Neuroglial Cysts (Glioependymal Cysts, Neuroepithelial Cysts) MRI
Neuroglial cysts, also known as glioependymal or neuroepithelial cysts, are rare benign cystic lesions that occur within the central nervous system (CNS). These cysts are thought to originate from neuroglial tissue, likely due to developmental anomalies during embryogenesis. They can arise anywhere within the CNS, including the brain and spinal cord.
Symptoms
The symptoms of neuroglial cysts depend on their size and location. Many cysts are asymptomatic and discovered incidentally during imaging for other reasons. When symptoms do occur, they may include:
- Headaches: Due to increased intracranial pressure.
- Seizures: If the cysts irritate the surrounding brain tissue.
- Neurological Deficits: Such as weakness, sensory loss, or coordination problems.
- Hydrocephalus: If the cyst obstructs cerebrospinal fluid pathways, leading to increased fluid accumulation in the brain.
- Cognitive or Behavioral Changes: Depending on the cyst’s location.
Diagnosis
The diagnosis of neuroglial cysts typically involves imaging studies and sometimes histological examination:
- Magnetic Resonance Imaging (MRI): The preferred imaging modality, MRI provides detailed images of the brain and spinal cord, helping to identify the cyst’s location, size, and characteristics.
- Computed Tomography (CT): Useful in emergency settings or when MRI is contraindicated. CT can detect cystic lesions but offers less detail compared to MRI.
Treatment
The treatment of neuroglial cysts depends on the size, location, and symptoms. Options include:
- Observation: Asymptomatic or incidentally found cysts may only require regular monitoring with periodic MRI scans to ensure they do not grow or cause symptoms.
- Surgical Intervention: Symptomatic cysts often necessitate surgical removal. The surgical approach depends on the cyst’s location and the patient’s overall health:
- Craniotomy: Opening the skull to access and remove the cyst.
- Endoscopic Surgery: Minimally invasive technique using an endoscope to drain or remove the cyst.
MRI appearance of late subacute hemorrhage
MRI T2 Appearance of Brain Neuroglial Cysts
On T2-weighted MRI images, neuroglial cysts are characterized by hyperintense (bright) signals due to their fluid content, which is similar to cerebrospinal fluid (CSF). The high signal intensity on T2-weighted sequences helps in the identification and delineation of these cysts against the darker background of the surrounding brain tissue. The well-defined borders of the cysts are evident, and there is typically no surrounding edema or mass effect. This hyperintense appearance on T2-weighted images aids in confirming the cystic nature of the lesion.
MRI FLAIR Appearance of Brain Neuroglial Cysts
On Fluid-Attenuated Inversion Recovery (FLAIR) MRI images, neuroglial cysts generally appear as hypointense (dark) regions due to their fluid content, distinguishing them from other pathological processes that might appear hyperintense on FLAIR images. The absence of surrounding edema or enhancement further supports the benign nature of these cysts.
MRI DWI Appearance of Brain Neuroglial Cysts
Neuroglial cysts appear bright (hyperintense) on the b0 image due to their fluid content and long T2 relaxation times, making them stand out. On the b1000 image, these cysts appear dark (hypointense) because the high b-value suppresses the signal from the cysts, resulting in reduced signal intensity due to free water diffusion. On ADC maps, neuroglial cysts appear bright (hyperintense) as the free diffusion of water within the cyst leads to high ADC values, translating into a bright signal.
MRI T1 Appearance of Brain Neuroglial Cysts
On T1-weighted MRI images, neuroglial cysts typically appear as well-defined, hypointense (dark) lesions relative to the surrounding brain tissue. These cysts are filled with CSF-like fluid, which has a low signal intensity on T1-weighted sequences. The clear boundaries and homogeneity of the hypointense signal help distinguish neuroglial cysts from other intracranial lesions. There is usually no associated surrounding edema or mass effect, making them benign and non-enhancing features on T1-weighted images.
MRI T1 Post-Contrast Appearance of Brain Neuroglial Cysts
After the administration of contrast material, T1-weighted MRI images of neuroglial cysts typically show no enhancement, maintaining their hypointense (dark) appearance. The lack of contrast enhancement indicates that these cysts do not have a significant vascular component and are not associated with active inflammation or malignancy. The clear, non-enhancing borders of neuroglial cysts on post-contrast images further aid in distinguishing them from other enhancing intracranial lesions, confirming their benign nature
T2 axial image shows Neuroglial Cysts (Glioependymal Cysts, Neuroepithelial Cysts)
FLAIR axial image shows Neuroglial Cysts (Glioependymal Cysts, Neuroepithelial Cysts)
T1 coronal image shows Neuroglial Cysts (Glioependymal Cysts, Neuroepithelial Cysts)
T2 sagittal image shows Neuroglial Cysts (Glioependymal Cysts, Neuroepithelial Cysts)
DWI b0 image shows Neuroglial Cysts (Glioependymal Cysts, Neuroepithelial Cysts)
DWI b1000 image shows Neuroglial Cysts (Glioependymal Cysts, Neuroepithelial Cysts)
DWI ADC map image shows Neuroglial Cysts (Glioependymal Cysts, Neuroepithelial Cysts)
References
- Mustapha, O., Allali, N., Latifa, C., & El Haddad, S. (2021). Epilepsy as a Presentation of a Neuroglial Cyst Associated with Dysgenesis of Corpus Callosum in a Child. Case Reports in Radiology, 2021, 6675071. https://doi.org/10.1155/2021/6675071
- Pereira, R. G., Ribeiro, B. N. F., Hollanda, R. T. de L., Almeida, L. B. de, Simeão, T. B., & Marchiori, E. (2021). Non-neoplastic intracranial cystic lesions: Not everything is an arachnoid cyst. Radiologia Brasileira, 54(1), 49-55.