Do Magnets Have the Potential to Serve as a Stabilizer for the Shoulder Joint in Massive Rotator Cuff Tears?: A Biomechanical Cadaveric Study

Background@#Disruption of the rotator cuff muscles compromises concavity compression force, which leads to superior migration of the humeral head and loss of stability. A novel idea of using the magnetic force to achieve shoulder stabilization in massive rotator cuff tears (MRCTs) was considered because the magnets can stabilize two separate entities with an attraction force. This study aimed to investigate the biomechanical effect of the magnetic force on shoulder stabilization in MRCTs. @*Methods@#Seven fresh frozen cadaveric specimens were used with a customized shoulder testing system. Three testing conditions were set up: condition 1, intact rotator cuff without magnets; condition 2, an MRCT without magnets; condition 3, an MRCT with magnets. For each condition, anterior-posterior translation, superior translation, superior migration, and subacromial contact pressure were measured at 0°, 30°, and 60° of abduction. The abduction capability of condition 2 was compared with that of condition 3. @*Results@#The anterior-posterior and superior translations increased in condition 2; however, they decreased compared to condition 2 when the magnets were applied (condition 3) in multiple test positions and loadings (p <0.05). Abduction capability improved significantly in condition 3 compared with that in condition 2, even for less deltoid loading (p < 0.05). @*Conclusions@#The magnet biomechanically played a positive role in stabilizing the shoulder joint and enabled abduction with less deltoid force in MRCTs. However, to ensure that the magnet is clinically applicable as a stabilizer for the shoulder joint, it is necessary to thoroughly verify its safety in the human body and to conduct further research on technical challenges.

A universal ultrasound diagnostic system developed to support urology and coloproctological applications

In this study, we sought to describe a novel imaging apparatus that is lightweight, inexpensive, and highly eff ective for use in colorectal diagnostic and treatment settings. Typical probes for use in colorectal ultrasonic imaging applications are developed for surgeons to diagnose and stage rectal tumors and image the rectum and anus. Here we outline a new technique and use it for colorectal imaging in an animal. This technique involves use of an ultrasound array module positioned along the axis of rotation such that improved rotation is possible. This module is in the shape of a linear rod with a rotary linear component that allows for emission of focused ultrasonic echo signals from a linear section of the probe. The usability of the transducer and rectal image quality are satisfactory in a porcine model with the technique proposed here, axial/lateral resolution as 0.96/2.24 mm with 6 dB applied through the contour map using the point spread function. When compared to currently available methods, this technique provides superior diagnostic 3D volumetric image quality with reduced acquisition time. Given this, the ultrasound device proposed here may prove a viable and preferable method to those currently available for urology and colorectal imaging applications.

Hemiarthroplasty for Hip Fractures in Elderly Patients over 80 Years Old - Comparative Analysis between Femoral Neck Fracture and Intertrochanteric Fracture - / 대한고관절학회지

PURPOSE: The purpose of this study is to investigate the relative surgical risk and problems in hip hemiarthroplasty for treatment of an unstable intertrochanteric fracture in elderly patients over 80 years old. MATERIALS AND METHODS: Between April 2005 and May 2010, 58 patients whose age was over 80 years were available for inclusion in this study. They were divided into two groups: group 1 included 30 patients with femoral neck fracture and group 2 included 28 patients with intertrochanteric fracture. No significant differences in average age, concomitant disease, and walking ability before development of fracture were noted between the two groups. The following factors, including interval from development of fracture to operation, operation time, amount of blood loss, start time of walking after operation, duration of hospital stay, complications, revision rate, and walking ability were compared between the two groups. RESULTS: Operation time was an average of 85.2 minutes in group 1 and 97.5 minutes in group 2(P=0.03). The amount of bleeding was an average of 483 cc in group 1 and 695 cc in group 2(P=0.006). Similar results for walking start and recovery of walking ability after operation were observed in the two groups. No significant differences were observed in duration of hospital stay, complications, and revision rate. While 25 patients in group 1(83.3%) showed restoration of walking ability after operation to the same level of walking before injury, 19 patients in group 2(67.8%) showed restoration of walking ability postoperatively. CONCLUSION: Even though patients in group 2 showed a longer operation time and a higher amount of blood loss, compared with those in group 1, patients in group 2 had similar surgical risk and complications, compared with those in group 1. Therefore, primary hip hemiarthropalsty could be a good treatment option for intertrochanteric fracture in elderly.

The Influence of Fat Infiltration of Back Extensor Muscles on Osteoporotic Vertebral Fractures

STUDY DESIGN: Retrospective study. PURPOSE: To investigate the influence of fat infiltration at low back extensor muscles on osteoporotic vertebral fracture. OVERVIEW OF LITERATURE: In persons with stronger back muscles, the risk of osteoporotic vertebral fractures will likely be lower than in those persons with weaker back muscles. However, the degree of influence of fat infiltration of the back extensor muscle on osteoporotic vertebral fracture remains controversial. METHODS: Two hundred and thirty-seven patients who had undergone lumbar spine magnetic resonance imaging and bone mineral density (BMD) were enrolled in this study. The amount of low back extensor muscle was determined using the pseudocoloring technique on an axial view of the L3 level. The patients were divided into two groups: osteoporotic vertebral fracture group (group A) and non-fracture group (group B). The amount of low back extensor muscle is compared with BMD, degenerative change of disc, osteophyte grade of facet joint and promontory angle to reveal the association between these factors. RESULTS: A negative correlation is found between age and the amount of low back extensor muscle (p=0.001). The amount of low back extensor muscle in group A and group B was 60.3%+/-14.5% and 64.2%+/-9.3% respectively, thus showing a significantly smaller amount of low back extensor muscle in the osteoporotic vertebral fracture group (p=0.015). CONCLUSIONS: Fat infiltration of low back extensor muscle was increased in osteoporotic vertebral fracture patients. Therefore, fat infiltration of low back extensor muscle in an elderly person may be a risk factor of osteoporotic vertebral fracture.

Revision Hip Arthroplasty with a Cementless Femoral Stem / 대한고관절학회지

PURPOSE: To evaluate the clinical and radiographic results of patients who received revision total hip arthroplasty using cementless femoral stems. MATERIALS AND METHODS: This study included 26 patients who underwent revision total hip arthroplasty using a cementless femoral stems in our hospital, between Jan 2000 and May 2010, and were able to be evaluated in the final follow-up. The mean age was 63.8 years at the time of the revision surgery, and the follow up period was an average of 45 months. The causes of revision were aseptic loosening in 11 cases, periprosthetic fracture in 6 cases, femoral osteolysis in 6 cases, and infection in 3 cases. The radiologic results were evaluated in term of subsidence, loosening, and the stress shielding. The clinical results were evaluated by the Harris hip score and thigh pain. RESULTS: Harris hip score improved from 41.2 points preoperatively to 85.8 points at the final follow-up. There were 5 cases that complained of thigh pain at the last follow-up. Subsidence of femoral stem of more than 10 mm was observed in 3 cases. Stress shielding was noticed in 6 hips. The 3 grafted strut allografts were completely fused with the host bone. Complications included 2 cases of intraoperative periprosthetic fracture and 3 cases of dislocation. CONCLUSION: We obtained favorable clinical and radiologic outcomes in revision total hip arthroplasty using a cementless femoral stems. However, thigh pain and stress shielding resulted from the diameter of femoral stem being too large.

The Effectiveness of Ultrasound Guidance in Caudal Epidural Block

STUDY DESIGN: A prospective study. OBJECTIVES: To evaluate the effectiveness of ultrasound guidance in caudal epidural block and sonographic feature of sacral hiatus. SUMMARY OF LITERATURE REVIEW: High success rate of ultrasound-guided regional nerve block has been reported and recently, ultrasound-guided nerve block in spinal field has been introduced. MATERIALS AND METHODS: Ultrasound-guided caudal epidural block was performed in 48 patients with radiating pain to leg. Patient was placed in the prone position and sonographic image of sacral hiatus was obtained using linear probe. After measuring the intercornual distance, thickness of sacrococcygeal membrane and depth of sacral canal in transverse view, then the probe was rotated 90degrees to obtain the longitudinal view of the sacral hiatus. Under ultrasound guidance, a 21-gauge needle was inserted into the sacral hiatus in parallel with sacrum base. After contrast dye injection, needle placement was checked by the fluoroscopy and then medication was injected into the caudal epidural space. We investigated the change of radiating pain after caudal epidural block using visual analogue scale(VAS). RESULTS: The intercornual distance was mean 16.4+/-2.3mm, thickness of sacrococcygeal membrane was mean 2.8+/-0.9mm and depth of sacral hiatus was mean 2.6+/-0.9mm. There was 97.9% success rate of the caudal epidural block under ultrasound guidance. The mean VAS for radiating pain was improved from 7.5+/-0.7 before the block to 2.8+/-1.5 after the block. CONCLUSIONS: Ultrasound-guided caudal epidural block seems to provide good anatomical landmark of sacral hiatus and an effective tool with high success.

Retroperitoneal Hemorrhage after Thrombolysis in ST Elevation Myocardial Infarction / 영남의대학술지

Bleeding is the most common and serious complication of thrombolysis in ST elevation myocardial infarction. Most bleeding cases are associated with an intervention or operation, but spontaneous bleeding such as gastro-intestinal bleeding or intracranial hemorrhage can happen. This is a report on the case of a 76-year-old female patient with retroperitoneal hemorrhage due to spontaneous right colic artery branch bleeding after thrombolysis in ST elevation myocardial infarction.

Implicit Distinction of the Race Underlying the Perception of Faces by Event-Related fMRI

A few studies have shown that the function of fusiform face area is selectively involved in the perception of faces including a race difference. We investigated the neural substrates of the face-selective region called fusiform face area in the ventral occipital-temporal cortex and same-race memory superiority in the fusiform face area by the event-related fMRI. In our fMRI study, subjects (Oriental-Korean) performed the implicit distinction of the race while they consciously made familiar-judgments, regardless of whether they considered a face as Oriental-Korean or European-American. For race distinction as an implicit task, the fusiform face areas (FFA) and the right parahippocampal gyrus had a greater response to the presentation of Oriental-Korean faces than for the European-American faces, but in the conscious race distinction between Oriental-Korean and European-American faces, there was no significant difference observed in the FFA. These results suggest that different activation in the fusiform regions and right parahippocampal gyrus resulting from superiority of same-race memory could have implicitly taken place by the physiological processes of face recognition.

Implicit Distinction of the Race Underlying the Perception of Faces by Event-Related fMRI

A few studies have shown that the function of fusiform face area is selectively involved in the perception of faces including a race difference. We investigated the neural substrates of the face-selective region called fusiform face area in the ventral occipital-temporal cortex and same-race memory superiority in the fusiform face area by the event-related fMRI. In our fMRI study, subjects (Oriental-Korean) performed the implicit distinction of the race while they consciously made familiar-judgments, regardless of whether they considered a face as Oriental-Korean or European-American. For race distinction as an implicit task, the fusiform face areas (FFA) and the right parahippocampal gyrus had a greater response to the presentation of Oriental-Korean faces than for the European-American faces, but in the conscious race distinction between Oriental-Korean and European-American faces, there was no significant difference observed in the FFA. These results suggest that different activation in the fusiform regions and right parahippocampal gyrus resulting from superiority of same-race memory could have implicitly taken place by the physiological processes of face recognition.

A Case of Abdominal Pregnancy / 대한산부인과학회잡지

An abdominal pregnancy is defined as an ectopic pregnancy, which implants in the peritoneal cavity and can be classified as either primary or secondary. The incidence of abdominal pregnancy is increased after IVF or GIFT, induced abortion, endometriosis, and intrauterine devices may also contribute to an increased incidence. Early diagnosis and appropriate surgical management, regardless of stage of gestation, appear to be important in achieving good results. A case of early primary abdominal pregnancy which was implanted on the left uterosacral ligament. We report the case and brief review of literature.

The Relationship between Bone Mineral Density and Serum Lipid Profile in Postmenopausal Women / 대한산부인과학회잡지

OBJECTIVE: To assess the correlation of serum lipid profile with lumbar bone mineral density (BMD) in postmenopausal women and investigate whether serum lipid profile could be a risk factor of osteoporosis. METHODS: From 1995 to 2003, we retrospectively reviewed 231 postmenopausal women, who did not take any drugs affecting lipid or bone metabolism. The hysterectomized women or metabolic disease patients were excluded. We analyzed the relationship between serum lipid profile and other parameters in normal and osteopenic groups based on lumbar BMD. RESULTS: There was no significant relationship between serum lipid profile and lumbar BMD in univariate analysis (chi-squared test and Pearson correlation analysis). Lumbar BMD was correlated inversely with age (r=-0.355, por=160 mg/dL) LDL-C levels were 1.09 (95%CI: 0.58-2.05) and 1.10 (95%CI: 0.44-2.79), respectively, compared to normal (<130 mg/dL) LDL-C group. CONCLUSION: There was no correlation between serum lipid profile and lumbar BMD. Serum lipid profile may not be a risk factor of osteoporosis, however, a prospective study in a larger group, considered with multiple factors, will be required to get more proper conclusions.

Two Cases of Adenoma Malignum of the Uterine Cervix / 대한산부인과학회잡지

Adenoma malignum (minimal deviation adenocarcinoma) is a rare, well-differentiated form of cervical adenocarcinoma. This name is derived from the benign epithelial cell lining the glands. Despite its benign appearance, adenoma malignum have clinical malignant features. Because of its rarity and subtle histologic changes, it is quite difficult to diagnosis and may be missed. Adenoma malignum may carry a poor prognosis. We presented two cases of adenoma malignum of the uterine cervix with a brief review of related literatures.

The Clinical Significance of Oral Glucose Tolerance Test in Gestational Diabetes Mellitus / 대한산부인과학회잡지

OBJECTIVE: This study was performed to identify the clinical characteristics on the prevalence of gestational diabetes mellitus (GDM) related to risk factors and to assess the significance of screening test. METHODS: From Jan. 2000 to Dec. 2001, 513 women attending prenatal clinic were screened for GDM. Universal screening with 50 gm GTT were performed during 24-28th gestational weeks period. Women with 1 hour plasma glucose >or=140 mg/dl underwent 100 gm GTT for diagnosis of GDM. The patients were divided into high risk and control group. RESULTS: The overall incidence of GDM was 3.1%. Among high risk group and control group, the prevalence of positive screening tests were 28.9% vs 13.6% (P=0.001), and frequencies of abnormal 100 gm GTTs were 8.8% vs 0.6% (P=0.001), respectively. These rates were statistically significant. The significant risk factors were glucosuria, family history of DM and obesity (BMI >or=25). With increasing BMI, the prevalence of GDM was found to be significantly increased. CONCLUSION: The screening test of GDM would be preferable for all pregnant women rather than risk group only. Intensified management approach is needed for patients with glucosuria, family history of DM or obesity.

MRI Differential Diagnosis of Complete and Partial Tears of the Anterior Cruciate Ligament of the Knee: The Usefulness of Oblique Coronal T2-Weighted Image

PURPOSE: To assess the usefulness of T2-weighted oblique coronal MR imaging (T2OCI) in the differential diagnosis of complete and partial tears of the anterior cruciate ligament (ACL) of the knee. MATERIALS AND METHODS: Thirty-three patients with ACL tear (16 complete and 17 partial tears), comfirmed by arthroscopy, were included in this study. Conventional MR imaging and T2OCI were performed, and the findings were retrospectively reviewed by two radiologists in terms of continuity, shape, axis and internal signal intensity of the ligament. Each finding was tested if there were stastistically significant differences in its prevalence between partial and complete tears. The diagnostic accuracy of T2OCI and conventional MR imaging in the detection of partial and complete tears of the ACL were compared. RESULTS: Conventional MR imaging revealed no statistically significant finding for differential diagnosis of complete and partial ACL tears. The reliable and statistically significant (p<0.001) findings of T2OCI were complete discontinuity of the ligament in cases involving complete ACL tears (14 of 16 complete tears and 2 of 17 partial tears) and the preservation of the band form for partial ACL tears (2 of 16 complete tears and 15 of 17 partial tears). The accuracy of T2OCI and conventional MR imaging was 88% and 70%, respectively. CONCLUSION: When ACL injury is vague on conventional MR images, a modality which is more useful in the differential diagnosis of partial and complete tears of the ACL, and in predicting the site of a tear, is T2-weighted oblique coronal imaging.

Efficacy of Percutaneous Microwave Coagulation Therapy for Nodular Hepatic Tumor: A Preliminary Study

PURPOSE: Percutaneous microwave coagulation therapy (PMCT) uses a new energy source, microwave, in the treatment of solid neoplasms. We evaluated the efficacy of PMCT for nodular hepatic tumors in nine patients. MATERIALS AND METHODS: Between December 1998 and June 1999, we performed PMCT in six patients with hepatocellular carcinoma (HCC), two with one and three metastatic nodules each from colon cancer, and one with adenomatous hyperplasia. Four patients were female and five were male, and their age ranged between 44 and 71 (mean, 58.8) years. Under sonographic guidance a 14-gauge guiding needle was inserted percutaneously toward the lesion, and within it a needle electrode was precisely positioned. Microwave 2450MHz in frequency and with 60 or 80 watt emission was generated for 80~90 seconds. We evaluated the ultrasound findings obtained during the procedure, pre-PMCT and follow-up CT images, changes in tumor marker(AFP or CA19-9) levels and the results of liver function tests, and complications arising during the six-month period following PMCT. RESULTS: Immediately after microwave emission, characteristic hyperechogenicity appeared on the realtime sonogram. Two patients with HCC underwent CT before PMCT, and typical enhancement during the arterial phase and washout during the portovenous phase was observed. In one patient, two metastatic lesions from colon cancer showed delayed enhancement on pre-PMCT CT. Initial follow-up CT, performed between 1 and 4 weeks after the PMCT procedure, showed that eight lesions-including two HCCs which were highly enhanced on CT before PMCT-showed no contrast enhancement, and three others showed delayed enhancement. Two of the eight lesions which showed no contrast enhancement at initial follow-up CT were markedly decreased in size (from 2.9 and 4.0 cm to 1.0 and 2.0 cm, respectively) at subseqent follow-up 3 months and 6 months later, respectively. One of the three lesions showing delayed enhancement had increased in size from 4.1 to 5.5 cm at subsequent follow-up CT, 2 months later. Serum AFP or CA19-9 levels decreased in four of six patients (66.7%) who were followed up for 6 months. Transient elevation of aspartate aminotransferase(AST) levels were noted in all patients. PMCT-related complications included intrahepatic arterioportal shunt in two patients, pleural effusion in one, skin burn in one, intraperitoneal hemorrhage in one, and mild fever, abdominal pain and nausea in seven. No complications were serious, however. CONCLUSION: Our preliminary experiences suggest that PMCT is a safe and effective treatment modality for nodular hepatic tumors.

Primary Lymphoma of the Colon: Radiologic and Pathologic Findings

Compared with the stomach and small intestine, the colon and rectum are uncommon sites of lymphomatous involvement. Primary colorectal lymphoma is diagnosed when the lesion is confined to the colorectal area and regional lymph nodes, without involvement of other organs including the upper gastrointestinal tract, bone marrow, and distant lymph nodes. The radiologic appearance of primary lymphoma of the stomach and small bowel is well known, but in cases involving the colorectal area, this is not so. In this article, we categorize and illustrate the radiologic manifestations of primary colorectal lymphoma according to the findings of double-contrast barium enema and CT images, and describe the pathologic findings.

Bronchial Brushing and Bronchial Washing for Diagnosis of Central Lung Cancer / 결핵

BACKGROUND: Forceps biopsy, bronchial brushing, and bronchial washing are used in conjuction with bronchoscopy to provide specimens for histologic and cytologic analysis in patients with suspected lung cancer. This study was performed to evaluate how many times brushing should be done and how much fluid should be used during bronchial washing for increasing diagnostic yield, and to evaluate which combination of these procedures gives the highest diagnostic yield. METHODS: Forty patients, with suspected lung cancer, who had bronchoscopically visible lesions were enrolled in this prospective study. During one bronchoscopic examination four forceps biopsies, four bronchial brushings, and bronchial washing were done in all patients. The patients were divided into four groups by the amount of normal saline used for bronchial washing; group I, 10 ml; group II, 20ml; group III 30ml, and group IV, 40ml. We analyzed the results in 36 patients confirmed as lung cancer. RESULTS: The diagnostic sensitivity of bronchial washing before and after forceps biopsy and bronchial brushing were 36% and 28%, respectively. The cumulative diagnostic sensitivity of bronchial washing were 47% and significantly higher than that of bronchial washing before or after forceps biopsy and bronchial brushing (p < 0.05). The diagnostic sensitivity of bronchial washing with saline of 30ml was significantly higher than that of bronchial washing with saline of 10ml or 20ml (p < 0.05). The diagnostic sensitivity of the first brushing was 75%, the second brushing 78%, the third brushing 83%, and the fourth brushing 67%. With repeated brushing up to three times, the diagnostic sensitivity increased to 92% (p<0.05). However, inclusion of the fourth brushing did not give a further increase of the diagnostic sensitivity. The diagnostic sensitivity of forceps biopsy was 86%. The diagnostic sensitivities of forceps biopsy by the type of bronchial lesion were as follows: tumor, 88%; infliltration, 67%; infiltration with nodularity, 80%; and collapse, 100%. The combination of forceps biopsy and bronchial washing gave a diagnostic sensitivity of 89%. The diagnostic sensitivity of combining forceps biopsy with bronchial brushing was 97%. Addition of bronchial washing did not increase the diagnostic yield over forceps biopsy and bronchial brushing. CONCLUSION: In patients with central lung cancer, forceps biopsies and repeated brushings up to three times should be done for maximal diagnostic yield.

Microwave Tissue Coagulation: Effects of Power and Treatment Time on Coagulation size

PURPOSE: To determine the effects of power and coagulation time on lesion size of ex-vivo bovine liver using microwaves. MATERIALS AND METHODS: Six bovine livers were divided into two groups(first group: 30W output, secondgroup: 60W output) and microwave coagulation was performed for 30, 60, and 120 sec. thermal injury site was thenobserved by means of sonography, and the maximal transverse diameter of the echo-change portion after microwave coagulation was measured. On the section of specimen, maximal transverse diameters of the thermal injury site weremeasured by gross inspection and compared with the result of sonographic measurement. RESULTS: Maximal transversediameters of hyperechoic lesions of the first group, as seen on sonography were 8.3 mm, 12.2mm, and 15.6mm, andthe maximal transverse diameters of thermal injury sites on gross specimens were 9.1mm, 12.0mm, and 15.1mm,respectively. Maximal transverse diameters of hyperechoic lesions of the second group, as seen on sonography, were12.1 mm, 17.4 mm, and 21.2 mm and maximal transverse diameters of thermal injury sites on gross specimens were13.2 mm, 16.0 mm, and 20.0 mm, respectively. Statistically maximal transverse diameters of hyperechoic lesions, asseen on sonography, correlated closely with the gross findings of maximal transverse diameters of thermal injurysites(p<0.05). CONCLUSION: Maximal transverse diameters of thermal injury sites were significantly increased asthe output of the microwave coagulator and the duration of coagulation time increased(p<0.05).

The Role of Bronchoscopy in Determining the Etiology of Pleural Effusion / 결핵

BACKGROUND: Little information is available concerning the value of bronchoscopy in patients with a lymphocytic exudative pleural effusion in which percutaneous pleural biopsy have been regarded as cornerstone in investigating the etiology. Recenfly, a few reports suggest that bronchoscopy may be more effective diagnostic method in patients with unexplained pleural effusion accompanied by hemoptysis or other roentgenographic abnormalities, such as mass, infiltrate, atelectasis. METHOD: After initial examinations of sputum and pleural fluid through thoracentesis in 112 patients(male 75 cases, female 37 cases, mean age 53.2 years) who were admitted for evaluation of the cause of pleural effusion, we performed bronchoscopy and closed pleural biopsy in most patients with undiagnosed lymphocytic exudate and compared the diagnostic yield of both invasive methods according to hemoptysis or other roentgenographic abnormalities, and investigated the sole diagnostic contribution of bronchoscopy. RESULTS: Tuberculosis(57 cases, 51%) was the most common cause of pleural effusion Percutaneous pleural biopsy showed more diagnostic yield than bronchoscopy regardless of presence or absence of other clinical or radiologic abnormalities. In 25 cases with unknown etiology after pleural biopsy, additional diagnostic yield by bronchoscopy was 36% (4/11) in patients with associated features and only 7% (1/14) with lone effusion, and, as the sole mean for diagnsosis in all patients with pleural effusion, was only 4.5% (5/12) Condusion: In a region of high prevalence of tuberculosis as a cause of pleural effusion, percutaneous pleural biospy is more effective method when invasive method is required for confirmative diagnosis of unexplained lymphocytic exudative pleural effusion, and bronchoscopy is unlikely to aid in the diagnosis of lone pleural effusion.

MR Imaging findings of Diffuse Axonal Injury: Comparison of T2*-weighted Gradient Images and T1- andT2-weighted Spin-Echo Images

PURPOSE: To compare T2*-weighted images with spin-echo T1- and turbo spin-echo (TSE) T2-weighted images inpatients with diffuse axonal injury(DAI) MATERIALS AND METHODS: Using a 1.0T MR unit, SE T1-, TSE T2-, and andFLASH T2*-weighted images were obtained from 69 patients with a history of head trauma. In 18 MR images of 17patients with imaging findings of DAI, T2*-weighted images were retrospectively compared with SE T1-and TSET2-weighted images. The interval between trauma and MR scan varied from 5 days to 24 (mean, 11) months. Focusingon the number of lesions, and their location and signal intensity, as weel as associated findings, three imageswere simultaueously evaluated. RESULTS: In 18 MR images of 17 patients with MR imaging findings of DAI, 21lesions were detected on T1-weighted images, 28 on TSE T2-weighted images, and 70 on T2*-weighted images; the lastof these revealed all lesions detected on the other two. Most lesions were hypointense on T1-weightedimages(17/21), hyperintense on TSE T2-weighted (21/28), and hypointense on T2*-weighted (63/70). Common locationsfor DAI were the frontal lobe(n=35) and corpus callosum (n=22). Associated brain injuries were cortical contusion(n=5), brainstem injury (n=3), deep gray matter injury (n=2), and subdural hematoma (n=1). CONCLUSION: Inpatients with DAI. T2*-weighted images can detect more lesions and associated petechial hemorrhage than can TSET2-weighted images. This modality is thus useful for the evaluation of patients with head trauma.