Brain perfusion MRI findings in patients with Behcet's disease

Brain white matter microstructural alterations in Behcet's syndrome correlate with cognitive impairment and disease severity: A diffusion tensor imaging study

OBJECTIVES

To evaluate the microstructural integrity of brain white matter tracts in patients with Neuro-Behcet's syndrome (NBS) and Behcet's syndrome (BS) without neurological manifestations using diffusion tensor imaging (DTI) and to investigate potential utility of DTI as a surrogate biomarker of neurocognitive functioning and disease severity.

METHODS

This cross-sectional study comprised 34 NBS patients and 32 BS patients without neurological involvement, identified based on the International Study Group of the Behcet's disease (ISGBD) and the International Consensus Recommendation (ICR) criteria, as well as 33 healthy controls. Cognitive functions, including attention, memory, language, abstraction, executive control, visuospatial skills, and sensorimotor performance were assessed using standardized questionnaires. DTI data were analyzed using tract-based spatial statistics (TBSS) and automated probabilistic tractography to investigate inter-group differences. Subsequently, correlations between tensor-derived parameters of white matter tracts, neurocognitive test scores, and disease severity measures were examined.

RESULTS

DTI revealed decreased fractional anisotropy and increased radial diffusivity, mean diffusivity, and axial diffusivity in both supratentorial and infratentorial white matter in NBS patients, indicating widespread loss of microstructural integrity. Moreover, this loss of integrity was also observed in BS patients without neurological manifestations, albeit to a lesser extent. In NBS patients, certain white matter tracts, including cingulum bundle, were associated with poor cognitive performance across multiple domains and disease severity.

DISCUSSION

DTI findings might potentially serve as a neuroimaging marker to predict the extent of neurocognitive impairment and disease severity associated with central nervous system involvement in BS.

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.

Autoimmune diseases of the brain, imaging and clinical review

There is an extensive spectrum of autoimmune entities that can involve the central nervous system, which has expanded with the emergence of new imaging modalities and several clinicopathologic entities. Clinical presentation is usually non-specific, and imaging has a critical role in the workup of these diseases. Immune-mediated diseases of the brain are not common in daily practice for radiologists and, except for a few of them such as multiple sclerosis, there is a vague understanding about differentiating them from each other based on the radiological findings. In this review, we aim to provide a practical diagnostic approach based on the unique radiological findings for each disease. We hope our diagnostic approach will help radiologists expand their basic understanding of the discussed disease entities and narrow the differential diagnosis in specific clinical scenarios. An understanding of unique imaging features of these disorders, along with laboratory evaluation, may enable clinicians to decrease the need for tissue biopsy.

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.

Acquired neurocutaneous disorders

A variety of neurologic diseases have cutaneous manifestations. These may precede, coincide with, or follow the neurologic findings. An array of autoimmune, genetic, and environmental factors play a role in expression and severity of the neurologic burden in these conditions. This chapter emphasizes congenital and genetic disorders, but we also discuss the pathophysiology and manifestation of various acquired neurocutaneous disorders with an emphasis Behcet's disease, dermatomyositis, Sjögren's syndrome, systemic lupus erythematosus, scleroderma, Parry-Romberg syndrome and Degos disease.

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.

Neuro-Behçet syndrome

Behçet syndrome (BS) is an idiopathic chronic relapsing multisystem vascular-inflammatory disease of unknown origin. As the disease affects many organs and systems and shows a wide range of clinical manifestations and presentations, it is prefereable to call Behçet's a syndrome (BS) rather than a disease. Nervous system involvement, known as "neuro-BS" (NBS), is seen in about 5-10% of all cases. Clinical and imaging evidence suggests that primary neurologic involvement in BS may be subclassified into two major forms: the first, which is seen in the majority of patients, may be characterized as a vascular-inflammatory central nervous system disease with focal or multifocal parenchymal involvement, mostly presenting with a subacute brainstem syndrome and hemiparesis (intra-axial NBS); the other, which has few symptoms and a better neurologic prognosis, may be caused by isolated cerebral venous sinus thrombosis and intracranial hypertension (extra-axial NBS), occurring in 10-20% of the cases. These two types are rarely seen in the same individual, and their pathogenesis is likely to be different. Isolated behavioral syndromes and peripheral nervous system involvement are rare, whereas a vascular type headache is relatively common and independent from neurologic involvement. Neurologic complications secondary to systemic involvement of BS, as well as neurologic complications related to BS treatments are considered as secondary neurologic involvement of the syndrome. The core histopathologic phenomenon seems to be a vasculitic involvement in some cases, and low-grade chronic nonspecific inflammation in others. As the neurologic involvement in this syndrome is so heterogeneous, it is difficult to predict its course and prognosis, and its response to treatment. Currently, treatment options for NBS are limited to attack therapies with high-dose intravenous methylprednisolone followed by a prolonged oral taper, symptomatic management, and generally the use of azathioprine, cyclophosphamide, interferon-α and anti-TNF agents for long-term preventive treatment, although there no evidence for their efficacy.

Recurrent headaches: a case of neurological Behçet's disease

A 48-year-old black male, of Nigerian heritage, presented with a 24-hour history of frontal headache of gradual onset. The headache characteristic was migranous, being described as throbbing in nature and located to the right frontal area with associated blurring of vision. Although similar to prior frequent headaches, there was now increasing unsteadiness on walking. Diagnosed 10 years earlier with Behçet's disease, the initial presentation was with oral and genital ulceration. Recurrent episodes of headache caused by neurological flare-ups resulted in a stroke at the age of 46 years. This previous stroke was ischaemic in character with involvement of the brainstem, pons, midbrain and right cerebral peduncle with extension into the right internal capsule. Surveillance brain imaging (computed tomographic and magnetic resonance imaging with venography) 10 months earlier showed brainstem disease activity (Figure 1a) with disease quiescence a month later (Figure 1b) following an escalation of immunosuppressant therapy. Regular medications comprised prednisolone 10 mg (however, regular recurrences had resulted in him taking doses of between 20 and 30 mg/day of prednisolone for most of the past 24 months) and azathioprine 150 mg daily, aspirin 75 mg daily, one adcal D3 twice daily with weekly alendronic acid, and omeprazole 20 mg daily. For headache he took topiramate 25 mg daily and for depression mirtazepine 15 mg daily. The patient was also addicted to a high level of cannabis use which he was reluctant to stop as he felt it helped his symptoms. On examination he was apyrexial and cardiovascularly stable. Neurological examination revealed a residual horizontal nystagmus to the right on lateral gaze, mild left hemiparesis with moderate spasticity, in addition to dysarthria and dysphonia from his prior stroke. A new feature was an exacerbation of gait unsteadiness. Blood tests were unremarkable and specifically the erythrocyte sedimentation rate was normal at 2 mm/hr (normal range 0-10 mm/hr). Immediate therapy involved an increase in steroid dosage to methyl prednisolone 1 g/day for 3 days, followed by oral prednisolone 60 mg daily. This was maintained for 2 weeks and then reduced by 10 mg/week to a maintenance dose of 10 mg/day. Magnetic resonance scanning revealed a marked increase in inflammation of the brainstem (Figure 1c). The patient required physiotherapy and occupational therapy with psychiatric input and was able to leave the hospital after 29 days.

Behcet’s disease: a hardly diagnosed orphan disorder

Behcet’s disease is a multisystem autoimmune disease with variable clinial manifestations. The diagnosis may pose a difficult challenge for the clinician, who has to be familiar with the wide spectrum and combination of the symptoms of Behcet’s disease. It is considered a rare disease in Hungary, and there are only few reports on Behcet’s disease in the Hungarian literature. However, the past history of Hungary, the worldwide growing incidence of the disease, and the authors’ experience raise the possibility that the occurrence of the disease is higher than previously thought. In this review the authors present and discuss literature data on the pathogenesis and pathomechanism, as well as their own experience concerning the symptomatology of Behcet’s disease in order to promote diagnosis and offer adequate therapy for the patients. The authors presume that the importance of the disease is underestimated in Hungary due to a considerable number of unrecognized cases and they propose to establish a national registry for Behcets disease. Orv. Hetil., 2013, 154, 93–101.

Neuro-Behçet, pseudotumor cerebri and ocular signs: a rare association

Introduction: The central nervous system involvement in Behçet’s disease occurs in 5–30% of cases. The diagnosis of pseudotumor cerebri is even rarer (only 22 cases reported worldwide).

Purpose: To emphasize the importance of differential diagnosis in a case of pseudotumor cerebri in the context of ocular inflammation. Methods: V.A.V.R., a 31 year old female, was diagnosed with pan-uveitis on the left eye associated with recurrent bipolar aphthosis. During the etiological investigation, there was an onset of a left hemiparesis and facial palsy.

Results: The central nervous system (CNS) neuroradiological investigation revealed a space-occupying lesion within the right hemisphere with intense signal enhancement with gadolinium. It globally reached the nucleo-basal structures and induced deviation of the middle structures (including homolateral ventricle). Cytochemical analysis of cerebrospinal fluid (CSF) was negative for atypical cells. The ophthalmological features regressed with the corticosteroid and immunosuppressive therapy instituted. The final diagnosis was of pseudotumor cerebri in the context of Behçet’s disease.

Conclusion: In Behçet’s disease, a cerebral space-occupying lesion should lead to a diagnosis of pseudotumor cerebri. The correct diagnosis will determine an appropriate therapy and may prevent an inappropriate neurosurgical approach. The cortico and immunotherapy allowed a substantial regression of the lesion.