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Anthony Marmarou, Kenneth Shulman and James LaMorgese

pressure given, only one additional point is required to establish the slope or PVI. Following a suitable control period, a volume ΔV is injected into the CSF space, raising the pressure from an initial level of P o to a peak pressure of P p ( Fig. 4 ). The PVI (ml) is then calculated by use of the relationship Following the computation of the PVI, compliance can be evaluated by Equation 1. Fig. 4. The compliance (C), pressure volume index (PVI), and outflow resistance (R o ) can be evaluated from the response of cisterna magna pressure (CMP) to a

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Grading Animals with Spinal Cord Injury November 1975 43 5 10.3171/jns.1975.43.5.0646 In Memory of Samuel R. Snodgrass November 1975 43 5 10.3171/jns.1975.43.5.0647 Mechanism of Transient Ischemia November 1975 43 5 10.3171/jns.1975.43.5.0647a Our underpinnings: a bicentennial view Paul W. McCracken November 1975 43 5 515 522 10.3171/jns.1975.43.5.0515 Compartmental analysis of compliance and outflow resistance of the cerebrospinal fluid system Anthony Marmarou Kenneth Shulman James LaMorgese November 1975 43

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Jerzy Szewczykowski, Stanislaw liwka, Adam Kunicki, Pawel Dytko and Jolanta Korsak-liwka

resistance of the cerebrospinal fluid system. J Neurosurg 43 : 523 – 534 , 1975 Marmarou A, Shulman K, LaMorgese J: Compartmental analysis of compliance and outflow resistance of the cerebrospinal fluid system. J Neurosurg 43: 523–534, 1975 10. Matakas F , v Waechter R , Knüpling R , et al : Increase in cerebral perfusion pressure by arterial hypertension in brain swelling: a mathematical model of the volume-pressure relationship. J Neurosurg 42 : 282 – 289 , 1975 Matakas F, v Waechter R, Knüpling R, et

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Elizabeth A. M. Frost

B , et al : Continuous positive pressure ventilation in acute respiratory failure. Effects on hemodynamics and lung function. N Engl J Med 283 : 1430 – 1436 , 1970 Kumar A, Falke KJ, Geffin B, et al: Continuous positive pressure ventilation in acute respiratory failure. Effects on hemodynamics and lung function. N Engl J Med 283: 1430–1436, 1970 6. Marmarou A , Shulman K , LaMorgese J : Compartmental analysis of compliance and outflow resistance of the cerebrospinal fluid system. J Neurosurg 43

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Humbert G. Sullivan, J. Douglas Miller, Donald P. Becker, Roger E. Flora and Gilbert A. Allen

in patients with mass lesions. 6, 19 An explanation for such seemingly paradoxical situations is important in the management of intracranial hypertension. A comprehensive theory relating ventricular fluid pressure to fundamental properties of the brain and its surroundings is needed. In this report we relate the pressure-volume index, 12, 14 cerebrospinal fluid (CSF) elastance, 11, 12, 14 CSF outflow resistance, and the equilibrium volume of the CSF space to the ventricular fluid pressure seen as a function of the volume of a progressively expanding epidural

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J. Douglas Miller, Donald P. Becker, John D. Ward, Humbert G. Sullivan, William E. Adams and Michael J. Rosner

push ICP sharply upward. The methods available for assessing the related parameters of ICP instability, elastic properties of the intracranial contents, CSF outflow resistance, and CSF production rate 15, 17, 23, 25 should be investigated in patients with head injury, to determine their validity and their value. We believe that much important physiological data remain to be gathered from the results of controlled perturbations of the CSF system, data of immediate relevance to the management of the severely head-injured patient. References 1. Adams

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The pressure-volume function of brain elasticity

Physiological considerations and clinical applications

Frederick H. Sklar and Ilya Elashvili

Trauma. New York: Grune and Stratton, 1976, pp 233–236 19. Marmarou A , Shulman K , LaMorgese J : Compartmental analysis of compliance and outflow resistance of the cerebrospinal fluid system. J Neurosurg 43 : 523 – 534 , 1975 Marmarou A, Shulman K, LaMorgese J: Compartmental analysis of compliance and outflow resistance of the cerebrospinal fluid system. J Neurosurg 43: 523–534, 1975 20. Masserman JH : Cerebrospinal hydrodynamics. V. Studies of the volume elasticity of the human ventriculo

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leading to sustained elevations of the ICP , in Beks JWF , Bosch DA , Brock M (eds): Intracranial Pressure III. Berlin/Heidelberg/New York : Springer-Verlag , 1976 , pp 33 – 36 Marmarou A, Shapiro K, Shulman K: Isolation of factors leading to sustained elevations of the ICP, in Beks JWF, Bosch DA, Brock M (eds): Intracranial Pressure III. Berlin/Heidelberg/New York: Springer-Verlag, 1976, pp 33–36 3. Marmarou A , Shulman K , LaMorgese J : Compartmental analysis of compliance and outflow resistance

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Anthony Marmarou, Kenneth Shulman and Roberto M. Rosende

absorption was calculated from the slopes of these curves. Experimental Methods One main objective was to test the validity of the theoretical model. First the equations describing the predicted response of pressure to known changes of CSF volume ( Fig. 2 ) were programmed onto a digital computer. Next, techniques were developed for measuring and quantifying the intracranial compliance and outflow resistance of the adult cat. These biological parameters were substituted into the computer equations. Finally, the accuracy of the model was determined by

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Clearance of edema fluid into cerebrospinal fluid

A mechanism for resolution of vasogenic brain edema

Hans J. Reulen, Matsutaira Tsuyumu, Anne Tack, Andreas R. Fenske and George R. Prioleau

48) with either a low-perfusion pressure (5.0 ± 0.5 mm Hg) or a high-perfusion pressure (19.4 ± 1.4 mm Hg). An artificial CSF was used, equilibrated with CO 2 and kept at a constant temperature of 37° C and at a pH of 7.399 ± 0.01. The perfusion volume amounted to 0.375 ml/min. The perfusion pressure was kept at the desired level by changing the outflow resistance. Samples of CSF outflow were taken every 30 minutes, and blood samples every hour for their RISA-I 131 and sucrose-C 14 determination. At the end of the experimental period, 48 hours after the cold