Publications by authors named "Caroline Ames"
Background: Controversy exists about the impact of ischemia on renal function. We evaluated the creatinine clearance of patients having undergone laparoscopic renal extirpative and ablative surgery.
Study Design: The records of patients undergoing laparoscopic procedures for renal masses from February 2000 to March 2004 were examined.
Purpose: We analyzed the smoke plume produced by various energy-based laparoscopic instruments and determined its effect on laparoscopic visibility.
Materials And Methods: The Bipolar Macroforceps, Harmonic Scalpel, Floating Ball, and Monopolar Shears were applied in vitro to porcine psoas muscle. An Aerodynamic Particle Sizer and Electrostatic Classifier provided a size distribution of the plume for particles >500 nm and <500 nm, and a geometric mean particle size was calculated.
Objectives: To report our experience with laparoscopic renal cryoablation for patients who have completed a minimum of 3 years of follow-up.
Methods: From July 2000 to March 2005, 81 patients underwent laparoscopic renal cryoablation for renal masses. Of these 81 patients, 31 (38%) underwent laparoscopic renal cryoablation for 36 tumors and have completed a minimal follow-up of 3 years (mean 45.
Objective: To evaluate the association of variables of body habitus with direct measurements of ureteric length, as the correct choice of ureteric stent length might help to prevent complications and improve stent tolerance, and to date there are limited data correlating height or other body variables with ureteric length.
Patients And Methods: We prospectively measured pelvi-ureteric junction to vesico-ureteric junction length in 100 patients by placing a ruled 5 F ureteric catheter. Ureteric length was then correlated with patient height, weight, body mass index, and distance from the shoulder (acromium process) to the wrist (head of the ulna; S-W), the elbow (olecranon process) to the wrist (head of the ulna), xyphoid process to umbilicus, xyphoid process to pubis (X-P), umbilicus to pubis, and anterior iliac spine to anterior iliac spine.
Background And Purpose: Intraluminal application of pharmacologic agents for acute ureteral dilation may facilitate difficult ureteroscopy. We characterized the in-vivo effects of intraluminal application of verapamil and theophylline on ureteral peristalsis and diameter in a porcine model.
Materials And Methods: Twenty-four female domestic pigs (35-40 kg) were incorporated into the study.
Purpose: We characterized the size and shape of the ablated area, and the surrounding indeterminate zone associated with renal cryolesions produced by single and multiple cryoablation probe configurations in a porcine model.
Materials And Methods: Laparoscopic cryoablation, consisting of 2, 10-minute double freeze cycles followed by a 3-minute active thaw, was performed in 18 pigs. Three groups of 6 pigs each were studied, including a single IceRod, 3 rods arranged in a triangular configuration 2 cm apart from each other and 4 rods arranged in a quadratic configuration 2 cm from each other.
Objectives: To report our single institutional experience of laparoscopic partial nephrectomy (LPN) for enhancing renal masses and evaluate outcomes and histopathologic findings with respect to the location of the renal mass.
Methods: A retrospective review of LPN for 123 renal masses completed by 7 urologists was performed. Of these lesions, 49 (40%) were exophytic, 19 (15.
Purpose: We performed a randomized, prospective, multi-institutional study evaluating the durability of commercially available flexible ureteroscopes.
Materials And Methods: A total of 192 patients were randomized to the use of 7 less than 9Fr flexible ureteroscopes, including the Storz 11274AA and Flex-X, the ACMI DUR-8 and DUR-8 Elite, Wolf models 7330.170 and 7325.
Objectives: To evaluate a novel prototype self-anchoring suture (SAS) material that incorporates unidirectional "barbs" designed to grip and approximate tissue without the need for suture ligation for urinary tract reconstructive procedures.
Methods: The in vitro failure strength of various porcine tissue approximations with SAS was compared with the strength of similar approximations with standard ligated suture. For in vivo analysis, 3 pigs underwent laparoscopic pyeloplasty with SAS on one side and 2-0 Vicryl suture on the contralateral side.
Objectives: To evaluate the efficacy of transcutaneous electrical nerve stimulation (TENS) for its effectiveness in eliminating or minimizing discomfort during office-based flexible cystoscopy.
Methods: A total of 148 patients were prospectively randomized into one of three groups: flexible cystoscopy with no analgesics, a placebo TENS, or an activated TENS. The patient data collected included patient parameters, number of previous flexible cystoscopies, visual analog pain scores during and after the procedure, surgeon's difficulty rating of procedure, and International Prostate Symptom Score before and 24 hours after the procedure.
Objectives: To compare the mechanical and clinical performance of new and reprocessed harmonic scalpels (HS).
Methods: A total of 89 reprocessed and 90 new HS (laparoscopic coagulating shears with a curved blade and 5-mm-diameter shaft) were subjected to visual inspection, destructive testing, and nondestructive mechanical testing. Subsequently, new HS, randomly selected reprocessed HS, and selected reprocessed HS with known abnormalities were graded on clinical performance by 14 surgeons in a porcine model.
Background And Purpose: Optimal placement allows intuitive laparoscope positioning between two working trocars (0 degrees angle). However, this configuration may require the assistant to operate in an awkward position. We evaluated the effect of alteration of laparoscope position on surgeon performance and correlated this with surgical experience.
View Article and Find Full Text PDFBackground And Purpose: Introduction of an instrument into the working channel of ureteroscopes adversely affects flow and deflection. We evaluated the alterations in ureteroscope channel flow and deflection caused by available Nitinol(R) baskets.
Materials And Methods: We compared the effects of 11 Nitinol baskets on irrigation flow and deflection of three flexible ureteroscopes (Olympus P3, ACMI DUR8, and ACMI DUR8 Elite).
Background And Purpose: Various laparoscopic devices have been described for suture anchoring during solidorgan parenchymal closure. Application of these devices expedites the closure of parenchymal defects and minimizes ischemia time. We compared different technologies as suture anchors for parenchymal closure.
View Article and Find Full Text PDFObjectives: To evaluate the feasibility of selective segmental artery clamping during partial nephrectomy.
Methods: Precise extraparenchymal renal hilar dissection was performed on 73 fixed cadaveric kidneys. The surgical accessibility to clamping of each presegmental and segmental artery from the anterior and posterior approaches was determined on the basis of vessel length, position within the renal hilum, and degree of overlying collecting system or venous structures.
Purpose: To compare running and interrupted suturing techniques for porcine vesicourethral anastomosis with regard to procedure time, histopathologic effects, and leakage.
Materials And Methods: Twelve domestic pigs were randomized to a running (N = 6) or an interrupted (N = 6) vesicourethral anastomosis with polyglycolic acid sutures. In each case, the bladder was drained for 7 days.
Objectives: To compare two second-generation hand-assist devices (HADs) for surgeon pain and manual blood flow over time in an in vitro model.
Methods: Nineteen participants placed their nondominant hand through both the LapDisc and GelPort into a pneumoperitoneum chamber with an insufflation pressure of 15 mm Hg for a 2-hour test period. Pain, on a 10-point visual analog scale, and manual blood flow to the index finger using a laser Doppler skin probe were measured at 10 points during the 2 hours.
Objectives: To evaluate the time required for each component of laparoscopic radical prostatectomy (LRP) performed by a single surgeon to identify the factors that expedite the learning curve. LRP is a technically demanding procedure with a lengthy learning curve.
Methods: The LRP procedure was divided into 12 steps, and the time for each step was prospectively recorded during the first 50 consecutive patients undergoing LRP by a single surgeon.
Purpose: Gas embolization is a well documented complication of laparoscopic surgery. We evaluated the association of gas embolization with increased intra-abdominal pressure (IAP) in the porcine model during laparoscopic partial nephrectomy with real-time transesophageal echocardiography.
Materials And Methods: Eight domestic pigs weighing 143 to 162 pounds underwent unilateral transperitoneal laparoscopic heminephrectomy with renal artery clamping with varied IAPs.
Objectives: To compare two different distal sensor flexible endoscopes with standard fiberoptic cystoscopes for optical resolution. Distal video sensor flexible endoscopy may represent the cusp of a new endoscopic revolution.
Methods: Twenty-three participants evaluated the optical resolution capabilities of six flexible cystoscopes.
Objectives: To evaluate the utility of the porcine and canine models for collecting system closure after partial nephrectomy involving violation of the renal collecting system. Advanced surgical technologies and novel techniques for performing laparoscopic partial nephrectomy are frequently evaluated in an animal model.
Methods: After evaluation of the upper urinary tract with retrograde pyelography, laparoscopic partial nephrectomy, including violation of the renal collecting system, was performed in 8 domestic pigs (group 1) and 2 dogs (group 2) with documented normal upper urinary tract physiology.
Objectives: To report the development of a novel, simple-to-use method for laparoscopic deployment of fine-quality saline ice slush by way of a 10-mm end-effector for laparoscopic parenchymal hypothermia.
Methods: A mechanism for making fine ice slush was created, and a 10-mm laparoscopic end-effector was designed and constructed for deployment of the ice slush. The novel ice slush deployment system was tested in a porcine model and compared with that of standard open ice slush cooling.
Objectives: To develop and test a porcine model to help teach the techniques needed to perform laparoscopic partial nephrectomy (LPN), which is a technically challenging procedure with necessary reconstructive skills that are difficult to transfer.
Methods: A tumor model was created by unilateral subcapsular percutaneous injection of liquid plastic (Smooth-Cast 320) in five pig kidneys. Five Washington University urologists performed LPN and assessed the efficacy of the tumor model.
We investigated the relationship between plasma and yolk oestrogens in laying female zebra finches (Taeniopygia guttata) by manipulating plasma oestradiol (E2) levels, via injection of oestradiol-17beta, in a sequence-specific manner to maintain chronically high plasma levels for later-developing eggs (contrasting with the endogenous pattern of decreasing plasma E2 concentrations during laying). We report systematic variation in yolk oestrogen concentrations, in relation to laying sequence, similar to that widely reported for androgenic steroids. In sham-manipulated females, yolk E2 concentrations decreased with laying sequence.
View Article and Find Full Text PDFPurpose: While the use of ureteral access sheaths facilitates flexible ureteroscopy, buckling or kinking of the device may preclude its successful application. We evaluate the ability of 2 hydrophilic coated ureteral access sheaths to obtain and maintain access to the upper collecting system.
Materials And Methods: A total of 54 flexible ureteroscopy procedures were randomized to use of the 12/15Fr Applied Access Forte XE (Applied Medical, Rancho Santa Margarita, California) or the 12/14Fr Cook Flexor (Cook Urological, Spencer, Indiana) access sheaths.