Ultra-high-frequency ultrasound and machine learning approaches for the differential diagnosis of melanocytic lesions.

Malignant melanoma (MM) is one of the most dangerous skin cancers. The aim of this study was to present a potential new method for the differential diagnosis of MM from melanocytic naevi (MN). We examined 20 MM and 19 MN with a new ultra-high-frequency ultrasound (UHFUS) equipped with a 70 MHz linear probe. Ultrasonographic images were processed for calculating 8 morphological parameters (area, perimeter, circularity, area ratio, standard deviation of normalized radial range, roughness index, overlap ratio and normalized residual mean square value) and 122 texture parameters. Colour Doppler images were used to evaluate the vascularization. Features reduction was implemented by means of principal component analysis (PCA), and 23 classification algorithms were tested on the reduced features using histological response as ground-truth. Best results were obtained using only the first component of the PCA and the weighted k-nearest neighbour classifier; this combination led to an accuracy of 76.9%, area under the ROC curve of 83%, sensitivity of 84% and specificity of 70%. The histological analysis still remains the gold-standard, but the UHFUS images processing using a machine learning approach could represent a new non-invasive approach.

Ultra-high frequency ultrasonography (UHFUS)-guided minor salivary gland biopsy: A promising procedure to optimize labial salivary gland biopsy in Sjögren's syndrome.

BACKGROUND: Sjögren's syndrome (SS) is an autoimmune disease characterized by an inflammatory infiltrate of exocrine salivary and lachrymal glands. Diagnosis is complex, and minor salivary gland biopsy and subsequent focus score (FS) calculation appear of extreme importance in the diagnostic work-up of the disease. Ultra-high frequency ultrasonography (UHFUS) is a recently introduced diagnostic technique, which is gaining an increasingly important role in intraoral imaging. This study aims at exploring the usefulness of UHFUS for obtaining valuable labial salivary gland samples to assess the histopathological features of SS patients. METHODS: Patients with clinical suspect of SS and eligible for minor salivary gland biopsy were enrolled. UHFUS scan of the lower lip was performed. Glandular echostructure was classified according to Outcome Measures in Rheumatology (OMERACT) scoring system. The glands to be sampled were selected on the basis of UHFUS evaluation and biopsied. The areas of the samples were recorded and compared with those obtained without UHFUS guidance. The correlation between UHFUS grade and labial gland FS was also assessed. RESULTS: The areas of the samples obtained with UHFUS guidance were significantly higher (7.25 ± 3.98 mm2 ) than those obtained by conventional procedures (5.79 ± 3.49 mm2 , P = .02). UHFUS correlated significantly with the salivary gland FS (r = .532, P = .001). CONCLUSION: UHFUS seems a promising tool in SS diagnostic algorithm, being able to provide a valuable support to the biopsy procedure. Further studies are mandatory to confirm the role of UHFUS in SS.

Ultrasound-guided injection of intralesional steroids in acute hidradenitis suppurativa lesions: A prospective study.

The management of hidradenitis suppurativa (HS) flares with intralesional steroids lacks strong scientific evidence but limited data suggest that it may be useful. The objective of this study is to assess the clinical and ultrasound responses of HS flares to ultrasound-guided injections of intralesional triamcinolone (40 mg/ml) with a dilution 1:4 versus 1:2 at 30-day (t1), 60-day (t2), and 90-day (t3) follow-up. We recruited patients with ≤3 acute lesions, unresponsive to topical therapy. At baseline we assessed lesions clinically and by ultra-high frequency ultrasound (48 or 70 MHz) and randomly performed an ultrasound-guided injection of triamcinolone. Assessments were repeated at t1, t2, and t3 follow-up, re-injecting the lesion in the case of no or partial response. We treated 49 lesions: 38.8% showed improvements at t1; 46.9% at t2; 6% at t3; and 8.3% showed no clinical and ultrasound improvements. Long-term follow-up data confirmed a statistically significant reduction in Visual Analogue Scale (VAS)-pain, Dermatology Life Quality Index (DLQI), and HS-Physician Global Assessment (HS-PGA), as well as edema and vascular signals. No adverse effects were reported. Our study suggests that ultrasound-injections with a 1:2 dilution are beneficial for HS flares that do not respond to topical treatment and should be included in the therapeutic algorithm.

Ultra-high frequency ultrasound in the differential diagnosis of oral pemphigus and pemphigoid: An explorative study.

OBJECTIVES: Intraoral ultra-high frequency ultrasound (UHFUS) is an emerging technique in oral medicine, due to its possibility to provide submillimeter resolution imaging of superficial mucosal structures. In this study, the potential role of UHFUS in the diagnosis of oral pemphigus vulgaris (PV) and mucous membrane pemphigoid (MMP) is assessed. MATERIALS AND METHODS: Consecutive patients with suspected oral PV or MMP were enrolled. All patients underwent clinical examination, laboratory tests, intraoral UHFUS scan, and biopsy. Histology and direct immunofluorescence were set as benchmark for diagnosis confirmation. The sensitivity and specificity of UHFUS compared to histology were assessed. Mann-Whitney test was performed to evaluate the presence of differences in the echogenicity of PV and MMP. P-value was set at P < 0.05. RESULTS: Twenty-five patients were included. Thirteen patients were diagnosed with PV, and twelve with MMP. The UHFUS features of PV and MMP lesions were described. Image analysis showed statistically significant differences between the echogenicity of PV and MMP lesions (P < 0.05). Good concordance between UHFUS and histology was found. UHFUS showed 75% sensitivity in the diagnosis of PV and 66.7% in the diagnosis of MMP. CONCLUSIONS: UHFUS appears a valuable tool in the diagnosis of PV and MMP. Although histology and immunofluorescence remain the gold standard, UHFUS role in the diagnostic algorithm of PV and MMP seems promising as a chair-side tool consistently enhancing clinical evaluation of oral bullous lesions.

Ultra-High Frequency Ultrasound, A Promising Diagnostic Technique: Review of the Literature and Single-Center Experience.

OBJECTIVES: Ultra-high frequency ultrasonography (UHFUS) is a recently introduced diagnostic technique which finds several applications in diverse clinical fields. The range of frequencies between 30 and 100 MHz allows for high spatial resolution imaging of superficial structures, making this technique suitable for the imaging of skin, blood vessels, musculoskeletal anatomy, oral mucosa, and small parts. However, the current clinical applications of UHFUS have never been analyzed in a consistent multidisciplinary manner. The aim of this study is to revise and discuss the current applications of UHFUS in different aspects of research and clinical practice, as well as to provide some examples of the current work-in-progress carried out in our center. MATERIALS AND METHODS: A literature search was performed in order to retrieve articles reporting the applications of UHFUS both in research and in clinical settings. Inclusion criteria were the use of frequencies above 30 MHz and study design conducted in vivo on human subjects. RESULTS: In total 66 articles were retrieved. The majority of the articles focused on dermatological and vascular applications, although musculoskeletal and intraoral applications are emerging fields of use. We also describe our experience in the use of UHFUS as a valuable diagnostic support in the fields of dermatology, rheumatology, oral medicine, and musculoskeletal anatomy. CONCLUSION: Ultra-high frequency ultrasonography application involves an increasing number of medical fields. The high spatial resolution and the superb image quality achievable allow to foresee a wider use of this novel technique, which has the potential to bring innovation in diagnostic imaging.

Ultra-high frequency ultrasonography of labial glands is a highly sensitive tool for the diagnosis of Sjögren's syndrome: a preliminary study.

OBJECTIVES: Ultra-high frequency ultrasonography (UHFUS) has been recently introduced in oral medicine due to its ability to image small anatomical structures including labial salivary glands (LSG). To date no ultrasonography morphological studies of labial salivary glands (LSG) have been carried out in SS. In this pilot study we aimed at analysing the distribution of UHFUS findings in LSG of patients with suspected SS, focusing in particular on the association with patients' oral dysfunction, antibody profiles and histopathology. METHODS: Consecutive patients undergoing a LSG biopsy for clinically suspected SS were included in this study between January 2018 and January 2020. Intraoral UHFUS scan of the lip mucosa was performed with Vevo MD equipment, using a 70 MHz probe with a standardised protocol. LSG were assessed by using a four-grade semiquantitative scoring system (0-3), similar to the OMERACT scoring system used for major salivary glands. The distribution of UHFUS grades was compared in patients stratified according their final diagnosis, patients antibody profiles and LSG histopathology. RESULTS: We included 128 patients with suspected SS: out of them, 54 (42.2%) received a final diagnosis of SS, made according to the ACR 2016 criteria and 74 (57.8%) were diagnosed as no-SS sicca controls. We found that LSG inhomogeneity was significantly greater in patients with SS than in no-SS subjects (p<0.0001). We also found that higher UHFUS pattern of inhomogeneity (i.e. grade 2 and 3) were significantly more frequent in both SSA+/SSB- and SSA+/SSB+ patients (p=0.001). A normal UHFUS pattern, by contrast, was significantly more common in SSA-/SSB- subjects (i.e. 15/83 (18.1%) vs. 1/33 (3%) vs. 0/12 (0%), p=0.001). Finally, LSG inhomogeneity was significantly associated with both the number of foci (p<0.001) and focus score (p<0.001). Particularly, we found that both the number of foci and the FS were significantly higher in patients presenting a UHFUS grading of 2 and 3 with respect to those presenting a UHFUS grading of 0 and 1 (p=0.01). CONCLUSIONS: This preliminary study demonstrates the optimal feasibility of UHFUS and its high sensitivity in identifying negative patients on subsequent lip biopsy, thus avoiding invasive procedures in selected cases. Further studies are in progress to define the clinical and predictive role of the various patterns observed and their added value with respect to traditional salivary gland ultrasonography.

Intraoral Ultra-High Frequency Ultrasound study of oral lichen planus: A pictorial review.

BACKGROUND: Ultra-High Frequency Ultrasound (UHFUS) is a recently introduced diagnostic technique involving the use of higher frequencies compared to conventional ultrasound. Among the several fields of application, intraoral usage of UHFUS appears still limited. We report the intraoral evaluation of Oral Lichen Planus (OLP) by means of UHFUS and describe typical UHFUS aspect of different forms of presentation of OLP. MATERIALS AND METHODS: Patients with clinical and histological diagnosis of OLP were enrolled in the study. OLP lesions were evaluated by means of intraoral UHFUS performed at 70 MHz, using B-mode and C-mode, in order to characterize the echostructure of each form of presentation. RESULTS: Fifty patients in total were enrolled, and UHFUS features were described for different OLP forms. All the lesions showed a thick, hypoechoic superficial layer in the mucosal stratum, suggesting that such UHFUS alteration can be pathognomonic of OLP. CONCLUSION: Ultra-High Frequency Ultrasound was able to differentiate superficial alterations of the oral mucosa, giving insight on possible applications of UHFUS in the study of OLP beyond clinical and histological investigations. Due to a limited study sample, we cannot draw firm conclusions. However, it is reasonable to think that UHFUS evaluation of OLP may provide useful information to the clinician.

Advanced evaluation of hidradenitis suppurativa with ultra-high frequency ultrasound: A promising tool for the diagnosis and monitoring of disease progression.

BACKGROUND: Hidradenitis suppurativa is a chronic inflammatory skin disease. An ultrasound staging (SOS-HS) using frequencies from 7 to 18 MHz has been proposed to evaluate the severity of the disease. MATERIALS AND METHODS: We retrospectively evaluated the most significant lesions in 50 patients with hidradenitis suppurativa (32 females and 18 males, aged from 12 to 68 years old), who had undergone high-frequency ultrasound (HFUS) (18-22 MHz) and ultra-high frequency ultrasound (UHFUS) (48 and 70 MHz). A MyLab™ Touch system (Esaote) equipped with a 18-22 MHz linear probe was used for the HFUS, and a Vevo® MD (VisualSonics) was used for the UHFUS, equipped with two linear probes (70 and 48 MHz). RESULTS: A total of 116 lesions were observed, of which 66 were fluid collections, 32 were tunnels, 6 pseudocysts, 5 bridge scars, 5 tombstone comedones, and 2 granulation tissues. Structures that had already been described with HFUS were then observed with UHFUS but with a better definition. In addition, structures that had not been detected by HFUS were also observed with UHFUS such as drop-shaped hair follicles, micro-tunnels, and microcysts. CONCLUSION: Ultra-high frequency ultrasound provides a better understanding of hidradenitis suppurativa. Patients can be monitored more effectively thereby preventing the most severe changes.

Feasibility of intraoral ultrasonography in the diagnosis of oral soft tissue lesions: a preclinical assessment on an ex vivo specimen.

OBJECTIVES: The early detection of oral soft tissue lesions is an important prognostic factor, and the possibility of using ultrasonography (US) as a diagnostic tool may improve the diagnosis and characterization of tissue alterations at an early stage. This study aims to evaluate the feasibility of intraoral US by performing a preclinical assessment of an ex vivo specimen in which focal lesions were simulated. MATERIALS AND METHODS: Fourteen lesions were simulated on a freshly extracted calf tongue, by introducing in the tongue different materials mimicking the appearance of various focal lesions. The specimen was scanned with a 8 MHz US probe and computed tomography (CT) was performed to compare the two imaging techniques. Later, the specimen was dissected to set a benchmark for size assessment. RESULTS: US was able to identify all the simulated lesions within the tongue, resulting in one case more accurate than CT. Statistical analysis demonstrated high correlation between the measurements of the simulated lesions performed on the US images and the real size of the materials introduced in the tongue (p < 0.05). CONCLUSIONS: This preclinical study proves that US performs well in the detection and characterization of simulated lesions of the tongue. These findings suggest that US could be effectively used in clinical applications. However, further research is mandatory to assess the reliability of in vivo US in the detection and characterization of tongue lesions as well as of other oral soft tissue alterations.

The Role of Ultra-High-Frequency Ultrasound in Pyoderma Gangrenosum: New Insights in Pathophysiology and Diagnosis.

Pyoderma gangrenosum (PG) is a neutrophilic dermatological disease, whose pathogenesis is still poorly clarified. Because of the lack of validated criteria for diagnosis and response, PG treatment is still challenging and should be differentiated in the inflammatory and non-inflammatory phases. Our study aimed to provide a new semi-quantitative approach for PG diagnosis and monitoring, identifying ultra-high-frequency ultrasound (UHFUS) early biomarkers associated with the transition between the two phases. We enrolled 13 patients affected by painful PG lesions evaluated during the inflammatory phase (T0) and during the non-inflammatory phase (T1): pain was measured by the Visual Analogue Scale (VAS); clinical features were recorded through digital photography; epidermis and dermis ultrasound (US) characteristics were evaluated by UHFUS examination with a 70 MHz probe (Vevo MD® FUJIFILM VisualSonics). In T1 UHFUS examination, the presence of hyperechoic oval structures was lower compared to T0 (p value < 0.05). An hyperechogenic structure within the oval structure, suggestive of a hair tract, was evident in T0 and absent in T1 (p value < 0.05). In T0, blood vessels appear as U-shaped and V-shaped anechoic structures with a predominance of U-shaped vessels (p value < 0.05) compared to the more regular distribution found in T1. Finding early biomarkers of the transition from the inflammatory to the non-inflammatory phase could provide new insight in terms of therapeutic decision making and response monitoring. The differences found by this study suggest a potential use of UHFUS for the development of an objective standardized staging method. Further investigations will be necessary to confirm our preliminary results, thus providing a turning point in PG early detection, differential diagnosis and treatment monitoring.

Multiparametric Skin Assessment in a Monocentric Cohort of Systemic Sclerosis Patients: Is There a Role for Ultra-High Frequency Ultrasound?

Background: To assess skin involvement in a cohort of patients with systemic sclerosis (SSc) by comparing results obtained from modified Rodnan skin score (mRSS), durometry and ultra-high frequency ultrasound (UHFUS). Methods: SSc patients were enrolled along with healthy controls (HC), assessing disease-specific characteristics. Five regions of interest were investigated in the non-dominant upper limb. Each patient underwent a rheumatological evaluation of the mRSS, dermatological measurement with a durometer, and radiological UHFUS assessment with a 70 MHz probe calculating the mean grayscale value (MGV). Results: Forty-seven SSc patients (87.2% female, mean age 56.4 years) and 15 HC comparable for age and sex were enrolled. Durometry showed a positive correlation with mRSS in most regions of interest (p = 0.025, ρ = 0.34 in mean). When performing UHFUS, SSc patients had a significantly thicker epidermal layer (p < 0.001) and lower epidermal MGV (p = 0.01) than HC in almost all the different regions of interest. Lower values of dermal MGV were found at the distal and intermediate phalanx (p < 0.01). No relationships were found between UHFUS results either with mRSS or durometry. Conclusions: UHFUS is an emergent tool for skin assessment in SSc, showing significant alterations concerning skin thickness and echogenicity when compared with HC. The lack of correlations between UHFUS and both mRSS and durometry suggests that these are not equivalent techniques but may represent complementary methods for a full non-invasive skin evaluation in SSc.

Abdominal Visceral-to-Subcutaneous Fat Volume Ratio Predicts Survival and Response to First-Line Palliative Chemotherapy in Patients with Advanced Gastric Cancer.

Prognosis in advanced gastric cancer (aGC) is predicted by clinical factors, such as stage, performance status, metastasis location, and the neutrophil-to-lymphocyte ratio. However, the role of body composition and sarcopenia in aGC survival remains debated. This study aimed to evaluate how abdominal visceral and subcutaneous fat volumes, psoas muscle volume, and the visceral-to-subcutaneous (VF/SF) volume ratio impact overall survival (OS) and progression-free survival (PFS) in aGC patients receiving first-line palliative chemotherapy. We retrospectively examined CT scans of 65 aGC patients, quantifying body composition parameters (BCPs) in 2D and 3D. Normalized 3D BCP volumes were determined, and the VF/SF ratio was computed. Survival outcomes were analyzed using the Cox Proportional Hazard model between the upper and lower halves of the distribution. Additionally, response to first-line chemotherapy was compared using the χ2 test. Patients with a higher VF/SF ratio (N = 33) exhibited significantly poorer OS (p = 0.02) and PFS (p < 0.005) and had a less favorable response to first-line chemotherapy (p = 0.033), with a lower Disease Control Rate (p = 0.016). Notably, absolute BCP measures and sarcopenia did not predict survival. In conclusion, radiologically assessed VF/SF volume ratio emerged as a robust and independent predictor of both survival and treatment response in aGC patients.

Ultrasound imaging for the rheumatologist. XLII. Assessment of hip pain in rheumatic patients: the radiologist's view.

Hip pain is a common complaint in daily practice and the identification of the underlying pathologic condition is the first step for an adequate treatment. In this review, we discuss the available evidence for the application of conventional radiography, computed tomography and magnetic resonance imaging in rheumatologic patients with painful hip, presenting the main imaging findings due to osteoarthritis, inflammatory arthritis (rheumatoid arthritis and spondyloarthritides), osteonecrosis and some other soft tissue involvement (bursitis and synovial cyst) that could be the cause of hip pain. Because different imaging techniques show different sensitivity and specificity, the choice of technique to use depends on the type and stage of the disease itself.

Ultra-high frequency ultrasound for digital arteries: improving the characterization of vasculopathy in systemic sclerosis.

OBJECTIVES: To provide a full characterization of proper palmar digital arteries (PPDA) in systemic sclerosis (SSc) with ultra-high frequency ultrasound (UHFUS), and to investigate possible relationships between digital macroangiopathy and microangiopathy. METHODS: SSc patients without active digital ulcers and healthy controls (HC) were enrolled. Each subject underwent UHFUS 70 MHz evaluation of PPDA from II to V fingers bilaterally, searching for vessel occlusion and measuring the thickness of the three arterial layers and the systolic-diastolic excursion range. Microcirculation was investigated with capillaroscopy and laser speckle contrast analysis (LASCA). RESULTS: Forty-six SSc patients (87% female, mean age 55.5 years) and 15 HC comparable for age and sex were enrolled. UHFUS in SSc revealed the occlusion of 124 (16.8%) PPDA, whereas in HC they were all patent. Considering a finger with at least one PPDA occluded as ultrasonographically pathological, 67.4% patients presented ≥1 pathological fingers. All three arterial layers were significantly thicker and excursion range significantly reduced in SSc than in HC (p<0.001 for all). Seventy-three percent of fingers previously affected by digital ulcers, were ultrasonographically pathological. Disease duration was directly correlated to the thickness of all three arterial layers. No significant correlations emerged between capillaroscopy or LASCA findings and UHFUS features. CONCLUSION: UHFUS allows the characterization of vasculopathic involvement of PPDA in SSc, also showing subclinical vasculopathy. The lack of correlations between UHFUS and capillaroscopy or LASCA likely mirrors non-overlapping vasculopathic processes. UHFUS evaluation of PPDA emerges as complementary to microcirculation assessment for a more accurate and complete characterization of SSc vasculopathy.

Validation and Feasibility of an Automated System for the Assessment of Vascular Structure and Mechanical Properties in the Digital Arteries: An Ultrahigh-Frequency Ultrasound Study.

Ultrahigh-frequency ultrasound (UHFUS) allows sharp visualization of human small muscular arteries. This may help in elucidating some aspects of the pathophysiology of arterial aging, such as the stiffness gradient between large and small conduit arteries and its consequences on the microcirculation, as well as vascular diseases affecting medium-sized arteries. However, UHFUS use is still limited, partly because of the lack of validated tools to quantify vascular structure and mechanical properties of small muscular arteries. In this validation study, scans of digital arteries were obtained with UHFUS (VevoMD, Visualsonics-Fujifilm, Toronto, ON, Canada), analyzed using Carotid Studio software (Quipu, Pisa, Italy) and compared with the manual measurement. Agreement between the two techniques on measures of diameter, distension and intima-media thickness (IMT) was evaluated using Bland-Altman analyses; inter- and intra-operator reproducibility was evaluated using coefficients of variation (CVs). Overall, no trend or significant bias was observed between Carotid Studio and manual analysis. All limits of agreement were acceptable. The intra-observer CV of diastolic diameter and IMT were 4.1% and 4.2%, respectively. The inter-observer CV for diastolic diameter and IMT were 7.3% and 5.4%, respectively. Intra- and inter-observer CVs for distension were higher (25.7% and 26.7%, respectively). These results suggest that the Carotid Studio software is a valid and reproducible tool to study UHFUS scans of digital arteries, with potential utility both in rare vascular diseases of medium-sized arteries and in the study of the pathophysiology of arterial aging in general.

Role of Baseline Computed-Tomography-Evaluated Body Composition in Predicting Outcome and Toxicity from First-Line Therapy in Advanced Gastric Cancer Patients.

Sarcopenia is recognised as a predictor of toxicity and survival in localised and locally advanced gastric cancer (GC). Its prognostication power in advanced unresectable or metastatic GC (aGC) is debated. The survival impact of visceral and subcutaneous fat distribution (visceral fat area (VFA)/subcutaneous fat area (SFA)) is ambiguous. Our aim was to determine the influence of body composition parameters (BCp) on toxicity and survival in aGC patients undergoing palliative treatment. BCp were retrospectively assessed by baseline computed tomography for 78 aGC patients who received first-line chemotherapy from March 2010 to January 2017. Correlations between BCp and toxicity and survival were calculated by χ2-test and by log-rank-test and Cox-model, respectively. Sarcopenia fails to show association with progression-free survival (PFS) (p = 0.44) and overall survival (OS) (p = 0.88). However, sarcopenia influences the development of high-grade neutropenia (p = 0.048) and mucositis (p = 0.054). VFA/SFA (high vs. all the rest) results as a strong predictor of objective response (p = 0.02) and outcome (PFS, p = 0.001; OS, p = 0.02). At multivariate analysis for PFS, prognostic factors are VFA/SFA (p = 0.03) and a neutrophil-lymphocyte ratio >3. The same factors remain significant for OS (each p = 0.03) along with Eastern Cooperative Oncology Group (ECOG) performance status (p = 0.008) and number of metastatic sites ≥2 (p < 0.001). In our cohort of aGC, VFA/SFA exhibit a robust impact on survival, with a higher sensitivity than sarcopenia.

Ultra-high frequency ultrasound (UHFUS) applications in Sjogren syndrome: narrative review and current concepts.

Primary Sjogren's syndrome (SS) is a systemic autoimmune chronic inflammatory disease with predominant involvement of the exocrine glands, particularly the salivary glands (SGs). The role of salivary glands ultrasound (SGUS) in the work-up of patients with primary Sjogren syndrome (SS) is progressively increasing due to its useful support in diagnosis and follow-up as a widely available, repeatable, non-invasive and safe technique. Although SGUS is not yet included in the dominant primary SS classification, several studies supported its inclusion in the American College of Rheumatology/European League Against Rheumatism criteria. In this context, a novel imaging technique, ultra-high frequency ultrasound (UHFUS), is being explored. Compared to the frequencies used in conventional ultrasound (US) (up to 22 MHz), UHFUS operates with higher frequencies (30-100 MHz) allowing for outstanding image resolution, up to 30 µm. UHFUS permits the scan of both major and minor SGs, opening new avenues for the integration of tissue and imaging biomarkers. Although further studies are needed to confirm its role, this novel imaging technique might lead to several potential improvements, including earlier diagnosis, reduction of unnecessary and inadequate biopsies and better management and follow-up of patients with primary SS.

Discovering a new anatomy: exploration of oral mucosa with ultra-high frequency ultrasound.

OBJECTIVES: Ultra-high frequency ultrasound (UHFUS) is a recently developed diagnostic technique involving the use of ultrasound frequencies up to 70 MHz, allowing to obtain 30 µm resolution of targets located within 1 cm from the surface. Oral mucosa can be affected by diverse pathological conditions, which are currently investigated by means of clinical examination. In this scenario, intraoral UHFUS can provide additional information and support clinical assessment of oral mucosa. In this preliminary study, typical features of normal oral mucosa are described, in order to set a benchmark for the future identification of oral soft tissue alterations. METHODS: Twenty healthy subjects (10 males and 10 females, mean age 30 years) were enrolled and underwent intraoral UHFUS examination. In all the subjects, tongue, buccal mucosa, gingiva, lip mucosa, and palate were scanned, and images acquired. Intraoral UHFUS scan included Brightness-mode and Doppler mode acquisitions performed with a standardized protocol. UHFUS images were postprocessed and analyzed using a dedicated software. UHFUS-based biomarkers (epithelial thickness, echogenicity, and vascularization) were employed for image description. RESULTS: Normal oral anatomy of the different sites analyzed was described. For all the sites, UHFUS biomarkers were characterized, and information on typical aspect of oral mucosa was retrieved. CONCLUSIONS: In this explorative study, we suggest a potential role for intraoral UHFUS in the study of oral mucosa, giving insights into the possibility to improve the assessment, diagnosis, and management of the conditions involving oral mucosa. UHFUS seems a promising tool, which could potentially support clinical examination in daily oral medicine practice.

The efficacy of Ultra-High Frequency Ultrasonography in the diagnosis of intraoral lesions.

OBJECTIVES: The aim of the present study was to evaluate the diagnostic efficacy of ultra-high frequency ultrasound (UHFUS) imaging of intraoral soft tissue lesions. STUDY DESIGN: The study included 160 patients presenting with oral soft tissue lesions classified into 4 categories: autoimmune diseases, mucosal growths, potentially (pre)malignant lesions, and oral cancer. Each lesion was evaluated by means of intraoral UHFUS, through B-mode and C-mode acquisitions of the area of interest. The UHFUS findings were compared with the histopathologic findings. RESULTS: All values for sensitivity, specificity, and negative predictive value exceeded 90%. Sensitivity was perfect (100%) for mucosal growths and oral cancer. Specificity was almost perfect for all 4 categories of lesions, ranging from 97% to 99%. Values for positive predictive value ranged from 83% to 99%. CONCLUSIONS: UHFUS was beneficial in imaging the oral mucosa and the superficial aspects of the underlying soft tissue in detail because of the high spatial resolution of the technique. Consistent patterns were recognized for different categories of lesions. UHFUS holds the promise of being a valuable support to the clinician in terms of diagnosis, treatment, and follow-up of oral lesions.