An Adolescent With a Retropharyngeal Swelling: To Drain or Not to Drain?: Keeping a Broad Vision During the COVID-19 Pandemic

CASE PRESENTATION: An 18-year-old patient with a history of COVID-19 (1 month previously) was admitted with malaise and complaints of a stiff neck, a left-sided cervical mass, headache, and difficulty in swallowing and breathing, which had been present for 4 days. Two days after the onset of the first symptoms, a painless skin rash on the legs, arms, palms of both hands, and soles of both feet developed. Despite 2 days of treatment with antibiotics (amoxicillin/clavulanic acid, 500/125 mg three times daily orally), symptoms progressed. On presentation, the patient was alert and oriented, there were no neurologic disorders, and all symptoms related to the recent COVID-19 infection had subsided. His medical history was negative for sexually transmitted diseases, and the patient had received all vaccines except for meningococcus and COVID-19

Molecular guided surgery advances

Purpose Despite major advancements in surgical oncology, the positive margin rate for primary head and neck cancer resection remains around 15-30%. Inadequate margins are directly correlated to poor survival, and as such, mitigation of these rates is critical to improve patient outcomes. We have developed an ex vivo imaging strategy that utilizes fluorescence intensity-peaks (relative to background signal) to locate potential close or positive margins on the deep surface of the resected tumor specimen. Experimental Design A clinical trial with over 50 patients with head and neck cancer scheduled for surgery received systemic administration of a tumor-specific contrast agent (panitumumab-IRDye800). After surgical resection, the tumor specimen was imaged in vivo during surgical resection and using a 3D specimen mapping device with optical capability. The three highest fluorescence intensity-peaks on the deep surface of the specimen were isolated and correlated to histology to determine the margin distance at these regions. Results Relative fluorescence peak-intensities identified the closest margin on the deep surface of the specimen within 2.5 minutes. In vivo imaging identified multiple areas that would be considered management changing events. The highest intensity-peak consistently (100%) detected the closest margin to the tumor. Conclusion Fluorescence intensity-peaks can identify the region on the specimen where tumor is closest to specimen’s edge on the deep surface. This technique could have broad applications in obtaining adequate margins in oncological surgery

Sensorineural Hearing Impairment Recovery after Transmastoidal Surgery for a Petrous Apex Cholesterol Granuloma:A Case Report

Cholesterol granulomas are the most common primary lesions of the petrous apex. Although their benign character, impingement of critical neurovascular structures can cause significant symptomatology such as hearing impairment. We present unique results after treatment of a cholesterol granuloma located in the petrous apex causing sensorineural hearing impairment. A transmastoidal approach was performed using an intraoperative computed tomography-guided navigation system. The video, which is included for reference, illustrates clear drainage of the cyst and drain positioning. The hearing improved completely in the lower frequencies at 500 and 1000 Hz and with a 19 dB improvement in overall bone conduction in the affected ear

Integrating topology optimization in precision motion system design for optimal closed-loop control performance

In pursuit of better accuracy, higher speed and larger scale, manufacturers of high-performance devices increasingly rely on components which have been designed with a multidisciplinary approach from the outset. In the context of motion systems, this means that for instance structural mechanics, control engineering and thermal analysis are considered early in the design. In addition, the prospect of producing freeform device components using additive manufacturing at full scale allows designers to even further refine components to a specific purpose, or even integrate multiple functions into a single component. The design freedom offered by additive manufacturing is far greater than that offered by traditional techniques. To exploit this freedom a topology optimization framework is proposed that allows to determine the optimal material quantity and distribution within a design volume. In particular, this article focuses on the closed-loop control performance of a motion system component, while simultaneously ensuring that mechanical requirements are met. Based on an example, it is demonstrated that this leads to nontrivial and non-intuitive designs which provide improved performance at lower structural mass compared to eigenfrequency designs. The framework allows rapid development of prototype designs, which may eliminate some of the costly design iterations which are currently made in industrial practice.Accepted Author ManuscriptStructural Optimization and Mechanic

Intraoperative Molecular Imaging for ex vivo Assessment of Peripheral Margins in Oral Squamous Cell Carcinoma.

Objective: Complete surgical resection is the standard of care for treatment of oral cancer although the positive margin rate remains 15-30%. Tissue sampling from the resected specimen and from the wound bed for frozen section analysis (FSA) remains the mainstay for intraoperative margin assessment but is subject to sampling error and can require the processing of multiple samples. We sought to understand if an ex vivo imaging strategy using a tumor-targeted fluorescently labeled antibody could accurately identify the closest peripheral margin on the mucosal surface of resected tumor specimen, so that this sentinel margin could be used to guide pathological sampling. Materials and Methods: Twenty-nine patients with oral squamous cell carcinoma scheduled for surgical resection were consented for the study and received systemic administration of a tumor-targeted fluorescently labeled antibody (Panitumumab IRDye800CW). After surgical resection, the tumor specimen was imaged using a closed-field fluorescent imaging device. Relevant pathological data was available for five patients on retrospective review. For each of these five patients, two regions of highest fluorescence intensity at the peripheral margin and one region of lowest fluorescence intensity were identified, and results were correlated with histology to determine if the region of highest fluorescence intensity along the mucosal margin (i.e., the sentinel margin) was truly the closest margin. Results: Imaging acquisition of the mucosal surface of the specimen immediately after surgery took 30 s. In all of the specimens, the region of highest fluorescence at the specimen edge had a significantly smaller margin distance than other sampled regions. The average margin distance at the closest, sentinel, margin was 3.2 mm compared to a margin distance of 8.0 mm at other regions (p < 0.0001). Conclusions: This proof-of-concept study suggests that, when combined with routine FSA, ex vivo fluorescent specimen imaging can be used to identify the closest surgical margin on the specimen. This approach may reduce sampling error of intraoperative evaluation, which should ultimately improve the ability of the surgeon to identify the sentinel margin. This rapid sentinel margin identification improves the surgeons orientation to areas most likely to be positive in the surgical wound bed and may expedite pathology workflow