Papers by Nicola Magarelli
Journal of Neurosurgery, 2013
Benign neurogenic tumors at the sciatic notch that are purely intrapelvic have rarely been report... more Benign neurogenic tumors at the sciatic notch that are purely intrapelvic have rarely been reported. Because of this tumor's particular position, a transabdominal or combined transabdominal-gluteal approach is usually used to achieve total resection. However, the transabdominal approach carries a remarkable surgical risk because of the manipulation of intraperitoneal organs. Here, the authors describe a 59-year-old woman harboring a purely intrapelvic sciatic notch schwannoma extrinsic to the sciatic nerve, which was totally removed via the infragluteal approach preserving sciatic function. The postoperative course was uneventful. The infragluteal approach can be safely used for the effective resection of intrapelvic benign neurogenic tumors at the sciatic notch that are extrinsic to the sciatic nerve, avoiding the more invasive and risky transabdominal approach.
Journal of Neurosurgery, 2013
Benign neurogenic tumors at the sciatic notch that are purely intrapelvic have rarely been report... more Benign neurogenic tumors at the sciatic notch that are purely intrapelvic have rarely been reported. Because of this tumor's particular position, a transabdominal or combined transabdominal-gluteal approach is usually used to achieve total resection. However, the transabdominal approach carries a remarkable surgical risk because of the manipulation of intraperitoneal organs. Here, the authors describe a 59-year-old woman harboring a purely intrapelvic sciatic notch schwannoma extrinsic to the sciatic nerve, which was totally removed via the infragluteal approach preserving sciatic function. The postoperative course was uneventful. The infragluteal approach can be safely used for the effective resection of intrapelvic benign neurogenic tumors at the sciatic notch that are extrinsic to the sciatic nerve, avoiding the more invasive and risky transabdominal approach.
La radiologia medica
The diagnostic role of Magnetic Resonance Angiography (MRA) was investigated in the study of the ... more The diagnostic role of Magnetic Resonance Angiography (MRA) was investigated in the study of the thoracic and abdominal aorta. Thirty-two patients with different conditions were examined: the thoracic aorta was affected in 7 cases (3 aneurysms, 2 dissections, 2 tumors) and the abdominal aorta in 25 cases (21 aneurysms, 3 stenoses and 1 dissection). Moreover, 2 kinkings and 1 dextroposition of the thoracic aorta were observed as occasional findings, together with 15 abdominal aorta kinking cases. A 1.5-T superconductive magnet (Magnetom, Siemens) with circular polarization body coil and the 2D TOF (FL 18 degrees, TR 30 ms, TE 10 ms, ST 5 mm, 1-mm overlap) technique were used. The images acquired on the coronal and sagittal or parasagittal planes were rotated from -45 degrees to 45 degrees and from 60 degrees to 120 degrees during post-processing, according to MIP. Digital angiography was the gold standard in all cases, angiography and CT were the gold standards for aneurysms, and surgery for the lesions reaching the thoracic aorta. The 2D TOF technique allowed excellent visualization of both the thoracic and the abdominal aorta. In thoracic aorta conditions, MRA always identified aneurysms and assessed their relationship to epiaortic branchings. Moreover, MRA identified 2 cases of thoracic aorta dissection. In one case (1/2) MRA failed to depict aortic wall infiltration by tumor. In 21 abdominal aorta aneurysms, MRA always correctly demonstrated both the extent of the aneurysm and its relationships to renal and iliac arteries. Moreover, the thrombotic aneurysmal component was demonstrated, together with left renal vein course, which was retroaortic in 4 cases. Abnormal course, stenoses (2 cases) and dissection of the abdominal aorta were always identified by MRA.
La radiologia medica
The authors evaluated the role of GdDTPA in magnetic resonance angiography (MRA) of intracranial ... more The authors evaluated the role of GdDTPA in magnetic resonance angiography (MRA) of intracranial vessels. Fifteen patients affected with different conditions underwent MRA of intracranial vessels before and after paramagnetic contrast medium infusion. A superconductive 1.5-T magnet (Magnetom Siemens) was used, and a head circular coil, together with the 3DFT TOF technique. The enhanced exam was performed following the infusion of 0.2 ml/kg of GdDTPA in about 2 minutes, with simultaneous MRA image acquisition. To compare enhanced with unenhanced images relative to signal intensity, the signal increase at the basilar artery and carotid sinus was studied, together with signal-to-noise (S/N) ratio and spatial resolution. During acquisition, enhanced MRA images at the basilar artery showed a mean intensity value of 423.8 +/- 33.2 vs 357.8 +/- 53.2 of unenhanced scans; a statistically significant difference (p < 0.05; p < 0.01) was observed in favor of enhanced images. At the carotid sinus, enhanced MRA showed 184.5 +/- 28.4 mean intensity value vs 190.5 +/- 19.8 of unenhanced exams; no statistically significant difference was observed (p < 0.05; p < 0.01) in favor of unenhanced exams. At the basilar artery the S/N ratio of baseline exams was 1.9 vs 2.2 for enhanced scans; at the carotid sinus S/N ratio was 2.4 (unenhanced) vs 2.3 (enhanced). Thus, MRA allowed better visualization of peripheral branches of arterial (95.6%) and venous vessels, which unenhanced scans always failed to depict; on the other hand, enhanced images exhibited poorer definition of arterial vessels which were never isolated from the background. The simultaneous visualization of arterial and venous vessels, of choroid plexus and mucosae, affect the quality of enhanced angiograms. At present, GdDTPA is the sole contrast medium suitable for MRA intracranial vessels even though, due to its pharmacokinetic features, it is not the optimum medium.
La radiologia medica
This work was aimed at investigating the value of Gd-DTPA to demonstrate distal renal artery bran... more This work was aimed at investigating the value of Gd-DTPA to demonstrate distal renal artery branches with 3D TOF Magnetic Resonance angiography (MRA). Ten volunteers and two patients with proximal-distal renal artery stenoses were studied with MRA; all subjects were studied before and after Gd-DTPA. MRA was performed with a 1.5-T superconductive magnet (Magnetom Siemens); the FISP 3D sequence was used with the following setting: FA 25 degrees, TR 40 ms, TE 6 ms, slice thickness 64 mm with 64 partitions and MA 256 x 256. This setting was not changed from pre- to post-contrast scans. The images acquired on the z axis were rotated, according to the MIP, on the axial and the sagittal axes, from 0 degrees to 180 degrees, with a 15 degrees step. 0.2 ml/kg of Gd-DTPA were injected as bolus during 3D acquisitions; the injection was started half-way through acquisition. To evaluate and compare pre- and post-contrast MRA images, the signal-to-noise (S/N) ratio and the demonstration of the various renal artery segments were studied. Average S/N ratio was 2.3 in the right renal artery and 2.1 in the left renal artery on pre-contrast MRA images, while it was 0.9 in the left renal artery and 0.8 in the right renal artery on post-contrast MRA images. These differences were statistically significant (p < 0.01). As for the demonstration of the distal segments and of the bifurcations, enhanced MRA was no better than unenhanced MRA. As for the demonstration of distal segment stenoses, enhanced MRA proved no better than unenhanced MRA in both patients. To conclude, in our experience MRA after Gd-DTPA failed to allow the systematic demonstration of the distal segments and of the bifurcations of the renal arteries.
International journal of immunopathology and pharmacology
The aim of this study is to assess the biocompatibility of two types of Poly-L-lactic acid (PLLA)... more The aim of this study is to assess the biocompatibility of two types of Poly-L-lactic acid (PLLA) screws (with either hydroxyapatite (HA) or beta-tricalcium phosphate (beta-TCP)) implanted in the left femur of four sheep euthanized at 42, 50, 57 and 84 days after surgery. Titanium screws were also implanted for comparison purposes. No signs of inflammation were seen in the 240 specimens. A rating of "+/-" for macrophages and "-" for neutrophils was assigned to all specimens. All specimens were assigned a rating which ranged from "+/-" to "+++" for fibroblasts and osteoblasts. The presence of macrophages, neutrophils and fibroblasts/osteoblasts was not statistically different for the four implantation periods. PLLA implants with beta-TCP have a biocompatibility comparable to PLLA implants with HA.
Clinical and experimental rheumatology
Septic sacroiliitis is an uncommon joint infection and the diagnosis is often delayed. We present... more Septic sacroiliitis is an uncommon joint infection and the diagnosis is often delayed. We present the first case of a septic arthritis of the shoulder and of the sacroiliac joint in a woman affected by systemic sclerosis, and we reviewed the medical literature since 1997 to 2008 on septic sacroiliitis with a specific microbiological diagnosis other than Mycobacteria and Brucella species.Evidence shows that antibiotic therapy should be continued until full clinical and radiological resolution is achieved.
Journal of Neuroradiology
The authors have optimized the technique of Magnetic Resonance Angiography (MR-angio) in the stud... more The authors have optimized the technique of Magnetic Resonance Angiography (MR-angio) in the study of the origins of the supraaortic arteries. Twenty healthy volunteers, mean age 21.5, were studied with MR-angio of the origins of the supraaortic arteries; a 1 T superconductive magnet (Impact) with body coil was used. All the volunteers were studied using Time of flight (TOF), and two acquisition techniques: single volume FISP (fast imaging with steady-state precession) 3D TONE (titled optimized non-saturating excitation) and double volume FISP 3D TONE with 30% overlapping. The images were acquired on the axial plane following the positioning of three pre-saturation pulses. Regarding the visualization of the different components of the origins of the supraaortic arteries, a statistical analysis was worked out using the Mann Whitney test (p < 0.05); there was no statistically significant difference between two techniques. Regarding the visualization of the various segments (origin,...
La radiologia medica
We optimized the technique of contrast-enhanced Magnetic Resonance Angiography (MRA) with a .5 T ... more We optimized the technique of contrast-enhanced Magnetic Resonance Angiography (MRA) with a .5 T superconductive magnet. Forty patients with normal blood pressure and heart rate gave their informed consent to MRA studies with contrast agent administration. The carotid arteries were studied in 10 patients, the pulmonary arteries in 10, the thoracic aorta in 10 and the abdominal aorta and renal arteries in 10. All the examinations were performed with a .5 T superconductive magnet (Philips T5) acquiring 3D T1-weighted GE sequences with contrast agent administration. The parameters were: TR/TE/FA 13 ms/4 ms/60 degrees; 256 x 256 MA; 2 mm slice thickness; 1 NEX. The contrast agent was administered with an automatic injector (.2 mmol/kg at 1.5 flowrate) after a bolus test to evaluate circulation time. The images were studied by a radiologist rating artery visualization as "good" or "poor" on a multiple choice card. The signal-to-noise ratio was evaluated using regions ...
Journal of Neuroradiology
To verify the hypothesis that a drug that causes vasodilation can contribute to improvement in MR... more To verify the hypothesis that a drug that causes vasodilation can contribute to improvement in MRA spatial resolution. To test this hypothesis, a comparison was made between the images obtained using the high resolution time-of-flight (TOF HR 3D) technique and the TOF 3D MTC TONE technique. From November 1993 to December 1994, we studied 40 patients, of which 20 patients (16 males and 4 females; average age of 10 years; range from 3 to 20 years) we examined after they had inhaled Isoflurane (experimental group), and 20 patients (16 males and 4 females; average age 9.7 years; range from 3 to 12 years) were examined with standard MRA (control group). The vasodilator in both HR MRA and MTC TONE MRA permits a better spatial visualization with respect to the clinical routine MRA. On the other hand, it is true that MTC TONE gives better visualization of the small vessels. In our experience, this preliminary study indicates that with respect to routine MR, the spatial resolution is notably...
European review for medical and pharmacological sciences
Spinal infections (pyogenic or non-pyogenic) are increasing in incidence and are a common cause o... more Spinal infections (pyogenic or non-pyogenic) are increasing in incidence and are a common cause of morbidity in high-risk patients (elderly, immunocompromised patients, diabetic patients, drug addicts, and patients with sickle-cell disease). To provide an overview of the radiological features of spinal infections, focusing on magnetic resonance (MR) imaging, and to illustrate the differential diagnosis. We reviewed the spine imaging of 118 patients with spinal infections from our files. All patients underwent radiography and MR imaging examinations. computed tomography (CT) was performed in 96 patients. MR imaging has greatly contributed to prompt diagnosis, thus allowing implementation of timely appropriate treatment. Prompt diagnosis and treatment are essential to prevent serious bone and joint destruction, and severe neurologic sequelae.
Acta radiologica (Stockholm, Sweden : 1987), Jan 15, 2015
Correct alignment of prosthetic components is the most important factor for the success of total ... more Correct alignment of prosthetic components is the most important factor for the success of total knee arthroplasty (TKA). Dual-energy computed tomography (DECT) may be a reliable method in determining implant position after TKA. To evaluate the accuracy and reproducibility of DECT in determining implant position after TKA. Institutional review board approval was obtained. Forty-five patients (age 75.2 ± 6.4 years) prospectively underwent TKA at our institution between May and December 2012. DECT was performed 1 year after surgery, using an alignment similar to a standing position and generating images at an extrapolated energy of 120 kVp, in order to reduce metal artifacts. Implant position was evaluated by two independent readers. Intra- and inter-observer agreements were calculated. DECT measurements on implant position were compared with the preoperative planning based on radiographs. Additional clinical and DECT findings were taken into account. Metal artifact reduction was judg...
Skeletal Radiology, 2015
Objectives The aim of this ex vivo study was to assess the performance of monoenergetic dual-ener... more Objectives The aim of this ex vivo study was to assess the performance of monoenergetic dual-energy CT (DECT) reconstructions to reduce metal artefacts in bodies with orthopedic devices in comparison with standard single-energy CT (SECT) examinations in forensic imaging. Forensic and clinical impacts of this study are also discussed. Materials and methods Thirty metallic implants in 20 consecutive cadavers with metallic implants underwent both SECT and DECT with a clinically suitable scanning protocol. Extrapolated monoenergetic DECT images at 64, 69, 88, 105, 120, and 130 keV and individually adjusted monoenergy for optimized image quality (OPTkeV) were generated. Image quality of the seven monoenergetic images and of the corresponding SECT image was assessed qualitatively and quantitatively by visual rating and measurements of attenuation changes induced by streak artefact. Results Qualitative and quantitative analyses showed statistically significant differences between monoenergetic DECT extrapolated images and SECT, with improvements in diagnostic assessment in monoenergetic DECT at higher monoenergies. The mean value of OPTkeV was 137.6±4.9 with a range of 130 to 148 keV.
Child's Nervous System, 2015
for personal use only and shall not be selfarchived in electronic repositories. If you wish to se... more for personal use only and shall not be selfarchived in electronic repositories. If you wish to self-archive your article, please use the accepted manuscript version for posting on your own website. You may further deposit the accepted manuscript version in any repository, provided it is only made publicly available 12 months after official publication or later and provided acknowledgement is given to the original source of publication and a link is inserted to the published article on Springer's website. The link must be accompanied by the following text: "The final publication is available at link.springer.com".
Orthopedics, 2015
The number of total knee arthroplasty (TKA) procedures continuously increases, with good to excel... more The number of total knee arthroplasty (TKA) procedures continuously increases, with good to excellent results. In the last few years, new surgical techniques have been developed to improve prosthesis positioning. In this context, patient-specific instrumentation is included. The goal of this study was to compare the perioperative parameters and the spatial positioning of prosthetic components in TKA procedures performed with patient-specific instrumentation vs traditional TKA. In this prospective comparative randomized study, 15 patients underwent TKA with 3-dimensional magnetic resonance imaging (MRI) preoperative planning (patient-specific instrumentation group) and 15 patients underwent traditional TKA (non-patient-specific instrumentation group). All patients underwent postoperative computed tomography (CT) examination. In the patient-specific instrumentation group, preoperative data planning regarding femoral and tibial bone resection was correlated with intraoperative measurem...
La radiologia medica, 2009
The purpose of this paper was to illustrate the role of diagnostic imaging in superficial and dee... more The purpose of this paper was to illustrate the role of diagnostic imaging in superficial and deep fibromatosis through a review of the use of different imaging modalities, including radiography, ultrasound (US), computed tomography (CT), magnetic resonance imaging (MRI), angiography and scintigraphy. In particular, in agreement with published data, it emphasises the crucial role of MRI as the primary modality providing the information needed for management decisions, preoperative planning and follow-up of these lesions.
Child's Nervous System, 2014
Background Mucopolysaccharidoses (MPS) represent a group of inheritable lysosomal storage disease... more Background Mucopolysaccharidoses (MPS) represent a group of inheritable lysosomal storage diseases caused by mutations in the genes coding for enzymes involved in catabolism of different glycosaminoglycans (GAGs). They are clinically heterogeneous multisystemic diseases, often involving the spine. Bony abnormalities of the spine included in the so-called dysostosis multiplex and GAG deposits in the dura mater and supporting ligaments can result in spinal cord compression, which can lead to compressive myelopathy. Spinal involvement is a major cause of morbidity and mortality in some MPS (e.g., MPS IVA, VI, and I), and early radiological diagnosis is critical in preventing or arresting neurological deterioration and loss of function. Discussion Management of MPS, however, requires a multidisciplinary approach because of the multiorgan nature of the disease. Indeed in order to appreciate the relevance and nuances of each other's specialty, radiologists and clinicians need to have a background of common knowledge, rather than a merely compartmentalized point of view. In the interest of the management of spinal involvement in MPS, this review article aims on one hand to provide radiologists with important clinical knowledge and on the other hand to equip clinicians with relevant radiological semiotics.
Journal of Neurosurgery, 2013
Benign neurogenic tumors at the sciatic notch that are purely intrapelvic have rarely been report... more Benign neurogenic tumors at the sciatic notch that are purely intrapelvic have rarely been reported. Because of this tumor&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;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;#39;s particular position, a transabdominal or combined transabdominal-gluteal approach is usually used to achieve total resection. However, the transabdominal approach carries a remarkable surgical risk because of the manipulation of intraperitoneal organs. Here, the authors describe a 59-year-old woman harboring a purely intrapelvic sciatic notch schwannoma extrinsic to the sciatic nerve, which was totally removed via the infragluteal approach preserving sciatic function. The postoperative course was uneventful. The infragluteal approach can be safely used for the effective resection of intrapelvic benign neurogenic tumors at the sciatic notch that are extrinsic to the sciatic nerve, avoiding the more invasive and risky transabdominal approach.
Journal of Neurology, 2006
Uploads
Papers by Nicola Magarelli