Regeneration of uterine cervix at 6 months after large loop excision of the transformation zone for cervical intraepithelial neoplasia.

OBJECTIVE: To sonographically investigate cervical regeneration 6 months after large loop excision of the transformation zone (LLETZ) conisation for cervical intraepithelial neoplasia (CIN) pathology.
DESIGN: Prospective observational study.
SETTING: University Hospital setting. POPULATION: Women having LLETZ conisation for intraepithelial lesions in response to abnormal Papanicolaou smears or colposcopic findings.
METHODS: Cervical dimensions were estimated before conisation and at 6 months with three-dimensional sonography and use of vocal™ software. Cone depth was measured using a ruler before fixation, and cone volume was measured using a volumetric tube and the fluid displacement technique. Cervical regeneration was sonographically estimated. MAIN OUTCOME MEASURES: Correlation of cervical volume regeneration with percentage of initial cervical volume excised and remaining cervical tissue immediately after conisation.
RESULTS: A cohort of 112 women were initially recruited over a 2-year period and 73 women presented for ultrasound follow up at 6 months. Multivariate linear regression analysis showed that for women matched for age and initial cervical volume, if cervical volume excised was increased by 1% then regeneration of tissue deficit at the cervical crater was reduced by 1.37%. There also seemed to be a cutoff point suggesting that when >14% of initial cervical volume was excised, the tissue deficit at the cervical crater at 6 months was restored by <75% and there was >25% of remaining tissue deficit.
CONCLUSIONS: Cervical regeneration at 6 months after excision is dependent on the percentage of initial cervical volume excised and on the remaining cervical tissue immediately after conisation. The greater the cone and the less cervical tissue remaining, the less the degree of cervical regeneration achieved.