Magnetic resonance imaging findings of sclerosing microcystic adenocarcinoma: A case report and review of the literature.

Sclerosing microcystic adenocarcinoma (SMA) is a rare malignant tumor of the salivary glands that closely resembles cutaneous microcystic adnexal carcinoma (MAC). It was newly listed in the 5th edition of the WHO classification of head and neck tumors. This report describes the case of a 61-year-old woman who presented with masses on the floor of the mouth. The masses showed low signal intensity on T2-weighted images (T2WI) and with low apparent diffusion coefficient (ADC) values. Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) revealed a plateau or persistence after rapid initial enhancement. Histopathologically, the tumors comprised small infiltrating strands of cells that formed small ducts and cysts embedded in thick fibrous stroma, consistent with SMA. Low signal intensity on T2WI with a low ADC value and a plateau or persistence after rapid initial enhancement on DCE-MRI reflect the fibrous and cellular components of the tumor and can be considered characteristic MRI findings of SMA.

3D printed kidney model could be an important educational tool for residents.

INTRODUCTION: This study aimed to evaluate whether it is useful for junior physicians to use a three-dimensional (3D) kidney model when evaluating the R.E.N.A.L. nephrometry score. MATERIALS AND METHODS: An expert and four urology residents retrospectively evaluated the R.E.N.A.L. nephrometry scores of 64 renal tumors (62 patients) that underwent robot-assisted partial nephrectomy at our hospital. The expert evaluated 64 R.E.N.A.L. nephrometry scores with computed tomography (CT), whereas four residents evaluated 32 cases using CT alone and the other 32 cases using CT and a 3D kidney model. The consistency between the expert and residents was assessed by Cohen's kappa score. Patient-specific 3D kidney models were created in a gird style using a 3D printer based on CT or magnetic resonance imaging of the patient. RESULTS: For all four residents, the accuracy of the overall R.E.N.A.L. nephrometry score was significantly higher with the 3D model and CT than with CT alone (P < .001). Regarding the individual components of the R.E.N.A.L. nephrometry score, the accuracy rates of "E," "N," "A," and "L" scores were higher with the 3D model and CT than with the CT alone (P = .020-.089). CONCLUSION: Patient-specific 3D-printed kidney models could improve the resident's understanding of the renal tumor complexity and could be an important educational tool for residents.

Magnetic Resonance Imaging Findings of Lymphoepithelial Carcinoma of the Submandibular Gland: A Case Report.

Lymphoepithelial carcinoma (LEC) is an uncommon neoplasm strongly associated with Epstein-Barr virus (EBV). LEC of the salivary glands (LECSG) is very rare: the most commonly affected site is the parotid gland, followed by the submandibular gland. This report describes the case of a 58-year-old man who presented with a left submandibular mass that had gradually increased in size over five years. On magnetic resonance imaging (MRI), the mass showed low apparent diffusion coefficient (ADC) values, rapid initial enhancement before reaching a plateau on dynamic contrast-enhanced MRI (DCE-MRI), and internal septal-like enhancement. Histopathologically, the tumor comprised polygonal or round tumor cells with atypical or pleomorphic nuclei and numerous lymphocytes, separated by heavy fibrosis. Immunohistological findings were positive for AE/AE3, CD20, and EBV-encoded small RNA in situ hybridization (EBER-ISH), consistent with LEC. A low ADC value with rapid initial enhancement before reaching a plateau on DCE-MRI was thought to reflect abundant cellular components with tumor neoangiogenesis, whereas internal septal-like enhancement reflects separating heavy fibrosis. To the best of our knowledge, this is the first case report describing ADC value and DCE-MRI findings of LECSG, and these findings can be considered characteristic MRI findings of LECSG.

Ectopic adrenocortical adenoma in the renal hilum mimicking a renal cell carcinoma.

Ectopic adrenocortical tissue can arise along the path of embryonic migration, such as the celiac axis, broad ligament, adnexa of the testis, and spermatic cord. Occasionally, ectopic adrenocortical tissues undergo marked hyperplasia and develop into ectopic adrenocortical adenomas. This report describes the case of a 60-year-old man who was incidentally found to have a lipid-containing mass with early enhancement and delayed washout in the right renal hilum. A renal cell carcinoma was suspected, and robot-assisted partial nephrectomy was performed, but the final diagnosis was an ectopic adrenocortical adenoma. We should include ectopic adrenocortical adenoma in the differential diagnosis when we find a lipid-containing tumor adjacent to the kidney.

Natural history of asymptomatic renal artery pseudoaneurysm after robot-assisted partial nephrectomy.

BACKGROUND: We assessed the natural history of renal artery pseudoaneurysm (RAP) after robot-assisted partial nephrectomy (RAPN). METHODS: From May 2016 to September 2020, 106 patients underwent RAPN for renal tumors at our institution. Among 100 patients, excluding 6 who were ineligible for contrast-enhanced computed tomography (CE-CT), 4 underwent renal artery selective embolization (RAE), of which 2 cases were emergency RAE within 7 days after RAPN and the other 2 were prophylactic RAE 8 or more days after RAPN. In 98 patients examined for the clinical course of asymptomatic RAP managed by surveillance, excluding the 2 who underwent emergency RAE, routine CE-CT was performed at 7 days, 1 month and 3 months after RAPN. Factors influencing the occurrence of RAP among these 98 patients, including the 2 who underwent emergency RAE and excluding the 2 who underwent prophylactic RAE, were analyzed by logistic regression analysis. RESULTS: Median [interquartile range (IOR), range] observation period, age, radiographic tumor size, and maximum diameter of RAP were 20.8 (23.9, 3.0-57.6) months, 63 (18, 22-84) years, 23 (11, 9-48) mm, and 6.6 (5.2, 3.0-16.0) mm, respectively. CE-CT detected 28 RAPs in 23 (23.0%) of 100 patients by 7 days after RAPN and routine CE-CT detected 25 RAPs in 21 (21.4%) of 98 patients excluding 2 who underwent emergency RAE at 7 days after RAPN. RAP was diagnosed by routine CE-CT in 21 (21.4%), 1 (1.0%), and 0 (0%) patients at 7 days, 1 month, and 3 months after RAPN, respectively. In univariate analysis, age [odds ratio (OR) 0.144: 69-84 vs. 22-56 years old, P=0.0179], R.E.N.A.L [radius (tumor size as maximal diameter), exophytic/endophytic properties of tumor, nearness of tumor deepest portion to collecting system or sinus, anterior/posterior descriptor and location relative to polar line] nephrometry score (OR 1.374, P=0.0382), warm ischemic time (OR 1.085, P=0.0393), and renorrhaphy time (OR 1.055, P=0.0408) were significantly associated with the occurrence of RAP. In multivariate analysis, only age (OR 0.124, P=0.0148) was a significant factor. CONCLUSIONS: Asymptomatic RAP up to 15 mm in diameter resolved spontaneously 3 months after RAPN. Young age (under 56 years) may be a factor in the development of RAP.

Combination Laser Treatment With Real-Time Ultrasound Navigation for Oral Venous Malformations.

Vascular lesions, including hemangiomas and vascular malformations, are common benign diseases. More than 50% originate from blood vessels or vascular structures and are locate in the head and neck region. This study aimed to evaluate the efficiency and safety of a combination of laser treatments for oral venous malformations using ultrasound navigation. This study reports 3 cases of massive vascular malformation in the oral cavity, which were treated by a combination of a multiple spotted transmucosal irradiation technique (the so-called leopard technique) for the superficial layer, and intralesional photocoagulation for the deep layer using a neodymium-doped yttrium aluminum garnet laser, under real-time ultrasound navigation. All cases presented with a venous malformation with multiple blue swellings on the dorsum of the tongue, which had a maximum dimension of over 30 mm. The percent reduction in the size of the lesions was determined by magnetic resonance imaging. All cases showed a decrease in lesion volume of over 80%, without extensive tissue necrosis, 6 to 12 months after the laser treatment. None of the patients experienced any complications, and all were satisfied with the treatment outcome after one irradiation session.The results of this study suggest that laser treatment using ultrasound navigation is a promising approach for the safe and minimally invasive resolution of oral vascular lesions without scarring and loss of normal tissue architecture, sensation, oral function.

Thyroglossal Duct Carcinoma Originating in the Hyoid Bone.

Thyroglossal duct (TGD) carcinoma is a rare malignant tumor arising from remnants of thyroid tissue or the wall of the duct and generally occurs along the anatomic course of the TGD. TGD carcinoma originating in the hyoid bone is extremely rare but can occur since the TGD penetrates the hyoid bone on rare occasions. This report describes the case of a 30-year-old man with TGD carcinoma originating in the hyoid bone. Computed tomography demonstrated a mass in the hyoid bone that expanded the cortical bone of the hyoid. The mass had a central solid component with calcification and a marginal cystic component. When we encounter a calcified mass in the hyoid bone, we should consider TGD carcinoma among the differential diagnoses.

A modified preauricular and transmandibular approach for surgical management of osteosarcoma of the mandibular condyle within the masticator space and infratemporal fossa: a case report.

BACKGROUND: Osteosarcomas of the head and neck region are rare entities that comprise < 10% of all osteosarcomas. Multimodality treatment of patients with osteosarcoma is well-established for osteosarcoma in long bones, and the benefits of chemotherapy in long bones are clearly known. However, there is no consensus regarding the effects of chemotherapy in cases of head and neck osteosarcoma. The prognostic factor for head and neck osteosarcoma is complete tumor resection with negative margin, which is a radical surgery. However, a clear margin may be difficult to achieve in the head and neck region. CASE PRESENTATION: We present a case of a 69-year-old Japanese woman who developed osteosarcoma of the condyle within the masticator space and infratemporal fossa, which was treated with radical surgery using a modified preauricular and transmandibular approach. Although we recommended adjuvant treatment after surgery, the patient refused this treatment. There was no evidence of local recurrence or distant metastasis through 30 months of follow-up. CONCLUSIONS: Our modified preauricular and transmandibular approach allowed access to the masticator space and infratemporal fossa, thereby increasing complete resection of the tumor and resulting in minimal functional and cosmetic deficits.

Otosclerosis and Dysplasias of the Temporal Bone.

Many bone dysplasias, some common and others rare, may involve the temporal bone causing conductive, sensorineural, or mixed hearing loss, vestibular dysfunction, or skull base foraminal narrowing, potentially affecting quality of life. Some conditions may affect only the temporal bone, whereas others may be more generalized, involving different regions of the body. High-resolution computed tomography may detect subtle osseous changes that can help define the type of dysplasia, and MR imaging can help define the degree of activity of lesions and potential associated complications.

Using CT texture analysis to differentiate between nasopharyngeal carcinoma and age-matched adenoid controls.

OBJECTIVES: To investigate the use of texture analysis to quantitatively distinguish nasopharyngeal carcinoma (NPC) from normal adenoid on CT. METHODS: In this IRB-approved, retrospective study, nasopharyngeal tissues in 13 patients with NPC and 13 control patients were manually contoured, segmented, and imported to an in-house developed texture analysis program, which extracted 41 texture features. Basic descriptive statistics were performed to evaluate for differences in texture parameters between NPC and controls. RESULTS: Statistically significant differences between NPC and controls were seen in 32 of 41 texture features. These significant differences were present in 11 of 12 histogram features, 4 of 5 gray-level co-occurrence matrix features, 7 of 11 gray-level run length features, 4 of 4 gray-level gradient matrix features, and 6 of 9 Laws features. CONCLUSION: Significant differences in many texture features were seen between NPC and normal adenoids. CT texture analysis may aid in differentiating NPC from normal adenoid tissue.

Craniofacial Manifestations of Systemic Disorders: CT and MR Imaging Findings and Imaging Approach.

Many systemic diseases or conditions can affect the maxillofacial bones; however, they are often overlooked or incidentally found at routine brain or head and neck imaging performed for other reasons. Early identification of some conditions may significantly affect patient care and alter outcomes. Early recognition of nonneoplastic hematologic disorders, such as thalassemia and sickle cell disease, may help initiate earlier treatment and prevent serious complications. The management of neoplastic diseases such as lymphoma, leukemia, or Langerhans cell histiocytosis may be different if diagnosed early, and metastases to the maxillofacial bones may be the first manifestation of an otherwise occult neoplasm. Endocrinologic and metabolic disorders also may manifest with maxillofacial conditions. Earlier recognition of osteoporosis may alter treatment and prevent complications such as insufficiency fractures, and identification of acromegaly may lead to surgical treatment if there is an underlying growth hormone-producing adenoma. Bone dysplasias sometimes are associated with skull base foraminal narrowing and subsequent involvement of the cranial nerves. Inflammatory processes such as rheumatoid arthritis and sarcoidosis may affect the maxillofacial bones, skull base, and temporomandibular joints. Radiologists should be familiar with the maxillofacial computed tomographic and magnetic resonance imaging findings of common systemic disorders because these may be the first manifestations of an otherwise unrevealed systemic process with potential for serious complications. Online supplemental material is available for this article. ©RSNA, 2018.

Imaging of Sjögren Syndrome and Immunoglobulin G4-Related Disease of the Salivary Glands.

The salivary glands are commonly affected in systemic autoimmune disease and diseases of unknown pathogenesis. Sjögren syndrome (SjS) can be affected by other systemic diseases. Immunoglobulin G4-related disease (IgG4-RD) commonly affects salivary glands. Imaging findings are usually nonspecific; however, radiologists should be familiar with the manifestations to avoid diagnostic delay. Findings of early-stage SjS are difficult to identify on routine computed tomography or MR imaging. Chronic SjS can be diagnosed from MR imaging and sialographic findings. Multiglandular and localized involvement of IgG4-RD is difficult to differentiate from malignant lymphoma for multiglandular disease and salivary gland carcinoma for localized disease.

Management of a Brain Abscess Presumably Caused by Radiation Osteomyelitis of the Mandible.

In this clinical report, we present the management of a brain abscess that was presumed to be caused by radiation osteomyelitis of the mandible. The patient underwent chemoradiotherapy for oropharyngeal carcinoma on the left side at the Department of Otolaryngology of our hospital in 2000. Local recurrence or metastasis did not occur post-treatment. In January 2009, the patient was diagnosed with radiation osteomyelitis of the mandible on the left side, complicated by a pathologic fracture. In July 2011, numbness occurred in the left upper extremity and the patient was transferred to the emergency center of our hospital. A computed tomography scan showed a tumor lesion in the brain that was diagnosed as a brain abscess by magnetic resonance imaging. Neurosurgeons performed burr hole drainage of the abscess, followed by administration of antibiotics. Although impaired fine movements of the left hand remain, progress has been relatively favorable with no recurrence of osteomyelitis or brain abscess post-surgery.

Characteristics of dynamic magnetic resonance imaging of idiopathic severe frozen shoulder.

BACKGROUND: The purpose of this study was to evaluate the effectiveness of current techniques for dynamic 3-dimensional magnetic resonance imaging (MRI) in the diagnosis of idiopathic severe frozen shoulder (FS). MATERIALS AND METHODS: Subjects consisted of 5 healthy volunteers and 16 patients with idiopathic severe FS. We defined severe idiopathic FS as follows: range of motion ≤100° in forward flexion, ≤10° in external rotation, and ≤L5 in internal rotation. All patients suffered from continued global range of motion loss for at least 6 months. We evaluated the diagnostic characteristics of 3-dimensional dynamic MRI in FS patients compared with those in healthy volunteers. RESULTS: MRI of all FS patients displayed an abnormal intake of blood flow from the acromial arterial network and the branches of circumflex humeral arteries into the axillary pouch and the rotator interval. We named this finding "burning sign." The burning sign was present at all phases of the condition. In the FS group, the patients with enhanced deposition of contrast medium in the axillary pouch in the delayed phase (n = 11) had a statistically significant score for pain during exercise, higher than that of patients with reduced deposition of contrast medium at the same site (n = 5; P = .027). CONCLUSION: Burning sign is an abnormal finding that appears in dynamic MRI of severe FS. Hence, the burning sign may be associated with pain and inflammation in idiopathic FS.

Difference Between HPV-Positive and HPV-Negative Non-Oropharyngeal Head and Neck Cancer: Texture Analysis Features on CT.

OBJECTIVE: To identify the specific texture parameter that shows significant differences between human papillomavirus (HPV)-positive (HPV) and HPV-negative (HPV) non-oropharyngeal carcinoma (non-OPC) using texture analysis. METHODS: Forty-six patients of non-OPC patients (oral cavity, larynx, and hypopharynx) with known HPV status, who underwent contrast-enhanced computed tomography for initial staging, were retrospectively reviewed. Segmentations of the primary lesion were manually performed, and an in-house developed texture analysis program extracted 42 texture features from each segmented volume. A t test was used to evaluate differences between HPV and HPV non-OPCs (P < 0.05). RESULTS: Sixteen texture parameters, including 5 histogram features (P ≤ 0.03), 3 gray-level co-occurrence matrix features (P ≤ 0.02), 1 gray-level run-length feature (P = 0.009), 2 gray-level gradient matrix features (P ≤ 0.02), and 5 Law features (P ≤ 0.04), showed significant differences. CONCLUSIONS: Texture analysis demonstrated significant differences between HPV and HPV non-OPCs on computed tomography images, which may have a potential to prove morphologic feature differences among HPV-related tumors.

Imaging characteristics of metastatic nodes and outcomes by HPV status in head and neck cancers.

OBJECTIVES/HYPOTHESIS: Although several imaging characteristics of human papillomavirus (HPV)-related head and neck squamous cell carcinoma (HNSCC) have been reported, imaging features of nodal metastasis and influence to outcomes have not been well studied thus far. The purpose of the study was to investigate the imaging characteristics of nodal metastasis by HPV status in HNSCC and to clarify whether those findings influence the outcomes. STUDY DESIGN: Retrospective review. METHODS: Computed tomography and magnetic resonance imaging for initial staging on 139 patients of HNSCC with known HPV status were retrospectively reviewed. We investigated imaging characteristics of the nodal metastasis including the presence of extracapsular spread (ECS), and also investigated the influence of nodal metastasis characteristics to outcomes by HPV status. Two-year actuarial control and survival rates were estimated using the Kaplan-Meier product-limit method (P < 0.05). RESULTS: Eighty-eight patients with nodal metastasis were identified and outcome information was available for 78 patients. Nodal metastasis was significantly more common in HPV-positive patients compared to HPV-negative patients (75% vs. 54%, P = 0.009). HPV-positive patients showed a higher prevalence of ECS compared to HPV-negative patients (77% vs. 56%, P = 0.041). The prevalence of disease recurrence was more common in HPV-negative patients (67% vs. 13%, P < 0.0001), and it was independent of the presence of ECS in nodal metastasis. CONCLUSIONS: Nodal metastases were significantly more common in HPV-positive HNSCC, whereas the prevalence of disease recurrence was greater in HPV-negative HNSCC. Although ECS was noted in the majority of the HPV-positive patients with nodal metastasis, rates of recurrence were lower compared to HPV-negative patients. LEVEL OF EVIDENCE: 4.

Ultrasonic wave properties of human bone marrow in the femur and tibia.

Ultrasonic wave properties of human bone marrow obtained in the femur and tibia were measured using an ultrasound pulse technique. The measured frequency range was 4-10 MHz, and the temperature range was 30 °C-40 °C. The sound velocity was 1410 m/s, and the attenuation coefficient was 4.4 dB/cm at 36 °C (10 MHz). These values decreased with temperature. Site dependence and individual differences in elderly human bone marrow were negligible. The slopes of the attenuation coefficient were estimated by a power law. The values of the exponent n were 2.0 (30 °C-38 °C) and 2.3 (40 °C).

A Melanocytic Lesion Extending From the Right Ear to the Nasopharynx in a Pediatric Patient: A Case Report.

BACKGROUND: Blue nevus is a benign dermal melanocyte tumor that mainly arises from the skin. We report an extremely rare case of blue nevus in a pediatric patient with extensive progression from the middle ear and inner ear to the nasopharynx through the Eustachian tube. CASE REPORT: A 2-year-old girl with blue tympanum was referred to our department. Computed tomography scans and magnetic resonance imaging were performed, followed by a tissue biopsy and histopathologic evaluations. Radiologic examinations revealed that the lesion had progressed beyond the middle ear into the inner ear and the nasopharynx through the Eustachian tube. Subsequent histopathologic examinations indicated dermal dendritic melanocytic proliferations, but no evidence of malignancy. Based on the clinical and histopathologic findings, we concluded that the lesion was consistent with blue nevus. DISCUSSION: Blue nevus is a relatively common skin lesion. However, no prior reports have described the extension of blue nevus from the auditory organ to the nasopharynx in a pediatric patient. Despite the benign nature of the lesion, the patient experienced profound hearing loss in the affected ear, which necessitates continued monitoring as the lesion may expand with patient growth.

Clinical associations of incidentally detected parotid gland calcification on CT.

OBJECTIVES/HYPOTHESIS: Parotid gland calcifications can be incidental findings on computed tomography (CT) and have been reported to be associated with chronic inflammatory conditions. Associations between parotid gland calcification and other common medical conditions have not been reported. METHODS: Following institutional review board approval, 1,571 patients who underwent noncontrast head CT with 1.25-mm slice thickness on a 64-detector row CT between January 2011 and July 2011 were retrospectively reviewed for parotid gland calcifications. Medical records were reviewed for chronic kidney disease, alcoholism, autoimmune conditions, endocrine disorders, elevated alkaline phosphatase, and HIV (human immunodeficiency virus) status. Statistical analyses were performed using Fisher's exact test and multiple logistic regression. RESULTS: Sixty-three of 1,571 (4%) patients had parotid gland calcifications. Significant associations were observed between parotid gland calcifications and HIV infection (P = 0.002), chronic kidney disease (P < 0.0001), alcoholism (P < 0.0001), elevated alkaline phosphatase (P = 0.003), and autoimmune disease (P = 0.02). CONCLUSION: Parotid gland calcifications were associated with HIV, alcoholism, chronic kidney disease, autoimmune disease, and elevated alkaline phosphatase. LEVEL OF EVIDENCE: 4.