6 research outputs found
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Removal of a Wire Brush Bristle from the Hypopharynx Using Suspension, Microscope, and Fluoroscopy
Wire brush bristles are an increasingly recognized hazard that can present as a foreign body in the aerodigestive tract. Due to their small size and tendency to become embedded in surrounding tissue, these small metallic bristles present a unique operative challenge to otolaryngologists. Here we present a case of a 40-year-old woman who underwent endoscopic extraction of a wire bristle from the posterior pharyngeal wall using suspension, microscopy, and C-arm fluoroscopy. We believe this is the first published case of an endoscopic removal of a buried foreign body in the hypopharynx using these methods of localization concurrently. By leveraging multiple techniques for visualization, surgeons can avoid open exploration while ensuring complete removal of the object. Additionally, this case highlights the importance of regulatory oversight and consumer awareness of the hazards of grill brushes
Concurrent recording of the electrically-evoked compound action potential and the auditory brainstem response in cochlear implant users
Purpose and Technological Feasibility
• In the ABR waveform, WI reflects activity in the 8th cranial nerve while WV reflects activity in the upper brainstem. The amplitude ratio between WI and WV is emerging as an important metric for auditory function.
• In the electrically evoked ABR (eABR), eWI cannot be measured because of artifact associated with cochlear implant (CI) stimulation. The electrical eWI /eWV ratio therefore cannot be measured in a single test as the WI /WV ratio can for an acoustically evoked ABR.
• For MED-EL Corporation CIs, the electrically evoked compound action
potential (eCAP), equivalent to eWI, is measured with the Auditory nerve Response Telemetry (ART) test. The ART uses sequences of ‘masker’ and ‘probe’ biphasic pulses to extract an eCAP (see Fig. 1). Note that the ART also generates an external trigger
Traumatic incudomalleolar dislocation in a pediatric patient
Ossicular chain dislocation with associated conductive hearing loss often warrants surgical intervention such as ossiculoplasty. We present a case report of a 9-year-old male with a left longitudinal temporal bone fracture with associated asymmetric widening of the incudomalleolar joint and secondary hemotympanum. We document the patient's relevant clinical examination, testing, and imaging during clinic visits 2 weeks and 10 weeks after the inciting traumatic event. The patient was improved with no major medical or surgical intervention upon evaluation during the last follow-up visit. We discuss incudomalleolar joint dislocations and benefits of observation despite noting potential ossicular dislocation on imaging following the inciting event
Surgical management of a hemorrhagic pediatric brainstem cavernous malformation – A case report
Vascular malformations of the central nervous system such as cavernous malformations and arteriovenous malformations are rare lesions with controversial management recommendations in the pediatric population. We report a case of a 3-year-old male who presented with multiple discrete episodes of focal neurological deficits including ataxia and an abducens nerve palsy. Imaging revealed a 1.5 cm hemorrhagic mass located in the pons that was concerning for a cavernous malformation. This lesion was completely excised via a combined transpetrosal approach, and the patient had complete resolution of neurologic symptoms at three-month follow-up
Molecular determinants of the aggregation behavior of alpha- and beta-synuclein
alpha- and beta-synuclein are closely related proteins, the first of which is associated with deposits formed in neurodegenerative conditions such as Parkinson's disease while the second appears to have no relationship to any such disorders. The aggregation behavior of alpha- and beta-synuclein as well as a series of chimeric variants were compared by exploring the structural transitions that occur in the presence of a widely used lipid mimetic, sodium dodecyl sulfate (SDS). We found that the aggregation rates of all these protein variants are significantly enhanced by low concentrations of SDS. In particular, we inserted the 11-residue sequence of mainly hydrophobic residues from the non-amyloid-beta-component (NAC) region of alpha- synuclein into beta-synuclein and show that the fibril formation rate of this chimeric protein is only weakly altered from that of beta-synuclein. These intrinsic propensities to aggregate are rationalized to a very high degree of accuracy by analysis of the sequences in terms of their associated physicochemical properties. The results begin to reveal that the differences in behavior are primarily associated with a delicate balance between the positions of a range of charged and hydrophobic residues rather than the commonly assumed presence or absence of the highly aggregation-prone region of the NAC region of alpha-synuclein. This conclusion provides new insights into the role of alpha-synuclein in disease and into the factors that regulate the balance between solubility and aggregation of a natively unfolded protein