Browse Tag: magnetic resonance imaging

Initial evaluation

SYMPTOMS AND SIGNS:

Brain tumors present in two patterns, not necessarily mutually exclusive. One consists of nonfocal symptoms of increased intracranial pressure, such as headaches, nausea, vomiting, confusion, and lethargy. The other consists of symptoms or signs of focal brain dysfunction, such as hemianopia, hemiparesis, cranial nerve palsies, or focal seizures. Such signs of focal brain dysfunction may have convincing localizing value even before an image of the brain is made by computed tomography (CT) or magnetic resonance imaging (MRI).

Some tumors that arise in neurologically “silent” areas, such as the parietal or frontal association cortices, may produce only nonfocal generalized symptoms of headache, confusion, behavioral change, or, eventually, a seizure, despite growing to a considerable size. Although the capacity to reach early diagnosis by CT or MRI has greatly reduced the numbers of patients in whom symptoms of increased intracranial pressure represent initial complaints, examples still remain, especially in association with fast-growing tumors and in children. The latter are particularly likely to have tumors in the posterior fossa that tend to obstruct spinal fluid pathways earlier than do supratentorial tumors. The tempo with which a brain tumor grows also influences the presenting symptoms. Despite the fixed space within the skull (once infantile sutures have closed), the human brain possesses a remarkable capacity to make room for a slowly growing tumor. Because of this, and even allowing for the relative rapidity of growth of aggressive brain tumors, such as glioblastomas, the patient usually appears better clinically than might be expected from the degree of abnormality seen on CT or MRI scan.

FOCAL CLINICAL MANIFESTATIONS OF BRAIN TUMORS

  • Frontal lobe
  • Generalized
    seizures
  • Focal motor
    seizures (contralateral)
  • Expressive aphasia
    (dominant side)
  • Behavioral changes
  • Dementia
  • Gait disorders,
    incontinence
  • Basal ganglia
  • Hemiparesis (contralateral)
  • Movement disorders
    rare
  • Parietal lobe
  • Receptive aphasia
    (dominant side)
  • Spatial
    disorientation (nondominant side)
  • Cortical sensory
    dysfunction (contralateral)
  • Hemianopia (contralateral)
  • Occipital lobe
  • Hemianopia (contralateral)
  • Visual disturbances
    (unformed)
  • Temporal lobe
  • Complex partial
    (psychomotor) seizures
  • Generalized
    seizures
  • Behavioral changes
  • Olfactory and
    complex visual auras
  • Corpus callosum
  • Dementia (anterior)
  • Behavioral changes
    (posterior)
  • Asymptomatic (mid)
  • Thalamus
  • Sensory loss (contralateral)
  • Behavioral changes
  • Language disorder
    (dominant side)
  • Midbrain/pineal
  • Paresis of vertical
    eye movements
  • Pupillary
    abnormalities
  • Precocious puberty
    (boys)
  • Sella/optic nerve/pituitary
  • Endocrinopathy
  • Bitemporal
    hemianopia
  • Monocular visual
    defects
  • Pons/medulla
  • Cranial nerve
    dysfunction
  • Ataxia, nystagmus
  • Weakness, sensory
    loss
  • Spasticity
  • Cerebellopontine angle
  • Deafness (ipsilateral)
  • Loss of facial
    sensation (ipsilateral)
  • Facial weakness (ipsilateral)
  • Ataxia
  • Cerebellum
  • Ataxis (ipsilateral)
  • Nystagmus