• The Transactions of the Korean Institute of Electrical Engineers D
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• v.55 no.8
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• pp.369-374
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• 2006

Due to development of internet network environments and data compression techniques, the size and amount of multimedia data has greatly increased. They are compressed before transmission or storage. Dealing with these compressed data such as video retrieval or indexing requires decompression procedure in most cases. This causes additional computations and increases the processing time. In various applications a histogram is one of the most frequently used tools. Efficiency of extracting such histograms will drop down if decompression is involved. We propose a novel scheme for extracting histograms from images that are transformed into the compressed domain by 8x8 DCT(Discrete Cosine Transform). In this scheme an averaged version of original image is obtained by a simple linear combination of DCT coefficients with the sets of coefficients we designed.

• Journal of Biomedical Engineering Research
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• v.17 no.1
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• pp.33-42
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• 1996

A multimedia remote ultrasound image transfer system for tole-medical services was implemented. The image data of the ultrasound scanner system of the slave is compressed using image compression system. It is transferred to the master PC via ISDN UNI(User-Network Interface) and decompressd by image decompression system. The total system is composed of three parts; first, the image capture card which transfers bidirection- al data between ultrasound scanner system and PC, second, image compression and decompression card, finally, ISDN TA(Terminal Adaptor) card for transferring the image. This system has a easy user interface because it is executed on the basis of MS-WINDOWS. So it is capable of serving medical services at a remote place.

• Neurospine
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• v.15 no.4
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• pp.296-305
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• 2018

Cervical disc arthroplasty (CDA), or total disc replacement, has emerged as an option in the past two decades for the management of 1- and 2-level cervical disc herniation and spondylosis causing radiculopathy, myelopathy, or both. Multiple prospective randomized controlled trials have demonstrated CDA to be as safe and effective as anterior cervical discectomy and fusion, which has been the standard of care for decades. Moreover, CDA successfully preserved segmental mobility in the majority of surgical levels for 5-10 years. Although CDA has been suggested to have long-term efficacy for the reduction of adjacent segment disease in some studies, more data are needed on this topic. Surgery for CDA is more demanding for decompression, because indirect decompression by placement of a tall bone graft is not possible in CDA. The artificial discs should be properly sized, centered, and installed to allow movement of the vertebrae, and are commonly 6 mm high or less in most patients. The key to successful CDA surgery includes strict patient selection, generous decompression of the neural elements, accurate sizing of the device, and appropriately centered implant placement.

• Journal of Korean Neurosurgical Society
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• v.65 no.6
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• pp.853-860
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• 2022

Objective : This prospective, randomized, double-blinded trial aimed to evaluate the efficacy and safety of prophylactic ramosetron administration against postoperative nausea and vomiting (PONV) in patients undergoing microvascular decompression (MVD). Methods : In this study, 100 patients undergoing MVD were randomly allocated to the control (normal saline, 2 mL) or ramosetron (ramosetron, 0.3 mg) groups at the end of surgery. The incidence and severity of PONV, need for rescue antiemetics, patient satisfaction score, duration of hospital stay, and the occurrence of adverse events were evaluated 48 hours post-surgery. Results : Data obtained from 97 patients were included in the final analysis. The incidence of PONV was significantly lower in the ramosetron group than in the control group throughout the 48-hour postoperative period (29.2% vs. 51.0%, p=0.028). A similar trend was observed with regard to PONV severity (p=0.041). The need for rescue antiemetics, satisfaction score, duration of hospital stays, and the occurrence of adverse events did not significantly differ between the groups. Conclusion : Prophylactic ramosetron administration reduced the incidence and severity of PONV in patients undergoing MVD without causing serious adverse events. Thus, ramosetron use may improve patient recovery following MVD.

• Journal of Korean Neurosurgical Society
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• v.53 no.1
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• pp.1-5
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• 2013

Objective : The purpose of this study was to evaluate the characteristics and surgical outcomes of familial hemifacial spasm (HFS) and to discuss the role of genetic susceptibility. Methods : Between 2001 and 2011, 20 familial HFS patients with ten different pedigrees visited our hospital. The data from comprehensive evaluation of these patients, including clinical, radiological and electrophysiological data and surgical outcomes were reviewed to characterize familial HFS and to compare the characteristics between familial HFS and sporadic HFS. Results : According to the family tree, the inheritance pattern was difficult to define clearly using these data. Radiologic findings suggested that the vertebral artery (VA) was a more frequent offender in familial HFS than in sporadic cases (35.0% vs. 10.0%, p<0.001). Chi-square test showed that there were no correlation between VA tortuosity and underlying morbidity such as diabetes or hypertension (p=0.391). Eighteen out of 19 patients who underwent microvascular decompression showed no residual spasm. Other features of familial HFS overlap with sporadic cases. These findings suggest that certain genetic susceptibilities rather than hypertension or diabetes may influence vascular tortuosity and HFS development. Conclusion : In this study, familial HFS seems not so different from sporadic cases. Authors thought familial HFS could have heterogeneous etiology. Further study of familial HFS including clinical, anatomic, genetic, and molecular information may help identify a gene or trait that can provide insight into the mechanisms of sporadic and familial HFS.

• Journal of Acupuncture Research
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• v.37 no.4
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• pp.259-269
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• 2020

Background: This study aims to statistically analyze and compare the curative effect and satisfaction level between typical traditional Korean medicine treatment and nonsurgical spinal decompression treatment. Methods: Of the patients who were diagnosed with the cervical or lumbar herniated intervertebral disc at the Department of Acupuncture and Moxibustion Medicine at the Daejeon Korean Medicine Hospital from April 14^th to August 25^th, 2019, this study retrospectively analyzed the medical records of 31 patients who underwent nonsurgical spinal decompression treatment and traditional Korean medicine (assigned to Group A) and another 31 patients who received typical traditional Korean medicine alone (assigned to Group B). The clinical data were analyzed using IBM SPSS Version 23.0. Results: No statistically significant differences appeared in terms of sociodemographic, condition, and therapeutic characteristics, except whether the patient received Western medicine treatment, before or after a treatment with traditional Korean medicine. Group A exhibited higher variations in numeric rating scale, EuroQol- 5 dimension and EuroQol visual analogue scale scores compared to Group B as determined by independent sample t test and analysis of covariance. In addition, the satisfaction score of Group A was higher than that of Group B The result of cross analysis revealed that desire for continued treatment in Group A was higher than that of Group B. Conclusion: This retrospective observational study showed that the patients with nonsurgical spinal decompression treatment reported a greater reduction in pain, improved quality of life and satisfaction than patients receiving typical traditional Korean medicine.

• Korean Journal of Clinical Laboratory Science
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• v.43 no.1
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• pp.19-25
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• 2011

The purpose of this study was to analyse brainstem auditory evoked potentials (BAEP) wave change data during microvascular decompression (MVD). The nerve function of Cranial Nerve VIII is at risk during MVD. Intraoperative monitoring of BAEP can be a useful tool to decrease the danger of hearing loss. Between January and December 2009, 242 patients had MVD for hemifacial spasm (HFS) and trigeminal neuralgia (TN). Among intraoperative BAEP changes, amplitude of V-V' was the most frequently observed during cerebellar retraction and decompression step of the MVD procedure. 138 patients (57%) had no BAEP change while 104 patients (42.98%) had BAEP change. 69 patients (28.5%) had Type A-I, 16 patients (6.6%) had Type A-II, 5 patients (2.1%) had Type B, and 13 patients (5.37%) had Type C. MVD is a surgical procedure to relieve the symptoms (e.g. pain, muscle twitching) caused by compression of a nerve by an artery or vein. During BAEP intraoperative monitoring, the surgical step is important in interpreting the changes of wave V. Several potential mechanisms of injury may affect the cochlear nerve, and complete loss of BAEP is often associated with postoperative hearing loss. Intraoperative BAEP monitoring may provide an early warning of hearing disturbance after MVD.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.1
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• pp.84-89
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• 2019

JPEG is a most widely used standard image compression technology. This research introduces the JPEG image compression algorithm and describes each step in the compression and decompression. Image compression is the application of data compression on digital images. The DCT (discrete cosine transform) is a technique for converting a time domain to a frequency domain. First, the image is divided into 8 by 8 pixel blocks. Second, working from top to bottom left to right, the DCT is applied to each block. Third, each block is compressed through quantization. Fourth, the matrix of compressed blocks that make up the image is stored in a greatly reduced amount of space. Finally if desired, the image is reconstructed through decompression, a process using IDCT (inverse discrete cosine transform). The purpose of this research is to review all the processes of image compression / decompression using the discrete cosine transform method.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.42 no.2 s.332
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• pp.73-82
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• 2005

Test data volume and power consumption for scan vectors are two major problems in system-on-a-chip testing. Therefore, this paper proposes a new test data compression/decompression method for low power testing. The method is based on analyzing the factors that influence test parameters: compression ratio, power reduction and hardware overhead. To improve the compression ratio and the power reduction ratio, the proposed method is based on Modified Statistical Coding (MSC), Input Reduction (IR) scheme and the algorithms of reordering scan flip-flops and reordering test pattern sequence in a preprocessing step. Unlike previous approaches using the CSR architecture, the proposed method is to compress original test data, not $T_{diff}$, and decompress the compressed test data without the CSR architecture. Therefore, the proposed method leads to better compression ratio with lower hardware overhead and lower power consumption than previous works. An experimental comparison on ISCAS '89 benchmark circuits validates the proposed method.

• Proceedings of the IEEK Conference
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• 2000.06b
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• pp.242-245
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• 2000

In this paper we present new idea to highly compress the images. The previous image is transformed with wavelet and the transformed data are transmitted. The previous image is subtracted from the next image. Then difference values per pixel are scanned to search motion areas and boundaries. In the motion boundaries, motion vectors and error values are transformed with wavelet and transmitted. We also include camera motion estimation and compensation. In this method this system has advantages of more compressive data, better quality of picture and shorter processing time compared to MPEG2, MPEG4.