This paper presents a three-dimensional electronic laparoscopy system, including three-dimensional laparoscope pipe and medical video system. The three-dimensional laparoscope pipe adopts a dual-optical structure, which can collect three-dimensional information of the surgical region. By selecting a reasonable initial structure, the MTF curve of the objective lens is close to the diffraction limit, and the distortion is less than 25%. The medical video system also achieved high-definition image with 1 080 P, 30 Hz by GPU. At the mean time, the three-dimensional electronic laparoscope has achieved quantitative production and has been tested in a number of animals, which has broad application prospects and significant clinical application value.
Electronics, Medical ; Imaging, Three-Dimensional ; Laparoscopes ; Laparoscopy

Medical students and doctors should study the appearance of normal anatomical structures in the magnetic resonance images (MRIs). For this purpose, horizontal, coronal, sagittal MRIs of a healthy entire body and corresponding segmented images were prepared. However, it is inconvenient to select interesting MRIs and segmented images; and it is difficult to understand how stereoscopic anatomical structures appear in the MRIs. Therefore, in this research, a software, on which interesting MRIs can be conveniently displayed among the horizontal, coronal, sagittal MRIs and corresponding segmented images can be displayed together, was composed. And after stacking the segmented images, three-dimensional (3D) image of each anatomical structure was manually reconstructed by surface rendering. Then another software, on which interesting 3D images of anatomical structures can be displayed and rotated, was composed too. These softwares are expected to help medical students and doctors understand normal anatomical structures in the MRIs and read pathological findings in the MRIs of patients.
Humans ; Imaging, Three-Dimensional* ; Magnetic Resonance Imaging* ; Students, Medical

No abstract available.
*Diagnostic Imaging ; Human ; Radiology/*trends ; Radiology, Interventional ; Specialties, Medical

This paper mainly introduces the material composition and structure of two kinds of compound tabletop which currently used in large medical imaging equipment, also introduces the proper material choosing and production processing, together with the advantage and shortage of this two kinds of tabletop and different application occasion.
Construction Materials ; Diagnostic Imaging ; instrumentation ; Durable Medical Equipment

PURPOSE: Diffusion-weighted magnetic resonance imaging (DWI) has been known to visualize hyperacute ischemic stroke. And it takes only a few minutes to do. Moreover only a small amount of time and little cost is required to add T2-weighted imaging (T2WI) to DWI. The purpose of this study is to determine the usefulness of T2WI in addition to DWI as a primary imaging modality for patients with suspected ischemic stroke. METHODS: DWI plus T2WI was performed from January to May 2001 on the patients with suspected ischemic stroke. Two emergency physicians reviewed the films and medical records. The sensitivity and the specificity of DWI and T2WI for acute ischemic stroke were calculated. The agreement between DWI and T2WI was calculated using kappa statistics. RESULTS: A total of 241 patients were enrolled. Acute ischemic stroke was confirmed in 86 (35.7%) patients. The sensitivity and the specificity of DWI for acute ischemic stroke were 94.2% and 98.7%, and those for T2WI were 60.5% and 94.2%, respectively. The kappa value was 0.721 (p<0.01). Among the 86 acute ischemic stroke patients, the number of cases who presented less than 6 hours after symptom onset was significantly lower in the T2WI positive group (31% vs. 68.7%, p<0.05). CONCLUSION: This study suggests that the addition of T2WI to DWI as a primary imaging modality for acute ischemic stroke has little benefit compared to DWI alone, especially, when the symptom duration has been less than 6 hours.
Emergencies ; Humans ; Magnetic Resonance Imaging* ; Medical Records ; Sensitivity and Specificity ; Stroke*

This study presents an electronic portal imaging devices (EPIDs) based on daily check tool for Linac that is usable for different cancer centers.Several images of open rectangle fields were acquired with EPID and the key items of daily Linac check were derived from the obtained images using an in-house developed automatic analysis software.The experiment results showed that each parameter calculated by this tool is as reliable as the corresponding result measured by the commercial quality assurance devices and its measuring efficiency is much higher.
Electronics, Medical ; Electrons ; Particle Accelerators ; Phantoms, Imaging ; Radiometry ; Software

Image registration methods based on mutual information, including mutual information and normalized mutual information, have been accepted as the most accurate and efficient methods. But there are many fluctuations in the registration functions that hinder the optimization procedure and lead to registration failure in intra-modal registration. We found that besides the interpolation artifacts, the uncertainty of the changing of entropy with the changing of overlap also contributes to the fluctuations. The effect of interpolation artifacts can be eliminated, but it is difficult to eliminate the effect of uncertainty of entropy. Luckily, this effect is not significant in normalized mutual information. Normalized mutual information is more stable and robust than standard mutual information and its better performance and wider application can be expected.
Algorithms ; Diagnostic Imaging ; Humans ; Image Processing, Computer-Assisted ; methods ; Magnetic Resonance Imaging ; methods ; Medical Informatics ; methods ; Registries

OBJECTIVE: To evaluate the clinical usefulness of sonoelastography in infants with congenital muscular torticollis (CMT). METHODS: The medical records of 215 infants clinically diagnosed with CMT were retrospectively reviewed. Fifty-three infants met the inclusion criteria as follows: 1) infants diagnosed as CMT with a palpable neck mass before 3 months of age, 2) infants who were evaluated initially by both B-mode ultrasonography and sonoelastography, and 3) infants who had received physical therapy after being diagnosed with CMT. We checked the thickness of the sternocleidomastoid (SCM) muscles in B-mode ultrasonography, strain ratio of the SCM muscles in sonoelastography, and treatment duration. We evaluated the correlation between the treatment duration and the following factors: SCM muscle thickness, ratio of SCM muscle thickness on the affected to unaffected side (A/U ratio), and strain ratio. RESULTS: Both the thickness of the affected SCM muscle and the A/U ratio did not show significant correlation with the treatment duration (p=0.66, p=0.90). The strain ratio of the affected SCM muscle was significantly greater than that of the unaffected SCM muscle (p<0.001), and the strain ratio showed significant correlation with the treatment duration (p=0.001). CONCLUSION: Sonoelastography may be a useful adjunctive tool to B-mode ultrasonography for evaluating infants with CMT, especially when predicting their rehabilitation outcomes.
Elasticity Imaging Techniques* ; Humans ; Infant* ; Medical Records ; Muscles ; Neck ; Prognosis ; Rehabilitation ; Retrospective Studies ; Torticollis* ; Ultrasonography

In clinical surgery, there are frequent needs for communication between the house staff and the attending physician in an emergency situation. It's often insufficient for the house staff to make a decision through the information which is delivered in the form of only voice through the telephone line. To overcome the limitation of voice communication, we have designed an emergency teleradiology system which can be used for emergency surgical and medical decision making. The system can transmit the high quality images of CT, MRI, and other X-ray data using a PC attached to a modem through the conventional telephone line. Progressive transmission adopted in the system enables us to efficiently utilize the band-width of telephone line which is typically very low. The iterative residual coding/decoding algorithm compresses various medical images effectively, and thus fast-transmission of images date helps the house staff to perceive the status of emergent patient and make a fast and correct decision about the patient. The system also satisfies design requirements such as low-cost, ease of operation and interactive image communication including voice. 'Teleradiology system' proposed in this paper has been installed and operated in the emergency care unit of Severance Hospital, and as a result, it is effective in the emergency situations.
Decision Making ; Emergencies ; Emergency Medical Services ; Humans ; Internship and Residency ; Magnetic Resonance Imaging ; Modems ; Telephone ; Teleradiology* ; Voice

OBJECTIVE: With the increased use of interspinous spacers in the treatment of lumbar stenosis, knowledge of the geometry of the interspinous space is important. To prevent dislodgment of an interspinous spacer, the accurate depth and width of the interspinous space needs to be established to facilitate the best intraoperative selection of correct spacer size. METHODS: To determine the depth and width of the interspinous space, two methods are available which utilize plain film and magnetic resonance imaging (MRI). Data analysis of the interspinous depth and width was undertaken in 100 patients. RESULTS: The standard deviations were variable, since skin thickness (zone 1) was altered by sex and age. The difference in the zone 1 distance between adjacent interspinous processes varied according to gender (p<0.05), but was not influenced by age [p=0.32 by analysis of variance between groups (ANOVA)]. Zone 2, the supraspinous, and zone 3, the interspinous ligament depths, comprise the operative working area during insertion of an interspinous spacer. There were no differences with regard to gender or age (p>0.05). For zones 6 and 7, the interspinous distances at the narrowest and widest points, respectively, were found to decrease with the aging process, but the decrease was not statistically significant. There were no differences with regard to gender (p>0.05). CONCLUSION: This study provides additional information on the interspinous space. This statistical data are valuable for use in the design of interspinous spacers.
Academic Medical Centers* ; Aging ; Constriction, Pathologic ; Humans ; Ligaments ; Magnetic Resonance Imaging ; Skin ; Statistics as Topic