iRadiology最新文献

White matter hyperintensities (WMH) are very widespread in older adults and are imaging features of both cerebral small-vessel disease and white matter microstructural impairments. Recent studies have demonstrated a close association between WMH and some common diseases in older adults, including Alzheimer's disease and hypertension. Thus, studies of WMH are important for avoiding the occurrence of these diseases and improving the health status of older adults. This review summarizes the literature relating to WMH in terms of epidemiology, clinical presentation, pathogenesis, imaging features, and therapy. It also analyzes the limitations of present studies and provides perspectives on future directions.

A 53 year old male presented to his local doctor with an acute knee injury, limited knee movement and a haemoarthrosis. Patient did not have calf tenderness or clinical suspicion for deep vein thrombosis (DVT). He was referred for a routine acute knee magnetic resonance imaging (MRI) scan. This MRI demonstrated a full thickness anterior cruciate ligament tear with additional findings, of a probable incidental DVT. The relevant MRI findings suggestive of DVT in this case included perivascular edema and expanded caliber of the involved medial gastronomical veins on the axial proton density fat suppressed sequence (Figure 1), increased intraluminal T1 signal within the involved segment of vein and susceptibility within the vein related to haemosiderin deposition/blood products on the gradient echo sequence. DVTs are rarely reported on MRI scans. Awareness of suspicious imaging findings for both radiologists and surgeons may aid in recognition of incidental DVTs and improve management.

Karoline Kant: writing–original draft (equal). Michael Facek: writing–review & editing (equal). Craig Buchan: conceptualization (equal), writing–review & editing (equal).

The authors have nothing to report.

The patient has provided consent for publication of this image.

The authors declare no conflicts of interest.

Transcranial focused ultrasound (tFUS) is an emerging modality with strong potential for non-invasively treating brain disorders. However, the inhomogeneity and complex structure of the skull induce substantial phase aberrations and pressure attenuation; these can distort and shift the acoustic focus, thus hindering the efficiency of tFUS therapy. To achieve effective treatments, phased array transducers combined with aberration correction algorithms are commonly implemented. The present report aims to provide a comprehensive review of the current methods used for tFUS phase aberration correction. We first searched the PubMed and Web of Science databases for studies on phase aberration correction algorithms, identifying 54 articles for review. Relevant information, including the principles of algorithms and refocusing performances, were then extracted from the selected articles. The phase correction algorithms involved two main steps: acoustic field estimation and transmitted pulse adjustment. Our review identified key benchmarks for evaluating the effectiveness of these algorithms, each of which was used in at least three studies. These benchmarks included pressure and intensity, positioning error, focal region size, peak sidelobe ratio, and computational efficiency. Algorithm performances varied under different benchmarks, thus highlighting the importance of application-specific algorithm selection for achieving optimal tFUS therapy outcomes. The present review provides a thorough overview and comparison of various phase correction algorithms, and may offer valuable guidance to tFUS researchers when selecting appropriate phase correction algorithms for specific applications.

A 53 year-old woman presented with a 4 year history of recurrent dizziness episodes. Each episode lasted approximately 1 week and was not accompanied by nausea, or vomiting. Comprehensive vestibular assessments, including vestibular function tests, Dix–Hallpike maneuver, and the roll test, were all negative. The patient reported no atherosclerotic risk factors, such as hypertension, hyperlipidemia or diabetes mellitus, and her family history was unremarkable. General physical and neurological examinations were unremarkable. Central causes of dizziness were considered. A computed tomography angiography of the head revealed a plexiform configuration in the M1 segment of the right middle cerebral artery (MCA), with no other significant abnormalities (Figure 1a). Moyamoya disease was considered a possible diagnosis. Subsequent digital subtraction angiography demonstrated the absence of a normal right M1 segment, with a twig-like vascular network connecting to the distal MCA (Figure 1b,c). Additionally, the right carotid canal was found to be smaller than the left, suggesting potential congenital variants consistent with rete MCA (Figure 1d). The patient was treated with betahistine 6 mg three times daily, resulting in alleviation of her dizziness.

Rete MCA, also known as twig-like MCA, is a rare vascular anomaly characterized by the presence of a twig-like arterial network in the M1 segment of the MCA. This variant may present with either hemorrhagic or ischemic strokes, or, as in this case, with no clinical symptoms. The primary differential diagnoses for rete MCA include moyamoya disease/syndrome and atherosclerotic occlusion. In contrast to these conditions, rete MCA is typically unilateral, occurs exclusively in the M1 segment with a distinctive twig-like appearance, and does not involve atherosclerotic risk factors. Notably, it preserves the caliber and flow of the distal MCA. In surgical settings, rete MCA often presents as a white cord-like structure. Accurate diagnosis is essential, particularly for asymptomatic patients, to avoid unnecessary concerns about occlusion. For symptomatic individuals, surgical intervention may be considered.

Yongming Wang: writing–original draft (lead). Xi Chen: writing–original draft (equal). Junsheng Liu: writing–review and editing (equal).

This study was approved by the Ethics Committee of The People's Hospital of Pingchang in 2024 (Approval Number: 20240731-121).

The patient provided informed consent for the publication of the case.

The authors declare no conflicts of interest.