Marco Zanetti - Academia.edu (original) (raw)

Papers by Marco Zanetti

American Journal of Roentgenology, 2011

Molecules

Carbon-based materials with different morphologies have special properties suitable for applicati... more Carbon-based materials with different morphologies have special properties suitable for application in adsorption, catalysis, energy storage, and so on. Carbon spheres and carbon monoliths are also nanostructured materials showing promising results. However, the preparation of these materials often require the use of a template, which aggravates their costs, making the operations for their removal complex. In this work, hollow carbon microspheres and carbon monolith were successfully prepared via carbonization of hyper-crosslinked polymer based on either cyclodextrins or amylose, in a template-free way. The carbons obtained are of the microporous type, showing a surface area up to 610 m2/g, and a narrow pore distribution, typically between 5 and 15 Å.

American Journal of Roentgenology

The objective of our study was to compare MRI findings in the sacroiliac joints of postpartum wom... more The objective of our study was to compare MRI findings in the sacroiliac joints of postpartum women (as a model of mechanical changes) and women with known axial spondyloarthritis (as an inflammatory model). For this prospective multicenter age-matched, case-control study, sacroiliac joint MRI examinations of 30 healthy women (mean age, 34.0 years) in the early postpartum period (mechanical group) and 30 age-matched women (mean age, 33.8 years) with known axial spondyloarthritis (retrospective inflammatory group) were compared. Blinded to clinical information, readers assessed MR images using the following scoring systems: Spondyloarthritis Research Consortium of Canada (SPARCC) MRI index, Berlin method, Assessment of Spondyloarthritis International Society (ASAS) criteria, and SPARCC MRI structural score. Descriptive statistics as percentages of the different findings (i.e., bone marrow edema [BME], erosion, fatty bone marrow replacement, backfill, ankylosis) and scores between groups and between delivery modes were compared. In the postpartum group, 63.3% (19/30) of women showed BME around the sacroiliac joints compared with 86.7% (26/30) of women in the spondyloarthritis group (based on ASAS criteria). Erosions were uncommon in the postpartum group (10.0% [3/30] postpartum vs 56.7% [17/30] spondyloarthritis). Fatty bone marrow replacement, backfill, and ankylosis were not seen in the postpartum group. In subjects with positive MRI findings for sacroiliitis based on ASAS criteria, the SPARCC MRI index (mean ± SD, 13.6 ± 14.5 vs 13.0 ± 10.7; p = 0.818) and Berlin method (4.5 ± 3.0 and 5.5 ± 3.5, p = 0.378) were not different between the postpartum and spondyloarthritis groups. Scores were not different between birth modalities. Pregnancy-induced BME at the sacroiliac joints, as a result of prolonged mechanical stress, was present in 63.3% of women who underwent MRI during the early postpartum period and may mimic sacroiliitis of axial spondyloarthritis.

Skeletal Radiology

To compare the hindfoot alignment measured on standing HAV radiographs (Saltzman view) and on non... more To compare the hindfoot alignment measured on standing HAV radiographs (Saltzman view) and on non-weight-bearing coronal MR images. The apparent moment arm was measured on weight-bearing conventional radiographs (Saltzman views) and on MRIs of the ankle in 50 consecutive patients (mean age, 54 years; age range, 18-77 years). The evaluation was performed independently by three readers using analogous reference points for both methods. Positive values were assigned when the deepest point of the calcaneus was lateral to the tibial axis as valgus, negative values as varus. The intertechnique agreement and correlation for the measurements performed with HAV radiographs and MRI were assessed for each reader using the Bland-Altman method and the Pearson correlation coefficient, respectively. The interobserver agreement was assessed using the intraclass correlation coefficient. The means of apparent moment arms, with the standard deviation (SD) in parentheses, of three readers were +2.0 (±8.4) mm, +1.5 (±6.6) mm and -1.4 (±8.2) mm on HAV radiographs and +4.6 (±7.4) mm, +6.3 (±5.3) mm and +5.4 (±6.4) mm on MRI. The Bland-Altman analysis found a systematic bias for all three readers, corresponding to an overestimation of measurements with MRI (systematic bias ranging from 2.6 to 4.8 mm). The intertechnique correlation was found moderate to high. The Pearson coefficients for the three readers were 0.75, 0.64 and 0.65. The interobserver agreement among the three readers was 0.72, 0.77 and 0.68 for HAV, MRI and both modalities together, respectively. Hindfoot alignment can be estimated on MRI but the correlation between the values on HAV radiographs and MR images is only moderate with a tendency to increased positive values (valgization) on MR images.

Seminars in Musculoskeletal Radiology

European radiology, Jan 20, 2016

To prospectively compare T1-weighted fat-suppressed spin-echo magnetic resonance (MR) sequences a... more To prospectively compare T1-weighted fat-suppressed spin-echo magnetic resonance (MR) sequences after gadolinium application (T1wGdFS) to STIR sequences in patients with acute and chronic foot pain. In 51 patients referred for MRI of the foot and ankle, additional transverse and sagittal T1wGdFS sequences were obtained. Two sets of MR images (standard protocol with STIR or T1wGdFS) were analysed. Diagnosis, diagnostic confidence, and localization of the abnormality were noted. Standard of reference was established by an expert panel of two experienced MSK radiologists and one experienced foot surgeon based on MR images, clinical charts and surgical reports. Patients reported prospectively localization of pain. Descriptive statistics, McNemar test and Kappa test were used. Diagnostic accuracy with STIR protocol was 80% for reader 1, 67% for reader 2, with contrast-protocol 84%, both readers. Significance was found for reader 2. Diagnostic confidence for reader 1 was 1.7 with STIR, 1....

Radiology, 2001

To evaluate the clinical outcome of edema-like bone marrow abnormalities seen on magnetic resonan... more To evaluate the clinical outcome of edema-like bone marrow abnormalities seen on magnetic resonance (MR) images of the foot when their cause is unknown. The clinical outcome of 31 patients (15 female patients, 16 male patients; mean age, 51; range, 10-79 years) with edema-like bone marrow abnormalities on MR images of the foot was determined. The relevance of three different edema patterns was compared: (a) exclusively ill-defined edema-like zones, (b) edema-like zones plus well-defined necrosis-like zones, and (c) edema-like zones plus linear structures indicating possible fractures. The different edema patterns were compared with persistence of pain. Fifty-four percent of all patients had pain persisting after 1 year, as calculated with the Kaplan-Meier method. The duration of pain in the various subgroups varied significantly (P =.049, log-rank test). The subgroup of patients with a well-defined necrosis-like zone had substantially longer-lasting pain than those with edema-like abnormalities only (n = 16) (P =.065). Only one of seven patients with a well-defined necrosis-like zone (n = 7) was pain free after 1 year. Conversely, patients with possible stress fracture (n = 8) had shorter pain compared with those with edema-like abnormalities only (P =.036); six of eight patients were pain free after 1 year. Edema-like bone marrow abnormalities of the foot predict long-lasting pain. Analysis of the image patterns of such abnormalities allows prediction of the clinical outcome to a certain degree.

Radiology, Jun 1, 2005

To prospectively evaluate magnetic resonance (MR) imaging findings of abductor tendons and muscle... more To prospectively evaluate magnetic resonance (MR) imaging findings of abductor tendons and muscles in asymptomatic and symptomatic patients after lateral transgluteal total hip arthroplasty (THA). The institutional review board approved the study, and all patients provided informed consent. Two musculoskeletal radiologists blinded to clinical information analyzed triplanar MR images of the greater trochanter obtained in 25 patients without and 39 patients with trochanteric pain and abductor weakness after THA. Tendon defects, diameter, signal intensity, and ossification; fatty atrophy; and bursal fluid collections were assessed. In 14 symptomatic patients, MR imaging and surgical findings were correlated. Differences in the frequencies of findings between the two groups were tested for significance by using chi2 analysis. Tendon defects were uncommon in asymptomatic patients and significantly more frequent in symptomatic patients: Two asymptomatic versus 22 symptomatic patients had gluteus minimus defects (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; .001); four asymptomatic versus 24 symptomatic patients, lateral gluteus medius defects (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; .001); and no asymptomatic versus seven symptomatic patients, posterior gluteus medius defects (P = .025). In both patient groups, tendon signal intensity changes were frequent, with the exception of those in the posterior gluteus medius tendon, which demonstrated these changes more frequently in symptomatic patients (in 23 vs five asymptomatic patients, P = .002). Tendon diameter changes were frequent in both groups but significantly (P = .001 to P = .009) more frequent in symptomatic patients (all tendon parts). Fatty atrophy was evident in the anterior two-thirds of the gluteus minimus muscle in both groups, without significant differences. In the posterosuperior third of the gluteus minimus muscle, however, differences in fatty atrophy between the two groups were significant (P = .026). Fatty atrophy of the gluteus medius muscle was present in symptomatic patients only, with significant differences among all muscle parts. Bursal fluid collections were more frequent in symptomatic patients (n = 24) than in asymptomatic patients (n = 8, P = .021). The MR imaging-based diagnosis was confirmed in all 14 patients who underwent revision surgery. Abductor tendon defects and fatty atrophy of the gluteus medius muscle and the posterior part of the gluteus minimus muscle are uncommon in asymptomatic patients after THA.

Arthroscopy the Journal of Arthroscopic Related Surgery Official Publication of the Arthroscopy Association of North America and the International Arthroscopy Association, Jan 5, 1998

A case of uncommon fluid extravasation during knee arthroscopy leading to a swelling of the groin... more A case of uncommon fluid extravasation during knee arthroscopy leading to a swelling of the groin, scrotum, and penis, with massive intraperitoneal and retroperitoneal fluid accumulation is reported. A defective pump pressure sensor relay was found to be the cause of uncontrolled fluid delivery with excessive intra-articular pressure increase. The literature reports several cases of extravasation of irrigation fluid into the calf without any sequelae. Our patient experienced proximal expansion of the fluid that expanded along the vastus intermedius and shunted into the retroperitoneal and intraperitoneal space. There was no clinical evidence of compartment syndrome despite the excessive amount of extravasation in the thigh. Diuretics were administrated, and the fluid was excreted within 36 hours. The patient suffered of no further sequelae.

Radiology, Aug 1, 2002

To compare short inversion time inversion-recovery (STIR) and T1-weighted contrast material-enhan... more To compare short inversion time inversion-recovery (STIR) and T1-weighted contrast material-enhanced fat-suppressed spin-echo magnetic resonance (MR) sequences for depiction of bone marrow abnormalities of the foot and ankle. Fifty-one consecutive patients with bone marrow abnormalities depicted on turbo STIR images were examined with additional T1-weighted contrast-enhanced (0.1 mmol/kg gadopentetate dimeglumine) MR imaging with fat suppression. Volume and signal difference-to-noise ratio (SDNR) were measured. An additional qualitative analysis was performed by two experienced musculoskeletal radiologists to correlate the presence or absence of ill-defined edema-like zones, well-defined zones, and cystlike zones. Diagnoses determined with MR findings with each sequence were compared with the results of a review panel. Correlation coefficients (r(2)) and paired t tests were calculated for all measurements. Agreement percentages and kappa values were calculated for inter- and intraobserver reproducibility. Regarding volume of bone marrow abnormalities, a high correlation (r(2) = 0.98) of both sequences was found. SDNR was substantially higher on T1-weighted contrast-enhanced images than on STIR images (mean, 125.9 vs 95.4; P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;.001). The qualitative analysis demonstrated identical imaging patterns with both sequences in 96% (79 of 82, kappa = 0.38) of ill-defined zones, in 88% (72 of 82, kappa = 0.76) of well-defined zones, and in 98% (80 of 82, kappa = 0.84) of cystlike zones. Interobserver reproducibility of the three imaging patterns was similar for both sequences. The kappa values for these three zones with STIR sequence were 0.55, 0.68, and 0.69, and those for the T1-weighted contrast-enhanced MR sequence were 0.49, 0.73, and 0.58, respectively. Diagnoses determined with MR findings were equal with both sequences in 94% (80 of 85) of involved bones. STIR images and T1-weighted contrast-enhanced fat-suppressed MR images demonstrate almost identical imaging patterns, and diagnoses determined with these findings show little difference.

Rofo Fortschr Rontgenstrahl, 2005

Seminars in musculoskeletal radiology, 2016

The spring ligament complex is an important stabilizer of the medial ankle, together with the pos... more The spring ligament complex is an important stabilizer of the medial ankle, together with the posterior tibial tendon (PTT) and the deltoid ligament complex. Lesions in these stabilizers result in acquired adult flatfoot deformity. The spring ligament complex includes three ligaments: the superomedial calcaneonavicular ligament, the medioplantar oblique calcaneonavicular ligament, and the inferoplantar longitudinal calcaneonavicular ligament. Normal MR imaging anatomy of the spring ligament complex and the PTT are described and illustrated in detail. Isolated lesions of the spring ligament complex are rare. In most cases, spring ligament complex lesions are secondary to PTT dysfunction. The best criteria for an injury of the clinically relevant superomedial calcaneonavicular ligament are increased signal on proton-density or T2-weighted sequences with thickening (> 5 mm), thinning (< 2 mm), or partial or complete discontinuity. A thickened ligament can be simulated by the glid...

Radiology, Mar 1, 2003

To assess the effect of prone, supine, and upright weight-bearing body positions on visibility, p... more To assess the effect of prone, supine, and upright weight-bearing body positions on visibility, position, shape, and size of Morton neuroma during magnetic resonance (MR) imaging. Eighteen patients with 20 Morton neuromas underwent MR imaging of the forefoot in prone (plantar flexion of the foot), supine (dorsiflexion of the foot), and upright weight-bearing positions. Visibility (3 = good, 2 = moderate, 1 = poor), position relative to the metatarsal bone, shape, and transverse diameter of Morton neuroma were assessed on transverse T1-weighted MR images. Associations between different body positions and variables of interest were calculated with Wilcoxon signed rank test, chi2 test, and paired Student t test. In the prone position, visibility of all 20 Morton neuromas was rated with a score of 3; visibility in the supine and weight-bearing positions was inferior (mean score, 2.4). All 20 (100%) Morton neuromas changed their position relative to the metatarsal bone between prone and supine and between prone and weight-bearing positions. When compared with the prone position, there was a difference in the shape of all 20 Morton neuromas in the weight-bearing position (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;.001). Between prone (mean transverse diameter of Morton neuroma, 8 mm) and supine (mean transverse diameter of Morton neuroma, 6 mm) positions, the transverse diameter of Morton neuroma significantly decreased by 2 mm (P =.03); between prone and weight-bearing positions, the decrease of the mean transverse diameter was also significant (difference, 2 mm; P =.03). Morton neuroma appears significantly different during MR imaging in prone, supine, or weight-bearing positions. The transverse diameter of Morton neuroma is significantly larger on images obtained in the prone position than it is on images obtained in the supine and upright weight-bearing positions. Visibility of Morton neuroma is best on MR images obtained in the prone position.

Radiology, 2005

To prospectively determine if kinematic magnetic resonance (MR) imaging of the knee may demonstra... more To prospectively determine if kinematic magnetic resonance (MR) imaging of the knee may demonstrate displacement of menisci with tears and, if so, to characterize displaceable and nondisplaceable meniscal tears. The study was approved by the hospital&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s review board, and informed consent was obtained. Forty-two patients (30 men, 12 women; mean age, 36.9 years) with 43 arthroscopically documented meniscal tears visible at 1.5-T MR imaging underwent kinematic MR imaging with an open-configuration 0.5-T MR imager with their knees in supine neutral, supine with 90 degrees flexion and external or internal rotation, and upright weight-bearing positions. Analysis of meniscal movement was performed in different knee positions in the coronal MR imaging plane. Meniscal displacement--that is, meniscal movement of 3 mm or more (in the medial direction for the medial meniscus, in the lateral direction for the lateral meniscus)--was compared with the patient&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s pain level as assessed with a visual analog scale by using analysis of variance. Between the different knee positions, meniscal displacement of 3 mm or more (displaceable meniscal tears) was noted in 18 (42%) of 43 menisci with tears. Simultaneous occurrence of grade II or III ipsilateral collateral ligament lesions was present in all 18 displaceable meniscal tears, whereas a normal-appearing collateral ligament or collateral ligament lesion (grade I) was present in 22 of 25 nondisplaceable tears (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; .05). Displaced menisci most commonly had complex, radial, or longitudinal tear configurations (16 of 18, 89%). Patients with displaceable meniscal tears had significantly more pain than did patients with nondisplaceable meniscal tears (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; .001), independent of the concomitant knee abnormalities. Displaceable meniscal tears usually have longitudinal, radial, or complex configurations; such tears are associated with substantial ipsilateral collateral ligament lesions and pain.