Alfredo Blandino

Cardiovascular autonomic dysfunction in multiple sclerosis is likely related to brainstem lesions

Impairment of cardiovascular autonomic reflexes has been described in multiple sclerosis (MS), and believed reflecting dysfunction of reflex pathways located within the central nervous system. A battery of cardiovascular autonomic tests were performed in 40 patients with definite MS: R-R interval variation test, deep breathing, Valsalva manoeuvre, blood pressure and heart rate responses to standing, sustained handgrip. The results were evaluated by Bayesian analysis, a pattern recognition technique. The patients had also magnetic resonance imaging (MRI) of brain and in 19 subjects of cervical spinal cord. Deep breathing test and sustained handgrip test produced most frequently abnormal results (17.5% and 40%, respectively). However, only 4 patients (10% had two or more tests abnormal, with a very variable pattern. Evaluation by Bayesian analysis revealed 7 patients (17.5%) with definite autonomic dysfunction. A correlation was found between the confidence level obtained by Bayesian analysis, as index of autonomic function, and the Kurtzke brainstem FS score (r = 0.43, P < 0.01). There was a significant association between presence of autonomic dysfunction and clinical (P < 0.02) and MRI (P < 0.005) evidence of brainstem lesions.

Computed tomography halo sign in pulmonary nodules: frequency and diagnostic value.

On computed tomography (CT) scanning, a ground-glass opacity zone surrounding a pulmonary nodule has been named the computed tomography (CT) halo sign. To investigate the frequency and diagnostic value of the CT halo sign, the authors reviewed the CT examinations of 305 patients with proven diseases producing solitary or multiple nodules. The CT halo sign was seen in 22 patients (7%). Eleven patients had a solitary nodule; five patients had multiple nodules; and six patients had nodules associated with areas of pulmonary consolidation, or ground-glass opacity, or both. Solitary nodules were the result of bronchioloalveolar carcinoma (n = 5), tuberculoma (n = 2), squamous cell carcinoma, non-Hodgkin lymphoma, myxovirus infection, and metastasis (n = 1 each). Multiple nodules were the result of metastasis (n = 2), Kaposi sarcoma (n = 2), and Wegener granulomatosis (n = 1). Nodules associated with areas of consolidation or ground-glass opacity were the result of metastasis (n = 2), bronchioloalveolar carcinoma, bronchiolitis obliterans organizing pneumonia, eosinophilic pneumonia, and invasive pulmonary aspergillosis (n = 1 each). The data showed that the CT halo sign is a nonspecific finding. It is known that in immunocompromised patients the CT halo sign should suggest invasive pulmonary aspergillosis, Kaposi sarcoma, and lymphoproliferative pulmonary disorders. However, in immunocompetent patients, the authors found that a solitary nodule with the CT halo sign and pseudocavitations has a high likelihood of being a bronchioloalveolar carcinoma.

Muscle Fat Fraction in Neuromuscular Disorders: Dual-Echo Dual-Flip-Angle Spoiled Gradient-Recalled MR Imaging Technique for Quantification—A Feasibility Study

PURPOSE To prospectively evaluate the muscle fat fraction (MFF) measured with dual-echo dual-flip-angle spoiled gradient-recalled acquisition in the steady state (SPGR) magnetic resonance (MR) imaging technique by using muscle biopsy as the reference standard. MATERIALS AND METHODS After ethics approval, written informed consent from all patients was obtained. Twenty-seven consecutive patients, evaluated at the Neuromuscular Disorders Center with a possible diagnosis of neuromuscular disorder, were prospectively studied with MR imaging of the lower extremities to quantify muscle fatty infiltration by means of MFF calculation. Spin-density- and T1-weighted fast SPGR in-phase and opposed-phase dual-echo sequences were performed, respectively, with 20° and 80° flip angles. Round regions of interest were drawn by consensus on selected MR sections corresponding to anticipated biopsy sites. These were marked on the patients skin with a pen by using the infrared spider light of the system, and subsequent muscle biopsy was performed. MR images with regions of interest were stored on a secondary console where the MFF calculation was performed by another radiologist blinded to the biopsy results. MFFs calculated with dual-echo dual-flip-angle SPGR MR imaging and biopsy were compared by using a paired t test, Pearson correlation coefficient, and Bland-Altman plots. P value of < .05 was considered to indicate a statistically significant difference. RESULTS The mean MFFs obtained with dual-echo dual-flip-angle SPGR MR imaging and biopsy were 20.3% (range, 1.7%-45.1%) and 20.6% (range, 3%-46.1%), respectively. The mean difference, standard deviation of the difference, and t value were -0.3, 1.3, and -1.3 (P > .2), respectively. The Pearson correlation coefficient was 0.995; with the Bland-Altman method, all data points were within the ± 2 SDs limits of agreement. CONCLUSION The results show that dual-echo dual-flip-angle SPGR MR imaging technique provides reliable calculation of MFF, consistent with biopsy measurements.

Contrast-enhanced MR imaging with fat suppression in adult-onset septic spondylodiscitis.

Abstract. Spinal infections typically involve vertebrae as well as discs, and for this reason they are called septic spondylodiscitis. Magnetic resonance imaging is the most sensitive imaging method for the evaluation of this group of spinal diseases. The use of contrast-enhanced T1-weighted sequences with fat suppression, if correctly applied, may increase information provided by MRI. Firstly, this technique allows the primary vertebral focus, which often precedes disc involvement, to be identified at a very early stage. When the disease spreads, T1-weighted fat-suppressed gadolinium dimeglumine (Gd-DTPA) enhanced images provide macroscopic details of the primary vertebral focus, disc involvement patterns, and pathways of infection diffusion. All this information, when correlated with laboratory tests, may be useful in identifying the infectious agents (tuberculous vs piogenic forms), thus enabling a suitable therapy to be started. This technique is also useful in the assessment of the real extension of the disease, providing a clear depiction of paravertebral space involvement and of psoas muscle abscesses. Dangerous complications, such as meningitis, myelitis, and epidural abscesses, may be more promptly diagnosed and fully evaluated with fat-suppressed post-contrast T1-weighted images. Finally, this imaging technique may help to differentiate infectious processes from degenerative disorders, extradural neoplastic processes, and rheumatic diseases.

High-Resolution CT Grading of Tibial Stress Reactions in Distance Runners

OBJECTIVE The purpose of this study was twofold: to determine whether asymptomatic distance runners exhibit cortical tibial abnormalities on CT and to determine the diagnostic accuracy of CT in athletes with medial tibial stress syndrome. MATERIALS AND METHODS A cross-sectional study with high-resolution CT of both tibiae was performed on 41 subjects: 20 asymptomatic distance runners, 11 distance runners with unilateral or bilateral pain due to medial tibial stress syndrome (14 painful tibiae), and 10 volunteers not involved in a sport. The group was composed of 13 women and 28 men, ranging in age from 18 to 26 years. A total of 82 tibiae, 14 painful and 68 painless, were evaluated. On the basis of CT findings, tibiae were classified in three groups, and correlation between CT classification and symptoms was made. RESULTS Among distance runners, the presence of CT abnormalities was found in 14 (100%) of 14 painful tibiae in patients with medial tibial stress syndrome and in 8 (16.6%) of 48 painless tibiae. The difference was statistically significant (p < 0.001, Fishers exact test). Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of CT in diagnosing medial tibial stress syndrome were 100%, 88.2%, 63.6%, 100%, and 90.2%, respectively. CONCLUSION High-resolution CT has high diagnostic accuracy in depicting medial tibial stress syndrome. Cortical abnormalities can also be seen in some asymptomatic distance runners.

Iodine quantification to distinguish clear cell from papillary renal cell carcinoma at dual-energy multidetector CT: a multireader diagnostic performance study.

PURPOSE To investigate whether dual-energy multidetector row computed tomographic (CT) imaging with iodine quantification is able to distinguish between clear cell and papillary renal cell carcinoma ( RCC renal cell carcinoma ) subtypes. MATERIALS AND METHODS In this retrospective, HIPAA-compliant, institutional review board-approved study, 88 patients (57 men, 31 women) with diagnosis of either clear cell or papillary RCC renal cell carcinoma at pathologic analysis, who underwent contrast material-enhanced dual-energy nephrographic phase study between December 2007 and June 2013, were included. Five readers, blinded to pathologic diagnosis, independently evaluated all cases by determining the lesion iodine concentration on color-coded iodine maps. The receiving operating characteristic curve analysis was adopted to estimate the optimal threshold for discriminating between clear cell and papillary RCC renal cell carcinoma , and results were validated by using a leave-one-out cross-validation. Interobserver agreement was assessed by using an intraclass correlation coefficient. The correlation between tumor iodine concentration and tumor grade was investigated. RESULTS A tumor iodine concentration of 0.9 mg/mL represented the optimal threshold to discriminate between clear cell and papillary RCC renal cell carcinoma , and it yielded the following: sensitivity, 98.2% (987 of 1005 [95% confidence interval: 97.7%, 98.7%]); specificity, 86.3% (272 of 315 [95% confidence interval: 85.0%, 87.7%]); positive predictive value, 95.8% (987 of 1030 [95% confidence interval: 95.0%, 96.6%]); negative predictive value, 93.7% (272 of 290 [95% confidence interval: 92.8%, 94.7%]); overall accuracy of 95.3% (1259 of 1320 [95% confidence interval: 94.6%, 96.2%]), with an area under the curve of 0.923 (95% confidence interval: 0.913, 0.933). An excellent agreement was found among the five readers in measured tumor iodine concentration (intraclass correlation coefficient, 0.9990 [95% confidence interval: 0. 9987, 0.9993). A significant correlation was found between tumor iodine concentration and tumor grade for both clear cell (τ = 0.85; P < .001) and papillary RCC renal cell carcinoma (τ = 0.53; P < .001). CONCLUSION Dual-energy multidetector CT with iodine quantification can be used to distinguish between clear cell and papillary RCC renal cell carcinoma , and it provides insights regarding the tumor grade.

Patterns of recurrence of bronchioloalveolar cell carcinoma after surgical resection: a radiological, histological, and immunohistochemical study.

PURPOSE Bronchioloalveolar carcinoma (BAC) is a subtype of lung adenocarcinoma whose incidence is raising. Bronchioloalveolar carcinoma has a tendency to involve diffusely the lung. No agreement exists about whether diffuse bronchioloalveolar carcinoma has a multicentric or unicentric origin. The purpose of this work is to evaluate the correlation between intrapulmonary spread of bronchioloalveolar carcinoma and its histologic and immunohistochemical characteristics. DESIGN Surgical specimens of 20 bronchioloalveolar carcinomas with radiologically proved evolution from focal to diffuse disease were retrieved and reviewed. Patterns of pulmonary spread were defined on the basis of CT and MR imaging examinations. Immunohistochemical studies were performed to investigate the expression of gelatinase A and alpha2-integrin. Correlation between immunohistochemical results and patterns of pulmonary spread was evaluated. Statistical evaluation was performed by using Fisher Exact Test. RESULTS Three histological subtypes of bronchioloalveolar carcinoma were found: mucinous (11 cases), non-mucinous (3 cases), and mixed adenocarcinoma with prominent bronchioloalveolar pattern (6 cases). Three patterns of pulmonary spread were depicted radiologically: parenchymal opacification (11 cases), multiple nodules (7 cases) and mixed pattern (2 cases). Eleven out of 12 mucin-producing versus none out of 8 non-mucin producing cancers developed parenchymal opacification. The difference was statistically significant (P<0.028). A statistically significant difference was also found between the development of parenchymal opacification and the level of alpha2-integrin: 11 out of 13 tumors with negative alpha2-integrin versus none out of 7 with positive alpha2-integrin immunoreactivity (P>0.033). CONCLUSIONS Diffuse bronchioloalveolar carcinoma may develop from a prior focal cancer. Mucinous subtype is the most prone to develop diffuse disease with parenchymal opacification, probably representing aerogenous spread. Low levels of alpha2-integrin receptors were found in bronchioloalveolar carcinoma which developed parenchymal opacification.

De Novo Renal Tumors Arising in Kidney Transplants: Midterm Outcome after Percutaneous Thermal Ablation

PURPOSE To retrospectively evaluate the midterm outcome of patients treated for primary renal cell carcinomas arising in kidney transplants with minimally invasive techniques. MATERIALS AND METHODS The institutional review board of each participating institution approved this retrospective study and waived informed consent. This study was HIPAA compliant. A request for cases through the European Society of Urogenital Radiology network was made to institutions for patients who fit the requirements outlined by the authors, and a prospective follow-up of recipients was performed. Twenty-four tumors were identified that developed in the renal allograft of 20 patients from 11 institutions who were treated with radiofrequency ablation (n = 19) or cryoablation (n = 5) between 2003 and 2010. Maximal diameter of masses was 6-40 mm (median, 19.5 mm). Twenty masses were solid, and four were type 4 cystic masses. Preablation biopsy was performed for solid tumors only. All images and biologic and biopsy reports were retrospectively reviewed. Significant differences were determined by using a paired t test before and after ablation. RESULTS Mean follow-up was 27.9 months (range, 7-71 months). Histopathologic examination revealed papillary carcinoma in 17 patients and clear cell carcinoma in three. Tumors were successfully treated with ultrasonographic guidance in six patients, with computed tomographic guidance in 10 patients, and with both in four patients. One case of infection of the tumor site and one case of transitory genitofemoral nerve injury were the only reported complications. No significant change of renal function was noted. Subsequent imaging follow-up did not reveal any case of recurrence in the ablative site. CONCLUSION Percutaneous thermal ablation of renal tumors occurring in renal grafts is effective, with low morbidity. .

Magnetic resonance imaging findings of osteoid osteoma of the proximal femur

Osteoid osteoma (OO) is a benign bone tumor whose main radiological finding is nidus. OO of the proximal femur can also result in non-specific findings such as hip joint effusion, perinidal bone marrow edema and soft tissue mass. Since the nidus may be difficult to identify with MR, these non-specific findings can lead to erroneous diagnosis. Therefore, MR imaging technique should be optimized in order to identify nidus. Since MR imaging has assumed increasing importance in the evaluation of disorders of the hip, radiologists must be aware of the spectrum of findings of OO of the proximal femur. The aim of this pictorial review is to show the MR imaging findings of intra-articular and extra-articular OO of the proximal femur.

Can Contrast Media Increase Organ Doses in CT Examinations? A Clinical Study

OBJECTIVE The purpose of this article is to quantify the CT radiation dose increment in five organs resulting from the administration of iodinated contrast medium. MATERIALS AND METHODS Forty consecutive patients who underwent both un-enhanced and contrast-enhanced thoracoabdominal CT were included in our retrospective study. The dose increase between CT before and after contrast agent administration was evaluated in the portal phase for the thyroid, liver, spleen, pancreas, and kidneys by applying a previously validated method. RESULTS An increase in radiation dose was noted in all organs studied. Average dose increments were 19% for liver, 71% for kidneys, 33% for spleen and pancreas, and 41% for thyroid. Kidneys exhibited the maximum dose increment, whereas the pancreas showed the widest variance because of the differences in fibro-fatty involution. Finally, thyroids with high attenuation values on unenhanced CT showed a lower Hounsfield unit increase and, thus, a smaller increment in the dose. CONCLUSION Our study showed an increase in radiation dose in several parenchymatous tissues on contrast-enhanced CT. Our method allowed us to evaluate the dose increase from the change in attenuation measured in Hounsfield units. Because diagnostic protocols require multiple acquisitions after the contrast agent administration, such a dose increase should be considered when optimizing these protocols.