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1.
BMC Endocr Disord ; 22(1): 102, 2022 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-35428234

RESUMEN

BACKGROUND : Fine needle aspiration (FNA) cytology is the preferred method for assessing thyroid nodules for malignancy. Concern remains about the rate of false negative results. The primary aim of this study is to investigate the malignancy rate of thyroid nodules initially classified as benign (Thy 2). METHODS: We retrospectively examined 658 nodules in 653 (429 female) patients between January 2013 to December 2017. All FNA biopsies (FNABs) were performed under ultrasound (US) guidance by a radiologist with expertise in thyroid pathology. Nodules were cytologically classified according to the UK Royal College of Pathologists guidelines. Decisions about further management were made at a regular thyroid multidisciplinary meeting. Follow up of the Thy 2 nodules was determined based on clinical and radiological criteria. RESULTS: The mean age (± SD) was 53.2 (14.6) years. Five hundred out of 658 (76.0%) nodules were classified as Thy 2 (benign) after the first FNAB. Of these thyroid nodules initially classified as benign, 208 (41.6%) underwent repeat FNAB and 9 (1.8%) were surgically removed without repeat FNAB. The remainder were followed up clinically and/or radiologically. Seven (1.4%) of nodules initially classified as Thy 2 were later shown to be or to harbor malignancy after a follow-up of 74.5 (± 19.7) months. Papillary thyroid microcarcinomas were found co-incidentally in two thyroid glands of benign nodules, giving a true prevalence of 5/500 (1.0%). CONCLUSIONS: With a well targeted FNAB, the false negative rate of an initial benign thyroid FNA is very low thus routine second FNAB is not required in patients with a thyroid nodule initially deemed benign. Multidisciplinary input is imperative in informing decision making.


Asunto(s)
Neoplasias de la Tiroides , Nódulo Tiroideo , Biopsia con Aguja Fina/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Neoplasias de la Tiroides/diagnóstico por imagen , Neoplasias de la Tiroides/epidemiología , Nódulo Tiroideo/diagnóstico por imagen , Nódulo Tiroideo/epidemiología
2.
J Med Imaging Radiat Oncol ; 66(6): 761-767, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34845851

RESUMEN

INTRODUCTION: There are few existing severity scoring systems in the literature, and no formally widely accepted chest X-ray template for reporting COVID-19 infection. We aimed to modify the chest X-ray COVID-19 severity scoring system from the Brixia scoring system with placement of more emphasis on consolidation and to assess if the scoring tool could help predict intubation. METHODS: A severity chest X-ray scoring system was modified from the Brixia scoring system. PCR positive COVID-19 positive patient's chest X-rays admitted to our hospital over 3 months were reviewed and correlated with; non-invasive ventilation, intubation and death. An analysis was performed using a receiver operating curve to predict intubation from all admission chest X-rays. RESULTS: The median score of all 325 admission chest X-rays was 3 (Interquartile range (IQR) 0-6.5). The median score of admission chest X-rays of those who did not require ICU admission and survived was 1.5 (IQR 0-5); and 9 (IQR 4.75-12) was median admission score of those requiring intubation. The median scores of the pre-intubation ICU chest X-rays was 11.5 (IQR 9-14.125), this increased from a median admission chest X-ray score for this group of 9 (P-value < 0.01). A cut-off score of 6 had a sensitivity of 77% and specificity of 73% in predicting the need for intubation. CONCLUSION: Higher chest X-ray severity scores are associated with intubation, need for non-invasive ventilation and death. This tool may also be helpful in predicting intubation.


Asunto(s)
COVID-19 , Ventilación no Invasiva , Humanos , Intubación Intratraqueal , Estudios Retrospectivos , SARS-CoV-2 , Rayos X
3.
J Med Imaging Radiat Oncol ; 66(3): 345-350, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34415112

RESUMEN

INTRODUCTION: Unintentional weight loss is an important clinical problem. The role of CT is not firmly established in the workup of these patients. The aim of this study is to determine the diagnostic yield of CT Thorax, Abdomen and Pelvis (CT TAP) in patients with unexplained weight loss and to determine whether clinical or laboratory variables are associated with positive CT findings. METHODS: A retrospective review was performed of CT TAP examinations over 12 months with weight loss as an indication. Patients' electronic records and radiology reports were reviewed. Clinical and laboratory variables were assessed for correlation with positive findings on CT. RESULTS: 461 CT TAP studies with weight loss as the primary indication were identified. 124 were excluded; 82 due to a recent history of malignancy, 41 because CT TAP was used for staging of a new malignancy and one study was incomplete. This left 337 eligible examinations. 217 studies had findings of no clinical relevance, 50 studies were normal, 40 studies identified a possible cause of weight loss and 30 studies identified a definite cause. Of the 40 where a possible cause was identified, further work up led to a diagnosis which explained the weight loss in 13 patients. The diagnostic yield of CT TAP was 12.8%. Age, abdominal symptoms, degree of weight loss, anaemia, tumour markers and LDH did not significantly correlate with positive findings on CT. CONCLUSION: CT TAP is a helpful investigation in patients with unexplained weight loss with a diagnostic yield of 12.8%.


Asunto(s)
Abdomen , Pelvis , Abdomen/diagnóstico por imagen , Humanos , Pelvis/diagnóstico por imagen , Estudios Retrospectivos , Tórax , Tomografía Computarizada por Rayos X , Pérdida de Peso
4.
Ann Surg ; 274(2): 240-247, 2021 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-33534226

RESUMEN

OBJECTIVE: Evaluate the efficacy and quality of life associated with conservative treatment of acute uncomplicated appendicitis. SUMMARY BACKGROUND DATA: Conservative management with antibiotics only has emerged as a potential treatment option for acute uncomplicated appendicitis. However the reported failure rates are highly variable and there is a paucity of data in relation to quality of life. METHODS: Symptomatic patients with radiological evidence of acute, uncomplicated appendicitis were randomized to either intravenous antibiotics only or undergo appendectomy. RESULTS: One hundred eighty-six patients underwent randomization. In the antibiotic-only group, 23 patients (25.3%) experienced a recurrence within 1 year following randomization. There was a significantly better EQ-VAS quality of life score in the surgery group compared with the antibiotic-only group at 3 months (94.3 vs 91.0, P < 0.001) and 12 months postintervention (94.5 vs 90.4, P < 0.001). The EQ-5D-3L quality-of-life score was significantly higher in the surgery group indicating a better quality of life (0.976 vs 0.888, P < 0.001). The accumulated 12-month sickness days was 3.6 days shorter for the antibiotics only group (5.3 vs 8.9 days; P < 0.01). The mean length of stay in both groups was not significantly different (2.3 vs 2.8 days, P = 0.13). The mean total cost in the surgery group was significantly higher than antibiotics only group (€4,816 vs €3,077, P < 0.001). CONCLUSIONS: Patients with acute, uncomplicated appendicitis treated with antibiotics only experience high recurrence rates and an inferior quality of life. Surgery should remain the mainstay of treatment for this commonly encountered acute surgical condition.


Asunto(s)
Antibacterianos/uso terapéutico , Apendicitis/tratamiento farmacológico , Calidad de Vida , Adolescente , Adulto , Anciano , Apendicectomía , Apendicitis/cirugía , Femenino , Humanos , Irlanda , Masculino , Persona de Mediana Edad , Recurrencia
5.
Eur Radiol ; 30(12): 6508-6516, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32613286

RESUMEN

OBJECTIVES: Same-day CT colonography (CTC) following incomplete optical colonoscopy allows patients to avoid both a delayed diagnosis and the need for repeat bowel preparation. The aim of our study is to establish the diagnostic quality of same-day CT colonography following an incomplete optical colonoscopy. METHODS: We performed a retrospective review of patients undergoing same-day CT colonography following an incomplete colonoscopy at our center between July 2015 and December 2017 (N = 245). We divided the large bowel into thirteen subsegments in each patient. Using a semiquantitative scoring system, the quality of bowel preparation, adequacy of fecal tagging, and luminal distension were assessed in each subsegment on all views performed. A combined score for each subsection was obtained. RESULTS: Ninety-nine percent of studies did not require a repeat CTC or optical colonoscopy. Median values for bowel preparation and fecal tagging were satisfactory across the bowel segments for the cohort and luminal distension was acceptable in all but three patients. CONCLUSIONS: Same-day CTC should be considered in centers with capacity, following an incomplete optical colonoscopy. Same-day completion CTCs are of high diagnostic quality and this approach allows patients to avoid repeat bowel cleansing or a delayed diagnosis. KEY POINTS: • Same-day CT colonography is a high-quality examination that can be performed following incomplete optical colonoscopy. • Same-day CT colonography should be considered for patients with incomplete optical colonoscopy in centers with the capacity to offer this service. • Same-day CTC can avoid a delay in diagnosis and avoids repeat bowel preparation.


Asunto(s)
Colonografía Tomográfica Computarizada , Colonoscopía , Neoplasias Colorrectales/diagnóstico por imagen , Adulto , Anciano , Medios de Contraste , Heces , Femenino , Humanos , Pólipos Intestinales/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estudios Retrospectivos , Factores de Tiempo
6.
J Med Imaging Radiat Oncol ; 64(4): 484-489, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32441449

RESUMEN

BACKGROUND: Prospective renal donors are a select population of healthy individuals who have been thoroughly screened for significant comorbidities before they undergo multi-detector computed tomography angiography and urography (MDCT). PURPOSE: The aim of this study is to describe the anatomy of potential living renal donor subjects using MDCT over a 2-year period. The primary objective is to identify the renal arterial anatomy variations, with a secondary objective of identifying venous and collecting system/ureteric variations. MATERIALS AND METHODS: A prospective study was performed of prospective living kidney transplant donors at a national kidney transplant centre. Study inclusion criteria were all potential kidney donors who underwent MDCT during the living-donor assessment process over a 2-year period. RESULTS: Our cohort included 160 potential living donors who had MDCT; mean age was 45.6 years (range, 21-71). Two renal arteries were identified on the left in 40 subjects (25%) and on the right in 42 subjects (26.3%). A total of 3 or more renal arteries were identified on the left in 7 subjects (4.4%) and on the right in 7 subjects (4.4%). On the left, the distances between multiple arteries ranged from 1 mm to 43 mm, and on the right, they were 1 mm to 84 mm. CONCLUSIONS: Conventionally described anatomy was only seen on the left side in 70.6% and 69.4% on the right side of subjects. Single renal arteries are seen in 54.4% showing that conventional anatomy has a relatively low incidence.


Asunto(s)
Trasplante de Riñón , Donadores Vivos , Tomografía Computarizada Multidetector/métodos , Arteria Renal/anatomía & histología , Adulto , Anciano , Femenino , Humanos , Riñón/irrigación sanguínea , Riñón/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Arteria Renal/anomalías , Arteria Renal/diagnóstico por imagen , Adulto Joven
7.
Abdom Radiol (NY) ; 45(4): 1044-1048, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31123769

RESUMEN

PURPOSE: Routine low dose non-contrast CT of the abdomen and pelvis has been suggested prior to same day completion CT colonography (CTC) to assess for occult perforation at preceding incomplete colonoscopy, before further gaseous insufflation at CTC. The aim of our study is to examine the incidence of clinically significant perforation at low dose CT. We also examine the benefits of low dose pre-scan in assessing adequacy of bowel preparation and identifying any other relevant contraindications to CT colonography. MATERIALS AND METHODS: We conducted a retrospective review of all low dose non-contrast CTs performed following failed colonoscopies over a 4-year period (n = 392). We also assessed the adequacy of bowel preparation on a scale of 1-5, in order of increasingly adequate preparation. Incidentally noted bowel pathology and contraindications to CT colonography were also recorded. RESULTS: No perforation was identified either prospectively or in the course of our retrospective review. However, 15 patients (3.8%) were found to have potential contraindications to CT colonography, including: acute diverticulitis, acute colitis, and poor bowel preparation. Overall, the bowel preparation was felt to be adequate (≥ 3) in 86% percent of patients. Two patients (0.5%) identified prospectively had their CT colonography postponed due to poor bowel preparation.


Asunto(s)
Colon/diagnóstico por imagen , Colonografía Tomográfica Computarizada , Colonoscopía/estadística & datos numéricos , Adulto , Anciano , Medios de Contraste , Diatrizoato de Meglumina , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo
8.
Abdom Radiol (NY) ; 45(4): 1049, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31735987

RESUMEN

The original version of this article has an error in the order of authors name. The order of author names should read as "Aileen O'Shea, Timothy Murray, Eavan Thornton, Michael J. Lee and Martina M. Morrin" in the authors group.

9.
J Med Imaging Radiat Oncol ; 63(5): 617-623, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31368659

RESUMEN

Magnetic resonance imaging provides detailed visualisation, identification and extent assessment of many anal disorders. While many studies are performed in the evaluation of malignant processes such as anorectal carcinoma, the primary focus of this pictorial review is benign lesions, which involve the anal canal and perianal spaces. This pictorial review will illustrate the MRI appearances of a variety of benign conditions, which predominantly affect the anal canal, including abscess, fistulae, lipomas, developmental cysts and inflammatory conditions. MRI aids in the identification and characterisation of these abnormalities, of coexisting complications and differentiation from other perineal abnormalities. This pictorial review highlights the spectrum of non-malignant processes involving the perianal region.


Asunto(s)
Enfermedades del Ano/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Medios de Contraste , Humanos
10.
Exp Clin Transplant ; 17(2): 177-182, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30119619

RESUMEN

OBJECTIVES: Prospective renal donors are a select population of healthy individuals who have been thoroughly screened for significant comorbidities before they undergo multidetector computed tomography. Our aim was to determine the prevalence of incidental findings on preoperative multidetector computed tomography in a healthy cohort of potential living donors for kidney transplant. MATERIALS AND METHODS: A prospective study was performed of prospective living kidney transplant donors at a national kidney transplant center. Study inclusion criteria were all potential kidney donors who underwent multidetector computed tomography during the living-donor assessment process over a 5-year period (January 2012 to 2017). RESULTS: Our cohort included 375 potential living donors who had multidetector computed tomography; mean age was 44.33 years (range, 21-71.5 y). In total, there were 228 incidental findings identified in 158 individuals. Of the 375 potential donors, 193 (51%) proceeded to living donor nephrectomy. On multidetector computed tomography, 97 incidental findings were identified in the donor cohort versus 131 in the cohort that did not proceed to donation. Bosniak 1 renal cysts were the most common incidental finding (n = 46) followed by liver cysts < 1.5 cm (n = 42) and urinary tract calculi (n = 21). There was 1 incidentally detected pathologically proven malignancy. CONCLUSIONS: A variety of incidentally detected lesions of moderate to high importance were detected in this healthy donor cohort. Individuals undergoing assessment with multidetector computed tomography for living donor nephrectomy should be counseled on medical, financial, and psychological implications of incidentally detected lesions during the kidney transplant evaluation process.


Asunto(s)
Hallazgos Incidentales , Enfermedades Renales Quísticas/diagnóstico por imagen , Trasplante de Riñón/métodos , Hepatopatías/diagnóstico por imagen , Donadores Vivos , Tomografía Computarizada Multidetector , Nefrectomía , Cálculos Urinarios/diagnóstico por imagen , Adulto , Anciano , Bases de Datos Factuales , Selección de Donante , Femenino , Humanos , Irlanda/epidemiología , Enfermedades Renales Quísticas/epidemiología , Hepatopatías/epidemiología , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Prevalencia , Estudios Retrospectivos , Cálculos Urinarios/epidemiología , Adulto Joven
13.
Eur J Radiol ; 81(1): 31-8, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21131152

RESUMEN

PURPOSE: To compare diagnostic accuracy and patient tolerance of MR colonography with intravenous contrast and luminal air (MRC) to conventional colonoscopy (CC). MATERIALS AND METHODS: IRB approval and written informed consent were obtained. Forty-six patients, both screening and symptomatic, underwent MRC followed by CC. The MRC technique employed 3D T1W spoiled gradient echo sequences performed after the administration of gadopenetate dimeglumine, with parallel imaging. The diagnostic accuracy and tolerance of patients for MRC was compared to CC. RESULTS: Twenty-four polyps were detected in eighteen patients with CC (5 polyps ≥ 10 mm, 4 polyps 6-9 mm, 15 polyps ≤ 5 mm). MRC was 66.7% (12/18) sensitive and 96.4% (27/28) specific for polyp detection on a per-patient basis. When analyzed by polyp size, sensitivity and specificity of MRC was 100% (5/5) and 100% (19/19), respectively, for lesions greater than 10mm, 100% (4/4) and 100% (20/20) for lesions 6-9 mm, and sensitivity of 20% (3/15) lesions less than 5mm. The sensitivity and specificity of MRC for detecting significant lesions (>6mm) was 100% (9/9) and 100% (15/15), respectively. Regarding tolerance of the exams, there were no significant differences between MRC and CC. Thirty-five percent (n=16) of patients preferred MRC as a future screening test compared to 33% (n=15) for CC. CONCLUSION: MRC using air as an intraluminal contrast agent is a feasible and well-tolerated technique for detecting colonic polyps ≥ 6 mm in size. Further studies are warranted.


Asunto(s)
Aire , Colon/patología , Pólipos del Colon/patología , Medios de Contraste/administración & dosificación , Aumento de la Imagen/métodos , Enfermedades del Recto/patología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Inyecciones Intravenosas , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
14.
AJR Am J Roentgenol ; 195(1): W50-4, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20566781

RESUMEN

OBJECTIVE: The purpose of this article is to present the spectrum of radiologic findings of encapsulating peritoneal sclerosis in patients undergoing continuous ambulatory peritoneal dialysis (CAPD). CONCLUSION: Although a rare diagnosis, encapsulating peritoneal sclerosis in patients undergoing CAPD has a high morbidity and mortality. Diagnosis is often delayed because clinical features are insidious and nonspecific. Radiologic imaging may be helpful in the early diagnosis of encapsulating peritoneal sclerosis and in facilitating timely intervention for CAPD patients with encapsulating peritoneal sclerosis.


Asunto(s)
Diálisis Peritoneal Ambulatoria Continua/efectos adversos , Peritoneo/patología , Peritonitis/diagnóstico , Peritonitis/etiología , Medios de Contraste , Humanos , Peritonitis/patología , Esclerosis/patología , Tomografía Computarizada por Rayos X/métodos , Ultrasonografía/métodos
15.
AJR Am J Roentgenol ; 194(5): 1279-87, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20410415

RESUMEN

OBJECTIVE: Full colonic preparation can be onerous and may be poorly tolerated in frail elderly patients. The purpose of this study was to prospectively assess the image quality and diagnostic yield of limited-preparation CT colonography (CTC) in elderly patients with suspected colorectal cancer who were deemed medically unfit or unsuitable for colonoscopy. SUBJECTS AND METHODS: A prospective study was performed of 67 elderly patients with reduced functional status referred for CTC. Participants were prescribed a limited bowel preparation consisting of a low-residue diet for 3 days, 1 L of 2% oral diatrizoate meglumine (Gastrografin) 24 hours before CTC, and 1 L of 2% oral Gastrografin over the 2 hours immediately before CTC. No cathartic preparation was administered. All colonic segments were graded from 1 to 5 for image quality (1, unreadable; 2, poor; 3, equivocal; 4, good; 5, excellent) and reader confidence. Clinical and conventional colonoscopy follow-up findings were documented, and all colonic and extracolonic pathologic findings were documented. RESULTS: Overall image quality and reader confidence in the evaluation of the colon was rated good or excellent in 84% of the colonic segments. Colonic abnormalities were identified in 12 patients (18%), including four colonic tumors, two polyps, and seven colonic strictures. Incidental extraintestinal findings were detected in 43 patients (64%), including nine patients with lesions radiologically consistent with malignancy. CONCLUSION: Limited-preparation low-dose CTC is a feasible and useful minimally invasive technique with which to evaluate the colon and exclude gross pathology (mass lesions and polyps > 1 cm) in elderly patients with diminished performance status, yielding good to excellent image quality.


Asunto(s)
Colonografía Tomográfica Computarizada/métodos , Neoplasias Colorrectales/diagnóstico por imagen , Diatrizoato de Meglumina , Anciano de 80 o más Años , Medios de Contraste , Estudios de Factibilidad , Femenino , Anciano Frágil , Humanos , Masculino , Intensificación de Imagen Radiográfica/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
16.
Radiographics ; 30(1): 201-18, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20083594

RESUMEN

The search for an acceptable colorectal cancer screening examination has led to the development of virtual colonoscopy, which includes both computed tomographic (CT) colonography and magnetic resonance (MR) colonography. As indicated by the much larger number of published studies on CT colonography than on MR colonography, multidetector CT appears to be more suitable for colorectal screening than does MR colonography, in part reflecting the ease and speed of performing CT, as well as the increased spatial resolution, decreased cost, and wider availability of CT colonography. The main advantage of MR colonography over CT colonography is that it does not use ionizing radiation, which has important implications for colorectal cancer screening. The use of dark-lumen MR colonography to screen patients for colorectal cancer as well as other abdominopelvic disease could make it more attractive than CT. With the integration of 3.0-T MR colonography, fecal tagging, and parallel imaging into research and clinical settings, new MR colonography protocols must be optimized. Future MR colonography research should address issues such as image characteristics, presence of artifacts, management of specific absorption rate, and hardware-related modifications.


Asunto(s)
Pólipos del Colon/diagnóstico , Neoplasias Colorrectales/diagnóstico , Medios de Contraste , Aumento de la Imagen/métodos , Imagen por Resonancia Magnética/tendencias , Pólipos del Colon/complicaciones , Neoplasias Colorrectales/etiología , Humanos
17.
J Magn Reson Imaging ; 28(3): 664-72, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18777549

RESUMEN

PURPOSE: To compare various Array Spatial and Sensitivity Encoding Technique (ASSET)-enhanced T2W SSFSE (single shot fast spin echo) and T1-weighted (T1W) 3D SPGR (spoiled gradient recalled echo) sequences for polyp detection and image quality at MR colonography (MRC) in a phantom model. Limitations of MRC using standard 3D SPGR T1W imaging include the long breath-hold required to cover the entire colon within one acquisition and the relatively low spatial resolution due to the long acquisition time. Parallel imaging using ASSET-enhanced T2W SSFSE and 3D T1W SPGR imaging results in much shorter imaging times, which allows for increased spatial resolution. MATERIALS AND METHODS: Using two porcine colon phantoms each with eight simulated 3-10-mm "polyps," baseline reference sequences acquired without ASSET (6-mm slices and readout bandwidth [BW] 62 kHz) were compared with 11 SSFSE and 8 SPGR sequences acquired with 2-fold ASSET acceleration. ASSET-enhanced SSFSE and SPGR sequences comprised BW/matrix combinations ranging from 20-62 kHz/256-352x256, respectively, with slice thicknesses adjusted from 3.0 to 4.5 mm to maintain a 23-26-second acquisition time and 30 cm slab thickness. Two experienced radiologists viewed the datasets in a randomized, blinded fashion. RESULTS: Compared to reference sequences, ASSET-enhanced SSFSE and SPGR sequences facilitated better polyp detection and had similar overall image quality and per-phantom specificity. The two best ASSET-enhanced SSFSE (3 and 4.5 mm slices, each with BW of 62.5 kHz and 352x256 matrices) and three best ASSET-enhanced SPGR BW/slice thickness/matrix combinations of 31 kHz/4.4 msec/192x256; 62/3.4/192x256; and 62/4.0/192x256, respectively, permitted detection of all polyps>or=5 mm. CONCLUSION: Parallel imaging using ASSET-enhanced T2W SSFSE and T1W 3D SPGR improves the ability to detect significant colon polyps in an MRC phantom model.


Asunto(s)
Colon/patología , Pólipos del Colon/patología , Interpretación de Imagen Asistida por Computador/métodos , Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética/métodos , Reconocimiento de Normas Patrones Automatizadas/métodos , Técnica de Sustracción , Algoritmos , Animales , Aumento de la Imagen/métodos , Imagen por Resonancia Magnética/instrumentación , Fantasmas de Imagen , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Porcinos
18.
Radiology ; 244(2): 471-8, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17641367

RESUMEN

PURPOSE: To retrospectively evaluate the positive predictive value (PPV) of computed tomographic (CT) colonography performed in patients who were referred for further examination after incomplete colonoscopy. MATERIALS AND METHODS: This HIPAA-compliant retrospective study was approved by the institutional review board; informed consent was waived. We identified 546 consecutive patients (mean age, 64.1 years; 401 [73.4%] women) who underwent CT colonography after incomplete colonoscopy between November 1999 and December 2002. A retrospective chart review was performed if CT colonography depicted endoscopically nonvisualized lesions 6 mm or greater in diameter. Repeat colonoscopy rate, endoluminal findings, and PPV of CT colonography were determined. Subsequent colonoscopic findings were used as the reference standard. RESULTS: In 72 (13.2%) patients, CT colonography depicted 88 endoscopically nonvisualized lesions 6 mm or greater. Of 11 patients reported to have 12 masses (> or =20 mm), at subsequent colonoscopy, one patient had no mass. Eighteen patients had 23 large (10-19-mm) polyps that they were suspected of having, and 47 patients had 53 medium (6-9-mm) polyps that they were suspected of having. At a median follow-up of 31 months (range, 6-42 months), 45 (63%) of 72 patients underwent follow-up colonoscopy because of their CT colonographic findings. Rates of repeat colonoscopy for masses, large polyps, and medium polyps were 100%, 94%, and 45%, respectively. Per-patient and per-lesion PPVs of CT colonography for masses, large polyps, and medium polyps were 90.9% and 91.7%, 64.7% and 70%, and 33.3% and 30.4%, respectively. CONCLUSION: CT colonography has the potential to become an accepted technique for evaluation of the nonvisualized part of the colon after incomplete colonoscopy, and it can increase the diagnostic yield of masses and clinically important polyps in this part of the colon.


Asunto(s)
Enfermedades del Colon/diagnóstico por imagen , Colonografía Tomográfica Computarizada , Colonoscopía , Medios de Contraste , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Derivación y Consulta , Retratamiento , Estudios Retrospectivos
20.
Am J Physiol Renal Physiol ; 288(4): F637-41, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15572523

RESUMEN

Increased utilization of cross-sectional imaging has resulted in increased detection of incidental renal tumors. The noninvasive characterization of renal tissue has important implications for the diagnosis of renal malignancies and treatment monitoring. Recently, multiple breath-hold averaged proton magnetic resonance spectroscopy ((1)H-MRS) performed at high field has enabled the use of this noninvasive metabolic profiling technique for the investigation of the abdomen. Multiple breath-hold averaged (1)H-MRS at high field (3T) was obtained in the kidneys of 10 healthy volunteers and in renal cell carcinoma tumors of 14 patients. The spectra of normal kidneys showed four main groups of resonances: 1) at 5.4-5.6 ppm, attributed to C6 of cholesterol and the unsaturated parts of the olefinic region of fatty acids; 2) at 4.7 ppm, attributed to the residual water signal; 3) at 3.2 ppm, attributed to trimethylamine moiety of choline metabolites; and 4) at 1.3 and 0.9 ppm, attributed to the methylenes and terminal methyls of lipids. The ratio of the signal at 5.4 ppm to that of 1.3 ppm was 19-fold lower in renal cell carcinomas than in healthy kidneys, tied P = 0.0003 Mann-Whitney U-test, suggesting a decrease in both free cholesterol and the degree of unsaturation of fatty acids in the malignant tissue. This metabolic shift is in agreement with previous ex vivo studies of human renal cell carcinoma. The ability to detect renal metabolic shifts noninvasively may improve the specificity of preoperative renal tissue characterization and may provide a new modality for treatment monitoring.


Asunto(s)
Carcinoma de Células Renales/metabolismo , Colesterol/metabolismo , Ácidos Grasos Insaturados/metabolismo , Neoplasias Renales/metabolismo , Espectroscopía de Resonancia Magnética/métodos , Adulto , Carcinoma de Células Renales/patología , Femenino , Humanos , Neoplasias Renales/patología , Masculino , Persona de Mediana Edad , Protones , Respiración
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