Browsing by Author "Chiu Y.-S."

Computer aided surgery (CAS) had been an important research topic in recent years. 3D navigation is the crucial technique in the CAS applications. In this paper, a sound-guided 3D navigation system used for the retained auricular prosthesis surgery wad developed. This system consists of a 3D digitizer arm, a 3D space coordinate transformation module and a sound-guided navigation module. A 3D digitizer is a 5 degree-of-freedom passive robotic arm, and it is used to measure the coordinates of the registration and implant landmarks of the patient. The measured coordinates of landmarks are further compared with the patient's 3D reconstruction computer model that is constructed in terms of the computed tomography (CT) images to calculate the coordinate transformation matrix. The transformed implant coordinates are desired for the real-time navigations. In addition, the proposed sound-guided navigation module provides the real-time surgical guidance based on different audio tones and intermittence frequencies to improve the surgical accuracy. Finally, a clinical study of the retained auricular prosthesis surgery is introduced in this paper. Based on the results of the clinical validation, the proposed system effectively assistants the surgeon to increase the surgical quality and reduce the surgical time as well.

The fast growing computer technology had been successfully applied to the industry and medical applications. The operation efficiency, system accuracy, and quality consistency can be significantly improved by introducing the computer techniques. In recent years, several works combine the techniques of the computer software, machine vision and image processing to assist the surgeons to improve the surgical quality. Especially, the surgery navigation system is more emphasized than ever. In this paper, we propose a computer assisted retained auricular prosthesis surgery system. In this work, a 3D digitizer is used to measure the coordinate and posture of the patient. The patient's coordinate is further transformed to the coordinate of the computer model. In addition, a sound-based navigation system is developed to guide the surgeon to reach the registration position that was identified at the pre-surgery stage. Finally, a clinical case of the retained auricular prosthesis surgery of the microtia children was proposed and successfully validated.

We describe a case of empyema thoracis caused by Rhizopus oryzae diagnosed in an allogenic bone marrow transplant patient with acute lymphocytic leukemia. The isolate of R. oryzae was recovered from three pleural effusion specimens, which were black in color. It was identified on the basis of characteristic colonial appearance and microscopic findings, as well as the partial sequencing of rRNA genes. The patient died of uncontrolled R. oryzae empyema thoracis and concomitant nosocomial infection. ? 2006 ISHAM.

Background/Purpose: Limited information exists about the epidemiologic characteristics of HIV-negative patients with Mycobacterium tuberculosis bacteremia (MTB). Methods: We retrospectively surveyed tuberculosis (TB) cases reported at National Taiwan University Hospital between 1997 and 2003. Demographic data, underlying diseases or conditions, clinical, microbiologic and radiologic findings and therapy were collected. Long-term outcome was evaluated at 1 year after initiation of anti-TB agents. Results: During the study period the incidence of MTB bacteremia in HIV-negative patients and HIV-positive patients were 0.024 and 6.2 per 1000 discharges, respectively (p < 0.01). All 11 HIV-negative patients were males and eight (73%) were more than 50 years old. The most common underlying diseases/conditions were immunosuppressive therapy (64%) and heart disease (55%). Fever (80%), lymphopenia (75%) and pulmonary symptoms (58%) were the most common presentations. Ten patients were septic, two had septic shock and two had acute respiratory distress syndrome on admission. The median interval between admission and initiation of therapy for those who were cured was 6 days. Six (55%) died of TB and/or their underlying diseases. Of the six patients who died, the median survival after collection of positive blood culture was 19 days for three treated patients and 7 days for three untreated patients (p=0.01). Conclusion: This case series demonstrates the wide spectrum of the initial presentation of HIV-negative patients with MTB bacteremia. The case fatality rate was high and was likely due to immunocompromised status and no anti-TB treatment prior to death. A high index of suspicion for TB and blood culture for MTB provides an additional simple and noninvasive diagnostic method to detect disseminated TB in endemic areas. ? 2007 Elsevier & Formosan Medical Association.

Background and Purpose: The minimal inhibitory concentrations (MICs) of amphotericin B (AmB) determined by the National Committee for Clinical Laboratory Standards (NCCLS; NCCLS document M27-A) broth dilution method are in a relatively narrow ranges and this may lead to underestimation of the AmB-resistant rate in clinical isolates. We evaluated in vitro susceptibility of clinical isolates of Candida spp. to AmB using Etest and determined the distribution of AmB MICs in different species. Methods: We used the Etest (AB Biodisk, Solna, Sweden) to evaluate the MICs of Candida isolates randomly collected during 2001-2003 in a teaching hospital. Results: Of the 572 isolates evaluated, Candida albicans (50.7%) was the most common species, followed by Candida tropicalis (23.9%), Candida parapsilosis (13.1%), Candida glabrata (9.4%), Candida krusei (1.9%), and Candida guilliermondii (0.9%). The majority of isolates were from blood (85%). The minimal concentrations of AmB required to inhibit 50%/90% of the isolates (MIC50.MIC90) were 0.19/0.38 μg/mL for C. krusei, 0.125/0.38 μg/mL for C. glabrata, 0.094/0.25 μg/mL for C. tropicalis, 0.032/0.19 μg/mL for C. albicans, 0.016/0.125 μg/mL for C. parapsilosis, and 0.023/0.032 μg/mL for C. guilliermondii. Only 1 blood isolate of C. glabrata was resistant to AmB (MIC ?1 μg/mL) [0.17%]. 18.2% of isolates were less susceptible to AmB (MIC ?0.19 μg/mL) with the highest rates for C. krusei (63.6%), followed by C. glabrata (37.0%), C. tropicalis (29.9%), C. albicans (11.0%), C. parapsilosis (5.3%), and C. guilliermondii (0%). More isolates collected from patients with hematologic malignancy were less susceptible to AmB than those collected from those with other diseases (30.5% vs 15.4%, p<0.05). Conclusion: This study demonstrated that AmB resistance remains rare at this hospital in Candida clinical isolates despite increasing use of this agent during the past 4 decades. ? 2006 Journal of Microbiology, Immunology and Infection.

We report a protracted course of disseminated candidiasis due to Candida tropicalis in a 17-year-old man with acute lymphocytic leukemia. Despite adequate antifungal therapy (amphotericin B), C. tropicalis was recovered from biopsy specimens 25 days (skin) and 109 days (kidney) after the first positive blood cultures. While blood cultures became negative for C. tropicalis 11 days after the initiation of treatment, mannanemia persisted and became negative only after 130 days of antifungal therapy. Thus, antigen assays provided indicators of antifungal response. Differential diagnosis was difficult for this patient with the observation of persistent lesions in image studies. With positive results of antigen assays, an invasive procedure might be avoided and preemptive antifungal treatment could be initiated in a timely manner. Anti-mannan antibody remained undetectable up to 164 days after first positive blood culture despite the patient's recovery from neutropenia and recruitment of neutrophils in the tissue (skin).