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1.
Ann Surg Oncol ; 29(1): 493-499, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34331163

RESUMO

BACKGROUND: Injury to the artery of Adamkiewicz (AKA) during surgery may lead to spinal cord ischemia and severe neurologic complications. Posterior mediastinal tumors may be adjacent to AKA, but data on preoperative visualization of AKA in children are rare. This study analyzed the importance of identifying the AKA preoperatively by spinal digital subtraction angiography (DSA) in children with posterior mediastinal tumors for therapeutic procedure. METHODS: Between 2002 and 2021, 36 children with posterior mediastinal tumors were evaluated for surgery at the authors' clinic. In 10 children with left-sided or bilateral tumor located at vertebral levels T8 to L1, spinal DSA was performed during preoperative workup to assess AKA. The patient and tumor characteristics as well as the diagnostic and therapeutic procedures were analyzed. RESULTS: The median age of the 10 children at examination was 69 months (range, 16-217 months). Three of the children were younger than 2 years. The tumor entities were neuroblastoma, ganglioneuroblastoma, ganglioneuroma, local relapse of a hepatocellular carcinoma, and neurofibroma. The AKA was identified in all cases, and proximity to the tumor was detected in four patients, three of whom had their planned surgery changed to irradiation. No complications occurred during spinal DSA or surgery. CONCLUSIONS: In posterior mediastinal pediatric tumors, spinal DSA is a safe and reliable method for preoperative visualization of the AKA. It can show proximity to the tumor and guide the local therapy, thereby avoiding critical intra- and postoperative situations.


Assuntos
Neoplasias Hepáticas , Neoplasias do Mediastino , Artérias , Criança , Humanos , Neoplasias do Mediastino/diagnóstico por imagem , Neoplasias do Mediastino/cirurgia , Mediastino , Recidiva Local de Neoplasia
2.
Neurosurg Rev ; 45(4): 2671-2679, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34601710

RESUMO

The expression of somatostatin receptors in meningioma is well established. First, suggestions of a prognostic impact of SSTRs in meningioma have been made. However, the knowledge is based on few investigations in small cohorts. We recently analyzed the expression of all five known SSTRs in a large cohort of over 700 meningiomas and demonstrated significant correlations with WHO tumor grade and other clinical characteristics. We therefore expanded our dataset and additionally collected information about radiographic tumor recurrence and progression as well as clinically relevant factors (gender, age, extent of resection, WHO grade, tumor location, adjuvant radiotherapy, neurofibromatosis type 2, primary/recurrent tumor) for a comprehensive prognostic multivariate analysis (n = 666). The immunohistochemical expression scores of SSTR1, 2A, 3, 4, and 5 were scored using an intensity distribution score ranging from 0 to 12. For recurrence-free progression analysis, a cutoff at an intensity distribution score of 6 was used. Univariate analysis demonstrated a higher rate of tumor recurrence for increased expression scores for SSTR2A, SSTR3, and SSTR4 (p = 0.0312, p = 0.0351, and p = 0.0390, respectively), while high expression levels of SSTR1 showed less frequent tumor recurrences (p = 0.0012). In the Kaplan-Meier analysis, a higher intensity distribution score showed a favorable prognosis for SSTR1 (p = 0.0158) and an unfavorable prognosis for SSTR2A (0.0143). The negative prognostic impact of higher SSTR2A expression remained a significant factor in the multivariate analysis (RR 1.69, p = 0.0060). We conclude that the expression of SSTR2A has an independent prognostic value regarding meningioma recurrence.


Assuntos
Neoplasias Meníngeas , Meningioma , Receptores de Somatostatina , Humanos , Imuno-Histoquímica , Neoplasias Meníngeas/diagnóstico , Neoplasias Meníngeas/patologia , Meningioma/diagnóstico , Meningioma/patologia , Recidiva Local de Neoplasia , Prognóstico , Receptores de Somatostatina/metabolismo
3.
J Neurooncol ; 155(3): 247-254, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34800210

RESUMO

INTRODUCTION: Meningiomas are the most common benign intracranial neoplasms. CNS invasion in meningiomas has been integrated into the 2016 WHO classification of CNS tumors as a stand-alone criterion for atypia. Since then, its prognostic impact has been debated based on contradictory results from retrospective analyses. The aim of the study was to elucidate whether histopathological evidence of CNS invasion is associated with increased proliferative potential. METHODS: We have conducted a quantified measurement of the proliferation marker Ki67 and analyzed its association with CNS invasion determined by histology together with other established prognostic markers of progression. Routine, immunohistochemical staining for Ki67 were digitalized and automatic quantification was done using Image J software. RESULTS: Overall, 1718 meningiomas were assessed. Histopathological CNS invasion was seen in 108 cases (6.7%). Uni- and multivariate analysis revealed a significantly higher Ki67 proliferation rate in meningiomas with CNS invasion (p < 0.0001 and p = 0.0098, respectively). CONCLUSIONS: Meningiomas with histopathological CNS invasion show a higher proliferative activity.


Assuntos
Neoplasias Meníngeas , Meningioma , Proliferação de Células , Humanos , Antígeno Ki-67/análise , Neoplasias Meníngeas/patologia , Meningioma/patologia , Estudos Retrospectivos
4.
Neurosurg Rev ; 44(6): 3459-3469, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33751282

RESUMO

Calvarial lesions are rare and can present as a variety of different diseases. The lesions can be palpable on the skin and cause local pain and paraesthesia and, depending on the location, neurological deficits can also occur. This research aims to present an overview of typical imaging features as well as neurosurgical management. We examined the charts of patients who underwent surgery on a calvarial lesion in our department between 2004 and 2017 (n=133). Retrospectively, the pre-, intra-, and postoperative data were analyzed with morphological and histological findings and compared with each other. Pain, swelling, cosmetically disturbing, and neurological deficits were the main complaints. Seventy-seven lesions were limited to the bone, while another 56 lesions showed an infiltrating growth in the adjacent tissue. Depending on the clinical signs and suspected diagnosis, a biopsy, a partial removal, or a complete resection was performed. Histiocytosis (n=20), meningiomas (n=20), metastases (n=19), and osteomas (n=16) were the most common lesions. Fibrous dysplasia (n=6) and intraosseous hemangioma (n=9) were less common; other lesions were present only in isolated cases. Imaging features may suggest the lesion to be benign or malignant, but the diagnosis can be only confirmed by histological examination. The surgical strategy depends on the complaints, location of the lesion, and suspected diagnosis. Adjuvant treatment should be initiated according to the histological findings.


Assuntos
Displasia Fibrosa Óssea , Neoplasias Meníngeas , Meningioma , Humanos , Estudos Retrospectivos , Crânio/diagnóstico por imagem , Crânio/cirurgia
5.
Neurosurg Rev ; 44(2): 1083-1091, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32297071

RESUMO

Glial tumors in the cerebellopontine angle (CPA) are uncommon and comprise less than 1% of CPA tumors. We present four cases of pilocytic astrocytoma of the CPA (PA-CPA) that were treated in our department. Patients who received surgical treatment for PA-CPA from January 2004 to December 2019 were identified by a computer search of their files from the Department of Neurosurgery, Tübingen. Patients were evaluated for initial symptoms, pre- and postoperative facial nerve function and cochlear function, complications, and recurrence rate by reviewing surgical reports, patient documents, neuroradiological data, and follow-up data. We identified four patients with PA-CPA out of about 1500 CPA lesions (~ 0.2%), which were surgically treated in our department in the last 16 years. Of the four patients, three were male, and one was a female patient. Two were adults, and two were children (mean age 35 years). A gross total resection was achieved in three cases, and a subtotal resection was attained in one case. Two patients experienced a moderate facial palsy immediately after surgery (House-Brackmann grade III). In all cases, the facial function was intact or good (House-Brackmann grades I-II) at the long-term follow-up (mean follow-up 4.5 years). No mortality occurred during follow-up. Three of the patients had no recurrence at the latest follow-up (mean latest follow-up 4.5 years), while one patient had a slight recurrence. PA-CPA can be safely removed, and most complications immediately after surgery resolve in the long-term follow-up.


Assuntos
Astrocitoma/cirurgia , Ângulo Cerebelopontino/cirurgia , Gerenciamento Clínico , Neuroma Acústico/cirurgia , Procedimentos Neurocirúrgicos/métodos , Idoso , Astrocitoma/complicações , Astrocitoma/diagnóstico por imagem , Ângulo Cerebelopontino/diagnóstico por imagem , Criança , Paralisia Facial/diagnóstico por imagem , Paralisia Facial/etiologia , Paralisia Facial/cirurgia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/cirurgia , Neuroma Acústico/complicações , Neuroma Acústico/diagnóstico por imagem
6.
Radiologe ; 61(11): 999-1004, 2021 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-34605945

RESUMO

BACKGROUND: There are a multitude of application possibilities of artificial intelligence (AI) and structured reporting (SR) in radiology. The number of scientific publications have continuously increased for many years. There is an extensive portfolio of available AI algorithms for, e.g. automatic detection and preselection of pathologic patterns in images or for facilitating the reporting workflows. Even machines already use AI algorithms for improvement of operating comfort. METHOD: The use of SR is essential especially for the extraction of automatically evaluable semantic data from radiology results reports. Regarding eligibility in certification processes, the use of SR is mandatory for the accreditation of the German Cancer Society as an oncological center or outside Germany, such as the European Cancer Center. RESULTS: The data from SR can be automatically evaluated for the purpose of patient care, research and educational purposes and quality assurance. Lack of information and a high degree of variability often hamper the extraction of valid information from free-text reports using neurolinguistic programming (NLP). Against the background of supervised training, AI algorithms or k­nearest neighbors (KNN) require a considerable amount of validated data. The semantic data from SR can also be processed by AI and used for training. CONCLUSION: The AI and SR are separate entities within the field of radiology with mutual dependencies and significant added value. Both have a high potential for profound upcoming changes and further developments in radiology.


Assuntos
Inteligência Artificial , Radiologia , Algoritmos , Humanos , Radiografia , Fluxo de Trabalho
7.
Neurol Sci ; 41(12): 3625-3632, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32462389

RESUMO

PURPOSE: The updated 2016 CNS World Health Organization classification differentiates three main groups of diffuse glioma according to their molecular characteristics: astrocytic tumors with and without isocitrate dehydrogenase (IDH) mutation and 1p/19q co-deleted oligodendrogliomas. The present study aimed to determine whether dynamic susceptibility contrast magnetic resonance imaging (DSC-MRI) is an independent prognostic marker within the molecular subgroups of diffuse glioma. METHODS: Fifty-six patients with treatment-naive gliomas and advanced preoperative MRI examination were assessed retrospectively. The mean and maximal normalized cerebral blood volume values from DSC-MRI within the tumors were measured. Optimal cutoff values for the 1-year progression-free survival (PFS) were defined, and Kaplan-Meier analyses were performed separately for the three glioma subgroups. RESULTS: IDH wild-type astrocytic tumors had a higher mean and maximal perfusion than IDH-mutant astrocytic tumors and oligodendrogliomas. Patients with IDH wild-type astrocytic tumors and a low mean or maximal perfusion had a significantly shorter PFS than patients of the same group with high perfusion (p = 0.0159/0.0112). Furthermore, they had a significantly higher risk for early progression (hazard ratio = 5.6/5.1). This finding was independent of the methylation status of O6-methylguanin-DNA-methyltransferase and variations of the therapy. Within the groups of IDH-mutant astrocytic tumors and oligodendrogliomas, the PFS of low and highly perfused tumors did not differ. CONCLUSION: High perfusion upon initial diagnosis is not compellingly associated with worse short-term prognosis within the different molecular subgroups of diffuse glioma. Particularly, the overall highly perfused group of IDH wild-type astrocytic tumors contains tumors with low perfusion but unfavorable prognosis.


Assuntos
Neoplasias Encefálicas , Glioma , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/genética , Glioma/diagnóstico por imagem , Glioma/genética , Humanos , Isocitrato Desidrogenase/genética , Imageamento por Ressonância Magnética , Mutação , Prognóstico , Estudos Retrospectivos
8.
Neuroradiology ; 61(7): 775-782, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31001647

RESUMO

PURPOSE: To assess the prevalence of false-positive meningeal contrast enhancement in patients with solid tumors who were undergoing chemotherapy. METHODS: A total of 2572 magnetic resonance imaging (MRI) examinations of the brain were retrospectively evaluated by two readers for the presence of pathological meningeal contrast enhancement conspicuous for neoplastic meningitis. These patients either had malignant melanoma, breast or lung cancer, or lymphoma. The reference standards were cerebrospinal fluid cytology results and follow-up MRI. In cases with pathological contrast enhancement that decreased upon follow-up and non-malignant cytology, the enhancement pattern was further described as pial or dural, local or diffuse, or supra- or infra-tentorial. Moreover, the underlying therapy regimes were assessed. RESULTS: The final study cohort included 78 patients (51 females, median age 57 years), of which 11 patients (14.1%) had a repeated non-malignant cytology ('pseudomeningeosis'). In one case, this finding, a granular pleocytosis, was attributed to previous radiotherapy. Of the remaining patients, seven were receiving multimodal, immunotherapy-based therapy regimens. Patients with unsuspicious cytology had a predominantly supratentorial distribution pattern in comparison to patients with neoplastic meningitis. CONCLUSIONS: The overall prevalence of the presence of false-positive meningeal contrast enhancement is low (< 1%) and not associated with specific imaging patterns. We hypothesize that there is a possible relationship between immunotherapy and 'pseudomeningeosis'. Therefore, in all cases with suspected neoplastic meningitis, the cerebrospinal fluid should be analyzed to confirm the diagnosis, especially in patients undergoing immunotherapy.


Assuntos
Imageamento por Ressonância Magnética/métodos , Carcinomatose Meníngea/diagnóstico por imagem , Carcinomatose Meníngea/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Estudos Transversais , Reações Falso-Positivas , Feminino , Humanos , Masculino , Carcinomatose Meníngea/secundário , Pessoa de Meia-Idade , Estudos Retrospectivos
9.
J Neurooncol ; 139(2): 373-381, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29667086

RESUMO

INTRODUCTION: To assess the predictive value of magnetic resonance imaging (MRI) gadolinium enhancement as a prognostic factor in the 2016 World Health Organization Classification of Tumors of the Central Nervous System integrated glioma groups. METHODS: Four-hundred fifty patients with histopathologically confirmed glioma were retrospectively assessed between 07/1997 and 06/2014 using gadolinium enhancement, survival, and relevant prognostic molecular data [isocitrate dehydrogenase (IDH); alpha-thalassemia/mental retardation syndrome X-linked (ATRX); chromosome 1p/19q loss of heterozygosity; and O6-methylguanine DNA methyltransferase (MGMT)]. The Kaplan-Meier method was used to assess univariate survival data. A multivariate Cox proportional hazards model was performed on significant results from the univariate analysis. RESULTS: There were significant differences in survival between patient age (p < 0.0001), WHO glioma grades (p < 0.0001), and integrated molecular profiles (p < 0.0001). Patients with IDH1/2 mutation, loss of ATRX expression, and methylated MGMT promoter showed significantly better survival than those with the IDHwild-type (p < 0.0001), retained ATRX expression (p < 0.0001), and unmethylated MGMT promoter (p = 0.019). Survival was significantly better in patients without gadolinium enhancement (p = 0.009) who were in the IDHwild-type glioma and glioma with retained ATRX expression groups (p = 0.018 and 0.030, respectively). CONCLUSIONS: In univariate analysis, the presence of gadolinium enhancement on preoperative MRI scans is an unfavorable factor for survival. Regarding the molecular subgroups, gadolinium enhancement is an unfavorable prognostic factor in gliomas with IDHwild-type and those with ATRX retention. However, in multivariate analysis only patient age, IDH1/2 mutation status, MGMT promoter methylation status, and WHO grade IV are relevant for predicting survival.


Assuntos
Neoplasias do Sistema Nervoso Central/diagnóstico por imagem , Meios de Contraste , Gadolínio , Glioma/diagnóstico por imagem , Imageamento por Ressonância Magnética , Adulto , Neoplasias do Sistema Nervoso Central/metabolismo , Neoplasias do Sistema Nervoso Central/mortalidade , Neoplasias do Sistema Nervoso Central/patologia , Feminino , Glioma/metabolismo , Glioma/mortalidade , Glioma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Período Pré-Operatório , Prognóstico , Estudos Retrospectivos , Análise de Sobrevida
10.
Neuroradiology ; 60(4): 381-389, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29464269

RESUMO

PURPOSE: The use of dynamic susceptibility contrast (DSC) perfusion and 11C-methionine positron emission tomography (MET-PET) for glioma grading is currently not standardized. The purpose of this study was to identify regions of interest (ROIs) that enable the best performance and clinical applicability in both methods, as well as to evaluate the complementarity of DSC perfusion and MET-PET in spatial hotspot definition. METHODS: In 41 patient PET/MRI datasets, different ROIs were drawn: in T2-hyperintense tumour, in T2-hyperintense tumour and adjacent oedema and in tumour areas with contrast enhancement, altered perfusion or pathological radiotracer uptake. The performance of DSC perfusion and MET-PET using the different ROIs to distinguish high- and low-grade gliomas was assessed. The spatial overlap of hotspots identified by DSC perfusion and MET-PET was assessed visually. RESULTS: ROIs in T2 fluid attenuated inversion recovery (FLAIR) sequence-hyperintense tumour revealed the most significant differences between high- and low-grade gliomas and reached the highest diagnostic performance in both DSC perfusion (p = 0.046; area under the curve = 0.74) and MET-PET (p = 0.007; area under the curve = 0.80). The combination of methods yielded an area under the curve of 0.80. Hotspots were completely overlapped in one half of the patients, partially overlapped in one third of the patients and present in only one method in approximately 20% of the patients. CONCLUSIONS: For multi-parametric examinations with DSC perfusion and MET-PET, we recommend an ROI definition based on T2-hyperintense tumour. DSC perfusion and MET-PET contain complementary information concerning the spatial hotspot definition.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Glioma/diagnóstico por imagem , Glioma/patologia , Imagem Multimodal/métodos , Adulto , Idoso , Radioisótopos de Carbono , Meios de Contraste , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Metionina , Pessoa de Meia-Idade , Gradação de Tumores , Compostos Organometálicos , Tomografia por Emissão de Pósitrons
11.
Br J Neurosurg ; 32(1): 37-43, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29205071

RESUMO

PURPOSE: Traumatic brain injury is an important health concern in equestrian sports. Nevertheless, the use of safety helmets, especially in recreational riding, is reported to be rare. The purpose of this study was to perform the first matched-pairs analysis of traumatic brain injury with regard to the use of helmets. MATERIALS AND METHODS: In a multicenter retrospective database analysis 40 patients (mean age: 35 ± 17.13 years; 34 female & 6 male) were combined in 20 matched pairs based on age group, gender and trauma mechanism. Admission trauma computed tomography was qualitatively analyzed for the presence or absence of fractures or intracranial hemorrhage. Quantitatively, in patients with intracranial hemorrhage dedicated volumetry of the blood volume was performed. Odds ratio and relative risk were calculated for the endpoints fractures and intracranial hemorrhage. Crude risk ratio and lesion volume differences between helmeted and unhelmeted riders were compared. RESULTS: Concerning skull fractures, in this cohort 6 patients (85.7% of all patients with fractures) did not wear a helmet and only one (14.3%) wore a helmet (p = .068).and fractures were considered more complex in the unhelmeted subgroup. Intracranial hemorrhage occurred significantly more often in the unhelmeted subgroup (10 vs. 2; p = .008). Moreover, the total lesion volume with 19.31 ± 23.93ml in the unhelmeted subgroup, presenting with intracranial hemorrhage, was significantly higher than in the control group (0.65 ± 0.35ml; p = .002). Odds ratios were 9 for intracranial hemorrhage (p = .014) and 8.14 for skull fractures without helmet (p = .09). Altogether, the relative risk for intracranial bleeding for unhelmeted riders was 5-fold higher and the relative risk reduction was 96% by wearing a safety helmet. CONCLUSIONS: Under consideration of comparable trauma mechanisms, horseback riders that do not wear a safety helmet are at risk to suffer significantly more severe brain injury than helmeted riders. Therefore, safety helmets are recommendable for all horseback riders.


Assuntos
Traumatismos em Atletas/prevenção & controle , Lesões Encefálicas Traumáticas/prevenção & controle , Dispositivos de Proteção da Cabeça , Cavalos , Adolescente , Adulto , Animais , Traumatismos em Atletas/diagnóstico por imagem , Traumatismos em Atletas/epidemiologia , Encéfalo/diagnóstico por imagem , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Lesões Encefálicas Traumáticas/epidemiologia , Criança , Estudos de Coortes , Feminino , Humanos , Hemorragia Intracraniana Traumática/diagnóstico por imagem , Hemorragia Intracraniana Traumática/prevenção & controle , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos/estatística & dados numéricos , Estudos Retrospectivos , Fraturas Cranianas/diagnóstico por imagem , Fraturas Cranianas/prevenção & controle , Tomografia Computadorizada por Raios X , Adulto Jovem
12.
Neuroimage ; 155: 245-256, 2017 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-28473286

RESUMO

The clinical use of Magnetic Resonance Imaging (MRI) and Positron Emission Tomography (PET) has proven to be a strong diagnostic tool in the field of neurology. The reliability of these methods to confirm clinical diagnoses has guided preclinical research to utilize these techniques for the characterization of animal disease models. Previously, we demonstrated that an endothelial cell-specific ablation of the murine Serum Response Factor (SrfiECKO) results in blood brain barrier (BBB) breakdown and hemorrhagic stroke. Taking advantage of this mouse model we here perform a comprehensive longitudinal, multiparametric and in vivo imaging approach to reveal pathophysiological processes occurring before and during the appearance of cerebral microbleeds using combined PET and MRI. We complement our imaging results with data regarding animal behavior and immunohistochemistry. Our results demonstrate diffusion abnormalities in the cortical brain tissue prior to the onset of cerebral microbleeds. Diffusion reductions were accompanied by significant increments of [18F]FAZA uptake before the onset of the lesions in T2WI. The Open Field behavioral tests revealed reduced activity of SrfiECKO animals, whereas histology confirmed the presence of hemorrhages in cortical regions of the mouse brain and iron deposition at lesion sites with increased hypoxia inducible factor 1α, CD31 and glial fibrillary acidic protein expression. For the first time, we performed a thorough evaluation of the prodromal period before the occurrence of spontaneous cerebral microbleeds. Using in vivo PET and MRI, we show the pathological tissue changes that occur previous to gross blood brain barrier (BBB) disruption and breakage. In addition, our results show that apparent diffusion coefficient (ADC) reduction may be an early biomarker of BBB disruption proposing an alternate clinical interpretation. Furthermore, our findings remark the usefulness of this novel SrfiECKO mouse model to study underlying mechanisms of hemorrhagic stroke.


Assuntos
Barreira Hematoencefálica/diagnóstico por imagem , Córtex Cerebral/diagnóstico por imagem , Hemorragias Intracranianas/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Tomografia por Emissão de Pósitrons/métodos , Sintomas Prodrômicos , Acidente Vascular Cerebral/diagnóstico , Animais , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Transgênicos
13.
J Neurooncol ; 131(1): 93-101, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27604789

RESUMO

The purpose of this study is to assess the diagnostic performance of diffusion kurtosis imaging (DKI) for in vivo molecular profiling of human glioma. Normalized mean kurtosis (MKn) and mean diffusivity (MDn) metrics from DKI were assessed in 50 patients with histopathologically confirmed glioma. The results were compared in regard to the WHO-based histological findings and molecular characteristics leading to integrated diagnosis (Haarlem Consensus): isocitrate-dehydrogenase (IDH1/2) mutation status, alpha-thalassemia/mental retardation syndrome X-linked (ATRX) expression, chromosome 1p/19q loss of heterozygosity (LOH), and O6-methylguanine DNA methyltransferase (MGMT) promoter methylation status. MKn was significantly lower in tumors with IDH1/2 mutation (0.43 ± 0.09) and ATRX loss of expression (0.41 ± 0.11) than in those with IDH1/2 wild type (0.57 ± 0.09, p < 0.001) and ATRX maintained expression (0.51 ± 0.10, p = 0.004), respectively. Regarding the integrated molecular diagnosis, MKn was significantly higher in primary glioblastoma (0.57 ± 0.10) than in astrocytoma (0.39 ± 0.11, p < 0.001) and oligodendroglioma (0.47 ± 0.05, p = 0.003). MK may be used to provide insight into the human glioma molecular profile regarding IDH1/2 mutation status and ATRX expression. Considering the diagnostic and prognostic significance of these molecular markers, MK appears to be a promising in vivo biomarker for glioma. The diagnostic performance of MK seems to fit more with the integrated molecular approach than the conventional histological findings of the current WHO 2007 classification.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/genética , Imagem de Difusão por Ressonância Magnética/métodos , Glioma/diagnóstico por imagem , Glioma/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Aberrações Cromossômicas , Cromossomos Humanos Par 1/genética , Feminino , Seguimentos , Humanos , Processamento de Imagem Assistida por Computador , Isocitrato Desidrogenase/genética , Masculino , Pessoa de Meia-Idade , Mutação/genética , O(6)-Metilguanina-DNA Metiltransferase/genética , Estudos Retrospectivos , Estatísticas não Paramétricas , Adulto Jovem , Talassemia alfa/genética
14.
Neuroradiology ; 59(7): 649-654, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28580532

RESUMO

PURPOSE: This paper aims to evaluate a new iterative metal artifact reduction algorithm for post-interventional evaluation of brain tissue and intracranial arteries. METHODS: The data of 20 patients that underwent follow-up cranial CT and cranial CT angiography after clipping or coiling of an intracranial aneurysm was retrospectively analyzed. After the images were processed using a novel iterative metal artifact reduction algorithm, images with and without metal artifact reduction were qualitatively evaluated by two readers, using a five-point Likert scale. Moreover, artifact strength was quantitatively assessed in terms of CT attenuation and standard deviation alterations. RESULTS: The qualitative analysis yielded a significant increase in image quality (p = 0.0057) in iteratively processed images with substantial inter-observer agreement (ĸ = 0.72), while the CTA image quality did not differ (p = 0.864) and even showed vessel contrast reduction in six cases (30%). The mean relative attenuation difference was 27% without metal artifact reduction vs. 11% for iterative metal artifact reduction images (p = 0.0003). CONCLUSIONS: The new iterative metal artifact reduction algorithm enhances non-enhanced CT image quality after clipping or coiling, but in CT-angiography images, the contrast of adjacent vessels can be compromised.


Assuntos
Angiografia Cerebral , Angiografia por Tomografia Computadorizada , Embolização Terapêutica/métodos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/terapia , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Artefatos , Meios de Contraste , Feminino , Humanos , Iopamidol/análogos & derivados , Masculino , Metais , Pessoa de Meia-Idade , Interpretação de Imagem Radiográfica Assistida por Computador , Resultado do Tratamento
18.
Diagnostics (Basel) ; 13(18)2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37761230

RESUMO

(1) Background: to test the diagnostic performance of a fully convolutional neural network-based software prototype for clot detection in intracranial arteries using non-enhanced computed tomography (NECT) imaging data. (2) Methods: we retrospectively identified 85 patients with stroke imaging and one intracranial vessel occlusion. An automated clot detection prototype computed clot location, clot length, and clot volume in NECT scans. Clot detection rates were compared to the visual assessment of the hyperdense artery sign by two neuroradiologists. CT angiography (CTA) was used as the ground truth. Additionally, NIHSS, ASPECTS, type of therapy, and TOAST were registered to assess the relationship between clinical parameters, image results, and chosen therapy. (3) Results: the overall detection rate of the software was 66%, while the human readers had lower rates of 46% and 24%, respectively. Clot detection rates of the automated software were best in the proximal middle cerebral artery (MCA) and the intracranial carotid artery (ICA) with 88-92% followed by the more distal MCA and basilar artery with 67-69%. There was a high correlation between greater clot length and interventional thrombectomy and between smaller clot length and rather conservative treatment. (4) Conclusions: the automated clot detection prototype has the potential to detect intracranial arterial thromboembolism in NECT images, particularly in the ICA and MCA. Thus, it could support radiologists in emergency settings to speed up the diagnosis of acute ischemic stroke, especially in settings where CTA is not available.

19.
Mol Imaging Biol ; 25(2): 363-374, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36074223

RESUMO

Cerebral hypoperfusion and vascular dysfunction are closely related to common risk factors for ischemic stroke such as hypertension, dyslipidemia, diabetes, and smoking. The role of inhibitory G protein-dependent receptor (GiPCR) signaling in regulating cerebrovascular functions remains largely elusive. We examined the importance of GiPCR signaling in cerebral blood flow (CBF) and its stability after sudden interruption using various in vivo high-resolution magnetic resonance imaging techniques. To this end, we induced a functional knockout of GiPCR signaling in the brain vasculature by injection of pertussis toxin (PTX). Our results show that PTX induced global brain hypoperfusion and microvascular collapse. When PTX-pretreated animals underwent transient unilateral occlusion of one common carotid artery, CBF was disrupted in the ipsilateral hemisphere resulting in the collapse of the cortically penetrating microvessels. In addition, pronounced stroke features in the affected brain regions appeared in both MRI and histological examination. Our findings suggest an impact of cerebrovascular GiPCR signaling in the maintenance of CBF, which may be useful for novel pharmacotherapeutic approaches to prevent and treat cerebrovascular dysfunction and stroke.


Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral , Animais , Isquemia Encefálica/etiologia , Infarto Cerebral , Acidente Vascular Cerebral/patologia , Encéfalo/patologia , Proteínas de Ligação ao GTP
20.
Rofo ; 195(2): 135-138, 2023 02.
Artigo em Inglês, Alemão | MEDLINE | ID: mdl-35913055

RESUMO

As a result of technical developments and greater availability of imaging equipment, the number of neuroradiological examinations is steadily increasing [1]. Due to improved image quality and sensitivity, more details can be detected making reporting more complex and time-intensive. At the same time, reliable algorithms increasingly allow quantitative image analysis that should be integrated in reports in a standardized manner. Moreover, increasing digitalization is resulting in a decrease in the personal exchange between neuroradiologists and referring disciplines, thereby making communication more difficult. The introduction of structured reporting tailored to the specific disease and medical issue [2, 3] and corresponding to at least the second reporting level as defined by the German Radiological Society (https://www.befundung.drg.de/de-DE/2908/strukturierte-befundung/) is therefore desirable to ensure that the quality standards of neuroradiological reports continue to be met.The advantages of structured reporting include a reduced workload for neuroradiologists and an information gain for referring physicians. A complete and standardized list with relevant details for image reporting is provided to neuroradiologists in accordance with the current state of knowledge, thereby ensuring that important points are not forgotten [4]. A time savings and increase in efficiency during reporting were also seen [5]. Further advantages include report clarity and consistency and better comparability in follow-up examinations regardless of the neuroradiologist's particular reporting style. This results in better communication with the referring disciplines and makes clinical decision significantly easier [6, 7]. Although the advantages are significant, any potential disadvantages like the reduction of autonomy in reporting and inadequate coverage of all relevant details and any incidental findings not associated with the main pathology in complex cases or in rare diseases should be taken into consideration [4]. Therefore, studies examining the advantages of structured reporting, promoting the introduction of this system in the clinical routine, and increasing the acceptance among neuroradiologists are still needed.Numerous specific templates for structured reporting, e. g., regarding diseases in cardiology and oncology, are already available on the website www.befundung.drg.de . Multiple sclerosis (MS) is an idiopathic chronic inflammatory and neurodegenerative disease of the central nervous system and is the most common non-trauma-based inflammatory neurological disease in young adults. Therefore, it has significant individual and socioeconomic relevance [8]. Magnetic resonance imaging (MRI) plays an important role in the diagnosis, prognosis evaluation, and follow-up of this disease. MRI is established as the central diagnostic method in the diagnostic criteria. Therefore, specific changes are seen on MRI in almost all patients with a verified MS diagnosis [9]. Reporting of MRI datasets regarding the brain and spinal cord of patients with MS includes examination of the images with respect to the relevant medical issue in order to determine whether the McDonald criteria, which were revised in 2017 [10] and define dissemination in time and space clinically as well as with respect to MRI based on the recommendations of the MAGNIMS groups [11, 12], are fulfilled. A more precise definition of lesion types and locations according to the recommendations of an international expert group [13] is discussed in the supplementary material. Spinal cord signal abnormalities are seen in up to 92 % of MS patients [14-16] and are primarily located in the cervical spine [15]. The recommendations of the MAGNIMS-CMSC-NAIMS working group published in 2021 [11] explicitly recommend the use of structured reporting for MS patients.Therefore, a reporting template for evaluating MRI examinations of the brain and spinal cord of patients with MS was created as part of the BMBF-funded DIFUTURE consortium in consensus with neuroradiological and neurological experts in concordance with the recommendations mentioned above [11] and was made available for broad use (https://github.com/DRGagit/ak_befundung). The goal is to facilitate efficient and comprehensive evaluation of patients with MS in the primary diagnostic workup and follow-up imaging. These reporting templates are consensus-based recommendations and do not make any claim to general validity or completeness. The information technology working group (@GIT) of the German Radiological Society and the German Society for Neuroradiology strive to keep the reporting templates presented here up-to-date with respect to new research data and recommendations of the MAGNIMS-CMSC-NAIMS group [11]. KEY POINTS:: · consensus-based reporting templates. · template for the structured reporting of MRI examinations of patients with multiple sclerosis. · structured reporting might facilitate communication between neuroradiologists and referring disciplines. CITATION FORMAT: · Riederer I, Mühlau M, Wiestler B et al. Structured Reporting in Multiple Sclerosis - Consensus-Based Reporting Templates for Magnetic Resonance Imaging of the Brain and Spinal Cord. Fortschr Röntgenstr 2023; 195: 135 - 138.


Assuntos
Esclerose Múltipla , Doenças Neurodegenerativas , Adulto Jovem , Humanos , Esclerose Múltipla/diagnóstico por imagem , Consenso , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Medula Espinal/diagnóstico por imagem
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