Methods
48 patients with symptoms of lower urinary tract dysfunction and/or prolapse were investigated by a physiotherapist and a gynaecologist. Physiotherapy assessment included vaginal palpation of levator strength based the Oxford muscle grading scale (grade 0= nothing, 1= flicker, 2= weak squeeze, 3= moderate squeeze & lift, 4=good squeeze & lift, 5=strong squeeze and lift) and perineometry (1) via an air filled vaginal sensor connected to a pressure transducer (Peritron ^TM). The patient’s muscles were graded via palpation and then evaluated via perineometry for maximum contraction pressure, average contraction pressure & hold ablity. Translabial ultrasound was carried out at rest and on pelvic floor muscle contraction. Vertical and horizontal displacement were entered into a database and the oblique or total displacement calculated. Changes in the angle g  (5) and in inclination of the proximal urethra (6) were also recorded. Both investigators were blinded against each others' results. In 2 cases palpation and perineometry were impossible due to vaginal stenosis, in another 2 only palpation was possible. This left 44 datasets for analysis. The data was analysed using Pearson’s correlation co-efficients on minitab v12.

Results
The tables show correlations between perineometry and vaginal palpation (Tab. 1), ultrasound and vaginal palpation (Tab. 2) and ultrasound and perineometry (Tab. 3). The three ultrasound parameters correlated highly (r= 0.8- 0.95) with each other.

 

Perineometry   Max. squeee pressure Average squeeze pressure         Hold

Correlation with vaginal palpation r= 0.78, p<0.001 r= 0.67, p<0.001 r= 0.31, p=0.053

Tab. 1: Correlation between perineometry and vaginal palpation (not blinded)

Ultrasound parameters Angle change (symphysis) Angle change (prox urethra)* Oblique displacement

Correlation with vaginal palpation r=-0.46, p= 0.001 r= 0.50, p= 0.002 r= 0.56, p< 0.001

Tab. 2:  Correlation between Ultrasound parameters of levator function and vaginal palpation (modified Oxford Scale, *n=40).

 

 

Ultrasound parameters         Angle change (symphysis) Angle change (prox urethra)* Oblique displacement

Perineometry (max. squeeze pressure) r=-0.38, p= 0.012 r= 0.40, p= 0.017 r= 0.46, p= 0.002

Tab. 3: Correlation between Ultrasound parameters of levator function and perineometry (*n=38).

 

Conclusion

Vaginal palpation, perineometry and ultrasound measurements of trigonal displacement all measure different aspects of a levator contraction. Perineometry assesses intravaginal pressure generated by the contraction, vaginal palpation assesses squeeze pressure and most importantly lift (grade 3 & above = ability to generate a lift via a levator contraction). Ultrasound determines changes in bladder neck geometry (lift). The best correlations were observed between perineometry and palpation, and these (non- blinded) results are comparable with literature data (7). Of the blinded comparisons, bladder neck displacement on ultrasound correlated best with vaginal palpation (r= 0.56) - both methods detect lift ability - and with perineometry (r= 0.46). Other ultrasound parameters correlated less closely.

 

Staff assessing pelvic floor function will have varying expertise and access to equipment. The methods tested here assess different aspects of levator function and all can be used in making the patient aware of her ability to contract her pelvic floor muscles. Of the ultrasound methods used, bladder neck displacement seemed to agree most closely with palpation and perineometry. It remains to be shown which of these methods correlates best with treatment success.

 

Literature

 

1 In: Pelvic floor re-education: Principles and practice, London:Springer, 1994,p. 42-48.

 

2 Br.J.Obstet.Gynaecol. 104(9):1004-1008, 1997.

 

3 Neurourol.Urodyn. 17(4):436-437, 1998.

 

4 Int.Urogynecol.J 10:S39-S40, 1999. (Abstract)

 

5 Ceska.Gynekol. 59(3):121-124, 1994.

 

6 Int.Urogynecol.J 10:S16-S17, 1999. (Abstract)