# December 2025 – Case 1

- Link: https://isnr.in/december-2025-case-1/
- Published: 2025-12-08T01:57:00+05:30
- Author: ISNR

## CASE HISTORY

9-year-old female with URI for 1 week, fever for 3 days, seizures and altered sensorium
for 1 day.

Known cerebellar malformation, unrelated to current event.

## CASE CONTRIBUTED BY

Dr. **Reettika Chanda**, DMRD, MD, DNB, MNAMS
Clinical Fellowship in Diagnostic 
Neuroradiology, University of Calgary, CAAssociate Professor,Department of Radiodiagnosis,
Under the Division of Clinical Radiology,Christian Medical College, Vellore

![](https://isnr.in/wp-content/uploads/2025/12/case-of-the-month-december-2025-1.
jpg)

## **Diagnosis: Acute Necrotizing Encephalopathy of Childhood (ANEC)**

#### **Noncontrast CT:**

 * Multifocal parenchymal densities involving both grey-white matter in a nonvascular
   distribution in the supratentorial brain (blue arrows).
 * Diffuse bithalamic swelling and hypodensity (yellow arrows).
 * Basal cisternal effacement and indistinct mamillopontine distance on sagittal
   sections

#### **Contrast enhanced CT:**

 * Patent internal cerebral veins (green arrows).

#### **Discussion**

 * This case highlights the CT findings of ANEC in an acute clinical setting.
 * Given the history of rapid neurological decline following a viral prodrome, these
   CT findings are diagnostic of ANEC.
 * Patency of the cerebral veins rules out internal cerebral vein thrombosis as 
   a cause of bithalamic involvement.
 * Patients are often too unwell to undergo MRI, which may also provide limited 
   additional diagnostic value; however, if performed, it can demonstrate the characteristic
   trilaminar sign in the thalami (yellow arrows), along with variable degrees of
   parenchymal involvement (blue arrows).

![](https://isnr.in/wp-content/uploads/2025/12/case-of-the-month-december-2025-1-
2.jpg)

#### **References**

 * Dar, Mohammad Irfan; Bhat, Vidushi; Bhardwaj, Surbhi. Acute necrotizing encephalopathy
   of childhood as a complication of dengue infection: A case report. Journal of
   Pediatric Critical Care 10(3):p 121-123, May–Jun 2023. | DOI: 10.4103/jpcc.jpcc_10_23
 * Vanjare HA, Selvi BT, Karuppusami R, Manesh A, Gunasekaran K, Prabhakar AT, Mannam
   P, Jasper A. Clinical and Radiologic Findings of Acute Necrotizing Encephalopathy
   in Young Adults. AJNR Am J Neuroradiol. 2020 Dec;41(12):2250-2254. doi: 10.3174/
   ajnr.A6803. Epub 2020 Oct 29. PMID: 33122207; PMCID: PMC7963253.
 * St-Amant M, Najjar R, Fortin F, Muzio BD, Glick Y, Yap J, et al Acute necrotizing
   encephalopathy. Reference article, Radiopaedia.org https://doi.org/10.53347/rID-
   24838 Available from: https://radiopaedia.org/articles/24838