DOI: 10.1148/rg.254045155
Imaging of Pelvic Malignancies with In-Line FDG PET–CT: Case Examples and Common Pitfalls of FDG PET1
Naveen Subhas, MD,
Pavni V. Patel, MD,
Harpreet K. Pannu, MD,
Heather A. Jacene, MD,
Elliot K. Fishman, MD and
Richard L. Wahl, MD
1 From the Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University, 601 N Caroline St, Rm 3223, Baltimore, MD 21287-0817. Presented as an education exhibit at the 2003 RSNA Annual Meeting. Received August 3, 2004; revision requested October 25; final revision received January 21, 2005; accepted March 7. R.L.W. received honoraria from GE Medical Systems, Philips, Cardinal Health, and GSK; received grant support from GE Medical Systems; is a consultant of NMP and a consultant and stockholder of Threshold Pharmaceuticals; and holds licensed technology and patents from GSK. All other authors have no financial relationships to disclose.
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Figure 1a. Primary rectal carcinoma with lymph node metastasis. (a) FDG PET scan shows metabolically active foci in the rectum and right inguinal region. (b) CT scan shows an enlarged right inguinal lymph node (arrow) and a normal-appearing rectum. (c) PET-CT scan shows increased uptake localized to the enlarged right inguinal lymph node and rectum, findings that confirm rectal carcinoma with lymph node metastasis.
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Figure 1b. Primary rectal carcinoma with lymph node metastasis. (a) FDG PET scan shows metabolically active foci in the rectum and right inguinal region. (b) CT scan shows an enlarged right inguinal lymph node (arrow) and a normal-appearing rectum. (c) PET-CT scan shows increased uptake localized to the enlarged right inguinal lymph node and rectum, findings that confirm rectal carcinoma with lymph node metastasis.
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Figure 1c. Primary rectal carcinoma with lymph node metastasis. (a) FDG PET scan shows metabolically active foci in the rectum and right inguinal region. (b) CT scan shows an enlarged right inguinal lymph node (arrow) and a normal-appearing rectum. (c) PET-CT scan shows increased uptake localized to the enlarged right inguinal lymph node and rectum, findings that confirm rectal carcinoma with lymph node metastasis.
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Figure 2a. Advanced cervical cancer. (a) FDG PET scan shows metabolically active foci in the pelvis above the bladder (B), along the paraaortic and iliac regions, and in the left supraclavicular region. (b, c) On CT (b) and PET-CT (c) scans, the foci in a are localized to the cervix and lymph nodes (arrowheads in b), findings that confirm advanced cervical cancer. B = bladder.
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Figure 2b. Advanced cervical cancer. (a) FDG PET scan shows metabolically active foci in the pelvis above the bladder (B), along the paraaortic and iliac regions, and in the left supraclavicular region. (b, c) On CT (b) and PET-CT (c) scans, the foci in a are localized to the cervix and lymph nodes (arrowheads in b), findings that confirm advanced cervical cancer. B = bladder.
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Figure 2c. Advanced cervical cancer. (a) FDG PET scan shows metabolically active foci in the pelvis above the bladder (B), along the paraaortic and iliac regions, and in the left supraclavicular region. (b, c) On CT (b) and PET-CT (c) scans, the foci in a are localized to the cervix and lymph nodes (arrowheads in b), findings that confirm advanced cervical cancer. B = bladder.
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Figure 3a. Recurrent endometrial carcinoma after hysterectomy. B = bladder. (a) FDG PET scan demonstrates metabolically active foci in the left obturator region and in the paraaortic regions. (b) CT scan shows enlarged lymph nodes (arrowheads) that correspond to the foci in a. (c) PET-CT scan shows areas of increased uptake localized to the enlarged lymph nodes, findings that confirm metastatic disease. Normal physiologic uptake is seen in the bladder.
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Figure 3b. Recurrent endometrial carcinoma after hysterectomy. B = bladder. (a) FDG PET scan demonstrates metabolically active foci in the left obturator region and in the paraaortic regions. (b) CT scan shows enlarged lymph nodes (arrowheads) that correspond to the foci in a. (c) PET-CT scan shows areas of increased uptake localized to the enlarged lymph nodes, findings that confirm metastatic disease. Normal physiologic uptake is seen in the bladder.
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Figure 3c. Recurrent endometrial carcinoma after hysterectomy. B = bladder. (a) FDG PET scan demonstrates metabolically active foci in the left obturator region and in the paraaortic regions. (b) CT scan shows enlarged lymph nodes (arrowheads) that correspond to the foci in a. (c) PET-CT scan shows areas of increased uptake localized to the enlarged lymph nodes, findings that confirm metastatic disease. Normal physiologic uptake is seen in the bladder.
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Figure 4a. Recurrent ovarian carcinoma with peritoneal metastases. (a) FDG PET scan shows metabolically active foci in the anterior abdomen near bowel loops (arrowheads). (b) CT scan demonstrates soft-tissue implants (arrowheads) that correspond to the foci in a. (c) PET-CT scan shows areas of increased uptake localized to the soft-tissue implants (arrowheads), findings that confirm metastatic disease.
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Figure 4b. Recurrent ovarian carcinoma with peritoneal metastases. (a) FDG PET scan shows metabolically active foci in the anterior abdomen near bowel loops (arrowheads). (b) CT scan demonstrates soft-tissue implants (arrowheads) that correspond to the foci in a. (c) PET-CT scan shows areas of increased uptake localized to the soft-tissue implants (arrowheads), findings that confirm metastatic disease.
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Figure 4c. Recurrent ovarian carcinoma with peritoneal metastases. (a) FDG PET scan shows metabolically active foci in the anterior abdomen near bowel loops (arrowheads). (b) CT scan demonstrates soft-tissue implants (arrowheads) that correspond to the foci in a. (c) PET-CT scan shows areas of increased uptake localized to the soft-tissue implants (arrowheads), findings that confirm metastatic disease.
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Figure 5a. Mesenteric metastasis in a patient with lymphoma (reticulum cell sarcoma) of the right iliopsoas muscle. B = bladder, K = left kidney. (a) Coronal FDG PET scan demonstrates metabolically active foci in the right lower quadrant near bowel loops. (b) Axial FDG PET scan demonstrates metabolically active foci in the left midabdomen, also near bowel loops. (c) Coronal CT scan shows a soft-tissue-attenuation nodule in the right lower quadrant (arrowhead). The nodule is adjacent to a loop of small bowel that is enhanced with oral contrast material. (d) Axial CT scan shows nodularity (arrowhead) adjacent to the descending colon. (e, f) On coronal (e) and axial (f) PET-CT scans, the metabolically active foci are localized to the areas of interest in a–d. Normal physiologic FDG activity is seen in the inferior pole of the left kidney and the bladder on all six scans. These findings confirm that the areas of increased activity are not due to physiologic FDG uptake within bowel, but in fact represent mesenteric metastases adjacent to bowel loops.
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Figure 5b. Mesenteric metastasis in a patient with lymphoma (reticulum cell sarcoma) of the right iliopsoas muscle. B = bladder, K = left kidney. (a) Coronal FDG PET scan demonstrates metabolically active foci in the right lower quadrant near bowel loops. (b) Axial FDG PET scan demonstrates metabolically active foci in the left midabdomen, also near bowel loops. (c) Coronal CT scan shows a soft-tissue-attenuation nodule in the right lower quadrant (arrowhead). The nodule is adjacent to a loop of small bowel that is enhanced with oral contrast material. (d) Axial CT scan shows nodularity (arrowhead) adjacent to the descending colon. (e, f) On coronal (e) and axial (f) PET-CT scans, the metabolically active foci are localized to the areas of interest in a–d. Normal physiologic FDG activity is seen in the inferior pole of the left kidney and the bladder on all six scans. These findings confirm that the areas of increased activity are not due to physiologic FDG uptake within bowel, but in fact represent mesenteric metastases adjacent to bowel loops.
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Figure 5c. Mesenteric metastasis in a patient with lymphoma (reticulum cell sarcoma) of the right iliopsoas muscle. B = bladder, K = left kidney. (a) Coronal FDG PET scan demonstrates metabolically active foci in the right lower quadrant near bowel loops. (b) Axial FDG PET scan demonstrates metabolically active foci in the left midabdomen, also near bowel loops. (c) Coronal CT scan shows a soft-tissue-attenuation nodule in the right lower quadrant (arrowhead). The nodule is adjacent to a loop of small bowel that is enhanced with oral contrast material. (d) Axial CT scan shows nodularity (arrowhead) adjacent to the descending colon. (e, f) On coronal (e) and axial (f) PET-CT scans, the metabolically active foci are localized to the areas of interest in a–d. Normal physiologic FDG activity is seen in the inferior pole of the left kidney and the bladder on all six scans. These findings confirm that the areas of increased activity are not due to physiologic FDG uptake within bowel, but in fact represent mesenteric metastases adjacent to bowel loops.
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Figure 5d. Mesenteric metastasis in a patient with lymphoma (reticulum cell sarcoma) of the right iliopsoas muscle. B = bladder, K = left kidney. (a) Coronal FDG PET scan demonstrates metabolically active foci in the right lower quadrant near bowel loops. (b) Axial FDG PET scan demonstrates metabolically active foci in the left midabdomen, also near bowel loops. (c) Coronal CT scan shows a soft-tissue-attenuation nodule in the right lower quadrant (arrowhead). The nodule is adjacent to a loop of small bowel that is enhanced with oral contrast material. (d) Axial CT scan shows nodularity (arrowhead) adjacent to the descending colon. (e, f) On coronal (e) and axial (f) PET-CT scans, the metabolically active foci are localized to the areas of interest in a–d. Normal physiologic FDG activity is seen in the inferior pole of the left kidney and the bladder on all six scans. These findings confirm that the areas of increased activity are not due to physiologic FDG uptake within bowel, but in fact represent mesenteric metastases adjacent to bowel loops.
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Figure 5e. Mesenteric metastasis in a patient with lymphoma (reticulum cell sarcoma) of the right iliopsoas muscle. B = bladder, K = left kidney. (a) Coronal FDG PET scan demonstrates metabolically active foci in the right lower quadrant near bowel loops. (b) Axial FDG PET scan demonstrates metabolically active foci in the left midabdomen, also near bowel loops. (c) Coronal CT scan shows a soft-tissue-attenuation nodule in the right lower quadrant (arrowhead). The nodule is adjacent to a loop of small bowel that is enhanced with oral contrast material. (d) Axial CT scan shows nodularity (arrowhead) adjacent to the descending colon. (e, f) On coronal (e) and axial (f) PET-CT scans, the metabolically active foci are localized to the areas of interest in a–d. Normal physiologic FDG activity is seen in the inferior pole of the left kidney and the bladder on all six scans. These findings confirm that the areas of increased activity are not due to physiologic FDG uptake within bowel, but in fact represent mesenteric metastases adjacent to bowel loops.
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Figure 5f. Mesenteric metastasis in a patient with lymphoma (reticulum cell sarcoma) of the right iliopsoas muscle. B = bladder, K = left kidney. (a) Coronal FDG PET scan demonstrates metabolically active foci in the right lower quadrant near bowel loops. (b) Axial FDG PET scan demonstrates metabolically active foci in the left midabdomen, also near bowel loops. (c) Coronal CT scan shows a soft-tissue-attenuation nodule in the right lower quadrant (arrowhead). The nodule is adjacent to a loop of small bowel that is enhanced with oral contrast material. (d) Axial CT scan shows nodularity (arrowhead) adjacent to the descending colon. (e, f) On coronal (e) and axial (f) PET-CT scans, the metabolically active foci are localized to the areas of interest in a–d. Normal physiologic FDG activity is seen in the inferior pole of the left kidney and the bladder on all six scans. These findings confirm that the areas of increased activity are not due to physiologic FDG uptake within bowel, but in fact represent mesenteric metastases adjacent to bowel loops.
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Figure 6a. Physiologic FDG activity in blood vessels. R = rectum. (a) FDG PET scan shows bilateral foci of increased activity in the region of the femoral vessels (arrowheads), with greater involvement on the right side than on the left. (b) CT scan shows normal iliac vessels (arrowheads) with no pathologic process. (c) On a PET-CT scan, the foci of increased activity are localized to the iliac veins (arrows), findings that are compatible with normal physiologic FDG uptake in blood vessels. Normal physiologic activity is seen in the rectum on all three scans.
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Figure 6b. Physiologic FDG activity in blood vessels. R = rectum. (a) FDG PET scan shows bilateral foci of increased activity in the region of the femoral vessels (arrowheads), with greater involvement on the right side than on the left. (b) CT scan shows normal iliac vessels (arrowheads) with no pathologic process. (c) On a PET-CT scan, the foci of increased activity are localized to the iliac veins (arrows), findings that are compatible with normal physiologic FDG uptake in blood vessels. Normal physiologic activity is seen in the rectum on all three scans.
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Figure 6c. Physiologic FDG activity in blood vessels. R = rectum. (a) FDG PET scan shows bilateral foci of increased activity in the region of the femoral vessels (arrowheads), with greater involvement on the right side than on the left. (b) CT scan shows normal iliac vessels (arrowheads) with no pathologic process. (c) On a PET-CT scan, the foci of increased activity are localized to the iliac veins (arrows), findings that are compatible with normal physiologic FDG uptake in blood vessels. Normal physiologic activity is seen in the rectum on all three scans.
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Figure 7a. Physiologic FDG activity in bowel loops in a patient with a history of endometrial cancer. (a) FDG PET scan shows multiple foci of increased FDG activity in the right midanterior portion of the abdomen. (b) CT scan obtained at the same level demonstrates normal-appearing bowel loops containing oral contrast material. No abnormal soft-tissue nodules are seen. (c) On a PET-CT scan, the foci of increased activity are localized to bowel loops, findings that confirm normal physiologic FDG uptake (cf Figs 4, 5).
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Figure 7b. Physiologic FDG activity in bowel loops in a patient with a history of endometrial cancer. (a) FDG PET scan shows multiple foci of increased FDG activity in the right midanterior portion of the abdomen. (b) CT scan obtained at the same level demonstrates normal-appearing bowel loops containing oral contrast material. No abnormal soft-tissue nodules are seen. (c) On a PET-CT scan, the foci of increased activity are localized to bowel loops, findings that confirm normal physiologic FDG uptake (cf Figs 4, 5).
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Figure 7c. Physiologic FDG activity in bowel loops in a patient with a history of endometrial cancer. (a) FDG PET scan shows multiple foci of increased FDG activity in the right midanterior portion of the abdomen. (b) CT scan obtained at the same level demonstrates normal-appearing bowel loops containing oral contrast material. No abnormal soft-tissue nodules are seen. (c) On a PET-CT scan, the foci of increased activity are localized to bowel loops, findings that confirm normal physiologic FDG uptake (cf Figs 4, 5).
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Figure 8a. Physiologic FDG activity in the ovary and uterus in an 18-year-old woman with Hodgkin lymphoma. (a) FDG PET scan shows two foci of increased activity in the pelvis. (b) CT scan depicts a right ovarian cyst (O) and a portion of the uterus (U). (c) PET-CT scan shows two foci of increased activity localized to the right ovary and the uterus, findings that are compatible with normal physiologic FDG uptake in a functional ovarian cyst and the endometrium.
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Figure 8b. Physiologic FDG activity in the ovary and uterus in an 18-year-old woman with Hodgkin lymphoma. (a) FDG PET scan shows two foci of increased activity in the pelvis. (b) CT scan depicts a right ovarian cyst (O) and a portion of the uterus (U). (c) PET-CT scan shows two foci of increased activity localized to the right ovary and the uterus, findings that are compatible with normal physiologic FDG uptake in a functional ovarian cyst and the endometrium.
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Figure 8c. Physiologic FDG activity in the ovary and uterus in an 18-year-old woman with Hodgkin lymphoma. (a) FDG PET scan shows two foci of increased activity in the pelvis. (b) CT scan depicts a right ovarian cyst (O) and a portion of the uterus (U). (c) PET-CT scan shows two foci of increased activity localized to the right ovary and the uterus, findings that are compatible with normal physiologic FDG uptake in a functional ovarian cyst and the endometrium.
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Figure 9a. Focal retention of FDG in a ureter. (a, b) Coronal (a) and axial (b) FDG PET scans show a focus of increased activity in the right side of the retroperitoneum. The coronal scan shows normal physiologic activity in the bladder (B). (c) CT scan shows no abnormally enlarged lymph nodes or soft-tissue masses. A normal right ureter is seen (arrowhead). (d) PET-CT scan shows increased radiotracer uptake localized to the right ureter, a finding that confirms focal retention of FDG in the ureter.
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Figure 9b. Focal retention of FDG in a ureter. (a, b) Coronal (a) and axial (b) FDG PET scans show a focus of increased activity in the right side of the retroperitoneum. The coronal scan shows normal physiologic activity in the bladder (B). (c) CT scan shows no abnormally enlarged lymph nodes or soft-tissue masses. A normal right ureter is seen (arrowhead). (d) PET-CT scan shows increased radiotracer uptake localized to the right ureter, a finding that confirms focal retention of FDG in the ureter.
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Figure 9c. Focal retention of FDG in a ureter. (a, b) Coronal (a) and axial (b) FDG PET scans show a focus of increased activity in the right side of the retroperitoneum. The coronal scan shows normal physiologic activity in the bladder (B). (c) CT scan shows no abnormally enlarged lymph nodes or soft-tissue masses. A normal right ureter is seen (arrowhead). (d) PET-CT scan shows increased radiotracer uptake localized to the right ureter, a finding that confirms focal retention of FDG in the ureter.
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Figure 9d. Focal retention of FDG in a ureter. (a, b) Coronal (a) and axial (b) FDG PET scans show a focus of increased activity in the right side of the retroperitoneum. The coronal scan shows normal physiologic activity in the bladder (B). (c) CT scan shows no abnormally enlarged lymph nodes or soft-tissue masses. A normal right ureter is seen (arrowhead). (d) PET-CT scan shows increased radiotracer uptake localized to the right ureter, a finding that confirms focal retention of FDG in the ureter.
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Figure 10a. Focal retention of FDG in a bladder diverticulum. B = bladder. (a) PET scan shows increased FDG activity (arrowhead) just posterior to and to the left of the bladder. (b) CT scan demonstrates a bladder diverticulum (arrowhead). (c) PET-CT scan shows increased radiotracer activity localized to the bladder diverticulum (arrowhead), a finding that confirms focal retention of FDG in the diverticulum.
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Figure 10b. Focal retention of FDG in a bladder diverticulum. B = bladder. (a) PET scan shows increased FDG activity (arrowhead) just posterior to and to the left of the bladder. (b) CT scan demonstrates a bladder diverticulum (arrowhead). (c) PET-CT scan shows increased radiotracer activity localized to the bladder diverticulum (arrowhead), a finding that confirms focal retention of FDG in the diverticulum.
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Figure 10c. Focal retention of FDG in a bladder diverticulum. B = bladder. (a) PET scan shows increased FDG activity (arrowhead) just posterior to and to the left of the bladder. (b) CT scan demonstrates a bladder diverticulum (arrowhead). (c) PET-CT scan shows increased radiotracer activity localized to the bladder diverticulum (arrowhead), a finding that confirms focal retention of FDG in the diverticulum.
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Figure 11a. Focal retention of FDG in a pelvic kidney. B = bladder. (a) FDG PET scan shows a focus of increased activity in the left side of the pelvis (arrowhead). Arrows indicate areas of normal physiologic FDG uptake in the right ureter. Normal uptake is also seen in the bladder. (b) CT scan shows a pelvic kidney (K). (c) On a PET-CT scan, the focus of increased activity in the left side of the pelvis is localized to the pelvic kidney (arrowhead), a finding that is compatible with focal retention of FDG in the collecting system of the pelvic kidney. Again, note the areas of normal physiologic FDG uptake in the right ureter (arrows) and bladder.
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Figure 11b. Focal retention of FDG in a pelvic kidney. B = bladder. (a) FDG PET scan shows a focus of increased activity in the left side of the pelvis (arrowhead). Arrows indicate areas of normal physiologic FDG uptake in the right ureter. Normal uptake is also seen in the bladder. (b) CT scan shows a pelvic kidney (K). (c) On a PET-CT scan, the focus of increased activity in the left side of the pelvis is localized to the pelvic kidney (arrowhead), a finding that is compatible with focal retention of FDG in the collecting system of the pelvic kidney. Again, note the areas of normal physiologic FDG uptake in the right ureter (arrows) and bladder.
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Figure 11c. Focal retention of FDG in a pelvic kidney. B = bladder. (a) FDG PET scan shows a focus of increased activity in the left side of the pelvis (arrowhead). Arrows indicate areas of normal physiologic FDG uptake in the right ureter. Normal uptake is also seen in the bladder. (b) CT scan shows a pelvic kidney (K). (c) On a PET-CT scan, the focus of increased activity in the left side of the pelvis is localized to the pelvic kidney (arrowhead), a finding that is compatible with focal retention of FDG in the collecting system of the pelvic kidney. Again, note the areas of normal physiologic FDG uptake in the right ureter (arrows) and bladder.
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Figure 12a. Focal retention of FDG in an ileal conduit. B = bowel. (a) FDG PET scan shows an intense focus of increased FDG activity in the right lower abdomen (arrowhead). There is normal physiologic activity in the bowel and an accumulation of excreted FDG in an ostomy bag (O). (b) CT scan demonstrates a focal fluid collection (arrowhead), a finding that is compatible with an ileal conduit. No pathologic process is noted. (c) On a PET-CT scan, the focus of increased activity is localized to the ileal conduit (arrowhead), a finding that is compatible with focal retention of FDG in the ileal conduit. Again, note the normal physiologic activity in the bowel and the accumulation of excreted FDG in the ostomy bag (O).
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Figure 12b. Focal retention of FDG in an ileal conduit. B = bowel. (a) FDG PET scan shows an intense focus of increased FDG activity in the right lower abdomen (arrowhead). There is normal physiologic activity in the bowel and an accumulation of excreted FDG in an ostomy bag (O). (b) CT scan demonstrates a focal fluid collection (arrowhead), a finding that is compatible with an ileal conduit. No pathologic process is noted. (c) On a PET-CT scan, the focus of increased activity is localized to the ileal conduit (arrowhead), a finding that is compatible with focal retention of FDG in the ileal conduit. Again, note the normal physiologic activity in the bowel and the accumulation of excreted FDG in the ostomy bag (O).
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Figure 12c. Focal retention of FDG in an ileal conduit. B = bowel. (a) FDG PET scan shows an intense focus of increased FDG activity in the right lower abdomen (arrowhead). There is normal physiologic activity in the bowel and an accumulation of excreted FDG in an ostomy bag (O). (b) CT scan demonstrates a focal fluid collection (arrowhead), a finding that is compatible with an ileal conduit. No pathologic process is noted. (c) On a PET-CT scan, the focus of increased activity is localized to the ileal conduit (arrowhead), a finding that is compatible with focal retention of FDG in the ileal conduit. Again, note the normal physiologic activity in the bowel and the accumulation of excreted FDG in the ostomy bag (O).
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Figure 13a. False-negative result due to FDG activity in the bladder in a patient with recurrent ovarian cancer. (a) CT scan demonstrates minimal nodularity near the bladder dome (Tumor), a finding that proved to be metastatic disease at surgery. (b, c) FDG PET (b) and PET-CT (c) scans fail to show increased metabolic activity in the tumor nodule due to accumulation of excreted FDG in the bladder (B). There is also a focus of increased metabolic activity in an enlarged right inguinal node, a finding that is compatible with metastasis.
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Figure 13b. False-negative result due to FDG activity in the bladder in a patient with recurrent ovarian cancer. (a) CT scan demonstrates minimal nodularity near the bladder dome (Tumor), a finding that proved to be metastatic disease at surgery. (b, c) FDG PET (b) and PET-CT (c) scans fail to show increased metabolic activity in the tumor nodule due to accumulation of excreted FDG in the bladder (B). There is also a focus of increased metabolic activity in an enlarged right inguinal node, a finding that is compatible with metastasis.
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Figure 13c. False-negative result due to FDG activity in the bladder in a patient with recurrent ovarian cancer. (a) CT scan demonstrates minimal nodularity near the bladder dome (Tumor), a finding that proved to be metastatic disease at surgery. (b, c) FDG PET (b) and PET-CT (c) scans fail to show increased metabolic activity in the tumor nodule due to accumulation of excreted FDG in the bladder (B). There is also a focus of increased metabolic activity in an enlarged right inguinal node, a finding that is compatible with metastasis.
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Figure 14a. Apparent increased FDG activity (attenuation correction artifact) around hip replacements (H). B = bladder. (a) CT scan shows artifact from bilateral hip replacements. (b, c) Attenuation-corrected PET (b) and PET-CT (c) scans show apparent increased FDG activity (arrowheads) around the hip replacements. (d) Non-attenuation-corrected PET scan shows no increased activity, a finding that confirms that the "increased activity" on the attenuation-corrected image is due to reconstruction artifact. Normal physiologic FDG accumulation is seen in the bladder on all four scans.
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Figure 14b. Apparent increased FDG activity (attenuation correction artifact) around hip replacements (H). B = bladder. (a) CT scan shows artifact from bilateral hip replacements. (b, c) Attenuation-corrected PET (b) and PET-CT (c) scans show apparent increased FDG activity (arrowheads) around the hip replacements. (d) Non-attenuation-corrected PET scan shows no increased activity, a finding that confirms that the "increased activity" on the attenuation-corrected image is due to reconstruction artifact. Normal physiologic FDG accumulation is seen in the bladder on all four scans.
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Figure 14c. Apparent increased FDG activity (attenuation correction artifact) around hip replacements (H). B = bladder. (a) CT scan shows artifact from bilateral hip replacements. (b, c) Attenuation-corrected PET (b) and PET-CT (c) scans show apparent increased FDG activity (arrowheads) around the hip replacements. (d) Non-attenuation-corrected PET scan shows no increased activity, a finding that confirms that the "increased activity" on the attenuation-corrected image is due to reconstruction artifact. Normal physiologic FDG accumulation is seen in the bladder on all four scans.
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Figure 14d. Apparent increased FDG activity (attenuation correction artifact) around hip replacements (H). B = bladder. (a) CT scan shows artifact from bilateral hip replacements. (b, c) Attenuation-corrected PET (b) and PET-CT (c) scans show apparent increased FDG activity (arrowheads) around the hip replacements. (d) Non-attenuation-corrected PET scan shows no increased activity, a finding that confirms that the "increased activity" on the attenuation-corrected image is due to reconstruction artifact. Normal physiologic FDG accumulation is seen in the bladder on all four scans.
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Copyright © 2005 by the Radiological Society of North America.
