Periventricular Calcification

Susan I. Blaser, MD, FRCPC

DIFFERENTIAL DIAGNOSIS

Common

TORCH, General
- Congenital CMV
- Congenital Toxoplasmosis
- Congenital Herpes Encephalitis
- Congenital HIV
- Congenital Rubella
Tuberous Sclerosis Complex

Less Common

Neurocysticercosis
Tuberculosis
Ventriculitis (Chronic)
Germinal Matrix Hemorrhage

Rare but Important

Radiation and Chemotherapy
Pseudo-TORCH
- Aicardi-Goutières Syndrome
- Coats-Plus Syndrome

ESSENTIAL INFORMATION

Key Differential Diagnosis Issues

Look for associations
- Brain destruction
- Malformations
- Other loci of calcification
- History

Helpful Clues for Common Diagnoses

TORCH, General
- Classic acronym for congenital infections
  - Caused by transplacental transmission of pathogens
  - Toxoplasmosis
  - Rubella
  - Cytomegalovirus
  - Herpes
  - All cause parenchymal calcifications
  - Most can cause lenticulostriate mineralization, vasculopathy
  - Some (CMV) cause migrational defects
  - Some (syphilis, herpes) cause meningitis, meningoencephalitis
  - Some (e.g., CMV) cause germinolytic cysts
  - Others (e.g., rubella, HSV) cause striking lobar destruction/encephalomalacia
- Congenital HIV, syphilis also considered part of TORCH
- Consider congenital HIV
  - If bilateral symmetric basal ganglia calcifications identified in child > 2 months old
- If congenital infection is diagnostic consideration, obtain NECT to detect calcifications
Congenital CMV
- Most common cause of intrauterine infection in USA
- Timing of infection predicts pattern of damage
- Hypomyelination
- Cortical gyral anomalies
- Microcephaly
- Symmetric periventricular calcifications in 30-70%
Congenital Toxoplasmosis
- Periventricular and scattered calcifications
- Hydrocephalus (colpocephaly-like)
Congenital Herpes Encephalitis
- Calcification pattern varies in HSV2
  - Asymmetric periventricular
  - Scattered periventricular and deep gray
  - Subcortical white matter and cortex
  - Calcification pronounced in foci of hemorrhagic ischemia
  - Like rubella, rare cause of “stone brain”
- Brain atrophy or cystic encephalomalacia
  - Focal or diffuse
Congenital HIV
- Vertical HIV infection
- Basal ganglia calcifications
- Atrophy
- Consider congenital HIV
  - If bilateral symmetric basal ganglia calcifications present and child is > 2 months old
Congenital Rubella
- Periventricular and scattered calcifications
- Scattered or hazy basal ganglia calcifications
- Rarely “stone brain”
  - Extensive gyral calcification
  - Gliosis
- Micro-infarcts
Tuberous Sclerosis Complex
- a.k.a. Bourneville disease
- Classic triad
  - Mental retardation
  - Epilepsy
  - Adenoma sebaceum
- Look for cutaneous markers of tuberous sclerosis
- Subependymal nodules
  - Variable-sized periventricular calcifications
- Cortical tubers also calcify

Helpful Clues for Less Common Diagnoses

Neurocysticercosis
- Best clue: Dot inside cyst
- Usually convexity subarachnoid space
- Also gray-white junction, intraventricular
- Nodular calcified (healed) stage
  - Shrunken calcified nodule
Tuberculosis
- Best diagnostic clue
  - Basal meningitis
  - Pulmonary tuberculosis
- Acute
  - Typically basal meningitis
  - ± localized CNS tuberculoma
- Chronic
  - Residual pachymeningeal
  - ± localized calcifications
- “Target” sign
  - Calcification surrounded by enhancing rim (not specific)
Ventriculitis (Chronic)
- Areas of prior hemorrhagic infarction prone to dystrophic calcification
Germinal Matrix Hemorrhage
- Occasional ependymal, germinal matrix calcific foci

Helpful Clues for Rare Diagnoses

Radiation and Chemotherapy
- History
- Mineralizing microangiopathy
Pseudo-TORCH
- Aicardi-Goutières Syndrome
  - “Mendelian mimic of congenital infection”
  - Multifocal punctate calcifications
  - Variable locations including periventricular white matter, basal ganglia, dentate nuclei
  - Elevated CSF interferon (IFN-α)
  - TREX1 mutations in some
- Coats-Plus Syndrome
  - a.k.a. cerebroretinal microangiopathy with calcifications and cysts
  - Ocular coats: Retinal telangiectasia and exudate
  - CNS small blood vessel calcification
  - Extensive thalamic and gyral calcification
  - Defects of bone marrow and integument
  - Growth failure