Three - dimensional fluid attenuated inversion recovery sequence on 3 tesla magnetic resonace imaging in cranial nerve pathologies: Two case reports

Three - dimensional fluid attenuated inversion recovery sequence (3D-FLAIR) was introduced as a practical sequence which helps to reduce the cerebrospinal fluid pulsation and flow artefacts of conventional 2D acquisition and brings contiguous slices, ability in reformatting in variable planes which are typical features of 3D acquisition. 3D - FLAIR has been applied on assessing several neurologic pathologies. In this article, we introduce the application of 3D - FLAIR sequence without contrast enhancement on detecting abnormalities of cranial nerve pathology by presenting two cases, acute vestibular neuritis and facial nerve palsy. We suggest that 3D - FLAIR is the relatively useful sequence in detecting cranial nerve pathologies.

The value of double inversion recovery MRI sequence in assessment of epilepsy patients

Background The double inversion recovery (DIR) pulse sequence was introduced several years ago and since that it grew important value in clinical neuroimaging. We aimed to assess the added value of double inversion recovery in evaluation of epileptic patients. Results In mesial temporal sclerosis, the measured contrast parameters (SNR, CR, CNR and AI) were found to be significantly higher in DIR than in FLAIR and T2 sequences. In cases of focal cortical dysplasia, significantly higher CNR and AI in DIR than in T2 and FLAIR. Also DIR showed higher detection of the increased cortical thickness and cortical signal intensity than the T2 and FLAIR sequences. In tuberous sclerosis cases, the DIR showed higher visibility of the lesions than the T2 and FLAIR. Also DIR showed higher ability to detected grey-white matters junction blurring. Conclusions Our study concluded that the greatest value of the double inversion recovery sequence is its higher ability in detecting multiple characteristics of the lesions in a one sequence.

Gut-Derived Metabolite Phenylacetylglutamine and White Matter Hyperintensities in Patients With Acute Ischemic Stroke

Background: White matter hyperintensity (WMH) burden is associated with a higher risk of ischemic stroke. Phenylacetylglutamine (PAGln) is a gut microbiota-derived metabolite that may induce cardiovascular events by activating platelets and increasing the risk of thrombosis. The relationship between plasma PAGln and WMH burden in patients with ischemic stroke is unknown. This study was designed to investigate the association between plasma PAGln and WMH burden in patients with acute ischemic stroke.Methods: A total of 595 patients with acute ischemic stroke were enrolled in this study within 14 days of symptom onset. The burden of WMH was evaluated using the Fazekas scale based on the fluid-attenuated inversion recovery sequence. The severity of overall WMH was defined as none–mild WMH (total Fazekas score 0–2) or moderate–severe WMH (total Fazekas score 3–6). Based on the severity of periventricular WMH (P-WMH) and deep WMH (D-WMH), patients were categorized into either a none–mild (Fazekas score 0–1) group or a moderate–severe (Fazekas score 2–3) group. Plasma PAGln levels were quantified using liquid chromatography–mass spectrometry.Results: We found that patients with moderate–severe overall WMH showed higher plasma PAGln levels than patients with none–mild overall WMH, and similar results were found in the analyses according to P-WMH and D-WMH. The logistic regression analysis showed that the fourth PAGln quartile was independently associated with moderate–severe overall WMH (adjusted 95% CI 1.134–4.018) and P-WMH (adjusted 95% CI 1.174–4.226).Conclusion: These findings suggest that higher plasma PAGln levels are associated with moderate–severe overall WMH and P-WMH in patients with acute ischemic stroke.

Comparison of Differential Diagnosis of Lung Cancer by Diffuse Weighted Imaging and Sagittal Imaging with Short Inversion Recovery Sequence

The differential diagnosis of advanced lung cancer is difficult in clinical practice. Our study aims to compare the value of diffusion weighted imaging (DWI) with short-term inversion recovery sequence (STIR) for sagittal imaging in the differential diagnosis of lung cancer. 149 patients with non-small cell lung carcinoma (NSCLC) were enrolled and underwent DWI and STIR sagittal imaging. To quantify cancer types, we evaluated the apparent diffusion coefficient (ADC) value on DWI and the contrast ratio (CRs) on sagittal imaging. The ADC values of subclasses in NSCLC were significantly higher than small cell lung carcinoma (SCLC) (p <0.01). The mean CRs were 1.59 for SCLC and 1.30 for NSCLC with a significant difference (p < 0.01). Large cell carcinomas (LCC) and adenocarcinomas have significant differences compared to small cell carcinomas (SCC) without difference between squamous cell carcinomas (p > 0.05); this is also the case for CRs. Squamous cell carcinoma and adenocarcinoma have significant differences compared to SCC without difference in LCC (p > 0.05). Qualitative evaluation of the feasible thresholds DWI and STIR showed that the thresholds were 0.9810−3 mm2/s and 1.37 respectively. The specificity and accuracy was 78.5% is 85.3% for DWI, which was significantly higher than STIR (56.3% and 61.0%). The combination of DWI and STIR sequences was superior to DWI alone with an accuracy rate of 94.3%. DWI is more helpful than STIR in differentiating SCLC and NSCLC, and their combined use can significantly improve diagnosis accuracy.

Haemorrhagic encephalitis in the garb of scrub typhus

A 19-year-old girl presented with fever, headache, vomiting and drowsiness. She had grade 1 papilloedema and neck rigidity but no focal deficits or seizures. Cerebrospinal fluid analysis revealed lymphocytic pleocytosis, slightly elevated protein and normal glucose. MRI of the brain showed a hyperintense lesion in left ganglio-capsular region on the fluid attenuation inversion recovery sequence with perilesional oedema and mild midline shift. Haemorrhage was seen in the region on susceptibility weighted imaging . The patient was thoroughly investigated for known causes of meningoencephalitis, but the diagnosis of scrub typhus was delayed till the 10th day of illness. She was treated with doxycycline for 2 weeks and had marked improvement, both clinically and radiologically. Literature review has revealed that although meningoencephalitis in scrub typhus is not uncommon, such atypical lesions on brain MRI are a rarity. Serial imaging was performed to document the disease progression and resolution on treatment.

Correlation of Pancreatic T1 Values Using Modified Look-Locker Inversion Recovery Sequence (MOLLI) with Pancreatic Exocrine and Endocrine Function

Quantifying myocardial T1 values has been useful for detecting and characterizing fibrotic appearance in myocardial infarction, focal scars, and non-ischemic cardiomyopathies. Since pancreatic exocrine function decreases with chronic pancreatic fibrosis advancement, this study examined the correlation between pancreatic T1 values and pancreatic exocrine and endocrine insufficiency. Methods: Thirty-two patients underwent abdominal contrast-enhanced MRI in our department between October 2017 and February 2019. We evaluated the T1 values of the pancreas using a modified Look-Locker inversion recovery sequence (MOLLI), pancreatic exocrine insufficiency (PEI) by fecal elastase 1 (FE1) values, and pancreatic endocrine insufficiency using fasting insulin and blood glucose levels to calculate the HOMA-β. This trial is registered in the UMIN Clinical Trials Registry as UMIN 000030067. Results: The median cohort (9 males and 23 females) age was 71 (range: 49–84) years. Eighteen patients had pancreatic cysts, three had alcohol-induced chronic pancreatitis, three had pancreatic cancer, and eight possessed other pancreatic features (two patients each with autoimmune pancreatitis, acute pancreatitis, or a bile duct tumor, one with idiopathic chronic pancreatitis, and one healthy control with negative findings). The median pancreatic T1 value measured by the MOLLI was 857.5 ms (597–2569). A significant negative correlation was found between the T1 mapping and FE1 values (r = 0.69, p < 0.01), with none for the T1 with HOMA-β or serum albumin, triglycerides, or body mass index. Conclusions: the pancreatic T1 values correlated significantly with pancreatic exocrine function and might be useful in PEI diagnosis.