Biomedical subjects

A Herline

Publications and source records attributed to A Herline.

4 recordsLinked to original sources

PubMed2005

Ultrasound-to-computer-tomography registration for image-guided laparoscopic liver surgery.

BACKGROUND: The application of image-guided surgery (IGS) to laparoscopic liver resection and ablation is currently limited, but it would assist in intraoperative decision making regarding oncologic margins, ablation probe placement, and ablation tracking. METHODS: Eight spherical surface targets on a liver phantom were imaged with an optically tracked laparoscopic ultrasound (US) probe. Ten US images of each target were registered to computer tomography (CT) images of the phantoms and then mapped to the CT scans. Accuracy of the registration was assessed by comparing the distance between the predicted target location and the position obtained directly from CT. RESULTS: The average localization error was 5.3 mm. The errors resulted primarily from inaccurate US probe tracking but were otherwise insensitive to the variability that arises from manually identifying targets in US and CT images. CONCLUSIONS: The results obtained for US-to-CT registration in a phantom model suggest that further investigations into its clinical use are warranted and that other IGS technologies could be applied to laparoscopic liver surgery as well.

Hepatectomy↗

PubMed2001

Bile duct injury following laparoscopic cholecystectomy: a cause for continued concern.

Previous reports suggest that bile duct injuries sustained during laparoscopic cholecystectomy (lap chole) are frequently severe and related to cautery and high clip ligation. We performed a review of patients who sustained bile duct injury from lap chole since 1990 and assessed time to injury recognition, time to referral, Bismuth classification, initial and subsequent repairs, rate of recurrence, and length of follow-up. Seventy-four patients [median age 44 years, 58 of 74 female (78%)] were referred with a bile duct injury after lap chole. The level of injury was evenly divided between the bile duct bifurcation and the common hepatic duct: Bismuth III, IV, and V (40 of 74, 54%) versus Bismuth I and II (34 of 74, 46%). Concomitant hepatic arterial injury was identified in nine (12%) patients. Patients referred early after bile duct injury and requiring operative intervention underwent hepaticojejunostomy at a median of 2 days after referral. After surgical reconstruction at our center there has been an overall success rate of 89 per cent with no need for reintervention. Six (10%) of these patients have required one additional balloon dilatation at a mean follow-up of >24 months. One (2%) patient underwent biliary-enteric revision in follow-up. In patients with bile duct injury, stricture repair without delay was successful in the majority of patients treated in this series. Only one of 64 patients reconstructed at our center has required reoperation; six others have required a single balloon dilatation with subsequent good or excellent results. The majority of patients treated with operative repair at an experienced center can expect good long-term results with rare need for reintervention.

Adolescent↗

PubMed2000

Technical advances toward interactive image-guided laparoscopic surgery.

BACKGROUND: Laparoscopic surgery uses real-time video to display the operative field. Interactive image-guided surgery (IIGS) is the real-time display of surgical instrument location on corresponding computed tomography (CT) scans or magnetic resonance images (MRI). We hypothesize that laparoscopic IIGS technologies can be combined to offer guidance for general surgery and, in particular, hepatic procedures. Tumor information determined from CT imaging can be overlayed onto laparoscopic video imaging to allow more precise resection or ablation. METHODS: We mapped three-dimensional (3D) physical space to 2D laparoscopic video space using a common mathematical formula. Inherent distortions present in the video images were quantified and then corrected to determine their effect on this 3D to 2D mapping. RESULTS: Errors in mapping 3D physical space to 2D video image space ranged from 0.65 to 2.75 mm. CONCLUSIONS: Laparoscopic IIGS allows accurate (<3.0 mm) confirmation of 3D physical space points on video images. This in combination with accurately tracked instruments and an appropriate display may facilitate enhanced image guidance during laparoscopy.

Equipment Design↗

PubMed1994

Thoracic empyema in a patient with acute appendicitis: a rare association.

Thoracic empyema and appendicitis rarely are concomitant. This is the first report of ultrasonography and computed tomography being used preoperatively to establish the diagnosis of ruptured appendicitis in a child with thoracic empyema. The perforated appendicitis was identified after gastrointestinal flora were cultured from the thoracostomy drainage of the empyema.

Acute Disease↗