Principles of Contrast Enhancement in Computerized Tomography

ABSTRACT:Contrast enhancement on computerized tomography (CT) scans has been used in directing therapy for presumed intracranial gliomas. However, for moderately anaplastic astrocytomas (MOAAS) and highly anaplastic astrocytomas (HAAS), it provides no information about proliferative potential. The bromodeoxyuridine (BUDR) labeling index (LI), however, indicates proliferative potential, correlating with histologic malignancy and survival. An LI < 1% is a favorable indicator; LI > 5% suggests more aggressiveness. To determine the correlation, if any, between BUDR LI and contrast enhancement, CT scans of 71 patients with cerebral hemisphere tumors labeled with BUDR were retrospectively reviewed. Among 36 MOAAS, the BUDR LI was < 1% in 77% of enhanced tumors and 61% of unenhanced tumors. Among 35 HAAS, it was < 5% in 56% of enhanced tumors and 90% of unenhanced tumors. Therefore, contrast enhancement on CT scans does not always correctly predict proliferative potential in these tumors, and biopsy and labeling studies are recommended before therapy.

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Significance of contrast enhancement in cranial computerized tomography after subarachnoid hemorrhage

Journal of Neurosurgery ◽

10.3171/jns.1984.60.2.0335 ◽

1984 ◽

Vol 60 (2) ◽

pp. 335-342 ◽

Cited By ~ 40

Author(s):

Thomas Doczi ◽

James Ambrose ◽

Sean O'Laoire

Keyword(s):

Subarachnoid Hemorrhage ◽

Contrast Enhancement ◽

Computerized Tomography ◽

Contrast Material ◽

Ct Scanning ◽

Visual Evaluation ◽

Content Type ◽

Before And After ◽

Subarachnoid Spaces ◽

Cranial Computerized Tomography

✓ Eighty patients with subarachnoid hemorrhage underwent computerized tomography (CT) scanning before and after administration of Conray contrast medium. Abnormal enhancement was seen in visual evaluation of the CT scans in 26 cases, in the regions bordering the subarachnoid spaces. Abnormal enhancement was associated with a poor clinical condition, angiographic spasm, and a poor outcome. Measurements of absorption values in the thalamus revealed significant increases in density after contrast enhancement in those patients whose scans showed abnormal enhancement in the regions bordering the subarachnoid spaces on visual evaluation. The authors suggest that the abnormal enhancement is parenchymal, in the gyri, and is not “subarachnoid.” They suggest that it is due to gyral hyperemia or extravasation of contrast material into the cortex resulting from breakdown of the blood-brain barrier, or a combination of both factors.

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Postoperative CT contrast enhancement following lobectomy for epilepsy

Journal of Neurosurgery ◽

10.3171/jns.1990.73.3.0392 ◽

1990 ◽

Vol 73 (3) ◽

pp. 392-395 ◽

Cited By ~ 21

Author(s):

Varun Laohaprasit ◽

Daniel L. Silbergeld ◽

George A. Ojemann ◽

Joseph M. Eskridge ◽

H. Richard Winn

Keyword(s):

Contrast Enhancement ◽

Computerized Tomography ◽

Contrast Material ◽

Residual Tumor ◽

Ct Scans ◽

Resection Margins ◽

Normal Brain ◽

Content Type ◽

Preoperative Ct ◽

Ct Contrast

✓ Contrast-enhanced computerized tomography (CT) is frequently utilized immediately after surgery to determine the presence of residual tumor, but the response of nontumor brain tissue is unclear. Consequently, the authors investigated the postoperative CT contrast enhancement in six patients undergoing lobectomy for epilepsy. Preoperative CT scans were obtained in all cases and revealed no enhancing lesions. All patients underwent craniotomy with electrocorticography while awake, followed by lobectomy. Computerized tomography scans with and without administration of contrast material were obtained on postoperative Days 3, 7, and 30. Edema, artifact, and enhancement of the resection margins were seen on postoperative Days 3 and 7, but had resolved in all patients by Day 30. It is concluded that postoperative CT scans for assessment of residual tumor are best obtained at 30 days or thereafter, when normal brain does not enhance and edema and artifact have diminished.

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Computerized Tomography of the Kidney: Tissue-Plasma Ratio of Contrast Enhancement with Bolus Injection and Renal Function

The Journal of Urology ◽

10.1016/s0022-5347(17)54016-1 ◽

1982 ◽

Vol 127 (4) ◽

pp. 721-723 ◽

Cited By ~ 3

Author(s):

Masayoshi Yokoyama ◽

Kiyotaka Watanabe ◽

Shinichi Inatsuki ◽

Kenji Ochi ◽

Masafumi Takeuchi

Keyword(s):

Renal Function ◽

Contrast Enhancement ◽

Computerized Tomography ◽

Bolus Injection ◽

Kidney Tissue ◽

Plasma Ratio

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Contrast enhancement by arterial perfusion during computerized tomography

Neuroradiology ◽

10.1007/bf00337546 ◽

1976 ◽

Vol 11 (3) ◽

pp. 119-121 ◽

Cited By ~ 8

Author(s):

C. G. Coin ◽

G. H. Wilson ◽

R. Klebanoff

Keyword(s):

Contrast Enhancement ◽

Computerized Tomography ◽

Arterial Perfusion

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Oligodendroglioma and cerebral cavernous angioma

Journal of Neurosurgery ◽

10.3171/jns.1985.62.1.0145 ◽

1985 ◽

Vol 62 (1) ◽

pp. 145-147 ◽

Cited By ~ 24

Author(s):

Chee Pin Chee ◽

Robin Johnston ◽

David Doyle ◽

Peter Macpherson

Keyword(s):

Intracranial Pressure ◽

Contrast Enhancement ◽

Computerized Tomography ◽

Vascular Malformation ◽

Signs And Symptoms ◽

Cavernous Angioma ◽

Raised Intracranial Pressure ◽

Content Type ◽

Vascular Component ◽

Fine Print

✓ The authors report a case of frontal lobe oligodendroglioma associated with a cavernous angioma. The patient presented with signs and symptoms of raised intracranial pressure. Computerized tomography with contrast enhancement failed to detect the vascular component. The clinical and pathological significance of the presence of this vascular malformation in an oligodendroglioma is discussed.

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