including dose in the buildup point, physical penumbra as well as average and end leaf leakages. Effects of the leaves geometry and density on these parameters are evaluated Methods: From EGSnrc Monte Carlo code, BEAMnrc and DOSXYZnrc modules are used to evaluate the dosimetric parameters of a water phantom exposed to a Varian xi for 100cm SSD. Using IAEA phasespace data just above MLC (Z=46cm) and BEAMnrc, for the modified 120-leaf Millennium MLC a new phase space data at Z=52cm is produces. The MLC is modified both in leaf thickness and material composition. EGSgui code generates 521ICRU library for tungsten alloys. DOSXYZnrc with the new phase space evaluates the dose distribution in a water phantom of 60×60×20 cm3 with voxel size of 4×4×2 mm3. Using DOSXYZnrc dose distributions for open beam and closed beam as well as the leakages definition, end leakage, average leakage and physical penumbra are evaluated. Results: A new MLC with improved dosimetric parameters is proposed. The physical penumbra for proposed MLC is 4.7mm compared to 5.16 mm for Millennium. Average leakage in our design is reduced to 1.16% compared to 1.73% for Millennium, the end leaf leakage suggested design is also reduced to 4.86% compared to 7.26% of Millennium. Conclusion: The results show that the proposed MLC with enhanced dosimetric parameters could improve the conformity of treatment planning.

SU-E-T-471: Small Field Jaw/MLC Reference Data

International Nuclear Information System (INIS)

Kerns, J; Alvarez, P; Followill, D; Lowenstein, J; Molineu, A; Summers, P; Kry, S

2014-01-01

Purpose: In recent years the need for small field data of MLCs has increased due to the use of intensity-modulated radiation (IMRT), but moreover the use of stereotactic body radiation (SBRT) has increased, which uses not simply small field sizes, but small jaw and field sizes together. Having reference data for these small fields that is reliable would be invaluable to the physics community. Our study has gathered these values and the data distributions from the Radiological Physics Center's (RPC) site visits between 1990 and the present. Methods: For all measurements, the RPC used a 25 × 25 × 25cm water phantom placed at 100cm SSD. All measurements were made with an Exradin A16 cylindrical ion chamber at an effective depth of 10 cm. A total of 42 Varian machine measurements were used to compose the data for a 6 MV beam and 5 TrueBeam 6 MV flattening filter free (FFF) beams were used for FFF data. Results: Jaw/MLC fields were measured for both 6 MV and 6 MF FFF beams with the jaws and MLCs both at the following field sizes: 6×6, 4×4, 3×3, and 2×2cm. Measurements were normalized to the 10×10 field readings (defined by the jaws and MLC). Spread in the data was minimal and demonstrates a high level of accuracy of acquired data. Conclusion: Small field Jaw/MLC reference data for Varian 6MV and 6 MV FFF beams has been analyzed and presented here, composed of the aggregation of numerous RPC site visits. Obtaining reliable small field data remains difficult, however the RPC has collected high fidelity small field Jaw/MLC data. The data are presented as a reference along with their distributions, in such a way that the physicist can act based upon their own desired agreement with the reference data

Leaf transmission reduction using moving jaws for dynamic MLC IMRT

International Nuclear Information System (INIS)

Schmidhalter, D.; Fix, M. K.; Niederer, P.; Mini, R.; Manser, P.

2007-01-01

The aim of this work is to investigate to what extent it is possible to use the secondary collimator jaws to reduce the transmitted radiation through the multileaf collimator (MLC) during an intensity modulated radiation therapy (IMRT). A method is developed and introduced where the jaws follow the open window of the MLC dynamically (dJAW method). With the aid of three academic cases (Closed MLC, Sliding-gap, and Chair) and two clinical cases (prostate and head and neck) the feasibility of the dJAW method and the influence of this method on the applied dose distributions are investigated. For this purpose the treatment planning system Eclipse and the Research-Toolbox were used as well as measurements within a solid water phantom were performed. The transmitted radiation through the closed MLC leads to an inhomogeneous dose distribution. In this case, the measured dose within a plane perpendicular to the central axis differs up to 40% (referring to the maximum dose within this plane) for 6 and 15 MV. The calculated dose with Eclipse is clearly more homogeneous. For the Sliding-gap case this difference is still up to 9%. Among other things, these differences depend on the depth of the measurement within the solid water phantom and on the application method. In the Chair case, the dose in regions where no dose is desired is locally reduced by up to 50% using the dJAW method instead of the conventional method. The dose inside the chair-shaped region decreased up to 4% if the same number of monitor units (MU) as for the conventional method was applied. The undesired dose in the volume body minus the planning target volume in the clinical cases prostate and head and neck decreased up to 1.8% and 1.5%, while the number of the applied MU increased up to 3.1% and 2.8%, respectively. The new dJAW method has the potential to enhance the optimization of the conventional IMRT to a further step

Intraoperative use of ultrasonography by small subcortical lesions

International Nuclear Information System (INIS)

Kondoff, Sl.; Gabrovski, St.; Krustev, E.; Poptodorov, G.; Gabrovski, N.; Uzunov, K.

2004-01-01

The aim of this study is to present the possibilities for use of intraoperative ultrasound (US) diagnostics as a method of image guided surgical navigation in neurosurgery. During an US scan of normal and pathologically changed tissues as well as volume taking lesion images are received in real time intraoperative display allowing dynamic control of the surgical radicalism and at the same time minimal invasiveness to the neural structures. Intraoperative ultrasound with real-time display characteristics finds a very wide application: subcortical and deeply localized tumour lesions, haematomas, large and giant aneurysms, arteriovenous (AV) malformations, spinal tumours and cysts. The real time dynamic scan is based on the B-mod. This method is founded on the US characteristic of reflecting in a different manner at the borderline of two mediums with different density as well as tissues with various physical and chemical characteristics. The reflection is partially absorbed depending on the acoustic impedance of the biologic field. We use a LOGIC200PRO unit with two probes I-type and T-type having a 'wedge of space' - 35 mm and working frequencies of 6 MHz and 7 MHz appropriate for visualizing lesions at a depth of 25 to 60 mm.The advantages of the Intraoperative US diagnostics are: non-invasiveness; real time display - i.e. presents the imminent intraoperative changes; it is a good alternative to other image-guided technologies; accessible price of the US unit

Post-traumatic cysts and cyst-like lesions of bone

International Nuclear Information System (INIS)

Moore, T.E.; Travis, R.C.; Allen, B.C.; King, A.R.

1989-01-01

We describe two patients with cyst-like lesions of bone that developed at sites of healed or healing fractures. One case showed histological features of a unicameral bone cyst, which, to the best of our knowledge, is a previously unreported finding in a post-traumatic cyst. It is suggested that there are two principal clinical and radiological types of post-traumatic cyst, of which each of our cases represents an example: (1) asymtompatic transient cortical lesions, found only in children, and (2) more central expanding lesions, found in a wider age group and associated with pain, swelling, and pathological fractures. (orig.)

Post-traumatic cysts and cyst-like lesions of bone

Energy Technology Data Exchange (ETDEWEB)

Moore, T.E.; Travis, R.C.; Allen, B.C.; King, A.R.

1989-04-01

We describe two patients with cyst-like lesions of bone that developed at sites of healed or healing fractures. One case showed histological features of a unicameral bone cyst, which, to the best of our knowledge, is a previously unreported finding in a post-traumatic cyst. It is suggested that there are two principal clinical and radiological types of post-traumatic cyst, of which each of our cases represents an example: (1) asymtompatic transient cortical lesions, found only in children, and (2) more central expanding lesions, found in a wider age group and associated with pain, swelling, and pathological fractures. (orig.).

Effect of MLC leaf position, collimator rotation angle, and gantry rotation angle errors on intensity-modulated radiotherapy plans for nasopharyngeal carcinoma

Energy Technology Data Exchange (ETDEWEB)

Bai, Sen; Li, Guangjun; Wang, Maojie; Jiang, Qinfeng; Zhang, Yingjie [State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan (China); Wei, Yuquan, E-mail: yuquawei@vip.sina.com [State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan (China)

2013-07-01

The purpose of this study was to investigate the effect of multileaf collimator (MLC) leaf position, collimator rotation angle, and accelerator gantry rotation angle errors on intensity-modulated radiotherapy plans for nasopharyngeal carcinoma. To compare dosimetric differences between the simulating plans and the clinical plans with evaluation parameters, 6 patients with nasopharyngeal carcinoma were selected for simulation of systematic and random MLC leaf position errors, collimator rotation angle errors, and accelerator gantry rotation angle errors. There was a high sensitivity to dose distribution for systematic MLC leaf position errors in response to field size. When the systematic MLC position errors were 0.5, 1, and 2 mm, respectively, the maximum values of the mean dose deviation, observed in parotid glands, were 4.63%, 8.69%, and 18.32%, respectively. The dosimetric effect was comparatively small for systematic MLC shift errors. For random MLC errors up to 2 mm and collimator and gantry rotation angle errors up to 0.5°, the dosimetric effect was negligible. We suggest that quality control be regularly conducted for MLC leaves, so as to ensure that systematic MLC leaf position errors are within 0.5 mm. Because the dosimetric effect of 0.5° collimator and gantry rotation angle errors is negligible, it can be concluded that setting a proper threshold for allowed errors of collimator and gantry rotation angle may increase treatment efficacy and reduce treatment time.

Quality assurance of MLC leaf position accuracy and relative dose effect at the MLC abutment region using an electronic portal imaging device

International Nuclear Information System (INIS)

Sumida, Iori; Yamaguchi, Hajime; Kizaki, Hisao; Koizumi, Masahiko; Ogata, Toshiyuki; Takahashi, Yutaka; Yoshioka, Yasuo

2012-01-01

We investigated an electronic portal image device (EPID)-based method to see whether it provides effective and accurate relative dose measurement at abutment leaves in terms of positional errors of the multi-leaf collimator (MLC) leaf position. A Siemens ONCOR machine was used. For the garden fence test, a rectangular field (0.2x20 cm) was sequentially irradiated 11 times at 2-cm intervals. Deviations from planned leaf positions were calculated. For the nongap test, relative doses at the MLC abutment region were evaluated by sequential irradiation of a rectangular field (2x20 cm) 10 times with a MLC separation of 2 cm without a leaf gap. The integral signal in a region of interest was set to position A (between leaves) and B (neighbor of A). A pixel value at position B was used as background and the pixel ratio (A/Bx100) was calculated. Both tests were performed at four gantry angles (0, 90, 180 and 270deg) four times over 1 month. For the nongap test the difference in pixel ratio between the first and last period was calculated. Regarding results, average deviations from planned positions with the garden fence test were within 0.5 mm at all gantry angles, and at gantry angles of 90 and 270deg tended to decrease gradually over the month. For the nongap test, pixel ratio tended to increase gradually in all leaves, leading to a decrease in relative doses at abutment regions. This phenomenon was affected by both gravity arising from the gantry angle, and the hardware-associated contraction of field size with this type of machine. (author)

Bacteria associated with cysts of the soybean cyst nematode (Heterodera glycines).

Science.gov (United States)

Nour, Sarah M; Lawrence, John R; Zhu, Hong; Swerhone, George D W; Welsh, Martha; Welacky, Tom W; Topp, Edward

2003-01-01

The soybean cyst nematode (SCN), Heterodera glycines, causes economically significant damage to soybeans (Glycine max) in many parts of the world. The cysts of this nematode can remain quiescent in soils for many years as a reservoir of infection for future crops. To investigate bacterial communities associated with SCN cysts, cysts were obtained from eight SCN-infested farms in southern Ontario, Canada, and analyzed by culture-dependent and -independent means. Confocal laser scanning microscopy observations of cyst contents revealed a microbial flora located on the cyst exterior, within a polymer plug region and within the cyst. Microscopic counts using 5-(4,6-dichlorotriazine-2-yl)aminofluorescein staining and in situ hybridization (EUB 338) indicated that the cysts contained (2.6 +/- 0.5) x 10(5) bacteria (mean +/- standard deviation) with various cellular morphologies. Filamentous fungi were also observed. Live-dead staining indicated that the majority of cyst bacteria were viable. The probe Nile red also bound to the interior polymer, indicating that it is lipid rich in nature. Bacterial community profiles determined by denaturing gradient gel electrophoresis analysis were simple in composition. Bands shared by all eight samples included the actinobacterium genera Actinomadura and STREPTOMYCES: A collection of 290 bacteria were obtained by plating macerated surface-sterilized cysts onto nutrient broth yeast extract agar or on actinomycete medium. These were clustered into groups of siblings by repetitive extragenic palindromic PCR fingerprinting, and representative isolates were tentatively identified on the basis of 16S rRNA gene sequence. Thirty phylotypes were detected, with the collection dominated by Lysobacter and Variovorax spp. This study has revealed the cysts of this important plant pathogen to be rich in a variety of bacteria, some of which could presumably play a role in the ecology of SCN or have potential as biocontrol agents.

An EPID response calculation algorithm using spatial beam characteristics of primary, head scattered and MLC transmitted radiation

International Nuclear Information System (INIS)

Rosca, Florin; Zygmanski, Piotr

2008-01-01

We have developed an independent algorithm for the prediction of electronic portal imaging device (EPID) response. The algorithm uses a set of images [open beam, closed multileaf collimator (MLC), various fence and modified sweeping gap patterns] to separately characterize the primary and head-scatter contributions to EPID response. It also characterizes the relevant dosimetric properties of the MLC: Transmission, dosimetric gap, MLC scatter [P. Zygmansky et al., J. Appl. Clin. Med. Phys. 8(4) (2007)], inter-leaf leakage, and tongue and groove [F. Lorenz et al., Phys. Med. Biol. 52, 5985-5999 (2007)]. The primary radiation is modeled with a single Gaussian distribution defined at the target position, while the head-scatter radiation is modeled with a triple Gaussian distribution defined downstream of the target. The distances between the target and the head-scatter source, jaws, and MLC are model parameters. The scatter associated with the EPID is implicit in the model. Open beam images are predicted to within 1% of the maximum value across the image. Other MLC test patterns and intensity-modulated radiation therapy fluences are predicted to within 1.5% of the maximum value. The presented method was applied to the Varian aS500 EPID but is designed to work with any planar detector with sufficient spatial resolution

Periorbital dermoid cyst

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Nigwekar Shubhangi P, Gupte Chaitanya P, Chaudhari Sagar V, Kharche Prajakta S

2014-07-01

Full Text Available Dermoid cysts are a developmental benign choristomas, which are congenital lesions representing normal tissue/s in an abnormal location. These consist of ectodermal and mesodermal elements, lined with epithelium and contain hair with other skin structures. Periorbital dermoid cyst is commonly located at lateral one third of the eyebrow. It is asymptomatic however school going child suffers from social stigma. So its surgical excision for cosmetic purpose becomes necessary. Excision also prevents bony remoulding and recurrent inflammatory responses due to leakage of cyst contents. In this article we are presenting a six years old male child having periorbital dermoid in lateral right eyebrow. The intact dermoid cyst was excised surgically and sent for histopathological examination, which confirmed the diagnosis of dermoid cyst. We highlight the merits of early surgical intervention, even in an asymptomatic periorbital dermoid cyst.

Measurement for the MLC leaf velocity profile by considering the leaf leakage using a radiographic film

International Nuclear Information System (INIS)

Chow, James C L; Grigorov, Grigor N

2006-01-01

A method to measure the velocity profile of a multi-leaf collimator (MLC) leaf along its travel range using a radiographic film is reported by considering the intra-leaf leakage. A specific dynamic MLC field with leaves travelling from the field edge to the isocentre line was designed. The field was used to expose a radiographic film, which was then scanned, and the dose profile along the horizontal leaf axis was measured. The velocity at a sampling point on the film can be calculated by considering the horizontal distance between the sampling point and the isocentre line, dose at the sampling point, dose rate of the linear accelerator, the total leaf travel time from the field edge to isocentre line and the pre-measured dose rate of leaf leakage. With the leaf velocities and velocity profiles for all MLC leaves measured routinely, a comprehensive and simple QA for the MLC can be set up to test the consistency of the leaf velocity performance which is essential to the IMRT delivery using a sliding window technique. (note)

Expression of Ki-67 in odontogenic cysts: A comparative study between odontogenic keratocysts, radicular cysts and dentigerous cysts.

Science.gov (United States)

Modi, Tapan G; Chalishazar, Monali; Kumar, Malay

2018-01-01

Odontogenic cysts are the most common cysts of the jaws and are formed from the remnants of the odontogenic apparatus. Among these odontogenic cysts, radicular cysts (RCs) (about 60% of all diagnosed jaw cysts), dentigerous cysts (DCs) (16.6% of all jaw cysts) and odontogenic keratocysts (OKCs) (11.2% of all developmental odontogenic cysts) are the most common. The behavior of any lesion is generally reflected by its growth potential. Growth potential is determined by measuring the cell proliferative activity. The cell proliferative activity is measured by various methods among which immunohistochemistry (IHC) is the commonly used technique. Most of the IHC studies on cell proliferation have been based on antibodies such as Ki-67 and proliferating cell nuclear antigen. In the present study, the total sample size comprised of 45 cases of odontogenic cysts, with 15 cases each of OKC, RC and DC. Here, an attempt is made to study immunohistochemical (streptavidin-biotin detection system HRP-DAB) method to assess the expression of Ki-67 in different layers of the epithelial lining of OKCs, RCs and DCs. Ki-67 positive cells were highest in epithelium of OKC as compared to DC and RC. The increased Ki-67 labeling index and its expression in suprabasal cell layers of epithelial lining in OKC and its correlation with suprabasal cell layers of epithelial lining in DC and RC could contribute toward its clinically aggressive behavior. OKC is of more significance to the oral pathologist and oral surgeon because of its specific histopathological features, high recurrence rate and aggressive behavior.

Simple Kidney Cysts

Science.gov (United States)

... Solitary Kidney Your Kidneys & How They Work Simple Kidney Cysts What are simple kidney cysts? Simple kidney cysts are abnormal, fluid-filled ... that form in the kidneys. What are the kidneys and what do they do? The kidneys are ...

Independent dose calculation of the Tps Iplan in radiotherapy conformed with MLC

International Nuclear Information System (INIS)

Adrada, A.; Tello, Z.; Medina, L.; Garrigo, E.; Venencia, D.

2014-08-01

The systems utilization of independent dose calculation in three dimensional-Conformal Radiation Therapy (3D-Crt) treatments allows a direct verification of the treatments times. The utilization of these systems allows diminishing the probability of errors occurrence generated by the treatment planning system (Tps), allowing a detailed analysis of the dose to delivering and review of the normalization point (Np) or prescription. The independent dose calculation is realized across the knowledge of dosimetric parameters of the treatment machine and particular characteristics of every individual field. The aim of this work is develops a calculation system of punctual doses for isocentric fields conformed with multi-leaf collimation systems (MLC), where the dose calculation is in conformity with the suggested ones by ICRU Report No. 42, 1987. Calculation software was realized in C ++ under a free platform of programming (Code::Blocks). The system uses files in format Rtp, exported from the Tps to systems of record and verification (Lantis). This file contains detailed information of the dose, Um, position of the MLC sheets and collimators for every field of treatment. The size of equivalent field is obtained from the positions of every sheet; the effective depth of calculation can be introduced from the dosimetric report of the Tps or automatically from the DFS of the field. The 3D coordinates of the isocenter and the Np for the treatment plan must be introduced manually. From this information the system looks the dosimetric parameters and calculates the Um. The calculations were realized in two accelerators a NOVALIS Tx (Varian) with 120 sheets of high definition (hd-MLC) and a PRIMUS Optifocus (Siemens) with 82 sheets. 705 patients were analyzed for a total of 1082, in plans made for both equipment s, the average uncertainty with regard to the calculation of the Tps is-0.43% ± 2.42% in a range between [-7.90 %, 7.50 %]. The major uncertainty was in Np near of the

SU-F-T-429: Craniospinal Irradiation by VMAT Technique: Impact of FFF Beam and High Resolution MLC On Plan Quality

Energy Technology Data Exchange (ETDEWEB)

Ganesh, T; Sarkar, B; Munshi, A; Mohanti, B [Fortis Memorial Research Institute, Gurgaon, Haryana (India)

2016-06-15

Purpose: Objective of this study was to evaluate the impact of using flattening filter free (FFF) beam with 0.5 cm multileaf collimator (MLC) leaves over conventional flattened beam with 1 cm leaf width MLC on the treatment plan quality in cranio-spinal irradiation (CSI). Methods: For five medulloblastoma cases (3 males and 2 females), who were previously treated by volumetric modulated arc therapy (VMAT) technique using conventional flattened beam shaped by 1 cm width MLC leaves, four test plans were generated and compared against the delivered plan. These retrospective plans consisted of four different combinations of flattened and FFF beams from Elekta’s Agility treatment head with 0.5 cm width MLC leaves. Sparing of organs at risks (OAR) in terms of dose to 5%, 50%, 75% and 90% volumes, mean and maximum dose were evaluated. Results: All plans satisfied the planning objective of covering 95% of PTV by at least 95% of prescription dose. Marginal variation of dose spillage was observed between different VMAT plans at very low dose range (1–5 Gy). Variation in dose statistics for PTVs and OARs were within 1% or 1 Gy. Amongst the five plans, the plan with flattened beam with 1 cm MLC had the highest number of MUs, 2.13 times higher than the plan with Agility MLC with FFF beam that had the least number of MUs. No statistically significant difference (p≥0.05) was observed between the reference plan and the retrospectively generated plans in terms of PTV coverage, cold spot, hot spot and organ at risk doses. Conclusion: In the treatment of CSI cases by VMAT technique, FFF beams and/or finer width MLC did not exhibit advantage over the flattened beams or wider MLC in terms of plan quality except for reduction in MUs.

Management of ovarian cysts

DEFF Research Database (Denmark)

Knudsen, Ulla Breth; Tabor, Ann; Mosgaard, Berit Jul

2004-01-01

BACKGROUND: The treatment of an ovarian cyst relies on its nature, and accurate preoperative discrimination of benign and malignant cysts is therefore of crucial importance. This study was undertaken to review the literature concerning the preoperative diagnosis and treatment of ovarian cysts....... METHODS: Articles concerning ovarian cysts from a medline literature search during the period 1985-2003 were included in addition to articles found as references in the initial publications. RESULTS: Different methods for discriminating between benign and malignant ovarian cysts are discussed....... The diagnosis and the treatment are assessed in relation to age, menopausal status, pregnancy, and whether the cyst is presumed to be benign or malignant. In general, expectant management is the choice in premenopausal and pregnant women with non-suspicious cysts and normal levels of CA-125. In postmenopausal...

SU-E-T-479: IMRT Plan Recalculation in Patient Based On Dynalog Data and the Effect of a Single Failing MLC Motor

International Nuclear Information System (INIS)

Morcos, M; Mitrou, E

2015-01-01

Purpose: Using Linac dynamic logs (Dynalogs) we evaluate the impact of a single failing MLC motor on the deliverability of an IMRT plan by assessing the recalculated dose volume histograms (DVHs) taking the delivered MLC positions and beam hold-offs into consideration. Methods: This is a retrospective study based on a deteriorating MLC motor (leaf 36B) which was observed to be failing via Dynalog analysis. To investigate further, Eclipse-importable MLC files were generated from Dynalogs to recalculate the actual delivered dose and to assess the clinical impact through DVHs. All deliveries were performed on a Varian 21EX linear accelerator equipped with Millennium-120 MLC. The analysis of Dynalog files and subsequent conversion to Eclipse-importable MLC files were all performed by in-house programming in Python. Effects on plan DVH are presented in the following section on a particular brain-IMRT plan which was delivered with a failing MLC motor which was then replaced. Results: Global max dose increased by 13.5%, max dose to the brainstem PRV increased by 8.2%, max dose to the optic chiasm increased by 7.6%, max dose to optic nerve increased by 8.8% and the mean dose to the PTV increased by 7.9% when comparing the original plan to the fraction with the failing MLC motor. The reason the dose increased was due to the failure being on the B-bank which is the lagging side on a sliding window delivery, therefore any failures on this side will cause an over-irradiation as the B-bank leaves struggles to keep the window from growing. Conclusion: Our findings suggest that a single failing MLC motor may jeopardize the entire delivery. This may be due to the bad MLC motor drawing too much current causing all MLCs on the same bank to underperform. This hypothesis will be investigated in a future study

SU-E-T-479: IMRT Plan Recalculation in Patient Based On Dynalog Data and the Effect of a Single Failing MLC Motor

Energy Technology Data Exchange (ETDEWEB)

Morcos, M [Vantage Oncology, San Bernardino, CA (United States); Mitrou, E [Centre Hospitalier de l’Universite de Montreal, Montreal, QC (Canada)

2015-06-15

Purpose: Using Linac dynamic logs (Dynalogs) we evaluate the impact of a single failing MLC motor on the deliverability of an IMRT plan by assessing the recalculated dose volume histograms (DVHs) taking the delivered MLC positions and beam hold-offs into consideration. Methods: This is a retrospective study based on a deteriorating MLC motor (leaf 36B) which was observed to be failing via Dynalog analysis. To investigate further, Eclipse-importable MLC files were generated from Dynalogs to recalculate the actual delivered dose and to assess the clinical impact through DVHs. All deliveries were performed on a Varian 21EX linear accelerator equipped with Millennium-120 MLC. The analysis of Dynalog files and subsequent conversion to Eclipse-importable MLC files were all performed by in-house programming in Python. Effects on plan DVH are presented in the following section on a particular brain-IMRT plan which was delivered with a failing MLC motor which was then replaced. Results: Global max dose increased by 13.5%, max dose to the brainstem PRV increased by 8.2%, max dose to the optic chiasm increased by 7.6%, max dose to optic nerve increased by 8.8% and the mean dose to the PTV increased by 7.9% when comparing the original plan to the fraction with the failing MLC motor. The reason the dose increased was due to the failure being on the B-bank which is the lagging side on a sliding window delivery, therefore any failures on this side will cause an over-irradiation as the B-bank leaves struggles to keep the window from growing. Conclusion: Our findings suggest that a single failing MLC motor may jeopardize the entire delivery. This may be due to the bad MLC motor drawing too much current causing all MLCs on the same bank to underperform. This hypothesis will be investigated in a future study.

Calcified adrenal cyst

Energy Technology Data Exchange (ETDEWEB)

Kim, Chung Kyu; Choi, Byung Sook [Yonsei University College of Medicine, Seoul (Korea, Republic of)

1970-10-15

Calcified hemorrhagic adrenal cysts are rather rare and unusual pathologic entity. Especially, the peripheral curvilinear calcification on roentgenogram is fairly characteristic picture of the cysts. Recently, we have experienced in Severance Hospital one of the classical cases of the benign calcified adrenal cyst in 35 year old white mail patient who has had vague abdominal pain and palpable mass in right abdomen. It has been reviewed several reports for adrenal cysts and hoped that this report may call additional attention of radiological diagnosis on this unusual disease.

Splenic epithelial cyst

International Nuclear Information System (INIS)

Yousuf, M.; Jalali, U.

2011-01-01

Cysts of spleen are rare entities. Congenital splenic cysts are even more uncommon comprising of only 10% of benign non-parasitic cysts. We report a case of 22 years old female who presented with history of 2 years abdominal pain and gradual distension. Ultrasound and computed tomography (CT) both were suggestive of splenic cyst. Laboratory tests show thrombocytopenia with platelets count of 97000 per cubic millimeter and anemia with hemoglobin 8.7 gram per deciliter. Serological tests were negative for parasitic infection. Splenectomy was done and the weight of the spleen was found to be 1.5 kilogram. Histopathological findings are consistent with splenic epithelial cyst. The aetiology, diagnostic modalities and treatment options are discussed in the case report. (author)

Tail gut cyst.

Science.gov (United States)

Rao, G Mallikarjuna; Haricharan, P; Ramanujacharyulu, S; Reddy, K Lakshmi

2002-01-01

The tail gut is a blind extension of the hindgut into the tail fold just distal to the cloacal membrane. Remnants of this structure may form tail gut cyst. We report a 14-year-old girl with tail gut cyst that presented as acute abdomen. The patient recovered after cyst excision.

Vaginal cysts

Science.gov (United States)

... this page: //medlineplus.gov/ency/article/001509.htm Vaginal cysts To use the sharing features on this ... with air, fluid, pus, or other material. A vaginal cyst occurs on or under the lining of ...

Odontogenic cysts in three dogs: one odontogenic keratocyst and two dentigerous cysts.

Science.gov (United States)

Watanabe, Kazuhiro; Kadosawa, Tsuyoshi; Ishiguro, Taketo; Takagi, Satoshi; Ochiai, Kenji; Kimura, Takashi; Okumura, Masahiro; Fujinaga, Toru

2004-09-01

Odontogenic cysts, which showed cystic radiolucency in the jaw bone by radiographic examination and computed tomography, were enucleated by operation in 3 dogs. One dog had a odontogenic keratocyst in the incisive bone of the right maxilla and another 2 cases revealed dentigerous cysts in the mandible. These cyst walls were enucleated or transpired by semiconductor laser. Afterwards, osteogenesis was confirmed at the defective part of jaw bone by extirpation of the cyst in all cases, and no recurrence has been noted in any cases. Odontogenic cyst is a disease which should be treated by surgical extirpation or transpiration.

Odontogenic cysts in three dogs: One odontogenic keratocyst and two dentigerous cysts

International Nuclear Information System (INIS)

Watanabe, K.; Kadosawa, T.; Ishiguro, T.; Takagi, S.; Ochiai, K.; Kimura, T.; Okumura, M.; Fujinaga, T.

2004-01-01

Odontogenic cysts, which showed cystic radiolucency in the jaw bone by radiographic examination and computed tomography, were enucleated by operation in 3 dogs. One dog had a odontogenic keratocyst in the incisive bone of the right maxilla and another 2 cases revealed dentigerous cysts in the mandible. These cyst walls were enucleated or transpired by semiconductor laser. Afterwards, osteogenesis was confirmed at the defective pan of jaw bone by extirpation of the cyst in all cases, and no recurrence has been noted in any cases. Odontogenic cyst is a disease which should be treated by surgical extirpation or transpiration

Primary Peritoneal Hydatid Cyst Presenting as Ovarian Cyst Torsion: A Rare Case Report

OpenAIRE

Gandhiraman, Kavitha; Balakrishnan, Renukadevi; Ramamoorthy, Rathna; Rajeshwari, Raja

2015-01-01

Hydatid cyst disease is a zoonotic disease caused by Echinococcus granulosus, E.multilocularis or E.Vogli. The most common primary site is liver (75%) followed by lungs (5-15%) and other organs constitute 10-20%. Peritoneal hydatid cysts are very rare especially primary peritoneal hydatid. Secondary peritoneal hydatid cysts are relatively common, which usually occurs due to rupture of primary hepatic hydatid cyst. We present a rare case of large primary peritoneal hydatid cyst misdiagnosed as...

SU-E-T-506: Dosimetric Verification of Photon MLC Delivered Electron Fields for Implementing MERT On An Artiste Linac

International Nuclear Information System (INIS)

Jin, L; Eldib, A; Li, J; Wang, L; Ma, C; Fan, J

2014-01-01

Purpose: To verify the dose accuracy of photon MLC delivered electron fields for implementing energy-intensity modulated electron radiotherapy (MERT) on an Artiste linac. Methods: It was proposed to deliver MERT on an Artiste linac at a short SSD (60 cm) to reduce beam penumbra caused by electron scatters. An in-house developed Monte Carlo (MC)-based dose calculation/optimization planning code was used for treatment planning. Our previous study showed that the measured dose distribution of a breast plan showed good agreement with the calculations in low-medium dose regions while the differences in high dose regions were outstanding. A continuous work found that the discrepancy is mainly caused by improper modeling in MC for the single focused MLC in the Artiste which was simplified as double focused in the previous MC simulations. With this remodeled MLC in the calculations, an energy-intensity modulated electron plan using 6, 9, 12 and 15 MeV was generated for a breast treatment on a breast phantom at a 60 cm SSD and recalculated regarding a solid water phantom. For a test study, four of MLC segments (each with a different energy) generated in the plan were delivered to the phantom and a film measurement was performed at the depth of 2 cm. The measured 2D dose distribution was then compared with calculations. Results: For composite doses of the four segments, measured 2D dose distributions overall agree well with the calculations (3mm/3%) in most area. The separate measurement for a single MLC segment for each of energies also showed the consistence with the calculations. Conclusion: After remodeling MLC in the MC calculations, the measured dose distribution for a subset of MLC segments from a MERT plan showed good agreement. Further detailed verification for the full plan will be the work in the next step

Comparison of conventional inserts and an add-on electron MLC for chest wall irradiation of left-sided breast cancer

International Nuclear Information System (INIS)

Vatanen, Tero; Lahtinen, Tapani; Traneus, Erik

2009-01-01

Background. Collimation of irregularly shaped clinical electron beams is currently based on electron inserts made of low melting point alloys. The present investigation compares a conventional electron applicator with insert and add-on eMLC-based dose distributions in the postoperative chest wall irradiation of left-sided breast cancer. Material and methods. Voxel Monte Carlo++ (VMC++) calculated dose distributions related to electron fields were compared with 10 left-sided breast cancer patients after radical mastectomy. The prescription dose was 50 Gy at a build-up maximum. The same dose was prescribed for the ipsilateral axillary, parasternal and supraclavicular lymph nodes that were treated with photons and calculated with a pencil beam algorithm. The insert beams were shaped with 1.5 cm thick Wood's metal electron inserts in an electron applicator of a Varian 2100 C/D linac. Doses for the eMLC-shaped beams were calculated for an eMLC prototype with 2 cm thick and 5 mm wide steel leaves. The same collimator-to-surface distance (CSD) of 5.8 cm was used for both collimators. Results. The mean PTV dose was slightly higher for the eMLC plans (50.7 vs 49.5 Gy, p<0.001, respectively). The maximum doses assessed by D5% for the eMLC and insert were 60.9 and 59.1 Gy (p<0.001). The difference was due to the slightly higher doses near the field edges for the eMLC. The left lung V20 volumes were 34.5% and 34.0% (p<0.001). There was only a marginal difference in heart doses. Discussion: Despite a slight increase of maximum dose in PTV the add-on electron MLC for chest wall irradiation results in practically no differences in dose distributions compared with the present insert-based collimation

Nonsurgical root canal therapy of large cyst-like inflammatory periapical lesions and inflammatory apical cysts.

Science.gov (United States)

Lin, Louis M; Ricucci, Domenico; Lin, Jarshen; Rosenberg, Paul A

2009-05-01

It is a general belief that large cyst-like periapical lesions and apical true cysts caused by root canal infection are less likely to heal after nonsurgical root canal therapy. Nevertheless, there is no direct evidence to support this assumption. A large cyst-like periapical lesion or an apical true cyst is formed within an area of apical periodontitis and cannot form by itself. Therefore, both large cyst-like periapical lesions and apical true cysts are of inflammatory and not of neoplastic origin. Apical periodontitis lesions, regardless of whether they are granulomas, abscesses, or cysts, fail to heal after nonsurgical root canal therapy for the same reason, intraradicular and/or extraradicular infection. If the microbial etiology of large cyst-like periapical lesions and inflammatory apical true cysts in the root canal is removed by nonsurgical root canal therapy, the lesions might regress by the mechanism of apoptosis in a manner similar to the resolution of inflammatory apical pocket cysts. To achieve satisfactory periapical wound healing, surgical removal of an apical true cyst must include elimination of root canal infection.

Keratinizing dentigerous cyst

Science.gov (United States)

Sivasankar, Vaishnavi; Ranganathan, Kannan; Praveen, B

2014-01-01

Keratinizing dentigerous cyst is a rare entity. This article reports a case of keratinizing dentigerous cyst associated with an impacted mandibular canine. Clinical and radiological features, cone-beam computed tomography findings and histological features of the case are reported along with a discussion on keratinizing odontogenic cysts and the need for follow-up. PMID:24808713

Keratinizing dentigerous cyst

Directory of Open Access Journals (Sweden)

Vaishnavi Sivasankar

2014-01-01

Full Text Available Keratinizing dentigerous cyst is a rare entity. This article reports a case of keratinizing dentigerous cyst associated with an impacted mandibular canine. Clinical and radiological features, cone-beam computed tomography findings and histological features of the case are reported along with a discussion on keratinizing odontogenic cysts and the need for follow-up.

Submental epidermoid cysts in children.

Science.gov (United States)

Zielinski, Rafal; Zakrzewska, Anna

2015-01-01

Epidermoid cysts are lesions, which form as a result of implantation of the epidermis in the layers of the dermis or the mucous membrane. The lesions are rare in adults with 7% occurring in the head and neck area and most often located in the submental region. In children population submental epidermoid cysts are extremely rare. The differential diagnosis of the lesions is necessary as it affects the choice of treatment methods. Among the pathological conditions occurring in that region, salivary retention cyst (ranula), thyroglossal duct cyst, vascular lymphatic malformation (cystic hygroma), median neck cyst, lymphadenopathy, thyroid gland tumor, laryngeal cyst, epidermoid and dermoid cysts, submental abscess, sialolithiasis and salivary gland inflammation should be considered. The authors of the present report demonstrate two cases of submental epidermoid cysts in children. Differential diagnosis in case of suspected submental epidermoid cyst in a child with proposed clinical practice and literature review is provided.

Quantifying the gantry sag on linear accelerators and introducing an MLC-based compensation strategy

Energy Technology Data Exchange (ETDEWEB)

Du Weiliang; Gao Song; Wang Xiaochun; Kudchadker, Rajat J. [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States)

2012-04-15

Purpose: Gantry sag is one of the well-known sources of mechanical imperfections that compromise the spatial accuracy of radiation dose delivery. The objectives of this study were to quantify the gantry sag on multiple linear accelerators (linacs), to investigate a multileaf collimator (MLC)-based strategy to compensate for gantry sag, and to verify the gantry sag and its compensation with film measurements. Methods: The authors used the Winston-Lutz method to measure gantry sag on three Varian linacs. A ball bearing phantom was imaged with megavolt radiation fields at 10 deg. gantry angle intervals. The images recorded with an electronic portal imaging device were analyzed to derive the radiation isocenter and the gantry sag, that is, the superior-inferior wobble of the radiation field center, as a function of the gantry angle. The authors then attempted to compensate for the gantry sag by applying a gantry angle-specific correction to the MLC leaf positions. The gantry sag and its compensation were independently verified using film measurements. Results: Gantry sag was reproducible over a six-month measurement period. The maximum gantry sag was found to vary from 0.7 to 1.0 mm, depending on the linac and the collimator angle. The radiation field center moved inferiorly (i.e., away from the gantry) when the gantry was rotated from 0 deg. to 180 deg. After the MLC leaf position compensation was applied at 90 deg. collimator angle, the maximum gantry sag was reduced to <0.2 mm. The film measurements at gantry angles of 0 deg. and 180 deg. verified the inferior shift of the radiation fields and the effectiveness of MLC compensation. Conclusions: The results indicate that gantry sag on a linac can be quantitatively measured using a simple phantom and an electronic portal imaging device. Reduction of gantry sag is feasible by applying a gantry angle-specific correction to MLC leaf positions at 90 deg. collimator angle.

Fast leaf-fitting with generalized underdose/overdose constraints for real-time MLC tracking

Energy Technology Data Exchange (ETDEWEB)

Moore, Douglas, E-mail: douglas.moore@utsouthwestern.edu; Sawant, Amit [Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, Texas 75390 (United States); Ruan, Dan [Department of Radiation Oncology, University of California, Los Angeles, California 90095 (United States)

2016-01-15

Purpose: Real-time multileaf collimator (MLC) tracking is a promising approach to the management of intrafractional tumor motion during thoracic and abdominal radiotherapy. MLC tracking is typically performed in two steps: transforming a planned MLC aperture in response to patient motion and refitting the leaves to the newly generated aperture. One of the challenges of this approach is the inability to faithfully reproduce the desired motion-adapted aperture. This work presents an optimization-based framework with which to solve this leaf-fitting problem in real-time. Methods: This optimization framework is designed to facilitate the determination of leaf positions in real-time while accounting for the trade-off between coverage of the PTV and avoidance of organs at risk (OARs). Derived within this framework, an algorithm is presented that can account for general linear transformations of the planned MLC aperture, particularly 3D translations and in-plane rotations. This algorithm, together with algorithms presented in Sawant et al. [“Management of three-dimensional intrafraction motion through real-time DMLC tracking,” Med. Phys. 35, 2050–2061 (2008)] and Ruan and Keall [Presented at the 2011 IEEE Power Engineering and Automation Conference (PEAM) (2011) (unpublished)], was applied to apertures derived from eight lung intensity modulated radiotherapy plans subjected to six-degree-of-freedom motion traces acquired from lung cancer patients using the kilovoltage intrafraction monitoring system developed at the University of Sydney. A quality-of-fit metric was defined, and each algorithm was evaluated in terms of quality-of-fit and computation time. Results: This algorithm is shown to perform leaf-fittings of apertures, each with 80 leaf pairs, in 0.226 ms on average as compared to 0.082 and 64.2 ms for the algorithms of Sawant et al., Ruan, and Keall, respectively. The algorithm shows approximately 12% improvement in quality-of-fit over the Sawant et al

Fast leaf-fitting with generalized underdose/overdose constraints for real-time MLC tracking

International Nuclear Information System (INIS)

Moore, Douglas; Sawant, Amit; Ruan, Dan

2016-01-01

Purpose: Real-time multileaf collimator (MLC) tracking is a promising approach to the management of intrafractional tumor motion during thoracic and abdominal radiotherapy. MLC tracking is typically performed in two steps: transforming a planned MLC aperture in response to patient motion and refitting the leaves to the newly generated aperture. One of the challenges of this approach is the inability to faithfully reproduce the desired motion-adapted aperture. This work presents an optimization-based framework with which to solve this leaf-fitting problem in real-time. Methods: This optimization framework is designed to facilitate the determination of leaf positions in real-time while accounting for the trade-off between coverage of the PTV and avoidance of organs at risk (OARs). Derived within this framework, an algorithm is presented that can account for general linear transformations of the planned MLC aperture, particularly 3D translations and in-plane rotations. This algorithm, together with algorithms presented in Sawant et al. [“Management of three-dimensional intrafraction motion through real-time DMLC tracking,” Med. Phys. 35, 2050–2061 (2008)] and Ruan and Keall [Presented at the 2011 IEEE Power Engineering and Automation Conference (PEAM) (2011) (unpublished)], was applied to apertures derived from eight lung intensity modulated radiotherapy plans subjected to six-degree-of-freedom motion traces acquired from lung cancer patients using the kilovoltage intrafraction monitoring system developed at the University of Sydney. A quality-of-fit metric was defined, and each algorithm was evaluated in terms of quality-of-fit and computation time. Results: This algorithm is shown to perform leaf-fittings of apertures, each with 80 leaf pairs, in 0.226 ms on average as compared to 0.082 and 64.2 ms for the algorithms of Sawant et al., Ruan, and Keall, respectively. The algorithm shows approximately 12% improvement in quality-of-fit over the Sawant et al

MR imaging of simple bone cysts in children: not so simple

Energy Technology Data Exchange (ETDEWEB)

Margau, R. [Faculty of Medicine, University of Toronto, Toronto, ON (Canada); Babyn, P. [Department of Diagnostic Imaging, The Hospital for Sick Children, Toronto, ON (Canada); Cole, W.; Lee, F. [Division of Orthopaedic Surgery, Department of Surgery, The Hospital for Sick Children and University of Toronto, Toronto, ON (Canada); Smith, C. [Department of Pathology, The Hospital for Sick Children and University of Toronto, Toronto, ON (Canada)

2000-08-01

Objective. The unicameral bone cyst (UBC) is a common cystic bone lesion seen in children. We review and summarize its MR findings, focusing on their appearance following contrast enhancement, and correlating them to known histologic features of UBC. Subjects and methods. A retrospective review of 20 cases (13 boys, 7 girls; age range, 1-17 years; mean age, 8.9) diagnosed as UBC was conducted. Clinical histories, radiographic and MR features, follow-up data, and available pathologic findings were noted. Results. At initial presentation 18 (90 %) of the patients with UBC had a history of acute or remote pathologic fracture. Cysts with history of fracture displayed heterogeneous fluid signals on T1- (n = 9, 50 %), and T2-weighted (n = 15, 83 %) MR images. Gadolinium-enhanced images were obtained in 15 of the 18 UBC cases with history of previous fracture. All showed enhancement with focal, thick peripheral, heterogeneous, or subcortical patterns. Focal nodules of homogeneous enhancement (diameter > 1 cm) within the UBC (n = 5) correlated with areas of ground-glass opacification on plain film. Other interesting MR features were fluid-fluid levels (n = 11), ''fallen-leaf'' sign (n = 1), soft-tissue changes (n = 2), and detection of septations not seen on plain film (n = 2). Conclusion. UBCs frequently appear complicated on MR imaging, with heterogeneous fluid signals and regions of nodular and thick peripheral enhancement related to previous pathologic fracture and early healing. (orig.)

MR imaging of simple bone cysts in children: not so simple

International Nuclear Information System (INIS)

Margau, R.; Babyn, P.; Cole, W.; Lee, F.; Smith, C.

2000-01-01

Objective. The unicameral bone cyst (UBC) is a common cystic bone lesion seen in children. We review and summarize its MR findings, focusing on their appearance following contrast enhancement, and correlating them to known histologic features of UBC. Subjects and methods. A retrospective review of 20 cases (13 boys, 7 girls; age range, 1-17 years; mean age, 8.9) diagnosed as UBC was conducted. Clinical histories, radiographic and MR features, follow-up data, and available pathologic findings were noted. Results. At initial presentation 18 (90 %) of the patients with UBC had a history of acute or remote pathologic fracture. Cysts with history of fracture displayed heterogeneous fluid signals on T1- (n = 9, 50 %), and T2-weighted (n = 15, 83 %) MR images. Gadolinium-enhanced images were obtained in 15 of the 18 UBC cases with history of previous fracture. All showed enhancement with focal, thick peripheral, heterogeneous, or subcortical patterns. Focal nodules of homogeneous enhancement (diameter > 1 cm) within the UBC (n = 5) correlated with areas of ground-glass opacification on plain film. Other interesting MR features were fluid-fluid levels (n = 11), ''fallen-leaf'' sign (n = 1), soft-tissue changes (n = 2), and detection of septations not seen on plain film (n = 2). Conclusion. UBCs frequently appear complicated on MR imaging, with heterogeneous fluid signals and regions of nodular and thick peripheral enhancement related to previous pathologic fracture and early healing. (orig.)

Implications of Subcortical structures in Aphasia.

Directory of Open Access Journals (Sweden)

Saleh Alamri

2015-04-01

Taken together, the results indicate that aphasia is a common outcome after a lesion to subcortical structures. Findings show that 110 out of 394 aphasic patients with lesion in the basal ganglia exhibited comprehension deficits, while 31 participants out of 288 with thalamic aphasia. Likewise, 129 aphasics of affected basal ganglia out of 394 had impaired naming, whereas 12 participants had impaired naming out of 288 individuals with thalamic aphasia. See figure 1. Figure 1: The percentage of language impairment in two sets of aphasic patients (the thalamus and the basal ganglia. Despite contradictory results and even cases of double dissociation (for an example of absence of language deficits in the event of thalamic lesions see Cappa et al., 1986, our literature review confirms the major role of subcortical structures in language processing.

Real-Time Dynamic MLC Tracking for Intensity Modulated Arc Therapy

DEFF Research Database (Denmark)

Falk, Marianne

Motion management of intra-fraction tumour motion during radiotherapy treatment can be a challenging task in order to achieve tumour control as well as minimizing the dose to the surrounding healthy tissue. Real-time dynamic multileaf collimator (MLC) tracking is a novel method for intra-fraction...

Primary Posterior Mediastinum Hydatid Cyst

International Nuclear Information System (INIS)

Ahmed, M.; Eid, A. F.; Sheikh, M. Y.; Yiannakou, N.

2014-01-01

Primary posterior mediastinal hydatid cyst is a serious health problem for the Mediterranean countries. We diagnosed a case of a 46-year-old female with a primary posterior mediastinum hydatid cyst on CT and MRI. It was provisionally identified as either a hydatid cyst or bronchogenic cyst or neuroenteric cyst. CT guided aspiration with 18 gauge needle confirmed as hydatid sand. This is very rare in this population but it should be kept in mind when one is looking at any cyst in the posterior mediastinum. (author)

Genetic influences on schizophrenia and subcortical brain volumes

DEFF Research Database (Denmark)

Franke, Barbara; Stein, Jason L; Ripke, Stephan

2016-01-01

and subcortical volume measures either at the level of common variant genetic architecture or for single genetic markers. These results provide a proof of concept (albeit based on a limited set of structural brain measures) and define a roadmap for future studies investigating the genetic covariance between...... genome-wide data to investigate genetic overlap. Here we integrated results from common variant studies of schizophrenia (33,636 cases, 43,008 controls) and volumes of several (mainly subcortical) brain structures (11,840 subjects). We did not find evidence of genetic overlap between schizophrenia risk...

21 CFR 882.5840 - Implanted intracerebral/subcortical stimulator for pain relief.

Science.gov (United States)

2010-04-01

... pain relief. 882.5840 Section 882.5840 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Devices § 882.5840 Implanted intracerebral/subcortical stimulator for pain relief. (a) Identification. An implanted intracerebral/subcortical stimulator for pain relief is a device that applies electrical current...

Congenital Hepatic Cyst

Directory of Open Access Journals (Sweden)

Aldo Recinos

2017-04-01

Full Text Available Congenital hepatic cyst is a rare and nonsymptomatic condition in infants and children. Its incidence is 2.5% in the postnatal life with a much lower incidence in the prenatal period. Incidental finding on antenatal imaging is the most common presentation. We present a case of a newborn in whom fetal ultrasound detected a cyst within the fetal liver. Postnatal imaging revealed a liver cyst in the right lobe of the liver, with no other intrahepatic structure affected. Liver function tests were abnormal, but the patient was asymptomatic. Posterior follow-up imaging showed a minor decrease in size. Management of congenital hepatic cyst is usually conservative, done with periodic ultrasound monitoring. However, surgical treatment is the mainstay of treatment when hydrops, progressive enlargement, hemorrhage, torsion, or compression of adjacent structures occurs. Malignant transformation can occur, but it is extremely rare. Partial or total removal of the cyst is the preferred treatment in neonates with a large lesion.

SU-G-JeP2-03: Automatic Quantification of MLC Positional Accuracy in An MRI Guided Radiotherapy System

International Nuclear Information System (INIS)

Li, X; Studenski, M; Yang, F; Dogan, N; Lamichhane, N; Padgett, K

2016-01-01

Purpose: MRI-guided-radiotherapy (MRIGRT) systems lack many features of traditional Linac based RT systems and specialized tests need to be developed to evaluate MLC performance. This work describes automatic tools for the analysis of positional accuracy of an MLC equipped MRIGRT system. Methods: This MLC analysis tool was developed for the MRIdian™ RT system which has three Co-60 equipped treatment heads each with a double focused MLC containing 30 leaf pairs, leaf thickness is 1.05cm defined at isocenter (SAD 105 cm). For MLC positional analysis a picket fence test was performed using a 25.4cm × 25.4cm Gafchromic™ RTQA2 film placed between 5cm solidwater and a 30cm × 30cm × 1cm jigwire phantom with seven embedded parallel metal strips 4cm apart. A plan was generated to deliver 2Gy per field and seven 23.1cm × 2cm fields centered over each wire in the phantom. For each leaf pair the center of the radiation profile was determined by fitting the horizontal profile with a Gaussian model and determining the center of the FWHM. This was compared with the metal strip location to determine any deviation. The following metrics were used to evaluate the deviations per gantry angle including maximum, minimum, mean, Kurtosis, and skewness. Results: The identified maximum/mean leaf deviations are, 1.32/0.55 mm for gantry 0°, 1.59/0.76 mm for gantry 90°, and 1.19/0.39 mm for gantry 270°. The percentage of leaf deviation less than 1mm are 90.0% at 0°, 74.6% at 90°, and 97.0% at 270°. Kurtosis/skewness of the leaf deviation are 2.41/0.14 at 0°, 2.53/0.23 at 90°, 3.33/0.83 at 270°, respectively. Conclusion: This work presents an automatic tool for evaluation of the MLC position accuracy of the MRIdian™ radiotherapy system which can be used to benchmark the performance of the MLC system for each treatment head and track the results longitudinally.

Efficacy and Safety of MLC601 in the Treatment of Mild Cognitive Impairment: A Pilot, Randomized, Double-Blind, Placebo-Controlled Study

Directory of Open Access Journals (Sweden)

Hossein Pakdaman

2017-05-01

Full Text Available Background and Aim: Mild cognitive impairment (MCI is characterized by declined cognitive function greater than that expected for a person’s age. The clinical significance of this condition is its possible progression to dementia. MLC601 is a natural neuroprotective medication that has shown promising effects in Alzheimer disease. Accordingly, we conducted this randomized, double-blind, placebo-controlled study to evaluate the efficacy and safety of MLC601 in MCI patients. Methods: Seventy-two patients with a diagnosis of MCI were recruited. The included participants were randomly assigned to groups to receive either MLC601 or placebo. An evaluation of global cognitive function was performed at baseline as well as at 3-month and 6-month follow-up visits. Global cognitive function was assessed by Mini-Mental State Examination (MMSE and Alzheimer’s Disease Assessment Scale-cognitive subscale (ADAS-cog scores. Efficacy was evaluated by comparing global function scores between the 2 groups during the study period. Safety assessment included adverse events (AEs and abnormal laboratory results. Results: Seventy patients completed the study, 34 in the MLC601 group and 36 in the placebo group. The mean changes (±SD in cognition scores over 6 months in the MLC601 group were –2.26 (±3.42 for the MMSE and 3.82 (±6.16 for the ADAS-cog; in the placebo group, they were –2.66 (±3.43 for the MMSE and 4.41 (±6.66 for the ADAS-cog. The cognition changes based on both MMSE and ADAS-cog scores were statistically significant between the placebo and the MLC601 group (p < 0.001. Only 5 patients (14.7% reported minor AEs in the MLC601 group, the most commonly reported of which were gastrointestinal, none of them leading to patient withdrawal. Conclusion: MLC601 has shown promising efficacy and acceptable AEs in MCI patients.

Validation of dynamic MLC-controller log files using a two-dimensional diode array

International Nuclear Information System (INIS)

Li, Jonathan G.; Dempsey, James F.; Ding Li; Liu, Chihray; Palta, Jatinder R.

2003-01-01

Intensity-modulated radiation therapy (IMRT) delivered with multi-leaf collimator (MLC) in the step-and-shoot mode uses multiple static MLC segments to achieve intensity modulation. For typical IMRT treatment plans, significant numbers of segments are delivered with monitor units (MUs) of much less than 10. Verification of the ability of the linear accelerator (linac) to deliver small MU segments accurately is an important step in the IMRT commissioning and quality assurance (QA) process. Recent studies have reported large discrepancies between the intended and delivered segment MUs. These discrepancies could potentially cause large errors in the delivered patient dose. We have undertaken a systematic study to evaluate the accuracy of the dynamic MLC log files, which are created automatically by our commercial MLC workstation after each delivery, in recording the fractional MU delivered in the step-and-shoot mode. Two linac models were evaluated with simple-geometry leaf sequences and delivered with different total MUs and different nominal dose rates. A commercial two-dimensional diode array was used for the measurement. Large discrepancies between the intended and delivered segment MUs were found. The discrepancies were larger for small MU segments at higher dose rate, with some small MU segments completely undelivered. The recorded fractional MUs in the log files were found to agree with what was delivered within the limits of our experimental uncertainty. Our results indicate that it is important to verify the delivery accuracy of small MU segments that could potentially occur in a patient treatment and that the log files are useful in checking the integrity of the linac delivery once validated. Thus validated log files can be used as a QA tool for general IMRT delivery and patient-specific plan verification

Imaging of nasopharyngeal cysts and bursae

International Nuclear Information System (INIS)

Ben Salem, D.; Ricolfi, Frederic; Duvillard, Christian; Ballester, Michel; Assous, Dorothee; Krause, Denis

2006-01-01

Cysts and bursae of the nasopharynx are uncommon and seldom symptomatic when compared with malignant tumors of this region. However, it is noteworthy that in the presence of symptoms, a good knowledge of their radiological appearance is useful to establish the correct diagnosis. Cysts of Rathke's pouch, pharyngeal bursa of Luschka, Tornwaldt's cysts, retentional cysts of the seromucinous glands, oncocytic cysts, intra-adenoid cysts, branchial cysts, prevertebral or retropharyngeal abscess and pseudocysts of the nasopharynx will be discussed in this paper. (orig.)

Histologic and immunohistochemical characteristics of cutaneous cysts in Goltz-Gorlin syndrome: clues for differentiation of nonsyndromic cysts.

Science.gov (United States)

Tirado, Mariantonieta; Ständer, Sonja; Metze, Dieter

2014-11-01

Goltz-Gorlin syndrome presents with multiple basal cell carcinomas, odontogenic keratocysts, and cutaneous cysts, among other manifestations. The cutaneous cysts have been described as both epidermoid cysts and keratocysts but were not further characterized. Light microscopic examinations were made on 23 cutaneous cysts in 4 patients associated with Goltz-Gorlin syndrome located on extremities, face, trunk, palms, and soles and compared with nonsyndromic vellus hair cysts, steatocystomas, and hybrid cysts. Twenty-one of the syndromic cysts revealed alternating infundibular-like and steatocystoma-like squamous epitheliums in varying proportions. The cysts were lined by both smooth and corrugated squamous epithelium. The horny layer was composed by alternating areas of thin, lamellate, and compact eosinophilic keratin. Only 2 cases showed an exclusive steatocystoma-like type of epithelium very similar to odontogenic keratocysts. Sebaceous glands and follicular structures were absent. There were no differences between palmar and plantar cysts and other anatomic locations. The ultrastructural findings in syndromatic cysts confirmed variable expression of keratohyalin granules. Only 3 of 6 cases of nonsyndromic hybrid cysts showed overlapping features with syndromic cysts. Immunohistochemical profiling of keratin, involucrin, filaggrin, loricrin, and BCL-2 expression in syndromatic cysts showed exclusive positivity of K19 and continuous staining for BCL-2. In summary, 2 types of cutaneous cysts are characteristic of Goltz-Gorlin, irrelevant of their anatomic location, namely steatocystoma-like and more frequently hybrid-like. The diagnosis of syndromic hybrid-like cysts should be considered whenever infundibular and steatocystoma differentiation alternate and overlap. Altogether, these findings in epithelial cysts may raise the suspicion of Goltz-Gorlin as an underlying cause.

SU-C-BRB-04: Characteristics and Performance Evaluation of the First Commercial MLC for a Robotic Delivery System

International Nuclear Information System (INIS)

Fuerweger, C; Prins, P; Coskan, H; Heijmen, B

2015-01-01

Purpose: To assess characteristics and performance of the “Incise™” MLC (41 leaf pairs, 2.5mm width, FFF linac) mounted on the robotic SRS/SBRT platform “CyberKnife M6™” in a pre-clinical 5 months (11/2014–03/2015) test period. Methods: Beam properties were measured with unshielded diodes and EBT3 film. The CyberKnife workspace for MLC was analyzed by transforming robot node coordinates (cranial / body paths) into Euler geometry. Bayouth tests for leaf / bank position accuracy were performed in standard (A/P) and clinically relevant non-standard positions, before and after exercising the MLC for 10+ minutes. Total system and delivery accuracy were assessed in End-to-End tests and dosimetric verification of exemplary plans. Stability over time was evaluated in Picket-Fence-and adapted Winston-Lutz-tests (AQA) for different collimator angles. Results: Penumbrae (80–20%, with 100%=2*dose at inflection point; SAD 80cm; 10cm depth) parallel / perpendicular to leaf motion were 2.87/2.64mm for the smallest (0×76×0.75cm 2 ) and 5.34/4.94mm for the largest (9.76×9.75cm 2 ) square field. MLC circular field penumbrae exceeded fixed cones by 10–20% (e.g. 60mm: 4.0 vs. 3.6mm; 20mm: 3.6 vs. 2.9mm). Interleaf leakage was <0.5%. Clinically accessible workspace with MLC covered (non-coplanar) gantry angles of [-113°;+112°] (cranial) and [-108°;+102°] (body), and collimator angles of [-100°;+107°] (cranial) and [-91°;+100°] (body). Average leaf position offsets were ≤0.2mm in 14 standard A/P Bayouth tests and ≤0.6mm in 8 non-standard direction tests. Pre-test MLC exercise increased jaggedness (range ±0.3mm vs. ±0.5mm) and allowed to identify one malfunctioning leaf motor. Total system accuracy with MLC was 0.39±0.06mm in 6 End-to-End tests. Picket-Fence and AQA showed no adverse trends during the test period. Conclusion: The Incise™ MLC for CyberKnife M6™ displayed high accuracy and mechanical stability over the test period. The specific Cyber

SU-C-BRB-04: Characteristics and Performance Evaluation of the First Commercial MLC for a Robotic Delivery System

Energy Technology Data Exchange (ETDEWEB)

Fuerweger, C [Erasmus MC Cancer Institute, Rotterdam (Netherlands); European Cyberknife Center Munich, Munich, DE (Germany); Prins, P; Coskan, H; Heijmen, B [Erasmus MC Cancer Institute, Rotterdam (Netherlands)

2015-06-15

Purpose: To assess characteristics and performance of the “Incise™” MLC (41 leaf pairs, 2.5mm width, FFF linac) mounted on the robotic SRS/SBRT platform “CyberKnife M6™” in a pre-clinical 5 months (11/2014–03/2015) test period. Methods: Beam properties were measured with unshielded diodes and EBT3 film. The CyberKnife workspace for MLC was analyzed by transforming robot node coordinates (cranial / body paths) into Euler geometry. Bayouth tests for leaf / bank position accuracy were performed in standard (A/P) and clinically relevant non-standard positions, before and after exercising the MLC for 10+ minutes. Total system and delivery accuracy were assessed in End-to-End tests and dosimetric verification of exemplary plans. Stability over time was evaluated in Picket-Fence-and adapted Winston-Lutz-tests (AQA) for different collimator angles. Results: Penumbrae (80–20%, with 100%=2*dose at inflection point; SAD 80cm; 10cm depth) parallel / perpendicular to leaf motion were 2.87/2.64mm for the smallest (0×76×0.75cm{sup 2}) and 5.34/4.94mm for the largest (9.76×9.75cm{sup 2}) square field. MLC circular field penumbrae exceeded fixed cones by 10–20% (e.g. 60mm: 4.0 vs. 3.6mm; 20mm: 3.6 vs. 2.9mm). Interleaf leakage was <0.5%. Clinically accessible workspace with MLC covered (non-coplanar) gantry angles of [-113°;+112°] (cranial) and [-108°;+102°] (body), and collimator angles of [-100°;+107°] (cranial) and [-91°;+100°] (body). Average leaf position offsets were ≤0.2mm in 14 standard A/P Bayouth tests and ≤0.6mm in 8 non-standard direction tests. Pre-test MLC exercise increased jaggedness (range ±0.3mm vs. ±0.5mm) and allowed to identify one malfunctioning leaf motor. Total system accuracy with MLC was 0.39±0.06mm in 6 End-to-End tests. Picket-Fence and AQA showed no adverse trends during the test period. Conclusion: The Incise™ MLC for CyberKnife M6™ displayed high accuracy and mechanical stability over the test period. The

Imaging of nasopharyngeal cysts and bursae

Energy Technology Data Exchange (ETDEWEB)

Ben Salem, D.; Ricolfi, Frederic [CHU DIJON, Service de Neuroradiologie et de Radiologie des Urgences, Dijon, Cedex (France); Duvillard, Christian; Ballester, Michel [CHU DIJON, Service d' ORL, Dijon, Cedex (France); Assous, Dorothee [CHU DIJON, Service d' Anatomie et de Cytologie Pathologiques Faculte de Medecine, Dijon, Cedex (France); Krause, Denis [CHU DIJON, Service d' Imagerie Diagnostique et Interventionnelle, Dijon, Cedex (France)

2006-10-15

Cysts and bursae of the nasopharynx are uncommon and seldom symptomatic when compared with malignant tumors of this region. However, it is noteworthy that in the presence of symptoms, a good knowledge of their radiological appearance is useful to establish the correct diagnosis. Cysts of Rathke's pouch, pharyngeal bursa of Luschka, Tornwaldt's cysts, retentional cysts of the seromucinous glands, oncocytic cysts, intra-adenoid cysts, branchial cysts, prevertebral or retropharyngeal abscess and pseudocysts of the nasopharynx will be discussed in this paper. (orig.)

Isolated Cardiac Hydatid Cyst

International Nuclear Information System (INIS)

Shakil, U.; Rehman, A. U.; Shahid, R.

2015-01-01

Hydatid cyst disease is common in our part of the world. Cardiac hydatid cyst is its rare manifestation. We report this case of 48-year male having isolated cardiac hydatid cyst, incidentally found on computed tomography. This patient presented in medical OPD of Combined Military Hospital, Lahore with one month history of mild retrosternal discomfort. His general physical and systemic examinations as well as ECG were unremarkable. Chest X-ray showed an enlarged cardiac shadow with mildly irregular left heart border. Contrast enhanced CT scan of the chest showed a large well defined multiloculated non-enhancing cystic lesion with multiple daughter cysts involving wall of left ventricle and overlying pericardium. Serology for echinococcus confirmed the diagnosis of hydatid cyst. Patient was offered the surgical treatment but he opted for medical treatment only. Albendezol was prescribed. His follow-up echocardiography after one month showed no significant decrease in size of the cyst. (author)

Acetic acid sclerotheraphy of renal cysts

International Nuclear Information System (INIS)

Hong, Hoon Pyo; Oh, Joo Hyeong; Yoon, Yup; Kong, Keun Young; Kim, Eui Jong; Goo, Jang Sung

1998-01-01

Sclerotherapy for renal cysts was performed, using 50% acetic acid as new sclerosing agent. We report the methods and results of this procedure. Fifteen patients underwent sclerotherapy for renal cyst, using 50% acetic acid. Because four patients were lost to follow-up, only 11 of the 15 were included in this study. The renal cysts, including one infected case, were diagnosed by ultrasonograpy (n=3D10) ormagnetic resonance imaging (n=3D1). The patient group consisted of four men and seven women(mean age, 59 years; range, 23-77). At first, the cyst was completely aspirated, and 25 volume% of aspirated volume was replaced with 50% sterile acetic acid through the drainage catheter. During the follwing 20 minutes, the patient changed position, and the acetic acid was then removed from the cyst. Finally, the drainage catheter was removed, after cleaning the cyst with saline. After treatment of infection by antibiotics and catheter drainage for 7 days, sclerotherapy in the infected case followed the same procedure. In order to observe changes in the size of renal cysts and recurrence, all patients were followed up by ultrasound between 2 and 8 months. We defined response to therapy as follows:complete regression as under 5 volume%, partial regression as 5-50 volume% and no response as more than 50 volume% of initial cyst volume. No clinically significant complication occured during the procedures or follow-up periods. All cysts regressed completely during follow-up of 8 months. Complete regression occurred as follows: two cysts at 2 months, seven cysts at 4 months, two cysts at 6 months. Two cysts showed residues at the last follow-up, at 4 and 6 months, respectively. The volume of residual cysts decreased to under 5 volume% of initial volume, however. Completely regressed cysts did not recurr during follow-up. Acetic acid sclerotherapy for renal cysts showed good results, regardless of the dilution of sclerosing agent with residual cyst fluid, and no significant

Development and heritability of subcortical brain volumes at age 9 and 12

NARCIS (Netherlands)

Swagerman, S.C.; Brouwer, R.; de Geus, E.J.C.; Hulshoff Pol, H.E.; Boomsma, D.I.

2014-01-01

Subcortical brain structures are involved in a variety of cognitive and emotional functions and follow different trajectories of increase and decrease in volume from childhood to adulthood. The heritability of development of subcortical brain volumes during adolescence has not been studied

Spinal dermoid cyst

International Nuclear Information System (INIS)

Miyamoto, Yoshihisa; Makita, Yasumasa; Nabeshima, Sachio; Tei, Taikyoku; Keyaki, Atsushi; Takahashi, Jun; Kawamura, Junichiro

1987-01-01

A 25-year-old male complained of intermittent, sharp pains about the left eye and in the left side of the chest. Neurological examination revealed paresthesia and impaired perception of touch and pin-pricks in the dermatomes of Th8 and Th9 on the left side. In all four extremities, the muscle stretch reflexes were equal and slightly hyperactive, without weakness or sensory deficits. Metrizamide myelography showed defective filling at the level between the upper 8th and 9th thoracic vertebrae. The lesion was also demonstrated by computed tomography (CT) scan performed 1 hour later, appearing as an oval, radiolucent mass in the left dorsal spinal canal, which compressed the spinal cord forward and toward the right. Serial sections of the spinal canal revealed the lesion to be partly filled with contrast medium. Repeat CT scan 24 hours after metrizamide myelography showed more contrast medium in the periphery of the lesion, giving it a doughnut-shaped appearance. At surgery a smooth-surfaced cyst containing sebum and white hair was totally removed from the intradural extramedullary space. The histological diagnosis was dermoid cyst. There have been a few reported cases of intracranial epidermoid cyst in which filling of the cyst was suggested on metrizamide CT myelography. These findings may complicate the differential diagnosis of arachnoid cyst and dermoid or epidermoid cyst when only CT is used. (author)

Impact of MLC leaf position errors on simple and complex IMRT plans for head and neck cancer

International Nuclear Information System (INIS)

Mu, G; Ludlum, E; Xia, P

2008-01-01

The dosimetric impact of random and systematic multi-leaf collimator (MLC) leaf position errors is relatively unknown for head and neck intensity-modulated radiotherapy (IMRT) patients. In this report we studied 17 head and neck IMRT patients, including 12 treated with simple plans ( 100 segments). Random errors (-2 to +2 mm) and systematic errors (±0.5 mm and ±1 mm) in MLC leaf positions were introduced into the clinical plans and the resultant dose distributions were analyzed based on defined endpoint doses. The dosimetric effect was insignificant for random MLC leaf position errors up to 2 mm for both simple and complex plans. However, for systematic MLC leaf position errors, we found significant dosimetric differences between the simple and complex IMRT plans. For 1 mm systematic error, the average changes in D 95% were 4% in simple plans versus 8% in complex plans. The average changes in D 0.1cc of the spinal cord and brain stem were 4% in simple plans versus 12% in complex plans. The average changes in parotid glands were 9% in simple plans versus 13% for the complex plans. Overall, simple IMRT plans are less sensitive to leaf position errors than complex IMRT plans

Technical Note: A novel leaf sequencing optimization algorithm which considers previous underdose and overdose events for MLC tracking radiotherapy

Energy Technology Data Exchange (ETDEWEB)

Wisotzky, Eric, E-mail: eric.wisotzky@charite.de, E-mail: eric.wisotzky@ipk.fraunhofer.de; O’Brien, Ricky; Keall, Paul J., E-mail: paul.keall@sydney.edu.au [Radiation Physics Laboratory, Sydney Medical School, University of Sydney, Sydney, NSW 2006 (Australia)

2016-01-15

Purpose: Multileaf collimator (MLC) tracking radiotherapy is complex as the beam pattern needs to be modified due to the planned intensity modulation as well as the real-time target motion. The target motion cannot be planned; therefore, the modified beam pattern differs from the original plan and the MLC sequence needs to be recomputed online. Current MLC tracking algorithms use a greedy heuristic in that they optimize for a given time, but ignore past errors. To overcome this problem, the authors have developed and improved an algorithm that minimizes large underdose and overdose regions. Additionally, previous underdose and overdose events are taken into account to avoid regions with high quantity of dose events. Methods: The authors improved the existing MLC motion control algorithm by introducing a cumulative underdose/overdose map. This map represents the actual projection of the planned tumor shape and logs occurring dose events at each specific regions. These events have an impact on the dose cost calculation and reduce recurrence of dose events at each region. The authors studied the improvement of the new temporal optimization algorithm in terms of the L1-norm minimization of the sum of overdose and underdose compared to not accounting for previous dose events. For evaluation, the authors simulated the delivery of 5 conformal and 14 intensity-modulated radiotherapy (IMRT)-plans with 7 3D patient measured tumor motion traces. Results: Simulations with conformal shapes showed an improvement of L1-norm up to 8.5% after 100 MLC modification steps. Experiments showed comparable improvements with the same type of treatment plans. Conclusions: A novel leaf sequencing optimization algorithm which considers previous dose events for MLC tracking radiotherapy has been developed and investigated. Reductions in underdose/overdose are observed for conformal and IMRT delivery.

Epidermoid cyst in the kidney.

Science.gov (United States)

Desai, Saral; Thakur, Sudeep; Menon, Santosh; Desai, Sangeeta B

2011-09-01

We report an extremely rare case of an epidermoid cyst in the kidney of a 74-year-old man who had presented with painless hematuria. Radiologic examination revealed a cyst in the kidney that was thought to be neoplastic. The patient underwent surgery to remove the cyst, and we received the nephrectomy specimen. A 6-cm cyst with no solid areas was seen. On histologic examination, this was an epidermoid cyst. We reviewed the published data and discuss the possible theories of origin of this rare condition. Copyright © 2011 Elsevier Inc. All rights reserved.

Multiple cerebral hydatid cysts

Energy Technology Data Exchange (ETDEWEB)

Banzo, J.; Pina, J.I.; Abos, M.D.; Rios, G.; Garcia, D.; Marin, F.; Diaz, F.J.

1984-12-01

A 39-year-old woman was admitted to hospital with headaches, vomiting, psychic impairment and diplopia. Three hydatid cysts of the lung had been previously removed. An avascular mass in the left hemisphere with left-to-right displacement of the anterior cerebral arteries was noted during a brain angioscintigraphy. A cerebralthrombosis (CT) brain scan showed two cystic lesions situated in the left-frontal and occipital regions. A CT abdominal scan showed multiple cysts in the liver, spleen and both kidneys. At operation, two brain cysts were totally extirpated without rupture. The definite pathological diagnosis was secondry hydatid cysts. The headaches, vomiting and diplopia were persistent in the post-operative period. Seven days after the operation, a CT brain scan showed an infratenrorial cyst. The patient rejected any surgical intervention.

Pancreas and cyst segmentation

Science.gov (United States)

Dmitriev, Konstantin; Gutenko, Ievgeniia; Nadeem, Saad; Kaufman, Arie

2016-03-01

Accurate segmentation of abdominal organs from medical images is an essential part of surgical planning and computer-aided disease diagnosis. Many existing algorithms are specialized for the segmentation of healthy organs. Cystic pancreas segmentation is especially challenging due to its low contrast boundaries, variability in shape, location and the stage of the pancreatic cancer. We present a semi-automatic segmentation algorithm for pancreata with cysts. In contrast to existing automatic segmentation approaches for healthy pancreas segmentation which are amenable to atlas/statistical shape approaches, a pancreas with cysts can have even higher variability with respect to the shape of the pancreas due to the size and shape of the cyst(s). Hence, fine results are better attained with semi-automatic steerable approaches. We use a novel combination of random walker and region growing approaches to delineate the boundaries of the pancreas and cysts with respective best Dice coefficients of 85.1% and 86.7%, and respective best volumetric overlap errors of 26.0% and 23.5%. Results show that the proposed algorithm for pancreas and pancreatic cyst segmentation is accurate and stable.

Monte Carlo modeling and simulations of the High Definition (HD120) micro MLC and validation against measurements for a 6 MV beam

International Nuclear Information System (INIS)

Borges, C.; Zarza-Moreno, M.; Heath, E.; Teixeira, N.; Vaz, P.

2012-01-01

Purpose: The most recent Varian micro multileaf collimator (MLC), the High Definition (HD120) MLC, was modeled using the BEAMNRC Monte Carlo code. This model was incorporated into a Varian medical linear accelerator, for a 6 MV beam, in static and dynamic mode. The model was validated by comparing simulated profiles with measurements. Methods: The Varian Trilogy (2300C/D) accelerator model was accurately implemented using the state-of-the-art Monte Carlo simulation program BEAMNRC and validated against off-axis and depth dose profiles measured using ionization chambers, by adjusting the energy and the full width at half maximum (FWHM) of the initial electron beam. The HD120 MLC was modeled by developing a new BEAMNRC component module (CM), designated HDMLC, adapting the available DYNVMLC CM and incorporating the specific characteristics of this new micro MLC. The leaf dimensions were provided by the manufacturer. The geometry was visualized by tracing particles through the CM and recording their position when a leaf boundary is crossed. The leaf material density and abutting air gap between leaves were adjusted in order to obtain a good agreement between the simulated leakage profiles and EBT2 film measurements performed in a solid water phantom. To validate the HDMLC implementation, additional MLC static patterns were also simulated and compared to additional measurements. Furthermore, the ability to simulate dynamic MLC fields was implemented in the HDMLC CM. The simulation results of these fields were compared with EBT2 film measurements performed in a solid water phantom. Results: Overall, the discrepancies, with and without MLC, between the opened field simulations and the measurements using ionization chambers in a water phantom, for the off-axis profiles are below 2% and in depth-dose profiles are below 2% after the maximum dose depth and below 4% in the build-up region. On the conditions of these simulations, this tungsten-based MLC has a density of 18.7 g

Cyclin d1 expression in odontogenic cysts.

Science.gov (United States)

Taghavi, Nasim; Modabbernia, Shirin; Akbarzadeh, Alireza; Sajjadi, Samad

2013-01-01

In the present study expression of cyclin D1 in the epithelial lining of odontogenic keratocyst, radicular cyst, dentigerous cyst and glandular odontogenic cyst was investigated to compare proliferative activity in these lesions. Immunohistochemical staining of cyclin D1 on formalin-fixed, paraffin-embedded tissue sections of odontogenic keratocysts (n=23), dentigerous cysts (n=20), radicular cysts (n=20) and glandular odontogenic cysts (n=5) was performed by standard EnVision method. Then, slides were studied to evaluate the following parameters in epithelial lining of cysts: expression, expression pattern, staining intensity and localization of expression. The data analysis showed statistically significant difference in cyclin D1 expression in studied groups (p keratocysts, but difference was not statistically significant among groups respectively (p=0.204, 0.469). Considering expression localization, cyclin D1 positive cells in odontogenic keratocysts and dentigerous cysts were frequently confined in parabasal layer, different from radicular cysts and glandular odontogenic cysts. The difference was statistically significant (p keratocyst and the entire cystic epithelium of glandular odontogenic cysts comparing to dentigerous cysts and radicular cysts, implying the possible role of G1-S cell cycle phase disturbances in the aggressiveness of odontogenic keratocyst and glandular odontogenic cyst.

Globulomaxillary cysts--do they really exist?

Science.gov (United States)

Dammer, U; Driemel, O; Mohren, W; Giedl, C; Reichert, T E

2014-01-01

The so-called "globulomaxillary cyst", described as a fissural cyst, caused by entrapped epithelium between the nasal and maxillary process, is no longer considered for its own entity. Nevertheless, cystic lesions, which correspond to the previous image of globulomaxillary cysts, do still occur in daily practice. This raises the question to which entities pathological processes in this particular region actually belong to. In a retrospective study, 17 cases (12 men and 5 women, 12-59 years old) of primarily diagnosed globulomaxillary cysts are analysed according to clinical, radiological and histological aspects, catamnestic processed and assigned to a new entity. The results are compared with the international literature and draws conclusions on the diagnostic and therapeutic procedure. Seven lateral periodontal cysts, four radicular cysts, two keratocystic odontogenic tumours, one adenomatoid odontogenic tumour, one periapical granuloma, one residual cyst and one undefined jaw cyst were determined. According to the results of our study and the data from the international literature, the entity globulomaxillary cyst is no longer justified.

Drastic increase of myosin light chain MLC-2 in senescent skeletal muscle indicates fast-to-slow fibre transition in sarcopenia of old age.

Science.gov (United States)

Gannon, Joan; Doran, Philip; Kirwan, Anne; Ohlendieck, Kay

2009-11-01

The age-dependent decline in skeletal muscle mass and function is believed to be due to a multi-factorial pathology and represents a major factor that blocks healthy aging by increasing physical disability, frailty and loss of independence in the elderly. This study has focused on the comparative proteomic analysis of contractile elements and revealed that the most striking age-related changes seem to occur in the protein family representing myosin light chains (MLCs). Comparative screening of total muscle extracts suggests a fast-to-slow transition in the aged MLC population. The mass spectrometric analysis of the myofibril-enriched fraction identified the MLC2 isoform of the slow-type MLC as the contractile protein with the most drastically changed expression during aging. Immunoblotting confirmed an increased abundance of slow MLC2, concomitant with a switch in fast versus slow myosin heavy chains. Staining of two-dimensional gels of crude extracts with the phospho-specific fluorescent dye ProQ-Diamond identified the increased MLC2 spot as a muscle protein with a drastically enhanced phosphorylation level in aged fibres. Comparative immunofluorescence microscopy, using antibodies to fast and slow myosin isoforms, confirmed a fast-to-slow transformation process during muscle aging. Interestingly, the dramatic increase in slow MLC2 expression was restricted to individual senescent fibres. These findings agree with the idea that aged skeletal muscles undergo a shift to more aerobic-oxidative metabolism in a slower-twitching fibre population and suggest the slow MLC2 isoform as a potential biomarker for fibre type shifting in sarcopenia of old age.

Cellular complexity in subcortical white matter: a distributed control circuit?

Science.gov (United States)

Colombo, Jorge A

2018-03-01

The subcortical white matter (SWM) has been traditionally considered as a site for passive-neutral-information transfer through cerebral cortex association and projection fibers. Yet, the presence of subcortical neuronal and glial "interstitial" cells expressing immunolabelled neurotransmitters/neuromodulators and synaptic vesicular proteins, and recent immunohistochemical and electrophysiological observations on the rat visual cortex as well as interactive regulation of myelinating processes support the possibility that SWM nests subcortical, regionally variable, distributed neuronal-glial circuits, that could influence information transfer. Their hypothetical involvement in regulating the timing and signal transfer probability at the SWM axonal components ought to be considered and experimentally analysed. Thus, the "interstitial" neuronal cells-associated with local glial cells-traditionally considered to be vestigial and functionally inert under normal conditions, they may well turn to be critical in regulating information transfer at the SWM.

Gray matter volume changes in chronic subcortical stroke: A cross-sectional study

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Qingqing Diao

2017-01-01

Full Text Available This study aimed to investigate the effects of lesion side and degree of motor recovery on gray matter volume (GMV difference relative to healthy controls in right-handed subcortical stroke. Structural MRI data were collected in 97 patients with chronic subcortical ischemic stroke and 79 healthy controls. Voxel-wise GMV analysis was used to investigate the effects of lesion side and degree of motor recovery on GMV difference in right-handed chronic subcortical stroke patients. Compared with healthy controls, right-lesion patients demonstrated GMV increase (P < 0.05, voxel-wise false discovery rate correction in the bilateral paracentral lobule (PCL and supplementary motor area (SMA and the right middle occipital gyrus (MOG; while left-lesion patients did not exhibit GMV difference under the same threshold. Patients with complete and partial motor recovery showed similar degree of GMV increase in right-lesion patients. However, the motor recovery was correlated with the GMV increase in the bilateral SMA in right-lesion patients. These findings suggest that there exists a lesion-side effect on GMV difference relative to healthy controls in right-handed patients with chronic subcortical stroke. The GMV increase in the SMA may facilitate motor recovery in subcortical stroke patients.

Effect of MLC Leaf Width and PTV Margin on the Treatment Planning of Intensity-Modulated Stereotactic Radiosurgery (IMSRS) or Radiotherapy (IMSRT)

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Chang Jenghwa; Yenice, Kamil M.; Jiang Kailiu; Hunt, Margie; Narayana, Ashwatha

2009-01-01

We studied the effect of MLC (multileaf collimator) leaf width and PTV (planning target volume) margin on treatment planning of intensity modulated stereotactic radiosurgery (IMSRS) or radiotherapy (IMSRT). Twelve patients previously treated with IMSRS/IMSRT were retrospectively planned with 5- and 3-mm MLC leaf widths and 3- and 2-mm PTV margins using the already contoured clinical target volume and critical structures. The same beam arrangement, planning parameters, and optimization method were used in each of the 4 plans for a given patient. Each plan was normalized so that the prescription dose covered at least 99% of the PTV. Plan indices - D mean (mean dose), conformity index (CI), V 70 (volume receiving ≥ 70% of the prescription dose), and V 50 (volume receiving ≥ 50% of the prescription dose) - were calculated from the dose-volume histograms (DVHs) of the PTV, normal tissue, and organs at risk (OARs). Hypothesis testing was performed on the mean ratios of plan indices to determine the statistical significance of the relative differences. The PTV was well covered for all plans, as no significant differences were observed for D 95 , V 95 , D max , D min , and D mean of the PTV. The irradiated volume was ∼23% smaller when 2-mm instead of 3-mm PTV margin was used, but it was only reduced by ∼6% when the MLC leaf width was reduced from 5 mm to 3 mm. For normal tissue and brainstem, V 70 , V 50 , and D mean were reduced more effectively by a decrease in MLC width, while D mean of optic nerve and chiasm were more sensitive to a change in PTV margin. The DVH statistics for the PTV and normal structures from the treatment plan with 5-mm MLC and 2-mm PTV margin were equal to those with 3-mm MLC and 3-mm PTV margin. PTV margin reduction is more effective in sparing the normal tissue and OARs than a reduction in MLC leaf width. For IMSRS, where highly accurate setup and small PTV margins are routinely employed, the use of 5-mm MLC is therefore less desirable.

Ovarian chocolate cysts

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Sugimura, Kazuro; Ishida, Tetsuya; Takemori, Masayuki; Kitagaki, Hajime; Tanaka, Yutaka; Yamasaki, Katsuhito; Shimizu, Tadafumi; Kono, Michio.

1988-01-01

Accurate preoperative staging of ovarian chocolate cysts is very important because recent hormonal therapy has been effective in low stage patients. However, it has been difficult to assess the preoperative stage of ovarian chocolate cysts. We evaluated the diagnostic potential of MRI in preoperative staging of 15 overian chocolate cysts. It was well known that the older the ovarian chocolate cyst was the more iron content it had. We examined the iron contents effect on T1 and T2 relaxation times in surgically confirmed chocolate cysts (stage II: 3 cases, stage III: 3 cases and stage IV: 9 cases by AFS classification, 1985) employing the 0.15-T MR system and 200 MHz spectrometer. There was a positive linear relation between T1 of the lesion using the MR system (T1) and T1 of the resected contents using the spectrometer (sp-T1); r = 0.93. The same relation was revealed between T2 and sp-T2; r = 0.87. It was indicated that T1 and T2 using the MR system was accurate. There was a negative linear relation between T1 and the iron contents ( r = -0.81) but no relation between T2 and the iron contents. T1 was 412 ± 91 msec for stage II, 356 ± 126 msec for stage III and 208 ± 30 msec for stage IV. T1 for stage IV was shorter than that for stage II and III, statistically significant differences were noted (p < 0.05). Thus, T1 was useful in differentiating a fresh from an old ovarian chocolate cyst. We concluded that T1 relaxation time using the MR system was useful for the staging of an ovarian chocolate cyst without surgery. (author)

Development of the yellow potato cyst nematode Globodera rostochiensis (Woll.) on potatoes after gamma irradiation of cysts

International Nuclear Information System (INIS)

Karnkowski, W.; Ignatowicz, S.

1999-01-01

Gamma irradiation inhibited the development of the yellow potato cyst nematode, Globodera rostochiensis (Woll.) Behrens when cysts containing juveniles in anabiosis were irradiated with a dose of 0.5 kGy or higher. A dose of 0.5 kGy reduced the infestation level and the density of females/cysts on root of infested plants. However, a few cysts were found on roots of plants grown in pots with soil treated with a dose of 3.0 kGy. Development of the second generation of the potato cyst nematode (= F1 cysts that originated from irradiated cysts) was much weaker than that of the parental generation. The F1 females and/or cysts were found only in the control and in the 0.5 kGy treatment in low numbers. (author)

Validation of Varian TrueBeam electron phase–spaces for Monte Carlo simulation of MLC-shaped fields

International Nuclear Information System (INIS)

Lloyd, Samantha A. M.; Gagne, Isabelle M.; Zavgorodni, Sergei; Bazalova-Carter, Magdalena

2016-01-01

Purpose: This work evaluates Varian’s electron phase–space sources for Monte Carlo simulation of the TrueBeam for modulated electron radiation therapy (MERT) and combined, modulated photon and electron radiation therapy (MPERT) where fields are shaped by the photon multileaf collimator (MLC) and delivered at 70 cm SSD. Methods: Monte Carlo simulations performed with EGSnrc-based BEAMnrc/DOSXYZnrc and PENELOPE-based PRIMO are compared against diode measurements for 5 × 5, 10 × 10, and 20 × 20 cm 2 MLC-shaped fields delivered with 6, 12, and 20 MeV electrons at 70 cm SSD (jaws set to 40 × 40 cm 2 ). Depth dose curves and profiles are examined. In addition, EGSnrc-based simulations of relative output as a function of MLC-field size and jaw-position are compared against ion chamber measurements for MLC-shaped fields between 3 × 3 and 25 × 25 cm 2 and jaw positions that range from the MLC-field size to 40 × 40 cm 2 . Results: Percent depth dose curves generated by BEAMnrc/DOSXYZnrc and PRIMO agree with measurement within 2%, 2 mm except for PRIMO’s 12 MeV, 20 × 20 cm 2 field where 90% of dose points agree within 2%, 2 mm. Without the distance to agreement, differences between measurement and simulation are as large as 7.3%. Characterization of simulated dose parameters such as FWHM, penumbra width and depths of 90%, 80%, 50%, and 20% dose agree within 2 mm of measurement for all fields except for the FWHM of the 6 MeV, 20 × 20 cm 2 field which falls within 2 mm distance to agreement. Differences between simulation and measurement exist in the profile shoulders and penumbra tails, in particular for 10 × 10 and 20 × 20 cm 2 fields of 20 MeV electrons, where both sets of simulated data fall short of measurement by as much as 3.5%. BEAMnrc/DOSXYZnrc simulated outputs agree with measurement within 2.3% except for 6 MeV MLC-shaped fields. Discrepancies here are as great as 5.5%. Conclusions: TrueBeam electron phase–spaces available from Varian have been

Branchial cleft cyst

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Vaishali Nahata

2016-01-01

Full Text Available Branchial cleft cyst, sinuses, and fistulae are among the most commonly encountered congenital anomalies in pediatric otolaryngic practice. They can present difficulty in diagnosis and surgical management. Here, I report a case of 14-year-old boy who presented with asymptomatic, congenital swelling located just below the jawline in the lateral part of the neck. The lesion was excised surgically. Histopathology showed the cyst lined by squamous as well as columnar ciliated epithelium, which was a characteristic finding of branchial cleft cyst. The aim of presenting this case is its rarity.

Branchial Cleft Cyst

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Nahata, Vaishali

2016-01-01

Branchial cleft cyst, sinuses, and fistulae are among the most commonly encountered congenital anomalies in pediatric otolaryngic practice. They can present difficulty in diagnosis and surgical management. Here, I report a case of 14-year-old boy who presented with asymptomatic, congenital swelling located just below the jawline in the lateral part of the neck. The lesion was excised surgically. Histopathology showed the cyst lined by squamous as well as columnar ciliated epithelium, which was a characteristic finding of branchial cleft cyst. The aim of presenting this case is its rarity. PMID:27904209

Branchial Cleft Cyst.

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Nahata, Vaishali

2016-01-01

Branchial cleft cyst, sinuses, and fistulae are among the most commonly encountered congenital anomalies in pediatric otolaryngic practice. They can present difficulty in diagnosis and surgical management. Here, I report a case of 14-year-old boy who presented with asymptomatic, congenital swelling located just below the jawline in the lateral part of the neck. The lesion was excised surgically. Histopathology showed the cyst lined by squamous as well as columnar ciliated epithelium, which was a characteristic finding of branchial cleft cyst. The aim of presenting this case is its rarity.

Nasopalatine duct cyst: A case report

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Saikrishna Pasupuleti

2015-01-01

Full Text Available Nasopalatine duct cyst (NPDC is the most common non-odontogenic cyst of oral cavity. Clinically, Nasopalatine duct cyst manifests as an asymptomatic swelling of the palate or the upper lip. Radiographically, it is seen as a heart-shaped radiolucency and can be confused with periapical pathology. The aim of this article is to report a case of a nasopalatine duct cyst in a 36-year-old patient which was misinterpreted for a periapical cyst. Diagnosis of a Nasopalatine duct cyst can be given through clinical, radiographical, and histopathological examination.

Effectiveness and Safety of MLC601 in the Treatment of Mild to Moderate Alzheimer's Disease: A Multicenter, Randomized Controlled Trial

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Hossein Pakdaman

2015-03-01

Full Text Available Background: MLC601 is a possible modulator of amyloid precursor protein processing, and in a clinical trial study MLC601 showed some effectiveness in cognitive function in Alzheimer's disease (AD patients. We aimed to evaluate the effectiveness and safety of MLC601 in the treatment of mild to moderate AD as compared to 3 approved cholinesterase inhibitors (ChEIs including donepezil, rivastigmine and galantamine. Methods: In a multicenter, nonblinded, randomized controlled trial, 264 volunteers with AD were randomly divided into 4 groups of 66; groups 1, 2, 3 and 4 received donepezil, rivastigmine, MLC601 and galantamine, respectively. Subjects underwent a clinical diagnostic interview and a cognitive/functional battery including the Mini-Mental State Examination (MMSE and Alzheimer's Disease Assessment Scale - Cognitive subscale (ADAS-Cog. Patients were visited every 4 months, and the score of cognition was recorded by the neurologists. Results: There were no significant differences in age, sex, marital status and baseline score of cognition among the 4 groups. In total, 39 patients (14.7% left the study. Trend of cognition changes based on the modifications over the time for MMSE and ADAS-cog scores did not differ significantly among groups (p = 0.92 for MMSE and p = 0.87 for ADAS-Cog. Conclusion: MLC601 showed a promising safety profile and also efficacy compared to 3 FDA-approved ChEIs.

[Arachnoid cysts: Embriology and pathology].

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García-Conde, Mario; Martín-Viota, Lucia

2015-01-01

There is still great controversy surrounding the origin of the arachnoid cyst. The most accepted theory in the case of congenital cysts explains how they are formed from an anomalous development of the arachnoid membrane, which is unfolded allowing the accumulation of cerebrospinal fluid inside and creating a cyst. This theory seems to explain the origin of convexity and sylvian cistern arachnoid cysts, whereas those in other locations might be due to other mechanisms. In the anatomopathological analysis, the arachnoid cyst wall can be seen as having few differences from normal, although thickened due to an increase quantity of collagenous material. A description of the embryological development of the arachnoid layer and cyst formation is presented, describing the main anatomopathological findings. Copyright © 2015 Sociedad Española de Neurocirugía. Published by Elsevier España. All rights reserved.

A lymphoepithelial cyst (branchial cyst) in the floor of the mouth.

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Kumara, G R; Gillgrass, T J; Bridgman, J B

1995-03-01

Lymphoepithelial cysts are developmental, but their pathogenesis is unknown. The classical explanation is that they are derived from remnants of the branchial arches or clefts. This has been disputed, and it is likely that most arise from epithelium, possibly of tonsillar or salivary origin, that becomes entrapped by lymphoid tissue. This report describes a lymphoepithelial cyst in a 29-year-old man. The cyst was situated on the right side of the floor of the mouth adjacent to the lingual frenum. Its appearance supports both branchiogenic and the entrapment theories.

Reduced prefrontal and increased subcortical brain functioning assessed using positron emission tomography in predatory and affective murderers.

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Raine, A; Meloy, J R; Bihrle, S; Stoddard, J; LaCasse, L; Buchsbaum, M S

1998-01-01

There appear to be no brain imaging studies investigating which brain mechanisms subserve affective, impulsive violence versus planned, predatory violence. It was hypothesized that affectively violent offenders would have lower prefrontal activity, higher subcortical activity, and reduced prefrontal/subcortical ratios relative to controls, while predatory violent offenders would show relatively normal brain functioning. Glucose metabolism was assessed using positron emission tomography in 41 comparisons, 15 predatory murderers, and nine affective murderers in left and right hemisphere prefrontal (medial and lateral) and subcortical (amygdala, midbrain, hippocampus, and thalamus) regions. Affective murderers relative to comparisons had lower left and right prefrontal functioning, higher right hemisphere subcortical functioning, and lower right hemisphere prefrontal/subcortical ratios. In contrast, predatory murderers had prefrontal functioning that was more equivalent to comparisons, while also having excessively high right subcortical activity. Results support the hypothesis that emotional, unplanned impulsive murderers are less able to regulate and control aggressive impulses generated from subcortical structures due to deficient prefrontal regulation. It is hypothesized that excessive subcortical activity predisposes to aggressive behaviour, but that while predatory murderers have sufficiently good prefrontal functioning to regulate these aggressive impulses, the affective murderers lack such prefrontal control over emotion regulation.

SU-E-T-312: Dosimetric Consideration for the Agility MLC When Planning Rotational SRT/SBRT Treatments

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Kong, X; Harris, J; Spitznagel, D; Walker, J [Avera Medical Group - Radiation Oncology, Sioux Falls, SD (United States)

2015-06-15

Purpose: To analyze the radiation transmission of the Agility MLC and make recommendation based on the MLC dosimetric characteristics for SRT, SBRT and VMAT planning Method and Materials: Agility MLC is the newest model from Elekta and has no back up diaphragm behind leaves for this generation. Leaves are single focused with rounded end; composed of leafs each 0.5cm wide, 9cm thick, constructed from tungsten alloy and provide low transmission <0.5%. Total radiation transmission from leaves and diaphragm is <0.13%. A 360degree arc was generated using iCom tools; leaves were programmed closed while keeping the diaphragm fully open to maximize the MLC transmission effect. Gafchromic EBT films were sandwiched between 4cm of solid water and situated at midplane to take dose measurement. 5000MU was delivered using 6MV VersaHD, various collimator angles, and a 5cm central axis offset was tested also. Films were scanned with Epson 10000XL scanner and analyzed using DoseLab Pro. Results: Due to the rounded leaf end and nature of rotation therapy, dose accumulation through the leaf gap is significant. By offsetting the leaf gap from central axis, this accumulation can be greatly reduced. There are dark bands showing accumulation of interleaf transmission which is improved by increasing collimator angle from 0 to 45dgree. However for 45 degree, in most cases, there are larger volumes sweeping under MLC alone, which needs considered planning. Conclusions: While inter-leaf leakage is minimized by using collimator angles greater than 0 degrees, the location of the leaf gap must also be managed. The leaf gap position becomes critically important when the treatment area is off axis such is the case when more than one PTV is being treated. With VMAT for SRT, SBRT becoming a more popular planning technique, special attention needs to be paid when initially setting up the field geometry.

Examining the subcortical infarcts in the era of acute multimodality CT imaging

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Mindy Tan

2016-12-01

Full Text Available Background: Lacunar infarcts have been characterized as small subcortical infarcts, resulting from in situ microatheroma or lipohyalinosis in small vessels. Based on this hypothesis, such infarcts should not be associated with large areas of perfusion deficits extending beyond subcortical regions to involve cortical regions. By contrast, selected small subcortical infarcts, as defined by MR imaging in the subacute or chronic stage, may initially have large perfusion deficits or related large vessel occlusions. These infarcts with ‘lacunar’ phenotype may also be caused by disease in the parent vessel and may have very different stroke mechanisms from small vessel disease. Our aim was to describe differences in imaging characteristics between patients with small subcortical infarction with ‘lacunar phenotype’ from those with lacunar mechanism. Methods: Patients undergoing acute CT Perfusion/angiography (CTP/CTA within 6 hours of symptom onset and follow-up magnetic resonance imaging (MRI for ischaemic stroke were included (2009-2013. A lacunar infarct was defined as a single subcortical infarct (SSI ≤20 mm on follow-up MRI. Presence of perfusion deficits, vessel occlusion and infarct dimensions were compared between lacunar infarcts and other topographical infarct types. Results: Overall, 182 patients (mean age 66.4±15.3 years, 66% male were included. SSI occurred in 31 (17% patients. Of these, 12 (39% patients had a perfusion deficit compared with those with any cortical infarction (120/142, 67%, and the smallest SSI with a perfusion deficit had a diameter of <5mm. The majority of patients with SSI (8/12, 66.7% had a relevant vessel occlusion. A quarter of SSIs had a large-artery stroke mechanism evident on acute CTP/CTA. Lacunar mechanism was present in 3/8 patients with corona radiata, 5/10 lentiform nucleus, 5/6 posterior limb of internal capsule PLIC, 3/5 thalamic infarcts and 1/2 miscellaneous locations. There was a trend toward

CT findings and clinical analysis of subcortical hematomas in elderly patients

International Nuclear Information System (INIS)

Ueno, Yasushi; Tanaka, Akira; Yoshinaga, Shinya; Kimura, Masato

1991-01-01

Ten elderly patients (73-87 years, 78.4 years on the average) with subcortical hematomas were divided into two groups according to the shape of the hematoma on a CT scan: a lobulated group (6 patients) and a global group (4 patients). The lobulated group had a history of hypertension in one patient. The hematomas extended widely around the parietal lobe and were accompanied by perifocal edema, brain shifts and subarachnoid hemorrhages, deep consciousness disturbances, and poor prognosis of life and function. Amyloid depositions in the arteries around the hematomas were confirmed histologically in one patient. The global group had a history of hypertension in two patients. The hematomas were localized in the parietal, temporal, or occipital lobe without perifocal edema, brain shift and subarachnoid hemorrhages, and accompanied by mild consciousness disturbances. The life prognosis was good, but the functional prognosis was poor, with a subsequent development of dementia. A lobulated subcortical hematoma is thought to be due to amyloid angiopathy, while a global subcortical hematoma is thought to be due to hypertension. A surgical evacuation is seldom indicated for either type of subcortical hematoma in elderly patients. (author)

Subcortical White Matter Changes with Normal Aging Detected by Multi-Shot High Resolution Diffusion Tensor Imaging.

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Sheng Xie

Full Text Available Subcortical white matter builds neural connections between cortical and subcortical regions and constitutes the basis of neural networks. It plays a very important role in normal brain function. Various studies have shown that white matter deteriorates with aging. However, due to the limited spatial resolution provided by traditional diffusion imaging techniques, microstructural information from subcortical white matter with normal aging has not been comprehensively assessed. This study aims to investigate the deterioration effect with aging in the subcortical white matter and provide a baseline standard for pathological disorder diagnosis. We apply our newly developed multi-shot high resolution diffusion tensor imaging, using self-feeding multiplexed sensitivity-encoding, to measure subcortical white matter changes in regions of interest of healthy persons with a wide age range. Results show significant fractional anisotropy decline and radial diffusivity increasing with age, especially in the anterior part of the brain. We also find that subcortical white matter has more prominent changes than white matter close to the central brain. The observed changes in the subcortical white matter may be indicative of a mild demyelination and a loss of myelinated axons, which may contribute to normal age-related functional decline.

The spectrum of leukodystrophies in children: Experience at a tertiary care centre from North India

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Sheffali Gulati

2016-01-01

Full Text Available Objective: The objective of this study is to retrospectively collect and then describe the clinico-radiographical profile of confirmed cases of leukodystrophy who presented over a 5-year period to a tertiary care teaching hospital in North India. Materials and Methods: The case records of 80 confirmed cases of leukodystrophy were reviewed and the cases have been described in terms of their clinical presentation and neuroimaging findings. Results: The cases have been grouped into five categories: Hypomyelinating, demyelinating, disorders with vacuolization, cystic, and miscellaneous. The commonest leukodystrophies are megalencephalic leukoencephalopathy with subcortical cysts (MLC, Pelizaeus-Merzbacher disease (PMD, and metachromatic leukodystrophy (MLD. A notable proportion of hypomyelinating disorders were uncharacterized. Conclusions: Leukodystrophies at this point of time have no definite cure. They have a progressively downhill clinical course. Early diagnosis is imperative for appropriate genetic counseling. A simplified approach to diagnose common leukodystrophies has also been provided. It is important to develop a registry, which can provide valuable epidemiological data to prioritize research in this field, which has many unanswered questions.

Ovarian cysts on prenatal MRI

International Nuclear Information System (INIS)

Nemec, Ursula; Nemec, Stefan F.; Bettelheim, Dieter; Brugger, Peter C.; Horcher, Ernst; Schöpf, Veronika; Graham, John M.; Rimoin, David L.; Weber, Michael; Prayer, Daniela

2012-01-01

Objective: Ovarian cysts are the most frequently encountered intra-abdominal masses in females in utero. They may, at times, require perinatal intervention. Using magnetic resonance imaging (MRI) as an adjunct to ultrasonography (US) in prenatal diagnosis, we sought to demonstrate the ability to visualize ovarian cysts on prenatal MRI. Materials and methods: This retrospective study included 17 fetal MRI scans from 16 female fetuses (23–37 gestational weeks) with an MRI diagnosis of ovarian cysts after suspicious US findings. A multiplanar MRI protocol was applied to image and to characterize the cysts. The US and MRI findings were compared, and the prenatal findings were compared with postnatal imaging findings or histopathology. Results: Simple ovarian cysts were found in 10/16 cases and complex cysts in 7/16 cases, including one case with both. In 11/16 (69%) cases, US and MRI diagnoses were in agreement, and, in 5/16 (31%) cases, MRI specified or expanded the US diagnosis. In 6/16 cases, postnatal US showed that the cysts spontaneously resolved or decreased in size, and in 1/16 cases, postnatal imaging confirmed a hemorrhagic cyst. In 4/16 cases, the prenatal diagnoses were confirmed by surgery/histopathology, and for the rest, postnatal correlation was not available. Conclusion: Our results illustrate the MRI visualization of ovarian cysts in utero. In most cases, MRI will confirm the US diagnosis. In certain cases, MRI may provide further diagnostic information, additional to US, which is the standard technique for diagnosis, monitoring, and treatment planning.

Ovarian cysts on prenatal MRI

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Nemec, Ursula [Department of Radiology, Division of Neuroradiology and Musculoskeletal Radiology, Medical University Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Nemec, Stefan F., E-mail: stefan.nemec@meduniwien.ac.at [Department of Radiology, Division of Neuroradiology and Musculoskeletal Radiology, Medical University Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Medical Genetics Institute, Cedars Sinai Medical Center, 8700 Beverly Boulevard, PACT Suite 400, Los Angeles, CA 90048 (United States); Bettelheim, Dieter [Department of Obstetrics and Gynaecology, Division of Prenatal Diagnosis and Therapy, Medical University Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Brugger, Peter C. [Center of Anatomy and Cell Biology, Integrative Morphology Group, Medical University Vienna, Waehringerstrasse 13, A-1090 Vienna (Austria); Horcher, Ernst [Department of Pediatric Surgery, Medical University Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Schoepf, Veronika [Department of Radiology, Division of Neuroradiology and Musculoskeletal Radiology, Medical University Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Graham, John M.; Rimoin, David L. [Medical Genetics Institute, Cedars Sinai Medical Center, 8700 Beverly Boulevard, PACT Suite 400, Los Angeles, CA 90048 (United States); Weber, Michael; Prayer, Daniela [Department of Radiology, Division of Neuroradiology and Musculoskeletal Radiology, Medical University Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria)

2012-08-15

Objective: Ovarian cysts are the most frequently encountered intra-abdominal masses in females in utero. They may, at times, require perinatal intervention. Using magnetic resonance imaging (MRI) as an adjunct to ultrasonography (US) in prenatal diagnosis, we sought to demonstrate the ability to visualize ovarian cysts on prenatal MRI. Materials and methods: This retrospective study included 17 fetal MRI scans from 16 female fetuses (23-37 gestational weeks) with an MRI diagnosis of ovarian cysts after suspicious US findings. A multiplanar MRI protocol was applied to image and to characterize the cysts. The US and MRI findings were compared, and the prenatal findings were compared with postnatal imaging findings or histopathology. Results: Simple ovarian cysts were found in 10/16 cases and complex cysts in 7/16 cases, including one case with both. In 11/16 (69%) cases, US and MRI diagnoses were in agreement, and, in 5/16 (31%) cases, MRI specified or expanded the US diagnosis. In 6/16 cases, postnatal US showed that the cysts spontaneously resolved or decreased in size, and in 1/16 cases, postnatal imaging confirmed a hemorrhagic cyst. In 4/16 cases, the prenatal diagnoses were confirmed by surgery/histopathology, and for the rest, postnatal correlation was not available. Conclusion: Our results illustrate the MRI visualization of ovarian cysts in utero. In most cases, MRI will confirm the US diagnosis. In certain cases, MRI may provide further diagnostic information, additional to US, which is the standard technique for diagnosis, monitoring, and treatment planning.

Heterologous expression of MlcE in Saccharomyces cerevisiae provides resistance to natural and semi-synthetic statins

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Ana Ley

2015-12-01

Full Text Available Statins are inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A reductase, the key enzyme in cholesterol biosynthesis. Their extensive use in treatment and prevention of cardiovascular diseases placed statins among the best selling drugs. Construction of Saccharomyces cerevisiae cell factory for the production of high concentrations of natural statins will require establishment of a non-destructive self-resistance mechanism to overcome the undesirable growth inhibition effects of statins. To establish active export of statins from yeast, and thereby detoxification, we integrated a putative efflux pump-encoding gene mlcE from the mevastatin-producing Penicillium citrinum into the S. cerevisiae genome. The resulting strain showed increased resistance to both natural statins (mevastatin and lovastatin and semi-synthetic statin (simvastatin when compared to the wild type strain. Expression of RFP-tagged mlcE showed that MlcE is localized to the yeast plasma and vacuolar membranes. We provide a possible engineering strategy for improvement of future yeast based production of natural and semi-synthetic statins. Keywords: Polyketide, Statins, Saccharomyces cerevisiae, Transport, Cell factory, Resistance

Management of ovarian cysts in infants.

Science.gov (United States)

Xue-Qiang, Yan; Nan-Nan, Zheng; Lei, Yu; Wei, Lu; Hong-Qiang, Bian; Jun, Yang; Xu-Fei, Duan; Xin-Ke, Qin

2015-12-01

To discuss the experience of diagnosis and treatment of ovarian cyst in infants. A retrospective review was conducted on 20 infants who suffered from ovarian cyst. There were no dysplasia ovarian was found in children which were preoperatively diagnosed simplex cyst. Within thirteen children preoperatively detected mixed cystic-solid lesion, six cases ovarian cysts disappeared and two cases underwent poor blood supply in the following time. Adverse effects for ovarian cyst in infants can be prevented by agressive surgical intervention. Harmful effects of ovarian cyst can be prevented by positive surgical intervention despite the diagnostic difficulties in children with clinical symptoms of this condition.

Spontaneous hygroma in intracranial arachnoid cyst

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Agnoli, A L

1984-06-01

Anamnesis and treatment of two cases of arachnoid cysts extending into the subarachnoid space are described. No traumatic incident was discovered in the previous history of these two patients. The causal genesis of neurological signs of deficiency in patients with arachnoid and acquired cysts is discussed. However, the cause of the development of a subdural hygroma in arachnoid cysts remains unclarified. CT findings of arachnoid cysts with a hypodense zone between brain surface and the vault of the cranium always require an investigation into the possibility of a spontaneous emptying of the cyst or of a congenital and not only localised extension of the cyst itself.

Percutaneous transcatheter sclerotherapy of oophoritic cysts

International Nuclear Information System (INIS)

Huang Youhua; Xu Qiang; Sun Jun; Shen Tao; Shi Hongjian; Tang Qingfang; Chen Qiying; Zhou Mingxia; Li Hongyao

2005-01-01

Objective: To evaluate the clinical value of percutaneous transcatheter sclerotherapy in oophoritic cysts. Methods: Seventy six oophoritic cysts incluoling 48 simple and 28 chocolate cysts of 64 patients were treated with percutaneous transcatheter sclerotherapy under CT guidance. 4F multisideholes pigtail catheter was introduced into cyst using absolute alcohol as sclerosing agents. Results: The successful rate of percutaneous oophoritc cyst puncture was 100% in all 64 patients. Among them 58 were cured (90.6%), 6 improved significantly (9.4%). The total effective rate reached 100% with no serious complications. Conclusions: Catheterization sclerotherapy for oophoritic cyst is a simple, complete, safe and effective method. (authors)

Odonto calcifying cyst

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Nalini Aswath

2013-01-01

Full Text Available The calcifying odontogenic cyst (COC is reported to be associated with odontoma in 24% of cases. Separation of the cases of calcifying odontogenic cyst associated with odontoma (COCaO may lead to a better understanding of the pathogenesis of this lesion. The literature revealed 52 cases of COCaO. The male to female ratio was 1:1.9, with a mean age of 16 years. Most common location was the maxilla (61.5%. The radiographic appearance of most cases (80.5% was a well-defined, mixed radiolucent-radiopaque lesion. Histologically, the lesions consisted of a single large cyst with tooth-like structures as an integral part, giving the impression of a single lesion. In addition to the unique histologic features, differences in gender and distribution were found between the cases of COCaO and those of simple COC. COCaO may be regarded as a separate entity and classified as a benign, mixed odontogenic tumor. The term odontocalcifying odontogenic cyst is suggested.

Odonto calcifying cyst.

Science.gov (United States)

Aswath, Nalini; Mastan, Kader; Manikandan, Tirupathi; Samuel, Gigi

2013-01-01

The calcifying odontogenic cyst (COC) is reported to be associated with odontoma in 24% of cases. Separation of the cases of calcifying odontogenic cyst associated with odontoma (COCaO) may lead to a better understanding of the pathogenesis of this lesion. The literature revealed 52 cases of COCaO. The male to female ratio was 1:1.9, with a mean age of 16 years. Most common location was the maxilla (61.5%). The radiographic appearance of most cases (80.5%) was a well-defined, mixed radiolucent-radiopaque lesion. Histologically, the lesions consisted of a single large cyst with tooth-like structures as an integral part, giving the impression of a single lesion. In addition to the unique histologic features, differences in gender and distribution were found between the cases of COCaO and those of simple COC. COCaO may be regarded as a separate entity and classified as a benign, mixed odontogenic tumor. The term odontocalcifying odontogenic cyst is suggested.

A giant traumatic iris cyst

Directory of Open Access Journals (Sweden)

Lott Pooi Wah

2015-12-01

Full Text Available A 52 year-old construction worker presented with progressive painful blurring of vision in the left eye associated with redness for past 1 month. There was a history of penetrating injury in the same eye 10 years ago and he underwent primary wound toilet and suturing, lens removal with intraocular lens implantation. Slit lamp examination revealed a corneal scar at 9’oclock, a large transilluminant iris cyst superotemporally and adherent to corneal endothelium. It was extended from angle of the pupil and obstructing the visual axis. The patient underwent excision of an iris cyst through superior limbal incision. Viscodissection was done to separate the cyst from the corneal endothelium and underlying iris stroma. Trypan blue ophthalmic solution was injected into the cyst to stain the cyst capsule. Post operatively 7 days, vision improved to 6/7.5 without complication. There was no recurrence up to 1 year postoperation. Histopathological finding revealed a benign cyst mass lined by simple cuboidal to nonkeratinized stratified squamous epithelium. We had achieved a good surgical outcome with no complication to date for our case study. We advocate this modified surgical method to completely remove iris cyst.

A simple hepatic cyst with elevated serum and cyst fluid CA19-9 levels: a case report

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Yanai Hidekatsu

2008-10-01

Full Text Available Abstract Introduction Simple hepatic cysts rarely cause symptoms, however, occasionally they become symptomatic due to mass effect, rupture, hemorrhage, and infection. We report a patient with a large hepatic cyst with elevated serum and cyst fluid CA19-9 levels. We studied serum and cyst fluid CA19-9 levels in this patient, before and after the intracystic instillation of minocycline hydrochloride. Case presentation A 76-year-old Japanese woman was diagnosed as having an infected hepatic cyst, by physical examination and enhanced abdominal computed tomography. Serum (170 U/ml; reference: Conclusion Our study is the first report to reveal the influence of intracystic instillation of minocycline hydrochloride on serum and cyst fluid CA19-9 levels in a patient with a simple hepatic cyst.

A study on radicular cysts of primary teeth mimicking dentigerous cysts

International Nuclear Information System (INIS)

Cho, Bong Hae; Nah, Kyung Soo

1994-01-01

20 radicular cysts of primary teeth mimicking dentigerous cyst were reviewed. The following results were obtained. 1. The patients' age ranged from 7 to 14 years. Males(60%) were more involved than females (40%). 2. The mandible (85%) was affected more frequently than the maxilla (15%). The mandibular deciduous molar area (80%) was the most frequently involved. 3. The diameter of the cyst varied from 10 to 30 mm. 55% of permanent successors showed underdeveloped roots less than one-third. 4. The etiologic factors were pulp-treated teeth (65%), severe caries (20%), trauma (10%), deep amalgam filling (5%).

Hydatid Cyst of Ovary: A Case Report

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Mohsen Khosravi Maharlooei

2009-03-01

Full Text Available Echinococcus granulosus is considered the major cause of humanhydatid cysts. Usually the duration of cyst formation is 10-20 years. This period shortens significantly upon rupture of aprimary cyst. The literature describes low incidence of primaryinvolvement of ovary as a site of hydatid cyst formation. Ourcase is the first report on ovarian hydatid cyst in Iran. A 60-year-old woman was presented with abdominal pain in the leftlower quadrant area. Paraclinical data were suggestive of neoplasiaand preoperative diagnosis was ovarian tumor. Duringlaparotomy, multiple cysts resembling hydatid cysts were observedin the left ovary. Pathological examination confirmed thediagnosis of hydatid cyst. Although there is a small possibilityof secondary ovarian echinococcal disease, it is more probablefor this case to be primary infection, as the patient had developedovarian hydatid cysts 15 years after hepatic involvementand recurrence after 30 months is very uncommon.

Hydatid cyst of mediastinum

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Sehgal S

2008-01-01

Full Text Available We report a case of hydatid cyst of the mediastinum in a 32-year-old female patient who was admitted with chest pain. CT scan reported posterior mediastinal mass towards the right side. Surgical exploration revealed a loculated cyst in posterior mediastinum on the right side, adherent to the overlying lung and underlying bone. Posterolateral thoracotomy was performed for cyst aspiration and excision. The patient was discharged on albendazole.

(unicameral) bone cysts

African Journals Online (AJOL)

SA JOURNAL OF RADIOLOGY • September 2007. When encountering a radiologically benign lucent bone lesion in a child, a simple bone cyst is a reasonable diagnostic consideration. Simple or unicameral bone cysts are expansile, serous-fluid-containing defects, that are not true neoplasms. Peak age ranges between 3 ...

Expression of cytokeratins in odontogenic jaw cysts: monoclonal antibodies reveal distinct variation between different cyst types.

Science.gov (United States)

Hormia, M; Ylipaavalniemi, P; Nagle, R B; Virtanen, I

1987-08-01

Immunostaining with monoclonal antibodies was used to study and compare the cytokeratin content of odontogenic cysts and normal gingival epithelium. Two monoclonal antibodies, PKK2 and KA1, stained the whole epithelium in all cyst samples. In gingiva, PKK2 gave a suprabasal staining and KA1 reacted with all epithelial cell layers. Antibodies PKK1, KM 4.62 and KS 8.12 gave a heterogeneous staining in follicular and radicular cysts. In keratocysts and in gingiva PKK1 and KM 4.62 reacted mainly with basal cells and KS 8.12 gave a suprabasal staining. Antibodies reacting with the simple epithelial cytokeratin polypeptide No. 18 (PKK3, KS 18.18) recognized in gingiva only solitary cells compatible with Merkel cells. In a case of follicular ameloblastoma a distinct staining of tumor epithelium was revealed with these antibodies. In 2 follicular cysts, but not in other cyst types, a layer of cytokeratin 18-positive cells was revealed. KA5 and KK 8.60 antibodies, reacting exclusively with keratinizing epithelia, including normal gingiva, gave no reaction in radicular cysts, keratocysts and ameloblastoma. Two of the follicular cysts, were negative for PKK3 and KS 18.18, but reacted strongly with KA5 and KK 8.60. The present results show that odontogenic jaw cysts have distinct differences in their cytokeratin content. With the exception of some follicular cysts, they lack signs of keratinizing epithelial differentiation. Only follicular cysts appear to share with some types of ameloblastoma the expression of cytokeratin polypeptide No. 18.

Case Report: CT diagnosis of thymic remnant cyst/thymopharyngeal duct cyst

International Nuclear Information System (INIS)

Daga, Bipin V; Chaudhary, VA; Dhamangaokar, VB

2009-01-01

A 4-year-old boy presented with history of left anterolateral neck swelling since birth. He was clinically diagnosed to have a branchial cleft cyst. A CT scan revealed findings suggestive of a thymic remnant cyst. The lesion was excised and the diagnosis was confirmed by histopathology

Aspiration sclerotherapy of hepatic cysts

NARCIS (Netherlands)

Wijnands, T.F.M.

2017-01-01

Hepatic cysts are fluid-filled lesions in the liver that generally arise as congenital anomalies. Prevalence is estimated between 3 and 18%. Overall, cysts are benign and asymptomatic. However, hepatic cysts can increase to a volume of several liters as a result of continuous fluid production by the

Management of ovarian cysts in infants

Directory of Open Access Journals (Sweden)

Yan Xue-qiang

2015-01-01

Full Text Available Background: To discuss the experience of diagnosis and treatment of ovarian cyst in infants. Materials and Methods: A retrospective review was conducted on 20 infants who suffered from ovarian cyst. Results: There were no dysplasia ovarian was found in children which were preoperatively diagnosed simplex cyst. Within thirteen children preoperatively detected mixed cystic-solid lesion, six cases ovarian cysts disappeared and two cases underwent poor blood supply in the following time. Conclusion: Adverse effects for ovarian cyst in infants can be prevented by agressive surgical intervention. Harmful effects of ovarian cyst can be prevented by positive surgical intervention despite the diagnostic difficulties in children with clinical symptoms of this condition.

Validation of Varian TrueBeam electron phase–spaces for Monte Carlo simulation of MLC-shaped fields

Energy Technology Data Exchange (ETDEWEB)

Lloyd, Samantha A. M. [Department of Physics and Astronomy, University of Victoria, Victoria, British Columbia V8P 3P6 5C2 (Canada); Gagne, Isabelle M., E-mail: imgagne@bccancer.bc.ca; Zavgorodni, Sergei [Department of Medical Physics, BC Cancer Agency–Vancouver Island Centre, Victoria, British Columbia V8R 6V5, Canada and Department of Physics and Astronomy, University of Victoria, Victoria, British Columbia V8W 3P6 5C2 (Canada); Bazalova-Carter, Magdalena [Department of Physics and Astronomy, University of Victoria, Victoria, British Columbia V8W 3P6 5C2 (Canada)

2016-06-15

Purpose: This work evaluates Varian’s electron phase–space sources for Monte Carlo simulation of the TrueBeam for modulated electron radiation therapy (MERT) and combined, modulated photon and electron radiation therapy (MPERT) where fields are shaped by the photon multileaf collimator (MLC) and delivered at 70 cm SSD. Methods: Monte Carlo simulations performed with EGSnrc-based BEAMnrc/DOSXYZnrc and PENELOPE-based PRIMO are compared against diode measurements for 5 × 5, 10 × 10, and 20 × 20 cm{sup 2} MLC-shaped fields delivered with 6, 12, and 20 MeV electrons at 70 cm SSD (jaws set to 40 × 40 cm{sup 2}). Depth dose curves and profiles are examined. In addition, EGSnrc-based simulations of relative output as a function of MLC-field size and jaw-position are compared against ion chamber measurements for MLC-shaped fields between 3 × 3 and 25 × 25 cm{sup 2} and jaw positions that range from the MLC-field size to 40 × 40 cm{sup 2}. Results: Percent depth dose curves generated by BEAMnrc/DOSXYZnrc and PRIMO agree with measurement within 2%, 2 mm except for PRIMO’s 12 MeV, 20 × 20 cm{sup 2} field where 90% of dose points agree within 2%, 2 mm. Without the distance to agreement, differences between measurement and simulation are as large as 7.3%. Characterization of simulated dose parameters such as FWHM, penumbra width and depths of 90%, 80%, 50%, and 20% dose agree within 2 mm of measurement for all fields except for the FWHM of the 6 MeV, 20 × 20 cm{sup 2} field which falls within 2 mm distance to agreement. Differences between simulation and measurement exist in the profile shoulders and penumbra tails, in particular for 10 × 10 and 20 × 20 cm{sup 2} fields of 20 MeV electrons, where both sets of simulated data fall short of measurement by as much as 3.5%. BEAMnrc/DOSXYZnrc simulated outputs agree with measurement within 2.3% except for 6 MeV MLC-shaped fields. Discrepancies here are as great as 5.5%. Conclusions: TrueBeam electron phase�

High-Dose Spatially Fractionated GRID Radiation Therapy (SFGRT): A Comparison of Treatment Outcomes With Cerrobend vs. MLC SFGRT

International Nuclear Information System (INIS)

Neuner, Geoffrey; Mohiuddin, Majid M.; Vander Walde, Noam; Goloubeva, Olga; Ha, Jonathan; Yu, Cedric X.; Regine, William F.

2012-01-01

Purpose: Spatially fractionated GRID radiotherapy (SFGRT) using a customized Cerrobend block has been used to improve response rates in patients with bulky tumors. The clinical efficacy of our own multileaf collimator (MLC) technique is unknown. We undertook a retrospective analysis to compare clinical response rates attained using these two techniques. Methods and Materials: Seventy-nine patients with bulky tumors (median diameter, 7.6 cm; range, 4–30 cm) treated with SFGRT were reviewed. Between 2003 and late 2005, the Cerrobend block technique (n = 39) was used. Between late 2005 and 2008, SFGRT was delivered using MLC-shaped fields (n = 40). Dose was prescribed to dmax (depth of maximum dose) and was typically 15 Gy. Eighty percent of patients in both groups received external beam radiotherapy in addition to SFGRT. The two-sided Fisher-Freeman-Halton test was used to compare pain and mass effect response rates between the two groups. Results: Sixty-one patients (77%) were treated for palliative intent and 18 (23%) for curative intent. The majority of patients had either lung or head-and-neck primaries in both groups; the most frequent site of SFGRT application was the neck. The majority of patients complained of either pain (65%) or mass effect (58%) at intake. Overall response rates for pain and mass response were no different between the Cerrobend and MLC groups: pain, 75% and 74%, respectively (p = 0.50), and mass effect, 67% and 73%, respectively (p = 0.85). The majority of toxicities were Grade 1 or 2, and only 3 patients had late Grade 3-4 toxicities. Conclusions: MLC-based and Cerrobend-based SFGRT have comparable and encouraging response rates when used either in the palliative or curative setting. MLC-based SGFRT should allow clinics to more easily adopt this novel treatment approach for the treatment of bulky tumors.

SU-E-T-114: Analysis of MLC Errors On Gamma Pass Rates for Patient-Specific and Conventional Phantoms

Energy Technology Data Exchange (ETDEWEB)

Sterling, D; Ehler, E [University of Minnesota, Minneapolis, MN (United States)

2015-06-15

Purpose: To evaluate whether a 3D patient-specific phantom is better able to detect known MLC errors in a clinically delivered treatment plan than conventional phantoms. 3D printing may make fabrication of such phantoms feasible. Methods: Two types of MLC errors were introduced into a clinically delivered, non-coplanar IMRT, partial brain treatment plan. First, uniformly distributed random errors of up to 3mm, 2mm, and 1mm were introduced into the MLC positions for each field. Second, systematic MLC-bank position errors of 5mm, 3.5mm, and 2mm due to simulated effects of gantry and MLC sag were introduced. The original plan was recalculated with these errors on the original CT dataset as well as cylindrical and planar IMRT QA phantoms. The original dataset was considered to be a perfect 3D patient-specific phantom. The phantoms were considered to be ideal 3D dosimetry systems with no resolution limitations. Results: Passing rates for Gamma Index (3%/3mm and no dose threshold) were calculated on the 3D phantom, cylindrical phantom, and both on a composite and field-by-field basis for the planar phantom. Pass rates for 5mm systematic and 3mm random error were 86.0%, 89.6%, 98% and 98.3% respectively. For 3.5mm systematic and 2mm random error the pass rates were 94.7%, 96.2%, 99.2% and 99.2% respectively. For 2mm systematic error with 1mm random error the pass rates were 99.9%, 100%, 100% and 100% respectively. Conclusion: A 3D phantom with the patient anatomy is able to discern errors, both severe and subtle, that are not seen using conventional phantoms. Therefore, 3D phantoms may be beneficial for commissioning new treatment machines and modalities, patient-specific QA and end-to-end testing.

SU-E-T-114: Analysis of MLC Errors On Gamma Pass Rates for Patient-Specific and Conventional Phantoms

International Nuclear Information System (INIS)

Sterling, D; Ehler, E

2015-01-01

Purpose: To evaluate whether a 3D patient-specific phantom is better able to detect known MLC errors in a clinically delivered treatment plan than conventional phantoms. 3D printing may make fabrication of such phantoms feasible. Methods: Two types of MLC errors were introduced into a clinically delivered, non-coplanar IMRT, partial brain treatment plan. First, uniformly distributed random errors of up to 3mm, 2mm, and 1mm were introduced into the MLC positions for each field. Second, systematic MLC-bank position errors of 5mm, 3.5mm, and 2mm due to simulated effects of gantry and MLC sag were introduced. The original plan was recalculated with these errors on the original CT dataset as well as cylindrical and planar IMRT QA phantoms. The original dataset was considered to be a perfect 3D patient-specific phantom. The phantoms were considered to be ideal 3D dosimetry systems with no resolution limitations. Results: Passing rates for Gamma Index (3%/3mm and no dose threshold) were calculated on the 3D phantom, cylindrical phantom, and both on a composite and field-by-field basis for the planar phantom. Pass rates for 5mm systematic and 3mm random error were 86.0%, 89.6%, 98% and 98.3% respectively. For 3.5mm systematic and 2mm random error the pass rates were 94.7%, 96.2%, 99.2% and 99.2% respectively. For 2mm systematic error with 1mm random error the pass rates were 99.9%, 100%, 100% and 100% respectively. Conclusion: A 3D phantom with the patient anatomy is able to discern errors, both severe and subtle, that are not seen using conventional phantoms. Therefore, 3D phantoms may be beneficial for commissioning new treatment machines and modalities, patient-specific QA and end-to-end testing

SU-F-T-303: Quantification of MLC Positioning Accuracy in VMAT Delivery of Head and Neck Cancer Treatment

Energy Technology Data Exchange (ETDEWEB)

Li, X; Yang, F [University Of Miami, Miami, FL (United States)

2016-06-15

Purpose: Knowing MLC leaf positioning error over the course of treatment would be valuable for treatment planning, QA design, and patient safety. The objective of the current study was to quantify the MLC positioning accuracy for VMAT delivery of head and neck treatment plans. Methods: A total of 837 MLC log files were collected from 14 head and neck cancer patients undergoing full arc VMAT treatment on one Varian Trilogy machine. The actual and planned leaf gaps were extracted from the retrieved MLC log files. For a given patient, the leaf gap error percentage (LGEP), defined as the ratio of the actual leaf gap over the planned, was evaluated for each leaf pair at all the gantry angles recorded over the course of the treatment. Statistics describing the distribution of the largest LGEP (LLGEP) of the 60 leaf pairs including the maximum, minimum, mean, Kurtosis, and skewness were evaluated. Results: For the 14 studied patients, their PTV located at tonsil, base of tongue, larynx, supraglottis, nasal cavity, and thyroid gland with volume ranging from 72.0 cm{sup 3} to 602.0 cm{sup 3}. The identified LLGEP differed between patients. It ranged from 183.9% to 457.7% with a mean of 368.6%. For the majority of the patients, the LLGEP distributions peaked at non-zero positions and showed no obvious dependence on gantry rotations. Kurtosis and skewness, with minimum/maximum of 66.6/217.9 and 6.5/12.6, respectively, suggested relatively more peaked while right-skewed leaf error distribution pattern. Conclusion: The results indicate pattern of MLC leaf gap error differs between patients of lesion located at similar anatomic site. Understanding the systemic mechanisms underlying these observed error patterns necessitates examining more patient-specific plan parameters in a large patient cohort setting.

Chrysophyte cysts as potential environmental indicators

Science.gov (United States)

Adam, David P.; Mahood, Albert D.

1981-01-01

Many Chrysophyte algae produce morphologically distinctive, siliceous, microscopic cysts during a resting stage of their life cycles; these cysts are often preserved in sediments. Scanning electron microscopy and Nomarski optics permit much more detailed observation of these cysts than was heretofore possible. We have used an ecologic and biogeographic approach to study the distribution of cyst forms in sediments and have established that many cyst types are found only in specific habitats, such as montane lakes, wet meadows, ephemeral ponds, and Sphagnum bogs. In the samples we have studied, cysts seem to be most common in fluctuating fresh-water habitats of low to moderate pH and some winter freezing. Numerous taxonomic problems have yet to be resolved. We believe that chrysophyte cysts have the potential to become a useful tool for both modern environmental assessments and paleoecological studies of Cenozoic fresh-water lacustrine deposits.

Liver Hydatid Cyst with Transdiaphragmatic Rupture and Lung Hydatid Cyst Ruptured into Bronchi and Pleural Space

International Nuclear Information System (INIS)

Arıbaş, Bilgin Kadri; Dingil, Gürbüz; Köroğlu, Mert; Üngül, Ümit; Zaralı, Aliye Ceylan

2011-01-01

The aim of this case study is to present effectiveness of percutaneous drainage as a treatment option of ruptured lung and liver hydatid cysts. A 65-year-old male patient was admitted with complicated liver and lung hydatid cysts. A liver hydatid cyst had ruptured transdiaphragmatically, and a lung hydatid cyst had ruptured both into bronchi and pleural space. The patient could not undergo surgery because of decreased respiratory function. Both cysts were drained percutaneously using oral albendazole. Povidone–iodine was used to treat the liver cyst after closure of the diaphragmatic rupture. The drainage was considered successful, and the patient had no recurrence of signs and symptoms. Clinical, laboratory, and radiologic recovery was observed during 2.5 months of catheterization. The patient was asymptomatic after catheter drainage. No recurrence was detected during 86 months of follow-up. For inoperable patients with ruptured liver and lung hydatid cysts, percutaneous drainage with oral albendazole is an alternative treatment option to surgery. The percutaneous approach can be life-saving in such cases.

CT diagnosis of simple renal cysts

International Nuclear Information System (INIS)

Nanakawa, Seito; Yasunaga, Tadamasa; Tsuchigame, Tadatoshi; Kawano, Shoji; Takahashi, Mutsumasa; Fukui, Koutaro.

1987-01-01

CT is indispensable in the evaluation of renal masses, providing noninvasive and clear transverse images. With wider clinical application of CT, renal cysts have been found more frequently. CT examinations on 500 patients, who underwent CT for the diagnosis of renal diseases except for renal cysts, have been reviewed and analysed. The incidence of renal cysts was 9.6 % without prediction for sexes, but the incidence and sizes of the cysts increased with the advancing age. The upper portion of the kidneys was more frequently involved, but there was no relationship between number, sex and age of the patients. Since renal cysts produce mass effect in the kidneys, understanding of the nature and incidence of the renal cysts is important in diagnosing renal mass lesions. (author)

[Subcortical laminar heterotopia 'double cortex syndrome'].

Science.gov (United States)

Teplyshova, A M; Gaskin, V V; Kustov, G V; Gudkova, A A; Luzin, R V; Trifonov, I S; Lebedeva, A V

2017-01-01

This article presents a clinical case of a 29-year-old patient with 'Double cortex syndrome' with epilepsy, intellectual and mental disorders. Subcortical band heterotopia is a rare disorder of neuronal migration. Such patients typically present with epilepsy and variable degrees of mental retardation and behavioral and intellectual disturbances. The main diagnostic method is magnetic resonance imaging (MRI).

Congenital cervical bronchogenic cyst: A case report

Directory of Open Access Journals (Sweden)

Kiralj Aleksandar

2015-01-01

Full Text Available Introduction. Bronchogenic cysts are rare congenital anomalies of the embryonic foregut. They are caused by abnormal budding of diverticulum of the embryonic foregut between the 26th and 40th day of gestation. Bronchogenic cysts can appear in the mediastinum and pulmonary parenchyma, or at ectopic sites (neck, subcutaneous tissue or abdomen. So far, 70 cases of cervical localization of bronchogenic cysts have been reported. Majority of bronchogenic cysts have been diagnosed in the pediatric population. Bronchogenic cysts of the cervical area are generally asymptomatic and symptoms may occur if cysts become large or in case of infection of the cyst. The diagnosis is made based on clinical findings, radiological examination, but histopathologic findings are essential for establishing the final diagnosis. Treatment of cervical bronchogenic cyst involves surgical excision. Case Outline. Authors present a case of a 6-year-old female patient sent by a pediatrician to a maxillofacial surgeon due to asymptomatic lump on the left side of the neck. The patient had frequent respiratory infections and respiratory obstructions. Magnetic resonance imaging (MRI of the neck was performed and a well-circumscribed cystic formation on the left side of the neck was observed, with paratracheal location. The complete excision of the cyst was made transcervically. Histopathological findings pointed to bronchogenic cyst. Conclusion. Cervical bronchogenic cysts are rare congenital malformations. Considering the location, clinical findings and the radiological features, these cysts resemble other cervical lesions. Surgical treatment is important because it is both therapeutic and diagnostic. Reliable diagnosis of bronchogenic cysts is based on histopathological examination.

Management Strategy for Unicameral Bone Cyst

Directory of Open Access Journals (Sweden)

Chin-Yi Chuo

2003-06-01

Full Text Available The management of a unicameral bone cyst varies from percutaneous needle biopsy, aspiration, and local injection of steroid, autogenous bone marrow, or demineralized bone matrix to the more invasive surgical procedures of conventional curettage and grafting (with autogenous or allogenous bone or subtotal resection with bone grafting. The best treatment for a unicameral bone cyst is yet to be identified. Better understanding of the pathology will change the concept of management. The aim of treatment is to prevent pathologic fracture, to promote cyst healing, and to avoid cyst recurrence and re-fracture. We retrospectively reviewed 17 cases of unicameral bone cysts (12 in the humerus, 3 in the femur, 2 in the fibula managed by conservative observation, curettage and bone grafting with open reduction and internal fixation, or continuous decompression and drainage with a cannulated screw. We suggest percutaneous cannulated screw insertion to promote cyst healing and prevent pathologic fracture. We devised a protocol for the management of unicameral bone cysts.

Management strategy for unicameral bone cyst.

Science.gov (United States)

Chuo, Chin-Yi; Fu, Yin-Chih; Chien, Song-Hsiung; Lin, Gau-Tyan; Wang, Gwo-Jaw

2003-06-01

The management of a unicameral bone cyst varies from percutaneous needle biopsy, aspiration, and local injection of steroid, autogenous bone marrow, or demineralized bone matrix to the more invasive surgical procedures of conventional curettage and grafting (with autogenous or allogenous bone) or subtotal resection with bone grafting. The best treatment for a unicameral bone cyst is yet to be identified. Better understanding of the pathology will change the concept of management. The aim of treatment is to prevent pathologic fracture, to promote cyst healing, and to avoid cyst recurrence and re-fracture. We retrospectively reviewed 17 cases of unicameral bone cysts (12 in the humerus, 3 in the femur, 2 in the fibula) managed by conservative observation, curettage and bone grafting with open reduction and internal fixation, or continuous decompression and drainage with a cannulated screw. We suggest percutaneous cannulated screw insertion to promote cyst healing and prevent pathologic fracture. We devised a protocol for the management of unicameral bone cysts.

MR imaging of pineal cysts

International Nuclear Information System (INIS)

Ahn, Yong Sik; Yu, Hyeon; Kim, Wan Tae; Bae, Jin Woo; Moon, Hee Jung; Shin, Hyun Ja

1999-01-01

To evaluate the incidence and characteristic findings of pineal cyst incidentally detected on magnetic resonance (MR) imaging. Brain MR images obtained in 2432 patients were retrospectively reviewed to determine the incidence and MR findings of pineal cysts, which were evaluated according to their size, shape, location, signal intensity, interval change, contrast enhancement and mass effect on adjacent structures. Cysts were encountered in 107(4.4 %) of 2432 patients evaluated. their size ranged from 1 X 1 X 1 to 15 X 8 X 9 (mean, 5.97 X 3.82 X 4.82)mm. All were spherical (n=53) or oval (n=54) in shape. Their margin was smooth and they were homogeneous in nature. On T1-weighted images, the cysts were seen to be hyperintense (n=57) or isointense (n=50) to cerebrospinal fluid, but less so than brain parenchyma. T2-weighted images showed them to be isointense (n=51)or hyperintense (n=56) to cerebrospinal fluid. The cysts were centrally located in 65 cases and eccentrically in 42. Compression of the superior colliculi of the tectum was demonstrated in 17 cases (15.9 %). NO patients presented clinical symptoms or signs related to either pineal or tectal lesions. Peripheral enhancement around the cyst after Gd-DTPA injection was demonstrated in 51 cases(100 %). Follow-up examinations in 19 cases demonstrated no interval change. The incidence of pineal cysts was 4.4 %. The MR characteristics of simple pineal cysts include: (1) an oval or spherical shape, (2) a smooth outer margin and homogeneous nature, (3) isosignal or slightly high signal intensity to cerebrospinal fluid on whole pulse sequences, (4) ring enhancement after contrast injection, (5) an absence of interval change, as seen during follow up MR study. These MR appearances of pineal cysts might be helpful for differentiating them from pineal tumors

Infected orbital cyst following exenteration.

Science.gov (United States)

Barak, A; Hirsh, A; Rosner, M; Rosen, N

1996-09-01

An orbital cyst is a rare complication of orbital trauma and exenteration. Infections of such cysts have not been described, and are potentially dangerous unless treated immediately. The authors describe a case of delayed treatment of such an infected cyst, which resolved following surgical drainage. The potentially hazardous outcome makes knowledge of such cases important.

Solitary (unicameral) bone cyst

International Nuclear Information System (INIS)

Struhl, S.; Edelson, C.; Pritzker, H.; Seimon, L.P.; Dorfman, H.D.; Montefiore Medical Center, Bronx, NY

1989-01-01

The fallen fragment sign is a prominent radiologic feature in a minority of cases of unicameral bone cyst (20% in this series). This sign is always associated with pathologic fracture. Intramedullary fracture fragments may be single or multiple and may or may not be entirely dislodged from overlying periosteum. The finding appears limited to unicameral bone cysts in patients with open physes. When present, the fallen fragment is a pathognomonic finding as it defines the interior of the cyst as nonsolid. (orig./GDG)

Spinal Extradural Arachnoid Cyst

OpenAIRE

Choi, Seung Won; Seong, Han Yu; Roh, Sung Woo

2013-01-01

Spinal extradural arachnoid cyst (SEAC) is a rare disease and uncommon cause of compressive myelopathy. The etiology remains still unclear. We experienced 2 cases of SEACs and reviewed the cases and previous literatures. A 59-year-old man complained of both leg radiating pain and paresthesia for 4 years. His MRI showed an extradural cyst from T12 to L3 and we performed cyst fenestration and repaired the dural defect with tailored laminectomy. Another 51-year-old female patient visited our cli...

Dynamic-MLC leaf control utilizing on-flight intensity calculations: A robust method for real-time IMRT delivery over moving rigid targets

International Nuclear Information System (INIS)

McMahon, Ryan; Papiez, Lech; Rangaraj, Dharanipathy

2007-01-01

An algorithm is presented that allows for the control of multileaf collimation (MLC) leaves based entirely on real-time calculations of the intensity delivered over the target. The algorithm is capable of efficiently correcting generalized delivery errors without requiring the interruption of delivery (self-correcting trajectories), where a generalized delivery error represents anything that causes a discrepancy between the delivered and intended intensity profiles. The intensity actually delivered over the target is continually compared to its intended value. For each pair of leaves, these comparisons are used to guide the control of the following leaf and keep this discrepancy below a user-specified value. To demonstrate the basic principles of the algorithm, results of corrected delivery are shown for a leading leaf positional error during dynamic-MLC (DMLC) IMRT delivery over a rigid moving target. It is then shown that, with slight modifications, the algorithm can be used to track moving targets in real time. The primary results of this article indicate that the algorithm is capable of accurately delivering DMLC IMRT over a rigid moving target whose motion is (1) completely unknown prior to delivery and (2) not faster than the maximum MLC leaf velocity over extended periods of time. These capabilities are demonstrated for clinically derived intensity profiles and actual tumor motion data, including situations when the target moves in some instances faster than the maximum admissible MLC leaf velocity. The results show that using the algorithm while calculating the delivered intensity every 50 ms will provide a good level of accuracy when delivering IMRT over a rigid moving target translating along the direction of MLC leaf travel. When the maximum velocities of the MLC leaves and target were 4 and 4.2 cm/s, respectively, the resulting error in the two intensity profiles used was 0.1±3.1% and -0.5±2.8% relative to the maximum of the intensity profiles. For

Characterization of megavoltage electron beams delivered through a photon multi-leaf collimator (pMLC)

Energy Technology Data Exchange (ETDEWEB)

Plessis, F C P du; Leal, A; Stathakis, S; Xiong, W; Ma, C-M [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA 19111 (United States)

2006-04-21

A study is presented that characterizes megavoltage electron beams delivered through an existing double-focused photon multi-leaf collimator (pMLC) using film measurements in a solid water phantom. Machine output stability and linearity were evaluated as well as the effect of source-to-surface distance (SSD) and field size on the penumbra for electron energies between 6 and 18 MeV over an SSD range of 60-100 cm. Penumbra variations as a function of field size, depth of measurement and the influence of the jaws were also studied. Field abutment, field flatness and target coverage for segmented beams were also addressed. The measured field size for electrons transported through the pMLC was the same as that for an x-ray beam up to SSDs of 70 cm. At larger SSD, the lower energy electron fields deviated from the projected field. Penumbra data indicated that 60 cm SSD was the most favourable treatment distance. Backprojection of P{sub 20-80} penumbra data yielded a virtual source position located at 98.9 cm from the surface for 18 MeV electrons. For 6 MeV electrons, the virtual source position was at a distance of 82.6 cm. Penumbra values were smaller for small beam slits and reached a near-constant value for field widths larger than 5 cm. The influence of the jaws had a small effect on the penumbra. The R{sub 90} values ranged from 1.4 to 4.8 cm between 6 and 21 MeV as measured at 60 cm SSD for a 9 x 9 cm{sup 2} field. Uniformity and penumbra improvement could be demonstrated using weighted abutted fields especially useful for small segments. No detectable electron leakage through the pMLC was observed. Bremsstrahlung measurements taken at 60 cm SSD for a 9 x 9 cm{sup 2} field as shaped by the pMLC compared within 1% to bremsstrahlung measurements taken at 100 cm SSD for a 10 x 10 cm{sup 2} electron applicator field at 100 cm SSD.

SU-G-JeP1-05: Clinical Impact of MLC Tracking for Lung SABR

Energy Technology Data Exchange (ETDEWEB)

Caillet, V; Colvill, E [Faculty of Medecine, The University of Sydney, Sydney, NSW (Australia); Royal North Shore Hospital, Sydney, NSW (Australia); Szymura, K; Stevens, M; Booth, J [Royal North Shore Hospital, Sydney, NSW (Australia); Keall, P [Faculty of Medecine, The University of Sydney, Sydney, NSW (Australia)

2016-06-15

Purpose: The objective of this study was to investigate the dosimetric benefits of multi-leaf collimator (MLC) tracking for lung SABR treatments in end-to-end clinically realistic planning and delivery scenarios. Methods: The clinical benefits of MLC tracking were assessed using previously delivered treatment plans and physical experiments. The 10 most recent single lesion lung SABR patients were re-planned following a 4D-GTV-based real-time adaptive protocol (PTV defined as the end-of-exhalation GTV plus 5.0 mm margins). The plans were delivered on a Trilogy Varian linac. Electromagnetic transponders (Calypso, Varian Medical Systems, USA) were embedded into a programmable moving phantom (HexaMotion platform) tracked with the Varian Calypso system. For each physical experiment, the MLC positions were collected and used as input for dose reconstruction. For both planned and physical experiments, the OAR dose metrics from the conventional and real-time adaptive SABR plans (Mean Lung Dose (MLD), V20 for lung, and near-maximum dose (D2%) for spine and heart) were statistically compared. The Wilcoxon test was used to compare plan and physical experiment dose metrics. Results: While maintaining target coverage, percentage reductions in dose metrics to the OARs were observed for both planned and physical experiments. Comparing the two plans showed MLD percentage reduction (MLDr) of 25.4% (absolute differences of 1.41 Gy) and 28.9% (1.29%) for the V20r. D2% percentage reduction for spine and heart were respectively 27.9% (0.3 Gy) and 20.2% (0.3 Gy). For the physical experiments, MLDr was 23.9% (1.3 Gy), and V20r 37.4% (1.6%). D2% reduction for spine and heart were respectively 27.3% (0.3 Gy) and 19.6% (0.3 Gy). For both plans and physical experiments, significant OAR dose differences (p<0.05) were found between the conventional SABR and real-time adaptive plans. Conclusion: Application of MLC tracking for lung SABR patients has the potential to reduce the dose to OARs

Imaging of the jaw cysts with a dental CT software program : distinction of odontogenic keratocysts from other cysts

International Nuclear Information System (INIS)

Lee, Jung Man; Shin, Sang Hoon; Lee, Won Hoon; Oh, Kyu Hyen; Jung, Hak Young; Lee, Young Hwan; Sung, Nak Kwan; Jung, Duck Soo; Kim, Ok Dong

1997-01-01

To evaluate the usefulness of a dental CT software program in the assessment of jaw cysts and in the differentiation of odontogenic keratocysts and other cysts. Seventeen patients with proven jaw cysts(8 maxillae and 9 mandibles) were evaluated with a dental CT sofware program for location, locularity, the presence or absence of marginal scallping, and height to length ratio. For the delineation of involvement or displace-ment of neurovascular bundles, cortical erosion, perforation or expansion, and tooth root resorption by the jaw cysts, images from this program were compared to conventional images. Seventeen lesions icomprised 15 odontogenic cysts (five odontogenic keratocysts, five radicular, three residual and two dentigerous cysts) and two non-odontogenic cysts (one nasopalatine duct cyst and one postoperative maxillary cyst). Images of jaw cysts obtained with the dental CT software program delineated much more clearly than conventional images the status of neurovascular bundle and cortical bone, but there was no clear difference between the two modalities in delineating tooth root erosion. Dental CT findings of five mandibular odontogenic keratocysts were scalloped margin in all, mandibular ramus involvement in four, height to length ratio below 60% in four ,and multilocularity in two. The findings of the other 12 cysts (eight maxillae and four mandibles) were unilocularity in all, smooth inner margin in ten, height to length ratio below 60% in only two, and ramus involvement in none. A dental CT software program is an improved imaging modality for assessing jaw cysts;and findings which tend to indicate odontogenic keratocysts are marginal scalloping, mandibular ramus involvement, prominent spread along the marrow space and multilocularity

An MLC-based linac QA procedure for the characterization of radiation isocenter and room lasers' position

International Nuclear Information System (INIS)

Rosca, Florin; Lorenz, Friedlieb; Hacker, Fred L.; Chin, Lee M.; Ramakrishna, Naren; Zygmanski, Piotr

2006-01-01

We have designed and implemented a new stereotactic linac QA test with stereotactic precision. The test is used to characterize gantry sag, couch wobble, cone placement, MLC offsets, and room lasers' positions relative to the radiation isocenter. Two MLC star patterns, a cone pattern, and the laser line patterns are recorded on the same imaging medium. Phosphor plates are used as imaging medium due to their sensitivity to red light. The red light of room lasers erases some of the irradiation information stored on the phosphor plates enabling accurate and direct measurements for the position of room lasers and radiation isocenter. Using film instead of the phosphor plate as imaging medium is possible, however, it is less practical. The QA method consists of irradiating four phosphor plates that record the gantry sag between the 0 deg.and 180 deg.gantry angles, the position and stability of couch rotational axis, the sag between the 90 deg.and 270 deg.gantry angles, the accuracy of cone placement on the collimator, the MLC offsets from the collimator rotational axis, and the position of laser lines relative to the radiation isocenter. The estimated accuracy of the method is ±0.2 mm. The observed reproducibility of the method is about ±0.1 mm. The total irradiation/illumination time is about 10 min per image. Data analysis, including the phosphor plate scanning, takes less than 5 min for each image. The method characterizes the radiation isocenter geometry with the high accuracy required for the stereotactic radiosurgery. In this respect, it is similar to the standard ball test for stereotactic machines. However, due to the usage of the MLC instead of the cross-hair/ball, it does not depend on the cross-hair/ball placement errors with respect to the lasers and it provides more information on the mechanical integrity of the linac/couch/laser system. Alternatively, it can be used as a highly accurate QA procedure for the nonstereotactic machines. Noteworthy is its

Independent dosimetric calculation with inclusion of head scatter and MLC transmission for IMRT

International Nuclear Information System (INIS)

Yang, Y.; Xing, L.; Li, J.G.; Palta, J.; Chen, Y.; Luxton, Gary; Boyer, A.

2003-01-01

Independent verification of the MU settings and dose calculation of IMRT treatment plans is an important step in the IMRT quality assurance (QA) procedure. At present, the verification is mainly based on experimental measurements, which are time consuming and labor intensive. Although a few simplified algorithms have recently been proposed for the independent dose (or MU) calculation, head scatter has not been precisely taken into account in all these investigations and the dose validation has mainly been limited to the central axis. In this work we developed an effective computer algorithm for IMRT MU and dose validation. The technique is superior to the currently available computer-based MU check systems in that (1) it takes full consideration of the head scatter and leaf transmission effects; and (2) it allows a precise dose calculation at an arbitrary spatial point instead of merely a point on the central axis. In the algorithm the dose at an arbitrary spatial point is expressed as a summation of the contributions of primary and scatter radiation from all beamlets. Each beamlet is modulated by a dynamic modulation factor (DMF), which is determined by the MLC leaf trajectories, the head scatter, the jaw positions, and the MLC leaf transmission. A three-source model was used to calculate the head scatter distribution for irregular segments shaped by MLC and the scatter dose contributions were computed using a modified Clarkson method. The system reads in MLC leaf sequence files (or RTP files) generated by the Corvus (NOMOS Corporation, Sewickley, PA) inverse planning system and then computes the doses at the desired points. The algorithm was applied to study the dose distributions of several testing intensity modulated fields and two multifield Corvus plans and the results were compared with Corvus plans and experimental measurements. The final dose calculations at most spatial points agreed with the experimental measurements to within 3% for both the specially

Potential of discrete Gaussian edge feathering method for improving abutment dosimetry in eMLC-delivered segmented-field electron conformal therapy

Energy Technology Data Exchange (ETDEWEB)

Eley, John G.; Hogstrom, Kenneth R.; Matthews, Kenneth L.; Parker, Brent C.; Price, Michael J. [Department of Physics and Astronomy, Louisiana State University and Agricultural and Mechanical College, 202 Nicholson Hall, Tower Drive, Baton Rouge, Louisiana 70803-4001 (United States); Department of Physics and Astronomy, Louisiana State University and Agricultural and Mechanical College, 202 Nicholson Hall, Tower Drive, Baton Rouge, Louisiana 70803-4001 (United States) and Mary Bird Perkins Cancer Center, 4950 Essen Lane, Baton Rouge, Louisiana 70809-3482 (United States); Department of Physics and Astronomy, Louisiana State University and Agricultural and Mechanical College, 202 Nicholson Hall, Tower Drive, Baton Rouge, Louisiana 70803-4001 (United States); Department of Physics and Astronomy, Louisiana State University and Agricultural and Mechanical College, 202 Nicholson Hall, Tower Drive, Baton Rouge, Louisiana 70803-4001 (United States) and Mary Bird Perkins Cancer Center, 4950 Essen Lane, Baton Rouge, Louisiana 70809-3482 (United States)

2011-12-15

Purpose: The purpose of this work was to investigate the potential of discrete Gaussian edge feathering of the higher energy electron fields for improving abutment dosimetry in the planning volume when using an electron multileaf collimator (eMLC) to deliver segmented-field electron conformal therapy (ECT). Methods: A discrete (five-step) Gaussian edge spread function was used to match dose penumbras of differing beam energies (6-20 MeV) at a specified depth in a water phantom. Software was developed to define the leaf eMLC positions of an eMLC that most closely fit each electron field shape. The effect of 1D edge feathering of the higher energy field on dose homogeneity was computed and measured for segmented-field ECT treatment plans for three 2D PTVs in a water phantom, i.e., depth from the water surface to the distal PTV surface varied as a function of the x-axis (parallel to leaf motion) and remained constant along the y-axis (perpendicular to leaf motion). Additionally, the effect of 2D edge feathering was computed and measured for one radially symmetric, 3D PTV in a water phantom, i.e., depth from the water surface to the distal PTV surface varied as a function of both axes. For the 3D PTV, the feathering scheme was evaluated for 0.1-1.0-cm leaf widths. Dose calculations were performed using the pencil beam dose algorithm in the Pinnacle{sup 3} treatment planning system. Dose verification measurements were made using a prototype eMLC (1-cm leaf width). Results: 1D discrete Gaussian edge feathering reduced the standard deviation of dose in the 2D PTVs by 34, 34, and 39%. In the 3D PTV, the broad leaf width (1 cm) of the eMLC hindered the 2D application of the feathering solution to the 3D PTV, and the standard deviation of dose increased by 10%. However, 2D discrete Gaussian edge feathering with simulated eMLC leaf widths of 0.1-0.5 cm reduced the standard deviation of dose in the 3D PTV by 33-28%, respectively. Conclusions: A five-step discrete Gaussian edge

[Study of 103 cases of odontogenic cysts].

Science.gov (United States)

Moctezuma-Bravo, Gustavo Sergio; Magallanes-González, Eduardo

2009-01-01

To describe characteristics of odontogenic cysts in a Mexican population. A retrospective study of 103 odontogenic cysts in 86 patients was done. The data were obtained from files of the Pathology Department of a General Hospital. We observed a frequency of the 8.13 % of odontogenic cysts (103) in 1266 pathological studies. The dentigerous cyst 56 % and odontogenic keratocyst 33 % were the most common odontogenic cysts. Sixty one percent of the cysts appeared in the second and third decades of life. In 71 cysts, 42 % appeared in the posterior region jaw, 29 % in the anterior region of the maxilla and 21 % in the posterior region of the maxilla. A 6.7 % developed a recurrence after treatment and a case of keratocyst of posterior region of the maxilla was associated with epidermoid carcinoma. The study included three women with the syndrome of carcinoma of the basal cell nevus, who presented multiple keratocysts. The dentigerous cysts and odontogenic keratocysts were the most frequent odontogenic cysts. They appeared mainly in the second and third decades of life.

Contrast-enhanced MRI of intrasellar arachnoid cysts: relationship between the pituitary gland and cyst

International Nuclear Information System (INIS)

Nomura, M.; Kanazawa Univ. School of Medicine; Tachibana, O.; Hasegawa, M.; Kohda, Y.; Nakada, M.; Yamashima, T.; Yamashita, J.; Suzuki, M.

1996-01-01

We recently encountered two large intrasellar arachnoid cysts extending to the suprasellar region. The intensity of the cyst contents was identical to that of the cerebrospinal fluid on both T1- and T2-weighted MRI. On contrast-enhanced MRI, the pituitary gland was compressed posteroinferiorly and flattened in the sella turcica. In this report of rare intrasellar arachnoid cysts the discussion is focused on dislocation of the pituitary gland. (orig.)

A Case of Generalized Auditory Agnosia with Unilateral Subcortical Brain Lesion

Science.gov (United States)

Suh, Hyee; Kim, Soo Yeon; Kim, Sook Hee; Chang, Jae Hyeok; Shin, Yong Beom; Ko, Hyun-Yoon

2012-01-01

The mechanisms and functional anatomy underlying the early stages of speech perception are still not well understood. Auditory agnosia is a deficit of auditory object processing defined as a disability to recognize spoken languages and/or nonverbal environmental sounds and music despite adequate hearing while spontaneous speech, reading and writing are preserved. Usually, either the bilateral or unilateral temporal lobe, especially the transverse gyral lesions, are responsible for auditory agnosia. Subcortical lesions without cortical damage rarely causes auditory agnosia. We present a 73-year-old right-handed male with generalized auditory agnosia caused by a unilateral subcortical lesion. He was not able to repeat or dictate but to perform fluent and comprehensible speech. He could understand and read written words and phrases. His auditory brainstem evoked potential and audiometry were intact. This case suggested that the subcortical lesion involving unilateral acoustic radiation could cause generalized auditory agnosia. PMID:23342322

An Allometric Analysis of Sex and Sex Chromosome Dosage Effects on Subcortical Anatomy in Humans

Science.gov (United States)

Clasen, Liv; Giedd, Jay N.; Blumenthal, Jonathan; Lerch, Jason P.; Chakravarty, M. Mallar; Raznahan, Armin

2016-01-01

Structural neuroimaging of humans with typical and atypical sex-chromosome complements has established the marked influence of both Yand X-/Y-chromosome dosage on total brain volume (TBV) and identified potential cortical substrates for the psychiatric phenotypes associated with sex-chromosome aneuploidy (SCA). Here, in a cohort of 354 humans with varying karyotypes (XX, XY, XXX, XXY, XYY, XXYY, XXXXY), we investigate sex and SCA effects on subcortical size and shape; focusing on the striatum, pallidum and thalamus. We find large effect-size differences in the volume and shape of all three structures as a function of sex and SCA. We correct for TBV effects with a novel allometric method harnessing normative scaling rules for subcortical size and shape in humans, which we derive here for the first time. We show that all three subcortical volumes scale sublinearly with TBV among healthy humans, mirroring known relationships between subcortical volume and TBV among species. Traditional TBV correction methods assume linear scaling and can therefore invert or exaggerate sex and SCA effects on subcortical anatomy. Allometric analysis restricts sex-differences to: (1) greater pallidal volume (PV) in males, and (2) relative caudate head expansion and ventral striatum contraction in females. Allometric analysis of SCA reveals that supernumerary X- and Y-chromosomes both cause disproportionate reductions in PV, and coordinated deformations of striatopallidal shape. Our study provides a novel understanding of sex and sex-chromosome dosage effects on subcortical organization, using an allometric approach that can be generalized to other basic and clinical structural neuroimaging settings. SIGNIFICANCE STATEMENT Sex and sex-chromosome dosage (SCD) are known to modulate human brain size and cortical anatomy, but very little is known regarding their impact on subcortical structures that work with the cortex to subserve a range of behaviors in health and disease. Moreover

Diagnosis and treatment of cysts of the liver

International Nuclear Information System (INIS)

Al'perovich, B.I.; Mitasov, V.Ya.

1989-01-01

Is is shown that ultrasonography, computer tomography, laparoscopy provide for liver cyst detection. Parasitic cyst of Echinococcus and opisthhordeiasis nature are subject to surgical treatment. Selective procedures under echinococcosis include echinococcotomy and liver resection, and under opisthorchiasis - liver resection. Under nonparasitic liver cysts of minor size dynamic observation is advisable, under medium, hard and multiple complication cysts - sergical treatment is advisable. Selective procedures under non-complicated cysts include cyst resection with tamponage using omentum, and under complicated multiple cysts - liver resection

CT findings of thyroglossal duct cyst

International Nuclear Information System (INIS)

Kim, Dong Oh; Kim, Hong Soo; So, Hyun Soon; Nam, Mee Young; Choi, Jae Ho; Rhee, Hak Song

1995-01-01

The purpose of this study was to evaluate the CT findings of thyroglossal duct cysts. Sixteen patients with pathologically proved thyroglossal duct cysts were included in the study. CT scans were assessed retrospectively for shape, size, location, density of the central portions, septations, rim enhancement, changes in the adjacent fascial planes and investment within the strap muscles in the infrahyoid cysts. Thirteen cases of thyroglossal duct cysts were seen as round or oval cystic masses, two cases of them were seen as irregular-shaped lobulated cystic masses, and one case was seen as ovoid soft tissue mass. The cysts were from 1.4 to 5.7 cm in diameter (mean, 2.6 cm). The cyst was infrahyoid in 15 cases and suprahyoid in one case. The cyst was located in midline in eight cases, off midline in four cases, and both midline and off midline in four cases. The density of the central portions ranged from 15 to 82HU (mean, 32HU). Septations were noted in four cases. Rim enhancement was seen in 14 cases (93%), and heterogeneously enhancing soft tissue mass was seen in one case. In four cases, abnormal fascial planes were observed. All but one of the infrahyoid cysts (14/15) were embedded within the strap muscles, and one case of them was located anteriorly to strap muscles. CT permits one to make the diagnosis a thyroglossal duct cyst with a high degree of accuracy, as it can differentiate thyroglossal duct cysts from the other anterior neck masses by their typical location, characteristic morphology, and investment within the strap muscles

P53 Protein Expression in Dental Follicle, Dentigerous Cyst, Odontogenic Keratocyst, and Inflammatory Subtypes of Cysts: An Immunohistochemical Study.

Science.gov (United States)

Fatemeh, Mashhadiabbas; Sepideh, Arab; Sara, Bagheri Seyedeh; Nazanin, Mahdavi

2017-05-01

An odontogenic keratocyst (OKC) is a developmental odontogenic cyst with aggressive clinical behavior. This cyst shows a different growth mechanism from the more common dentigerous cyst and now has been renamed as a keratocystic odontogenic tumor (KCOT). Inflammation can assist tumor growth via different mechanisms including dysregulation of the p53 gene. This study aims to assess and compare the expression of tumor suppressor gene p53 in inflamed and non-inflamed types of OKC and dentigerous cyst. Immunohistochemical expression of p53 was assessed in 14 cases of dental follicle, 34 cases of OKC (including 18 inflamed OKCs), and 31 cases of dentigerous cyst (including 16 inflamed cysts). The mean percentage of p53 positive cells was 0.7% in dental follicles, 5.4% in non-inflamed OKCs, 17.3% in inflamed OKCs, 1.2% in non-inflamed dentigerous cysts, and 2.2% in inflamed dentigerous cysts. The differences between the groups were statistically significant ( p < 0.050) except for the difference between inflamed and non-inflamed dentigerous cysts, and between dental follicle and non-inflamed dentigerous cyst. The difference in p53 expression in OKC and dentigerous cyst can explain their different growth mechanism and clinical behavior. Inflammation is responsible for the change in behavior of neoplastic epithelium of OKC via p53 overexpression.

P53 Protein Expression in Dental Follicle, Dentigerous Cyst, Odontogenic Keratocyst, and Inflammatory Subtypes of Cysts: An Immunohistochemical Study

Directory of Open Access Journals (Sweden)

Mashhadiabbas Fatemeh

2017-05-01

Full Text Available Objectives: An odontogenic keratocyst (OKC is a developmental odontogenic cyst with aggressive clinical behavior. This cyst shows a different growth mechanism from the more common dentigerous cyst and now has been renamed as a keratocystic odontogenic tumor (KCOT. Inflammation can assist tumor growth via different mechanisms including dysregulation of the p53 gene. This study aims to assess and compare the expression of tumor suppressor gene p53 in inflamed and non-inflamed types of OKC and dentigerous cyst. Methods: Immunohistochemical expression of p53 was assessed in 14 cases of dental follicle, 34 cases of OKC (including 18 inflamed OKCs, and 31 cases of dentigerous cyst (including 16 inflamed cysts. Results: The mean percentage of p53 positive cells was 0.7% in dental follicles, 5.4% in non-inflamed OKCs, 17.3% in inflamed OKCs, 1.2% in non-inflamed dentigerous cysts, and 2.2% in inflamed dentigerous cysts. The differences between the groups were statistically significant (p < 0.050 except for the difference between inflamed and non-inflamed dentigerous cysts, and between dental follicle and non-inflamed dentigerous cyst. Conclusions: The difference in p53 expression in OKC and dentigerous cyst can explain their different growth mechanism and clinical behavior. Inflammation is responsible for the change in behavior of neoplastic epithelium of OKC via p53 overexpression.

Parathyroid cysts: the Latin-American experience.

Science.gov (United States)

Román-González, Alejandro; Aristizábal, Natalia; Aguilar, Carolina; Palacios, Karen; Pérez, Juan Camilo; Vélez-Hoyos, Alejandro; Duque, Carlos Simon; Sanabria, Alvaro

2016-12-01

Parathyroid cyst is an infrequent and unsuspected disease. There are more than 300 hundred cases reported in the world literature, a few of them are from Latin America. The experience of our centers and a review of the cases are presented. Case report of a series of patients with parathyroid cyst from our institutions according to the CARE guidelines (Case Reports). A search of Medline, Embase, BIREME ( Biblioteca Regional de Medicina ) LILACS ( Literatura Latinoamericana y del Caribe en Ciencias de la Salud ), Google Scholar and Scielo ( Scientific Electronic Library on Line ) databases and telephonic or email communications with other experts from Latin-America was performed . Six patients with parathyroid cyst were found in our centers in Colombia. Most of them were managed with aspiration of the cyst. Two of them required surgery. Only one case was functional. Twelve reports from Latin America were found for a total of 18 cases in our region adding ours. Parathyroid cysts are uncommonly reported in Latin America. Most of them are diagnosed postoperatively. Suspicion for parathyroid cyst should be raised when a crystal clear fluid is aspirated from a cyst. The confirmation of the diagnosis may be easily done if parathyroid hormone (PTH) level is measured in the cyst fluid.

Orthokeratinized odontogenic cyst: A rare presentation

Directory of Open Access Journals (Sweden)

Neha Bhasin

2014-01-01

Full Text Available Orthokeratinized Odontogenic Cyst (OOC is a developmental cyst of odontogenic origin and was initially defined as the uncommon orthokeratinized variant of the Odontogenic Keratocyst (OKC, until the World Health Organization′s (WHO′s classification in 2005, where it was separated from the Keratocystic Odontogenic Tumor (KCOT. It is a relatively uncommon developmental cyst comprising of only 0.4% of all odontogenic cysts. It is rather mystifying that its radiographic features are similar to the dentigerous cyst and histological characteristics are similar to the odontogenic keratocyst; and it has inconsistent cytokeratin expression profiles overlapping with both the dentigerous cyst and odontogenic keratocyst as well as with the epidermis. It has a predilection for the posterior mandibular region. This is a report of a rare case of OOC in an unusual maxillary anterior region, with emphasis on its biological characteristics.

Giant radicular cyst of the maxilla

Science.gov (United States)

Deshmukh, Jeevanand; Shrivastava, Ratika; Bharath, Kashetty Panchakshari; Mallikarjuna, Rachappa

2014-01-01

Radicular cysts are inflammatory odontogenic cysts of tooth bearing areas of the jaws. Most of these lesions involve the apex of offending tooth and appear as well-defined radiolucencies. Owing to its clinical characteristics similar to other more commonly occurring lesions in the oral cavity, differential diagnosis should include dentigerous cyst, ameloblastoma, odontogenic keratocyst, periapical cementoma and Pindborg tumour. The present case report documents a massive radicular cyst crossing the midline of the palate. Based on clinical, radiographical and histopathological findings, the present case was diagnosed as an infected radicular cyst. The clinical characteristics of this cyst could be considered as an interesting and unusual due to its giant nature. The lesion was surgically enucleated along with the extraction of the associated tooth; preservation of all other teeth and vital structures, without any postoperative complications and satisfactory healing, was achieved. PMID:24792022

Molecular aspects of cyst nematodes.

Science.gov (United States)

Lilley, Catherine J; Atkinson, Howard J; Urwin, Peter E

2005-11-01

SUMMARY Taxonomy: Superkingdom Eukaryota; kingdom Metazoa; phylum Nematoda; class Chromadorea; order Tylenchida; suborder Tylenchina; superfamily Tylenchoidea; family Heteroderidae; subfamily Heteroderinae; main genera Heterodera and Globodera. Cyst nematodes comprise approximately 100 known species in six genera. They are pathogens of temperate, subtropical and tropical plant species and the host range of many species is narrow. The most economically important species are within the Globodera and Heterodera genera. Globodera pallida and G. rostochiensis are important pathogens of potato crops. There are many economic species in the Heterodera genus, including Heterodera glycines (soybean cyst nematode), H. avenae (cereal cyst nematode) and H. schachtii (sugar beet cyst nematode), the last of which attacks a range of Chenopodiaceae and Cruciferae, including Arabidopsis thaliana. Disease symptoms: Field symptoms of severe cyst nematode infection are often stunting, wilting and chlorosis, but considerable yield loss can occur without obvious symptoms. The only unique indicator of cyst nematode infection is the presence of adult female nematodes attached to host roots after several weeks of parasitism. Disease control: This is usually achieved by using integrated pest management involving cultural practices such as crop rotation, resistant cultivars if available and chemical control when economically justified.

A Rapid Subcortical Amygdala Route for Faces Irrespective of Spatial Frequency and Emotion.

Science.gov (United States)

McFadyen, Jessica; Mermillod, Martial; Mattingley, Jason B; Halász, Veronika; Garrido, Marta I

2017-04-05

There is significant controversy over the existence and function of a direct subcortical visual pathway to the amygdala. It is thought that this pathway rapidly transmits low spatial frequency information to the amygdala independently of the cortex, and yet the directionality of this function has never been determined. We used magnetoencephalography to measure neural activity while human participants discriminated the gender of neutral and fearful faces filtered for low or high spatial frequencies. We applied dynamic causal modeling to demonstrate that the most likely underlying neural network consisted of a pulvinar-amygdala connection that was uninfluenced by spatial frequency or emotion, and a cortical-amygdala connection that conveyed high spatial frequencies. Crucially, data-driven neural simulations revealed a clear temporal advantage of the subcortical connection over the cortical connection in influencing amygdala activity. Thus, our findings support the existence of a rapid subcortical pathway that is nonselective in terms of the spatial frequency or emotional content of faces. We propose that that the "coarseness" of the subcortical route may be better reframed as "generalized." SIGNIFICANCE STATEMENT The human amygdala coordinates how we respond to biologically relevant stimuli, such as threat or reward. It has been postulated that the amygdala first receives visual input via a rapid subcortical route that conveys "coarse" information, namely, low spatial frequencies. For the first time, the present paper provides direction-specific evidence from computational modeling that the subcortical route plays a generalized role in visual processing by rapidly transmitting raw, unfiltered information directly to the amygdala. This calls into question a widely held assumption across human and animal research that fear responses are produced faster by low spatial frequencies. Our proposed mechanism suggests organisms quickly generate fear responses to a wide range

The dosimetric impact of inversely optimized arc radiotherapy plan modulation for real-time dynamic MLC tracking delivery

DEFF Research Database (Denmark)

Falk, Marianne; Larsson, Tobias; Keall, P.

2012-01-01

Purpose: Real-time dynamic multileaf collimator (MLC) tracking for management of intrafraction tumor motion can be challenging for highly modulated beams, as the leaves need to travel far to adjust for target motion perpendicular to the leaf travel direction. The plan modulation can be reduced......-to-peak displacement of 2 cm and a cycle time of 6 s. The delivery was adjusted to the target motion using MLC tracking, guided in real-time by an infrared optical system. The dosimetric results were evaluated using gamma index evaluation with static target measurements as reference. Results: The plan quality...

Mammary and femoral hydatid cysts.

Science.gov (United States)

Shamim, Muhammad

2010-08-01

Hydatid cyst disease most commonly affects liver and lungs, but it can affect all viscera and soft tissues of the body. Simultaneous mammary and femoral hydatid cysts, without any other visceral involvement, are extremely rare. This is a case report of 25-years-old female, presenting with lump in left breast mimicking fibroadenoma and lump in right thigh mimicking fibroma. Both turned out to be hydatid cysts.

MRI of symptomatic Rathke`s cleft cyst. MR intensity of cyst contents and clinical manifestations

Energy Technology Data Exchange (ETDEWEB)

Takeichi, Yasuhiro [Soseikai General Hospital, Kyoto (Japan); Nakasu, Yoko; Handa, Jyoji

1997-07-01

We have not known surgical indications for incidental Rathke`s cleft cysts, because of our lack of knowledge about their natural history. In this study, we investigated whether symptomatic Rathke`s cleft cysts have any characteristic features in magnetic resonance (MR) signal intensities, and analyzed their relation to clinical manifestations and to patterns of suprasellar expansion. MR signal intensities on T1-weighted (T1W) and T2-weighted (T2W) images were categorized into 3 types in 78 cases including our 9 cases; type I, low signal intensity on T1W images and hyperintensity on T2W images in 25 cases; type II, hyperintensity on both T1W and T2W images in 20; and type III, low intensity on T2W images, in other 33. Patients of type I signal intensities presented with significantly high percentage of large cysts compressing the third ventricle than patients with other types. The patients of type I signal intensities also frequently had visual disturbance. Patients in type II showed significantly less percentage of large cysts. Anterior pituitary dysfunction was observed more often in patients of type II and III than patients of type I. We conclude that Rathke`s cleft cysts with MR signal intensity like cerebrospinal fluid (CSF) are slowly growing, and are frequently diagnosed as large cysts associated with visual disturbance. The patients with other types of MR signal intensities may suffer pituitary dysfunction or other symptoms before the cysts compress the hypothalamic region. The assessment of MR signal intensities may contribute in predicting clinical progression in patients with Rathke`s cleft cysts. (author)

SU-G-BRB-10: New Generation of High Frame-Rate and High Spatial-Resolution EPID QA System for Full-Body MLC-Based Robotic Radiosurgery

International Nuclear Information System (INIS)

Han, B; Xing, L; Wang, L

2016-01-01

Purpose: To systematically investigate an ultra-high spatial-resolution amorphous silicon flat-panel electronic portal imaging device (EPID) for MLC-based full-body robotic radiosurgery geometric and dosimetric quality assurance (QA). Methods: The high frame-rate and ultra-high spatial resolution EPID is an outstanding detector for measuring profiles, MLC-shaped radiosurgery field aperture verification, and small field dosimetry. A Monte Carlo based technique with a robotic linac specific response and calibration is developed to convert a raw EPID-measured image of a radiosurgery field into water-based dose distribution. The technique is applied to measure output factors and profiles for 6MV MLC-defined radiosurgery fields with various sizes ranging from 7.6mm×7.7mm to 100mm×100.1mm and the results are compared with the radiosurgery diode scan measurements in water tank. The EPID measured field sizes and the penumbra regions are analyzed to evaluate the MLC positioning accuracy. Results: For all MLC fields, the EPID measured output factors of MLC-shaped fields are in good agreement with the diode measurements. The mean output difference between the EPID and diode measurement is 0.05±0.87%. The max difference is −1.33% for 7.6mm×7.7mm field. The MLC field size derived from the EPID measurements are in good agreement comparing to the diode scan result. For crossline field sizes, the mean difference is −0.17mm±0.14mm with a maximum of −0.35mm for the 30.8mm×30.8mm field. For inline field sizes, the mean difference is +0.08mm±0.18mm with a maximum of +0.45mm for the 100mm×100.1mm field. The high resolution EPID is able to measure the whole radiation field, without the need to align the detector center perfectly at field center as diode or ion chamber measurement. The setup time is greatly reduced so that the whole process is possible for machine and patient-specific QA. Conclusion: The high spatial-resolution EPID is proved to be an accurate and efficient

A new classification system for congenital laryngeal cysts.

Science.gov (United States)

Forte, Vito; Fuoco, Gabriel; James, Adrian

2004-06-01

A new classification system for congenital laryngeal cysts based on the extent of the cyst and on the embryologic tissue of origin is proposed. Retrospective chart review. The charts of 20 patients with either congenital or acquired laryngeal cysts that were treated surgically between 1987 and 2002 at the Hospital for Sick Children, Toronto were retrospectively reviewed. Clinical presentation, radiologic findings, surgical management, histopathology, and outcome were recorded. A new classification system is proposed to better appreciate the origin of these cysts and to guide in their successful surgical management. Fourteen of the supraglottic and subglottic simple mucous retention cysts posed no diagnostic or therapeutic challenge and were treated successfully by a single endoscopic excision or marsupialization. The remaining six patients with congenital cysts in the study were deemed more complex, and all required open surgical procedures for cure. On the basis of the analysis of the data of these patients, a new classification of congenital laryngeal cysts is proposed. Type I cysts are confined to the larynx, the cyst wall composed of endodermal elements only, and can be managed endoscopically. Type II cysts extend beyond the confines of the larynx and require an external approach. The Type II cysts are further subclassified histologically on the basis of the embryologic tissue of origin: IIa, composed of endoderm only and IIb, containing endodermal and mesodermal elements (epithelium and cartilage) in the wall of the cyst. A new classification system for congenital laryngeal cysts is proposed on the basis of the extent of the cyst and the embryologic tissue of origin. This classification can help guide the surgeon with initial management and help us better understand the origin of these cysts.

Shared rhythmic subcortical GABAergic input to the entorhinal cortex and presubiculum.

Science.gov (United States)

Viney, Tim James; Salib, Minas; Joshi, Abhilasha; Unal, Gunes; Berry, Naomi; Somogyi, Peter

2018-04-05

Rhythmic theta frequency (~5-12 Hz) oscillations coordinate neuronal synchrony and higher frequency oscillations across the cortex. Spatial navigation and context-dependent episodic memories are represented in several interconnected regions including the hippocampal and entorhinal cortices, but the cellular mechanisms for their dynamic coupling remain to be defined. Using monosynaptically-restricted retrograde viral tracing in mice, we identified a subcortical GABAergic input from the medial septum that terminated in the entorhinal cortex, with collaterals innervating the dorsal presubiculum. Extracellularly recording and labeling GABAergic entorhinal-projecting neurons in awake behaving mice show that these subcortical neurons, named orchid cells, fire in long rhythmic bursts during immobility and locomotion. Orchid cells discharge near the peak of hippocampal and entorhinal theta oscillations, couple to entorhinal gamma oscillations, and target subpopulations of extra-hippocampal GABAergic interneurons. Thus, orchid cells are a specialized source of rhythmic subcortical GABAergic modulation of 'upstream' and 'downstream' cortico-cortical circuits involved in mnemonic functions. © 2018, Viney et al.

Botryoid odontogenic cyst developing from lateral periodontal cyst: A rare case and review on pathogenesis

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Piyush Arora

2012-01-01

Full Text Available Botryoid odontogenic cyst (BOC is considered to be a polycystic variant of the lateral periodontal cyst (LPC as the specimen resembled a cluster of grapes. It is a non-inflammatory odontogenic cyst. The BOCs can be unicystic or multicystic. These cysts have potential to extend in the bone and become multilocular and they have a high recurrence rate. Till now, only 73 cases of BOC have been reported. The pathogenesis of BOC is still debatable. We review different pathogenesis proposed for BOC and discuss a rare case of BOC developing from lining of an abnormally large LPC which showed aggressive behaviour in terms of growth and size.

Intestinal Duplication Cyst Mimicking as Mesenteric Cyst with Asso- ciated Ileal Atresia Type III A

OpenAIRE

Surekha Arakeri; Anilkumar Sirasagi

2013-01-01

Intestinal duplication cysts (IDC) are uncom-mon congenital malformations that couldpresent diagnostic and therapeutic challenge.They may be often mistaken as mesentericcysts, omental cyst, cystic lymphangioma etc.However, IDC are differentiated from otherintra-abdominal cystic lesions by presence ofgastrointestinal mucosal lining and smoothmuscles in their wall. We report a case of IDCmimicking as mesenteric cyst associated withatresia of ileum in a neonate presented withacute surgical emerg...

Odontogenic Keratocyst Mimicking Paradental Cyst

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Andrea Enrico Borgonovo

2014-01-01

Full Text Available Objective. The aim of this paper is to present an uncommon clinical and radiographic aspect of odontogenic keratocyst (OKC mimicking paradental cyst. Methods. A 32-year-old female patient showed a well-delimited radiolucent lesion connected with the root of the left third molar with close anatomical relationship with the mandibular canal. The clinical, radiographic, and anamnestic features lead us to diagnose a paradental cyst that was treated by enucleation after extraction of the partially impacted tooth. Results. Histological analysis showed typical histological features of PKC such as the presence of a lining of stratified squamous epithelium with a well-defined basal layer of palisading columnar of cuboidal cells. Conclusion. Initial X-ray analysis and the position of the lesion related to the third mandibular tooth caused us to mistakenly diagnose a paradental cyst. We were only able to identify the cyst as an PKC rather than a paradental cyst after histological analysis.

Reinke Edema: Watch For Vocal Fold Cysts.

Science.gov (United States)

Tüzüner, Arzu; Demirci, Sule; Yavanoglu, Ahmet; Kurkcuoglu, Melih; Arslan, Necmi

2015-06-01

Reinke edema is one of the common cause of dysphonia middle-aged population, and severe thickening of vocal folds require surgical treatment. Smoking plays a major role on etiology. Vocal fold cysts are also benign lesions and vocal trauma blamed for acquired cysts. We would like to present 3 cases with vocal fold cyst related with Reinke edema. First case had a subepidermal epidermoid cyst with Reinke edema, which could be easily observed before surgery during laryngostroboscopy. Second case had a mucous retention cyst into the edematous Reinke tissue, which was detected during surgical intervention, and third case had a epidermoid cyst that occurred 2 months after before microlaryngeal operation regarding Reinke edema reduction. These 3 cases revealed that surgical management of Reinke edema needs a careful dissection and close follow-up after surgery for presence of vocal fold cysts.

Improving IMRT-plan quality with MLC leaf position refinement post plan optimization

International Nuclear Information System (INIS)

Niu Ying; Zhang Guowei; Berman, Barry L.; Parke, William C.; Yi Byongyong; Yu, Cedric X.

2012-01-01

Purpose: In intensity-modulated radiation therapy (IMRT) planning, reducing the pencil-beam size may lead to a significant improvement in dose conformity, but also increase the time needed for the dose calculation and plan optimization. The authors develop and evaluate a postoptimization refinement (POpR) method, which makes fine adjustments to the multileaf collimator (MLC) leaf positions after plan optimization, enhancing the spatial precision and improving the plan quality without a significant impact on the computational burden. Methods: The authors’ POpR method is implemented using a commercial treatment planning system based on direct aperture optimization. After an IMRT plan is optimized using pencil beams with regular pencil-beam step size, a greedy search is conducted by looping through all of the involved MLC leaves to see if moving the MLC leaf in or out by half of a pencil-beam step size will improve the objective function value. The half-sized pencil beams, which are used for updating dose distribution in the greedy search, are derived from the existing full-sized pencil beams without need for further pencil-beam dose calculations. A benchmark phantom case and a head-and-neck (HN) case are studied for testing the authors’ POpR method. Results: Using a benchmark phantom and a HN case, the authors have verified that their POpR method can be an efficient technique in the IMRT planning process. Effectiveness of POpR is confirmed by noting significant improvements in objective function values. Dosimetric benefits of POpR are comparable to those of using a finer pencil-beam size from the optimization start, but with far less computation and time. Conclusions: The POpR is a feasible and practical method to significantly improve IMRT-plan quality without compromising the planning efficiency.

Epidermoid cyst post dermofasciectomy.

LENUS (Irish Health Repository)

Henry, Francis P

2010-01-01

We report the finding of an unusual presentation of an epidermoid cyst 3 years following dermofasciectomy for Dupuytren\\'s disease. Epidermoid cysts remain a rare entity in the palmoplanter distribution but also a very unusual finding within the confines of a full thickness skin graft.

Surgical management of calcaneal unicameral bone cysts.

Science.gov (United States)

Glaser, D L; Dormans, J P; Stanton, R P; Davidson, R S

1999-03-01

Unicameral bone cysts are not seen commonly in the calcaneus. Little is known about the etiology and natural history of these lesions. Calcaneal cysts often are symptomatic, although some of these lesions are detected as incidental findings. Treatment has been advocated based on the fear of pathologic fracture and collapse. Several published series have been divided in their favor for either open treatment or injection management. These series are small, and the optimal treatment is still in question. The current study compared the efficacy of methylprednisolone acetate injection treatment with curettage and bone grafting in the treatment of unicameral bone cysts of the calcaneus. All patients treated for unicameral bone cysts of the calcaneus during the past 7 years at two institutions were reviewed. Eleven patients met inclusion criteria. All diagnoses were confirmed radiographically or histologically. Demographic information, presenting complaints, diagnostic imaging, treatment modalities, and outcome were analyzed. Long term radiographic and subjective followup was obtained. Eighteen surgical procedures were performed on 11 patients with 12 cysts. Nine injections performed on six patients failed to show healing of the cyst. Nine cysts treated with curettage and bone grafting showed cyst healing. At mean followup of 28 months (range, 12-77 months), all 11 patients had no symptoms; there were no recurrences of the cyst in the nine patients who underwent bone grafting and persistence of the cyst in the two patients who underwent injection therapy. This review reports one of the largest series of cysts in this location. The results indicate that steroid injection treatment, although useful in other locations, may not be the best option for the management of unicameral bone cysts in the calcaneus. Curettage and bone grafting yielded uniformly good results.

Tarlov cyst: Case report and review of literature

Directory of Open Access Journals (Sweden)

Prashad Bhagwat

2007-01-01

Full Text Available We describe a case of sacral perineural cyst presenting with complaints of low back pain with neurological claudication. The patient was treated by laminectomy and excision of the cyst. Tarlov cysts (sacral perineural cysts are nerve root cysts found most commonly in the sacral roots, arising between the covering layer of the perineurium and the endoneurium near the dorsal root ganglion. The incidence of Tarlov cysts is 5% and most of them are asymptomatic, usually detected as incidental findings on MRI. Symptomatic Tarlov cysts are extremely rare, commonly presenting as sacral or lumbar pain syndromes, sciatica or rarely as cauda equina syndrome. Tarlov cysts should be considered in the differential diagnosis of patients presenting with these complaints.

Lymphoepithelial cyst of the submandibular gland

Directory of Open Access Journals (Sweden)

A Saneem Ahamed

2014-01-01

Full Text Available Lymphoepithelial cysts are benign, slowly growing unilocular or multilocular lesions that appear in the head and neck. They are also called Branchial cyst. The head and neck sites are the salivary glands(more commonly parotid and rarely submandibular gland and the oral cavity (usually the floor of the mouth. there are various methods of investigation available today, of which Fine needle aspiration cytology (FNAC can be used to provide an immediate diagnosis of a lymphoepithelial cyst. The other investigations include, Ultrasonogram,and Computed tomography.It usually occurs due to the process of lymphocyte-induced cystic ductular dilatation and the confirmatory diagnosis is always made postoperatively by histopathological examination. The mainstay in the treatment of a lymphoepithelial cyst remains the surgical approach, which includes complete enucleation of the cyst along with total excision of the involved salivary gland. This is a report of a lymphoepithelial cyst involving the submandibular salivary gland and its management.

Subconjunctival epidermoid cysts in Gorlin-Goltz syndrome.

Science.gov (United States)

De Craene, S; Batteauw, A; Van Lint, M; Claerhout, I; Decock, C

2014-08-01

Epidermoid cysts are common benign cysts which occur particularly on the skin of the face, neck and upper trunk. Subconjunctival location of these cysts is very rare and, until today, only seen in patients with Gorlin-Goltz syndrome. Histopathological examination of these cysts show similarities with odontogenic keratocysts, a typical clinical manifestation of Gorlin-Goltz syndrome.

Breast cysts in adolescents - diagnostics, monitoring, treatment

Energy Technology Data Exchange (ETDEWEB)

Jakubowska, A; Brzewski, M [Department of Paediatric Radiology of the Medical University of Warsaw, Warsaw (Poland); Grajewska-Ferens, M [Department of Paediatrics and Endocrinology of the Medical University of Warsaw, Warsaw (Poland)

2011-07-01

Background: The aim of the paper was the US evaluation of hormonal disorders and treatment results in adolescent girls and boys with breast cysts. Material/Methods: In the years 2001 - 2009, US examination of the breast was performed in 427 children aged 10 - 18 years, with clinically suspected breast pathologies. The indications for US examination typically included pain, breast swelling and a palpable tumor. The US examination was performed using a 7 - 12 MHz linear transducer. Results: Breast cysts were found in 42 children: 36 adolescent girls and 6 boys with gynaecomastia. Infected cysts were found in 35 children. The cysts ranged in size from 5 mm to 30 mm. In 5 of the girls, large cysts were treated by an incision and drainage, and in all the children with infected cysts, antibiotic therapy was used. Hormonal disorders were found in 30 girls. A follow-up examination was performed, and the observation time varied from 1/12 to 2 years. The cysts disappeared completely in 30 children. Hormonal therapy was introduced in 5 girls. Conclusions: Breast cysts found in US examinations are indications for check-up examinations including endocrinological diagnostics and, if the cyst is persistent, possibly for hormonal treatment. (authors)

Intestinal Duplication Cyst Mimicking as Mesenteric Cyst with Asso- ciated Ileal Atresia Type III A

Directory of Open Access Journals (Sweden)

Surekha Arakeri

2013-07-01

Full Text Available Intestinal duplication cysts (IDC are uncom-mon congenital malformations that couldpresent diagnostic and therapeutic challenge.They may be often mistaken as mesentericcysts, omental cyst, cystic lymphangioma etc.However, IDC are differentiated from otherintra-abdominal cystic lesions by presence ofgastrointestinal mucosal lining and smoothmuscles in their wall. We report a case of IDCmimicking as mesenteric cyst associated withatresia of ileum in a neonate presented withacute surgical emergency.

Epidermoid Cyst of Mandible Ramus: Case Report.

Science.gov (United States)

Loxha, Mergime Prekazi; Salihu, Sami; Kryeziu, Kaltrina; Loxha, Sadushe; Agani, Zana; Hamiti, Vjosa; Rexhepi, Aida

2016-06-01

An epidermoid cyst is a benign cyst usually found on the skin. Bone cysts are very rare and if they appear in bone they usually appear in the distal phalanges of the fingers. Epidermoid cysts of the jaws are uncommon. We present a case, of a 41 year-old female patient admitted to our department because of pain and swelling in the parotid and masseteric region-left side. There was no trismus, pathological findings in skin, high body temperature level, infra-alveolar nerves anesthesia or lymphadenopathy present. The orthopantomography revealed a cystic lesion and a unilocular lesion that included mandibular ramus on the left side with 3 cm in diameter. Under total anesthesia, a cyst had been reached and was enucleated. Histopathologic findings showed that the pathologic lesion was an epidermoid cyst. Epidermoid and dermoid cysts are rare, benign lesions found throughout the body. Only a few cases in literature describe an intraossesus epidermoid cyst. Our case is an epidermoid cyst with a rare location in the region of the mandibular ramus. It is not associated with any trauma in this region except medical history reveals there was an operative removal of a wisdom tooth 12 years ago in the same side. These cysts are interesting from the etiological point of view. They should be considered in the differential diagnosis of other radiolucent lesions of the jaws. Surgically they have a very good prognosis, and are non-aggressive lesions.

Chronic hematic cyst of the temporomandibular joint

International Nuclear Information System (INIS)

Orhan, K.; Delilbasi, C.; Nishiyama, H.; Furukawa, S.; Mitsunobu, K.

2005-01-01

Hematic cyst refers to accumulation of blood or blood breakdown products in a non epithelium-lined fibrous tissue capsule. Hepatic cyst is a term often used for deeply placed, incompletely resorbed hematoma hemorrhagic cyst, which may remain unchanged and unidentified for long periods of time. Trauma is the major causative factor, although it is often vague or totally uncalled by the patient. Chronic hematic cysts are uncommon lesions those can present diagnostic challenge. In this article we report a first case of a chronic hematic cyst of the temporomandibular joint TMJ. (author)

Safety and Efficacy of MLC601 in Iranian Patients after Stroke: A Double-Blind, Placebo-Controlled Clinical Trial

Directory of Open Access Journals (Sweden)

A. A. Harandi

2011-01-01

Full Text Available Objective. To investigate the safety and efficacy of MLC601 (NeuroAid as a traditional Chinese medicine on motor recovery after ischemic stroke. Methods. This study was a double-blind, placebo-controlled clinical trial on 150 patients with a recent (less than 1 month ischemic stroke. All patients were given either MLC601 (100 patients or placebo (50 patients, 4 capsules 3 times a day, as an add-on to standard stroke treatment for 3 months. Results. Sex, age, elapsed time from stroke onset, and risk factors in the treatment group were not significantly different from placebo group at baseline (P>.05. Repeated measures analysis showed that Fugl-Meyer assessment was significantly higher in the treatment group during 12 weeks after stroke (P<.001. Good tolerability to treatment was shown, and adverse events were mild and transient. Conclusion. MLC601 showed better motor recovery than placebo and was safe on top of standard ischemic stroke medications especially in the severe and moderate cases.

Host Th1/Th2 immune response to Taenia solium cyst antigens in relation to cyst burden of neurocysticercosis.

Science.gov (United States)

Tharmalingam, J; Prabhakar, A T; Gangadaran, P; Dorny, P; Vercruysse, J; Geldhof, P; Rajshekhar, V; Alexander, M; Oommen, A

2016-10-01

Neurocysticercosis (NCC), Taenia solium larval infection of the brain, is an important cause of acquired seizures in endemic countries, which relate to number, location and degenerating cysts in the brain. Multicyst infections are common in endemic countries although single-cyst infection prevails in India. Single-cyst infections in an endemic country suggest a role for host immunity limiting the infection. This study examined ex vivo CD4(+) T cells and in vitro Th1 and Th2 cytokine responses to T. solium cyst antigens of peripheral blood mononuclear cells of healthy subjects from endemic and nonendemic regions and of single- and multicyst-infected patients for association with cyst burden of NCC. T. solium cyst antigens elicited a Th1 cytokine response in healthy subjects of T. solium-endemic and T. solium-non-endemic regions and those with single-cyst infections and a Th2 cytokine response from subjects with multicyst neurocysticercosis. Multicyst neurocysticercosis subjects also exhibited low levels of effector memory CD4(+) T cells. Th1 cytokine response of T. solium exposure and low infectious loads may aid in limiting cyst number. Th2 cytokines and low effector T cells may enable multiple-cyst infections to establish and persist. © 2016 John Wiley & Sons Ltd.

Prevalence of developmental odontogenic cysts in children and adolescents with emphasis on dentigerous cyst and odontogenic keratocyst (keratocystic odontogenic tumor).

Science.gov (United States)

Li, Nannan; Gao, Xing; Xu, Ziyuan; Chen, Zhuo; Zhu, Laikuan; Wang, Jinrui; Liu, Wei

2014-11-01

To investigate the incidence and prevalence of developmental odontogenic cysts in children and adolescents and compare the features of the two most common types, dentigerous cyst and keratocystic odontogenic tumor (KCOT). A retrospective review in a series of 369 patients with all histological diagnoses of developmental odontogenic cysts in children (≤12 years) and adolescents (13-18 years) was conducted. Among these, 361 (97.8%) patients were diagnosed as dentigerous cyst (n = 281) and KCOT (n = 80), with the male-to-female ratios of dentigerous cyst and KCOT both being 2:1. The average age of the patients with KCOT was older than that of those with dentigerous cyst (14.7 years vs 11.8 years, p < 0.001). Dentigerous cyst (59.1%) was more common in children, but KCOT (78.8%) was more common in adolescents (p < 0.001). Dentigerous cyst (57.6%) predominantly located on the maxilla, but KCOT (60.3%) predominantly located on the mandible (p = 0.010). Adolescent patients with lesions located on the mandible would favor KCOT over dentigerous cyst. This study aids in better knowledge of the prevalence of developmental odontogenic cysts in a large pediatric population, and shows that a well-supported early diagnosis is indispensable for a more adequate treatment.

Laparoscopic excision of a newborn rectal duplication cyst.

Science.gov (United States)

Hartin, Charles W; Lau, Stanley T; Escobar, Mauricio A; Glick, Philip L

2008-08-01

Congenital rectal duplication cyst is a rare entity treated with surgical excision. Without treatment, a rectal duplication cyst may cause a variety of complications, most notably, transforming into a malignancy. We report on a 7-week-old girl who was found to have a rectal duplication cyst. The rectal duplication cyst was successfully excised laparoscopically. Rectal duplication cysts are rare alimentary tract anomalies generally discovered during childhood. Complications include symptoms arising from the cyst and the possibility of malignant degeneration. They are typically managed by surgical excision.

Treatment planning for MLC based robotic radiosurgery for brain metastases: plan comparison with circular fields and suggestions for planning strategies

Directory of Open Access Journals (Sweden)

Schmitt Daniela

2017-09-01

Full Text Available To evaluate the possible range of application of the new InCise2 MLC for the CyberKnife M6 system in brain radiosurgery, a plan comparison was made for 10 brain metastases sized between 1.5 and 9cm3 in 10 patients treated in a single fraction each. The target volumes consist of a PTV derived by expanding the GTV by 1mm and were chosen to have diversity in the cohort regarding regularity of shape, location and the structures needed to be blocked for beam transmission in the vicinity. For each case, two treatment plans were optimized: one using the MLC and one using the IRIS-collimator providing variable circular fields. Plan re-quirements were: dose prescription to the 70% isodose line (18 or 20Gy, 100% GTV coverage, ≥98% PTV coverage, undisturbed central high dose region (95% of maximum dose and a conformity index as low as possible. Plan com-parison parameters were: conformity index (CI, high-dose gradient index (GIH, low-dose gradient index (GIL, total number of monitor units (MU and expected treatment time (TT. For all cases, clinically acceptable plans could be gen-erated with the following results (mean±SD for CI, GIH, GIL, MU and TT, respectively for the MLC plans: 1.09±0.03, 2.77±0.26, 2.61±0.08, 4514±830MU and 27±5min and for the IRIS plans: 1.05±0.01, 3.00±0.35, 2.46±0.08, 8557±1335MU and 42±7min. In summary, the MLC plans were on average less conformal and had a shallower dose gradient in the low dose region, but a steeper dose gradient in the high dose region. This is accompanied by a smaller vol-ume receiving 10Gy. A plan by plan comparison shows that usage of the MLC can spare about one half of the MUs and one third of treatment time. From these experiences and results suggestions for MLC planning strategy can be de-duced.

SU-F-T-629: Effect of Multi-Leaf Collimator (MLC) Width On Plan Quality of Single-Isocenter VMAT Intracranial Stereotactic Radiosurgery for Multiple Metastases

International Nuclear Information System (INIS)

Kraus, J; Thomas, E; Wu, X; Fiveash, J; Popple, R

2016-01-01

Purpose: Single-isocenter VMAT has been shown able to create high quality plans for complex intracranial multiple metastasis SRS cases. Linacs capable of the technique are typically outfitted with an MLC that consists of a combination of 5 mm and 10 mm leaves (standard) or 2.5 mm and 5 mm leaves (high-definition). In this study, we test the hypothesis that thinner collimator leaves are associated with improved plan quality. Methods: Ten multiple metastasis cases were identified and planned for VMAT SRS using a 10 MV flattening filter free beam. Plans were created for a standard (std) and a high-definition (HD) MLC. Published values for leaf transmission factor and dosimetric leaf gap were utilized. All other parameters were invariant. Conformity (plan and individual target), moderate isodose spill (V50%), and low isodose spill (mean brain dose) were selected for analysis. Results: Compared to standard MLC, HD-MLC improved overall plan conformity (median: Paddick CI-HD = 0.83, Paddick CI-std = 0.79; p = 0.004 and median: RTOG CI-HD =1.18, RTOG CI-std =1.24; p = 0.01 ), improved individual lesion conformity (median: Paddick CI-HD,i =0.77, Paddick CI-std,i =0.72; p < 0.001 and median: RTOG CI-HD,i = 1.28, RTOG CI-std,i =1.35; p < 0.001), improved moderate isodose spill (median: V50%-HD = 37.0 cc, V50%-std = 45.7 cc; p = 0.002), and improved low dose spill (median: dmean-HD = 2.90 Gy, dmean-std = 3.19 Gy; p = 0.002). Conclusion: For the single-isocenter VMAT SRS of multiple metastasis plans examined, use of HD-MLC modestly improved conformity, moderate isodose, and low isodose spill compared to standard MLC. However, in all cases we were able to generate clinically acceptable plans with the standard MLC. More work is need to further quantify the difference in cases with higher numbers of small targets and to better understand any potential clinical significance. This research was supported in part by Varian Medical Systems.

SU-F-T-629: Effect of Multi-Leaf Collimator (MLC) Width On Plan Quality of Single-Isocenter VMAT Intracranial Stereotactic Radiosurgery for Multiple Metastases

Energy Technology Data Exchange (ETDEWEB)

Kraus, J; Thomas, E; Wu, X; Fiveash, J; Popple, R [University Alabama Birmingham, Birmingham, AL (United States)

2016-06-15

Purpose: Single-isocenter VMAT has been shown able to create high quality plans for complex intracranial multiple metastasis SRS cases. Linacs capable of the technique are typically outfitted with an MLC that consists of a combination of 5 mm and 10 mm leaves (standard) or 2.5 mm and 5 mm leaves (high-definition). In this study, we test the hypothesis that thinner collimator leaves are associated with improved plan quality. Methods: Ten multiple metastasis cases were identified and planned for VMAT SRS using a 10 MV flattening filter free beam. Plans were created for a standard (std) and a high-definition (HD) MLC. Published values for leaf transmission factor and dosimetric leaf gap were utilized. All other parameters were invariant. Conformity (plan and individual target), moderate isodose spill (V50%), and low isodose spill (mean brain dose) were selected for analysis. Results: Compared to standard MLC, HD-MLC improved overall plan conformity (median: Paddick CI-HD = 0.83, Paddick CI-std = 0.79; p = 0.004 and median: RTOG CI-HD =1.18, RTOG CI-std =1.24; p = 0.01 ), improved individual lesion conformity (median: Paddick CI-HD,i =0.77, Paddick CI-std,i =0.72; p < 0.001 and median: RTOG CI-HD,i = 1.28, RTOG CI-std,i =1.35; p < 0.001), improved moderate isodose spill (median: V50%-HD = 37.0 cc, V50%-std = 45.7 cc; p = 0.002), and improved low dose spill (median: dmean-HD = 2.90 Gy, dmean-std = 3.19 Gy; p = 0.002). Conclusion: For the single-isocenter VMAT SRS of multiple metastasis plans examined, use of HD-MLC modestly improved conformity, moderate isodose, and low isodose spill compared to standard MLC. However, in all cases we were able to generate clinically acceptable plans with the standard MLC. More work is need to further quantify the difference in cases with higher numbers of small targets and to better understand any potential clinical significance. This research was supported in part by Varian Medical Systems.

Giant Epidermoid Cyst of the Thigh

Directory of Open Access Journals (Sweden)

NH Mohamed Haflah

2011-11-01

Full Text Available Epidermoid cyst is a common benign cutaneous swelling frequently encountered in surgical practice. It usually presents as a painless lump frequently occurring in hairbearing areas of the body particularly the scalp, scrotum, neck, shoulder and back. Giant epidermoid cysts commonly occur in hairy areas such as the scalp. We present here the case of a rare occurrence of a giant epidermoid cyst in the less hairy area of the right upper thigh mimicking a soft tissue sarcoma. Steps are highlighted for the management of this unusual cyst.

SEBACEOUS CYSTS MINOR SURGERY

Directory of Open Access Journals (Sweden)

I Gusti Ayu Agung Laksemi

2013-12-01

Full Text Available Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 Minor surgery is small surgery or localized example cut ulcers and boils, cyst excision, and suturing. Somethings that need to be considered in the preparation of the surgery is minor tools, operating rooms and operating tables, lighting, maintenance of tools and equipment, sterilization and desinfection equipment, preparation of patients and anesthesia. In general cysts is walled chamber that consist of fluid, cells and the remaining cells. Cysts are formed not due to inflammation although then be inflamed. Lining of the cysts wall is composed of fibrous tissue and usually coated epithelial cells or endothelial. Cysts formed by dilated glands and closed channels, glands, blood vessels, lymph channels or layers of the epidermis. Contents of the cysts wall consists of the results is serum, lymph, sweat sebum, epithelial cells, the stratum corneum, and hair. /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}

Minocycline hydrochloride sclerotherapy of renal cysts

Energy Technology Data Exchange (ETDEWEB)

Shin, Se Kweon; Kweon, Tae Beom; Seong, Hun; Jang, Kyung Jae; Chun, Byung Hee [Dae Dong General Hospital, Pusan (Korea, Republic of); Kim, Hack Jin [Pusan National University College of Medicine, pusan (Korea, Republic of)

1994-08-15

To report the effectiveness of Minocin sclerotherapy in the treatment of renal cysts. We performed minocin sclerotherapy to 19 patients with 21 renal cysts composed of 17 cases of solitary renal cyst and three cases of multiple renal cyst and one case of polycystic kidney confirmed by ultrasound and CT. After aspiration of cyst fluid, if the amount was less than 50 ml, 500 mg of minocin was mixed with 3 ml of normal saline, if more than 50 ml, 1000 mg of minocin mixed with 5 ml of normal saline were injected, and each case was followed-up over 3 months by ultrasound. Of all 21 renal cysts, 14 cases were followed-up three months after minocin sclerotherapy. In 12 of 14 case, the size of the cysts decreased by 10% or collapsed completely. Of the remaining two cases, one collapsed after 6 months while the other recurred after 6 months. Three cases were followed up after 20 months and only one of them recurred. 19 of all 21 cases(91%) were cured, and two of 21 cases(9%) were recurred. Pain was the only complaint and four of 10 cases needed analgesics. Sclerotherapy with minocin has low recurrence-rate and low complication, and relatively early high cure-rate.

Minocycline hydrochloride sclerotherapy of renal cysts

International Nuclear Information System (INIS)

Shin, Se Kweon; Kweon, Tae Beom; Seong, Hun; Jang, Kyung Jae; Chun, Byung Hee; Kim, Hack Jin

1994-01-01

To report the effectiveness of Minocin sclerotherapy in the treatment of renal cysts. We performed minocin sclerotherapy to 19 patients with 21 renal cysts composed of 17 cases of solitary renal cyst and three cases of multiple renal cyst and one case of polycystic kidney confirmed by ultrasound and CT. After aspiration of cyst fluid, if the amount was less than 50 ml, 500 mg of minocin was mixed with 3 ml of normal saline, if more than 50 ml, 1000 mg of minocin mixed with 5 ml of normal saline were injected, and each case was followed-up over 3 months by ultrasound. Of all 21 renal cysts, 14 cases were followed-up three months after minocin sclerotherapy. In 12 of 14 case, the size of the cysts decreased by 10% or collapsed completely. Of the remaining two cases, one collapsed after 6 months while the other recurred after 6 months. Three cases were followed up after 20 months and only one of them recurred. 19 of all 21 cases(91%) were cured, and two of 21 cases(9%) were recurred. Pain was the only complaint and four of 10 cases needed analgesics. Sclerotherapy with minocin has low recurrence-rate and low complication, and relatively early high cure-rate

Mucoepidermoid carcinoma in a salivary duct cyst of the parotid gland. Contribution to the development of tumours in salivary gland cysts.

Science.gov (United States)

Seifert, G

1996-12-01

Concerning the hypothesis that distinct types of salivary gland cysts may be the starting point of a salivary gland tumour, a histological examination of 1,661 salivary gland cysts was performed in order to analyse the cell types and their proliferative activity. Epithelial alterations were found especially in salivary duct cysts of parotid gland and in mucous retention cysts of minor salivary glands. Characteristic cellular changes were epithelial metaplasias (goblet cells, clear cells, squamous cells) and focal epithelial proliferations with plump or papillary plaques projecting into the cyst lumen. Only in one case had a mucoepidermoid carcinoma developed in the wall of a parotid duct cyst. The epithelial metaplasia and focal proliferative activity in salivary duct cysts is comparable to similar alterations in odontogenic cysts as possible early manifestation of a tumour, especially of an ameloblastoma or mucoepidermoid carcinoma. The differential diagnosis of salivary duct cysts must take primarily cystadenomas and cystic mucoepidermoid carcinomas of well-differentiated type into account.

Common genetic variants influence human subcortical brain structures

NARCIS (Netherlands)

Hibar, D.P.; Stein, J.L.; Renteria, M.E.; Arias-Vasquez, A.; Desrivières, S.; Jahanshad, N.; Toro, R.; Wittfeld, K.; Abramovic, L.; Andersson, M.; Aribisala, B.S.; Armstrong, N.J.; Bernard, M.; Bohlken, M.M.; Biks, M.P.; Bralten, J.; Brown, A.A.; Chakravarty, M.M.; Chen, Q.; Ching, C.R.K.; Cuellar-Partida, G.; den Braber, A.; Giddaluru, S.; Goldman, A.L.; Grimm, O.; Guadalupe, T.; Hass, J.; Woldehawariat, G.; Holmes, A.J.; Hoogman, M.; Janowitz, D.; Jia, T.; Kim, S.; Klein, M.; Kraemer, B.; Lee, P.H.; Olde Loohuis, L.M.; Luciano, M.; Macare, C.; Mather, K.A.; Mattheisen, M.; Milaneschi, Y.; Nho, K.; Papmeyer, M.; Ramasamy, A.; Risacher, S.L.; Roiz-Santiañez, R.; Rose, E.J.; Salami, A.; Sämann, P.G.; Schmaal, L.; Schork, A.J.; Shin, J.; Strike, L.T.; Teumer, A.; Donkelaar, M.M.J.; van Eijk, K.R.; Walters, R.K.; Westlye, L.T.; Welan, C.D.; Winkler, A.M.; Zwiers, M.P.; Alhusaini, S.; Athanasiu, L.; Ehrlich, S.; Hakobjan, M.M.H.; Hartberg, C.B.; Haukvik, U.K.; Heister, A.J.G.A.M.; Hoehn, D.; Kasperaviciute, D.; Liewald, D.C.M.; Lopez, L.M.; Makkinje, R.R.; Matarin, M.; Naber, M.A.M.; Reese McKay, D.; Needham, M.; Nugent, A.C.; Pütz, B.; Royle, N.A.; Shen, L.; Sprooten, E.; Trabzuni, D.; van der Marel, S.S.L.; van Hulzen, K.J.E.; Walton, E.; Wolf, C.; Almasy, L.; Ames, D.; Arepalli, S.; Assareh, A.A.; Bastin, M.E.; Brodaty, H.; Bulayeva, K.B.; Carless, M.A.; Cichon, S.; Corvin, A.; Curran, J.E.; Czisch, M.; de Zubicaray, G.I.; Dillman, A.; Duggirala, R.; Dyer, T.D.; Erk, S.; Fedko, I.O.; Ferrucci, L.; Foroud, T.M.; Fox, P.T.; Fukunaga, M.; Gibbs, J.R.; Göring, H.H.H.; Green, R.C.; Guelfi, S.; Hansell, N.K.; Hartman, C.A.; Hegenscheid, K.; Heinz, A.; Hernandez, D.G.; Heslenfeld, D.J.; Hoekstra, P.J.; Holsboer, F.; Homuth, G.; Hottenga, J.J.; Ikeda, M.; Jack, C.R., Jr.; Jenkinson, M.; Johnson, R.; Kanai, R.; Keil, M.; Kent, J.W. Jr.; Kochunov, P.; Kwok, J.B.; Lawrie, S.M.; Liu, X.; Longo, D.L.; McMahon, K.L.; Meisenzahl, E.; Melle, I.; Mohnke, S.; Montgomery, G.W.; Mostert, J.C.; Mühleisen, T.W.; Nalls, M.A.; Nichols, T.E.; Nilsson, L.G.; Nöthen, M.M.; Ohi, K.; Olvera, R.L.; Perez-Iglesias, R.; Pike, G.B.; Potkin, S.G.; Reinvang, I.; Reppermund, S.; Rietschel, M.; Romanczuk-Seiferth, N.; Rosen, G.D.; Rujescu, D.; Schnell, K.; Schofield, P.R.; Smith, C.; Steen, V.M.; Sussmann, J.E.; Thalamuthu, A.; Toga, A.W.; Traynor, B.J.; Troncoso, J.; Turner, J.A.; Valdés Hernández, M.C.; van t Ent, D.; van der Brug, M.; van der Wee, N.J.A.; van Tol, M.J.; Veltman, D.J.; Wassink, T.H.; Westmann, E.; Zielke, R.H.; Zonderman, A.B.; Ashbrook, D.G.; Hager, R.; Lu, L.; McMahon, F.J.; Morris, D.W.; Williams, R.W.; Brunner, H.G.; Buckner, R.L.; Buitelaar, J.K.; Cahn, W.; Calhoun, V.D.; Cavalleri, G.L.; Crespo-Facorro, B.; Dale, A.M.; Davies, G.E.; Delanty, N.; Depondt, C.; Djurovic, S.; Drevets, W.C.; Espeseth, T.; Gollub, R.L.; Ho, B.C.; Hoffmann, W.; Hosten, N.; Kahn, R.S.; Le Hellard, S.; Meyer-Lindenberg, A.; Müller-Myhsok, B.; Nauck, M.; Nyberg, L.; Pandolfo, M.; Penninx, B.W.J.H.; Roffman, J.L.; Sisodiya, SM; Smoller, J.W.; van Bokhoven, H.; van Haren, N.E.M.; Völzke, H.; Walter, H.; Weiner, M.W.; Wen, W.; White, T.; Agartz, I.; Andreassen, O.A.; Blangero, J.; Boomsma, D.I.; Brouwer, R.M.; Cannon, D.M.; Cookson, M.R.; de Geus, E.J.C.; Deary, I.J.; Donohoe, G.; Fernandez, G.; Fisher, S.E.; Francks, C.; Glahn, D.C.; Grabe, H.J.; Gruber, O.; Hardy, J.; Hashimoto, R.; Hulshoff Pol, H.E.; Jönsson, E.G.; Kloszewska, I.; Lovestone, S.; Mattay, V.S.; Mecocci, P.; McDonald, C.; McIntosh, A.M.; Ophoff, R.A.; Paus, T.; Pausova, Z.; Ryten, M.; Sachdev, P.S.; Saykin, A.J.; Simmons, A.; Singleton, A.; Soininen, H.; Wardlaw, J.M.; Weale, M.E.; Weinberger, D.R.; Adams, H.H.H.; Launer, L.J.; Seiler, S.; Schmidt, R.; Chauhan, G.; Satizabal, C.L.; Becker, J.T.; Yanek, L.; van der Lee, S.J.; Ebling, M.; Fischl, B.; Longstreth, Jr. W.T.; Greve, D.; Schmidt, H.; Nyquist, P.; Vinke, L.N.; van Duijn, C.M.; Xue, L.; Mazoyer, B.; Bis, J.C.; Gudnason, V.; Seshadri, S.; Arfan Ikram, M.; Martin, N.G.; Wright, M.J.; Schumann, G.; Franke, B.; Thompson, P.M.; Medland, S.E.

2015-01-01

The highly complex structure of the human brain is strongly shaped by genetic influences. Subcortical brain regions form circuits with cortical areas to coordinate movement, learning, memory and motivation, and altered circuits can lead to abnormal behaviour and disease. To investigate how common

Common genetic variants influence human subcortical brain structures

NARCIS (Netherlands)

D.P. Hibar (Derrek); J.L. Stein; M.E. Rentería (Miguel); A. Arias-Vásquez (Alejandro); S. Desrivières (Sylvane); N. Jahanshad (Neda); R. Toro (Roberto); K. Wittfeld (Katharina); L. Abramovic (Lucija); M. Andersson (Micael); B. Aribisala (Benjamin); N.J. Armstrong (Nicola J.); M. Bernard (Manon); M.M. Bohlken (Marc M.); M.P.M. Boks (Marco); L.B.C. Bralten (Linda); A.A. Brown (Andrew); M.M. Chakravarty (M. Mallar); Q. Chen (Qiang); C.R.K. Ching (Christopher); G. Cuellar-Partida (Gabriel); A. den Braber (Anouk); S. Giddaluru (Sudheer); A.L. Goldman (Aaron L.); O. Grimm (Oliver); T. Guadalupe (Tulio); J. Hass (Johanna); G. Woldehawariat (Girma); A.J. Holmes (Avram); M. Hoogman (Martine); D. Janowitz (Deborah); T. Jia (Tianye); S. Kim (Shinseog); M. Klein (Marieke); B. Kraemer (Bernd); P.H. Lee (Phil H.); L.M. Olde Loohuis (Loes M.); M. Luciano (Michelle); C. MacAre (Christine); R. Mather; M. Mattheisen (Manuel); Y. Milaneschi (Yuri); K. Nho (Kwangsik); M. Papmeyer (Martina); A. Ramasamy (Adaikalavan); S.L. Risacher (Shannon); R. Roiz-Santiañez (Roberto); E.J. Rose (Emma); A. Salami (Alireza); P.G. Sämann (Philipp); L. Schmaal (Lianne); N.J. Schork (Nicholas); J. Shin (Jean); L.T. Strike (Lachlan); A. Teumer (Alexander); M.M.J. Van Donkelaar (Marjolein M. J.); K.R. van Eijk (Kristel); R.K. Walters (Raymond); L.T. Westlye (Lars); C.D. Whelan (Christopher); A.M. Winkler (Anderson); M.P. Zwiers (Marcel); S. Alhusaini (Saud); L. Athanasiu (Lavinia); S.M. Ehrlich (Stefan); M. Hakobjan (Marina); C.B. Hartberg (Cecilie B.); U.K. Haukvik (Unn); A.J.G.A.M. Heister (Angelien J. G. A. M.); D. Hoehn (David); D. Kasperaviciute (Dalia); D.C. Liewald (David C.); L.M. Lopez (Lorna); R.R.R. Makkinje (Remco R. R.); M. Matarin (Mar); M.A.M. Naber (Marlies A. M.); D. Reese McKay; M. Needham (Margaret); A.C. Nugent (Allison); B. Pütz (Benno); N.A. Royle (Natalie); L. Shen (Li); R. Sprooten (Roy); D. Trabzuni (Danyah); S.S.L. Van Der Marel (Saskia S. L.); K.J.E. Van Hulzen (Kimm J. E.); E. Walton (Esther); A. Björnsson (Asgeir); L. Almasy (Laura); D.J. Ames (David); S. Arepalli (Sampath); A.A. Assareh; M.E. Bastin (Mark); H. Brodaty (Henry); K. Bulayeva (Kazima); M.A. Carless (Melanie); S. Cichon (Sven); A. Corvin (Aiden); J.E. Curran (Joanne); M. Czisch (Michael); G.I. de Zubicaray (Greig); A. Dillman (Allissa); A. Duggirala (Aparna); M.D. Dyer (Matthew); S. Erk; I. Fedko (Iryna); L. Ferrucci (Luigi); T. Foroud (Tatiana); P.T. Fox (Peter); M. Fukunaga (Masaki); J. Raphael Gibbs; H.H.H. Göring (Harald H.); R.C. Green (Robert C.); S. Guelfi (Sebastian); N.K. Hansell (Narelle); C.A. Hartman (Catharina); K. Hegenscheid (Katrin); J. Heinz (Judith); D.G. Hernandez (Dena); D.J. Heslenfeld (Dirk); P.J. Hoekstra (Pieter); F. Holsboer; G. Homuth (Georg); J.J. Hottenga (Jouke Jan); M. Ikeda (Masashi); C.R. Jack Jr. (Clifford); S. Jenkinson (Sarah); R. Johnson (Robert); R. Kanai (Ryota); M. Keil (Maria); J.W. Kent (Jack W.); P. Kochunov (Peter); J.B. Kwok (John B.); S. Lawrie (Stephen); X. Liu (Xinmin); D.L. Longo (Dan L.); K.L. Mcmahon (Katie); E. Meisenzahl (Eva); I. Melle (Ingrid); S. Mohnke (Sebastian); G.W. Montgomery (Grant); J.C. Mostert (Jeanette C.); T.W. Mühleisen (Thomas); M.A. Nalls (Michael); T.E. Nichols (Thomas); L.G. Nilsson; M.M. Nöthen (Markus); K. Ohi (Kazutaka); R.L. Olvera (Rene); R. Perez-Iglesias (Rocio); G. Bruce Pike; S.G. Potkin (Steven); I. Reinvang (Ivar); S. Reppermund; M. Rietschel (Marcella); N. Seiferth (Nina); G.D. Rosen (Glenn D.); D. Rujescu (Dan); K. Schnell (Kerry); C.J. Schofield (Christopher); C. Smith (Colin); V.M. Steen (Vidar); J. Sussmann (Jessika); A. Thalamuthu (Anbupalam); A.W. Toga (Arthur W.); B. Traynor (Bryan); J.C. Troncoso (Juan); J. Turner (Jessica); M.C. Valdés Hernández (Maria); D. van 't Ent (Dennis); M.P. van der Brug (Marcel); N.J. van der Wee (Nic); M.J.D. van Tol (Marie-José); D.J. Veltman (Dick); A.M.J. Wassink (Annemarie); E. Westman (Eric); R.H. Zielke (Ronald H.); A.B. Zonderman (Alan B.); D.G. Ashbrook (David G.); R. Hager (Reinmar); L. Lu (Lu); F.J. Mcmahon (Francis J); D.W. Morris (Derek W); R.W. Williams (Robert W.); H.G. Brunner; M. Buckner; J.K. Buitelaar (Jan K.); W. Cahn (Wiepke); V.D. Calhoun Vince D. (V.); G. Cavalleri (Gianpiero); B. Crespo-Facorro (Benedicto); A.M. Dale (Anders); G.E. Davies (Gareth); N. Delanty; C. Depondt (Chantal); S. Djurovic (Srdjan); D.A. Drevets (Douglas); T. Espeseth (Thomas); R.L. Gollub (Randy); B.C. Ho (Beng ); W. Hoffmann (Wolfgang); N. Hosten (Norbert); R. Kahn (René); S. Le Hellard (Stephanie); A. Meyer-Lindenberg; B. Müller-Myhsok (B.); M. Nauck (Matthias); L. Nyberg (Lars); M. Pandolfo (Massimo); B.W.J.H. Penninx (Brenda); J.L. Roffman (Joshua); S.M. Sisodiya (Sanjay); J.W. Smoller; H. van Bokhoven (Hans); N.E.M. van Haren (Neeltje E.); H. Völzke (Henry); H.J. Walter (Henrik); M.W. Weiner (Michael); W. Wen (Wei); T.J.H. White (Tonya); I. Agartz (Ingrid); O.A. Andreassen (Ole); J. Blangero (John); D.I. Boomsma (Dorret); R.M. Brouwer (Rachel); D.M. Cannon (Dara); M.R. Cookson (Mark); E.J.C. de Geus (Eco); I.J. Deary (Ian J.); D.J. Donohoe (Dennis); G. Fernandez (Guillén); S.E. Fisher (Simon); C. Francks (Clyde); D.C. Glahn (David); H.J. Grabe (Hans Jörgen); O. Gruber (Oliver); J. Hardy (John); R. Hashimoto (Ryota); H.E. Hulshoff Pol (Hilleke); E.G. Jönsson (Erik); I. Kloszewska (Iwona); S. Lovestone (Simon); V.S. Mattay (Venkata S.); P. Mecocci (Patrizia); C. McDonald (Colm); A.M. McIntosh (Andrew); R.A. Ophoff (Roel); T. Paus (Tomas); Z. Pausova (Zdenka); M. Ryten (Mina); P.S. Sachdev (Perminder); A.J. Saykin (Andrew); A. Simmons (Andrew); A. Singleton (Andrew); H. Soininen (H.); J.M. Wardlaw (J.); M.E. Weale (Michael); D.R. Weinberger (Daniel); H.H.H. Adams (Hieab); L.J. Launer (Lenore); S. Seiler (Stephan); R. Schmidt (Reinhold); G. Chauhan (Ganesh); C.L. Satizabal (Claudia L.); J.T. Becker (James); L.R. Yanek (Lisa); S.J. van der Lee (Sven); M. Ebling (Maritza); B. Fischl (Bruce); W.T. Longstreth Jr; D. Greve (Douglas); R. Schmidt (Reinhold); P. Nyquist (Paul); L.N. Vinke (Louis N.); C.M. van Duijn (Cornelia); L. Xue (Luting); B. Mazoyer (Bernard); J.C. Bis (Joshua); V. Gudnason (Vilmundur); S. Seshadri (Sudha); M.A. Ikram (Arfan); N.G. Martin (Nicholas); M.J. Wright (Margaret); G. Schumann (Gunter); B. Franke (Barbara); P.M. Thompson (Paul); S.E. Medland (Sarah Elizabeth)

2015-01-01

textabstractThe highly complex structure of the human brain is strongly shaped by genetic influences. Subcortical brain regions form circuits with cortical areas to coordinate movement, learning, memory and motivation, and altered circuits can lead to abnormal behaviour and disease. To investigate

The use of intensity-modulated radiation therapy photon beams for improving the dose uniformity of electron beams shaped with MLC.

Science.gov (United States)

Mosalaei, Homeira; Karnas, Scott; Shah, Sheel; Van Doodewaard, Sharon; Foster, Tim; Chen, Jeff

2012-01-01

Electrons are ideal for treating shallow tumors and sparing adjacent normal tissue. Conventionally, electron beams are collimated by cut-outs that are time-consuming to make and difficult to adapt to tumor shape throughout the course of treatment. We propose that electron cut-outs can be replaced using photon multileaf collimator (MLC). Two major problems of this approach are that the scattering of electrons causes penumbra widening because of a large air gap, and available commercial treatment planning systems (TPSs) do not support MLC-collimated electron beams. In this study, these difficulties were overcome by (1) modeling electron beams collimated by photon MLC for a commercial TPS, and (2) developing a technique to reduce electron beam penumbra by adding low-energy intensity-modulated radiation therapy (IMRT) photons (4 MV). We used blocks to simulate MLC shielding in the TPS. Inverse planning was used to optimize boost photon beams. This technique was applied to a parotid and a central nervous system (CNS) clinical case. Combined photon and electron plans were compared with conventional plans and verified using ion chamber, film, and a 2D diode array. Our studies showed that the beam penumbra for mixed beams with 90 cm source to surface distance (SSD) is comparable with electron applicators and cut-outs at 100 cm SSD. Our mixed-beam technique yielded more uniform dose to the planning target volume and lower doses to various organs at risk for both parotid and CNS clinical cases. The plans were verified with measurements, with more than 95% points passing the gamma criteria of 5% in dose difference and 5 mm for distance to agreement. In conclusion, the study has demonstrated the feasibility and potential advantage of using photon MLC to collimate electron beams with boost photon IMRT fields. Copyright © 2012 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.

Use of an amorphous silicon EPID for measuring MLC calibration at varying gantry angle

International Nuclear Information System (INIS)

Clarke, M F; Budgell, G J

2008-01-01

Amorphous silicon electronic portal imaging devices (EPIDs) are used to perform routine quality control (QC) checks on the multileaf collimators (MLCs) at this centre. Presently, these checks are performed at gantry angle 0 0 and are considered to be valid for all other angles. Since therapeutic procedures regularly require the delivery of MLC-defined fields to the patient at a wide range of gantry angles, the accuracy of the QC checks at other gantry angles has been investigated. When the gantry is rotated to angles other than 0 0 it was found that the apparent pixel size measured using the EPID varies up to a maximum value of 0.0015 mm per pixel due to a sag in the EPID of up to 9.2 mm. A correction factor was determined using two independent methods at a range of gantry angles between 0 deg. and 360 deg. The EPID was used to measure field sizes (defined by both x-jaws and MLC) at a range of gantry angles and, after this correction had been applied, any residual gravitational sag was studied. It was found that, when fields are defined by the x-jaws and y-back-up jaws, no errors of greater than 0.5 mm were measured and that these errors were no worse when the MLC was used. It was therefore concluded that, provided the correction is applied, measurements of the field size are, in practical terms, unaffected by gantry angle. Experiments were also performed to study how the reproducibility of individual leaves is affected by gantry angle. Measurements of the relative position of each individual leaf (minor offsets) were performed at a range of gantry angles and repeated three times. The position reproducibility was defined by the RMS error in the position of each leaf and this was found to be 0.24 mm and 0.21 mm for the two leaf banks at a gantry angle of 0 0 . When measurements were performed at a range of gantry angles, these reproducibility values remained within 0.09 mm and 0.11 mm. It was therefore concluded that the calibration of the Elekta MLC is stable at

The MLC tongue-and-groove effect on IMRT dose distributions

Energy Technology Data Exchange (ETDEWEB)

Deng Jun [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305 (United States). E-mail: jun@reyes.stanford.edu; Pawlicki, Todd; Chen Yan; Li Jinsheng; Jiang, Steve B.; Ma, C.-M. [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305 (United States)

2001-04-01

We have investigated the tongue-and-groove effect on the IMRT dose distributions for a Varian MLC. We have compared the dose distributions calculated using the intensity maps with and without the tongue-and-groove effect. Our results showed that, for one intensity-modulated treatment field, the maximum tongue-and-groove effect could be up to 10% of the maximum dose in the dose distributions. For an IMRT treatment with multiple gantry angles ({>=} 5), the difference between the dose distributions with and without the tongue-and-groove effect was hardly visible, less than 1.6% for the two typical clinical cases studied. After considering the patient setup errors, the dose distributions were smoothed with reduced and insignificant differences between plans with and without the tongue-and-groove effect. Therefore, for a multiple-field IMRT plan ({>=} 5), the tongue-and-groove effect on the IMRT dose distributions will be generally clinically insignificant due to the smearing effect of individual fields. The tongue-and-groove effect on an IMRT plan with small number of fields (<5) will vary depending on the number of fields in a plan (coplanar or non-coplanar), the MLC leaf sequences and the patient setup uncertainty, and may be significant (>5% of maximum dose) in some cases, especially when the patient setup uncertainty is small ({<=} 2 mm). (author)

Isolated Hydatid Cyst of Ankle: A Case Report

Directory of Open Access Journals (Sweden)

Tuna Demirdal

2015-11-01

Full Text Available Hydatid cyst is a zoonotic infection usually caused by Echinococcus granulosus. Hydatid cysts are most often localized in the liver and lungs. Isolated cases of hydatid cyst in soft tissue is very rare. The incidance of isolated soft tissue hydatid cyst is 2.3% in endemic areas. Medical treatment is successful in 30-40% of cases. The first choice of treatment is surgery, especially in atypical localization of hydatid cyst. We aimed to present our patient with ankle hydatid cyst, a rare case in the literature.

Percutaneous aspiration of hydatid cysts

International Nuclear Information System (INIS)

Hernandez, G.; Serrano, R.

1996-01-01

A perspective study was carried out to assess the efficacy of a combination of percutaneous aspiration plus oral albendazole to assess its efficacy as an alternative to surgery in the treatment of hydatid cyst. We performed percutaneous aspiration followed by injection of 20% hypertonic saline solution into 16 hydatid cysts in 13 patients. All the patients received oral albendazole (400 mg/12 hours) starting 2 days before and lasting until there weeks after the procedure. There were no anaphylactic reactions during or after the procedure. Follow-up included monthly ultrasound over a period ranging between 10 and 36 months. Three cysts disappeared completely; in 10 cases, the cysts cavity was replaced by a complex ultrasonographic findings, with strong signals similar to those of a pseudotumor. In another case, the aspirate was sterile and its morphology remained unchanged. In two cases, infection of the cyst ensued, requiring surgical treatment. We consider that percutaneous aspiration in combination with albendazole may prove to be a good alternative to surgery for the management of hepatic hydatid disease. (Author) 15 refs

Clinically practical intensity modulation for complex head and neck lesions using multiple, static MLC fields

International Nuclear Information System (INIS)

Verhey, L.J.; Xia, P.; Akazawa, P.

1997-01-01

Purpose: A number of different beam delivery methods have been proposed for implementing intensity modulated radiotherapy (IMRT), including fixed gantry with multiple static MLC fields (MSMLC - often referred to as 'stop and shoot'), fixed gantry with dynamic MLC (DMLC), intensity modulated arc therapy (IMAT), Tomotherapy and Peacock MIMiC. Using two complex head and neck cases as examples, we have compared dose distributions achievable with 3-D conformal radiotherapy (3DCRT) to those which can be achieved using IMRT delivered with MSMLC, DMLC and Peacock MIMiC. The goal is to demonstrate the potential value of IMRT in the treatment of complex lesions in the head and neck and to determine whether MSMLC, the simplest of the proposed IMRT methods, can produce dose distributions which are competitive with dynamic IMRT methods and which can be implemented in clinically acceptable times. Materials and Methods: Two patients with nasopharyngeal carcinoma were selected from the archives of the Department of Radiation Oncology at the University of California, San Francisco (UCSF). These patients were previously planned and treated with CT-based 3-D treatment planning methods which are routinely used at UCSF, including non-axial beam directions and partial transmission blocks when indicated. The CT data tapes were then read into a test version of CORVUS, an inverse treatment planning program being developed by NOMOS Corporation, target volumes and critical normal structures were outlined on axial CT slices and dose goals and limits were defined for the targets and normal tissues of interest. Optimized dose plans were then obtained for each delivery method including MSMLC (4 or 5 hand-selected beams with 3 levels of intensity), DMLC (9 evenly spaced axial beams with 10 levels of intensity) and Peacock MIMiC (55 axial beams spanning 270 degrees with 10 levels of intensity). Dose-volume histograms (DVH's) for all IMRT plans were then compared with the 3DCRT plans. Treatment

SU-E-P-21: Impact of MLC Position Errors On Simultaneous Integrated Boost Intensity-Modulated Radiotherapy for Nasopharyngeal Carcinoma

Energy Technology Data Exchange (ETDEWEB)

Chengqiang, L; Yin, Y; Chen, L [Shandong Cancer Hospital and Institute, 440 Jiyan Road, Jinan, 250117 (China)

2015-06-15

Purpose: To investigate the impact of MLC position errors on simultaneous integrated boost intensity-modulated radiotherapy (SIB-IMRT) for patients with nasopharyngeal carcinoma. Methods: To compare the dosimetric differences between the simulated plans and the clinical plans, ten patients with locally advanced NPC treated with SIB-IMRT were enrolled in this study. All plans were calculated with an inverse planning system (Pinnacle3, Philips Medical System{sub )}. Random errors −2mm to 2mm{sub )},shift errors{sub (} 2mm,1mm and 0.5mm) and systematic extension/ contraction errors (±2mm, ±1mm and ±0.5mm) of the MLC leaf position were introduced respectively into the original plans to create the simulated plans. Dosimetry factors were compared between the original and the simulated plans. Results: The dosimetric impact of the random and system shift errors of MLC position was insignificant within 2mm, the maximum changes in D95% of PGTV,PTV1,PTV2 were-0.92±0.51%,1.00±0.24% and 0.62±0.17%, the maximum changes in the D0.1cc of spinal cord and brainstem were 1.90±2.80% and −1.78±1.42%, the maximum changes in the Dmean of parotids were1.36±1.23% and −2.25±2.04%.However,the impact of MLC extension or contraction errors was found significant. For 2mm leaf extension errors, the average changes in D95% of PGTV,PTV1,PTV2 were 4.31±0.67%,4.29±0.65% and 4.79±0.82%, the averaged value of the D0.1cc to spinal cord and brainstem were increased by 7.39±5.25% and 6.32±2.28%,the averaged value of the mean dose to left and right parotid were increased by 12.75±2.02%,13.39±2.17% respectively. Conclusion: The dosimetric effect was insignificant for random MLC leaf position errors up to 2mm. There was a high sensitivity to dose distribution for MLC extension or contraction errors.We should pay attention to the anatomic changes in target organs and anatomical structures during the course,individual radiotherapy was recommended to ensure adaptive doses.

Choledochal cyst - three case report

International Nuclear Information System (INIS)

Goncalves, E.G.; Assamy, W.T.; Abbud, E.A.

1991-01-01

Three cases of choledochal cyst and a brief review of the pertinent literature are presented. Considerations regarding etiopathogenesis, difficulties in diagnosis, and treatment for the different types of cysts are made. (author)

Branchial Cleft Cyst

OpenAIRE

Nahata, Vaishali

2016-01-01

Branchial cleft cyst, sinuses, and fistulae are among the most commonly encountered congenital anomalies in pediatric otolaryngic practice. They can present difficulty in diagnosis and surgical management. Here, I report a case of 14-year-old boy who presented with asymptomatic, congenital swelling located just below the jawline in the lateral part of the neck. The lesion was excised surgically. Histopathology showed the cyst lined by squamous as well as columnar ciliated epithelium, which wa...

Mapping Subcortical Brain Maturation during Adolescence: Evidence of Hemisphere-and Sex-Specific Longitudinal Changes

Science.gov (United States)

Dennison, Meg; Whittle, Sarah; Yücel, Murat; Vijayakumar, Nandita; Kline, Alexandria; Simmons, Julian; Allen, Nicholas B.

2013-01-01

Early to mid-adolescence is an important developmental period for subcortical brain maturation, but longitudinal studies of these neurodevelopmental changes are lacking. The present study acquired repeated magnetic resonance images from 60 adolescent subjects (28 female) at ages 12.5 and 16.5 years to map changes in subcortical structure volumes.…

Mesenteric cyst(s presenting as acute intestinal obstruction in children: Three cases and literature review

Directory of Open Access Journals (Sweden)

Deepa Makhija

2016-09-01

Conclusions: Presentation of mesenteric cyst as acute obstruction in paediatric age group is rare and preoperative diagnosis is difficult. The larger cysts are more likely to have an acute presentation.

Metastasis of aggressive amoeboid sarcoma cells is dependent on Rho/ROCK/MLC signaling

Czech Academy of Sciences Publication Activity Database

Kosla, Jan; Paňková, D.; Plachý, Jiří; Tolde, O.; Bicanova, K.; Dvořák, Michal; Rosel, D.; Brabek, J.

2013-01-01

Roč. 11, č. 1 (2013), s. 51 ISSN 1478-811X R&D Projects: GA MŠk(CZ) LC06061 Institutional support: RVO:68378050 Keywords : metastasis * sarcoma * rhoA * ROCK * MLC * amoeboid invasiveness * 3D environment * chicken model Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.672, year: 2013

Sclerotherapy for hydrocoele and epididymal cysts.

Science.gov (United States)

Nash, J R

1979-04-01

A prospective study was carried out on the efficacy of sclerotherapy for the treatment of hydrocoeles and epididymal cysts. Thirty-six hydrocoeles and 13 epididymal cysts were treated and followed up for between 1 and 2 years. Thirty-four hydrocoeles were cured, 1 failed to respond to treatment and 1 recurred after treatment. All 13 epididymal cysts were cured.

Epidermal Inclusion Cysts of The Breast

Directory of Open Access Journals (Sweden)

Amir R. Motabar

2009-02-01

Full Text Available Epidermal inclusion cysts are uncommon in the breast, but the consequences can besevere when these cysts occur in the breast parenchyma. Here,we report two suchcases. The patient in case 1 was an 37-year-old woman with a 3-cm palpable mass inthe right breast. Mammography revealed a round and smoothly outlined mass, whichindicated a benign tumor, and sonography showed an irregularly shaped and heterogeneoushypoechoic mass, fibroadenoma was suspected on the basis of clinical andimage findings, but excisional biopsy revealed an epidermal inclusion cyst. The patientin case 2 was a 50-year-old woman with a 2.5-cm lesion in the left breast. Mammographyrevealed a round, dense, smoothly outlined mass, and sonography showeda well-defined, central hyperechoic mass. . Breast cancer was suspected on the basisof the sonographic findings and the age of the patient, but the resected specimen revealedan epidermal inclusion cyst. Although epidermal inclusion cysts are benign,occasionally they may play a role in the origin of squamous carcinoma of the breast. .Mammographic and sonographic features of an epidermal cyst may mimic a malignantlesion. Malignant change appears to occur more frequently in epidermal inclusioncysts in the mammary gland, compared to common epidermal inclusion cysts,and this may be associated with origination of mammary epidermal inclusion cystsfrom squamous metaplasia of the mammary duct epithelium.Epidermmoid inclusion cyst of the breast is potentially serious, although such cystsare rare, and differentiation from a malignant or benign breast tumor is required. Excisionis probably the most appropriate treatment, and can eliminate the possible riskof malignant transformation.

Common genetic variants influence human subcortical brain structures

NARCIS (Netherlands)

Hibar, Derrek P.; Stein, Jason L.; Renteria, Miguel E.; Arias-Vasquez, Alejandro; Desrivieres, Sylvane; Jahanshad, Neda; Toro, Roberto; Wittfeld, Katharina; Abramovic, Lucija; Andersson, Micael; Aribisala, Benjamin S.; Armstrong, Nicola J.; Bernard, Manon; Bohlken, Marc M.; Boks, Marco P.; Bralten, Janita; Brown, Andrew A.; Chakravarty, M. Mallar; Chen, Qiang; Ching, Christopher R. K.; Cuellar-Partida, Gabriel; den Braber, Anouk; Giddaluru, Sudheer; Goldman, Aaron L.; Grimm, Oliver; Guadalupe, Tulio; Hass, Johanna; Woldehawariat, Girma; Holmes, Avram J.; Hoogman, Martine; Janowitz, Deborah; Jia, Tianye; Kim, Sungeun; Klein, Marieke; Kraemer, Bernd; Lee, Phil H.; Loohuis, Loes M. Olde; Luciano, Michelle; Macare, Christine; Mather, Karen A.; Mattheisen, Manuel; Milaneschi, Yuri; Nho, Kwangsik; Papmeyer, Martina; Ramasamy, Adaikalavan; Risacher, Shannon L.; Roiz-Santianez, Roberto; Rose, Emma J.; Salami, Alireza; Saemann, Philipp G.; Schmaal, Lianne; Schork, Andrew J.; Shin, Jean; Strike, Lachlan T.; Teumer, Alexander; van Donkelaar, Marjolein M. J.; van Eijk, Kristel R.; Walters, Raymond K.; Westlye, Lars T.; Whelan, Christopher D.; Winkler, Anderson M.; Zwiers, Marcel P.; Alhusaini, Saud; Athanasiu, Lavinia; Ehrlich, Stefan; Hakobjan, Marina M. H.; Hartberg, Cecilie B.; Haukvik, Unn K.; Heister, Angelien J. G. A. M.; Hoehn, David; Kasperaviciute, Dalia; Liewald, David C. M.; Lopez, Lorna M.; Makkinje, Remco R. R.; Matarin, Mar; Naber, Marlies A. M.; McKay, D. Reese; Needham, Margaret; Nugent, Allison C.; Puetz, Benno; Royle, Natalie A.; Shen, Li; Sprooten, Emma; Trabzuni, Daniah; van der Marel, Saskia S. L.; van Hulzen, Kimm J. E.; Walton, Esther; Wolf, Christiane; Almasy, Laura; Ames, David; Arepalli, Sampath; Assareh, Amelia A.; Bastin, Mark E.; Brodaty, Henry; Bulayeva, Kazima B.; Carless, Melanie A.; Cichon, Sven; Corvin, Aiden; Curran, Joanne E.; Czisch, Michael; de Zubicaray, Greig I.; Dillman, Allissa; Duggirala, Ravi; Dyer, Thomas D.; Erk, Susanne; Fedko, Iryna O.; Ferrucci, Luigi; Foroud, Tatiana M.; Fox, Peter T.; Fukunaga, Masaki; Gibbs, J. Raphael; Goering, Harald H. H.; Green, Robert C.; Guelfi, Sebastian; Hansell, Narelle K.; Hartman, Catharina A.; Hegenscheid, Katrin; Heinz, Andreas; Hernandez, Dena G.; Heslenfeld, Dirk J.; Hoekstra, Pieter J.; Holsboer, Florian; Homuth, Georg; Hottenga, Jouke-Jan; Ikeda, Masashi; Jack, Clifford R.; Jenkinson, Mark; Johnson, Robert; Kanai, Ryota; Keil, Maria; Kent, Jack W.; Kochunov, Peter; Kwok, John B.; Lawrie, Stephen M.; Liu, Xinmin; Longo, Dan L.; McMahon, Katie L.; Meisenzah, Eva; Melle, Ingrid; Mahnke, Sebastian; Montgomery, Grant W.; Mostert, Jeanette C.; Muehleisen, Thomas W.; Nalls, Michael A.; Nichols, Thomas E.; Nilsson, Lars G.; Noethen, Markus M.; Ohi, Kazutaka; Olvera, Rene L.; Perez-Iglesias, Rocio; Pike, G. Bruce; Potkin, Steven G.; Reinvang, Ivar; Reppermund, Simone; Rietschel, Marcella; Romanczuk-Seiferth, Nina; Rosen, Glenn D.; Rujescu, Dan; Schnell, Knut; Schofield, Peter R.; Smith, Colin; Steen, Vidar M.; Sussmann, Jessika E.; Thalamuthu, Anbupalam; Toga, Arthur W.; Traynor, Bryan J.; Troncoso, Juan; Turner, Jessica A.; Valdes Hernandez, Maria C.; van't Ent, Dennis; van der Brug, Marcel; van der Wee, Nic J. A.; van Tol, Marie-Jose; Veltman, Dick J.; Wassink, Thomas H.; Westman, Eric; Zielke, Ronald H.; Zonderman, Alan B.; Ashbrook, David G.; Hager, Reinmar; Lu, Lu; McMahon, Francis J.; Morris, Derek W.; Williams, Robert W.; Brunner, Han G.; Buckner, Randy L.; Buitelaar, Jan K.; Cahn, Wiepke; Calhoun, Vince D.; Cavalleri, Gianpiero L.; Crespo-Facorro, Benedicto; Dale, Anders M.; Davies, Gareth E.; Delanty, Norman; Depondt, Chantal; Djurovic, Srdjan; Drevets, Wayne C.; Espeseth, Thomas; Gollub, Randy L.; Ho, Beng-Choon; Hoffman, Wolfgang; Hosten, Norbert; Kahn, Rene S.; Le Hellard, Stephanie; Meyer-Lindenberg, Andreas; Mueller-Myhsok, Bertram; Nauck, Matthias; Nyberg, Lars; Pandolfo, Massimo; Penninx, Brenda W. J. H.; Roffman, Joshua L.; Sisodiya, Sanjay M.; Smoller, Jordan W.; van Bokhoven, Hans; van Haren, Neeltje E. M.; Voelzke, Henry; Walter, Henrik; Weiner, Michael W.; Wen, Wei; White, Tonya; Agartz, Ingrid; Andreassen, Ole A.; Blangero, John; Boomsma, Dorret I.; Brouwer, Rachel M.; Cannon, Dara M.; Cookson, Mark R.; de Geus, Eco J. C.; Deary, Ian J.; Donohoe, Gary; Fernandez, Guillen; Fisher, Simon E.; Francks, Clyde; Glahn, David C.; Grabe, Hans J.; Gruber, Oliver; Hardy, John; Hashimoto, Ryota; Pol, Hilleke E. Hulshoff; Joensson, Erik G.; Kloszewska, Iwona; Lovestone, Simon; Mattay, Venkata S.; Mecocci, Patrizia; McDonald, Colm; McIntosh, Andrew M.; Ophoff, Roel A.; Paus, Tomas; Pausova, Zdenka; Ryten, Mina; Sachdev, Perminder S.; Saykin, Andrew J.; Simmons, Andy; Singleton, Andrew; Soininen, Hilkka; Wardlaw, Joanna M.; Weale, Michael E.; Weinberger, Daniel R.; Adams, Hieab H. H.; Launer, Lenore J.; Seiler, Stephan; Schmidt, Reinhold; Chauhan, Ganesh; Satizabal, Claudia L.; Becker, James T.; Yanek, Lisa; van der Lee, Sven J.; Ebling, Maritza; Fischl, Bruce; Longstreth, W. T.; Greve, Douglas; Schmidt, Helena; Nyquist, Paul; Vinke, Louis N.; van Duijn, Cornelia M.; Xue, Luting; Mazoyer, Bernard; Bis, Joshua C.; Gudnason, Vilmundur; Seshadri, Sudha; Ikram, M. Arfan; Martin, Nicholas G.; Wright, Margaret J.; Schumann, Gunter; Franke, Barbara; Thompson, Paul M.; Medland, Sarah E.

2015-01-01

The highly complex structure of the human brain is strongly shaped by genetic influences(1). Subcortical brain regions form circuits with cortical areas to coordinate movement(2), learning, memory(3) and motivation(4), and altered circuits can lead to abnormal behaviour and disease(5). To

Subcortical aphasia and cerebral blood flow using SPECT

International Nuclear Information System (INIS)

Celsis, P.; Puel, M.; Demonet, J.P.; Bonafe, A.; Cardebat, D.; Viallard, G.; Pujol, T.; Marc-Vergnes, J.P.; Rascol, A.

1985-01-01

Possible cerebral blood flow (CBF) alteration in subcortical aphasia was investigated by single-photon emission tomography (SPECT). The results confirm the capsulo-striatal lesions and also point to the high rate of ipsilateral thalamic and cortical dysfunction. (author). 8 refs.; 1 fig.; 1 tab

Biliary tract duplication cyst with gastric heterotopia

Energy Technology Data Exchange (ETDEWEB)

Grumbach, K.; Baker, D.H.; Weigert, J.; Altman, R.P.

1988-05-01

Cystic duplications of the biliary tract are rare anomalies, easily mistaken for choledochal cysts. Surgical drainage is the preferred therapy for choledochal cyst, but cystic duplication necessitates surgical excision as duplications may contain heterotopic gastric mucosa leading to peptic ulceration of the biliary tract. We report a case of biliary tract duplication cyst containing heterotopic alimentary mucosa which had initially been diagnosed and surgically treated as a choledochal cyst.

Biliary tract duplication cyst with gastric heterotopia

International Nuclear Information System (INIS)

Grumbach, K.; Baker, D.H.; Weigert, J.; Altman, R.P.

1988-01-01

Cystic duplications of the biliary tract are rare anomalies, easily mistaken for choledochal cysts. Surgical drainage is the preferred therapy for choledochal cyst, but cystic duplication necessitates surgical excision as duplications may contain heterotopic gastric mucosa leading to peptic ulceration of the biliary tract. We report a case of biliary tract duplication cyst containing heterotopic alimentary mucosa which had initially been diagnosed and surgically treated as a choledochal cyst. (orig.)

Subcortical grey matter changes in untreated, early stage Parkinson's disease without dementia.

Science.gov (United States)

Lee, Hye Mi; Kwon, Kyum-Yil; Kim, Min-Jik; Jang, Ji-Wan; Suh, Sang-Il; Koh, Seong-Beom; Kim, Ji Hyun

2014-06-01

Previous MRI studies have investigated cortical or subcortical grey matter changes in patients with Parkinson's disease (PD), yielding inconsistent findings between the studies. We therefore sought to determine whether focal cortical or subcortical grey matter changes may be present from the early disease stage. We recruited 49 untreated, early stage PD patients without dementia and 53 control subjects. Voxel-based morphometry was used to evaluate cortical grey matter changes, and automated volumetry and shape analysis were used to assess volume changes and shape deformation of the subcortical grey matter structures, respectively. Voxel-based morphometry showed neither reductions nor increases in grey matter volume in patients compared to controls. Compared to controls, PD patients had significant reductions in adjusted volumes of putamen, nucleus accumbens, and hippocampus (corrected p grey matter and clinical variables representing disease duration and severity. Our results suggest that untreated, early stage PD without dementia is associated with volume reduction and shape deformation of subcortical grey matter, but not with cortical grey matter reduction. Our findings of structural changes in the posterolateral putamen and ventromedial putamen/nucleus accumbens could provide neuroanatomical basis for the involvement of motor and limbic striatum, further implicating motor and non-motor symptoms in PD, respectively. Early hippocampal involvement might be related to the risk for developing dementia in PD patients. Copyright © 2014 Elsevier Ltd. All rights reserved.

Proteomic analysis of the cyst stage of Entamoeba histolytica.

Directory of Open Access Journals (Sweden)

Ibne Karim M Ali

Full Text Available The category B agent of bioterrorism, Entamoeba histolytica has a two-stage life cycle: an infective cyst stage, and an invasive trophozoite stage. Due to our inability to effectively induce encystation in vitro, our knowledge about the cyst form remains limited. This also hampers our ability to develop cyst-specific diagnostic tools.Three main aims were (i to identify E. histolytica proteins in cyst samples, (ii to enrich our knowledge about the cyst stage, and (iii to identify candidate proteins to develop cyst-specific diagnostic tools.Cysts were purified from the stool of infected individuals using Percoll (gradient purification. A highly sensitive LC-MS/MS mass spectrometer (Orbitrap was used to identify cyst proteins.A total of 417 non-redundant E. histolytica proteins were identified including 195 proteins that were never detected in trophozoite-derived proteomes or expressed sequence tag (EST datasets, consistent with cyst specificity. Cyst-wall specific glycoproteins Jacob, Jessie and chitinase were positively identified. Antibodies produced against Jacob identified cysts in fecal specimens and have potential utility as a diagnostic reagent. Several protein kinases, small GTPase signaling molecules, DNA repair proteins, epigenetic regulators, and surface associated proteins were also identified. Proteins we identified are likely to be among the most abundant in excreted cysts, and therefore show promise as diagnostic targets.The proteome data generated here are a first for naturally-occurring E. histolytica cysts, and they provide important insights into the infectious cyst form. Additionally, numerous unique candidate proteins were identified which will aid the development of new diagnostic tools for identification of E. histolytica cysts.

Minimally invasive management of hepatic cysts: indications and complications.

Science.gov (United States)

Vardakostas, D; Damaskos, C; Garmpis, N; Antoniou, E A; Kontzoglou, K; Kouraklis, G; Dimitroulis, D

2018-03-01

Liver cysts are divided into congenital and acquired. Congenital cystic lesions include polycystic liver disease, simple cysts, duct related and ciliated hepatic foregut cysts. Acquired cystic lesions are divided into infectious and non-infectious. The infectious cysts are the hydatid cyst, the amoebic abscess, and the pyogenic abscess, whereas the non-infectious cysts are neoplastic cysts and false cysts. While modern medicine provides a lot of minimally invasive therapeutic modalities, there has emerged a pressing need for understanding the various types of liver cysts, the possible minimal therapeutic options along with their indications and complications. We aim is to clarify the role of minimally invasive techniques in the management of hepatic cysts. A literature review was performed using the MEDLINE database. The search terms were: liver cyst, minimally invasive, laparoscopic, percutaneous, drainage and fenestration. We reviewed 82 English language publications articles, published until October 2017. Minimally invasive management of liver LC is an emerging field including many therapeutic modalities ranging from the percutaneous aspiration of pyogenic abscesses to laparoscopic hepatectomy for hepatic cystadenomas. The most used techniques are percutaneous drainage, laparoscopic fenestration, and laparoscopic hepatectomy. The application of the various minimally invasive approaches, as well as their indication and complications, depend on the type of the cystic lesion, its size and its position in the liver. Percutaneous drainage is mostly used in simple cysts, hydatid cysts, pyogenic abscesses and bilomas. Laparoscopic fenestration is mostly used in simple cysts and polycystic liver disease. Finally, laparoscopic hepatectomy is mostly used in polycystic liver disease, hydatid cysts, and cystadenomas.

Odontogenic cysts: analysis of 680 cases in Brazil.

Science.gov (United States)

Prockt, Anderson P; Schebela, Clarissa R; Maito, Fábio D M; Sant'Ana-Filho, Manoel; Rados, Pantelis V

2008-09-01

The purpose of this study was to evaluate the prevalence of 680 odontogenic cysts diagnosed in Porto Alegre, RS, Brazil, and to compare results with findings in the literature. Data of odontogenic cysts diagnosed from 1985 to 2005 were collected from the files of the Oral Pathology Laboratory of Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brazil, and entered in a standardized form for later comparisons. The most prevalent odontogenic cysts were radicular (72.50%), dentigerous (22.20%) and residual (4.26%) cysts. The mandible of white patients was the anatomic site and ethnic group most frequently affected by this disease. Four of the six types of cysts were more frequent in the second and fourth decades of life, and no significant differences were found between sexes in the diagnosis of odontogenic cysts. In conclusion, the prevalence of odontogenic cysts was similar to that reported in the literature, which shows that inflammatory cysts are the most frequent.

Intrathoracic Paraspinal Mesothelial Cyst: A Report of Two Cases

International Nuclear Information System (INIS)

Oh, Se Won; Choi, Yo Won; Jeon, Seok Chol; Heo, Jeong Nam; Park, Choong Ki; Paik, Seung Sam; Chung, Won Sang; Chon, Soon Ho

2010-01-01

Intrathoracic mesothelial cysts are congenital developmental cysts usually located in the anterior cardiophrenic angle region (so called, pericardial cysts). We report two rare cases of an intrathoracic paraspinal mesothelial cyst which was purely cystic and had no perceptible cyst wall on CT or MRI with histopathologic findings

Spinal meningeal cyst: analysis with low-field MRI

International Nuclear Information System (INIS)

Wu Hongzhou; Chen Yejia; Chen Ronghua; Chen Yanping

2010-01-01

Objective: To analyze the characteristics of spinal meningeal cyst in low-field MRI and to discuss its classification, subtype, clinical presentation, and differential diagnosis. Methods: Forty-two patients (20 male, 22 female) were examined with sagittal T 1 -and T 2 -, axial T 2 -weighted MR imaging. Twelve patients were also examined with contrast-enhanced MRI. Results: The cysts were classified using Nakors' classification as type Ia extradural meningeal cysts (4 patients), type Ib sacral meningeal cysts (32), type II extradural meningeal cysts with spinal nerve root fibers (4), and type III spinal intradural meningeal cysts (2). All 42 spinal meningeal cysts had well-defined boundaries with low T 1 and high T 2 signal intensities similar to cerebral spinal fluid. In type Ia, the lesions were often on the dorsum of mid-lower thoracic spinal cord compressing the spinal cord and displacing the extradural fat. In type Ib, the lesions were in the sacral canal with fat plane between the cyst and dural sac. In type II, the lesions contained nerve roots and were lateral to the dural sac. In type III, the lesions were often on the dorsum of spinal cord compressing and displacing the spinal cord anteriorly. Conclusion: Low-field MRI can clearly display the spinal meningeal cyst. Types Ia and Ib spinal meningeal cysts had typical features and can be easily diagnosed. Types II and III should be differentiated from cystic schwannomas and enterogenous cysts, respectively. (authors)

Branchial cleft cyst encircling the hypoglossal nerve

Science.gov (United States)

Long, Kristin L.; Spears, Carol; Kenady, Daniel E.

2013-01-01

Branchial cleft anomalies are a common cause of lateral neck masses and may present with infection, cyst enlargement or fistulas. They may affect any of the nearby neck structures, causing compressive symptoms or vessel thrombosis. We present a case of a branchial cleft cyst in a 10-year-old boy who had been present for 1year. At the time of operation, the cyst was found to completely envelop the hypoglossal nerve. While reports of hypoglossal nerve palsies due to external compression from cysts are known, we believe this to be the first report of direct nerve involvement by a branchial cleft cyst. PMID:24963902

MR findings in thyroglossal duct cysts

International Nuclear Information System (INIS)

Blandino, A.; Salvi, L.; Chirico, G.; Scribano, E.; Longo, M.; Pandolfo, I.

1990-01-01

Two patients with thyroglossal duct cysts have been studied with CT and MR. The typical CT feature of these cystic upper-neck lesions are depicted in literature, conversely MR findings are not well known. The homogeneous high intensity on T1-weighted images, higher than simple cyst or fluid, is the most typical feature of the thyroglossal cyst. (author). 12 refs.; 5 figs

Primary hydatid cysts of the pancreas

African Journals Online (AJOL)

Kurt

Hydatid cysts of the pancreas are rare. The reported incidence varies from 0.1% to 2% of patients with hydatid disease.4-7. Management may be diffi- cult as a hydatid cyst in the head of the pancreas may closely simulate a cystic tumour. In this study we report 4 cases of primary hydatid cysts involving the head of the ...

CT guided percutaneous renal cysts puncture with ethanol therapy

International Nuclear Information System (INIS)

Zhang Xuezhe; Lu Yan; Wang Wu; Huang Zhengguo; Ren An

2002-01-01

Objective: To analyse our clinical experience with CT guided percutaneous renal cysts puncture and ethanol therapy. Methods: Five hundred and ten renal cysts in 445 patients were undergone CT guided percutaneous renal cysts puncture and ethanol therapy. Among the 445 cases, 385 cases had solitary renal cyst, 53 multiple renal cysts, and 7 polycystic kidneys. The renal cysts varied in size from 1.9 to 13.5 cm in diameter. The amount of aspirated fluid varied from 3 to 780 ml. A 18-21 gauge aspiration needles were used for all patients. A 25.0% cyst volume replacement with 99.7% ethanol was approved to be appropriate. Results: 427 renal cysts in 396 patients were followed up by computed tomographic (CT) or ultrasound for less than 3 months to more than one year duration. The curative effective rate and disappearance rate of the renal cystic cavity in solitary renal cysts were 97% and 82%, respectively. In multiple renal cysts, the corresponding values were 95% and 79%. In polycystic kidneys, the curative rate was 67%. The complications such as local abdominal pain (28 cases) and hematuria (four cases) were observed in this series. There were no fatal complications. Conclusions: CT guided percutaneous renal cyst puncture and ethanol therapy is an useful procedure for the treatment of solitary renal cysts and multiple renal cysts

Technical Note: Motion-perturbation method applied to dosimetry of dynamic MLC target tracking—A proof-of-concept

Energy Technology Data Exchange (ETDEWEB)

Feygelman, Vladimir, E-mail: vladimir.feygelman@moffitt.org; Tonner, Brian; Hunt, Dylan; Zhang, Geoffrey; Moros, Eduardo [Department of Radiation Oncology, Moffitt Cancer Center, Tampa, Florida 33612 (United States); Stambaugh, Cassandra [Department of Physics, University of South Florida, Tampa, Florida 33612 (United States); Nelms, Benjamin E. [Canis Lupus LLC, Merrimac, Wisconsin 53561 (United States)

2015-11-15

Purpose: Previous studies show that dose to a moving target can be estimated using 4D measurement-guided dose reconstruction based on a process called virtual motion simulation, or VMS. A potential extension of VMS is to estimate dose during dynamic multileaf collimator (MLC)-tracking treatments. The authors introduce a modified VMS method and quantify its performance as proof-of-concept for tracking applications. Methods: Direct measurements with a moving biplanar diode array were used to verify accuracy of the VMS dose estimates. A tracking environment for variably sized circular MLC apertures was simulated by sending preprogrammed control points to the MLC while simultaneously moving the accelerator treatment table. Sensitivity of the method to simulated tracking latency (0–700 ms) was also studied. Potential applicability of VMS to fast changing beam apertures was evaluated by modeling, based on the demonstrated dependence of the cumulative dose on the temporal dose gradient. Results: When physical and virtual latencies were matched, the agreement rates (2% global/2 mm gamma) between the VMS and the biplanar dosimeter were above 96%. When compared to their own reference dose (0 induced latency), the agreement rates for VMS and biplanar array track closely up to 200 ms of induced latency with 10% low-dose cutoff threshold and 300 ms with 50% cutoff. Time-resolved measurements suggest that even in the modulated beams, the error in the cumulative dose introduced by the 200 ms VMS time resolution is not likely to exceed 0.5%. Conclusions: Based on current results and prior benchmarks of VMS accuracy, the authors postulate that this approach should be applicable to any MLC-tracking treatments where leaf speeds do not exceed those of the current Varian accelerators.

Immunosuppressant MPA Modulates Tight Junction through Epigenetic Activation of MLCK/MLC-2 Pathway via p38MAPK

Directory of Open Access Journals (Sweden)

Niamat Khan

2015-12-01

Full Text Available Background: Mycophenolic acid (MPA is an important immunosuppressive drug (ISD prescribed to prevent graft rejection in the organ transplanted patients, however, its use is also associated with adverse side effects like sporadic gastrointestinal (GI disturbances. Recently, we reported the MPA induced tight junctions (TJs deregulation which involves MLCK/MLC-2 pathway. Here, we investigated the global histone acetylation as well as gene-specific chromatin signature of several genes associated with TJs regulation in Caco-2 cells after MPA treatment.Results: The epigenetic analysis shows that MPA treatment increases the global histone acetylation levels as well as the enrichment for transcriptional active histone modification mark (H3K4me3 at promoter regions of p38MAPK, ATF-2, MLCK, and MLC-2. In contrast, the promoter region of occludin was enriched for transcriptional repressive histone modification mark (H3K27me3 after MPA treatment. In line with the chromatin status, MPA treatment increased the expression of p38MAPK, ATF-2, MLCK, and MLC-2 both at transcriptional and translational level, while occludin expression was negatively influenced. Interestingly, the MPA induced gene expression changes and functional properties of Caco-2 cells could be blocked by the inhibition of p38MAPK using a chemical inhibitor (SB203580.Conclusions: Collectively, our results highlight that MPA disrupts the structure of TJs via p38MAPK-dependent activation of MLCK/MLC-2 pathway that results in decreased integrity of Caco-2 monolayer. These results led us to suggest that p38MAPK-mediated lose integrity of epithelial monolayer could be the possible cause of GI disturbance (barrier dysfunction in the intestine, leading to leaky style diarrhea observed in the organ-transplanted patients treated with MPA.

Technical Note: Motion-perturbation method applied to dosimetry of dynamic MLC target tracking—A proof-of-concept

International Nuclear Information System (INIS)

Feygelman, Vladimir; Tonner, Brian; Hunt, Dylan; Zhang, Geoffrey; Moros, Eduardo; Stambaugh, Cassandra; Nelms, Benjamin E.

2015-01-01

Purpose: Previous studies show that dose to a moving target can be estimated using 4D measurement-guided dose reconstruction based on a process called virtual motion simulation, or VMS. A potential extension of VMS is to estimate dose during dynamic multileaf collimator (MLC)-tracking treatments. The authors introduce a modified VMS method and quantify its performance as proof-of-concept for tracking applications. Methods: Direct measurements with a moving biplanar diode array were used to verify accuracy of the VMS dose estimates. A tracking environment for variably sized circular MLC apertures was simulated by sending preprogrammed control points to the MLC while simultaneously moving the accelerator treatment table. Sensitivity of the method to simulated tracking latency (0–700 ms) was also studied. Potential applicability of VMS to fast changing beam apertures was evaluated by modeling, based on the demonstrated dependence of the cumulative dose on the temporal dose gradient. Results: When physical and virtual latencies were matched, the agreement rates (2% global/2 mm gamma) between the VMS and the biplanar dosimeter were above 96%. When compared to their own reference dose (0 induced latency), the agreement rates for VMS and biplanar array track closely up to 200 ms of induced latency with 10% low-dose cutoff threshold and 300 ms with 50% cutoff. Time-resolved measurements suggest that even in the modulated beams, the error in the cumulative dose introduced by the 200 ms VMS time resolution is not likely to exceed 0.5%. Conclusions: Based on current results and prior benchmarks of VMS accuracy, the authors postulate that this approach should be applicable to any MLC-tracking treatments where leaf speeds do not exceed those of the current Varian accelerators

Neuropsychological Profile of Children with Subcortical Band Heterotopia

Science.gov (United States)

Spencer-Smith, Megan; Leventer, Richard; Jacobs, Rani; De Luca, Cinzia; Anderson, Vicki

2009-01-01

Aim: Subcortical band heterotopia (SBH) or "double cortex" is a malformation of cortical development resulting from impaired neuronal migration. So far, research has focused on the neurological, neuroimaging, and genetic correlates of SBH. More recently, clinical reports and small sample studies have documented neuropsychological dysfunction in…

The Effects of Modified Constraint-Induced Movement Therapy in Acute Subcortical Cerebral Infarction

OpenAIRE

Yu, Changshen; Wang, Wanjun; Zhang, Yue; Wang, Yizhao; Hou, Weijia; Liu, Shoufeng; Gao, Chunlin; Wang, Chen; Mo, Lidong; Wu, Jialing

2017-01-01

Background: Constraint-induced movement therapy (CIMT) promotes upper extremity recovery post stroke, however, it is difficult to implement clinically due to its high resource demand and safety of the restraint. Therefore, we propose that modified CIMT (mCIMT) be used to treat individuals with acute subcortical infarction. Objective: To evaluate the therapeutic effects of mCIMT in patients with acute subcortical infarction, and investigate the possible mechanisms underlying the effect. ...

A high-resolution probabilistic in vivo atlas of human subcortical brain nuclei.

Science.gov (United States)

Pauli, Wolfgang M; Nili, Amanda N; Tyszka, J Michael

2018-04-17

Recent advances in magnetic resonance imaging methods, including data acquisition, pre-processing and analysis, have benefited research on the contributions of subcortical brain nuclei to human cognition and behavior. At the same time, these developments have led to an increasing need for a high-resolution probabilistic in vivo anatomical atlas of subcortical nuclei. In order to address this need, we constructed high spatial resolution, three-dimensional templates, using high-accuracy diffeomorphic registration of T 1 - and T 2 - weighted structural images from 168 typical adults between 22 and 35 years old. In these templates, many tissue boundaries are clearly visible, which would otherwise be impossible to delineate in data from individual studies. The resulting delineations of subcortical nuclei complement current histology-based atlases. We further created a companion library of software tools for atlas development, to offer an open and evolving resource for the creation of a crowd-sourced in vivo probabilistic anatomical atlas of the human brain.

[Peritoneal cyst. A case report].

Science.gov (United States)

Cervone, P; Boso Caretta, F; Painvain, E; Marchiani, E; Montanino, G

1999-11-01

Cystic mesothelioma is a rare benign tumor of the abdominal and pelvic peritoneum, consisting of solitary or multiple cysts. No more than 130 cases are reported. Several risk factors such as chronic peritoneal irritation, caused by foreign bodies, infection or endometriosis, were hypothesized but the pathogenesis is still unknown. A 51-year menopausal woman was submitted to ultrasonography because of abnormal uterine bleeding. The scan revealed a right ovarian cyst (size 81 x 64 mm) with the feature of serous cyst. In the anamnesis a cystectomy of the right ovary and appendectomy were reported. At laparoscopy, then converted in laparotomy, a cyst arising from peritoneum of the posterior surface of the uterus was found. The right ovary was normal. The histopathological finding was: serous simple cyst of peritoneum. Ultrasonographic diagnosis was not confirmed by surgery; in fact, sometimes, it may be difficult to establish the origin of pelvic cystic mass, from ovary or peritoneum, by ultrasonography. It is mandatory to suggest a laparoscopy and/or laparotomy in case of pelvic cystic mass that does not regress in the time even after administration of oral contraceptives.

Oral foregut cyst in a neonate.

Science.gov (United States)

Rosa, Ana Cláudia Garcia; Hiramatsu, Daniel Martins; de Moraes, Fábio Roberto Ruiz; Passador-Santos, Fabrício; de Araújo, Vera Cavalcanti; Soares, Andresa Borges

2013-11-01

Oral foregut cysts are congenital choristomas that arise in the oral cavity during embryonic development from remnants of foregut-derived epithelium. This is an unusual report of a neonate with a large congenital sublingual cystic lesion, extending superficially from the left ventral tongue to the anterior floor of the mouth, impeding breast-feeding. The differential diagnosis included dermoid cyst, epidermoid cyst, mucous retention cyst, and oral lymphangioma. The treatment of choice was enucleation under general anesthesia. Histology showed a cystic lesion with a ciliated pseudostratified columnar epithelium with numerous goblet cells. Immunohistochemistry was positive for cytokeratin 7 and thyroid transcription factor 1 and negative for cytokeratin 20, resulting in a final diagnosis of an oral foregut cyst. Three weeks after surgery, the tongue had healed with good mobility, and breast-feeding could be established. No recurrence was present at 6 months of follow-up.

Epidermoid cyst in Anterior, Middle

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Kankane Vivek Kumar

2016-09-01

Full Text Available Epidermoid cysts are benign slow growing more often extra-axial tumors that insinuate between brain structures, we present the clinical, imaging, and pathological findings in 35 years old female patients with atypical epidermoid cysts which was situated anterior, middle & posterior cranial fossa. NCCT head revealed hypodense lesion over right temporal and perisylvian region with extension in prepontine cistern with mass effect & midline shift and MRI findings revealed a non-enhancing heterogeneous signal intensity cystic lesion in right frontal & temporal region extending into prepontine cistern with restricted diffusion. Patient was detoriated in night of same day of admission, emergency Fronto-temporal craniotomy with anterior peterousectomy and subtotal resection was done. The histological examination confirms the epidermoid cyst. The timing of ectodermal tissue sequestration during fetal development may account for the occurrence of atypical epidermoid cysts.

CD56 Expression in Odontogenic Cysts and Tumors.

Science.gov (United States)

Jaafari-Ashkavandi, Zohreh; Dehghani-Nazhvani, Ali; Razmjouyi, Faranak

2014-01-01

Background and aims. Odontogenic cysts and tumors have a wide spectrum of clinical characteristics that lead to the different management strategies. Since definite diagnosis is difficult in some cases, it has been suggested that CD56 may be a candidate marker for definitive diagnosis of some odontogenic tumors. The present study was designed to examine CD56 expression in lesions with histopathological similarities. Materials and methods. In this cross-sectional, analytical study the subjects were 22 ameloblastomas, 13 dentigerous cysts, 10 keratocystic odontogenic tumors (KCOT), 4 adenomatoid odontogenic tumors (AOT), 3 orthokeratinized odonto-genic cysts, 3 calcifying odontogenic cysts (COC) and one glandular odontogenic cyst (GOC). All the samples were examined for CD56 immunoreactivity. Data were analyzed using chi-square test. Results. Twenty cases (91%) of ameloblastomas, 3 (75%) AOT, 4 (40%) KCOT and one case of GOC were positive for CD56. None of the dentigerous cysts, COC and orthokeratinized odontogenic cysts was CD56-positive. There was a significant difference in the CD56 expression between ameloblastoma and dentigerous cyst, as well as COC. Also, KCOT showed significantly higher expression than orthokeratinized odontogenic cyst. Conclusion. In this study CD56 expression was limited to the odontogenic tumors and more aggressive cystic lesions. This marker can be a useful aid for distinguishing cysts and tumors from similar lesions.

Fetal goiter and bilateral ovarian cysts

DEFF Research Database (Denmark)

Lassen, Pernille; Sundberg, Karin; Juul, Anders

2008-01-01

by each injection and followed by a gradual reduction of fetal goiter as well as the left ovarian cyst. The right cyst ruptured spontaneously. At 36 weeks + 4 days, the patient underwent elective caesarean section and gave birth to a female, weighing 2,880 g with 1- and 5-min Apgar scores of 10....... The thyroid gland appeared normal in size, and cord blood TSH and free T 4 were both within normal limits. At ultrasound control 6 days later, the right ovarian cyst was not visible, while the left cyst was still present. Thus, our report supports previous findings that fetal goiter can be treated...

Expression of extracellular matrix metalloproteinase inducer in odontogenic cysts.

Science.gov (United States)

Ali, Mohammad Abdulhadi Abbas

2008-08-01

Extracellular matrix metalloproteinase inducer (EMMPRIN) is known to induce matrix metalloproteinase (MMP) production. The expression of EMMPRIN in odontogenic cysts has not been previously studied. This study was done to determine the presence and the variability of EMMPRIN expression in various types of odontogenic cysts. An immunohistochemical study using a polyclonal anti-EMMPRIN antibody was done using 48 odontogenic cyst cases: 13 odontogenic keratocysts (OKCs), 18 dentigerous cysts (DCs), and 17 periapical cysts (PAs). Twelve cases of normal dental follicles (DFs) were also included in this study for comparison. EMMPRIN immunoreactivity was detected in all of the cysts and DFs studied. In odontogenic cysts, EMMPRIN immunoreactivity was generally higher in basal cells than in suprabasal cells. The overall EMMPRIN expression in the epithelial lining of the 3 different types of odontogenic cyst was significantly higher than in the DFs. Overall EMMPRIN expression was also found to be significantly higher in the epithelial lining of OKCs than in the other types of cysts. This study confirmed that EMMPRIN is present in odontogenic cysts and DFs. The higher EMMPRIN expression in OKCs suggests that it may be involved in the aggressive behavior of this type of cyst.

Primary pelvic hydatic cyst mimicking ovarian carcinoma

OpenAIRE

Faruk Abike; Ilkkan Dunder; Omer Lutfi Tapisiz; Osman Temizkan; Banu Bingol; Ahmet Payasli; Lale Kutluay

2011-01-01

Hydatic cyst is an illness that appears in consequence of the cystic form of small strap-shaped worm Echinococcus granulosis. Frequently, cysts exist in the lungs and liver. Peritoneal involvement is rare, and generally occurs as a result of second inoculation from rupture of a liver-located hydatic cyst. Primary ovarian hydatic cyst is very rare. A 56-year-old female patient was admitted to Emergency Service with the complaint of stomachache and swollen abdomen. From ultrasonographic examina...

Squamous-lined cyst of the pancreas: Radiological–pathological correlation

International Nuclear Information System (INIS)

Kubo, T.; Takeshita, T.; Shimono, T.; Hashimoto, S.; Miki, Y.

2014-01-01

Pancreatic cystic lesions are increasingly being detected incidentally because of the increased use of cross-sectional imaging. Squamous-lined cysts of the pancreas (lymphoepithelial cyst, epidermoid cyst, and dermoid cyst) are rare cystic lesions lined with squamous epithelium. Distinguishing squamous-lined cysts from other cystic lesions of the pancreas is important to avoid unnecessary surgery, because squamous-lined cysts of the pancreas have no malignant potential. The purpose of this review is to describe findings on computed tomography and magnetic resonance imaging and the histopathological characteristics of squamous-lined cysts, and to summarize the key points of differential diagnosis for pancreatic cystic lesions

Large-scale cortico-subcortical functional networks in focal epilepsies: The role of the basal ganglia

Directory of Open Access Journals (Sweden)

Eva Výtvarová

2017-01-01

Significance: Focal epilepsies affect large-scale brain networks beyond the epileptogenic zones. Cortico-subcortical functional connectivity disturbance was displayed in LTLE, FLE, and POLE. Significant changes in the resting-state functional connectivity between cortical and subcortical structures suggest an important role of the BG and thalamus in focal epilepsies.

Mesenchymal neoplasia and congenital pulmonary cysts

International Nuclear Information System (INIS)

Weinberg, A.G.; Currarino, G.; Moore, G.C.; Votteler, T.P.

1980-01-01

A malignant mesenchymoma exibiting a varied spectrum of differentation developed within a congenital pulmonary cyst 6 1/2 years after the cyst was first recognized. Related tumors with a similar gross appearance have been previously described and have included rhabdomyosarcomas and so-called pulmonary blastomas. There is a low but distinct risk for the developement of mesenchymal sarcomas within congenital peripheral pulmonary cysts. (orig.) [de

Dosimetric evaluation of photon dose calculation under jaw and MLC shielding

International Nuclear Information System (INIS)

Fogliata, A.; Clivio, A.; Vanetti, E.; Nicolini, G.; Belosi, M. F.; Cozzi, L.

2013-01-01

Purpose: The accuracy of photon dose calculation algorithms in out-of-field regions is often neglected, despite its importance for organs at risk and peripheral dose evaluation. The present work has assessed this for the anisotropic analytical algorithm (AAA) and the Acuros-XB algorithms implemented in the Eclipse treatment planning system. Specifically, the regions shielded by the jaw, or the MLC, or both MLC and jaw for flattened and unflattened beams have been studied.Methods: The accuracy in out-of-field dose under different conditions was studied for two different algorithms. Measured depth doses out of the field, for different field sizes and various distances from the beam edge were compared with the corresponding AAA and Acuros-XB calculations in water. Four volumetric modulated arc therapy plans (in the RapidArc form) were optimized in a water equivalent phantom, PTW Octavius, to obtain a region always shielded by the MLC (or MLC and jaw) during the delivery. Doses to different points located in the shielded region and in a target-like structure were measured with an ion chamber, and results were compared with the AAA and Acuros-XB calculations. Photon beams of 6 and 10 MV, flattened and unflattened were used for the tests.Results: Good agreement between calculated and measured depth doses was found using both algorithms for all points measured at depth greater than 3 cm. The mean dose differences (±1SD) were −8%± 16%, −3%± 15%, −16%± 18%, and −9%± 16% for measurements vs AAA calculations and −10%± 14%, −5%± 12%, −19%± 17%, and −13%± 14% for Acuros-XB, for 6X, 6 flattening-filter free (FFF), 10X, and 10FFF beams, respectively. The same figures for dose differences relative to the open beam central axis dose were: −0.1%± 0.3%, 0.0%± 0.4%, −0.3%± 0.3%, and −0.1%± 0.3% for AAA and −0.2%± 0.4%, −0.1%± 0.4%, −0.5%± 0.5%, and −0.3%± 0.4% for Acuros-XB. Buildup dose was overestimated with AAA, while Acuros-XB gave

Clinicopathological findings in symptomatic Rathke's cleft cyst. Correlation between enhancement effects on MRI and histopathology of the cyst wall

International Nuclear Information System (INIS)

Niwa, Jun; Tanabe, Sumiyoshi; Ibayashi, Yukihiro; Hashi, Kazuo; Satoh, Masaaki

1996-01-01

We have studied MR images and the histopathology of eight patients with symptomatic Rathke's cleft cysts. Six cases showed visual disturbance and two showed galactorrhea. In five, the cyst fluid had low signal intensity on T1-weighted images and high intensity on T2-weighted images; in 2, the cyst fluid had high intensity on both T1- and T2-weighted images; in 1, the cyst fluid had high intensity on T1-weighted images and low intensity on T2-weighted images. Enhancement of the cyst wall by Gd-DTPA was able to be distinguished in 6 patients: 2 showed no enhancement, 2 showed thin enhancement and the remaining 2, thick enhancement. Fluid aspiration and total resection of the cyst wall was performed in all patients (3 by the transcranial approach and 5 by the transsphenoidal approach). Normal pituitary glands were found in all cases during the operations. Histopathologically, ciliated epithelium with goblet cells was recognized in 3. Non-ciliated epithelium was recognized in the other 5. Stratified squamous component was recognized in 1 and secondary inflammation, in another. Normal pituitary tissue was recognized in 5. Immunohistochemically, ciliated and non-ciliated epithelium was successfully stained for detecting antibody against epithelial membrane antigen and/or carcinoembryonic antigen. Two cases with no enhancement of the cyst wall by Gd-DTPA showed only ciliated epithelium. Two patients with thin enhancement of the cyst wall had single layer epithelium with normal pituitary tissue. Two patients with thick enhancement of the cyst wall showed single layer epithelium with its stratified squamous component or with secondary inflammation. A close relationship was suggested between the enhancement effect on MRI and histopathology of the cyst wall. (author)

Follow-up of pineal cysts in children. Is it necessary?

Energy Technology Data Exchange (ETDEWEB)

Jussila, Miro-Pekka [Oulu University Hospital and University of Oulu, Department of Diagnostic Radiology, Oulu (Finland); Oulu University Hospital and University of Oulu, Department of Children and Adolescents, Oulu (Finland); Olsen, Paeivi [Oulu University Hospital and University of Oulu, Department of Children and Adolescents, Oulu (Finland); University of Oulu, PEDEGO Research Group, Medical Research Center, Oulu (Finland); Salokorpi, Niina [Oulu University Hospital and University of Oulu, Department of Neurosurgery, Oulu (Finland); University of Oulu, Medical Research Center, Oulu (Finland); Suo-Palosaari, Maria [Oulu University Hospital and University of Oulu, Department of Diagnostic Radiology, Oulu (Finland); University of Oulu, Medical Research Center, Oulu (Finland)

2017-12-15

Pineal cysts are common incidental findings in children undergoing magnetic resonance imaging (MRI). Several studies have suggested MRI follow-up if the cyst is larger than 10 mm. However, cysts do not usually change during follow-up. Prevalence, growth, and structure of the pineal cysts were analyzed to decide if follow-up MRI is necessary. A retrospective review between 2010 and 2015 was performed using 3851 MRI examinations of children aged 0-16 years to detect pineal cysts having a maximum diameter ≥ 10 mm. Eighty-one children with pineal cysts were identified and 79 of them had been controlled by MRI. Cysts were analyzed for the size, growth, and structure. A total of 1.8% of the children had a pineal cyst with a diameter ≥ 10 mm. Cysts were present in 48 girls (59.3%) and 33 boys (40.7%). Most pineal cysts (70/79) did not significantly grow during the follow-up (median 10 months, range 3-145 months). A total of 11.4% (9/79) of the cysts grew with the biggest change measured from the outer cyst wall sagittal anteroposterior dimension (mean 3.4 mm ± 1.7 mm). Only one cyst grew more than 5 mm. We found no factors correlating with the cyst growth among 9 cysts that grew > 2 mm. A majority of pineal cysts remained unchanged during the MRI follow-up. Results of this study suggest that routine MRI follow-up of pineal cysts is not necessary in the absence of unusual radiological characteristics or related clinical symptoms. (orig.)

Snapping Knee Caused by Medial Meniscal Cyst

Directory of Open Access Journals (Sweden)

Tsuyoshi Ohishi

2014-01-01

Full Text Available Snapping phenomenon around the medial aspect of the knee is rare. We present this case of snapping knee caused by the sartorius muscle over a large medial meniscal cyst in a 66-year-old female. Magnetic resonance images demonstrated a large medial meniscal cyst with a horizontal tear of the medial meniscus. Arthroscopic cyst decompression with limited meniscectomy resulted in the disappearance of snapping, and no recurrence of the cyst was observed during a 2-year follow-up period.

Primary Hydatid Cyst of the Neck

International Nuclear Information System (INIS)

Mujtaba, S. S.; Faridi, N.; Haroon, S.

2013-01-01

Hydatid cysts in the neck are relatively exceptional, even in areas where Echinococcus granulosis is endemic, such as Asia. Although liver and lung are frequent sites of involvement, it can involve all tissues, with neck remaining one of the most rare sites. It should come in the differential diagnosis of cystic lesion of neck, as the treatment options differ widely from common neck cysts. The role of radiological investigation is important and, in these cases, the involvement of other organs should be investigated. Serological tests may be helpful. The major treatment modality is surgical and the cyst should be excised as a whole, without being ruptured, to prevent any treatment complications, as the cyst fluid can initiate an anaphylactic reaction. Postoperative albendazole therapy is recommended particularly when there is intra-operative spillover. We report a case of an isolated hydatid cyst localized in the anterior triangle of the neck without any pulmonary or hepatic involvement. (author)

TH-AB-202-03: A Novel Tool for Computing Deliverable Doses in Dynamic MLC Tracking Treatments

Energy Technology Data Exchange (ETDEWEB)

Fast, M; Kamerling, C; Menten, M; Nill, S; Oelfke, U [The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London (United Kingdom); Crijns, S; Raaymakers, B [University Medical Center Utrecht, Utrecht (Netherlands)

2016-06-15

Purpose: In tracked dynamic multi-leaf collimator (MLC) treatments, segments are continuously adapted to the target centroid motion in beams-eye-view. On-the-fly segment adaptation, however, potentially induces dosimetric errors due to the finite MLC leaf width and non-rigid target motion. In this study, we outline a novel tool for computing the 4d dose of lung SBRT plans delivered with MLC tracking. Methods: The following automated workflow was developed: A) centroid tracking, where the initial segments are morphed to each 4dCT phase based on the beams-eye-view GTV shift (followed by a dose calculation on each phase); B) re-optimized tracking, in which all morphed initial plans from (A) are further optimised (“warm-started”) in each 4dCT phase using the initial optimisation parameters but phase-specific volume definitions. Finally, both dose sets are accumulated to the reference phase using deformable image registration. Initial plans were generated according to the RTOG-1021 guideline (54Gy, 3-Fx, equidistant 9-beam IMRT) on the peak-exhale (reference) phase of a phase-binned 4dCT. Treatment planning and delivery simulations were performed in RayStation (research v4.6) using our in-house segment-morphing algorithm, which directly links to RayStation through a native C++ interface. Results: Computing the tracking plans and 4d dose distributions via the in-house interface takes 5 and 8 minutes respectively for centroid and re-optimized tracking. For a sample lung SBRT patient with 14mm peak-to-peak motion in sup-inf direction, mainly perpendicular leaf motion (0-collimator) resulted in small dose changes for PTV-D95 (−13cGy) and GTV-D98 (+18cGy) for the centroid tracking case compared to the initial plan. Modest reductions of OAR doses (e.g. spinal cord D2: −11cGy) were achieved in the idealized tracking case. Conclusion: This study presents an automated “1-click” workflow for computing deliverable MLC tracking doses in RayStation. Adding a non

TH-AB-202-03: A Novel Tool for Computing Deliverable Doses in Dynamic MLC Tracking Treatments

International Nuclear Information System (INIS)

Fast, M; Kamerling, C; Menten, M; Nill, S; Oelfke, U; Crijns, S; Raaymakers, B

2016-01-01

Purpose: In tracked dynamic multi-leaf collimator (MLC) treatments, segments are continuously adapted to the target centroid motion in beams-eye-view. On-the-fly segment adaptation, however, potentially induces dosimetric errors due to the finite MLC leaf width and non-rigid target motion. In this study, we outline a novel tool for computing the 4d dose of lung SBRT plans delivered with MLC tracking. Methods: The following automated workflow was developed: A) centroid tracking, where the initial segments are morphed to each 4dCT phase based on the beams-eye-view GTV shift (followed by a dose calculation on each phase); B) re-optimized tracking, in which all morphed initial plans from (A) are further optimised (“warm-started”) in each 4dCT phase using the initial optimisation parameters but phase-specific volume definitions. Finally, both dose sets are accumulated to the reference phase using deformable image registration. Initial plans were generated according to the RTOG-1021 guideline (54Gy, 3-Fx, equidistant 9-beam IMRT) on the peak-exhale (reference) phase of a phase-binned 4dCT. Treatment planning and delivery simulations were performed in RayStation (research v4.6) using our in-house segment-morphing algorithm, which directly links to RayStation through a native C++ interface. Results: Computing the tracking plans and 4d dose distributions via the in-house interface takes 5 and 8 minutes respectively for centroid and re-optimized tracking. For a sample lung SBRT patient with 14mm peak-to-peak motion in sup-inf direction, mainly perpendicular leaf motion (0-collimator) resulted in small dose changes for PTV-D95 (−13cGy) and GTV-D98 (+18cGy) for the centroid tracking case compared to the initial plan. Modest reductions of OAR doses (e.g. spinal cord D2: −11cGy) were achieved in the idealized tracking case. Conclusion: This study presents an automated “1-click” workflow for computing deliverable MLC tracking doses in RayStation. Adding a non

Bilateral nasolabial cysts associated with recurrent dacryocystitis.

Science.gov (United States)

Kyrmizakis, Dionysios E; Lachanas, Vassilios A; Benakis, Antonios A; Velegrakis, George A; Aslanides, Ioannis M

2005-05-01

Nasolabial cysts are rare, nonodontogenic, soft-tissue, developmental cysts occurring inferior to the nasal alar region. They are thought to arise from remnants of the nasolacrimal ducts and they are frequently asymptomatic. We report a rare case of bilateral nasolabial cysts accompanied by bilateral chronic dacryocystitis. A 48-year-old woman suffering from bilateral chronic dacryocystitis was referred to our department for endonasal dacryocystorhinostomy. She had undergone external dacryocystorhinostomy on the left side a few years earlier. Physical examination and computed tomography scan revealed nasolabial cysts bilaterally inferior to the nasal alar region. The cysts were removed via a sublabial approach and endoscopic dacryocystorhinostomy was performed on the right side. Ten months after surgery, the patient was asymptomatic. There may be a correlation, due to embryological reasons, between the presence of nasolabial cysts and the presence of chronic dacryocystitis. Both can be corrected surgically, under the same anaesthesia, without visible scar formation.

Application of Intraoperative Ultrasonography for Guiding Microneurosurgical Resection of Small Subcortical Lesions

International Nuclear Information System (INIS)

Wang, Jia; Duan, Yun You; Liu, Xi; Wang, Yu; Gao, Guo Dong; Qin, Huai Zhou; Wang, Liang

2011-01-01

We wanted to evaluate the clinical value of intraoperative ultrasonography for real-time guidance when performing microneurosurgical resection of small subcortical lesions. Fifty-two patients with small subcortical lesions were involved in this study. The pathological diagnoses were cavernous hemangioma in 25 cases, cerebral glioma in eight cases, abscess in eight cases, small inflammatory lesion in five cases, brain parasite infection in four cases and the presence of an intracranial foreign body in two cases. An ultrasonic probe was sterilized and lightly placed on the surface of the brain during the operation. The location, extent, characteristics and adjacent tissue of the lesion were observed by high frequency ultrasonography during the operation. All the lesions were located in the cortex and their mean size was 1.3 ± 0.2 cm. Intraoperative ultrasonography accurately located all the small subcortical lesions, and so the neurosurgeon could provide appropriate treatment. Different lesion pathologies presented with different ultrasonic appearances. Cavernous hemangioma exhibited irregular shapes with distinct margins and it was mildly hyperechoic or hyperechoic. The majority of the cerebral gliomas displayed irregular shapes with indistinct margins, and they often showed cystic and solid mixed echoes. Postoperative imaging identified that the lesions had completely disappeared, and the original symptoms of all the patients were significantly alleviated. Intraoperative ultrasonography can help accurately locate small subcortical lesions and it is helpful for selecting the proper approach and guiding thorough resection of these lesions.

Application of Intraoperative Ultrasonography for Guiding Microneurosurgical Resection of Small Subcortical Lesions

Energy Technology Data Exchange (ETDEWEB)

Wang, Jia; Duan, Yun You; Liu, Xi; Wang, Yu; Gao, Guo Dong; Qin, Huai Zhou; Wang, Liang [Tangdu Hospital of the Fourth Military Medicine University, Xi an (China)

2011-10-15

We wanted to evaluate the clinical value of intraoperative ultrasonography for real-time guidance when performing microneurosurgical resection of small subcortical lesions. Fifty-two patients with small subcortical lesions were involved in this study. The pathological diagnoses were cavernous hemangioma in 25 cases, cerebral glioma in eight cases, abscess in eight cases, small inflammatory lesion in five cases, brain parasite infection in four cases and the presence of an intracranial foreign body in two cases. An ultrasonic probe was sterilized and lightly placed on the surface of the brain during the operation. The location, extent, characteristics and adjacent tissue of the lesion were observed by high frequency ultrasonography during the operation. All the lesions were located in the cortex and their mean size was 1.3 {+-} 0.2 cm. Intraoperative ultrasonography accurately located all the small subcortical lesions, and so the neurosurgeon could provide appropriate treatment. Different lesion pathologies presented with different ultrasonic appearances. Cavernous hemangioma exhibited irregular shapes with distinct margins and it was mildly hyperechoic or hyperechoic. The majority of the cerebral gliomas displayed irregular shapes with indistinct margins, and they often showed cystic and solid mixed echoes. Postoperative imaging identified that the lesions had completely disappeared, and the original symptoms of all the patients were significantly alleviated. Intraoperative ultrasonography can help accurately locate small subcortical lesions and it is helpful for selecting the proper approach and guiding thorough resection of these lesions.

The Baker's cyst - a diagnostic problem

International Nuclear Information System (INIS)

Meydam, K.

1981-01-01

Precise definition of Baker's cyst has been prevented by variety of synonyms. Following anatomical description, Baker's determination, and investigations of myself one should differentiate between the rupture of capsule, bursa semimembranos-gastrocnemia, and Baker's cyst because thea are clearly independent from the pathologic-anatomical point of view. Clinical importance of Baker's cyst in connection with further diseases of the knee joint and therapeutical possibilities are discussed. (orig.) [de

Prevalence of odontogenic cysts and tumors among UAE population

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Natheer Hashim Al-Rawi

2013-01-01

Full Text Available Background: Odontogenic cysts and tumors are lesions that tend to arise from the tooth apparatus or its remnants. Odontogenic cysts and tumors constitute an important aspect of oral maxillofacial pathology as they can be diagnosed in general dental practice. Aim: The purpose of this study was to evaluate the prevalence of odontogenic cysts and tumors diagnosed in the UAE and to compare the results with findings in the literature. Materials and Methods: Data of odontogenic cysts diagnosed between 1990 and 2010 were collected from the files of the Oral Pathology Laboratory and Oral Surgery Department of Tawam Hospital, UAE. Results: Most of the prevalent odontogenic cysts are radicular cysts (69.1% - followed by dentigerous cysts (7.9%. Among the odontogenic tumors, the most prevalent is odontoma (12.2% followed by ameloblastoma (2.9%. The middle and posterior mandible was the most common anatomic site for the formation of cysts and tumors. In fact, 93.4% of patients over 40 years presented with odontogenic cysts, whereas 6.3% presented with odontogenic tumor. Odontoma as odontogenic tumor was seen mostly in the first and second decades of life. Conclusion: The prevalence of odontogenic cysts was similar to that reported in the literature, with inflammatory cysts occurring most frequently.

Ventriculoperitoneal shunt blockage by hydatid cyst

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Abrar A Wani

2013-01-01

Full Text Available Ventriculoperitoneal (VP shunt is one of the commonest procedures done in neurosurgical practice throughout the world. One of the commonest problems after putting the VP shunt is the shunt obstruction, which can be due to varied causes. Shunt obstruction secondary to the parasitic infections is rarely seen. We are presenting a 15-year-old child, a case of operated cerebral hydatid cyst with hydrocephalus. She presented with shunt malfunction after 1 year of surgical excision of the hydatid cyst. Revision of the VP shunt was done and peroperatively, it was found that the shunt tubing was obstructed due to small hydatid cysts. This is the first reported case of VP shunt obstruction by hydatid cyst.

SU-F-T-271: Comparing IMRT QA Pass Rates Before and After MLC Calibration

Energy Technology Data Exchange (ETDEWEB)

Mazza, A; Perrin, D; Fontenot, J [Mary Bird Perkins Cancer Center, Baton Rouge, LA (United States)

2016-06-15

Purpose: To compare IMRT QA pass rates before and after an in-house MLC leaf calibration procedure. Methods: The MLC leaves and backup jaws on four Elekta linear accelerators with MLCi2 heads were calibrated using the EPID-based RIT Hancock Test as the means for evaluation. The MLCs were considered to be successfully calibrated when they could pass the Hancock Test with criteria of 1 mm jaw position tolerance, and 1 mm leaf position tolerance. IMRT QA results were collected pre- and postcalibration and analyzed using gamma analysis with 3%/3mm DTA criteria. AAPM TG-119 test plans were also compared pre- and post-calibration, at both 2%/2mm DTA and 3%/3mm DTA. Results: A weighted average was performed on the results for all four linear accelerators. The pre-calibration IMRT QA pass rate was 98.3 ± 0.1%, compared with the post-calibration pass rate of 98.5 ± 0.1%. The TG-119 test plan results showed more of an improvement, particularly at the 2%/2mm criteria. The averaged results were 89.1% pre and 96.1% post for the C-shape plan, 94.8% pre and 97.1% post for the multi-target plan, 98.6% pre and 99.7% post for the prostate plan, 94.7% pre and 94.8% post for the head/neck plan. Conclusion: The patient QA results did not show statistically significant improvement at the 3%/3mm DTA criteria after the MLC calibration procedure. However, the TG-119 test cases did show significant improvement at the 2%/2mm level.

Diagnosing aneurysmal and unicameral bone cysts with magnetic resonance imaging.

Science.gov (United States)

Sullivan, R J; Meyer, J S; Dormans, J P; Davidson, R S

1999-09-01

The differential between aneurysmal bone cysts and unicameral bone cysts usually is clear clinically and radiographically. Occasionally there are cases in which the diagnosis is not clear. Because natural history and treatment are different, the ability to distinguish between these two entities before surgery is important. The authors reviewed, in a blinded fashion, the preoperative magnetic resonance images to investigate criteria that could be used to differentiate between the two lesions. All patients had operative or pathologic confirmation of an aneurysmal bone cyst or unicameral bone cyst. The authors analyzed the preoperative magnetic resonance images of 14 patients with diagnostically difficult bone cysts (eight children with unicameral bone cysts and six children with aneurysmal bone cysts) and correlated these findings with diagnosis after biopsy or cyst aspiration and contrast injection. The presence of a double density fluid level within the lesion strongly indicated that the lesion was an aneurysmal bone cyst, rather than a unicameral bone cyst. Other criteria that suggested the lesion was an aneurysmal bone cyst were the presence of septations within the lesion and signal characteristics of low intensity on T1 images and high intensity on T2 images. The authors identified a way of helping to differentiate between aneurysmal bone cysts and unicameral bone cysts on magnetic resonance images. Double density fluid level, septation, and low signal on T1 images and high signal on T2 images strongly suggest the bone cyst in question is an aneurysmal bone cyst, rather than a unicameral bone cyst. This may be helpful before surgery for the child who has a cystic lesion for which radiographic features do not allow a clear differentiation of unicameral bone cyst from aneurysmal bone cyst.

Ultrasonographic findings of omental and mesnenteric cysts

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Kang, Jin Wha; Kim, I W; Yeon, K M; Kim, C W [Seoul National University College of Medicine, Seoul (Korea, Republic of)

1989-12-15

Omental and mesenteric cysts are uncommon diseases mostly occurring in young children. They are felt to have a common origin from obstructed or ectopic lymphatics. We reviewed three cases of omental cyst and three cases of mesenteric cyst. Sonography showed cystic mass with a thin wall and multiple thin septi dividing the cyst into multiple irregular spaces. In most cases(5/6) solid portions were detected and they were proved to be tissue debris and hemorrhagic clots. Fluid content was either anechoic or echogenic. Floating echogenicities or fluid-fluid level were detected in some cases. Ultrasound is very useful in the diagnosis of omental and mesenteric cysts in children, giving reliable information relating to internal hemorrhage, infection or adhesion to adjacent organs

Recurrent intramedullary epidermoid cyst of conus medullaris.

LENUS (Irish Health Repository)

Fleming, Christina

2011-01-01

Spinal intramedullary epidermoid cyst is a rare condition. Recurrent epidermoid cyst in the spine cord is known to occur. The authors describe a case of recurrent conus medullaris epidermoid cyst in a 24-year-old female. She initially presented at 7 years of age with bladder disturbance in the form of diurnal enuresis and recurrent urinary tract infection. MRI lumbar spine revealed a 4 cm conus medullaris epidermoid cyst. Since the initial presentation, the cyst had recurred seven times in the same location and she underwent surgical intervention in the form of exploration and debulking. This benign condition, owing to its anatomical location, has posed a surgical and overall management challenge. This occurrence is better managed in a tertiary-care centre requiring multi-disciplinary treatment approach.

Behavioral and subcortical signatures of musical expertise in Mandarin Chinese speakers.

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Caitlin Dawson

Full Text Available Both musical training and native language have been shown to have experience-based plastic effects on auditory processing. However, the combined effects within individuals are unclear. Recent research suggests that musical training and tone language speaking are not clearly additive in their effects on processing of auditory features and that there may be a disconnect between perceptual and neural signatures of auditory feature processing. The literature has only recently begun to investigate the effects of musical expertise on basic auditory processing for different linguistic groups. This work provides a profile of primary auditory feature discrimination for Mandarin speaking musicians and nonmusicians. The musicians showed enhanced perceptual discrimination for both frequency and duration as well as enhanced duration discrimination in a multifeature discrimination task, compared to nonmusicians. However, there were no differences between the groups in duration processing of nonspeech sounds at a subcortical level or in subcortical frequency representation of a nonnative tone contour, for fo or for the first or second formant region. The results indicate that musical expertise provides a cognitive, but not subcortical, advantage in a population of Mandarin speakers.

MR imaging of mediastinal foregut cysts

International Nuclear Information System (INIS)

LeBlanc, J.; Guttentag, A.R.; McLoud, T.C.; Shepard, J.O.

1991-01-01

This paper reports on the diagnosis of mediastinal foregut cysts which are difficult to establish even with CT, because these lesions often have high attenuation numbers similar to tumors. This study was undertaken to determine the value of MR imaging in the diagnosis of foregut cysts. MR imaging of 58 mediastinal masses was performed between 1986 and 1991 at 0.5 T, with T1- and T2-weighted images obtained. Seven foregut cysts were identified. Five were pathologically proven; in two cases the diagnosis was based on clinical findings and radiologic stability. Signal characteristics were compared with those of 52 pathologically proven mediastinal masses: six thymomas, 10 thyroid goiters and carcinomas, 11 neurogenic tumors, 15 lymphomas, and 10 miscellaneous masses. Fat and muscle were used as internal standards of signal intensity (SI). All foregut cysts were very bright on T2-weighted images. On T1-weighted sequences, two had low SI, but the remaining five showed high SI. These differences reflected variability in cyst protein content, high SI indicating the presence of mucus. On T1-weighted images, low SI was identified in most other mediastinal masses, but uniform high SI was specific for foregut cysts. Our series did not include any fatty lesions, as these were easily recognized on CT scans

Primary hydatid cyst in gastrocnemius muscle

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Saswata Bharati

2012-01-01

Full Text Available Cystic echinococcosis, which is caused by the larval stages of Echinococcus granulosus, results from the presence of one or more massive cysts or hydatids, and can involve any organ, including the liver, lungs, heart, brain, kidneys, and long bones. Muscle hydatidosis is usually secondary in nature, resulting from spread of larval tissue from a primary site after spontaneous or trauma-induced cyst rupture or after release of viable parasite material during invasive treatment procedures. Primary muscle hydatidosis is extremely uncommon, because implantation at this site would require passage through the filters of the liver and lung. Intramuscular hydatid cyst can cause a variety of diagnostic problems, especially in the absence of typical radiologic findings. We present an unusual case of a primary hydatid cyst found in the popliteal fossa of the right knee of a 52-year-old woman, presenting as an enlarging soft-tissue tumor for 6 months associated with pain. The mass initially was diagnosed to be Backer′s cyst by ultrasonography, but later it was confirmed postoperatively through histopathological studies to be due to hydatid disease. In regions where hydatidosis is endemic, hydatid cyst should be included in the differential diagnosis of any unusual muscular mass.

POST-TRAUMATIC GLUTEAL CYST: REPORT OF A CASE

African Journals Online (AJOL)

emmys

Cysts are among the common benign soft tissue lesions that affect many people world wide. A cyst is a collection of fluid in a sac, when it is lined by epithelium or endothelium, it is called a true cyst, when the sac is lined by granulation tissue it called a false cyst 1. The true lining may be destroyed and replaced by ...

Squamous cell carcinoma arising in an odontogenic cyst

International Nuclear Information System (INIS)

Yu, Jae Jung; Hwang, Eui Hwan; Lee, Sang Rae; Choi, Jeong Hee

2003-01-01

Squamous cell carcinoma arising in an odontogenic cyst is uncommon. The diagnosis of carcinoma arising in a cyst requires that there must be an area of microscopic transition from the benign epithelial cyst lining to the invasive squamous cell carcinoma. We report a histopathologically proven case of squamous cell carcinoma arising in a residual mandibular cyst in a 54-year-old woman.

Caveolin-1 expression in odontogenic cysts and ameloblastomas.

Science.gov (United States)

Jaafari-Ashkavandi, Zohreh; Pardis, Soheil; Asadzadeh, Maryam; Andisheh-Tadbir, Azadeh; Dehghani-Nazhvani, Ali

2014-01-01

The aim of this study is to evaluate the caveolin-1 expression in a group of odontogenic cysts and tumors. In this cross-sectional study, the expression of caveolin-1 was evaluated immunohistochemically in 75 samples including 18 cases of dentigerous cyst, 18 odontogenic keratocysts, 3 orthokeratinized odontogenic cysts, 2 calcifying odontogenic cysts and 34 ameloblastomas (solid and unicystic). Positive immunohistochemical reaction was found in 100% of odontogenic cysts and this was significantly more than both unicystic (65%) and solid (55%) ameloblastomas. The present study showed the expression of caveolin-1 in all odontogenic cysts and more than ameloblastomas. The results suggested that absence of caveolin-1 might enhance aggressiveness of odontogenic lesions and could be a useful marker for distinguishing ameloblastomas from other odontogenic lesions.

Disruptions in cortico-subcortical covariance networks associated with anxiety in new-onset childhood epilepsy

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Camille Garcia-Ramos

2016-01-01

Full Text Available Anxiety disorders represent a prevalent psychiatric comorbidity in both adults and children with epilepsy for which the etiology remains controversial. Neurobiological contributions have been suggested, but only limited evidence suggests abnormal brain volumes particularly in children with epilepsy and anxiety. Since the brain develops in an organized fashion, covariance analyses between different brain regions can be investigated as a network and analyzed using graph theory methods. We examined 46 healthy children (HC and youth with recent onset idiopathic epilepsies with (n = 24 and without (n = 62 anxiety disorders. Graph theory (GT analyses based on the covariance between the volumes of 85 cortical/subcortical regions were investigated. Both groups with epilepsy demonstrated less inter-modular relationships in the synchronization of cortical/subcortical volumes compared to controls, with the epilepsy and anxiety group presenting the strongest modular organization. Frontal and occipital regions in non-anxious epilepsy, and areas throughout the brain in children with epilepsy and anxiety, showed the highest centrality compared to controls. Furthermore, most of the nodes correlating to amygdala volumes were subcortical structures, with the exception of the left insula and the right frontal pole, which presented high betweenness centrality (BC; therefore, their influence in the network is not necessarily local but potentially influencing other more distant regions. In conclusion, children with recent onset epilepsy and anxiety demonstrate large scale disruptions in cortical and subcortical brain regions. Network science may not only provide insight into the possible neurobiological correlates of important comorbidities of epilepsy, but also the ways that cortical and subcortical disruption occurs.

Dentigerous Cyst Associated with a Mesiodens: A Case Report

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Sepideh Vosough Hosseini

2011-06-01

Full Text Available Dentigerous cysts are the second most common odontogenic cysts after radicular cysts and are most commonly seen in association with third molars and maxillary canines. Only 5% of dentigerous cysts involve supernumerary teeth, of which mesiodens is the most frequent type. This paper presents a case of dentigerous cyst associated with a mesiodens that caused a painless swelling in the upper lip of an 18-year-old female. The patient was treated surgically by enucleation of total cyst and surgical extraction of mesiodens under local anesthesia.

Meningeal cysts in the sacral canal

International Nuclear Information System (INIS)

Salatkova, A.; Matejka, J.

1996-01-01

Meningeal cysts develop from the meningeal cover, contain liquor, are localised in the spinal canal. Clinical demonstration are different, often with no clinical manifestation, or with manifestation from compression surrounding structures. Meningeal cysts is possible diagnostic imaging with perimyelography, CT and MRI. In the paper it was discussed different feature in the diagnosis meningeal cysts with perimyelography and CT of the spine, position and time of the examination.(authors). 7 figs., 11 refs

Bilateral nasolabial cysts - case report and review of literature

International Nuclear Information System (INIS)

Patil, Aruna R; Singh, Abhinav Pratap; Nandikoor, Shrivalli; Meganathan, Prabhu

2016-01-01

Nasolabial cyst is a non-odontogenic, extraosseous, soft tissue cyst, commonly unilateral, located in the nasolabial fold. Bilateral nasolabial cysts are of rare occurrence. This case report describes the multimodality imaging appearance of bilateral nasolabial cysts with a review of literature

Modified PAIR Technique for Percutaneous Treatment of High-Risk Hydatid Cysts

Energy Technology Data Exchange (ETDEWEB)

Gabal, Abdelwahab M., E-mail: gabalrad@yahoo.com [King Fahad Hospital, Department of Radiology (Saudi Arabia); Khawaja, Fazal I. [King Fahad Hospital, Department of Gastroenterology and Gastrointestinal Endoscopy (Saudi Arabia); Mohammad, Ghanem A. [Al-azhar University Medical Center, Department of Chest Diseases (Egypt)

2005-04-15

Purpose: This paper presents a modification of the known method for percutaneous treatment of hydatid cyst, the PAIR technique. It aimed to achieve safe aspiration of large symptomatic cysts and cysts with a danger of impending rupture. Methods: We designed a coaxial catheter system to achieve concomitant evacuation of cyst contents while infusing scolicidal agent. Hypertonic saline is used to wash out cyst contents and to kill protoscolices. This was followed by injection of a sclerosant (ethyl alcohol 95%) into the residual cyst cavity to prevent formation of a cyst collection after the procedure. Seventeen cysts in 14 patients were successfully aspirated. Follow-up plain radiographs, ultrasonography and CT were performed weekly in the first 4 weeks and then at 3, 6 and 12 months for all patients. Seven patients (9 drained cysts) were followed up for 2 years and 1 patient for 3 years. Results: All cysts were successfully aspirated. The following morphologic changes were noticed: a gradual decrease in cyst size (17 cysts, 100%), thickening and irregularity of the cyst wall due to separation of endocyst from pericyst (7 cysts, 41%), development of a heterogeneous appearance of the cyst components (8 cysts, 47%) and development of pseudotumor (2 cysts, 12%). None of the treated cysts disappeared completely. No significant procedure-related complications were encountered. Conclusion: This modified PAIR technique is a reliable method for percutaneous treatment of risky and symptomatic hydatid cysts.

Modified PAIR Technique for Percutaneous Treatment of High-Risk Hydatid Cysts

International Nuclear Information System (INIS)

Gabal, Abdelwahab M.; Khawaja, Fazal I.; Mohammad, Ghanem A.

2005-01-01

Purpose. This paper presents a modification of the known method for percutaneous treatment of hydatid cyst, the PAIR technique. It aimed to achieve safe aspiration of large symptomatic cysts and cysts with a danger of impending rupture. Methods. We designed a coaxial catheter system to achieve concomitant evacuation of cyst contents while infusing scolicidal agent. Hypertonic saline is used to wash out cyst contents and to kill protoscolices. This was followed by injection of a sclerosant (ethyl alcohol 95%) into the residual cyst cavity to prevent formation of a cyst collection after the procedure. Seventeen cysts in 14 patients were successfully aspirated. Follow-up plain radiographs, ultrasonography and CT were performed weekly in the first 4 weeks and then at 3, 6 and 12 months for all patients. Seven patients (9 drained cysts) were followed up for 2 years and 1 patient for 3 years. Results. All cysts were successfully aspirated. The following morphologic changes were noticed: a gradual decrease in cyst size (17 cysts, 100%), thickening and irregularity of the cyst wall due to separation of endocyst from pericyst (7 cysts, 41%), development of a heterogeneous appearance of the cyst components (8 cysts, 47%) and development of pseudotumor (2 cysts, 12%). None of the treated cysts disappeared completely. No significant procedure-related complications were encountered. Conclusion. This modified PAIR technique is a reliable method for percutaneous treatment of risky and symptomatic hydatid cysts

Water relations during desiccation of cysts of the potato-cyst nematode Globodera rostochiensis.

Science.gov (United States)

Wharton, D A; Worland, M R

2001-03-01

The loss during desiccation of osmotically active water (OAW), which freezes during cooling to -45 degrees C, and osmotically inactive water (OIW), which remains unfrozen, from the cysts of the potato cyst nematode, Globodera rostochiensis, was determined using differential scanning calorimetry. Exotherms and endotherms associated with non-egg compartments were not detected after 5 min desiccation at 50% relative humidity and 20 degrees C. The pattern of water loss from the cysts indicates that water is lost from compartments outside the eggs first, that nearly all the non-egg water is OAW and that the OIW content of the cyst is contained within the eggs. Water is lost from the eggs only after the OAW content outside the eggs falls below that within the eggs. Both OAW and OIW are lost from the eggs during desiccation but the eggs retain a small amount of OIW. Other animals which survive some desiccation but which are not anhydrobiotic will tolerate the loss of OAW but not the loss of their OIW. Anhydrobiotic animals can survive the loss of both their OAW and a substantial proportion of their OIW.

Hyperdense renal masses: a CT manifestation of hemorrhagic renal cysts

International Nuclear Information System (INIS)

Sussman, S.; Cochran, S.T.; Pagani, J.J.; McArdle, C.; Wong, W.; Austin, R.; Curry, N.; Kelly, K.M.

1984-01-01

Eleven patients with sharply circumscribed round to ovoid renal cysts measuring 70-90 H on CT are reported. The cysts were hyperdense on unenhanced scans, measuring 30-60 H greater than the adjacent parenchyma, and either hypodense, isodense, or hyperdense on enhanced scans. Four patients had polycystic kidney disease; of the other 7 patients, the cysts were cortical in 6 and parapelvic in 1. Eight patients had a solitary cyst and 3 had multiple cysts. Sonography demonstrated internal echoes and/or lack of increased through-transmission in 6 patients. Pathological analysis was available in 6 cases and indicated a benign, hemorrhagic renal cyst. This hyperdense CT appearance is characteristic of some hemorrhagic renal cysts, though differentiation between benign and malignant cysts requires cyst puncture and/or surgery

Immunohistochemical Assessment of Mast Cells and Small Blood Vessels in Dentigerous Cyst, Odontogenic Keratocyst, and Periapical Cyst.

Science.gov (United States)

Kouhsoltani, Maryam; Moradzadeh Khiavi, Monir; Jamali, Golshan; Farnia, Samira

2015-12-01

The aim of this study was to verify the density of mast cells (MCs) and microvessels in odontogenic cysts. Furthermore, the correlation between MCs and microvessels was evaluated to assess the contribution of MCs to angiogenesis and growth of odontogenic cysts. This approach may be a basis for the development of future pharmaceuticals addressed to MCs performance to manage odontogenic cysts. To our knowledge, no study investigating the correlation between MCs and microvessels has been performed to date. 60 cases of odontogenic cysts consisting of 20 radicular cysts (RCs), 20 odontogenic keratocysts (OKCs) and 20 dentigerous cysts (DCs) were included in this study. Five high power fields in superficial connective tissue and five high power fields in deep connective tissue were counted for each sample. Moreover, a total mean of ten fields was calculated. RC showed the highest mean numbers of MCs and microvessels (pcysts contained more MCs and microvessels compared to the deeper zones. A statistically significant correlation between the numbers of MCs and microvessels was not observed (r=0.00, p=0.49). Although the number of MCs was not significantly associated with microvessels, these cells may be related to the growth of odontogenic lesions, particularly RCs. Further studies on the in vivo functions of MCs will make the concept more clear.

Paratracheal air cysts of thoracic inlet in adults: CT findings

International Nuclear Information System (INIS)

Kim, Young Tong; Bae, Won Kyung; Kim, Il Young

2005-01-01

To evaluate the frequency of a paratracheal cyst on CT in an adult, and to compare the degree of loculation and the patient's age with the longest diameter of the air cysts. Of 1520 patients, who underwent a CT scan, 41 patients with paratracheal cysts were enrolled in this study. There were 26-males and 15 females, whose ranged from 24 to 82 years (mean, 59.8). The CT findings were evaluated to determine the relationship between the degree of loculation and the longest diameter of the air cysts. Another tracheal diverticula or an air cyst, as well as the tracheal communication were also evaluated. The longest diameter of the paratracheal air cysts was 1 cm (ρ = 0.043). The paratracheal air cysts 2 cm were multilocular. Four patients had another small tracheal diverticula, and one patient had another small paratracheal air cyst. Tracheal communication was observed in 7 patients (17%). The frequency of paratracheal air cysts in adults undergoing a CT scan was 2.7%. The longest diameter of the paratracheal air cysts was associated with the patient's age. The shape of air cysts became more multilocular as the longest diameter of the paratracheal air cysts increased. Another small tracheal diverticula or air cysts were observed in 12% of patients

Subcortical laminar heterotopia and lissencephaly in two families: a single X linked dominant gene.

Science.gov (United States)

Pinard, J M; Motte, J; Chiron, C; Brian, R; Andermann, E; Dulac, O

1994-01-01

Neuronal migration disorders can now be recognised by MRI. This paper reports two families in which the mothers had subcortical laminar heterotopia and four of their children had either similar heterotopia (two girls) or severe pachygyria or lissencephaly (two boys). Laminar heterotopia was more evident on MRI T2 weighted images. The patients had mild to severe epilepsy and mental retardation depending on the extent of cortical abnormalities. In these families, subcortical laminar heterotopia, pachygyria, and lissencephaly seem to share the same X linked or autosomal dominant gene. No chromosomal abnormalities, especially of chromosome 17, could be identified. For appropriate genetic counselling of the family of a child with lissencephaly or subcortical laminar heterotopia, MRI should be performed in parents or siblings with mental retardation or epilepsy. Images PMID:8057113

Combating Acanthamoeba spp. cysts: what are the options?

OpenAIRE

Anwar, Ayaz; Khan, Naveed Ahmed; Siddiqui, Ruqaiyyah

2018-01-01

Acanthamoeba spp. are protist pathogens and causative agents of serious infections including keratitis and granulomatous amoebic encephalitis. Its ability to convert into dormant and highly resistant cysts form limits effectiveness of available therapeutic agents and presents a pivotal challenge for drug development. During the cyst stage, Acanthamoeba is protected by the presence of hardy cyst walls, comprised primarily of carbohydrates and cyst-specific proteins, hence synthesis inhibition ...

Automated classification of four types of developmental odontogenic cysts.

Science.gov (United States)

Frydenlund, A; Eramian, M; Daley, T

2014-04-01

Odontogenic cysts originate from remnants of the tooth forming epithelium in the jaws and gingiva. There are various kinds of such cysts with different biological behaviours that carry different patient risks and require different treatment plans. Types of odontogenic cysts can be distinguished by the properties of their epithelial layers in H&E stained samples. Herein we detail a set of image features for automatically distinguishing between four types of odontogenic cyst in digital micrographs and evaluate their effectiveness using two statistical classifiers - a support vector machine (SVM) and bagging with logistic regression as the base learner (BLR). Cyst type was correctly predicted from among four classes of odontogenic cysts between 83.8% and 92.3% of the time with an SVM and between 90 ± 0.92% and 95.4 ± 1.94% with a BLR. One particular cyst type was associated with the majority of misclassifications. Omission of this cyst type from the data set improved the classification rate for the remaining three cyst types to 96.2% for both SVM and BLR. Copyright © 2013 Elsevier Ltd. All rights reserved.

Evaluation of mast cells in periapical cysts, dentigerous cysts, and keratocystic odontogenic tumors.

Science.gov (United States)

de Noronha Santos Netto, Juliana; Pires, Fábio Ramôa; da Fonseca, Eliene Carvalho; Silva, Licínio Esmeraldo; de Queiroz Chaves Lourenço, Simone

2012-09-01

Several cell types are associated with the development of cystic and tumoral odontogenic lesions. Among inflammatory cells, mast cells can be associated with their pathogenesis. The aim of this study was to analyze mast cells in periapical cysts, dentigerous cysts, and keratocystic odontogenic tumors. Tissue sections were submitted to toluidine blue staining and immunohistochemistry with antibody anti-tryptase (clone G3). Mast cells were quantitated using Image-Pro Plus software to obtain the mean number of mast cells in three regions: epithelial, superficial portion of the fibrous wall and deep portion of the fibrous wall from 20 periapical cysts, 20 dentigerous cysts (six non-inflamed and 14 inflamed) and 20 keratocystic odontogenic tumors (four non-inflamed and 16 inflamed). The mean number of mast cells detected per lesion by immunohistochemistry (4.1) was higher than by histochemistry (1.5) (Pcysts and keratocystic odontogenic tumors showed a higher mean number of mast cells than non-inflamed lesions in all regions. The deep region from all cysts showed the highest mean number of degranulated mast cells, except for non-inflamed keratocystic odontogenic tumors analyzed by immunohistochemistry. Immunohistochemical staining detected higher number of mast cells than histochemistry. The higher number of mast cells observed in inflamed lesions could indicate the participation of these cells in the inflammatory response in odontogenic lesions. The prevalence of degranulated mast cells in the deep region suggests intense activity of these cells, possibly related to growth of cystic lesions. © 2012 John Wiley & Sons A/S.

Perforated ileal duplication cyst with haemorrhagic pseudocyst formation

International Nuclear Information System (INIS)

Hwang, Im Kyung; Kim, Bong Soo; Kim, Heung Chul; Lee, In Sun; Hwang, Woo Chul; Namkung, Sook

2003-01-01

Duplication cysts of the gastrointestinal tract are rare congenital abnormalities. Ectopic gastric mucosa, which can be found in duplications, may cause peptic ulceration, gastrointestinal bleeding or perforation. We report a 1-year-old boy with a perforated ileal duplication cyst with haemorrhagic pseudocyst formation caused by peptic ulceration of the duplication cyst. It presented a snowman-like appearance consisting of a small, thick-walled, true enteric cyst and a large, thin-walled haemorrhagic pseudocyst on US and CT. It is an unusual manifestation of a duplication cyst, which has not been reported in the English language literature. (orig.)

INTRACORNEAL AND SCLERAL CYST FOLLOWING CATARACT EXTRACTION

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Gabriel van Rij

2002-12-01

Full Text Available Background. A six-year-old boy presented with a large progressive intracorneal and scleral cyst. Two years before, bilateral cataract surgery through a 6.5-mm corneal incision was performed elsewhere.Methods. The posterior wall of the cyst could be excised, as well as the anterior wall in the sclera. Upon histo-pathology the cyst wall was lined by epithelium. The epithelial cells of the anterior side in the cornea were removed with a curette and a corpus alienum drill. Three and a half years after removal of the cyst, there was no recurrence. Visual acuity was 0.8. Conclusions. An intracorneal and scleral inclusion cyst was successfully removed by surgical excision and the removal of epithelial cells by a curette and a corpus alienum drill.

The developing human brain: age-related changes in cortical, subcortical, and cerebellar anatomy.

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Sussman, Dafna; Leung, Rachel C; Chakravarty, M Mallar; Lerch, Jason P; Taylor, Margot J

2016-04-01

This study is the first to characterize normal development and sex differences across neuroanatomical structures in cortical, subcortical, and cerebellar brain regions in a single large cohort. One hundred and ninety-two magnetic resonance images were examined from 96 typically developing females and 96 age-matched typically developing males from 4 to 18 years of age. Image segmentation of the cortex was conducted with CIVET, while that of the cerebellum, hippocampi, thalamus, and basal ganglia were conducted using the MAGeT algorithm. Cortical thickness analysis revealed that most cortical regions decrease linearly, while surface area increases linearly with age. Volume relative to total cerebrum followed a quadratic trend with age, with only the left supramarginal gyrus showing sexual dimorphism. Hippocampal relative volume increased linearly, while the thalamus, caudate, and putamen decreased linearly, and the cerebellum did not change with age. The relative volumes of several subcortical subregions followed inverted U-shaped trends that peaked at ~12 years of age. Many subcortical structures were found to be larger in females than in males, independently of age, while others showed a sex-by-age interaction. This study provides a comprehensive assessment of cortical, subcortical, and cerebellar growth patterns during normal development, and draws attention to the role of sex on neuroanatomical maturation throughout childhood and adolescence.

Dermoid cyst in the mouth floor

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Portelles Masso, Ayelen Maria; Torres Inniguez, Ailin Tamara.

2010-01-01

The Dermoid cyst account for the 0.01 % of all cysts of buccal cavity. Its more frequent location is in the mouth floor. This is the case of a female patient aged 19 who approximately 7 years noted an increase of volume under tongue growing gradually and noting outside face and the discomfort at to speak and to chew. Complementary studies were conducted and under general anesthesia a surgical exeresis was carried out by intrabuccal approach achieving excellent esthetic and functional results. Histopathologic diagnosis matched with a dermoid cyst of mouth floor. Patient has not lesion recurrence after three years after operation. We conclude that the Dermoid cyst of mouth floor appear as benign tumor of middle line. The intrabuccal exeresis demonstrates esthetic and functional benefits. (author)

Bone cysts: unicameral and aneurysmal bone cyst.

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Mascard, E; Gomez-Brouchet, A; Lambot, K

2015-02-01

Simple and aneurysmal bone cysts are benign lytic bone lesions, usually encountered in children and adolescents. Simple bone cyst is a cystic, fluid-filled lesion, which may be unicameral (UBC) or partially separated. UBC can involve all bones, but usually the long bone metaphysis and otherwise primarily the proximal humerus and proximal femur. The classic aneurysmal bone cyst (ABC) is an expansive and hemorrhagic tumor, usually showing characteristic translocation. About 30% of ABCs are secondary, without translocation; they occur in reaction to another, usually benign, bone lesion. ABCs are metaphyseal, excentric, bulging, fluid-filled and multicameral, and may develop in all bones of the skeleton. On MRI, the fluid level is evocative. It is mandatory to distinguish ABC from UBC, as prognosis and treatment are different. UBCs resolve spontaneously between adolescence and adulthood; the main concern is the risk of pathologic fracture. Treatment in non-threatening forms consists in intracystic injection of methylprednisolone. When there is a risk of fracture, especially of the femoral neck, surgery with curettage, filling with bone substitute or graft and osteosynthesis may be required. ABCs are potentially more aggressive, with a risk of bone destruction. Diagnosis must systematically be confirmed by biopsy, identifying soft-tissue parts, as telangiectatic sarcoma can mimic ABC. Intra-lesional sclerotherapy with alcohol is an effective treatment. In spinal ABC and in aggressive lesions with a risk of fracture, surgical treatment should be preferred, possibly after preoperative embolization. The risk of malignant transformation is very low, except in case of radiation therapy. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Mapping abnormal subcortical brain morphometry in an elderly HIV+ cohort.

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Wade, Benjamin S C; Valcour, Victor G; Wendelken-Riegelhaupt, Lauren; Esmaeili-Firidouni, Pardis; Joshi, Shantanu H; Gutman, Boris A; Thompson, Paul M

2015-01-01

Over 50% of HIV + individuals exhibit neurocognitive impairment and subcortical atrophy, but the profile of brain abnormalities associated with HIV is still poorly understood. Using surface-based shape analyses, we mapped the 3D profile of subcortical morphometry in 63 elderly HIV + participants and 31 uninfected controls. The thalamus, caudate, putamen, pallidum, hippocampus, amygdala, brainstem, accumbens, callosum and ventricles were segmented from high-resolution MRIs. To investigate shape-based morphometry, we analyzed the Jacobian determinant (JD) and radial distances (RD) defined on each region's surfaces. We also investigated effects of nadir CD4 + T-cell counts, viral load, time since diagnosis (TSD) and cognition on subcortical morphology. Lastly, we explored whether HIV + participants were distinguishable from unaffected controls in a machine learning context. All shape and volume features were included in a random forest (RF) model. The model was validated with 2-fold cross-validation. Volumes of HIV + participants' bilateral thalamus, left pallidum, left putamen and callosum were significantly reduced while ventricular spaces were enlarged. Significant shape variation was associated with HIV status, TSD and the Wechsler adult intelligence scale. HIV + people had diffuse atrophy, particularly in the caudate, putamen, hippocampus and thalamus. Unexpectedly, extended TSD was associated with increased thickness of the anterior right pallidum. In the classification of HIV + participants vs. controls, our RF model attained an area under the curve of 72%.

Mapping abnormal subcortical brain morphometry in an elderly HIV+ cohort

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Benjamin S.C. Wade

2015-01-01

Full Text Available Over 50% of HIV+ individuals exhibit neurocognitive impairment and subcortical atrophy, but the profile of brain abnormalities associated with HIV is still poorly understood. Using surface-based shape analyses, we mapped the 3D profile of subcortical morphometry in 63 elderly HIV+ participants and 31 uninfected controls. The thalamus, caudate, putamen, pallidum, hippocampus, amygdala, brainstem, accumbens, callosum and ventricles were segmented from high-resolution MRIs. To investigate shape-based morphometry, we analyzed the Jacobian determinant (JD and radial distances (RD defined on each region's surfaces. We also investigated effects of nadir CD4+ T-cell counts, viral load, time since diagnosis (TSD and cognition on subcortical morphology. Lastly, we explored whether HIV+ participants were distinguishable from unaffected controls in a machine learning context. All shape and volume features were included in a random forest (RF model. The model was validated with 2-fold cross-validation. Volumes of HIV+ participants' bilateral thalamus, left pallidum, left putamen and callosum were significantly reduced while ventricular spaces were enlarged. Significant shape variation was associated with HIV status, TSD and the Wechsler adult intelligence scale. HIV+ people had diffuse atrophy, particularly in the caudate, putamen, hippocampus and thalamus. Unexpectedly, extended TSD was associated with increased thickness of the anterior right pallidum. In the classification of HIV+ participants vs. controls, our RF model attained an area under the curve of 72%.

Vocal cysts: clinical, endoscopic, and surgical aspects.

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Martins, Regina Helena Garcia; Santana, Marcela Ferreira; Tavares, Elaine Lara Mendes

2011-01-01

Vocal cysts are benign laryngeal lesions, which affect children and adults. They can be classified as epidermic or mucous-retention cyst. The objective was to study the clinical, endoscopic, and surgical aspects of vocal cysts. We reviewed the medical charts of 72 patients with vocal cysts, considering age, gender, occupation, time of vocal symptoms, nasosinusal and gastroesophageal symptoms, vocal abuse, tabagism, alcoholism, associated lesions, treatment, and histological details. Of the 72 cases, 46 were adults (36 females and 10 male) and 26 were children (eight girls and 18 boys). As far as occupation is concerned, there was a higher incidence of students and teachers. All the patients had symptoms of chronic hoarseness. Nasosinusal (27.77%) and gastroesophageal (32%) symptoms were not relevant. Vocal abuse was reported by 45.83%, smoking by 18%, and alcoholism by 8.4% of the patients. Unilateral cysts were seen in 93% of the cases, 22 patients had associated lesions, such as bridge, sulcus vocalis, and microweb. Surgical treatment was performed in 46 cases. Histological analysis of the epidermic cysts revealed a cavity with caseous content, covered by stratified squamous epithelium, often keratinized. Mucous cysts presented mucous content, and the walls were coated by a cylindrical ciliated epithelium. Vocal cysts are benign vocal fold lesions that affect children and adults, being often associated with vocal overuse, which frequently affects people who use their voices professionally. Vocal symptoms are chronic in course, often times since childhood, and the treatment of choice is surgical removal. A careful examination of the vocal folds is necessary during surgery, because other laryngeal lesions may be associated with vocal cysts. Copyright © 2011 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

Surgical management of anterior chamber epithelial cysts.

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Haller, Julia A; Stark, Walter J; Azab, Amr; Thomsen, Robert W; Gottsch, John D

2003-03-01

To review management strategies for treatment of anterior chamber epithelial cysts. Retrospective review of consecutive interventional case series. Charts of patients treated for epithelial ingrowth over a 10-year period by a single surgeon were reviewed. Cases of anterior chamber epithelial cysts were identified and recorded, including details of ocular history, preoperative and postoperative acuity, intraocular pressure (IOP), and ocular examination, type of surgical intervention, and details of further procedures performed. Seven eyes with epithelial cysts were identified. Patient age ranged from 1.5 to 53 years at presentation. Four patients were children. In four eyes, cysts were secondary to trauma, one case was presumably congenital, one case developed after corneal perforation in an eye with Terrien's marginal degeneration, and one case developed after penetrating keratoplasty (PK). Three eyes were treated with vitrectomy, en bloc resection of the cyst and associated tissue, fluid-air exchange and cryotherapy. The last four eyes were treated with a new conservative strategy of cyst aspiration (three cases) or local excision (one keratin "pearl" cyst), and endolaser photocoagulation of the collapsed cyst wall/base. All epithelial tissue was successfully eradicated by clinical criteria; one case required repeat excision (follow-up, 9 to 78 months, mean 45). Two eyes required later surgery for elevated IOP, two for cataract extraction and one for repeat PK. Final visual acuity ranged from 20/20 to hand motions, depending on associated ocular damage. Best-corrected visual results were obtained in the more conservatively managed eyes. Anterior chamber epithelial cysts can be managed conservatively in selected cases with good results. This strategy may be particularly useful in children's eyes, where preservation of the lens, iris, and other structures may facilitate amblyopia management. Copyright 2003 by Elsevier Science Inc.

Traumatic bone cyst resembling apical periodontitis.

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Rosen, D J; Ardekian, L; Machtei, E E; Peled, M; Manor, R; Laufer, D

1997-10-01

Among the pseudocysts of the jaws, the traumatic bone cyst is known as an asymptomatic lesion often noted unintentionally during routine radiographic examinations. The lesion neither devitalizes the teeth within its borders, nor does it cause resorption of their roots. The well-demarcated traumatic bone cyst often projects into the intraradicular septa and hence has been described as having scalloped borders. The following presentation is of a traumatic bone cyst that resembled periodontal pathology in its appearance.

Transient sexual precocity and ovarian cysts.

OpenAIRE

Lyon, A J; De Bruyn, R; Grant, D B

1985-01-01

Nine girls presenting under the age of 7 years with unsustained sexual precocity are described. Large ovarian cysts were detected by ultrasound in three and laparotomy in one. In two girls the symptoms resolved after surgical removal of the cyst; the other seven had spontaneous remission of symptoms, but in two of these transient breast development and bleeding recurred: further ovarian cyst formation was found in one of these patients. Endocrine studies performed before resolution of the cys...

MR imaging of epithelial cysts of the oral and maxillofacial region

International Nuclear Information System (INIS)

Hisatomi, Miki; Asaumi, Jun-ichi; Konouchi, Hironobu; Shigehara, Hiroshi; Yanagi, Yoshinobu; Kishi, Kanji

2003-01-01

The aim of the present study was to review the magnetic resonance (MR) appearance of primary epithelial cysts in order to distinguish the cysts from other possible lesions. MR images were obtained in 27 cases of epithelial cysts, including 7 odontogenic keratocysts, 3 dentigerous cysts, 1 glandular odontogenic cyst, 10 radicular cysts, 4 nasopalatine duct cysts, and 2 nasolabial cysts. In addition, contrast enhanced MR imagings were performed in 12 cases, including 3 odontogenic keratocysts, 1 dentigerous cyst, 1 glandular odontogenic cyst, and 7 radicular cysts. We obtained the following results on the basis of the above MR and contrast enhanced MR findings. (a) Odontogenic keratocysts had a predilection for intermediate-high signal intensity (SI) on T1-weighted images (WI) and heterogeneous low-high SI on T2WI. (b) Dentigerous cysts, glandular odontogenic cyst, radicular cysts and nasolabial cysts showed the same predilection with the SI, which were homogeneous intermediate SI on T1WI and homogeneous high SI on T2WI. (c) The MR images of the nasopalatine duct cysts, which showed homogeneous high SI on T1WI, were specific. (d) The Gd-T1WI would be useful in decisively differentiating odontogenic cysts, which showed rim-enhancement, from tumors consisting of solid components. In conclusion, we were able to obtain more information from the MR and contrast enhanced MR images than from conventional radiograph findings

Species of Heterodera cysts in cereal fields in Flanders.

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Yilmaz, Zeliha Colak; Deeren, Anne-Marie; De Sutter, Nancy; Viaene, Nicole

2009-01-01

Heterodera is a genus of cyst-forming nematodes, including the cereal cysts which can provoke yield reductions in grain crops. As little is known about the occurrence of these cysts in Belgian grain fields, a survey was organized, starting in Flanders. Soil samples were taken from 50 fields where cereals are grown in rotation with mainly beet, potato and vegetables. Cysts were extracted from the 112 samples and 10 individuals per sample were identified up to species level by morphometrical and morphological observations. The beet cyst nematode, Heterodera schachtii, was found in 34 fields (56%) at infestation levels varying from 0.6 to 1322 cysts/kg soil. Other Heterodera species (e.g. H. trifolii, H. mani) were found in low numbers and sometimes in mixtures with H. schachtii, but no cereal cysts were detected. This survey confirms that beet cyst nematodes are a problem in Flanders. The few cereal cysts that might be present were perhaps not detected due to the few individuals that were identified. For this reason, molecular identification tools which allow fast and accurate identification of Heterodera species would be very useful. It could be interesting to find out why cereal cysts are suppressed in our regions and to expand the survey to the Walloon region where more cereals are grown.

Spinal extradural arachnoid cysts

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Abolfazl Rahimizadeh

2013-01-01

Full Text Available OBJECTIVE: Extradural arachnoid cysts (EACs are rare causes of spinal cord compression and cauda equina. These benign lesions appear in the literature mainly as single case reports. In this article, we present the largest series found in literature, with four new cases of spinal extradural arachnoid cysts. The characteristic imaging features, details of surgical steps and strategies to prevent postoperative kyphosis in this cystic pathology will be discussed.

Surgical treatment for hypopharyngeal cysts with a side-opened direct laryngoscope.

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Kawaida, M; Fukuda, H; Shiotani, A; Kohno, N

1994-01-01

Two cases of hypopharyngeal cyst are reported. Both cysts occurred in the piriform sinus of the hypopharynx. Histopathological examination indicated that both were retention cysts. These cysts were removed by laryngomicrosurgical technique using a side-opened direct laryngoscope. In the cyst with a distinct base, a laryngomicrosurgical snare was used for removal. In the wide-based cyst, the mucous membrane around the cyst was incised with an electrosurgical instrument and then detached to facilitate removal. In this paper, we describe our surgical procedure for removing hypopharyngeal cysts and discuss the causes of such cysts.

Orbital dermoid and epidermoid cysts: Case study

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Veselinović Dragan

2010-01-01

Full Text Available Introduction. Dermoid and epidermoid cysts of the orbit belong to choristomas, tumours that originate from the aberrant primordial tissue. Clinically, they manifest as cystic movable formations mostly localized in the upper temporal quadrant of the orbit. They are described as both superficial and deep formations with most frequently slow intermittent growth. Apart from aesthetic effects, during their growth, dermoid and epidermoid cysts can cause disturbances in the eye motility, and in rare cases, also an optical nerve compression syndrome. Case Outline. In this paper, we described a child with a congenital orbital dermoid cyst localized in the upper-nasal quadrant that was showing signs of a gradual enlargement and progression. The computerized tomography revealed a cyst of 1.5-2.0 cm in size. At the Maxillofacial Surgery Hospital in Niš, the dermoid cyst was extirpated in toto after orbitotomy performed by superciliary approach. Postoperative course was uneventful, without inflammation signs, and after two weeks excellent functional and aesthetic effects were achieved. Conclusion. Before the decision to treat the dermoid and epidermoid cysts operatively, a detailed diagnostic procedure was necessary to be done in order to locate the cyst precisely and determine its size and possible propagation into the surrounding periorbital structures. Apart from cosmetic indications, operative procedures are recommended in the case of cysts with constant progressions, which cause the pressure to the eye lobe, lead to motility disturbances and indirectly compress the optical nerve and branches of the cranial nerves III, IV and VI.

Fractal Dimension Analysis of Subcortical Gray Matter Structures in Schizophrenia.

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Guihu Zhao

Full Text Available A failure of adaptive inference-misinterpreting available sensory information for appropriate perception and action-is at the heart of clinical manifestations of schizophrenia, implicating key subcortical structures in the brain including the hippocampus. We used high-resolution, three-dimensional (3D fractal geometry analysis to study subtle and potentially biologically relevant structural alterations (in the geometry of protrusions, gyri and indentations, sulci in subcortical gray matter (GM in patients with schizophrenia relative to healthy individuals. In particular, we focus on utilizing Fractal Dimension (FD, a compact shape descriptor that can be computed using inputs with irregular (i.e., not necessarily smooth surfaces in order to quantify complexity (of geometrical properties and configurations of structures across spatial scales of subcortical GM in this disorder. Probabilistic (entropy-based information FD was computed based on the box-counting approach for each of the seven subcortical structures, bilaterally, as well as the brainstem from high-resolution magnetic resonance (MR images in chronic patients with schizophrenia (n = 19 and age-matched healthy controls (n = 19 (age ranges: patients, 22.7-54.3 and healthy controls, 24.9-51.6 years old. We found a significant reduction of FD in the left hippocampus (median: 2.1460, range: 2.07-2.18 vs. median: 2.1730, range: 2.15-2.23, p<0.001; Cohen's effect size, U3 = 0.8158 (95% Confidence Intervals, CIs: 0.6316, 1.0, the right hippocampus (median: 2.1430, range: 2.05-2.19 vs. median: 2.1760, range: 2.12-2.21, p = 0.004; U3 = 0.8421 (CIs: 0.5263, 1, as well as left thalamus (median: 2.4230, range: 2.40-2.44, p = 0.005; U3 = 0.7895 (CIs: 0.5789, 0.9473 in schizophrenia patients, relative to healthy individuals. Our findings provide in-vivo quantitative evidence for reduced surface complexity of hippocampus, with reduced FD indicating a less complex, less regular GM surface detected in

Supratentorial endodermal cysts: review of literature and case report.

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Caruso, Riccardo; Artico, Marco; Colonnese, Claudio; Marrocco, Luigi; Wierzbicki, Venceslao

2013-11-01

Supratentorial endodermal cysts are very rare pathological entities. Their pathoembryology is largely unknown and they can represent a diagnostic challenge. A research performed on the PubMed database in December 2010, to screen for supratentorial endodermal cyst studies, demonstrated that since 1960 only 31 supratentorial endodermal cysts have been described in the literature, including our case: a 42-year-old woman with a parasellar endodermal cyst. These lesions are usually benign. As with other types of brain cysts, the signs and symptoms caused by supratentorial endodermal cysts are mainly linked to the compression or irritation of surrounding neural structures. Upon neuroimaging examination, they typically appear as a round or lobulated mass. The signal intensity may vary depending on the protein content of the cyst. The majority of reported supratentorial endodermal cysts were completely excised with good or excellent results. Incomplete excision can result in an increased risk of recurrence, infection, and dissemination. Georg Thieme Verlag KG Stuttgart · New York.

Supratentorial arachnoid cyst and associated subdural hematoma: neuroradiologic studies

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Ochi, M. [Dept. of Radiology, Nagasaki Univ. School of Medicine, (Japan); Morikawa, M. [Dept. of Radiology, Nagasaki Univ. School of Medicine, (Japan)]|[Dept. of Radiology, National Nagasaki Chuo Hospital, Ohmura (Japan); Ogino, A. [Dept. of Radiology, Nagasaki Univ. School of Medicine, (Japan); Nagaoki, K. [Dept. of Radiology, Nagasaki Univ. School of Medicine, (Japan)]|[Dept. of Radiology, Isahaya General Hospital (Japan); Hayashi, K. [Dept. of Radiology, Nagasaki Univ. School of Medicine, (Japan)

1996-10-01

CT and MR images of 8 patients with supratentorial arachnoid cyst complicated by subdural hematoma were studied and compared with those of 8 patients who developed nontraumatic subdural hematoma without arachnoid cyst. Ot the 8 patients with supratentorial arachnoid cyst, CT and MR disclosed temporal bulging and/or thinning of the temporal squama in all 6 patients with middle fossa arachnoid cysts, and the thinning of the calvaria was evident in another patient with a convexity cyst. Calvarial thinning at the site corresponding to interhemispheric arachnoid cyst was clearly depicted on coronal MR images. In contrast, none of the 8 young patients with nontraumatic subdural hematoma without arachnoid cyst had abnormal calvaria. Temporal bulging and thinning of the overlying calvaria were identified as diagnostic CT and MR features of arachnoid cyst with complicating intracystic and subdural hermorrhage. Radiologists should be aware of this association and should evaluate the bony structure carefully. (orig.)

[Giant intradiploic infratentorial epidermoid cyst].

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Alberione, F; Caire, F; Fischer-Lokou, D; Gueye, M; Moreau, J J

2007-10-01

Epidermoid cysts are benign, uncommon lesions (1% of all intracranial tumors). Their localization is intradiploic in 25% of cases, and exceptionally subtentorial. We report here a rare case of giant intradiploic infratentorial epidermoid cyst. A 74-year old patient presented with recent diplopia and sindrome cerebellar. CT scan and MR imaging revealed a giant osteolytic extradural lesion of the posterior fossa (5.2 cm x 3.8 cm) with a small area of peripheral enhancement after contrast injection. Retrosigmoid suboccipital craniectomy allowed a satisfactory removal of the tumor, followed by an acrylic cranioplasty. The outcome was good. Neuropathological examination confirmed an epidermoid cyst. We review the literature and discuss our case.

Measurement and genetics of human subcortical and hippocampal asymmetries in large datasets.

Science.gov (United States)

Guadalupe, Tulio; Zwiers, Marcel P; Teumer, Alexander; Wittfeld, Katharina; Vasquez, Alejandro Arias; Hoogman, Martine; Hagoort, Peter; Fernandez, Guillen; Buitelaar, Jan; Hegenscheid, Katrin; Völzke, Henry; Franke, Barbara; Fisher, Simon E; Grabe, Hans J; Francks, Clyde

2014-07-01

Functional and anatomical asymmetries are prevalent features of the human brain, linked to gender, handedness, and cognition. However, little is known about the neurodevelopmental processes involved. In zebrafish, asymmetries arise in the diencephalon before extending within the central nervous system. We aimed to identify genes involved in the development of subtle, left-right volumetric asymmetries of human subcortical structures using large datasets. We first tested the feasibility of measuring left-right volume differences in such large-scale samples, as assessed by two automated methods of subcortical segmentation (FSL|FIRST and FreeSurfer), using data from 235 subjects who had undergone MRI twice. We tested the agreement between the first and second scan, and the agreement between the segmentation methods, for measures of bilateral volumes of six subcortical structures and the hippocampus, and their volumetric asymmetries. We also tested whether there were biases introduced by left-right differences in the regional atlases used by the methods, by analyzing left-right flipped images. While many bilateral volumes were measured well (scan-rescan r = 0.6-0.8), most asymmetries, with the exception of the caudate nucleus, showed lower repeatabilites. We meta-analyzed genome-wide association scan results for caudate nucleus asymmetry in a combined sample of 3,028 adult subjects but did not detect associations at genome-wide significance (P left-right patterning of the viscera. Our results provide important information for researchers who are currently aiming to carry out large-scale genome-wide studies of subcortical and hippocampal volumes, and their asymmetries. Copyright © 2013 Wiley Periodicals, Inc.

Tailgut cyst in a child

International Nuclear Information System (INIS)

Podberesky, Daniel J.; Emery, Kathleen H.; Care, Marguerite M.; Anton, Christopher G.; Falcone, Richard A.; Ryckman, Frederick C.; Miles, Lili

2005-01-01

Tailgut cyst, or retrorectal cystic hamartoma, is a rare congenital lesion found in the presacral space. The lesion has been infrequently reported in the literature. We report the MRI findings of a tailgut cyst in a 2-year-old girl who presented with a sacral dimple and skin discoloration. (orig.)

Percutaneous drainage without sclerotherapy for benign ovarian cysts.

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Zerem, Enver; Imamović, Goran; Omerović, Safet

2009-07-01

To evaluate percutaneous short-term catheter drainage in the management of benign ovarian cysts in patients at increased surgical risk. Thirty-eight patients with simple ovarian cysts were treated with drainage of fluid content by catheters until output stopped. All patients were poor candidates for surgery. All procedures were performed under ultrasonographic (US) control and local anesthesia. Cytologic examination was performed in all cases. The patients were followed up monthly with color Doppler US for 12 months. Outcome measure was the recurrence of a cyst. During the 12-month follow-up period, 10 of 38 cysts recurred. Seven of the 10 cysts required further intervention, and three were followed up without intervention. Four of the seven patients who required further intervention underwent repeat transabdominal aspiration and three declined repeat aspiration and subsequently underwent surgery. After repeated aspirations, two of four cysts disappeared, one necessitated follow-up only, and one necessitated surgical intervention. Cyst volume (P = .009) and diameter (P = .001) were significantly larger in the cysts that recurred. No evidence of malignancy was reported in the cytologic examination in any patient. No patients developed malignancy during follow-up. No major complications were observed. The hospital stay was 1 day for all patients. The median duration of drainage in the groups with resolved and recurrent cysts was 1 day (interquartile range, 1-1) and 2 days (interquartile range, 1-3), respectively (P = .04). In patients considered poor candidates for open surgery or laparoscopy, percutaneous treatment of ovarian cysts with short-term catheter drainage without sclerotherapy appears to be a safe and effective alternative, with low recurrence rates.

Laryngeal Cysts in Adults: Simplifying Classification and Management.

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Heyes, Richard; Lott, David G

2017-12-01

Objective Laryngeal cysts may occur at any mucosa-lined location within the larynx and account for 5% to 10% of nonmalignant laryngeal lesions. A number of proposed classifications for laryngeal cysts exist; however, no previously published classification aims to guide management. This review analyzes contemporary laryngeal cyst management and proposes a framework for the terminology and management of cystic lesions in the larynx. Data Sources PubMed/Medline. Review Methods A primary literature search of the entire Medline database was performed for all titles of publications pertaining to laryngeal cysts and reviewed for relevance. Full manuscripts were reviewed per the relevance of their titles and abstracts, and selection into this review was according to their clinical and scientific relevance. Conclusion Laryngeal cysts have been associated with rapid-onset epiglottitis, dyspnea, stridor, and death; therefore, they should not be considered of little significance. Symptoms are varied and nonspecific. Laryngoscopy is the primary initial diagnostic tool. Cross-sectional imaging may be required, and future use of endolaryngeal ultrasound and optical coherence tomography may revolutionize practice. Where possible, cysts should be completely excised, and there is growing evidence that a transoral approach is superior to transcervical excision for nearly all cysts. Histology provides definitive diagnosis, and oncocytic cysts require close follow-up. Implications for Practice A new classification system is proposed that increases clarity in terminology, with the aim of better preparing surgeons and authors for future advances in the understanding and management of laryngeal cysts.

White matter cysts in patients with tuberous sclerosis

International Nuclear Information System (INIS)

Marti-Bonmati, L.; Dosda, R.; Menor, F.; Arana, E.; Poyatos, C.

1999-01-01

The presence of cysts in the white matter of the central nervous system of patients with tuberous sclerosis (TS) is an uncommon finding that has been reported only recently in neuroimaging studies. This article assesses the prevalence of these lesions in a large series of patients studied by magnetic resonance imaging (MRI) and their relationship to other epidemiological and imaging findings. MRI studies were performed in 46 patients (23 males and 23 females) with a mean age of 12.7 years, and the results were examined retrospectively in the search for cortical tubers, subependymal nodules and white matter nodules, lines and cysts. Nine patients (19.6%) presented cysts in white matter. Seven had only one cyst and the remaining two patients each had two. Multiple regression analysis relating the presence of the cysts with other neuroimaging findings in these patients revealed a statistically significant relationship only with white matter nodules (odds ratio: 7.5; p=0.006). White matter cysts are small, supratentorial lesions of deep location. There is a statistically relationship between the presence of these cysts and that of nodular lesions in the white matter. This finding supports the theory that the cyst originate from white matter nodules. (Author) 17 refs

Hearing it again and again: on-line subcortical plasticity in humans.

Science.gov (United States)

Skoe, Erika; Kraus, Nina

2010-10-26

Human brainstem activity is sensitive to local sound statistics, as reflected in an enhanced response in repetitive compared to pseudo-random stimulus conditions [1]. Here we probed the short-term time course of this enhancement using a paradigm that assessed how the local sound statistics (i.e., repetition within a five-note melody) interact with more global statistics (i.e., repetition of the melody). To test the hypothesis that subcortical repetition enhancement builds over time, we recorded auditory brainstem responses in young adults to a five-note melody containing a repeated note, and monitored how the response changed over the course of 1.5 hrs. By comparing response amplitudes over time, we found a robust time-dependent enhancement to the locally repeating note that was superimposed on a weaker enhancement of the globally repeating pattern. We provide the first demonstration of on-line subcortical plasticity in humans. This complements previous findings that experience-dependent subcortical plasticity can occur on a number of time scales, including life-long experiences with music and language, and short-term auditory training. Our results suggest that the incoming stimulus stream is constantly being monitored, even when the stimulus is physically invariant and attention is directed elsewhere, to augment the neural response to the most statistically salient features of the ongoing stimulus stream. These real-time transformations, which may subserve humans' strong disposition for grouping auditory objects, likely reflect a mix of local processes and corticofugal modulation arising from statistical regularities and the influences of expectation. Our results contribute to our understanding of the biological basis of statistical learning and initiate a new investigational approach relating to the time-course of subcortical plasticity. Although the reported time-dependent enhancements are believed to reflect universal neurophysiological processes, future

Hearing it again and again: on-line subcortical plasticity in humans.

Directory of Open Access Journals (Sweden)

Erika Skoe

2010-10-01

Full Text Available Human brainstem activity is sensitive to local sound statistics, as reflected in an enhanced response in repetitive compared to pseudo-random stimulus conditions [1]. Here we probed the short-term time course of this enhancement using a paradigm that assessed how the local sound statistics (i.e., repetition within a five-note melody interact with more global statistics (i.e., repetition of the melody.To test the hypothesis that subcortical repetition enhancement builds over time, we recorded auditory brainstem responses in young adults to a five-note melody containing a repeated note, and monitored how the response changed over the course of 1.5 hrs. By comparing response amplitudes over time, we found a robust time-dependent enhancement to the locally repeating note that was superimposed on a weaker enhancement of the globally repeating pattern.We provide the first demonstration of on-line subcortical plasticity in humans. This complements previous findings that experience-dependent subcortical plasticity can occur on a number of time scales, including life-long experiences with music and language, and short-term auditory training. Our results suggest that the incoming stimulus stream is constantly being monitored, even when the stimulus is physically invariant and attention is directed elsewhere, to augment the neural response to the most statistically salient features of the ongoing stimulus stream. These real-time transformations, which may subserve humans' strong disposition for grouping auditory objects, likely reflect a mix of local processes and corticofugal modulation arising from statistical regularities and the influences of expectation. Our results contribute to our understanding of the biological basis of statistical learning and initiate a new investigational approach relating to the time-course of subcortical plasticity. Although the reported time-dependent enhancements are believed to reflect universal neurophysiological

Unusual Clinicoradiographic Presentation of a Lateral Periodontal Cyst

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H. T. Kumuda Arvind Rao

2012-01-01

Full Text Available The lateral periodontal cyst is an uncommon, but well-recognized type of developmental odontogenic cyst. Lateral periodontal cysts are defined as non-keratinized and non-inflammatory developmental cysts located adjacent or lateral to the root of a vital tooth. It is a relatively uncommon lesion found mostly in adults (5th to 7th decades and it is rare in young people under 30 years of age. A common site of occurrence is the mandibular premolar region. It does not have a predilection for any race or sex. Histopathologically, the lateral periodontal cyst lining is characterized by a thin cuboidal to stratified squamous non-keratinizing epithelium, ranging from one to five cell layers and presence of one or more epithelial thickenings or plaques.The purpose of this article is to report a case of interradicular radiolucent cystic lesion in a thirteen-year-old girl, located in a rare site of the maxillary premolar area, mimicking clinical and radiographical features of a residual cyst, but histopathologically proven to be a lateral periodontal cyst.

Spontaneous haemorrhage and rupture of third ventricular colloid cyst.

LENUS (Irish Health Repository)

Ogbodo, Elisha

2012-01-01

Acute bleeding within a colloid cyst of the third ventricle represents a rare event causing sudden increase in the cyst volume that may lead to acute hydrocephalus and rapid neurological deterioration. We report a case of spontaneous rupture of haemorrhagic third ventricular colloid cyst and its management. A 77-year-old ex-smoker presented with unsteady gait, incontinence and gradually worsening confusion over a 3-week period. Brain CT scan findings were highly suggestive of a third ventricular colloid cyst with intraventricular rupture. He underwent cyst excision and histopathology, which confirmed the radiological diagnosis with evidence of haemorrhage within the cyst. A ventriculo peritoneal shunt was performed for delayed hydrocephalus. Surgical management of these patients must include emergency ventriculostomy followed by prompt surgical removal of the haemorrhagic cyst.

Unusual long-term complications of a splenic cyst.

LENUS (Irish Health Repository)

Ward, E V M

2012-02-01

Splenic cysts are relatively uncommon, and are usually asymptomatic. They are benign, typically treated conservatively and followed up with ultrasound examination, with few reported complications. We report a case of a simple splenic cyst that was followed up on imaging over a seven-year period. During that time, the cyst gradually enlarged from 5 cm to 12 cm in diameter, however the patient remained asymptomatic. After seven years, the patient was admitted with abdominal pain and a pelvic mass. The spleen was located within the pelvis, which was felt to be due to the weight of the cyst which caused the spleen to migrate out of its normal position. This case illustrates an extremely unusual complication, and suggests that while most splenic cysts may be managed conservatively, enlarging cysts may be prone to gravitational effects and prophylactic treatment should be considered.

Unusual long-term complications of a splenic cyst.

LENUS (Irish Health Repository)

Ward, E V M

2010-01-01

Splenic cysts are relatively uncommon, and are usually asymptomatic. They are benign, typically treated conservatively and followed up with ultrasound examination, with few reported complications. We report a case of a simple splenic cyst that was followed up on imaging over a seven-year period. During that time, the cyst gradually enlarged from 5 cm to 12 cm in diameter, however the patient remained asymptomatic. After seven years, the patient was admitted with abdominal pain and a pelvic mass. The spleen was located within the pelvis, which was felt to be due to the weight of the cyst which caused the spleen to migrate out of its normal position. This case illustrates an extremely unusual complication, and suggests that while most splenic cysts may be managed conservatively, enlarging cysts may be prone to gravitational effects and prophylactic treatment should be considered.

Peripheral Presentation of Periapical Cyst: A Rare Finding

OpenAIRE

Nilesh Kumar; Sameer A Zope; Mohan S Sannale

2015-01-01

Periapical cyst is a slow growing dental cyst, which is discove­ red on routine intraoral radiograph or cause localized intra­ osseous jaw swelling. It is typically found at root apex of the involved tooth and is discovered on routine radiography. This paper reports a rare presentation of periapical cyst. The cyst was localized in the premaxillary subcutaneous tissue, causing diagnostic difficulty. The steps in diagnosis of the lesion are also discussed

Isolated Retroperitoneal Hydatid Cyst Invading Splenic Hilum

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Safak Ozturk

2014-01-01

Full Text Available Introduction. Hydatid disease (HD is an infestation that is caused by the larval stage of Echinococcus granulosus. The liver is affected in approximately two-thirds of patients, the lungs in 25%, and other organs in a small proportion. Primary retroperitoneal hydatid cyst is extremely rare. The most common complaint is abdominal pain; however, the clinical features of HD may be generally dependent on the location of the cyst. Case Presentation. A 43-year-old female was admitted with the complaint of abdominal pain. Her physical examination was normal. Computed tomography (CT revealed a 17 × 11 cm cystic lesion, with a thick and smooth wall that is located among the left liver lobe, diaphragm, spleen, tail of the pancreas, and transverse colon and invading the splenic hilum. Total cystectomy and splenectomy were performed. Pathological examination was reported as cyst hydatid. Discussion. Cysts in the peritoneal cavity are mainly the result of the spontaneous or traumatic rupture of concomitant hepatic cysts or surgical inoculation of a hepatic cyst. Serological tests contribute to diagnosis. In symptomatic and large hydatid peritoneal cysts, surgical resection is the only curative treatment. Total cystectomy is the gold standard. Albendazole or praziquantel is indicated for inoperable and disseminated cases. Percutaneous aspiration, injection, and reaspiration (PAIR technique is another nonsurgical option.

A retrospective study of oral cysts in Nigerian children.

Science.gov (United States)

Salako, N O; Taiwo, E O

1995-01-01

A retrospective analysis of oral cysts that were seen over an 11-year period in children at a dental institution in Nigeria was carried out. In general, oral cysts accounted for only 2.6% of the total biopsied lesions during the period under review. The most common oral cysts were the mucous retention cysts, the gingival cysts of infants and the dentigerous cyst. The commonest sites were the maxilla, the mandible and the floor of the mouth respectively and there was no significant difference in sex preference. Most of the cases were seen in the age group 11-16 years while the least was in the group aged 6-10 years.

SU-E-P-36: Evaluation of MLC Positioning Errors in Dynamic IMRT Treatments by Analyzing Dynalog Files

International Nuclear Information System (INIS)

Olasolo, J; Pellejero, S; Gracia, M; Gallardo, N; Martin, M; Lozares, S; Maneru, F; Bragado, L; Miquelez, S; Rubio, A

2015-01-01

Purpose: To assess the accuracy of MLC positioning in Varian linear accelerator, in dynamic IMRT technique, from the analysis of dynalog files generated by the MLC controller. Methods: In Clinac accelerators (pre-TrueBeam technology), control system has an approximately 50ms delay (one control cycle time). Then, the system compares the measured position to the planned position corresponding to the next control cycle. As it has been confirmed by Varian technical support, this effect causes that measured positions appear in dynalogs one cycle out of phase with respect to the planned positions. Around 9000 dynalogs have been analyzed, coming from the three linear accelerators of our center (one Trilogy and two Clinac 21EX) equipped with a Millennium 120 MLC. In order to compare our results to recent publications, leaf positioning errors (RMS and 95th percentile) are calculated with and without delay effect. Dynalogs have been analyzed using a in-house Matlab software. Results: The RMS errors were 0.341, 0.339 and 0.348mm for each Linac; being the average error 0.343 mm. The 95th percentiles of the error were 0.617, 0.607 and 0.625; with an average of 0.617mm. A recent multi-institution study carried out by Kerns et al. found a mean leaf RMS error of 0.32mm and a 95th percentile error value of 0.64mm.Without delay effect, mean leaf RMS errors obtained were 0.040, 0.042 and 0.038mm for each treatment machine; being the average 0.040mm. The 95th percentile error values obtained were 0.057, 0.058 and 0.054 mm, with an average of 0.056mm. Conclusion: Results obtained for the mean leaf RMS error and the mean 95th percentile were consistent with the multi-institution study. Calculated error statistics with delay effect are significantly larger due to the speed proportional and systematic leaf offset. Consequently it is proposed to correct this effect in dynalogs analysis to determine the MLC performance

Serial tomotherapy vs. MLC-IMRT (Multileaf Collimator Intensity Modulated Radiotherapy) for simultaneous boost treatment large intracerebral lesions

International Nuclear Information System (INIS)

Wolff, Dirk; Lohr, Frank; Mai, Sabine; Polednik, Martin; Wenz, Frederik; Dobler, Barbara

2009-01-01

Introduction: Recent data suggest that a radiosurgery boost treatment for up to three brain metastases in addition to whole brain radiotherapy (WBRT) is beneficial. Sequential treatment of multiple metastatic lesions is time-consuming and optimal normal tissue sparing is not trivial for larger metastases when separate plans are created and are only superimposed afterwards. Sequential Tomotherapy with noncoplanar arcs and Multi-field IMRT may streamline the process and enable easy simultaneous treatment. We compared plans for 2-3 intracerebral targets calculated with Intensity Modulated Radiotherapy (IMRT) based on treatment with MLC or sequential Tomotherapy using the Peacock-System. Treatment time was not to exceed 90 min on a linac with standart dose rate. MIMiC plans without treatment-time restrictions were created as a benchmark. Materials and methods: Calculations are based on a Siemens KD2 linac with a dose rate of 200 MU/min. Step-and-Shoot IMRT is performed with a standard MLC (2 x 29 leaves, 1 cm), serial Tomotherapy with the Multivane-Collimator MIMiC (NOMOS Inc. USA). Treatment plans are created with Corvus 5.0. To create plans with good conformity we chose a noncoplanar beam- and arc geometry for each approach (IMRT 4-, MIMiC 5-couch angles). The benchmark MIMiC plans with maximally steep dose gradients had 9 couch angles. For plan comparison reasons, 10Gy were prescribed to 90% of the PTV. Steepness of dose gradients, homogeneity and conformity were assessed by the following parameters: Volume encompassed by certain isodoses outside the target as well as homogeneity and conformity as indicated by Homogeneity- and Conformity-Index. Results: Plans without treatment-time restrictions had slightest dose to organ at risk (OAR), normal tissue and least Conformity-index. MIMiC- and MLC-IMRT based plans can be treated within the intended period of 90 min, all plans met the required dose. MLC based plans resulted in higher dose to organs at risk (OAR) and dose

Determination of the optimal tolerance for MLC positioning in sliding window and VMAT techniques

International Nuclear Information System (INIS)

Hernandez, V.; Abella, R.; Calvo, J. F.; Jurado-Bruggemann, D.; Sancho, I.; Carrasco, P.

2015-01-01

Purpose: Several authors have recommended a 2 mm tolerance for multileaf collimator (MLC) positioning in sliding window treatments. In volumetric modulated arc therapy (VMAT) treatments, however, the optimal tolerance for MLC positioning remains unknown. In this paper, the authors present the results of a multicenter study to determine the optimal tolerance for both techniques. Methods: The procedure used is based on dynalog file analysis. The study was carried out using seven Varian linear accelerators from five different centers. Dynalogs were collected from over 100 000 clinical treatments and in-house software was used to compute the number of tolerance faults as a function of the user-defined tolerance. Thus, the optimal value for this tolerance, defined as the lowest achievable value, was investigated. Results: Dynalog files accurately predict the number of tolerance faults as a function of the tolerance value, especially for low fault incidences. All MLCs behaved similarly and the Millennium120 and the HD120 models yielded comparable results. In sliding window techniques, the number of beams with an incidence of hold-offs >1% rapidly decreases for a tolerance of 1.5 mm. In VMAT techniques, the number of tolerance faults sharply drops for tolerances around 2 mm. For a tolerance of 2.5 mm, less than 0.1% of the VMAT arcs presented tolerance faults. Conclusions: Dynalog analysis provides a feasible method for investigating the optimal tolerance for MLC positioning in dynamic fields. In sliding window treatments, the tolerance of 2 mm was found to be adequate, although it can be reduced to 1.5 mm. In VMAT treatments, the typically used 5 mm tolerance is excessively high. Instead, a tolerance of 2.5 mm is recommended

SU-F-T-465: Two Years of Radiotherapy Treatments Analyzed Through MLC Log Files

Energy Technology Data Exchange (ETDEWEB)

Defoor, D [University of Texas HSC SA, New Braunfles, TX (United States); Kabat, C; Papanikolaou, N [University of Texas HSC SA, San Antonio, TX (United States); Stathakis, S [Cancer Therapy and Research Center, San Antonio, TX (United States)

2016-06-15

Purpose: To present treatment statistics of a Varian Novalis Tx using more than 90,000 Varian Dynalog files collected over the past 2 years. Methods: Varian Dynalog files are recorded for every patient treated on our Varian Novalis Tx. The files are collected and analyzed daily to check interfraction agreement of treatment deliveries. This is accomplished by creating fluence maps from the data contained in the Dynalog files. From the Dynalog files we have also compiled statistics for treatment delivery times, MLC errors, gantry errors and collimator errors. Results: The mean treatment time for VMAT patients was 153 ± 86 seconds while the mean treatment time for step & shoot was 256 ± 149 seconds. Patient’s treatment times showed a variation of 0.4% over there treatment course for VMAT and 0.5% for step & shoot. The average field sizes were 40 cm2 and 26 cm2 for VMAT and step & shoot respectively. VMAT beams contained and average overall leaf travel of 34.17 meters and step & shoot beams averaged less than half of that at 15.93 meters. When comparing planned and delivered fluence maps generated using the Dynalog files VMAT plans showed an average gamma passing percentage of 99.85 ± 0.47. Step & shoot plans showed an average gamma passing percentage of 97.04 ± 0.04. 5.3% of beams contained an MLC error greater than 1 mm and 2.4% had an error greater than 2mm. The mean gantry speed for VMAT plans was 1.01 degrees/s with a maximum of 6.5 degrees/s. Conclusion: Varian Dynalog files are useful for monitoring machine performance treatment parameters. The Dynalog files have shown that the performance of the Novalis Tx is consistent over the course of a patients treatment with only slight variations in patient treatment times and a low rate of MLC errors.

Bilingualism at the core of the brain. Structural differences between bilinguals and monolinguals revealed by subcortical shape analysis.

Science.gov (United States)

Burgaleta, Miguel; Sanjuán, Ana; Ventura-Campos, Noelia; Sebastian-Galles, Núria; Ávila, César

2016-01-15

Naturally acquiring a language shapes the human brain through a long-lasting learning and practice process. This is supported by previous studies showing that managing more than one language from early childhood has an impact on brain structure and function. However, to what extent bilingual individuals present neuroanatomical peculiarities at the subcortical level with respect to monolinguals is yet not well understood, despite the key role of subcortical gray matter for a number of language functions, including monitoring of speech production and language control - two processes especially solicited by bilinguals. Here we addressed this issue by performing a subcortical surface-based analysis in a sample of monolinguals and simultaneous bilinguals (N=88) that only differed in their language experience from birth. This analysis allowed us to study with great anatomical precision the potential differences in morphology of key subcortical structures, namely, the caudate, accumbens, putamen, globus pallidus and thalamus. Vertexwise analyses revealed significantly expanded subcortical structures for bilinguals compared to monolinguals, localized in bilateral putamen and thalamus, as well as in the left globus pallidus and right caudate nucleus. A topographical interpretation of our results suggests that a more complex phonological system in bilinguals may lead to a greater development of a subcortical brain network involved in monitoring articulatory processes. Copyright © 2015 Elsevier Inc. All rights reserved.

Organization of the cysts in bee (Hymenoptera, Apidae testis: number of spermatozoa per cyst

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Cruz-Landim Carminda da

2001-01-01

Full Text Available The morphology of the cyst cells in Apis mellifera Linné, 1758, Scaptotrigona postica Latreille, 1804, and Melipona bicolor bicolor Lepeletier, 1836 testis, as well as the average number of spermatic cells are reported. The data indicates a supporting and nourrishing role of the cyst cells to the developing cystocytes. The counts of immature spermatozoa in the cysts show an average of 202.8 ± 21.2 spermatozoa for A. mellifera, 117.4 ± 8.68 for S. postica and 88.8 ± 15.57 for M. bicolor, which predict the occurrence of 8 mitotic cycles in the cystocytes of A. mellifera and 7 in the meliponines, considering that only one spermatozoom originates of each final spermatogonium.

SURGICAL MANAGEMENT OF EPIBULBAR DERMOID CYST: A CASE REPORT

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Shubhangi Nigwekar P, Chaitanya Gupte P, Prajakta Kharche M, Akshay Beedkar U, Neeta Misra S, ParagTupe N

2015-04-01

Full Text Available ABSTRACT Dermoids are congenital lesions representing normal tissue in abnormal location. Orbital dermoid cysts are divided into superficial and deep dermoids. Depending on type and location, superficial ocular dermoid cysts are divided into limbal, dermoid cyst and epibulbar dermoid cyst or dermolipoma. The most common location for the epibulbar dermoid cyst is inferotemporal region of eye. They are usually asymptomatic or may present with inflammatory response due to leakage of cyst contents or may cause local irritation due to protruding hair and do cause cosmetic blemish to a school going child. For local irritation and cosmetic reasons, complete surgical excision with intact capsule of epibulbar dermoid cyst is mandatory to prevent acute inflammatory response and its recurrence. In this article we are presenting the clinical features and surgical management of an inferotemporal epibulbar dermoid in a male patient.

Synovial cysts of the lumbar spine

International Nuclear Information System (INIS)

Rosa, Ana Claudia Ferreira; Machado, Marcio Martins; Figueiredo, Marco Antonio Junqueira; Cerri, Giovanni Guido

2002-01-01

Intraspinal synovial cysts of the lumbar spine are rare and commonly associated with osteoarthritis of the facet joints, particularly at level L4-L5. Symptoms are uncommon and may include low-back pain or sciatica. These cysts are accurately diagnosed by using computed tomography and magnetic resonance imaging. Diagnosis is essential for the correct management of the cysts. Several treatment options are available including rest and immobilization, computed tomography guided corticosteroid injection, and surgery in patients that are nonresponsive to other treatment methods. (author)

Neurenteric cyst of the posterior mediastinum

International Nuclear Information System (INIS)

Setty, H.A.N.; Hegde, K.K.S.; Narvekar, V.N.

2005-01-01

We report a case of a large posterior mediastinal neurenteric cyst in a neonate demonstrated by chest radiographs, barium swallow examination, ultrasonography and CT of the thorax. All the investigations revealed a large posterior mediastinal cystic mass with vertebral anomalies in the form of scoliosis and hemivertebra. The cyst was completely excised by a right posterolateral thoracotomy and biopsy showed the features of a neurenteric cyst. The rarity of the lesion prompted us to report this case Copyright (2005) Blackwell Publishing Asia Pty Ltd

Developmental odontogenic cysts of jaws: a clinical study of 245 cases.

Science.gov (United States)

Yazdani, Javad; Kahnamouii, Shiva Solahaye

2009-01-01

The aim of this study was to investigate the relative frequency of developmental odontogenic cysts in an Iranian population. In this study 245 cysts from both jaws, treated in the Faculty of Dentistry at Tabriz University of Medical Sciences during a 10-year period from 1998 to 2008, were analyzed in order to evaluate the incidence of such cysts. We had permission from all the patients. Case histories of 65% of male and 35% of female patients were analyzed. The age of the patients varied from 14 to 64 years, with an average of 33.21 ± 10.89. In this 10-year study of odontogenic cysts, 97 cases were developmental odontogenic cysts with the following inci-dence: dentigerous cyst, 44%; odontogenic keratocyst, 36%; primordial cyst, 9%; Gorlin cyst, 2%; lateral periodontal cyst, 3%; eruption cyst, 3%; and gingival cyst, 3% (adults 2%, infants 1%). A total of 60% of the cysts were found in the mandible and 40% in the maxilla. Regarding the mandible, the molar region was involved in 47% of the cases, premolar region in 33% and anterior region in 20% (total = 100%). Regarding the maxilla, the canine-to-canine region was involved in 52% of the cases, premolar region in 20% and molar region in 28% (total = 100%). An important finding in this study was the fact that 39% of the jaw cysts were developmental odontogenic cysts and the most common developmental odontogenic cysts were dentigerous cyst and OKC (odontogenic keratocyst).

Radiologic Findings of Epidermal Cysts in the Trunk

International Nuclear Information System (INIS)

Kim, Myung Hyun; Chung, Jae Joon; Park, Kyoung Seuk; Park, Su Mi

2005-01-01

To evaluate the ultrasonographic (US) or computer tomography (CT) findings of surgically proven epidermal cysts in the trunk, and to compare the echogenicity of cysts with internal contents. Forty-five patients were retrospectively evaluated. US and CT findings of epidermal cysts were assessed in regard to location, size, shape, number, echogenicity, posterior sound enhancement, internal density, septa, mural nodule and calcification, perilesional infiltration, contrast enhancement, and internal contents. All 45 patients (M:F=29:16; US in 26, CT in 19) had only one cyst, and they were located in the buttocks (n=19), back (n=13), inguinal (n=4), posterior neck (n=3), perineum (n=2), abdominal wall (n=2), presternal (n=1), and axilla (n=1). Of 26 patients who underwent US, there were 8 cases of homogeneously hypoechoic mass (30.8%), 8 of inhomogeneously hypoechoic mass (30.8%), 7 of homogeneously hypoechoic mass with internal hypoechoic lines and echogenic spots (26.9%) and 3 of homogeneously hypoechoic mass with internal echogenic spots (11.5%). Posterior sound enhancement was noted in 21 patients (80.8%). Of 19 patients who underwent CT, there were 14 cases of simple cyst (73.7%) and 5 of abscess-like lesion (26.3%). Overlying skin thickening (n=13), contrast enhancement of cystic wall (n=11), perilesional infiltration (n=7), and internal septa (n=6) were demonstrated. The internal contents of the cysts were keratinous (n=27, 60.0%) or greasy (n=15, 33.3%) material. There was no statistical significance between the echogenicity of the cysts and the internal contents (p > 0.2). Epidermal cysts showed homogeneous or inhomogeneous hypoechoic mass with posterior sound enhancement on US. There was no relationship between the echogenicity of the cysts and the internal contents. In the case of ruptured cyst, an abscess-like lesion with wall enhancement and perilesional infiltration was noted on CT scan

Vanishing large ovarian cyst with thyroxine therapy.

Science.gov (United States)

Dharmshaktu, Pramila; Kutiyal, Aditya; Dhanwal, Dinesh

2013-01-01

A 21-year-old female patient recently diagnosed with severe hypothyroidism was found to have a large ovarian cyst. In view of the large ovarian cyst, she was advised to undergo elective laparotomy in the gynaecology department. She was further evaluated in our medical out-patient department (OPD), and elective surgery was withheld. She was started on thyroxine replacement therapy, and within a period of 4 months, the size of the cyst regressed significantly, thereby improving the condition of the patient significantly. This case report highlights the rare and often missed association between hypothyroidism and ovarian cysts. Although very rare, profound hypothyroidism that can cause ovarian cysts in an adult should always be kept in the differential diagnosis to avoid unnecessary ovarian surgery. Hypothyroidism should be considered in the differential diagnosis of adult females presenting with multicystic ovarian tumours.Adequate thyroid hormone replacement therapy can prevent these patients from undergoing unnecessary and catastrophic ovarian resection.Surgical excision should be considered only when adequate thyroid replacement therapy fails to resolve ovarian enlargement.In younger women with ovarian cysts, it is also desirable to avoid unnecessary surgery so as to not compromise fertility in the future.

Incidental pineal cysts in children who undergo 3-T MRI

International Nuclear Information System (INIS)

Whitehead, Matthew T.; Oh, Christopher C.; Choudhri, Asim F.

2013-01-01

Pineal cysts, both simple and complex, are commonly encountered in children. More cysts are being detected with MR technology; however, nearly all pineal cysts are benign and require no follow-up. To discover the prevalence of pineal cysts in children at our institution who have undergone high-resolution 3-T MRI. We retrospectively reviewed 100 consecutive 3-T brain MRIs in children ages 1 month to 17 years (mean 6.8 ± 5.1 years). We evaluated 3-D volumetric T1-W imaging, axial T2-W imaging, axial T2-W FLAIR (fluid attenuated inversion recovery) and coronal STIR (short tau inversion recovery) sequences. Pineal parenchymal and cyst volumes were measured in three planes. Cysts were analyzed for the presence and degree of complexity. Pineal cysts were present in 57% of children, with a mean maximum linear dimension of 4.2 mm (range 1.5-16 mm). Of these cysts, 24.6% showed thin septations or fluid levels reflecting complexity. None of the cysts demonstrated complete T2/FLAIR signal suppression. No cyst wall thickening or nodularity was present. There was no significant difference between the ages of children with and without cysts. Cysts were more commonly encountered in girls than boys (67% vs. 52%; P = 0.043). There was a slight trend toward increasing pineal gland volume with age. Pineal cysts are often present in children and can be incidentally detected by 3-T MRI. Characteristic-appearing pineal cysts in children are benign, incidental findings, for which follow-up is not required if there are no referable symptoms or excessive size. (orig.)

Pancreatic cyst development: insights from von Hippel-Lindau disease

Directory of Open Access Journals (Sweden)

van Asselt Sophie J

2013-02-01

Full Text Available Abstract Pancreatic cysts are a heterogeneous group of lesions, which can be benign or malignant. Due to improved imaging techniques, physicians are more often confronted with pancreatic cysts. Little is known about the origin of pancreatic cysts in general. Von Hippel-Lindau (VHL disease is an atypical ciliopathy and inherited tumor syndrome, caused by a mutation in the VHL tumor suppressor gene encoding the VHL protein (pVHL. VHL patients are prone to develop cysts and neuroendocrine tumors in the pancreas in addition to several other benign and malignant neoplasms. Remarkably, pancreatic cysts occur in approximately 70% of VHL patients, making it the only hereditary tumor syndrome with such a discernible expression of pancreatic cysts. Cellular loss of pVHL due to biallelic mutation can model pancreatic cystogenesis in other organisms, suggesting a causal relationship. Here, we give a comprehensive overview of various pVHL functions, focusing on those that can potentially explain pancreatic cyst development in VHL disease. Based on preclinical studies, cilia loss in ductal cells is probably an important early event in pancreatic cyst development.

Endoscopic modified medial maxillectomy for odontogenic cysts and tumours.

Science.gov (United States)

Nakayama, Tsugihama; Otori, Nobuyoshi; Asaka, Daiya; Okushi, Tetsushi; Haruna, Shin-ichi

2014-12-01

Odontogenic maxillary cysts and tumours originate from the tooth root and have traditionally been treated through an intraoral approach. Here, we report the efficacy and utility of endoscopic modified medial maxillectomy (EMMM) for the treatment of odontogenic maxillary cysts and a tumour. We undertook EMMM under general anaesthesia in six patients: four had radicular cysts, one had a dentigerous cyst, and one had a keratocystic odontogenic tumour. The cysts and tumours were completely excised and the inferior turbinate and nasolacrimal duct were preserved in all patients. There were no peri- or postoperative complications, and no incidences of recurrence. Endoscopic modified medial maxillectomy appears to be an effective and safe technique for treating odontogenic cysts and tumours.

Lymphoepithelial cyst of the pancreas: a case report

International Nuclear Information System (INIS)

Joo, Seung Ho; Kim, Myeong Jin; Kim, Ki Whang; Park, Young Nyun; Shim, Hyp Sup; Lim, Joon Seok

2005-01-01

We present a case of lymphoepithelial cyst of the pancreas. The cyst showed moderate echogenicity, mimicking a solid lesion on ultrasonography (US), and had a cystic appearance on computed tomography (CT). This ambivalent finding may be a distinctive feature of lymphoepithelial cysts of the pancreas

Radiofrequency Ablation of Hepatic Cysts : Case Report

International Nuclear Information System (INIS)

Lee, Ye Ri; Kim, Pyo Nyun

2005-01-01

Radiofrequency ablation has been frequently performed on intra-hepatic solid tumor, namely, hepatocellular carcinoma, metastatic tumor and cholangio carcinoma, for take the cure. But, the reports of radiofrequency ablation for intrahepatic simple cysts are few. In vitro experiment of animal and in vivo treatment for intrahepatic cysts of human had been reported in rare cases. We report 4 cases of radiofrequency ablation for symptomatic intrahepatic cysts

Multiple intracranial hydatid cysts: MR findings

International Nuclear Information System (INIS)

Pumar, J.; Alvarez, M.; Leira, R.; Prieto, J.M.; Arrojo, L.; Pereira, J.; Vidal, J.

1992-01-01

Multiple intracranial hydatid cysts are uncommon and usually localized in the supratentorial compartment. We report a case studied by CT and MR of multiple intracranial hydatid cysts scattered in various anatomic sites: supratentorial, infratentorial and also intraventricular. (orig.)

TH-AB-202-05: BEST IN PHYSICS (JOINT IMAGING-THERAPY): First Online Ultrasound-Guided MLC Tracking for Real-Time Motion Compensation in Radiotherapy

Energy Technology Data Exchange (ETDEWEB)

Ipsen, S; Bruder, R; Schweikard, A [University of Luebeck, Luebeck, DE (United States); O’Brien, R; Keall, P [University of Sydney, Sydney (Australia); Poulsen, P [Aarhus University Hospital, Aarhus (Denmark)

2016-06-15

Purpose: While MLC tracking has been successfully used for motion compensation of moving targets, current real-time target localization methods rely on correlation models with x-ray imaging or implanted electromagnetic transponders rather than direct target visualization. In contrast, ultrasound imaging yields volumetric data in real-time (4D) without ionizing radiation. We report the first results of online 4D ultrasound-guided MLC tracking in a phantom. Methods: A real-time tracking framework was installed on a 4D ultrasound station (Vivid7 dimension, GE) and used to detect a 2mm spherical lead marker inside a water tank. The volumetric frame rate was 21.3Hz (47ms). The marker was rigidly attached to a motion stage programmed to reproduce nine tumor trajectories (five prostate, four lung). The 3D marker position from ultrasound was used for real-time MLC aperture adaption. The tracking system latency was measured and compensated by prediction for lung trajectories. To measure geometric accuracy, anterior and lateral conformal fields with 10cm circular aperture were delivered for each trajectory. The tracking error was measured as the difference between marker position and MLC aperture in continuous portal imaging. For dosimetric evaluation, 358° VMAT fields were delivered to a biplanar diode array dosimeter using the same trajectories. Dose measurements with and without MLC tracking were compared to a static reference dose using a 3%/3 mm γ-test. Results: The tracking system latency was 170ms. The mean root-mean-square tracking error was 1.01mm (0.75mm prostate, 1.33mm lung). Tracking reduced the mean γ-failure rate from 13.9% to 4.6% for prostate and from 21.8% to 0.6% for lung with high-modulation VMAT plans and from 5% (prostate) and 18% (lung) to 0% with low modulation. Conclusion: Real-time ultrasound tracking was successfully integrated with MLC tracking for the first time and showed similar accuracy and latency as other methods while holding the

SU-F-T-574: MLC Based SRS Beam Commissioning - Minimum Target Size Investigation

Energy Technology Data Exchange (ETDEWEB)

Zakikhani, R [Florida Cancer Specialists - Largo, Largo, FL (United States); Able, C [Florida Cancer Specialists - New Port Richey, New Port Richey, FL (United States)

2016-06-15

Purpose: To implement a MLC accelerator based SRS program using small fields down to 1 cm × 1 cm and to determine the smallest target size safe for clinical treatment. Methods: Computerized beam scanning was performed in water using a diode detector and a linac-head attached transmission ion chamber to characterize the small field dosimetric aspects of a 6 MV photon beam (Trilogy-Varian Medical Systems, Inc.). The output factors, PDD and profiles of field sizes 1, 2, 3, 4, and 10 cm{sup 2} were measured and utilized to create a new treatment planning system (TPS) model (AAA ver 11021). Static MLC SRS treatment plans were created and delivered to a homogeneous phantom (Cube 20, CIRS, Inc.) for a 1.0 cm and 1.5 cm “PTV” target. A 12 field DMLC plan was created for a 2.1 cm target. Radiochromic film (EBT3, Ashland Inc.) was used to measure the planar dose in the axial, coronal and sagittal planes. A micro ion chamber (0.007 cc) was used to measure the dose at isocenter for each treatment delivery. Results: The new TPS model was validated by using a tolerance criteria of 2% dose and 2 mm distance to agreement. For fields ≤ 3 cm{sup 2}, the max PDD, Profile and OF difference was 0.9%, 2%/2mm and 1.4% respectively. The measured radiochromic film planar dose distributions had gamma scores of 95.3% or higher using a 3%/2mm criteria. Ion chamber measurements for all 3 test plans effectively met our goal of delivering the dose accurately to within 5% when compared to the expected dose reported by the TPS (1 cm plan Δ= −5.2%, 1.5 cm plan Δ= −2.0%, 2 cm plan Δ= 1.5%). Conclusion: End to end testing confirmed that MLC defined SRS for target sizes ≥ 1.0 cm can be safely planned and delivered.

Percutaneous treatment of liver hydatid cysts

Energy Technology Data Exchange (ETDEWEB)

Akhan, Okan; Oezmen, Mustafa N

1999-10-01

Hydatic disease caused by Echinococcus granulosus is an endemic disease and an important public health problem in some countries of the world. The results of surgical treatment are associated with a high rate of mortality, morbidity, postoperative recurrence and a long period of hospital stay and the medical treatment results are still controversial. Although the percutaneous aspiration and treatment of liver hydatid cysts were considered to be contraindicated due to risks of anaphylactic shock and dissemination of clear-crystal fluid into the abdomen, several reports of successful percutaneous treatment of liver hydatid cysts have been published in the literature. Today, percutaneous treatment of liver hydatid cysts is the most effective and reliable treatment procedure in the selected cases. In this review, indications, contraindications, method and techniques, healing criteria, complications, results and importance of the percutaneous treatment of liver hydatid cysts are discussed.

Percutaneous treatment of liver hydatid cysts

International Nuclear Information System (INIS)

Akhan, Okan; Oezmen, Mustafa N.

1999-01-01

Hydatic disease caused by Echinococcus granulosus is an endemic disease and an important public health problem in some countries of the world. The results of surgical treatment are associated with a high rate of mortality, morbidity, postoperative recurrence and a long period of hospital stay and the medical treatment results are still controversial. Although the percutaneous aspiration and treatment of liver hydatid cysts were considered to be contraindicated due to risks of anaphylactic shock and dissemination of clear-crystal fluid into the abdomen, several reports of successful percutaneous treatment of liver hydatid cysts have been published in the literature. Today, percutaneous treatment of liver hydatid cysts is the most effective and reliable treatment procedure in the selected cases. In this review, indications, contraindications, method and techniques, healing criteria, complications, results and importance of the percutaneous treatment of liver hydatid cysts are discussed

Gingival Cyst of Newborn.

Science.gov (United States)

Moda, Aman

2011-01-01

Gingival cyst of newborn is an oral mucosal lesion of transient nature. Although it is very common lesion within 3 to 6 weeks of birth, it is very rare to visualize the lesion thereafter. Presented here is a case report of gingival cyst, which was visible just after 15 days of birth. Clinical diagnoses of these conditions are important in order to avoid unnecessary therapeutic procedure and provide suitable information to parents about the nature of the lesion.

Peritoneal inclusion cysts: Changes on follow-up ultrasonography

International Nuclear Information System (INIS)

Kim, Jung Sik; Lee, Jin Hee; Lee, Hee Jung; Lee, Sung Moon; Woo, Seong Ku

2003-01-01

To evaluate the volume change of peritoneal inclusion cysts on the follow-up ultrasonography (US). From March 1995 to May 1999, thirty seven women with ultrasonographically diagnosed peritoneal inclusion cysts were included in this study. Six patients underwent surgery for several reasons. Follow-up ultrasonography was performed 70-456 days (mean=191 days) after initial US examination in 12 of the remaining 31 patient with no further treatment. US was performed with a 3.5 or 4 MHz transabdominal probe in all 18 patients who underwent either surgery or follow-up US, and additional tranvaginal US examination using a 5-7 MHz probe in 15 of 18 patients. The volume change of the cysts was recorded for each US examination. Three cysts (25%) (volume=170 cm 3 , 61 cm 3 , and 38 cm 3 , respectively) were completely resolved on the follow-up US while the other nine cysts showed a decreased volume in seven patients (58%) and increased volume in two patients (17%). Spontaneous regression of peritoneal inclusion cysts is more common than it is believed to be, and ultrasonography may be a useful follow-up examination for peritoneal inclusion cysts.

Unicameral (simple) bone cysts.

Science.gov (United States)

Baig, Rafath; Eady, John L

2006-09-01

Since their original description by Virchow, simple bone cysts have been studied repeatedly. Although these defects are not true neoplasms, simple bone cysts may create major structural defects of the humerus, femur, and os calcis. They are commonly discovered incidentally when x-rays are taken for other reasons or on presentation due to a pathologic fracture. Various treatment strategies have been employed, but the only reliable predictor of success of any treatment strategy is the age of the patient; those being older than 10 years of age heal their cysts at a higher rate than those under age 10. The goal of management is the formation of a bone that can withstand the stresses of use by the patient without evidence of continued bone destruction as determined by serial radiographic follow-up. The goal is not a normal-appearing x-ray, but a functionally stable bone.

Developmental odontogenic cysts of jaws: a clinical study of 245 cases

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Javad Yazdani

2009-06-01

Full Text Available Background and aims. The aim of this study was to investigate the relative frequency of developmental odontogenic cysts in an Iranian population. Materials and methods. In this study 245 cysts from both jaws, treated in the Faculty of Dentistry at Tabriz University of Medical Sciences during a 10-year period from 1998 to 2008, were analyzed in order to evaluate the incidence of such cysts. We had permission from all the patients. Case histories of 65% of male and 35% of female patients were analyzed. The age of the patients varied from 14 to 64 years, with an average of 33.21 ± 10.89. Results. In this 10-year study of odontogenic cysts, 97 cases were developmental odontogenic cysts with the following incidence: dentigerous cyst, 44%; odontogenic keratocyst, 36%; primordial cyst, 9%; Gorlin cyst, 2%; lateral periodontal cyst, 3%; eruption cyst, 3%; and gingival cyst, 3% (adults 2%, infants 1%. A total of 60% of the cysts were found in the mandible and 40% in the maxilla. Regarding the mandible, the molar region was involved in 47% of the cases, premolar region in 33% and anterior region in 20% (total = 100%. Regarding the maxilla, the canine-to-canine region was involved in 52% of the cases, premolar region in 20% and molar region in 28% (total = 100%. Conclusion. An important finding in this study was the fact that 39% of the jaw cysts were developmental odontogenic cysts and the most common developmental odontogenic cysts were dentigerous cyst and OKC (odontogenic keratocyst.

Bilateral radicular cyst in mandible: an unusual case report.

Science.gov (United States)

Bava, Fareed Ahmed; Umar, Dilshad; Bahseer, Bahija; Baroudi, Kusai

2015-02-01

A radicular cyst is one of the furthermost everyday odontogenic cysts of the anterior maxilla, not regularly comprehended in youth. They are found mostly at the apices of the tooth (periapical cyst), lateral surface of the roots (lateral radicular cyst) and remains in the jaw after removal of the offending tooth (residual cyst). The radicular cyst has been catalogued as an inflammatory cyst, as an outcome to pulpal necrosis succeeding caries, with a linked periapical inflammatory reaction. They advance sluggishly and asymptomatic lest infected. Because of this they can extent to big dimensions. Many times it is perplexing to segregate radicular cysts from the obligatory pre-existing chronic periapical periodontitis lesions radiographically. Here, we present a rare case with bilateral radicular cyst in relation to first molar of the mandible in a 19-year-old. Orthopantomograph showed a large unilocular radiolucency with a well-defined border in the periapical region of the first molar on the left side extending from the root of the second premolar to the mesial root of the second molar. Correspondingly another well-defined unilocular radiolucency with a well-defined border was seen on the right side of the mandible. Several treatment possibilities are presented for a radicular cyst such as surgical endodontic treatment, extraction of the transgressing tooth, enucleation with primary closure, and marsupialization trailed by enucleation. The patient management comprised surgical enucleation of cystic sac followed by rehabilitation of the same area.

Mapping genetic factors controlling potato - cyst nematode interactions

NARCIS (Netherlands)

Rouppe van der Voort, J.N.A.M.

1998-01-01

The thesis describes strategies for genetic mapping of the genomes of the potato cyst nematode and potato. Mapping in cyst nematodes was achieved by AFLP genotyping of single cysts and subsequent segregation analysis in a family of sibling populations. The genetic map of Globodera