Prospective, blinded comparison of laparoscopic ultrasonography vs. contrast-enhanced computerized tomography for liver assessment in patients undergoing colorectal carcinoma surgery.

PURPOSE: To prospectively and blindly compare intraoperative laparoscopic ultrasonography to preoperative contrast-enhanced computerized tomography in detecting liver lesions in colorectal cancer patients. Additionally, we compared conventional (open) intraoperative ultrasonography with bimanual liver palpation to contrast-enhanced computerized tomography in a subset of patients. METHODS: From December 1995 to March 1998, 77 consecutive patients underwent curative (n = 63) or palliative (n = 14) resections for colorectal cancer. All patients undergoing curative resections were randomized to either laparoscopic (n = 34) or conventional (n = 29) surgery after informed consent. All patients underwent contrast-enhanced computerized tomography, diagnostic laparoscopy, and laparoscopic ultrasonography before resection. In those patients who had conventional procedures, intraoperative ultrasonography with bimanual liver palpation was also done. All laparoscopic ultrasonography and intraoperative ultrasonography evaluations were performed by one of two radiologists who were blinded to the CT results. All hepatic segments were scanned using a standardized method. The yield of each modality was calculated using the number of lesions identified by each imaging modality divided by the total number of lesions identified. RESULTS: In 43 of the 77 patients, both the laparoscopic ultrasonography and CT scan were negative for any liver lesions. In 34 patients, a total of 130 lesions were detected by laparoscopic ultrasonography, CT, or both. When compared with laparoscopic ultrasonography, intraoperative ultrasonography with bimanual liver palpation identified one additional metastatic lesion and no additional benign lesions. laparoscopic ultrasonography identified two patients with mets who had negative preoperative contrast-enhanced computerized tomography. CONCLUSIONS: Laparoscopic ultrasonography of the liver at the time of primary resection of colorectal cancer yields more lesions than preoperative contrast-enhanced computerized tomography and should be considered for routine use during laparoscopic oncologic colorectal surgery.

Ultrasound-directed percutaneous endoscopic cyst-gastrostomy for the treatment of a pancreatic pseudocyst.

The incidence of pseudocysts in patients with chronic pancreatitis ranges from 20-40%. Unlike pseudocysts associated with acute pancreatitis, these do not usually resolve spontaneously. Traditionally, these cysts were drained surgically. More recently, however, they have been successfully managed with endoscopic drainage. This report reviews the history and results of nonsurgical pseudocyst management and describes a case of drainage obtained using an alternative method of ultrasound-directed percutaneous endoscopic cyst-gastrostomy.

Intraoperative laparoscopic liver ultrasonography for staging of colorectal cancer. Initial experience.

PURPOSE: This study was undertaken to evaluate the feasibility of intraoperative laparoscopic ultrasonography (ILUS) to completely scan all anatomic segments of the liver through a single port site during laparoscopic resection for colorectal cancer. METHODS: ILUS was performed in patients who were undergoing laparoscopic colorectal cancer surgery using the following approach: 1) presence of a radiologist in the operating room; 2) introduction of the probe through a single cannula site; 3) standardized sequence of four probe positions on liver surface; 4) identification of all major vascular/biliary hepatic structures as a guideline to scan all parenchymal segments of the liver. RESULTS: Twenty-two patients who were undergoing laparoscopic colorectal cancer surgery were prospectively enrolled. Computed tomography (CT) scan films were available for an immediate comparative analysis in the first 12 cases. Mean duration of the procedure was 10 (range, 5-15) minutes. All major vascular and biliary structures were identified in all patients. Sixteen focal abnormalities were identified by ILUS, and ten focal abnormalities were identified by CT scan in the same seven patients. In one patient, detection of a suspected metastasis not seen by preoperative CT scan led to conversion of the surgical procedure to a laparotomy. CONCLUSIONS: ILUS is a safe and expeditious technique that permits scanning of all anatomic liver parenchyma segments through a single cannula site. Because intraoperative palpation of the liver is not possible during laparoscopic colorectal cancer surgery, ILUS should probably be a standard component of the curative laparoscopic colorectal cancer operation.

Civilian field surgery in the rural trauma setting: a proposal for providing optimal care.

Rural trauma presents unique problems for surgical care. While military surgeons are prepared to provide care at or near the scene of battle, civilian literature is devoid of reports for care provided by surgeons at sites of injury occurrences. Although these injuries are infrequent, they are more likely to occur in rural trauma settings. This article describes two cases of extremity injury that required amputation at the scene and presents a proposal for swift mobilization of appropriately trained surgeons to the scene with adequate instrumentation and lighting, which can significantly reduce the morbidity and mortality of these victims.

Diagnostic efficacy of digitized images vs plain films: a study of the joints of the fingers.

Four hundred fifteen finger joints from 30 patients were evaluated for the presence of joint-space erosion, narrowing, and degenerative spurring on plain films, low-resolution digitized images (1024 x 840 bytes x 12 bit matrix), and high-resolution digitized images (2048 x 1680 bytes x 12 bit matrix). Three hundred four joints were abnormal. Low- and high-resolution digital images were displayed on a 1K x 1K monitor with the ability to change level, window, orientation, and brightness. Five radiologists interpreted images. The presence or absence of each abnormality was determined by consensus of two skeletal radiologists who did not otherwise participate in the study. Receiver-operating-characteristic analysis was used to obtain an area and a true-positive rate at a 0.10 false-positive rate for each interpreter. Randomized block analysis of variance with interpreters as blocks was used to compare areas and true-positive rates among imaging techniques for each type of abnormality; no statistically significant differences were found. In conclusion, the efficacy of display of digitized images on high- and low-resolution modes is not significantly different from that of plain films in the detection of erosions, joint-space narrowing, or degenerative spurring in small joints of the hands.

Renal artery stenosis: evaluation with color Doppler flow imaging.

Renal artery stenosis (RAS) is the most common correctable cause of hypertension. The current study was undertaken to evaluate the usefulness of color Doppler flow imaging as a screening examination in the detection of significant RAS. Fifty-five kidneys in 30 patients were examined with aortography and color Doppler flow imaging in a double-blind fashion. The peak systolic velocity (PSV) in the renal artery, the renal-aortic ratio (RAR) (ie, the ratio of the PSV in the renal artery to the PSV in the aorta), and the renal artery resistive index were determined and compared with the percentage of stenosis as determined with angiography. Ultrasound (US) criteria used to diagnose RAS were (a) an RAR of 3.5 or greater and/or (b) a renal artery PSV of greater than 100 cm/sec. Doppler tracings were obtained in 25 (69%) of 36 kidneys with a patent single renal artery. RAR and PSV each yielded a sensitivity of 0% in the diagnosis of RAS. Doppler tracings were obtained in three (50%) of six occluded renal arteries. Accessory arteries were present in 13 (24%) of 55 kidneys, but none were visualized with color Doppler flow imaging. The authors conclude that with current technical capability, color duplex US is not an adequate screening method for the detection of RAS.

Extended patency of expanded polytetrafluoroethylene grafts for vascular access using optimal configuration and revisions.

During a seven year period, 189 expanded polytetrafluoroethylene (PTFE) grafts for vascular access were implanted in 131 patients with end stage renal disease requiring long term hemodialysis. Over-all cumulative patency rate for all grafts was 76 per cent at 12 months, 50 per cent at 36 months and 40 per cent at 60 months. Forearm grafts of loop configuration yielded greater over-all patency rates and required fewer revisions than forearm grafts of straight configuration. Graft thrombosis was the universal indicator of graft malfunction. In the instance of a malfunction, immediate thrombectomy followed by angiography was considered essential to decisions regarding further therapy. Of 95 grafts that malfunctioned, 49 ultimately required revision, extending the survival to a rate equaling that of continuously functioning grafts. Extensive venous stenosis limiting outflow and multiple intragraft stenosis were the main causes of graft failure. For patients in whom all vessels of the upper extremity had been exhausted, thigh grafts of the loop configuration and axilloaxillary grafts proved to be satisfactory alternatives. Although PTFE grafts are not the final solution for vascular access in hemodialysis, in many instances, they will serve well, provided the surgeon gives proper consideration to their most efficacious use.