InsKid-a new mobile application (app) that measures the infundibulopelvic angle before retrograde intrarenal surgery more reliably than does other approaches: pilot study

Evaluation of validity and reliability of novel rapid measurement for infundibulopelvic angle: a comparison with PACS system

BACKGROUND

For patients with lower pole renal calculi (LPC), preoperative evaluation of infundibulopelvic angles (IPA) is of great significance; however, conventional measuring method is often inconvenient in clinical setting. Here we introduce a rapid novel method using built-in inclinometer in smartphone which is often used in anatomical parameters evaluating to implement the measurement of IPA.

MATERIALS AND METHODS

The randomized, self-controlled study on evaluating inclinometer application measured IPA on urography films collected from enrolled LPC patients. Results of statistical analysis for its validity and reliability compared to conventional PACS system are reported. Predictive performance of postoperative stone-free rates by IPA measured with the novel method was also evaluated in this study.

RESULTS

Bland-Altman plot result shows that there is favorable agreement between IPA values of these two methods. The time required to utilize the PACS was considerably greater than time required to take similar measure using smartphones. The precision-recall curve (PRC) indicates that the new method has similar predictive performance for postoperative clearance rates as PACS.

CONCLUSIONS

In summary, measurement of IPA implemented by integrated inclinometer of smartphone is rapid, convenient, accurate and reliable in evaluating renal anatomy parameters of LPC patients.

Interior definition of the calyceal orientation suitable for percutaneous nephrolithotripsy via mobile software

To date, there is no paper on defining the puncture of a kidney from the interior view of the pelvicalyceal system (PCS) to alleviate its performance. The objective of this study is to define the usefulness of the Rubik's Cube method determining calyceal orientation from inside via mobile software for the percutaneous nephrolithotripsy (PCNL). Over September 2019-September 2020, 25 patients with indications for PCNL were enrolled in this single-arm study. All patients underwent computed tomography (CT)-urography. Primary endpoints were the duration of renal cavity puncture, number of attempts and success rate. Complication rate ordered according to Clavien-Dindo classification was analyzed as a secondary endpoint. The stone-free rate was 91%. The same experienced urologist performed all procedures through the single-access PCNL without puncture site reposition. The puncture was made through the upper, middle, and lower calyx in 9, 12 and 4 cases, respectively. The mean duration of cavity puncture was 2.8 ± 1.1 min. The mean number of attempts to reach desirable calyx was 1.4 ± 0.6. It should be noted that there were no cases with three and more punctures. The overall complication rate was 28% (7/25) when only one patient experienced ≥ 3 Grade. The proposed Rubik's Cube method facilitates preoperative planning of PCNL and makes that procedure easier for specialists and safer for the patients.