European Journal of Cardiovascular Medicine

Inguinal hernia remains one of the most frequently encountered surgical conditions globally, affecting both pediatric and adult populations. Timely and accurate preoperative assessment is essential not only for confirming diagnosis but also for delineating hernia sac contents, guiding surgical planning, and anticipating complications. In this context, ultrasonography (USG) has emerged as a reliable, cost-effective, and non-invasive diagnostic tool with growing clinical relevance.

In pediatric patients, identifying a patent processus vaginalis is crucial in preventing metachronous contralateral hernias, and ultrasonography has shown high reliability in this regard [1]. Beyond diagnosis, its role has expanded to the detection of contralateral occult hernias in patients presenting with unilateral symptoms, helping to avoid missed pathology during surgery [2]. While modalities such as computed tomography (CT) with the Valsalva maneuver offer high sensitivity in the characterization of hernias, they are often limited by radiation exposure and accessibility, especially in resource-limited settings [3].

Ultrasound, in contrast, provides dynamic, real-time imaging, with the advantage of visualizing reducibility, peristalsis, and vascularity of the herniated contents [4]. Moreover, it plays a pivotal role in the pediatric subset, where the decision to explore the contralateral side is often debated. A systematic review by Ron et al. underscored the significance of predictive imaging tools to assess the risk of developing a metachronous hernia, reinforcing the value of preoperative sonography [5].

Aim and Objectives:
The present study aimed to evaluate the role of preoperative ultrasonography in detecting the contents of inguinal hernia sacs and to assess its correlation with intraoperative findings in a retrospective cohort of patients undergoing elective hernia repair.

Study Design and Setting:
This retrospective observational study was conducted in the Department of General Surgery at RVM Institute of Medical Sciences, Telangana, India, over a 12-month period from January 2024 to December 2024.

Study Population:
The study included 100 patients clinically diagnosed with inguinal hernia who underwent both preoperative ultrasonographic evaluation and elective surgical repair during the study period. All patients were aged ≥18 years and provided complete medical records.

Inclusion Criteria:

• Patients with clinically diagnosed unilateral or bilateral inguinal hernia
• Patients who underwent preoperative ultrasonography and elective hernia surgery
• Availability of complete ultrasonographic and intraoperative documentation

Exclusion Criteria:

• Recurrent inguinal hernia
• Incarcerated or strangulated hernias requiring emergency intervention
• Incomplete clinical or imaging records
• Patients with previous pelvic or groin surgeries

Data Collection:
Data were extracted retrospectively from hospital records, including demographic details, ultrasonographic findings (hernia side, contents, reducibility), and intraoperative findings (type of sac contents confirmed during surgery). All ultrasonographic assessments were performed using high-frequency (7.5–10 MHz) linear transducers by experienced radiologists blinded to surgical outcomes.

Outcome Measures:
The primary outcome was to determine the correlation between preoperative ultrasonographic identification of hernia sac contents and intraoperative findings. Diagnostic parameters including sensitivity, specificity, and concordance rate were calculated for different sac contents using intraoperative findings as the gold standard.

Statistical Analysis:
Data were entered in Microsoft Excel and analyzed using SPSS version 26.0 (IBM Corp., Armonk, NY, USA). Descriptive statistics were presented as frequencies and percentages. Diagnostic accuracy of ultrasonography for each sac content was calculated in terms of sensitivity, specificity, and overall concordance. Cohen’s Kappa coefficient was used to assess agreement between USG and intraoperative findings. A p-value < 0.05 was considered statistically significant.

Ethical Considerations:

The study protocol was approved by the Institutional Ethics Committee of RVM Institute of Medical Sciences. Patient confidentiality was strictly maintained, and no identifiable information was used in analysis or reporting.

A total of 100 patients clinically diagnosed with inguinal hernia and who underwent both preoperative ultrasonography (USG) and intraoperative evaluation were retrospectively analyzed. The demographic characteristics of the study population are summarized in Table 1. The majority of patients were male (92%), with the highest prevalence in the 41–60 year age group (44%). Right-sided hernias were more common (62%), followed by left-sided (35%) and bilateral hernias (3%).

Table 1: Demographic Profile of Patients (n = 100)

Preoperative ultrasonography successfully identified hernial sac contents in 97% of patients, with omentum being the most frequently detected structure (46%), followed by bowel loops (38%) and fluid-filled sacs (7%). Urinary bladder involvement was noted in 4 cases, while undescended testes were identified in 2 pediatric patients. In 3 cases (3%), no sac contents were visualized sonographically (Table 2).

Table 2: Preoperative Ultrasonographic Findings of Hernial Sac Contents (n = 100)

Intraoperative exploration confirmed the presence of omentum in 48% and bowel loops in 36% of cases. Fluid collection and urinary bladder involvement were observed in 6% and 3%, respectively. Intraoperatively empty sacs were found in 5% of cases. The intraoperative findings are detailed in Table 3.

Table 3: Intraoperative Findings of Hernial Sac Contents (n = 100)

The diagnostic performance of ultrasonography was evaluated by comparing preoperative and intraoperative findings, as shown in Table 4.

Table 4: Correlation Between Ultrasonographic and Intraoperative Findings

Ultrasonography demonstrated high sensitivity and specificity in identifying the contents of the hernial sac. For omental herniation, the sensitivity was 91.7% and specificity 97.9%, while for bowel loops, the sensitivity and specificity were 94.4% and 95.3%, respectively. Urinary bladder and undescended testes were correctly identified in all respective cases, yielding 100% sensitivity. The overall diagnostic concordance rate between ultrasonographic and intraoperative findings was 93%, with a high degree of agreement (κ = 0.87).

These results underscore the reliability of preoperative ultrasonography not only in confirming the diagnosis of inguinal hernia but also in accurately predicting the nature of the sac contents, thereby facilitating operative planning.

The present study reaffirms the diagnostic utility of preoperative ultrasonography (USG) in evaluating inguinal hernia sac contents, demonstrating a strong correlation with intraoperative findings. With an overall concordance of 93% and substantial agreement (κ = 0.87), the results support routine use of USG not only for hernia diagnosis but also for detailed preoperative anatomical mapping.

The predominance of male patients and the higher frequency of right-sided hernias in our cohort are consistent with established epidemiological trends. Similar patterns have been observed in Indian and global data, often attributed to the anatomical predisposition and increased intra-abdominal pressures associated with male physiology and occupational strain [8].

Ultrasonography in our study showed high sensitivity and specificity in identifying both omental (91.7%) and bowel loop (94.4%) herniation. These findings are in line with the results of Ridha et al., who reported a positive predictive value of 96.6% for USG in identifying inguinal hernias, affirming its clinical reliability in real-world settings [9]. Additionally, the accurate detection of urinary bladder involvement in all cases (100% sensitivity) emphasizes the role of imaging in preventing iatrogenic injuries, especially in elderly males or in cases of sliding hernias.

While a small proportion of false negatives and false positives were encountered, these are likely due to patient-related variables such as obesity, transient sac reducibility, and operator dependency. Nevertheless, our findings align with recent studies that have shown ultrasound to retain high diagnostic accuracy even in challenging scenarios such as pediatric, female, and obese patients [6,7].

Although computed tomography (CT) offers superior delineation in complex or occult cases, its routine use is limited by cost, accessibility, and radiation exposure. Katoh et al. highlighted the value of preoperative prone CT in predicting difficult hernias undergoing transabdominal preperitoneal (TAPP) repair, but its role remains adjunctive rather than primary, particularly in resource-limited settings [10].

Importantly, USG also allows for the characterization of rare hernia contents such as ovary or undescended testis, which has significant implications in female and pediatric populations. Prodromidou et al. demonstrated the importance of imaging in identifying ovarian hernias to prevent misdiagnosis and surgical complications [7].

From a surgical planning perspective, precise knowledge of hernia sac contents preoperatively can inform decisions regarding the surgical approach—open versus laparoscopic, unilateral versus bilateral—and anticipate potential intraoperative risks. The present study, conducted in a tertiary care setting in India, supports the integration of standardized ultrasonographic assessment protocols into routine preoperative workflows.

Limitations of the present study include its retrospective design, single-center setting, and dependence on the quality of archived imaging reports. Prospective studies with standardized USG protocols and inter-observer variability assessments are warranted to further validate these findings.

This retrospective observational study reinforces the diagnostic accuracy of preoperative ultrasonography in evaluating inguinal hernia sac contents. With a high concordance rate (93%) and excellent sensitivity and specificity across most sac components, ultrasonography proves to be a reliable, non-invasive, and cost-effective modality for preoperative assessment. Accurate identification of omentum, bowel loops, urinary bladder, and other structures allows surgeons to anticipate intraoperative challenges, refine surgical planning, and potentially minimize complications. Given its accessibility and reproducibility, routine incorporation of ultrasonographic evaluation in the preoperative workup of inguinal hernias is strongly recommended, especially in resource-limited settings where advanced imaging modalities may not be available.

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