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Selective Posterior Cerebral Artery Injection of Amytal: New Method of Preoperative Memory Testing

      The carotid Amytal test (Wada test) was introduced, in 1948 by Wada, to localize speech function before temporal lobectomy in patients with medically refractory epilepsy, and it remains the standard for that purpose. The same test has also been used since 1962 to evaluate memory function; however, the adequacy of the test in this application has been viewed with increasing skepticism in recent years. Therefore, we developed an alternative to the Wada test. It consists of selective injection of Amytal into the posterior cerebral artery (PCA). This PCA Amytal test is designed to test only memory function (not language). We present several anatomic and functional reasons why this approach should be superior to the Wada test for this purpose. We also present preliminary data in support of this hypothesis. To date, we have had successful results of the PCA Amytal test in 38 of 45 patients (84%), and one major complication has occurred (2%).
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        • Penfield W
        • Flanigin H
        Surgical therapy of temporal lobe seizures.
        Arch Neurol Psychiatry. 1950; 64: 491-500
        • Penfield W
        • Baldwin M
        Temporal lobe seizures and the technic of subtotal temporal lobectomy.
        Ann Surg. 1952; 136: 625-634
        • Jack Jr, CR
        • Sharbrough FW
        • Marsh WR
        Use of MR imaging for quantitative evaluation of resection for temporal lobe epilepsy.
        Radiology. 1988; 169: 463-468
        • Feindel W
        Factors contributing to the success or failure of surgical intervention for epilepsy.
        Adv Neurol. 1975; 8: 281-298
        • Schomer DL
        Current concepts in neurology: partial epilepsy.
        N Engl J Med. 1983; 309: 536-539
        • Bengzon ARA
        • Rasmussen T
        • Gloor P
        • Dussault J
        • Stephens M
        Prognostic factors in the surgical treatment of temporal lobe epileptics.
        Neurology. 1968; 18: 717-731
        • Meyer FB
        • Marsh WR
        • Laws Jr, ER
        • Sharbrough FW
        Temporal lobectomy in children with epilepsy.
        J Neurosurg. 1986; 64: 371-376
        • Ojemann GA
        • Dodrill CB
        Verbal memory deficits after left temporal lobectomy for epilepsy.
        J Neurosurg. 1985; 62: 101-107
        • Milner B
        Disorders of learning and memory after temporal lobe lesions in man.
        Clin Neurosurg. 1972; 19: 421-446
        • Wada J
        • Rasmussen T
        Intracarotid injection of Sodium Amytal for the lateralization of cerebral speech dominance.
        J Neurosurg. 1960; 17: 266-282
        • Milner B
        • Branch C
        • Rasmussen T
        Study of short-term memory after intracarotid injection of sodium Amytal.
        Trans Am Neurol Assoc. 1962; 87: 224-226
        • Kelly PJ
        • Sharbrough FW
        • Kall BA
        • Goerss SJ
        Magnetic resonance imaging-based computer-assisted stereotactic resection of the hippocampus and amygdala in patients with temporal lobe epilepsy.
        Mayo Clin Proc. 1987; 62: 103-108
        • Loring DW
        • Meador KJ
        • Lee GP
        • Martin RC
        • Huh K
        Memory assessment during the intracarotid sodium Amytal procedure is a poor predictor of amnesia following unilateral temporal lobectomy (abstract).
        Neurology. 1988; 38: 279
        • Jack Jr, CR
        • Nichols DA
        • Sharbrough FW
        • Marsh WR
        • Petersen RC
        Selective posterior cerebral artery Amytal test for evaluating memory function before surgery for temporal lobe seizure.
        Radiology. 1988; 168: 787-793
        • Miller DL
        • Fedio P
        Whither the Wada? (editorial).
        Radiology. 1988; 168: 871-872
        • Yasargil MG
        • Teddy PJ
        • Roth P
        Selective amygdalohippocampectomy: operative anatomy and surgical technique.
        Adv Tech Stand Neurosurg. 1985; 12: 93-123
        • Ojemann GA
        Brain organization for language from the perspective of electrical stimulation mapping.
        Behav Brain Sci. 1983; 6: 189-230
        • Penfield W
        • Mathieson G
        Memory: autopsy findings and comments on the role of hippocampus in experiential recall.
        Arch Neurol. 1974; 31: 145-154
        • Penfield W
        • Milner B
        Memory deficit produced by bilateral lesions in the hippocampal zone.
        Arch Neurol Psychiatry. 1958; 79: 475-497
        • Van Hoesen GW
        The parahippocampal gyrus: new observations regarding its cortical connections in the monkey.
        Trends Neurosci. 1982; 5: 345-350
        • Van Hoesen GW
        • Pandya DN
        • Butters N
        Cortical afferents to the entorhinal cortex of the rhesus monkey.
        Science. 1972; 175: 1471-1473
        • Rosene DL
        • Van Hoesen GW
        Hippocampal efferente reach widespread areas of cerebral cortex and amygdala in the rhesus monkey.
        Science. 1977; 198: 315-317
        • Scoville WB
        • Milner B
        Loss of recent memory after bilateral hippocampal lesions.
        J Neurol Neurosurg Psychiatry. 1957; 20: 11-21
        • Milner B
        • Penfield W
        The effect of hippocampal lesions on recent memory.
        Trans Am Neurol Assoc. 1955; 80: 42-48
        • Signoret J-L
        Memory and amnesias.
        in: Mesulam M-M Principles of Behavioral Neurology. FA Davis Company, Philadelphia1985: 169-192
        • Mishkin M
        • Appenzeller T
        The anatomy of memory.
        Sci Am. June 1987; 256: 80-89
        • Sarter M
        • Markowitsch HJ
        The amygdala's role in human mnemonic processing.
        Cortex. 1985; 21: 7-24
        • Markowitsch HJ
        • Pritzel M
        The neuropathology of amnesia.
        Prog Neurobiol. 1985; 25: 189-287
        • Zola-Morgan S
        • Squire LR
        The neuroanatomy of amnesia: amygdala-hippocampus versus temporal stem.
        Science. 1982; 218: 1337-1339
        • Horel JA
        The neuroanatomy of amnesia: a critique of the hippocampal memory hypothesis.
        Brain. 1978; 101: 403-445
        • Niemeyer P
        The transventricular amygdala-hippocampectomy in temporal lobe epilepsy.
        in: Baldwin M Baily P Temporal Lobe Epilepsy. Charles C Thomas, Publisher, Springfield, Illinois1958: 461-482
        • Wieser HG
        • Yasargil MG
        Selective amygdalohippocampectomy as a surgical treatment of mesiobasal limbic epilepsy.
        Surg Neurol. 1982; 17: 445-457
        • Milner B
        Brain mechanisms suggested by studies of temporal lobes.
        in: Darley FL Brain Mechanisms Underlying Speech and Language. Grune & Stratton, New York1967: 122-145
        • Milner B
        Psychological aspects of focal epilepsy and its neurosurgical management.
        Adv Neurol. 1975; 8: 299-321
        • Milner B
        Clues to the cerebral organization of memory.
        in: Buser PA Rougeul-Buser A Cerebral Correlates of Conscious Experience. Elsevier/North-Holland Biomedical Press, Amsterdam1978: 139-153
        • Ivnik RJ
        • Sharbrough FW
        • Laws Jr, ER
        Effects of anterior temporal lobectomy on cognitive function.
        J Clin Psychol. 1987; 43: 128-137
        • Ivnik RJ
        • Sharbrough FW
        • Laws Jr, ER
        Anterior temporal lobectomy for the control of partial complex seizures: information for counseling patients.
        Mayo Clin Proc. 1988; 63: 783-793
        • Lesser RP
        • Dinner DS
        • Lüders H
        • Morris HH
        Memory for objects presented soon after intracarotid amobarbital sodium injections in patients with medically intractable complex partial seizures.
        Neurology. 1986; 36: 895-899
        • McGlone J
        Speech comprehension after unilateral injection of sodium Amytal.
        Brain Lang. 1984; 22: 150-157
        • Oxbury SM
        • Oxbury JM
        Intracarotid Amytal test in the assessment of language dominance.
        Adv Neurol. 1984; 42: 115-123
        • Silfvenius H
        • Blom S
        • Nilsson L-G
        • Christiansen S-Å
        Observations on verbal, pictorial and stereognostic memory in epileptic patient during intracarotid Amytal testing.
        Acta Neurol Scand Suppl. 1984; 99: 57-75
        • Kløve H
        • Grabow JD
        • Trites RL
        Evaluation of memory functions with intracarotid sodium Amytal.
        Trans Am Neurol Assoc. 1969; 94: 76-80
        • Stephens RB
        • Stillwell DL
        Arteries and Veins of the Human Brain. Charles C Thomas, Publisher, Springfield, Illinois1969: 10-70
        • Muller J
        • Shaw L
        Arterial vascularization of the human hippocampus. 1. Extracerebral relationships.
        Arch Neurol. 1965; 13: 45-47
        • Margolis MT
        • Newton TH
        • Hoyt WF
        The posterior cerebral artery. Section II. Gross and roentgenographic anatomy.
        in: Newton TH Potts DG Radiology of the Skull and Brain: Angiography. Vol 2. CV Mosby Company, St. Louis1974: 1551-1579 (Book 2)
        • Abbie AA
        The clinical significance of the anterior choroidal artery.
        Brain. 1933; 56: 233-246
        • Victor M
        • Angevine Jr, JB
        • Mancall EL
        • Fisher CM
        Memory loss with lesions of hippocampal formation: report of a case with some remarks on the anatomical basis of memory.
        Arch Neurol. 1961; 5: 244-263
        • DeJong RN
        • Itabashi HH
        • Olson JR
        Memory loss due to hippocampal lesions.
        Arch Neurol. 1969; 20: 339-348
        • Ross ED
        Sensory-specific and fractional disorders of recent memory in man. I. Isolated loss of visual recent memory. II. Unilateral loss of tactile recent memory.
        Arch Neurol. 1980; 37 (267–272): 193-200
        • Weintraub S
        • Mesulam M-M
        Right cerebral dominance in spatial attention.
        Arch Neurol. 1987; 44: 621-625
        • Fedio P
        • Weinberg LK
        Dysnomia and impairment of verbal memory following intracarotid injection of sodium Amytal.
        Brain Res. 1971; 31: 159-168
        • Rey A
        L'examen clinique en psychologie. Presses Universitaires de France, Paris1964
        • Taylor EM
        Psychological appraisal of children with cerebral defects. Harvard University Press, Cambridge, Massachusetts1959