Fukiat Ongseng

Non-Skeletal Accumulation of Bone Seeking Agents: Pelvis

HE GAMUT for extraosseous localization of Tc phosphate has expanded considerably since Heck published a total body list in the July 1980 issue (Semin Nucl Med 10:311). We discovered more than 20 additions in the pelvis alone. After falling out of bed, a 79-year-old female nursing home patient with a history of right hip surgery was found unconscious and distended. The patient was hospitalized and one day later a whole body scan was obtained to determine the extent of skeletal injury. The pelvic images (Fig 1) were more helpful in diagnosing bladder distention than sites of trauma. An immediate therapeutic catheterization followed by a diagnostic scintiphoto (Fig 2) uncovered several pelvic fractures. Activity in the low pelvis was initially felt to represent an incompletely drained bladder. Closer inspection suggested central photon deficiency, not the usual appearance of technetium homogeneously distributed in urine. A subsequent pelvic radiograph (Fig 3) demonstrated

Gallium scanning in the 'new' tuberculosis.

PURPOSE To evaluate the findings and usefulness of Ga-67 scanning in recent cases of tuberculosis (TB). MATERIALS AND METHODS The authors reviewed chest x-ray films and Ga-67 citrate scans of 52 patients with culture-confirmed infection caused by Mycobacterium tuberculosis treated after 1988. RESULTS Ga-67 scans were positive in every case, delineating upper lobe lung lesions in 6 patients, diffuse involvement or lower lobe disease in 34 patients, and intrathoracic adenopathy in 15 patients. Pulmonary parenchymal lesions were not detected on x-ray films in 3 patients, and nodal lesions were not apparent in 3 patients. In addition, in 6 patients cervical adenopathy was detected by Ga-67 scintigraphy; 4 underwent biopsy with culture confirmation. CONCLUSIONS Ga-67 scanning is more sensitive than routine chest radiography for detection of both TB parenchymal lung involvement and adenopathy. Ga-67 imaging facilitates the choice of biopsy sites by identifying accessible peripheral nodes. Typical patterns in recent cases of TB differ significantly from the upper lobe predilection of classical TB.

Detection of Gastroesophageal Reflux in the Head and Neck: The Role of Scintigraphy

Patients with gastroesophageal reflux (GER) present to the head and neck specialist with a myriad of nonspecific complaints that may be manifestations of pharyngoesophageal or upper airway involvement. Numerous diagnostic tests for GER have been used in the past with varying success. In the present study, gastroesophageal scintigraphy using 99mtechnetium-sulfur colloid was used to evaluate 28 patients with head and neck manifestations of GER. The role of gastroesophageal scintigraphy as an accurate and noninvasive method of detecting GER is discussed in the context of other current diagnostic modalities.

Gallium-67 imaging in candidal esophagitis.

Ga-67 scanning has been used to evaluate esophageal carcinoma. It has demonstrated candidal infection in other body sites and, in one previous case, in the esophagus. The authors present a case of diffuse esophageal uptake of Ga-67 in esophageal candidiasis.

Tc-99m sestamibi parathyroid gland scintigraphy: added value of Tc-99m pertechnetate thyroid imaging for increasing interpretation confidence and avoiding additional testing ☆

PURPOSE To evaluate the benefit of adding a pertechnetate parathyroid scan (dual-isotope imaging) in the interpretation of sestamibi dual-phase parathyroid scintigraphy. MATERIAL AND METHODS One hundred and sixteen dual Tc-99m sestamibi (MIBI) and Tc-99m pertechnetate subtraction parathyroid studies, performed between January 2000 and February 2006, were retrospectively reviewed. Dual-phase technetium sestamibi examinations were initially interpreted, with blinding to the technetium pertechnetate findings. Subsequently, technetium pertechnetate scan findings were added, and changes in interpretation were recorded. RESULTS By adding Tc-99m pertechnetate imaging, the interpretation of 17 scans (17/116=14.6%) was substantially altered. This included 5 scans (4%) that changed from negative to positive and 9 scans (8%) that changed from equivocal to positive, excluding ectopic tissue and directing minimally invasive surgery, without the need for further imaging, such as ultrasound, in 12% of cases. One examination changed from positive to negative. In addition, 2 scans changed from equivocal to negative, necessitating further preoperative imaging for the evaluation of additional pathology such as thyroid nodules and lymph nodes and the consideration of hyperplasia. Among the remaining 99 patients, Tc-99m pertechnetate scans may also have contributed to the diagnosis in the 66 positive Tc-99m MIBI scans by increasing confidence in the interpretation and obviating additional imaging. Ten cases remained equivocal. CONCLUSION By adding Tc-99m pertechnetate imaging, scan interpretation was changed in 14.6% of cases, and interpretation confidence was enhanced in all but 10 remaining equivocal cases. The addition of a dual-isotope subtraction also eliminated the need for additional testing, such as ultrasound, in 12% of our cases. Increased confidence in interpretation that comes with dual-isotope subtraction may come at the cost of slight lengthening of imaging time but likely simplifies preoperative localization and decreases intraoperative time for many patients with primary hyperparathyroidism.

Scintigraphic pattern of pneumothorax complicating pneumocystis carinii pneumonia in patients with AIDS

Spontaneous pneumothorax is a serious though infrequently reported pulmonary complication of AIDS. An unsuspected lung collapse was discovered via gallium scintigraphy for the study of Pneumocystis carinii pneumonia. Neither the pneumonia nor the pneumothorax were apparent on the most recent chest roentgenogram. In evaluating gallium images during the work-up of AIDS patients with associated pulmonary pathology, the possible complication of lung collapse should be considered. If pneumothorax js suspected on gallium imaging, a chest roentgenogram in expiration must be obtained for prompt delineation of this serious, yet correctable, condition.

Hepatobiliary rim sign: new implications for acute and complicated cholecystitis.

PurposeThe role of a ‘rim sign’ in increasing specificity for acute cholecystitis and sensitivity for complicated acute cholecystitis has been substantiated in many small retrospective studies. We sought to corroborate this correlation in a large population, as we have encountered doubt among surgeons about the emergent implications of this sign. MethodsWe performed a small pilot interobserver reliability test with five nuclear medicine physicians from outside institutions. A total of 2881 consecutive hepatobiliary scans performed over 12 years for evaluation of acute cholecystitis were retrospectively reviewed. Available pathological (reference standard) and surgical reports were reviewed for all cases of acute cholecystitis (on scintigraphy) with a rim sign and for an equivalent set without a rim sign. ResultsThere was no statistically significant interobserver agreement on the presence of a rim sign.There was a 32.4% incidence of acute cholecystitis, based on scintigraphy, and a 10.1% incidence of rim signs. Of 63 pathologic specimens from rim-sign-positive cases, 19 (30.2%) showed acute cholecystitis and 44 (69.8%) showed chronic cholecystitis. Six (9.5%) cases were complicated.Among 55 pathologic specimens from the acute scintigraphy cases without a rim sign, 21 (38.2%) showed acute cholecystitis and 34 (61.8%) showed chronic cholecystitis. There were eight (14.5%) complicated cases. ConclusionThere was no interobserver reliability in the identification of a rim sign. There was almost no difference in the incidence of pathologically acute, chronic, or complicated acute cholecystitis among scintigraphically acute cases with or without a rim sign, approximately two-thirds to three-quarters of which were chronic on pathological evaluation.

What Is the Relationship of Low Back Pain to Signs of Abnormal Skeletal Metabolism Detected by Bone Scans

BACKGROUND In approximately 80-85% of patients with chronic nonspecific low back pain (NSLBP), a precise pathoanatomical diagnosis cannot be identified. Mechanisms of bone nociception may contribute to NSLBP. OBJECTIVE To determine whether findings on bone scans, which provide a pathophysiological picture of functional activity, are associated with self-reports of NSLBP intensity. DESIGN A cross-sectional study of the relationship of self-reported chronic NSLBP intensity to the uptake of radiolabeled technetium-99m-methylene diphosphonate in the lumbosacral area. STUDY PARTICIPANTS Patients referred for bone scans who were at least 18 years old. OUTCOME MEASURES Subject reports of pain intensity and intensity of uptake of radiolabeled technetium-99m-methylene diphosphonate in the lumbosacral area. RESULTS Among subjects who were 65 years or younger, the age-adjusted worst pain intensity accounted for 45% of the variability in the amount of tracer uptake (r = 0.67, P = 0.0006). The association was not significant for those older than 65 years. CONCLUSION Further studies should be conducted on possible mechanisms relating bone nociception to chronic NSLBP in individuals who are 65 years or younger.

The offensive wrist.

Fencing between injection of Tc-99m MDP and imaging resulted in a diffuse increase in radioactivity in the asymptomatic wrist of a right-handed fencer. Repeat study two weeks later showed normal distribution of radiopharmaceutical. At that time, the athlete was fenced into the patient waiting area between injection and scan.