An early detection of insufficiently perfused skin flaps can reduce complications and improve treatment results after reconstructive surgeries.

Until 72 hours after surgery, insufficiently perfused flap transplants are not necessarily detectibly by mere visual monitoring. At the point when poor circulation is detectable with the naked eye, the flap is in a much worse condition. It not only harder to salvage but also has a higher revision expense.

Pseudo-color images of a flap on the right hand

Pseudo-color images of a flap on the right hand

With the TIVITA™ Tissue system, oxygenation and perfusion anomalies in flaps can be detected much earlier. That way, attending physicians can intervene much sooner and reduce complications. The TIVITA™ Tissue system is able to visualize the total hemoglobin and the oxygenation of the tissue in pseudo-color images.

Hence, it serves as an important tool for identifying arterial insufficiencies, venous congestion and differentiate between the two of them: Surgeons can see the difference in tissue oxygenation during surgery and take countermeasures when an insufficient perfusion is detected.
Ultimately, an early detection of deficient tissue oxygenation in flaps leads to a less suffering in patients, a lower number of surgical interventions and reduced costs for the health care system.

Flap transplant under the right eye, directly after surgery

Flap transplant under the right eye, directly after surgery

Flap transplant under the right eye, directly after surgery

4 days post operative

Flap transplant under the right eye, 4 days after surgery

Flap transplant under the right eye, four days after surgery

Flap transplant at the right leg, postoperative

Flap transplant at the right leg, postoperative

Flap transplant at the right leg, postoperative


 
 
“Two criteria tested provide objective evaluation of flap viability and facilitate diagnosis of flap ischemia bevor clinically apparent. Earlier diagnosis should lead to earlier intervention and higher salvage rates. Salvaged flaps should have less fat necrosis because ischemic time can be shortened. The new criteria allow clinicians to assess flaps remotely, eliminate subjectivity and help explain variations in StO2 that are normal or caused by events such as micro emboli.”
 
“Two indicators of hypoxia, StO2 ≤ 30% and its drop rate, were used simultaneously. All flaps with StO2 ≤ 30% and a drop rate ≥ 20% per hour, both sustained more than 30 minutes, were flaps with complications The sensitivity, specificity, positive predictive value, and negative predictive value were each 100% and statistically significant.”

[Keller, Alex. “A new diagnostic algorithm for early prediction of vascular compromise in 208 microsurgical flaps using tissue oxygen saturation measurements.” Annals of plastic surgery 62.5 (2009): 538-543.]

“Near-infrared spectroscopy seems to be a highly suitable candidate for postoperative flap monitoring. Larger-scale, randomized, multicentric clinical trials are needed in the future.”
[Chen, Ying, et al. “Free flap monitoring using near-infrared spectroscopy: a systemic review.” Annals of plastic surgery 76.5 (2016): 590-597.]

“Hyperspectral imaging (HSI) can help surgeons make quick decisions in the operating room, as it detects issues not visible to the naked eye.”
[Javier La Fontaine, Ph.D.: University of Texas Southwestern Medical Center]
 
We measure in the visible (VIS) and invisible, near-infrared (NIR) range, whereby we can represent non-visible abnormalities for humans. This is non-invasive, imaging and within a few seconds.
 
For more information on how to interpret our images, please click »here
 

Literatur
[1] Sowa, M. G., Kuo, W. C., Ko, A. C., & Armstrong, D. G. (2016). Review of near-infrared methods for wound assessment. Journal of biomedical optics, 21 (9), 091304-091304.

[2] Perng, C. K. (2013). Recent advances in postoperative free microvascular flap monitoring. Formosan Journal of Surgery, 46 (5), 145-148.

[3] Marotz, J., Siafliakis, A., Holmer, A., Kulcke, A., & Siemers, F. (2015). First results of a new hyperspectral camera system for chemical based wound analysis. Wound Medicine, 10, 17-22.

[4] Myers, D., McGraw, M., George, M., Mulier, K., & Beilman, G. (2009). Tissue hemoglobin index: a non-invasive optical measure of total tissue hemoglobin. Critical Care, 13 (5), 1.

[5] Lu, G., & Fei, B. (2014). Medical hyperspectral imaging: a review. Journal of biomedical optics, 19 (1), 010901-010901.

[6] Bashkatov, A. N., Genina, E. A., Kochubey, V. I., & Tuchin, V. V. (2005). Optical properties of human skin, subcutaneous and mucous tissues in the wavelength range from 400 to 2000 nm. Journal of Physics D: Applied Physics, 38 (15), 2543.

[7] Keller, Alex. “A new diagnostic algorithm for early prediction of vascular compromise in 208 microsurgical flaps using tissue oxygen saturation measurements.” Annals of plastic surgery 62.5 (2009): 538-543.

[8] Yafi, Amr, et al. “Postoperative quantitative assessment of reconstructive tissue status in cutaneous flap model using spatial frequency domain imaging.” Plastic and reconstructive surgery 127.1 (2011): 117.