The diagnostic accuracy of ultrasonography for soft tissue lipomas: a systematic review

Ultrasound Evaluation of Soft Tissue Masses and Parotid Gland in Clinical Rheumatology

Soft tissue masses are very common and may appear in the context of rheumatic diseases. They usually occur alone but may occasionally be part of the syndromes and can sometimes involve periarticular tissues. Soft tissue masses can be divided into several categories. In this article, we have categorized them into 3 different groups: (1) pseudotumors, (2) benign tumors, and (3) malignant tumors. Parotid enlargement will also be discussed in this study. The majority of Soft tissue masses are pseudotumors or benign tumors, which can be easily characterized with ultrasound, therefore, considered the first screening tool in the study of this type of lesion. If the tumor is deep or poorly accessible, or present with suspected signs of malignancy, the sonographer may suggest expanding the study with magnetic resonance imaging and/or an ultrasound-guided biopsy of the lesion. Ultrasound is also a good technique for the parotid and submandibular glands and is very useful for evaluating and monitoring Sjogren's syndrome.

Atypical lipoma of the right piriformis muscle: a case report and review of the literature

BACKGROUND

Piriformis muscle mass is rare, which is particular for intrapiriformis lipoma. Thus far, only 11 cases of piriformis muscle mass have been reported in the English literature. Herein, we encountered one patient with intrapiriformis lipoma who was initially misdiagnosed.

CASE PRESENTATION

The patient is a 50-year-old Chinese man. He complained of osphyalgia, right buttock pain, and radiating pain from the right buttock to the back of the right leg. Both ultrasound and magnetic resonance imaging demonstrated a cyst-like mass in the right piriformis muscle. Ultrasonography-guided aspiration was performed on this patient first, but failed. He was then recommended to undergo mass resection and neurolysis of sciatic nerve. Surprisingly, final histology revealed the diagnosis of intrapiriformis lipoma. The patient exhibited significant relief of symptoms 3 days post-surgery.

CONCLUSION

Diagnosis and differential diagnosis of radicular pain are potentially challenging but necessary. Atypical lipoma is prone to be misdiagnosed, especially in rare sites. It is notable for clinicians to be aware of the presence of intrapiriformis lipoma to avoid misdiagnosis and inappropriate treatment.

Real-time ultrasound phase imaging

The Correlation-Based (CB) imaging method is characterized by its high spatial resolution capabilities, but it is known to require heavy computational resources due to its high complexity. This paper shows that the CB imaging method can be used to estimate the phase of the complex reflection coefficients contained in the observation window. The resulting Correlation-Based Phase Imaging (CBPI) method can be used to segment and identify different features or tissue elasticity variations in a given medium. A Numerical validation is first proposed by considering a set of fifteen point-like scatterers on a Verasonics Simulator. Then, three experimental datasets are used to show the potential of CBPI on scatterers and specular reflectors. In vitro imaging results are first presented to show that CBPI allows retrieving phase information on hyperechoic reflectors, but also on weak reflectors such as elasticity targets. It is demonstrated that CBPI helps distinguishing regions of different elasticity, but of same low-contrast echogenicity, which is otherwise impossible with standard B-mode or Synthetic Aperture Focusing Techniques (SAFT). Then, CBPI of a needle in an ex vivo chicken breast is performed to show that the method works on specular reflectors. It is shown that the phase of the different interfaces associated to the first wall of the needle are well reconstructed using CBPI. The heterogeneous architecture used to enable real-time CBPI is presented. A Nvidia GeForce RTX 2080 Ti Graphics Processing Unit (GPU) is used to process the real-time acquired signals from a Verasonics Vantage 128 research echograph. Frame rates of 18 frames per second are achieved for the whole acquisition and signal processing chain on standard a 500 × 200 pixels grid.

Fibrolipoma of Flexor Digitorum Profundus Tendon of Ring Finger Causing Triggering and Intermittent Carpal Tunnel Syndrome

Introduction

Lipomas are most common soft-tissue tumors but rarely are found to be symptomatic. <1% of lipomas are found in hand. Subfascial lipomas can cause pressure symptoms. Carpal tunnel syndrome (CTS) can be idiopathic or secondary to any space-occupying lesion. Triggering usually occurs due to inflammation/thickening of A1 pulley. Most have reported a lipoma in distal forearm or near median nerve, leading to triggering of index or middle finger and carpal tunnel symptoms. All the cases reported had either an intramuscular lipoma in flexor digitorum superficialis (FDS) tendon slip of index or middle finger, with or without accessory belly of FDS muscle or a neurofibrolipoma of the median nerve. In our case, the lipoma was under palmer fascia, in flexor digitorum profundus (FDP) tendon sheath of fourth finger causing triggering of the ring finger and CTS symptoms in flexion of the ring finger. Hence, this is a first report of this kind in the literature.

Case Report

We hereby report a one of its kind case in which a 40-year-old Asian male patient had triggering of the ring finger with associated intermittent CTS symptoms, on making a fist, secondary to space-occupying lesion in palm, which was diagnosed by ultrasound as lipoma in FDP tendon of the ring finger in palm. This lipoma was surgically removed by AO ulnar palmer approach and carpal tunnel was decompressed. Histopathology report confirmed the lump to be fibrolipoma. The patient had complete relief of symptoms postoperatively. At 2 years follow-up, there was no recurrence.

Upper extremity mass with lipomatous axillary involvement and multiple level encasement of the brachial plexus

A 40-year-old female presented for surgical consultation of an upper extremity soft tissue mass. Initial ultrasound report recorded a 5.5 cm mass, consistent with a subcutaneous lipoma. Intra-operative visualization revealed an intramuscular lipoma emerging from brachialis muscle. Post-excision MRI was ordered for continued axillary fullness which revealed lipomatous extension into axilla and posterior arm with multiple level encasement of the brachial plexus. Lipomas with brachial plexus involvement are rare and can present with a range of symptoms and distortion of local anatomy. Surgical debulking is challenging requiring microsurgical expertise for adequate removal and to minimize long-term neurological deficits.

Surgical excision of complex lipoma from the foot: A case report

Malignant soft tissue tumors of the foot and ankle are rare but diagnostic imaging and/or interventional biopsy are vital to establish the nature and grading of a suspicious tumor prior to definitive surgical intervention. The purpose of the study is to provide an account on how a symptomatic mass of the plantar aspect of the foot warranted a referral to a sarcoma center, highlighting the importance of having access to diagnostic imaging and a pathway to refer suspected cases to specialist centers. A single patient with a symptomatic soft tissue tumor of the plantar foot was referred from our service to the regional sarcoma center who considered to be benign, and therefore, open surgical resection was performed by our team. Histopathological analysis identified the excised mass as a lipoma. At 2 years, postoperatively there was no recurrence, and the patient presented with an asymptomatic foot. United Kingdom (UK) guidelines suggest that all soft tissue masses of suspicious nature, greater than 50 mm, deep seated irrespective of size, or fast growing lesions should be referred to a sarcoma unit prior to surgical management. European guidance identifies a threshold of 15 mm for a mass in the foot. Patients presenting with red flag symptoms irrespective of size of mass should be referred to a sarcoma center. Advanced imaging and multidisciplinary input to enable appropriate surgical planning is recommended for suspicious soft tissue tumors that present to the foot and ankle surgeon.

Ultrasonography in dermatologic surgery: revealing the unseen for improved surgical planning

Ultrasonography (US) is a modern, in vivo imaging method, which is increasingly being used in dermatology as a complementary tool to clinical examination and dermoscopy. At higher frequencies (15 MHz and above), US is an established method for assessing benign and malignant skin lesions, locoregional staging, monitoring the therapeutic efficacy in various inflammatory skin conditions, and patient follow-up. One field, which may increasingly benefit from performant imaging techniques such as US is dermatologic surgery. Preoperative imaging of cutaneous tumors, inflammatory skin conditions (hidradenitis suppurativa, abscesses, etc.), or nail pathology provide dermatologic surgeons with relevant information for an optimal surgical planning, identifying potential complex aspects which might require interdisciplinary approaches, herein sparing unnecessary surgical interventions and increasing patients' compliance. In this review, we discuss the increasing significance of US in the field of dermatologic surgery, as well as the spectrum of cutaneous pathology where sonography can aid in the preoperative setting to provide a more precise, individualized surgical planning for better counseling to our patients and improved surgical results.

Invaluable role of histopathology in the diagnosis of cutaneous leiomyosarcoma in insulin injection site reaction

Soft tissue sarcomas (STSs) are rare and may often be misdiagnosed, resulting in delays in treatment. A 67-year-old cisgender woman with type 2 diabetes mellitus and obesity presented to her primary care physician with a mass on her left proximal arm. The clinical opinion of the attending physician was that of an insulin injection site reaction. After further evaluation from the physician, the patient was diagnosed with a lipoma without confirmatory histology. The patient continued to present with an enlarging mass, decline in health status and continued with local wound care. The patient underwent a confirmatory biopsy following which, the patient was diagnosed with leiomyosarcoma. This case report highlights the case of a person with a low or moderate income with a self-reported low health literacy living in a rural community and how STS may be misdiagnosed in medically underserved. The patient’s primary or oncology care team are not involved in the production or review of this case report.

The development of musculoskeletal radiology for 100 years as presented in the pages of Acta Radiologica

During the last 100 years, musculoskeletal radiology has developed from bone-only radiography performed by everyone to a dedicated subspecialty, still secure in its origins in radiography but having expanded into all modalities of imaging. Like other subspecialties in radiology, it has become heavily dependent on cross-sectional and functional imaging, and musculoskeletal interventions play an important role in tumor diagnosis and treatment and in joint diseases. All these developments are reflected in the pages in Acta Radiologica, as shown in this review.

A hemangioma in the masseter muscle: a case report

Intramuscular hemangiomas of the masseter muscle are uncommon tumors and therefore can be difficult to accurately diagnose preoperatively, due to the unfamiliar presentation and deep location in the lateral face. A case of intramuscular hemangioma of the masseter muscle in a 66-year-old woman is presented. Doppler ultrasonography showed a 34× 15 mm hypoechoic and hypervascular soft tissue mass in the left masseter muscle, suggesting hemangioma. The mass was excised via a lateral cervical incision near the posterior border of the mandibular ramus. The surgical wound healed well without complications.

Ultra-high-frequency ultrasound of superficial and musculoskeletal structures in the pediatric population

Because of its relatively low cost, lack of ionizing radiation and great versatility, US is considered the imaging modality of choice to evaluate a large variety of pediatric conditions. Imaging of superficial structures and small anatomical parts can be at times limited with standard US. Recent advances in technology yielded ultra-high-frequency US systems that are capable of scanning with frequencies as high as 70 MHz and resolutions of 30 μm. This technology, approved by the United States Food and Drug Administration, has not been widely used in the clinical setting. It has the potential to become a powerful diagnostic tool in clinical practice, especially in the evaluation of infants, given their inherent body habitus. Our main objective is to discuss the use of ultra-high-frequency US at a tertiary care center. This pictorial essay presents a gamut of pediatric pathologies pertaining to imaging of the soft tissues and the superficial and musculoskeletal structures. Our aim in this pictorial essay is to highlight and illustrate the role of ultra-high-frequency US in improving the depiction of common and less common pathologies. We think it also helps to gain a new understanding of the normal anatomy in the pediatric population and to display specific features not shown by standard US and, in certain cases, ones that lead to a change in diagnosis.

Anterior Fontanelle Dermoid Cyst: Surgical Technique

Dermoid cysts are benign congenital lesions that usually appear on the surface of the skull, mainly on the anterior fontanelle. Diagnosis is usually made in the first months of life by physical examination and imaging studies such as CT, MRI, or ultra sound (US) Doppler. It is important to distinguish it from other similar lesions that represent greater surgical complexity, morbidity, and mortality. In this work, we show the principle differential diagnoses, the diagnostic approach, and the surgical technique used in the resection of the dermoid cyst located over the anterior fontanelle.

Rare Forms of Lipomatosis: Dercum's Disease and Roch-Leri Mesosomatous Lipomatosis

In contrast to obesity, which is very frequent, lipomatosis and lipodystrophy syndromes are rare diseases of adipose tissue. Lipodystrophy syndromes are characterized by metabolic abnormalities associated with partial or generalized lipoatrophy. Lipomatosis is defined by the presence of several body lipomas without lipoatrophy. Dercum’s disease (DD) and Roch-Leri mesosomatous lipomatosis (RLML) are rare and poorly characterized forms of lipomatosis. They have raised little clinical interest despite the non-negligible consequences of DD on quality of life. The main clinical presentation of these diseases includes multiple lipomas, which are painful in DD (in contrast to RLML). The two diseases are frequently associated with obesity and metabolic syndrome, with hypertension, diabetes, or dyslipidemia. The long-term course of the diseases remains poorly described. DD affects mainly women, whereas RLML mostly affects men. In both diseases lipomas are found on the back and thighs, as well as on the abdomen in DD and the forearms in RLML. The painful lipomas tend to recur after surgery in DD (in contrast to RLML). Most cases are sporadic. No specific treatment has been identified, as the pathophysiology remains unknown. Nevertheless, low-grade fat inflammation and specific abnormalities such as hyperbasophilia deserve further investigation. The aim of this review is to analyze the available literature on the topic.

Elastofibroma Dorsi: Case Report with Point of Care Ultrasound Primary Care Applications

Elastofibroma dorsi (ED) is an uncommon, benign, slow-growing soft tissue tumor with an unclear etiology. The growth often presents as a local deformity with mild pain or discomfort in the subscapular region of geriatric populations. The following paper discusses a 73 year old female with mildly painful ED who presented to her primary care physician. We further review current literature on epidemiology, utilization of point of care ultrasound (POCUS) and treatment options.

Speech and mastication difficulties following treatment by a "street dentist": A case of oral lipoma

In this report, we present the case of a 68-year-old male patient with a complaint of mastication and speech limitations one year after the prescription of a fixed bridge and the construction of "connected" crowns by a "street dentist." A thorough oral examination revealed a multilobulated swelling in the right buccal mucosa that extended to the buccal sulcus. The lesion, which was first noticed as a small, asymptomatic swelling by the patient one year prior, seemed to have undergone enlargement since the prostheses were prescribed. The lesion was completely removed via surgical excision under general anesthesia. Histopathological examination of the excisional mass revealed mature adipocytes and features consistent with conventional or classic lipoma. This case highlights the importance of receiving dental treatment from a qualified professional, whose responsibilities include performing a thorough examination of the oral cavity during treatment planning and delivery, review appointments, and regular dental visits. Such investigation is important to allow for early disease detection and control, especially for patients with complex treatment needs as well as those who may present with asymptomatic and slow-growing lesions such as lipomas.

A systematic review of symptomatic small bowel lipomas of the jejunum and ileum

Introduction

Small bowel lipomas are rarely encountered benign adipose growths found within the small intestine wall or mesentery. Limited up-to-date evidence exists regarding such lipomas. We aim to aid clinical decision-making and improve patient outcomes through this comprehensive review.

Methodology

The terms 'small bowel,' 'small intestine,' 'jejunum' and 'ileum' were combined with 'lipoma.' EMBASE, Medline and PubMed database searches were performed. All papers published in English from 01/01/2000-31/12/2019 were included. Simple statistical analysis (t-test, Anova) was performed.

Results

142 papers yielded 147 cases (adults = 138, pediatric = 9). Male = 88, female = 59 (average age = 49.9 years). Presenting symptoms: abdominal pain = 68.7%; nausea/vomiting = 35.3%, hematochezia/GI bleeding = 33.3%; anaemia = 10.9%; abdominal distension = 12.2%; constipation = 8.9%; weight loss = 7.5%. Mean preceding symptom length = 58.1 days (symptoms >1 year excluded (n = 9)). Diagnostic imaging utilised: abdominal X-Ray = 33.3%; endoscopy = 46.3%; CT = 78.2%; ultrasound = 23.8%. 124/137 (90.5%) required definitive surgical management (laparotomy = 89, laparoscopcic = 35). 9 patients were successfully managed endoscopically. Lipoma location: ileum = 59.9%, jejunum = 32%, mesentery = 4.8%. Maximal recorded lipoma size ranged 1.2-22 cm.Mean maximum lipoma diameter and management strategy comparison: laparotomy 5.6 cm, laparoscopic = 4.4 cm, endoscopic = 3.7 cm, conservative = 4.5 cm. One-way Anova test, p value = 0.21. Average length of stay (LOS) was 7.4 days (range = 2-30). T-test p value = 0.13 when comparing management modalities and LOS. 4 complications, 0 mortality.

Conclusions

Important previously undocumented points are illustrated; a clearer symptom profile, diagnostic investigations utilised, size and site of lipomas, types and effectiveness of management modalities, associated morbidity and mortality. Open surgery remains the primary management. No statistically significant difference in LOS and lipoma size is demonstrated between management strategies. Endoscopic and laparoscopic techniques may reduce utilising invasive surgery in the future as skillset and availability improve.

Imaging in Primary Sjögren's Syndrome

Primary Sjögren's syndrome (pSS) is a systemic autoimmune disease characterized by dysfunction and lymphocytic infiltration of the salivary and lacrimal glands. Besides the characteristic sicca complaints, pSS patients can present a spectrum of signs and symptoms, which challenges the diagnostic process. Various imaging techniques can be used to assist in the diagnostic work-up and follow-up of pSS patients. Developments in imaging techniques provide new opportunities and perspectives. In this descriptive review, we discuss imaging techniques that are used in pSS with a focus on the salivary glands. The emphasis is on the contribution of these techniques to the diagnosis of pSS, their potential in assessing disease activity and disease progression in pSS, and their contribution to diagnosing and staging of pSS-associated lymphomas. Imaging findings of the salivary glands will be linked to histopathological changes in the salivary glands of pSS patients.

Diagnostic accuracy of an integrated approach using conventional ultrasonography, and Doppler and strain elastography in the evaluation of superficial soft tissue lesions

Purpose

To assess the diagnostic accuracy of an integrated approach using conventional ultrasonography, colour Doppler ultrasonography, and elastography strain ratios in tandem in the evaluation of superficial soft tissue lesions.

Material and methods

Sixty-five subjects were included in this prospective cross-sectional study. Greyscale features and Doppler parameters were recorded. Strain elastography of the non-vascular and non-cystic lesions was performed and strain ratios were calculated. Fine-needle aspiration or biopsy of all the lesions was performed depending on their site and condition. Inter-rater k agreement was used to determine the strength of agreement between imaging-based diagnosis and histopathological diagnosis. A diagnostic test was used to calculate the sensitivity, specificity, positive predictive value, and negative predictive value. A p value of < 0.05 was considered statistically significant.

Results

Multiple superficial soft tissue lesions were studied, the majority of which were lipomas, vascular anomalies, and epidermoid cysts. The diagnostic accuracy was very high and varied from 92.31% to 100% for various masses. The imaging-based diagnosis was in agreement with the histopathological diagnosis in 86.15% (n = 56) and disagreement in 13.85% (n = 9) of the cases (p < 0.007). There was very good inter-rater agreement between the imaging-based diagnosis and histopathological diagnosis (κ = 0.818).

Conclusions

The combined use of conventional ultrasonography, colour Doppler, and elastography strain ratios provides a very effective non-invasive tool for the diagnosis of superficial soft tissue lesions and may negate the need for unnecessary biopsies. The advantage of this integrated approach using various ultrasound techniques needs no further emphasis.

Accuracy of ultrasound in the characterization of superficial soft tissue tumors: a prospective study

OBJECTIVE

To prospectively evaluate the accuracy of ultrasound in defining the specific nature of superficial soft tissue masses as well as determining malignancy.

MATERIALS AND METHOD

Eight hundred twenty-three superficial soft tissue masses were prospectively evaluated with ultrasound by one of five experienced musculoskeletal radiologists. The radiologist at the time of examination provided one to three specific differential diagnoses and the perceived level of confidence with regard to each diagnosis. Clinical and ultrasound diagnoses were compared with the histological diagnosis to determine accuracy. Tumor malignancy was determined by histology or clinical/imaging follow-up.

RESULTS

Histological correlation was present for 219 (26.6%) of the 823 masses. Compared with histology, the accuracy of clinical and ultrasound examination for determining specific tumor type was 25.6% and 81.2% respectively considering all differential diagnoses provided. Radiologists were "fully confident" with the ultrasound diagnosis in 585 (71.1%) of 823 masses overall. In this setting, when compared with histology, the diagnostic accuracy of ultrasound was 95.5%. When the radiologist was "not fully confident," accuracy was 41.3% for the first differential diagnosis and 60.9% for all differential diagnoses. Diagnostic accuracy improved with increasing radiologist experience. Sensitivity, specificity, positive predictive value, and negative predictive value of ultrasound for identifying malignant tumor were 93.3%, 97.9%, 45.2%, and 99.9% respectively.

CONCLUSIONS

One can be "fully confident" at characterizing over two-thirds of superficial soft tissue masses based on ultrasound appearances and, in this setting, diagnostic accuracy is very high. Ultrasound examination is also highly accurate at discriminating benign from malignant superficial soft tissue masses.

Ossifying Lipoma in Costal Arches That Suggest Extensive Pulmonary Involvement: Case Report

Background:

Lipomas are the most common benign soft tissue tumors in the general population. These lesions can appear on any part of the body and usually develop in the subcutaneous superficial tissue. Lipomas that show ossifying changes are very rare, representing less than 1% of the reported lipomas. They usually manifest as hard nodular lesions in the head and neck, the extremities, the sternoclavicular region, and the subcutaneous tissue in general; they are rare in the costal arches.

Case presentation:

We report the case of a patient with a history of multiple diseases and 2 tumor-like lesions with internal lytic areas detected in the fourth right costal arch and in the eighth left costal arc; we describe his clinical manifestations, radiological and laboratory findings as well as the pathological results and outcome.

Conclusions:

Ossifying lipomas are rare benign tumors with asymptomatic clinical presentation. It is important to perform an adequate radiological differentiation from other more aggressive lesions such as liposarcomas.