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1.
Acad Radiol ; 26(6): 760-765, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30149976

RESUMO

RATIONALE AND OBJECTIVES: Ductal carcinoma in situ (DCIS) hinders imaging detection due to multifocal appearance and discontinuous growth. Preoperative determination of its extent is therefore challenging. Aim of this study was to investigate the additional benefit of breast magnetic resonance imaging (MRI) to mammography (MG) in the diagnosis of DCIS according to size and grading. MATERIALS AND METHODS: Retrospective analysis of 295 patients with biopsy-proven, pure DCIS. Mean patient age was 57.0 years (27-87 years). All patients obtained MG. Additional MRI was performed in 41.7% (123/295). Mammographic breast density, background parenchymal enhancement (BPE), tumor size and grading were analysed. Tumor size on MG and MRI were compared to histopathological size of the surgical specimen. RESULTS: Mean tumor size was 39.6 mm. DCIS was occult on MG in 24.4% (30/123) and on MRI in 1.6% (2/123). Size was underestimated by 4.6 mm (mean) mammographically. DCIS was high grade in 54.5% (67/123), intermediate grade in 40.7% (50/123) and low grade in 4.9% (6/123). MG was exact regarding tumor size in low grade DCIS, underestimated intermediate grade DCIS by 1 mm (median) and high grade DCIS by 10.5 mm. MRI overestimated low grade DCIS by 1 mm (median), was exact regarding intermediate grade DCIS and underestimated high grade DCIS by 1 mm. BPE did not influence tumor detection and measurement. CONCLUSION: MRI outperforms MG in the detection and size estimation of DCIS and can reduce positive margin rates.


Assuntos
Biópsia/métodos , Neoplasias da Mama , Mama/diagnóstico por imagem , Carcinoma Intraductal não Infiltrante , Imageamento por Ressonância Magnética/métodos , Mamografia/métodos , Densidade da Mama , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Carcinoma Intraductal não Infiltrante/diagnóstico , Carcinoma Intraductal não Infiltrante/patologia , Carcinoma Intraductal não Infiltrante/cirurgia , Precisão da Medição Dimensional , Feminino , Humanos , Pessoa de Meia-Idade , Gradação de Tumores , Cuidados Pré-Operatórios , Estudos Retrospectivos , Carga Tumoral
2.
Cancer Res ; 76(18): 5512-22, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27466286

RESUMO

Differential diagnosis and therapy of heterogeneous breast tumors poses a major clinical challenge. To address the need for a comprehensive, noninvasive strategy to define the molecular and functional profiles of tumors in vivo, we investigated a novel combination of metabolic PET and diffusion-weighted (DW)-MRI in the polyoma virus middle T antigen transgenic mouse model of breast cancer. The implementation of a voxelwise analysis for the clustering of intra- and intertumoral heterogeneity in this model resulted in a multiparametric profile based on [(18)F]Fluorodeoxyglucose ([(18)F]FDG)-PET and DW-MRI, which identified three distinct tumor phenotypes in vivo, including solid acinar, and solid nodular malignancies as well as cystic hyperplasia. To evaluate the feasibility of this approach for clinical use, we examined estrogen receptor-positive and progesterone receptor-positive breast tumors from five patient cases using DW-MRI and [(18)F]FDG-PET in a simultaneous PET/MRI system. The postsurgical in vivo PET/MRI data were correlated to whole-slide histology using the latter traditional diagnostic standard to define phenotype. By this approach, we showed how molecular, structural (microscopic, anatomic), and functional information could be simultaneously obtained noninvasively to identify precancerous and malignant subtypes within heterogeneous tumors. Combined with an automatized analysis, our results suggest that multiparametric molecular and functional imaging may be capable of providing comprehensive tumor profiling for noninvasive cancer diagnostics. Cancer Res; 76(18); 5512-22. ©2016 AACR.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imagem Multimodal/métodos , Tomografia por Emissão de Pósitrons/métodos , Idoso , Animais , Modelos Animais de Doenças , Feminino , Fluordesoxiglucose F18 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos
4.
Acta Radiol ; 56(9): 1078-84, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25232187

RESUMO

BACKGROUND: Published national and international guidelines and consensus meetings on the use of vacuum-assisted biopsy (VAB) give different recommendations regarding the required numbers of tissue specimens depending on needle size and imaging method. PURPOSE: To evaluate the weights of specimens obtained with different VAB needles to facilitate the translation of the required number of specimens between different breast biopsy systems and needle sizes, respectively. MATERIAL AND METHODS: Five different VAB systems and seven different needle sizes were used: Mammotome® (11-gauge (G), 8-G), Vacora® (10-G), ATEC Sapphire™ (9-G), 8-G Mammotome® Revolve™, and EnCor Enspire® (10-G, 7-G). We took 24 (11-G) or 20 (7-10-G) tissue cores from a turkey breast phantom. The mean weight of a single tissue core was calculated for each needle size. A matrix, which allows the translation of the required number of tissue cores for different needle sizes, was generated. Results were compared to the true cumulative tissue weights of consecutively harvested tissue cores. RESULTS: The mean tissue weights obtained with the 11-G / 10-G Vacora® / 10-G Enspire® / 9-G / 8-G Original / 8-G Revolve™ / 7-G needles were 0.084 g / 0.142 g / 0.221 g / 0.121 g / 0.192 g / 0.334 g / 0.363 g, respectively. The calculated required numbers of VAB tissue cores for each needle size build the matrix. For example, the minimum calculated number of required cores according to the current German S3 guideline is 20 / 12 / 8 / 14 / 9 / 5 / 5 for needles of 11-G / 10-G Vacora® / 10-G Enspire® / 9-G / 8-G Original / 8-G Revolve™ / 7-G size. These numbers agree with the true cumulative tissue weights. CONCLUSION: The presented matrix facilitates the translation of the required number of VAB specimens between different needle sizes and thereby eases the implementation of current guidelines and consensus recommendations into clinical practice.


Assuntos
Biópsia por Agulha/instrumentação , Vácuo , Animais , Doenças Mamárias/patologia , Feminino , Humanos , Imagens de Fantasmas , Perus
6.
Eur J Radiol ; 82(10): 1731-7, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23743052

RESUMO

OBJECTIVES: The purpose of the study was to evaluate the sensitivity of breast MRI in the detection of pure DCIS and to analyze the influence of lesion type and nuclear grade. METHODS: 58 consecutive patients with pathologically proven pure DCIS and preoperatively performed breast MRI were retrospectively reviewed and analyzed. Sensitivities in the detection of DCIS were calculated for MRI and mammography (Mx). Influence of MRI lesion type and nuclear grading on DCIS diagnosis was evaluated. RESULTS: MRI detected pure DCIS with a sensitivity of 79.3%. The sensitivity of Mx was lower (69%), but the difference was not statistically significant (p=0.345). 46.2% of the DCIS presented as enhancing mass and 53.8% as non-mass-like enhancement (NMLE). None of the masses but 21.4% (n=6) of the NMLE were underestimated as probably benign (BI-RADS 3). MRI measured lesion sizes showed a moderate correlation (r=0.74) with histopathologically measured lesion sizes. MRI detection rate of DCIS decreased significantly (p=0.0458) with increasing nuclear grade. Calculated sensitivities were 100% for low-grade DCIS, 84.6% for intermediate-grade DCIS, and 66.7% for high-grade DCIS. CONCLUSIONS: In this study MRI could detect pure DCIS more sensitively than Mx. Despite of missing statistically significance preoperative MRI seems to be helpful in patients with DCIS who are eligible for breast conservation. This applies in particular to patients with non-high-grade DCIS because those were significantly more often positive on MRI and significantly more often negative on Mx. Misinterpretation occurs especially in cases of NMLE and high-grade DCIS and therefore a correlation with Mx is also recommended.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Intraductal não Infiltrante/patologia , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
7.
Neurourol Urodyn ; 26(1): 134-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-16941639

RESUMO

AIMS: Functional asymmetry of pelvic floor innervation has been shown to exist in healthy subjects, and has been proposed to be a predictor of increased risk for fecal incontinence in case of trauma. However, this remains to be shown for different clinical conditions such as traumatic childbirth. METHODS: A conventional surface EMG system was used to assess the innervation of the external anal sphincter. A symmetry index was used to define the relative EMG amplitude asymmetry of the external anal sphincter between 0 (symmetric) and 1 (asymmetric). Three cohorts were studied: 40 nulliparous women in the third trimester (Study 1), 15 primiparous women within 6 months following vaginal delivery without clinically apparent anal sphincter trauma (Study 2), and 50 women after childbirth-related third or fourth degree perineal tear 6-12 months postpartum (Study 3). Furthermore, all women underwent conventional anorectal manometry. RESULTS: Sixteen or forty nulliparous women reported signs of fecal incontinence; however, relative asymmetry was not correlated to symptom severity (P = 0.345), and not to manometric measures (Study 1). In Study 2, Women who had suffered clinically apparent anal sphincter trauma (P = 0.07) tended to have a stronger association between incontinence and asymmetry. In Study 3, 19/50 women reported moderate to severe incontinence. Asymmetry and symptom severity were significantly correlated (P < 0.001). Patients with incontinence had a significantly higher asymmetry score than their continent counterparts. CONCLUSION: Functional asymmetry of anal sphincter innervation is significantly associated with incontinence symptoms, but only after childbirth-related sphincter injuries and therefore, should be regarded as an additional risk factor.


Assuntos
Canal Anal/lesões , Canal Anal/inervação , Incontinência Fecal/etiologia , Incontinência Fecal/patologia , Complicações do Trabalho de Parto/patologia , Parto , Adulto , Estudos de Coortes , Eletromiografia , Episiotomia , Incontinência Fecal/epidemiologia , Feminino , Humanos , Lacerações/complicações , Manometria , Complicações do Trabalho de Parto/epidemiologia , Diafragma da Pelve/inervação , Diafragma da Pelve/patologia , Períneo/lesões , Valor Preditivo dos Testes , Gravidez , Prevalência , Fatores de Risco , Incontinência Urinária/epidemiologia , Incontinência Urinária/etiologia , Incontinência Urinária/patologia
8.
Neuroimage ; 31(3): 1004-14, 2006 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-16529950

RESUMO

Ano-rectal stimulation provides an important model for the processing of somatosensory and visceral sensations in the human nervous system. In spite of their anatomical proximity, the anal canal is innervated by somatosensory afferents whereas the rectum is innervated by the visceral nervous system. In a functional magnetic resonance (fMRI) experiment, we examined the cerebral responses to pneumatic balloon distension of these two structures to test whether somatosensory and visceral stimulation elicited distinct brain activations in spite of their spinal convergence. The specificity of the identified activations was analyzed by Bayesian mixed effects modeling. Activations in the parietal operculum were also compared to the location of cytoarchitectonically defined areas OP 1-4, which are part of the secondary somatosensory cortex (SII), to analyze whether the SII region was activated by anal and/or rectal stimulation. The lowest segregation between visceral and somatosensory stimuli was in the insular cortex, which supports the interpretation of the insula as an integrative region, receiving input from different sensory modalities. The most distinct segregation was found in the fronto-parietal operculum. Here the activations following anal and rectal stimulation were not only functionally but also anatomically distinct. Anal sensations were processed similar to other somatosensory stimuli in the SII cortex (area OP 4). Rectal afferents on the other hand were not processed in SII. Rather, they evoked activation at a more anterior location on the precentral operculum. These results demonstrate a functionally and anatomically distinct processing of somatosensory and visceral afferents in the human cerebral cortex.


Assuntos
Vias Aferentes/anatomia & histologia , Mapeamento Encefálico/métodos , Córtex Cerebral/anatomia & histologia , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Células Receptoras Sensoriais/anatomia & histologia , Vísceras/inervação , Fibras Aferentes Viscerais/anatomia & histologia , Adulto , Canal Anal/inervação , Dominância Cerebral/fisiologia , Feminino , Lobo Frontal/anatomia & histologia , Humanos , Modelos Lineares , Masculino , Manometria , Rede Nervosa/anatomia & histologia , Neurônios/fisiologia , Lobo Parietal/anatomia & histologia , Reto/inervação , Córtex Somatossensorial/anatomia & histologia
9.
Prog Brain Res ; 152: 373-84, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16198714

RESUMO

This chapter describes the results of investigations of the upper and lower gastrointestinal tract in subjects with complete and incomplete spinal cord injury. In one study, gastric emptying was investigated and found delayed. The delay was tentatively attributed to a colo-gastric inhibitory reflex triggered by inappropriate colonic emptying. In another study, anorectal motor and sensory functions were measured. Decreased tone of the internal anal sphincter, exaggerated recto-anal reflexes following rectal distension and spontaneous high-amplitude rectal contractions at low distension volumes were among the findings of the study. Some of the subjects, classified as having a complete injury according to usual clinical criteria (American Spinal Injury Association, ASIA), reported sensation of distension of the rectum. This raises the issue of the need for better methods for the clinical assessment of sensory transmission in the spinal cord. Promising results obtained with functional magnetic resonance imaging of the brain during rectal stimulation in a small group of paraplegics, with complete injuries by ASIA criteria, showed evidence of activation of several brain regions.


Assuntos
Gastroenteropatias/fisiopatologia , Trato Gastrointestinal/inervação , Traumatismos da Medula Espinal/fisiopatologia , Animais , Defecação/fisiologia , Gastroenteropatias/patologia , Motilidade Gastrointestinal/fisiologia , Trato Gastrointestinal/fisiologia , Humanos , Imageamento por Ressonância Magnética , Sensação/fisiologia , Traumatismos da Medula Espinal/patologia , Coluna Vertebral/anatomia & histologia
10.
Invest Radiol ; 40(12): 754-60, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16304477

RESUMO

PURPOSE: The authors conducted a clinical evaluation of single-slab, 3-dimensional, T2-weighted turbo-spin-echo (TSE) with high sampling efficiency (SPACE) for high isotropic body imaging with large field-of-view (FoV). MATERIALS AND METHODS: Fifty patients were examined in clinical routine with SPACE (regions of interest: pelvis n=30, lower spine n=12, upper spine n=6, extremities n=4) at 1.5 T. For achieving a high sampling efficiency, parallel imaging, high turbofactor, and magnetization restore pulses were used. In contrast to a conventional TSE imaging technique with constant flip angle refocusing, the refocusing pulse train of the SPACE sequence consists of variable flip angle radiofrequency pulses along the echo train. RESULTS: Signal-to-noise ratio and contrast-to-noise ratio of SPACE images were of sufficient diagnostic value. The possibility of image reconstruction in multiple planes was of clinical relevance in all cases and simplified data analysis. CONCLUSION: The achievement of 3-dimensional, T2-weighted TSE magnetic resonance imaging with isotropic and high spatial resolution and interactive 3-dimensional visualization essentially improve the diagnostic potential of magnetic resonance imaging.


Assuntos
Neoplasias Abdominais/patologia , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Neoplasias da Coluna Vertebral/patologia , Neoplasias Torácicas/patologia , Imagem Corporal Total/métodos , Adolescente , Adulto , Idoso , Algoritmos , Criança , Pré-Escolar , Feminino , Humanos , Imageamento Tridimensional/métodos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
11.
Digestion ; 69(2): 102-11, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15087577

RESUMO

UNLABELLED: While the regular and symmetric innervation of the pelvic floor has been regarded as "established" for many years, recent data indicate that asymmetry of innervation of the sphincters may exists and may contribute to the occurrence and severity of incontinence symptoms in case of pelvic floor trauma. METHODS: A systematic review of published papers on asymmetry of sphincter innervation was performed including studies in healthy volunteers and patients with incontinence. 234 consecutive patients with fecal incontinence were investigated by means of side-separated mass surface EMG from the left and right side anal canal, these data were correlated to clinical and anamnestic findings. RESULTS: The literature survey indicates that asymmetry of sphincter innervation exists in a subgroup of healthy male and female volunteers, and may be a risk factor to become incontinent in case of trauma. Patients with incontinence in whom asymmetry of sphincter innervation could be shown more frequently reported a history of pelvic floor trauma during childbirth. Childbirth per se but not the number of deliveries predicted sphincter asymmetry. Asymmetrically innervated sphincters show a compromised sphincter function in routine anorectal manometry. CONCLUSION: Assessment of sphincter innervation asymmetry may be of value in clinical routine testing of patients with incontinence. However, a new technology is needed to replace mass surface EMG by multi-electrode arrays on a sphincter probe. This is one of the goals of the EU-sponsored research project OASIS.


Assuntos
Incontinência Fecal/fisiopatologia , Diafragma da Pelve/inervação , Estimulação Elétrica , Eletromiografia , Incontinência Fecal/etiologia , Feminino , Humanos , Masculino , Neurônios Motores/fisiologia , Neurônios Aferentes/fisiologia , Incontinência Urinária/fisiopatologia
12.
J Clin Endocrinol Metab ; 88(4): 1785-91, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12679474

RESUMO

The existence of metabolically relevant intramyocellular lipids (IMCL) as assessed by the noninvasive (1)H-magnetic resonance spectroscopy (MRS) has been established. In the present studies, we analyzed the relationships between IMCL in two muscle types [the predominantly nonoxidative tibialis muscle (tib) and the predominantly oxidative soleus muscle (sol)] and anthropometric data, aerobic capacity (VO(2)max, bicycle ergometry, n = 77) and insulin sensitivity (hyperinsulinemic euglycemic clamp, n = 105) using regression analysis. In univariate regression, IMCL (tib) was weakly but significantly correlated with percentage of body fat (r = 0.28, P = 0.01), whereas IMCL (sol) was better correlated with waist-to-hip ratio (r = 0.41, P < 0.0001). No significant univariate correlation with age or maximal aerobic power was observed. After adjusting for adiposity, IMCL (tib) was positively correlated with measures of aerobic fitness. A significant interaction term between VO(2)max and percentage of body fat on IMCL (tib) (P = 0.04) existed (whole model r(2) = 0.26, P = 0.001). In contrast, aerobic fitness did not influence IMCL (sol). No correlation between insulin sensitivity as such and IMCL (tib) (r = -0.13, P = 0.2) or IMCL (sol) (r = 0.03, P = 0.72) was observed. Nethertheless, a significant interaction term between VO(2)max and IMCL on insulin sensitivity existed [P = 0.04 (tib) and P = 0.02 (sol)]; [whole model (sol) r(2) = 0.61, P < 0.0001, (tib) r(2) = 0.60, P < 0.0001]. In conclusion, obesity and aerobic fitness are important determinants of IMCL. IMCL and insulin sensitivity are negatively correlated in untrained subjects. The correlation between the two parameters is modified by the extent of aerobic fitness and cannot be found in endurance trained subjects. Thus, measurements of aerobic fitness and body fat are indispensable for the interpretation of IMCL and its relationship with insulin sensitivity.


Assuntos
Antropometria , Resistência à Insulina , Lipídeos/análise , Músculo Esquelético/química , Consumo de Oxigênio , Tecido Adiposo , Adulto , Glicemia/análise , Composição Corporal , Feminino , Técnica Clamp de Glucose , Humanos , Insulina/sangue , Espectroscopia de Ressonância Magnética , Masculino , Músculo Esquelético/ultraestrutura , Obesidade/fisiopatologia , Oxirredução , Resistência Física , Aptidão Física
13.
J Magn Reson Imaging ; 17(3): 350-7, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12594726

RESUMO

PURPOSE: To assess the muscular lipid content (LC) in different muscle groups of the lower leg by a magnetic resonance imaging technique working with chemical shift selective excitation, and comparison with anthropometric and metabolic data. MATERIALS AND METHODS: Examinations were performed in 67 volunteers (54 male/13 female, age 29 +/- seven years) on a 1.5 T whole body imager, applying a highly selective spectral-spatial technique for fat selective MRI. LC was measured in six calf muscles and correlated with body mass index (BMI), percent body fat (PFAT), and insulin sensitivity (IS) of the subjects. RESULTS: Mean muscular LC of all subjects was between 2.0% (Tibialis posterior [TP]) and 3.8% (Peroneus muscles) with female subjects showing a significantly higher LC in all muscle groups (P < 0.05 each). LCs correlated moderately with BMI (R between 0.39 [TP] and 0.53 [GM]) and with PFAT (R between 0.38 [TP] and 0.62 [GM]). Insulin-resistant subjects showed slightly but not significantly increased LC compared to insulin-sensitive subjects in BMI-matched subgroups. CONCLUSION: The fat-selective MRI technique allows a reliable non-invasive measure of muscular lipids - even in muscle groups with inherent low LC - within a relatively short measurement time of about three minutes. The presented data reveal interesting interrelationships between LC and anthropometric and metabolic data, and therefore provide new insight into muscular fat metabolism.


Assuntos
Antropometria , Perna (Membro)/anatomia & histologia , Lipídeos/análise , Imageamento por Ressonância Magnética , Músculo Esquelético/anatomia & histologia , Adulto , Índice de Massa Corporal , Feminino , Técnica Clamp de Glucose , Humanos , Masculino , Estudos Prospectivos , Valores de Referência , Distribuição por Sexo
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