Biomedical subjects

Ma Xin

Publications and source records attributed to Ma Xin.

3 recordsLinked to original sources

PubMed2006

A virtual reality simulator for remote interventional radiology: concept and prototype design.

We present a virtual reality simulator to realize interventional radiology (IR) procedures remotely. The simulator contains two subsystems: one at the local site and the other at the remote site. At the local site, the interventional radiologist interacts with a three-dimensional (3-D) vascular model extracted from the patient's data and inserts IR devices through the Motion Tracking Box (MTB), which converts physical motion (translation and rotation) of IR devices into digital signal. This signal is transferred to the Actuator Box (AB) at the remote site that drives the IR devices in the patient. The status of the IR devices is subsequently fed back to the local site and displayed on the vascular model. To prove the concept, the prototype developed employs a physical angiography phantom (mimicking the patient) and its corresponding 3-D digital model. A magnetic tracking system provides information about positioning of the IR devices in the phantom. The initial results are encouraging. The AB controlled remotely drives IR devices with resolution of 0.00288 mm/step in translation and 0.079 deg/step in rotation.

Angiography↗

PubMed2004

Retroperitoneoscopic subcapsular nephrectomy for infective nonfunctioning kidney with dense perinephric adhesions.

OBJECTIVE: To evaluate the feasibility and clinical efficacy of retroperitoneoscopic subcapsular nephrectomy for infective nonfunctioning kidneys with dense perinephric adhesions. PATIENTS AND METHODS: Twelve patients underwent retroperitoneoscopic subcapsular nephrectomy; the operative duration, blood loss, intestinal functional recovery time, complications during surgery and efficacy were recorded. Dissociation and ligation of the renal pedicle was the most important step, at which the renal capsule was cut near the renal hilum using a harmonic scalpel, and the fatty tissue around the renal hilum dissected carefully. The renal pedicle was then ligated and divided using an endoscopic linear stapler-cutter after the renal pedicle tissues had been separated to an adequate thickness. RESULTS: All 12 operations were successful and none required conversion to open surgery. The mean (SD, range) operative duration was 82.9 (22.3, 45-120) min, the blood loss 51.4 (12.2, 30-75) mL and the intestinal functional recovery time 12-48 h. There were no complications during or after the surgery, and in the follow-up of 1-15 months the short-term results were satisfactory. CONCLUSION: Retroperitoneoscopic subcapsular nephrectomy can be used safely to remove an infected and heavily adhesive nonfunctioning kidney, with minimal trauma and blood loss, and with faster recovery than after an open subcapsular nephrectomy.

Adult↗

PubMed2003

Comparison of open surgery versus retroperitoneoscopic approach to chyluria.

PURPOSE: We compared the clinical effectiveness of renal pedicle lymphatic disconnection for chyluria performed by retroperitoneoscopy and by open surgery. MATERIALS AND METHODS: Three male and 4 female patients 33 to 68 years old (mean age 49) with chyluria underwent retroperitoneoscopic renal pedicle lymphatic disconnection. Chyluria was on the left side in 5 cases and on the right side in 2. Open renal pedicle lymphatic disconnection was performed in 4 men and 2 women 33 to 61 years old (mean age 45.8). Chyluria was on the left and right sides in 3 cases each. Mean operative time, intraoperative blood loss, postoperative intestinal function recovery time, intraoperative and postoperative complications, postoperative hospital delay and operative outcome were compared in these 2 groups. RESULTS: Compared with the open surgery group results in the retroperitoneoscopic group were superior in terms of operative time (42 to 90 minutes, mean +/- SD 65.0 +/- 18.8 versus 120 to 220, mean 156.7 +/- 38.8), intraoperative blood loss (20 to 50 ml., mean 29.3 +/- 10.2 versus 60 to 250, mean 171.7 +/- 76.5), postoperative intestinal function recovery time (24 to 48 hours, mean 36.0 +/- 6.9 versus 24 to 72, mean 54.0 +/- 21.1), intraoperative and postoperative complications, and postoperative hospital stay (3 to 6 days, mean 4.7 +/- 0.7 versus 7 to 9 days, mean 7.8 +/- 1.0). In the open surgery group primary anastomosis was performed in 1 case due to injury to a renal artery branch during the operation. Chyluria resolved the day after surgery in the 2 groups. No obvious complications developed postoperatively. The followup of 2 to 12 months (mean 6.7 +/- 4.0) showed no recurrence of chyluria. CONCLUSIONS: Retroperitoneoscopic renal pedicle lymphatic disconnection completely ligates the lymphatic vessels with minimal invasion, less blood loss, rapid recovery and a good short-term outcome.

Adult↗