Gadolinium-based contrast agents (GBCA) were introduced with high expectations for favorable efficacy, low nephrotoxicity, and minimal allergic-like reactions. Nephrogenic systemic fibrosis and proven gadolinium retention in the body including the brain has led to the restriction of linear GBCAs and a more prudent approach regarding GBCA indication and dosing. In this review, we present the chemical, physical, and clinical aspects of this topic and aim to provide an equanimous and comprehensive summary of contemporary knowledge with a perspective of the future. In the first part of the review, we present various elements and compounds that may serve as MRI contrast agents. Several GBCAs are further discussed with consideration of their relaxivity, chelate structure, and stability. Gadolinium retention in the brain is explored including correlation with the presence of metalloprotein ferritin in the same regions where visible hyperintensity on unenhanced T1-weighted imaging occurs. Proven interaction between ferritin and gadolinium released from GBCAs is introduced and discussed, as well as the interaction of other elements with ferritin; and manganese in patients with impaired liver function or calcium in Fahr disease. We further present the concept that only high-molecular-weight forms of gadolinium can likely visibly change signal intensity on unenhanced T1-weighted imaging. Clinical data are also presented with respect to potential neurological manifestations originating from the deep-brain nuclei. Finally, new contrast agents with relatively high relaxivity and stability are introduced. CRITICAL RELEVANCE STATEMENT: GBCA may accumulate in the brain, especially in ferritin-rich areas; however, no adverse neurological manifestations have been detected in relation to gadolinium retention. KEY POINTS: Gadolinium currently serves as the basis for MRI contrast agents used clinically. No adverse neurological manifestations have been detected in relation to gadolinium retention. Future contrast agents must advance chelate stability and relativity, facilitating lower doses.
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
OBJECTIVES: Accurate detection of metastatic brain lesions (MBL) is critical due to advances in radiosurgery. We compared the results of three readers in detecting MBL using T1-weighted 2D spin echo (SE) and sampling perfection with application-optimized contrasts using different flip angle evolution (SPACE) sequences with whole-brain coverage at both 1.5 T and 3 T. METHODS: Fifty-six patients evaluated for MBL were included and underwent a standard protocol (1.5 T, n = 37; 3 T, n = 19), including postcontrast T1-weighted SE and SPACE. The rating was performed by three raters in two sessions > six weeks apart. The true number of MBL was determined using all available imaging including follow-up. Intraclass correlations for intra-rater and inter-rater agreement were calculated. Signal intensity ratios (SIR; enhancing lesion, white matter) were determined on a subset of 46 MBL > 4 mm. A paired t-test was used to evaluate postcontrast sequence order and SIR. Reader accuracy was evaluated by the coefficient of determination. RESULTS: A total of 135 MBL were identified (mean/subject 2.41, SD 6.4). The intra-rater agreement was excellent for all 3 raters (ICC = 0.97-0.992), as was the inter-rater agreement (ICC = 0.995 SE, 0.99 SPACE). Subjective qualitative ratings were lower for SE images; however, signal intensity ratios were higher in SE sequences. Accuracy was high in all readers for both SE (R2 0.95-0.96) and SPACE (R2 0.91-0.96) sequences. CONCLUSIONS: Although SE sequences are superior to gradient echo sequences in the detection of small MBL, they have long acquisition times and frequent artifacts. We show that T1-weighted SPACE is not inferior to standard thin-slice SE sequences in the detection of MBL at both imaging fields. CRITICAL RELEVANCE STATEMENT: Our results show the suitability of 3D T1-weighted turbo spin echo (TSE) sequences (SPACE, CUBE, VISTA) in the detection of brain metastases at both 1.5 T and 3 T. KEY POINTS: • Accurate detection of brain metastases is critical due to advances in radiosurgery. • T1-weighted SE sequences are superior to gradient echo in detecting small metastases. • T1-weighted 3D-TSE sequences may achieve high resolution and relative insensitivity to artifacts. • T1-weighted 3D-TSE sequences have been recommended in imaging brain metastases at 3 T. • We found T1-weighted 3D-TSE equivalent to thin-slice SE at 1.5 T and 3 T.
- Publikační typ
- časopisecké články MeSH
Závěrečná zpráva o řešení grantu Agentury pro zdravotnický výzkum MZ ČR
nestr.
Retence gadolinia po aplikaci MR kontrastních látek v různých orgánech včetně mozku je nedávno objeveným a závažným fenoménem, jehož patofyziologie a klinická relevance nebyly dosud spolehlivě popsány. Retenci gadolinia lze v mozku neinvazivne monitorovat pomocí alterace T1 a T2 relaxačních časů v oblastech s vysokou koncentrací ferritinu, na který se gadolinium váže. Prospektivní studie má za cíl opakovanými kvantitativními MR vyšetřeními, po předchozí aplikaci MR kontrastní látky z klinické indikace, lépe objasnit tento závažný fenomén. Pilotní studie ukazují, že po počátečním zkrácení T1 a T2 relaxačních časů v globus pallidus po aplikaci MR kontrastních látek, dochází k určitému plateau, případně i k jejich prodloužení. Tento fenomén nebyl dosud spolehlivě popsán. Opakovanými nekontrastnmí kvantitativními měřeními u skupiny cca 100 pacientů hodláme tento fenomén podrobně studovat. Srovnatelná skupina zdravých dobrovolníků pak bude obdobně sledována pomocí kvantitativní MR, bez aplikace kontrastní látky.; Gadolinium retention in various organs including the brain after application of MR contrast agents is a important phenomenon. Its pathophysiology and clinical relevance have not yet been reliably evaluated. Gadolinium retention in the brain may be monitored by measuring T1 and T2 relaxation times in regions with high ferritin concentration due to gadolinium binding. The prospective study aims, by means of repeated quantitative MR examinations after clinically-indicated contrast application, to better understand this phenomenon. A pilot study showed that after an initial shortening of T1 and T2 relaxation times in the globus pallidus after repeated applications of MR contrast agents, a certain plateau is reached or relaxation times are prolonged. This phenomenon has not yet been reliably evaluated. By means of repeated non-contrast enhanced quantitative measurements in a group of approximately 100 patients we aim to study this phenomenon more thoroughly. A comparative group of healthy volunteers will also be studied, however contrast agents will not be applied.
- Klíčová slova
- magnetická rezonance, Magnetic resonance, kontrastní látka, retence gadolinia, globus pallidus, nucleus dentatus, contrast agent, gadolinium retention, globus pallidus, dentate nucleus,
- NLK Publikační typ
- závěrečné zprávy o řešení grantu AZV MZ ČR
INTRODUCTION: The prognosis of glioblastoma remains unfavorable. TTFields utilize low intensity electric fields (frequency 150-300 kHz) that disrupt cellular processes critical for cancer cell viability and tumor progression. TTFields are delivered via transducer arrays placed on the patients' scalp. Methods: Between the years 2004 and 2022, 55 patients (20 female), aged 21.9-77.8 years (mean age 47.3±11.8 years; median 47.6 years) were treated with TTFields for newly-diagnosed GBM, and compared to 54 control patients (20 females), aged 27.0-76.7 years (mean age 51.4±12.2 years; median 51.7 years) (p=0.08). All patients underwent gross total or partial resection of GBM. One patient had biopsy only. When available, MGMT promoter methylation status and IDH mutation was detected. RESULTS: Patients on TTFields therapy demonstrated improvements in PFS and OS relative to controls (hazard ratio: 0.64, p=0.031; and 0.61, p=0.028 respectively). TTFields average time on therapy was 74.8% (median 82%): median PFS of these patients was 19.75 months. Seven patients with TTFields usage ≤60% (23-60%, mean 46.3%, median 53%) had a median PFS of 7.95 months (p=0.0356). Control patients with no TTFields exposure had a median PFS of 12.45 months. Median OS of TTF patients was 31.67 months compared to 24.80 months for controls. DISCUSSION: This is the most extensive study on newly-diagnosed GBM patients treated with TTFields, covering a period of 18 years at a single center and presenting not only data from clinical trials but also a group of 36 patients treated with TTFields as a part of routine clinical practice.
- Publikační typ
- časopisecké články MeSH
Léčba mozkového glioblastomu, de novo i rekurentního, pomocí metody Tumor treating fields (Optune™) je schválenou metodou, která je založena na principu, že prochází-li buňkou střídavý elektrický proud určitých charakteristik, buňka ztrácí schopnost se dělit. Tento princip lze aplikovat i u jiných nádorů. Pilotní studie této metody proběhla v České republice a po 15 letech žije 20 % pacientů, kteří byli do studie zařazeni. Na základě dalších provedených mezinárodních studií byla tato léčba zařazena do kritérií léčby glioblastomu v kategorii 1 podle National Comprehensive Cancer Guidelines. Léčba probíhá neinvazivně a hlavním nežádoucím účinkem je podráždění kůže. Metoda je vhodná pro pacienty po ukončení standardní léčby a v dobrém klinickém stavu, bez výrazné progrese nádoru v době zahájení. Terapie je v některých zemích hrazena ze zdravotního pojištění, v České republice probíhají jednání se zdravotními pojišťovnami o její úhradě.
Tumor treating fields (Optune™) is an approved method to treat both de novo and recurrent glioblastoma. The method is based on the fact that an alternating electric current of given characteristics inhibits cell division. This principle can also be applied in other tumors. A pilot study of this method was performed in the Czech Republic and fifteen years later 20% of the patients are alive. Based on further international studies, this method was included in NCNN Category 1 criteria for glioblastoma treatment. The treatment is non-invasive, and the main side effect is local skin irritation. This technique is suitable for patients that have finished standard therapy and are in good clinical condition without significant tumor progression at the time of treatment initiation. In some countries the treatment is reimbursed by health insurance providers. Currently, there are intensive negotiations with health insurance companies about its reimbursement in the Czech Republic.
- Klíčová slova
- Optune,
- MeSH
- elektrostimulační terapie * metody MeSH
- glioblastom * terapie MeSH
- klinická studie jako téma MeSH
- lidé MeSH
- nádory mozku terapie MeSH
- Check Tag
- lidé MeSH
Článek podává přehled o možnostech diagnostiky a základní diferenciální diagnostiky extrapyramidových onemocnění pomocí magnetické rezonance. Soustřeďuje se na rozlišení mezi Parkinsonovou nemocí, atypickými parkinsonskými syndromy, dále popisuje charakteristický MR obraz Huntingtonovy choroby a Wilsonovy nemoci. V rámci širší diferenciální diagnostiky je zmíněn i chronický subdurální hematom a normotenzní hydrocefalus.
The article provides an overview of diagnostic options and basic differential diagnostic approaches for extrapyramidal diseasesusing magnetic resonance imaging. It aims at distinguishing between Parkinson's disease and atypical parkinsonian syndromesas well as describes the characteristic presentation of Huntington's disease and Wilson's disease on magnetic resonance imaging.Moreover, chronic subdural haematoma and normal pressure hydrocephalus are discussed as part of a broader differential diagnosis.
- Klíčová slova
- mnohotná systémová atrofie, Vaskulární parkinsonismus,
- MeSH
- Creutzfeldtova-Jakobova nemoc diagnostické zobrazování diagnóza MeSH
- diferenciální diagnóza MeSH
- Hallervordenův-Spatzův syndrom diagnostické zobrazování diagnóza MeSH
- Huntingtonova nemoc diagnostické zobrazování diagnóza MeSH
- lidé MeSH
- magnetická rezonanční tomografie metody využití MeSH
- mozeček patologie MeSH
- multisystémová atrofie diagnóza klasifikace patofyziologie MeSH
- nemoci bazálních ganglií * diagnostické zobrazování diagnóza MeSH
- Parkinsonova nemoc diagnostické zobrazování diagnóza MeSH
- parkinsonské poruchy klasifikace MeSH
- počítačová rentgenová tomografie MeSH
- progresivní supranukleární obrna diagnostické zobrazování diagnóza MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přehledy MeSH
V článku jsou představeny dvě minimálně invazivní léčebné metody v oblasti páteře - vertebroplastika a epiduroskopie. Vertebroplastika se hojně využívá v terapii převážně osteoporotických fraktur obratlů, lze ji rovněž využít při paliativní léčbě metastáz do obratlových těl a u symptomatických hemangiomů. Je prováděna pod skiaskopickou a často i CT kontrolou většinou v analgosedaci. U cca 90 % pacientů vede při správné indikaci k významnému analgetickému efektu i zpevnění obratlového těla. Epiduroskopie je novou technikou, která si teprve hledá své pevné místo. Jeví se jako slibná zvláště u pacientů s tzv. failed back surgery syndrome, tedy u nemocných s klinicky symptomatickými fibrózními srůsty po většinou opakovaných neurochirurgických operacích. Při správné indikaci mívá v současné době pozitivní efekt u cca třetiny až poloviny pacientů.
Two minimally-invasive techniques in the spinal region are introduced: vertebroplasty and epiduroscopy. Vertebroplasty is mostly used in the treatment of osteoporotic vertebral body fractures, as well as in the palliative treatment of spinal metastases or symptomatic hemangiomas. It is usually performed under fluoroscopic, and often also CT control under analgesic sedation. If correctly indicated an analgesic effect occurs in roughly 90 % of patients. Epiduroscopy is a new technique, which is promising especially in patients with failed back surgery syndrome; patients with clinically-symptomatic fibrous adhesions, generally after repeated surgery. If correctly indicated a positive effect occurs in roughly one third to one half of patients.
- Klíčová slova
- epiduroskopie,
- MeSH
- kyfoplastika MeSH
- lidé MeSH
- miniinvazivní chirurgické výkony MeSH
- osteoporotické fraktury * diagnostické zobrazování chirurgie MeSH
- osteoporóza MeSH
- vertebroplastika * metody využití MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
- přehledy MeSH
