Diffusion-weighted imaging in chronic Behçet patients with and without neurological findings

Diffusion tensor imaging in Behcet's disease with and without neurological involvement patients: evaluation of microstructural white matter abnormality with a tract-based spatial statistical analysis

OBJECTIVE

This study aims to assess the microstructural abnormalities in white matter (WM) among Behcet's disease (BD) patients, both with and without neurological involvement, utilising tract-based spatial statistics (TBSS) to elucidate the underlying causes of WM microstructural changes.

METHODS

This prospective study comprised 43 BD patients without neurological involvement, 15 neuro-Behcet's disease (NBD) patients with normal conventional MRI, and 54 healthy controls matched for age and sex. TBSS was applied in this diffusion tensor imaging study to conduct a whole-brain voxel-wise analysis of fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) of WM.

RESULTS

Compared to the control group, BD patients exhibited decreased FA and increased MD and RD in nearly all WM tracts, along with increased AD in the left corticospinal tract (CST), left inferior longitudinal fasciculus (ILF), and left superior longitudinal fasciculus (SLF). NBD patients also showed a widespread decrease in FA and increased MD and RD, similar to BD patients without neurological involvement. Additionally, NBD patients had increased AD in the left CST, left ILF, left SLF, left inferior fronto-occipital fasciculus (IFOF), and right CST. Compared to BD patients without neurological involvement, NBD patients exhibited a greater reduction in FA and an increase in MD and RD in WM tracts, with no significant differences in AD.

CONCLUSION

These results suggest that the main mechanism of microstructural changes in the WM of BD patients may be related to impaired fibre integrity, demyelination, and decreased myelin sheath integrity.

ADVANCES IN KNOWLEDGE

This study demonstrated BD patients without neurological involvement and NBD patients a decrease in FA and an increase in MD and RD were observed in larger areas of major WM tracts, while an increase in AD values was observed in fewer tracts. Our findings may be useful in understanding the pathophysiology underlying subclinical parenchymal involvement and neurological dysfunction in BD patients and the management of BD patients.

Pancreas and kidney changes in type 2 diabetes patients: the role of diffusion-weighted imaging

Background/aim

The aim of this study was to compare renal and pancreatic apparent diffusion-coefficient (ADC) values of diabetic patients and control subjects and to examine their potential association with several diabetes-related clinical parameters.

Materials and methods

A total of 80 sex- and age-matched patients were included in the study. Of them, 40 were patients with type 2 diabetes and 40 were nondiabetic participants. Abdominal diffusion-weighted MRIs of both groups were retrospectively reviewed. Diabetes-related clinical parameters were recorded.

Results

The difference between the mean ADC values of the patient group and the control group was significant (p = 0.012). It was also found that the mean pancreatic ADC values of diabetic patients and the control group significantly differed (p = 0.02). Besides, there were positive correlations between the mean pancreatic ADC values and age, Hb1Ac level, treatment type, and disease duration (p < 0.05). While eGFR values positively correlated with the mean renal ADC values (p < 0.05), there were negative correlations between such values and age, serum creatinine level, and disease duration (p < 0.05).

Conclusion

Renal and pancreatic ADC values of diabetic patients could potentially play a role, as markers of renal and pancreatic functions, in clinical decisions in the follow-up of such patients.

Relationship of diffusion tensor imaging parameters with neurocognitive dysfunction in patients with Behcet's disease

Behcet's disease (BD) is a chronic, multisystemic, relapsing-remitting, progressive inflammatory disorder with unknown etiology. The aim of the study is to investigate the white matter integrity and subclinical brain parenchymal involvement in Behcet's subjects by utilizing diffusion tensor imaging (DTI) and to correlate apparent diffusion coefficient (ADC), fractional anisotropy (FA), mean diffusivity (MD), and radial diffusivity (RD) values measured from the diverse distinct anatomic locations with the disease duration time and neurocognitive function test results. Thirty-five adults with Behcet's disease and 21 age-matched healthy controls were enrolled in this study. Neurocognitive functions of the patients were evaluated with the Brief Repetable Battery-Neuropsychological tests (BRB-N). In both groups, DTI metrics were calculated from 19 different locations in the brain. The association between the DTI parameters and disease duration time and neurocognitive function test results were investigated. In Behcet's disease, at the cingulum and the splenium of the corpus callosum (SCC), FA values were significantly lower compared with the controls (p = 0.0015, p = 0.003, respectively). The ADC values of the corona radiata and RD values of superior longitudinal fasciculus and SCC were significantly higher than the controls (p = 0.023, p = 0.028, p = 0.006, respectively). Significant negative correlations were found between the FA values of cingulum, genu of corpus callosum (GCC), posterior limb of internal capsule (PLIC) and disease duration time (r = - 0.368; p = 0.029 and r = - 0.337; p = 0.048 and r = - 0.527; p = 0.001 respectively). All BD subjects performed significantly lower test scores on the spatial recall test (SPART) (p = 0.001). In addition, negative correlation was found between the MD values of the parietooccipital white matter and the selective reminding test (SRT) results (r = - 0.353; p = 0.037). Our DTI study presented microstructural alterations in the neurocognitive-related areas and BRB-N test results even in patients without neurological symptoms which may imply insidious neurological involvement.

Neuro-Behcet's disease: An update on diagnosis, differential diagnoses, and treatment

Neuro-Behcet's disease (NBD) is defined as a combination of neurologic symptoms and/or signs in a patient with Behcet's disease (BD). Relevant syndromes include brainstem syndrome, multiple-sclerosis like presentations, movement disorders, meningoencephalitic syndrome, myelopathic syndrome, cerebral venous sinus thrombosis (CVST), and intracranial hypertension. Central nervous involvement falls into parenchymal and non-parenchymal subtypes. The parenchymal type is more prevalent and presents as brainstem, hemispheric, spinal, and meningoencephalitic manifestations. Non-parenchymal type includes CVST and arterial involvement. Perivascular infiltration of polymorphonuclear and mononuclear cells is seen in most histo-pathologic reports. In parenchymal NBD, cerebrospinal fluid (CSF) generally exhibits pleocytosis, increased protein and normal glucose. In NBD and CVST, CSF pressure is increased but content is usually normal. The typical acute NBD lesions in brain magnetic resonance imaging (MRI) are mesodiencephalic lesions. The pattern of extension from thalamus to midbrain provides a cascade sign. Brain MRI in chronic NBD usually shows brain or brainstem atrophy and/or black holes. The spinal MRI in the acute or subacute myelopathies reveals noncontiguous multifocal lesions mostly in cervical and thoracic lesions. In chronic patients, cord atrophy can also be seen. Brain MRI (particularly susceptibility-weighted images), MR venography (MRV) and computerized tomographic venography (CTV) can be used to diagnose CVST. Parenchymal NBD attacks can be treated with glucocorticoids alone or in combination with azathioprine. For patients with relapsing-remitting or progressive courses, shifting to more potent immunosuppressive drugs such as mycophenolate, methotrexate, cyclophosphamide, or targeted therapy is warranted. For NBD and CVST, immunosuppressive drugs with or without anticoagulation are suggested.

Evaluation of apparent diffusion coefficient measurements of brain injury in type 2 diabetics with retinopathy by diffusion-weighted MRI at 3.0 T

Diabetes is often associated with impairments in brain functioning. However, the injury of specific functioning areas of the brain is not clear. To address this problem, the present study was designed to investigate possible brain functioning change in specific brain areas, particularly in areas associated with vision function, in patients with proliferative and nonproliferative diabetic retinopathy (PDR and NPDR) using the diffusion-weighted imaging technology. Conventional MRI was performed in 45 diabetic patients, 30 of whom had diabetic retinopathy (DR) involvement (half PDR, and half NPDR) and 15 of whom were diabetic patients without retinopathy and with normal ophthalmologic examination. The apparent diffusion coefficient (ADC) values were calculated in the orbitofrontal cortex (OFC), cingulated gyrus, thalamus, dorsomedial and dorsolateral frontal cortex, and corona radiate. The ADC values of the OFC, cingulated gyrus, and visual cortex were significantly increased in patients with PDR and NPDR compared with both patients without retinopathy and the control group (P<0.01). The ADC values of the OFC, cingulated gyrus, and visual cortex were significantly increased in patients with PDR compared with NPDR. The duration of disease and values of hemoglobin A1c were significantly correlated with ADC values of the OFC, cingulated gyrus, and visual cortex, respectively (P<0.01 or <0.05). We observed significantly increased ADC values of the visual center (OFC, cingulated gyrus, and visual cortex), supporting the association between DR and impairment in brain functioning. Diffusion-weighted imaging may serve to assess subclinical neurological involvement in DR, even when brain structural changes are absent.

Imaging manifestations of Behcet's disease: Key considerations and major features

Behcet's disease is an autoimmune disease most commonly seen in the Middle East. Although primarily known with painful oral and genital ulcers, it can lead to vasculitis. Therefore, several associated complications such as thrombotic syndromes, aneurysmal arterial disease may arise. In many cases, it might be difficult to make the diagnosis purely based on clinical grounds; however, imaging plays an important role for both diagnosis and assessment of the disease's complications. We provide a comprehensive review of the most notable imaging findings of Behcet's disease.

Assessment of neural alterations in obstructive sleep apnoea syndrome: can apparent diffusion coefficient measurements be useful?

BACKGROUND AND AIMS

Our aim was to investigate whether neurological alteration in patients with obstructive sleep apnoea syndrome (OSAS) with apparently normal cerebral and cerebellar structures can be assessed by means of apparent diffusion coefficient (ADC) measurement and to investigate the association between OSAS severity and ADC values.

METHODS

Following the acquisition of diffusion-weighted cranial magnetic resonance imaging, ADC measurements were performed in 24 different apparently normal cerebral and cerebellar structures, including the bilateral frontal and parietal cortices, insulae, cingulate gyri, hippocampi, frontal and parieto-occipital periventricular white matter (PWM), caudate nuclei, putamen, thalami, cerebellar hemispheres, pons and mesencephalon in 47 OSAS patients and 20 control subjects. The ADC values of the patients and the control group were compared. The association between the apnoea-hypopnoea index (AHI) and the ADC values of the patients were investigated.

RESULTS

The ADC values in the bilateral frontal PWM were lower in the patient group than those in the control subjects (P < 0.05). The measurements in the right cingulate gyri of the OSAS patients exhibited significantly higher ADC values than those of the control group (P = 0.002). Bilateral thalamic ADC values in severe OSAS patients were significantly higher than those in mild and moderate OSAS patients (P < 0.05).

CONCLUSION

The ADC measurement is a simple and effective technique to evaluate neural alteration of the brain in patients with OSAS. ADC measurements can also be useful in the evaluation of the association between the AHI and the degree of neural alteration in the central nervous system.

Evaluation of vertebral artery involvement by Doppler sonography in patients with Behçet disease

OBJECTIVES

Neurologic lesions in Behçet disease are most frequently observed in areas supplied by the vertebrobasilar system. We aimed to evaluate possible vertebral artery involvement by Doppler sonography in patients with Behçet disease.

METHODS

Forty-five patients with Behçet disease and 29 healthy volunteers had Doppler sonography of the vertebral arteries. Patients were grouped according to neurologic examination and magnetic resonance imaging findings as follows: group 1, Behçet disease without neurologic involvement; group 2, neuro-Behçet disease; and group 3, control. Results were assessed with a 95% confidence interval.

RESULTS

The main findings of our study were as follows: (1) total vertebral artery volume flow was significantly lower in the patient groups than the control group (P< .05); (2) total volume flow was lower in group 2 than group 1, although the difference was not statistically significant; (3) peak systolic and end-diastolic velocity values were significantly lower in the patient groups than the control group; (4) right and left mean volume values were lower in group 2; and (5) resistive and pulsatility index values for the left vertebral artery were significantly higher in group 2, but no statistically significant differences were found in the resistive and pulsatility index values for the right vertebral artery.

CONCLUSIONS

Doppler sonography of the vertebral arteries in Behçet disease shows alterations that may aid in the diagnosis and treatment of this condition.

Quantitative analysis of brainstem atrophy on magnetic resonance imaging in chronic progressive neuro-Behçet's disease

OBJECTIVES

To examine whether quantitative analysis of the brainstem areas on magnetic resonance imaging (MRI) scans is useful for diagnosis as well as evaluation of disease activity in chronic progressive neuro-Behçet's disease (CPNB).

METHODS

MRI scans in patients with acute neuro-Behçet's disease (ANB) (n = 10), CPNB (n = 10), Behçet's disease with neurological manifestations non-attributable to NB (non-NB) (n = 8), and control patients with non-inflammatory neurological diseases (NID) (n = 10) were studied. The areas of midbrain tegmentum and pons were measured on mid-sagittal sections of T1-weighted images of MRI using software NIH Image J ver.1.45.

RESULTS

The areas of midbrain tegmentum as well as those of pons were significantly decreased in CPNB compared with those in the other three groups. On receiver operating characteristic (ROC) analysis, the sensitivity and specificity of the areas of brainstem combining midbrain tegmentum and pons for diagnosis of CPNB against non-CPNB (ANB+non-NB) were 80.0% and 94.4%, respectively, at cut-off value of 614.9 mm(2). Brainstem atrophy progressed most markedly during the first 2 years during the course of CPNB. Moreover, the progression rate of atrophy was closely correlated with the elevation of cerebrospinal fluid interleukin-6.

CONCLUSION

These results indicate that quantitative analysis of the brainstem areas on MRI scans is effective for diagnosis as well as for evaluation of the disease activity in CPNB. Moreover, it is suggested that an appropriate therapeutic intervention to reduce CSF IL-6 would be required as early as possible upon diagnosis of CPNB.

Brain perfusion MRI findings in patients with Behcet's disease

Objective. To search brain perfusion MRI (pMRI) changes in Behcet's disease (BD) with or without neurological involvement. Materials and Method. The pMRI were performed in 34 patients with BD and 16 healthy controls. Based on neurologic examination and post-contrast MRI, 12 patients were classified as Neuro-Behcet (group 1, NBD) and 22 patients as BD without neurological involvement (group 2). Mean transit time (MTT), time to peak (TTP), relative cerebral blood volume (rCBV), and relative cerebral blood flow (rCBF) were obtained and compared to those of healthy control group (group 3). Results. There was a significant difference in the MTT and rCBF within the pons and parietal cortex in groups 1 and 2. rCBV increased in cerebral pedicle in group 1 compared with groups 2 and 3. In the temporal lobe white matter, prolonged MTT and decreased rCBF were found in groups 1 and 2. In the corpus striatum, internal capsule, and periventricular white matter, rCBF increased in group 1 compared with group 3 and decreased in groups 1 and 2. Conclusion. Brain pMRI is a very sensitive method to detect brain involvement in patients with BD and aids the clinical diagnosis of NBD, especially in patients with negative MRI findings.