Radiology MRI

  An absent posterior pituitary bright spot on MRI is a classic neuroradiology finding, but it always demands a deeper look. In the latest case breakdown on the Radiant Pixels YouTube channel, we review a compelling case of a 30-year-old patient presenting with clinical diabetes insipidus. When evaluating central diabetes insipidus, the MRI protocol must be meticulous. This case beautifully demonstrates how to systematically evaluate the adenohypophysis, neurohypophysis, and the pituitary stalk to differentiate between structural, congenital, and inflammatory pathologies. Key sequences highlighted in the video include: Coronal T2-weighted images to evaluate local anatomy and the optic chiasm. Sagittal T1-weighted images (pre-contrast) to check for the normal intrinsic high signal intensity of the posterior pituitary. Dynamic post-gadolinium T1 images (sagittal and coronal) to assess enhancement patterns and track pathology. Major Teaching Points Covered in the Video 1. The Abse...

  In this case presentation, we review the imaging findings of a 50-year-old male presenting with balance issues, visual disturbances, and general fatigue. While aqueductal stenosis is often associated with pediatric populations, adult-onset presentation due to an ependymal web is a critical diagnostic entity to recognize. Check out the full breakdown and see the high-resolution sequences in the video below: Key Imaging Findings Ventriculomegaly: The ventricular system is widened supratentorially, with an Evans' index of 0.36 . The temporal horns and cerebral sulci remain within normal limits. Secondary Signs of Hydrocephalus: Notable upward expansion of the corpus callosum and very faint transependymal leakage (interstitial edema). The Web: High-resolution multiplanar reconstruction (MPR) and sagittal FLAIR sequences reveal a thin membrane localized to the lower one-third of the aqueduct . Caliber Mismatch: The aqueduct measures approximately 4 mm at the level of the superior ...

  When evaluating neuroimaging for epilepsy, finding a clear culprit is always a breakthrough. But what happens when the images reveal a more complex story—a "double whammy" of potential epileptogenic foci? In the upcoming video on Radiant Pixels , we dive into a fascinating, longitudinal case of an epilepsy patient followed over a 12-year period (from age 30 to 42). This case beautifully illustrates classic mesial temporal sclerosis (MTS) while presenting an intriguing secondary structural pathology that poses a classic chicken-and-egg dilemma. The Primary Suspect: Mesial Temporal Sclerosis (MTS) The journey begins with a look back at the patient's scans from 12 years ago. On the coronal sequences—specifically using an inversion recovery sequence highly sensitive to anatomical structures—we see the definitive hallmarks of mesial temporal sclerosis : Volume Loss: Clear, asymmetric atrophy of the left hippocampus. Hyperintensity: Markedly increased signal intensity on t...

  A new case presentation is now live on the Radiant Pixels YouTube channel. In this session, we walk through an excellent example of a normal vascular anatomical variant that frequently catches the eye during routine scans: a Developmental Venous Anomaly (DVA) located in the cerebellum. When evaluating a suspected DVA, a systematic, multi-sequence approach is essential to confirm the diagnosis and rule out complications. Here is a brief summary of the key diagnostic imaging points highlighted in the video: Non-Enhanced CT: The anomaly may initially present as a subtle high-density structure, prompting further MR investigation. Standard MRI (T1, T2, FLAIR): Look for a tubular structure exhibiting the classic "caput medusae" configuration—a cluster of small branching vessels. These typically show a low signal on T2 and FLAIR. Crucially, the surrounding brain parenchyma should appear anatomically normal, lacking any signs of gliosis, volume loss, or old infarctions. Time-of-...

  Welcome back to the blog. Following up on my previous posts, Monkey looking at cerebellum and Small  Vestibular Schwannoma , I have just published a new companion video on the Radiant Pixels YouTube channel that brings these concepts to life. If you are looking to sharpen your diagnostic skills regarding internal acoustic canal pathology and anatomy, this case presentation is for you. What to Expect in the New Video In this latest upload, I walk through a classic presentation of a 75-year-old patient experiencing left-sided hearing loss. We review the imaging step-by-step, starting with the thin-slice T2 sequences that are highly sensitive for evaluating the internal acoustic canals, all the way through to the contrast-enhanced T1 coronal slices. Key highlights of the case include: Identifying a normal vascular AICA-loop at the level of the porus acusticus and understanding when to note it for the clinician. Locating and measuring a small 5 mm by 3 mm dark structure plugge...

  Evolution of Hemorrhagic Infarctions on MRI Welcome to another intriguing radiology case study. In our latest release on the Radiant Pixels YouTube channel, we dive into a comparative MRI analysis of an 80-year-old patient, examining scans taken five months apart. This case provides a fantastic look at the evolution of subacute infarctions and the often-perplexing behavior of contrast-enhancing areas over time. The Initial Findings and the Mystery Enhancement The baseline exam reveals distinct areas of tissue loss and gliosis, accompanied by contrast enhancement in the medial parts of the right occipital lobe. We also observe similar, smaller contrast-enhancing areas in the right lateral frontal lobe, specifically at the level of the inferior frontal gyrus. The initial radiological report strongly suggested these locations were indicative of subacute to old infarctions within the posterior cerebral artery territory. However, the persistent contrast enhancement presented a specif...