Spinal adhesive arachnoiditis in an adult patient with spinal muscular atrophy type 3 treated with intrathecal therapy.

BACKGROUND: Spinal adhesive arachnoiditis is a chronic inflammatory process of the leptomeninges and intrathecal neural elements. The possible causes of arachnoiditis are: infections, injuries of spinal cord, surgical procedures and intrathecal administration of therapeutic substances or contrast. CASE PRESENTATION: We present a case of 56-old woman with spinal muscular atrophy type 3 who developed a severe back pain in the lumbosacral region after the fifth dose of nusinersen given intrathecally. Magnetic resonance of lumbosacral spine showed spinal adhesive arachnoiditis. She received high doses of methylprednisolone intravenously, and later non-steroidal anti-inflammatory drugs, alpha lipoic acid, vitamins and rehabilitation with slight improvement. CONCLUSIONS: The authors summarize that scheduled resonance imaging of the lumbosacral spine may be an important element of the algorithm in the monitoring of novel, intrathecal therapy in patients with spinal muscular atrophy.

Comparison of dynamic susceptibility contrast enhanced MR and FDG-PET brain studies in patients with Alzheimer's disease and amnestic mild cognitive impairment.

BACKGROUND: The aim of this study was to compare Dynamic Susceptibility Contrast Enhanced MRI (DSC-MRI) and PET with [18F]flurodeoxyglucose (FDG-PET) in the diagnosis of Alzheimer's Disease (AD) and amnestic Mild Cognitive Impairment (aMCI). METHODS: Twenty-seven age-and sex-matched patients with AD, 39 with aMCI and 16 controls underwent brain DSC-MRI followed by FDG-PET. Values of relative Cerebral Blood Volume (rCBV) and rCBV z-scores from frontal, temporal, parietal and PCG cortices were correlated with the rate of glucose metabolism from PET. Sensitivity, specificity and accuracy of DSC-MRI and FDG-PET in the diagnosis of AD and aMCI were assessed and compared. RESULTS: In AD, hypoperfusion was found within all the examined locations, while in aMCI in both parietal and temporal cortices and left PCG. FDG-PET showed the greatest hypometabolism in parietal, temporal and left PCG regions in both AD and aMCI. FDG-PET was more accurate in distinguishing aMCI from the controls than DSC-MRI. In the AD and combined group (AD + aMCI) there were numerous correlations between DSC-MRI and FDG-PET results. CONCLUSIONS: In AD the patterns of hypoperfusion and glucose hypometabolism are similar, thus DSC-MRI may be a competitive method to FDG-PET. FDG-PET is a more accurate method in the diagnosis of aMCI.

Ischemic stroke as a rare complication of wasp venom allergy: two clinical scenarios.

Neurological complications after a single Hymenoptera insect sting are very rare. The authors of this paper describe two instances of cerebral ischemic stroke that occurred immediately after a wasp sting. Two distinct pathomechanisms involved in the cases are put forward. When diagnosing such cases, it is vital to rule out the possibility of an immunoglobulin E (IgE)-dependent reaction of hypersensitivity. However, if sIgE antibodies against wasp venom extract and/or its allergenic components are detected, after hospitalization the patient should be qualified for venom immunotherapy, which is the only efficient method of protection from severe allergic reactions caused by an insect sting. Although the incidence of ischemic stroke in patients stung by insects is very low, it is important to be aware of this complication. This will allow rapid implementation of appropriate diagnostics and treatment. The optimal stroke treatment (thrombolysis or mechanical thrombectomy) in these rare cases has not yet been established.

The value of different diffusion-weighted magnetic resonance techniques in the diagnosis of middle ear cholesteatoma. Is there still an indication for echo-planar diffusion-weighted imaging?

PURPOSE: The aim of the study was to analyse the value of 2 different diffusion-weighted imaging (DWI) techniques (echo-planar imaging [EPI] and on-echo-planar imaging [non-EPI]) in the diagnosis of cholesteatoma. MATERIAL AND METHODS: Our material consisted of 32 subjects suspected of cholesteatoma, who underwent magnetic resonance imaging of the temporal bone using both EPI and non-EPI DWI. Two independent readers retrospectively analysed magnetic resonance images. Intra- and interobserver agreements as well sensitivity, specificity, and negative (NPV) and positive (PPV) predictive values of both DWI sequences were assessed. RESULTS: Using non-EPI DWI all cholesteatomas were correctly diagnosed by both readers with no false negative nor inconclusive cases and with only one false positive result. Non-EPI DWI revealed high interobserver agreement (k = 1) and high correlation with histopathological results (r = 0.895). EPI DWI misdiagnosed 27-31% of cholesteatomas (false negative results), showing also significantly low interobserver agreement (k = 0.373) and low correlation with histopathological results (r = 0.328 for reader 1 and r = 0.267 for reader 2). Non-EPI DWI revealed very high sensitivity (100%), specificity (83.3%), NPV (100%), and PPV (96.3%) in comparison to EPI DWI, which showed lower sensitivity (69.2%), specificity (66.6-83.3%), NPV (33.3-38.4%), and PPV (90.0-94.7%). CONCLUSIONS: Non-EPI DWI with high sensitivity, specificity, and interobserver agreement is a very reliable technique in detecting middle ear cholesteatoma regardless of the pre- or postoperative state of the ear, and it should entirely replace EPI DWI in clinical practice.

Acute cerebral venous thrombosis - still an underdiagnosed pathology in emergency computed tomography of the brain.

PURPOSE: Acute cerebral venous thrombosis (CVT) is a rare condition that can lead to a serious clinical state; thus, prompt diagnosis and treatment are mandatory. Head computed tomography (CT) plays a crucial role in the initial prompt diagnosis in the emergency setting. The aim of the study was to retrospectively analyse emergency head CT studies and the rate of incorrect diagnoses and main sources of pitfalls. MATERIAL AND METHODS: Retrospective analysis of 31 emergency CT studies (22 without contrast, 19F/12M, age range: 4-94 years) of patients with confirmed acute CVT. RESULTS: Thrombosed dural sinuses were found in 24/31 (77.4%) cases, thrombosed veins in 7/31 (22.6%) cases, no lesions within vessels in 2/31 (6.5%) cases. Haemorrhagic brain lesions were found in 9/31 (29%) cases, hypodense oedema in 6/31 (19.6%) cases, brain swelling in 1/31 (3.2%) cases, and no parenchymal lesions were revealed in 15/31 (48.4%) cases. Correct diagnosis of CVT was established in 15 cases (48.4%); however, it was incorrect in 16 cases (51.6%). Incorrect cases consist of 4 groups: 1 - with both vascular and parenchymal lesions that were overlooked (50%), 2 - with vascular lesions only, which were either overlooked, misinterpreted, or covered by artefacts (31.3%,), 3 - with parenchymal lesions only, which were misinterpreted (12.5%), and 4 - with no lesions present in the emergency head CT (6.2%). CONCLUSIONS: The high rate of incorrect diagnoses of acute CVT based on emergency head CT requires constant training of radiologists and their close cooperation with clinicians because a delayed diagnosis may be lethal to the patient.

A Review of Neuroimaging in Rare Neurodegenerative Diseases.

PURPOSE: Due to the variety of clinical symptoms that occur in rare neurodegenerative diseases and difficulties in the correct diagnosis, there is a need to learn their characteristic imaging findings by using conventional MRI. That knowledge helps to determine the appropriate differential diagnosis and avoid misdiagnosis. The aim of this review is to present the typical neuroimaging signs of the selected neurodegenerative disorders and to create a practical approach to imaging findings useful in everyday clinical practice. Images: Images of progressive supranuclear palsy (PSP), multiple system atrophy (MSA), corticobasal degeneration (CBD), Creutzfeldt-Jakob disease (CJD), Wilson's disease (WD), and cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) are provided to visualize and distinguish the typical features of those diseases and therefore to assist neurologists and neuroradiologists in decision-making process. CONCLUSIONS: It is important to know the characteristic MRI features of rare neurodegenerative diseases and to use them in everyday clinical practice. MRI is a valuable tool when considering the initial diagnosis because it is proven to be very useful in the differentiation of more advanced stages of the rare neurodegenerative diseases but also from other neurodegenerative disorders.

Navigated neuroendoscopy combined with intraoperative magnetic resonance cysternography for treatment of arachnoid cysts.

Endoscopic cystocysternostomy or cystoventriculostomy is the treatment of choice in patients with symptomatic intracranial arachnoid cysts. There are no objective diagnostic tests for reliable intraoperative evaluation of the effectiveness of performed stomies. The aim of this prospective open-label study is to demonstrate for the first time the usefulness of intraoperative cysternography performed with the low-field 0.15-T magnetic resonance imager Polestar N20 during endoscopic cysternostomies. The study was performed in patients operated for middle fossa arachnoid cysts (n = 10), suprasellar cysts (n = 4), paraventricular or intraventricular cysts (n = 6), and a pineal cyst (n = 1). The operations were performed with use of a navigated neuroendoscope. Intraoperative magnetic resonance (iMR) cysternography was performed before and after the cystostomy. In each case, iMR cysternography was safe and could show clearly the cyst morphology and the effectiveness of performed endoscopic cystostomies. In six cases, iMR cysternography had a significant influence of the surgical decision (p = 0.027). The rate of inconsistency between the intraoperative observations and iMR imaging-based findings was 29%. A good contrast flow through the fenestrated cyst walls correlated with a good long-term clinical outcome (ρ = 0.54, p < 0.05) and good long-term radiological outcome (ρ = 0.72, p < 0.05). Intraoperative low-field MR cysternography is a safe and reliable method for assessment of the efficacy of performed endoscopic cystostomies and has significant influence on the surgical decision. It may be reliably used for prediction of the long-term clinical and radiological outcome.

Interferon-free therapy as the cause of white matter tracts and cerebral perfusion recovery in patients with chronic hepatitis C.

The purpose of this study was to assess cerebral microstructural and perfusion changes in patients with chronic hepatitis C virus (HCV) infection before and after interferon-free therapy, using advanced magnetic resonance (MR) techniques. Eleven HCV-positive patients underwent diffusion tensor imaging (DTI) and perfusion-weighted imaging (PWI) using a 1.5T MR unit, before and 24 weeks after completion of interferon-free therapy. DTI fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values were obtained from 14 white matter tracts. PWI values of relative cerebral blood volume (rCBV) and relative cerebral blood flow (rCBF) were assessed from 8 areas, including basal ganglia, and cortical and white matter locations. In HCV-positive patients therapy with ombitasvir, paritaprevir boosted with ritonavir and dasabuvir, with or without ribavirin, was scheduled. Cognitive tests were used to assess cognitive function. We found increased FA values after interferon-free therapy compared to values obtained before treatment in HCV patients in almost all white matter tracts. We also observed elevated rCBV values in basal ganglia after therapy. There were significant correlations between improvement in the score of cognitive tests and increased FA values in both inferior fronto-occipital fascicles and left posterior cingulum after treatment. Liver fibrosis regression in elastography, APRI and improvement in cognitive tests were observed. This is the first report of interferon-free therapy as the cause of white matter tracts recovery as well as cerebral perfusion improvement in HCV-infected patients, indicating better functioning of frontal lobes after interferon-free treatment.

The metabolic alterations within the normal appearing brain in patients with Hashimoto's thyroiditis are correlated with hormonal changes.

Hashimoto's thyroiditis (HT) is the most common autoimmune disease in humans usually associated with subsequent hypothyroidism. The purpose of the study was to assess metabolic alterations within the normal appearing brain in subjects with HT using MR spectroscopy (MRS) and to correlate MRS measurements with hormonal concentrations. Fifty-five HT patients (mean age 43.5 yrs) and 30 healthy controls (mean age 42.5 yrs) were examined with the use of a 1.5 T MR scanner. There were no signs of central nervous system involvement in the studied group. The MRS examinations were performed using the single voxel method. The voxels were placed in the left parietal white matter (PWM) and the posterior cingulate gyrus (PCG). The NAA/Cr, Cho/Cr, and mI/Cr ratios were calculated. The correlations between metabolite ratios and hormonal concentrations (TSH, fT3, fT4) as well as anti-TG and anti-TPO levels were also assessed. We found significantly (p < 0.05) decreased NAA/Cr ratios in PCG and PWM in HT subjects compared to the control group. There were no other significant differences in metabolite ratios. We observed significant positive correlations between the NAA/Cr ratio in PCG as well as the PWM and fT3 level. There was also a significant negative correlation between the Cho/Cr ratio in the PCG and fT4 level. MRS could be a sensitive biomarker capable of depicting early cerebral metabolic disturbances associated with HT. Our findings may indicate the reduction of neuronal activity within the normal appearing brain in patients with HT as well as suggesting that there is a possible biological association between thyroid dysfunction and cerebral metabolic changes.

Imaging of cerebrospinal fluid flow: fundamentals, techniques, and clinical applications of phase-contrast magnetic resonance imaging.

Cerebrospinal fluid (CSF) is a dynamic compartment of the brain, constantly circulating through the ventricles and subarachnoid space. In recent years knowledge about CSF has expended due to numerous applications of phase-contrast magnetic resonance imaging (PC-MRI) in CSF flow evaluation, leading to the revision of former theories and new concepts about pathophysiology of CSF disorders, which are caused either by alterations in CSF production, absorption, or its hydrodynamics. Although alternative non-invasive techniques have emerged in recent years, PC-MRI is still a fundamental sequence that provides both qualitative and quantitative CSF assessment. PC-MRI is widely used to evaluate CSF hydrodynamics in normal pressure hydrocephalus (NPH), Chiari type I malformations (CMI), syringomyelia, and after neurosurgical procedures. In NPH precisely performed PC-MRI provides reliable clinical information useful for differential diagnosis and selection of patients benefiting from surgical operation. Patients with CMI show abnormalities in CSF dynamics within the subarachnoid space, which are pronounced even further if syringomyelia coexists. Another indication for PC-MRI may be assessment of post-surgical CSF flow normalisation. The aim of this review is to highlight the significance of CSF as a multifunctional entity, to outline both the physical and technical background of PC-MRI, and to state current applications of this technique, not only in the diagnosis of central nervous system disorders, but also in the further clinical monitoring and prognosis after treatment.

A pictorial essay of the most atypical variants of the vermiform appendix position in computed tomography with their possible clinical implications.

PURPOSE: The tip of the appendix may be located in various areas of the abdominal cavity due to its variable length and/or the changeable position of the caecum. Although in the case of an atypical position the tip is usually located behind the caecum, there are possible locations that occur very rarely. Therefore, in the case of appendicitis the symptoms may lead to the wrong diagnosis. The aim of this study is to present the most atypical locations of the tip of the appendix found on CT (computed tomography) scans and thus help to avoid misdiagnoses. IMAGING FINDINGS: The most unusual locations of the tip of the appendix found in healthy subjects included: left inferior quadrant, along the lower edge of the liver near the gallbladder and the right kidney, the tip touching the duodenum, the rectum or appendages, and a long appendix located in the scrotum as the content of a hernia. In these positions, appendicitis may mimic acute diverticulitis, cholecystitis, duodenal ulcer, duodenitis, enteritis, or adnexal or testis pathologies. CONCLUSIONS: It is important to be aware of atypical locations of the appendix because appendicitis in an unusual area may mimic other acute abdominal diseases and delay the proper treatment.

Bilateral thalamic stroke after tonsillectomy in a patient with collateral extracranial anastomosis - case report.

Haemorrhage remains the most frequent and serious complication of tonsillectomy. When bleeding is recurrent, gushing, and ceases spontaneously, pseudoaneurysm of the injured artery in the proximity of the tonsillar bed should be suspected. Haemorrhage related to pseudoaneurysm occurs most commonly in the first 30 days after surgery. It can sometimes be excessive and requires a revision procedure such as external carotid artery (ECA) ligation or embolisation. During those procedures, ECA should be checked for possible anastomoses, otherwise the bleeding may persist despite the intervention. We report an unusual case of a patient with recurrent post-tonsillectomy haemorrhage due to pseudoaneurysm of the facial artery, which persisted after ECA ligation because of the presence of collateral occipital-vertebral anastomosis. Due to the recurrence of bleeding episodes, endovascular treatment was implemented. However, the embolisation was complicated by bilateral thalamic stroke with unclear mechanism. This case highlights the importance of anastomosis between ECA and the vertebrobasilar system, both in recurrence of significant post-tonsillectomy bleeding and in potential thromboembolic complications. Therefore, ECA ligation should always be accompanied by exclusion of possible anastomoses. In cases of non-life-threatening bleeding, embolisation seems to be the proper and more selective therapy.

Quantitative magnetic resonance assessment of brain atrophy related to selected aspects of disability in patients with multiple sclerosis: preliminary results.

PURPOSE: The aim of this volumetric study was to evaluate the relationship between brain atrophy quantification in multiple sclerosis (MS) patients and the progression of disability measured by neurological standardised tests. MATERIAL AND METHODS: Seventeen patients (mean age 40.89 years) with clinically definite MS and 24 control subjects (mean age 38.45 years) were enrolled in the study. Brain examinations were performed on a 1.5T MR scanner. Automatic brain segmentation was done using FreeSurfer. Neurological disability was assessed in all patients in baseline and after a median follow-up of two years, using EDSS score evaluation. RESULTS: In MS patients we found significantly (p < 0.05) higher atrophy rates in many brain areas compared with the control group. The white matter did not show any significant rate of volume loss in MS patients compared to healthy controls. Significant changes were found only in grey matter volume in MS subjects. At the follow-up evaluation after two years MS patients with deterioration in disability revealed significantly decreased cerebral volume in 14 grey matter areas at baseline magnetic resonance imaging (MRI) compared to MS subjects without disability progression. CONCLUSIONS: Grey matter atrophy is associated with the degree of disability in MS patients. Our results suggest that morphometric measurements of brain volume could be a promising non-invasive biomarker in assessing the volumetric changes in MS patients as related to disability progression in the course of the disease.

Diagnostic Difficulties in Primary Pauci-Melanotic Leptomeningeal Melanomatosis.

We present a rare case of primary malignant melanoma of the central nervous system. We underline the difficulties we faced during diagnostic procedures. Finally, postmortem examination revealed the diagnosis of primary pauci--melanotic leptomeningeal melanomatosis.

The role of diffusion and perfusion magnetic resonance imaging in differentiation of haemangioblastomas and pilocytic astrocytomas.

PURPOSE: Haemangioblastomas (HABLs) and pilocytic astrocytomas (PAs) are brain tumours presenting similar appearance and location in conventional magnetic resonance (MR) imaging. The purpose of our study was to determine whether a detailed analysis of diffusion (DWI) and perfusion (PWI) characteristics can be useful in preoperative differentiation of these tumours. MATERIAL AND METHODS: The study group consisted of biopsy proven six HABLs and six PAs, which underwent preoperative standard MR examinations including PWI and DWI. In PWI relative cerebral blood volume (rCBV) and the shape of perfusion curves (parameters of peak height - rPH and percentage of signal recovery - rPSR) were analysed. All perfusion parameters were measured for the entire tumour core (mean rCBV, mean rPH, mean rPSR) and in regions with maximal values (max rCBV, max rPH, max rPSR). In DWI parameters of apparent diffusion coefficient (ADC) from the entire tumour core (mean ADC) and in regions with minimal values (min ADC) were evaluated. RESULTS: Compared to PAs, HABLs presented significantly higher rCBV and rPH values and lower mean rPSR value. PAs showed significantly lower rCBV and rPH values and higher mean rPSR value. Mean rCBV showed no overlap in the values between HABLs and PAs, and thus it provided the highest accuracy in differentiating between them. Max rPSR, mean ADC, and min ADC did not show any significant differences. CONCLUSIONS: High rCBV values and deep perfusion curves with only partial return to the baseline are characteristic features of HABLs differentiating them from PAs, which show lower rCBV values and perfusion curves overshooting the baseline. Diffusion parameters are not useful in differentiation of these tumours.

Metastatic pulmonary calcification as a rare complication of end-stage renal disease with coexistence of pulmonary metastases from renal cell carcinoma: case report and literature review.

PURPOSE: We present a case of metastatic pulmonary calcification (MCP) in an asymptomatic patient with chronic kidney disease after renal transplantation and nephrectomy due to renal cancer. Chest computed tomography (CT) revealed bilateral, diffuse, centrilobular ground-glass opacities and heterogeneous, high-density areas distributed throughout the lungs, predominantly in the upper and middle lobes. Unusually, in our patient the metastatic calcification coexisted with pulmonary metastases from renal cell carcinoma associated with end-stage renal disease. To our knowledge, such coexistence has not been previously described. CASE REPORT: CT, particularly high-resolution chest computed tomography (HRCT), plays an important role in detection and follow-up of MPC findings, which include ground-glass opacities and partially calcified nodules or consolidations, predominantly in the upper lung zones. Correct diagnosis is important because misdiagnosis may lead to improper or unnecessary treatment and/or procedures. CONCLUSIONS: MPC is a rare condition that results from calcium deposition in the normal pulmonary parenchyma. MPC commonly occurs in patients with end-stage chronic kidney disease due to abnormalities in calcium and phosphate metabolism. It is worth pointing out that despite the fact that the condition is called metastatic, it is a relatively benign lung disease with a generally good long-term prognosis.

Diagnostic Imaging and Clinical Features of Intracranial Hypotension - Review of Literature.

Intracranial hypotension (IH) is an uncommon, benign, and usually self-limiting condition caused by low cerebrospinal fluid (CSF) pressure, usually due to CSF leakage. The dominant clinical finding is an orthostatic headache. Other common clinical features include fever, nausea, vomiting, and tinnitus. Magnetic resonance imaging (MRI) plays an important role in the diagnosis and follow-up of patients with IH. Specific MRI findings include intracranial pachymeningeal enhancement, sagging of the brain, pituitary enlargement, and subdural fluid collections. Intracranial hypotension can mimic other conditions such as aseptic meningitis or pituitary adenomas. Differential diagnosis is important, because misdiagnosis may lead to unnecessary procedures and prolonged morbidity.

Cerebral Metastases of Lung Cancer Mimicking Multiple Ischaemic Lesions - A Case Report and Review of Literature.

BACKGROUND: Restricted diffusion that is found on magnetic resonance diffusion-weighted imaging (DWI) typically indicates acute ischaemic stroke. However, restricted diffusion can also occur in other diseases, like metastatic brain tumours, which we describe in this case report. CASE REPORT: A 57-year-old male, with a diagnosis of small-cell cancer of the right lung (microcellular anaplastic carcinoma), was admitted with focal neurological symptoms. Initial brain MRI revealed multiple, disseminated lesions that were hyperintense on T2-weighted images and did not enhance after contrast administration; notably, some lesions manifested restricted diffusion on DWI images. Based on these findings, disseminated ischaemic lesions were diagnosed. On follow-up MRI that was performed after 2 weeks, we observed enlargement of the lesions; there were multiple, disseminated, sharply outlined, contrast-enhancing, oval foci with persistent restriction of diffusion. We diagnosed the lesions as disseminated brain metastases due to lung cancer. To our knowledge, this is the first description of a patient with brain metastases that were characterised by restricted diffusion and no contrast enhancement. CONCLUSIONS: Multiple, disseminated brain lesions, that are characterised by restricted diffusion on DWI, typically indicate acute or hyperacute ischemic infarcts; however, they can also be due to hypercellular metastases, even if no contrast enhancement is observed. This latter possibility should be considered particularly in patients with cancer.

The possible meaning of fractional anisotropy measurement of the cervical spinal cord in correct diagnosis of amyotrophic lateral sclerosis.

Diagnosis of amyotrophic lateral sclerosis (ALS) is based on clinical criteria and electrophysiological tests (electromyography, and transcranial magnetic stimulation). In the search for ALS biomarkers, the role of imaging procedures is currently emphasized, especially modern MR techniques. MR procedures were performed on 15 ALS patients and a sex- and age-matched control group. The MR examinations were performed with a 1.5-T MR unit, and the protocol consisted of sagittal T1-weighed images, sagittal and axial T2-weighed images, and sagittal T2-weighed FAT SAT images followed by an axial diffusion tensor imaging (DTI) sequence of the cervical spinal cord. FA values in individual segments of the cervical spinal cord were decreased in the ALS group in comparison with the control group. After comparing FA values for anterior, posterior, and lateral corticospinal columns, the greatest difference was observed between the C2 and C5 segments. Spinal cord assessment with the use of FA measurements allows for confirmation of the motor pathways lesion in ALS patients. The method, together with clinical criteria, could be helpful in ALS diagnosis, assessment of clinical course, or even the effects of new drugs. The results also confirmed the theory of the generalized character of ALS.