Clinical Neuroradiology最新文献

Purpose: The purpose of this study is to measure the brain temperature (T_br) by using ¹H magnetic resonance spectroscopy (¹H MRS) thermometry and investigate its age and gender differences in healthy adults. The brain temperature was further compared with the body temperature (T_bo) to investigate the possible existence of brain-body temperature gradient (∆T).

Methods: A total of 80 subjects were included in this study. ¹H MRS data were collected on a 3.0T MR scanner using Point Resolved Selective Spectroscopy (PRESS) sequence. Voxels were positioned in the right frontal (RF) lobe and left frontal (LF) lobe, respectively. The temperature of each voxel was calculated by chemical shift difference (∆δ) between H₂O and NAA which was obtained by LCModel software. The average temperature of bilateral frontal lobe voxels was defined as T_br for each subject. The average forehead temperature was acquired before MR scanning, defined as T_bo, in this study. The difference between T_br and T_bo, denoted as the brain-body temperature gradient (∆T), was calculated. Age and gender characteristics of T_br, ∆T and T_bo were analyzed.

Results: T_br (38.51 ± 0.59℃) was higher than T_bo (36.47 ± 0.26℃) (P < 0.05). Negative correlations were observed between T_br and age (r = -0.49, P < 0.05) and between ∆T and age (r = -0.44, P < 0.05), whereas no correlation existed between T_bo and age (r = -0.03, P = 0.79).

Conclusion: Our observation demonstrated that the brain temperature, derived from ¹H MRS thermometry, is significantly higher than the body temperature, indicating the existence of a brain-body temperature gradient, and the brain temperature gradually decreases with age.

Background: The susceptibility vessel sign (SVS) on baseline MRI in acute ischemic stroke patients has been associated with better outcomes post-thrombectomy. This study aimed to investigate whether the presence of the SVS modifies the treatment effect of intravenous thrombolysis plus endovascular thrombectomy (IVT + EVT) versus thrombectomy alone (EVT alone).

Methods: In this secondary analysis of the SWIFT DIRECT trial, comparing IVT + EVT versus EVT alone, treatment effect and its heterogeneity were assessed with rates of pre-interventional reperfusion (eTICI 2a-3) and successful post-interventional reperfusion (eTICI of 2b-3) according to the SVS status using adjusted multivariable logistic regression. Secondary objectives were to analyze whether the presence of SVS or its individual characteristics (location, length, width, overestimation ratio, two-layered sign) were associated with outcomes.

Results: 197 of the initial 408 trial participants were included in this secondary analysis, of which 52% received IVT + EVT. SVS was present in 92% of the participants (n = 181). There was no evidence for treatment effect heterogeneity regarding the post-interventional radiological and clinical effects of IVT + EVT versus EVT alone with strata of SVS. In SVS+ participants, IVT favored pre-interventional reperfusion (aOR 7.95, 95% CI 1.42-44.46), whereas in SVS-patients, it did not (P for interaction = 0.02). The individual SVS characteristics showed no significant associations with outcomes.

Conclusion: Presence of SVS does not seem to modify the effect of IVT + EVT versus EVT alone. In SVS+ patients, IVT might improve pre-interventional reperfusion. There is insufficient evidence to recommend using SVS to inform IVT decisions prior to EVT.

Background and purpose: Endovascular thrombectomy is now the standard of care for large vessel occlusion acute ischemic stroke. However, acute stroke due to medium-vessel occlusions often result in unfavorable outcomes, and guidelines for thrombectomy are lacking. Moreover, nearly all clinical data and thrombectomy trials are based on biplane angiography systems. This study aims to compare the safety and efficacy of stroke thrombectomy procedures performed on single-plane versus biplane angiography systems in patients presenting with medium-vessel occlusions of the middle cerebral artery.

Materials and methods: This retrospective study included consecutive patients with acute ischemic stroke due to primary middle cerebral artery medium-vessel occlusions treated with thrombectomy between 7/1/2020 and 8/1/2022 at a single high-volume practice. Patients were dichotomized into those treated on single plane and biplane systems. Demographic, procedural, clinical and follow-up characteristics were compared.

Results: Among the 149 patients included, 44 underwent thrombectomy on single-plane systems, and 93 on biplane systems. No significant differences were detected in rates of good functional outcomes (mRS < 2; SP 54% vs BP 42%, p = 0.19), successful recanalization (TICI ≥ 2B; SP 91% vs BP 86%, p = 0.77), intra-procedural vascular injury (SP 0% vs BP 3%; p = 0.56), or time from groin puncture to reperfusion (SP 25 min vs BP 27 min; p = 0.97). No significant differences were detected in peri-procedural complications, or symptomatic intracerebral hemorrhage.

Conclusion: Thrombectomy for middle cerebral artery medium-vessel occlusions performed on single-plane angiography systems is as safe and efficacious as biplane procedures. Our results may have implications for increasing access to care, especially in regions with limited resources.

Purpose: Pituitary adenomas are much rarer in children than in adults. We aimed to analyze their imaging characteristics in this age group and to compare them according to the hormonal secretion. We conducted an observational monocentric retrospective study on clinical and imaging data.

Methods: We analyzed imaging features before surgery or drug treatment of pituitary adenomas in children confirmed by histopathology or hormonal secretion. We assessed tumoral signal intensity, volume and aggressiveness, and compared it according to the hormonal secretion.

Results: We included 31 children (13 lactotroph (42%), 8 corticotroph (26%), 5 somatotroph (16%), 5 plurihormonal adenomas (16%) including 1 non-secreting macroadenoma) with a median age of 13 years (range 2-16 years-old), without age or sex difference between secretion types. Lactotroph and somatotroph adenomas were larger than corticotroph adenomas (p = 0.007) and were more aggressive (p = 0.01). They also had higher signal intensity on T2-weighted images (p = 0.04). T1 signal intensity was similar between the groups on pre and post-contrast images (lower enhancement than the normal pituitary). No non-secreting micro-adenoma became clinically significant enough to lead to a pathological confirmation or specific treatment. Genetic research was conducted on 20 children, finding MEN1 mutations in 80% of the patients.

Conclusions: Pituitary adenomas in children are rare but should be considered when facing similar imaging features than in adults. Imaging characteristics may allow to suspect the hormonal secretion.

Purpose: In vitro differentiation of iodine and tantalum-based liquid embolics post-embolization can be achieved using spectral computed tomography. This study evaluates the in vivo ability of clinical photon-counting computed tomography (PCD-CT) to distinguish these embolic agents in patients undergoing endovascular treatments for cerebrovascular and spinal pathologies.

Methods: This retrospective study included 25 patients treated between April 2021 and March 2024, who underwent PCD-CT imaging post-embolization for intracranial arteriovenous malformations (AVM), dural arteriovenous fistulas (dAVF), spinal tumors, or middle meningeal artery (MMA) embolization for chronic subdural hematomas (cSDH). Imaging analysis involved iterative reconstruction, using conventional images (CI), iodine maps (IM), and virtual non-contrast (VNC) series. Two blinded neuroradiologists assessed the suppression quality of the embolic agents on a Likert scale.

Results: Of the 25 patients, 22 underwent intracranial and 3 spinal embolizations. The differentiation between iodine and tantalum-based embolics achieved 92% accuracy for reader 1 and 88% for reader 2, with a Cohen's kappa coefficient of 0.92 indicating high inter-reader agreement. Iodine-based agents were moderately suppressed, whereas tantalum-based agents exhibited superior suppression. Errors arose from mistaking suppressed platinum coils for tantalum-based embolics. Hemorrhage detection accuracy was high, with a Cohen's kappa of 0.92.

Conclusions: PCD-CT effectively differentiates between iodine- and tantalum-based embolics in vivo, demonstrating high diagnostic accuracy and inter-reader reliability. This capability facilitates improved post-procedural assessment and may enhance the management of endovascularly treated patients by reducing imaging artifacts and aiding in hemorrhage detection.

Purpose: The twig-like middle cerebral artery (TL-MCA) is a vascular anomaly reconstituting the MCA-M1 segment through a plexiform arterial network. Most patients with TL-MCA have a high risk of hemorrhage, but the associated vascular anatomical risk factors are poorly understood. To investigate the angioarchitecture of TL-MCA in detail to distinguish the radiological differences between hemorrhagic and non-hemorrhagic onset.

Methods: 3214 cerebral digital subtraction angiography procedures were performed, and patients with TL-MCA were included and their clinical and anatomical characteristics were retrospectively reviewed.

Results: 12 patients (median age 47 years, and 9 women) with TL-MCA were included (incidence rate, 0.37%). Among them, four had hemorrhagic stroke, five had ischemic stroke, and three had no symptoms. Perforator anastomoses were identified in five patients (41.6%). Among the four patients with intraparenchymal hemorrhage (IPH), three had looping lenticulostriate artery (LSA) anastomoses and one had non-looping LSA anastomosis. One looping LSA anastomosis was discovered fortuitously in a patient explored for headaches. The recurrent artery of Heubner, which is responsible for the plexiform arterial network, was identified in 10 patients (83.3%). Angiographic evolutions (de novo TL-MCA) were observed in three patients, and one patient experienced a clinical evolution of a TL-MCA with non-looping LSA anastomosis, progressing from no symptoms to IPH.

Conclusions: In this small series, looping LSA anastomoses were mainly observed in TL-MCA with IPH. This anatomical disposition could represent a potential risk factor. The TL-MCA always affects the subpallial segment of the MCA-M1, and may be a subpallium-related pathology.

Purpose: Myocardial injury, indicated by an elevation of high-sensitive cardiac Troponin (hs-cTnT), is a frequent stroke-related complication. Most studies investigated patients with ischemic stroke, but only little is known about its occurrence in patients with intracerebral hemorrhage (ICH). This study aimed to assess the frequency, predictors, and implications of myocardial injury in ICH patients.

Methods: Our retrospective analysis included 322 ICH patients. We defined myocardial injury as an elevation of hs-cTnT above the 99th percentile (i.e. 14 ng/L). Acute myocardial injury was defined as either a changing pattern of > 50% within 24 h or an excessive elevation of initial hs-cTnT (> 52 ng/L). 3D brain scans were assessed for ICH visually and quantitatively by a deep learning algorithm. Multiple regression models and Voxel-based Lesion-Symptom Mapping (VLSM) were applied.

Results: 63.0% (203/322) of patients presented with myocardial injury, which was associated with more severe strokes and worse outcomes during the in-hospital phase (P < 0.01). Acute myocardial injury occurred in 24.5% (79/322) of patients. The only imaging finding associated with acute myocardial injury was midline shift (69.8% vs. 44.6% for normal or stable hs-cTnT, P < 0.01), which also independently predicted it (odds ratio 3.29, confidence interval 1.38-7.87, P < 0.01). In contrast, VLSM did not identify any specific brain region significantly associated with acute myocardial injury. Acute myocardial injury did not correlate with preexisting cardiac diseases; however, the frequency of adverse cardiac events was higher in the acute myocardial injury group (11.4% vs. 4.1% in patients with normal and/or stable patterns of hs-cTnT, P < 0.05).

Conclusion: Myocardial injury occurs frequently in ICH and is linked to poor outcomes. Acute myocardial injury primarily correlates to space-occupying effects of ICH but is less dependent on premorbid cardiac status. Nonetheless, it is associated with a higher rate of adverse cardiac events.

Background: Cardiovascular risk management is beneficial, but stringent glycemic control does not prevent the progression of distal sensorimotor polyneuropathy (DSPN). Persistent hyperglycemia-induced alterations and cardiovascular factors may contribute to diabetes-associated nerve damage. This study aimed to evaluate the correlation between skin auto-fluorescence (sAF), an indicator of dermal advanced glycation end-product (AGE) accumulations, cardiovascular risk, and changes in peripheral nerve integrity.

Methods: Sixty-two individuals with type 2 diabetes (T2D) (20 women and 42 men), including 29 diagnosed with DSPN (7 women and 22 men), and 10 healthy controls (HC) underwent diffusion tensor MR imaging of the sciatic nerve to assess fractional anisotropy (FA), an indicator of nerve structural integrity. sAF measurements were combined with clinical, serological, and electrophysiological evaluations. Arterial stiffness was assessed via pulse wave velocity (PWV).

Results: sAF (HC 2.1 ± 0.25 AU, nDSPN 2.3 ± 0.47, DSPN 2.6 ± 0.43; p = 0.005) was higher in individuals with DSPN compared to HC (p = 0.010) and individuals without DSPN (p = 0.035). Within the group of T2D FA correlated negatively with sAF (r = -0.49, p < 0.001), PWV (r = -0.40, p = 0.009) and high-sensitivity troponin T (hsTNT), a marker of microvascular damage (r = -0.39, p < 0.001). In DSPN, sAF correlated positively with hsTNT (r = 0.58, p = 0.005) and with PWV (r = 0.52, p = 0.007), the sciatic nerve's FA correlated negatively with PWV (r = -0.47, p = 0.010).

Conclusions: This study is the first to show close correlations between reduced peripheral nerve integrity and both intradermal AGE deposition and arterial stiffness in individuals with T2D. These findings highlight a mechanistic link between glycation-related vascular injury and neuronal damage emphasizing the importance of cardiovascular risk management in preventing DSPN.

Background: Hypertension (HTN) is a prevalent cardiovascular condition associated with cognitive impairments, including memory deficits and attention lapses. Understanding the neural mechanisms underlying HTN-related cognitive dysfunction is crucial for optimizing treatment strategies.

Method: A systematic review was conducted to explore the impact of antihypertensive medications on cognition, focusing on memory, attention, and emotion processing using functional magnetic resonance imaging (fMRI). Searches were performed in PubMed and Scopus up to March 10, 2024, with no language restrictions.

Results: A total of 108 articles were identified, of which 12 systematic reviews and meta-analyses met the inclusion criteria. Included studies investigated various antihypertensive drugs, including losartan, propranolol, spironolactone, and telmisartan, and their effects on cognitive processes. Losartan improved negative memory encoding and facilitated fear extinction via hippocampal and prefrontal modulation. Propranolol disrupted fear reconsolidation and reduced emotional memory retrieval, affecting the amygdala and hippocampus. Spironolactone prevented stress-induced memory shifts in the amygdala. Findings indicated distinct impacts of these medications on memory encoding, fear extinction, and stress-induced memory modulation, as evidenced by alterations in neural activity patterns observed on fMRI.

Conclusion: Antihypertensive medications, such as losartan and propranolol, demonstrate potential in modulating memory, fear-related memory reconsolidation, and stress-induced memory modulation, highlighting their therapeutic implications for conditions like posttraumatic stress disorder (PTSD) and anxiety disorders. This review underscores the importance of fMRI studies in elucidating the neural correlates of HTN-related cognitive impairments and optimizing treatment approaches.

Purpose: Magnetic Resonance Imaging based brain segmentation and volumetry has become an important tool in clinical routine and research. However the impact of the used hardware is only barely investigated. This study aims to assess the influence of scanner manufacturer, field strength and head-coil on volumetry results.

Methods: 10 healthy subjects (27.4 ± 1.71 years) were prospectively examined in a Philips Achieva 1.5T, Philips Ingenia CX 3T, Siemens MAGNETOM Aera 1.5T and Siemens MAGNETOM Vida 3T, the latter equipped with three different head coils, within one day. Brain volumetry of the whole brain, total white and grey matter, the cortical grey matter of the supratentorial lobes as well as regions important for the differentiation of neurodegenerative diseases of the dementia and movement disorder spectrum and the ventricular system was performed using the CE-certified software mdbrain by mediaire (Berlin, Germany). Both raw volumetry results and percentile allocation provided by the software were analysed.

Results: This study reveals significantly different volumetry results for all examined brain regions beside the ventricular system between the different MRI devices but comparable results between the different head coils. When examining the percentile allocation provided by used software, the Intraclass-Correlation-Coefficient (ICC) values were even lower than the raw volume ICC values ranging from poor to excellent correlation.

Conclusion: The present study reveals highly relevant results that need to be considered both in clinical routine when analysing follow-up examinations from different scanner types and clinical research, especially when planning longitudinal and/or multicentre studies.