Marek Sasiadek

Multimodal imaging in diagnosis of Alzheimer's disease and amnestic mild cognitive impairment: value of magnetic resonance spectroscopy, perfusion, and diffusion tensor imaging of the posterior cingulate region.

The purpose of this study was to assess metabolic, perfusion, and microstructural changes within the posterior cingulate area in patients with Alzheimers disease (AD) and amnestic mild cognitive impairment (aMCI) using advanced MR techniques such as: spectroscopy (MRS), perfusion weighted imaging (PWI), and diffusion tensor imaging (DTI). Thirty patients with AD (mean age 71.5 y, MMSE 18), 23 with aMCI (mean age 66 y, MMSE 27.4), and 15 age-matched normal controls (mean age 69 y, MMSE 29.5) underwent conventional MRI followed by MRS, PWI, and DTI on 1.5 Tesla MR unit. Several metabolite ratios (N-acetylaspartate [NAA]/creatine [Cr], choline [Ch]/Cr, myoinositol [mI]/Cr, mI/NAA, mI/Cho) as well as parameters of cerebral blood volume relative to cerebellum and fractional anisotropy were obtained in the posterior cingulate region. The above parameters were correlated with the results of neuropsychological tests. AD patients showed significant abnormalities in all evaluated parameters while subjects with aMCI showed only perfusion and diffusion changes in the posterior cingulate area. Only PWI and DTI measurements revealed significant differences among the three evaluated subject groups. DTI, PWI, and MRS results showed significant correlations with neuropsychological tests. DTI changes correlated with both PWI and MRS abnormalities. Of neuroimaging methods, DTI revealed the highest accuracy in diagnosis of AD and aMCI (0.95, 0.79) followed by PWI (0.87, 0.67) and MRS (0.82, 0.47), respectively. In conclusion, AD is a complex pathology regarding both grey and white matter. DTI seems to be the most useful imaging modality to distinguish between AD, aMCI, and control group, followed by PWI and MRS.

Does perfusion CT enable differentiating Alzheimer's disease from vascular dementia and mixed dementia? A preliminary report

UNLABELLED The purpose of the study was to evaluate the usefulness of perfusion CT (pCT) in differentiating Alzheimers disease (AD) from vascular dementia (VaD) and mixed dementia (MixD). pCT was performed in 41 patients (mean age, 68.3 years): 24 with AD, 8 with VaD, and 9 with MixD. Regional perfusion parameters (rCBF, rCBV, and rMTT) were calculated from 31 ROIs in the grey and white matter of the frontal and temporal lobes, basal ganglia, and internal capsules bilaterally. The obtained data for the subgroups of AD, VaD, and MixD patients were compared statistically. CONCLUSIONS On the basis of rCBF and rCBV values, pCT may be a valuable method of distinguishing between AD and VaD but it seems to be of little significance in differentiating MixD from VaD and of no usefulness in distinguishing between AD and MixD.

Immunoglobulin D myeloma – Problems with diagnosing and staging (own experience and literature review)

Immunoglobulin D (IgD) myeloma is a rare disease accounting for about 2% of all myelomas. The distinctive features are the predominant occurrence in males and young patients, short survival time, uncertain appearance of M-component in serum electrophoresis, predominance of lambda light chains, frequent renal impairment, hypercalcemia and amyloidosis. The aim of the present study was to show diagnostic difficulties resulting from a variety of non-specific initial symptoms and laboratory findings as well as to compare the staging system proposed by Durie and Salmon with the new risk grouping by Shimamoto. Case histories of 7 patients were analyzed retrospectively. Five of them were diagnosed as IgD multiple myeloma (IgD MM), 1 as non-secretory IgD myeloma and 1 as solitary bone IgD plasmocytoma that evolved to an IgD MM. All patients were staged according to the Durie and Salmon classification and the new risk grouping by Shimamoto. We report diagnostic problems with IgD myeloma in our patients, with special emphasis on non-specific rheumatoidal and neurological symptoms in 1 case. There was a very good correlation of the Japanese classification with the severity of the disease and the risk of death. In conclusion, the initial symptoms of IgD myeloma can be very misleading. Wide differential diagnosis, including autoimmunological disorders of the connective tissue, is necessary. The new Japanese risk grouping seems to be of greater prognostic significance for IgD myeloma than the Durie and Salmon staging system.

Evaluation of the Posterior Cingulate Region with FDG-PET and Advanced MR Techniques in Patients with Amnestic Mild Cognitive Impairment: Comparison of the Methods

BACKGROUND The posterior cingulate region is an area of the earliest pathological changes in amnestic mild cognitive impairment (aMCI). The utility of FDG-PET imaging in dementia is already well established. OBJECTIVES The aim of the study was to compare FDG-PET with advanced MR measurements: MR spectroscopy (MRS), perfusion weighted imaging (PWI), and diffusion tensor imaging (DTI) within the posterior cingulate region in patients with aMCI. METHODS Fifty-five patients diagnosed with aMCI (66.5 y) and 20 age-matched controls (69 y) underwent MR examination including MRS, PWI, and DTI followed by FDG-PET scanning. Values of MRS metabolite ratios (NAA/Cr, Cho/Cr, mI/Cr), PWI cerebral blood volume (rCBV), and DTI fractional anisotropy (FA) were compared to the FDG-PET rates of glucose metabolism. RESULTS Compared to controls, aMCI patients showed significant (p < 0.05) glucose hypometabolism, and lower rCBV and FA values. FDG-PET results correlated significantly with rCBV values. Compared to FDG-PET, PWI showed similar and DTI greater accuracy in distinguishing aMCI from controls. According to FDG-PET findings, two groups of aMCI patients were established: those with lower (PET-positive) and normal (PET-negative) glucose uptake. PET-positive aMCI subjects showed normal MRS findings, lower rCBV and FA values, while PET-negative patients revealed normal MRS and PWI results but significantly lower FA values. CONCLUSIONS Advanced MR techniques such as PWI and particularly DTI may be regarded as competitive techniques to FDG-PET. DTI was the only method to show alterations in aMCI patients with normal FDG-PET, PWI, and MRS findings. DTI seems to be a very sensitive biomarker of early degeneration in aMCI.

A new case of cerebro-facio-thoracic dysplasia in a 3-year-old girl with short stature and hypothyroidism.

Introduction Cerebro-facio-thoracic dysplasia (CFTD) is a genetic syndrome of unknown cause, characterized by typical facial dysmorphic features, and psychomotor and intellectual disability, along with brain malformations as well as multiple skeletal defects, including rib and vertebral abnormalities. Autosomal recessive inheritance has been suggested (Pascual-Castroviejo et al., 1975; Philip, 1992; Guion-Almeida et al., 1996; Rufo-Campos et al., 2004; Cilliers et al., 2007).

Novel COL4A1 mutation in an infant with severe dysmorphic syndrome with schizencephaly, periventricular calcifications, and cataract resembling congenital infection.

BACKGROUND A clinical case is described of growth retardation, severe developmental delay, facial dysmorphic features with microcephaly, as well as congenital cataract, schizencephaly, periventricular calcifications, and epilepsy. METHODS TORCH infection was suspected, but all tests for toxoplasmosis, rubella, cytomegalovirus, and herpes simplex virus were negative for the child and her mother; however, an increased level of antibodies against parvovirus B19 was detected in the proband. RESULTS Chromosomal analysis and array-CGH showed no aberration. Target capture sequencing for COL4A1 and COL4A2 revealed a de novo COL4A1 mutation (c.2123G>T [p.Gly708Val]). The mutation occurred at a highly conserved Gly residue in the Gly-X-Y repeat of the collagen triple helical domain, suggesting that these mutations may alter the collagen IV α1α1α2 heterotrimers. The mutation was predicted to be damaging. CONCLUSION We suggest that COL4A1 testing should be considered in patients with schizencephaly as well as with phenotype suggesting TORCH infection without any proven etiological factors.

Are T2-weighted images more useful than T1-weighted contrast-enhanced images in assessment of postoperative sella and parasellar region?

Summary Background The proper diagnosis and management of patients after surgery for pituitary tumors are of great importance in clinical practice. The purpose of this study was to investigate the magnetic resonance features of the postoperative sella with fast spin echo T2-weighted imaging and to evaluate the benefits of this sequence compared to the classically performed contrast-enhanced T1-weighted imaging at 1.5T unit. Material/Methods The study group consisted of 101 patients who underwent resection of pituitary tumors. There were 58 women (57.4%), aged 22 to 75 (mean age, 52.67 years) and 43 men (42.6%), aged 21 to 79 (mean age, 49 years). In all patients preoperative and multiple postoperative MR studies were performed. Post-contrast T1 and pre-contrast T2 images were interpreted by 2 independent readers (neuroradiologists). Results Contrast-enhanced T1-weighted imaging was significantly superior to T2-weighted imaging in assessment of infundibulum (p<0.05). There was no statistically significant difference for each of readers between T1- and T2-weighted images regarding to the following features: visualization of residual pituitary gland (p=0.062 and p=0.368), contours of pituitary (p=0.959 and p=0.265), optic chiasm (p=0.294 and p=0.843), and visualization of presence of residual tumor (p=0.204 and p=0.169). T2-weighted images were significantly superior to contrast-enhanced T1-weighted imaging with regard to visualization of contours of residual tumors (p<0.05). Conclusions T2-weighted images may help to discriminate tumorous from non-tumorous involvement of the postoperative sella and the sphenoid sinus. T2-weighted images are also very useful for a long time after the resection in the postoperative evaluation of the implanted muscle with fascia.

Computer-Interactive Methods of Brain Cortical Evaluation

The subject of the paper is the evaluation of a brain atrophy depending on computed tomography (CT) images. There are two computer aided methods under investigation. The first one is a semi-automatic volumetric method, the second is a fully automatic one and depends on the fractal dimension. Results of the experiment with 68 patients show that both methods are able to estimate the brain atrophy very similarly to the evaluation made by expert radiologist with the coefficient of correlation in the range of 0.7-0.9. The great advantage of the automatic method comparing to volumetric method is generating results in a very short time, that counts in ordinary clinical practice and could be used to experiment with huge patient groups.

Statistical, Morphometric, Anatomical Shape Model (Atlas) of Calcaneus

The aim was to develop a morphometric and anatomically accurate atlas (statistical shape model) of calcaneus. The model is based on 18 left foot and 18 right foot computed tomography studies of 28 male individuals aged from 17 to 62 years, with no known foot pathology. A procedure for automatic atlas included extraction and identification of common features, averaging feature position, obtaining mean geometry, mathematical shape description and variability analysis. Expert manual assistance was included for the model to fulfil the accuracy sought by medical professionals. The proposed for the first time statistical shape model of the calcaneus could be of value in many orthopaedic applications including providing support in diagnosing pathological lesions, pre-operative planning, classification and treatment of calcaneus fractures as well as for the development of future implant procedures.

On automation of brain CT image analysis

During recent years a number of medical diagnosis support systems have been presented. Such systems are important from medical point of view, because they aid physicians in their daily work. Some of those systems, like Computed tomography support systems (CT) rely on image data analysis, making it an interesting research topic from pattern recognition point of view. The paper presents a practical realization of a medical support system, including segmentation, feature extraction and decision processes. Various techniques are used within the system: fuzzy logic, shape descriptors, classifiers and automatic image annotation framework. Series of 2D CT images are an input of the system. As a result, a patientpsilas diagnosis is presented.