UOG Journal Club: December 2012

Diagnosis of levator avulsion injury: a comparison of three methods

HP Dietz, F Moegni, KL Shek Volume 40, Issue 6, Date: December 2012, pages 693 –698

Journal Club slides prepared by Dr Tommaso Bignardi (UOG Editor for Trainees)

Background

• Levator avulsion is common after vaginal delivery and is strongly associated with prolapse and prolapse recurrence after reconstructive surgery • Levator avulsion can be diagnosed by vaginal palpation, 3D/4D translabial ultrasound or magnetic resonance imaging (MRI) • With the 3D ultrasound technique, data can be analysed as rendered volumes or else tomographic multislice imaging

Diagnosis of levator avulsion injury: a comparison of three methods

Dietz et al., UOG 2012

The aim of this study was to compare assessment by digital palpation and two ultrasound methods, one using rendered volumes and the other multislice imaging, for the diagnosis of levator avulsion

Diagnosis of levator avulsion injury: a comparison of three methods

Dietz et al., UOG 2012

Patients and Methods

• 266 women seen at a tertiary urogynecological unit • Each woman underwent an interview, vaginal examination and 3D/ 4D translabial ultrasound

retrospective offline analysis of ultrasound volumes, blinded against clinical data, using two techniques rendered volumes tomographic ultrasound imaging (TUI)

Agreement was evaluated between the ultrasound techniques and findings on digital palpation The results were finally related to symptoms and signs of pelvic organ prolapse

Diagnosis of levator avulsion injury: a comparison of three methods

Dietz et al., UOG 2012

Vaginal palpation

The index finger is placed parallel to the urethra, with fingertip at the bladder neck.

The fingertip is turned towards the inferior pubic ramus, whilst the patient is asked to contract the pelvic floor. The gap between urethra and muscle should be about one fingerbreadth. If no contractile tissue is palpated there will be room for two or more fingers between urethra and pelvic sidewall, and a diagnosis of avulsion is made.

Diagnosis of levator avulsion injury: a comparison of three methods

Dietz et al., UOG 2012

Rendered volumes

• Obtained on maximal pelvic floor contraction • Slice thickness of between 1.5 and 2.5 cm • Plane of minimal hiatal dimensions included in the ‘region of interest’

Diagnosis of levator avulsion injury: a comparison of three methods

Dietz et al., UOG 2012

Tomographic ultrasound imaging (TUI)

• Obtained during maximum pelvic floor contraction • Set of 8 slices in the axial plane at intervals of 2.5mm

• Taken from 5mm caudad to 2.5mm cephalad of the plane of minimal hiatal dimensions

Diagnosis of levator avulsion injury: a comparison of three methods

Dietz et al., UOG 2012

Results:

Agreement between methods Methods compared Agreement (%) Palpation versus rendered volume Rendered volume versus TUI Palpation versus TUI TUI, tomographic ultrasound imaging.

86 80 87 Cohen’s kappa (95% CI) 0.43 (0.32

–0.53) 0.35 (0.26

–0.44) 0.56 (0.48

–0.62) CI, confidence interval

Diagnosis of levator avulsion injury: a comparison of three methods

Dietz et al., UOG 2012

Method

Palpation Rendered volume

Results:

Association with symptoms and signs of prolapse Tomographic ultrasound

Symptoms of prolapse

χ2 = 39.8

P < 0.001† χ2 = 25.8

P< 0.001* χ2 = 13.8

P< 0.001

Significant prolapse (POPQ stage 2+) Maximum bladder descent on ultrasound

χ2 = 91.1

P < 0.001† χ2 = 64.3

P< 0.001* χ2 = 58.3

P< 0.001

t = 4.22

P< 0.001

t = 2.73

P= 0.007*

t = 3.78

P< 0.001

Maximum hiatal area on Valsalva

t = -6.92

P< 0.001*

t = -3.46

P< 0.001**

t = -7.04

P< 0.001*

n=266

except for

*n=259

and

**n=252.

All findings were blinded against each other, except for those marked with †.

Diagnosis of levator avulsion injury: a comparison of three methods

Dietz et al., UOG 2012

Key findings

• Vaginal palpation, rendered ultrasound volumes and multislice imaging all seem to be moderately repeatable and they correlate moderately well with each other • Findings for all three methods are significantly associated with symptoms, signs and ultrasound findings of female pelvic organ prolapse

Diagnosis of levator avulsion injury: a comparison of three methods

Dietz et al., UOG 2012

Limitations

• Retrospective analysis • Women with previous pelvic surgery not excluded • Palpation data obtained by senior author not consistently blinded to history and other clinical findings • These three methods need validation in other populations

Diagnosis of levator avulsion injury: a comparison of three methods

Dietz et al., UOG 2012

Discussion points

• Should the study of levator avulsion form part of routine investigations for women presenting with symptoms and/or signs of pelvic prolapse? • What are the clinical implications of diagnosing avulsion, especially prior to prolapse surgery?

• Do the data presented in the study demonstrate the superiority of ultrasound techniques over digital palpation for diagnosing levator avulsion?

• How do the techniques investigated compare against MRI assessment?

• How can we identify and counsel women at higher risk of recurrence after pelvic reconstructive surgery?