Assessment

Brain Imaging

• Structural brain imaging is performed using CT or MRI to identify focal and diffuse pathologies; longitudinal scans help track clinical progression.
• MRI outperforms CT for evaluating white matter disease and volumetric measurements.
• Functional brain imaging techniques like fMRI, MRS, SPECT, or PET are often utilized in research but are less common in clinical settings.

Neuropsychological Testing

• Although less frequent due to advanced brain imaging, neuropsychological tests remain valuable in assessing cognitive impairments and measuring their severity and progression.

Additional Methods

• EEG studies can be pivotal for diagnosing conditions like delirium, prion disease, non-convulsive status epilepticus, and stupor.
• CSF examination via lumbar puncture is crucial if inflammation or infection is suspected; it is also gaining traction in dementia evaluation.
• Genetic testing is integral for diagnosing specific familial disorders linked to known genes, such as Huntington's chorea.
• Brain biopsy, especially of the right frontal lobe, is a last-resort diagnostic method for unexplained cognitive impairments or suspected prion disease, balancing risks against potential diagnostic benefits.

Assessment of the Neuropsychiatric Patient

• Initial assessment of cognitive function covers amnesia, delirium, and dementia, with clouding of consciousness being a key indicator of delirium.
• If consciousness is intact, consider amnesia, dementia, or functional impairment as primary diagnostic categories.
• Amnestic syndrome is characterized by episodic memory deficits and may present in individuals with alcohol dependence.
• Functional causes, particularly depression in the elderly (which can mimic dementia), should be systematically assessed as they may masquerade as memory impairments.

History and Mental State Examination

• A comprehensive history is essential in neuropsychiatric assessment, especially when cognitive impairment limits patient self-reporting.
• Key historical elements include onset, duration, and progression of cognitive issues; acute onset often suggests delirium or underlying conditions like subdural hematoma.
• Past medical and family histories are crucial for identifying pre-existing conditions or genetic links that could contribute to cognitive dysfunction.

Physical Examination

• A thorough physical examination is necessary, focusing on the nervous system and identifying peripheral signs indicative of systemic disease or alcohol misuse.
• Specific physical signs, such as the Argyll-Robertson pupil or optic disc pallor, may provide critical diagnostic clues.

Investigations

• Investigative approach depends on findings from history, mental state, and physical examinations; a core set of cognitive and blood tests is typically included in dementia evaluations.
• In atypical or challenging cases, especially in younger patients, more extensive investigations may require consultation with neurologists, physicians, or neurosurgeons.

This quiz explores the role of structural and functional brain imaging techniques in the assessment of delirium. It highlights the advantages of MRI over CT and discusses the research applications of various imaging modalities. Test your knowledge about neuropsychological testing related to delirium.