Chiari 2

• Neurulation is the primary defect.

• Gaining support from in utero fetal myelomeningocoele repair
• Observed resolution of Chiari Il after closure of the caudal defect

---
config:
  layout: dagre
---
flowchart TD
    A["Lack of expression of<br>surface molecules<br>required for neural<br>tube closure"] --> B["Incomplete occlusion<br>of neural tube → CSF<br>leakage"]
    B --> C["ICP hypotension<br>in the ventricular<br>system"]

    %% Nodes branching from C:
    C --- D2["In the 3rd ventricle"]
    C --- n2["In the lateral ventricle"]
    C --- n6["In the posterior fossa"]

    %% Branches from D2:
    D2 --> n3["3rd ventricle is not<br>inflated adequately"]
    n3 --> n4["Extended<br>thalamic contact"]
    n4 --> n5["Enlargement of massa<br>intermedia"]

    %% Branches from n2:
    n2 --> D1["Germinal matrix<br>disruption at lateral<br>ventricle"]
    D1 --> n1["Malformation of cortical<br>development"]

    %% Branches from n6:
    n6 --> D3["Rhombencephalic<br>vesicle fails to<br>expand"]
    D3 --> E["No induction of<br>posterior fossa<br>perineural mesenchyma"]
    E --> F["Smaller posterior<br>fossa"]
    F --> G["Unable to accommodate<br>developing<br>rhombencephalon"]
    G --> H["Displacement of<br>cerebellum and<br>brainstem"]

    %% Branches from H:
    H --- I["Upwards through<br>tentorium"]
    H --- J["Downwards through<br>foramen magnum"]

    %% Branches from I and J:
    I --> n7["Large tentorial<br>incisura /<br>towering cerebellum"]
    J --> n8["Tonsillar and<br>medullary<br>displacement"]

    %% Node styles:
    style D2 fill:#FFD600
    style n2 fill:#FF6D00
    style n6 fill:#00C853
    style n1 shape:rect
    style n3 shape:rect
    style n4 shape:rect
    style n5 shape:rect
    style n7 shape:rect
    style n8 shape:rect

• Beaking of tectum (2): small arrow

• Hypoplasia of falx