Table 1.
Comparisons of commercially available handheld ultrasound instruments.
Fig 1.
Diagrams of the 10MHz EyeCubed v3 and Butterfly iQ devices and example images.
Images obtained from a healthy volunteer with the 10MHz EyeCubed v3 and Butterfly iQ devices are outlined in orange and blue respectively.
Fig 2.
Designs of the polymer molds and diagrams of the phantoms produced.
a) Polymer mold designs and side profile images of the printed polymers. Mold A was designed to compare lateral resolution with decreasing feature lateral separation. Mold B also compared lateral resolution but with decreasing feature width. Mold C examined axial resolution with decreasing feature heights. Mold D also investigated axial resolution by decreasing vertical separation of features. b) Diagrams of phantoms produced using the polymer molds. The molds were embedded in gelatin and imaged as high acoustic reflectivity phantoms. The molds were subsequently removed from the gelatin, leaving a gelatin imprint of the mold. Gelatin imprints from each mold were submerged in water and imaged as low acoustic reflectivity phantoms. *Correspond to features that were not preserved during removal of the polymer mold and were therefore unavailable for comparison.
Fig 3.
Diagrams of phantoms and images taken with Butterfly iQ and COU.
High acoustic reflectivity polymer molds (designs listed in Fig 1) were embedded in gelatin and compared in rows a-c. Low acoustic reflectivity gelatin imprints, created by removing the molds, are compared in rows d-g. White arrowheads indicate the horizontal positions of phantom features on the diagrams and corresponding ultrasound images. The red arrowheads in row a highlight the differences observed in the 0.4 mm lateral feature separation in Mold A between Butterfly iQ (blue) and COU (orange). The red arrowheads in row d indicate gelatin features that were not preserved upon removing Mold A from its embedded gelatin.
Fig 4.
Example images and Likert scale featured in the survey.
a) Select images of pathologies featured in the survey, including intraocular silicone oil and tractional retinal detachment. COU images are seen in the orange outline, whereas Butterfly iQ images with the PL, MSK-ST, MSK, and N presets are displayed with the blue outline. b) Likert scale used by graders to evaluate images for resolution, detail, image quality, and diagnostic confidence.
Table 2.
Results of Kruskal-Wallis analysis on survey responses.