# Favorable Outcomes in a Rare Case of Chiari Malformation Type III: A Clinical Report

**Authors:** Renz Marion M Alemania, Maria Estrella G Ibe-Ilustre

PMC · DOI: 10.7759/cureus.84482 · 2025-05-20

## TL;DR

A young child with a rare and severe brain condition called Chiari malformation type III showed a positive recovery after surgery.

## Contribution

This case report highlights a favorable outcome in a rare Chiari malformation type III case following neurosurgical intervention.

## Key findings

- The patient had a bony defect and herniation consistent with Chiari malformation type III.
- Despite the condition's typically poor prognosis, the patient showed favorable outcomes after surgery.
- The case emphasizes the potential for positive post-surgical results in this rare condition.

## Abstract

This report details the case of a 1-year and 11-month-old Filipino female patient who presented with a persistent occipital mass that was soft, non-tender, mobile, and lit through upon transillumination. A neurological test revealed a global developmental delay. Neuroimaging revealed a bony defect at the posterior cranial fossa with herniation of the occipital lobe, cerebrospinal fluid, and the meninges, consistent with Chiari malformation type III, a rare and severe form accounting for less than 1% of Chiari malformations. While this condition typically carries a poor prognosis, the patient showed a favorable outcome following neurosurgical intervention.

We present this case to share our clinical experience with this exceedingly rare condition and highlight its potential for positive post-surgical outcomes.

## Linked entities

- **Diseases:** Chiari malformation type III (MONDO:0022715)

## Full-text entities

- **Diseases:** Chiari Malformation Type III (MESH:D001139), bony defect (MESH:D018213), developmental delay (MESH:D002658)
- **Species:** Homo sapiens (human, species) [taxon 9606]

## Figures

1 figure with captions in the complete paper: https://tomesphere.com/paper/PMC12178446/full.md

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Source: https://tomesphere.com/paper/PMC12178446