Biomedical subjects

Lai-Chu See

Publications and source records attributed to Lai-Chu See.

46 records · Page 3Linked to original sources

PubMed2003

Contrast material extravasation on contrast-enhanced helical computed tomographic scan of blunt abdominal trauma: its significance on the choice, time, and outcome of treatment.

BACKGROUND: Contrast-enhanced helical computed tomographic (CT) scan of blunt abdominal trauma is valuable for detecting contrast material extravasation (CME). The aims of this study were to determine its significance and investigate factors associated with the choice, time, and outcome of management. METHODS: CT scans of 32 consecutive trauma patients who had CME were reviewed for the sources of CME, types of CME, flat inferior vena cava, and multiple abdominal injuries. The medical records were reviewed for demographics, systolic blood pressure, Injury Severity Score (ISS), choice of management, time interval between CT scan and intervention, and outcome of intervention. RESULTS: Systolic blood pressure < 100 mm Hg was the most important factor (p = 0.0064) that failed observational therapy. When proceeding to intervention treatment, patients with a flat inferior vena cava (1.6 +/- 1.1 hours) had a significantly shorter time interval between CT scan examination and intervention when compared with those with a normal cava (10.9 +/- 16.0 hours) ( p= 0.0124). The mortality rate after intervention treatment was 18.8%. High ISS, uncontained CME in the extraperitoneum, and multiple abdominal injuries were important risk factors. After adjusted for ISS and multiple abdominal injuries, the risk of dying from extraperitoneal CME remained significant when compared with intraperitoneal CME (adjusted odds ratio, 82.26; 95% confidence interval, 1.06-6,363.17). CONCLUSION: Termination of observational therapy was appropriate for trauma patients who had CME and systolic blood pressure < 100 mm Hg. The coexistence of a flat inferior vena cava and CME was associated with early intervention treatment. Despite early intervention, the mortality rate was 18.8%. High ISS and multiple abdominal injuries were important factors, but the risk of dying from uncontained extraperitoneal CME was 82 times the risk of dying from intraperitoneal CME.

Abdominal Injuries↗

PubMed2003

Delayed (18)F-FDG PET for detection of paraaortic lymph node metastases in cervical cancer patients.

UNLABELLED: This prospective study investigated the usefulness of dual-phase (18)F-FDG PET scans (40 min and 3 h) in detecting paraaortic lymph node (PALN) metastasis for cervical cancer. METHODS: One hundred four consecutive cervical cancer patients (International Federation of Gynecology and Obstetrics staging Ib-IVb, recurrent or persistent tumors) were included. All patients received a whole-body (18)F-FDG PET scan at 40 min and an additional scan from the T11 level to the inguinal region at 3 h after injection of 370 MBq (18)F-FDG. The maximum standardized uptake value (SUV) and retention index (RI [%], obtained by subtracting the normalized SUV value obtained at 40 min from that at 3 h) of the lesions were determined. RESULTS: In all, 38 of the 104 patients were confirmed to have PALN metastases. For 31 patients (81.6%) with 13 upper (L1-L2 level) and 30 lower (L3-L4 level) PALNs, these metastases were detected with the 40-min scan. In addition, for 7 patients (18.4%) with 7 lower PALNs, metastases were found with the 3-h scan (RI = 12.6%). Two patients (3.0%) had 2 false-positive lesions initially (40 min) but were classified as benign with the 3-h scan. The sensitivity, specificity, and accuracy of (18)F-FDG PET scans at 40 min were 81.6%, 97.0%, and 91.3%, respectively. These quantities were all 100% when both the 40-min and 3-h scans were taken together. Eight patients (21.1%) had their treatment planning changed. We divided the 38 patients into 2 subgroups. Subgroup A included those with either only upper or only lower PALN metastases, and subgroup B included those with both upper and lower PALN metastases. In subgroup A, the SUV values were greater in the upper than in the lower PALNs in both the 40-min and 3-h images (P = 0.077). In subgroup B, there was no significant difference of SUV values between upper and lower PALNs in the 40-min (P = 0.433) and 3-h (P = 0.937) images. CONCLUSION: Our results showed that an additional 3-h scan is helpful for PALN detection of cervical cancer patients. A delayed image (3 h) is especially useful for lower PALN metastases.

Adult↗

PubMed2003

Propofol inhibits neuronal firing activities in the caudal ventrolateral medulla.

BACKGROUND: Propofol is a potent intravenous anesthetic. The action of propofol on the medullary depressor area, the caudal ventrolateral medulla (CVLM), has not been well established. We therefore performed extracellular recordings to study the neuronal activity of the CVLM in cats before and after intravenous propofol administration, to investigate its influence on neuronal firings. METHODS: Experiments were performed on 31 cats anaesthetized with a mixture of alpha-chloralose and urethane administered intraperitoneally. Mean systemic arterial pressure, heart rate, and the neuronal firing (NF) rate were continuously recorded before and after intravenous injection of a single dose of 2 mg x kg(-1) propofol or separate supplemental doses of 1, 2, and 4 mg x kg(-1) propofol until those parameters had returned to the premedication level. RESULTS: Propofol dose-dependently and reversibly inhibited the NF rate after the supplemental doses of 1, 2, and 4 mg x kg(-1) propofol. The control NF rate of 17.9 +/- 8.6 Hz was depressed to 15.8 +/- 8.5 Hz after the first dose of propofol (p < 0.05 vs. the control), and was further depressed to 12.8 +/- 8.3 Hz (p < 0.05 vs. the control) and 10.0 +/- 7.9 Hz (p < 0.05 vs. the control) after the second and the third doses of propofol, respectively. CONCLUSION: The dose-dependent inhibition of the spontaneous neuronal firing rate is the main pharmacological action of propofol in the caudal ventrolateral medulla of cats.

Anesthetics, Intravenous↗

PubMed2002

Computerized tomography characteristics that differentiate angiomyolipomas from liposarcomas in the perinephric space.

PURPOSE: We performed a retrospective study to determine computerized tomography (CT) findings associated with perinephric angiomyolipomas or perinephric liposarcomas. MATERIALS AND METHODS: During the last 7 years 6 patients with perinephric angiomyolipoma and 12 with perinephric liposarcoma were seen at our hospital. Two radiologists who were blinded to the pathological diagnosis retrospectively evaluated the CT characteristics of perinephric angiomyolipoma and perinephric liposarcoma. The relationship of each CT characteristic with tumor type was compared using Fisher's exact test. RESULTS: The CT characteristics of perinephric angiomyolipoma were intratumoral linear vascularity (p = 0.001), aneurysmal dilatation (p = 0.025), bridging vessel sign (p = 0.005), hematoma (p = 0.025), beak sign (p = 0.001) and discrete intrarenal fatty tumors (p = 0.025). The CT characteristic of perinephric liposarcoma was a nonfatty soft tissue mass (p = 0.005). There was no significant difference in the presence of calcifications in both groups. CONCLUSIONS: This retrospective study suggests that analysis of CT characteristics (linear vascularity, aneurysmal dilatation, bridging vessel sign, hematoma, beak sign and discrete intrarenal fatty tumors) may help to differentiate perinephric angiomyolipoma from perinephric liposarcoma.

Adult↗

PubMed2002

Candida peritonitis due to peptic ulcer perforation: incidence rate, risk factors, prognosis and susceptibility to fluconazole and amphotericin B.

Sixty-two cases of peritonitis due to peptic ulcer perforation were diagnosed between January 2000 and December 2000. Of these 62 cases, 23 isolates of Candida in 23 cases (CP) were cultured from peritoneal fluid. Cultures of peritoneal fluid of 10 (BP) of the remaining 39 cases was positive for bacteria only. Cultures of peritoneal fluid of the remaining 29 cases was negative. Comparison of CP, BP and culture-negative cases did not reveal any significant risk factor. Of the 23 Candida isolates, the Candida species and 48-h MICs of fluconazole and amphotericin B (mean, range ug/ml) were C. albicans 18 (0.688, 0.125-1.0; 0.297, 0.031-0.5), C. glabrata 3 (0.542, 0.125-1.0; 0.25, 0.125-0.5), C. tropicalis 1 (0.25; 0.5), C. intermedia 1 (1.0; 0.125) respectively. Mortality rates of CP, BP and culture-negative peritonitis due to infection were 5/23(21.7%), 0/10 and 1/29(3.4%) respectively. Without effective antifungal therapy, the mortality rate of CP was not low.

Adult↗

PubMed2002

Formation of independently revascularized bowel segments using the rectus abdominis muscle flap: a rat model for jejunal prefabrication.

Reconstruction of the pharyngoesophagus with free jejunal transfer is a major challenge when recipient neck vessels are absent because of previous surgery or irradiation. In such instances, jejunal transfer using a muscle flap as a "vascular carrier" may be a problem-solving alternative. Pretransfer vascularization of the jejunum is achieved by wrapping the muscle flap around the small bowel segment. After a short staging period, the mesenteric pedicle is divided and the bowel segment is transferred up to the neck based on its new blood supply. The objectives of this study were to develop an animal model for prefabricating independently revascularized jejunal segments using the rectus abdominis muscle flap and to determine the minimal time required for independent bowel survival. Twenty-four mature (500-g to 700-g) rats were divided into six experimental groups of four animals each. In each animal, a 1.5-cm segment of proximal jejunum was isolated on two jejunal arteries and wrapped with a superior pedicled rectus abdominis muscle flap. To determine the time of neovascular takeover, the mesenteric pedicles were ligated on postoperative day 2 (group I), day 3 (group II), day 4 (group III), day 5 (group IV), day 6 (group V), and day 7 (group VI). At the time of pedicle ligation, the composite flap was transposed to a new subcutaneous position. Viability of bowel was assessed according to gross appearance and histologic examination 48 hours after transfer. Complete survival of revascularized jejunum in 11 of 12 animals was obtained after pedicle ligation on postoperative day 5 and beyond (p < 0.0001, Fisher's exact test). These bowel segments demonstrated luminal patency, intact pink mucosa, mucus production, and visible peristalsis. Histologic examination showed healthy intestinal epithelium and tissue integration along the serosa-muscle interphase. In contrast, pedicle ligation on day 4 and earlier resulted in varying degrees of bowel necrosis characterized by flattening or ulceration of mucosa (day 4), mucosal sloughing and necrosis of mural musculature (day 3), and complete loss of bowel architecture with lumen obliteration (day 2). These findings suggest that jejunal segments may be independently revascularized with the rectus abdominis muscle flap in the rat model. Complete survival and gross normal bowel function may be obtained without mesenteric perfusion after a minimal time of 5 days.

Abdominal Muscles↗

PubMedDate not supplied

Propofol ensures a more stable A-line ARX index than thiopental during intubation.

BACKGROUND: The A-line autoregressive modelling with exogenous input index (AAI) is a new method of assessing depth of anesthesia. We examined the effects of tracheal intubation on the AAI and hemodynamics during induction of anesthesia with propofol compared with thiopental in patients aged over 50 yr. METHODS: 40 patients scheduled for a laminectomy, posterior spinal fusion, vertebroplasty, or total hip replacement, ASA physical status I or II and aged over 50 yr, were randomly divided into two groups. Thiopental 5 mg.kg(-1) iv, fentanyl 2.5 microg.kg(-1) iv, and rocuronium 0.7 mg.kg(-1) iv were used in the thiopental group (n = 20) for anesthetic induction; the same protocol was used in the propofol group (n = 20) except that 2 mg.kg(-1) propofol iv was given instead of thiopental. The AAI, non-invasive blood pressure, and heart rate were measured every minute before induction for three minutes, at 1.5 min post-induction, and then each minute post-intubation for eight minutes. RESULTS: The AAI increased significantly at one and two minutes after intubation in the thiopental group (to 56.5 +/- 18.6 at 1 min and 44.7 +/- 18.7 at 2 min after intubation vs 19.9 +/- 7.5 at 1.5 min after induction; P < 0.05). Thereafter, AAI values gradually decreased three minutes after intubation. The AAI was inhibited continuously after intubation in the propofol group, and no significant elevation was seen. CONCLUSION: Our results, using the AAI to monitor anesthetic depth during induction and tracheal intubation, suggest that at equipotent doses propofol provided a more stable level of anesthesia than did thiopental.

Anesthetics, Intravenous↗

PubMedDate not supplied

Selection of scleral buckling for primary retinal detachment.

PURPOSE: Rhegmatogenous retinal detachment (RRD) may be caused by a flap tear or by an atrophic hole along the lattice degeneration. The aim of this study was to see whether different types of scleral buckling could achieve comparable reattachment rates in eyes with specific types of RRD. PATIENTS AND METHODS: 128 eyes with RRD were assigned to receive 1 of 3 buckling procedures according to the following guidelines: retinal detachments caused by flap tears were treated with radial segmental buckling; retinal detachments caused by atrophic holes with limited lattice degeneration were treated with circumferential segmental buckling, and retinal detachments caused by multiple breaks with extensive lattice degeneration were treated with encircling buckling. RESULTS: 56 eyes received radial segmental buckling, 36 eyes received circumferential segmental buckling, and 36 eyes received encircling buckling. The reattachment rates in these three groups were 83.9, 86.1, and 88.9%, respectively (no statistically significant difference). The visual outcomes were comparable in all groups. Younger age, an increased requirement for subretinal fluid drainage, longer operation time, and myopic shift were noted in the encircling group. CONCLUSIONS: Comparable reattachment rates could be achieved in all three groups according to our guidelines. Segmental buckling is appropriate for two thirds of RRD in this study and has fewer complications than encircling buckling. Every retinal detachment behaves differently and should be subjected to its optimal buckling procedure to achieve the best results and to avoid unnecessary operative complications.

Adolescent↗

PubMedDate not supplied

Unambiguous comparison of juvenile and senile rhegmatogenous retinal detachment.

BACKGROUND AND OBJECTIVE: To investigate whether age is a prognostic factor in rhegmatogenous retinal detachment (RRD). PATIENTS AND METHODS: The patient population was divided into two groups according to age at onset of RRD (juvenile R RD = younger than18 years and senile RRD = 65 years and older). The juvenile RRD group consisted of 35 patients and the senile RRD group consisted of 39 patients. RESULTS: There were statistically higher incidences of male patients, trauma, subretinal fibrosis, and myopia in the juvenile RRD group compared withthe senile RRD group. In addition, there were statistical differences in the break characteristics, extent of RRD, and severity of proliferative vitreoretinopathy between the juvenile and senile RRD groups. However, no statistical differences were evident in the final retinal reattachment rate (88.6% vs 94.9%; P = .413) or the final visual outcome (P = .902) between juvenile RRD and senile RRD. CONCLUSION: Clinical characteristics between juvenile and senile RRD are different. Although delayed diagnosis is common, the final surgical outcome in juvenile RRD is as promising as in senile RRD.

Adolescent↗

PubMedDate not supplied

The add-on effects of Gynostemma pentaphyllum on nonalcoholic fatty liver disease.

CONTEXT: Other than weight reduction by dieting or physical activity, there are no well-documented medical treatments for fatty liver disease. OBJECTIVE: To evaluate the efficacy of the add-on Gynostemma pentaphyllum (GP) in research subjects with nonalcoholic fatty liver disease. DESIGN: A randomized, single-blind, controlled clinical trial. SETTING: Hospital-based clinic. PATIENTS: Fifty-six research subjects who were diagnosed with nonalcoholic fatty liver by abdominal ultrasound scanning. INTERVENTIONS: The treatment group and the control group followed a controlled diet for 2 months. After 2 months, the treatment group continued to diet and received 80 mL GP extraction for 4 months; the control group continued to diet and received a placebo capsule for 4 months. MAIN OUTCOME MEASURES: Body mass index (BMI), biochemistry data, and fatty liver score were measured at baseline, at 2 months, and at 6 months. RESULTS: After 2 months of dieting, BMI and most biochemistry data decreased in both study groups. There were no significant differences in BMI or biochemistry data at month 2 between the 2 study groups. At month 6, BMI, triglyceride, aspartate aminotransferase (AST), alanine aminotransferase, alkaline phosphatase, insulin (ALP), insulin resistance index (HOMA-IR), and fatty liver score were reduced in both groups. The treatment group saw significant reductions in BMI, AST, ALP, insulin, and HOMA-IR, however. Changes in uric acid levels in the 2 groups from month 2 to month 6 were statistically significant (P = .028) CONCLUSION: GP is an effective adjunct treatment to diet therapy for patients with nonalcoholic fatty liver disease.

Adult↗