An Arnold-Chiari Type II Malformation

question 19

Multiple Choice

An Arnold-Chiari type II malformation:

• A)Is not associated with a defect of the lower neural tube.
• B)Consists of herniation of the cerebellar tonsils into the vertebral canal.
• C)Is associated with progressive hydrocephalus.
• D)Usually manifests during adolescence or early adulthood.

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Definitions:

Eyelids

Thin folds of skin that cover and protect the eye; they help to spread moisture (tears) over the surface of the eye when blinking.

Retina

The light-sensitive layer of tissue at the back of the inner eye, responsible for converting light into neural signals for visual recognition.

Photoreceptor Cells

Specialized neurons in the retina that convert light into signals that can stimulate biological processes.

Innermost Tunic

The deepest layer of a structure, often referring to the inner layer of a blood vessel or other tubular organ.