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Biomedical subjects

G Simonetti

Publications and source records attributed to G Simonetti.

At least 37 records · Page 2Linked to original sources

DXA vs QCT: in vitro and in vivo studies.

The aim of this study was to evaluate the discrepancy between bone mineral density (BMD) results when using dual X-ray absorptiometry and quantitative computed tomography both in vitro and in vivo. Using these two techniques, we found that the T-score densitometric index values were discrepant in the BMD qualitative evaluation, which can affect the diagnosis of osteopenia or osteoporosis, thus we propose its modification.

Absorptiometry, Photon↗

DXA vs QCT for subclinical celiac disease patients.

It has been recognized that celiac disease (CD) may be associated with osteoporosis. However, few data exist regarding bone disorders in adult patients with subclinical CD (SCD) and the best densitometric technique for assessing bone mineral density (BMD). We compared dual X-ray absorptiometry (DXA) and quantitative computed tomography (QCT) in measuring the lumbar spine of 23 female patients with SCD and 19 healthy subjects. There were lower densitometric values in the subjects with SCD than the control group. We found discordance between DXA and QCT results using World Health Organization (WHO) criteria with the T score. With QCT as the reference method for its sensitivity, we found one false-negative, two false-positive and two misdiagnosed cases. We suggest some correction factors to improve DXA evaluation and screening of bone loss in CD.

Absorptiometry, Photon↗

Densitometric evaluation in women with anorexia nervosa.

Anorexia nervosa (AN) is classified as a high-risk factor for osteoporotic fractures. Dual X-ray absorptiometry (DXA) is the most popular method for measuring bone loss, but it is less sensitive than quantitative computed tomography (QCT). We compared DXA and QCT in measuring the lumbar spine of 17 female patients with AN and 27 healthy subjects. We found discordance between DXA and QCT using World Health Organization (WHO) criteria with the T-score. With QCT as a reference method because of its sensitivity, we found one false-negative, one false-positive, and two misdiagnosed cases. We suggest some correction factors to improve DXA evaluation and screening of bone loss in AN.

Absorptiometry, Photon↗

Imaging the ankle and foot and using magnetic resonance imaging.

Magnetic resonance (MR) imaging has improved the possibility of evaluating musculoskeletal structures thus gaining an important role in the diagnosis and treatment of foot and ankle pathologies. In this review, the normal and pathological images of the ankle and foot obtained using MR techniques are presented and discussed. The high soft-tissue contrast resolution and the multiplanar sections of MRI allow the imaging of contiguous tissues where small contrast differences exist, such as ligamentous and tendinous injuries or impingement syndromes. The spatial resolution with high sensitivity for bone signal changes offers an early detection of osseous abnormalities such as stress fractures or osteonecrosis. Here it is specified possibilities and limitations of MRI in the diabetic foot: this technique is superior to nuclear medicine and computed tomography (CT), however it is unable to distinguish between neuro arthropathy and infection.

Journal Article↗

Vertebroplasty and kyphoplasty: new equipment for malignant vertebral fractures treatment.

The Purpose of our study was to assess the effectiveness and safety of Percutaneous Vertebroplasty and Kyphoplasty, in the treatment of pain deriving from neoplastic vertebral compression fractures (VCF). We treated with these new techniques oncologic patients with unremitting pain over spine, refractory to the conventional medical therapy (analgesics, bed-rest, bracing and bisphosphonates), elicited by pressure over spinous process and in absence of neurological signs. Both methods demonstrated a swift pain relief associated with an evident augmentation in vertebral body resistance. Nevertheless only Kyphoplasty revealed itself able to restorate the original somatic morphology and to diminish the spinal kyphosis. Polymethylmethacrylate's leakages (PMMA) not observed in the Kyphoplasty, instead have been found in the Vertebroplasty localized in the intersomatic or perispinal areas. Neither confirmation of epidural or foraminal extravasations, nor complications which pulmonary embolism for the involvement of venous plexus or connected to phenomenon of infection having to do with the procedures. Kyphoplasty and Vertebroplasty are effective alternatives, simple and safe in the treatment of vertebral collapses consequent to aggressive haemangiomas, myelomas and metastases. This entails a complete relief of symptoms and restoration of mobility in 90% of patients within 24 hours from the procedure.

Bone Cements↗

Enhanced contact activity of fluconazole in association with antioxidants against fluconazole-resistant organisms.

Fluconazole alone does not demonstrate any contact activity against resistant organisms. Phenolic antioxidants, such as butylated hydroxyanisole, appear to promote fluconazole activity resulting in the killing of 10(4) cfu/mL of 11 resistant Candida albicans strains within 3-15 min and of 10(4) cfu/mL of 10 resistant Escherichia coli strains within 6-15 min. Fluconazole activity was increased by the addition of ethyl alcohol (20%). Antioxidants appear to promote fluconazole activity by increasing cell membrane permeability. This combination has potential advantages in the administration of topical fluconazole.

Antioxidants↗

CT-guided injection of botulinic toxin for percutaneous therapy of piriformis muscle syndrome with preliminary MRI results about denervative process.

Piriformis muscle syndrome (PMS) is a cause of sciatica, leg or buttock pain and disability. The pain is usually increased by muscular contraction, palpation or prolonged sitting. The aim of our paper was to evaluate the feasibility of CT-guided percutaneous botulinic toxin (BTX) injection for the purpose of PMS treatment. Thirty patients suffering from PMS, suspected with clinical and electrophysiological criteria, after imaging examinations excluding other causes of sciatic pain, resulted positive at the lidocaine test and were treated by intramuscular injection of BTX type A under CT guidance. The follow-up (12 months) was performed with clinical examination in all cases and with MR 3 months after the procedure in 9 patients to evaluate the denervative process entity of the treated muscle. In 26 cases relief of symptoms was obtained after 5-7 days. In 4 patients an insufficient relief of pain justified a second percutaneous treatment which was clinically successful. No complications or side effects were recorded after BTX injection. The MR examination showed a signal intensity change of the treated muscle in 7 patients due to the denervative process of PM, whereas in the remaining 2 cases only an atrophy of the treated muscle was detected. Larger series are necessary to confirm these MRI preliminary results. The CT-guided BTX injection in the PMS is an emergent and feasible technique that obtains an excellent local therapeutic effect without risk of imprecise inoculation.

Adult↗

"Relapsing-remitting" bilateral synovial cysts of the lumbar spine. A case report.

A case of bilateral synovial cysts is reported. They were shown by MRI first on one side and later, on the contralateral side, concomitantly with a reduction in the size of the cyst. Because spine instability was also present the most acceptable assumption is that there may be a contiguity between the articular facets and the cysts, thus enabling the filling and emptying of the cysts itself.

Humans↗

Contact imidazole activity against resistant bacteria and fungi.

The activities of miconazole and miconazole sulphosalicylate were evaluated by a contact test using strains of Enterococcus faecalis and Escherichia coli and Candida spp selected for their resistance. The results showed that killing of the organisms occurred within a few minutes. Imidazole activity required a medium of low electrical conductivity and a pH of 5.6. Greater sensitivity could be obtained with pretreatment of the microbial suspensions with sodium dioctylsulphosuccinate. Microorganisms tested in culture media with low electrical conductivity and at pH 5.6 showed enhanced sensitivity to azoles with MIC values about 20-30 times lower than those obtained using control media. Practical implications of the use of topical drugs are discussed.

Antifungal Agents↗

[Virtual laryngoscopy of neoplastic pharyngeal and laryngeal pathology].

PURPOSE: This study investigated the feasibility and clinical value of high-resolution virtual laryngoscopy (VL) based on helical CT data sets. MATERIAL AND METHODS: Fifteen patients with neoplastic laryngeal pathology underwent helical CT examination performed with controlled breath. The CT data were downloaded to a workstation equipped with software for three-dimensional rendering (Silicon Graphics O2, Vitrea Visualization 1.2.8). Two radiologists using Fly Through software generated both antegrade and retrograde endoluminal virtual endoscopy navigations of the larynx. The results of the radiological study were compared with conventional endoscopy findings. RESULTS AND CONCLUSIONS: Virtual laryngoscopy provided the correct diagnosis in 13 of 15 cases. VL is capable of simulating the visual findings of endoscopy in cases of laryngeal tumors and subglottic stenosis. Small and plane tumors of the vocal chords are not adequately visualized. This technique appears to be useful both as biopsy guide during conventional laryngoscopy and as a correct pre-surgery staging, particularly in stenotic tumors.

Humans↗

[Embolization of the uterine artery in the treatment of uterine myoma].

PURPOSE: To propose uterine myoma embolization as an alternative to myomectomy or hysterectomy in the treatment of symptomatic myomas; to evaluate the efficacy of the procedure in terms of clinical outcome, adopting all procedural and technical precautions to ensure minimal X-ray exposure and preserve reproductive potential. MATERIAL AND METHODS: Between April 1998 and February 2000, 26 patients, age range 32-54 years (mean 41 years), underwent uterine arterial embolization for menorrhagia, pelvic pain, and sensation of mass and pressure. Inclusion criteria were: single myomas, intramural localization and rich vascolarization of the lesion. Dose to patient was obtained by placing a thermoluminescent dosimeter (Harshaw, Solon, Ohio) both placed in posterior fornix of the vagina and on the skin at the beam entrance site. The procedure was performed under peridural anesthesia; polyvinil alcohol particles 355-500 mu (Contour) (Target Therapeutics, Boston Scientific Corporation, Fremont CA, USA) were employed as embolic agent. The uterine arteries were incannulated with a 5F (Glidecath, Terumo, Europe NV, Belgium) and successively 3F coaxial microcatheter (Target, Boston Scientific Corporation, Fremont CA, USA); the embolic material was injected as distally as possible. Color Power Doppler Ultrasound follow-up before and after i.v. contrast media administration (Levovist SHU 508 A, Shering, Berlin, Germany) was carried out at 15 days, at 1, at 3, at 6 months, and at 1 year from embolization. Pre-procedural evaluation and follow-up at 1 year was performed by MRI using T1 and T2 weighted images before and after Gadolinium (GdDTPA Shering, Berlin, Germany) administration. RESULTS: The technical success of the interventional procedure was 100% (26/26 cases). The mean fluoroscopy time was 20 minutes, and the mean number of angiographic exposures was 10. The mean estimated ovarian dose was 18.75 cGy and the mean adsorbed skin dose was 126.71 cGy. The imaging follow-up showed a 55% reduction of myoma volume at 6 months and a 75% reduction at 1 year. All patients reported a marked decrease in symptoms. No major complications were observed. The appearance of pelvic pain in the 24-48 hours after the procedure required sedation by analgesic pump; transitorial amenorrhea was observed in 3 patients. As for term complications, 2 patients have eliminated necrotic material through the vagina four weeks after procedure. The patients reported great satisfaction with the procedure. DISCUSSION: Many treatment options are currently available for symptomatic uterine myomas. One is surgical myomectomy which is associated with increased blood loss, pain and post operative morbidity and requires an additional surgical procedure for fibroma recurrence in 20-25% of patients. Another alternative treatment is hormonal therapy, which drammatically improves symptoms and reduces fibroid size although leiomyomas regrow to their original size within a few months of discontinuing treatment. Uterine embolization is a relatively new treatment for uterine fibroids that can be considered as an alternative to surgical and medical procedures. The radiation exposure adsorbed by the patient is reduced by using pulsed fluoroscopy and taking all the precautionary measures required to minimize the dose. CONCLUSIONS: The technical success, the patient' satisfation, the short hospitalization time and preservation of fertility confer to uterine artery embolization the role of a new alternative therapy for the treatment of symptomatic uterine myomas.

Adult↗

[Magnetic resonance angiography with three-dimensional dynamic technique after contrast media administration for the study of the portal system ].

PURPOSE: To evaluate the feasibility of a contrast enhanced MR angiography (MRA) technique, using the latest 1.5 T MR tomoscan, to obtain optimal imaging of the portal system and compare the angiographic images with those obtained by color-Doppler and DSA. MATERIAL AND METHODS: Thirty patients (9 women and 21 men: average 53 years old) underwent contrast MRA of the portal vein, after portal hypertension had been diagnosed on the basis of clinical and chemical data and by color-Doppler. We used a dynamic 3D FFE T1-weighted breath - hold sequence during the arterial and venous phase after administering. 0.2 mmol/Kg of gadolinium-DTPA were at the rate of 2 ml/s. The contrast bolus was monitored using a 2D FFE T1-weighted sequence on a coronal plane. A FFE T1-weighted sequence was performed on axial plane before and after the dynamic sequence to obtain evaluate the a hepatic parenchyma. In the post processing phase MIP (maximum intensity projection) were reconstructed. We considered the patency of the portal venous system and the presence of cavernomatous and collateral circles; portal thrombosis was classified as partial or complete and as proximal or distal. RESULTS: Good quality MR angiographic images were obtained in 28 of the 30 cases examined; in 2 patients movement artefacts compromised the image quality. We observed a concordance between MRA and Doppler ultrasound in 79 vessels out of 84 (94%). A 97.5% concordance was found between MRA and DSA (82 vessels out of 84) with a sensitivity of 100% and a specificity of 97.3%. MRA was superior to DSA and Doppler ultrasound for evaluating large collateral shunts, above all gastro-esophageal and paraumbilical shunts, and complex anatomical conditions. CONCLUSIONS: Where available, advanced MRA technology with contrast enhancement should be used as a routine modality to study the anatomy and pathology and the portal system in all patients in whom Doppler ultrasound has yielded doubtful information. MRA is well-suited to obtain good vascular imaging before surgical or interventional procedures.

Adult↗