Vol. 37, pp. 239 - Marianna Uigakukai.marianna-u.ac.jp/idaishi/www/3734/3,4-37... · Fig. 1....
Transcript of Vol. 37, pp. 239 - Marianna Uigakukai.marianna-u.ac.jp/idaishi/www/3734/3,4-37... · Fig. 1....
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Fig. 1. Detection numbers of liver cysts by ultrasonography or contrast-enhanced helical
computed tomography by Couinaud[s liver subsegmentation.
�US: detection numbers of liver cysts by ultrasonography. �CT: detection numbersof liver cysts by contrast-enhanced helical computed tomography. S: Couinaud[s liver
subsegment. S 1: caudate lobe, S 2: posterior lateral segment, S 3: anterior lateral
segment, S 4: quadrate lobe, S 5: anterior inferior segment, S 6: posterior inferior
segment, S7: posterior superior segment, S8: anterior superior segment
Fig. 2. Detection rates of liver cysts by ultrasonography or contrast-enhanced helical
computed tomography by Couinaud[s liver subsegmentation.
Contrast-enhanced helical computed tomography exhibited detection rates of about 90
� for all liver subsegments, with no remarkable blind spots observed in any
subsegment. The US detection rate was significantly lower for S1 than for S2, S3, S4,
S5, S6, and S8; significantly lower for S7 than for S2, S3, S4, S5, and S6; significantly
lower for S8 than for S2, S3, and S5; and significantly higher for S2 than for S1, S6, S
7, and S8. �US: detection rates of liver cysts by ultrasonography. �CT: detectionrates of liver cysts by contrast-enhanced helical computed tomography. S: Couinaud’s
liver subsegment. S1: caudate lobe, S2: posterior lateral segment, S3: anterior lateral
segment, S 4: quadrate lobe, S 5: anterior inferior segment, S 6: posterior inferior
segment, S7: posterior superior segment, S8: anterior superior segment
���� ���� �242
66
90.9�� S4 �60.4 �90.2�� S5 �69.2 �86.6�� S6 �56.7 �89.2�� S7 �39.9�94.6�� S8 �51.8�89.8�� �� �59.5�89.5� ������������� �������� Ryan
������� ���� 5������� US ������ S1 � S2� S3� S4� S5� S6� S8 ������ !� S7 � S2� S3� S4� S5� S6 ������ !� S8 � S2� S3� S5 ������ !� S2 �S1� S6� S7� S8 ������"#��� $%HCT �������������&'�()&#����*+,-./0123����4&#���� 5� S7� S8��� 31467 746�8� 23.6�9��:;&#��� �*+<=>3?����4&#���� 5� S6 ��� 157 67 26 6�8� 16.6�9��:;&#��� �@+ABC?D����4&#���� 5� S2� S3 ��361 67 18 6�8 5.0�9��:;&#��� S1����4&#���� 5� 42 67 33 6�78.6������ �EF����4&#���� 5� S4� S5� S8��� 57367 436�8� 7.5�9��:;&#���
� �� SOL �������G SOL ��H�IJ�� ���5 �US ���65 �$% HCT ���65 �KL��:;��� �M5���G SOL H� �570�832�927�� �GSOL �8 �192�315�354� �� �� ��� �US� �$% HCT���� �G SOL H� �61.6�89.8�� �GSOL �8 �54.2�89.0�������G SOL �NOP�QRSJT� �� ���5 �US ���65 �$% HCT ���65 �KL��:;��� �M5��NP�G SOL �82�116�136�� OP�G SOL �110�199�218� �� �� ��� �US��$% HCT�� �NP�G SOL �60.3 �85.3��OP�G SOL �50.5�91.3����� �Table 1��US���G SOL�����G SOL�UV�I
8��� 3�� �P�0.05�� :W�� OP�GSOL��NP�G SOL���� ������9 3�X�� �P�0.05��Y�� $% HCT ���� �����G SOL
��H&WZ��G SOL �NOP�[W\ 90�E]��8� ��'�()&#���
� ������^_��QR�IJ�� ���5 �US ���65 �$% HCT ���65 �KL��:;��� �M5��`abc �463�715�784�� bright liver c�98�104�131�� dP�efg�c �201�328�366� ���� ���� �US��$% HCT���`abc�58.9�91.0�� bright liver c �74.8�79.4�� dP�efg�c �54.9�89.6����� �Table 2��
Table 1. Detectability of Liver Cysts by Ultrasono-
graphy or Contrast-enhanced Helical Computed To-
mography with or without Liver SOL
Detection rates of liver cysts with malignant SOL were
significantly lower than those of liver cysts without
SOL or with benign SOL. US���: detection rates ofliver cysts by ultrasonography. CT���: detection ratesof liver cysts by contrast-enhanced helical computed
tomography. SOL: space occupying lesion. Chi-
square: P�0.05.
Table 2. Detectability of Liver Cysts by Ultrasono-
graphy or Contrast-enhanced Helical Computed To-
mography with or without Liver Parenchymal Disease
In comparison with the normal image group, the
bright liver group exhibited a significantly higher
ultrasonography detection rate. US ���: detectionrates of liver cysts by ultrasonography. CT���: detec-tion rates of liver cysts by contrast-enhanced helical
computed tomography. Chi-square: P�0.05.
hij�k��Glm�nop 243
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US���������� bright liver�������� ��������� �P�0.01�� ��HCT ���������� ��������� �P�0.01��
�� ������������ �US���� ��� HCT���� � ��� �����!���� ��"#� �359�592�644�� �"#� 93�122�140�� ����50�64�73� �$%�� ���� �US����HCT�� �� ��"#� �55.7 �91.9�� �"#��66.4�87.1�� ��� �68.5�87.7��$%� �Table 3��US ���������"#�&'(�����
������ ��������� �P�0.05���� HCT ��)�������� �*����+%��
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Couinaud �,-.��/�012��.���34� �567��$713�� �8�9:�;���<=�>?� Couinaud�,-.��>? �56����@�A 6���� HCT ��� B5�,-.�&65 90�
CD���A��� ,-.��� ��E.����+%�� US ��� S1� S7� S8 � S2� S3�
S5 ������� ��F� ��� S1� S7 ��� S2� S3� S4� S5� S6 ���5� ���� ��+%�� ��� S2 � S1� S6� S7� S8 ��������� �G+%�� @�@�+��US��E.� S1� S7� S8�HIJ� �� S1� S7�KFHIL7@���+M� ��� S2 �B,-.N�E.�34O�6�P�QR�STUV����W�+%����� S7� S8�B�� 314�N 74�$M� 23.6��� ��+%�� XC'MYZ �567QR�STU���E.�$7@��[\L7� ]��14�4PQR�STU�� US ����^%�_�`� 18 �N 5 � �27.8�� ��<J5&M�a��bc�4de[\L7�P�fg��h���W�+%�����S6 �B�� 157�N 26�$M� 16.6��� ��+%�� XC'MYZ �567P�fg��h��E.1��[\L7� @��i��hj�k;�lmf����n�o��$7��p�� ��M� qrstu��v�'Mp�� �7�wx��7�y�z{-.�h����W�+%����� S2� S3 �B 361�N 18�$M 5.0��� ��+%�� S2� S3 ������ |�}��73.1�� 69.5��~�,-.���G6���$7� |�� �J5y�z{-.�h�������J�GF� @��'My�z{-.����GF�%�@���� �7� y�z{-.������AW�L���J5�!"� y�"�����J5HIL7@��'Mp�� �7����$7� Clarke�15�� US�'7�#���� ,-.���$����6�� y�z{-.� 77.5���<J567� a���<���mm���G6��C�W���59:�;�����@��'74���� �7� 9:�;�����9:�����m|�����16��$7TGC �time gain compensation�� ���� ��� T¡u� N¢£�����'MyP �7�¤��¥� ;¦�§%�'M¨JF��©ª�«�M� ¬��O�6®����$7@��'F¯��567� a��D��W����°±�� K²�9:������K³��;¦�'M&���9:�;®�A4�������E�$7�´��7� �^J� '�uµ¶T·�¸;�&¹7
Table 3. Detectability of Liver Cysts by Ultrasono-
graphy or Contrast-enhanced Helical Computed To-
mography with De#erent Body Weight Groups
The ultrasonography detection rates of liver cysts were
significantly higher for both the low body weight
group and the high body weight group than for the
normal body weight group. US���: detection rates ofliver cysts by ultrasonography. CT���: detection ratesof liver cysts by contrast-enhanced helical computed
tomography. Normal body weight group: 18.5�BMI�25.0. Low body weight group: BMI�18.5. Highbody weight group: 25.0�BMI. Chi-square: P�0.05.
º�»¼ �()* �244
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Abstract
Definition of ultrasonographic blind areas in the liver:
A comparative investigation of the detection rates of
liver cysts in contrast helical CT and ultrasonography
Masasumi Miyazaki1, Fumio Tsujimoto2, Satoshi Koizumi1, Tomoyuki Ota3,
Gaku Igarashi4, Seiji Hatano2, Sachihiko Nobuoka2, and Takeshi Otsubo1
We compared the functions between ultrasonography �“US”� and contrast enhanced helical computedtomography �“contrast HCT”� for visualizing liver cysts, and conducted a retrospective investigation ofultrasonographic blind areas in the liver.
Of the 9,647 cases diagnosed with liver cysts using US at our hospital between September 2004 and
March 2008, we evaluated 511 cases comprising 1,281 lesions in which contrast HCT was conducted within
3 months before or after US. We defined the number of liver cysts detected by either US or contract HCT
as the denominators and defined the respective numbers of liver cysts detected by US and contrast HCT as
the numerators in order to calculate the detection rates of liver cysts. The detection rates of liver cysts by US
were compared with contrast CT according to Couinaud[s liver subsegment classification, the presence or
absence of liver space-occupying lesions �“liver SOL”� other than the liver cysts, the liver condition �caseswith normal findings, cases with bright liver, and cases suspicious of chronic liver disease�, and di#erencesdue to physique �cases were classified into a normal weight group, an underweight group, and an overweightgroup based on body mass index�.The detection rate of liver cysts by contrast HCT was approximately 90� in all hepatic subsegments.
When the detection rate of liver cysts by US was investigated for each subsegment, the rate was significantly
lower in S1 compared to S2, S3, S4, S5, S6, and S8 �P�0.05�, significantly lower in S7 compared to S2, S3,S4, S5, and S6 �P�0.05�, significantly lower in S8 compared to S2, S3, and S5 �P�0.05�, and higher in S2compared to S1, S6, S7, and S8 �P�0.05�. These results revealed that many blind areas by US occurred inS1, S7, and S8, and conversely, S2 had the fewest blind areas among all of subsegments.
Cases with a concomitant malignant tumor had a significantly lower detection rate by US compared to
cases with no concomitant malignant tumor �P�0.05�. Compared to cases with normal findings, cases withbright liver had a significantly higher detection rate by US �P�0.01�. Compared to the normal weight group,cases in the underweight group and the overweight group had significantly higher detection rates by US �P�0.05�.In order to clarify the liver blind areas by US, we evaluated a comparison with contrast HCT and
calculated the detection rates of liver cysts in each hepatic subsegment to investigate the cause of such blind
areas.
1 Division of Gastroenterological and General Surgery, St. Marianna University School of Medicine2 Department of Laboratory Medicine, St. Marianna University School of Medicine3 Department of Radiology, St. University School of Medicine4 Department of Gastroenterology and Hepatology, St. Marianna University School of Medicine
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