Cerebrovascular Diseases

Introduction

Incidence of Cerebrovascular Diseases

Definition of Terms

Table 34-1 Causes of Cerebral Abnormalities from Alterations of Arteries and Veins

1. Atherosclerotic thrombosis 2. Transient ischemic attacks 3. Embolism 4. Hypertensive hemorrhage 5. Ruptured or unruptured saccular aneurysm or arteriovenous malformation 6. Arteritis   a. Meningovascular syphilis, arteritis secondary to pyogenic and tuberculous meningitis, rare infective types (typhus, schistosomiasis, malaria, mucormycosis, etc.)   b. Connective tissue diseases (polyarteritis nodosa, lupus erythematosus), necrotizing arteritis. Wegener arteritis, temporal arteritis, Takayasu disease, granulomatous or giant cell arteritis of the aorta, and giant cell granulomatous angiitis of cerebral arteries 7. Cerebral thrombophlebitis: secondary to infection of ear, paranasal sinus, face, etc.; with meningitis and subdural empyema; debilitating states, postpartum, postoperative, cardiac failure, hematologic disease (polycythemia, sickle cell disease), and of undetermined cause 8. Hematologic disorders: anticoagulants and thrombolytics, clotting factor disorders, polycythemia, sickle cell disease, thrombotic thrombocytopenic purpura, thrombocytosis, intravascular lymphoma, etc. 9. Trauma and dissection of carotid and basilar arteries 10. Amyloid angiopathy 11. Dissecting aortic aneurysm 12. Complications of arteriography 13. Neurologic migraine with persistent deficit 14. With tentorial, foramen magnum, and subfalcial herniations 15. Miscellaneous types: fibromuscular dysplasia, with local dissection of carotid, middle cerebral, or vertebrobasilar artery, x-irradiation, unexplained middle cerebral infarction in closed head injury, pressure of unruptured saccular aneurysm, complication of oral contraceptives 16. Undetermined cause in children and young adults: moyamoya disease and others Table 34-2 Cerebrovascular Diseases Characteristic of Each Age Period 1. Prenatal circulatory diseases leading to   a. Porencephaly   b. Hydranencephaly   c. Hypoxic-ischemic damage   d. Unilateral cerebral infarction 2. Perinatal and postnatal circulatory disorders resulting in   a. Cardiorespiratory failure and generalized ischemia—état marbre    b. Periventricular infarcts   c. Matrix hemorrhages and ischemic foci in premature infants   d. Hemorrhagic disease of the newborn 3. Infancy and childhood: vascular diseases associated with   a. Ischemic infarction   b. Congenital heart disease and paradoxical embolism   c. Moyamoya disease   d. Bacterial endocarditis, rheumatic fever, lupus erythematosus   e. Sickle cell anemia   f. Mitochondrial disorders (MELAS)    g. Homocystinuria and Fabry's angiokeratosis 4. Adolescence and early adult life: vascular occlusion or hemorrhage with   a. Pregnancy and puerperium   b. Estrogen-related stroke   c. Migraine   d. Vascular malformations   e. Premature atherosclerosis   f. Arteritis   g. Valvular heart disease   h. Sickle cell anemia   i. Antiphospholipid arteriopathy, plasma C-protein deficiency and other coagulopathies   j. Moyamoya, Takayasu diseases   k. Arterial dissections   l. Amyloid angiopathy 5. Middle age   a. Atherosclerotic thrombosis and embolism   b. Cardiogenic embolism   c. Primary (hypertensive) cerebral hemorrhage   d. Ruptured saccular aneurysm   e. Arterial dissection   f. Fibromuscular dysplasia 6. Late adult life   a. Atherosclerotic thrombotic occlusive disease   b. Embolic disease   c. Lacunar stroke   d. Brain hemorrhage (multiple causes)   e. Multiinfarct dementia   f. Binswanger disease The Stroke Syndrome Risk Factors for Stroke Ischemic Stroke

Pathophysiology of Cerebral Ischemia

Signs and symptoms	Structures involved
Paralysis of the contralateral face, arm, and leg	Somatic motor area for face and arm and the fibers descending from the leg area to enter the corona radiata
Sensory impairment over the contralateral face, arm, and leg (pinprick, cotton touch, vibration, position, two-point discrimination, stereognosis, tactile localization, baragnosis, cutaneographia)	Somatosensory area for face and arm and thalamoparietal projections
Motor speech disorder	Broca and adjacent motor area of the dominant hemisphere
"Central" aphasia, word deafness, anomia, jargon speech, alexia, agraphia, acalculia, finger agnosia, right–left confusion (the last four comprise the Gerstmann syndrome)	Central language area and parietooccipital cortex of the dominant hemisphere
Apractagnosia (amorphosynthesis), anosognosia, hemiasomatognosia, unilateral neglect, agnosia for the left half of external space, "dressing apraxia," "constructional apraxia," distortion of visual coordinates, inaccurate localization in the half field, impaired ability to judge distance, upside-down reading, visual illusions	Usually nondominant parietal lobe. Loss of topographic memory is usually caused by a nondominant lesion, occasionally by a dominant one
Homonymous hemianopia (often superior homonymous quadrantanopia)	Optic radiation deep to second temporal convolution
Paralysis of conjugate gaze to the opposite side	Frontal contraversive field or fibers projecting therefrom
Avoidance reaction of opposite limbs	Parietal lobe
Miscellaneous:
Ataxia of contralateral limb(s)	Parietal lobe
So-called Bruns ataxia or apraxia of gait	Frontal lobes (bilateral)
Loss or impairment of optokinetic nystagmus	Supramarginal gyrus or inferior parietal lobe
Limb-kinetic apraxia	Premotor or parietal cortical damage
Mirror movements	Precise location of responsible lesions not known
Cheyne-Stokes respiration, contralateral hyperhidrosis, mydriasis (occasionally)	Precise location of responsible lesions not known
Pure motor hemiplegia	Upper portion of the posterior limb of the internal capsule and the adjacent corona radiata

Signs and symptoms	Structures involved
Paralysis of opposite foot and leg	Motor leg area
A lesser degree of paresis of opposite arm	Involvement of arm area of cortex or fibers descending therefrom to corona radiata
Cortical sensory loss over toes, foot, and leg	Sensory area for foot and leg
Urinary incontinence	Posteromedial part of superior frontal gyrus (bilateral)
Contralateral grasp reflex, sucking reflex, gegenhalten (paratonic rigidity), "frontal tremor"	Medial surface of the posterior frontal lobe (?)
Abulia (akinetic mutism), slowness, delay, lack of spontaneity, whispering, motor inaction, reflex distraction to sights and sounds	Uncertain localization—probably superomedial lesion near subcallosum
Impairment of gait and stance (gait "apraxia")	Inferomedial frontal–striatal (?)
Mental impairment (perseveration and amnesia)	Localization unknown
Miscellaneous: dyspraxia of left limbs	Corpus callosum
Tactile aphasia in left limbs	Corpus callosum
Cerebral paraplegia	Motor leg area bilaterally (because of bilateral occlusion of anterior cerebral arteries)

Signs and symptoms	Structures involved
Central territory
Thalamic syndrome: sensory loss (all modalities), spontaneous pain and dysesthesias, choreoathetosis, intention tremor, spasms of hand, mild hemiparesis	Ventral posterolateral nucleus of thalamus in territory of thalamogeniculate artery. Involvement of the adjacent subthalamic nucleus or its pallidal connections results in hemiballismus and choreoathetosis.
Thalamoperforate syndrome: (1) superior, crossed cerebellar ataxia; (2) inferior, crossed cerebellar ataxia with ipsilateral third-nerve palsy (Claude syndrome)	Dentatothalamic tract and issuing third nerve
Weber syndrome—third-nerve palsy and contralateral hemiplegia	Issuing third nerve and cerebral peduncle
Contralateral hemiplegia	Cerebral peduncle
Paralysis or paresis of vertical eye movement, skew deviation, sluggish pupillary responses to light, slight miosis and ptosis (retraction nystagmus and "tucked-in" eyelids may be associated)	Supranuclear fibers to third nerve, high midbrain tegmentum ventral to superior colliculus (nucleus of Cajal, nucleus of Darkschevich, rostral interstitial nucleus of the medial longitudinal fasciculus, and posterior commissure)
Contralateral ataxic or postural tremor	Dentatothalamic tract (?) after decussation. Precise site of lesion unknown.
Decerebrate attacks	Damage to motor tracts between red and vestibular nuclei
Peripheral territory
Homonymous hemianopia	Calcarine cortex or optic radiation; hemiachromatopsia may be present. Macular or central vision is preserved if posterior striate area is spared.
Bilateral homonymous hemianopia, cortical blindness, unawareness or denial of blindness; achromatopsia, failure to see to-and-fro movements, inability to perceive objects not centrally located, apraxia of ocular movements, inability to count or enumerate objects	Bilateral occipital lobe, possibly with involvement of parietooccipital region
Dyslexia without agraphia, color anomia	Dominant calcarine lesion and posterior part of corpus callosum
Memory defect	Lesion of inferomedial portions of temporal lobe bilaterally; occasionally of the dominant side only
Topographic disorientation and prosopagnosia	Nondominant calcarine and lingual gyri, usually bilateral
Simultagnosia	Dominant visual cortex, sometimes bilateral
Unformed visual hallucinations, metamorphopsia, teleopsia, illusory visual spread, palinopsia, distortion of outlines, photophobia	Calcarine cortex