[Show abstract][Hide abstract] ABSTRACT: To examine the feasibility of image-guided navigation using transrectal ultrasound (TRUS) to visualize the neurovascular bundle (NVB) during robot-assisted laparoscopic radical prostatectomy (RALP). The preservation of the NVB during radical prostatectomy improves the postoperative recovery of sexual potency. The accompanying blood vessels in the NVB can serve as a macroscopic landmark to localize the microscopic cavernous nerves in the NVB.
A novel, robotic transrectal ultrasound probe manipulator (TRUS Robot) and three-dimensional (3-D) reconstruction software were developed and used concurrently with the daVinci surgical robot (Intuitive Surgical, Inc., Sunnyvale, CA) in a tandem-robot assisted laparoscopic radical prostatectomy (T-RALP).
After appropriate approval and informed consent were obtained, 3 subjects underwent T-RALP without associated complications. The TRUS Robot allowed a steady handling and remote manipulation of the TRUS probe during T-RALP. It also tracked the TRUS probe position accurately and allowed 3-D image reconstruction of the prostate and surrounding structures. Image navigation was performed by observing the tips of the daVinci surgical instruments in the live TRUS image. Blood vessels in the NVB were visualized using Doppler ultrasound.
Intraoperative 3-D image-guided navigation in T-RALP is feasible. The use of TRUS during radical prostatectomy can potentially improve the visualization and preservation of the NVB. Further studies are needed to assess the clinical benefit of T-RALP.
[Show abstract][Hide abstract] ABSTRACT: Precise targeting is essential for adequate treatment of lesions during image-guided therapy. The aim of this study was to compare the performance of two emerging image-guided targeting technologies in a phantom model.
A computer-assisted navigation system and AcuBot were tested using three operators: an interventional radiologist and two endourologists. Fiducials were placed in an anatomic gelatin phantom and targeted by both systems. The images were reconstructed and analyzed using a specialized software package (Amira; Visage Imaging, Carlsbad, CA). Accuracy was assessed by measuring proximity of the tip of the needle to the fiducial on computed-tomography-guided imaging. Accuracy and time to target were quantified and compared.
The mean distance from the desired target for AcuBot was 1.2 mm (range: 0.39-2.82). The mean distance from the desired target for the navigation system was 5.8 mm (range: 1.8-11.9). The AcuBot was significantly more accurate than the navigation system (p < 0.0001). The mean time from target acquisition to needle placement was 37 seconds (range: 15-75) for the AcuBot and 108 seconds (range: 45-315) for the navigation system (p = 0.001).
Emerging technologies hold promise for increased accuracy during percutaneous targeted procedures. Both the AcuBot and the computer-assisted navigation system were accurate and efficient in a phantom targeting model. AcuBot was significantly more accurate, faster, and less user dependent than the navigation system. Further studies in animal and clinical studies are warranted to further advance this promising technology.
Journal of endourology / Endourological Society 08/2010; 24(8):1269-72. · 1.75 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The purpose of this study was to examine the triage role of scrotal Doppler ultrasonography (DUS) as the primary preoperative diagnostic tool in patients presenting to the emergency department (ED) with acute scrotum.
Patients who presented to the ED with acute scrotum and underwent scrotal DUS in the ultrasound unit over a 3-year period (2004-2007) were included in the study. Patient characteristics, DUS findings, and clinical management were retrospectively collected and reviewed. Doppler ultrasonographic diagnoses were compared with histopathologic findings for patients who underwent exploration and with final diagnoses at the time of discharge for patients undergoing medical treatment.
A total of 620 consecutive patients with 669 DUS examinations were included. The most common scrotal DUS diagnoses were epididymitis, hydrocele, varicocele, and orchitis. Scrotal trauma was present in 77 cases. Hospitalization followed the initial ED evaluation for 155 patients; 68 underwent surgery. Testicular torsion was ultrasonographically suspected in 20 patients and confirmed in 18. Scrotal malignancy was incidentally diagnosed in 13 patients and testicular hematoma in 8. Doppler ultrasonography for the diagnosis of testicular torsion had 94% sensitivity, 96% specificity, 95.5% accuracy, an 89.4% positive predictive value (PPV), and a 98% negative predictive value (NPV). Doppler ultrasonography for the diagnosis of testicular malignancy had 92% sensitivity, 95% specificity, 94% accuracy, a 78.5% PPV, and a 98% NPV.
Scrotal DUS is a highly sensitive preoperative diagnostic tool, thereby validating its routine use in the initial triage of patients with acute scrotum presenting to the ED.
Journal of ultrasound in medicine: official journal of the American Institute of Ultrasound in Medicine 01/2010; 29(1):11-21. · 1.40 Impact Factor