PubMed Health⌕ Search

Biomedical subjects

Ming-Huei Sheu

Publications and source records attributed to Ming-Huei Sheu.

14 recordsLinked to original sources
PubMed2006

Anatomic characteristics of the left atrial isthmus in patients with atrial fibrillation: lessons from computed tomographic images.

INTRODUCTION: Left atrial (LA) isthmus ablation was reported to improve the success rate of catheter ablation of paroxysmal atrial fibrillation (AF). LA isthmus ablation could also cure a subset of LA flutter. Therefore, understanding the anatomy of the LA isthmus is important for performing the ablation effectively. METHODS AND RESULTS: Group I included 45 patients (40 male, mean age = 50 +/- 13 years) with paroxysmal AF who underwent catheter ablation. Group II included 45 patients (37 male, mean age = 54 +/- 10 years) without a history of AF. They underwent a 16-slice multidetector computed tomography (MDCT) scan to delineate the LA structures before the ablation procedure. The average length of the LA isthmus was longer in group I than in group II (lateral isthmus: 3.30 +/- 0.68 vs 2.71 +/- 0.60 cm, P < 0.001; medial isthmus: 5.12 +/- 0.94 vs 4.45 +/- 0.63 cm, P < 0.001), and morphological patterns of lateral and medial isthmus were similar between groups. In addition, the average depth of lateral isthmus was similar between groups (0.62 +/- 0.32 vs 0.55 +/- 0.33 cm, P = 0.41), but the average depth of medial isthmus was larger in group I than in group II (0.60 +/- 0.32 vs 0.44 +/- 0.25 cm, P = 0.01). The medial isthmus had more ridges, as compared to the lateral isthmus (13% vs 0%, P = 0.026). Furthermore, the distances between esophagus and lateral isthmus were longer in group I than in group II (at the middle of isthmus and mitral annulus level: 21.0 +/- 4.8 vs 18.4 +/- 6.0 mm, P < 0.001; and 37.1 +/- 5.7 vs 29.6 +/- 8.1 mm, P < 0.001, respectively). CONCLUSION: The LA isthmus was longer in the AF patients. The morphology of the isthmus was variable. Compared with the lateral isthmus, the medial isthmus was longer and had more ridges. A peculiar configuration of the isthmus provided by CT images could influence the ablation strategy.

Anthropometry↗
PubMed2006

Morphological changes of the left atrial appendage after catheter ablation of atrial fibrillation.

INTRODUCTION: The left atrial appendage (LAA) has been proven to be the most important site of thrombus formation in patients with atrial fibrillation (AF). However, the information regarding the morphometric alteration of the LAA related to the outcome of AF ablation is still lacking. Thus, we evaluated the long-term changes of the LAA morphology in patients undergoing catheter ablation of AF using magnetic resonance angiography (MRA). METHODS AND RESULTS: Group 1 included 15 controls without any AF history. Group 2 included 40 patients with drug-refractory paroxysmal AF. They were divided into two subgroups: group 2a included 30 patients without AF recurrence after pulmonary vein (PV) ablation. Group 2b included 10 patients with late recurrence of AF. The LAA morphology before and after (20 +/- 11 months) ablation was evaluated by three-dimensional MRA. The group 2 patients had a larger baseline LAA size (including the LAA orifice, neck, and length) and less eccentric LAA orifice and neck. After the AF ablation, there was a significant reduction in the LAA size in the group 2a patients, and the morphology of the LAA neck became more eccentric during the follow-up period. In group 2b, the LAA size increased and no significant change in the eccentricity of the orifice and neck could be noted. CONCLUSIONS: The morphometric remodeling of the LAA in the AF patients could be reversed after a successful ablation of the AF. Progressive dilation of the LAA was noted in the patients with AF recurrence. These structural changes in the LAA may play a role in reducing the potential risk of cerebrovascular accidents.

Atrial Appendage↗
PubMed2006

Electron beam computed tomography evidence of aortic calcification as an independent determinant of coronary artery calcification.

BACKGROUND: Imaging of the aorta has received less attention than imaging of the coronary beds, despite the possible link between aortic and coronary artery disease (CAD). Electron beam computed tomography (EBCT) with 100 ms scanning speed can eliminate pulsation-related motion artifacts. The goals of this study were to evaluate EBCT-detected subclinical atherosclerosis over the whole aorta as in routine abdominal and thoracic CT scans and analyze whether or not the measurements of aortic calcification (AC) can independently predict the presence of coronary artery calcification (CAC), which is a surrogate marker of CAD. METHODS: A consecutive series of 196 adults (male:female, 127:69; mean age, 65.9 +/- 10.5 years) were enrolled for EBCT examinations of the coronary arteries and whole aorta. CAC and AC were calculated by the Agatston method. Major cardiovascular risk factors were also recorded. RESULTS: The greatest amount of AC was seen at the abdominal aorta, followed by the descending aortic arch, thoracic aorta, and ascending aorta. Total AC was significantly correlated with CAC (r = 0.51, p < 0.001). After adjustment for major cardiovascular risk factors of age, gender, diabetes, hypertension, hypercholesterolemia, and family history, the three independent significant determinants of CAC were abdominal AC, thoracic descending AC, and male gender (model r2 = 0.495, p < 0.001). For receiver operating characteristic analysis in predicting the presence of CAC, the threshold of descending AC was 11, with 68.3% sensitivity and 75.0% specificity. The optimal threshold of abdominal AC was 123, with 74.1% sensitivity and 67.9% specificity. CONCLUSION: AC values in different portions of the aorta are independent predictors for the presence of CAC.

Adult↗
PubMed2006

Morphologic characteristics of the left atrial appendage, roof, and septum: implications for the ablation of atrial fibrillation.

INTRODUCTION: The left atrium (LA) ablation in different regions, including LA appendage (LAA), LA roof, and LA septum, has recently been proposed to improve the success rate of treating patients with atrial fibrillation (AF). The purpose of this study was to investigate the anatomy of LAA, LA roof, and LA septum, using computed tomography (CT). METHODS AND RESULTS: Multidetector CT scan was used to depict the LA in 47 patients with drug-refractory paroxysmal AF (39 males, age = 50 +/- 12 years) and 49 control subjects (34 males, age = 54 +/- 11 years). The area of LAA orifice, neck, and the length of roof line were greater in AF group than in control subjects. Three types of LAA locations and two types of LAA ridges were observed. Higher incidence of inferior LAA was noted in AF patients. The different morphologies of LA roof were described. Roof pouches were revealed in 15% of AF and 14% of controls. Moreover, we found septal ridge in 32% of AF and 23% of controls. CONCLUSIONS: Considerable variations of LAA and LA roof morphologies were demonstrated. Peculiar structures, including roof pouches and septal ridges, were delineated by CT imaging. These findings were important for determining the strategy of AF ablation and avoiding the procedure-related complications.

Adult↗
PubMed2005

Bowel preparation of outpatients for intravenous urography: efficacy of castor oil versus bisacodyl.

The purpose of this study was to compare the efficacy of two laxatives, castor oil and bisacodyl, in the routine bowel preparation of outpatients for intravenous urography (IVU). We used castor oil in patients undergoing IVU for 1 month, and then used bisacodyl in patients undergoing IVU for another month. Two uroradiologists, unaware of the method of bowel preparation, reviewed the standard radiographs and graded the residue in the large bowel and the clearness of the opacified urinary collecting system. In total, 71 consecutive outpatients received castor oil, and 84 received bisacodyl. For the castor oil group, grades from the two uroradiologists did not differ in terms of fecal residue on plain abdominal images (p = 0.54), and visualization of the urinary system on the left (p = 0.36) and right sides (p = 0.63). Findings were similar for bisacodyl recipients (p = 0.11, 0.59, and 0.32, respectively). When the laxative effect of the two agents was compared, we found no difference in the grading of fecal residue on plain abdominal images (p = 0.14), or in visualization of the urinary system on the left (p = 0.31) and right sides (p = 0.98). In conclusion, we observed no difference in laxative efficacy between castor oil and bisacodyl; thus, bisacodyl may be a useful alternative for bowel preparation before IVU.

Bisacodyl↗
PubMed2005

Bicycle-handlebar hernia: a rare traumatic abdominal wall hernia.

Handlebar hernia is a rare, traumatic, abdominal wall hernia caused by high-velocity direct trauma. It involves disruption of the abdominal wall muscles, with bowel loop herniated through the defect in the abdominal wall, and may have major or even lethal complications. We report a case of bicycle-handlebar hernia in a 9-year-old boy who had all layers of his abdominal wall disrupted by a fall when bicycling; however, his skin and intra-abdominal organs were completely intact. Computed tomography demonstrated subcutaneous intestinal loops protruding through the rent. Primary repair was performed, and his postoperative course was uneventful.

Abdominal Injuries↗
PubMed2005

Demonstration of large bladder diverticulum on bone scan.

A 74-year-old man underwent low anterior resection for rectal cancer. Technetium-99m methylene diphosphonate (MDP) bone scanning was performed as part of the patient's postoperative follow-up study. Scans revealed an area of increased tracer uptake in the left hemipelvis. Coronal single-photon emission computed tomography and caudal images clearly separated the lesion from the skeletal structures. Transverse magnetic resonance images showed a large diverticulum originating from the left lateral wall of the bladder. The pelvic findings on the bone scan were the result of tracer retained within this diverticulum.

Aged↗
PubMed2004

Urolithiasis in pregnancy.

BACKGROUND: The aim of this study was to review our experience in the diagnosis and management of urolithiasis in pregnant women, and to discuss safety, appropriate diagnostic tools and treatment modalities with review of literatures. METHODS: Nine women with pregnancy proved to have urolithiasis were included in this study. The diagnosis was made according to their symptoms and signs, and ultrasonographic findings. Conservative treatment with hydration, analgesics and antibiotics was applied initially, followed by some minimally invasive procedures, including percutaneous nephrostomy (PCN), double J (DBJ) stenting and ureterorenoscopy (URS), if initial treatment failed. RESULTS: All patients received conservative treatment at first, and 4 patients got well till delivery, another 5 patients needed further minimally invasive procedures; 1 of them received DBJ stenting, another 1 received PCN first and changed to DBJ stenting. The remaining 3 patients were treated by ureterorenoscopy with stone manipulation. All these 5 patiens had full-term delivery without obstetric sequela, except 1 patient who received left salpingoophrectomy due to left ovarian abscess. CONCLUSIONS: During pregnancy, urolithiasis is a diagnostic and therapeutic challenge. Clinical symptoms and signs are most important in establishing diagnosis, and ultrasound examination adds accuracy. Minimally invasive procedures (such as PCN, DBJ stenting, URS) can facilitate the successful management of patients requiring further intervention due to failure of conservative treatment.

Adult↗
PubMed2003

Skew ocular deviation: a catastrophic sign on MRI of fetal glioblastoma.

CASE REPORT: We report the prenatal observation of fetal ocular skew deviation in a case of a glioblastoma found prenatally at 33 weeks' gestation by MRI. The fetal MRI, obtained by half-Fourier single-shot turbo spin echo (HASTE) pulse sequences, showed a tumor (80 mm in maximum diameter) in the right deep cerebral hemisphere with extension to the mid-cranial fossa and tentorial hiatus in addition to severe hydrocephalus. On coronal MR images a vertical dysconjugated gaze was recognized. One week after the MRI, frequent delayed deceleration prompted an emergency cesarean section. The baby was born with left hemiparesis and central neurogenic hyperventilation, which evolved into decerebrate rigidity and apneustic breathing within 2 h. Post-mortem examination revealed a glioblastoma in the right deep hemisphere, a tumor with brain stem involvement, and transtentorial herniation. CONCLUSIONS: We suggest, therefore, that recognition of ocular skew deviation on fetal MR images would indicate brain stem involvement and poor postnatal prognosis. Early recognition of the catastrophic sign would lead to proper management.

Adult↗
PubMedDate not supplied

Initial experience using magnetic resonance imaging in prenatal diagnosis of osteogenesis imperfecta type II: a case report.

We report a fetus with osteogenesis imperfecta (OI) first diagnosed by ultrasound in routine prenatal examination and further evaluated by magnetic resonance imaging (MRI). Fetal MRI was undertaken with a 1.5-T magnet using a body-phased array coil and an ultrafast imaging technique, half-Fourier single-shot turbo spin-echo (HASTE). Radiological examination shortly after birth and postmortem examination confirmed the prenatal diagnosis. In this case, fetal MRI provided excellent spatial and tissue resolution with multiplanar display. It revealed additional diagnostic information and improved imaging conspicuity. MRI complemented sonography for further differentiating clinical and sonographic findings.

Adult↗
PubMedDate not supplied

Magnetic resonance imaging of pregnancy luteoma.

We present the magnetic resonance (MR) imaging findings of pregnancy luteoma in an asymptomatic woman at 32 weeks of gestation. MR imaging with a half-Fourier, single-shot, turbo spin-echo sequence showed multilocular cystic masses with thickened internal septa in bilateral adnexa. The MR findings were similar to those of other cystic tumors or tumor-like lesions of the ovary.

Adnexa Uteri↗