USFDA Med. Device: Guidance on Laser Products, Diagnostics, X-ray & Ultrasonic Diathermy Devices
The Center for Devices and Radiological Health released multiple guidances earlier today (21-February-2023), related to "Laser Products, Diagnostics, X-ray & Ultrasonic Diathermy Devices".
Guidance: Marketing Clearance of Diagnostic Ultrasound Systems and Transducers
In this guidance, FDA provides detailed recommendations on how to submit 510(k)s for diagnostic ultrasound devices and transducers and describes the types of modifications a diagnostic ultrasound device can make without requiring a premarket notification (510(k)).

Diathermy is the controlled production of "deep heating" beneath the skin in the subcutaneous tissues, deep muscles, and joints for therapeutic purposes.
As part of this guidance document, recommendations are provided for 510(k) submissions of ultrasonic diathermy devices, also referred to as physiotherapy devices. In addition, certain International Electrotechnical Commission (IEC) standards are recommended for generating information for these devices that can be used to support 510(k) submissions.
Guidance: Medical X-Ray Imaging Devices Conformance with IEC Standards
As part of this guidance, FDA seeks to align performance standards prescribed by Subchapter C (Electronic Product Radiation Control (EPRC)) with IEC standards, where applicable and offers recommendations on how to comply with the applicable requirements to the industry.
Guidance: Performance Standard for Diagnostic X-Ray Systems and Their Major Components Small Entity Compliance Guide
The term “Performance Standards” will be used to refer to these regulations collectively known as the Performance Standards for Diagnostic X-ray Systems and Their Major Components.
To assist small entities to comply with these changes in the performance standard, the FDA has prepared this Small Entity Compliance Guide.