Nonlesional Sources of Contrast Enhancement on Postgadolinium "Black-Blood" 3D T1-SPACE Images in Patients with Multiple Sclerosis.

BACKGROUND AND PURPOSE: We hypothesized that 3D T1-TSE "black-blood" images may carry an increased risk of contrast-enhancing lesion misdiagnosis in patients with MS because of the misinterpretation of intraparenchymal vein enhancement. Thus, the occurrence of true-positive and false-positive findings was compared between standard MPRAGE and volumetric interpolated brain examination techniques. MATERIALS AND METHODS: Sampling perfection with application-optimized contrasts by using different flip-angle evolution (SPACE) images obtained from 232 patients with MS, clinically isolated syndrome, or radiologically isolated syndrome were compared with standard MPRAGE and volumetric interpolated brain examination images. The intraparenchymal vein contrast-to-noise ratio was estimated at the level of the thalami. Contrast-enhancing lesions were blindly detected by 2 expert readers and 1 beginner reader. True- and false-positives were determined by senior readers' consensus. True-positive and false-positive frequency differences and patient-level diagnosis probability were tested with the McNemar test and OR. The contrast-to-noise ratio and morphology were compared using the Mann-Whitney U and χ2 tests. RESULTS: The intraparenchymal vein contrast-to-noise ratio was higher in SPACE than in MPRAGE and volumetric interpolated brain examination images (P < .001, both). There were 66 true-positives and 74 false-positives overall. SPACE detected more true-positive and false-positive results (P range < .001-.07) but did not increase the patient's true-positive likelihood (OR = 1 1.29, P = .478-1). However, the false-positive likelihood was increased (OR = 3.03-3.55, P = .008-.027). Venous-origin false-positives (n = 59) with contrast-to-noise ratio and morphology features similar to small-sized (≤14 mm3 P = .544) true-positives occurred more frequently in SPACE images (P < .001). CONCLUSIONS: Small intraparenchymal veins may confound the diagnosis of enhancing lesions on postgadolinium black-blood SPACE images.

Stroke Mimics in the Acute Setting: Role of Multimodal CT Protocol.

BACKGROUND AND PURPOSE: Ischemic stroke can be mimicked by nonischemic conditions. Due to emphasis on the rapid treatment of acute ischemic stroke, it is crucial to identify these conditions to avoid unnecessary therapies and potential complications. We investigated the performance of the multimodal CT protocol (unenhanced brain CT, CTA, and CTP) to discriminate stroke mimics from acute ischemic stroke. MATERIALS AND METHODS: We retrospectively selected multimodal CT studies performed for clinical suspicion of acute ischemic stroke in our center in a 24-month period, including patients with at least 1 follow-up imaging study (brain CT or MR imaging). Hemorrhagic strokes were excluded. We measured the performance of multimodal CT, comparing the original diagnostic results with the final clinical diagnosis at discharge. RESULTS: Among 401 patients, a stroke mimic condition was diagnosed in 89 (22%), including seizures (34.8%), migraine with aura attack (12.4%), conversion disorder (12.4%), infection (7.9%), brain tumor (7.9%), acute metabolic condition (6.7%), peripheral vertigo (5.6%), syncope (5.6%), transient global amnesia (3.4%), subdural hematoma (1.1%), cervical epidural hematoma (1.1%), and dural AVF (1.1%). Multimodal CT sensitivity, specificity, and accuracy were 24.7%, 99.7%, and 83%. Multimodal CT revealed peri-ictal changes in 13/31 seizures and diagnosed 7/7 brain tumors, 1/1 dural AVF, and 1/1 subdural hematoma. CT perfusion played a pivotal diagnostic role. CONCLUSIONS: Multimodal CT demonstrated low sensitivity but high specificity in the diagnosis of stroke mimics in the acute setting. The high specificity of multimodal CT allows ruling out stroke and thereby avoiding unnecessary revascularization treatment in patients with diagnosis of a stroke mimic.

Brain Tumor-Enhancement Visualization and Morphometric Assessment: A Comparison of MPRAGE, SPACE, and VIBE MRI Techniques.

BACKGROUND AND PURPOSE: Postgadolinium MR imaging is crucial for brain tumor diagnosis and morphometric assessment. We compared brain tumor enhancement visualization and the "target" object morphometry obtained with the most commonly used 3D MR imaging technique, MPRAGE, with 2 other routinely available techniques: sampling perfection with application-optimized contrasts by using different flip angle evolutions (SPACE) and volumetric interpolated brain examination (VIBE). MATERIALS AND METHODS: Fifty-four contrast-enhancing tumors (38 gliomas and 16 metastases) were assessed using MPRAGE, VIBE, and SPACE techniques randomly acquired after gadolinium-based contrast agent administration on a 3T scanner. Enhancement conspicuity was assessed quantitatively by calculating the contrast rate and contrast-to-noise ratio, and qualitatively, by consensus visual comparative ratings. The total enhancing tumor volume and between-sequence discrepancy in the margin delineation were assessed on the corresponding 3D target objects contoured with a computer-assisted software for neuronavigation. The Wilcoxon signed rank and Pearson χ2 nonparametric tests were used to investigate between-sequence discrepancies in the contrast rate, contrast-to-noise ratio, visual conspicuity ratings, tumor volume, and margin delineation estimates. Differences were also tested for 1D (Response Evaluation Criteria in Solid Tumors) and 2D (Response Assessment in Neuro-Oncology) measurements. RESULTS: Compared with MPRAGE, both SPACE and VIBE obtained higher contrast rate, contrast-to-noise ratio, and visual conspicuity ratings in both gliomas and metastases (P range, <.001-.001). The between-sequence 3D target object margin discrepancy ranged between 3% and 19.9% of lesion tumor volume. Larger tumor volumes, 1D and 2D measurements were obtained with SPACE (P range, <.01-.007). CONCLUSIONS: Superior conspicuity for brain tumor enhancement can be achieved using SPACE and VIBE techniques, compared with MPRAGE. Discrepancies were also detected when assessing target object size and morphology, with SPACE providing more accurate estimates.

Supratentorial and pontine MRI abnormalities characterize recessive spastic ataxia of Charlevoix-Saguenay. A comprehensive study of an Italian series.

BACKGROUND AND PURPOSE: The autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS) is an early-onset neurodegenerative disorder caused by mutations in the SACS gene. The disease, first described in Canadian families from Québec, is characterized by cerebellar ataxia, pyramidal tract involvement and peripheral neuropathy. METHODS: Analysis of SACS gene allowed the identification of 14 patients with ARSACS from 13 unrelated Italian families. Clinical phenotype, gene mutations and magnetic resonance imaging (MRI) findings were analysed. RESULTS: We found 16 novel SACS gene mutations, including a large in-frame deletion. The age at onset was in infancy, but one patient presented the first symptoms at age 32. Progression of the disease was variable, and increased muscle tone was mostly recognized in later stages. Structural MRI showed atrophy of the superior cerebellar vermis, a bulky pons exhibiting T2-hypointense stripes, identified as the corticospinal tract (CST), thinning of the corpus callosum and a rim of T2-hyperintensity around the thalami in 100% of cases. The presence of iron or other paramagnetic substances was excluded. Diffusion tensor imaging (DTI) revealed grossly over-represented transverse pontine fibres (TPF), which prevented reconstruction of the CST at this level (100% of cases). In all patients, significant microstructural alterations were found in the supratentorial white matter of forceps, cingulum and superior longitudinal fasciculus. CONCLUSIONS: Our findings further enlarge the genetic spectrum of SACS mutations and widen the study of clinical phenotype. MRI characteristics indicate that pontine changes and supratentorial abnormalities are diagnostic. The over-representation of TPF on DTI suggests a developmental component in the pathogenesis of the disease.

Brain tuberculoma (Mycobacterium africanum): high index of suspicion helps in avoiding biopsy/surgery.

Partial seizures can be due to a growing cerebral lesion, which may be tumoral or inflammatory/infectious in nature. The differential diagnosis is obviously important; increasing immigration to Europe from Africa is leading to an increase of infectious disease involving also the central nervous system. The authors report imaging the a case of a brain tuberculoma due to Mycobacterium africanum mimicking brain tumor, in which diagnosis was possible by inoculum in guinea-pig of material obtained by mediastinal biopsy of enlarged lymph nodes. Specific treatment led to marked reduction in the size of the brain lesion.

How well are hypertension and albuminuria treated in type II diabetic patients?

The purpose of this study was to assess the management of both hypertension and micro/macroalbuminuria in a cohort of type II diabetic patients. In the first 6 months of the year 2000, 5815 diabetic patients were identified through prescriptions for antidiabetic drugs in our sanitary district (191 568 inhabitants). In all, 65% (3810) of these type II diabetic patients were also given prescriptions for antihypertensive drugs. A total of 400 diabetic patients were randomly selected and 171 entered the study (gender: 94/77 M/F; age: 66.6+/-8 years; diabetes duration: 12+/-9 years): 100 patients (group DT) were treated with antihypertensive drugs and 71 (group DU) were untreated. Blood pressure, urine albumin-to-creatinine ratio (ACR), and glycated haemoglobin were measured in the two groups. A total of 80% (57/71) of DU patients were hypertensive (BP>/=130/85 mmHg). Specifically, 24.4% had diastolic hypertension (BP>/=85 mmHg) and 79% systolic hypertension (BP>/=130 mmHg). Only 63% (100/157) of the hypertensive patients were treated with antihypertensive drugs (two drugs/patient on average, range 1-5). In addition, only 13% of the DT patients were adequately controlled (BP<130/85 mmHg), while the others had above target blood pressure levels (14%: 130-139/85-89 mmHg; 40%: 140-159/90-95 mmHg, and 33%>/=160/95 mmHg). Angiotensin converting enzyme inhibitors (ACE-I) and angiotensin receptor blockers (ARB) were included in the antihypertensive medical regimen in 70% of the DT patients (ACE-I: 62%; ARB: 8%; diuretics: 39%; dihydropyridine calcium antagonists: 38%; alpha-blockers: 20%, beta-blockers: 17%; clonidin: 8%; nondihydropyridine calcium antagonists: 5%). Only 33% of type II diabetic patients underwent a screening for microalbuminuria as assessed on clinical records. The same percentage of micro- and macroalbuminuric patients (13.5%) was observed in the DT group, whereas 25% micro vs 3% macro were found in the DU group. In all, 73% of microalbuminuric patients were not on ACE-I/ARB. Hypertensive type II diabetic patients were often left untreated and only a minority of those treated were optimally controlled. The importance of an elevated systolic pressure is underestimated and the number of antihypertensive drugs prescribed insufficient. Screening and treatment of albuminuria are inadequate.

[Inadequate treatment and control of arterial hypertension in patients with type 2 diabetes mellitus]. / L'ipertensione arteriosa non e' adeguatamente trattata e controllata nei pazienti con diabete mellito di tipo 2.

BACKGROUND: Aim of this study is to evaluate the treatment and control of arterial hypertension in patients with type 2 diabetes. METHODS: We identified 5815 diabetic patients in our health-care district (191,568 inhabitants) through prescriptions for insulin and/or hypoglycaemic drugs in the first 6 months of 2000; 3810 of them (65%) also had prescriptions for antihypertensive drugs. We evaluated a randomly selected sample of 171 patients with type 2 diabetes, 100 of whom were receiving antihypertensive drugs (94 males and 77 females, mean age 66.6 +/- 8 years, mean diabetes duration 12+/-9 years). RESULTS: Fifty-seven out of 71 patients not treated with antihypertensive drugs (80.3%) had a BP = 130/85 mmHg; 24.4% of them had a diastolic BP = 85 mmHg and 79% had a systolic BP = 130 mmHg. Thirteen out of 100 treated patients (13%) had a BP < 130/85 mmHg. Among the patients treated with antihypertensive drugs 36% received one drug, 36% two drugs and 28%=3 drugs; mean 1.98 +/- 0.9 drugs/patients. Among the patients treated with monotherapy 36.1% received ACE-inhibitors, 36.1% dihydropyridinic calcium-antagonists, 11.1% alpha-blockers, 11%, diuretics, 2.8% non-dihydropyridinic calcium-antagonists, and 2.8% angiotensin II antagonists. Patients treated with two antihypertensive drugs received more frequently an ACE-inhibitor plus a diuretic (31%) or an ACE-inhibitor plus an alpha-blocker (23%) or an ACE-inhibitor plus a dihydropyridinic calcium-antagonists (20%). A diuretic was used in 40% of the patients with two antihypertensive drugs and in 78% of those with >= 3 drugs. CONCLUSIONS: Many hypertensive type 2 diabetic patients are left untreated and only a minority of those treated reach optimal blood pressure control. The importance of an elevated systolic pressure is underestimated, and the number of antihypertensive drugs prescribed is suboptimal.

[Metabolic effects of changes in dietary sodium intake in patients with essential hypertension]. / Effetti metabolici delle variazioni dell'apporto alimentare di sodio in pazienti con ipertensione essenziale.

BACKGROUND: To evaluate the metabolic effects of modification of sodium intake in patients with essential hypertension. METHODS: Thirteen patients with essential hypertension (10 M, median age 51 yrs, range 21-64) followed in random order a low-sodium and a high-sodium diet (50 mmol Na/day vs 250 mmol/day for two weeks each). At the end of each diet an evaluation was made of 24 hour blood pressure (ABPM, Spacelabs 90207) and serum concentration of: glucose, total and HDL cholesterol, uric acid, lipoproteins A, B, Lp(a), total proteins, albumin. RESULTS: Twenty-four hours systolic and diastolic BP were significantly higher at the end of high sodium diet than of low sodium diet [respectively 132 mmHg (120-161) vs 128 mmHg (109-150); p = 0.008 and 84 mmHg (71-99) vs 81 mmHg (70-95); p = 0.008)]. No significant variations were found as regards serum glucose and lipidic parameters between low and high sodium diets. Serum uric acid was significantly higher following low sodium diet [5.9 mg/dl (4.5-8) vs 4.6 mg/dl (3.4-6.5); p = 0.003)], as well as serum total proteins [7.2 g/dl (6.9-8.2) vs 7 g/dl (6.5-7.8); p = 0.027)]. A significant direct correlation was found between changes of uric acid and total proteins from low to high sodium diet (Spearman's rho = 0.57; p = 0.04). CONCLUSIONS: In patients with essential hypertension a moderate dietary sodium restriction, able to reduce significantly 24 hours arterial pressure, does not worsen serum glucose nor lipids concentration.