Sialendoscopy and CT navigation assistance in the surgery of sialolithiasis

Background A sialendoscopy-assisted combined approach is well established in the surgery of sialolithiasis. In cases of proximal salivary stones, transcutaneous sialendoscopy-assisted extractions with parotid and submandibular gland preservation is the primary intention of treatment. We recently added computer tomography (CT) navigation to improve the results of this challenging surgery equally in both localizations. Patients and methods Al l the patients who submitted to sialendoscopy and sialendoscopy-assisted procedures at the tertiary institution between January 2012 and October 2020 were included in the present study. From November 2019, CT navigation was added in cases with sialolithiasis and a presumably poor sialendoscopic visibility. We evaluated the parameters of the disease, diagnostic procedures, sialendoscopic findings and outcomes, with or without optical surgical navigation. Results We performed 178 successful salivary stone removals in 372 patients, of which 118 were combined sialendos-copy-assisted approaches, including 16 transcutaneous proximal, 10 submandibular and 6 parotid stone operations. Surgical navigation was used in six patients, four times for submandibular and twice for parotid sialolithiasis. These were all non-palpable, sialendoscopically invisible or partially visible stones, and we managed to preserve five of the six salivary glands. Conclusions The addition of CT navigation to sialendoscopy-assisted procedures for non-palpable, sialendoscopically invisible and fixed stones is a significant advantage in managing sialolithiasis. By consistently performing sialendoscopy and related preservation procedures, we significantly reduced the need for sialoadenectomies in patients with obstructive salivary gland disease.

Novel Peptide NIRF Optical Surgical Navigation Agents for HNSCC

Head and neck squamous cell carcinoma (HNSCC) survival rates have not improved in a decade, with a 63% 5-year recurrence rate after surgery, making HNSCC a compelling indication for optical surgical navigation (OSN). A promising peptide, HN1, targeted and internalized in human HNSCC cells in multiple laboratories, but was slow (24 h) to accumulate. We modified HN1 and explored structural variables to improve the uptake kinetics and create IRdye800 adducts useful for OSN. Eleven new molecules were synthesized and characterized chemically, in human HNSCC cells (Cal 27), and in HNSCC xenograft mice. Cal 27 flank xenografts in Balb/c nude mice were imaged for 3–48 h after 40 nmol intravenous doses of IR800-labeled molecules. Cell uptake kinetics in the 1–2 h window incubated at 1–10 μM were independent of the dye label (FITC, Cy5, or IR800), but increased markedly with additional N-terminal lipophilic substitution, and after resequencing the peptide to separate polar amino acids and move the lysine-dye more centrally. Microscopy confirmed the strong Cal 27 cell binding and demonstrated primarily cytosolic and membrane localization of the fastest peptide, 4Iphf-HN17. 4Iph-HN17-IR800 showed 26-fold greater rate of uptake in cells than HN1-IR800, and far stronger OSN imaging intensity and tumor to background contrast in mice, suggesting that the new peptide is a promising candidate for OSN of HNSCC.

Design of smart tools to support pre- and intra-operative use of surgical navigation systems

In this paper we present novel solutions to support the application of computer assisted surgical interventions in which optical surgical navigation systems based on stereo cameras are used. The objective is to improve both the pre-operative setup and the intra-operative use of the navigation system. Following a short introduction describing the potential for improvements of existing navigation systems new approaches and the components to implement them are described. The pre-operative alignment of the stereo camera is made easier by attaching a small graphic display to its tripod which can show how much of the operating area is covered by the measurement volume of the camera. The intra-operative application is improved by a mechanism for motorized camera motions in order to follow the position of surgical instruments. Furthermore a small display can be attached to a surgical instrument which clearly indicates to the surgeon how to guide the instrument in order to stay on the planned trajectory.