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Currently, no objective method exists to measure the extent of fibrosis in swallowing musculature in head and neck cancer (HNC) patients. We developed and psychometrically tested a method of quantifying fibrosis volume using magnetic resonance imaging (MRI). The overall aim of this study was to determine if clinical MRI is a reliable tool to measure fibrosis of the pharyngeal musculature in patients with HNC managed with RT and to assess its potential to capture changes in fibrosis over time. Eligible participants were adults with HNC treated with radiation therapy (RT) who received minimally two MRIs and videofluoroscopic swallow (VFS) studies from baseline (pre-RT) up to 1-year post-RT. Two neuroradiologists independently contoured fibrosis volume in batches from MRIs using Vitrea™. Sufficient inter-rater reliability was set at Intraclass Correlation Coefficient (ICC) > 0.75. Two speech-language pathologists independently rated VFSs for swallowing impairment using standardized scales, with discrepancies resolved by consensus. MRI and VFS scores were correlated using Spearman's rank coefficient. Participants included 42 adults (male = 33); mean age 59 (SD = 8.8). ICC (95% Confidence Interval) for fibrosis volume was 0.34 (0, 0.76) for batch one and 0.43 (0, 0.82) for batch two. Consensus meetings were held after each batch. Sufficient reliability was reached by batch three (ICC = 0.95 (0.79, 0.99)). Fibrosis volume increased significantly from 3 to 12 months (mean change = 1.28 mL (SD = 5.21), p = 0.006), as did pharyngeal impairment from baseline to 12 months (mean score change = 3.05 (SD = 3.02), p = 0.003). Fibrosis volume moderately correlated with pharyngeal impairment at 3 and 12 months (0.49, p = 0.004 and 0.59, p = 0.005, respectively). We demonstrated a reliable measure of fibrosis volume in swallowing musculature from existing clinical MRIs and identified that larger fibrosis volume was associated with worse swallowing function. The reliable capture of fibrosis volume offers a pragmatic method for early detection of fibrosis and concomitant dysphagia.
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PURPOSE: To evaluate the association of primary tumor volume (TV) with overall survival (OS) and disease-free survival (DFS) in T3 N0-3M0 supraglottic cancers treated with intensity-modulated radiotherapy (IMRT). METHODS: This was a retrospective cohort study involving 239 patients diagnosed with T3 N0-3M0 supraglottic cancers between 2002 and 2018 from seven regional cancer centers in Canada. Clinical data were obtained from the patient records. Supraglottic TV was measured by neuroradiologists on diagnostic imaging. Kaplan-Meier method was used for survival probabilities, and a restricted cubic spline Cox proportional hazards regression analysis was used to analyze TV associations with OS and DFS. RESULTS: Mean (SD) of participants was 65.2 (9.4) years; 176 (73.6%) participants were male. 90 (38%) were N0, and 151 (64%) received concurrent systemic therapy. Mean TV (SD) was 11.37 (12.11) cm3 . With mean follow up (SD) of 3.28 (2.60) years, 2-year OS was 72.7% (95% CI 66.9%-78.9%) and DFS was 53.6% (47.4%-60.6%). Increasing TV was associated (per cm3 increase) with worse OS (HR, 1.01, 95% CI 1.00-1.02, p < 0.01) and DFS (HR, 1.01, 95% CI 1.00-1.02, p = 0.02). CONCLUSIONS: Increasing primary tumor volume is associated with worse OS and DFS in T3 supraglottic cancers treated with IMRT, with no clear threshold. The findings suggest that patients with larger tumors and poor baseline laryngeal function may benefit from upfront laryngectomy with adjuvant radiotherapy.
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Carcinoma de Células Escamosas , Neoplasias Laríngeas , Humanos , Masculino , Feminino , Estudos Retrospectivos , Carcinoma de Células Escamosas/patologia , Carga Tumoral , Canadá , Neoplasias Laríngeas/patologia , Intervalo Livre de Doença , Estadiamento de NeoplasiasRESUMO
The aim of this study was to demonstrate the correlation between ADC values and the ADC/PSAD ratio for potentially malignant prostate lesions classified into ISUP grades and to determine threshold values to differentiate benign lesions (noPCa), clinically insignificant (nsPCa) and clinically significant prostate cancer (csPCa). We enrolled a total of 403 patients with 468 prostate lesions, of which 46 patients with 50 lesions were excluded for different reasons. Therefore, 357 patients with a total of 418 prostate lesions remained for the final evaluation. For all lesions, ADC values were measured; they demonstrated a negative correlation with ISUP grades (p < 0.001), with a significant difference between csPCa and a combined group of nsPCa and noPCa (ns-noPCa, p < 0.001). The same was true for the ADC/PSAD ratio, but only the ADC/PSAD ratio proved to be a significant discriminator between nsPCa and noPCa (p = 0.0051). Using the calculated threshold values, up to 31.6% of biopsies could have been avoided. Furthermore, the ADC/PSAD ratio, with the ability to distinguish between nsPCa and noPCa, offers possible active surveillance without prior biopsy.
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INTRODUCTION: The purpose of this retrospective study was to compare two, widely available software packages for calculation of Dynamic Susceptibility Contrast (DSC) perfusion MRI normalized relative Cerebral Blood Volume (rCBV) values to differentiate tumor progression from pseudoprogression in treated high-grade glioma patients. MATERIAL AND METHODS: rCBV maps processed by Siemens Syngo.via (Siemens Healthineers) and Olea Sphere (Olea Medical) software packages were co-registered to contrast-enhanced T1 (T1-CE). Regions of interest based on T1-CE were transferred to the rCBV maps. rCBV was calculated using mean values and normalized using contralateral normal- appearing white matter. The Wilcoxon test was performed to assess for significant differences, and software-specific optimal rCBV cutoff values were determined using the Youden index. Interrater reliability was evaluated for two raters using the intraclass correlation coefficient. RESULTS: 41 patients (18 females; median age = 59 years; range 21-77 years) with 49 new or size-increasing post-treatment contrast-enhancing lesions were included (tumor progression = 40 lesions; pseudoprogression = 9 lesions). Optimal rCBV cutoffs of 1.31 (Syngo.via) and 2.40 (Olea) were significantly different, with an AUC of 0.74 and 0.78, respectively. Interrater reliability was 0.85. DISCUSSION: We demonstrate that different clinically available MRI DSC-perfusion software packages generate significantly different rCBV cutoff values for the differentiation of tumor progression from pseudoprogression in standard-of-care treated high grade gliomas. Physicians may want to determine the unique value of their perfusion software packages on an institutional level in order to maximize diagnostic accuracy when faced with this clinical challenge. Furthermore, combined with implementation of current DSC-perfusion recommendations, multi-center comparability will be improved.
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Glioma , Feminino , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Glioma/diagnóstico por imagem , Perfusão , SoftwareRESUMO
Importance: The association of primary tumor volume with outcomes in T3 glottic cancers treated with radiotherapy with concurrent chemotherapy remains unclear, with some evidence suggesting worse locoregional control in larger tumors. Objective: To evaluate the association of primary tumor volume with oncologic outcomes in patients with T3 N0-N3 M0 glottic cancer treated with primary (chemo)radiotherapy in a large multi-institutional study. Design, Setting, and Participants: This multi-institutional retrospective cohort study involved 7 Canadian cancer centers from 2002 to 2018. Tumor volume was measured by expert neuroradiologists on diagnostic imaging. Clinical and outcome data were extracted from electronic medical records. Overall survival (OS) and disease-free survival (DFS) outcomes were assessed with marginal Cox regression. Laryngectomy-free survival (LFS) was modeled as a secondary analysis. Patients diagnosed with cT3 N0-N3 M0 glottic cancers from 2002 to 2018 and treated with curative intent intensity-modulated radiotherapy (IMRT) with or without chemotherapy. Overall, 319 patients met study inclusion criteria. Exposures: Tumor volume as measured on diagnostic imaging by expert neuroradiologists. Main Outcomes and Measures: Primary outcomes were OS and DFS; LFS was assessed as a secondary analysis, and late toxic effects as an exploratory analysis determined before start of the study. Results: The mean (SD) age of participants was 66 (12) years and 279 (88%) were men. Overall, 268 patients (84%) had N0 disease, and 150 (47%) received concurrent systemic therapy. The mean (SD) tumor volume was 4.04 (3.92) cm3. With a mean (SD) follow-up of 3.85 (3.04) years, there were 91 (29%) local, 35 (11%) regional, and 38 (12%) distant failures. Increasing tumor volume (per 1-cm3 increase) was associated with significantly worse adjusted OS (hazard ratio [HR], 1.07; 95% CI, 1.03-1.11) and DFS (HR, 1.04; 95% CI, 1.01-1.07). A total of 62 patients (19%) underwent laryngectomies with 54 (87%) of these within 800 days after treatment. Concurrent systemic therapy was associated with improved LFS (subdistribution HR, 0.63; 95% CI, 0.53-0.76). Conclusions and Relevance: Increasing tumor volumes in cT3 glottic cancers was associated with worse OS and DFS, and systemic therapy was associated with improved LFS. In absence of randomized clinical trial evidence, patients with poor pretreatment laryngeal function or those ineligible for systemic therapy may be considered for primary surgical resection with postoperative radiotherapy.
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Carcinoma de Células Escamosas , Neoplasias Laríngeas , Neoplasias da Língua , Masculino , Humanos , Idoso , Feminino , Neoplasias Laríngeas/patologia , Carcinoma de Células Escamosas/patologia , Estudos Retrospectivos , Carga Tumoral , Canadá , Neoplasias da Língua/terapiaRESUMO
Purpose: Biopsy-based assessment of H3 K27 M status helps in predicting survival, but biopsy is usually limited to unusual presentations and clinical trials. We aimed to evaluate whether radiomics can serve as prognostic marker to stratify diffuse intrinsic pontine glioma (DIPG) subsets. Methods: In this retrospective study, diagnostic brain MRIs of children with DIPG were analyzed. Radiomic features were extracted from tumor segmentations and data were split into training/testing sets (80:20). A conditional survival forest model was applied to predict progression-free survival (PFS) using training data. The trained model was validated on the test data, and concordances were calculated for PFS. Experiments were repeated 100 times using randomized versions of the respective percentage of the training/test data. Results: A total of 89 patients were identified (48 females, 53.9%). Median age at time of diagnosis was 6.64 years (range: 1-16.9 years) and median PFS was 8 months (range: 1-84 months). Molecular data were available for 26 patients (29.2%) (1 wild type, 3 K27M-H3.1, 22 K27M-H3.3). Radiomic features of FLAIR and nonenhanced T1-weighted sequences were predictive of PFS. The best FLAIR radiomics model yielded a concordance of .87 [95% CI: .86-.88] at 4 months PFS. The best T1-weighted radiomics model yielded a concordance of .82 [95% CI: .8-.84] at 4 months PFS. The best combined FLAIR + T1-weighted radiomics model yielded a concordance of .74 [95% CI: .71-.77] at 3 months PFS. The predominant predictive radiomic feature matrix was gray-level size-zone. Conclusion: MRI-based radiomics may predict progression-free survival in pediatric diffuse midline glioma/diffuse intrinsic pontine glioma.
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Neoplasias do Tronco Encefálico , Glioma Pontino Intrínseco Difuso , Glioma , Feminino , Humanos , Criança , Intervalo Livre de Progressão , Estudos Retrospectivos , Glioma/diagnóstico por imagem , Glioma/patologia , Imageamento por Ressonância Magnética , Neoplasias do Tronco Encefálico/diagnóstico por imagemRESUMO
Background: mpMRI assesses prostate lesions through their PI-RADS score. The primary goal of this prospective study was to demonstrate the correlation of PI-RADS v2 score and the volume of a lesion with the presence and clinical significance of prostate cancer (PCa). The secondary goal was to determine the extent of additionally PCa in inconspicuous areas. Methods: All 157 patients underwent a perineal MRI/TRUS-fusion prostate biopsy. Targeted biopsies as well as a systematic biopsy were performed. The presence of PCa in the probes was specified by the ISUP grading system. Results: In total, 258 lesions were biopsied. Of the PI-RADS 3 lesions, 24% were neoplastic. This was also true for 36.9% of the PI-RADS 4 lesions and for 59.5% of the PI-RADS 5 lesions. Correlation between ISUP grades and lesion volume was significant (p < 0.01). In the non-suspicious mpMRI areas carcinoma was revealed in 19.7% of the patients. Conclusions: The study shows that the PI-RADS v2 score and the lesion volume correlate with the presence and clinical significance of PCa. However, there are two major points to consider: First, there is a high number of false positive findings. Second, inconspicuous mpMRI areas revealed PCa.
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Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias da Próstata , Humanos , Biópsia Guiada por Imagem , Imageamento por Ressonância Magnética , Masculino , Estudos Prospectivos , Próstata/diagnóstico por imagem , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologiaRESUMO
OBJECTIVES: Innovative physiologic MRI development focuses on depiction of heterogenous vascular and metabolic features in glioblastoma. For this feasibility study, we employed blood oxygenation level-dependent (BOLD) MRI with standardized and precise carbon dioxide (CO2) and oxygen (O2) modulation to investigate specific tumor tissue response patterns in patients with newly diagnosed glioblastoma. MATERIALS AND METHODS: Seven newly diagnosed untreated patients with suspected glioblastoma were prospectively included to undergo a BOLD study with combined CO2 and O2 standardized protocol. %BOLD signal change/mmHg during hypercapnic, hypoxic, and hyperoxic stimulus was calculated in the whole brain, tumor lesion and segmented volumes of interest (VOI) [contrast-enhancing (CE) - tumor, necrosis and edema] to analyze their tissue response patterns. RESULTS: Quantification of BOLD signal change after gas challenges can be used to identify specific responses to standardized stimuli in glioblastoma patients. Integration of this approach with automatic VOI segmentation grants improved characterization of tumor subzones and edema. Magnitude of BOLD signal change during the 3 stimuli can be visualized at voxel precision through color-coded maps overlayed onto whole brain and identified VOIs. CONCLUSIONS: Our preliminary investigation shows good feasibility of BOLD with standardized and precise CO2 and O2 modulation as an emerging physiologic imaging technique to detail specific glioblastoma characteristics. The unique tissue response patterns generated can be further investigated to better detail glioblastoma lesions and gauge treatment response.
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Glioblastoma , Hiperóxia , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Dióxido de Carbono , Circulação Cerebrovascular/fisiologia , Estudos de Viabilidade , Glioblastoma/diagnóstico por imagem , Humanos , Hiperóxia/metabolismo , Imageamento por Ressonância Magnética/métodos , Oxigênio/metabolismoRESUMO
This chapter describes technical considerations and current and future clinical applications of lesion detection using machine learning in the clinical setting. Lesion detection is central to neuroradiology and precedes all further processes which include but are not limited to lesion characterization, quantification, longitudinal disease assessment, prognosis, and prediction of treatment response. A number of machine learning algorithms focusing on lesion detection have been developed or are currently under development which may either support or extend the imaging process. Examples include machine learning applications in stroke, aneurysms, multiple sclerosis, neuro-oncology, neurodegeneration, and epilepsy.
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Inteligência Artificial , Acidente Vascular Cerebral , Algoritmos , Humanos , Aprendizado de Máquina , NeuroimagemRESUMO
PURPOSE: Differentiation of radiation necrosis from tumor progression in brain metastases treated with stereotactic radiosurgery (SRS) is challenging. For this, we assessed the performance of the centrally restricted diffusion sign. METHODS: Patients with brain metastases treated with SRS who underwent a subsequent intervention (biopsy/resection) for a ring-enhancing lesion on preoperative MRI between 2000 and 2020 were included. Excluded were lesions containing increased susceptibility limiting assessment of DWI. Two neuroradiologists classified the location of the diffusion restriction with respect to the post-contrast T1 images as centrally within the ring-enhancement (the centrally restricted diffusion sign), peripherally correlating to the rim of contrast enhancement, both locations, or none. Measures of diagnostic accuracy and 95% CI were calculated for the centrally restricted diffusion sign. Cohen's kappa was calculated to identify the interobserver agreement. RESULTS: Fifty-nine patients (36 female; mean age 59, range 40 to 80) were included, 36 with tumor progression and 23 with radiation necrosis based on histopathology. Primary tumors included 34 lung, 12 breast, 5 melanoma, 3 colorectal, 2 esophagus, 1 head and neck, 1 endometrium, and 1 thyroid. The centrally restricted diffusion sign was seen in 19/23 radiation necrosis cases (sensitivity 83% (95% CI 63 to 93%), specificity 64% (95% CI 48 to 78%), PPV 59% (95% CI 42 to 74%), NPV 85% (95% CI 68 to 94%)) and 13/36 tumor progression cases (difference p < 0.001). Interobserver agreement was substantial, at 0.61 (95% CI 0.45 to 70.8). CONCLUSION: We found a low probability of radiation necrosis in the absence of the centrally restricted diffusion sign.
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Neoplasias Encefálicas , Lesões por Radiação , Radiocirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/cirurgia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Necrose/diagnóstico por imagem , Necrose/etiologia , Necrose/patologia , Lesões por Radiação/diagnóstico por imagem , Lesões por Radiação/etiologia , Lesões por Radiação/cirurgia , Radiocirurgia/efeitos adversos , Radiocirurgia/métodos , Estudos RetrospectivosRESUMO
Purpose Renal lesions are frequent random findings on CT, MRI, and conventional ultrasound. Since they are usually found accidentally, the respective examinations have not been performed optimally to provide a conclusive diagnosis, making additional multiphase contrast-enhanced examinations necessary. The aim of the study is to correlate CEUS findings with the final diagnosis and to determine whether it is a suitable method for the conclusive characterization of undetermined renal lesions. Materials and Methods All CEUS examinations of focal renal lesions performed at our institute between 2007 and 2014 were retrospectively examined. 437 patients with a total of 491 lesions and 543 examinations were included. 54 patients had bilateral lesions. One patient had three lesions in one kidney. Histology was available in 49 cases and follow-ups in 124 cases. The sensitivity, specificity, positive and negative predictive value as well as positive and negative likelihood ratios were calculated. Results There were 54 malignant and 437 benign lesions. The sensitivity and specificity were 0.981/0.954 overall, 1.000/0.956 for cystic lesions, 0.977/0.906 for solid lesions, and 0.971/0.071 for the histologically confirmed lesions. Bosniak classification was consistent in 289 of 301 lesions (96%). Only 12 lesions (3.9%) were falsely assessed as malignant. Conclusion CEUS is an appropriate method for the clarification of undetermined renal lesions. The characterization of cystic lesions according to Bosniak is adequately possible, especially for potentially malignant lesions (types III and IV).
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BACKGROUND: To visualize and assess brain metastases on magnetic resonance imaging, radiologists face an ever-increasing pressure to perform faster and more efficiently. The usage of maximum intensity projections (MIPs) of contrast-enhanced T1-weighed (T1ce) magnetization-prepared rapid acquisition with gradient echo (MP-RAGE) images proposes to increase reading efficiency by increasing lesion conspicuity while reducing in the number of images to be reviewed. AIM: To assess if MIPs save reading time and achieve the same level of diagnostic accuracy as standard 1 mm T1ce images for the detection of brain metastases. METHODS: Forty-four patients were included in this retrospective study. Axial reformations of T1ce MP-RAGE (TR/TE = 2300/2.25 ms, resolution = 1 mm3 ) images were analyzed and post-processed into 5 and 10 mm MIPs. Two readers evaluated the randomly assorted images and recorded reading time. Reading time differences were analyzed using the Wilcoxon test, and inter-reader statistics were performed using Bland-Altman plots. RESULTS: About 22.5 61.2 s/study and 43.8 ± 159.9 s/study were saved using 5 and 10 mm MIPs, respectively. Combined average sensitivity was 92.0% for 5 mm MIPs and 86.3% for 10 mm MIPs compared to standard 1 mm axial slices, with an average rate of 0.98 and 0.57 false positives per study, respectively CONCLUSION: While 5 mm and 10 mm T1ce MP-RAGE MIPs showed a clinical benefit in reducing reading times for evaluation of brain metastases, they should be used in conjunction with standard 1 mm images for best sensitivity and specificity, a practice which possibly annuls their benefit.
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Neoplasias Encefálicas/diagnóstico , Encéfalo/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Imageamento Tridimensional , Adulto , Idoso , Neoplasias Encefálicas/secundário , Meios de Contraste/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e EspecificidadeRESUMO
Background and purpose To demonstrate the clinical feasibility of a novel MRI pulse sequence, Golden-angle radial sparse parallel MRI (GRASP) through comparison to the current imaging technique, dynamic T1- weighted contrast enhanced (DCE) imaging in terms of image quality and lesion depiction in the detection of microlesions (microadenomas and cysts) of the pituitary gland. MATERIALS AND METHODS: 16 patients (11 microadenomas, 5 cysts) underwent two MRI examinations (Siemens 1.5T and 3T) on separate dates, one using standard DCE (temporal resolution 30â¯s) and the other using GRASP (temporal resolution of 4.4â¯s). Two neuroradiologists separately recorded measures of image quality (Scale 1-5, 5â¯=â¯best), lesion size and contrast arrival times in terms of first and best lesion conspicuity. RESULTS: In qualitiative analysis there were no significant differences in terms of average visual image sharpness (DCE 3.9⯱â¯0.9, GRASP 3.9⯱â¯0.9) or visual contrast scores (DCE 4.1⯱â¯1.2, GRASP 4.4⯱â¯0.8). Pearson's correlation coefficients for interreader lesion measurements (width and height, mm) ranged from substantial to almost perfect agreement (râ¯=â¯0.73 to 0.88). Analysis of contrast arrival times revealed an average lesion first-conspicuity time of 60.7⯱â¯16.7â¯s for DCE compared to 50.2⯱â¯10.3â¯s for GRASP with a difference of 10.5⯱â¯16.2â¯s (pâ¯=â¯0.023). CONCLUSION: Depiction of pituitary microlesions is feasible with GRASP, which has the potential to increase sensitivity through higher temporal resolutions combined with isotropic acquisition allowing for multi-planar reconstructions; this remains to be proven in larger cohorts.
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Adenoma/diagnóstico por imagem , Meios de Contraste/química , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética , Hipófise/diagnóstico por imagem , Adulto , Idoso , Cistos/diagnóstico por imagem , Feminino , Hormônio do Crescimento Humano/metabolismo , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Neoplasias Hipofisárias/diagnóstico por imagem , Prevalência , Prolactinoma/diagnóstico por imagem , Qualidade de Vida , Reprodutibilidade dos Testes , Estudos RetrospectivosRESUMO
Infections may constitute a serious complication in patients with chronic lymphocytic leukemia (CLL). New treatment agents including obinutuzumab and ibrutinib have improved the progression-free survival in CLL, and data suggest a similar overall infection risk and a limited risk of opportunistic infections when compared to standard chemo-immunotherapy. Nevertheless, cases of opportunistic infections including non-tuberculous mycobacterial (NTM) in CLL patients have recently been published. We present a case of a 74-year old man with extensive prior CLL treatment history, including most recently obinutuzumab. He developed an abscess of the psoas muscle and inguinal lymphadenopathy. An inguinal node biopsy specimen showed infection with Mycobacterium avium, confirmed by broad-spectrum mycobacterial PCR, M. avium-specific PCR, and mycobacterial culture. This case and our literature review suggest that physicians should be aware of opportunistic infections in patients with CLL. Diagnostic differentiation from CLL disease progression, Richter's transformation to aggressive lymphoma, and secondary malignancy relies on histological and appropriate microbiological studies from biopsy material of affected organs. Infection prophylaxis in CLL should be considered, including vaccinations and intravenous immune globulin replacement.
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PURPOSE: A 3D fat-navigator (3D FatNavs)-based retrospective motion correction is an elegant approach to correct for motion as it requires no additional hardware and can be acquired during existing 'dead-time' within common 3D protocols. The purpose of this study was to clinically evaluate 3D FatNavs in the work-up of brain tumors. METHODS: An MRI-based fat-excitation motion navigator incorporated into a standard MPRAGE sequence was acquired in 40 consecutive patients with (or with suspected) brain tumors, pre and post-Gadolinium injection. Each case was categorized into key anatomical landmarks, the temporal lobes, the infra-tentorial region, the basal ganglia, the bifurcations of the middle cerebral artery, and the A2 segment of the anterior cerebral artery. First, the severity of motion in the non-corrected MPRAGE was assessed for each landmark, using a 5-point score from 0 (no artifacts) to 4 (non-diagnostic). Second, the improvement in image quality in each pair and for each landmark was assessed blindly using a 4-point score from 0 (identical) to 3 (strong correction). RESULTS: The mean image improvement score throughout the datasets was 0.54. Uncorrected cases with light and no artifacts displayed scores of 0.50 and 0.13, respectively, while cases with moderate artifacts, severe artifacts, and non-diagnostic image quality revealed a mean score of 1.17, 2.25, and 1.38, respectively. CONCLUSION: Fat-navigator-based retrospective motion correction significantly improved MPRAGE image quality in restless patients during MRI acquisition. There was no loss of image quality in patients with little or no motion, and improvements were consistent in patients who moved more.
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Neoplasias Encefálicas/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Pontos de Referência Anatômicos , Artefatos , Meios de Contraste , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Meglumina , Pessoa de Meia-Idade , Movimento (Física) , Compostos Organometálicos , Estudos RetrospectivosRESUMO
PURPOSE: The aim of this pilot study was to assess the clinical feasibility, diagnostic yield, advantages, and disadvantages of structured reporting for routine MRI-reading in patients with primary diagnosis of intracranial tumors as compared to traditional neuroradiological free text reporting. METHODS: A structured MRI reporting template was developed covering pathological, anatomical, and functional aspects in an itemized fashion. Retrospectively, 60 consecutive patients with first diagnosis of an intracranial tumor were selected from the radiology information system/PACS system. Structured reporting was performed by a senior neuroradiologist, blinded to clinical and radiological data. Reporting times were measured per patient. The diagnostic content was compared to free text reporting which was independently performed on the same MRI exams by two other neuroradiologists. The comparisons were categorized per item as: "congruent," "partially congruent," "incongruent," or "not mentioned in free-style report." RESULTS: Tumor-related items: congruent findings were found for all items (17/17) with congruence rates ranging between 98 and 39% per item. Four items achieved congruence rates ≥90%, 5 items >80%, and 9 items ≥70%. Partially congruent findings were found for all items in up to 50% per item. Incongruent findings were present in 7/17 items in up to 5% per item. Free text reports did not mention 12 of 17 items (range 7-43% per item). Non-tumor-related items, including brain atrophy, microangiopathy, vascular pathologies, and various extracranial pathologies, which were not mentioned in free-text reports between 18 and 85% per item. Mean reporting time for structured reporting was 7:49 min (3:12-17:06 min). CONCLUSION: First results showed that expert structured reporting ensured reliable detection of all relevant brain pathologies along with reproducible documentation of all predefined diagnostic items, which was not always the case for free text reporting. A mean reporting time of 8 min per patient seems clinically feasible.
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OBJECTIVES: Analysis of a single slice of a tumor to extract biomarkers for texture analysis may result in loss of information. We investigated correlation of fractional volumes to entire tumor volumes and introduced expanded regions of interest (ROIs) outside the visual tumor borders in glioblastoma. MATERIALS AND METHODS: Retrospective slice-by-slice volumetric texture analysis on 46 brain magnetic resonance imaging subjects with histologically confirmed glioblastoma was performed. Fractional volumes were analyzed for correlation to total volume. Expanded ROIs were analyzed for significant differences to conservative ROIs. RESULTS: As fractional tumor volumes increased, correlation with total volume values for mean, SD, mean of positive pixels, skewness, and kurtosis increased. Expanding ROI by 2 mm resulted in significant differences in all textural values. CONCLUSIONS: Fractional volumes may provide an optimal trade-off for texture analysis in the clinical setting. All texture parameters proved significantly different with minimal expansion of the ROI, underlining the susceptibility of texture analysis to generating misrepresentative tumor information.