Aryepiglottic Cyst Developed Hours After Tracheal Intubation Causing Acute Upper Airway Ball-Valve Obstruction: A Case Report.

This is the first case report describing an aryepiglottic cyst resulting in critical airway compromise after an uneventful tracheal intubation. We present the case of a 55-year-old woman who developed acute dyspnea and stridor several hours after the surgery. She was found to have significant upper airway obstruction owing to a large left aryepiglottic cyst with a ball-valve effect.

Soft robotic manipulator for intraoperative MRI-guided transoral laser microsurgery.

Magnetic resonance (MR) imaging (MRI) provides compelling features for the guidance of interventional procedures, including high-contrast soft tissue imaging, detailed visualization of physiological changes, and thermometry. Laser-based tumor ablation stands to benefit greatly from MRI guidance because 3D resection margins alongside thermal distributions can be evaluated in real time to protect critical structures while ensuring adequate resection margins. However, few studies have investigated the use of projection-based lasers like those for transoral laser microsurgery, potentially because dexterous laser steering is required at the ablation site, raising substantial challenges in the confined MRI bore and its strong magnetic field. Here, we propose an MR-safe soft robotic system for MRI-guided transoral laser microsurgery. Owing to its miniature size (Ø12 × 100 mm), inherent compliance, and five degrees of freedom, the soft robot ensures zero electromagnetic interference with MRI and enables safe and dexterous operation within the confined oral and pharyngeal cavities. The laser manipulator is rapidly fabricated with hybrid soft and hard structures and is powered by microvolume (<0.004 milliter) fluid flow to enable laser steering with enhanced stiffness and lowered hysteresis. A learning-based controller accommodates the inherent nonlinear robot actuation, which was validated with laser path-following tests. Submillimeter laser steering accuracy was demonstrated with a mean error < 0.20 mm. MRI compatibility testing demonstrated zero observable image artifacts during robot operation. Ex vivo tissue ablation and a cadaveric head-and-neck trial were carried out under MRI, where we employed MR thermometry to monitor the tissue ablation margin and thermal diffusion intraoperatively.

Real-to-virtual domain transfer-based depth estimation for real-time 3D annotation in transnasal surgery: a study of annotation accuracy and stability.

PURPOSE: Surgical annotation promotes effective communication between medical personnel during surgical procedures. However, existing approaches to 2D annotations are mostly static with respect to a display. In this work, we propose a method to achieve 3D annotations that anchor rigidly and stably to target structures upon camera movement in a transnasal endoscopic surgery setting. METHODS: This is accomplished through intra-operative endoscope tracking and monocular depth estimation. A virtual endoscopic environment is utilized to train a supervised depth estimation network. An adversarial network transfers the style from the real endoscopic view to a synthetic-like view for input into the depth estimation network, wherein framewise depth can be obtained in real time. RESULTS: (1) Accuracy: Framewise depth was predicted from images captured from within a nasal airway phantom and compared with ground truth, achieving a SSIM value of 0.8310 ± 0.0655. (2) Stability: mean absolute error (MAE) between reference and predicted depth of a target point was 1.1330 ± 0.9957 mm. CONCLUSION: Both the accuracy and stability evaluations demonstrated the feasibility and practicality of our proposed method for achieving 3D annotations.

Real-time surgical tool tracking and pose estimation using a hybrid cylindrical marker.

PURPOSE: To provide an integrated visualisation of intraoperative ultrasound and endoscopic images to facilitate intraoperative guidance, real-time tracking of the ultrasound probe is required. State-of-the-art methods are suitable for planar targets while most of the laparoscopic ultrasound probes are cylindrical objects. A tracking framework for cylindrical objects with a large work space will improve the usability of the intraoperative ultrasound guidance. METHODS: A hybrid marker design that combines circular dots and chessboard vertices is proposed for facilitating tracking cylindrical tools. The circular dots placed over the curved surface are used for pose estimation. The chessboard vertices are employed to provide additional information for resolving the ambiguous pose problem due to the use of planar model points under a monocular camera. Furthermore, temporal information between consecutive images is considered to minimise tracking failures with real-time computational performance. RESULTS: Detailed validation confirms that our hybrid marker provides a large working space for different tool sizes (6-14 mm in diameter). The tracking framework allows translational movements between 40 and 185 mm along the depth direction and rotational motion around three local orthogonal axes up to [Formula: see text]. Comparative studies with the current state of the art confirm that our approach outperforms existing methods by providing nearly 100% detection rates and accurate pose estimation with mean errors of 2.8 mm and 0.72[Formula: see text]. The tracking algorithm runs at 20 frames per second for [Formula: see text] image resolution videos. CONCLUSION: Experiments show that the proposed hybrid marker can be applied to a wide range of surgical tools with superior detection rates and pose estimation accuracies. Both the qualitative and quantitative results demonstrate that our framework can be used not only for assisting intraoperative ultrasound guidance but also for tracking general surgical tools in MIS.

Saikosaponin-d Enhances the Anticancer Potency of TNF-α via Overcoming Its Undesirable Response of Activating NF-Kappa B Signalling in Cancer Cells.

Tumor necrosis factor-alpha (TNF- α ) was reported as anticancer therapy due to its cytotoxic effect against an array of tumor cells. However, its undesirable responses of TNF- α on activating NF- κ B signaling and pro-metastatic property limit its clinical application in treating cancers. Therefore, sensitizing agents capable of overcoming this undesirable effect must be valuable for facilitating the usage of TNF- α -mediated apoptosis therapy for cancer patients. Previously, saikosaponin-d (Ssd), a triterpene saponin derived from the medicinal plant, Bupleurum falcatum L. (Umbelliferae), showed to exhibit a variety of pharmacological activities such as antiinflammation, antibacteria, antivirus and anticancer. Recently, we found that Ssd could inhibit the activated T lymphocytes via suppression of NF- κ B, NF-AT and AP-1 signaling. Here, we showed that Ssd significantly potentiated TNF- α -mediated cell death in HeLa and HepG2 cancer cells via suppression of TNF- α -induced NF- κ B activation and its target genes expression involving cancer cell proliferation, invasion, angiogenesis and survival. Also, Ssd revealed a significant potency of abolishing TNF- α -induced cancer cell invasion and angiogenesis in HUVECs while inducing apoptosis via enhancing the loss of mitochondrial membrane potential in HeLa cells. Collectively, these findings indicate that Ssd has a significant potential to be developed as a combined adjuvant remedy with TNF- α for cancer patients.