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1.
Curr Probl Diagn Radiol ; 53(2): 246-251, 2024.
Article in English | MEDLINE | ID: mdl-38290903

ABSTRACT

BACKGROUND: Have you ever been in the trenches of a complicated study only to be interrupted by a not-so urgent phone-call? We were, repeatedly- unfortunately. PURPOSE: To increase productivity of radiologists by quantifying the main source of interruptions (phone-calls) to the workflow of radiologists, and too assess the implemented solution. MATERIALS AND METHODS: To filter calls to the radiology consultant on duty, we introduced an automatic voicemail and custom call redirection system. Thus, instead of directly speaking with radiology consultants, clinicians were to first categorize their request and dial accordingly: 1. Inpatient requests, 2. Outpatient requests, 3. Directly speak with the consultant radiologist. Inpatient requests (1) and outpatient requests (2) were forwarded to MRI technologists or clerks, respectively. Calls were monitored in 15-minute increments continuously for an entire year (March 2022 until and including March 2023). Subsequently, both the frequency and category of requests were assessed. RESULTS: 4803 calls were recorded in total: 3122 (65 %) were forwarded to a radiologist on duty. 870 (18.11 %) concerned inpatients, 274 (5.70 %) outpatients, 430 (8.95 %) dialed the wrong number, 107 (2.23 %) made no decision. Throughout the entire year the percentage of successfully avoided interruptions was relatively stable and fluctuated between low to high 30 % range (Mean per month 35 %, Median per month 34.45 %). CONCLUSIONS: This is the first analysis of phone-call interruptions to consultant radiologists in an imaging department for 12 continuous months. More than 35 % of requests did not require the input of a specialist trained radiologist. Hence, installing an automated voicemail and custom call redirection system is a sustainable and simple solution to reduce phone-call interruptions by on average 35 % in radiology departments. This solution was well accepted by referring clinicians. The installation required a one-time investment of only 2h and did not cost any money.


Subject(s)
Radiology Department, Hospital , Radiology , Humans , Radiologists , Radiography , Telephone
3.
Diagnostics (Basel) ; 13(4)2023 Feb 13.
Article in English | MEDLINE | ID: mdl-36832199

ABSTRACT

PURPOSE: To assess the technical (TS) and clinical success (CS) of CT fluoroscopy-guided drainage (CTD) in patients with symptomatic deep pelvic fluid collections following colorectal surgery. METHODS: A retrospective analysis (years 2005 to 2020) comprised 43 drain placements in 40 patients undergoing low-dose (10-20 mA tube current) quick-check CTD using a percutaneous transgluteal (n = 39) or transperineal (n = 1) access. TS was defined as sufficient drainage of the fluid collection by ≥50% and the absence of complications according to the Cardiovascular and Interventional Radiological Society of Europe (CIRSE). CS comprised the marked reduction of elevated laboratory inflammation parameters by ≥50% under minimally invasive combination therapy (i.v. broad-spectrum antibiotics, drainage) within 30 days after intervention and no surgical revision related to the intervention required. RESULTS: TS was gained in 93.0%. CS was obtained in 83.3% for C-reactive Protein and in 78.6% for Leukocytes. In five patients (12.5%), a reoperation due to an unfavorable clinical outcome was necessary. Total dose length product (DLP) tended to be lower in the second half of the observation period (median: years 2013 to 2020: 544.0 mGy*cm vs. years 2005 to 2012: 735.5 mGy*cm) and was significantly lower for the CT fluoroscopy part (median: years 2013 to 2020: 47.0 mGy*cm vs. years 2005 to 2012: 85.0 mGy*cm). CONCLUSIONS: Given a minor proportion of patients requiring surgical revision due to anastomotic leakage, the CTD of deep pelvic fluid collections is safe and provides an excellent technical and clinical outcome. The reduction of radiation exposition over time can be achieved by both the ongoing development of CT technology and the increased level of interventional radiology (IR) expertise.

5.
Rofo ; 193(12): 1436-1444, 2021 Dec.
Article in English, German | MEDLINE | ID: mdl-34352914

ABSTRACT

PURPOSE: Since artificial intelligence is transitioning from an experimental stage to clinical implementation, the aim of our study was to evaluate the performance of a commercial, computer-aided detection algorithm of computed tomography pulmonary angiograms regarding the presence of pulmonary embolism in the emergency room. MATERIALS AND METHODS: This retrospective study includes all pulmonary computed tomography angiogram studies performed in a large emergency department over a period of 36 months that were analyzed by two radiologists experienced in emergency radiology to set a reference standard. Original reports and computer-aided detection results were compared regarding the detection of lobar, segmental, and subsegmental pulmonary embolism. All computer-aided detection findings were analyzed concerning the underlying pathology. False-positive findings were correlated to the contrast-to-noise ratio. RESULTS: Expert reading revealed pulmonary embolism in 182 of 1229 patients (49 % men, 10-97 years) with a total of 504 emboli. The computer-aided detection algorithm reported 3331 findings, including 258 (8 %) true-positive findings and 3073 (92 %) false-positive findings. Computer-aided detection analysis showed a sensitivity of 47 % (95 %CI: 33-61 %) on the lobar level and 50 % (95 %CI 43-56 %) on the subsegmental level. On average, there were 2.25 false-positive findings per study (median 2, range 0-25). There was no significant correlation between the number of false-positive findings and the contrast-to-noise ratio (Spearman's Rank Correlation Coefficient = 0.09). Soft tissue (61.0 %) and pulmonary veins (24.1 %) were the most common underlying reasons for false-positive findings. CONCLUSION: Applied to a population at a large emergency room, the tested commercial computer-aided detection algorithm faced relevant performance challenges that need to be addressed in future development projects. KEY POINTS: · Computed tomography pulmonary angiograms are frequently acquired in emergency radiology.. · Computer-aided detection algorithms (CADs) can support image analysis.. · CADs face challenges regarding false-positive and false-negative findings.. · Radiologists using CADs need to be aware of these limitations.. · Further software improvements are necessary ahead of implementation in the daily routine.. CITATION FORMAT: · Müller-Peltzer K, Kretzschmar L, Negrão de Figueiredo G et al. Present Limitations of Artificial Intelligence in the Emergency Setting - Performance Study of a Commercial, Computer-Aided Detection Algorithm for Pulmonary Embolism. Fortschr Röntgenstr 2021; 193: 1436 - 1444.


Subject(s)
Artificial Intelligence , Pulmonary Embolism , Algorithms , Computers , Female , Humans , Male , Pulmonary Embolism/diagnostic imaging , Radiographic Image Interpretation, Computer-Assisted , Retrospective Studies , Sensitivity and Specificity
6.
Diagnostics (Basel) ; 11(5)2021 Apr 26.
Article in English | MEDLINE | ID: mdl-33926046

ABSTRACT

PURPOSE: To evaluate technical outcome, diagnostic yield and safety of computed tomographic fluoroscopy-guided percutaneous core needle biopsies in patients with mediastinal masses. METHODS: Overall, 155 CT fluoroscopy-guided mediastinal core needle biopsies, performed from March 2010 to June 2020 were included. Size of lesion, size of needle, access path, number of success, number of biopsies per session, diagnostic yield, patient's position, effective dose, rate of complications, tumor localization, size of tumor and histopathological diagnosis were considered. Post-interventional CT was performed, and patients observed for any complications. Complications were classified per the Society of Interventional Radiology (SIR). RESULTS: 148 patients (age, 54.7 ± 18.2) underwent 155 CT-fluoroscopy-guided percutaneous biopsies with tumors in the anterior (114; 73.5%), middle (17; 11%) and posterior (24; 15.5%) mediastinum, of which 152 (98%) were technically successful. For placement of the biopsy needle, in 82 (52.9%) procedures a parasternal trajectory was chosen, in 36 (23.3%) a paravertebral access, in 20 (12.9%) through the lateral intercostal space and in 17 (11%) the thoracic anterior midline, respectively. A total of 136 (89.5%) of the biopsies were considered adequate for a specific histopathologic analysis. Total DLP (dose-length product) was 575.7 ± 488.8 mGy*cm. Mean lesion size was 6.0 ± 3.3 cm. Neoplastic pathology was diagnosed in 115 (75.7%) biopsies and 35 (23%) biopsy samples showed no evidence of malignancy. Minor complications were observed in 18 (11.6%) procedures and major pneumothorax requiring drainage insertion in 3 interventions (1.9%). CONCLUSION: CT fluoroscopy-guided percutaneous core needle biopsy of mediastinal masses is an effective and safe procedure for the initial assessment of patients with mediastinal tumors.

7.
PeerJ ; 8: e10000, 2020.
Article in English | MEDLINE | ID: mdl-33083120

ABSTRACT

It is deemed important to understand cetacean occurrence and distribution to comprehend their ecological roles. The geographical occurrence of species' niche can be used to better describe their potential distribution. The niche can be defined using environmental variables. Those variables are considered static and not affected by biological activities. The present study goal was to assess the occurrence and distribution of cetaceans along the southeastern Brazilian coast, as well as to define the fundamental and realized niche of each species and to investigate niche overlap at local scale. The environmental requirements for each species were also investigated throughout statistical tests. Sighting data were obtained through oceanographic surveys conducted between 2012 and 2015. The environmental variables available on MARSPEC and the software NicheA were used for the ecological niche modeling. A total of twelve cetacean species were identified and the potential distribution areas of the six commonest ones were defined. Even though the species presented different environmental preferences, most of them had partial overlap among niches and potential distribution areas. The environmental heterogeneity of the study area might support the co-occurrence of different species with different environmental requirements.

8.
Quant Imaging Med Surg ; 10(9): 1739-1747, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32879853

ABSTRACT

BACKGROUND: Carotid body tumors (CBTs) depict the most common paraganglioma of the head and neck that can metastasize in up to 15% of cases. They develop either sporadically or hereditarily and may produce catecholamines ("functioning CBTs") resulting in associated symptoms like headache, palpitations or flush. Non-functioning CBTs usually present as slowly and often tender growing mass which may affect adjacent cranial nerves. CBTs can be visualized by ultrasound, CT, MRI or angiography. Pre-surgical interventional embolization, surgical resection and radiation therapy are therapeutical options. The aim of this retrospective single-center study is to assess the safe and real-time evaluation of CBTs by contrast-enhanced ultrasound (CEUS). METHODS: Ten patients with CBT were included in this study on whom CEUS was performed between 2007-2018 (mean age: 62 years). In 6/10 patients, results were confirmed by MRI, 4/12 patients underwent subsequent angiography. CEUS was performed and interpreted by a single consultant radiologist with experience since 2000 (EFSUMB level 3). VueBox® software was used for standardized perfusion quantification. RESULTS: CEUS allowed to detect all CBTs and visualize intratumoral microcirculation. Perfusion quantification was performed in 6/10 cases. CBTs showed significantly reduced peak-enhancement (PE), reduced wash-in perfusion index (WiPI) and significantly elevated time to peak (TTP) compared to common carotid arteries (CCA). CONCLUSIONS: CEUS is a useful and safe tool for identifying CBTs and evaluating intratumoral microperfusion at high spatial and temporal resolutions in real-time. In addition to conventional ultrasound, CT, MRI and digital substraction angiography (DSA), CEUS may be implemented in the future diagnostic work-up and follow-up of CBT patients.

9.
J Int Med Res ; 48(6): 300060520930151, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32529869

ABSTRACT

OBJECTIVE: Hepatocellular carcinoma (HCC) is the most common cause of primary liver cancer. A major part of diagnostic HCC work-up is based on imaging findings from sonography, computed tomography (CT), or magnetic resonance imaging (MRI) scans. Contrast-enhanced ultrasound (CEUS) allows for the dynamic assessment of the microperfusion pattern of suspicious liver lesions. This study aimed to evaluate the diagnostic value of CEUS compared with CT scans for assessing HCC. METHODS: We performed a retrospective, single-center study between 2004 and 2018 on 234 patients with suspicious liver lesions who underwent CEUS and CT examinations. All patients underwent native B-mode, color Doppler and CEUS after providing informed consent. Every CEUS examination was performed and interpreted by a single experienced radiologist (European Federation of Societies for Ultrasound in Medicine and Biology level 3). RESULTS: CEUS was performed on all included patients without occurrence of any adverse effects. CEUS showed a sensitivity of 94%, a specificity of 70%, a positive predictive value of 93% and a negative predictive value of 72% for analyzing HCC compared with CT as the diagnostic gold standard. CONCLUSIONS: CEUS has an excellent safety profile and shows a high diagnostic accuracy in assessing HCC compared with corresponding results from CT scans.


Subject(s)
Carcinoma, Hepatocellular/diagnosis , Liver Neoplasms/diagnosis , Tomography, X-Ray Computed/statistics & numerical data , Ultrasonography, Doppler, Color/statistics & numerical data , Adult , Aged , Aged, 80 and over , Carcinoma, Hepatocellular/pathology , Contrast Media/administration & dosage , Feasibility Studies , Female , Humans , Liver/diagnostic imaging , Liver/pathology , Liver Neoplasms/pathology , Male , Middle Aged , Predictive Value of Tests , Reproducibility of Results , Retrospective Studies , Tomography, X-Ray Computed/adverse effects , Ultrasonography, Doppler, Color/adverse effects , Young Adult
10.
Scand J Urol ; 54(3): 241-247, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32449437

ABSTRACT

Purpose: The aim of the present retrospective single-center study is to evaluate the diagnostic performance of multiparametric ultrasonography for characterizing testicular tumors.Method: Forty-nine patients with testicular tumors, 36 of malignant vs 13 of benign entity, were included in this retrospective single-center study on whom multiparametric sonography, encompassing native B-mode, Color Doppler, contrast-enhanced ultrasound (CEUS) and elastography, was performed between 2011-2018. In 48 of 49 patients, findings from multiparametric analysis were correlated with histopathological results. The applied contrast agent for CEUS was a second-generation blood pool agent. Ultrasonography examinations were performed and interpreted by a single experienced radiologist with more than 15 years of experience (EFSUMB Level 3).Results: Multiparametric ultrasonography was successfully performed in all included patients without any adverse effects. Concomitant testicular microlithiasis, rapid arterial wash-in, elevated values for perfusion quantification - Peak Enhancement (PE), Wash-in Area Under the Curve (WiAUC) and Wash-in Perfusion Index (WiPI) - and higher shear wave velocities were significantly associated with malignancy.Conclusions: Multiparametric ultrasonography depicts a non-ionizing, directly accessible and cost-effective imaging modality that allows for the extensive characterization of testicular tumors, thereby helping to discriminate between malignant and benign entity of testicular tumors.


Subject(s)
Testicular Neoplasms/diagnostic imaging , Adolescent , Adult , Aged , Aged, 80 and over , Child , Humans , Male , Middle Aged , Retrospective Studies , Ultrasonography/methods , Young Adult
11.
Rofo ; 192(11): 1053-1059, 2020 Nov.
Article in English, German | MEDLINE | ID: mdl-32294790

ABSTRACT

PURPOSE: To compare the sensitivity and specificity of contrast-enhanced ultrasound (CEUS), computed tomography (CT) and magnetic resonance imaging (MRI) in the evaluation of unclear renal lesions to the histopathological outcome. MATERIALS AND METHODS: A total of 255 patients with a single unclear renal mass with initial imaging studies between 2005 and 2015 were included. Patient ages ranged from 18 to 86 with (mean age 62 years; SD ±â€Š13). CEUS (255 patients), CT (88 out of 255 patients; 34.5 %) and MRI (36 out of 255 patients; 14.1 %) were used for determining malignancy or benignancy and initial findings were correlated with the histopathological outcome. RESULTS: CEUS showed a sensitivity of 99.1 % (95 % confidence interval (CI): 96.7 %, 99.9 %), a specificity of 80.5 % (95 % CI: 65.1 %, 91.2 %), a positive predictive value (PPV) of 96.4 % (95 % CI: 93.0 %, 98.4 %) and a negative predictive value (NPV) of 94.3 % (95 % CI: 80.8 %, 99.3 %). CT showed a sensitivity of 97.1 % (95 % CI: 89.9 %, 99.6 %), a specificity of 47.4 % (95 % CI: 24.4 %, 71.1 %), a PPV of 87.0 % (95 % CI: 77.4 %, 93.6 %) and a NPV of 81.8 % (95 % CI: 48.2 %, 97.7 %). MRI showed a sensitivity of 96.4 % (95 % CI: 81.7 %, 99.9 %), a specificity of 75.0 % (95 % CI: 34.9 %, 96.8 %), a PPV of 93.1 % (95 % CI: 77.2 %, 99.2 %) and a NPV of 85.7 % (95 % CI: 42.1 %, 99.6 %). Out of the 212 malignant lesions a total of 130 clear cell renal carcinomas, 59 papillary renal cell carcinomas, 7 chromophobe renal cell carcinomas, 4 combined clear cell and papillary renal cell carcinomas and 12 other malignant lesions, e. g. metastases, were diagnosed. Out of the 43 benign lesions a total 10 angiomyolipomas, 3 oncocytomas, 8 benign renal cysts and 22 other benign lesions, e. g. renal adenomas were diagnosed. Using CEUS, 10 lesions were falsely identified as malignant or benign, whereas 8 lesions were false positive and 2 lesions false negative. CONCLUSION: CEUS is an useful method which can be additionally used to clinically differentiate between malignant and benign renal lesions. CEUS shows a comparable sensitivity, specificity, PPV and NPV to CT and MRI. In daily clinical routine, patients with contraindications for other imaging modalities can particularly benefit using this method. KEY POINTS: · Wide availability. · Safe applicability in patients with known renal insufficiency or allergies to iodine or gadolinium. · Comparable sensitivity, specificity, PPV and NPV to CT and MRT. · May lead to a reduction in interventional radiological or surgical interventions. CITATION FORMAT: · Marschner CA, Ruebenthaler J, Schwarze V et al. Comparison of computed tomography (CT), magnetic resonance imaging (MRI) and contrast-enhanced ultrasound (CEUS) in the evaluation of unclear renal lesions. Fortschr Röntgenstr 2020; 192: 1053 - 1058.


Subject(s)
Contrast Media/administration & dosage , Image Enhancement , Kidney Diseases/diagnostic imaging , Kidney Neoplasms/diagnostic imaging , Magnetic Resonance Imaging , Tomography, X-Ray Computed , Ultrasonography , Adolescent , Adult , Aged , Aged, 80 and over , Diagnosis, Differential , Female , Humans , Kidney/diagnostic imaging , Kidney/pathology , Kidney Diseases/pathology , Kidney Neoplasms/pathology , Male , Middle Aged , Young Adult
12.
Scand J Urol ; 54(2): 135-140, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32162575

ABSTRACT

Purpose: The aim of the present retrospective single-center study is to evaluate the diagnostic performance of contrast-enhanced ultrasound (CEUS) in the evaluation of renal oncocytoma.Method: Thirteen patients with histopathologically confirmed renal oncocytoma and 26 patients with histopathologically confirmed renal cell carcinoma were included in this retrospective single-center study on whom CEUS was performed between 2005 and 2015. The applied contrast agent was a second-generation blood pool agent. CEUS examinations were performed and interpreted by a single radiologist with more than 15 years of experience (EFSUMB Level 3).Results: CEUS examinations were successfully performed in all included patients without any adverse effects. Renal oncocytomas showed varying echogenicity (46% hypoechoic, 23% hyperechoic, 8% iso-/hyperechoic, 8% isoechoic). In two cases renal oncocytoma only demarcated upon i.v. application of contrast medium. In bilateral oncocytosis, lesions presented as hyperechoic. Only 23% of renal oncocytomas showed slight vascularization using Color Doppler. No oncocytoma-specific pattern of microperfusion could be elucidated: 85% of the oncocytomas presented hyperenhancing, of whom 50% also showed delayed venous wash-out; 8% of renal oncocytomas showed venous wash-out without early arterial hyperenhancement.Conclusions: Within the frame of the present study and in line with the recent state of knowledge, no specific sonomorphological feature - including CEUS - could be detected allowing for adequate discrimination between oncocytoma and renal cell carcinoma.


Subject(s)
Adenoma, Oxyphilic/diagnostic imaging , Contrast Media , Kidney Neoplasms/diagnostic imaging , Adult , Aged , Aged, 80 and over , Carcinoma, Renal Cell/diagnostic imaging , Diagnosis, Differential , Female , Humans , Male , Middle Aged , Retrospective Studies , Ultrasonography/methods
13.
Ultraschall Med ; 41(1): 29-35, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31362328

ABSTRACT

BACKGROUND: Ultrasound is an essential imaging tool for evaluating physiological and pathological fetal or maternal conditions during pregnancy. Published data is limited with respect to the application of CEUS during pregnancy. CEUS has already been safely applied for assessing uteroplacental blood flow, cesarean scar pregnancy and invasive placenta percreta. CT and MRI scans during pregnancy must be thoroughly evaluated due to harmful ionizing radiation and cerebral gadolinium deposition, respectively. PURPOSE: The aim of the present retrospective single-center study is to assess the diagnostic performance and safety of CEUS during pregnancy to evaluate hepatic lesions of unknown entity. METHODS: 6 pregnant patients who underwent CEUS between 2005 and 2014 (mean age: 32 years; mean weeks of pregnancy: 28 weeks) were included in this study. The applied contrast agent was a second-generation blood-pool agent (SonoVue®, Bracco, Milan, Italy). CEUS examinations were performed and interpreted by a single radiologist with experience since 2000 (EFSUMB Level 3). RESULTS: CEUS was safely performed on all included pregnant women without the occurrence of adverse fetal or maternal events. In the context of the present study, CEUS helped to safely differentiate hepatic metastases, focal nodular hyperplasia, atypical hemangioma, hepatic arteriovenous malformation and cystic echinococcosis. In two patients CEUS determined immediate therapy. CONCLUSION: Although not clinically approved in obstetrics so far, CEUS is a safe imaging modality which, in addition to B-mode and color Doppler ultrasonography, may be applied during pregnancy for further medical indications and to provide helpful information.


Subject(s)
Contrast Media , Liver Neoplasms , Pregnancy Complications, Neoplastic , Ultrasonography, Doppler, Color , Adult , Female , Humans , Liver Neoplasms/diagnostic imaging , Liver Neoplasms/secondary , Pregnancy , Pregnancy Complications, Neoplastic/diagnostic imaging , Retrospective Studies , Ultrasonography, Doppler, Color/adverse effects
15.
J Ultrasound Med ; 39(6): 1047-1056, 2020 Jun.
Article in English | MEDLINE | ID: mdl-31840876

ABSTRACT

The scrotum may be affected by a plethora of different disorders such as infections, vasculopathies, trauma, and manifestations of primary and secondary malignant masses. In addition to the patient's medical history and clinical examination, ultrasound represents the imaging modality of choice to assess scrotal disorders. Time-consuming contrast-enhanced ultrasound and elastography can provide further information to distinguish between benign and malignant testicular mass lesions. The following invited Special Communication gives a comprehensive overview of differential diagnoses of the scrotum and their corresponding sonomorphologic correlates based on representative cases of the Interdisciplinary Ultrasound Center of the University Hospital Munich.


Subject(s)
Scrotum/diagnostic imaging , Scrotum/pathology , Testicular Diseases/diagnostic imaging , Testicular Diseases/pathology , Ultrasonography/methods , Diagnosis, Differential , Humans , Male
16.
Breast Care (Basel) ; 14(3): 142-150, 2019 Jun.
Article in English | MEDLINE | ID: mdl-31316312

ABSTRACT

Breast imaging is a multimodal approach that plays an essential role in the diagnosis of breast cancer. Mammography, sonography, magnetic resonance, and image-guided biopsy are imaging techniques used to search for malignant changes in the breast or precursors of malignant changes in, e.g., screening programs or follow-ups after breast cancer treatment. However, these methods still have some disadvantages such as interobserver variability and the mammography sensitivity in women with radiologically dense breasts. In order to overcome these difficulties and decrease the number of false positive findings, improvements in imaging analysis with the help of artificial intelligence are constantly being developed and tested. In addition, the extraction and correlation of imaging features with special tumor characteristics and genetics of the patients in order to get more information about treatment response, prognosis, and also cancer risk are coming more and more in focus. The aim of this review is to address recent developments in digital analysis of images and demonstrate their potential value in multimodal breast imaging.

17.
Neuroradiology ; 61(2): 129-136, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30402744

ABSTRACT

PURPOSE: Development of a warp-based automated brain segmentation approach of 3D fluid-attenuated inversion recovery (FLAIR) images and comparison to 3D T1-based segmentation. METHODS: 3D FLAIR and 3D T1-weighted sequences of 30 healthy subjects (mean age 29.9 ± 8.3 years, 8 female) were acquired on the same 3T MR scanner. Warp-based segmentation was applied for volumetry of total gray matter (GM), white matter (WM), and 116 atlas regions. Segmentation results of both sequences were compared using Pearson correlation (r). RESULTS: Correlation of GM segmentation results based on FLAIR and T1 was overall good for cortical structures (mean r across all cortical structures = 0.76). Comparatively weaker results were found in the occipital lobe (r = 0.77), central region (mean r = 0.58), basal ganglia (mean r = 0.59), thalamus (r = 0.30), and cerebellum (r = 0.73). FLAIR segmentation underestimated volume of the central region compared to T1, but showed a better anatomic concordance with the occipital lobe on visual review and subcortical structures, when also compared to manual segmentation. Visual analysis of FLAIR-based WM segmentation revealed frequent misclassification of regions of high signal intensity as GM. CONCLUSION: Warp-based FLAIR segmentation yields comparable results to T1 segmentation for most cortical GM structures and may provide anatomically more congruent segmentation of subcortical GM structures. Selected cortical regions, especially the central region and total WM, seem to be underestimated on FLAIR segmentation.


Subject(s)
Brain Mapping/methods , Image Processing, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Magnetic Resonance Imaging/methods , Adult , Female , Humans , Male , Middle Aged
18.
Vasa ; 48(1): 17-22, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30403367

ABSTRACT

Conventional ultrasound is worldwide the first-line imaging modality for the prompt diagnosis in the daily practice because it is a cost-effective and easy to perform technique. The additional application of contrast media has been used to enhance the intravascular contrast and to improve the imaging diagnostic accuracy in the detection, classification and follow-up of vascular pathologies. Contrast-enhanced ultrasound has the advantage of being a safe, fast and dynamic non-invasive imaging tool with excellent results in the diagnosis of acute aortic pathologies, especially the detection of endoleaks after endovascular aneurysm repair. This review describes the diagnostic and therapeutic roles of ultrasound and contrast-enhanced ultrasound imaging in the most common vascular pathologies such as aortic dissections, aneurysms and endoleaks. Keywords: Endoleak, contrast media, ultrasonography, aorta.


Subject(s)
Endovascular Procedures , Ultrasonography , Aorta , Aortic Aneurysm, Abdominal , Endoleak , Humans , Tomography, X-Ray Computed
19.
Biota Neotrop. (Online, Ed. ingl.) ; 19(2): e20180670, 2019. tab, graf
Article in English | LILACS | ID: biblio-989417

ABSTRACT

Abstract: Cetaceans were monitored along ca. 700 km of the southeast coast of Brazil (22°S to 25°S) from 1995 to 2014 using photo-identification. The objective of this study was to identify any presence of long-distance movements for monitored cetacean species and discuss implications. Data on long-range movements of four of the monitored species are presented after the analysis of 321,765 photographs taken for individual identification. Seven individuals from four populations of Guiana dolphins (Sotalia guianensis) considered resident to particular estuaries or bays were reported in dispersal involving movement between pairs of protected areas over long-range distances varying between 86 and 135 km. Three cataloged rough-toothed dolphins (Steno bredanensis), first seen in Guanabara Bay, Rio de Janeiro state (22°46'S) in November 2011, were sighted 240 km southwards as members of the same group in coastal waters of São Paulo state (23°46'S) in July 2014. Water depth for those sightings ranged from 16 to 52.7 m; local sightings of rough-toothed dolphins in Brazil have frequently been in shallow waters, but the species global distribution is usually associated with deeper waters. In a 27-day interval in the spring of 2012, a group of 16 orcas (Orcinus orca) travelled ca. 277 km in shallow coastal waters ranging from 20 to 30 m deep. Orcas are commonly observed between November and February in southeast Brazil, probably in search for prey. In summer months between 2012 and 2014, three Bryde's whales (Balaenoptera edeni) sighted in waters ranging from 14 to 49 m deep, moved between 218 and 327 km. Bryde's whales are usually found in local coastal waters where they spend summer months feeding on sardines. To date, these are the longest estimated movements reported to S. guianensis, S. bredanensis, O. orca and B. edeni in the Southwestern Atlantic Ocean.


Resumo: Cetáceos foram monitorados em cerca de 700 km da costa sudeste do Brasil (22°S a 25°S) entre 1995 e 2014 com o uso da fotoidentificação. O objetivo deste estudo foi de identificar quaisquer presenças de movimentos de longa distância de indivíduos das espécies monitoradas e discutir suas implicações. Dados de movimentos de longa distância de quatro das espécies monitoradas são apresentados após a análise de 321.765 fotos obtidas para identificações individuais. Sete indivíduos de quatro populações de boto-cinza (Sotalia guianensis) consideradas residentes a estuários e baías particulares foram reportados em movimentos de dispersão envolvendo pares de áreas protegidas em distâncias que variaram entre 86 e 135 km. Três golfinhos-de-dentes-rugosos (Steno bredanensis) catalogados e avistados primeiramente na Baía de Guanabara, Rio de Janeiro (22°46'S), em novembro de 2011, foram avistados 240 km mais ao sul como membros de um mesmo grupo nas águas costeiras do Estado de São Paulo (23°46'S) em julho de 2014. A profundidade da água onde essas avistagens aconteceram variou entre 16 e 52,7 m; avistagens de golfinhos-de-dentes-rugosos têm sido efetuadas em águas rasas na costa sudeste do Brasil, embora a distribuição global da espécie esteja associada a águas profundas. Em um intervalo de 27 dias na primavera de 2012, um grupo de 16 orcas (Orcinus orca) se desclocou cerca de 277 km em águas rasas variando entre 20 e 30 m. Orcas são comumente avistadas entre novembro e fevereiro no sudeste do Brasil, possivelmente em busca de presas. Nos meses de verão entre 2012 e 2014, três baleias-de-Bryde (Balaenoptera edeni) avistadas em águas de 14 a 49 m de profundidade, moveram-se entre 218 e 327 km. baleias-de-Bryde são encontradas em águas costeiras locais onde passam os meses de verão se alimentando de sardinhas. Até o presente momento, esses são os deslocamentos estimados como os de maiores distâncias observados para S. guianensis, S. bredanensis, O. orca and B. edeni no Atlântico Sudoeste.

20.
Med Ultrason ; 20(4): 536-538, 2018 Dec 08.
Article in English | MEDLINE | ID: mdl-30534665

ABSTRACT

This case report relates the use of contrast-enhanced ultrasound (CEUS) for the assessment and treatment of a postinterventional cholecystitis, a rare but important complication after transcatheter arterial embolization of a giant hemangioma. Regarding the imaging diagnosis, hemangiomas have specific features allowing a fast recognition by all radiological modalities,and in recent years, especially by CEUS.


Subject(s)
Cholecystitis/diagnostic imaging , Contrast Media , Embolization, Therapeutic/adverse effects , Hemangioma/therapy , Image Enhancement/methods , Liver Neoplasms/therapy , Adult , Cholecystitis/etiology , Embolization, Therapeutic/methods , Female , Hemangioma/diagnostic imaging , Humans , Liver/diagnostic imaging , Liver Neoplasms/diagnostic imaging , Treatment Outcome , Ultrasonography/methods
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