Selected References

Extraaxial Cysts

Ajtai B et al: Imaging of intracranial cysts. Continuum (Minneap Minn). 22(5, Neuroimaging):1553-1573, 2016

Osborn AG, Preece MT. Intracranial cysts: radiologic-pathologic correlation and imaging approach. Radiology. 239(3):650-64, 2006

Arachnoid Cyst

Lee CH et al: Comparative analysis of bleeding risk by the location and shape of arachnoid cysts: a finite element model analysis. Childs Nerv Syst. 33(1):125-134, 2017

Nikolić I et al: The association of arachnoid cysts and focal epilepsy: hospital based case control study. Clin Neurol Neurosurg. 159:3941, 2017

Chen Y et al: Treatment of middle cranial fossa arachnoid cysts: a systematic review and meta-analysis. World Neurosurg. 92:480490.e2, 2016

Hall A et al: Spontaneous subdural haemorrhage from an arachnoid cyst: a case report and literature review. Br J Neurosurg. 1-4, 2016

Rabiei K et al: Prevalence and symptoms of intracranial arachnoid cysts: a population-based study. J Neurol. 263(4):689-94, 2016

Choroid Fissure Cyst

Tubbs RS et al: Progressive symptomatic increase in the size of choroidal fissure cysts. J Neurosurg Pediatr. 10(4):306-9, 2012

Epidermoid Cyst

Ravindran K et al: Intracranial white epidermoid cyst with dystrophic calcification - a case report and literature review. J Clin Neurosci. 42:43-47, 2017

Pikis S et al: Malignant transformation of a residual cerebellopontine angle epidermoid cyst. J Clin Neurosci. 33:59-62, 2016

Dermoid Cyst

Jin H et al: Intracranial dermoid cyst rupture-related brain ischemia: case report and hemodynamic study. Medicine (Baltimore). 96(4):e5631, 2017

McArdle DJ et al: Ruptured intracranial dermoid cyst. Pract Neurol. 16(6):478-479, 2016

Neurenteric Cyst

Singh P et al: Neurenteric cyst: magnetic resonance imaging findings in an adolescent. J Pediatr Neurosci. 12(1):29-31, 2017

Chakraborty S et al: Supratentorial neurenteric cysts: case series and review of pathology, imaging, and clinical management. World Neurosurg. 85:143-52, 2016

Chen CT et al: Neurenteric cyst or neuroendodermal cyst? Immunohistochemical study and pathogenesis. World Neurosurg. 96:85-90, 2016

Prasad GL et al: Ventral foramen magnum neurenteric cysts: a case series and review of literature. Neurosurg Rev. 39(4):535-44, 2016

Preece MT, Osborn AG, Chin SS, Smirniotopoulos JG. Intracranial neurenteric cysts: imaging and pathology spectrum. AJNR Am J Neuroradiol. 27(6):1211-6, 2006.

Nonneoplastic Cysts

901

Pineal Cyst

Evans RW: Incidental findings and normal anatomical variants on MRI of the brain in adults for primary headaches. Headache. 57(5):780-791, 2017

Májovský M et al: Conservative and surgical treatment of patients with pineal cysts: a prospective case series of 110 patients. World Neurosurg. ePub, 2017

Starke RM et al: Pineal cysts and other pineal region malignancies: determining factors predictive of hydrocephalus and malignancy. J Neurosurg. 1-6, 2016

Parenchymal Cysts

Enlarged Perivascular Spaces

Sung J et al: Linear sign in cystic brain lesions ≥5 mm: a suggestive feature of perivascular space. Eur Radiol. ePub, 2017

Bakker EN et al: Lymphatic clearance of the brain: perivascular, paravascular and significance for neurodegenerative diseases. Cell Mol Neurobiol. 36(2):181-94, 2016

Ramirez J et al: Imaging the perivascular space as a potential biomarker of neurovascular and neurodegenerative diseases. Cell Mol Neurobiol. 36(2):289-99, 2016

Zhang X et al: Brain atrophy correlates with severe enlarged perivascular spaces in basal ganglia among lacunar stroke patients. PLoS One. 11(2):e0149593, 2016

Neuroglial Cyst

Ajtai B et al: Imaging of intracranial cysts. Continuum (Minneap

Minn). 22(5, Neuroimaging):1553-1573, 2016

Porencephalic Cyst

Abergel A et al: Expanding porencephalic cysts: prenatal imaging and differential diagnosis. Fetal Diagn Ther. 41(3):226-233, 2017

Intraventricular Cysts

Colloid Cyst

Brostigen CS et al: Surgical management of colloid cyst of the third ventricle. Acta Neurol Scand. 135(4):484-487, 2017

Hamidi H et al: CT and MRI features of pediatric-aged colloid cysts: report of two cases. Case Rep Radiol. 2017:2467085, 2017

Beaumont TL et al: Natural history of colloid cysts of the third ventricle. J Neurosurg. 1-11, 2016

Byard RW: Variable presentations of lethal colloid cysts. J Forensic Sci. 61(6):1538-1540, 2016

Cox M et al: The isodense colloid cyst: an easily overlooked cause of intermittent acute obstructive hydrocephalus. Intern Emerg Med. ePub, 2016

Ependymal Cyst

El Damaty A et al: Neuroendoscopic approach to intracranial ependymal cysts. World Neurosurg. 97:383-389, 2017

This part, devoted to toxic, metabolic, degenerative, and CSF disorders, addresses some of the most difficult and challenging issues in neuroimaging. In contrast to many other brain diseases, here the CNS effects are often secondary to systemic disorders. Patients who present acutely with encephalopathy may have unknown or undiagnosed metabolic derangements.

Metabolic disorders are relatively uncommon but important diseases in which imaging can play a key role in early diagnosis and appropriate patient management. Drug and alcohol abuse are increasing around the world, and the list of environmental toxins that can affect the CNS continues to increase. Recognizing toxic and metabolic-induced encephalopathies has become a clinical and imaging imperative. The two etiologies are often linked because many toxins induce metabolic derangements and some systemic metabolic diseases have a direct toxic effect on the brain.

With rapidly increasing numbers of aging people, the prevalence of dementia and brain degeneration is also becoming a global concern. Brain scans in elderly patients with mental status changes are now some of the most frequently requested imaging examinations.

Advanced MR techniques such as morphometric-volumetric analyses, diffusion tensor imaging, tractography, and iron content-sensitive imaging are now being used to obtain quantitative parameters that may increase diagnostic accuracy.

Because inherited and acquired toxic, metabolic, and degenerative brain disorders often affect the deep gray nuclei in a bilaterally symmetric pattern, we begin this section by considering the normal physiology, gross anatomy, and imaging of the basal ganglia and dopaminergic striatonigral system.

We then present an anatomy-based approach to the differential diagnosis of toxic, metabolic, and degenerative disorders. Shaded text boxes and representative cases illustrate this approach to—and some supplemental considerations for—imaging diagnosis.

Lastly, we briefly discuss normal age-related changes in the CNS, which lays the foundation for an imaging approach to dementia, brain degeneration, and CSF disorders.