High-resolution ultrasonography in assessment of nail-related disorders

Ultrasound of Nails: Why, How, When

Nail disorders are frequently a challenge to diagnose correctly only based on clinical findings. Moreover, biopsies may leave scars due to damage to the nail matrix. Currently, high-frequency ultrasound (HFUS) with probes >15 MHz is the first-choice imaging technique to study the nail. Compared with other imaging tests such as computed tomography and magnetic resonance imaging, HFUS has the advantage of high-resolution imaging of the nail apparatus without exposure to radiation, contrast media, and the risk of claustrophobia of these other expensive imaging methods. Notably, the axial spatial resolution of HFUS is higher than computed tomography and magnetic resonance imaging; therefore, it can better discriminate the anatomical alterations. Our objective is to review the main applications of HFUS of the nail through literature analysis and illustration of cases of the most frequent pathologies found in our experience, exemplifying why, how, and when HFUS could help diagnose nail diseases.

High-frequency ultrasonography for subungual glomus tumor evaluation - imaging findings

OBJECTIVE

This article aimed to describe the common imaging features of subungual glomus tumors.

METHODS

The study involved data collected between January 2019 and December 2022. Twenty-three patients with a total of 31 glomus tumors underwent high-frequency ultrasound examinations with a 24-MHz probe. Two experienced radiologists independently evaluated the images, and only data from the more experienced radiologist were used for subsequent analyses.

RESULTS

The average size of the tumors was 4.6 mm, and most of them appeared homogeneously hypoechogenic (90.3%). Bone remodeling of the distal phalanx was observed in 87.1% of cases, with an average axial circumference loss of 0.8 mm, indicating the slow and expansive growth of glomus tumors. Intense vascularization was found in 54.8% of cases on Doppler images, and the stalk sign, reflecting the vascular origin of the tumor, was present in 64.5% of cases. The most common clinical feature was pain, reported in 84.6% of cases, with a mean pain scale score of 7.0, indicating a negative impact on patients' lives despite being benign tumors.

CONCLUSION

The study concludes that ultrasound evaluation is highly useful for diagnosing glomus tumors, especially when multiple findings, such as bone remodeling, hypervascularization, and the stalk sign, are present. This method allows for accurate diagnosis, observation of periungual structures, and proper surgical planning, ultimately reducing recurrence rates.

Ultrasound and magnetic resonance image findings in a patient with a subungual abscess: A case report

Subungual abscesses are rare, and information about them through imaging findings is lacking. Carbon dioxide laser drainage and antibiotics are effective treatment strategies for subungual abscesses. We report a case of a 47-year-old male healthcare worker with a subungual abscess that improved after manual drainage alone. Ultrasound and magnetic resonance images showed a tumor (with blood flow) between the nail plate and distal phalanx. Culture tests revealed Staphylococcus aureus. The patient's symptoms resolved quickly and the nail returned to normal after 4 months. This is possibly the first report of a subungual abscess with ultrasound and magnetic resonance imaging findings.

The EFSUMB Guidelines and Recommendations for Musculoskeletal Ultrasound - Part I: Extraarticular Pathologies

The first part of the guidelines and recommendations for musculoskeletal ultrasound, produced under the auspices of the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB), provides information about the use of musculoskeletal ultrasound for assessing extraarticular structures (muscles, tendons, entheses, ligaments, bones, bursae, fasciae, nerves, skin, subcutaneous tissues, and nails) and their pathologies. Clinical applications, practical points, limitations, and artifacts are described and discussed for every structure. After an extensive literature review, the recommendations have been developed according to the Oxford Centre for Evidence-based Medicine and GRADE criteria and the consensus level was established through a Delphi process. The document is intended to guide clinical users in their daily practice.

A standardized sonographic analysis of nails in psoriatic arthritis and healthy controls: Feasibility, reliability, diagnostic performance, and demographic and clinical associations

OBJECTIVES

Subunits of the nail can be evaluated by nail ultrasonography (NUSG). The purposes of this study are to document NUSG properties (both nail-based and participant-based evaluations) in patients with psoriatic arthritis (PsA) and healthy controls and to explore the final scorings.

METHODS

After the literature review and a pilot study, a consensus was reached to evaluate 12 nails and 5 parameters by NUSG: nail plate impairment (NPI), nail plate thickness (NPT), nail bed thickness (NBT), nail thickness (NT), and Doppler activity (DA); further, scorings for each parameter (NPIs, NPTs, NBTs, NTs, and DAs) were calculated. Group comparisons and diagnostic performances (with ROC curve analysis) were applied to both parameters and scorings. Final scorings to predict PsA diagnosis among the NUSG scorings were reached by regression analysis. Feasibility, reliability, and clinical associations of the scores were also performed.

RESULTS

Sixty-four patients with PsA and 26 controls (3240 baseline images) were assessed. The most affected nails, PsA/control comparisons, and the ROC analysis varied among the nails, within the higher values of PsA; therefore, 12 nails remained in the scorings. Participant-based scorings showed better content and diagnostic performances than the nail-based. Diagnostic performances, feasibility, reliability, and regression analysis of the scorings documented that NPIs, NTs, and DAs were the best. Some demographics, employee status, hemoglobin, and disease activity of the participants were associated with them.

CONCLUSIONS

The NUSG Index (NUSGI) including NPIs, NTs, and DAs is a feasible, reliable, and discriminative method to predict PsA diagnosis, with its rich content. Clinicaltrials.gov-ID: NCT04718428.

Nail unit ultrasound: a complete guide of the nail diseases

INTRODUCTION

The nails have a functional and esthetic importance for patients. Almost always, the nail disorders are diagnosed on the basis of clinical findings, but imaging methods may be required for a better assessment. These imaging methods, such as ultrasound and magnetic resonance, may help to establish an accurate diagnosis. Magnetic resonance imaging is not widely available and sometimes may be very expensive; that is why, ultrasound is an excellent imaging modality. Our objective is to expose the nail unit anatomy, the nail unit anatomy in ultrasound, and some of the frequent pathologies found in our daily practice.

METHODS

A review of the literature was done to review the anatomy, technical aspects, and different findings in normal and abnormal nail unit ultrasound.

RESULTS

Ultrasound offers an appropriate alternative for the evaluation of the nail unit, allows a real-time evaluation of each one of the components of the nail unit with an optimal visualization of these structures, and allows the evaluation of the thickness of the components, the vascularity, and blood flow by Doppler application. In addition, the nail unit disorder, such as infectious diseases, inflammatory and rheumatologic conditions, nail tumors, among others, may be assessed, not only in the diagnosis but also in the follow-up. Pre-surgical evaluation, surgical follow-up, and some procedures, such as biopsies, may be done by this technique.

CONCLUSIONS

Ultrasound is an excellent technique for evaluation of normal anatomy, diagnosis, and follow-up of patients with nail unit diseases. This is an alternative for other imaging methods and may be used for an accurate diagnosis approach.