Cholecystectomy is one of the most frequently performed surgical procedures globally, primarily indicated for symptomatic gallstone disease and its related complications. With the advent of minimally invasive techniques, laparoscopic cholecystectomy has become the gold standard for gallbladder removal because it offers several advantages over conventional open surgery, including smaller incisions, reduced postoperative pain, shorter hospital stay, faster recovery, and lower postoperative morbidity [1]. Despite these benefits, a subset of cases estimated to be around 10–15%—pose significant intraoperative challenges and are categorized as “difficult cholecystectomies” [2,3]. These cases often require prolonged operative time, advanced technical skills, or even conversion to an open procedure. Factors contributing to surgical difficulty include dense pericholecystic adhesions, anatomical distortions due to chronic inflammation, empyema, Mirizzi’s syndrome, and fibrotic or contracted gallbladders. Predicting the likelihood of a difficult cholecystectomy before surgery is of great importance in surgical practice. Accurate preoperative assessment enables better preparation by the surgical team, optimal resource utilization, appropriate case selection, and reduction of intraoperative complications. Over the years, several preoperative predictive scoring systems have been proposed to identify potential difficulties in cholecystectomy. These systems generally integrate demographic, clinical, and radiological parameters such as age, sex, history of previous abdominal surgery, obesity, acute cholecystitis, gallbladder wall thickening, and pericholecystic fluid collection [4,5]. While these predictive models have demonstrated reasonable accuracy in specific populations, their reproducibility and consistency across diverse clinical settings remain uncertain. Moreover, with continual advancements in imaging modalities and deeper insights into the pathophysiological mechanisms of gallbladder disease, there is a need to reassess and refine these predictive models by incorporating novel and more reliable parameters. A difficult cholecystectomy is not only technically demanding but is also associated with a higher incidence of perioperative complications such as excessive bleeding, bile duct injury, bile leakage, wound infection, and postoperative morbidity [6]. Among these, bile duct injury remains the most dreaded complication, often leading to prolonged hospital stay, reoperations, and significant psychological and financial burden for the patient. Therefore, developing a reliable, user-friendly, and reproducible preoperative predictive model is essential to assist surgeons in anticipating potential challenges, planning appropriate operative strategies, and minimizing preventable complications. In this context, the present study was designed with the aim of developing a preoperative predictive scoring system using validated clinical and radiological parameters to identify potential difficult cholecystectomy cases and predict the likelihood of biliary injury in both open and laparoscopic approaches. The objectives of the study were to evaluate the factors contributing to difficult surgery and biliary tract injuries, to minimize the conversion rate from laparoscopic to open cholecystectomy, and to formulate a comprehensive preoperative scoring system that can aid in surgical planning, enhance operative safety, and improve overall patient outcomes.

The present study was a prospective observational study conducted in the Department of General Surgery at Princess Esra Hospital (PEH) and Owaisi Hospital & Research Centre (OHRC), both affiliated with the Deccan College of Medical Sciences (DCMS), Hyderabad. These tertiary care centers cater to a large population, providing an ideal setting for clinical and surgical research. The study was carried out over a period of 18 months with 50 sample size, allowing adequate time for patient recruitment, data collection, and analysis of operative outcomes. Inclusion Criteria All patients undergoing laparoscopic or open cholecystectomy at DCMS during the study period were considered eligible. Patients who provided informed consent and expressed willingness to participate were included in the study. Exclusion Criteria Patients were excluded if they had undergone cholecystectomy outside the institution, or if they had associated comorbid conditions such as chronic kidney disease, cardiac disease, or chronic obstructive pulmonary disease. Additionally, patients who did not provide consent or were unwilling to participate were excluded. Data Collection Data were collected prospectively using a structured proforma containing detailed clinical, biochemical, and radiological parameters. Each variable was validated against intraoperative findings to determine its correlation with surgical difficulty. Sensitivity and specificity were calculated for each parameter, and only those showing significant correlation with operative difficulty were included in the final model. Based on these observations, a new preoperative predictive scoring system was formulated. A total of 35 parameters were evaluated and assigned weighted scores, resulting in a total possible score of 42. All data were compiled into master charts for statistical analysis to assess the validity and reliability of the proposed scoring system. Preoperative Clinical Parameters Clinical variables included demographic and symptomatic factors such as age, gender, presence of fever, jaundice, palpable gallbladder, Murphy’s sign, peritonitis, PIRO scoring, body mass index (BMI), and recent history of acute cholecystitis. Each parameter was graded with scores ranging from 0 to 2 depending on severity and clinical relevance. Preoperative Imaging Parameters Radiological assessment was primarily based on ultrasonography and contrast-enhanced computed tomography (CECT). Parameters included gallbladder wall thickness, presence of gas or discontinuity in the wall, stones in the neck of the gallbladder, evidence of chronic cholecystitis, and common bile duct (CBD) dilatation with or without stones. Additional findings such as gallbladder perforation, acute cholecystitis (empyema or mucocele), and the modified CT severity index were also incorporated. Each imaging parameter was assigned a weighted score, contributing a total of 12 points. Preoperative Biochemical Investigations Laboratory parameters included total leukocyte count (TLC), C-reactive protein (CRP), procalcitonin (PCT), liver function tests (LFT), and serum albumin levels. TLC and CRP were graded according to severity, while LFT abnormalities such as elevated SGOT/SGPT and hypoalbuminemia (<3 g/dL) were assigned corresponding scores. The maximum biochemical score was 7. Intraoperative Findings Intraoperative assessment included parameters such as the status of the cystic hilum, presence of cystic node, ability to obtain the critical view of safety (CVS), level of dissection relative to Rouviere’s sulcus, condition of the common bile duct, and any ERCP interventions. Additional operative observations such as omental adhesions, duodenal or hepatic flexure involvement, cystic plate violation, gallbladder distension or decompression, intraoperative spillage, cystic artery ligation, and total operative duration were also evaluated. Each operative variable was scored objectively to correlate intraoperative difficulty with preoperative predictions. Statistical Analysis All collected data were entered into Microsoft Excel (2010) and analyzed using IBM SPSS Statistics for Windows, Version 24.0 (IBM Corp., Armonk, NY, USA). Descriptive statistics including frequency, percentage, mean, and standard deviation were used to summarize the data. Qualitative variables were expressed as frequency and percentage, while quantitative variables were represented as mean ± standard deviation. The diagnostic accuracy of each parameter was evaluated through sensitivity, specificity, and probability values to establish their predictive significance in identifying difficult cholecystectomy cases.

Table 1: Age and Gender Distribution of Patients Age Group (years) Number of Patients (N) Percentage (%) <18 3 6 18–30 18 36 31–40 12 24 41–50 9 18 51–70 5 10 >70 3 6 Gender Male 14 28 Female 36 72 Total 50 100 In the present study, a total of 50 patients undergoing cholecystectomy were evaluated. The majority of patients (36%) belonged to the 18–30 years age group, followed by 24% in the 31–40 years age group and 18% in the 41–50 years age group. A smaller proportion of patients were aged below 18 years (6%) and above 70 years (6%), while 10% were between 51 and 70 years. This indicates that cholecystectomy was most frequently performed in younger and middle-aged adults. Regarding gender distribution, females constituted the majority with 36 patients (72%), whereas males accounted for 14 patients (28%), demonstrating a clear female predominance in gallbladder disease occurrence in this cohort (Table 1). Table 2: Distribution of Patients Based on Symptoms and Clinical Signs Parameter Clinical Feature Number of Patients (N) Percentage (%) Symptoms Fever 10 20 Pain in Right Hypochondrium (RHQ) 48 96 Nausea 45 90 Vomiting 26 52 Dyspepsia 30 60 Jaundice 10 20 Dark urine and pale stools 1 2 Abdominal discomfort after consuming food 48 96 Signs Murphy’s sign 25 50 Palpable gallbladder 10 20 Charcot’s triad 2 4 Reynold’s pentad 0 0 Peritonitis 3 6 Gallbladder perforation 3 6 Tachycardia 10 20 Hypotension 1 2 Altered mental status 0 0 PIRO scoring positive 4 8 In the present study, pain in the right hypochondrium and abdominal discomfort after food intake were the most prevalent symptoms, each observed in 96% of patients. Nausea (90%) and dyspepsia (60%) were also common, while vomiting was seen in 52% of cases. Fever and jaundice were present in 20% of patients, and dark urine with pale stools was uncommon (2%). Among the clinical signs, Murphy’s sign was the most frequent (50%), followed by a palpable gallbladder (20%) and tachycardia (20%). Peritonitis and gallbladder perforation were noted in 6% each, indicating severe inflammation in a few cases. Charcot’s triad was identified in 4% of patients, while Reynold’s pentad and altered mental status were absent. A positive PIRO score was noted in 8% of cases, reflecting systemic inflammatory response in select patients. Overall, these findings highlight that most patients presented with classic biliary symptoms and localized signs, with a minority showing systemic or complicated presentations (Table 2). Table 3: Distribution of Patients Based on Duration of Acute Cholecystitis and Gallbladder Imaging Findings Parameter Finding / Category Number of Patients (N) Percentage (%) Duration of Acute Cholecystitis Yes (<10 days) 15 30 Yes (>10 days) 12 24 No 23 46 Gallbladder Findings Empyema 8 16 Mucocele 7 14 Imaging Features GB wall thickness < 2 mm 34 68 GB wall thickness > 3 mm 12 24 Gas in gallbladder wall 1 2 Break in GB wall 3 6 Stone in neck of gallbladder 16 32 Total 50 100 Among the 50 patients studied, 54% presented with a history of acute cholecystitis, of which 30% had symptoms for less than 10 days and 24% for more than 10 days, whereas 46% did not have a recent episode of acute cholecystitis. On imaging and intraoperative assessment, empyema was observed in 16% of cases and mucocele in 14%, indicating that a significant subset of patients had chronic or complicated gallbladder disease. Ultrasonographic evaluation revealed that the majority (68%) had gallbladder wall thickness less than 2 mm, while 24% exhibited wall thickening greater than 3 mm, suggesting inflammation. Additional features such as gas within the gallbladder wall (2%) and wall discontinuity or break (6%) were noted in a small number of patients, often correlating with severe inflammation or impending perforation. Stones impacted in the neck of the gallbladder were seen in 32% of cases, which are recognized predictors of operative difficulty. Overall, these findings highlight that imaging characteristics such as wall thickening, stone impaction, and presence of empyema or mucocele serve as important preoperative indicators of difficult cholecystectomy (Table 3). CRP levels were found to be less than 6 mg/L in 34 patients (68%). In 11 patients (22%), CRP values ranged between 6 to 10 mg/L. The remaining 5 patients (10%) had CRP levels greater than 10 mg/L. Procalcitonin levels were within the normal range in 39 patients (78%). Elevated procalcitonin levels were noted in 11 patients (22%). Liver function tests were normal in 38 patients (76%). A total of 7 patients (14%) had elevated total bilirubin levels with normal liver enzymes. In 5 patients (10%), both total bilirubin and liver enzymes were elevated. Serum albumin levels were found to be within the normal range in 47 patients (94%). Hypoalbuminemia, defined as serum albumin less than 3 g/dL, was observed in 3 patients (6%). Table 4: Distribution of patients based on intraoperative gallbladder findings Intraoperative status Number of patients (N) Percentage (%) Hilum Virgin 37 74 Frozen partial cholecystectomy 2 4 Frozen fundus-first laparoscopic cholecystectomy 3 6 Frozen: Laparoscopy converted to open cholecystectomy 5 10 Frozen: Open cholecystectomy 3 6 Total 50 100 Hilum virgin gallbladder was observed in 37 patients (74%). Frozen partial cholecystectomy was performed in 2 patients (4%). Frozen fundus-first laparoscopic cholecystectomy was done in 3 patients (6%). Conversion from laparoscopy to open cholecystectomy occurred in 5 patients (10%), and 3 patients (6%) underwent open cholecystectomy directly (Table 4). Table 5: Intraoperative Findings Related to Surgical Anatomy and Safety (n = 50) Parameter Category / Observation n (%) Gallbladder Hilum Status Virgin 37 (74) Frozen (partial / fundus-first / converted / open) 13 (26) Cystic Node Positive 19 (38) Negative 31 (62) Critical View of Safety (CVS) Achieved 47 (94) Not defined (partial / bile duct injury) 3 (6) Level of Dissection at Rouviere’s Sulcus Above 48 (96) Below 2 (4) Intraoperative assessment revealed that 74% of patients had a normal or “virgin” hilum, while 26% exhibited frozen or fibrotic hilum requiring modified dissection or conversion to open cholecystectomy. The cystic node was identified in 38% of patients. The critical view of safety (CVS) was achieved in the majority (94%), whereas 6% had incomplete visualization or bile duct injury. Dissection above Rouviere’s sulcus was maintained in 96% of cases, reflecting adherence to safe surgical principles (Table 5). Table 6: Summary of Key Intraoperative Findings (n = 50) Parameter Observation / Category n (%) Surgical Approach Virgin hilum 37 (74) Frozen hilum (partial / fundus-first / converted / open) 13 (26) Cystic Node Positive 19 (38) Critical View of Safety (CVS) Achieved 47 (94) Not defined / bile duct injury 3 (6) Level of Dissection at Rouviere’s Sulcus Above 48 (96) Below 2 (4) Common Bile Duct (CBD) Normal 36 (72) Dilated (explored / ERCP / no procedure) 14 (28) Gallbladder Condition Clean 29 (58) Omental or surrounding adhesions 21 (42) Adjacent Organ Involvement Duodenal adhesions 7 (14) Hepatic flexure adhesions 1 (2) Cystic Plate Intact dissection 48 (96) Violated 2 (4) Gallbladder Distension Not decompressed 42 (84) Decompressed (pus / mucocele) 8 (16) Intraoperative Spillage Yes 14 (28) Cystic Artery Safely ligated 48 (96) Duration of Surgery < 1 hour 42 (84) > 2 hours 8 (16) Among 50 patients, 74% had a virgin hilum, while 26% exhibited frozen or fibrotic hilum requiring modified dissection or conversion to open surgery. The critical view of safety was achieved in 94% of cases, with only 2% experiencing bile duct injury. Safe dissection above Rouviere’s sulcus was maintained in 96% of cases. The common bile duct was normal in most patients (72%), while 28% showed dilatation, some requiring exploration or ERCP. Omental adhesions were seen in 42%, and duodenal or hepatic flexure adhesions were rare. Intraoperative spillage occurred in 28% of cases, but the cystic artery was safely ligated in 96%. Most surgeries (84%) were completed within one hour, demonstrating overall procedural efficiency despite occasional difficult anatomy (Table 6). The graph shows the relationship between the preoperative score and the probability of encountering a difficult cholecystectomy. The x-axis represents the preoperative score, while the y-axis indicates the approximate risk percentage of difficult surgery. The curve demonstrates a direct positive correlation as the preoperative score increases, the probability of a difficult surgery rises proportionally. Patients with a low preoperative score (0–5) have a minimal risk of surgical difficulty (below 10%). As the score increases to around 10–15, the probability rises sharply to nearly 40–60%, indicating moderate risk. Scores beyond 20 are associated with a high likelihood of difficult cholecystectomy, reaching 80–90% at higher values

In the present study, acute cholecystitis was most prevalent among patients aged 19–30 years (36%), suggesting a predominance in young adults, likely due to hormonal, lifestyle, and metabolic influences. Elevated estrogen levels increase biliary cholesterol saturation, while progesterone reduces gallbladder motility, favoring gallstone formation the primary etiology of acute cholecystitis. The low incidence in pediatric (<18 years, 6%) and elderly (>70 years, 6%) groups highlights age-dependent variations, with hemolytic disorders or congenital causes implicated in younger patients and decreased motility or comorbidities in the elderly. These findings align with earlier studies (3). A clear female predominance (72%) was observed, consistent with established epidemiological trends. Hormonal factors particularly estrogen-induced cholesterol supersaturation and progesterone-mediated gallbladder stasis contribute to this gender difference, especially during reproductive years. Additional risk enhancers include pregnancy, oral contraceptive use, obesity, and sedentary lifestyle, as supported by Agrawal N et al., Bourgouin S et al., (7, 8). Clinically, right hypochondrial pain was the most frequent symptom (96%), followed by nausea (90%) and vomiting (52%), reflecting typical inflammatory and autonomic responses. Dyspepsia (60%), fever (20%), and jaundice (20%) indicate systemic inflammation or biliary obstruction, comparable to observations by Hussain A et al., (9). Murphy’s sign was positive in 50% of cases, reinforcing its diagnostic value, while palpable gallbladder (20%), peritonitis (6%), and perforation (6%) represented complications of delayed presentation. Charcot’s triad was rare (4%), suggesting limited biliary sepsis in this cohort. Most patients (76%) presented within 10 days of symptom onset, correlating with timely surgical intervention, while prolonged symptoms (>10 days in 24%) were associated with complications such as empyema or perforation. Gallbladder wall thickening (>3 mm) was observed in 24% and stones impacted in the neck in 32%, reinforcing the inflammatory and obstructive pathology of acute cholecystitis. Empyema (16%) and mucocele (14%) represented advanced disease stages, while gas in the wall (2%) indicated emphysematous cholecystitis an emergency condition. These imaging findings were comparable to the results reported by earlier authors (10, 11). Regarding biliary anatomy, 68% of patients had a normal common bile duct (CBD), while 16% demonstrated choledocholithiasis and 8% showed CBD dilatation without stones. Choledochal cysts (8%) were also detected, emphasizing the diagnostic importance of imaging. These findings corroborate earlier works (12). Biochemical markers mirrored disease severity: leukocytosis (>15,000) in 26%, elevated CRP (>10 mg/L) in 10%, and increased procalcitonin in 22% confirmed active inflammation or sepsis. Elevated bilirubin (24%) suggested biliary obstruction, while hypoalbuminemia (6%) reflected systemic illness. These trends agree with prior observations by Tiwari MM et al. and colleagues. Intraoperatively, the critical view of safety was achieved in 94%, reflecting adherence to safe surgical principles. Conversion to open surgery (16%) occurred in cases with frozen hilum, empyema, or dense adhesions. Adhesions to omentum (42%) and intraoperative hemodynamic changes (28%) emphasized surgical and anesthetic challenges. Most operations (84%) were completed within one hour, while prolonged durations correlated with complex pathology, aligning with findings from Schrenk P et al (13). The study also introduced a comprehensive preoperative and intraoperative predictive scoring system for assessing cholecystectomy difficulty. The preoperative score (maximum 35) incorporated demographics, clinical features, imaging, and biochemical parameters, while the intraoperative component (maximum 13) quantified technical complexity. Based on cumulative scores, patients were classified into three risk groups: very low (0–6), low-to-moderate (7–14), and moderate-to-high (15–30). Patients in the very low-risk group had smooth laparoscopic outcomes with minimal complications (<5% conversion). The low-to-moderate group showed mild to moderate inflammation or adhesions, with a 10–40% conversion risk, requiring greater vigilance. The moderate-to-high-risk group exhibited advanced disease (e.g., empyema, perforation, dense adhesions) and systemic inflammatory response, with ≥60% conversion or complication likelihood. Stratification thus enabled targeted perioperative planning, senior surgeon involvement, and improved patient counseling.

In the present study, acute cholecystitis was most prevalent among patients aged 19–30 years (36%), suggesting a predominance in young adults, likely due to hormonal, lifestyle, and metabolic influences. Elevated estrogen levels increase biliary cholesterol saturation, while progesterone reduces gallbladder motility, favoring gallstone formation the primary etiology of acute cholecystitis. The low incidence in pediatric (<18 years, 6%) and elderly (>70 years, 6%) groups highlights age-dependent variations, with hemolytic disorders or congenital causes implicated in younger patients and decreased motility or comorbidities in the elderly. These findings align with earlier studies (3). A clear female predominance (72%) was observed, consistent with established epidemiological trends. Hormonal factors particularly estrogen-induced cholesterol supersaturation and progesterone-mediated gallbladder stasis contribute to this gender difference, especially during reproductive years. Additional risk enhancers include pregnancy, oral contraceptive use, obesity, and sedentary lifestyle, as supported by Agrawal N et al., Bourgouin S et al., (7, 8). Clinically, right hypochondrial pain was the most frequent symptom (96%), followed by nausea (90%) and vomiting (52%), reflecting typical inflammatory and autonomic responses. Dyspepsia (60%), fever (20%), and jaundice (20%) indicate systemic inflammation or biliary obstruction, comparable to observations by Hussain A et al., (9). Murphy’s sign was positive in 50% of cases, reinforcing its diagnostic value, while palpable gallbladder (20%), peritonitis (6%), and perforation (6%) represented complications of delayed presentation. Charcot’s triad was rare (4%), suggesting limited biliary sepsis in this cohort. Most patients (76%) presented within 10 days of symptom onset, correlating with timely surgical intervention, while prolonged symptoms (>10 days in 24%) were associated with complications such as empyema or perforation. Gallbladder wall thickening (>3 mm) was observed in 24% and stones impacted in the neck in 32%, reinforcing the inflammatory and obstructive pathology of acute cholecystitis. Empyema (16%) and mucocele (14%) represented advanced disease stages, while gas in the wall (2%) indicated emphysematous cholecystitis an emergency condition. These imaging findings were comparable to the results reported by earlier authors (10, 11). Regarding biliary anatomy, 68% of patients had a normal common bile duct (CBD), while 16% demonstrated choledocholithiasis and 8% showed CBD dilatation without stones. Choledochal cysts (8%) were also detected, emphasizing the diagnostic importance of imaging. These findings corroborate earlier works (12). Biochemical markers mirrored disease severity: leukocytosis (>15,000) in 26%, elevated CRP (>10 mg/L) in 10%, and increased procalcitonin in 22% confirmed active inflammation or sepsis. Elevated bilirubin (24%) suggested biliary obstruction, while hypoalbuminemia (6%) reflected systemic illness. These trends agree with prior observations by Tiwari MM et al. and colleagues. Intraoperatively, the critical view of safety was achieved in 94%, reflecting adherence to safe surgical principles. Conversion to open surgery (16%) occurred in cases with frozen hilum, empyema, or dense adhesions. Adhesions to omentum (42%) and intraoperative hemodynamic changes (28%) emphasized surgical and anesthetic challenges. Most operations (84%) were completed within one hour, while prolonged durations correlated with complex pathology, aligning with findings from Schrenk P et al (13). The study also introduced a comprehensive preoperative and intraoperative predictive scoring system for assessing cholecystectomy difficulty. The preoperative score (maximum 35) incorporated demographics, clinical features, imaging, and biochemical parameters, while the intraoperative component (maximum 13) quantified technical complexity. Based on cumulative scores, patients were classified into three risk groups: very low (0–6), low-to-moderate (7–14), and moderate-to-high (15–30). Patients in the very low-risk group had smooth laparoscopic outcomes with minimal complications (<5% conversion). The low-to-moderate group showed mild to moderate inflammation or adhesions, with a 10–40% conversion risk, requiring greater vigilance. The moderate-to-high-risk group exhibited advanced disease (e.g., empyema, perforation, dense adhesions) and systemic inflammatory response, with ≥60% conversion or complication likelihood. Stratification thus enabled targeted perioperative planning, senior surgeon involvement, and improved patient counseling.

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