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B D Collier

Publications and source records attributed to B D Collier.

At least 37 records · Page 2Linked to original sources
PubMed1995

Detection of pulmonary embolism in patients with unresolved clinical and scintigraphic diagnosis: helical CT versus angiography.

OBJECTIVE: This study was designed to prospectively compare helical CT with pulmonary angiography in the detection of pulmonary embolism in patients with an unresolved clinical and scintigraphic diagnosis. SUBJECTS AND METHODS: Twenty patients with an unresolved suspicion of pulmonary embolism were evaluated with contrast-enhanced helical CT and with selective pulmonary angiography. An average of 11 hr separated the two studies. The CT scans were obtained during one 24-sec or two 12-sec breath-holds. CT scans were interpreted without knowledge of the results of scintigraphy or angiography. Selective pulmonary angiograms were obtained with knowledge of the findings on the ventilation/perfusion scan only. The sensitivity and specificity of CT were compared with those of angiography for central vessels (segmental and larger) only and for all vessels. RESULTS: Eleven of the 20 patients had proved pulmonary embolism (seven in central vessels and four in subsegmental vessels only). When only central vessels were analyzed, CT sensitivity was 86%, specificity was 92%, and the likelihood ratio was 10.7. However, when subsegmental vessels were included, CT results were 63%, 89%, and 5.7, respectively. CONCLUSION: In our subset of patients, helical CT was only 63% sensitive. Subsegmental emboli are difficult to diagnose. Pulmonary angiography remains the study of choice. CT has a limited role in the evaluation of acute pulmonary embolism.

Acute Disease↗
PubMed1995

Evaluation of regional cerebral blood flow in massive intracerebral calcifications.

Fahr's disease is histopathologically characterized by massive bilateral calcifications of the cerebral basal ganglia, the dentate nuclei of the cerebellum and both the cerebral and cerebellar cortices. We report a case of Fahr's disease in which a 99mTc-hexamethyl-propylenamine oxime (99mTc-HMPAO) brain SPECT study was used to evaluate regional cerebral blood flow to the calcified regions. There was markedly decreased perfusion to the basal ganglia bilaterally as well as decreased perfusion to the cerebral cortices that correlated well with the patient's clinical condition.

Adult↗
PubMed1995

Phosphorus-32-chromic phosphate for ovarian cancer: I. Fractionated low-dose intraperitoneal treatments in conjunction with platinum analog chemotherapy.

UNLABELLED: For many years, 32P-chromic phosphate (32P-CP) intraperitoneal instillations and platinum analogue chemotherapy have been used to treat disseminated ovarian cancer. To investigate possible enhancement of 32P-CP irradiation due to the concomitant administration of chemotherapy, in vitro studies were undertaken. Based on those laboratory investigations, a clinical regimen of combined 32P-CP and platinum analogue chemotherapy was developed. METHODS: In vitro enhancement of 32P-CP cytotoxicity by cisplatin was studied in cultured human ovarian adenocarcinoma (CHOA) cell lines and in a fibroblast cell strain. In addition, ovarian cancer cells obtained from the malignant abdominal ascites and pleural effusions of 10 individual patients were also studied ex vivo. As part of routine clinical care, 30 patients with disseminated ovarian adenocarcinoma underwent up to eight monthly cycles of platinum analogue chemotherapy with concomitant intraperitoneal instillation of 5 mCi of 32P-CP at each monthly chemotherapy cycle. RESULTS: There was an enhanced and possibly supra-additive effect of cisplatin on the cytotoxicity from 32P-CP irradiation. For the 30 patients, the survival rate at 3 yr was 63%. CONCLUSION: Phosphorus-32 CP low-dose intraperitoneal treatments in conjunction with platinum analogue chemotherapy is a promising approach for the treatment of disseminated intraperitoneal ovarian cancer.

Adenocarcinoma↗
PubMed1994

Misleading imaging results in the diagnosis of parathyroid cysts.

Enlarged cystic parathyroid glands, whether hyperfunctioning or nonfunctioning, are rare and their accurate preoperative diagnosis is a difficult task. The authors report two cases of patients with cystic neck masses studied by Tl-201-Tc-99m pertechnetate subtraction scintigraphy, computerized tomography, and ultrasonography. The diagnostic consensus of preoperative studies was that these lesions were thyroid nodules or parathyroid adenomas. Surgical removal and histopathologic examination of these masses revealed a cystic parathyroid gland and a cystic parathyroid adenoma, respectively. When a fluid-filled lesion in the neck deep to the lower pole of the thyroid gland is encountered, the possibility of a parathyroid cyst should be considered so that further diagnostic tests can be properly performed.

Adenoma↗
PubMed1994

Pedal radiocolloid lymphoscintigraphy in demonstration of a post-surgical lymphatic leak.

Radiocolloid lymphoscintigraphy is a very effective diagnostic procedure for dynamic evaluation of lymphatic flow. In this case report, the use of radiocolloid lymphoscintigraphy in detection of a post-surgical lymphatic leak is presented. Dynamic pedal lymphoscintigraphy with Tc 99m-antimony trisulfide colloid clearly demonstrated the site of the leak.

Humans↗
PubMed1993

New radiographic techniques for colorectal cancer.

Before surgical staging and resection, patients with primary colorectal cancer undergo a thorough diagnostic evaluation. The initial imaging study to identify a primary site of disease often is endoscopy, which frequently is supplemented with a double contrast barium enema. Once the presence of colorectal cancer has been established, new radiographic imaging techniques, including computed tomography (CT), magnetic resonance imaging (MRI), and special ultrasound (US) may be used. Clinical questions addressed by these special imaging techniques include detection of liver and lymph metastases and clarification of local extent of disease.

Colonic Neoplasms↗
PubMed1993

Detection of chronic coronary artery disease: value of pharmacologically stressed, dynamically enhanced turbo-fast low-angle shot MR images.

OBJECTIVE: The potential of MR imaging for evaluating myocardial perfusion and viability may make it the imaging procedure of choice for examining patients with ischemic heart disease. Accordingly, the purpose of this study is to determine the value of pharmacologically stressed, dynamically enhanced turbo-fast low-angle shot (FLASH) MR imaging in detecting chronic coronary artery disease. SUBJECTS AND METHODS: Five patients who had coronary angiography within the past 6-12 months were included in the study. After injection of 0.56 mg/kg of dipyridamole over 4 min, a bolus of 0.05 mg/kg of gadopentetate dimeglumine and subsequently 10 mCi (370 MBq) of 99mTc-sestamibi were injected. Short-axis turbo-FLASH images were obtained before injection and immediately, 1 min, 3 min, and 5 min after the injection of contrast material. Stress single-photon emission computed tomography (SPECT) images of the heart were obtained 60 min after the 99mTc-sestamibi injection. One and a half hours after an additional 30 mCi (1110 MBq) of 99mTc-sestamibi was injected, SPECT images were obtained with patients at rest. Prospective MR imaging evaluation of these five patients was performed by radiologists who did not know any of the imaging data. The MR imaging studies were compared with the near simultaneous 99mTc-sestamibi SPECT studies and with recent coronary angiograms. RESULTS: Thirteen myocardial segments were diagnosed as abnormal when 99mTc-sestamibi SPECT was used as the gold standard (12 reversible defects and one fixed defect). Twelve segments were normal on the 99mTc-sestamibi SPECT study. With SPECT as the gold standard, prospective MR imaging had a sensitivity of 77% and a specificity of 75%, whereas retrospectively it had a sensitivity of 92% and a specificity of 75%. With recent coronary angiography as the gold standard, prospective MR imaging had a sensitivity of 81% and a specificity of 100%. The quantitative data did not improve the accuracy of the qualitative analysis. CONCLUSION: Our results suggest that accurate prospective identification of chronic coronary artery disease may be possible with dynamically enhanced, pharmacologically stressed, turbo-FLASH MR imaging. Studies of additional patients to confirm this initial impression are warranted.

Adult↗
PubMed1993

Bone scintigraphy: Part 2. Orthopedic bone scanning.

Bone scanning provides a functional assessment of skeletal pathology not available with conventional radiography or special radiographic techniques such as CT and MRI. Bone scanning detects osteoblastic activity associated with many forms of orthopedic skeletal disease. Several of the more common orthopedic applications of bone scanning have been described above, while equally important topics such as prothesis loosening, avascular necrosis, and the reflex sympathetic dystrophy syndrome were not considered. Thus, for a great range of benign skeletal pathology, bone scanning can provide the orthopedic surgeon with practical information concerning the cause of the patient's pain, the true significance of otherwise questionable radiographic findings, the extent of disease and the results of orthopedic surgical treatment.

Arthrodesis↗
PubMed1993

Intraosseous meningioma: appearance on bone scintigraphy over five years.

While meningiomas are common intradural tumors, such lesions only rarely arise outside of the meninges. All meningiomas, however, may slowly enlarge causing concern for malignancy. We report the appearance of an intraosseous meningioma in the patient with a history of breast carcinoma where the lesion progressively enlarged over a period of 5 yr to reach approximately three times the original size.

Adult↗
PubMed1993

Current imaging strategies for colorectal cancer.

Endoscopy and barium enema examinations are used to identify the primary site of disease in patients with clinical suspicion of colorectal cancer. Once colorectal cancer has been confirmed by imaging studies and biopsy, preoperative evaluation is directed toward accurate disease staging. Most currently available imaging techniques are inaccurate for detecting transmural extension, perienteric spread of tumors and distant lymph node involvement. Although both computed tomography (CT) and magnetic resonance imaging (MRI) have an unacceptably low sensitivity for accurate staging, CT is clearly superior to MRI for detecting extrahepatic metastases. Transrectal ultrasonography, however, is a promising new method for detecting perirectal spread of disease. The diagnostic efficacy of MRI and intravenous dynamic hepatic CT for detecting liver metastases is approximately equal. CT during arterial portography is recommended before resection of solitary liver metastases. Chest radiography is also part of the routine preoperative evaluation. Bone scans are rarely performed in patients without the skeletal pain suggestive of bone metastases. During the years following surgery for colorectal cancer, many patients undergo special imaging studies to identify local tumor recurrence, secondary tumor growth elsewhere within the large bowel and both regional and distant spread of disease. Thus, for the patient with a sharply increasing carcinoembryonic antigen level, CT of the abdomen and liver is the current recommendation. Immunoscintigraphy is a new imaging modality that addresses some of the limitations of current diagnostic procedures for colorectal cancer. This procedure gives whole body information on disease extent, especially in the extrahepatic abdomen and pelvis, and can therefore contribute to patient management decisions.

Colorectal Neoplasms↗
PubMed1992

Diagnostic reliability of radionuclide ventriculography in detecting left ventricular hypertrophy. Echocardiographic and ECG correlations.

Left ventricular hypertrophy (LVH) is frequently present in patients referred for radionuclide ventriculography (RVG) for evaluation of left ventricular function. During interpretation of these studies, the nuclear medicine physician may have the subjective impression that increased septal thickening is present because of the abnormally prominent separation of the right and left ventricular blood pools. To examine the diagnostic reliability of this finding, we retrospectively reviewed the RVG studies of 43 consecutive patients and correlated the finding of subjectively increased septal thickness with established echocardiographic (ECHO) criteria and commonly used electrocardiographic (ECG) indices of LVH. Using standard ECHO measurements of septal thickness as a gold standard, RVG interpretation of septal thickening demonstrated a sensitivity of 0.69, specificity of 0.70, and accuracy of 0.70. When compared with standard ECG criteria for LVH, RVG performed quite favorably in the diagnosis of LVH confirmed by ECHO left ventricular mass index. We conclude that scintigraphic evidence of LVH should be reported when RVG studies are interpreted.

Adult↗
PubMed1992

Increased sacroiliac joint uptake after lumbar fusion and/or laminectomy.

Of 753 adult patients undergoing SPECT and planar bone scintigraphy for the evaluation of low back pain, 43 (6%) showed either unilateral or bilateral increased sacroiliac joint (SIJ) uptake. Five of the 58 abnormal joints were only identified with SPECT (9%), whereas 20 of the 58 abnormal joints were much more convincingly demonstrated by SPECT (34%). Fifteen of the 43 patients with increased SIJ uptake had undergone prior lumbar laminectomy and/or spinal fusion. Such spinal surgery can increase impact loading on the SIJ, leading to mechanical overload and sacroiliitis. Degenerative joint disease, trauma, or other benign pathology accounted for the remaining patients with increased SIJ uptake. The authors conclude that for patients with a history of lumbar spinal fusion and/or laminectomy, increased SIJ uptake usually is caused by altered spinal mechanics rather than malignancy or infection.

Adult↗
PubMed1992

High-resolution bone scintigraphy of the adult wrist.

Bony anatomic landmarks of the wrist (e.g., pisiform, hook of hamate, radioulnar joint, and styloid processes of the radius and ulna) were routinely identified in 28 adult patients examined for wrist pain. With the wrists prone and immobilized, bone scintigrams were obtained for 500,000 counts with an asymmetric (133 to 161 keV) Tc-99m energy window and either a converging (best choice) or straight-bore, high-resolution collimator. High-resolution scintigraphy precisely localized degenerative joint disease (nine patients), scaphoid fractures (five), pisiform fracture (one), lunate avascular necrosis (one), radioulnar arthritis (one), septic or inflammatory arthritis (six), ulnocarpal impingement (two), and reflex sympathetic dystrophy syndrome (two). Images obtained palm down with the wrist in ulnar deviation helped identify increased uptake within the scaphoid. Fracture and significant bone or joint disease were excluded in one patient.

Adult↗