"10 mg toradol visa, treatment pain legs".

Z. Garik, M.A., M.D.

Associate Professor, Medical College of Georgia at Augusta University

The reason for the discrepancy in the results is unclear since the doses are essentially the same, but it may be related to the small numbers treated (four per study) and to the longer duration of the 1971 study. The major findings include (1) histological changes in the thyroid gland indicative of both stimulation of the gland. Total thyroxine (T4) and free T4 (T4 index) were significantly lower (approximately 10%) in a group of 55 transformer maintenance workers compared to a comparison control group of workers (Emmett et al. The transformer workers were primarily exposed to Aroclor 1260 at levels ranging from 0. Mean thyroid volume was significantly greater in the workers compared to the control group (18. Although larger thyroid volume could reflect a difference in the iodine intakes between the two groups, the investigators indicated that this was not likely because iodine intakes were considered sufficient in Slovakia and urinary iodine concentrations were similar in the worker and control groups (data not reported). In a case-control study of the Taiwan Yu-Cheng cohort, 795 exposed subjects and 693 sex- and age-matched controls were interviewed for information about health and medical history (Guo et al. The results of these studies have been mixed, with negative, positive, or no correlations observed. The subjects in this study are from the North Carolina Breast Milk and Formula Project cohort summarized in Section 3. Mean thyroid volume was significantly greater in the group who lived near the factory compared to the control group (9. As with the worker cohort (discussed with the occupational studies), the investigators indicated that a difference in the iodine intakes between the two groups was not likely because iodine intakes were considered to be sufficient and urinary iodine concentrations were similar in the two groups (data were not reported). An ongoing epidemiologic study is investigating the potential for health effects in Native Americans from exposure to persistent toxic substances (Dellinger et al. Fish consumption, species consumed, and medical histories were obtained from 541 Native Americans on eight reservations in Minnesota, Wisconsin, and Michigan. Although many of the populations examined had thyroid hormone levels within normal ranges, many of these studies also showed statistically significant differences in circulatory thyroid hormone levels in exposed cohorts compared to unexposed controls. Various effects on the thyroid gland and thyroid hormone system have been observed in rats exposed to Aroclor 1254 by the oral route. Typical findings, depending on the dose, include hyperplasia, hypertrophy, and increased vacuolization of follicular cells, depletion of follicular colloid and reduced follicular size, and thyroid enlargement (Collins and Capen 1980a; Collins et al. Additional abnormalities have also been noted when the gland has been examined at the ultrastructural level. Thus, while a general consensus has emerged that Aroclor 1254 produces a stimulation of the thyroid gland and thyroid hormone production (Byrne et al. It is likely that both contribute to varying degrees depending on the dosage and duration of exposure (Saeed and Hansen 1997). It is important to emphasize that characteristic structural changes that have been attributed to Aroclor 1254 may not be apparent when the gland is viewed only at the light microscopic level, which has been the approach used in most studies. Experimental studies that provide evidence for Aroclor-mediated effects on the thyroid gland and/or thyroid hormone status are noted below. Rats were fed 5, 50, or 500 ppm Aroclor 1254 in food for 4 weeks (approximately 0. Ultrastructural changes in the thyroid were evident at the lowest exposure level and became more pronounced and evident with light microscopy at the 50 ppm exposure level (4. Thyroid lesions in rats that were exposed to 500 ppm for 6 weeks followed by 250 ppm for 6 weeks were largely absent after a subsequent 12 weeks on a control diet, suggesting substantial recovery, and were not evident at all after a period of 35 weeks on the control diet (Collins and Capen 1980a). Thus, the observed lesions in this study and at these doses appeared to be reversible. In Sprague-Dawley rats, serum levels of T4 decreased when rats received daily gavage dosages of $0. The lack of effect of this dose of Aroclor 1254 on the histological status of the thyroid in the Sprague-Dawley rat, in comparison to histological changes observed in Osborne-Mendel rats at similar dosages and durations (Collins and Capen 1980a; Collins et al. In chronic-duration studies, enlarged thyroid glands and follicles with desquamated cells were observed in Rhesus monkeys exposed to 0. The incidence of follicular cell hyperplasia (generally minimal or mild) was increased in a non-dose-related pattern in male rats that were fed Aroclor 1242, 1254, or 1260 for 24 months at dose levels of $2. This thyroid lesion was not observed following exposure to similar doses of Aroclor 1016 in male rats or Aroclor 1016, 1242, 1254, or 1260 in female rats.

The observation about expansion must be made with caution because of the extreme intensity of uptake and "blooming" of the recorded activity. Acute fractures generally result in a three-phase positive scintigram, with chronic or partially healed fractures typically positive only on delayed images. Ninety-five percent of fractures are positive after 3 days, and in patients under the age of 65, essentially all fractures are positive by this time. Advanced age and debilitation are factors contributing to delayed visualization of fractures. The maximum degree of fracture uptake occurs 7 or more days after trauma, and delayed imaging in this time frame is recommended in difficult or equivocal cases. Occasionally, decreased uptake is seen acutely as a result of compromised vascular supply. The time a fracture takes to return to normal on the bone scan depends on location, stability, and the degree of damage to the skeleton. Approximately 60% to 80% of nondisplaced uncomplicated fractures revert to normal in 1 year, and more than 95% revert in 3 years (Table 7-5). Structural deformity and posttraumatic arthritis were the most common reasons for prolonged positive studies. Patients undergoing metastatic skeletal survey should be routinely asked about prior trauma. Craniotomy typically leaves a rim pattern at the surgical margin that may persist for months postoperatively. Rib retraction during thoracotomy can elicit periosteal reaction and increased uptake without actual resection of bone being involved. Bone resections are recognized as photon-deficient areas, although small laminectomies are usually not appreciated scintigraphically. Areas of the skeleton receiving therapeutic levels of external beam ionizing radiation characteristically demonstrate geometrical decreased uptake within 6 months to 1 year after therapy. The mechanism is probably decreased osteogenesis and decreased blood flow to postirradiated bone. Child Abuse the generally high sensitivity of skeletal scintigraphy would seem to make it an ideal survey test in cases of B Figure 7-28. The unusually large number of rib lesions raised the suspicion of metabolic bone disease rather than metastases. Distribution of Increased Skeletal Uptake in Hyperparathyroidism Diffuse axial Periarticular Skull Mandible, fascial bones Costochondral junctions Sternum Lungs Stomach 116 NuclearMedicine:TheRequisites A B Figure 7-29. Whole-body (A) and spot images (B) of a patient with long-standing renal failure show classic skeletal changes of severe renal osteodystrophy. Abnormal activity is seen in the face and skull and the distal ends of the long bones. Focal uptake in the left scapula was a fracture although brown tumors can have a similar appearance. A and B, the absence of soft tissue uptake with a superscan appearance even more striking than seen in metastatic disease. The native kidneys failed, and a renal transplant is noted in the right iliac fossa. Note the increased axial skeletal uptake and paucity of soft tissue background activity. However, in practice, radiographic skeletal survey is more sensitive than bone scintigraphy because of its ability to demonstrate old fractures that have healed, subtle fractures along growth plates with their normally high levels of uptake, and calvarial fractures in young children that may be difficult to see on bone scan. Scintigraphy is often reserved for cases of suspected child abuse when radiographs are unrevealing. Complex Regional Pain Syndrome Complex regional pain syndrome, previously known as reflex sympathetic dystrophy, is an exaggerated response to injury and immobilization with sensory, motor, and 117 autonomic features. Although presentation is variable, patients typically have pain, edema, and muscle wasting in an affected extremity. The classic pattern of unilaterally increased flow and blood pool activity with increased periarticular uptake on delayed images is seen less than 50% of the time but provides the highest diagnostic accuracy. Early disease (up to 5-6 months) usually shows increased blood flow (Fig 7-34), but blood flow may be normal or decreased later in the course of the disease. The periarticular uptake on delayed images is found in most cases (>95%), although specificity is lower if this finding is seen without the increased blood flow.

Experimental protocols with beta-emitters such as iodine-131, yttrium-90, and lutetium-177 labeled to octreotide have been used to treat poorly controlled neuroendocrine tumors. Some sites have used even higher doses of In-111 with its Auger electron emissions for therapy. The primary tumor was not seen with lesions in the abdomen corresponding to adenopathy. Indium-111 Pentetreotide Sensitivity 269 in Various Applications more aggressive, poorly differentiated cases. I-123 and I-131 Meta-iodo-benzyl-guanidine Use of adrenal medullary scintigraphy has been increasing at many centers, because it has proved valuable for the diagnosis, staging, and management of adrenergic neuroectodermal tumors, particularly pheochromocytomas, extraadrenal paragangliomas, and neuroblastomas. Although it has been labeled for clinical use with both I-131 and I-123, the I-123 radiolabel is generally preferred. The major advantage is improved image quality, but dosimetry is a consideration as well, especially in children. Radiopharmaceutical Localization and Dosimetry Adrenal uptake occurs via a type I, energy-dependent, active amine transport mechanism. In addition to normal uptake in the adrenal medulla, the tracer localizes avidly in organs with rich adrenergic innervation, including the heart, salivary glands, and spleen. Normal uptake is seen in the liver, spleen, kidneys, liver, heart, and salivary glands. Variable activity has been reported in lungs, gallbladder, salivary glands, and nasal mucosa. Interfering drugs include tricyclic antidepressants, reserpine, guanethidine, certain antipsychotics, cocaine, and the alpha- and beta-blocker labetalol (Table 12-4). Prominent uptake in salivary glands, heart, liver, both adrenals (faint in posterior view, on right), and colon and bladder clearance. Whole body planar images (5 cm/sec) and limited spot views (500,000 counts or 10 minutes) can be done in adults. North American consensus guidelines for administered radiopharmaceutical activities in children and adolescents. Although I-123 can be imaged with a low-energy collimator, a small fraction of the photons (<3%) may be high energy (440-625 keV [2. For pheochromocytoma, posterior and anterior views of the abdomen are most important. Additional images from the pelvis to the base of the skull are indicated to detect extraadrenal pheochromocytoma and neuroblastomas. Clinical Applications Pheochromocytoma Pheochromocytoma is an uncommon catecholamine-secreting tumor derived from chromaffin cells. When these tumors arise outside of the adrenal gland, they are termed extraadrenal pheochromocytomas, or paragangliomas. Because of excessive catecholamine secretion, they can precipitate lifethreatening hypertension or cardiac arrhythmias. Ten percent of pheochromocytomas are bilateral, 10% are extraadrenal (paragangliomas), and 10% are malignant. Patient with poorly controlled hypertension and very elevated serum and urinary catecholamines. Focal increased uptake is noted in the region of the left adrenal consistent with a pheochromocytoma. The diagnosis of pheochromocytoma is suggested by detection of elevated blood or urinary catecholamines, although there are many other causes for these laboratory findings. If an adrenal mass is demonstrated in this setting, the diagnosis is inferred and further workup before surgery is often unnecessary. The sensitivity for detection is approximately 90% and specificity greater than 95%. Neuroblastoma Neuroblastoma is an embryonal malignancy of the sympathetic nervous system, typically occurring in children younger than 4 years of age. Seventy percent of tumors originate in the retroperitoneal region, from the adrenal or the abdominal sympathetic chain, and 20% occur in the chest, derived from the thoracic sympathetic chain.

Mating of male and female offspring as young adults (age not specified) resulted in significantly reduced mating success (females mated) and pregnancy rate at 1. Mating of female offspring with unexposed males as 1-year-old adults caused nearly a completely reduced number of mated females and zero pregnancy rate at 1. Female offspring were fed the same diets as the dams from weaning until 7 weeks of age, at which time they were mated with unexposed males. Fecundity (percentage of mated females that gave birth) and pup survival at ages 4 and 21 days were reduced in the F0 females at 7 mg/kg/day. There were no effects on fecundity or litter size in the F1 females, although all of their offspring died before 4 days of age at $0. Other effects included reduced in vitro fertilizing ability of the eggs and increased degenerated eggs in the F1 females at $0. Adult mice that were exposed to 130 mg/kg/day Aroclor 1254 in the diet for 14 days had no treatment-related changes in relative weights of the testes or preputial and vesicular accessory glands (Sanders et al. Similarly, no effects on testis weight, epididymis weight, or testicular histology or cytogenicity were found in adult rats that were treated with 50 mg/kg/day Aroclor 1254 by gavage for 7 days (Dikshith et al. Weanling F344 rats that were administered 25 mg/kg/day Aroclor 1254 by gavage for 15 weeks, however, had significant reductions in seminal vesicle and cauda epididymal weights, caudal epididymal sperm counts, and body weight gain (Gray et al. Fertility was markedly reduced in male offspring of Holtzman rats that were lactationally exposed to Aroclor 1254 (Sager 1983; Sager et al. Significant decreases in numbers of implants and embryos were observed at 8 mg/kg/day (21 and 29% lower than controls, respectively) and higher doses, and there was either a significant decrease or a decline in number and percent of normal fertilized eggs and eggs at the two- to four-cell blastocyte stages at $16 mg/kg/day. Measurements of absolute testes and ventral prostate weights in the F1 males (relative weights not determined) showed no changes except for increased testes weight in the Aroclor 1260 group. Mating performance and testicular histology were normal in four male minks that were fed 0. Aulerich and Ringer (1977) noted that long-term dietary exposure to Aroclor 1254 did not exert any apparent adverse effects on spermatogenesis in minks. A testicular biopsy on the affected animal showed marked hypoactivity of the seminiferous tubules characterized by an absence of mature spermatozoa and a predominance of Sertoli cells. Evaluation of sperm morphology and viability and the ability to fertilize unexposed females, performed during the first year of exposure, showed no effects in any of the four males. There were no effects on breeding performance in male minks in the 2-generation reproduction study of Lake Huron fish summarized in Section 3. No differences in the number of attempted or confirmed matings, or testicular volumes, were observed among the P1 and F1 generation males. Reproductive effects were evaluated in offspring of female Wistar rats that were treated with a single 0, 0. Mating of exposed male and female offspring as young adults (age not specified) resulted in significantly reduced mating success (females mated) and pregnancy rate at 1. Mating of exposed male offspring with unexposed females as 1-year-old adults resulted in a zero pregnancy rate at 1. Male F1 offspring were fed the same diets as the dams from weaning through 7 and 17 weeks of age, at which time, they were mated with unexposed females. Evaluation of reproductive ability of the F1 males showed no effects es as indicated by changes in fecundity (percentage of mated females that gave birth), litter size, sex ratio, or pup survival. Testes weights were increased in 7 mg/kg/day F1 males at 3 weeks, but not at 9 or 19 weeks of age. Additionally, although there were no effects on breeding, in vitro sperm-fertilizing ability was reduced in 7 mg/kg/day F1 males at 19 weeks, but not at 9 weeks of age. No effects on testis histology or serum testosterone concentration were observed, and reproductive capability was not evaluated. Effects on the testis were evaluated in adult male rats that were neonatally exposed to either Aroclor 1242 (.