Magnetic Resonance Imaging (MRI) Practice Test

What is the optimal imaging plane for evaluating Arnold Chiari Malformation?

1. Coronal

2. Sagittal

3. Axiolateral

4. Transversal

The correct answer is: Sagittal

The optimal imaging plane for evaluating Arnold Chiari Malformation is the sagittal plane. This positioning provides a clear view of the posterior fossa, cerebellum, and brainstem, which are the key areas affected by this condition. By utilizing the sagittal plane, radiologists can assess the herniation of the cerebellar tonsils through the foramen magnum and any associated structural anomalies. In the case of Arnold Chiari Malformation, the assessment typically focuses on relationships between the cerebellum, brainstem, and spinal canal, making the sagittal view particularly valuable. It allows for visualization of the length of Chiari malformation, and reveals any potential obstructive events to cerebrospinal fluid flow. The other imaging planes, while useful in different contexts, do not provide the same level of detail for the specific abnormalities associated with Arnold Chiari Malformation. For example, a coronal view may be beneficial for evaluating facial structures but lacks the alignment necessary for assessing posterior fossa relationships. Axiolateral and transversal planes are not standard for this condition, as they do not offer the longitudinal perspective needed to adequately understand brainstem and cerebellar positioning visibly impacted by the malformation.