Clinical Scorecard: A New Approach for Localizing Pulmonary Nodules: Utilizing Indocyanine Green, Autologous Blood, and Methylene Blue in 272 Cases

At a Glance

Key Highlights

• ICG mixed with autologous blood and methylene blue provides dual protection to increase localization success and reliability.
• Localization agent concentration and volume optimization is critical to avoid pleural staining and ensure clear visualization under fluorescence.
• Preoperative localization reduces the risk of thoracotomy conversion and surgical failure in minimally invasive wedge resections for small pulmonary nodules.

Guideline-Based Recommendations

Diagnosis

• Use low-dose CT screening to detect pulmonary nodules early, especially post-COVID-19 pandemic.
• Confirm nodule size ≤ 2 cm and location suitable for wedge resection before localization.

Management

• Perform CT-guided percutaneous injection of a localization agent mixture (ICG, autologous blood, methylene blue) near the nodule within 24 hours before surgery.
• Use fluorescence endoscopy intraoperatively to visualize the nodule localization.
• Control localization agent volume (0.2–1.0 mL) and concentration (0.05 mg/mL ICG) to optimize visualization and minimize diffusion.

Monitoring & Follow-up

• Perform postoperative CT scan after localization to assess marker distribution and exclude complications such as pneumothorax or hemothorax.
• Evaluate localization efficacy intraoperatively using a standardized scoring system by experienced surgeons.

Risks

• Excessive localization agent volume may cause pleural staining and localization failure.
• Avoid localization in patients with pulmonary vascular lesions, lesions near major vessels, severe cardiopulmonary insufficiency, or bleeding tendency.

Patient & Prescribing Data

272 patients (110 males, 162 females) with pulmonary nodules meeting inclusion criteria for wedge resection

The mixture of ICG, autologous blood, and methylene blue was effective and safe for preoperative localization, improving surgical outcomes and minimizing complications.

Clinical Best Practices

• Use a 4K fluorescence endoscopy system for intraoperative visualization of ICG fluorescence.
• Inject localization agent at a 30°–45° angle under continuous CT fluoroscopic guidance to ensure accurate placement near the nodule.
• Withdraw needle slightly before injection to avoid bronchial or vascular entry.
• Limit the localization-surgery interval to less than 24 hours to maintain marker visibility.
• Employ a dual-dye approach (ICG and methylene blue) to provide backup localization in case of fluorescence failure.

References

• Global lung cancer statistics and mortality
• Surgical outcomes for early-stage lung cancer
• Randomized controlled trial comparing lobectomy and segmentectomy
• Survival rates between segmentectomy and wedge resection in stage Ia NSCLC
• Challenges in localizing small pulmonary nodules under thoracoscopy
• Use of indocyanine green for pulmonary nodule localization
• Enhanced permeability and retention effect of ICG
• ICG-human albumin mixture to reduce marker displacement