Transient global amnesia and hippocampal diffusion restriction: an overlooked radiological finding.

Transient global amnesia (TGA) is characterized by isolated sudden anterograde amnesia. Diffusion restriction can be observed in the hippocampus on DWI-MRI at varying rates in TGA patients. This study analyzes the prevalence and characteristics of the hippocampal diffusion restriction (HDR), its relationship with vascular risk factors, and the prevalence of lesions overlooked in routine reports. 91 patients diagnosed with TGA at a tertiary hospital between 2011 and 2022 were evaluated retrospectively. The mean age was 64.8 ± 7.3 years, and 63.7% of patients were female. 75.8% of the patients had at least one vascular risk factor. Focal diffusion restriction was detected in 17 patients (18.5%) on DWI-MRI, with only one being extra-hippocampal. 81.2% of HDR was detected when DWI-MRI scan was performed between 12 and 96 h after the onset of symptoms. HDR was detected most when the imaging was performed in 24 to 48 h (p = 0.03). There was no correlation between the duration of symptoms and the detection rates of HDR (p = 0.55). In 9 patients (53% of 17) diffusion restriction was not specified in routine radiology reports. Although focal ischemia, venous flow abnormalities, migraine and epileptic phenomena have been suggested in its etiology, TGA is a clinical condition of which pathophysiology has not been determined clearly. Signal changes observed in DWI-MRI has led to discussions that cerebrovascular etiology may play a role, yet more comprehensive studies are required to prevent and manage TGA. HDRs can be overlooked in routine reports. Therefore, the DWI-MRI images of patients with TGA should be examined vigilantly.

Do Mean Platelet Volume and Platelet Distribution Width Have An Association with White Matter Hyperintensities in Migraine Patients?

Objective: Increased prevalence of white matter hyperintensities (WMH) is reported in migraine patients; however, the pathophysiology and the progression of these lesions are not definitely clear. Mean platelet volume (MPV) and platelet distribution width (PDW) are easily obtained markers for platelet activity. The aim of this study is to evaluate the relationship between the presence of WMH and MPV and PDW in patients with migraine in order to determine the role of platelet activity in the pathophysiology of WMH. Methods: Patients who were admitted to the neurology outpatient clinics of Baskent University Hospital from January 2011 to December 2015 with migraine and between 18 and 55 years of age were evaluated retrospectively. The blood samples were taken and total blood count parameters including MPV and PDW were analyzed. Brain magnetic resonance images were evaluated. Results: Totally, 218 patients were evaluated in this study. Forty-eight (22.0%) patients had WMH in the brain magnetic resonance imaging. In patients with WMH, the median of age was higher than the patients without WMH and the difference was statistically significant (P < 0.05). There was no statistically significant difference between MPV, PDW values, and the presence of WMH. Conclusions: There are multiple theories suggested for the mechanism of WMH, but the major cause and pathophysiology are still undetermined. Our data suggested that increased platelet activity is insufficient by itself to explain the pathophysiology of WMH in migraine patients and to improve the knowledge on this issue further large longitudinal studies should be performed.

Listeria Rhombencephalitis and Infratentorial Brain Abcesses in a Young Adult with Stroke Like Presentation.

Rhombencephalitis refers to the inflammation of rhombencephalon, and Listeria monocytogenes is one of the causes of infectious rhombencephalitis. Listeria rhombencephalitis is a rare and severe infection with high mortality and morbidity. As the disease can present with a variety of neurological symptoms and nonspecific laboratory tests, it can easily be misdiagnosed. Sudden onset of neurological signs without fever can resemble stroke. Magnetic resonance imaging can be useful in patients for confirmation of the diagnosis and during the follow-up. Early diagnosis and treatment are especially important for improvement of the outcomes. Here we report a case with stroke-like presentation that was diagnosed as Listeria rhombencephalitis in follow-up and present the serial brain magnetic resonance imaging features.

Relationship between white matter hyperintensities and retinal nerve fiber layer, choroid, and ganglion cell layer thickness in migraine patients.

Aim To compare the relationship between white matter hyperintensities (WMH) on brain magnetic resonance imaging and retinal nerve fiber layer (RNFL), choroid, and ganglion cell layer (GCL) thicknesses in migraine patients and healthy subjects. We also assessed the role of cerebral hypoperfusion in the formation of these WMH lesions. Methods We enrolled 35 migraine patients without WMH, 37 migraine patients with WMH, and 37 healthy control subjects examined in the Neurology outpatient clinic of our tertiary center from May to December 2015. RFNL, choroid, and GCL thicknesses were measured by optic coherence tomography. Results There were no differences in the RFNL, choroid, or GCL thicknesses between migraine patients with and without WMH ( p > 0.05). Choroid layer thicknesses were significantly lower in migraine patients compared to control subjects ( p < 0.05), while there were no differences in RFNL and GCL thicknesses ( p > 0.05). Conclusions The 'only cerebral hypoperfusion' theory was insufficient to explain the pathophysiology of WMH lesions in migraine patients. In addition, the thinning of the choroid thicknesses in migraine patients suggests a potential causative role for cerebral hypoperfusion and decreased perfusion pressure of the choroid layer.

Spontaneous Spinal Subarachnoid Hemorrhage with Residual Arachnoid Cyst: A Case Report.

Spinal subarachnoid hemorrhage is a rare condition that usually occurs because of secondary causes and idiopathic spontaneous ones are extremely rare. We report a 56-year-old woman who presented with severe headache, neck pain and urinary retention. Magnetic resonance imaging revealed subarachnoid hemorrhage that extended from T1 to lumbar vertebrae. She was treated conservatively and symptoms were resolved within 1 month. An asymptomatic arachnoid cyst was observed on the follow-up magnetic resonance imaging after 3 months with no neurologic deterioration. She was still stable clinically and radiologically at the end of 19 months. Spinal subarachnoid hemorrhage is a surgical emergency, although in some cases a conservative approach may be useful.