Figure 4.

“DO”—a struggle for supremacy between opening and closure reflexes. Actual urodynamic graph B = bladder chart; U = urethral chart; CP = closure pressure chart. Because the system is binary, the closure reflex “C” (red unbroken lines) and opening (micturition) reflex “O” (black broken lines) struggle for supremacy. This is a urodynamic graph of a patient with OAB symptoms, with a full bladder, undergoing a handwashing test. The sequence of events is identical to that seen in normal micturition [1] a feeling of urgency, [2] a fall in urethral pressure “X” (graph “U”), [3] a rise in bladder pressure “Y” (graph “B”) [4] urine loss, black arrow, (graph ‘CP’). U = urethral pressure graph; B = bladder pressure graph; CP = closure pressure graph (U minus B). C = closure reflex (red unbroken lines). O = opening (micturition) reflex, (black broken lines) with its components being: Ou = urethral relaxation. Od = detrusor contraction. Om = opening out of the outflow tract by backward/downward striated muscle forces, X‐ray Figure 3. Cm = closure reflex regains control by contraction of pelvic closure muscles, X‐ray Figure 2. The thin blue and red arrows in “B” reflect the struggle between the closure reflex (peak) and the opening reflex (trough)