Aphasia Diagnosis 

• Exclusion of other communication problems 
• Bedside and neuropsychologic testing 
• Brain imaging 

Verbal interaction can typically identify gross aphasias. However,  the clinician should try to differentiate aphasias from communication problems that stem from severe dysarthria, impaired hearing, vision (eg, when assessing reading),  or motor writing ability. 

Initially, Wernicke's aphasia may be mistaken for delirium. However, Wernicke's aphasia  is a pure language disturbance without other features of delirium (eg, fluctuating level of consciousness, hallucinations, inattention). 

Testing to identify specific deficits should include assessment of  the following: 

• Spontaneous speech: Speech is assessed for fluency, number of words spoken, ability  to initiate speech, presence of spontaneous errors, word-finding pauses, hesitations, and prosody. 
• Naming: Patients are asked to name objects. Those who have difficulty naming often use circumlocutions (eg, “what you use to tell time” for “clock”). 
• Repetition: Patients are asked to repeat grammatically complex phrases (eg, “no ifs, ands, or buts”). 
• Comprehension: Patients are asked to point to objects named by the clinician, carry out one-step and multistep  commands, and answer simple  and complex yes-or-no questions. 
• Reading and writing: Patients are asked to write spontaneously and to read aloud. Reading comprehension, spelling, and writing in response to dictation are assessed. 

Formal cognitive testing by a neuropsychologist or speech and language therapist may detect finer levels of dysfunction and assist in planning treatment and assessing potential for recovery. Various formal tests for diagnosing aphasia (eg, Boston Diagnostic Aphasia Examination, Western Aphasia Battery, Boston Naming Test, Token Test, Action Naming Test) are available. 

Brain imaging (eg, CT, MRI; with or without angiographic protocols) is required to characterize  the lesion (eg, infarct, hemorrhage, mass). Further tests are done to determine  the etiology of the lesion (eg, stroke, seizure disorder) as indicated (see Stroke (CVA): Diagnosis and see Seizure Disorders: Diagnosis ). 

Prognosis 

Recovery  is influenced by cause, size and location of lesions, extent of language impairment, and,  to a lesser degree, the age, education, and general health  of the patient. Children < 8 yr often regain language function after severe damage  to either hemisphere. After that age, most recovery occurs within the first 3 mo, but improvement continues to a variable degree up to a year.