336
Age-Matched Normal Values and Topographic Maps
for Regional Cerebral Blood Flow Measurements
by Xe-133 Inhalation
HIROSHI M A T S U D A , M . D . , * TOSHIO M A E D A , M . D . , * MASATO Y A M A D A ,
R.T.,t
Luo Xi Gui, M . D . , * NORIHISA TONAMI, M . D . , * AND KINICHI HISADA, M . D . *
Downloaded from http://stroke.ahajournals.org/ by guest on June 17, 2017
SUMMARY The relationship between normal aging and regional cerebral blood flow (rCBF) computed
as initial slope index (ISI) by Fourier method was investigated in 105 right-handed healthy volunteers (132
measurements) by Xe-133 inhalation method, and age-matched normal values were calculated. Mean brain
ISI values showed significant negative correlation with advancing age (r = —0.70, p < 0.001), and the
regression line and its 95% confidence interval was Y = - 0 . 3 2 (X-19) + 63.5 ± 11.2 (19 § x g 80).
Regional ISI values also showed significant negative correlations for the entire brain (p < 0.001). The
regional reductions of ISI values with advancing age were significantly greater in the regional distribution of
the middle cerebral arteries bilaterally, compared with regions in the distribution of the other arteries (p <
0.05). Therefore, measured rCBF values for patients must be compared to age-matched normal values for
mean hemispheric and each region examined. Two kinds of topographic maps, brain map showing rCBF
compared to age-matched normal values and showing hemispheric differences were made by dividing
patient's values by the 95% confidence limits for age-matched normal values and displaying laterally index
calculated as follows, respectively.
Laterality index = 100 (1 +
(Right)flow + (Left)flow
These maps were useful for evaluating significantly decreased or increased regions and regional hemispheric
differences.
Stroke Vol 15, No 2, 1984
SINCE CEREBRAL BLOOD FLOW (CBF) measurements in man were reported by Kety and Schmidt in
1945,' influences of aging on CBF has often been a
subject of controversy. Kety and others mentioned that
there were progressive reductions of CBF with aging in
normal subjects free from clinical evidence of hypertension or arteriosclerosis.2"3 By contrast, Shenkin and
others said that there were no reductions of CBF associated with aging unless accompanied by hypertension, arteriosclerosis and dementia.6"8 In these reports,
however, such invasive methods as nitrous oxide and
Kr-85 inhalation, or Xe-133 intra-carotid injection
were used for measurements of CBF. Therefore, subjects were limited mainly to hospitalized patients and it
was hard to say whether or not the measurements were
carried out in the resting state. While, Xe-133 inhalation method for measuring regional cerebral blood
flow (rCBF) is noninvasive, it also offers the opportunity to simultaneously study both hemispheres and the
entire brain. Therefore, this method is more suitable
for investigation of relations between normal aging
and rCBF. The present study was designed to investigate these relationships by measuring age-matched
normal rCBF values and defining brain maps which
would allow comparison of patient's values with these
regional values measured by Xe-133 inhalation method.
From the Department of Nuclear Medicine, School of Medicine,
Kanazawa University, Kanazawa,* and the Division of Centra] Isotope
Service, Kanazawa University Hospital, Kanazawat.
Address correspondence to: Hiroshi Matsuda, M.D., Department of
Nuclear Medicine, School of Medicine, Kanazawa University, 13-1
Takara-machi, Kanazawa-City, Ishikawa 920, Japan.
Received March 3, 1983; revision 1 accepted August 31, 1983.
Materials and Methods
One hundred and thirty two measurements of rCBF
were performed in 105 right-handed (judged by Edinburgh handedness questionnaire 9 ' l0 healthy volunteers
free from cardiovascular and pulmonary diseases and
risk factors of atherothrombotic stroke including hypertension, diabetes mellitus and hyperlipidemia."
There were 57 males and 48 females, aged 19 to 80
years old (mean 42 years) (table 1). The old age group
above 60 was subjected to psychometrical testing (Hasegawa scale12) and diagnosed normal. Hematocrit was
determined in all subjects.
The measurements were carried out in a room where
the ambient noise level was 61 db (A) derived from
inhalation system and blowers and illumination intensity was 3 lux at rest and in the eye closed state. Xe133 inhalation system (Meditronic Novo Diagnostic
Systems, Inhalation Cerebrograph, Denmark) consists
of 32 scintillation detectors placed in parallel. One pair
of the detectors was mounted in a position over the
brain stem and cerebellar region (fig. 1).
The data were analyzed by Fourier method,13"13 and
initial slope index (ISI, computed on the period 30 to
90 seconds from the beginning of inhalation)13"16 was
used in this presentation as the index of rCBF. The
relation between age and regional hemispheric percent
values, which are obtained by dividing the regional
values by hemispheric mean values, was also studied.
Besides, two kinds of topographic maps, brain map
showing rCBF compared to age-matched normal values and showing hemispheric differences were made
for the purpose of evaluating significantly decreased or
increased regions and regional hemispheric differences, respectively. These maps were made by divid-
AGE-MATCHED NORMAL VALUES AND TOPOGRAPHIC MAPS/Matsuda et al
TABLE 1 Age Distribution of Healthy Volunteers
Number of volunteers (measurements)
Females
Total
Males
Age
19-30
31^0
41-50
51-60
61-70
71-80
Total
30(40)
9(14)
5(9)
5(6)
4(4)
4(4)
57(77)
8(8)
5(5)
11(16)
10(12)
12(12)
2(3)
48(55)
38(48)
14(19)
16(24)
15(18)
16(16)
6(7)
105(132)
ing patient's values by the 95% confidence limits for
age-matched normal values and displaying laterality
index calculated as follows.
Downloaded from http://stroke.ahajournals.org/ by guest on June 17, 2017
Laterality index =
(Right)flow - (Left)flow
100 (1 +
(Right)flow + (Left)flow'
The values of laterality index more and less than 100
denote the dominancies of the right and left hemisphere, respectively.
End expired air PCO2 (PECO 2 , calculated as follows)17 was recorded from the face mask during the
measurements along with the mean arterial blood pressure (MABP). PECO2 = (Barometric pressure - 47)
mmHg x %CO2. ISI values were not corrected for
changes in PECO2.
Results
PECO2 and MABP were 37.8 ± 2.9 and 83.7 ±
12.0 mmHg (mean ± 1 standard deviation (s.d.)) respectively, and didn't significantly correlate with aging (r = 0.03 and r = 0.18, respectively, p > 0.05).
Mean brain ISI values showed significant negative correlations with advancing age (r = —0.70:total, r =
-0.72:males, r = -0.61:females, p < 0.001), and
the regression lines were Y = - 0 . 3 2 ( X - 1 9 ) + 63.5
(total), Y = - 0.37 ( X - 1 9 ) + 64.1 (males) and Y =
- 0 . 2 6 ( X - 19) + 62.5 (females) (19 ^ x g 80).
The number of subjects was so large that the 95%
confidence interval of the regressjoj) line (total) was
able to approximate to ± 1.96 VVE = ±11.2 (VE:
mean residual square) (fig. 2). There were no significant differences in the correlation coefficients between
males and females (p > 0.05). Regional ISI values
also showed significant negative correlations with advancing age for the entire brain (p < 0.001) (fig. 3).
Regional regression lines and their 95% confidence
intervals were also calculated (fig. 4). There were no
significant differences in the correlation coefficients
obtained from parallel regions between the right and
left hemispheres (p > 0.05). The regional reductions
of ISI values with advancing age were significantly
greater in the regional distribution of the middle cerebral arteries (MCA, corresponding detectors are 4, 5,
6 , 7 , 9 , 10, 11, 13, 1 5 , 2 0 , 2 1 , 2 2 , 2 3 , 2 5 , 2 6 , 2 7 , 2 9 ,
31, see fig. 3) bilaterally, compared with regions in the
distribution of the anterior cerebral (detectors, 1,3, 17
337
and 19), the posterior cerebral (detectors, 8, 12, 16,
24, 28, 32) and vertebrobasilar (detectors, 2, 18) arteries (p < 0.05). Regional hemispheric percent values
for frontal lobe (mean value of detectors, 1,3,4, 5, 6,
7, and 9, or of detectors, 17, 19, 20, 2 1 , 22, 23 and 25)
were greater than that of either parietal (mean value of
7,9, 11, B a n d 15, or 23, 25, 27, 29 and31), temporal
(mean value of 6, 8, 10, 12 and 14, or 22, 24, 26, 28
and 30), occipital lobe (mean value of 14, 15 and 16,
or 30, 31 and 32), or brain stem and cerebellar region
(2 or 18) for the entire age (fig. 5). But, this hyperfrontal distribution became gradually lost with advancing
age, because reductions of ISI values with aging were
greater in the frontal lobe than in other regions.
Topographic patterns of rCBF as a brain-map, were
made on a 64-year-old patient who suffered from left
angular artery infarction after 102 days from the onset
(fig. 6a) by dividing patient values with the lower 95%
confidence limits for the age-matched normal values
(fig. 6b, c, d). According to this map, it became clear
that rCBF of extensive regions except for part of frontoparietal and brain stem and cerebellar regions fell
within the lower normal limits or showed significant
decreases for the left hemisphere (p < 0.05), while all
regions were within normal limits for the right hemisphere.
There were no significant differences in the hemispheric mean ISI values between the right and left
hemispheres (p > 0.05), on the other hand significant
regional hemispheric differences were observed in superior frontal (right dominancy) and posterior inferior
temporal (left dominancy) regions for these normal
right-handed subjects (Student's Mest, p < 0.05).
Mean and 1 s.d. values for laterality indices of hemispheric mean values were 100.3 ± 1.2 (fig. 7). Mean
values for regional laterality indices were less than 100
(left dominancy) between the pairs of detectors at positions (see fig. 1)7 and 23, 8 and 24, 10 and 26, 12 and
28, and 13 and 29, on the other hand more than 100
(right dominancy) between the other pair detectors,
while 1 s.d. values for regional laterality indices were
below 3 in all regions. In the patient mentioned above,
FIGURE 1. Location of 16 detectors over the right hemisphere. Left hemisphere was identically covered by an additional 16.
STROKE
338
regional laterality indices showed significantly greater
values (p < 0.05), that is the right hemisphere was
dominant, in all regions except for part of frontal and
temporal lobes (fig. 8).
VOL
15, No 2, MARCH-APRIL
1984
ed to have the following three advantages in comparison with the conventional Obrist method. IJ~" [1] In
Obrist method, delayed start fit time has been used to
avoid the artifacts from the air passages. The main
disadvantage of this method is the omission of the first
part of the clearance curve which contains information
about the flow of the fast clearing gray matter. By
contrast, Fourier method provides complete informa-
Discussion
In analyzing head clearance curves by the Xe-133
inhalation technique, Fourier method has been report-
FOURIER ISI
8Or
70-
Downloaded from http://stroke.ahajournals.org/ by guest on June 17, 2017
FIGURE 2. Correlation of mean brain ISI
measured by Fourier method with age in 105
right-handed healthy volunteers. ISI values
showed significant negative correlation with
advancing age (r = -0.70, p < 0.001). The
regression line and its 95% confidence interval
was Y = -0.32X + 63.5 ± 11.2 (19 § x
=§ 80). Limits of confidence were showed for
regression line (—•—) andfor the 95% limits f
) of ISI value for a given age.
60-.
50-
40f"
ru-0.70
""- —
p<0.001
Nm132
Yu-O.32(X-10)+63.5*11.2
30-
20
30
40
50
60
70
80
AGE
FIGURE 3. Correlation of regional ISI values
with age. Regional ISI values showed significant negative correlations with advancing age
for the entire brain (p < 0.001). In the right
hemisphere, region of detector 4 indicated significant greater correlation than regions of detectors!, 3, 12, 13, 15, 16 and 7 greater than
2, 3, 13, 15, 16. In the left hemisphere, regions
of detectors 17, 20-23, 25-27, 30 indicated
significant greater correlations than region of
detector 18, and 20, 23 greater than 24 (p <
0.05). There were no significant differences in
the correrlation coefficients obtained from
parallel regions between the right and left
hemispheres (p > 0.05).
FIGURE 4. Regional regression lines and
their 95% confidence intervals. The 95% confidence limits (Y) of ISI values for a given age
(X) can be calculated by the equation ofY =
A(X-I9)
+ B ± C (19 S x § 80).
A:Regresslon Coefficient
B:lnterc9pt
C:9S% Confidence Interval
AGE-MATCHED NORMAL VALUES AND TOPOGRAPHIC MAPS/Matsuda et al
regional hemispheric
percent values
1iO%r
100%
90%
Downloaded from http://stroke.ahajournals.org/ by guest on June 17, 2017
20
40
60
80yrs
AGE
FIGURE 5. Relation between regional hemispheric percent
values and age. In each right (
) and left (
)
hemisphere, regional hemispheric percent values for frontal
lobe (•) were greater than that of either parietal (•), temporal
(O), occipital lobe (A), or brain stem and cerebellar region Aj
for the entire age. This hyperfrontal distribution became gradually lost with advancing age.
tion of the fast flow which is crucially important in
studies of the activated cortex, since it is a total curve
analysis from the beginning of inhalation. [2] Correction for recirculation is more accurate owing to immunity from lung-to-brain delay between the monitored
end-tidal value for air curve and the head curves. [3]
The method has a faster computation time. We compared the reproducibilities of flow parameters, F, and
ISI between Fourier and Obrist methods by back-toback measurements.18 The coefficient variations
(C.V.) of the change from first to second measurement
were 5.1%, 3.3%, 6.4%, 3.4% for hemispheric mean
values, 9.1%, 5.0%, 13.0%, 6.6% on average for regional absolute values, and 7.9%, 3.9%, 12.2%, 5.5 %
on average for regional hemispheric percent values in
F, by Fourier method, ISI by Fourier method, F, by
Obrist method and ISI by Obrist method, respectively.
ISI by Fourier method showed the best reproducibility
and the values for C.V. were almost equal to the results
obtained by intra-carotid injection method.19"21 ISI by
Fourier method was considered to be an excellent index of rCBF as Risberg et al. and Prohovnik et al. have
reported previously.' 4 -"
ISI values were not corrected for changes in PECO 2 .
Blauenstein et al. reported that PECO2 was not a main
determinant of the biological variations of rCBF under
rest conditions.22 For almost the same reason, Melamed et al. also did not correct for PECO2 changes.23
Moreover, there were no significant differences in the
PECO2 levels among normal subjects in the present
study.
339
Naritomi et al24 and Davis et al" reported significant negative correlations (r = - 0 . 7 0 and —0.69)
between aging and mean brain F, values by Obrist
method in 46 and 53 normal subjects, respectively.
Melamed et al. also reported significant negative correlations (r = — 0.46) between age and mean brain ISI
values by Obrist method in 44 normal subjects.23 In the
present study, significant negative correlation (r =
— 0.70) were obtained between age and mean brain ISI
values using the Fourier method in 105 normal subjects. Regional reductions were significantly greater in
the regional distribution of the MCA than in the distribution of other arteries, bilaterally. This greater reduction in the MCA territory was also pointed out by
Naritomi et al. and Melamed et al. 2324
As for the differences in mean brain flow between
the male and female groups, Davis et al. reported that
mean flow for the female group below age 50 was
higher than the mean male flow and that the mean
flows for both groups were similar above age 50. M
There were no significant differences in the correlation
coefficients of the mean brain ISI values with aging
between male and female groups in the present study,
although the mean age for the male group (36 years)
was 14 years less than that for the female group (50
years). Further investigation should be continued on
this point.
As factors for progressive reductions of rCBF with
advancing age, firstly, there is a loss of brain substance
and hence decreased cerebral metabolism. In pathological findings of normal brains established to be free
of disease by careful neurological examination shortly
before death, it has been reported that populations of
cerebral cortical neurones progressively decrease in
number with aging, especially in superior temporal
and precentral regions.26 Some brains showed softening and changes of senile type (senile plaques, Alzheimer's neurofibrillary change and granulovacuolar
degeneration) either alone or in combination.27 A gradual increase in ventricular size with advancing age in
X-ray CT findings also indicates progressive reduction
of brain parenchyma.28-29 These changes of brain parenchyma correlate well with reductions of cerebral
blood flow and metabolism. 2 7 3 0 Secondly, atherosclerotic changes may be considered. In autopsy studies of the patients dying without morphologic evidence
of atherosclerotic disease, it has been reported that the
MCA and basilar arteries had the most atherosclerosis,
which caused vascular narrowing and increased resistance.31-32
In resting wakeness, cerebral gray matter flow is
reported to show a hyperfrontal distribution.19-23-33-34
Ingvar reported that the hyperfrontal distribution of
gray matter flow suggested the activity of the brain
with an anticipatory "stimulation of behavior". 33
Though these high frontal flow values were seen in all
age groups in the present study, it was gradually reduced with advancing age so that only small differences were noted compared to the other regions in old
age.
340
STROKE
VOL 15, No 2, MARCH-APRIL
It is concluded that measured rCBF values for patients with disease must be compared to age-matched
normal values for mean hemispheric and each region
examined, because rCBF inhomogeneously becomes
reduced with advancing age. The brain map showing
rCBF compared to age-matched normal values is useful for evaluating significantly decreased or increased
regions.
Regarding hemispheric differences for CBF in normal subjects, opinions vary. Ingvar said that there
were no significant hemispheric differences in hemi4 10
3 FEE
Downloaded from http://stroke.ahajournals.org/ by guest on June 17, 2017
KANAZAWA.UN IV
- 0 3B
H
HOSPITAL
44
38
ion
M
28
1984
AGE-MATCHED NORMAL VALUES AND TOPOGRAPHIC MAPS/Matsuda et al
341
FIGURE 7. Mean and 1 s.d. values for hemispheric mean and regional laterality indices in
right-handed healthy volunteers. Laterality index is calculated as follows: Laterality index
= iooa
The
(Right)flow + (Left)flow
values of the index more and less than 100
denote the dommancies of the right and left
hemisphere, respectively.
100.30.2
Downloaded from http://stroke.ahajournals.org/ by guest on June 17, 2017
107'
8
12
spheric mean values," while Carmon et al reported
that blood volume was higher in the right hemisphere
of the right-handed and in the left hemisphere of the
left-handed.35 Concerning regional hemispheric differences, Blauenstein et al reported that rCBF in the inferior frontal region was higher in the right hemisphere
of the right-handed,22 while Prohovnik et al reported
that rCBF in the superior frontal and posterior temporal
regions were higher in the right hemisphere, and rCBF
in the inferior temporal region higher in the left hemisphere of the right-handed.34 In our normal right-handed subjects, there were no significant differences between the right and left hemispheric mean values,
though the mean value of laterality indices was slightly
above 100. The result of regional hemispheric differences was similar to that of Prohovnik et al.34 Laterality index is stable regardless of the values of rCBF,
moreover significant abnormal values were obtained in
a study of our patients with cerebral infarction.
FIGURE 8. Brain maps of patient in Fig. 6. The image is
displayed as either clock symbols in the circles (90° = 25,
above) or shaded squares including the regional indices
(below). Stars in hemispheric mean and the circles denote the
significance of the indices compared to normal values (p <
0.05). Regional laterality indices show significantly greater
values, tliat is the right hemisphere is dominant, in all regions
except for part offrontal and temporal lobes.
FIGURE 6. Topographic map for rCBF was made by dividing the rCBF values for this 64-year-old patient with left angular
artery infarction by the lower 95% confidence limits for age-matched normal values. Right and left hemispheric mean values of
the patient were 117% and 101% of the lower limits, respectively. Topographic map showed regional percentages above or
below the lower limits using the clock symbols in the circles (90° = 25%). In the left hemisphere, all regions except for part of
frontoparietal and brain stem and cerebellar regions fell within the lower normal limits or showed significant decreases (p <
0.05).
a. X-ray CT of the patient. Low density area was observed in left parieto-occipital region.
b. rCBF of the patient.
c. The lower 95% confidence limits of age-matched normal values.
d. Regional brain map showing flow reductions compared to age-matched normal values.
STROKE
342
References
Downloaded from http://stroke.ahajournals.org/ by guest on June 17, 2017
1. Kety SS, Schmidt CF: The determination of cerebral blood flow in
man by the use of nitrous oxide in low concentrations. Am J
Physiol 143: 53-66, 1945
2. Kety SS: Human cerebral blood flow and oxygen consumption as
related to aging. J Chronic Dis 3: 478-486, 1956
3. Sheinberg P, Blackburn I, Rich M, Saslaw M: Effects of aging on
cerebral circulation and metabolism. Arch Neural Psychiatry 70:
77-85, 1953
4 Fazekas JF, Kleh J, Finnerty FA: Influence of age and vascular
disease on cerebral hemodynamics and metabolism. Am J Med 18:
477-485, 1955
5. Dekoninck WJ, Calay R, Hongne JC: CBF in elderly with chronic
cerebral involvement. In Ingvar DH, Lassen NA (eds): Cerebral
Function, Metabolism and Circulation. Acta Neurol Scand 56:
412-413, 1977
6. Shenkin HA, Novak P, Goluboff B et al. The effects of aging,
arteriosclerosis, and hypertension upon the cerebral circulation. J
Clin Invest 32: 459-^65, 1953
7. Lassen NA, Feinberg I, Lane MH: Bilateral studies of cerebral
oxygen uptake in young and aged normal subjects and in patients
with organic dementia. J Clin Invest 39: 491-500, I960
8. Olesen J: Cerebral blood flow. Methods for measurement, regulation, effects of drugs and changes in disease Acta Neurol Scand 50
(suppl 57): 1-134, 1974
9. Oldfield RC: The assessment and analysis of handedness: the Edinburgh inventory. Neuropsychologia 9: 97-113, 1971
10. Raczkowski D, Kalat JW: Reliability and validity of some handedness questionnaire items. Neuropsychologia 12: 43-47, 1974
11. Kannel WB, Blaisdell FW, Gifford R, et al: Risk factors in stroke
due to cerebral infarction: A statement for physicians prepared by a
subcommittee and approved by the executive committee of the
council on cerebrovascular disease of the American Heart Association. Stroke 2: 423-^128, 1971
12. Hasegawa K: An investigation of dementia rating scale for the
elderly. Jpn Clin Psychiatry 16: 965-969, 1974
13. Jablonski T, Prohovnik I, Risberg J, StShl KE, Maximillian VA,
Sabsay E: Fourier analysis of Xe-133 inhalation curves: accuracy
and sensitivity. Acta Neurol Scand 60: 216-217, 1979
14. Prohovnik 1: Mapping bramwork: theoretical and methodological
considerations in applying the regional cerebral blood flow method
to neuropsychology (Gleerup, Lund 1980)
15. Risberg J, Prohovnik I: rCBF measurements by Xe-133 inhalation:
recent methodological advances. In Juge O, Donath A (eds): Prog
Nucl Med 7. Baltimore, Karger Basel and Univ Park Press, pp. 7081, 1981
16. Risberg J, AH Z, Wilson EM, Wills EL, Halsey JH: Regional
cerebral blood flow by Xe-133 inhalation. Stroke 6: 142-147, 1975
17. Deshmukh VD, Meyer JS: The Baylor System. In Deshmukh VD,
Meyer JS (eds): Noninvasive measurement of regional cerebral
blood flow in man. New York/ London, Spectrum Publications,
pp. 106, 1978
18. Matsuda H, Maeda T, Luo Xi Gui, Yamada M, Hisada K. Repro-
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
VOL 15, No 2, MARCH-APRIL
1984
ducibility determined by serial measurements of regional cerebral
blood flow by Xe-133 inhalation: Comparison between Fourier and
Obnst analysis. Jpn J Nucl Med (Kakuigaku) 19: 951-957, 1982
Wilkinson IMS, Bull JWD, DuBoulay GH, Marshall J, Russel
RWR, Symon L: Regional blood flow in the normal cerebral hemisphere. J Neurol Neurosurg Psychiat 32: 367-378, 1969
McHenry LC, Jaffe ME, Goldberg HI: Regional cerebral blood
flow measurement with small probes: I. Evaluation of the method.
Neurology 19: 1198-1206, 1969
Ingvar DH, Cronqvist S, Ekberg R, Risberg J, H0edt-Rasmussen
K: Normal values of regional cerebral blood flow and weight estimates of gray and white matter: in regional cerebral blood flow
(rCBF). Acta Neurol Scand (suppl) 14: 72-78, 1965
Blauenstein UW, Halsey JH, Wilson EM, Willis EL, Risberg J.
Xe-133 inhalation method: analysis of reproducibility: some of its
physiological implications. Stroke 8: 92-102, 1977
Melamed E, Lavy S, Bentin S, Cooper G, Rinot Y: Reduction in
regional cerebral blood flow during normal aging in man. Stroke
11: 31-35, 1980
Naritomi H, Meyer JS, Sakai F, Yamaguchi F, Shaw T: Effects of
advancing age on regional cerebral blood flow. Arch Neurol 36:
410-416, 1979
Davis SM, Ackerman RH, Correia JA, et al: Cerebral blood flow
and reactivity in stroke-age normal controls. J Cereb Blood Flow
Metabol 1 (suppl I): S547-S548, 1981
Brody H: Organization of the cerebral cortex III: A study of aging
in the human cerebral cortex. J Comp Neurol 102: 511-516, 1955
Thomlinson BE, Blessed G, Roth M Observations on the brains of
nondemented old people. J Neurol Sci 7: 331-356, 1968
Barron SA, Jacobs L, Kinkel WR: Changes in size of normal lateral
ventricles during aging determined by computerized tomography
Neurology (Minneap) 26: 1011-1013, 1976
Roberts MA, Caird Fl: Computerized tomography and intellectual
impairment in the elderly. J Neurol Neurosurg Psychiatry 39: 986989, 1976
Lassen NA: Cerebral blood flow and oxygen consumption in man.
Physiol Rev 39: 183-238, 1959
Blumenthal HT, Handler FP, Bache JO. The histogenesis of arteriosclerosis of the large cerebral arteries: with an analysis of the
importance of mechanical factors. Am J Med 17: 337-347, 1954
Robert JC, Moses C, Wilkins RH: Autopsy studies in atherosclerosis: I. Distribution and severity of atherosclerosis in patients during
without morphologic evidence of atherosclerotic catastrophic Circ
20: 511-519, 1959
Ingvar DH: 'Hyperfrontal' distribution of the cerebral gray matter
flow in resting wakefulness: on the functional anatomy of the
conscious state. Acta Neurol Scand 60: 12-35, 1979
Prohovnik I, Hikansson K, Risberg J: Observations on the functional significance of regional cerebral blood flow in 'Resting'
normal subjects. Neuropsychologia 18: 203-217, 1980
Carmon A, Harishanu Y, Lowinger E, Lavy SA: Assymmetries in
hemispheric blood volume and cerebral dominance. Behav Biol 7:
853-859, 1972
Age-matched normal values and topographic maps for regional cerebral blood flow
measurements by Xe-133 inhalation.
H Matsuda, T Maeda, M Yamada, L X Gui, N Tonami and K Hisada
Stroke. 1984;15:336-342
doi: 10.1161/01.STR.15.2.336
Downloaded from http://stroke.ahajournals.org/ by guest on June 17, 2017
Stroke is published by the American Heart Association, 7272 Greenville Avenue, Dallas, TX 75231
Copyright © 1984 American Heart Association, Inc. All rights reserved.
Print ISSN: 0039-2499. Online ISSN: 1524-4628
The online version of this article, along with updated information and services, is located on the
World Wide Web at:
http://stroke.ahajournals.org/content/15/2/336
Permissions: Requests for permissions to reproduce figures, tables, or portions of articles originally published in
Stroke can be obtained via RightsLink, a service of the Copyright Clearance Center, not the Editorial Office.
Once the online version of the published article for which permission is being requested is located, click Request
Permissions in the middle column of the Web page under Services. Further information about this process is
available in the Permissions and Rights Question and Answer document.
Reprints: Information about reprints can be found online at:
http://www.lww.com/reprints
Subscriptions: Information about subscribing to Stroke is online at:
http://stroke.ahajournals.org//subscriptions/