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B David Collier

Publications and source records attributed to B David Collier.

7 recordsLinked to original sources

Technical errors in planar bone scanning.

Optimal technique for planar bone scanning improves image quality, which in turn improves diagnostic efficacy. Because planar bone scanning is one of the most frequently performed nuclear medicine examinations, maintaining high standards for this examination is a daily concern for most nuclear medicine departments. Although some problems such as patient motion are frequently encountered, the degraded images produced by many other deviations from optimal technique are rarely seen in clinical practice and therefore may be difficult to recognize. The objectives of this article are to list optimal techniques for 3-phase and whole-body bone scanning, to describe and illustrate a selection of deviations from these optimal techniques for planar bone scanning, and to explain how to minimize or avoid such technical errors.

Artifacts↗

Dextrose solutions yield radiochemical impurities: the "sweet" scans.

OBJECTIVE: If additional chemicals are inadvertently introduced in the preparation of radiopharmaceutical kits, radiochemical impurities may be formed. We report our experience with erroneously diluting (99m)Tc-pertechnetate eluate with 5% dextrose solution rather than normal saline during the preparation of (99m)Tc-tetrofosmin, (99m)Tc-methylene diphosphonate (MDP), (99m)Tc-stannous colloid, and (99m)Tc-mebrofenin. METHODS: Scintigrams for 3 of the 4 radiochemicals unintentionally prepared with 5% dextrose were found to have an altered biodistribution. Therefore, radiopharmacy procedures for the day were reviewed, and instant thin-layer chromatography (ITLC) was performed. RESULTS: Scintigrams showed an altered biodistribution consistent with an impurity. Review of procedures that day uncovered the error of using 5% dextrose to dilute the (99m)Tc eluate. The altered biodistribution on (99m)Tc-stannous colloid, (99m)Tc-MDP, and (99m)Tc-mebrofenin scintigrams consisted of cardiac blood-pool activity (possibly as a result of slow clearance of (99m)Tc-dextrose), soft-tissue background activity (possibly as a result of interstitial distribution of (99m)Tc-dextrose), renal and bladder activity (possibly as a result of renal elimination of (99m)Tc-dextrose), and gallbladder activity (possibly as a result of hepatobiliary excretion of (99m)Tc-dextrose). Both scintigrams and ITLC showed no evidence of impurities for the (99m)Tc-tetrofosmin prepared using 5% dextrose. CONCLUSION: Unintended preparation of radiochemicals with 5% dextrose rather than normal saline often results in the production of impurities, possibly (99m)Tc-dextrose. Because some but not all commercial radiochemical kits prepared with 5% dextrose will suffer this fate, nuclear medicine physicians reviewing the day's images will be confronted with a confusing combination of expected and grossly abnormal findings.

Glucose↗

Nonosseous abnormalities on bone scans.

Although bone scanning is a test primarily concerned with skeletal abnormalities, important nonosseous findings are occasionally present on the images. To gauge the significance of such nonosseous uptake and, in particular, to determine whether these findings contain useful diagnostic information, the technical and medical staff in nuclear medicine must recognize the various patterns of nonbony uptake and understand their causes. The objectives of this article are to demonstrate the appearances of nonosseous uptake on bone scans, to categorize the forms of soft-tissue uptake, to emphasize technical artifacts leading to soft-tissue uptake, and to highlight the clinical significance of pathologic soft-tissue uptake.

Artifacts↗

Heterotopic ossification.

Heterotopic ossification (HO) is the presence of bone in soft tissue where bone normally does not exist. The acquired form of HO most frequently is seen with either musculoskeletal trauma, spinal cord injury, or central nervous system injury. For example, patients who have recently undergone total hip arthroplasty or have paraplegia after spinal cord injury are at risk for HO. The fever, swelling, erythema, and occasional joint tenderness seen in early HO can be difficult to distinguish from cellulitis, osteomyelitis, or thrombophlebitis. Bone scanning and other imaging tests frequently are used to distinguish between these diagnostic possibilities. As treatment or prophylaxis for HO, either a nonsteroidal antiinflammatory drug (such as indomethacin), a diphosphonate (such as ethane-1-hydroxy-1,1-diphosphate), or local radiation therapy is recommended. Before therapy begins, bone scanning may be requested to confirm the diagnosis of HO. In addition, surgical resection of HO is used to preserve joint mobility; however, HO is likely to recur and possibly progress if resection is undertaken before the lesion has become mature. With a view toward avoiding recurrent HO and other operative complications, serial quantitative bone scans are used as an aid to time surgical intervention.

Bone and Bones↗