Dr. Nikhil R M (NeuroRad)

Hi, I’m Dr. Nikhil R M — Pediatric Neuroradiologist & Director @ Sigma Imaging. Sharing insights on Neuro MRI, ASL Perfusion & Pediatric Brain Imaging. SPIN Fellow (Pediatric Neuroradiology) | #NeuroRad #AIrad #Radiology Let’s connect to learn, share & collaborate! DMs Open.

@nirmalregency Thank you, sir. Your questions made this case far more educational. The key rescue was venous-territory logic + SWI followed by targeted CE-MRV. Grateful for the discussion. 🙏

✅ Grand: Seldom we see, often misidentify Deep CVT vis-a-vis the commoner, Superficial CVT. @mehtanikhil has enlightened us for those who work in the tropics lest we mistake them as Flavivirus Encephalitides: 🔺Dengue 🔺JE 🔺KFD 🔺Murray Valley 🔺WNV 🔺Zika 🔺Omsk ... ♥️🙏

A supreme review for those interested in 'Bithalamic Pathology Imaging' ajronline.org/doi/10.2214/AJ…

🧵 SPIN Tweetorial Wednesday Can MRI detect abnormal brain iron metabolism in children with Global Developmental Delay before structural abnormalities appear? A new study suggests that Quantitative Susceptibility Mapping (QSM) may provide an objective imaging biomarker. 👇

@nirmalregency Sorry the images did not reflect in the previous posts.

Thank you, sir @nirmalregency. Follow-up CE-MRV: ICV/straight sinus filling defect + CE-FLAIR thrombus in the left transverse sinus. SWI showed cerebellar hemorrhagic venous changes (also in the previous attached images). Pattern fits deep venous thrombosis. Clinical feedback: improving after heparinisation.

1/2 Case story 🧠 Headache, vomiting, confusion + fever. CT head normal. MRI showed bilateral thalamic–basal ganglia signal abnormality with hippocampal involvement/enhancement. Trap: fever + deep gray lesions can mimic viral encephalitis.

Sorry the images did not reflect in the previous posts.

Your question also pushed a useful anatomy point: why relative capsular sparing? Thalami/BG drain dominantly to deep venous channels-ICV/straight sinus. Internal capsule has mixed striate/basal venous drainage + collaterals, so PLIC can be relatively spared while ALIC/genu are involved.

ASPNR: Case of the Week A 1-year 5-month-old male patient presenting with new onset seizures. bit.ly/4wnbosk Alp Oztek, MD Seattle Children’s Hospital, Seattle, WA#PediNeuroRad #MedEd #FOAMrad #PedsRad

CT scan was done somewhere else, we could only get the report and not the images. Patient came middle of the night for MR Brain and contrast as needed.

@RadioBabz Yes it was done somewhere else.

@mehtanikhil Nice case ! However, I strongly doubt CT scan was normal 😅

@nirmalregency Fascinating history! It’s incredible to reflect on how far we’ve come since Alzheimer’s meticulous neuropathologic observations in 1907. Today, we can visualize very plaques & atrophy described with advanced MRI and PET imaging, bridging his foundational work with new diagnostics

❸ 1907: Bavarian psychiatrist, Alois Alzheimer is credited w/ the 1st published case of “presenile dementia” in a 51♀ 🔜 his superior Emil Kraepelin termed it as Alzheimer’s disease.

⓵ of ⓻🧵 🤔 The previous post: of 72♂ w/ 3 yr gradually ⬆️dementia w/ dressing apraxia & confusional state. x.com/nirmalregency/…

@jjgarnham A good clinico-radiological case correlate @jjgarnham

This patient presented with left-sided internuclear ophthalmoplegia (INO). How can we explain this? 👁️👁️ How normal horizontal eye movements work: ⭐️ To look to the right, the brain (mainly from the left frontal eye field) activates the right horizontal gaze center - in the paramedian pontine reticular formation (PPRF) - located in the pons. ⭐️ The right PPRF stimulates the adjacent right abducens nucleus (CN VI). ⭐️ The right abducens nucleus does two things simultaneously: 1⃣ It sends signals to the right lateral rectus muscle → right eye abducts. 2⃣ It sends interneurons that cross the midline and ascend in the left medial longitudinal fasciculus (MLF) to reach the left oculomotor nucleus (CN III, medial rectus subnucleus) in the midbrain. ⭐️ This activates the left medial rectus muscle → left eye adducts. ⭐️ This ensures both eyes move together smoothly to the right! 👁️❌👁️ What happens with a left MLF lesion? ⭐️ A lesion in the left MLF (whether in the pons or midbrain) interrupts the pathway. ⭐️When looking to the right, the right eye abducts normally (intact right CN VI), BUT... ❌The signal fails to reach the left CN III medial rectus subnucleus through the damaged left MLF. ❌Result: impaired adduction of the left eye (it lags behind or stays near the midline). The left MLF is taken out by this infarct!

@nodisability @nirmalregency We keep DWI / GRE / Zero TE and Dixon in the optional list of the spine protocol with a short pause after the routine scan protocol completes; which is added depending on the clinical details or imaging findings.

@nirmalregency Are we regularly ask for DWI/ ADC for spinal cord? I insist in suspected vascular etiology

Hyperacute flaccid typically a bit asymmetric quadriparesis w/ preserved post column: a rarity. Excellent case presentation. Sometimes the cord also needs a DWI screening.

@nirmalregency Yes, DWI of cord was done on the follow1up which lost the restriction window. The prior outside institution scan DWI spine was done, however was ambiguous due to artefacts!

For those neurorads working more with surgical units….

Take-home: Vigorous activity → back pain → rapid quadriparesis. Think spinal cord infarction - especially with ventral/paramedian medullary + anterior cord involvement and true restricted diffusion for AFP. #SpinalCordMRI #PediatricNeuroradiology #Stroke

Teaching pearl: Anterior horn involvement ≠ always AFM. In acute flaccid paralysis, always integrate: • Clinical clock • Pain at onset • Exertional trigger • DWI/ADC restriction • Vascular topography • Follow-up evolution

🧠Case Twist: An adolescent presented with acute flaccid quadriparesis. Initial clinical differential from pediatric neurology: • Viral anterior horn myelitis / AFM • Inflammatory myelitis • Spinal cord infarction #Neuroradiology #PedsNeuro