• Physical Therapy Korea
• /
• v.29 no.2
• /
• pp.106-116
• /
• 2022

Background: Shoulder external rotation exercises are commonly used to improve the stabilizing ability of the infraspinatus. However, during exercise, excessive activation of the posterior deltoid compared to the infraspinatus causes the humeral head to move anteriorly in an abnormal position. Many researchers have emphasized selective activation of the infraspinatus during shoulder external rotation exercise. Objects: This study aims to delineate the optimal exercise method for selective activation of infraspinatus by investigating the muscle activities of the infraspinatus and posterior deltoid according to the four shoulder exercise methods and two forearm positions. Methods: Thirty healthy individuals participated in this study. The participants were instructed to perform shoulder external rotation exercises following four exercise methods: sitting external rotation (SIER); standing external rotation at 90° abduction (STER); prone external rotation at 90° abduction (PRER); side-lying external rotation (SLER), and two forearm positions (neutral, supinated). The electromyography (EMG) signal amplitude was measured during each exercise. Surface EMG signals were recorded from the posterior deltoid, infraspinatus, and biceps brachii. Results: EMG results of the infraspinatus and posterior deltoid in PRER, were significantly higher than that of the other exercises (p < 0.01). The EMG ratio (infraspinatus/posterior deltoid) in SIER was significantly higher than that of the other exercises. EMG activation of the posterior deltoid in SIER, PRER, and SLER was significantly higher in neutral than in supinated (p < 0.01). Furthermore, the EMG of the infraspinatus in SIER was significantly higher in neutral than in supinated (p < 0.01). The EMG ratio (infraspinatus/ posterior deltoid) in SIER was significantly higher in neutral than in supinated (p < 0.05.) Contrarily EMG ratios in PRER and SLER were significantly higher in supinated than in neutral (p < 0.05). Conclusion: The results show that clinicians should consider these exercise methods and forearm positions when planning shoulder external rotation exercises for optimal shoulder rehabilitation.

• Journal of the Korean Society of Radiology
• /
• v.84 no.5
• /
• pp.1134-1139
• /
• 2023

Merkel cell carcinoma (MCC) is a rare malignant cutaneous tumor primarily located in the head and neck. We report the imaging features of pathologically confirmed MCC in the trunk. On US, MCC showed heterogeneous echogenicity with perpendicular hypoechoic linear bands that resembled "columns of smoke" in the skin and subcutaneous layers as well as prominent vascularity. On MRI, the tumor showed hypointensity on T1-weighted images and hyperintensity on proton density and T2-weighted images with linear low-signal bands in the skin and subcutaneous layers as well as intense enhancement on T1-enhanced images. Although MCC has nonspecific imaging features, these characteristics may be helpful for the early diagnosis of this disease.

• Journal of the Korean Society of Radiology
• /
• v.16 no.7
• /
• pp.897-904
• /
• 2022

The purpose of this study is to compare the difference in dose and image quality when applying the diagnostic reference level (DRL) test conditions for head radiography in a digital radiation environment and the test conditions currently applied in clinical practice. I would like to review the conditions of radiographic examination. In this study, the head model phantom was targeted, and the investigation conditions were divided into clinical conditions (Clinic), DRL value (DRL₇₅), and DRL average value (DRL_mean). For dose, Enterance surface dose (ESD) was measured, and for image quality, signal-to-noise ratio and contrast-to-noise ratio were measured and analyzed for comparison. The average values of skull anterior posterior(AP) ESD according to the changes in test conditions were Clinic 1214.03±4.21 µGy, DRL₇₅ 3017.83±8.14 µGy, DRL_mean 2283.50±7.09 µGy, and skull lateral (Lat). The average value of ESD was statistically significant with Clinic 762.79±3.54 µGy, DRL₇₅ 2168.57±10.83 µGy, and DRL_mean 1654.43±6.48 µGy (p<0.01). The average values of SNR and CNR measured in the orbital, maxillary sinus, frontal sinus, and sella turcica were statistically significant (p<0.01). As a result of this study, compared to DRL, the conditions used in clinical practice showed lower dose levels of about 58% for AP and about 70% for Lat., and there was no qualitative difference in terms of image quality. Through this study, it is necessary to consider a new diagnostic reference level suitable for the digital radiation environment, and it is considered that the dose should be reduced accordingly.

• Investigative Magnetic Resonance Imaging
• /
• v.1 no.1
• /
• pp.103-107
• /
• 1997

Purpose: To investigate the localization and functional lateralization of the supplementary motor area (SMA) in motor activation tests in comparison to that of the primary motor area. Materials and Methods: Seven healthy volunteers obtained echoplanar imaging blood oxygen level dependent technique. This study was carried on 1.5T Siemens Magnetom Vision system with the standard head coil. Parameters of EPI were followed as; TR/TE : 1.0/66.0msec, flip angle: $90^{\circ}$, field of view: $22cm{\times}22cm,{\;}matrix:{\;}128{\times}128$, slice number/slice thickness/gap: 1O/4mm/0.8mm with fat suppression technique. Motor task as finger opposition in each hand consisted of 3 sets of alternative rest and activation periods. Postprocessing were done on Stimulate 5.0 by using cross-correlation statistics. To compare the functional lateralization of the SMA in the right and left hand tests, each examination was evaluated for the percent change of signal intensity and the number of activated voxels both in the SMA and in the pri¬mary motor area. Hemispheric asymmetry was defined as difference of summation of the activted voxels between each hemisphere. Results: Percent change of signal intensity in the SMA (2.49 -3.06%) is lower than that of primary motor area(4.4 -7.23%). Percent change of signal intensity including activated voxels were observed almost equally in the right and left SMA. As for summation of activated voxels, primary motor area had significant difference between each hemisphere but not did the SMA. Conclusion: Preferred contralateral dominant hemisphere and hemispheric asymmetry were detected in the primary motor area but not in the SMA.

• Investigative Magnetic Resonance Imaging
• /
• v.6 no.1
• /
• pp.64-72
• /
• 2002

Purpose : To introduce and demonstrate the advantages of the new hybrid two-dimensional (2D) proton spectroscopic imaging (SI) over the single voxel spectroscopy (SVS) and conventional 2D SI in the clinical application of spectroscopy for pediatric cerebral disease. Materials and Methods : Eighty-one hybrid 2D proton spectroscopic imaging was performed in 79 children (36 normal infants and children, 10 with hypoxic-ischemic injury, 20 with toxic-metabolic encephalopathy, seven with brain tumor, three with meningoencephalitis, one with neurofibromatosis, one with Sturge-Weber syndrome and one with lissencephaly) ranging in age from the third day of life to 15 years. In adult volunteers (n=5), all three techniques including hybrid 2D proton SI, SVS using PRESS sequence, and conventional 2D proton SI were performed. Both hybrid 2D proton SI and SVS using PRESS sequence were performed in clinical cases (n=). All measurements were performed with a 1.5-T scanner using standard head quadrature coil. The 16$\times$16 phase encoding steps were set on variable field of view (FOV) depending on the size of the brain. The hybrid volume of interest inside FOV was set as $75{\times}75{\times}15{\;}\textrm{mm}^3$ or smaller to get rid of unwanted fat signal. Point-resolved spectroscopy (TR/TE=1,500 msec/135 or 270msec) was employed with standard chemical shift selective saturation (CHESSI pulses for water suppression. The acquisition time and spectral quality of hybrid 2D proton SI were compared with those of SVS and conventional 2D proton SI. Results : The hybrid 2D proton SI was successfully conducted upon all patients.

• Radiation Oncology Journal
• /
• v.24 no.4
• /
• pp.300-308
• /
• 2006

$\underline{Purpose}$: To develop a wireless CCTV system in semi-beam's eye view (BEV) to monitor daily patient setup in radiation therapy. $\underline{Materials\;and\;Methods}$: In order to get patient images in semi-BEV, CCTV cameras are installed in a custom-made acrylic applicator below the treatment head of a linear accelerator. The images from the cameras are transmitted via radio frequency signal (${\sim}2.4\;GHz$ and 10 mW RF output). An expected problem with this system is radio frequency interference, which is solved utilizing RF shielding with Cu foils and median filtering software. The images are analyzed by our custom-made software. In the software, three anatomical landmarks in the patient surface are indicated by a user, then automatically the 3 dimensional structures are obtained and registered by utilizing a localization procedure consisting mainly of stereo matching algorithm and Gauss-Newton optimization. This algorithm is applied to phantom images to investigate the setup accuracy. Respiratory gating system is also researched with real-time image processing. A line-laser marker projected on a patient's surface is extracted by binary image processing and the breath pattern is calculated and displayed in real-time. $\underline{Results}$: More than 80% of the camera noises from the linear accelerator are eliminated by wrapping the camera with copper foils. The accuracy of the localization procedure is found to be on the order of $1.5{\pm}0.7\;mm$ with a point phantom and sub-millimeters and degrees with a custom-made head/neck phantom. With line-laser marker, real-time respiratory monitoring is possible in the delay time of ${\sim}0.17\;sec$. $\underline{Conclusion}$: The wireless CCTV camera system is the novel tool which can monitor daily patient setups. The feasibility of respiratory gating system with the wireless CCTV is hopeful.

• Progress in Medical Physics
• /
• v.26 no.4
• /
• pp.193-200
• /
• 2015

The aim of this study is to present commissioning results of the ViewRay system. We verified safety functions of the ViewRay system. For imaging system, we acquired signal to noise ratio (SNR) and image uniformity. In addition, we checked spatial integrity of the image. Couch movement accuracy and coincidence of isocenters (radiation therapy system, imaging system and virtual isocneter) was verified. Accuracy of MLC positioing was checked. We performed reference dosimetry according to American Association of Physicists in Medicine (AAPM) Task Group 51 (TG-51) in water phantom for head 1 and 3. The deviations between measurements and calculation of percent depth dose (PDD) and output factor were evaluated. Finally, we performed gamma evaluations with a total of 8 IMRT plans as an end-to-end (E2E) test of the system. Every safety system of ViewRay operated properly. The values of SNR and Uniformity met the tolerance level. Every point within 10 cm and 17.5 cm radii about the isocenter showed deviations less than 1 mm and 2 mm, respectively. The average couch movement errors in transverse (x), longitudinal (y) and vertical (z) directions were 0.2 mm, 0.1 mm and 0.2 mm, respectively. The deviations between radiation isocenter and virtual isocenter in x, y and z directions were 0 mm, 0 mm and 0.3 mm, respectively. Those between virtual isocenter and imaging isocenter were 0.6 mm, 0.5 mm and 0.2 mm, respectively. The average MLC positioning errors were less than 0.6 mm. The deviations of output, PDDs between mesured vs. BJR supplement 25, PDDs between measured and calculated and output factors of each head were less than 0.5%, 1%, 1% and 2%, respectively. For E2E test, average gamma passing rate with 3%/3 mm criterion was $99.9%{\pm}0.1%$.

• The Journal of Korean Society for Radiation Therapy
• /
• v.18 no.1
• /
• pp.1-5
• /
• 2006

Purpose: IMRT quality assurance(Q.A) is consist of the absolute dosimetry using ionization chamber and relative dosimetry using the film. We have in general used 0.015 cc ionization chamber, because small size and measure the point dose. But this ionization chamber is too small to give an accurate measurement value. In this study, we have examined the degree of calculated to measured dose difference in intensity modulated radiotherapy(IMRT) based on the observed/expected ratio using various kinds of ion chambers, which were used for absolute dosimetry. Materials and Methods: we peformed the 6 cases of IMRT sliding-window method for head and neck cases. Radiation was delivered by using a Clinac 21EX unit(Varian, USA) generating a 6 MV x-ray beam, which is equipped with an integrated multileaf collimator. The dose rate for IMRT treatment is set to 300 MU/min. The ion chamber was located 5cm below the surface of phantom giving 100cm as a source-axis distance(SAD). The various types of ion chambers were used including 0.015cc(pin point type 31014, PTW. Germany), 0.125 cc(micro type 31002, PTW, Germany) and 0.6 cc(famer type 30002, PTW, Germany). The measurement point was carefully chosen to be located at low-gradient area. Results: The experimental results show that the average differences between plan value and measured value are ${\pm}0.91%$ for 0.015 cc pin point chamber, ${\pm}0.52%$ for 0.125 cc micro type chamber and ${\pm}0.76%$ for farmer type 0.6cc chamber. The 0.125 cc micro type chamber is appropriate size for dose measure in IMRT. Conclusion: IMRT Q.A is the important procedure. Based on the various types of ion chamber measurements, we have demonstrated that the dose discrepancy between calculated dose distribution and measured dose distribution for IMRT plans is dependent on the size of ion chambers. The reason is small size ionization chamber have the high signal-to-noise ratio and big size ionization chamber is not located accurate measurement point. Therefore our results suggest the 0.125 cc farmer type chamber is appropriate size for dose measure in IMRT.

• Journal of Microbiology
• /
• v.45 no.2
• /
• pp.158-167
• /
• 2007

In this study, we have cloned a novel cDNA encoding for a papain-family cysteine protease from the Uni-ZAP XR cDNA library of the polychaete, Periserrula leucophryna. This gene was expressed in Escherichia coli using the T7 promoter system, and the protease was characterized after partial purification. First, the partial DNA fragment (498 bp) was amplified from the total RNA via RT-PCR using degenerated primers derived from the conserved region of cysteine protease. The full-length cDNA of cysteine protease (PLCP) was prepared via the screening of the Uni-ZAP XR cDNA library using the $^{32}P-labeled$ partial DNA fragment. As a result, the PLCP gene was determined to consist of a 2591 bp nucleotide sequence (CDS: 173-1024 bp) which encodes for a 283-amino acid polypeptide, which is itself composed of an 59-residue signal sequence, a 6-residue propeptide, a 218-residue mature protein, and a long 3'-noncoding region encompassing 1564 bp. The predicted molecular weights of the preproprotein and the mature protein were calculated as 31.8 kDa and 25 kDa, respectively. The results of sequence analysis and alignment revealed a significant degree of sequence similarity with other eukaryotic cysteine proteases, including the conserved catalytic triad of the $Cys^{90},\;His^{226},\;and\;Asn^{250}$ residues which characterize the C1 family of papain-like cysteine protease. The nucleotide and amino acid sequences of the novel gene were deposited into the GenBank database under the accession numbers, AY390282 and AAR27011, respectively. The results of Northern blot analysis revealed the 2.5 kb size of the transcript and ubiquitous expression throughout the entirety of the body, head, gut, and skin, which suggested that the PLCP may be grouped within the cathepsin F-like proteases. The region encoding for the mature form of the protease was then subcloned into the pT7-7 expression vector following PCR amplification using the designed primers, including the initiation and termination codons. The recombinant cysteine proteases were generated in a range of 6.3 % to 12.5 % of the total cell proteins in the E. coli BL21(DE3) strain for 8 transformants. The results of SDS-PAGE and Western blot analysis indicated that a cysteine protease of approximately 25 kDa (mature form) was generated. The optimal pH and temperature of the enzyme were determined to be approximately 9.5 and $35^{\circ}C$, respectively, thereby indicating that the cysteine protease is a member of the alkaline protease group. The evaluation of substrate specificity indicated that the purified protease was more active towards Arg-X or Lys-X and did not efficiently cleave the substrates with non-polar amino acids at the P1 site. The PLCP evidenced fibrinolytic activity on the plasminogen-free fibrin plate test.

• The Journal of the Acoustical Society of Korea
• /
• v.30 no.4
• /
• pp.181-189
• /
• 2011

According to developments of digital signal processing, 3D sound come into focus on multimedia systems. Many studies on 3d sound have proposed lots of clues to create realistic sounds. But these clues are only focused on binaural systems which two ears are normal. If we make the 3d sound using those clues at monaural systems, the performance goes down dramatically. In order to use the clues for monaural systems, we have studies algorithms such as duplex theory. In duplex theory, the sounds that we listen are affected by human's body, pinna and shoulder. So, we can enhance sound localization performances using its characteristics. In this paper, we propose a new method to use psychoacoustic theory that creates realistic 3D audio at monaural systems. To improve 3d sound, we calculate the excitation energy rates of each symmetric HRTF and extract the weights in each bark range. Finally, they are applied to emphasize the characteristics related to each direction. Informal listening tests show that the proposed method improves sound localization performances much better than the conventional methods.