Bone scanning

Stress or fatigue fractures are very painful. Most often symptoms occur after athletic activity or physical exertion. Gradually pain worsens and becomes more constant. Stress fractures do not show up on standard x-rays. A bone scan maybe used to confirm the diagnosis. Stress fractures usually occur in the weight-bearing bones of the lower leg and foot. Stress fractures of the tibia account for half of all stress fractures, resulting mostly from athletic activity. These stress fractures are often mistaken for shin splints. In addition to the tibia, the fibula and other small bones of the foot are prone to stress fractures. 

Fig. 1. Bone scan of a 75-year-old woman presented with acute onset of low back pain employing either Tc-medronate [25681-89-4] or Tc-oxidronate [14255-61-9]. The bone scan of (a) the anterior and (b) the posterior pelvis shows increased uptake in the region of the sacral bone (arrows). The bladder (arrowheads) is a normal route of tracer excretion and is also prominently identified in the image.

Imaging studies, such as CT, MRI, or bone scan, can be used to detect osteomyelitis and to determine the depth and extent of tissue destruction. 

Nuclear medicine scans Method of body imaging that uses a radioactive tracer material (e.g., technetium and gallium) to produce body images. For example, bone scans detect uptake and cellular activity in areas of inflammation. 

Francis, M.D. and Fogelman, I., in Fogelman, I. (ed.), Bone Scanning in Clinical Practice, Springer-Verlag, Berlin, Heidelberg, 1987, pp. 7-17. 

Tumor response is measured by clinical chemistry (e.g., liver enzyme elevation in patients with hepatic metastases) or imaging techniques (e.g., bone scans or chest x-rays). 

Bone scans were not performed, but typically in osteomalacia there is widespread under mineralization of osteoid, so unlike osteoporosis, osteomalacia is due to poor quality bone causing a loss of rigidity and strength, rather than a quantitative reduction ofbone. A condition in children, which is biochemically similar to osteomalacia, is rickets. Sufferers have misshapen bones of the head, spine and chest and typically bowed legs. 

Initial H P Performance status Chest X-ray Panendoscopy/biopsy Bone scan CT or MRI... 

Because of early dissemination, staging of patients with small-cell lung cancer is more extensive than for patients with NSCLC. It is important to rule out distant metastasis because it will change the role of thoracic radiation in the treatment of these patients. Staging should include a complete history and physical examination, CAT scans of chest and upper abdomen to include the liver and adrenal glands, brain MRI scan, bone scan, complete blood count, and a possible bone marrow aspiration and biopsy. 

A. Paget s disease is often asymptomatic and picked up on plain bone films. Patients with Paget s disease should have their serum calcium level determined to make sure that they are not hypercalcemic from excessive bone resorption, their serum alkaline phosphatase measured as a marker of new bone formation, a bone scan to determine whether other bones are involved, and a 24-hour urinary hy-droxyproUne measurement to assess bone resorption. The patient who has minimal involvement and is biochemically normal does not need pharmacological therapy. No studies indicate that early treatment slows progression in individuals with the more severe form of this disorder. 

Irradiation of a mixture of neon and nitric oxide gives no-carrier-added nitrosyl [ F]fluoride (ON[ F]F) [45,67], Hydrolysis yields [ F]fluoride that was proposed for bone scanning. ON[ F]F was designed with steroid labelling in mind in which addition to a double bond should lead to an a-[ F]fluoroketone entity, but this idea was not further pursued. 

M. Welch, J.F. Litton, P.P. Caspar, Production of F for bone scanning from the 2°Ne(d,alpha) F reaction via fluorine-18 labeled nitrosyl fluoride. A selective fluorinating agent, J. Nucl. Med. 12 (1971) 405. 

Schirrmeister et al. prospectively evaluated the clinical value of planar bone scans, SPECT and [ F]-labeled sodium fluoride in 53 patients with newly diagnosed lung cancer [193], Twelve of the 53 patients turned out to have bone metas-tases. [ F]-fluoride-PET detected all patients with bone metastases, whereas bone scan and SPECT produced false-negative results (6 vs. 1). An area under the curve analysis (ROC) proved p F]-fluoride-PET to be the most accurate whole-body imaging modality for screening of bone metastases in this study. 

M. Blau, W. Nagler, M.A. Bender, Fluorine-18 A new isotope for bone scanning,... 

K. Dziuk, A. Gabelmann, S.N. Reske, M. Hetzel, Prospective evaluation of the clinical value of planar bone scans, SPECT, and (18)F-labeled NaF PET in newly diagnosed lung cancer, J. Nucl. Med. 42(12) (2001) 1800-1804. 

Technetium is now moderately abundant because it accumulates in the decay products of nuclear power plants. Another isotope, technetium-99, has pharmaceutical applications, particularly for bone scans (Box 17.2). 

Sr 64 d EC y 0.51,0.013 Cyclotron 85Rb(p,n)83Sr — Bone scanning... 

S7mSr 2.83 h EC y 0.39 Cyclotron 87Sr(p,n)87Y(EC)87mSr 3.3 d Bone scanning and bone cancer detection... 

Tc(MDP)OH ,1 was prepared by a different means from that used for the 99mTc bone scanning agent, and was only one of several products formed, its structure does provide a detailed insight into possible "mTc-MDP binding modes. 

The radioisotope most widely used today is technetium-99m, whose short half-life of 6.01 hours minimizes a patient s exposure to harmful effects. Bone scans using Tc-99m, such as that shown in Figure 22.12a, are an important tool in the diagnosis of cancer and other pathological conditions. 

Shrinkage in tumor size is a useful measure of clinical response, and this effect can be demonstrated by physical examination, chest film or other x-ray, or special scanning procedures such as bone scanning (breast, prostate cancer), CT scan, magnetic resonance imaging (MRI), or ultrasonography. 

Spencer RP, Lange RC, Treves S. 1971. Use of 135mBa and 131Ba as bone scanning agents. J Nucl Med 12 216-221. 

---