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1.
Radiol Case Rep ; 12(1): 54-58, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28228879

RESUMEN

Seminal vesicle cysts are a very rare condition and its often associated with ipsilateral renal agenesis. The diagnosis of seminal vesicle cysts may be delayed or missed because of the non-specific symptoms of this condition. This article reports a triad of right renal agenesis, ipsilateral seminal vesicle cyst, and ejaculatory duct obstruction (Zinner syndrome) in a 56 years old man.

2.
Clin Exp Obstet Gynecol ; 42(5): 705-7, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26524833

RESUMEN

The term "isthmocele" refers to a niche on the anterior wall of the uterine isthmus or of the cervical canal at the site of a previous cesarean delivery scar. Such anatomic defect can cause many gynecologic sequelae that only recently have being identified and described. Hysteroscopy is commonly considered the gold standard for the diagnosis and also for the treatment, at least in the case of defects of small size. The authors described the case of a 37-year-old woman who underwent a cesarean section (CS) seven years before, with a long lasting history of menstrual irregularities, and pelvic pain increasing during menstruation at the hypogastric level. Magnetic resonance imaging (MRI) showed an exceptionally large isthmocele on the anterior wall of a retroflexed uterus which was otherwise misinterpreted as the uterine cavity filled with menstrual blood during a previous hysteroscopy (HSC). Although exceptional, this case highlights the possibility that a large sized isthmocele in a retroflexed uterus could be misinterpreted as the uterine cavity filled by menstrual blood at HSC. In this case MRI definitely clarified the diagnosis.


Asunto(s)
Cesárea , Cicatriz/patología , Retroversión Uterina/diagnóstico , Adulto , Diagnóstico Diferencial , Femenino , Humanos , Histeroscopía , Imagen por Resonancia Magnética , Dolor Pélvico/etiología , Retroversión Uterina/complicaciones , Retroversión Uterina/patología
3.
Clin Exp Obstet Gynecol ; 42(6): 827-32, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26753498

RESUMEN

Uterine leiomyomas are the most common benign gynecological tumors affecting 20-30% of women in reproductive age. Despite their benignity, in some cases several symptoms may require surgical intervention. Submucosal leiomyomas are less frequent (5-10%), but are usually symptomatic. Approximately 2.5% of the myomas are pedunculated and can protrude in the cervical canal. Symptomatic leiomyomas can be treated either by hysterectomy or myomectomy, and these procedures can be performed with several techniques. Whenever possible, hysteroscopic myomectomy is better because it has many advantages, as it also preserves future fertility. Two interesting cases of prolapsed pedunculated submucous leiomyomas are reported in order to prove that magnetic resonance imaging (MRI) is essential to choose the most appropriate treatment and to perform an adequate presurgical planning, which must be based on an overall assessment of the leiomyoma's characteristics (number, location, size and presence or absence of a stalk) and the patient's characteristics.


Asunto(s)
Leiomioma/diagnóstico , Neoplasias Uterinas/diagnóstico , Adulto , Diagnóstico Diferencial , Femenino , Humanos , Leiomioma/patología , Leiomioma/cirugía , Imagen por Resonancia Magnética , Persona de Mediana Edad , Miomectomía Uterina , Neoplasias Uterinas/patología , Neoplasias Uterinas/cirugía
4.
Clin Radiol ; 68(11): e601-8, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23916550

RESUMEN

AIM: To evaluate the problems that may arise in breast magnetic resonance imaging (MRI) related to the presence of artefacts and pitfalls, in order to improve its accuracy, sensitivity, and specificity. MATERIALS AND METHODS: Six hundred and thirty breast MRI examinations performed using a 1.5 T magnet were analysed retrospectively. Each type of artefact that may have affected the correct interpretation of the acquired images was considered and analysed. In particular, the presence of technical artefacts, which are related to patient-dependent factors or to the examination itself, and non-technical artefacts, which are the result of inadequate and incorrect image interpretation occurring in absence of technical issues, were examined. In every case of suspicious findings, doubtful lesions were subjected to histological characterization for appropriate therapeutic planning. In the remainder of cases, patients underwent follow-up for at least 18 months. RESULTS: Artefacts were found in 33% of all examinations, among those 48.6% were caused by movement, 33.6% were due to non-homogeneous or failed fat saturation, 8.7% to incorrect positioning of the patient, 7.2% to metallic artefacts, 1.4% to aliasing, and 0.5% were "zebra artefacts". When the artefact was identified in a sequence, the sequence was performed a second time after corrective measures. No artefacts affected diagnostic interpretation of the obtained images. CONCLUSION: The present study provides a specific and precise review of the most frequent artefacts with a discussion of possible and practical solutions. A highly qualified team is required to perform accurate diagnostic tests and to limit or remove the possibility of misinterpretation.


Asunto(s)
Artefactos , Enfermedades de la Mama/diagnóstico , Mama/patología , Imagen por Resonancia Magnética/métodos , Adulto , Anciano , Anciano de 80 o más Años , Medios de Contraste , Femenino , Gadolinio DTPA , Humanos , Aumento de la Imagen/métodos , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad
5.
Clin Radiol ; 68(6): e293-300, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23541093

RESUMEN

AIM: To assess the feasibility of magnetic resonance defaecography (MRD) in pelvic floor disorders using an open tilting magnet with a 0.25 T static field and to compare the results obtained from the same patient both in supine and orthostatic positions. MATERIALS AND METHODS: From May 2010 to November 2011, 49 symptomatic female subjects (mean age 43.5 years) were enrolled. All the patients underwent MRD in the supine and orthostatic positions using three-dimensional (3D) hybrid contrast-enhanced (HYCE) sequences and dynamic gradient echo (GE) T1-weighted sequences. All the patients underwent conventional defaecography (CD) to correlate both results. Two radiologists evaluated the examinations; inter and intra-observer concordance was measured. The results obtained in the two positions were compared between them and with CD. RESULTS: The comparison between CD and MRD found statistically significant differences in the evaluation of anterior and posterior rectocoele during defaecation in both positions and of rectal prolapse under the pubo-coccygeal line (PCL) during evacuation, only in the supine position (versus MRD orthostatic: rectal prolapse p < 0.0001; anterior rectocoele p < 0.001; posterior rectocoele p = 0.008; versus CD: rectal prolapse p < 0.0001; anterior rectocoele p < 0.001; posterior rectocoele p = 0.01). The value of intra-observer intra-class correlation coefficient (ICC) ranged from good to excellent; the interobserver ICC from moderate to excellent. CONCLUSION: MRD is feasible with an open low-field tilting magnet, and it is more accurate in the orthostatic position than in the supine position to evaluate pelvic floor disorders.


Asunto(s)
Defecografía/métodos , Imagen por Resonancia Magnética/métodos , Trastornos del Suelo Pélvico/patología , Adulto , Anciano , Estreñimiento/diagnóstico , Estreñimiento/patología , Defecación , Incontinencia Fecal/diagnóstico , Incontinencia Fecal/patología , Femenino , Humanos , Persona de Mediana Edad , Diafragma Pélvico/patología , Trastornos del Suelo Pélvico/diagnóstico , Postura , Posición Supina , Adulto Joven
6.
Eur J Radiol ; 81(11): 3178-84, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22417393

RESUMEN

OBJECTIVE: To asses the value of second-look ultrasound (US) for identifying BIRADS 3 (Breast Imaging Reporting Data System) mammary lesions detected by breast Magnetic Resonance imaging (MRI). MATERIALS AND METHODS: From April 2008 to May 2009 330 breast MRI were performed of which 60 patients are classified as BIRADS 3. 84 lesions underwent second-look US and percutaneous vacuum biopsy Vacora system US-guided. STATISTICAL ANALYSIS: lesions were stratified into two groups: visible on US (Group 1) and not visible on US (Group 2). The clinical impact of second-look US was studied in terms of negative predictive value (NPV). RESULTS: The positive predictive value (PPV) of category 3 BIRADS MRI was found to be 89%. Second look-US results detected lesions in 51% of the MRI enhancing lesions. The second look-US showed a NPV of 97%. The NPV of second look-US was significantly greater than the NPV of MRI BIRADS 3 (97% vs 89%, p<0.05). The logistic regression analysis showed a higher number of malignant lesions in group 1 than in group 2 (7vs 2, OR 3.7, p<0.05). CONCLUSIONS: The second-look US permitted the correct management of subcentimetric MRI BIRADS 3 lesions not visible with conventional imaging tecniques.


Asunto(s)
Algoritmos , Neoplasias de la Mama/diagnóstico , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos , Reconocimiento de Normas Patrones Automatizadas/métodos , Ultrasonografía Mamaria/métodos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Aumento de la Imagen/métodos , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
7.
Radiol Med ; 116(8): 1288-302, 2011 Dec.
Artículo en Inglés, Italiano | MEDLINE | ID: mdl-21892714

RESUMEN

PURPOSE: The objective of this preliminary study was to examine the effects of combined magnetic resonance/positron emission tomography (MR-PET) evaluation in the morphofunctional characterisation of ovarian lesions. MATERIALS AND METHODS: From June 2008 to September 2010, we evaluated 24 patients (mean age 44±10 years; range 24-74) with ovarian lesions incidentally detected on ultrasonography (US) and/or multislice computed tomography (CT). All patients underwent MR imaging of the pelvis and total-body CT-PET. PET and MR images were subsequently fused at postprocessing using specific anatomical criteria. Results were compared with the histological examination. RESULTS: Of the 24 examined lesions, 19 were malignant and five were benign on histological examination. MR, CT-PET and MR-PET sensitivity was 84%, 74% and 94%, respectively and specificity 60%, 80% and 100%, respectively. Positive (PPV) and negative predictive (NPV) values were 93% and 44% for CT-PET, 89% and 50% for MR and 100% and 83% for MR-PET, respectively. CONCLUSIONS: Pelvic MR-PET fusion imaging provides advantages in terms of sensitivity and especially specificity compared with MR imaging or CT-PET alone. The added value of this fusion imaging modality lies in combining the benefits of the morphological evaluation provided by MR imaging and the metabolic assessment provided by PET.


Asunto(s)
Enfermedades de los Anexos/diagnóstico , Imagen por Resonancia Magnética , Tomografía de Emisión de Positrones , Enfermedades de los Anexos/diagnóstico por imagen , Enfermedades de los Anexos/patología , Enfermedades de los Anexos/cirugía , Adulto , Anciano , Biopsia , Femenino , Fluorodesoxiglucosa F18 , Humanos , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Radiofármacos , Estudios Retrospectivos , Sensibilidad y Especificidad
8.
Radiol Med ; 116(4): 620-33, 2011 Jun.
Artículo en Inglés, Italiano | MEDLINE | ID: mdl-21424567

RESUMEN

PURPOSE: This study was undertaken to explore the capabilities of an open-configuration, low-field, tilting, magnetic resonance (MR) system for investigating pelvic floor disorders and to compare the results obtained with the patient in the semiorthostatic and supine positions. MATERIALS AND METHODS: Eighteen female patients with a diagnosis of pelvic floor disorder (physical examination and conventional defecography) underwent dynamic MR defecography (MRD) with a 0.25-T tilting MR system (G-scan, Esaote). Images were obtained after administration of contrast agent into the rectum, bladder and vagina in both the orthostatic and supine positions. Three-dimensional T2-weighted hybrid contrast-enhanced (HYCE) sequences and dynamic T1-weighted gradient echo (GE) sequences were acquired at rest, during maximal contraction of the anal sphincter, straining and defecation. RESULTS: Good image quality was obtained in 15/18 patients; three presented severe artefacts due to motion, and three had incontinence, which hampered the functional studies. Better anatomical detail was obtained with MRD compared with conventional defecography. Three prolapses were observed in the semiorthostatic position only, and seven were found to be more severe in the orthostatic than in the supine position. CONCLUSIONS: Dynamic MRD with an open-configuration, low-field, tilting MR system is a feasible and promising tool for studying the pelvic floor. Larger series are necessary to assess its real diagnostic value.


Asunto(s)
Defecación , Imagen por Resonancia Magnética/métodos , Prolapso de Órgano Pélvico/fisiopatología , Adulto , Anciano , Femenino , Humanos , Persona de Mediana Edad , Diafragma Pélvico/patología , Prolapso de Órgano Pélvico/diagnóstico , Rectocele/diagnóstico , Rectocele/fisiopatología , Adulto Joven
9.
Oral Implantol (Rome) ; 4(1-2): 14-22, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23285397

RESUMEN

TO CORRELATE DIFFERENT CT SYSTEM: MSCT (multislice computed tomography) with different acquisition parameters (100KV, 80KV), different reconstruction algorithm (ASIR) and CBCT (cone beam computed tomography) examination in terms of absorbed X-ray dose and diagnostic accuracy.80 KV protocols compared with 100 KV protocols resulted in reduced total radiation dose without relevant loss of diagnostic image information and quality. CBCT protocols compared with 80 KV MSCT protocols resulted in reduced total radiation dose but loss of diagnostic image information and quality although no so relevant.In addition the new system applies to equipment ASIR applicable on MSCT allows 50% of the dose without compromising image quality.

10.
Oral Implantol (Rome) ; 3(3): 2-10, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23285385

RESUMEN

AIM: The aim of the study is to evaluate the incidence of different expansive lesions and the advantages of the clinical employment of Dentalscan to study bones lesions and to establish a common diagnostic path. MATERIALS AND METHODS: Since January 2005 to November 2009, 3200 patients, not selected for sex or age, have undergone a CT "Dentalscan" in the department of Diagnostic Imaging, Tor Vergata University Hospital (PTV), a suspect bone pathology was found in 704 of them through the XR-orthopantomograpy (OPT). CT images were obtained with General Electric CT Light Speed multislice. Images were saved in the Advantage Workstation (GE) supported by the "Dentascan" dedicated software and by the 3D software (3D SSD). The protocol was : Slice thickness 1,25 mm, gap 0, matrix 512 × 512, 140 KV and 70 mA. All the lesions were also studied with the dedicated three-dimensional reconstructor 3D SSD. Biopsy for diagnosis was performed on all the lesions, except one (false positive with digital OPT). THE TECHNIQUE SENSITIVITY WAS ASSESSED FOR TWO IMPORTANT CLASSES: benign and malignant lesions. RESULTS: Through CT Dentascan a detailed evaluation of the jaws lesions and their extension was obtained. 656 patients (93.1 %) out of 704 examined for a suspicious lesion on the orthopantomography had a benign lesion: (127 follicular cysts (18.2 %), 181 radicular cysts (25.1%), 93 non odontogenic cysts (13.2%), 29 fibroma (4.2%), 198 odontomes (28.2%), 24 ameloblastoma (3.6%), 4 brown tumors (0.7%), 47 (6.9%) had malignant lesions: (12 carcinoma (1.7%), 29 metastasis (4.3%), 6 sarcoma (0.8%), 1 Dentascan CT resulted to be negative (1 false positive of digital OPT). The sensitivity of the technique for both groups was 99% for benign lesions and 98% for malign lesions. CONCLUSIONS: CT Dentascan characteristics suggest to consider these techniques as the gold standard for the evaluation of jaw expansive lesions and the support of surgical planning.

11.
Cancer Biomark ; 5(4): 167-75, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19729826

RESUMEN

CEA and CA19.9 are biomarkers routinely measured for monitoring treatment response in metastatic colorectal cancer (MCRC) patients, yet their predictive value during therapies containing new antineoplastic drugs (i.e. FOLFIRI/OLFOX/Bevacizumab) has not yet been investigated. Consecutive chemotherapy-naive MCRC patients treated with either standard chemotherapy-alone (FOLFIRI/FOLFOX) or chemotherapy+bevacizumab (FOLFIRI+bevacizumab) were included in the analysis. Patients had to have serial biweekly measurement of CEA and CA19.9 available for at least three months of treatment. Primary study endpoint was Progression Free Survival (PFS). Biomarker levels and type of treatment as well as major demographic and clinical factors were analyzed for their impact on PFS. Out of 243 evaluated MCRC patients, 87 had biomarkers available as per inclusion criteria. Among all evaluated factors only type of treatment (chemotherapy-alone vs chemotherapy+bevacizumab) and baseline CA19.9 (> vs < normal) were independently associated with PFS, whilst neither baseline CEA nor biomarker reduction during therapy reached statistical significance. When patients with different baseline CA19.9 levels were analysed separately, only patients with abnormal CA19.9 benefited significantly from the administration of bevacizumab.The current study demonstrated a significant predictive value of CA19.9, but not of CEA and biomarker reduction, for MCRC patients treated with new antineoplastic drugs. Moreover, only patients with abnormal baseline CA19.9 levels benefited significantly from bevacizumab.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Biomarcadores de Tumor/análisis , Antígeno CA-19-9/análisis , Antígeno Carcinoembrionario/análisis , Neoplasias Colorrectales/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Inhibidores de la Angiogénesis/uso terapéutico , Anticuerpos Monoclonales Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Bevacizumab , Camptotecina/análogos & derivados , Camptotecina/uso terapéutico , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/secundario , Supervivencia sin Enfermedad , Femenino , Fluorouracilo/uso terapéutico , Humanos , Leucovorina/uso terapéutico , Masculino , Persona de Mediana Edad , Compuestos Organoplatinos/uso terapéutico , Valor Predictivo de las Pruebas
12.
Radiol Med ; 113(6): 830-40, 2008 Sep.
Artículo en Inglés, Italiano | MEDLINE | ID: mdl-18633687

RESUMEN

PURPOSE: The aim of this study was to evaluate a handheld vacuum-assisted device for magnetic resonance imaging (MRI)-guided breast biopsy. MATERIALS AND METHODS: In 47 patients, a total of 47 suspicious breast lesions (mean maximum diameter 9 mm) seen with MRI (no suspicious changes on breast ultrasound or mammography) were sampled using a 10-gauge vacuum-assisted breast biopsy (VAB) device under MRI guidance. Histology of biopsy specimens was compared with final histology after surgery or with follow-up in benign lesions. RESULTS: Technical success was achieved in all biopsies. Histological results from VAB revealed malignancy in 15 lesions (32%), atypical ductal hyperplasia in four lesions (8%) and benign findings in 28 lesions (60%). One of four lesions with atypical ductal hyperplasia was upgraded to ductal carcinoma in situ after surgery. One of seven lesions showing ductal carcinoma was upgraded to invasive carcinoma after surgery. Two lesions diagnosed as infiltrating carcinoma by VAB were not validated at excisional biopsy due to complete removal of the lesion during the procedure. During the follow-up (mean 18 months) of histologically benign lesions, we observed no cases of breast cancer development. Because of morphological changes on follow-up MRI scans, two lesions underwent surgical excision, which confirmed their benign nature. Besides minor complications (massive bleeding, n = 1) requiring no further therapeutic intervention, no complications occurred. CONCLUSIONS: MRI-guided biopsy of breast lesions using a handheld vacuum-assisted device is a safe and effective method for the workup of suspicious lesions seen on breast MRI alone.


Asunto(s)
Biopsia con Aguja/instrumentación , Enfermedades de la Mama/patología , Neoplasias de la Mama/patología , Mama/patología , Imagen por Resonancia Magnética/métodos , Adulto , Anciano , Biopsia con Aguja/métodos , Medios de Contraste , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Gadolinio DTPA , Humanos , Imagen por Resonancia Magnética/instrumentación , Persona de Mediana Edad , Factores de Tiempo , Vacio
13.
Eur J Paediatr Dent ; 9(2): 65-70, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18605887

RESUMEN

AIM: This was to correlate the dosimetric evaluation with high diagnostic accuracy by suggesting a protocol that significantly reduces the dose administered by a Dentascan exam without affecting diagnostic accuracy. MATERIALS AND METHODS: 17 patients were selected consecutively (7 males and 10 females) of a mean age of 11.2 (8-14 years) who sought orthodontic treatment. They needed CT control before and after treatment with RME to evaluate impacted canines. The study was performed using a multidetector 16-rows CT with two protocols that provided 2 different KV acquisition parameters: 80 KV or 120 KV. Radiation dose was evaluated in two ways: CTDI and DLP. Image quality was rated and the results were compared to identify significant differences in terms of image quality, radiation exposure and presence of artefacts. RESULTS: The 80 KV scanning has a significantly lower effective radiation dose compared to the 120 KV scanning (p <0.05). The images of all patients were used for comparing the protocols in terms of image quality. The mean scores for the 80 KV scanning images were 4.18 +/-0.81 and 4.41 +/-0.80 for dose obtained by 120 KV scanning. The median image quality was 4 (good) for both protocols. The 80 KV protocol allowed, as well as the 120 KV, a careful analysis by the orthodontist and the dental surgeon that together, based on this images, can choose the best line of treatment between several available options. CONCLUSION: 80 KV protocols compared with 120 KV protocols resulted in reduced total radiation dose without relevant loss of diagnostic image information and quality. The images were good enough to obtain information about the exact position of impacted teeth and to plan the best line of surgical treatment and mechanotherapy strategy.


Asunto(s)
Maloclusión/diagnóstico por imagen , Radiografía Dental Digital/métodos , Tomografía Computarizada por Rayos X/métodos , Diente Impactado/diagnóstico por imagen , Adolescente , Niño , Diente Canino/diagnóstico por imagen , Femenino , Humanos , Masculino , Maxilar , Dosis de Radiación , Estadísticas no Paramétricas , Tomógrafos Computarizados por Rayos X , Tomografía Computarizada por Rayos X/instrumentación
14.
Oral Implantol (Rome) ; 1(2): 56-65, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23285338

RESUMEN

The aim of this study is to describe the current role of imaging in pre-surgical planning, reporting 25 cases of paranasal sinus tumors examined in our Institute. Between June 2006 and May 2008, we identified 25 patients with malignant tumors of the paranasal sinuses. All of the patients were evaluated with CT and/or MR exams. US were used to assess regional lymph node involvement. When necessary CT-PET scanning using FDG, was done. Diagnostic imaging is essential during the initial work-up of a patient suspected of having a paranasal sinus tumor. The role of imaging is to define the tumor extension, nodal involvement, metastases and recurrences in the postoperative patient. CT and MR imaging are the primary modalities employed; each have advantages and disadvantages but tend to be complementary. The involvement of fine bone structures is best evaluated with CT. In assessing the extent of the tumor, MR provides excellent soft tissue detail, allowing for delineation of neoplasm from surrounding inflammatory tissue and secretions. For evaluation of lymph node enlargement color-Doppler US, CT and MR provide morphologic data, while CT-PET provides metabolic data. CT-PET can be used to stage nodal and metastatic disease and for assessing the efficacy of therapy or recurrent disease.

15.
Radiol Med ; 111(1): 130-8, 2006 Feb.
Artículo en Inglés, Italiano | MEDLINE | ID: mdl-16623313

RESUMEN

PURPOSE: The development of new operative techniques in oral and maxillofacial surgery within the last few years has led to an increasing demand for Dentascan examination, also in paediatric patients. It is necessary to modify acquisition parameters to reduce the absorbed dose. The aim of this study was to define a Dentascan protocol in which a reduced X-ray dose could be used. MATERIALS AND METHODS: Dosimeters were applied to the eyes, mouth, parotid glands, thyroid and back of the neck of an anthropomorphic Plexiglas phantom that underwent multidetector computed tomography (MDCT) Dentascan examinations. Both 120kV and 80 kV were used to study the mandibular and maxillary arches. RESULTS: Examinations obtained with the 80 kV protocol showed a ten-fold reduction in the absorbed dose, without affecting image quality. CONCLUSIONS: We suggest a Dentascan protocol that reduces the X-ray dose administered to the patient while ensuring the same high diagnostic accuracy.


Asunto(s)
Cabeza/efectos de la radiación , Maxilares/diagnóstico por imagen , Radiografía Dental , Programas Informáticos , Tomografía Computarizada por Rayos X , Humanos , Maxilares/efectos de la radiación , Procedimientos Quirúrgicos Orales , Fantasmas de Imagen , Dosis de Radiación
17.
Radiol Med ; 98(4): 275-82, 1999 Oct.
Artículo en Italiano | MEDLINE | ID: mdl-10615367

RESUMEN

PURPOSE: To investigate different clinical applications of gadolinium-enhanced MR angiography (Gd MRA) using three-dimensional breath-hold GE sequences, without bolus time calculation, in patients with vascular diseases. MATERIAL AND METHODS: Forty-seven patients were examined (49 studies in all). Eleven of them had an abdominal aortic aneurysm, 6 surgical bypass, 7 renal artery stenosis, 3 aortoiliac Wallstent, 7 aortic stent-graft; 11 patients had a suspected condition in the thoracic aorta and pulmonary arteries, 1 had subclavian artery stenosis and 1 suspected axillary artery compression. All patients were submitted to breath-hold Gd MRA, after 30-40 mL Gd, with a 1.5 T magnet (Gyroscan ACS-NT, Philips, The Netherlands) and a standard body coil. The GE sequences were acquired with TR = 8.8, TE = 2.7, FA = 60 degrees, matrix = 163 x 512, with 28 seconds acquisition time. Digital subtraction angiography and intraoperative findings were the reference standards to evaluate the results. RESULTS: Thoracopulmonary district: metastatic compression of axillary vessels was found in 1 breast cancer patient; the true and the false lumens and the intimal flap were identified in 2 patients with chronic aortic dissection (Stanford A), and graft patency and complete resolution of the aortic dissection was seen in the patient operated on for acute aortic dissection (Stanford A). The thrombus, lumen, extent and diameter were studied in 2 patients with thoracic aortic aneurysms. Subclavian artery stenosis was demonstrated in 1 patient, which was treated with transluminal angioplasty and stenting. The other 6 patients had normal findings. Abdominal aortic aneurysms (AAA): as for disease extent, breath-hold Gd MRA had 100% sensitivity and specificity compared with surgical findings. Juxtarenal aneurysm extent, which had been missed at DSA, was detected in 1 patient and then confirmed at surgery. Stenosis: comparing DSA and MRA findings in the whole series of patients we had 97.4% agreement (155/159 arteries), that is 76.4% (13/17) arteries) considering only stenoses > 50%. Breath-hold Gd MRA sensitivity and specificity were 100 and 87.5%, respectively, in our 28 stenoses. Bypass, aortoiliac stent, vascular endograft: patency was demonstrated in all the 6 surgical bypass patients, and there was agreement with color Doppler findings in 5 of 6. Breath-hold Gd MRA seems to have no possible applications in the follow-up of percutaneously implanted iliac stents, but we had excellent findings about patency and position of nichel-titanium endografts used for AAA treatment. CONCLUSIONS: We optimized breath-hold 3D MRA without bolus transit time calculation and with high-dose Gd in different clinical vascular conditions. In our opinion, 3D GE sequences can replace DSA in selected cases, providing a fast, accurate and noninvasive examination.


Asunto(s)
Enfermedades de la Aorta/diagnóstico , Arteriopatías Oclusivas/diagnóstico , Angiografía por Resonancia Magnética/métodos , Abdomen/irrigación sanguínea , Gadolinio , Humanos , Sensibilidad y Especificidad , Tórax/irrigación sanguínea
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