Clinical and Imaging Findings in Four Patients with the Diagnosis of PmA Compared with that of Chiasmatic/Hypothalamic PA
| MR Characteristics | PmA Patients | Typical PA in Chiasmatic/Hypothalamic Region | |||
|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | ||
| Composition solid versus cystic | >70% solid | >90% solid | 100% solid | 100% solid | Mostly solid possibly cystic |
| Mass effect and encasement of surrounding vessels at time of presentation | Moderate | Extensive | Extensive | Moderate | Mild to moderate |
| T1 signal intensity | Hypointense | Hypointense | Hypointense | Hypointense | Hypointense, cystic portion CSF isointense |
| T2 signal intensity | Hyperintense | Hyperintense | Hyperintense | Hyperintense | Hyperintense |
| Contrast enhancement of solid portion and cyst wall | Homogenous and thick peripheral enhancement | Homogenous | Homogenous | Homogenous | Variable, may not enhance |
| Basilar meningeal enhancement | No | Yes | Yes | Yes | No |
| Spinal meningial enhancement | n/a | Yes | Yes | n/a | No |
| Extension of T2 to deep gray/white matter | Yes | No | No | Yes | Yes |
| Location (optic chiasm/hypothalamus) | Optic chiasm/hypothalamus | Optic chiasm/hypothalamus | Optic chiasm/hypothalamus | Optic chiasm/hypothalamus | Optic chiasm/hypothalamus |
| Calcification, ossification | No | No | No | No | Yes (10%) |
| Hydrocephalus | Yes (mild to moderate) | None | Mild (slight prominence temp. horns) | None | Mild |
| Necrosis | No | No | Yes | Yes | No |
| Hemorrhage | No | No | No | No | No |
| Association with neurofibromatosis 1 | No | No | No | No | Yes |
| Age at presentation/sex | 2 years/boy | 5 months/boy | 2 years/girl | 10 months/boy | Childhood (2–6 years) |
| Clinical presentation | Failure to thrive | Feeding difficulties | Failure to thrive | Developmental delay | Nonspesific, similar to PMA |