Background: Amnestic mild cognitive impairment (aMCI) is a transitional state between normal aging and dementia, and identifying early biomarkers is crucial for disease detection and intervention. Functional magnetic resonance imaging (fMRI) has the potential to identify changes in neural activity in MCI. Methods: We investigated neural activity changes in the visual network of the aMCI patients (n:20) and healthy persons (n:17) using resting‐state fMRI and visual oddball task fMRI. We used independent component analysis to identify regions of interest and compared the activity between groups using a false discovery rate correction. Results: Resting‐state fMRI revealed increased activity in the areas that have functional connectivity with the visual network, including the right superior and inferior lateral occipital cortex, the right angular gyrus and the temporo‐occipital part of the right middle temporal gyrus (p‐FDR = 0.008) and decreased activity in the bilateral thalamus and caudate nuclei, which are part of the frontoparietal network in the aMCI group (p‐FDR = 0.002). In the visual oddball task fMRI, decreased activity was found in the right frontal pole, the right frontal orbital cortex, the left superior parietal lobule, the right postcentral gyrus, the right posterior part of the supramarginal gyrus, the right superior part of the lateral occipital cortex, and the right angular gyrus in the aMCI group. Conclusion: Our results suggest the alterations in the visual network are present in aMCI patients, both during resting‐state and task‐based fMRI. These changes may represent early biomarkers of aMCI and highlight the importance of assessing visual processing in cognitive impairment. However, future studies with larger sample sizes and longitudinal designs are needed to confirm these findings.
Bilateral pedicle fracture is an extremely rare entity and few cases have been reported in literature. A case of bilateral multi-level pedicle fractures involving four lumbar vertebrae is being presented. Bilateral pedicle stress fracture at L1 - L4 was observed in a 61-year-old woman presented with low back pain. There was no any predisposing factor like trauma, spinal surgery, smoking or alcohol consumption except mild osteoporosis and bisphosphonate usage in the patient's medical history. We are unable to determine whether the fractures are related to osteoporosis or bisphosphonate therapy but these are the only remaining suspected reasons in the present case. Further studies are required to define the effect of bisphosphonates usage on vertebral segments.
Background and Objectives: The pathophysiology of mild cognitive impairment in Parkinson’s disease (PD-MCI) is still not fully elucidated. It has been shown in a few studies in the literature that volume loss in the occipital, parietal and frontal cortices and atrophy in the hippocampus of PD-MCI patients can occur in the early stages of PD. The aim of this study was to evaluate the relationship between gray and white matter volumes and different neuropsychological tests and volumetric magnetic resonance imaging parameters in patients with mild cognitive impairment in Parkinson’s disease (PD-MCI). Materials and Methods: Twenty-six PD-MCI and twenty-six healthy elderly (HC) were included in this study. Results: We found that Mini Mental State Examination, Trail Making Test Part A, Clock Drawing Test, Benton Line Judgment Orientation Test and pentagon figure-copying scores were impaired in PD-MCI patients due to the decrease in brain volumes. Conclusions: Our study revealed that among PD-MCI patients, there was a more noticeable decline in White matter volume (WMV) based on volumetric Magnetic Resonance Imaging (MRI) compared to the localized loss of GMV. We think that these abnormal neuropsychological tests in PD-MCI patients can be used as pretests in the evaluation of the stage of transition to dementia.
12 June 2024 in TURKISH JOURNAL OF MEDICAL SCIENCES
Background/aim: Amnestic mild cognitive impairment (aMCI) is a risk factor for dementia, and thus, it is of interest to enlighten specific brain atrophy patterns in aMCI patients. We aim to define the longitudinal atrophy pattern in subcortical structures and its effect on cognition in patients with aMCI.Materials and methods: Twenty patients with aMCI and 20 demographically matched healthy controls with baseline and longitudinal structural magnetic resonance imaging scans and neuropsychological assessments were studied. The algorithm FIRST (FMRIB’s integrated registration and segmentation tool) was used to obtain volumes of subcortical structures (thalamus, putamen, caudate nucleus, nucleus accumbens, globus pallidus, hippocampus, and amygdala). Correlations between volumes and cognitive performance were assessed.Results: Compared with healthy controls, aMCI demonstrated subcortical atrophies in the hippocampus (p = 0.001), nucleus accumbens (p = 0.003), and thalamus (p = 0.003) at baseline. Significant associations were found for the baseline volumes of the thalamus, nucleus accumbens, and hippocampus with memory, the thalamus with visuospatial skills.Conclusion: aMCI demonstrated subcortical atrophies associated with cognitive deficits. The thalamus, nucleus accumbens, and hippocampus may provide additional diagnostic information for aMCI.
Giriş: Bilgisayarlı tomografi (BT) cihazları teknolojik gelişmeleri ile birlikte hastalıkların tanısında her geçen gün daha fazla kullanılmakta ve bunun sonucu olarak hasta dozlarında büyük bir artışa neden olmaktadır. Klinik olarak BT çekimleri çok yararlı olmasına rağmen, radyasyon dozu ve bunun meydana getirebileceği olası kanser riski geleceğin en büyük problemi olarak değerlendirilmektedir. Bu nedenle BT taramalarında, görüntü kalitesinden ödün vermeden görüntüleme parametrelerini kontrol ederek hasta dozlarının düşürülmesi temel ilke olmalıdır. Amaç: Bu çalışmanın amacı, baş-boyun BT anjiyografi çekimlerinde otomatik tüp akım modülasyon (OTAM) sisteminin kullanılmasının hasta dozlarının azaltılması ve görüntü kalitesi üzerindeki etkilerini araştırmaktır. Yöntemler: Serebrovasküler hastalık nedeniyle izlenen 23 hasta bu çalışmaya dahil edilmiştir. Sabit tüp akımı (mAs) kullanılarak yapılmış rutin baş boyun BT anjiyografi taramasının takibi için gelen hastaya tüm görüntüleme parametreleri sabit kalmak kaydıyla sadece otomatik tüp akımı modülasyonu tekniği kullanılarak tetkik gerçekleştirildi. Her iki yöntemle elde edilen veriler, hem hastaya verilen doz hem de görüntü kalitesi açısından değerlendirildi ve karşılaştırıldı. Bulgular: Akım modülasyonu sistemi kullanıldığında etkin doz değerinde %35’lik bir azalma gözlendi. Objektif değerlendirme için baş-boyun kısmında belirlenen 3 farklı anatomik bölgede sinyal-gürültü oranı (SNR) değerleri için beyin sapında %49, omuz bölgesinde %25, serebellumda ise %42 lik bir azalma olduğu bulundu. Subjektif değerlendirmede ise akım modülasyon sistemi kullanılarak elde edilen görüntüler 2 radyolog tarafından incelendi ve 0-4 arasındaki puanlama sonucunda bu görüntülerin ortalama puanı 2,2 olarak bulundu. Sonuç: Baş-boyun anjiyo BT incelmelerinde otomatik akım modülasyonu ile radyasyon dozlarında belirgin azalma elde edilmiş, SNR nin azalmasına rağmen klinik açıdan tanısal kayıp olmadığı görülmüştür. Hasta dozlarının azaltılması ve tanısal açıdan dezavantaj oluşturmaması için uygun kriterlerde kullanılacak OTAM tekniğinin nöroanjiyo çekimlerinde rutin uygulamaya girmesi kesinlikle önerilmektedir.