PURPOSE: A new generation of CT detectors were recently developed with the ability to measure individual photon's energy and thus provide spectral information. The aim of this work was to assess the performance of simultaneous fat and iron quantification using a clinical photon-counting CT (PCCT) and its comparison to dual-energy CT (DECT), MRS and MRI at 3 T. METHODS: Two 3D printed cylindrical phantoms with 32 samples (n = 12 fat fractions between 0 % and 100 %, n = 20 with mixtures of fat and iron) were scanned with PCCT and DECT scanners for comparison. A three-material decomposition approach was used to estimate the volume fractions of fat (FF), iron and soft tissue. The same phantoms were examined by MRI (6-echo DIXON, a.k.a. Q-DIXON) and MRS (multi-echo STEAM, a.k.a. HISTO) at 3 T for comparison. RESULTS: PCCT, DECT, MRI and MRS computed FFs showed correlation with reference fat fraction values in samples with no iron (r > 0.98). PCCT decomposition showed slightly weaker correlation with FFref in samples with added iron (r = 0.586) compared to MRI (r = 0.673) and MRS (r = 0.716) methods. On the other hand, it showed no systematic over- or underestimation. Surprisingly, DECT decomposition-derived FF showed strongest correlation (r = 0.758) in these samples, however systematic overestimation was observed. FF values computed by three-material PCCT decomposition, DECT decomposition, MRI and MRS were unaffected by iron concentration. CONCLUSIONS: This in-vitro study shows for the first time that photon-counting computed tomography may be used for quantification of fat content in the presence of iron deposits.
Symptomatické neurologické komplikácie sa vyskytujú u 15-30 % pacientov s infekčnou endokarditídou. Zároveň sa u 35-60 % pacientov vyskytujú klinicky nemé mozgové embólie. Staphylococcus aureus je patogén, ktorý najčastejšie spôsobuje postihnutie nervového systému. Uvádzame prípad 67-ročného muža s infekčnou endokarditídou po stomatologickom výkone, ktorý sa prejavil ako spondylodiscitída a mnohopočetná embolizácia do mozgu, vrátane mozgového abscesu, ktorý si vyžiadal neurochirurgickú drenáž. Po 6 týždňoch liečby širokospektrálnymi antibiotikami a komplexnej podpornej terapii sme pacienta prepustili v uspokojivom somatickom a psychickom stave. Pokračuje príprava pacienta na kardiochirurgický výkon.
Symptomatic neurological complications occur in 15-30% of patients with infective endocarditis. At the same time, other clinically silent cerebral embolisms occur in 35-60% of patients. Staphylococcus aureus is the pathogen that causes nervous system involvement most frequently. We report a case of a 67-year-old man with infective endocarditis following a dental procedure that manifested as spondylodiscitis and multiple brain embolization, including a brain abscess that required drainage. After six weeks of treatment with broad-spectrum antibiotics and complex supportive therapy, we discharged the patient in a satisfactory mental and somatic condition. The preparation of the patient for cardiac surgery is ongoing.
- MeSH
- absces mozku diagnostické zobrazování etiologie patologie terapie MeSH
- discitida diagnostické zobrazování komplikace patologie MeSH
- echokardiografie transezofageální MeSH
- endokarditida * diagnostické zobrazování farmakoterapie komplikace patologie terapie MeSH
- extrakce zubů škodlivé účinky MeSH
- intrakraniální embolie * diagnostické zobrazování komplikace patologie MeSH
- lidé MeSH
- magnetická rezonanční tomografie MeSH
- mitrální insuficience diagnostické zobrazování etiologie farmakoterapie MeSH
- senioři MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- Publikační typ
- kazuistiky MeSH
Úvod: Tichý mozgový infarkt (silent cerebral infarction; SCI) sa považuje za rizikový faktor postupného rozvoja kognitívnej dysfunkcie, psychiatrických ochorení, vzniku CMP a skoršej mortality. Presná incidencia a prevalencia SCI nie je známa a líši sa na základe výsledkov publikovaných klinických štúdií. Cieľom našej práce bolo zistiť výskyt incidentálnych akútnych a subakútnych SCI na MR mozgu a ich objem u pacientov pred plánovanou koronárnou intervenciou, ako aj posúdiť rizikové faktory vzniku SCI. Materiál a metodika: Do štúdie boli zaradení pacienti pred elektívnou koronárnou angiografiou, angioplastikou alebo stentingom. Pred intervenciou absolvovali MR mozgu, na ktorom sa hodnotila prítomnosť akútneho a subakútneho SCI, jeho objem a vzťah jednotlivých rizikových faktorov k výskytu SCI. Zároveň sa hodnotil kognitívny deficit vo vzťahu k SCI. Výsledky: Do štúdie bolo od novembra 2015 do júla 2017 zaradených 144 pacientov (103 mužov a 41 žien). Zo 144 pacientov malo prítomný minimálne jeden akútny/subakútny SCI na MR pred koronárnou intervenciou 9 (6,3 %) pacientov. Jediným štatisticky významným rizikovým faktorom prítomnosti SCI bol vyšší výskyt prekonanej CMP/tranzitórneho ischemického ataku (TIA) v minulosti (p = 0,05). U jednej pacientky bola diagnostikovaná ipsilaterálna stenóza arteria carotis interna > 50 %. Objem mozgových ischemických ložísk bol väčší u pacientov s prekonanou CMP/TIA v anamnéze (p = 0,008). Vyšetrenie kognitívnych testov nepotvrdilo štatisticky významné rozdiely medzi pacientami s SCI a pacientami bez SCI (p > 0,05). Záver: U pacientov indikovaných k elektívnej koronárnej intervencii sa vyskytoval akútny/subakútny SCI v 6,3 %. Ako rizikový faktor prítomnosti a zároveň väčšieho objemu ischemických ložísk sa preukázala anamnéza prekonanej CMP/TIA. Štúdia nepotvrdila štatisticky významný kognitívny deficit u pacientov s SCI oproti pacientom bez SCI.
Introduction: The presence of silent cerebral infarction (SCI) might cause cognitive dysfunction, psychiatric disorders, stroke and earlier mortality. Exact incidence and prevalence of SCI is still not known, the results of previously published clinical trials vary. The aims of our study were to detect acute and subacute SCI using MRI in patients before elective coronary intervention, measure the volume of SCI and investigate the risk factors associated with SCI. Materials and methods: Patients indicated for elective coronary angiography, angioplasty or stenting were enrolled in this study. Brain MRI was performed before cardiac intervention. The presence of acute and subacute SCI was evaluated, SCI volume was measured and risk factors associated with SCI were investigated. Cognitive functions were tested and correlated with SCI. Results: Between November 2015 and July 2017, 144 patients were enrolled in the study (103 men, 41 women). At least one acute/subacute SCI was detected on MRI in 9 out of 144 (6.3%) patients before cardiac intervention. History of stroke or transient ischemic attack (TIA) was associated with a higher risk of SCI (p = 0.05). Ipsilateral internal carotid artery stenosis > 50% was diagnosed in one patient. Patients with a history of stroke/TIA had a larger volume of SCI (p = 0.008). We did not find stastistically significant differences in cognitive function tests between patients with SCI and without SCI (p > 0.05). Conclusion: Acute/subacute SCI was detected in 6.3% of patients indicated for elective coronary intervention. History of stroke or TIA was a predictor of the presence of SCI and also its volume. No correlation was found between SCI and cognitive dysfunction.
- Publikační typ
- abstrakt z konference MeSH
