Optic Nerve Sheath Diameter Measured by Point-of-Care Ultrasound and MRI.

BACKGROUND AND PURPOSE: Ultrasound (US) measurement of the optic nerve sheath diameter (ONSD) and optic nerve diameter (OND) is a method frequently used to screen for an increased intracranial pressure. The aim of this study was to assess the accuracy of US measurements of ONSD and OND, when compared to magnetic resonance imaging (MRI) measurements as the criterion standard. METHODS: In this prospective, single-institution study, orbital US was performed for those patients requiring an emergent brain MRI. ONSD and OND of both eyes were measured in the axial and coronal planes in straight gaze by US. ONSD and OND from brain and orbital MRI were measured by two neuroradiologists. Correlation and agreement between readings were assessed using Pearson's correlations. RESULTS: Eighty-two patients met inclusion criteria. The mean axial and coronal ONSD in the MRI examinations was 5.6 and 5.7 mm at 3-5.9 mm behind the globe, respectively. The mean ONSD from the US measurements was 6.22 and 5.52 mm in the axial and coronal planes, respectively. The mean OND in US examinations was 4.31 mm (axial) and 3.68 mm (coronal). Axial versus coronal measurements of ONSD had a modest correlation in US assessment with an r2 of .385 (P < .001) but there were no correlations between any of the US and MRI measurements. CONCLUSIONS: In measuring ONSD and OND, US measurements showed a modest correlation between axial and coronal measurements, but no concordance was found between US and MRI in our setting.

Diagnostic Accuracy and Time-Saving Effects of Point-of-Care Ultrasonography in Patients With Small Bowel Obstruction: A Prospective Study.

STUDY OBJECTIVE: We evaluate the accuracy of point-of-care ultrasonography compared with computed tomographic (CT) scan and assess the potential time-saving effect of point-of-care ultrasonography in diagnosing small bowel obstruction. METHODS: This was a prospective observational study of a convenience sample of patients with suspected small bowel obstruction in an academic emergency department (ED). Physician sonographers were blinded to clinical data, laboratory results, and CT scan findings. Point-of-care ultrasonographic findings of small bowel obstruction was the primary outcome, defined as bowel-loop diameter greater than or equal to 25 mm with abnormal peristalsis. Maximum bowel dilatation, visible peristalsis, interluminal free fluid, and bowel wall thickness were evaluated. Time to completion of imaging results was abstracted from the medical records for each imaging modality. RESULTS: The study included 125 patients (median age 54.0 years [interquartile range 43 to 63 years]; 46% men), of whom 32 (25.6%) had small bowel obstruction, and 9 (7.2%) underwent surgery for it. Overall, the sensitivity of point-of-care ultrasonography for small bowel obstruction was 87.5% (95% confidence interval 71.0% to 96.5%), and specificity was 75.3% (95% confidence interval 65.2% to 83.6%). The area under the receiver operating characteristic curve to accurately predict small bowel obstruction was 0.74 (95% confidence interval 0.66 to 0.82). Results were similar across evaluated subgroups, including physician training level. The average time to obtain a CT scan report was 3 hours, 42 minutes; obtaining an abdominal radiograph took 1 hour, 38 minutes; and the mean elapsed time to complete point-of-care ultrasonography was 11 minutes. CONCLUSION: In ED patients with suspected small bowel obstruction, point-of-care ultrasonography has a reasonably high accuracy in diagnosing small bowel obstruction compared with CT scan, and may substantially decrease the time to diagnosis.

Enhanced Point-of-Care Ultrasound Applications by Integrating Automated Feature-Learning Systems Using Deep Learning.

Recent applications of artificial intelligence (AI) and deep learning (DL) in health care include enhanced diagnostic imaging modalities to support clinical decisions and improve patients' outcomes. Focused on using automated DL-based systems to improve point-of-care ultrasound (POCUS), we look at DL-based automation as a key field in expanding and improving POCUS applications in various clinical settings. A promising additional value would be the ability to automate training model selections for teaching POCUS to medical trainees and novice sonologists. The diversity of POCUS applications and ultrasound equipment, each requiring specialized AI models and domain expertise, limits the use of DL as a generic solution. In this article, we highlight the most advanced potential applications of AI in POCUS tailored to high-yield models in automated image interpretations, with the premise of improving the accuracy and efficacy of POCUS scans.

Ultrasound-guided intravenous access in adults using SonoStik®, a novel encapsulated sterile guidewire: A prospective cohort trial.

PURPOSE: We evaluated the performance of an encapsulated guidewire designed for single-handed use with ultrasound-guided vascular access (SonoStik) with Seldinger technique, as compared with conventional intravenous catheters placed under ultrasound guidance in healthy subjects. METHODS: This is a prospective cohort trial in healthy subjects in which each subject served as his/her own control by having a SonoStik ultrasound intravenous cannulation placed in one arm and a conventionally placed, standard ultrasound intravenous cannulation placed in the other arm. The basilic vein was used because it is a non-visible and non-palpable vein. Emergency department technicians with extensive experience in ultrasound-guided intravenous access performed the procedures. The first-attempt success rate of intravenous-guided intravenous by using the SonoStik was compared to the standard ultrasound intravenous cannulation in adult healthy subjects. The secondary outcomes including time of procedure, technicians' and subjects' satisfaction, and complications were compared in both arms of the study. RESULTS: A total of 24 volunteers with a mean age of 22.7 years were enrolled. Four emergency department technicians with extensive prior experience with ultrasound-guided intravenous access but with no prior experience using the SonoStik device performed the procedures. The first-attempt success was 83.3% with the use of SonoStik ultrasound intravenous cannulation compared to 95.8% with the standard ultrasound intravenous cannulation. There was a mean of 1.14 insertions per each successful placement in the SonoStik group compared to 1.04 insertions by using the standard catheters (mean differences = -0.1; 95% confidence interval = -0.6 to 0.4). There were no complications in either SonoStik or the standard ultrasound intravenous cannulation group. The mean time of insertion using SonoStik was slightly longer compared to standard ultrasound intravenous cannulation (143.3 vs 109.7 s). CONCLUSION: This study demonstrated that emergency department technicians skilled in ultrasound-guided intravenous access could successfully place SonoStik 83.3% of the time in vessels that were unable to be palpated or visualized. Compared to standard ultrasound intravenous cannulation, the odds ratio of successful cannulation with SonoStik was 0.91 (95% confidence interval = 0.04-17.5). In all cases, the time required to successfully insert SonoStik was less than 4 min from tourniquet application to catheter advancement to hub, with a mean time of less than 2.5 min.