Obstetric anal sphincter injuries (OASIS) are third and fourth-degree perineal injuries occurring during delivery(1). Limited studies exist on Introital Ultrasound for detecting anal sphincter injuries as an alternative to endoanal ultrasound. This study aimed to assess the feasibility and diagnostic accuracy of Introital Ultrasound in detecting anal sphincter injuries.
AIM 
To Evaluate the Role of Introital Ultrasound in Detecting Obstetric anal sphincter injuries.

Primary Objective: 
To determine incidence of OASIS in postpartum women using Introital Ultrasound.
Secondary Objective:
•	Assess the benefit of Kegel exercises in patients with anal sphincter injuries.
•	Evaluate the quality of life using the Pelvic Floor Disability Index (PFDI-20) score.

This prospective observational study was conducted at a tertiary care centre in New Delhi for one year.
Sample Size: 150 patients (100 normal vaginal deliveries, 25 instrumental deliveries, 25 caesarean sections).
INCLUSION CRITERIA:
•	 18 to 45 years
•	No history of anal incontinence.
•	All grades of perineal tear 
EXCLUSION CRITERIA:
•	Prior pelvic organ prolapse.
•	Neurological diseases 
•	Patients  unwilling to follow-up.
METHODOLOGY 
150 patients underwent Introital Ultrasound (Voluson E8 and E10 at 4-9 MHz),  48-72 hours post-delivery to assess anal sphincter injuries. All patients were advised Kegel exercises. PFDI-20 scores were recorded postpartum and at a 6-week follow-up, along with repeat Introital Ultrasound.

In our study out of 10 patients of sphincter discontinuity, 9 were primigravida. 2 had normal vaginal delivery and 8 had instrumental delivery. The mean age of pregnant women  with sphincter discontinuity was 27.6 +/- 4.1years  and with  intact sphincter  was 28.6 +/- 4.6 which was statistically insignificant. The mean duration of second stage of labour in patients with sphincter discontinuity was 87.5 minutes and in patients with intact sphincter was 30 minutes. The mean birth weight was 2760gm in participants with intact sphincter and 3062 in group with sphincter discontinuity with no significant difference in risk of OASIS. 
Figure 1-  shows Table 1,2,3 depicting Primary outcome, Effect of kegel's exercise and PFDI 20 scores repectively.

Introital Ultrasound increased the detection of sphincter injuries from 1.3% (clinical diagnosis) to 6.6%. After 6 weeks, only 2 patients showed residual injury, while 8 improved with Kegel exercises.
In a study by Ozyurt et.al  in 2015 (2) including 201 primigravida who delivered vaginally to evaluate the benefit of ultrasound using a transvaginal probe  after vaginal delivery to the standard clinical examination identified sphincter injury in 30 of 201 patients (15 %). Seven injury patients (3.5 %) were determined by clinical examination and 23 injury patients (11.5 %) were identified  after ultrasonography  
Annika et.al in 2019 (3) conducted  a cross-sectional study of 250 consecutive women who had sustained OASIs and undergone primary repairs of the anal sphincter and stated that Endoanal ultrasound imaging remains the most accurate diagnostic imaging modality.

Introital Ultrasound effectively detects occult OASIS missed during delivery. Early pelvic floor exercises significantly improve outcomes in patients with sphincter injuries.

Balachandran AA, Wong KKW, Thakar R. Risk factors for and management of obstetric anal sphincter injury. Obstetrics Gynaecology & Reproductive Medicine. 2022 May 12;32(6):105–9.
Ozyurt S, Aksoy H, Gedikbasi A, Yildirim G, Aksoy U, Acmaz G, et al. Screening occult anal sphincter injuries in primigravid women after vaginal delivery with transperineal use of vaginal probe: a prospective, randomized controlled trial. Archives of Gynecology and Obstetrics. 2015 Apr 9;292(4):853–9.
Taithongchai A, Van Gruting IMA, Volløyhaug I, Arendsen LP, Sultan AH, Thakar R. Comparing the diagnostic accuracy of 3 ultrasound modalities for diagnosing obstetric anal sphincter injuries. American Journal of Obstetrics and Gynecology 2019 Apr 11;221(2):134.e1-134.e9.