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Comparison of plain radiography, conventional tomography, and computed tomography in detecting intrathoracic lymph node metastases from lung carcinoma.

Forty-two patients with T2 bronchogenic carcinoma were evaluated with plain radiography, conventional 55 degrees oblique hilar and anteroposterior mediastinal tomography, and computed tomography (CT) to compare their accuracy in assessing mediastinal and hilar nodal metastases. Definitive staging was achieved by thoracotomy and histopathological evaluation of resected specimens. All modalities demonstrated about the same accuracy; however, in the 25 patients with hilar and/or mediastinal lymphadenopathy, CT of the mediastinum was more sensitive but not more specific than the other two and conventional tomography was no more accurate than CT for hilar evaluation. Overall, no technique was accurate enough for routine staging; their value may lie in directing biopsy or in treatment planning in patients with inoperable disease.

Carcinoma, Bronchogenic↗

Etiology of solitary extrapulmonary positron emission tomography and computed tomography findings in patients with lung cancer.

PURPOSE: The aim of this prospective study was to assess the incidence and the nature of solitary extrapulmonary [18F] fluorodeoxyglucose (FDG) accumulations in patients with non-small-cell lung cancer (NSCLC) staged with integrated positron emission tomography and computed tomography (PET/CT) and to evaluate the impact on management. PATIENTS AND METHODS: A total of 350 patients with NSCLC underwent whole-body PET/CT imaging. All solitary extrapulmonary FDG accumulations were evaluated by histopathology, further imaging, or clinical follow-up. RESULTS: PET/CT imaging revealed extrapulmonary lesions in 110 patients. In 72 patients (21%), solitary lesions were present. A diagnosis was obtained in 69 of these patients, including 37 (54%) with solitary metastases and 32 (46%) with lesions unrelated to the lung primary. Histopathologic examinations of these 32 lesions revealed a second clinically unsuspected malignancy or a recurrence of a previous diagnosed carcinoma in six patients (19%) and a benign tumor or inflammatory lesion in 26 patients (81%). The six malignancies consisted of carcinoma of the breast in two patients, and carcinoma of the orbit, esophagus, prostate, and non-Hodgkin's lymphoma in one patient each. Benign tumors and inflammatory lesions included eight colon adenomas, four Warthin's tumors, one granuloma of the lower jaw, one adenoma of the thyroid gland, one compensatory muscle activity due to vocal chord palsy, two occurrences of arthritis, three occurrences of reflux esophagitis, two occurrences of pancreatitis, two occurrences of diverticulitis, one hemorrhoidal inflammation, and one rib fracture. CONCLUSION: Solitary extrapulmonary FDG accumulations in patients with newly diagnosed lung cancer should be analyzed critically for correct staging and optimal therapy, given that up to half of the lesions may represent unrelated malignancies or benign disease.

Adult↗

Comparison of whole lung tomography and computed tomography for detecting pulmonary nodules.

Detecting pulmonary metastasis is important when planning surgical therapy, radiotherapy, or chemotherapy in patients with known malignancy. A series of 91 patients was studied by both whole lung tomography and computed tomography (CT) of the lungs. More pulmonary nodules were detected with CT than with whole lung tomography in 32 (35%) of the patients. Of the 91 patients in the study, 31 had resection of some or all of the pulmonary nodules. In 27 patients, the nodules were primary or metastatic malignant lesions. Bilateral pulmonary nodules were detected with CT in 13 patients when whole lung tomography had demonstrated nodules in only one lung. CT has replaced whole lung tomography as the method preferred by the authors for detecting pulmonary nodules in selected patients at risk to develop pulmonary metastasis.

Adolescent↗

Preoperative image fusion of fluoro-2-deoxy-D-glucose-positron emission tomography and computed tomography data sets in oral maxillofacial carcinoma: potential clinical value.

OBJECTIVE: The aim was to evaluate the clinical and therapeutic value of digital image fusion of 2-[18]-fluoro-2-deoxy-D-glucose (F18-FDG) positron emission tomography (PET) and computed tomography (CT) in patients suffering from an oral maxillofacial carcinoma. METHODS: Seventeen patients (11 male, 6 female; age range: 45-89 years) suffering from an oral maxillofacial carcinoma underwent CT and F18-FDG-PET (333-370 MBq). The data of the 2 imaging modalities were fused on an image workstation. This image fusion was then visualized in the axial, coronal, and sagittal planes. RESULTS: PET showed a high pathologic FDG uptake in the tumor in 17 of 17 patients. CT detected the tumor in 12 of 17 patients. The image fusion of FDG-PET and CT showed the tumor in 17 of 17 patients. The final diagnosis was carcinoma of the mandible in 9 of 17 patients, carcinoma of the mouth floor in 3 of 17 patients, carcinoma of the tongue in 3 of 17 patients, carcinoma of the roof of the mouth in 1 of 17 patients, and carcinoma of the parotis gland in 1 of 17 patients. CONCLUSIONS: Preoperative image fusion of FDG-PET and CT data sets in oral maxillofacial carcinoma is possible in the clinical routine. Combined morphologic (CT) and functional (PET) imaging improves tumor localization even if the tumor is hardly visible on CT because of the artefacts of dental metallic implants (3/17 patients) or because of the small size of the tumor (2/17 patients). Image fusion is helpful for planning possible surgery (visual models) or radiotherapy (exact region of interest).

Aged↗

Use of relocatable stereotactic frame to integrate positron emission tomography and computed tomography images: application in human malignant brain tumours.

A stereotactic head frame has been developed which is accurately relocatable over an extended period of time, is non-invasive, and yet is rigidly fixed relative to the patient's skull. Eight patients with malignant brain tumours were studied by positron emission tomography scanning using 18FUDR and computed tomography scan. Serial biopsies were performed and were studied by routine histological methods and using the monoclonal antibody Ki67.

Antigens, Surface↗

Angio-computed tomography and dynamic computed tomography in staging of renal cell carcinoma.

Dynamic computed tomography and angio-tomography combine criteria generated by CT with those of angiography and are advocated by the author to improve staging of renal cell carcinoma. Dynamic CT was performed in 29 patients and angio-CT in 12 patients in this group. Rapid acquisition of data permits generation of a CT section in intervals of 1 to 6 seconds, which in turn reflects arterial, capillary, and venous transit of contrast medium through tissues. The propensity for dense enhancement of renal cell carcinoma makes possible positive identification of tumor elements. This feature proved accurate for the assessment of local extension of renal neoplasms in all 29 patients, involvement of the renal vein by tumor in 9/10, involvement of the inferior vena cava by tumor in 6/6, and involvement of regional nodes by tumor in 6/8.

Adenocarcinoma↗

Computed-tomography-based computer preoperative planning for total hip arthroplasty.

For precise preoperative planning in total hip arthroplasty (THA), we developed a technique of computed tomography (CT)-based computer preoperative planning and compared this technique with the single X-ray and template method generally used. The subjects of this study were 42 hips in 38 patients who underwent THA using a cementless total hip system. Preoperatively, a standard anteroposterior X-ray of the hip was taken, and conventional preoperative planning was done with a template of the total hip system. Transverse images were obtained using a helical CT scanner, and a CT-based computer preoperative plan was performed on true coronal slice images of the proximal femur reconstructed from CT data. Postoperatively, 29 hips (69%) showed good proximal fit of the femoral component to the medial endosteal line. Of the 20 hips with good proximal fit on preoperative X-ray planning, 12 hips had good proximal fit on postoperative X rays. Sensitivity and specificity of the proximal fit on X-ray templating were 41 and 23%, respectively. In 27 of 28 hips with good proximal fit on reconstructed CT images preoperatively, the postoperative X ray revealed good proximal fit. Sensitivity and specificity of the proximal fit on computer planning were 93 and 86%, respectively. Twelve hips with good proximal fit on preoperative templating, the reconstructed images, and the postoperative X ray had 20 degrees or less of combined femoral neck anteversion and external rotational contracture of the hip on the X-ray table. Eight hips with good proximal fit on preoperative templating and proximal poor fit on the reconstructed images had 17-65 degrees of combined version and rotational contracture. In 16 hips with poor proximal fit on preoperative templating and good proximal fit on the reconstructed images, the combined version and rotational contracture ranged from 17 to 69 degrees. When combined femoral neck anteversion and external rotational contracture of the hip is less than 15 degrees, the simple X-ray and template method might be sufficient for THA planning. Otherwise, the CT-based method of preoperative planning is recommended.

Arthroplasty, Replacement, Hip↗

Advantages of positron emission tomography over computed tomography in mediastinal staging of non-small cell lung cancer.

BACKGROUND: New treatment algorithms in early stage non-small cell lung cancer (NSCLC) involving preoperative chemotherapy require accurate clinical staging of the mediastinum. This study compares the accuracy of 2-[fluorine-18]fluoro-2-deoxy-d-glucose (FDG) positron emission tomography (PET) scanning with that of computed tomography (CT) scanning in the clinical staging of non-small cell lung cancer. MATERIALS AND METHODS: A retrospective review was performed on 52 patients with NSCLC who were evaluated with both CT and PET scans. All patients had their mediastinal lymph nodes sampled by mediastinoscopy or at the time of thoracotomy for pulmonary resection. Each imaging study was evaluated separately and correlated with histopathologic results. RESULTS: For detecting mediastinal metastases the sensitivities of PET and CT scans were 67 and 50%, respectively; specificities were 91 and 65%, respectively; accuracies were 88 and 63%, respectively; positive predictive values were 50 and 16%, respectively; negative predictive values were 95 and 88%, respectively. PET scans were significantly better than CT scans at detecting mediastinal metastases (PET, 4/8; CT, 3/19) (P = 0.01). CONCLUSIONS: PET scanning is superior to CT scanning for clinical staging of the mediastinum in NSCLC. A more confident decision regarding stratification of patients into current treatment algorithms can be made when the decision is based on PET scanning rather than the current "gold standard" of CT scanning.

Algorithms↗

Multiplanar imaging in the preoperative assessment of metallic intraocular foreign bodies. Helical computed tomography versus conventional computed tomography.

OBJECTIVE: This study aimed to compare the effectiveness of helical computed tomography (CT) versus conventional CT in the preoperative assessment of metallic intraocular foreign bodies on axial, coronal, and multiplanar reconstruction images in clinical routine. DESIGN: Prospective comparative trial, alternate assignment of consecutive patients. PARTICIPANTS: Eighteen patients with penetrating eye injuries and suspected metallic intraocular foreign bodies were studied. INTERVENTION: Alternate patients were assigned to undergo either helical CT or conventional CT in the axial plane. Both the helical and the conventional data were transferred to a workstation, and reconstructions in the coronal and sagittal planes were performed. Additional direct coronal scanning was performed only when necessary for preoperative assessment. MAIN OUTCOME MEASURES: The quality of the directly obtained axial and coronal, as well as the reconstructed coronal and sagittal images, was assessed for each, imaging method based on the ability to detect and accurately localize foreign bodies. The size of the foreign bodies was measured and compared to the actual diameter. Total examination time and radiation dose delivered to the lens were measured for each imaging method. RESULTS: All foreign bodies were detected by each scanning method on the axial, the coronal, and on the reconstructed planes. The quality of the axial images was similar for helical and conventional CT. The helical technique provided high-quality reconstructed images comparable in quality to the directly obtained coronal planes in conventional CT. Reconstructions by conventional technique were not useful for preoperative assessment. The examination time for the total orbital volume was 18 seconds for helical CT examinations and 52 seconds for conventional CT examinations. Radiation dose delivered to the lens for the complete examination was 35 mGy for helical CT axial scanning, 56 mGy for conventional CT axial scanning, and 63 mGy for conventional CT coronal scanning. CONCLUSIONS: Helical CT multiplanar imaging offers several significant advantages for the preoperative assessment of metallic intraocular foreign bodies compared to the conventional CT technique in clinical practice, including short examination time, reduced motion artifacts, reduced radiation exposure, and the ability to obtain diagnostically useful coronal and sagittal reconstruction images without the need for additional scanning.

Adolescent↗

Comparison of spiral computed tomography versus conventional computed tomography multiplanar reconstructions of a fracture displacement phantom.

PURPOSE: The capabilities of spiral computed tomography (CT) versus conventional CT to represent minimal fracture displacements on multiplanar reconstruction images in a phantom model were evaluated. MATERIALS AND METHODS: A displacement phantom was created from Teflon and was scanned with conventional and spiral CT, at slice collimations of 2 mm, 3 mm, and 5 mm. Three Z-axis interpolation algorithms (360_LI, 180_LI and 180_HI) were employed to process the spiral image data into planar images. Displacements of 5 mm or less were represented in the phantom, and the resultant multiplanar reconstructions were analyzed for the precision of displacement representation. Specifically, the edge profiles of the reconstructed images were measured and compared. RESULTS: Spiral CT reconstruction edge profiles were similar to those of conventional CT when minimal table increments (3 mm/sec or less), and an advanced interpolation algorithm (180_LI) was employed. Images obtained with 360_LI interpolation manifested the effect of widened slice profile even when employing minimal table speeds. CONCLUSIONS: With minimal table increment (3 mm/sec or less) and a high-order interpolation algorithm (180_LI), spiral-CT-derived reconstructions demonstrate similar edge profile resolution to reconstructions obtained from conventional CT.

Algorithms↗

Comparison of 18-fluoro-2-deoxyglucose positron emission tomography and computed tomography in detection of cervical lymph node metastases of nasopharyngeal carcinoma.

Neck lymph nodes (LNs) from 18 patients with nasopharyngeal carcinoma (NPC) were evaluated with 18-fluoro-2-deoxyglucose positron emission tomography (FDG-PET). Eighteen NPC patients underwent head and neck FDG-PET and computed tomography (CT) for detection of suspected neck LN metastases. For final diagnosis, biopsies were taken from neck LNs with discordant findings between FDG-PET and CT. Meanwhile, standard uptake values (SUVs) of the FDG-PET images were calculated to differentiate metastatic LNs from benign LNs. A total of 90 neck LNs found on either FDG-PET or CT were evaluated. In addition to 27 concordant positive results and 42 concordant negative LN results, biopsy findings revealed 11 metastatic LNs that were detected by FDG-PET but not by CT. However, the SUVs of the 11 metastatic LNs and 7 benign LNs were not significantly different. The CT scanning showed positive findings for I metastatic LN with negative FDG-PET findings. In addition, the tumor stage was upgraded in 5 patients on the basis of FDG-PET findings. In comparison with CT, FDG-PET has a higher potential for detecting neck LN metastases of NPC and assessing NPC tumor stage.

Adult↗

Clinical usefulness of computed tomography arteriography and computed tomography during arterial portography for the diagnosis of early and early advanced hepatocellular carcinoma.

OBJECTIVE: We examined the clinical usefulness of two techniques of Angio Computed tomography (CT), namely, CT arteriography (CTA) and CT during arterial portography (CTAP), for the diagnosis of early hepatocellular carcinoma (HCC) and early advanced HCC. MATERIALS AND METHODS: The subjects were six patients with a total of seven lesions: three had one early HCC lesion each, and three had four early advanced HCC lesions between them. There were five men and one woman, aged 61 approximately 73 years (mean: 65 years). A catheter was inserted into each inguinal artery according to Seldinger's method, and the results of CTA and CTAP were compared with those of conventional CT. RESULTS: Visualization of tumor borders, arterial blood feeding areas, and portal blood flow areas gave results equal to or better than those of conventional CT. CONCLUSIONS: A combination of CTA and CTAP is useful for the diagnosis of early HCC and early advanced HCC.

Aged↗

Radiologic diagnosis of liver metastases in colo-rectal carcinoma. Prospective evaluation of the accuracy of angiography, ultrasonography, computed tomography and computed tomographic angiography.

To evaluate the accuracy of radiologic methods in liver metastases from colo-rectal carcinoma, a prospective investigation of 71 patients was performed. These patients were examined by angiography, ultrasound (US), computed tomography (CT) and computed tomographic angiography (CTA). The primary aim of the investigation was to determine the accuracy of CTA. The results of these examinations were then compared with the results from inspection and palpation of the liver at laparotomy. An analysis of liver tumor distribution, as well as a lesion-by-lesion analysis, was performed. In 20 patients, tumor growth was found in the liver in 36 lobes/segments at laparotomy. Three patients called false positives (angiography 2, US, CT and CTA 3 patients) turned out to be true positives since the lesions were overlooked at operation. The changes in sensitivity obtained when these patients are considered are given in parentheses. Of the lobes/segments affected by tumor growth at surgery, angiography revealed 47 (48) per cent, US 69 (71) per cent, CT 80 (82) per cent and CTA 83 (84) per cent. At a lesion-by-lesion analysis, angiography showed 33 per cent, US 69 per cent, CT 61 per cent and CTA 76 per cent of the lesions. Because of a larger number of false positives recorded with CTA compared with CT the former examination is not suitable as a single method for evaluating resectability of liver metastases.

Adult↗

Detection of recurrent and metastatic colorectal cancer: comparison of positron emission tomography and computed tomography.

BACKGROUND: This study evaluates the clinical value of positron emission tomography (PET) with 2-[F-18] fluoro-2-deoxy-D-glucose (FDG) as compared to computed tomography (CT) in patients with suspected recurrent or metastatic colorectal cancer (CRC). METHODS: A retrospective review of the records of 58 patients who had FDG-PET for evaluation of recurrent or advanced primary CRC was performed. FDG-PET results were compared with those of CT and correlated with operative and histopathologic findings, or with clinical course and autopsy reports. RESULTS: Recurrent or advanced primary CRC was diagnosed in 40 and 11 patients, respectively. The sensitivity and specificity of FDG-PET were 91% and 100% for detecting local pelvic recurrence, and 95% and 100% for hepatic metastases. These values were superior to CT, which had sensitivity and specificity of 52% and 80% for detecting pelvic recurrence, and 74% and 85% for hepatic metastases. FDG-PET correctly identified pelvic recurrence in 19 of 21 patients; CT was negative in 6 of these patients and equivocal in 4. FDG-PET was superior to CT in detecting multiple hepatic lesions and influenced clinical management in 10 of 23 (43%) patients. CONCLUSION: FDG-PET is more sensitive than CT in the clinical assessment of patients with recurrent or metastatic CRC, and provides an accurate means of selecting appropriate treatment for these patients.

Adult↗

Noninvasive characterization of myocardial molecular interventions by integrated positron emission tomography and computed tomography.

OBJECTIVES: We sought to investigate the usefulness of integrated positron emission tomography (PET) and computed tomography (CT) for in vivo characterization of an angiogenesis-directed molecular intervention. BACKGROUND: Controversies about the effectiveness of molecular therapies for cardiovascular disease have prompted the need for more powerful noninvasive imaging techniques. METHODS: In a model of regional adenoviral transfer of the VEGF(121) gene to myocardium of healthy pigs, PET-CT using multiple molecular-directed radiotracers was employed. RESULTS: Two days after gene transfer, successful transgene expression was noninvasively confirmed by a reporter probe targeting co-expressed HSV1-sr39tk reporter gene. The CT-derived ventricular function and morphology remained unaltered (left ventricular ejection fraction 57 +/- 5% in adenovirus-injected animals vs. 53 +/- 5% in controls; p = 0.36). Increased regional perfusion was identified in areas overexpressing VEGF (myocardial blood flow during adenosine-induced vasodilation 1.47 +/- 0.49 vs. 1.14 +/- 0.27 ml/g/min in remote areas; p = 0.01), corroborating in vivo effects on microvascular tone and permeability. Finally, regional angiogenesis-associated alpha(v)beta3 integrin expression was not enhanced, suggesting little contribution to the perfusion increase. Fusion of CT morphology and tracer-derived molecular signals allowed for accurate regional localization of biologic signals. Findings were validated by control vectors, sham-operated animals, and ex vivo tissue analysis. CONCLUSIONS: Integrated PET-CT has the potential to dissect cardiovascular biologic mechanisms from gene expression to physiologic function and morphology. The VEGF overexpression in healthy myocardium increases myocardial perfusion without significant up-regulation of alpha(v)beta3 integrin adhesion molecules early after the intervention.

Animals↗

Combined FDG-positron emission tomography and computed tomography for the detection of ovarian cancer recurrence in an inguinal hernia sac.

BACKGROUND: Ovarian cancer recurrence presenting in an inguinal hernia sac is rare. Only 1 case of malignant ovarian cancer growing into an inguinal hernia sac has been reported in the English literature. Combined positron emission tomography (PET) and computed tomography (CT) may have a potential role in the early detection and anatomical localization of recurrent ovarian cancer. CASE REPORT: This is the first case of occult metastasis from ovarian cancer recurrence growing in a right inguinal hernia sac identified using combined FDG-PET/CT. CONCLUSION: Preoperative combined FDG-PET/CT imaging may have utility in the detection and anatomic localization of occult ovarian cancer recurrence, which may increase the likelihood of complete resection.

Female↗

[Comparative studies on imaging artificial bone lesions--conventional tomography and computed tomography].

Conventional tomography (T) and computer tomography (CT) were used for examining 97 artificial bone lesions at various sites. The purpose of the study was to determine how far CT can replace T in the diagnosis of skeletal abnormalities. The results have shown that modern CT, particularly in its high resolution form, equals T and provides additional information (substrate of a lesion, its relationship to neighbouring tissues, simultaneous demonstration of soft tissues etc.). These cannot be shown successfully by T. It follows that CT is indicated as the primary method of examination for lesions of the facial skeleton, skull base, spine, pelvis and, to some extent, extremities.

Animals↗