Feasibility of bloodless liver resection using Lumagel, a reverse thermoplastic polymer, to produce temporary, targeted hepatic blood flow interruption

Indocyanine green fluorescence imaging techniques and interventional radiology during laparoscopic anatomical liver resection (with video)

BACKGROUND

To accomplish laparoscopic anatomical liver resection, intraoperative liver segmentation is necessary. Tattooing method or Glissonian approach will be used in a similar way to that in open liver resection. Moreover, in liver segment detection, the fluorescence of indocyanine green (ICG) means it has been recognized as a useful dye. In laparoscopy, however, there are technical difficulties in performing these conventional methods, so development of new techniques is necessary for liver segment identification. We report a pilot study using interventional radiology technique for laparoscopic intraoperative liver segmentation.

METHODS

Just prior to liver parenchymal resection, angiography was performed using a hybrid operation room. A catheter was inserted from the right femoral artery into the targeted arterial branch. After confirming the perfusion area by arteriography, embolic solution containing ICG was injected, and the branch was embolized. ICG fluorescence was observed by PINPOINT, a near-infrared imaging system.

RESULTS

Immediately after embolic solution injection, we were able to observe ICG fluorescence on the surface of the liver to be resected. This visual effect continued during liver parenchymal resection. We were able to confirm the intra-parenchymal boundary by observing ICG fluorescence on the cut surface of the resecting side and accomplished precise anatomical liver resection.

CONCLUSIONS

Our novel technique provides advances in laparoscopic anatomical liver resection performance. As two-dimensional laparoscopy lacks depth perception, additional visual information, such as ICG fluorescence imagery, is helpful as a navigation tool for precise laparoscopic anatomical liver resection.

An optimized procedure for stained bloodless anatomic hepatectomy in canines

BACKGROUND

Poloxamer 407 (P407) is a thermosensitive polymer that can gelatinize at body temperature and dissolve below critical temperature. The aim of this study was to evaluate an optimized procedure for hepatectomy, in which the target liver section was stained with methylene blue, and the blood inflow was occluded with P407.

METHODS

Twelve dogs were randomized into two equal groups. The conventional group (CG) underwent unstained liver resection with the hemi-Pringle maneuver for blood control. After angiography, the optimized group (OG) was cannulated to the target lobar hepatic artery via the femoral artery and to the target segmental portal vein via a branch of the splenic vein. The artery was then occluded with P407, whereas the vein was administered methylene blue and P407 sequentially before excision along the stained border. Blood specimens and necropsy were acquired periodically.

RESULTS

The stained resection margins were clearly visualized and were accompanied by negligible blood loss. The occlusion duration was significantly reduced from 24.5 ± 2.3 min in the conventional group to 18.5 ± 4.9 min in the OG (P < 0.05). The aspartate aminotransferase and alanine aminotransferase levels were less elevated in the OG postoperatively. No significant evidence of pathology was detected in either group.

CONCLUSIONS

This optimized procedure represents an easy, time-saving and effective approach for stained anatomic hepatectomy with temporary intravascular blood occlusion.

A New Segmental Hepatectomy Approach Using Ultrasound-Guided Portal Branch Infusion of a Thermosensitive Gel in Pigs

BACKGROUND

The aim of this study was to evaluate the safety, feasibility, and efficacy of a new segmental hepatectomy (SH) approach using intraoperative ultrasound (IOUS) guided infusion of a reversible thermosensitive gel into the portal vein branch in pigs;

MATERIALS AND METHODS

Poloxamer 407 aqueous solution (20%, W/V) was mixed with indocyanine green (P407-ICG) in this study to make it green, and it remained liquid at room temperature and turned into a firm gel upon reaching body temperature. In experiment I, six pigs were used to detect the outcome of infusing the mixture into the biliary tract, liver parenchyma, and hepatic vein for a safety study. In experiment II, another 12 pigs were randomly segmented into two groups [SH group and partial hepatectomy (PH) group] to investigate the feasibility and efficacy of the new approach using IOUS-guided infusion of the mixture into the portal branch;

RESULTS

No thermosensitive gel-induced abnormal changes were observed in the safety study. In the SH group, IOUS-guided infusion of the P407-ICG solution was effective in occluding the portal blood temporarily and demarcating the target liver segment to achieve precise SH. The blood loss in the SH group was significantly less than that of the PH group;

CONCLUSIONS

SH assisted by IOUS-guided infusion of the reversible thermosensitive gel into the feeding portal vein branches is feasible, safe, simple, and effective.