trolateral preoptic nucleus of the rat. J Neurosci 18,
4705–4721, 1998.
84. Saper CB, Chou TC, Scammell TE. The sleep switch:
hypothalamic control of sleep and wakefulness. Trends
Neurosci 24, 726–731, 2001.
85. Gaus SE, Strecker RE, Tate BA, et al. Ventrolateral
preoptic nucleus contains sleep-active, galaninergic
neurons in multiple mammalian species. Neurosci-
ence 115, 285–294, 2002.
86. Sallanon M, Denoyer M, Kitahama K, et al. Long-
lasting insomnia induced by preoptic neuron lesions
and its transient reversal by muscimol injection into
the posterior hypothalamus in the cat. Neuroscience
32, 669–683, 1989.
87. Lu J, Greco MA, Shiromani P, et al. Effect of lesions
of the ventrolateral preoptic nucleus on NREM and
REM sleep. J Neurosci 20, 3820–3842, 2000.
88. Lu J, Bjorkum AA, Xu M, et al. Selective activation
of the extended ventrolateral preoptic nucleus dur-
ing rapid eye movement sleep. J Neurosci 22, 4568–
4576, 2002.
89. Hara J, Beuckmann CT, Nambu T, et al. Genetic ab-
lation of orexin neurons in mice results in narcolepsy,
hypophagia, and obesity. Neuron 30, 345–354, 2001.
90. Lydic R, Douglas CL, Baghdoyan HA. Microinjection
of neostigmine into the pontine reticular formation of
C57BL/6J mouse enhances rapid eye movement sleep
and depresses breathing. Sleep 25, 835–841, 2002.
91. Lorente de No R. Cerebral cortex: architecture,
intracortical connections, motor projections. In: JF
Fulton, ed. Physiology of the Nervous System. New
York: Oxford University Press, pp 291–340, 1938.
92. Hubel DH, Wiesel TN. Shape and arrangement of
columns in cat’s striate cortex. J Physiol 165, 559–
568, 1963.
93. McCasland JS, Woolsey TA. High-resolution 2-
deoxyglucose mapping of functional cortical columns
in mouse barrel cortex. J Comp Neurol 278, 555–
569, 1988.
94. Gilbert CD, Wiesel TN. Columnar specificity of in-
trinsic horizontal and corticocortical connections in
cat visual cortex. J Neurosci 9, 2432–2442, 1989.
95. Hubel DH, Wiesel TN. The period of susceptibility
to the physiological effects of unilateral eye closure
in kittens. J Physiol 206, 419–436, 1970.
96. Frank MG, Issa NP, Stryker MP. Sleep enhances plas-
ticity in the developing visual cortex. Neuron 30, 275–
287, 2001.
97. Hardcastle VG. Consciousness and the neurobiology
of perceptual binding. Semin Neurol 17, 163–170,
1997.
98. Revonsuo A. Binding and the phenomenal unity of con-
sciousness. Conscious Cogn 8, 173–185, 1999.
99. Nishikawa T, Okuda J, Mizuta I, et al. Conflict of in-
tentions due to callosal disconnection. J Neurol Neuro-
surg Psychiatry 71, 462–471, 2001.
100. Alexander GE, DeLong MR, Strick PL. Parallel
organization of functionally segregated circuits linking
basal ganglia and cortex. Annu Rev Neurosci 9, 357–
381, 1986.
101. Alexander GE, Crutcher MD, DeLong MR. Basal
ganglia-thalamocortical circuits: parallel substrates for
motor,oculomotor,‘‘prefrontal’’and‘‘limbic’’functions.
Prog Brain Res 119–146, 1990.
102. Wyrtzes LM, Chatrian GE, Shaw CM, et al. Acute
failure of forebrain with sparing of brain-stem func-
tion. Electroencephalographic, multimodality evoked-
potential, and pathologic findings. Arch Neurol 46,
93–97, 1989.
103. van der Knaap MS, Smit LS, Nauta JJ, et al. Cortical
laminar abnormalities—occurrence and clinical sig-
nificance. Neuropediatrics 24, 143–148, 1993.
104. Adams JH, Graham DI, Jennett B. The neuropathol-
ogy of the vegetative state after an acute brain insult.
Brain 123, 1327–1338, 2000.
105. Caplan LR. ‘‘Top of the basilar’’ syndrome. Neurology
30, 72–79, 1980.
106. Wechler B, Dell’Isola B, Vidailhet M, et al. MRI in
31 patients with Behcet’s disease and neurological
involvement: prospective study with clinical correla-
tion. J Neurol Neurosurg Psychiatry 56, 793–798,
1993.
107. Park-Matsumoto YC, Ogawa K, Tazawa T, et al.
Mutism developing after bilateral thalamo-capsular
lesions by neuro-Behcet disease. Acta Neurol Scand
91, 297–301, 1995.
108. Kinney HC, Korein J, Panigrahy A, et al. Neuro-
pathological findings in the brain of Karen Ann
Quinlan. The role of the thalamus in the persistent
vegetative state. N Engl J Med 330 (21), 1469–1475,
1994.
109. Reeves AG, Plum F. Hyperphagia, rage, and demen-
tial accompanying a ventromedial hypothalamic neo-
plasm. Arch Neurol 20, 616–624, 1969.
110. Parvizi J, Damasio AR. Neuroanatomical correlates
of brainstem coma. Brain 126, 1524–1536, 2003.
Pathophysiology of Signs and Symptoms of Coma
37
Chapter
2
Examination of the
Comatose Patient
OVERVIEW
HISTORY
GENERAL PHYSICAL EXAMINATION
LEVEL OF CONSCIOUSNESS
ABC: AIRWAY, BREATHING,
CIRCULATION
Circulation
Respiration
PUPILLARY RESPONSES
Examine the Pupils and Their Responses
Pathophysiology of Pupillary Responses:
Peripheral Anatomy of the Pupillomotor
System
Pharmacology of the Peripheral
Pupillomotor System
Localizing Value of Abnormal Pupillary
Responses in Patients in Coma
Metabolic and Pharmacologic Causes
of Abnormal Pupillary Response
OCULOMOTOR RESPONSES
Functional Anatomy of the Peripheral
Oculomotor System
Functional Anatomy of the Central
Oculomotor System
The Ocular Motor Examination
Interpretation of Abnormal
Ocular Movements
MOTOR RESPONSES
Motor Tone
Motor Reflexes
Motor Responses
FALSE LOCALIZING SIGNS IN PATIENTS
WITH METABOLIC COMA
Respiratory Responses
Pupillary Responses
Ocular Motor Responses
Motor Responses
MAJOR LABORATORY DIAGNOSTIC AIDS
Blood and Urine Testing
Computed Tomography Imaging
and Angiography
Magnetic Resonance Imaging
and Angiography
Magnetic Resonance Spectroscopy
Neurosonography
Lumbar Puncture
Electroencephalography and
Evoked Potentials
OVERVIEW
Coma, indeed any alteration of consciousness,
is a medical emergency. The physician encoun-
tering such a patient must begin examination
and treatment simultaneously. The examina-
tion must be thorough, but brief. The examina-
tion begins by informally assessing the patient’s
level of consciousness. First, the physician ad-
dresses the patient verbally. If the patient does
38