Biomedical subjects

Z Lidar

Publications and source records attributed to Z Lidar.

3 recordsLinked to original sources

PubMed2001

Monitoring response to convection-enhanced taxol delivery in brain tumor patients using diffusion-weighted magnetic resonance imaging.

Convection-enhanced drug delivery (CEDD) is a novel approach to enhance the delivery of drugs directly into brain tumors. We have used diffusion-weighted MRI (DWMRI) to monitor the effects of intratumoral CEDD in three brain tumor patients treated with Taxol. Clear changes in the images and the water diffusion parameters were observed shortly after the initiation of treatment. Initially, a bright area corresponding to decreased diffusion appeared, followed by the appearance of a dark area of increased diffusion within the bright area. The time to appearance of the dark area varied among the patients, suggesting different response rates. In this work, we have demonstrated the feasibility of using DWMRI as a noninvasive tool to achieve unique early tissue characterization not attainable by other conventional imaging methods.

Antineoplastic Agents, Phytogenic↗

PubMed2001

Linear accelerator radiosurgery for vestibular schwannoma.

OBJECT: The use of radiosurgery in the treatment of acoustic neuromas has increased substantially during the last decade. Most published experience relates to the use of the gamma knife. In this report, the authors review the methods and results of linear accelerator (LINAC) radiosurgery in 44 patients with acoustic neuromas who were treated between 1993 and 1997. METHODS: Computerized tomography scanning was selected as the stereotactic imaging modality for target definition. A single, conformally shaped isocenter was used in the treatment of 40 patients; two or three isocenters were used in four patients who harbored very irregular tumors. The radiation dose directed to the tumor border was the only parameter that changed during the study period: in the first 24 patients who were treated the dose was 15 to 20 Gy, whereas in the last 20 patients the dose was reduced to 11 to 14 Gy. After a mean follow-up period of 32 months (range 12-60 months), 98% of the tumors were controlled. The actuarial hearing preservation rate was 71%. New transient facial neuropathy developed in 24% of the patients and persisted to a mild degree in 8%. Radiation dose correlated significantly with the incidence of cranial neuropathy, particularly in large tumors (> or = 4 cm3). CONCLUSIONS: Single-isocenter LINAC radiosurgery proved to be an effective treatment for acoustic neuromas in this series, with results that were comparable with those reported for gamma knife radiosurgery and multiple isocenters.

Adult↗

PubMed2000

Laparoscopic interval appendectomy for periappendicular abscess.

BACKGROUND: Laparoscopic appendectomy was first described in the early 1980s and is currently widely used for the treatment of acute appendicitis. The application of laparoscopic techniques to interval appendectomy and the value of this procedure as compared to open elective interval appendectomy remains uncertain. Therefore, we set out to assess the usefulness of interval laparoscopic appendectomy following periappendicular abscess. METHODS: This study analyzes the data for 10 patients who underwent interval laparoscopic appendectomy 8-10 weeks following documented periappendicular abscess in the period between January 1996 and June 1998. RESULTS: Laparoscopic appendectomy was completed successfully in all 10 patients. Nine patients were discharged 1 day after the operation; one patient was discharged on the evening of the operative day. There were no complications and no wound infections. CONCLUSION: We conclude that the laparoscopic approach is the preferable treatment for interval appendectomy. It is associated with minimal or no morbidity and a very short hospital stay.

Abdominal Abscess↗