Prasun Dastidar

Targeted exercises against hip fragility

SummaryCompared to high-impact exercises, moderate-magnitude impacts from odd-loading directions have similar ability to thicken vulnerable cortical regions of the femoral neck. Since odd-impact exercises are mechanically less demanding to the body, this type of exercise can provide a reasonable basis for devising feasible, targeted bone training against hip fragility.IntroductionRegional cortical thinning at the femoral neck is associated with hip fragility. Here, we investigated whether exercises involving high-magnitude impacts, moderate-magnitude impacts from odd directions, high-magnitude muscle forces, low-magnitude impacts at high repetition rate, or non-impact muscle forces at high repetition rate were associated with thicker femoral neck cortex.MethodsUsing three-dimensional magnetic resonance imaging, we scanned the proximal femur of 91 female athletes, representing the above-mentioned five exercise-loadings, and 20 referents. Cortical thickness at the inferior, anterior, superior, and posterior regions of the femoral neck was evaluated. Between-group differences were analyzed with ANCOVA.ResultsFor the inferior cortical thickness, only the high-impact group differed significantly (~60%, p = 0.012) from the reference group, while for the anterior cortex, both the high-impact and odd-impact groups differed (~20%, p = 0.042 and p = 0.044, respectively). Also, the posterior cortex was ~20% thicker (p = 0.014 and p = 0.006, respectively) in these two groups.ConclusionsOdd-impact exercise-loading was associated, similar to high-impact exercise-loading, with ~20% thicker cortex around the femoral neck. Since odd-impact exercises are mechanically less demanding to the body than high-impact exercises, it is argued that this type of bone training would offer a feasible basis for targeted exercise-based prevention of hip fragility.

Cerebral MRI abnormalities and their association with neuropsychiatric manifestations in SLE: a population‐based study

Objective: To evaluate the volumetric brain magnetic resonance imaging (MRI) findings in a population‐based sample of systemic lupus erythematosus (SLE) patients and to detect a possible relationship between cerebral MRI abnormalities and specific neuropsychiatric (NP) manifestations. Methods: The study population consisted of patients with SLE (n = 43) in Pirkanmaa Health Care District, Finland and of a sex‐ and age‐stratified reference group from the general population (n = 43). In addition to a clinical neurological investigation, all subjects received a detailed neuropsychological assessment and an MRI study. Volumetric measures of cerebral atrophy as well as T1‐ and T2‐weighted lesions were obtained. SLE activity was assessed by the European Consensus Lupus Activity Measure (ECLAM) index, and accumulated NP abnormalities were measured by the Systemic Lupus International Collaborating Clinics (SLICC) damage index. A cumulative lifetime dose of glucocorticoids was determined from the patientrecords. Results: Compared with controls, SLE patients had increased volumes of both T1‐ and T2‐weighted lesions (p = 0.019 and p<0.0001, respectively) and increased cerebral atrophy (p<0.001). All the measured MRI parameters were statistically significantly higher in NPSLE than in non‐NPSLE patients. In SLE patients, cerebral atrophy was associated with cognitive dysfunction, epileptic seizures, and cerebrovascular disease; T1‐weighted lesions were associated with epileptic seizures and T2‐weighted lesions with cognitive dysfunction. All MRI parameters correlated significantly with the SLICC index but not with the ECLAM index. A positive correlation was found between a cumulative dose of glucocorticoids and cerebral atrophy in SLE patients. Conclusion: MRI abnormalities, including brain atrophy and T1‐ and T2‐weighted lesions, are significantly more common in patients with SLE than in the general population and they are related to specific NP manifestations. Our findings also provide support for the organic aetiology of cognitive dysfunction in SLE.

Persistent symptoms in mild to moderate traumatic brain injury associated with executive dysfunction

In order to improve detection of subtle cognitive dysfunction and to shed light on the etiology of persistent symptoms after mild-to-moderate traumatic brain injury (TBI), we employed an experimental executive reaction time (RT) test, standardized neuropsychological tests, and diffusion tensor imaging (DTI). The Executive RT-Test, an Executive Composite Score from standardized neuropsychological tests, and DTI-indices in the midbrain differentiated between patients with persistent symptoms from those fully recovered after mild-to-moderate TBI. We suggest that persistent symptoms in mild-to-moderate TBI may reflect disrupted fronto-striatal network involved in executive functioning, and the Executive RT-Test provides an objective and novel method to detect it.

Clinical significance of glutamic acid decarboxylase antibodies in patients with epilepsy.

Purpose:  Glutamic acid decarboxylase antibodies (GADAs) have been detected in patients with epilepsy, but the clinical determinants of epilepsy associated with GADA have not been defined.

Characterization of breast cancer types by texture analysis of magnetic resonance images.

RATIONALE AND OBJECTIVES This novel study aims to investigate texture parameters in distinguishing healthy breast tissue and breast cancer in breast magnetic resonance imaging (MRI). A specific aim was to identify possible differences in the texture characteristics of histological types (lobular and ductal) of invasive breast cancer and to determine the value of these differences for computer-assisted lesion classification. MATERIALS AND METHODS Twenty patients (mean age 50.6 + or - SD 10.6; range 37-70 years), with histopathologically proven invasive breast cancer (10 lobular and 10 ductal) were included in this preliminary study. The median MRI lesion size was 25 mm (range, 7-60 mm). The selected T1-weighted precontrast, post-contrast, and subtracted images were analyzed and classified with texture analysis (TA) software MaZda and additional statistical tests were used for testing the parameters separability. RESULTS All classification methods employed were able to differentiate between cancer and healthy breast tissue and also invasive lobular and ductal carcinoma with classification accuracy varying between 80% and 100%, depending on the used imaging series and the type of region of interest. We found several parameters to be significantly different between the regions of interest studied. The co-occurrence matrix based parameters proved to be superior to other texture parameters used. CONCLUSIONS The results of this study indicate that MRI TA differentiates breast cancer from normal tissue and may be able to distinguish between two histological types of breast cancer providing more accurate characterization of breast lesions thereby offering a new tool for radiological analysis of breast MRI.

Reversible posterior leukoencephalopathy after combination chemotherapy.

Abstract We describe a young woman with Burkitts lymphoma, treated with intravenous adriamycine and cyclophosphamide and intrathecal cytarabine. She developed a reversible posterior leukoencephalopathy syndrome (RPLS) with typical MRI findings. Diffusion-weighted images during the first days after the onset of symptoms predicted a small irreversible lesion in the frontal lobe, verified on T2-weighted images 1 month later. The patient showed full recovery after high-dose steroid treatment.

Diffusion-weighted MRI in early chemotherapy response evaluation of patients with diffuse large B-cell lymphoma – a pilot study: comparison with 2-deoxy-2-fluoro- D-glucose-positron emission tomography/computed tomography

To determine the feasibility of diffusion‐weighted MRI (DWI) in the evaluation of the early chemotherapeutic response in patients with aggressive non‐Hodgkins lymphoma (NHL), eight patients with histologically proven diffuse large B‐cell lymphoma were imaged by MRI, including DWI, and positron emission tomography/computed tomography (PET/CT) before treatment (E1), and after 1 week (E2) and two cycles (E3) of chemotherapy. In all patients, whole‐body screening using T1‐ and T2‐weighted images in the coronal plane was performed. To quantitatively evaluate the chemotherapeutic response, axial images including DWI were acquired. Apparent diffusion coefficient (ADC) maps were reconstructed, and the ADC value of the tumor was measured. In addition, the tumor volume was estimated on axial T2‐weighted images. The maximum standardized uptake value (SUVmax) and active tumor volume were measured on fused PET/CT images. Lymphomas showed high signal intensity on DW images and low signal intensity on ADC maps, except for necrotic foci. The mean pre‐therapy ADC was 0.71 × 10−3 mm2/s; it increased by 77% at E2 (p < 0.05) and 24% more at E3 (insignificant); the total increase was 106% (p < 0.05). The mean tumor volume by MRI was 276 mL at baseline; it decreased by 58% at E2 (p < 0.05) and 65% more at E3 (p < 0.05), giving a total decrease of 84% (p < 0.05). All the imaged pre‐therapy tumors were strongly positive on PET/CT, with a mean SUVmax of 20. The SUVmax decreased by 60% at E2 (p < 0.05) and 59% more at E3 (p < 0.05), giving a total decrease of 83% (p < 0.05). The active tumor burden decreased by 66% at E2 (p < 0.05). At baseline, both central and peripheral tumor ADC values correlated inversely with SUVmax (p < 0.05), and also correlated inversely with active tumor burden on PET/CT and with tumor volume on MRI at E2 (p < 0.05). In conclusion, the results of DWI in combination with whole‐body MRI were comparable with those of integrated PET/CT. Copyright

Volumes of brain atrophy and plaques correlated with neurological disability in secondary progressive multiple sclerosis

The objectives of the present study was to correlate the segmented magnetic resonance imaging (MRI) volumes of intracranial cerebrospinal fluid (CSF) spaces (expressing the extent of brain atrophy) and cerebral plaques with the neurological disability in secondary progressive multiple sclerosis (MS). Earlier studies have mainly correlated MS plaques and neurological disability measured by expanded disability status scale (EDSS). The data on the association between brain atrophy and EDSS or regional functional scoring scale (RFSS) are very limited. We measured the volumes of intracranial CSF spaces in 28 patients with secondary progressive MS using MRI, and semiautomatic segmentation software. The volumes of T1-weighted hypointense and T2-weighted hyperintense MS plaques were also measured. In multiple regression analysis, increasing volumes of total (P=0.006) and relative (P=0.005) intracranial CSF spaces were significantly associated with worsening neurological disability as expressed by EDSS. No associations were found between these intracranial CSF space volumes and total RFSS scores. The mean volume of T2-weighted plaques showed a tendency to associate with total RFSS score (r=0.40, P=0.03), but no correlations were detected between T1- or T2-weighted plaque volumes and EDSS. The application of a new segmentation technique in quantifying intracranial cerebrospinal fluid spaces allowed an exact and sensitive way of assessing brain atrophy. The associations between brain atrophy and neurological disability expressed by EDSS suggests that the effect of MS therapies should be evaluated by measurement of brain atrophy.

Outcome from Complicated versus Uncomplicated Mild Traumatic Brain Injury

Objective. To compare acute outcome following complicated versus uncomplicated mild traumatic brain injury (MTBI) using neurocognitive and self-report measures. Method. Participants were 47 patients who presented to the emergency department of Tampere University Hospital, Finland. All completed MRI scanning, self-report measures, and neurocognitive testing at 3-4 weeks after injury. Participants were classified into the complicated MTBI or uncomplicated MTBI group based on the presence/absence of intracranial abnormality on day-of-injury CT scan or 3-4 week MRI scan. Results. There was a large statistically significant difference in time to return to work between groups. The patients with uncomplicated MTBIs had a median of 6.0 days (IQR = 0.75–14.75, range = 0–77) off work compared to a median of 36 days (IQR = 13.5–53, range = 3–315) for the complicated group. There were no significant differences between groups for any of the neurocognitive or self-report measures. There were no differences in the proportion of patients who (a) met criteria for ICD-10 postconcussional disorder or (b) had multiple low scores on the neurocognitive measures. Conclusion. Patients with complicated MTBIs took considerably longer to return to work. They did not perform more poorly on neurocognitive measures or report more symptoms, at 3-4 weeks after injury compared to patients with uncomplicated MTBIs.

Disease-associated inflammatory biomarker profiles in blood in different subtypes of multiple sclerosis: prospective clinical and MRI follow-up study.

To identify biomarkers of disease activity and progression in multiple sclerosis (MS), we analyzed the serum profiles of cytokines, chemokines and apoptotic molecules in different subtypes of MS including clinically isolated syndrome (CIS) and correlated their levels with clinical and volumetric MRI findings obtained over a one-year follow up. Upregulated levels of apoptotic sFas molecule were found in MS patients with a worsening EDSS score and an accumulation of hypointense lesions in MRI. In such patients, the levels of MIF appeared to be higher than in non-progressing patients. In addition, increased levels of serum TNF-α and CCL2 were found especially in primary progressive MS (PPMS). These observations suggest that serum Fas and MIF are candidate biomarkers of neurological worsening related to progressive neurodegeneration, while serum TNF-α and CCL2 reflect the presence of inflammatory responses in PPMS.