Video-assisted thoracoscopic wedge resection of multiple small, non-visible, and nonpalpable pulmonary nodules is a clinical challenge. We propose an ultra-minimally invasive technique for ...localization of pulmonary nodules using the electromagnetic navigation bronchoscope (ENB)-guided transbronchial indocyanine green (ICG) injection and intraoperative fluorescence detection with a near-infrared (NIR) fluorescence thoracoscope.
Fluorescence properties of ICG topically injected into the lung parenchyma were determined using a resected porcine lung. The combination of ENB-guided ICG injection and NIR fluorescence detection was tested using a live porcine model. An electromagnetic sensor integrated flexible bronchoscope was geometrically registered to the three-dimensional chest computed tomographic image data by way of a real-time electromagnetic tracking system. The ICG mixed with iopamidol was injected into the pulmonary nodules by ENB guidance; ICG fluorescence was visualized by a near-infrared (NIR) thoracoscope.
The ICG existing under 24-mm depth of inflated lung was detectable by the NIR fluorescence thoracoscope. The size of the fluorescence spot made by 0.1 mL of ICG was 10.4 ± 2.2 mm. An ICG or iopamidol spot remained at the injected point of the lung for more than 6 hours in vivo. The ICG fluorescence spot injected into the pulmonary nodule with ENB guidance was identified at the pulmonary nodule with the NIR thoracoscope.
The ENB-guided transbronchial ICG injection and intraoperative NIR thoracoscopic detection is a feasible method to localize multiple pulmonary nodules.
Abstract Objective(s) Localization and resection of non-visible, non-palpable pulmonary nodules during video-assisted thoracoscopic surgery (VATS) is challenging. Our study was to determine the ...feasibility and safety of indocyanine green (ICG) fluorescence localization and resection of small nodules using a near-infrared (NIR) fluorescence thoracoscope. Methods Twenty patients with undiagnosed peripheral nodules smaller than 3cm scheduled for CT-guided microcoil placement followed by VATS wedge resection were enrolled. After microcoil deployment, 100-150 μl of diluted ICG was injected percutaneously near the nodule. The nodule was initially localized solely by using the NIR thoracoscope to visualize ICG fluorescence. Thoracoscopic instruments were used to determine the staple line. Wedge resection was performed after confirmation of the location of the microcoil using fluoroscopy. Results Twenty patients underwent NIR image-guided VATS resection. The median CT tumor size was 1.2 cm. The median depth from the pleural surface was 1.4 cm (range: 0.2-4.8). The median CT-guided intervention time was 35 min and VATS procedural time was 54 min. ICG fluorescence was clearly identified in 18 of 20 cases (90%). The surgical margins were all negative on final pathology without the need of additional resection. The final diagnoses included 18 primary lung cancer, 1 metastatic lung cancer, and 1 benign lung tumor. Conclusions CT-guided percutaneous ICG injection and intraoperative NIR localization of small nodules is safe and feasible. It offers surgeons the ease of localization through direct ICG fluorescence imaging without the use of fluoroscopy and may be a complementary technique to preoperative microcoil placement for non-visible, non-palpable intrapulmonary nodules.
Computer-assisted surgery (CAS) can improve surgical precision in orthopaedic oncology. Accurate alignment of the patient's imaging coordinates with the anatomy, known as registration, is one of the ...most challenging aspects of CAS and can be associated with substantial error. Using intraoperative, on-the-table, cone-beam computed tomography (CBCT), we performed a pilot clinical study to validate a method for automatic intraoperative registration.
Patients who were ≥18 years of age, had benign bone tumors, and underwent resection were prospectively enrolled. In addition to inserting a navigation tracking tool into the exposed bone adjacent to the surgical field, 2 custom plastic ULTEM tracking tools (UTTs) were attached to each patient's skin adjacent to the tumor using an adhesive. These were automatically localized within the 3-dimensional CBCT volume to be used as image landmarks for registration, and the corresponding tracker landmarks were captured using an infrared camera. The main outcomes were the fiducial registration error (FRE) and the target registration error (TRE). The navigation time was recorded.
Thirteen patients with benign tumors in the femur (n = 10), tibia (n = 2), and humerus (n = 1) underwent navigation-assisted resections. The mean values were 0.67 ± 0.15 mm (range, 0.47 to 0.97 mm) for FRE and 0.83 ± 0.51 mm (range, 0.42 to 2.28 mm) for TRE. Registration was successful in all cases. The mean time for CBCT imaging and tracker registration was 7.5 minutes.
We present a novel automatic registration method for CAS exploiting intraoperative CBCT capabilities, which provided improved accuracy and reduced operative times compared with more traditional methods.
This proof-of-principle study validated a novel process for automatic registration to improve the accuracy of resecting bone tumors using a surgical navigation system.