Clinical Applications for Microvascular Assessment


Modulim’s patented spatial frequency domain imaging (SFDI) technology is useful in applications where clinicians need timely, accurate, noninvasive, quantitative assessment of hemoglobin distribution and oxygenation. Background and use cases for SFDI were recently highlighted in a review article.



SFDI can help providers with clinical insights like these:


Diabetic foot ulcers & PAD


Poor peripheral circulation in diabetes patients accelerates silent vascular changes and can lead to a diabetic foot ulcer (DFU) and Peripheral Arterial Disease (PAD). The end result for the patient is often an amputation. DFUs are common (34% of diabetes patients get an ulcer in their lifetime), costly, and debilitating (Armstrong et al., 2017). Unfortunately, PAD is underdiagnosed due to a lack of noninvasive testing. To facilitate targeted intervention before an amputation is needed, our technology measures peripheral perfusion and allows clinicians to better manage their patients’ complications.


Recent publications show:

  • SFDI was used to identify unique signatures of compromised circulation in diabetes and PAD patients (Weinkauf et al., 2019).

  • SFDI was used to identify high risk patients in a larger population with the goal of risk stratification (Lee et al., 2020).

  • SFDI was used to differentiate the etiology (neuropathic vs. neuro-ischemic) of DFUs (Murphy et al., 2020).

  • SFDI Was used to stratify severity of microvascular disease (Jett et al., 2021).

  • SFDI was used to differentiate the etiology (neuropathic vs. neuro-ischemic) of DFUs (Murphy et al., 2020).

Pressure ulcers


Immobile patients suffer from constant pressure on specific areas, resulting in ulcers that often cause pain and are difficult to heal. Pressure ulcers (or decubitus ulcers) are persistent and costly problems in hospitals, nursinghomes, and long-term care facilities. The mitigation strategy often involves constant rotation of patients, which uses the time and resources of care providers. Modulim’s SFDI technology can help clinicians monitor circulation changes that precede ulcers and allow caregivers to intervene proactively. If an ulcer has already formed, SFDI technology can help clinicians track and document the impact of treatment attempts. A recent publication demonstrated how SFDI was used as a tool for skin assessment in subjects at risk for pressure ulcers (Yafi et al. 2017).

Reconstructive surgical flaps


Proper oxygenation and perfusion are critical for successful reconstructive flap procedures following mastectomies or other surgeries with pedicle flaps or free tissue transfer flaps. Although there are different ways to measure perfusion, the current standard of care relies on the subjective evaluation of tissue discoloration and temperature. SFDI provides clinicians a wide-field distribution of perfusion without the use of contrast agents. This information can enable clinicians to perform preoperative planning, intra-operative validation of successful attachment, and post-operative monitoring. A publication from 2013 showed SFDI being used for the assessment of flaps in mastectomy procedures (Gioux et al., 2013).



Treatment of burns depends on an accurate diagnosis of a wound’s severity. Unfortunately, even experts incorrectly diagnose partial thickness burns a third of the time because evaluation is based on visual inspection of wound coloring, tissue necrosis, burn surface area, and edema.


Modulim’s SFDI technology can assess the structure and function of tissue in burn areas quantitatively. Recent peer-reviewed studies have shown: