Aims of Study:
The diagnosis of voiding obstruction in women is very imprecise. Most of women with clinical bladder outlet obstruction present grade 0 and I in the Schäffer's Nomogram, not allowing an objective differentiation from normal voiding patients. The current difficult in establishing the correct diagnosis of obstruction in these women and the increasing incidence of this problem, stimulated us to develop this study, which intend to create a new approach to voiding obstruction in women, based on a modified Schäffer Nomogram.

Methods:
The initial two grades of Schaffer nomogram (grade 0 and grade I) were divided in subdivisions 0a, 0b, 0c, Ia and Ib, to obtain a more precise differentiation between female micturitions. Eleven women were analyzed according to this modified Schäffer Nomogram regarding symptoms of obstruction (weak urinary flow, strength to void, urgency, incomplete emptying bladder, urinary tract infections). The mean age of these patients was 56,5 years (31-74 y.o.). Nine patients had been submitted at least to one operation to urinary incontinence repair (retropubic colposuspension, anterior colporraphy, sling procedure and TVT), and the mean time from the operation was 27,5 months (4-60 m.).

Results:
Analysis of symptoms in the modified Schäffer Nomogram, revealed that patients with no symptoms of obstruction were absent after grade 0b. No patient was noted in the grade 0a; one symptomatic patient presented grade 0b; all patients in grade 0c and over were symptomatic.

Conclusions:
This modified Schäffer Nomogram suggests that obstructed patients are localized in grades 0c and over. Further studies are necessary for more definitive conclusions.