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.

Feasibility and Safety of Mild Therapeutic Hypothermia in Poor-Grade Subarachnoid Hemorrhage: Prospective Pilot Study.

Therapeutic hypothermia (TH) improves the neurological outcome in patients after cardiac arrest and neonatal hypoxic brain injury. We studied the safety and feasibility of mild TH in patients with poor-grade subarachnoid hemorrhage (SAH) after successful treatment. Patients were allocated randomly to either the TH group (34.5°C) or control group after successful clipping or coil embolization. Eleven patients received TH for 48 hours followed by 48 hours of slow rewarming. Vasospasm, delayed cerebral ischemia (DCI), functional outcome, mortality, and safety profiles were compared between groups. We enrolled 22 patients with poor-grade SAH (Hunt & Hess Scale 4, 5 and modified Fisher Scale 3, 4). In the TH group, 10 of 11 (90.9%) patients had a core body temperature of < 36°C for > 95% of the 48-hour treatment period. Fewer patients in the TH than control group (n = 11, each) had symptomatic vasospasms (18.1% vs. 36.4%, respectively) and DCI (36.3% vs. 45.6%, respectively), but these differences were not statistically significant. At 3 months, 54.5% of the TH group had a good-to-moderate functional outcome (0-3 on the modified Rankin Scale [mRS]) compared with 9.0% in the control group (P = 0.089). Mortality at 1 month was 36.3% in the control group compared with 0.0% in the TH group (P = 0.090). Mild TH is feasible and can be safely used in patients with poor-grade SAH. Additionally, it may reduce the risk of vasospasm and DCI, improving the functional outcomes and reducing mortality. A larger randomized controlled trial is warranted.

Functional and anatomical alterations in bilateral vestibulopathy: A multimodal neuroimaging study and clinical correlation.

Object: To study multimodal neuroimaging study including resting state functional MRI (rs-fMRI), anatomical connectivity and brain morphology in patients with bilateral vestibulopathy (BVP) and relationship with clinical correlation. Methods: Thirteen patients with BVP (7 women; mean age ± SD = 63.5 ± 14.7 years, 22-80 years) and eighteen age and gender-matched controls were compared rs-fMRI and anatomical MRI. Also, we analyzed the relationship between multimodal neuroimaging and Dizziness Handicap Inventory score (DHI), Vestibular Disorders Activities of Daily Living Scale (VDRL), Geriatric Depression Scale (GDS) and Hospital Anxiety and Depression Scale (HADS). Results: Compared with controls, BVP patients showed decreased functional connectivity among the key nodes of the salience network, auditory (including vestibular) network, bilateral posterior parahippocampal gyri, bilateral paracingulate gyri, and right frontoparietal network, and the anatomical connectivity in the right cerebellum, corpus callosum tapetum, and left fornix. BVP patients showed decreased gray matter volume in the bilateral parahippocampal gyri, right precentral gyrus, anterior cingulate gyrus, and right middle temporal gyrus and increased gray matter volume in the right superior frontal gyrus compared with controls. Correlation analyses showed rs-fMRI and clinical variables showed no significant result. DHI correlated negatively with anatomical connectivity in the bilateral frontal parahippocampal cingulum, corpus callosum, right inferior fronto-occipital fasciculus, bilateral fornix, and gray matter volumes in the bilateral middle occipital gyri, right superior occipital gyrus, left angular gyrus, and right cuneus in BVP. VADL correlated negatively with Anatomical connectivity in the corpus callosum, bilateral fornix, bilateral cerebellum, bilateral superior and anterior thalamic radiation, right inferior fronto-occipital fasciculus, bilateral fronto-parietal cingulum, right dentatoruburothalamic tract and gray matter volumes in the right angular gyri, bilateral parahippocampal gyri, right middle temporal gyrus, right cuneus, bilateral inferior occipital gyri, left middle occipital gyrus, right superior frontal gyrus, left fusiform gyrus, bilateral caudate, left cerebellar crus, and bilateral calcarine gyri in BVP. Conclusions: This study identified reductions in the volume of the hippocampus and alterations in functional and anatomical connectivity that concurs with previously established characteristics of BVP. The degree of disability can be inferred from the change in the connectivity and volume between vestibular cortical areas and their network.

Incidence, characteristics, and neuroanatomical substrates of vestibular symptoms in supratentorial stroke.

The incidence and characteristics of acute vestibular symptoms, responsible structures, and lateralization of the causative lesions in supratentorial stroke remain unknown. This study aimed to determine the incidence, clinical features, and anatomical correlation of acute vestibular symptoms in supratentorial stroke. We performed a prospective, multicenter, observational study that had recruited patients with supratentorial stroke from the neurology clinics of referral-based four university hospitals in Korea. All patients received a constructed neuro-otological evaluations, and neuroimaging. We analyzed the incidence of acute vestibular symptoms, abnormal ocular motor and vestibular function tests, and stroke lesions. Of 1301 patients with supratentorial stroke, 48 (3.7%) presented with acute vestibular symptoms, and 13 of them (1%) had the vestibular symptoms in isolation. In patients with acute vestibular symptoms, abnormal findings included spontaneous nystagmus (5%), impaired horizontal smooth pursuit (41%), and abnormal tilt of the subjective visual vertical (SVV) (20%). Video head impulse and caloric tests were normal in all the patients. There was no clear correlation between acute vestibular symptoms and involvement of specific vestibular cortex. In patients with unilateral stroke, there was also no lateralization of the causative lesions of acute vestibular symptoms (left vs. right; 52 vs. 48%), even in patients with vertigo (left vs. right; 58 vs. 42%). This study demonstrates that the incidence of acute vestibular symptoms in supratentorial stroke is 3.7%, with being isolated in 1%. The widespread lesions responsible for acute vestibular symptoms implicate diffuse multisensory cortical-subcortical networks in the cerebral hemispheres without a lateralization.

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.

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.

Intra-arterial adjuvant tirofiban after unsuccessful intra-arterial thrombolysis of acute ischemic stroke: preliminary experience in 16 patients.

INTRODUCTION: Intra-arterial (IA) thrombolysis with plasminogen activator is well-known, but the use of IA tirofiban as an adjuvant for IA thrombolysis is not well-known. We investigated the feasibility of IA tirofiban as an adjuvant after unsuccessful IA recanalization with urokinase (UK) for acute ischemic stroke. METHODS: We retrospectively analyzed all 16 consecutive patients (11 men and five women; mean age, 61.3 years; range, 36-85 years) who were treated with IA tirofiban after isolated IA thrombolysis with UK or bridging therapy with systemic recombinant tissue plasminogen activator (rt-PA; 0.6 mg/Kg) and IA UK for acute ischemic stroke. Outcome measures included angiographic recanalization (thrombolysis in cerebral infarction, TICI), symptomatic and asymptomatic intracerebral hemorrhage (ICH), mortality, and functional independence at 3 months (modified Rankin Scale, 0-2). RESULTS: Among the 16 patients treated with IA tirofiban as an adjuvant, 10 patients had conventional dose (<25 ug/kg, bolus) and six patients had high dose (≥25 ug/kg, bolus) of IA tirofiban after unsuccessful IA thrombolysis whether systemic rt-PA used or not. Successful angiographic recanalization (TICI grade 2b or 3) was achieved in 13 patients (13/16) and a functional independence at 3 months in eight patients (8/16). Three months after therapy, three patients had died. There were two patients of symptomatic ICH and four asymptomatic ICH. CONCLUSION: Conventional dose of IA tirofiban as an adjuvant during IA thrombolysis for acute ischemic stroke seems feasible. However, further dose escalation studies should be performed regarding the IA use of tirofiban for acute ischemic stroke.

Classification of persistent primitive trigeminal artery (PPTA): a reconsideration based on MRA.

BACKGROUND: Persistent primitive trigeminal artery (PPTA) is the most common permanent carotid-basilar anastomosis. Magnetic resonance angiography (MRA) has become the primary non-invasive imaging technique for evaluation of cerebral vascular anatomy and can provide detailed 3D imaging of intracranial vessels. PURPOSE: To evaluate the usefulness of MRA for the detection of PPTA and to re-classify its variations based on the embryologic types of PcomA and its relationship with the basilar artery and its branches. MATERIAL AND METHODS: Of the total 7329 patients who underwent MRA at our institution from March 2008 through November 2010, we retrospectively analyzed the MRAs of 24 patients with a PPTA. Special attention was given to defining the relationship of the PPTA and the basilar artery with PcomA and to determine the site of origin, size, and course of the PPTA. The PPTA classification included five types based on their anatomic relationship to the neighboring arteries. Clinical features and associated vascular anomalies are also described. RESULTS: Twenty-four (17 women and seven men, 34 ~ 81 years of age, mean age 59.67 years) of the 7329 patients had a PPTA (0.33 %). Eleven cases (45.8%) were classified as type 1, three (12.5%) as type 2, five (20.8%) as type 3, one (4.2%) as type 4, and four (16.7%) as type 5b. Fifteen PPTAs (62.5%) were located on the left side and nine were located (37.5%) on the right side. The basilar artery proximal to the insertion of the PPTA showed severe to moderate hypoplasia in 13 cases (54%). Nine intracranial artery aneurysms were detected in seven (29%) of the 24 study patients. CONCLUSION: This study revealed five types of PPTA and necessitates an adjustment of the previous classification of PPTA on the basis of our MRA examinations. A PPTA should be considered by both the clinician and the radiologist who interpret MR angiography.

A case of atypical skull base osteomyelitis with septic pulmonary embolism.

Skull base osteomyelitis (SBO) is difficult to diagnose when a patient presents with multiple cranial nerve palsies but no obvious infectious focus. There is no report about SBO with septic pulmonary embolism. A 51-yr-old man presented to our hospital with headache, hoarseness, dysphagia, frequent choking, fever, cough, and sputum production. He was diagnosed of having masked mastoiditis complicated by SBO with multiple cranial nerve palsies, sigmoid sinus thrombosis, and septic pulmonary embolism. We successfully treated him with antibiotics and anticoagulants alone, with no surgical intervention. His neurologic deficits were completely recovered. Decrease of pulmonary nodules and thrombus in the sinus was evident on the follow-up imaging one month later. In selected cases of intracranial complications of SBO and septic pulmonary embolism, secondary to mastoiditis with early response to antibiotic therapy, conservative treatment may be considered and surgical intervention may be withheld.

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.

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.

Perfusion CT of the brain using 40-mm-wide detector and toggling table technique for initial imaging of acute stroke.

OBJECTIVE: Limited coverage of the brain in the z-axis has been a drawback of perfusion CT. The purpose of this study was to evaluate the usefulness of perfusion CT with extended coverage in the z-axis for the assessment of acute stroke in an emergent clinical setting. MATERIALS AND METHODS: Fifty-eight patients who underwent 80-mm-coverage perfusion CT within 24 hours after stroke onset were included. Perfusion CT was performed using a 64-MDCT unit equipped with 40-mm-wide detector and the toggling table technique. Lesion detection by perfusion CT was analyzed using follow-up diffusion-weighted imaging and MR angiography as the reference standards. More conventional 20-mm-coverage perfusion CT was simulated by extracting data obtained at the basal ganglia level for comparison with 80-mm-coverage perfusion CT. RESULTS: Fifty-one patients had acute infarctions and seven patients did not. For 80-mm-coverage perfusion CT, perfusion abnormality was detected in 42 of 51 patients (sensitivity, 82.4%; and specificity, 85.7%). When patients with small artery disease (small acute infarctions in the basal ganglia, thalamus, corona radiata, and pons) were excluded, sensitivity increased to 92.3%. As compared with 80-mm-coverage perfusion CT, 20-mm-coverage perfusion CT missed nine acute infarctions located above or below the level of the basal ganglia (p = 0.0039). CONCLUSION: Perfusion CT with 80-mm-coverage was found to be useful as an initial imaging method in acute ischemic stroke, although it had low sensitivity for detecting small acute infarctions. In particular, this technique provided higher lesion detection than 20-mm-coverage perfusion CT.

18F-FP-CIT dopamine transporter PET findings in cirrhotic patients with parkinsonism.

We report the clinical features and imaging findings of presynaptic dopamine transporter (DAT) positron emission tomography (PET) in four of patients with liver cirrhosis and concurrent parkinsonism. We also reviewed previously reported cases of cirrhosis-related parkinsonism using dopaminergic molecular imaging. Our results using 18F-radiolabeled N-(3-fluoropropyl)-2ß-carboxymethoxy-3ß-(4-iodophenyl) nortropane (FP-CIT) DAT PET in four patients with cirrhosis and parkinsonism showed two different molecular imaging patterns well related to their neurological symptoms. 18F-FP-CIT PET imaging of two patients showed normal DAT density in the striatum. Their clinical features included symmetric parkinsonism, early gait disturbances and postural instability, and the absence of resting tremor. The other two patients showed reduced striatal DAT uptake asymmetrically with a rostrocaudal gradient similar to idiopathic Parkinson's disease (IPD). They had clinical findings of hemiparkinsonism, resting tremor, without early gait disturbance or postural instability. They also showed sustained response to levodopa treatment. Based on the structured review of 21 cases with cirrhosis-related parkinsonism in the literature including the present cases, we categorized cirrhotic parkinsonism into three groups. Eleven of the twenty-one cases were categorized into group 1; levodopa-resistant atypical parkinsonism without a dopaminergic deficit in molecular imaging similar to primary manganism. Another 6 cases were categorized into group 2; coincidental IPD with superimposed cirrhosis with sustained good response to levodopa and presynaptic dopaminergic deficit with rostrocaudal gradient typical of IPD. The other undetermined 4 cases were categorized into group 3. They showed symmetric parkinsonism with variable response to levodopa therapy. Their molecular imaging showed a global diffuse dopaminergic deficit in the presynaptic molecular imaging distinct to group 1 (normal uptake) or 2 (asymmetric rostrocaudal deficit). In conclusion, cirrhosis-related parkinsonism is a heterogeneous disorder.

Neurodevelopmental outcomes in newborns with neonatal seizures caused by rotavirus-associated leukoencephalopathy.

PURPOSE: Rotavirus infection has recently been reported to be associated with seizures accompanied by leukoencephalopathy in newborns. We aimed to determine long-term outcomes and prognostic factors in newborns with neonatal seizures caused by rotavirus-associated leukoencephalopathy. METHODS: We retrospectively reviewed the records and brain magnetic resonance (MR) images of 32 patients who fulfilled the following criteria: (1) neonatal seizures, (2) distinctive symmetric cerebral white matter lesions on diffusion-weighted MR images (DWI), (3) rotavirus infection, (4) absence of a specific etiology of seizures, except for the aforementioned DWI lesions, and (5) Korean Bayley Scales of Infant Development II (K-BSID-II) assessment after 12 months of age. RESULTS: The mean age at seizure onset was 4.7 ±â€¯0.8 days. The median age of the patients at the time of K-BSID-II assessment was 22 months. Fourteen patients (43.8%) showed normal or accelerated performance in the mental and motor scales, while 18 patients (56.2%) had delayed performance in the mental and/or motor scales. Seven patients (21.9%) had significantly delayed performances on the mental and/or motor scales. The percentage of volume of diffusion-restricted lesions based on total brain volume was significantly negatively correlated with the mental developmental index (MDI) score (r = -0.507, p = .003), but not with the psychomotor developmental index (PDI) score (r = -0.324, p = .071). CONCLUSIONS: Rotavirus-associated leukoencephalopathy in newborns around 5 days of age can cause adverse neurodevelopmental outcomes with a wide range of severity. The extent of white matter lesion on initial DWI can predict neurocognitive outcome.

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.

Magnetic resonance imaging of leukoencephalopathy in amnestic workers exposed to organotin.

We report the clinical and neuroimaging findings of 4 men who worked in the production of inorganic metal tin ingot from organotin scrap who presented with similar episodes of reversible amnesia. T2-weighted-fluid-attenuated inversion recovery magnetic resonance imaging (FLAIR MRI) scans in 3 of the patients showed symmetric hyperintensity in the frontoparietal periventricular white matter and the corpus callosum, and reduced apparent diffusion coefficients (ADCs) based on diffusion weighted imaging (DWI). One patient had symmetric faint hyperintensity in the parietal periventricular white matter only in the FLAIR images. The patients had elevated urinary levels of dimethyltin (DMT) and trimethyltin (TMT), but these concentrations decreased following cessation of exposure. Triethyltin, however, was not detected in urine. We diagnosed the present cases with organotin intoxication based on 5 lines of evidence. First, all patients were workers in the same tin-processing industry, complained of similar clinical symptoms, and had similar neuroimaging results. Second, the clinical features are compatible with a diagnosis of organotin encephalopathy. Third, all 4 workers were exposed to organotin for several days, and had high urinary concentrations of DMT and TMT. Fourth, the clinical features and brain MRI results ruled out other cerebral diseases. Fifth, MRI findings support a diagnosis of organotin encephalopathy.

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.