The First Korean Siblings With Adult-Onset 4H Leukodystrophy Related to Nonsynonymous POLR3B Mutations.

Objectives: 4H leukodystrophy is a rare autosomal recessive hypomyelinating disorder characterized by several combinations of motor dysfunction, abnormal dentition, and ophthalmic and endocrine abnormalities. To date, only a single Korean case report of pediatric leukodystrophy caused by the POLR1C sequence variation has been published, while there are no reports on the POLR3B, POLR3A, or POLR3K variants. Methods: Genetic tests of Korean sibling pairs with primary amenorrhea due to normosmic isolated hypogonadotropic hypogonadism and cognitive or behavioral symptoms were performed by whole-exome sequencing (WES). The WES results were validated by direct Sanger sequencing. Results: We identified biallelic variations in the POLR3B gene of p.Tyr685* and p.Tyr746Cys, which have not been associated with 4H leukodystrophy. Both sequence variants lie in the hybrid-binding domain of the protein RPC2. The protein structure analysis predicted that cysteine substitution of the phylogenetically conserved amino acid tyrosine can cause destabilization. Discussion: The siblings reported are the first POLR3B-related hypomyelinating leukodystrophy cases in Korea. Our report expands the mutational spectrum of 4H leukodystrophy and suggests that it is mandatory to consider its diagnostic possibility in adult patients presenting with primary amenorrhea and mild cognitive or behavioral symptoms.

Clinical Efficacy of Reduced-Dose Gadobutrol Versus Standard-Dose Gadoterate for Contrast-Enhanced MRI of the CNS: An International Multicenter Prospective Crossover Trial (LEADER-75).

BACKGROUND. Gadobutrol and gadoterate are widely used macrocyclic gadolinium-based contrast agents. Given gadobutrol's higher T1 relaxivity, a reduced gadobutrol dose should achieve essentially equivalent diagnostic efficacy as a standard dose of gadoterate. OBJECTIVE. The purpose of our study was to show efficacy of a 25% reduced dose of gadobutrol is noninferior to 100% standard dose of gadoterate for contrast-enhanced MRI of the CNS. METHODS. In this international prospective multicenter open-label crossover trial (LEADER-75 [Lower Administered Dose With Higher Relaxivity: Gadovist vs Dotarem]), adult patients with known or suspected CNS pathology underwent contrast-enhanced brain MRI with standard-dose gadoterate (0.1 mmol/kg); if an enhancing lesion was identified, a second MRI with reduced-dose gadobutrol (0.075 mmol/kg) was performed within 15 days of the first MRI. Three radiologists independently reviewed images to score three primary efficacy measures: subjective lesion enhancement, lesion border delineation, lesion internal morphology. A noninferiority analysis used readers' mean scores of the primary efficacy measures. Noninferiority of reduced-dose gadobutrol to standard-dose gadoterate for primary efficacy measures was defined as the difference in score between reduced-dose gadobutrol images and unenhanced images achieving at least 80% of the difference in score between standard-dose gadoterate images and unenhanced images. A post hoc analysis was performed to directly compare contrast-enhanced images for equivalence. Secondary efficacy variables included the number of lesions detected, reader confidence, diagnostic performance for malignancy, and reader preference in side-by-side comparison. RESULTS. The efficacy analysis included 141 patients (78 men, 63 women; mean age, 58.5 ± 13.5 [SD] years). Improvement of reduced-dose gadobutrol over unenhanced images was noninferior to improvement of standard-dose gadoterate over unenhanced images using a 20% noninferiority margin for all three primary efficacy measures using mean readings (p ≤ .025). In the post hoc analysis, the mean reading for the three primary efficacy measures differed by less than 1% between reduced-dose gadobutrol and standard-dose gadoterate, supporting equivalence of all measures using a narrow ± 5% margin (p ≤ .025). The total number of lesions detected by mean reading was 301 for reduced-dose gadobutrol versus 291 for standard-dose gadoterate. Mean reader confidence was 3.3 ± 0.6 for reduced-dose gadobutrol versus 3.3 ± 0.6 for standard-dose gadoterate. Sensitivity (58.7%), specificity (91.8%), and accuracy (70.2%) for malignancy from majority reading were identical for reduced-dose gadobutrol and standard-dose gadoterate. Reader preference was not different (95% CI, -0.10 to 0.11). CONCLUSION. A 25% reduced dose of gadobutrol is noninferior to standard-dose gadoterate for contrast-enhanced brain MRI. CLINICAL IMPACT. Use of reduced-dose gadobutrol should be considered for brain MRI, particularly in patients undergoing multiple contrast-enhanced examinations. TRIAL REGISTRATION. ClinicalTrials.gov NCT03602339; EU Clinical Trials Register EudraCT 2018-00690-78.

Pituitary Blastoma in a 19-Year-Old Woman: A Case Report and Review of Literature.

BACKGROUND: Pituitary blastoma is a malignant neoplasm of the pituitary gland that was recognized by the World Health Organization in 2017. It is commonly diagnosed in children before 24 months of age. Here, we report the first case of a young adult patient who was diagnosed with pituitary blastoma with increased levels of growth hormone instead of adrenocorticotropic hormone and provide a review of the literature. CASE DESCRIPTION: A 19-year-old woman presented to our hospital with visual disturbance. She had a medical history of Wilms' tumor and multinodular goiter. The brain imaging showed a 3.2 × 2.5 × 1.8-cm solid sellar and suprasellar cystic mass that upwardly displaced the optic chiasm. She had an elevated level of growth hormone but a normal level of adrenocorticotropic hormone, cortisol, and prolactin. The mass was subtotally removed through the left pterional craniotomy. The pathologic examination suggested a pituitary blastoma. Thereafter, the patient was treated with chemotherapy and radiotherapy. At 4-year follow-up postsurgery, her overall well-being is good. CONCLUSIONS: Although in this case the patient was a young adult, pituitary blastoma should be taken into consideration when children have an enhanced sellar and suprasellar mass with peripherally located cysts.

MR imaging findings of metastatic hepatocellular carcinoma in the nasal cavity: a rare site of spread.

We here report an extremely rare case of metastatic hepatocellular carcinoma to the nasal cavity only with MRI scan including diffusion-weighted imaging and a brief review of previous literature case reports.

Pure Intrasellar Meningioma Mimicking Pituitary Macroadenoma: Magnetic Resonance Imaging and Review of the Literature.

Intrasellar meningioma originating from the sellar floor is extremely rare and is often indistinguishable from pituitary macroadenoma, both clinically and radiologically. Here, we report a case involving a 68-year-old patient with intrasellar meningioma possibly originating from the sellar floor and present a brief review of all previous cases reported in the English literature.

Salivary duct carcinomas: clinical and CT and MR imaging features in 20 patients.

INTRODUCTION: Salivary duct carcinoma (SDC) is an uncommon high grade adenocarcinoma of the salivary gland with a grave prognosis. The aim of this study was to investigate the clinical and CT and MR imaging features of SDC. METHODS: We retrospectively evaluated the clinical and CT and MR imaging findings in 20 patients (14 men and six women; mean age, 59 years) with histologically proved SDC. We also tried to correlate clinicoradiological tumor staging with pathologic tumor staging in 17 patients who underwent surgery. RESULTS: The tumor originated in the parotid gland (n = 11; 55%), the submandibular gland (n = 7; 35%) and the buccal space along the distal Stensen's duct (n = 2; 10%). Locoregional recurrence occurred in 41% and distant metastasis in 47%. Fifty-eight percent died of the disease with a mean survival period of 32 months after diagnosis. On CT and MR images, SDC was mostly seen as an ill-defined (85%) and infiltrative (60%) mass with frequent calcification (50%) and necrosis (80%). Although various signal intensities were seen on MR images, six of nine tumors contained the areas of marked hypointensity on T2-weighted images. Clinicoradiological tumor staging correlated well with pathologic tumor staging in 82% of the patients. CONCLUSION: Ill-defined, infiltrative mass with calcification on CT scans and the areas of marked hypointensity on T2-weighted MR images may be useful radiologic features to suggest the diagnosis of SDC. CT and MR imaging are useful for staging of SDC.

Ultrasonographic analysis of subcutaneous angiolipoma.

OBJECTIVE: To describe and analyze the ultrasonographic appearance of subcutaneous angiolipoma in pathology-proven cases. MATERIALS AND METHODS: We retrospectively searched the January 2004 to May 2011 surgical pathology database for cases of pathology-proven angiolipoma. The ultrasonographic findings were analyzed for angiolipoma size, shape, margin, echo texture, echogenicity, acoustic enhancement, calcifications, and color Doppler flow. RESULTS: Of 31 angiolipomas, 19 lesions occurred in an upper extremity, one in a lower extremity, nine in the chest and abdominal wall, and two in the back. The mean tumor size was 17.7 mm. Twenty-five cases (80%) appeared as oval mass and all tumors had well-defined margins. All cases showed hyperechoic; 14 (45%), homogeneous; 17 (55%), heterogeneous. Seven cases (23%) showed blood flow in the mass. Acoustic enhancement and calcification was not shown in any cases. A correct preoperative diagnosis was made in three cases (10%) by ultrasonography. CONCLUSIONS: Most subcutaneous angiolipomas are oval-shaped, have well-defined margins, and hyperechoic appearance on ultrasonography. Although color Doppler flow of subcutaneous angiolipoma is not seen in many cases, it may helpful in differentiating angiolipoma from ordinary subcutaneous lipoma.

Imaging findings of head and neck inflammatory pseudotumor.

OBJECTIVE: The purpose of this article is to describe imaging features of head and neck inflammatory pseudotumor in the brain, orbit, sinonasal cavity, temporal bone or skull base, and other rare locations. CONCLUSION: Although the radiologic differentiation from malignancy is not clearly possible, we suggest that familiarity with the manifestations of inflammatory pseudotumor can help avoid unnecessary radical surgery before histopathologic proof of malignancy.

A spectrum of neuroradiological findings in children with haemophagocytic lymphohistiocytosis.

BACKGROUND: Haemophagocytic lymphohistiocytosis (HLH) is a rare multisystem disorder. CNS involvement is a frequent and poor prognostic component. Better neuroradiological surveillance may be beneficial for patient management and outcome. OBJECTIVE: To describe various neuroradiological findings in nine patients with HLH with an emphasis on correlation with disease activity and treatment response. MATERIALS AND METHODS: Between 1996 and 2007, nine children with HLH with CNS involvement were identified in a single centre. Neuroradiological findings from CT, MRI, and proton MR spectroscopy, and the clinical records of the nine children were retrospectively reviewed. The frequency, distribution, characteristics of abnormal neuroradiological findings and changes during follow-up were correlated with clinical findings. RESULTS: Initial abnormal findings included multiple nodular or ring-enhancing parenchymal lesions, a laminated pattern of nodular parenchymal lesions on T2-weighted images, leptomeningeal enhancement, confluent parenchymal lesions, mild ventriculomegaly, and diffuse brain oedema. On follow-up imaging studies, haemorrhagic transformation and atrophy were seen where brain parenchymal lesions had been previously. These abnormal neuroradiological findings showed good correlation with clinical findings. Proton MR spectroscopy also demonstrated typical changes of metabolites during the course of the disease. CONCLUSION: A spectrum of neuroradiological findings in children with HLH is well matched with the clinical course of the disease and, therefore, a comprehensive analysis of the findings is useful to monitor disease activity and treatment responses.

Agenesis of bilateral internal carotid arteries and posterior fossa abnormality in a patient with facial capillary hemangioma: presumed incomplete phenotypic expression of PHACE syndrome.

PHACE syndrome is a neurocutaneous syndrome with the following features: posterior fossa malformations of the brain, large facial hemangiomas, arterial anomalies, cardiac anomalies and aortic coarctation, and eye abnormalities. We report a rare case of bilateral internal carotid artery agenesis with transcranial collaterals from the external carotid arteries and agenesis of the vertebrobasilar system in a possible PHACE syndrome. We suggest that the patient had an incomplete phenotypic expression of the PHACE syndrome. Although the phenotypic spectrum is broad and is still largely unexplored, the extent of the cephalic neural crest cells insulted genetically or by other causes at a certain time during the development of the embryo might explain the variable phenotypic expression of PHACE syndrome.

Alveolar soft-part sarcoma of the head and neck: clinical and imaging features in five cases.

BACKGROUND AND PURPOSE: Alveolar soft-part sarcoma (ASPS) of the head and neck is an extremely rare malignancy. Although the clinical and imaging features of this tumor have been reported, a periodic review of unusual tumors is useful. The purpose of this study was to describe the clinical and imaging features of ASPS of the head and neck. METHODS: Between January 1990 and May 2004 at our institution, five head and neck ASPS were diagnosed in five patients (two male and three female patients; age range, 4-22 years). Clinical and imaging findings were reviewed retrospectively. Imaging studies consisted of contrast material-enhanced CT (in four patients), MR imaging (in four patients), and digital subtraction angiography (in two patients). RESULTS: The locations of the tumor were tongue in two cases, larynx in one case, buccal space in one case, and paravertebral space in one case. This tumor appeared as a large lobulating-contoured mass with high signal intensity and flow voids on T2-weighted images and showed strong enhancement on contrast-enhanced CT and MR images. Preoperative angiography showed high vascularity. Wide surgical excisions were performed in four cases. Mean follow-up periods were 16 months (range, 6-30 months), and no recurrence was noted except for the laryngeal case. CONCLUSION: ASPS should be included in the differential diagnosis of head and neck tumor when a slow-growing, large mass with high signal intensity and flow voids on T2-weighted images and strong enhancement on contrast-enhanced CT or MR image is seen, particularly in young female patients.

Preoperative portal vein embolization with a new liquid embolic agent.

PURPOSE: To evaluate the effectiveness and safety of a new liquid embolic agent in preoperative portal vein embolization. MATERIALS AND METHODS: Embol-78 was obtained by means of hydrolysis of polyvinyl acetate and was dissolved in a mixture of ethanol and nonionic water-soluble contrast medium. After percutaneous puncture of the portal vein, embolization of the right portal vein was performed in 22 patients with hepatocellular carcinoma and in 29 patients with nonhepatocellular carcinoma. In each group, changes in volume of the future liver remnant, portal venous pressure, and liver enzymes were evaluated both before and after embolization. Complications were also evaluated. RESULTS: Portal vein embolization was successful in all patients, without major complications. The mean volumes of the future liver remnant before and 2 weeks after embolization were 385 mL +/- 138 and 533 mL +/- 140, respectively, in the hepatocellular carcinoma group and 517 mL +/- 348 and 755 mL +/- 197, respectively, in the nonhepatocellular carcinoma group. There were only transient elevations in liver enzyme levels after embolization. Mean portal venous pressures before and after the procedure were 16.7 mm Hg +/- 3.8 and 20.3 mm Hg +/- 3.6, respectively, in the hepatocellular carcinoma group and 11.7 mm Hg +/- 3.5 and 14.6 mm Hg +/- 3.6, respectively, in the nonhepatocellular carcinoma group. In each group, changes in volume of the future liver remnant and portal venous pressure were statistically significant (P <.001). CONCLUSION: The liquid embolic material Embol-78 seems to be effective and safe for preoperative portal vein embolization.