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Biomedical subjects

Giovanni Simonetti

Publications and source records attributed to Giovanni Simonetti.

At least 55 records · Page 3Linked to original sources

Endovascular treatment of a giant superior mesenteric artery pseudoaneurysm using a nitinol stent-graft.

A 68-year-old woman presenting with gastrointestinal bleeding (hematocrit 19.3%) and in a critical clinical condition (American Society of Anesthesiologists grade 4) from a giant superior mesenteric artery pseudoaneurysm (196.0 x 131.4 mm) underwent emergency endovascular treatment. The arterial tear supplying the pseudoaneurysm was excluded using a 5.0 mm diameter and 31 mm long monorail expanded polytetrafluoroethylene (ePTFE)-covered self-expanding nitinol stent. Within 6 days of the procedure, a gradual increase in hemoglobin levels and a prompt improvement in the clinical condition were observed. Multislice CT angiograms performed immediately, 5 days, 30 days and 3 months after the procedure confirmed the complete exclusion of the pseudoaneurysm.

Aged↗

Management of biliary neoplastic obstruction with two different metallic stents implanted in one session.

The efficacy of the "one-step" technique using two different metallic stents (Wallstent and Ultraflex) and associated rate of complications was studied in 87 patients with jaundice secondary to malignant biliary obstruction, with bilirubin level less than 15 mg/dl and Bismuth type 1 or 2 strictures. The study group, composed of 40 men and 47 women with a mean age of 59.4 years (range 37-81 years), was treated with a "one-step" percutaneous transhepatic implantation of self-expanding stents. The cause of the obstruction was pancreatic carcinoma in 38 patients (44%), lymph node metastasis in 20 patients (23%), gallbladder carcinoma in 13 patients (15%), cholangiocarcinoma in 12 patients (14%) and ampullary carcinoma in four patients (5%). A significant reduction in jaundice was obtained in all but one patient, with a drop of total serum bilirubin level from a mean of 13.7 mg/dl to 4.3 mg/dl within the first 4 days. The mean postprocedural hospitalization period was 5.4 days in the Wallstent group and 6.4 days in the Ultraflex group. Mean survival rate was 7.8 months (Wallstent group) and 7.1 months (Ultraflex group). The use of both stents did not reveal any significant difference in parameters tested. The implantation of these self-expandable stents in one session, in selected patients, is clinically effective, devoid of important complications and cost-effective due to the reduction in hospitalization.

Adult↗

Bronchobiliary fistula treated by self-expanding ePTFE-covered nitinol stent-graft.

A 71-year-old man, who had undergone right hepatectomy extended to the caudate lobe with terminolateral Roux-en-Y left hepatojejunostomy for a Klatskin tumor, developed bilioptysis 3 weeks postoperatively due to bronchobiliary fistula. Percutaneous transhepatic cholangiography revealed a non-dilated biliary system with contrast medium extravasation to the right subphrenic space through a resected anomalous right posterior segmental duct. After initial unsuccessful internal-external biliary drainage, the fistula was sealed with a VIATORR covered self-expanding nitinol stent-graft placed with its distal uncovered region in the hepatojejunal anastomosis and the proximal ePTFE-lined region in the left hepatic duct. A 10-month follow-up revealed no recurrence of bilioptysis and confirmed the complete exclusion of the bronchobiliary fistula.

Aged↗

Percutaneous vertebroplasty in painful schmorl nodes.

The Schmorl node represents displacement of intervertebral disc tissue into the vertebral body. Both Schmorl nodes and degenerative disc disease are common in the human spine. We performed a retrospective study, for the period from January 2003 to February 2005, evaluating 23 patients affected by painful Schmorl nodes, who underwent in our department percutaneous transpedicular injection of polymethylmethacrylate (vertebroplasty) in order to solve their back pain not responsive to medical and physical management. Eighteen patients reported improvement of the back pain and no one reported a worsening of symptoms. Improvement was swift and persistent in reducing symptoms. Painful Schmorl nodes, refractory to medical or physical therapy, should be considered as a new indication within those vertebral lesions adequately treatable utilizing Vertebroplasty procedure.

Aged↗

Cardiac calcifications: Fetuin-A and other risk factors in hemodialysis patients.

Cardiac calcifications are a frequent finding in hemodialysis for chronic renal failure. Several factors may play a role in the intimal and medial calcification of coronary arteries such as age and some known atherogenetic factors. In addition, Fetuin-A has been proposed as a protective agent through solubilization of calcium phosphate salt. Fetuin-A is also a marker of inflammatory-nutritional state, and its changes could be an expression of this condition. The aim of this cross-sectional study is to evaluate the relative importance of risk factors of calcifications with special regard to Fetuin-A. The study was conducted with 132 hemodialysis patients. They were subjected to multislice computed tomography for evaluation of calcium deposits in the heart. In addition, the patients were sampled for evaluation of calcium-phosphate parameters, lipid profile, nutritional and inflammatory markers, and also Fetuin-A. There was a wide variability of the extent of calcium deposits expressed as Agatston score, with only 9.3% of patients without calcifications. Age, hemodialysis age, sex, calcium-phosphate parameters, and lipid profile were important risk factors, together with nutritional and inflammatory status of the patients. An inverse correlation between coronary calcium score and Fetuin-A emerged from a multiple regression analysis. However, there was no significant difference in serum Fetuin-A among different grades of calcium score. By dividing the patients in tertiles of serum Fetuin-A, an association between low levels of Fetuin-A and high calcification score was found. Fetuin-A as dependent variable was strictly linked to prealbumin serum levels. In addition, there was a clear link between cardiac calcification scores and inflammatory-nutritional markers. Serum calcium and treatment with calcitriol emerged as predictive variables of coronary score.Fetuin-A could be involved in the process of calcification both in the case of markedly low serum levels, due to decreased prevention of calcium phosphate precipitation, and also as a marker of inflammation, a well-known risk factor of atherogenesis. Treatment with intravenous calcitriol could marginally enhance cardiac calcifications, probably through its hypercalcemic effect.

Blood Proteins↗

Percutaneous kyphoplasty: indications and technique in the treatment of vertebral fractures from myeloma.

AIMS AND BACKGROUND: The purpose of our research was to assess the effectiveness and safety of percutaneous kyphoplasty, the new method of treatment for pain deriving from vertebral compression fractures due to myeloma. METHODS: We treated 3 patients with pain refractory to conventional medical therapy (analgesics, bed-rest, bracing with orthopedic devices for more than 4 weeks), localized in the lumbar area, painful to the touch and in the absence of neurological signs. RESULTS: The method demonstrated a swift pain relief associated with an evident augmentation in the resistance and restoration of the vertebral body's physiological shape. Polymethylmethacrylate leaks were not observed in the epidural or foraminal area, nor were complications such as pulmonary embolism for involvement of the venous plexus or related to phenomenon of infections due to the procedure, or toxicity due to the polymethylmethacrylate. CONCLUSIONS: Kyphoplasty was found to be an effective alternative, simple and safe in the treatment of vertebral collapse consequent to multiple myeloma. The same injection of polymethylmethacrylate can be done before the radiotherapy treatment, thereby synergizing its delayed analgesic action to pain, or after the failure or in the case of local recurrence.

Fractures, Spontaneous↗

Perfusion MRI of the lung: preliminary results in twenty healthy volunteers.

PURPOSE: This study attempted to assess the feasibility and the accuracy of lung contrast enhanced magnetic resonance (MR) perfusion imaging in the evaluation of 20 healthy volunteers and to correlate the intensity/time (I/T) curves with the pulmonary physiological criteria. MATERIAL AND METHODS: After an informed consensus, twenty no-smoker subjects, without any present or past pulmonary pathologies, were studied by means of an ultra-fast gradient echo sequence after a Gd-DTPA intravenous administration. The acquisitions were performed in coronal and sagittal planes, in supine and prone position, in breath holding. An ulterior acquisition was performed in only five cases immediately after 2-3 minutes of physical exercise. RESULTS: All the examinations, reviewed according to a visual score by three independent observers, resulted fairly interpretable. The I/T curves, obtained in post-processing evaluation, have the same trend in all cases and are correlated to the lung physiological criteria: the position changes of the examined subjects confirm the gravity dependence of perfusion; the study performed immediately after physical exercise showed a reduction of perfusion in the whole lung due to a transitory massive shift of blood mass from visceral to muscular districts. CONCLUSIONS: The extremely short acquisition and post-processing time coupled with a simple feasibility, the ability to detect physiological perfusional changes, the minimal invasivity indicate a potential clinical use of MR in the pulmonary perfusion defects evaluation.

Adult↗

Cineradiographic study of spine during cycling: effects of changing the pedal unit position on the dorso-lumbar spine angle.

PURPOSE: Low back pain is a frequent pathology among bicyclists, probably due to unappropriate saddle position. This radiographic study was conducted to evaluate dorso-lumbar angular values in two different pedal unit positions; the first one in a bicycle frame type with pedals in front of the saddle axis and the second one with the pedals behind the saddle axis, in order to define the most physiological sitting position. MATERIALS AND METHODS: Ten voluntary healthy adults, ranging in age between 21 to 45 years, were randomly choosen among a group of cyclist not involved in competition and underwent serial fluoroscopic studies while cyclists sit on two different saddles of a prototype cyclette; dorso-lumbar angles at both different sitting positions were measured on film according to modified Lippmann-Cobb method using as reference the upper somatic limitant of the eleventh or twelth dorsal vertebra and the lower somatic limitant of the third lumbar vertebra. RESULTS: Statistical analysis of the measured angles demonstrates that the differences between the dorso-lumbar spine angle in the different saddle positions are statistically significative with a coefficient correlation equals to 0.64015 and p>0.01; angular values are more physiological in the second position with pedal unit behind the saddle axis. CONCLUSIONS: The incidence and importance of low back pain in cyclists can be reduced with appropriate pedal unit position; the position with pedals behind the saddle axis permits more physiological spine angles in comparison with the classic one having the pedals in front of the saddle axis; this fact is due to a different pelvic position which coincides with lumbar angles.

Adult↗

Technetium-99m tetrofosmin scintigraphy in pediatric osteogenic sarcoma.

Technetium-99m tetrofosmin (TF) is a myocardial perfusion agent that has recently proved useful also as tumor-seeking tracer. The aim of this study was to make a preliminary assessment of TF scintigraphy in osteosarcoma, with regard to tumor detection and monitoring of response to preoperative chemotherapy (PC). Current clinical investigations have demonstrated that the curability of osteogenic sarcoma mainly depends on the response to PC, and the percentage of tumor necrosis is the most powerful prognostic factor. However, this is difficult to assess radiologically, and it can only been obtained by histologic examination after surgery. Fourteen patients (7 males, age range: 1-17 years) with recently discovered osteosarcoma of the extremities or the pelvis were injected with TF ( approximately 7.4 MBq/kg i.v., never in the affected limb): a dynamic acquisition (20 min) was performed immediately post-injection, followed by static planar views of the involved area. Six patients were studied twice: before and after PC. Images were evaluated visually and quantitatively using regions of interest over lesion (L) and controlateral normal tissue (N). All initial TF scans demonstrated very rapid tumoral uptake (1-2 min post-injection); the mean L/N ratio at 20 min was 2.76+/-1.05. The post-PC scans showed reduced uptake in 4 patients, unchanged in one and increased accumulation in one case, with a strong correlation between the percentage change in L/N and the percentage of tumor necrosis. Our preliminary data indicate that TF is able to detect osteosarcoma; further studies including larger population is need to confirm its usefulness in non-invasively predicting response to PC.

Adolescent↗

Pyriformis muscle syndrome: CT/MR findings in the percutaneous therapy with botulinic toxin.

PURPOSE: The aim of our study was to evaluate the diagnostic capabilities of computed tomography (CT) and magnetic resonance (MR) imaging in pyriformis syndrome (PS) and the long-term outcomes of CT-guided percutaneous treatment with botulinum. PS is a cause of sciatica and disability. The pain is usually increased by muscular contraction, palpation or prolonged sitting. MATERIAL AND METHODS: Thirty-four patients suffering from PS, suspected on the basis of clinical and electrophysiological criteria and after imaging examinations had excluded other causes of sciatic pain, had positive lidocaine tests and were treated by intramuscular injection of botulinum toxin type A (BTX-A) under CT guidance. MR sequences was performed in nine patients before treatment and after three months to evaluate the extent of muscle denervation. RESULTS: In 30 cases relief of symptoms was obtained after 5-7 days. In four patients insufficient pain relief warranted a second percutaneous treatment which proved clinically successful. No complications or side effects were recorded after BTX-A injection. The MR examination demonstrated a change in signal intensity of the muscle in seven patients due to denervation, whereas in the remaining two cases only atrophy was detected. Larger series are necessary to confirm these preliminary results. CONCLUSIONS: CT-guided BTX-A injection in the pyriformis muscle is an emergent and feasible technique that appears to yield excellent local therapeutic effects without the risk of imprecise injection.

Adult↗

MRI lung perfusion 2D dynamic breath-hold technique in patients with severe emphysema.

BACKGROUND: Our aim was to prospectively evaluate a semi-quantitative pulmonary perfusion MR technique using a breath-hold 2D dynamic sequence in patients with severe pulmonary emphysema. MATERIALS AND METHODS: Thirty patients with severe emphysema were studied with pulmonary perfusion MRI. Results were compared with those obtained through lung scintigraphy, considered as the gold standard technique. We used Fast Field Echo (FFE) pulse sequences in the coronal and sagittal planes, with paramagnetic contrast agent administration. Ten healthy volunteers were studied as the control group. Three thoracic radiologists independently reviewed all the subjects, evaluating the site and entity of perfusional defects. Peak intensity and apparent mean transit time were calculated. RESULTS: MRI showed high sensitivity (86.7%) and good specifity (80.0%) in detecting perfusional defects. We observed lower peak signal intensities in emphysematous regions. CONCLUSION: Lung perfusion MR is a potential alternative to Nuclear Medicine in the evaluation of severe pulmonary emphysema.

Adult↗

Axial loading MRI of the lumbar spine.

BACKGROUND: The aim of our study was to evaluate the incoming interrelations between chronic low back pain and biomechanical changes of the lumbar spine, using an MRI-compatible axial-loading device mimicking the standing position. MATERIALS AND METHODS: Fifty consecutive patients (28 males and 22 females), with both chronic low pack pain and recurrent painful blockages, were selected and studied using a 1.5 T Gyroscan Intera Philips MRI unit (Philips, Best, Holland) and a dedicated axial loading apparatus (MIKAI manufacturing, Genoa, Italy). RESULTS: After loading, no significant modifications occurred in ten patients (20%), a spinal stenosis was seen in 18 patients (45%), an increase in the discal protrusions or hernias was detected in 8 patients (20%) and a significant accentuation of the spondylolisthesis was observed in 6 patients (15%). CONCLUSION: Axial loading MRI provides valuable information for specific non-invasive or operative management of low back pain.

Female↗

[Cardiac MRI with SENSE technology: study of ventricular and valvular functionality in 30 patients].

PURPOSE: The latest innovation in MR imaging is SENSE (SENSitivity Encoding), a technology providing an important solution for the time necessary for signal encoding. In the SENSitivity Encoding (SENSE) approach, an array of multiple, simultaneously operated receiver coils is used for signal acquisition. In particular, the efficacy of SENSE technology is able to reduce the number of phase encodings by a factor (named R factor or Reduction factor) and to evaluate the same k space with fewer readout lines obtaining higher spatial and temporal resolution. MATERIALS AND METHODS: An heterogeneous group of 30 patients with a variety of clinically proven diagnoses underwent Cardiac MR with SENSE technology to evaluate the technique's diagnostic efficacy. The sequences used were "Balanced" Ultrafast Gradient Echo (B-FFE) characterised by a hyper-intense blood signal with multislice multiphase and single slice multiphase acquisitions. RESULTS: In addition to reducing scan times, SENSE technology improved spatial and temporal resolution (40 frames/cardiac cycle) providing optimal dynamic evaluation of valve structures and wall kinesis. Furthermore, the use of the SENSE technique with B-FFE sequences (sB-FFE) enabled the qualitative evaluation of abnormal blood movements and transvalvular flows. CONCLUSIONS: The considerable time savings allowed by SENSE technology and the clear improvement in image quality constitute a step forward in cardiac MR imaging. The possibility of executing morphologic, dynamic, perfusional and spectroscopic studies in the same MR examination session with short acquisition times and good image quality are becoming more feasible.

Adult↗

Percutaneous kyphoplasty: new treatment for painful vertebral body fractures.

AIMS AND BACKGROUND: The purpose of this study was to assess the effectiveness and safety of Percutaneous Kyphoplasty as a new method of treatment for pain deriving from vertebral compression fractures (VCF). PATIENTS AND METHODS: We treated sixteen patients with unremitting pain over spine, which increased particularly when pressure was applied over the spinous process, in absence of neurological signs and refractory to conventional medical therapy. RESULTS: The method demonstrated swift pain relief associated with an evident augmentation in the resistance and restoration of the vertebral body's physiological shape. Polymethylmethacrylate (PMMA) leakages were not observed in the epidural space or foraminal area. The presence of complications such as pulmonary embolism involving the venous plexus, toxicity due to PMMA and infection due the procedure did not occur. CONCLUSION: Kyphoplasty is an effective, alternative, simple and safe treatment of vertebral collapse consequent to osteoporosis. aggressive haemangiomas, myelomas and metastases.

Aged↗

Non-invasive diagnostic and functional evaluation of cardiac and pulmonary involvement in systemic sclerosis.

BACKGROUND: The aim of the present study was to evaluate the role of non-invasive methods in the early detection of pulmonary and cardiac involvement in Systemic sclerosis (SSc) and to identify clinical and/or instrumental patterns of prognostic value. PATIENTS AND METHODS: Twenty female patients affected by SSc (8 with diffuse cutaneous SSc and 12 with limited cutaneous SSc) were enrolled in our study. Cardiac and pulmonary involvement (respiratory function tests and carbon monoxide lung diffusion [DLCO], chest radiography, high resolution computed tomography [HRCT] and lung perfusion magnetic resonance) were evaluated. RESULTS: All 18 patients studied with respiratory function tests showed a significant reduction of DLCO. HRCT was considerably more sensitive than traditional chest radiography (59% versus 28%; p<0.05). Lung perfusion MRI revealed normal findings in 15 patients. Abnormal lung perfusion MRI results were found only in 3 patients. Angina pectoris with electrocardiographic and scintigraphic ischemic changes, severe regional wall motion abnormalities and complex arrhythmias seemed to be associated with poor prognosis. CONCLUSION: Taken together these results indicate that a pulmonary involvement occurs both in limited and in diffuse cutaneous SSc patients and develops, in 83% of the cases, without any regional lung perfusion abnormality. Furthermore, cardiac involvement is detected in 65% of the cases as a consequence of a range of noxious events including myocardial ischemia, fibrosis and pressure overload which may result in ventricular dysfunction and arrhythmias. Lung perfusion MRI should be considered as a complementary diagnostic method for the functional evaluation of these symptoms in systemic sclerosis.

Adult↗

Thorax: new millennium vascular imaging.

In recent years the technological development of computed tomography (CT) and magnetic resonance (MR) has promoted new improvements in diagnosis by means of imaging. In particular the introduction of multislice CT and MR angiography (MRA) has broadened the non-invasive diagnostic possibilities in the vascular study of the thorax. The new technological developments of CT and MR enable functional studies as well. Recent studies have demonstrated that CT and MR are as accurate in finding the vascular anomalies as digital subtraction angiography, while they are more precise in recognising possible associated pathologies which modify therapeutic treatment (for example of the trachea, bronchi, oesophagus etc.). There are many vascular structures in the thorax which need to be considered (aorta, pulmonary and coronary arteries, pulmonary veins, vena cava). The field of associated pathologies is also broad, and includes congenital vascular anomalies, vascular malformations, aorta dissection, vascular compression syndromes, atherosclerotic stenosis or occlusions, and pulmonary embolism. In pulmonary embolism some authors have demonstrated the utility of CT, in showing pulmonary segmental perfusion defects, and MRA, in identifying sub-segment pulmonary embolism. In this paper we analyse the most important CT and MR applications for the study of vascular thoracic diseases and compare them with other diagnostic techniques. We also evaluate the morpho-functional capabilities of CT and MR in this field.

Humans↗

Radiofrequency Heat Ablation and Vertebroplasty in the treatment of neoplastic vertebral body fractures.

BACKGROUND: Metastatic cancer is the most common malignant disease of the skeletal system. Traditionally, conventional fractionated external beam radiotherapy has been the treatment of choice. Recently, minimally invasive surgical techniques (MISS) have been added to the therapeutic armamentarium. The purpose of our study was to assess the effectiveness and safety of Radiofrequency Heat Ablation and Vertebroplasty in the treatment of neoplastic Vertebral Compressive Fractures (VCF). The aim of radiofrequency heat ablation is to destroy the tumor tissue before stabilizing the vertebra through the intrasomatic injection of cement. PATIENTS AND METHODS: We treated patients with unremitting pain over spine, in absence of symptomatic spinal cord or roots compression and refractory to conventional therapeutic options such as radiation therapy, chemotherapy, surgery and use of analgesics. RESULTS: The method demonstrated swift pain relief associated with an evident augmentation in the weight-bearing resistance. CONCLUSION: The association of Radiofrequency Heat Ablation and Vertebroplasty is an effective, simple and safe treatment of vertebral collapse consequent to metastases.

Aged↗

Correlation of diffusion-weighted MR imaging with cellularity of renal tumours.

BACKGROUND: Diffusion is a physical process based on the random movement of water molecules known as Brownian movement. Diffusion-weighted imaging (DWI) is a magnetic resonance (MR) technique that provides information about the biophysical properties of tissues such cell organization and density, microstructure and microcirculation. MATERIALS AND METHODS: Twenty healthy volunteers and 18 patients with renal tumor were enrolled in our study. The DWI was obtained before contrast media injection with a single-shot SE EPI Inversion Recovery (IR) sequence. The tumor cellularity of each resected lesion was evaluated. RESULTS: The mean apparent diffusion coefficient (ADC) value of renal tumors was significantly lower than the mean ADC value of normal renal parenchyma. In our series, the mean ADC value of renal tumors did not significantly correlate with tumor cellularity, but correlated with histological architecture. CONCLUSION: These preliminary results indicate the utility of DWI in the acquisition of tissue characterization data of renal masses using a minimal acquisition time (17 sec).

Adult↗