Performance analysis of the T-DOC® air-charged catheters: An alternate technology for urodynamics.

AIMS: Urodynamics (UDS) is widely used for the diagnosis of lower urinary tract dysfunction. Air-Charged catheters (ACC), one of the newer technologies for UDS pressure recording, has been adopted in growing numbers around the world for the past 15 years. Currently, there is a lack of published studies characterizing specific performance of the ACC. Since linearity, hysteresis, pressure drift, and frequency response are important components in characterizing accuracy for catheter-manometer systems; this study aimed to assess these four aspects in ACC. METHODS: A total of 180 T-DOC® ACC were used in three different laboratory settings to assess pressure linearity and hysteresis (15 dual-sensor vesical and urethral and 30 single-sensor abdominal), pressure drift over 2 h (115 single-sensor), and frequency response (20 single-sensor). Data are presented as mean ± standard deviation. RESULTS: ACC showed linearity of 0.99 ± 0.01, 0.99 ± 0.01, and 1.01 ± 0.01; and hysteresis of 0.57 ± 0.3%, 0.76 ± 0.48%, and 1 ± 0.89% for the abdominal, vesical, and urethral sensors, respectively. A pressure drift of 2.2 ± 1.4% at 1 h and 4.4 ± 2.5% at 2 h were observed when compared to baseline pressures. The catheters did not show any amplification factor during the sweep from 1 to 30 Hz, and recorded signals up to 5 Hz attenuating higher frequency signals. CONCLUSIONS: In this study the T-DOC® ACC showed a linear performance with minimal hysteresis associated with acceptable pressure drift, and adequate frequency response to capture clinically relevant pressures. The accurate results observed in this study suggest that these catheters are technically suitable to be used as a measuring instrument for UDS.

Comparing a novel hand held device (Peritron+) to standard urodynamics in measuring intravesical pressure.

AIMS: Peritron+ is a new handheld device, which can be attached to a urethral catheter to measure intravesical pressures (Pves). The goal of this study was to assess if Pves recorded by standard urodynamics (UDs) are comparable to those recorded by the Peritron+. METHODS: Patients with voiding dysfunction and an indication for UD underwent measurement of Pves with nonvideo UD and Peritron+. Pves were recorded at volumes of 50, 100, and 200 mL for the supine and sitting positions. A failure of the Peritron+ was considered to be a discrepancy of Pves values >3 cmH2 O between Peritron+ and UD recordings. Two-way ANOVA was used to assess for statistical significance. P-values < 0.05 were considered significant. RESULTS: Ten female patients, mean age 51 years old, were enrolled in the study. The difference in Pves measurements between Peritron+ and UD were ≤3 cmH2 O at all bladder volumes measured in a supine and sitting positions. There were no adverse events and there were no malfunctions of the Peritron+ device during the study. CONCLUSIONS: Peritron+ handheld device accurately assessed Pves at different intravesical volumes when compared to UD measurements. The Peritron+ is a simple and safe device, which can be used in the office by a clinician and at home by a patient to monitor Pves and help to select patients who may require standard UD re-evaluation. This will be a valuable tool in managing patients with neurogenic and nonneurogenic bladders who are at a risk of upper urinary tract deterioration.