Heterogeneous High Signal Intensity Research Articles

Fibro-adipose vascular anomaly (FAVA) - diagnosis, staging and management

BackgroundThe diagnosis and treatment of fibro-adipose vascular anomaly (FAVA) of the limb remains challenging since this entity is rare and complex. This paper is aimed to describe the clinical and imaging features, staging and management of this underrecognized disease of the limb.Material and methodPatients diagnosed with FAVA and managed between September 2019 and May 2022 in department of pediatric surgery & vascular anomalies of Xi’an international medical center hospital were retrospectively reviewed. Data extracted include age at presentation, previous diagnosis, affected muscles, symptoms, previous treatment, our management, and follow-up.ResultsThirty-two patients with FAVA were diagnosed and managed in our center. There was a female sex predominance, with 23 female (72%) and 9 male (28%) in the cohort. Only one lesion was noticed during infancy; the remaining presented at age 1 to 20 years (median, 7 years). The most commonly involved muscles were gastrocnemius (14/32, 44%) and soleus (13/32, 40%). Swelling (mass), pain and contractures were the most common presentations. MRI featured a heterogeneous and ill-defined intramuscular high signal intensity. Diseases were staged according to clinical features: stage I (pain stage, n = 4), stage II (contracture stage, n = 20) and stage III (deformity stage, n = 8). Patients with stage I disease underwent radical resection and obtained a cure. Patients with stage II disease received radical resection and possible Achilles lengthening, having an outcome of cure. Personalized treatment was required in patients with stage III disease, including radical/partial/staged resection, Achilles lengthening/tenotomy, joint capsulotomy, neurolysis/neurectomy, tendon transfer, stretching exercises, and oral sirolimus/alpelisib. Significant improvement of symptoms was achieved in most.ConclusionThe most distinct features of FAVA include enlarging mass, severe pain and contracture. Based on distinct clinical and radiologic features, it is not difficult to make the diagnosis of FAVA. Earlier awareness of this disease can reduce misdiagnoses. Surgery-based comprehensive management can typically improve pain and contracture. Oral sirolimus or alpelisib plays an important role in treatment of unresectable lesions and major nerve involvement. Surgery alone can be curative in early stage FAVA.

The dynamic contrast enhanced-magnetic resonance imaging and diffusion-weighted imaging features of alveolar soft part sarcoma.

Alveolar soft part sarcoma (ASPS) is a rare type of soft tissue sarcoma that predominantly affects adolescents and young adults. Early diagnosis of ASPS is crucial for optimal therapeutic planning and improving prognosis, but its diagnostic features are not well delineated. This study aimed to retrospectively analyze the imaging features of ASPS with an emphasis on the dynamic contrast-enhanced-magnetic resonance imaging (DCE-MRI) and diffusion-weighted imaging (DWI) findings to identify imaging findings that might suggest the diagnosis to radiologists. The imaging features of 34 patients with pathologically proven limb ASPS were retrospectively analyzed. A total of 23 underwent DCE-MRI, and 12 underwent DWI. Among the 34 cases of ASPS, 31 tumors were in the lower extremities, and 3 were in the upper extremities. The maximum tumor diameters ranged from 3.0 to 19.4 cm (mean, 8.7±3.96 cm). A total of 28 cases had well-defined borders. The masses demonstrated heterogeneous high signal intensity on T2-weighted imaging (T2WI) and the fat-suppressed (FS) T2WI sequence and slight hyperintensity on T1-weighted imaging (T1WI). A total of 25 lesions had thin hypointense bands on T1WI and T2WI. Intra- and peri-tumoral tubular areas of flow void were exhibited on both T1WI and T2WI in all cases. A total of 12 cases showed a high signal on DWI, and the mean apparent diffusion coefficient (ADC) value was (0.86±0.07)×10-3 mm2/s [range, (0.6-1.4)×10-3 mm2/s]. Persistent remarkable enhancement of the lesion was displayed on contrast-enhanced scans. The time-intensity curves (TICs) of 23 masses showed early arterial enhancement and slow washout of contrast. ASPS most commonly presents in the lower extremities of adolescents or young adults. Hyperintense T1WI, T2WI, and DWI signals, low ADC, flow voids, early arterial enhancement are frequent MRI features.

An imaging‑based diagnostic approach to vascular anomalies of the oral and maxillofacial region.

The accurate diagnosis of vascular anomalies (VAs) is considered a challenging endeavor. Misdiagnosis of VAs can lead clinicians in the wrong direction, such as the performance of an unnecessary biopsy or inappropriate surgical procedures, which can potentially lead to unforeseen consequences and increase the risk of patient injury. The purpose of the present study was to develop an approach for the diagnosis of VAs of the oral and maxillofacial region based on computed tomography (CT), magnetic resonance imaging (MRI) and dynamic contrast-enhanced MRI (DCE-MRI). In the present study, the CT and MR images of 87 VAs were examined, and the following imaging features were evaluated: Detectability of the lesion, the periphery of the lesion, the inner nature of the lesion, the density of the lesion on CT, the signal intensity of the lesion on MRI, the detectability of phleboliths and the shape of the lesion. A total of 29 lesions were further evaluated using the contrast index (CI) curves created from the DCE-MRI images. A diagnostic diagram, which is based on the imaging features of VAs and CI curve patterns, was subsequently extrapolated. The results obtained demonstrated that the VAs were detected more readily by MRI compared with CT, whereas the detectability of phleboliths was superior when using CT compared with MRI. VAs showed a propensity for homogeneous isodensity on CT, whereas, by contrast, they exhibited a propensity for heterogeneous hyperdensity on CE-CT. VAs also showed a propensity for homogeneous intermediate signal intensity when performing T1-weighted imaging (T1WI), heterogeneous high signal intensity when performing short tau inversion recovery MRI, and heterogeneous high signal intensity when performing fat-saturated CE-T1WI. The CI curves of VAs were found to exhibit a specific pattern: Of the 29 CI curves, 23 (79.3%) showed early weak enhancement, followed by a plateau leading up to 400-600 sec. An imaging-based diagnostic diagram was ultimately formulated. This diagram can act as an aid for radiologists when they are expecting to find a VA, and hopefully serve the purpose of simplifying the diagnostic process. Taken together, the findings of the present study indicated that DCE-MRI may be considered a useful tool for the diagnosis of VAs.

Clear Cell Sarcoma of Soft Tissue: A Case Report

Introduction: Clear cell sarcoma (CCS), is an extremely rare type of sarcoma, frequently diagnosed in young adults, typically arises in the extremities of the limbs and has a predilection for occurring in the tendons and aponeuroses. In the past CCS was called malignant melanoma of the soft parts because the tumor shares clinical, histological and immunohistochemical similarities with amelanotic melanoma, but it is a unique lesion, distinct from melanoma. Case Report: A 33-year old woman with no significant history was referred with an unpainful bulky ulcerated tumor of the right ankle, appeared 05 years prior to presentation following a minimal trauma. The CT of the ankle revealed a bulky mass of the medial surface locally infiltrative associated to nodules of the surrounding adipose tissues and a unilamellar periosteal reaction without bone lysis or osteocondensation. MRI of the ankle showing a lobulated mass arising in the deep structures in iso-intense signal relative to adjacent muscle on T1 and heterogeneous high-signal intensity on T2 infiltrating surrounding adipose tissues without infiltration of muscles. Histological examination showed dermo-hypodermic malignant tumor proliferation. Round cells were arranged in nests separated by dense collagenous septa, with an abundant eosinophilic to clear cytoplasm. The immunohistochemical supplement were positive for Melan-A and HMB-45. Cytokeratin, Vimentin, Desmin and CD99 were negative. The extension assessment made of a head-chest-abdominal-pelvic CT scan showed multiple homolateral inguinal lymphadenopathies necrotic. No other metastasis was detected. The anatomo-clinical confrontation allowed to retain the diagnosis of CCS. Discussion: The tumor occurs most often in adolescents and young adults and was slightly more common in female than in male patients, CCS typically arises in the extremities of the limbs, its occurrence in the upper limbs is less common, described as a slowly growing mass painless. ..........

Angiolipoma of the chest wall: a case report

BackgroundAngiolipoma is a rare histological variant of lipoma. Angiolipoma commonly occurs in the subcutaneous tissues of the extremity and trunk. There are few reports of angiolipoma occurring in the chest wall.Case presentationA 78-year-old woman was referred to our hospital for evaluation of angina pectoris. Coronary computed tomography (CT) showed a soft tissue nodule in the left chest wall by chance. Enhanced chest CT showed a heterogeneous enhanced nodule in the left chest wall. On magnetic resonance imaging (MRI), the lesion showed low signal intensity on T1-weighted images, heterogeneous high signal intensity on T2-weighted images and high signal intensity on fat-suppressed T2-weighted images. The lesion showed heterogeneous enhanced effect on gadolinium-based contrast agent. These radiological findings suggested neurogenic tumor with abundant blood flow or hemangioma. Video-assisted thoracic surgery (VATS) was performed for both diagnostic and therapeutic purposes. Histopathological examination of the tumor showed mature adipose tissue and capillary hyperplasia containing fibrin thrombi. These appearances were consistent with angiolipoma. She had an uneventful recovery and did not show recurrence until 8 months post-surgery.ConclusionsAngiolipoma of the chest wall is extremely rare. Preoperative diagnosis is very difficult because the imaging findings of angiolipoma vary depending on the amount of vascular component and fat component, so surgical resection is suggested to be both diagnostic and therapeutic.

Clinical and imaging characteristics of patients with primary cardiac angiosarcoma

Objective: To investigate the clinical, cardiac imaging characteristics and prognosis of patients with primary cardiac angiosarcoma. Methods: The clinical data of 14 patients hospitalized with primary cardiac angiosarcoma from January 2001 to December 2017 in Peking Union Medical College Hospital were collected and analyzed. Metastatic cardiac angiosarcoma was not included in this study. Patients were followed up post discharge per telephone call or clinical visit. Results: Of the 14 patients, 8 were males and 6 were females, average age was 48 years. The main clinical symptoms were shortness of breath (8/14), hemoptysis (6/14), fever (5/14), chest pain (4/14) and cough (3/14). Imaging examinations showed that the tumors of 8 patients were located in the right heart and 6 in the pericardial cavity. Tumors in the right heart often infiltrate the atrial wall and cause pericardial effusion (7/8). Tumors in the pericardium were characterized by recurrent bloody pericardial effusion (6/6), prone to progressive constrictive pericarditis (3/6), pericardial fluid cytology was often negative (6/6). MRI showed heterogeneous high signal intensity (cauliflower aspect) on T2-weighted image and heterogeneous enhancement with a"sunray" aspect at the perfusion study. At the time of diagnosis, 8 patients developed lung or adrenal metastasis (8/14). The median survival was only 305 days. Conclusions: Primary cardiac angiosarcoma is a rare disease with non-specific clinical manifestation and poor prognosis. Imaging examinations may help diagnosis. The high invasiveness and the easy-to-metastasis feature of the tumor contribute to the poor prognosis of cardiac angiosarcoma.

Imaging Features of Aggressive Giant Cell Tumors of the Mobile Spine: Retrospective Analysis of 101 Patients From Single Center.

Study Design:Retrospective study.Objectives:Giant cell tumors (GCTs) of the mobile spine can be locally aggressive. This study described and classified the typical and atypical appearance of aggressive spinal GCTs according to imaging findings to help the imaging diagnosis, especially for patients with rapid neurological deficit that may require emergent surgery without biopsy.Methods:Computed tomography (CT) and magnetic resonance imaging (MRI) scans of patients diagnosed with aggressive spinal GCTs at single center were reviewed.Results:Overall, 101 patients with 100 CT images and 94 MR images were examined. All lesions were osteolytic with cortical destruction; 95 lesions showed epidural extension; 90 were centered in the vertebral body; 82 showed pathological fracture and/or collapse of the vertebral body; 78 had pseudotrabeculation on CT; 80 showed low-to-iso signal intensity or heterogeneous high-signal intensity with cystic areas on the T2-weighted images; 9 showed fluid–fluid level on T2-weighted images; and 61 patients showed marked enhancement on contrast-enhanced CT and/or MRI. Forty-one lesions (40.6%) had at least 1 atypical radiographic feature: 19 involved ≥2 segments; 11 were centered in the posterior neural arch; 10 had a paravertebral mass over 2 segments; 16 showed partial margin sclerosis with partial cortical destruction on CT scans; and 3 showed mineralization within the tumor on CT. Eighty-eight patients underwent CT-guided biopsy with a diagnostic accuracy rate of 94.3%.Conclusions:Spinal GCTs might appear more radiologically atypical, and about 40% of the lesions may have at least 1 atypical feature. CT-guided biopsies are recommended for definitive diagnosis.

A Giant Enchondroma Mimicking Sarcoidosis: Report of Case and Review of the Literature

Sarcoidosis of the humerus is exceptionally rare and only a few cases have been reported. In this mini-review, a case of enchondroma in proximal humerus mimicking sarcoidosis and the features of bone involvement of sarcoidosis were reviewed. A 41-year-old female who was diagnosed with sarcoidosis in 2009 had used corticosteroids for 4 months. She had not any symptoms until 2014. She was admitted the clinic with a 2-month-history of erythema nodosum on her legs and right shoulder pain. Values of laboratory tests were all within normal limits except erythrocyte sedimentation rate and C-reactive protein levels. The mass in the proximal metaphyseal humerus has the characteristic as a medullary lesion which had calcifications in CT sections. MR images that the mass had low signal intensity on T1-weighted images and heterogeneous high signal intensity on T2-weighted images. It had irregular nodular contrast and the mass did not cause the expansion of the bone. Increased activity was observed on scintigraphy. We suspected the mass which was realized incidentally in a patient with sarcoidosis, could be bone sarcoidosis. As a result of our biopsy, it was enchondroma. Bone neoplasms should be kept in mind in issues like our case report.

Glomangiopericytoma of the Spinal Cord

Glomangiopericytoma, also referred to as a hemangiopericytoma-like tumor or sinonasal type hemangiopericytoma, is a rare tumor of the nasal cavity and paranasal sinus that has never been reported in the spinal cord. Here, we report a case of a 47-year-old man who developed glomangiopericytoma in the thoracic spine. This lesion showed a heterogeneous high signal intensity compared to the spinal cord on a T2-weighted image and an easily enhanced isointense signal on a T1-weighted image.

Intra-articular angiofibroma of soft tissue of the knee: A case report.

Angiofibroma of soft tissue (AFST) is an extremely rare soft tissue neoplasm that typically presents as a slow-growing, painless mass in the extremities. The present study reports an unusual case of an intra-articular AFST occurring in the left knee of a 23-year-old female. Physical examination revealed a 3-cm, relatively mobile, elastic-hard, non-tender mass. Magnetic resonance imaging detected an intra-articular soft tissue mass with iso-signal intensity relative to skeletal muscle on T1-weighted sequences and heterogeneous high signal intensity on T2-weighted sequences. Contrast-enhanced fat-suppressed T1-weighted sequences demonstrated strong peripheral enhancement of the mass. An arthroscopic excision of the mass was performed. Histologically, the tumor was composed of spindle- or oval-shaped cells in a fibromyxoid stroma with a prominent vascular pattern. Immunohistochemically, the tumor cells were diffusely positive for vimentin and CD163 and focally positive for CD68, desmin and estrogen receptor. Based on these findings, the tumor was diagnosed as an AFST. The patient had no evidence of local recurrence within 9 months of follow-up. To the best of our knowledge, this is the first case of intra-articular AFST managed successfully with arthroscopic excision.

Cranial Nerve Schwannomas: Diagnostic Imaging Approach.

Schwannomas are benign nerve sheath tumors that may arise along the complex course of the cranial nerves (CNs), anywhere in the head and neck. Sound knowledge of the CN anatomy and imaging features of schwannomas is paramount for making the correct diagnosis. In this article, we review approaches to diagnosing CN schwannomas by describing their imaging characteristics and the associated clinical presentations. Relevant anatomic considerations are highlighted by using illustrative examples and key differential diagnoses categorized according to regions, which include the anterior skull base, orbit, cavernous sinus, basal cisterns, and neck. The clinical presentations associated with CN schwannomas vary and range from no symptoms to symptoms caused by mass effect or CN deficits. Individuals with the inherited disorder neurofibromatosis type 2 are predisposed to multiple schwannomas. When a lesion follows the course of a CN, the radiologist's roles are to confirm the imaging features of schwannoma and exclude appropriate differential considerations. The characteristic imaging features of CN schwannomas reflect their slow growth as benign neoplasms and include circumscribed margins, displacement of local structures, and smooth expansion of osseous foramina. These neoplasms exhibit various degrees of solid enhancement, often with internal cystic spaces on magnetic resonance (MR) and computed tomographic (CT) images and heterogeneous high signal intensity specifically on T2-weighted MR images. Clinical and/or imaging evidence of end-organ compromise of the involved CN may exist and aid in the identification of the nerve of origin. With a detailed understanding of the course of the CNs, the diagnostic features of CN schwannomas, and the correlation between these data and the associated clinical presentations of these tumors, the radiologist can have a key role in the diagnosis of CN schwannomas and the treatment planning for affected patients. (©)RSNA, 2016.

Magnetic resonance imaging and computed tomography features of alveolar soft-part sarcoma in the right deltoid muscle: A case report.

Alveolar soft-part sarcoma (ASPS) is a rare, highly vascular malignant soft-tissue tumor that predominantly affects young adults. The tumor can occur in any bodily region, but is most frequently observed in the lower deep soft tissues of the extremities, and is rarely observed in the upper extremities. The present study reported a case of ASPS of the right deltoid muscle. The patient presented with a 3-year history of a mass on the right shoulder that exhibited rapid growth in the month prior to diagnosis. Computed tomography (CT) and magnetic resonance imaging (MRI) were performed. The lesion mainly demonstrated isointense or mildly hyperintense signals compared with the muscle on the T1-weighted images of the MRI, and heterogeneous high signal intensity on the T2-weighted images. CT enhancement showed a homogeneous enhanced mass. The tumor was resected and submitted for histopathological examination. The diagnosis was verified as ASPS by microscopic examination and immunohistochemical analysis. No distant metastases were noted. No evidence of local tumor recurrence was seen at 6 weeks following the wide surgical excision. The CT scan revealed no metastatic nodules in either lung during the follow-up. ASPS should be considered as a possible diagnosis when a slow-growing, large mass is detected in young adults in the soft tissue of the extremities, with high signal intensity and numerous signal voids on T1-weighted images (T1WI) and T2WI, and strong contrast-enhancement.

Typical CT and MRI signs of hepatic epithelioid hemangioendothelioma.

To investigate the typical magnetic resonance imaging (MRI) and computed tomography (CT) features of hepatic epithelioid hemangioendothelioma (HEH), the CT and MRI findings of 14 histopathologically confirmed cases of HEH were retrospectively analyzed. Non-contrast and dynamic contrast-enhanced scans were conducted in all cases. A total of 229 lesions were detected in the 14 cases. All cases were classified as one of three types: (i) Solitary nodular type (1 case, 7%); (ii) multifocal nodular type (11 cases, 79%); or (iii) diffuse type (2 cases, 14%). The diameter of the lesions ranged from 5 to 105 mm. For the first two types (solitary and multifocal nodular types), the CT findings included low density lesions with clear margins on non-contrast scans, centripetal enhancement in arterial phase, and homogeneous enhancement in the portal venous and delay phases. The findings of non-contrast MRI scans for these two types included low signal intensity on T1-weighted images, heterogeneous high signal intensity on T2-weighted images, and heterogeneous high signal intensity on diffusion-weighted images. The lesions were predominantly located in submarginal areas. On contrast-enhanced MRI, the findings for the first two types included peripheral ring-like enhancement with a central low signal intensity (‘black target-like’ sign) and a central enhanced core surrounded by a low signal intensity halo (‘white target-like’ sign). The findings for the third HEH type (diffuse type) on CT and MRI scans included low density or heterogeneous signal intensity lesions involving regions of part or the whole liver, coalescent lesions (‘strip-like’ sign), and gradual enhancement along central vessels (‘lollipop’ sign). Collectively, these findings indicate that the ‘white target-like’ sign, ‘black target-like’ sign, ‘lollipop’ sign and ‘strip-like’ sign, in addition to capsular contraction and submarginal location, on CT and MRI imaging may have implications for the diagnosis of HEH. Furthermore, a variety of MRI sequences may provide additional information for the differential diagnosis of HEH.

Successful enucleation of large multinodular/plexiform schwannoma of the foot and ankle.

BackgroundIt is often challenging to completely resect multinodular/plexiform schwannomas involving important deep nerves using minimally invasive surgically techniques.Case descriptionA 32-year-old woman presented with a 5-year history of a slowly growing, painful mass in the medial aspect of the right ankle. Magnetic resonance imaging (MRI) demonstrated multiple nodular lesions with iso-signal intensity relative to skeletal muscle on T1-weighted sequences and heterogeneous high signal intensity on T2-weighted sequences. Mild to moderate enhancement was identified after gadolinium administration. All 58 tumors were completely enucleated using an intracapsular technique. Histological examination confirmed the diagnosis of schwannoma consisting mainly of Antoni A areas. The burning sensation was relieved immediately after surgery. The patient had no aggravated neurological deficit and was very satisfied with the outcome of the treatment at final follow-up.Discussion and evaluationWe experienced a very rare case of a large multinodular/plexiform schwannoma arising from the posterior tibial nerve and its larger terminal branch. Our case had the characteristic MRI features of this condition. It is extremely important to differentiate multinodular/plexiform schwannoma from plexiform neurofibroma and malignant peripheral nerve sheath tumor, with complete surgical enucleation being curative.ConclusionsMRI is a clinically useful modality in the evaluation and detection of deep-seated multinodular/plexiform schwannoma. Intracapsular enucleation seems to be an acceptable treatment for this peculiar tumor located in the foot and ankle.

A case of ganglioglioma extended to the lateral ventricle and associated with neurofibromatosis type 1

We encountered a rare case of intraventricular ganglioglioma associated with neurofibromatosis type 1. A 42-year-old woman presented with a feeling of heaviness of the head and dizziness. She was diagnosed with neurofibromatosis type 1 because she had multiple subcutaneous neurofibromas and café au lait spots. On admission, she deteriorated slightly(Japan Coma Scale 1)and suffered from cognitive dysfunction and right hemiparesis. A computed tomography(CT)scan showed that she had an obstructed hydrocephalus with a long and circular mass lesion, 2cm in diameter, in the anterior horn of the left lateral ventricle. The mass showed low signal intensity(SI)on the T1-weighted image(WI), heterogeneous high SI on the T2-WI, and dense enhancement on a Gd-DTPA contrast MRI, extending from the head of the left caudate nucleus to the lateral ventricle. The patient underwent an urgent operation via an anterior transcallosal approach because of an obstructed hydrocephalus. The tumor was removed in its entirety, including its origin at the caudate head. The pathological diagnosis was a ganglioglioma grade 1 according with the classification of the World Health Organization. Here we describe this case and discuss the rare association between gangliogliomas and neurofibromatosis type 1.

Repaired supraspinatus tendons in clinically improving patients: early postoperative findings and interval changes on MRI.

ObjectiveTo demonstrate and further determine the incidences of repaired supraspinatus tendons on early postoperative magnetic resonance imaging (MRI) findings in clinically improving patients and to evaluate interval changes on follow-up MRIs.Materials and MethodsFifty patients, who showed symptomatic and functional improvements after supraspinatus tendon repair surgery and who underwent postoperative MRI twice with a time interval, were included. The first and the second postoperative MRIs were obtained a mean of 4.4 and 11.5 months after surgery, respectively. The signal intensity (SI) patterns of the repaired tendon on T2-weighted images from the first MRI were classified into three types of heterogeneous high SI with fluid-like bright high foci (type I), heterogeneous high SI without fluid-like bright high foci (type II), and heterogeneous or homogeneous low SI (type III). Interval changes in the SI pattern, tendon thickness, and rotator cuff interval thickness between the two postoperative MRIs were evaluated.ResultsThe SI patterns on the first MRI were type I or II in 45 tendons (90%) and type III in five (10%). SI decreased significantly on the second MRI (p < 0.050). The mean thickness of repaired tendons and rotator cuff intervals also decreased significantly (p < 0.050).ConclusionRepaired supraspinatus tendons exhibited high SI in 90% of clinically improving patients on MRI performed during the early postsurgical period. The increased SI and thickness of the repaired tendon decreased on the later MRI, suggesting a gradual healing process rather than a retear.

Calcifying aponeurotic fibroma of the finger in an elderly patient: CT and MRI findings with pathologic correlation.

Calcifying aponeurotic fibroma (CAF) is a rare, locally aggressive fibroblastic lesion that occurs predominantly in the distal extremities of children and adolescents. In the present study, a case of pathologically proven CAF arising in the right little finger of a 69-year-old woman is presented. Physical examination revealed a firm, immobile, non-tender mass. Plain radiographs showed a faintly calcified soft tissue mass without bone involvement and computed tomography scans clearly demonstrated the presence of the lesion. Magnetic resonance imaging revealed that the lesion exhibited low to intermediate signal intensity on T1-weighted images and heterogeneous high signal intensity with small foci of low signal intensity on T2-weighted spectral presaturation with inversion recovery images. Contrast-enhanced fat-suppressed T1-weighted images demonstrated intense heterogeneous enhancement throughout the mass. The patient underwent an excisional biopsy. Histologically, the tumor showed a biphasic pattern, composed of a moderately cellular fibromatosis-like component and irregular calcified areas with polygonal epithelioid cells. There has been no evidence of local recurrence four months following surgery. To the best of our knowledge, this case report describes the oldest patient with this condition.

Magnetic resonance imaging features of alveolar soft part sarcoma: report of 14 cases

BackgroundThe purpose of this study was to assess the magnetic resonance imaging findings of alveolar soft part sarcoma.MethodsMagnetic resonance images of pathologically proven alveolar soft part sarcoma in 14 patients were retrospectively reviewed, including lesion location, size and shape, border definition, signals on T1-weighted and T2-weighted images, presence or absence of peritumoral and intratumoral flow voids, and enhancement pattern.ResultsPatients included five women and nine men, ranging in age from 27 to 54 years, with a mean age of 36 years. A slow-growing mass without pain was the chief complaint. Eight patients had pulmonary metastases at presentation. Ten lesions arose from the extremities, two were located in the gluteal regions, one affected the presacral space and one occurred in the back. The mean maximal size of the lesions was 9.8 cm, ranging from 6.2 to 16 cm. All lesions appeared as a round (n = 2), ovoid (n = 8) or irregular (n = 4) shape with ill-defined margins. The lesions mainly demonstrated isointense or mildly hyperintense compared to muscle on T1-weighted images, and heterogeneous high signal intensity on T2-weighted images. Peritumoral edemas were observed in six patients. Ten lesions showed intense inhomogeneous enhancement after contrast. Intra- and peritumoral tubular flow voids representing tortuous dilated vessels with rapid blood flow were present in all cases.ConclusionsAlveolar soft part sarcoma has some distinctive magnetic resonance imaging features including a slow-growing, large mass in the soft tissue of the extremities in young adults, with numerous signal voids on T1-weighted and T2-weighted images, and strong enhancement after contrast.

Case 195: Chondrosarcoma of the Posterior Mediastinum

Although chondrosarcoma is rare in the spine, it should be considered when there is a ring and arc appearance of calcifications within adjacent bone and heterogeneous high T2 signal intensity within a paraspinal mass.

Non-Traumatic Myositis Ossificans in the Lumbosacral Paravertebral Muscle

Myositis ossificans (MO) is a benign condition of non-neoplastic heterotopic bone formation in the muscle or soft tissue. Trauma plays a role in the development of MO, thus, non-traumatic MO is very rare. Although MO may occur anywhere in the body, it is rarely seen in the lumbosacral paravertebral muscle (PVM). Herein, we report a case of non-traumatic MO in the lumbosacral PVM. A 42-year-old man with no history of trauma was referred to our hospital for pain in the low back, left buttock, and left thigh. On physical examination, a slightly tender, hard, and fixed mass was palpated in the left lumbosacral PVM. Computed tomography showed a calcified mass within the left lumbosacral PVM. Magnetic resonance imaging (MRI) showed heterogeneous high signal intensity in T1- and T2-weighted image, and no enhancement of the mass was found in the postcontrast T1-weighted MRI. The lack of typical imaging features required an open biopsy, and MO was confirmed. MO should be considered in the differential diagnosis when the imaging findings show a mass involving PVM. When it is difficult to distinguish MO from soft tissue or bone malignancy by radiology, it is necessary to perform a biopsy to confirm the diagnosis.