Dynamic infrared thermography (DIRT) for assessment of skin blood perfusion in cranioplasty: a proof of concept for qualitative comparison with the standard indocyanine green video angiography (ICGA).

PURPOSE: Complications in wound healing after neurosurgical operations occur often due to scarred dehiscence with skin blood perfusion disturbance. The standard imaging method for intraoperative skin perfusion assessment is the invasive indocyanine green video angiography (ICGA). The noninvasive dynamic infrared thermography (DIRT) is a promising alternative modality that was evaluated by comparison with ICGA. METHODS: The study was carried out in two parts: (1) investigation of technical conditions for intraoperative use of DIRT for its comparison with ICGA, and (2) visual and quantitative comparison of both modalities in a proof of concept on nine patients. Time-temperature curves in DIRT and time-intensity curves in ICGA for defined regions of interest were analyzed. New perfusion parameters were defined in DIRT and compared with the usual perfusion parameters in ICGA. RESULTS: The visual observation of the image data in DIRT and ICGA showed that operation material, anatomical structures and skin perfusion are represented similarly in both modalities. Although the analysis of the curves and perfusion parameter values showed differences between patients, no complications were observed clinically. These differences were represented in DIRT and ICGA equivalently. CONCLUSIONS: DIRT has shown a great potential for intraoperative use, with several advantages over ICGA. The technique is passive, contactless and noninvasive. The practicability of the intraoperative recording of the same operation field section with ICGA and DIRT has been demonstrated. The promising results of this proof of concept provide a basis for a trial with a larger number of patients.

[Iliac crest bone graft with vascular pedicle after Caldwell-Luc procedure]. / Mikrochirurgischer Beckenkammtransfer nach erfolgter Caldwell-Luc-Operation.

The standard Caldwell-Luc procedure includes the removal of most of the maxillary sinus mucosa and the introduction of an inferior meatal antrostomy to promote sinus drainage. Pain, chronic relapsing inflammation and loss of volume are typical sequels of this procedure. Partial maxillary resection and iliac crest bone graft harvesting is a new concept and treatment option in such cases. The case of a 64-year-old woman who had previously undergone several unilateral sinus operations is presented. Fluorescein imaging was used to detect bone areas of low blood perfusion in the sinus walls. All affected bone and granulation tissue were removed. After resection, an iliac crest bone graft with vascular pedicle was performed to reconstruct the maxillary defect. Postoperative CT and scintigraphic imaging revealed a vital transplant. At the 10-month follow-up, no inflammation was observed and chronic pain was significantly reduced. The results clearly demonstrate that maxillary resection and iliac crest bone graft harvesting might be an option to treat severe cases of chronic sinusitis. Further prospective studies are necessary to confirm the advantages of this technique.

[Intraoral application of vacuum-assisted closure in the treatment of an extended mandibular keratocyst]. / Intraorale Vakuumtherapie zur Behandlung einer ausgedehnten Zyste des Unterkieferknochens.

In extended cysts of the jaw bone particular demands are made in terms of wound closure, especially if an intraoral surgical approach is chosen. A tight closure is even more important if the bony defect has been filled with an alloplastic material or autologous cancellous bone. In our case a keratocyst of the left mandibular angle and ascending ramus was treated. After enucleation of the cyst and grafting with autologous cancellous bone the graft was lost following a wound breakdown. Subsequently a system was developed to apply intraoral V.A.C.-therapy. This led to a safe separation of the cystic defect and the oral cavity and a conditioning of the wound ground. A grafting with an alloplastic material was carried out successfully. With this method the length of treatment could be reduced by several months compared to a conventional therapy with an obturator.