Letters U Normal in the Axial
to the
Age-related Skeleton
Editor
Changes in Bone at MR Imaging
Zerhouni
Drs
Marrow
We thank
From:
Schick
Robert Diablo
the
122
M. Schick, MD Valley Radiology La Casa Via, Suite 120, Walnut
CA 94598
Editor:
The article
by Ricci et a! (1) in the October
1990 issue
of Radi-
ology describes the normal, age-related changes in the appearance of the bone marrow of the axial skeleton at magnetic resonance (MR) imaging. The authors describe a pattern of marked heterogeneity in the signal intensity of the marrow of the parietal bone and state that this is a normal finding in adults of all ages. Their illustration of this pattern, Figure lb. is a midline sagittal Ti-weighted image that depicts the sagittal suture rather than the parietal bone marrow. That this appearance on the midline section does not reflect parietal bone marrow composition can be readily confirmed by inspection of parasagittal or coronal MR images. Heterogeneity of parietal bone marrow in adult patients comparable to that seen in the region of the cranial sutures should not be attributed to a normal age-related process. Reference 1 . Ricci C, Cova cellular
MR
and
imaging
M, Kang fatty
bone
study.
YS, et al. marrow
Radiology
Normal
age-related
distribution
in the
1990;
patterns axial
of
skeleton:
177:83-88.
Ricci
sagittal
respond:
for his letter.
that Figure
believe Creek,
and
Dr Schick
lb could
suture
rather
that most
We would
certainly
than
probably
agree
represent
parietal
bone
a combination
with
changes marrow,
of both
Dr
due to but
we
is seen
on
that image. We fully agree that bone marrow patterns should not be evaluated with a midline image. However, in our study, we also evaluated parasagittal images, although this is not stated clearly. Our main goal was to establish the fact that marrow conversion did not occur randomly. A progression of conversion from the frontal and occipital areas toward the convexity seems to be the case. Admittedly, coronal views
would
have
been
needed
as well
to establish
that fact. Such
views, unfortunately, were not available in the majority of cases. We thus believed that a series of sagittally oriented sections would be sufficient. Our analysis was not based on review of the midline sagittal sections alone. As an example, we submit an illustration of a typical case with multiple parasagittal sections showing the pattern described (Figure). In summary, we agree with Dr Schick that midline sagittal sections may be confusing. However, we did take this into account and our analysis included parasagittal sections. We believe that the pattern of marrow conversion in the calvarium found in the study is valid. Elias
A. Zerhouni,
Department
MD
of Radiology,
of Medicine 600 North Wolfe Claudio
Ricci,
Department Strada
The
Street,
Johns
Baltimore,
Hopkins
MD
School
21205
MD
of Radiology,
di Fiume,
34149
University Trieste,
of Trieste
Italy
U Hypertrophic Pyloric Stenosis: Volumetric Measurement of Nasogastric Aspirate to Determine Imaging Modality From: Harris L. Cohen, MD Division of Diagnostic North Shore University
Ultrasound,
Department
Hospital-Cornell
of Radiology
University
Medical
College 300 Community
Drive,
Manhasset,
Jack 0. Haller, MD Department of Radiology, Health Sciences Center 450 Clarkson
Avenue,
NY 11030
State University at Brooklyn
Brooklyn,
NY
of New
York
11203
Editor:
In the December discussed
the
1990 issue use
of Radiology,
of volumetric
analysis
Finkelstein of gastric
means
et a! (1) aspirate as a with hyper-
of enabling the differentiation of patients pyloric stenosis (HPS) from patients with gastroesophageal reflux (GER) and of helping to determine whether ultrasound (US) or fluoroscopy of the upper gastrointestinal tract would best confirm the diagnosis. Aspirate of 10 mL or more was considered indicative of obstruction; aspirate of less than 10 mL was indicative of GER. We would like to corntrophic
Series of Ti-weighted parasagittal images. Relatively lower signal intensity is seen within the diploic space. Although the sagittal suture certainly contributes to the low signal intensity, the underlying decreased signal intensity was consistently seen in both the sagittal and parasagittal regions.
Volume
179
#{149} Number
3
mend
the authors
on their
work,
but
disagree
with
their
ap-
proach. Radiology
#{149} 877
to the
Age-related Skeleton
Editor
Changes in Bone at MR Imaging
Zerhouni
Drs
Marrow
We thank
From:
Schick
Robert Diablo
the
122
M. Schick, MD Valley Radiology La Casa Via, Suite 120, Walnut
CA 94598
Editor:
The article
by Ricci et a! (1) in the October
1990 issue
of Radi-
ology describes the normal, age-related changes in the appearance of the bone marrow of the axial skeleton at magnetic resonance (MR) imaging. The authors describe a pattern of marked heterogeneity in the signal intensity of the marrow of the parietal bone and state that this is a normal finding in adults of all ages. Their illustration of this pattern, Figure lb. is a midline sagittal Ti-weighted image that depicts the sagittal suture rather than the parietal bone marrow. That this appearance on the midline section does not reflect parietal bone marrow composition can be readily confirmed by inspection of parasagittal or coronal MR images. Heterogeneity of parietal bone marrow in adult patients comparable to that seen in the region of the cranial sutures should not be attributed to a normal age-related process. Reference 1 . Ricci C, Cova cellular
MR
and
imaging
M, Kang fatty
bone
study.
YS, et al. marrow
Radiology
Normal
age-related
distribution
in the
1990;
patterns axial
of
skeleton:
177:83-88.
Ricci
sagittal
respond:
for his letter.
that Figure
believe Creek,
and
Dr Schick
lb could
suture
rather
that most
We would
certainly
than
probably
agree
represent
parietal
bone
a combination
with
changes marrow,
of both
Dr
due to but
we
is seen
on
that image. We fully agree that bone marrow patterns should not be evaluated with a midline image. However, in our study, we also evaluated parasagittal images, although this is not stated clearly. Our main goal was to establish the fact that marrow conversion did not occur randomly. A progression of conversion from the frontal and occipital areas toward the convexity seems to be the case. Admittedly, coronal views
would
have
been
needed
as well
to establish
that fact. Such
views, unfortunately, were not available in the majority of cases. We thus believed that a series of sagittally oriented sections would be sufficient. Our analysis was not based on review of the midline sagittal sections alone. As an example, we submit an illustration of a typical case with multiple parasagittal sections showing the pattern described (Figure). In summary, we agree with Dr Schick that midline sagittal sections may be confusing. However, we did take this into account and our analysis included parasagittal sections. We believe that the pattern of marrow conversion in the calvarium found in the study is valid. Elias
A. Zerhouni,
Department
MD
of Radiology,
of Medicine 600 North Wolfe Claudio
Ricci,
Department Strada
The
Street,
Johns
Baltimore,
Hopkins
MD
School
21205
MD
of Radiology,
di Fiume,
34149
University Trieste,
of Trieste
Italy
U Hypertrophic Pyloric Stenosis: Volumetric Measurement of Nasogastric Aspirate to Determine Imaging Modality From: Harris L. Cohen, MD Division of Diagnostic North Shore University
Ultrasound,
Department
Hospital-Cornell
of Radiology
University
Medical
College 300 Community
Drive,
Manhasset,
Jack 0. Haller, MD Department of Radiology, Health Sciences Center 450 Clarkson
Avenue,
NY 11030
State University at Brooklyn
Brooklyn,
NY
of New
York
11203
Editor:
In the December discussed
the
1990 issue use
of Radiology,
of volumetric
analysis
Finkelstein of gastric
means
et a! (1) aspirate as a with hyper-
of enabling the differentiation of patients pyloric stenosis (HPS) from patients with gastroesophageal reflux (GER) and of helping to determine whether ultrasound (US) or fluoroscopy of the upper gastrointestinal tract would best confirm the diagnosis. Aspirate of 10 mL or more was considered indicative of obstruction; aspirate of less than 10 mL was indicative of GER. We would like to corntrophic
Series of Ti-weighted parasagittal images. Relatively lower signal intensity is seen within the diploic space. Although the sagittal suture certainly contributes to the low signal intensity, the underlying decreased signal intensity was consistently seen in both the sagittal and parasagittal regions.
Volume
179
#{149} Number
3
mend
the authors
on their
work,
but
disagree
with
their
ap-
proach. Radiology
#{149} 877
