How the Bladder Senses? A Five‐Grade Measure

<jats:p><jats:bold>Objectives:</jats:bold> During bladder filling, the bladder starts to sense it and the sensation steadily increases. However, little is known concerning volume‐sensory correlation in normal bladder and pressure‐sensory correlation during detrusor overactivity (DO). We aimed to real‐time assess bladder sensation in normal bladder and DO using a five‐grade measure.</jats:p><jats:p><jats:bold>Methods:</jats:bold> We enrolled 74 normal individuals and 87 patients with DO (51 terminal, 36 phasic). During slow bladder filling, we instructed individuals to indicate sensation in five grades: 1, first sensation; 2, obviously greater than 1 but less than 3; 3, first desire to void when he or she usually goes to toilet; 4, obviously greater than 3 but less than 5; and 5, strong desire to void. We also instructed individuals to report other sensations, such as pain.</jats:p><jats:p><jats:bold>Results:</jats:bold> The five‐grade measure is feasible in all participants, showing a volume and pressure‐ sensory correlation. Among the five grades, grade 0 to 1 was the longest, followed by grade 4 to 5, in all participants. Grade 0 to 1 in phasic DO and grade 4 to 5 in terminal and phasic DO were shorter than those in normal bladder (P < 0.05). Eighty‐six percent of patients with DO reported that the rapidly increased sensory grade is akin to urinary urgency in daily life.</jats:p><jats:p><jats:bold>Conclusion:</jats:bold> The five‐grade measure is feasible to assess a volume and pressure‐sensory correlation. Using this measure the sensory grade rapidly increased during DO compared with normal bladder, and 86% of the patients with DO reported that it is akin to urinary urgency in daily life.</jats:p>