Photoplethysmography-new applications for an old technology: a sleep technology review.

Unlabelled: Education is integral to the American Academy of Sleep Medicine (AASM) mission. The AASM Emerging Technology Committee identified an important and evolving piece of technology that is present in many of the consumer and clinical technologies that we review on the AASM #SleepTechnology (https://aasm.org/consumer-clinical-sleep-technology/) resource-photoplethysmography.

Knuckle cracking at night associated with sodium oxybate treatment.

During upward titration of a dose of sodium oxybate therapy for narcolepsy with cataplexy, a 25-year-old woman was observed by her husband to have new onset of knuckle-cracking and moaning behaviors during sleep ≥1 nights each week. The patient did previously occasionally crack her knuckles during the day (but never at night). These behaviors had not been evaluated by polysomnography.

There is more to an elevated bicarbonate.

Hadigal S, Ryals S, Wagner M, Berry R. There is more to an elevated bicarbonate. .

An unusual case of PAP-related eye dryness.

Ryals S, Sharma S, HAdigal S, Wagner M, Berry R. An unusual case of PAP-related eye dryness. .

A case of treatment-emergent central sleep apnea?

Ryals S, McCullough L, Wagner M, Berry R, Dibra M. A case of treatment-emergent central sleep apnea? . 2020;16(2):331–334.

Use of a Transformed ECG Signal to Detect Respiratory Effort During Apnea.

Study Objectives: To evaluate the ability of a transformed electrocardiography (ECG) signal recorded using standard electrode placement to detect inspiratory bursts from underlying surface chest wall electromyography (EMG) activity and the utility of the transformed signal for apnea classification compared to uncalibrated respiratory inductance plethysmography (RIP).

Methods: Part 1: 250 consecutive adult studies without regard to respiratory events were retrospectively reviewed. The ECG signal was transformed with high pass filtering and viewed with increased sensitivity and channel clipping to determine the fraction of studies with inspiratory burst visualization as compared to chest wall EMG (right thorax).

Use of Chest Wall EMG to Classify Hypopneas as Obstructive or Central.

Study Objectives: To compare classification of hypopneas as obstructive or central based on an effort signal derived from surface chest wall electromyography (CW-EMG-EF) coupled with airflow amplitude versus classification using The AASM Manual for the Scoring of Sleep and Associated Events: Rules, Terminology and Technical Specifications (AASM Scoring Manual) criteria; and to characterize hypopneas classified as obstructive versus central using a resistance surrogate.

Methods: CW-EMG was recorded in the eighth intercostal space at the right midaxillary line. Five hypopneas were randomly selected from 65 consecutive adult clinical positive airway pressure titration studies meeting study criteria.

The feasibility of gamma radiation sterilization for decellularized tracheal grafts.

Objectives/hypothesis: The most promising stem cell-derived tracheal transplantation approach is dependent upon the use of decellularized tracheal grafts. It has been assumed that a sterilization step, such as gamma radiation, would damage the delicate extracellular matrix of the graft, thus rendering it less viable for cellular repopulation, although this has not been thoroughly investigated.

Study Design: Laboratory-based comparative analysis.

Use of Chest Wall Electromyography to Detect Respiratory Effort during Polysomnography.

Study Objectives: To evaluate the ability of chest wall EMG (CW-EMG) using surface electrodes to classify apneas as obstructive, mixed, or central compared to classification using dual channel uncalibrated respiratory inductance plethysmography (RIP).

Methods: CW-EMG was recorded from electrodes in the eighth intercostal space at the right mid-axillary line. Consecutive adult clinical sleep studies were retrospectively reviewed, and the first 60 studies with at least 10 obstructive and 10 mixed or central apneas and technically adequate tracings were selected.

Clinical utility of inappropriate positron emission tomography myocardial perfusion imaging: test results and cardiovascular events.

Background: Appropriate use criteria for myocardial perfusion imaging (MPI) were developed to categorize scenarios where MPI might be beneficial (appropriate) or not (inappropriate). Few investigations have evaluated the clinical utility of this categorization strategy, particularly with positron emission tomography (PET) MPI.

Methods And Results: We conducted this retrospective cohort investigation in a Veterans Affairs (VA) medical center, on predominantly male subjects who underwent PET-MPI.

A case report highlighting the growing trend of Internet-based self-diagnosis of "Morgellon's disease".

"Morgellon's Disease" is a term used to describe a bizarre condition characterized by the belief that strange sensations in the skin are due to filaments called "Morgellon's Bodies."' The focus of this case report is to inform readers of the growing incidence of this psychosomatic condition. Unfortunately, self-diagnosis has become increasingly common because of the widespread coverage on the Internet.