Metal Allergy in Tracheostomy Tube Placement Resulting in Complete Subglottic Stenosis: A Case Report

Objectives: Metal hypersensitivity reaction to surgical implants is a well- known phenomenon that is associated with pain, swelling, inflammation, and decreased efficacy of the implant. We present a unique case of a patient with placement a metal Jackson tracheostomy tube that led to expeditious total subglottic stenosis. Methods: The patient was a 33-year old, severely atopic woman with history of asthma exacerbations requiring several intubations for acute respiratory failure with several subsequent tracheal dilations with steroid injections, and eventual tracheostomy placement with a metal Jackson tracheostomy tube that led to expeditious total subglottic stenosis. Results: Initial intervention included performing an airway evaluation, CO2 laser, and steroid injection of the area of complete subglottic stenosis. Follow up several months later revealed little improvement in level of tracheal narrowing proximal to the tracheostomy tube. Patient did not have shortness of breath but continued to be aphonic. Cricotracheal versus tracheal resection have been proposed but surgical morbidity was deemed too high due to patient’s obesity. Conclusions: Metal hypersensitivity reactions are well known phenomena as it relates to surgical implants in other surgical specialties but are seldom reported within the ear, nose and throat literature. Oftentimes, it takes astute observation to diagnose and establish a connection. Prompt recognition and treatment can be acquired from interdisciplinary collaboration with allergy.

Recent progress in Tannic Acid-driven antimicrobial/antifouling surface coating strategies

Medical devices and surgical implants are a necessary part of tissue engineering and regenerative medicines. However, the biofouling and microbial colonization on the implant surface continues to be a major...

USING OF CoCr ALLOYS IN BIOMEDICAL APPLICATIONS ( REVIEW)

Metals are used extensively in biomedical applications due to their mechanical strength, corrosion resistance, and biocompatibility. There are many types of metals and alloys used in this application ( stainless steel, Ti and Ti alloys, CoCr, dental amalgam, etc). This review focus on CoCr alloys which have excellent corrosion resistance and mechanical properties which make them the best choice for many types of surgical implants. There are many alloying elements used to improve the properties of CoCr alloy such as ( Zr, In, Ta, etc ) has been reviewed.

How relevant is lumbar bone mineral density for the stability of symphyseal implants? A biomechanical cadaver study

Purpose Osteoporotic bone tissue appears to be an important risk factor for implant loosening, compromising the stability of surgical implants. However, it is unclear whether lumbar measured bone mineral density (BMD) is of any predictive value for stability of surgical implants at the pubic symphysis. This study examines the fixation strength of cortical screws in human cadaver specimens with different BMDs. Methods The lumbar BMD of ten human specimens was measured using quantitative computed tomography (qCT). A cut-off BMD was set at 120 mg Ca-Ha/mL, dividing the specimens into two groups. One cortical screw was drilled into each superior pubic ramus. The screw was withdrawn in an axial direction with a steady speed and considered failed when a force decrease was detected. Required force (N) and pull-out distance (mm) were constantly tracked. Results The median peak force of group 1 was 231.88 N and 228.08 N in group 2. While BMD values differed significantly (p < 0.01), a comparison of peak forces between both groups showed no significant difference (p = 0.481). Conclusion Higher lumbar BMD did not result in significantly higher pull-out forces at the symphysis. The high proportion of cortical bone near the symphyseal joint allows an increased contact of pubic screws and could explain sufficient fixation. This condition is not reflected by a compromised lumbar BMD in a qCT scan. Therefore, site-specific BMD measurement could improve individual fracture management.

Expanding Poly(lactic acid) (PLA) and Polyhydroxyalkanoates (PHAs) Applications: A Review on Modifications and Effects

The high price of petroleum, overconsumption of plastic products, recent climate change regulations, the lack of landfill spaces in addition to the ever-growing population are considered the driving forces for introducing sustainable biodegradable solutions for greener environment. Due to the harmful impact of petroleum waste plastics on human health, environment and ecosystems, societies have been moving towards the adoption of biodegradable natural based polymers whose conversion and consumption are environmentally friendly. Therefore, biodegradable biobased polymers such as poly(lactic acid) (PLA) and polyhydroxyalkanoates (PHAs) have gained a significant amount of attention in recent years. Nonetheless, some of the vital limitations to the broader use of these biopolymers are that they are less flexible and have less impact resistance when compared to petroleum-based plastics (e.g., polypropylene (PP), high-density polyethylene (HDPE) and polystyrene (PS)). Recent advances have shown that with appropriate modification methods—plasticizers and fillers, polymer blends and nanocomposites, such limitations of both polymers can be overcome. This work is meant to widen the applicability of both polymers by reviewing the available materials on these methods and their impacts with a focus on the mechanical properties. This literature investigation leads to the conclusion that both PLA and PHAs show strong candidacy in expanding their utilizations to potentially substitute petroleum-based plastics in various applications, including but not limited to, food, active packaging, surgical implants, dental, drug delivery, biomedical as well as antistatic and flame retardants applications.

Feasibility evaluation of transtympanic laser stimulation of the cochlea from the outer ear

Infrared laser stimulation has been studied as an alternative approach to auditory prostheses. This study evaluated the feasibility of infrared laser stimulation of the cochlea from the outer ear bypassing the middle ear function. An optic fiber was inserted into the ear canal and a laser was used to irradiate the cochlea through the tympanic membrane in Mongolian gerbil. A pulsed infrared laser (10.1 mJ/cm2) and clicking sound (70 peak-to-peak equivalent sound pressure level) were presented to the animals. The amplitude of the laser-evoked cochlear response was systematically decreased following insertion of a filter between the tympanic membrane and cochlea; however, the auditory-evoked cochlear response did not decrease. The filter was removed and the laser-evoked response returned to around the original level. The amplitude ratio and the relative change in response amplitude before and during filter insertion significantly decreased as the absorbance of the infrared filter increased. These results indicate that laser irradiation could bypass the function of the middle ear and directly activate the cochlea. Therefore, an auditory prosthesis based on laser stimulation represents a possible noninvasive alternative to conventional auditory prostheses requiring surgical implants.