Office Urologic Ultrasound

Content and face validation of a curriculum for ultrasonic propulsion of calculi in a human renal model

PURPOSE

Ultrasonic propulsion to reposition urinary tract calculi requires knowledge about ultrasound image capture, device manipulation, and interpretation. The purpose of this study was to validate a cognitive and technical skills curriculum to teach urologists ultrasonic propulsion to reposition kidney stones in tissue phantoms.

MATERIALS AND METHODS

Ten board-certified urologists recruited from a single institution underwent a didactic session on renal ultrasound imaging. Subjects completed technical skills modules in tissue phantoms, including kidney imaging, pushing a stone through a translucent maze, and repositioning a lower pole calyceal stone. Objective cognitive and technical performance metrics were recorded. Subjects completed a questionnaire to ascertain face and content validity on a five-point Likert scale.

RESULTS

Eight urologists (80%) had never attended a previous ultrasound course, and nine (90%) performed renal ultrasounds less frequently than every 6 months. Mean cognitive skills scores improved from 55% to 91% (p<0.0001) on pre- and post-didactic tests. In the kidney phantom, 10 subjects (100%) repositioned the lower pole calyceal stone to at least the lower pole infundibulum, while 9 (90%) successfully repositioned the stone to the renal pelvis. A mean±SD (15.7±13.3) pushes were required to complete the task over an average of 4.6±2.2 minutes. Urologists rated the curriculum's effectiveness and realism as a training tool at a mean score of 4.6/5.0 and 4.1/5.0, respectively.

CONCLUSIONS

The curriculum for ultrasonic propulsion is effective and useful for training urologists with limited ultrasound proficiency in stone repositioning technique. Further studies in animate and human models will be required to assess predictive validity.

Is the Pocket Ultrasound the “Phonendoscope” of the Urologist?

The objective was to evaluate the utility of the “pocket ultrasound” in making clinical decisions in urologic emergencies. From May to September 2011, 105 patients were assessed for urologic emergencies: acute flank pain, macroscopic hematuria, urinary retention, and lower urinary tract symptoms. All patients underwent an ultrasonographic examination whereby the pocket ultrasound was used to evaluate the kidneys and bladder, followed by another appropriate diagnostic test to verify the suggested diagnosis. Urinary retention was diagnosed in 10 patients. Of 48 subjects with hematuria, 34 had an immediate diagnosis: there were 18 cases of a bladder tumor, 13 cases of urolithiasis, and 2 cases of renal cell carcinoma; one ureteral stent was detected. Of 30 patients referred with lower urinary tract symptoms, 14 showed a high post micturition residual and 2 were seen to have bladder diverticula. Of 17 patients with acute flank pain, 1 had a kidney abscess, 5 had hydronephrosis, and 11 had urolithiasis. Ultrasonography provided a conclusive diagnosis in 67.6% of cases. Point-of-care pocket ultrasound allows a rapid diagnosis for treatment or triage of patients for appropriate referral to other diagnostic methods.

Effectiveness of ultrasonography in the postoperative follow-up of pediatric patients undergoing ureteroscopic stone manipulation

OBJECTIVES

To evaluate the effectiveness of ultrasonography and to determine whether ionizing radiation is necessary in the postoperative follow-up of children undergoing ureteroscopy.

METHODS

We reviewed the charts of 49 children who underwent 51 ureteroscopic procedures for ureteral calculi. Renal ultrasound and intravenous urography were performed in all patients at 3 months after surgery for postoperative evaluation.

RESULTS

In three cases, stones migrated to the kidney. Retrograde intrarenal surgery was performed in two patients and one patient required shockwave lithotripsy to become stone-free. Fourty-six children were completely stone-free and 3 had residual fragments on plain film in the postoperative 3 month. The sensitivity, specificity, negative and positive predictive values of ultrasonography for detecting hydronephrosis were 85.7, 100, 97.7 and 100%, respectively. Two patients under observation and three patients under medical expulsive therapy had resolution of hydronephrosis on follow-up. One patient required ureteroscopy for residual obstructing fragments.

CONCLUSIONS

Ultrasonography has limited accuracy for detecting residual ureteral stones, but it is a highly specific and reasonably sensitive test for detecting hydronephrosis. A combination of ultrasonography and plain film is a safe and effective imaging procedure in postoperative follow-up of children undergoing ureteroscopy.

What's New in Urologic Ultrasound?

Ultrasonography allows providers to noninvasively image an area of interest in real time without the risks of ionizing radiation or nephrotoxic contrast agents. This article present basic concepts of ultrasound along with new advances in ultrasound technology and their applications in small parts evaluation.