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Longitudinal and perpendicular changes in the vocal fold's blood vessels are associated with the development of benign and malignant laryngeal lesions. The combination of Contact Endoscopy (CE) and Narrow Band Imaging (NBI) can provide intraoperative real-time visualization of the vascular changes in the laryngeal mucosa. However, the visual evaluation of vascular patterns in CE-NBI images is challenging and highly depends on the clinicians' experience. The current study aims to evaluate and compare the performance of a manual and an automatic approach for laryngeal lesion's classification based on vascular patterns in CE-NBI images. In the manual approach, six observers visually evaluated a series of CE+NBI images that belong to a patient and then classified the patient as benign or malignant. For the automatic classification, an algorithm based on characterizing the level of the vessel's disorder in combination with four supervised classifiers was used to classify CE-NBI images. The results showed that the manual approach's subjective evaluation could be reduced by using a computer-based approach. Moreover, the automatic approach showed the potential to work as an assistant system in case of disagreements among clinicians and to reduce the manual approach's misclassification issue.

The structure and organization of blood vessels in the vocal fold go through changes during the advancement from healthy to benign and further on to malignant stages. Contact Endoscopy (CE) is an optical technique providing real-time information related to the vascular structure of laryngeal mucosa. However, this technique comes with subjectivity in the interpretation of vascular patterns. In this study, a novel automated approach is proposed for vessel pattern charac-terization and classification of larynx CE + Narrow Band Imaging (NBI) images. This method is mainly based on the computation of indicators related to the level of disorder of vessels. 12 features were extracted from the indicators and were fed into two supervised classifiers. Linear Support Vector Machine (SVM) and K-Nearest Neighbor (KNN) showed an accuracy of 95.76% and 93.92% for vascular patterns and 86.04% and 82.23% for larynx histopathologies classification, respectively. These promising results show that the proposed method can potentially solve the subjectivity issues of CE.

Purpose For the treatment of malignant diseases of the oral cavity and the larynx, a total or partial resection is the standard therapy, while in special cases chemo- and/or external radiation therapy is considered. Transoral access reduces trauma and hospitalization time. Transoral surgery is usually executed using external microscopic imaging. Therefore, the microscope is placed in the visual line of the opening of the mouth and throat. However, specific anatomical structures like the posterior commissure (dorsal end of the vocal cords) are not visible in these procedures. An endoscopic approach can improve this problem. We introduce a new prototype system for endoscopic assisted transoral surgery. Methods Based on clinical observation and discussions with professional users and surgeons, the clinical need was identified and specified. A general concept or an endoscopic manipulator to assist microlaryngeal surgery was designed. For that a steerable rigid endoscope was combined with an actuator that allows translational and rotational movement. A quick release fastener was designed allowing for fast change of the endoscope and independence from its shape and type. The actuator was fixed on a commercially available, semi-active medical holding arm for easy positioning. The holder can be fixed to the standard rails of the surgical table. The piezoelectric drives integrated in the actuator are activated with a foot pedal. This allows easy and fast fine positioning, while the hands are free to perform the surgery with standard instruments for microlaryngeal surgery. Results A prototype of the system for endoscopic assisted transoral surgery was developed. The entire technical setup was tested in terms of usability and performance in a simulated surgical scenario. A basic phantom, representing the throat and vocal cords was created and placed on a surgical table. The system was installed on the table and the clinical workflow of a simulated endoscopic assisted surgery on the vocal cords was performed. The performance of the setup and the procedure success was evaluated by clinical users. Conclusion Fixture of the system on the surgical table is fast and easy due to its low weight and compact design. The medical holder allows a fast initial positioning of the system in front of the phantom patient. An easy insertion and removal of the endoscope was realized using the quick release fastener. The developed endoscope fixation is universally adaptable and not limited to a single type of endoscope. The piezoelectric drives, combined with the foot pedal, allow a precise placement and readjustment of the endoscope during surgery. The use of a multi view endoscope enables a variable view on the surgical situs. The size and shape of the whole setup offer excellent access to the targeted structures. The development was classified beneficial by the clinical users.

Purpose: Recent advances in endoscopy have led to new technologies with significant optical imaging improvements. Since its development a few years ago, narrow-band imaging (NBI) has already been proved useful in detecting malignant lesions and carcinoma in clinical settings of urology, gastroenterology and ENT. The potential of this technology for imaging applications of the arterial vessel wall has not been properly analysed yet, but with the observed benefits could prove valuable for this clinical use as well., Methods: In order to assess the efficacy of NBI, defects such as burns and mechanical tears were created on the walls of an arterial vessel sample. Ex vivo imaging using NBI and white light imaging (WLI) were performed with rigid and flexible fibre endoscopes., Results: A thorough comparison of the images proved that NBI enhances the visualisation of lesions and defects on the artery walls compared to normal WLI., Conclusion: WLI provides a direct image of the vessel lumen and its anatomical shape. It is suitable for observation and documentation of intravascular therapies. NBI images are more distinct and have more contrast. This helps to detect even small defects or changes on the inner vessel wall that could provide additional information and lead to more precise and personalised therapies.

This work presents a novel approach for detecting underlying pulsatile structures with laparoscopic tools by using proximal vibroacoustic sensing. This new method could detect pulsations at a depth of up to 1.5 cm. The outcome of this work indicates the potential of identifying deep-seated pulsatile structures during robot-assisted laparoscopy, where haptic feedback is highly limited, to help surgeons prevent vascular damage that may lead to injuries. [ABSTRACT FROM AUTHOR]

Vascular endoscopic imaging is known for a long time but has never made its way into clinical routine. Reasons for that are the complexity, lack of low-cost portable systems, and the lack of suitable endoscopes providing high image quality with small dimensions. In addition, an interruption of the blood flow caused by the device and the opacity of blood are difficult to manage. In the past we have already developed ideas to overcome these difficulties and now we present a feasibility test of a thin diameter ureteroscope for observation of vascular procedures. The imaging system was tested in a phantom where side branches were explored, a stent was placed and a simulated aneurysm coiled.

For imaging of the vascular structure, angiography is state of the art. This can be done by contrast enhanced XRay, CT or MR imaging. But these modalities typically only show the blood flow and do not allow a depiction of the vasculature itself. To provide information about the vessel walls and plaques narrowing the blood flow, catheter based intra vascular ultrasound or vascular optical coherence tomography can be used. Optical endoscopic imaging is rarely used in vascular diagnosis. But endoscopic imaging can depict superficial inflammations or defects of the intima vessel layer and the real anatomical shape of the inner vasculature e.g. at bifurcations or aneurysms. Since OCT and endoscopic imaging both need a flushing to remove the blood for a short time, a combination of both modalities seems viable. For combining the two modalities, various background studies were performed including the selection of a feasible fibre endoscope, light source and camera system. A new pull-back and flushing device was designed and created for realizing the synchronous image acquisition using the two modalities. For calibration of the system and definition of the pullback and imaging parameters, first tests on artificial phantoms were performed. Then vascular and tissue models were imaged in a combined pullback mode after using the flush for complete blood removal. Endoscopic images were acquired in a video mode. The analysis of the images was done subjectively. As expected, the OCT provided structural information of the wall. The endoscopic images in combination with pullback appear blurry in video mode. The flushing liquid hinders the automatic focusing of the camera. Thus, smaller details could not be identified but bifurcations were visible. Even though the results were not good as expected, the study showed the potential of a bimodal system and addressed the issues faced in the initial implementation.

At present transoral laryngeal interventions are mainly observed and controlled by an external two dimensional direct microscopic view. This modality provides an overall view on the surgery situs in a straight line of sight. For treatment planning and appropriate documentation, an endoscopic inspection is mandatory prior to surgery. Nowadays a detailed endoscopic work-up of laryngeal lesions can be performed by contact endoscopy in combination with structure enhancement like Narrow Band Imaging. High resolution and magnification of up to 150 times provide detailed visualization of vascular structures and pathological changes of the tissue surface. In these procedures it is difficult however to localize the evaluated areas on large scale scenes like the microscopic view used for surgery. To provide a fast and easy image matching an automated vessel pattern recognition and allocation is presented. Endoscopic images depicting representative vessel structures of the vocal folds are selected out of contact endoscopy video scenes. These images are pre-processed for background homogenization. A Frangi Vessel Segmentation filter and morphological operations are used to extract the vessel structure and match it to the microscopic image. Using this method 4 detailed contact endoscopy images could be allocated in different scenes of the microscope video. This method can be used to simplify treatment planning and to prepare image data for documentation.

The endoscopic examination of subepithelial vascular patterns within the vocal fold is crucial for clinicians seeking to distinguish between benign lesions and laryngeal cancer. Among innovative techniques, Contact Endoscopy combined with Narrow Band Imaging (CE-NBI) offers real-time visualization of these vascular structures. Despite the advent of CE-NBI, concerns have arisen regarding the subjective interpretation of its images. As a result, several computer-based solutions have been developed to address this issue. This study introduces the CE-NBI data set, the first publicly accessible data set that features enhanced and magnified visualizations of subepithelial blood vessels within the vocal fold. This data set encompasses 11144 images from 210 adult patients with pathological vocal fold conditions, where CE-NBI images are annotated using three distinct label categories. The data set has proven invaluable for numerous clinical assessments geared toward diagnosing laryngeal cancer using Optical Biopsy. Furthermore, given its versatility for various image analysis tasks, we have devised and implemented diverse image classification scenarios using Machine Learning (ML) approaches to address critical clinical challenges in assessing laryngeal lesions. [ABSTRACT FROM AUTHOR]

One of the most applied imaging methods in medicine is endoscopy. A highly specialized image modality has been developed since the first modern endoscope, the "Lichtleiter" of Bozzini was introduced in the early 19th century. Multiple medical disciplines use endoscopy for diagnostics or to visualize and support therapeutic procedures. Therefore, the shapes, functionalities, handling concepts, and the integrated and surrounding technology of endoscopic systems were adapted to meet these dedicated medical application requirements. This survey gives an overview of modern endoscopic technology's state of the art. Therefore, the portfolio of several manufacturers with commercially available products on the market was screened and summarized. Additionally, some trends for upcoming developments were collected. [ABSTRACT FROM AUTHOR]