Use Of Scintigraphy Research Articles

Use of Scintigraphy for Diagnosis of Equine Paranasal Sinus Disorders

To describe and analyze subjective and objective scintigraphic findings in horses with paranasal sinus disorders. Horses with suspected disorders of the paranasal sinuses or cheek teeth (n = 48) and control horses (n = 30). 99Technetium-methylenediphosphate (99Tc-MDP; 7500 MBq) was administered for scintigraphic examination of the skull. Abnormal patterns of increased radionuclide uptake (IRU) were identified and subjectively described. Scintigrams and radiographs were blindly assessed by 2 clinicians and the accuracy of the imaging modalities was compared. Objective analysis was performed by comparing regions of interest (ROI) drawn over areas of abnormal IRU to the equivalent area on the unaffected side using the Mann-Whitney test. An ROI ratio (affected:non-affected sides) was also calculated for each lesion. Twenty-eight horses were diagnosed with primary (15) or secondary (13) sinusitis. Nine primary sinusitis cases had focal area(s) of moderate or marked IRU in addition to a more diffuse uptake in the affected sinus(es). kappa was marginally higher for scintigraphic assessment of paranasal sinus disorders than for radiographic assessment. There were significant differences in mean counts/pixel in ROI drawn on the affected side compared with the non-affected side. There was considerable overlap between the magnitudes of ROI ratios found with many different disorders. Scintigraphy can be useful for differentiation of sinusitis of dental origin from other causes of sinusitis. Quantitative analysis of scintigrams is not reliable for identification of particular disorders. Focal areas of moderate or marked IRU may be observed with primary sinusitis. Careful 3-dimensional localization of the lesion, along with consideration of other clinical and diagnostic findings should be performed to prevent false-positive diagnoses of periapical infection in such instances.

Measurement of gastric emptying by octanoate metabolism

Since its introduction just over 10 years ago, there have been a number of studies that have used the octanoate breath test to assess gastric emptying. Although use of the method is on the increase (the number of gastric emptying studies published on PubMed using the octanoate breath test has doubled between the periods 1997-2000 and 2001-2004 compared with a drop of approximately 20% in the use of scintigraphy over the same periods), the methodology has not achieved universal acceptance, primarily because it can provide results comparable to established techniques only indirectly. Recent methods for overcoming this difficulty are reviewed, including modified methods for breath test interpretation and the application of the related saliva test. The latter promises to be useful as a non-invasive proxy for established techniques, such as scintigraphy, for further validation of the breath test. Recent applications of octanoate-based methods are briefly considered. A novel approach detailed in this review for breath test interpretation, where the bicarbonate pool is modelled as a single compartment, could prove useful for obtaining breath test gastric emptying parameters that are directly comparable with those obtained from the gold standard, gamma scintigraphy. In combination with the saliva test, this could add credence to use of the octanoate breath test as a clinically accepted diagnostic tool, in addition to its potential in research.

Use of Scintigraphy for the Diagnosis of Apical Infection of Equine Cheek Teeth

Scintigraphy with 99m Technetium Methyldiphosphate ( 99m Tc-MDP) can detect changes in bone which precede radiographic changes, and this makes it a very useful imaging modality for the diagnosis of early periapical infection of the equine cheek teeth, where the results of radiography may be equivocal. It is a particularly useful technique for the differentiation of dental sinusitis from other causes of sinusitis. Bone phase images acquired 2 to 4 hours postinjection give the most useful information for the evaluation of dental and sino-nasal lesions. Images should be acquired in sedated horses using dynamic studies which are then motion corrected. Left and right lateral, dorsal, and ventral views are usually sufficient to image the equine skull fully; however, oblique views may occasionally be useful for lesion localization. Periapical infections of the cheek teeth typically result in focal and intense increased radionuclide uptake (IRU) located over the apical region of the affected tooth. In contrast, most cases of primary sinusitis show more diffuse and less marked IRU over the affected region(s). However, some cases of primary sinusitis do exhibit focal areas of moderate to marked IRU, and care should be taken to try and differentiate these from periapical infections by three-dimensional lesion localization.

Imaging of regional lymph node metastases with 99mTc-depreotide in patients with lung cancer

The aim of this study was to evaluate the clinical usefulness of scintigraphy with 99mTc-depreotide in the assessment of loco-regional nodal spread in patients with suspected lung cancer in comparison with computed tomography (CT). Eighty-six patients were investigated with single-photon emission computed tomography (SPECT) of the thorax after i.v. injection of 740 MBq 99mTc-depreotide. The results were evaluated in conjunction with a thoracic CT scan in all 86 patients with 204 lymph node stations. The scintigraphic results were correlated with cytological (38), histological (20) or clinical-radiological (146) findings and compared with CT. The quantitative evaluation of depreotide uptake was performed on 48 cytologically or histologically verified nodal stations from 28 patients by SPECT using region of interest analysis with four different reference regions. 99mTc-depreotide scintigraphy for all 204 investigated lymph node stations had a sensitivity of 99% and a negative predictive value of 98% in determining lymph node involvement. Scintigraphy and CT showed the same level of accuracy, 76.4%. CT findings had a higher positive predictive value but a lower negative predictive value compared to 99mTc-depreotide scintigraphy. The quantitative evaluation of depreotide uptake in lymph nodes using vertebra as a reference region showed that a cut-off level of 0.56 excludes malignant involvement of lymph nodes, while a cut-off level of 1.66 excludes benign disease in lymph nodes. About 73% of all investigated lymph node stations showed uptake values between these cut-off levels. Absence of 99mTc-depreotide uptake on scintigraphic imaging can exclude regional lymph node involvement with a high degree of probability and may be useful in clinical practice. The quantitative evaluation of depreotide uptake in regional lymph nodes did not increase the diagnostic accuracy of the method in general but did elucidate the lymph node status in some patients.

Meckel’s Diverticulitis: Diagnosis With Computed Tomography and Tc-99m Pertechnetate Scintigraphy

A diagnosis of Meckel's diverticulitis was reached preoperatively in a 7-year-old boy with severe left-sided abdominal pain and fever after technetium-99m pertechnetate scintigraphy indicated the presence of heterotopic gastric mucosa in a left lower quadrant mass that had been shown by computed tomography. The case illustrates the use of scintigraphy in confirming a suspected diagnosis of Meckel's diverticulitis and is an example of a Meckel's diverticulum in the lower left abdomen rather than the more common locations of the lower right and midabdomen.

The use of scintigraphy to identify and localize the mammary sentinel lymph nodes in female dogs: prognostic value

The use of scintigraphy to identify and localize the mammary sentinel lymph nodes in female dogs: prognostic value

Optimization of the Gamma Probe-Guided Parathyroidectomy

The objective of this study was to determine the patient-specific optimal time to surgery preoperatively to improve operative success in gamma probe-guided parathyroid localization. Fifteen patients with hyperparathyroidism underwent a double-phase Tc99m-MIBI (15-20 mCi) parathyroid scintigraphy to study the Tc99m-MIBI clearance kinetics from parathyroid and thyroid glands and to determine the time point at which the optimal target-to-background ratio was achieved. Optimal time to surgery was determined on the basis of the time at which the target-to-background ratio was maximal. On the day of surgery the patients received the same dose of Tc99m-MIBI and were taken to the operating room at the time of optimal target-to-background ratio. A four-gland exploration was performed with identification and excision of hot lesions using a gamma probe. Ex vivo lesion-to-background ratios were determined. Histopathologic confirmation of a successful parathyroidectomy was obtained intraoperatively by frozen section. The total operative time and the time to localize and excise the parathyroid glands were recorded. The mean surgery time was compared with that of previous parathyroidectomies performed by the same surgical team without use of preoperative scintigraphy and intraoperative gamma probe. Scintigraphy correctly localized parathyroid pathology in 12 of 15 (80%) patients. Intraoperative gamma probe was successful in 15 of 15 (100%). The optimal time to surgery was found to be different for each patient, and the mean time was calculated as 136 +/- 43 minutes. Mean surgery time for the excision of parathyroid gland was 91 +/- 46 minutes, which was significantly shorter than previous four-gland exploration without use of scintigraphy and gamma probe (160 +/- 61 minutes; t = 3.021, P = 0.007). The mean ex vivo lesion-to-background gamma probe count ratio of abnormal parathyroid glands (77.35) was found to be significantly higher than that of all other lesions with abnormal Tc99m-MIBI uptake (5.05) (U = 10.5, P < 0.0001). Optimal target-to-background ratio is essential for the success of gamma probe-guided parathyroidectomy. This ratio was highly variable among the patients in this study. Individualization of the best surgical exploration time after Tc99m-MIBI injection will improve the surgical success of this operation.

Use of scintigraphy for assessment of fracture healing and early diagnosis of osteomyelitis following fracture repair in rabbits.

To evaluate use of technetium Tc 99m disodium hydroxymethylene diphosphonate (99m-Tc-HDP) for assessing fracture healing and 99m-Tc-HDP and technetium Tc 99m ciprofloxacin (99m-Tc-CIPRO) for early diagnosis of osteomyelitis in rabbits. 32 skeletally mature New Zealand White rabbits. A femoral fracture defect stabilized with bone plates and cortical screws was used. Scintigraphy was performed 4, 8, 12, and 16 weeks after surgery. The 99m-Tc-CIPRO scan was performed 48 hours after the 99m-Tc-HDP scan. The uptake ratio of the experimental limb to the normal limb was calculated by use of multiple regions of interest. Results of radiography performed to determine external callus and lysis grade and percentage defect ossification at 16 weeks were compared with scintigraphy results. Infected fractures had a higher uptake ratio for 99m-Tc-HDP and 99m-Tc-CIPRO than noninfected fractures. Infected fractures could be differentiated from noninfected fractures late in healing by use of 99m-Tc-HDP. Although 99m-Tc-CIPRO was better than 99m-Tc-HDP for identifying infection, there was a high incidence of false positive and negative results with 99m-Tc-CIPRO. There was an association between 99m-Tc-HDP uptake ratio and callus formation and a good correlation between 99m-Tc-HDP uptake ratio and defect ossification after 4 weeks. 99m-Tc-HDP and 99m-Tc-CIPRO may be useful for diagnosing osteomyelitis late in fracture healing; however, false positive and false negative results occur. Technetium Tc 99m disodium hydroxymethylene diphosphonate may be useful for evaluating fracture healing.

Oesophageal scintigraphy for the investigation of dysphagia: in ans out of favour - underused when available.

Oesophageal scintigraphy has been used for more than 25 years and allows quantifiable, safe, rapid, non-invasive and well-tolerated assessment of oesophageal transit time and function. As technology improves, more complex image analysis is becoming possible. Many studies have addressed its usefulness in assessing oesophageal dysmotility using manometry as the gold standard: this literature is reviewed with reference to both the sensitivity and the specificity of the test as well as its application and effectiveness in various disease states. The use of scintigraphy in oesophageal cancer is specifically addressed - including in co-existing dysmotility.

(99m)Technetium pentavalent dimercaptosuccinic acid scintigraphy in the follow-up of clinically nonfunctioning pituitary adenomas after radiotherapy.

It is still difficult to differentiate pituitary adenoma remnants from postradiotherapy fibrosis by computed tomography (CT) or magnetic resonance imaging (MRI), especially in patients with clinically nonfunctioning pituitary adenomas (NFA), lacking circulating markers to follow disease progression or cure. We investigated the usefulness of scintigraphy with technetium-99m pentavalent dimercaptosuccinic acid [(99m)Tc(V)DMSA], shown previously to detect most pituitary GH- and PRL-secreting adenomas and NFA, with tumour-to-background ratios (T/B) as high as 25-fold. Eighteen patients with NFA (study group), 10 patients with GH- and three patients with PRL-secreting adenomas (control group), all of whom had undergone previous surgery. The study was an open longitudinal design. Pituitary CT/MRI and (99m)Tc(V)DMSA scintigraphy was performed before and 1, 3 and 5 years after conventional radiotherapy. Tumour size was measured as maximal diameter of the residual lesion, while uptake of (99m)Tc(V)DMSA was measured as a T/B ratio. At study entry, pituitary (99m)Tc(V)DMSA uptake was found in 13 NFA (72.2%), seven GH-secreting (70%) and all PRL-secreting adenomas; remnant tumour was documented by CT/MRI in all 31 patients. Maximal remnant diameter was significantly higher in patients with positive (13.3 +/- 0.9 mm) than in those with negative scintigraphy (7.0 +/- 0.3 mm, P < 0.001). During the 5-year follow-up postradiotherapy, a significant decrease in (99m)Tc(V)DMSA uptake (9.7 +/- 0.8 vs. 3.2 +/- 0.5, P < 0.0001) occurred in all but three patients. Two NFA patients died of tumour invasion 19 and 36 months after radiotherapy and one acromegalic patient had no change in his hormone levels. In the eight negative patients (five NFA and three GH), scintigraphy remained negative throughout follow-up. A remarkable shrinkage of the remnant tumour was observed in both the patients with negative (from 7.0 +/- 0.3 to 1.9 +/- 0.6 mm, P < 0.001) and in those with positive scintigraphy (from 13.3 +/- 0.9 to 7.3 +/- 0.6 mm, P < 0.001). At the end of the study, CT/MRI showed evident remnant tumour in 13 of 16 NFA (81.2%), nine GH-secreting (90%) and all three prolactinomas (100%), while the scintigraphy was negative (T/B < 1) or faintly positive (T/B 1-2) in eight of 16 NFA (50%), five GH-secreting (50%) and one prolactinoma (33.3%). Functional imaging of pituitary remnant adenomas (> 10 mm in size) by (99m)Tc(V)DMSA depicts viable pituitary adenoma remnants. This approach may be of clinical value in patients with clinically nonfunctioning adenomas to monitor the effects of radiotherapy.

Usefulness of scintigraphy with technetium-99m galactosyl human serum albumin in prediction of prognosis of primary biliary cirrhosis

Prediction of survival of patients with primary biliary cirrhosis (PBC) has been based on results of blood tests and other indices of clinical condition, which may be affected by treatment. We earlier evaluated hepatic receptor imaging with 99mTc galactosyl human serum albumin as an alternative method for prediction of survival. To evaluate whether this method is useful for this purpose, we examined the cumulative survival rate of patients with PBC since their first examination by this method. The subjects were 60 patients with PBC, 10 healthy subjects, 65 patients with chronic hepatitis, and 196 patients with cirrhosis. Computer acquisition of gamma-camera data was started just before the injection of 99mTc galactosyl human serum albumin and was stopped 20 min later. As indices of hepatic functional reserve, the receptor index and the index of blood clearance were calculated. Among the patients with PBC, the receptor index was lower in those with stage IV than in those with stages I, II, or III, and the index of blood clearance was higher in patients with stage IV than in those with stages I, II, or III. On the basis of the receptor index, the patients with PBC were divided arbitrarily into two groups of roughly equal size: group A with a receptor index of ≥0.94, and group B with index <0.94. On the basis of the index of blood clearance, the patients were also divided into two groups of roughly equal size: group C with an index of blood clearance of <0.52, and group D with index ≥0.52. Cumulative survival rates were significantly lower in group B than in group A ( P=0.026), and lower in group D than in group C ( P=0.005). Regression analysis showed the index of blood clearance to be significantly related to survival. In conclusion, hepatic receptor imaging with 99mTc galactosyl human serum albumin can be used to noninvasively evaluate the hepatic functional reserve of patients with PBC and is useful clinically in establishing their prognosis.

Evaluation of acetaminophen absorption in horses with experimentally induced delayed gastric emptying

To evaluate the correlation between the half-time of liquid-phase gastric emptying (T50) determined by use of nuclear scintigraphy, using technetiumTc 99m pentetate, and absorption variables of orally administered acetaminophen in horses with experimentally delayed gastric emptying. 6 mature horses. Delayed gastric emptying was induced by IV injection of atropine sulfate. Twenty minutes later, acetaminophen and technetium Tc 99m pentetate were administered simultaneously via nasogastric tube. Serial lateral images of the stomach region were obtained, using a gamma camera. Power exponential curves were used for estimation of T50 and modified R2 values for estimation of goodness-of-fit of the data. Serial serum samples were obtained, and acetaminophen concentration was determined, using fluorescence polarization immunoassay. Maximum serum concentration (Cmax), time to reach maximum serum concentration (Tmax), area under the curve for 480 minutes, and the appearance rate constant were determined, using a parameter estimation program. Correlations were calculated, using a Spearman rank correlation coefficient. A significant correlation was detected between T50 determined by use of scintigraphy and Tmax determined by use of acetaminophen absorption. Correlation between T50 and other absorption variables of acetaminophen was not significant. The acetaminophen absorption method was a valid technique in this model of delayed gastric emptying in horses. The method may be a valuable tool for use in research as well as in clinical evaluation of gastric emptying in horses.

Échographie doppler énergie et pyélonéphrite aiguë de l’enfant : comparaison avec la scintigraphie au DMSA-Tc

Acute pyelonephritis is a common infection in children. The clinical and biological diagnosis is still sometimes difficult. For most authors, Technecium 99m dimercaptosuccinic acid scintigraphy is considered as the gold standard tool for diagnosis but it is invasive and expensive. The aim of our study was to compare the sensitivity and the specificity of B-mode sonography and power doppler to DMSA-Tc scintigraphy in acute pyelonephritis. Patients and methods. – Forty-nine children were enrolled in this study with suspicion of pyelonephritis. All infants underwent doppler sonography and scintigraphy within 48 hours after their hospitalization. Doppler sonography criteria were increased kidney size, thickness of sinus wall, vascular defect, and various echogenicity of the kidneys (focal or diffuse hyperechogenicity or focal hypo-echogenicity). Results. – Among 28 children with a positive scintigraphy, 15 had a positive doppler sonography (sensitivity 54 %) and 13 had a negative doppler sonography. Among 21 children with a negative scintigraphy, 20 had a negative doppler sonography (specificity 95 %) and one had a positive doppler sonography. Conclusion. – In clinically suspected acute pyelonephritis, doppler sonography has a high specificity. A positive doppler sonography should avoid the use of scintigraphy.

Diagnosis, characterisation and evaluation of treatment response of frostbite using pertechnetate scintigraphy: a prospective study.

No large prospective study is available on use of a radionuclide method to assess frostbite and its response to conservative treatment. Recently, a large retrospective study using two-phase bone scintigraphy suggested that non-uptake (or low uptake) in frostbite lesions in the blood pool or bone phase had a strong correlation with the subsequent need for amputation. In the present study, we performed early blood pool scintigraphy with technetium-99m pertechnetate in 20 patients (10-180 days after frostbite injury; 71 clinical lesions) referred for a topical treatment protocol for mild to moderately severe frostbite, and in 22 asymptomatic controls. The aims of the study were to define the "normal" microcirculation of the hands and feet, to characterise the appearances of frostbite lesions on scintigraphy and correlate these with the clinical presentation, and to evaluate the usefulness of scintigraphy for assessing the treatment response. Six patients were "fresh", 12 had been undergoing conservative treatment (topical homeopathic) for several weeks and two had permanent fibrotic hand phalanges. Nine patients on treatment underwent serial scintigraphy a total of 22 times. Eleven patients were imaged only once, including the two with permanent fixed defects. Three distinct physiological microcirculation patterns were evident in control hands or feet: right- or left-handedness (seven subjects), subclinical inflammatory foci correlating with callosity or pressure points (36 lesions) and distinctly increased pooling of radiotracer at the thenar or hypothenar region (eight subjects). In frostbite patients, 128 lesions (48 inflammatory, 80 ischaemic) were seen on the scan. This number included all 71 lesions identified clinically, the rest being subclinical. Subclinical frostbite lesion as an entity has not been described previously. Microvasculature of normal muscle groups (in the hands, elbow or feet) was shown on scintigraphy to improve after topical treatment. The treatment resulted in improved or normalised perfusion scan in 25 of 45 ischaemic segments with matching clinical improvement, and reduction or normalisation of uptake in inflammatory lesions (n=30). The data confirm the vasodilator and anti-inflammatory action of the topical preparation, and the sensitivity of the radionuclide method in monitoring treatment response. In contrast to the previous findings that non-uptake on a scan performed 2 or more weeks after exposure correlates with the need for amputation, none of the 80 ischaemic lesions in our series required amputation while 60% showed improvement or normalisation in microvascular blood flow even though they were 10-180 days old. Our findings suggest that moderate to severe frostbite lesion can be classified as having infarcted, ischaemic or hibernating (viable) tissue, similar to the classification employed when using myocardial scintigraphy. Absence of uptake even after the initial 10 days does not necessarily indicate infarction and the need for amputation as many such lesions retain potential for vasodilation and recovery.

The use of scintigraphy to demonstrate the rapid esophageal transit of the oval film-coated placebo risedronate tablet compared to a round uncoated placebo tablet when administered with minimal volumes of water

As our population ages, and the consumption of pharmaceutical products rises, the incidence of solid oral dosage forms lodging in the esophagus is likely to increase and may be formulation dependent. The aim of this study was to compare the esophageal transit of the commercial film-coated risedronate tablet and a round uncoated tablet resembling the alendronate 10 mg tablet which is reported to cause esophagitis if ingested with little to no water. Water volumes of 30 ml and 50 ml were selected as these volumes can detect formulations prone to esophageal adhesion and a habits and practice study showed that these volumes are within the range preferred by women (7–385 ml). A total of 28 healthy postmenopausal women completed the four-way crossover scintigraphy study. For both volumes of water, the film-coated placebo risedronate tablet had a statistically significant faster esophageal transit time than the uncoated placebo tablet ( P=0.002 for 30 ml water and P<0.001 for 50 ml water). Among those taking the round, flat, uncoated tablet, five subjects had esophageal stasis (transit >20 s) and in three subjects the tablet remained in the esophagus at the end of the 10-min imaging period. No stasis was observed for the oval film-coated placebo risedronate tablet. This study demonstrates that tablet size, shape and coating are pharmaceutical parameters which can be controlled to minimize esophageal contact of a dosage form with esophageal tissue.

Symptomatic and Asymptomatic Accessory Navicular Bones: Findings of Tc-99m MDP Bone Scintigraphy

AIM: The accuracy of bone scintigraphy in diagnosing symptomatic accessory navicular bones has not been well studied. We conducted a retrospective study to explore the results and use of scintigraphy in symptomatic and asymptomatic accessory navicular bones.MATERIALS AND METHODS: Thirteen patients with a total of 13 symptomatic and 10 asymptomatic accessory navicular bones were included in the study. We used a scoring system to grade the scintigraphic abnormalities. The patients’ symptoms and scintigraphic findings were recorded.RESULTS: Though focally increased radiopharmaceutical uptake was observed in all symptomatic accessory naviculars, half of the asymptomatic accessory navicular bones had the same manifestations. The scoring system was of no value in differentiating symptomatic from asymptomatic accessory navicular bones.CONCLUSION: Bone scintigraphy is a sensitive but not a specific tool for diagnosing a symptomatic accessory navicular.Chiu, N.-T. (2000). Clinical Radiology55, 353–355.

Use of scintigraphy in the diagnosis of dental disease in four horses

Use of scintigraphy in the diagnosis of dental disease in four horses

Determination of solid- and liquid-phase gastric emptying half times in cats by use of nuclear scintigraphy

Abstract Objective To use nuclear scintigraphy to establish a range of gastric emptying half times (t1/2) following a liquid or solid meal in nonsedated cats. Animals 12 clinically normal 3-year-old domestic shorthair cats. Procedure A test meal of 75 g of scrambled eggs labeled with technetium Tc 99m tin colloid was fed to 10 of the cats, and solid-phase gastric emptying t1/2 were determined by use of nuclear scintigraphy. In a separate experiment, 8 of these cats plus an additional 2 cats were fed 18 ml (n = 5) or 36 ml (n = 5) of a nutrient liquid meal labeled with technetium Tc 99m pentetate. Liquid-phase gastric emptying t1/2 then were determined by use of scintigraphy. Results Solid-phase gastric emptying t1/2 were between 210 and 769 minutes (median, 330 minutes). Median liquid-phase gastric emptying t1/2 after ingestion of 18 or 36 ml of the test meal were 67 minutes (range, 60 to 96 minutes) and 117 minutes (range, 101 to 170 minutes), respectively. The median t1/2 determined for cats receiving 18 ml of the radiolabeled liquid was significantly less than that determined for cats receiving 36 ml of the test meal. Conclusions and Clinical Relevance The protocol was tolerated by nonsedated cats. Solid-phase gastric emptying t1/2 were prolonged, compared with liquid-phase t1/2, and a major factor governing the emptying rate of liquids was the volume consumed. Nuclear scintigraphy may prove useful in assessing gastric motility disorders in cats. (Am J Vet Res 1999;60:1222–1226)

Protocols for the preoperative selection of palpable thyroid nodules: review and progress.

Modern protocols for the management of patients with palpable thyroid nodules agree that fine-needle aspiration is the first examination to be performed. However, they differ very much in the role attributed to scintigraphy and ultrasound examinations. In some protocols, these two techniques are not considered, whereas in others they are recommended at the end of the diagnostic workup to select for surgery those nodules with nondiagnostic or suspect fine-needle aspiration biopsy results. We report original data and literature showing that such use of scintigraphy and ultrasonography is not cost effective. Furthermore, we report original data showing that large-needle aspiration biopsy can be used to select for surgery those nodules with nondiagnostic or suspect results after fine-needle aspiration. Consequently, we suggest a new protocol for the preoperative selection of palpable thyroid nodules.

Use of scintigraphy with 99mtechnetium galactosyl human serum albumin for staging of primary biliary cirrhosis and assessment of prognosis.

Conventional models for prediction of survival in patients with primary biliary cirrhosis (PBC) are based on the results of blood tests and on the clinical condition, which may be affected by treatment. We evaluated the usefulness of hepatic receptor imaging with [99mtechnetium]-diethylenetriaminepentaacetic acid galactosyl human serum albumin (GSA) for the staging and prognosis of PBC without the need for reference to laboratory test results. The subjects were 45 patients with PBC, 10 healthy subjects, 62 patients with chronic hepatitis and 144 patients with cirrhosis. Computer acquisition of gamma-camera data was started just before the injection of 185 MBq [99mTc]-GSA and was stopped 20 min later. Time-activity curves were generated from regions of interest (ROI) for the heart and liver. A receptor index was calculated by dividing the radioactivity of the liver ROI by that of the liver-plus-heart ROI 15 min after the injection. An index of blood clearance was calculated by dividing the radioactivity of the heart ROI 15 min after the injection by that of the heart ROI 3 min after the injection. The median receptor index was higher in patients with PBC than in those with cirrhosis. Among patients with PBC, the receptor index was lower in those with stage IV disease than in those in stages I, II or III. The index of blood clearance was lower in patients with PBC than in those with cirrhosis. Among patients with PBC, the index of blood clearance was higher in those with stage IV disease than in those in stages I, II or III. The receptor index was correlated significantly both to the risk score of the Mayo model and to the prognostic index of the Japanese model. The index of blood clearance was also correlated significantly to this score and prognostic index. Hepatic receptor imaging with [99mTc]-GSA is useful for the evaluation of hepatic functional reserve, staging of PBC and assessment of prognosis.