Advancements in laparoscopic surgery have significantly transformed the field of minimally invasive procedures, offering improved outcomes, reduced recovery times, and enhanced visualization during surgery.¹ In particular, the role of imaging modalities has become pivotal in refining surgical precision and optimizing intraoperative decision-making.² Conventional white light imaging (WLI) has long been the standard for visualizing anatomical structures during laparoscopic procedures. However, its limitations in identifying subtle tissue contrasts and vascular patterns have spurred interest in alternative imaging modalities.³

Yellow enhancement (YE) imaging is an emerging technology designed to enhance the visualization of critical structures by amplifying contrast and improving differentiation between tissues.⁴ This imaging modality is particularly relevant in surgeries for conditions such as cholelithiasis and inguinal hernia, where accurate visualization of anatomical landmarks, including the biliary anatomy and hernial defects, is crucial to minimize complications and ensure surgical success.

This cross-sectional study aims to evaluate the role of  Yellow Enhancement (YE) Imaging versus White Light Imaging (WLI) in improving intraoperative visualization during laparoscopic cholecystectomy and inguinal hernia repair.

The present study is a hospital-based cross-sectional study conducted at Vishesh Jupiter Hospital, Indore, over a period of eighteen months (from July, 2023 to December, 2024).

The study included patients aged above 18 years of both genders who underwent laparoscopic cholecystectomy or inguinal hernia repair, with complete intraoperative imaging records for both WLI and YE. Only patients who provided consent to participate in the study were included.

Patients who underwent open surgeries, had incomplete imaging or operative records, had prior extensive abdominal surgeries leading to altered anatomy, or had severe systemic comorbidities contraindicating laparoscopic surgery were excluded from the study.

Sample Size Calculation

The sample size was calculated assuming a proportion of 50% (maximum variability) for the better visualization rate of YE over WLI, as no robust studies on this specific topic were identified during the study planning phase.

Using the formula for sample size estimation in cross-sectional studies:

Where:

Z=1.96 (for 95% confidence level),

p=0.5 (assumed proportion),

d=0.1 (margin of error, 10%).

Thus, the calculated sample size is 96, which was rounded up to 100 cases.

Sampling Method

A consecutive sampling method was employed, where all eligible patients who underwent laparoscopic cholecystectomy or inguinal hernia repair during the study period were included until the desired sample size of 100 cases was reached.

Method of Data Collection

Data for present study was collected using a predesigned semi-structured proforma. Visualization parameters and surgeon-reported outcomes, were assessed using a Likert scale ranging from 1 to 5, where 1=poor, 2=fair, 3 =good, 4=very good, and 5=excellent. Data collection was carried out through direct observation during surgeries and surgeon feedback immediately afterward.

Statistical Analysis

For statistical analysis, descriptive statistics were used to summarize demographic and procedural data. Comparative analysis of visualization quality between WLI and YE was performed using  independent t-test to analyze Likert scale scores. A p-value of <0.05 was considered statistically significant.

Table-1: Demographic characteristics of study participants

Table-1 summarizes the demographic characteristics of the study population. The total sample consisted of 100 patients, with a slight male predominance (55 males and 45 females). The mean age of participants was 42.3±7.8 years, indicating a middle-aged population. 20% of the participants had hypertension, and 15% had diabetes. 57 cases underwent cholecystectomy and 43 cases underwent inguinal hernia repair. The mean duration of surgeries was 85.4±14.7 minutes.

Table-2: Comparison of intraoperative visualization clarity of anatomical structures between WLI and YE imaging [scoring based on Likert Scale:1-5]

Table-2 presents the comparison of intraoperative visualization clarity between WLI and YE for key anatomical features. The clarity of vascular structures under YE scored significantly higher (4.8 ± 0.03) compared to WLI (3.2 ± 0.5), with a p-value of <0.001. Similarly, YE outperformed WLI in fat differentiation (4.7 ± 0.04 vs. 2.9 ± 0.6) and the identification of avascular planes (4.9 ± 0.02 vs. 3.1 ± 0.5), both with p-values of <0.001. The statistical significance of these findings was determined through independent t-test.

Table-3: Surgeon-reported outcomes comparing WLI and YE imaging [scoring based on Likert Scale:1-5]

Table-3 depicts that Surgeon satisfaction was markedly higher with YE (4.8 ± 0.04) compared to WLI (3.4 ± 0.6), with a p-value of <0.001. The steps performed faster with YE scored 4.7 ± 0.05, significantly better than 3.0 ± 0.7 for WLI, indicating that YE contributed to improved procedural efficiency. Additionally, YE was perceived to prevent blood loss more effectively, scoring 4.8 ± 0.04 compared to 3.1 ± 0.6 for WLI, with a p-value of <0.001. The statistical significance of these findings was determined through independent t-test.

The present study provides a comparative evaluation of Yellow Enhancement (YE) Imaging versus White Light Imaging (WLI) in improving intraoperative visualization during laparoscopic cholecystectomy and inguinal hernia repair.

Advancements in laparoscopy have significantly improved intraoperative visualization and surgical outcomes in minimally invasive procedures. In our study, YE technology demonstrated its utility by enhancing tissue differentiation and vascular visualization through advanced color contrast technology. This improved clarity aids in precise dissection and reduces the risk of intraoperative complications.

Similarly, the Enhanced Laparoscopic Vision System (ELViS), as presented by Trilling B et al (2021), addresses another critical limitation of conventional laparoscopy that is blind spots, by providing a broader field of view through the integration of lateral cameras. This expanded visualization mitigates blind spots, enhancing spatial awareness and overall surgical precision. While YE focuses on optimizing tissue visualization through enhanced contrast, ELViS complements this progress by improving the surgeon’s field of vision.⁵ Together, such innovations represent significant strides in laparoscopy, facilitating safer, more efficient surgical interventions.

The findings of the present study strongly support the superiority of YE over WLI in terms of clarity, contrast, and overall surgical efficiency. Conventional WLI, while widely used as the standard modality for laparoscopic surgeries, often fails to provide sufficient differentiation between tissues, such as fat, vascular structures, and avascular planes (Images-1,3,5,7). This limitation can lead to prolonged surgical time, increased risk of injury to critical structures, and reduced surgical precision. The emergence of YE addresses these shortcomings by enhancing tissue contrast, thereby allowing for better visualization of anatomical landmarks (Images-2,4,6,8) which was also discussed by Suherman RC et al, (2024).⁴

The observations in present study are consistent with findings reported by Ballal M (2024)⁶ and Okabayashi K⁷ which further emphasize YE’s role in improving tissue contrast and surgical precision. In our study, YE significantly improved the clarity of vascular structures (mean score: 4.8 ± 0.03) and fat differentiation (4.7 ± 0.04), both of which are critical for safe and precise dissection. Similarly, in a study by Okabayashi K⁷, YE was noted to emphasize yellow tones through color conversion, making tissues with strong yellow components more visible. This was particularly advantageous in colorectal cancer surgeries where YE improved the visibility of adipose tissue boundaries through the adherent fascia. Okabayashi K⁷ further demonstrated the utility of YE in mesorectal dissections, where it delineated the boundary between the rectal wall and mesorectal fat. This ability to identify boundaries clearly, especially in obese patients, aligns with our findings where YE helped delineate hernial defects and fat-rich omental structures during inguinal hernia repair (Images-1 and 2).

Image:1 Intraoperative laparoscopic view under WLI during inguinal hernia repair, showing two midline hernial openings with reduced contrast, a less distinct omentum blending into the surrounding tissues, and moderately visible surrounding muscles and intestines.

Image-2: Intraoperative laparoscopic view under YE mode during an inguinal hernia repair, providing high contrast to highlight two midline hernial openings, the fat-rich yellowish omentum protruding through the defects, and moderately visible surrounding muscles and intestines. The YE mode emphasizes fatty tissues, aiding in clear delineation of hernial edges and omental structures.

Similarly, Ballal M (2024)⁶ highlighted YE’s ability to enhance posterior fat pads, hiatal pillars, and pancreatic structures. Ballal M (2024)⁶ noted that YE aided in distinguishing anterior and posterior dissection planes, improving the ease of identifying critical structures like the phreno-esophageal ligament. This observation mirrors our findings, where YE facilitated the identification of avascular planes (mean score: 4.9 ± 0.02) and provided clear contrast between fatty tissues and adjacent structures (Images-3,4,7,8). For instance, during cholecystectomy, YE markedly improved the visualization of Calot’s Triangle (Images-5 and 6), a critical area for avoiding bile duct injuries.

Image-3: Intraoperative laparoscopic image using WLI during cholecystectomy, showing the bile duct, liver, and poorly differentiated omental and peritoneal fat appearing in shades of white and gray, alongside prominent blood vessels with limited clarity and contrast.

Image-4: Intraoperative laparoscopic image using YE imaging during cholecystectomy, highlighting the bile duct, liver, yellow-enhanced omental and peritoneal fat and brightly enhanced red blood vessels, offering high contrast and improved differentiation of fatty tissues and vascular structures.

Image-5: Intraoperative laparoscopic image during cholecystectomy using WLI, showing the gallbladder, bile duct, and liver with fatty tissues appearing in shades of white and gray with poorly differentiated fat blending with surrounding tissue and prominent blood vessels lacking enhanced clarity.

Image-6: Intraoperative laparoscopic high contrast image during cholecystectomy using YE Imaging, highlighting Calot's Triangle, bright yellow-enhanced fatty tissues, greenish dissected fat, enhanced red blood vessels, and the gallbladder attached to the liver offering improved differentiation of fatty tissues and vascular structures.

Image-7: Intraoperative laparoscopic view under WLI during a laparoscopic cholecystectomy, showing the omentum with less distinct contrast, the partially visible fundus of the gallbladder blending into surrounding tissues, and peripheral structures like costal cartilage and the transversus abdominis muscle appearing less defined.

Image-8: Intraoperative laparoscopic view under YE mode during a laparoscopic cholecystectomy, providing high contrast to highlight the fat-rich yellowish omentum, the partially obscured fundus of the gallbladder, along with peripheral structures like costal cartilage and the transversus abdominis muscle.

In the present study surgeons expressed higher satisfaction with YE (4.8 ± 0.04) compared to WLI (3.4 ± 0.6) and reported that procedural steps were performed faster with YE (4.7 ± 0.05). This improvement can be attributed to YE’s ability to enhance contrast between tissues. Similarly, the enhanced clarity of vascular structures under YE contributed to better blood loss prevention (4.8 ± 0.04), which is consistent with observations by Ballal M⁶ and Okabayashi K⁷ regarding YE’s role in improving procedural safety.

In specific surgical scenarios, our study demonstrated YE’s utility in laparoscopic cholecystectomy and inguinal hernia repair, two of the most commonly performed minimally invasive procedures. During hernia repair, YE distinctly highlighted hernial openings and surrounding omental tissues, which ensured better identification of defect margins and facilitated accurate mesh placement (Images-1 and 2). This correlates with findings of Okabayashi K⁷ where YE confirmed fatty tissue remnants post-dissection, ensuring procedural completeness. Similarly, Ballal M(2024)⁶ emphasised on YE’s role in identifying fatty and vascular structures near the pancreas and hiatal regions underscoring its broader applicability to complex surgical areas.

Another key advantage noted across studies is YE’s ability to improve the visualization of nerve tissues. While Okabayashi K⁷ highlighted YE’s utility in identifying nerve structures buried in adipose tissue, our study also demonstrated enhanced visualization of avascular and fat-rich planes, which indirectly aids in nerve preservation during dissection. This benefit further expands YE’s potential application to procedures where nerve preservation is critical, such as colorectal and urological surgeries.

From a safety and efficiency perspective, the present study demonstrated that YE reduces the risk of intraoperative complications by enhancing tissue clarity and differentiation. This aligns with the safety benefits reported in studies by Okabayashi K⁷ and Ballal M(2024)⁶, where YE improved identification of tissue boundaries, minimizing surgical errors and ensuring procedural precision. The statistically significant differences in visualization parameters (p-values < 0.001) in our study further strengthen these findings.

The clinical importance of YE, as highlighted in this study and corroborated by previous research, underscores its value as a significant advancement in intraoperative imaging technology, warranting broader adoption across MIS practices.A

This study demonstrates that YE Imaging is significantly superior to WLI in improving intraoperative visualization during laparoscopic cholecystectomy, inguinal hernia repair, and all other laparoscopic surgeries, particularly adhesiolysis. YE enhances tissue contrast, improves clarity of vascular structures and avascular planes, and facilitates better differentiation as well as removal of fatty tissues, such as omentum and adipose tissue. Additionally, YE contributes to increased surgeon satisfaction, reduced blood loss, and enhanced procedural efficiency. These findings suggest that YE can address limitations of conventional WLI, reducing surgical complications and improving overall outcomes.

RECOMMENDATIONS

Hospitals and surgical centers should consider adopting Yellow Enhancement (YE) technology into their laparoscopic surgical workflows, especially for procedures requiring precise anatomical visualization. To facilitate this, training programs should be developed to familiarize surgeons with YE imaging, emphasizing its advantages and best practices for optimizing visualization during surgeries. Further research is recommended, including studies with larger sample sizes, multi-center trials, and diverse surgical procedures to validate the broader clinical benefits of YE imaging. Additionally, future studies should focus on performing cost-benefit analyses to evaluate the economic implications of implementing YE technology, particularly its impact on surgical efficiency, reduced complications, and improved patient recovery times.

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