Search

Key Points Question Can the favorable properties of an ultrasmall fluorescent core-shell silica nanoparticle aid real-time image-guided detection, localization, and surgical management of sentinel lymph nodes (SLNs) in patients with head and neck melanoma? Findings In this nonrandomized clinical trial of 24 patients, real-time, particle-based fluorescence imaging of SLNs was feasible and safe at the microdosing level and enabled deep-tissue nodal detection. There was high concordance in identifying nodes between preoperative lymphoscintigraphy and particle-based fluorescence-guided biopsy. Meaning The findings of this study suggest that ultrabright, optical contrast–conferring particles for SLN identification hold promise for overcoming current probe limitations and improving surgical outcomes., This nonrandomized clinical trial evaluates whether an ultrasmall, molecularly targeted core-shell silica nanoparticle can safely and reliably identify optically avid SLNs in head and neck melanoma during fluorescence-guided biopsy., Importance Sentinel lymph node (SLN) mapping agents approved for current surgical practice lack sufficient brightness and target specificity for high-contrast, sensitive nodal visualization. Objective To evaluate whether an ultrasmall, molecularly targeted core-shell silica nanoparticle (Cornell prime dots) can safely and reliably identify optically avid SLNs in head and neck melanoma during fluorescence-guided biopsy. Design, Setting, and Participants This nonrandomized clinical trial enrolled patients aged 18 years or older with histologically confirmed melanoma in whom SLN mapping was indicated. Exclusion criteria included known pregnancy, breast-feeding, or medical illness unrelated to the tumor. The trial was conducted between February 2015 and March 2018 at Memorial Sloan Kettering Cancer Center, with postoperative follow-up of 2 years. Data analysis was conducted from February 2015 to March 2018. Interventions Patients received standard-of-care technetium Tc 99m sulfur colloid followed by a microdose administration of integrin-targeting, dye-encapsulated nanoparticles, surface modified with polyethylene glycol chains and cyclic arginine-glycine–aspartic acid–tyrosine peptides (cRGDY-PEG-Cy5.5-nanoparticles) intradermally. Main Outcomes and Measures The primary end points were safety, procedural feasibility, lowest particle dose and volume for maximizing nodal fluorescence signal, and proportion of nodes identified by technetium Tc 99m sulfur colloid that were optically visualized by cRGDY-PEG-Cy5.5-nanoparticles. Secondary end points included proportion of patients in whom the surgical approach or extent of dissection was altered because of nodal visualization. Results Of 24 consecutive patients enrolled (median [interquartile range] age, 64 [51-71] years), 18 (75%) were men. In 24 surgical procedures, 40 SLNs were excised. Preoperative localization of SLNs with technetium Tc 99m sulfur colloid was followed by particle dose-escalation studies, yielding optimized doses and volumes of 2 nmol and 0.4 mL, respectively, and maximum SLN signal-to-background ratios of 40. No adverse events were observed. The concordance rate of evaluable SLNs by technetium Tc 99m sulfur colloid and cRGDY-PEG-Cy5.5-nanoparticles was 90% (95% CI, 74%-98%), 5 of which were metastatic. Ultrabright nanoparticle fluorescence enabled high-sensitivity SLN visualization (including difficult-to-access anatomic sites), deep tissue imaging, and, in some instances, detection through intact skin, thereby facilitating intraoperative identification without extensive dissection of adjacent normal tissue or nerves. Conclusions and Relevance This study found that nanoparticle-based fluorescence-guided SLN biopsy in head and neck melanoma was feasible and safe. This technology holds promise for improving lymphatic mapping and SLN biopsy procedures, while potentially mitigating procedural risks. This study serves as a first step toward developing new multimodal approaches for perioperative care. Trial Registration ClinicalTrials.gov Identifier: NCT02106598

Continuous ambulatory peritoneal dialysis is a convenient alternate form of treatment in patients receiving hemodialysis for renal failure. Sometimes during the procedure, patients may develop scrotal swelling because of patent processus vaginalis. The diagnostic utility of the peritoneal scintigraphy, an infrequently performed nuclear medicine scan to identify peritoneoscrotal communication, has been reported by many authors. Most of the previous case reports in the literature demonstrated unilateral peritoneoscrotal communication. We present an interesting Tc-sulfur colloid peritoneal scintigraphic image finding of bilateral peritoneoscrotal communication in a 67-year-old man who developed scrotal swelling while undergoing continuous ambulatory peritoneal dialysis.

Significant variability in the pharmacokinetics and pharmacodynamics of PEGylated liposomal doxorubicin (PLD) exists. PLD undergoes clearance via the mononuclear phagocyte system (MPS). Technetium Tc 99m sulfur colloid (TSC) is approved for imaging MPS cells. We investigated TSC as a phenotypic probe of PLD pharmacokinetics and pharmacodynamics in women with epithelial ovarian cancer. TSC 10 mCi IVP was administered and followed by dynamic planar and SPECT/CT imaging and blood pharmacokinetics sampling. PLD 30–40 mg/m2 IV was administered with or without carboplatin, followed by plasma pharmacokinetics sampling. There was a linear relationship between TSC clearance and encapsulated doxorubicin clearance (R 2 = 0.61, p = 0.02), particularly in patients receiving PLD alone (R 2 = 0.81, p = 0.04). There was a positive relationship (ρ = 0.81, p = 0.01) between maximum grade palmar-plantar erythrodysesthesia toxicity developed and estimated encapsulated doxorubicin concentration in hands. TSC is a phenotypic probe for PLD pharmacokinetics and pharmacodynamics and may be used to individualize PLD therapy in ovarian cancer and for other nanoparticles in development.

Heterogeneity of inhaled particle deposition in airways disease may be a sensitive indicator of physiologic changes in the lungs. Using planar gamma scintigraphy, we developed new methods to locate and quantify regions of high (hot) and low (cold) particle deposition in the lungs.Initial deposition and 24 hour retention images were obtained from healthy (n=31) adult subjects and patients with mild cystic fibrosis lung disease (CF) (n=14) following inhalation of radiolabeled particles (Tc99m-sulfur colloid, 5.4 μm MMAD) under controlled breathing conditions. The initial deposition image of the right lung was normalized to (i.e., same median pixel value), and then divided by, a transmission (Tc99m) image in the same individual to obtain a pixel-by-pixel ratio image. Hot spots were defined where pixel values in the deposition image were greater than 2X those of the transmission, and cold spots as pixels where the deposition image was less than 0.5X of the transmission. The number ratio (NR) of the hot and cold pixels to total lung pixels, and the sum ratio (SR) of total counts in hot pixels to total lung counts were compared between healthy and CF subjects. Other traditional measures of regional particle deposition, nC/P and skew of the pixel count histogram distribution, were also compared.The NR of cold spots was greater in mild CF, 0.221±0.047(CF) vs. 0.186±0.038 (healthy) (p0.005) and was significantly correlated with FEV1 %pred in the patients (R=-0.70). nC/P (central to peripheral count ratio), skew of the count histogram, and hot NR or SR were not different between the healthy and mild CF patients.These methods may provide more sensitive measures of airway function and localization of deposition that might be useful for assessing treatment efficacy in these patients.

This study aims to assess and compare the value of FDG PET with combined In-labeled leukocyte/Tc-sulfur colloid bone marrow (WBC/BM) imaging for diagnosing infection in hip and knee prostheses.In this prospective study, patients with painful hip or knee arthroplasty, who were scheduled to undergo clinical and diagnostic evaluation for prosthesis revision, were included. They have been studied by using FDG PET and WBC/BM scan. This study was institutional review board approved and Health Insurance Portability and Accountability Act compliant. All patients provided written informed consent.A total of 134 hip and 87 knee prostheses, suspected of being either infected or noninfectious loosening, were evaluated. All 221 prostheses underwent FDG PET, whereas both WBC/BM imaging and FDG PET were performed in 88 prostheses. The initial analysis of data from the WBC/BM images demonstrated somewhat suboptimal results compared with those of FDG PET scans on 88 patients. In addition, some patients were not willing to undergo both procedures and therefore participate in this study. Therefore, a decision was made to eliminate WBC/BM imaging from the procedures for the remainder of this research study. This decision was reached partly because of the significant radiation dose delivered from labeled WBC and safety issues related to preparing these labeled cells. Final diagnosis was based on microbiological examinations of the surgical specimens in 125 prostheses and joint aspirations combined with the clinical follow-up of 6 months or more in 86 prostheses. The sensitivity, specificity, positive predictive value, and negative predictive value of FDG PET in hip prostheses were 81.8%, 93.1%, 79.4%, and 94.0%, respectively, and in knee prostheses were 94.7%, 88.2%, 69.2%, and 98.4%, respectively. The sensitivity, specificity, positive predictive value, and negative predictive value of WBC/BM imaging in hip prostheses were 38.5%, 95.7%, 71.4%, and 84.6%, respectively, and in knee prostheses were 33.3%, 88.5%, 25.0%, and 92.0%, respectively. In those cases that underwent both FDG PET and WBC/BM imaging, there was a trend (P = 0.0625) toward a higher sensitivity for FDG PET in hip prostheses, whereas other comparisons did not show any significant differences between the 2 imaging modalities.Based on this study, the diagnostic performance of FDG PET scan in detecting infection in painful hip and knee prostheses is optimal for routine clinical application. Considering the complexity and costs of WBC/BM imaging and related safety issues associated with this preparation, FDG PET seems to be an appropriate alternative for assessing these patients.

The purpose of this study was to determine whether certain factors in the preparation and use of 99mTc-sulfur colloid affected the number of sentinel lymph nodes (SLNs) detected during SLN mapping and during intraoperative SLN identification. The factors that were investigated included the use of a dry heat block versus a hot water bath to heat the 99mTc-sulfur colloid bulk vial, amount of 99m TcOH4 2 added to form the sulfur colloid particles, time between the unit dose calibration and the injection of the dose, and breast quadrant in which the injection occurred. Methods: Data were collected retrospectively and quantitatively analyzed from images and reports of 488 patients with breast cancer who had undergone SLN mapping and intraoperative SLN identification from January 1, 2008, to June 30, 2011, inclusive. The dependent variables assessed were the number of SLNs visualized during lymphoscintigraphy, number of radioactive SLNs removed during surgery, and total number of lymph nodes removed intraoperatively. Results: There was no significant difference in outcomes when comparing the amount of 99m TcOH4 2 added during the preparation process to form the sulfur colloid particles, time between the unit dose calibration time and the time that the unit doses were injected, or location in the breast tissue in which the unit dose was administered. Initially, there were observed significant differences in outcomes when the heating methods used to prepare the 99m Tc-sulfur colloid were compared. When the increased number of patients who were administered a calibrated unit dose activity of 74 MBq in the group using a dry heat block preparation method was taken into account, however, the findings were not significant. Conclusion: The use of a dry heat block versus a hot water bath to heat the 99mTc-sulfur colloid bulk vial, amount of 99m TcOH4 2 added to form sulfur colloid particles, time between the unit dose calibration and the injection of the dose, and breast quadrant in which the injection occurred do not affect the number of SLNs detected during SLN mapping and during intraoperative SLN identification.

Heterotopic liver tissue is a relatively rare finding, which has historically been discovered incidentally during surgery or at autopsy. However, we present a 28-year-old woman who presented to the emergency department with shortness of breath and stabbing chest pain. An emergent CT angiogram of the chest was performed, which incidentally revealed a mediastinal paraesophageal mass. Subsequent endoscopic ultrasound showed a hypoechoic area that appeared to connect to the liver. A liver/spleen scan with SPECT/CT with Tc sulfur colloid demonstrated that the mass was paraesophageal heterotopic liver tissue with a connection to the orthotropic liver by a small stalk.

Objectives: We sought to analyze the characteristics of radioactive lymph nodes with metastatic disease and to explore methods for the localization of sentinel lymph nodes (SLNs) with radionuclide in clinically N0 laryngeal and hypopharyngeal cancer. Methods: Forty-five patients with T1–T4 and clinically N0 laryngeal and hypopharyngeal cancer were recruited. For each patient, a peritumoral submucosal injection of 99mTc-labeled sulfur colloid was administered, and lymph node mapping was performed by lymphoscintigraphy 2 hours after injection. The SLNs were localized during operation by a handheld gamma probe 10 to 12 hours after the injection, and we defined the radioactive counts from the parotideomasseteric region as background values. All lymph nodes that had accumulated radioactivity were harvested and initially termed as SLNs. Selective neck dissection was performed in all patients. The SLN specimens were sent for formal paraffin–embedded sectioning, serial sectioning, and immunohistochemical assay. The results were compared to those for the remaining lymphadenectomy specimen. Resection of the primary tumor depended on its location and the T classification. Results: Sentinel lymph nodes were identified in 41 of 45 patients (51 necks). Sentinel lymph nodes with occult metastases were found in 13 patients (15 necks). In a false-negative case, metastasis was found in a nonsentinel lymph node in 1 of the neck specimens. The SLN identification rate was 92.7%, the sensitivity was 93.7%, the false-negative rate was 6.3%, and the accuracy was 98.0%. In 11 of the 15 necks (73.3%) with pathologically positive SLNs, metastasis was found in the node with the highest radioactivity. Harvesting the first 3 nodes with the highest radioactive counts may identify patients with occult metastatic disease. Conclusions: Excision of the first 3 SLNs with the highest radioactive counts can be used to accurately identify the status of cervical lymph node metastases in patients with clinically N0 laryngeal or hypopharyngeal cancer.

Objectives The purpose of this study was to compare lymphosonography (ie, contrast-enhanced ultrasound imaging [US] after interstitial injection of a US contrast agent) for the detection of sentinel lymph nodes (SLNs) in swine with naturally occurring melanoma tumors to lymphoscintigraphy using blue dye-guided surgical dissection as the reference standard. Also, we sought to determine if lymphosonography can be used to characterize SLNs. Methods Sixty-three swine with 104 melanomas were evaluated. Contrast-specific US was performed after peritumoral injection (1 mL dose) of Sonazoid (GE Healthcare, Oslo, Norway). Lymphoscintigraphy was performed after peritumoral injections of technetium Tc 99m sulfur colloid. Peritumoral injection of 1% Lymphazurin (Ben Venue Labs, Inc, Bedford, OH) was used to guide SLN resection. The accuracy of SLN detection with the two imaging modalities was compared using the McNemar test. The SLNs were qualitatively and quantitatively characterized as benign or malignant based on the lymphosonography results with histopathology and RNA analyses used as the reference standards. Results Blue dye-guided surgery identified 351 SLNs. Lymphosonography detected 293 SLNs and 11 false-positives, while lymphoscintigraphy detected 231 SLNs and 20 false-positives. The accuracy of SLN detection was 81.8% for lymphosonography, which was significantly higher than the 63.2% achieved with lymphoscintigraphy (P < .0001). The accuracy of lymphosonography for SLN characterization was 80%. When the size of the enhanced SLN was taken into consideration to characterize SLNs, the accuracy was 86%. Conclusions Lymphosonography is statistically better than lymphoscintigraphy for the detection of SLNs in this animal model. The ability to use lymphosonography as a means to characterize SLNs as benign or malignant is limited.

Myelolipoma is a rare hormonally inactive, benign tumor composed of mature adipose tissue and hematopoietic cells. It frequently involves the adrenal gland but could be located away from this organ in the thorax, retroperitoneum, or presacral region. The extraadrenal lesion may simulate oth

PURPOSE This study was performed to determine whether endoleaks could be detected after endovascular aneurysm repair (EVAR) with use of technetium-99m sulfur colloid and 99m Tc-labeled red blood cell (RBC) nuclear medicine scans. MATERIALS AND METHODS There were 13 patients enrolled in this study: nine with endoleaks seen on computed tomographic (CT) angiography and four with no endoleak on CT angiography. All patients underwent regularly scheduled surveillance CT angiography examination after EVAR to evaluate for endoleak. Endoleak detection was then attempted in each patient with two nuclear medicine scans: a 99m Tc sulfur colloid scan and a 99m Tc-labeled RBC scan. Flow images (5 seconds per frame) were obtained for 1 minute after intravenous administration of 555 MBq (15 mCi) 99m Tc sulfur colloid. Sequential dynamic images were then obtained every minute for 30 minutes. Next, a 99m Tc-labeled RBC study was performed after the intravenous administration of 370–1,073 MBq (10–29 mCi) in vitro labeled 99m Tc RBCs. Flow images were obtained, followed by sequential dynamic images obtained every minute for 30 minutes. Single photon emission CT images of the abdomen were then acquired. The nuclear medicine scans were evaluated for the presence or absence of endoleak independent of the CT angiography findings. RESULTS Of the nine patients with endoleaks on CT angiography, seven (78%) had them detected by nuclear medicine examinations. Two of the nine endoleaks seen on CT angiography (22%) were not seen on either scintigraphic examination. All patients with no endoleak on CT angiography had their nuclear medicine scans correctly interpreted as showing no endoleak present ( n = 4; 100%). No complications occurred as a result of the nuclear medicine scans. CONCLUSIONS Endoleaks can be detected with 99m Tc sulfur colloid and 99m Tc-labeled RBC nuclear medicine scans. This initial work suggests that the sensitivities of these scintigraphic scanning methods for endoleak detection are lower than that of CT angiography.

Objectives To establish whether 9 9 m TC stannous (Tc-Sn) colloid is a suitable alternative to 9 9 m Tc sulfur (Tc-S) colloid for gastrointestinal studies, we compared the per cent binding to egg solids (%BS) and radiochemical purity (RCP) of both colloids in digesting media. Methods Egg white and yolk containing colloids were cooked separately and mashed. Samples of 4-5 g were digested over 2-3 h (37°C) in excess simulated gastric juice (SGJ: 15 ml of 0.1 M HCI and 0.5 g . l - 1 pepsin) or water, centrifuged, imaged with a gamma camera and the %BS computed. RCP was determined in aspirates taken from these preparations and from solutions of colloid added directly to SGJ. Results The %BS in egg white after 3 h in SGJ for both colloids were similar: Tc-Sn, 62 ′ 8 (n=12); Tc-S, 61 ′ 6 (n=8), but markedly lower than 95% (the often quoted literature value). Egg yolk was digested more rapidly than egg white: %BS after 2 h in SGJ for Tc-Sn colloid was 55 ′ 10 (n=5) in the yolk, compared to 77 ′ 4 (n=5) in the white (P 94% over 3 h but for Tc-Sn colloid was as low as 14%. For egg white, the RCP in SGJ was 91-96% for Tc-S and 80-91% for Tc-Sn. For egg yolk the RCPs in SGJ were similar for both colloids (>90%). The RCP in water digesting egg white or yolk containing either colloid was always lower than in the corresponding SGJ aspirates, indicating a leakage of small amounts of non-colloidal 9 9 m Tc. Conclusions Although 9 9 m Tc-Sn almost completely dissociates in SGJ, once cooked in egg it is digested similarly to 9 9 m Tc-S. Variations in the size of digesting egg fragments and in SGJ composition can reconcile the lower %BS values obtained with previously reported higher results. 9 9 m Tc-Sn colloid cooked in egg appears suitable for gastrointestinal studies.

The quantitative liver-spleen scan (QLSS) can estimate the functional hepatic mass and the organ volumes by precise measurement of sulfur colloid (SC) distribution. The normal range determined in prior studies was estimated from patients with absence of chronic liver disease in which intense fasting appeared to produce slightly abnormal values. This study was to determine the effect of fasting or fed status and colloid particle size on quantitative measurements from the QLSS in a small cohort of normal individuals. Twelve persons without any medical problems had QLSS taken twice, 2 weeks apart, one fasting and one postprandial. Patients were scanned after injection of 5-6 mCi of SC; six patients were given solution A (5- to 12-microm particle size) and six patients solution B (2- to 12-microm particle size). SPECT and planar analysis were performed. SC distribution of total counts between the liver and the spleen {[L/(L + S)]t ratio}, liver-spleen index (LSI), and liver-bone marrow index (LBI) were calculated. The perfused hepatic mass (PHM) is the average of the LSI and LBI. Spleen and liver volumes are expressed as milliliters per pound ideal body weight (IBW). Results showed that the liver and spleen volumes (solution B postprandial, 9.27 +/- 2.48 and 1.47 +/- 0.57 ml/lb IBW, respectively) and LBI were not affected by the type of SC solution or by ingestion status. L/(L + S) total and pixel count ratios were significantly higher for solution B and postprandial studies. [L/(L + S)]t, LSI, and PHM increased significantly (P < 0.05) from fasting to postprandial for solution A (0.71 +/- 0.13 vs 0.79 +/- 0.08, 80 +/- 14 vs 91 +/- 8, and 102 +/- 10 vs 106 +/- 8, respectively) and for solution B (0.81 +/- 0.05 vs 0.90 +/- 0.02, 86 +/- 4 vs 95 +/- 3, and 101 +/- 5 vs 110 +/- 3). Neither fasting nor postprandial LSI and PHM were significantly different between solution A and solution B. We conclude the following. (1) The QLSS functional indices in "true" normal patients fall within the previously reported normal range. (2) Calculated liver and spleen volumes are not altered by fasting or sulfur colloid particle size. (3) Fasting significantly decreased the [L/(L + S)]t, LSI, and PHM. (4) A postprandial scan may be preferable since the normal values for [L/(L + S)]t, LSI, and PHM are greater, with a narrower range, than fasting values.

Background The purpose of this study of sentinel lymph node biopsies (SLN) was threefold: to compare the reliability of lymphazurin blue dye to radioactive technetium 99m sulfur colloid (TC); to evaluate the reliability of frozen section examinations of sentinel lymph nodes; and to determine how much SLN dissections prolonged operative time. Study design We evaluated the records of 263 consecutive patients with intermediate and high-risk melanomas (1.0 mm or thicker, or Clark Level IV or greater), who were treated by a single surgeon at the Yale Melanoma Unit between October 1, 1997, and September 30, 2001, and followed for more than 18 months. Results A total of 655 SLN were identified and removed from these 263 consecutive patients. Radioactive colloid was found to be more reliable (100%) in identifying the SLN than lymphazurin blue dye (51%) in the nodes of the patients. Twenty-eight patients (11%) had positive sentinel lymph nodes, and 2 patients (7%) had false-negative frozen sections. Three patients (11%) had false-negative frozen sections; tumor was found subsequently on permanent sections only after special immunohistochemical stains were used. The location or removal of SLN did not prolong the operative procedure unreasonably, requiring an average of 7 to 20 minutes for removal of SLN, and 33 minutes for frozen section reports, during which time the primary tumor resection and wound coverage were performed. Conclusions SLN were found in all 263 patients. All SLN were identified reliably with radioactive colloid. Because blue dye was found in only half of the radioactive nodes, it is not appropriate to use this as the only marker for locating the SLN. This large series of patients attests to the reliability of frozen sections in identifying SLN harboring metastases, with 82% of the patients with nodal metastases identified in this fashion.

Aim To assess the extent to which bone marrow scintigraphy (BMS) makes the interpretation of leucocyte scintigraphy (LS) easier and improves its diagnostic value. Methods Seventy-three 111In LSs, 99mTc hydroxymethylene diphosphonate bone scintigraphies (BSs) and 99mTc sulfur colloid BMSs were performed in 60 patients with suspected infection related to a hip prosthesis or knee prosthesis, either in situ (+group, n = 43) or after removal for septic loosening (-group, n = 30). Bacteriological samples were obtained from all patients. LS was interpreted together with BS (LS-BS) or with BMS (LS-BMS) by three independent readers. Results The concordance among readers, estimated by the kappa test, was average with LS-BS (kappa/kappam coefficients = 0.58, 0.58 and 0.46, respectively, for the three pairs of readers) and excellent with LS-BMS (kappa/kappam coefficients = 1.00 for the three pairs of readers). With LS-BS, 64/219 interpretations were equivocal whereas only one was equivocal with LS-BMS. Sensitivity, specificity and accuracy of LS-BMS were, respectively, 80%, 94% and 91% in the +group, and 33%, 100% and 93% in the -group. Conclusion We conclude that (1) the interpretation of the results for LS-BMS is very easy, in contrast to LS-BS; (2) the diagnostic value of LS-BMS for detecting infected joint prostheses is good; and (3) additional data are needed to assess the accuracy of LS-BMS when the prosthesis has been removed.

Lymphoseek is a new radiopharmaceutical that accumulates in lymphatic tissue by binding to a receptor that resides on the surface of macrophage cells. We conducted a phase I clinical trial in which Lymphoseek was compared with filtered [(99m)Tc]sulfur colloid (fTcSC) for sentinel node detection in patients with breast cancer.Twelve women (42-71 years) with breast cancer were randomly assigned to a 3-hour imaging protocol with peritumoral/subdermal injections (.5 mCi) of either Lymphoseek (1 nmol; molecular weight, 28 kDa; diameter,.007 micro m) or.2 micro m of fTcSC. Serial images were acquired for 180 minutes. Sentinel nodes, excised within 4.2 to 7.3 hours of administration, were assayed in a dose calibrator.The receptor-binding agent, Lymphoseek, exhibited a significantly (P =.0025) faster injection site clearance (rate,.255 +/-.147/hour; fTcSC rate,.014 +/-.018/hour); the mean Lymphoseek clearance half-time was 2.72 +/- 1.57 hours compared with 49.5 +/- 38.5 hours for fTcSC. The primary sentinel node uptake of Lymphoseek (range,.02%-1.12%; mean,.55% +/-.43%) and fTcSC (range,.00%-1.93%; mean,.65% +/-.63%) did not differ (P =.75). Lymphoseek exhibited a lower mean number of sentinel nodes per study (n = 1.3) than fTcSC (n = 1.7) and a higher concordance with Lymphazurin.The molecular receptor-binding agent Lymphoseek demonstrated faster injection site clearance and equivalent primary sentinel node uptake when compared with fTcSC.

Interferon (IFN) provides effective treatment in some patients with chronic hepatitis. The clarification of factors predictive of therapy response would be helpful in identifying patients who would benefit from treatment. In this study, we evaluated the potential utility of Tc-99m sulfur colloid liver/spleen and Tc-99m-disofenin hepatobiliary scintigraphy to predict therapy response to IFN in patientswith chronic active hepatitis. The study group consisted of ten patients with chronic viral hepatitis B who were treated with 4.5 units of interferon alpha for 12 months. Prior to the start of the therapy, sulfur colloid scintigraphy was obtained by which the liver/spleen ratios were derived. Hepatobiliary scintigraphy was performed on a separate day and time-activity curves were generated from regions of interest drawn over the liver, heart and gall-bladder. The index of blood and liver clearance time was calculated. Histological grading and laboratory values were obtained for clinical correlation. Responders (n = 6) to IFN were defined as those who improved clinically with normalized transaminase levels and had HBeAg seroconversion. On SC scintigraphy, the liver/spleen ratio of non-responders was significantly lower than responders (median values: 0.69 vs. 1.16, p = 0.01) but on hepatobiliary scintigraphy no statistically significant parameters were found to predict response to interferon therapy.

OBJETIVO: Verificar a possibilidade de realizar esplenectomia subtotal na presença de lesões graves do baço por trauma ou que acometam o seu pedículo vascular principal, avaliar as repercussões clínicas, hematológicas e imunológicas que essa operação pode trazer nos pós-operatórios, viabilidade e a função de filtração do pólo superior do baço remanescente. MÉTODOS: Foram estudados 34 pacientes, 25 submetidos à esplenectomia subtotal (Grupo I), nove à esplenectomia total sem preservação de tecido esplênico (Grupo II), 22 pessoas com baços íntegros (Grupo III). No pós-operatório tardio realizaram-se exames hematológicos (hematimetria, hemoglobina, hematócrito, plaquetas, leucócitos globais e segmentados, linfócitos e corpúsculos de Howell Jolly). Dosaram-se as imunoglobulinas (IgA, IgM e IgG) e linfócitos T totais (LTT), linfócitos T ativos (LTA) e linfócitos B. Realizou-se cintilografia esplênica com enxofre coloidal marcado com 99mTc. RESULTADOS: Em nenhum dos grupos houve leucocitose ou trombocitose. Os corpúsculos de Howell-Jolly foram observados no Grupo II e neste grupo a IgM esteve reduzida. A cintilografia demonstrou tecido esplênico captante no Grupo I. CONCLUSÃO: A esplenectomia subtotal pode ser uma alternativa cirúrgica para as lesões graves distais do baço ou quando o seu pedículo principal estiver acometido e não leva a repercussões clínicas e laboratoriais nos pacientes submetidos a esse procedimento. PURPOSE: To evaluate clinical and laboratory variables in patients submitted to subtotal splenectomy. METHODS: 34 patients with severe trauma of the spleen and its pedicle were studied: 25 patients were submitted to subtotal splenectomy, preserving only the upper pole of the spleen (Group I), 9 were submitted to total splenectomy (Group II), and other 22 people with intact spleen were the control (Group III). Immediate and late postoperative complications were investigated. Laboratory exams were performed in the late postoperative period (red blood cells, hemoglobin, white blood cells, platelets and Howell-Jolly bodies). We studied the B- and T-lymphocyte counts and the immunoglobulins A, G and M (IgA, IgG and IgM) levels. Splenic scintigraphy with technetium 99mTc sulfur colloid was carried out on all patients. RESULTS: Group II presented Howell-Jolly bodies increased and low level of immunoglobulin M. The splenic scintigraphy demonstrated the viability and the filtering function of the splenic remnant in Group I . CONCLUSIONS: Subtotal splenectomy is a surgical alternative technique for treatment of severe distal injuries of the spleen or when its main vessels are damaged.

REPLY: We thank Dr. Garin et al. for their expert insights into the complex topic of radioembolization dosimetry. For 90Y hepatic radioembolization, 99mTc-macroaggregated albumin (99mTc-MAA) administered as an intraarterial simulation imaging agent is primarily used for calculation of the lung shunt

BACKGROUND: Injection of Technetium 99m sulfur colloid (Tc-99m-SC) into the subareolar lymphatic plexus provides a rapid and reliable method of identifying breast sentinel lymph nodes and their lymphatic connections to the areola, termed sentinel lymphatic channels (SLCs). The objective of this study was to define the anatomic origin, number, and direction of the SLC in relation to the areola after subareolar injection of Tc-99m-SC. STUDY DESIGN: Using a hand-held goniometer, the exit angle (θ e ) and direction from the vertical (to the patient's right or left) of SLCs were determined in 87 successful preoperative lymphoscintigrams (46 left breast and 41 right breast). RESULTS: One major lymphatic trunk was identified in 91% of cases (n = 79), and two lymphatic trunks were identified in 9% of cases (n = 8). Overall, 24% (n = 21) of major lymphatic trunks exited the areola vertically (θ e = 0 degrees), 33% (n = 29) exited the areola with θ e = right or left 1 to 30 degrees, and 32% (n = 28) exited with a θ e = right or left 31 to 60 degrees. In total, 90% (n = 78) of SLCs exited the areola with a θ e = right or left 0 to 60 degrees, equivalent to 10 to 12 o'clock in the right breast, and 12 to 2 o'clock in the left breast. CONCLUSIONS: Radial angular measurements of SLCs from preoperative lymphoscintigrams performed by SA injection confirm that the origin of the majority of SLCs is within the upper, outer edge of the areola, and that all SLCs ultimately traverse the upper, outer quadrant of the breast and terminate on axillary sentinel nodes.

The reliability of combined indium-111 leukocyte/technetium-99m sulfur colloid scans, with and without the addition of blood pooling and blood flow studies, in the diagnosis of infected total joint arthroplasty was investigated. Both scans were performed on 58 patients before reoperation of total hip or knee arthroplasty in the period 1996-1999. Results for imaging alone included 100% specificity, 46% sensitivity, 100% positive predictive value, 84% negative predictive value, and 88% accuracy. Inclusion of blood pooling and flow phase data improved results to 66% sensitivity, 89% negative predictive value, and 90% accuracy, with reductions in specificity (98%) and positive predictive value (91%). Routine use of these radionuclide scans is not supported by these data.

Objectives/hypothesis Because sentinel lymph nodes are the first lymph nodes that drain a primary cancer site, results of sentinel lymph node (SLN) biopsy indicate status of the regional lymph nodes. Preoperative lymphoscintigraphy and intraoperative combined application of the handheld gamma probe and blue-dye technique (i.e., the "combined technique") was used previously to accurately identify the SLN, mostly in melanoma of the extremities and trunk and, sometimes, in melanoma of the head or neck, which is anatomically complex. Because of this complexity, melanoma in the head or neck is inherently problematic to treat: Localization of the SLN can be difficult or impossible because the primary cancer site can be near or overlapping the nodal basin. The objective of the present study was to determine the technical modifications and other considerations that can make SLN localization feasible in cases of melanoma occurring near or overlapping the nodal basin in the head or neck. Study design/methods In a retrospective study of clinical records containing our database of melanoma diagnoses made between January 1996 and December 1999, we identified 27 patients diagnosed with stage I or II primary melanoma of the head or neck with clinically negative neck nodes who also had had preoperative lymphoscintigraphy. Of the 27 patients (17 male and 10 female patients; mean age, 54 y), 24 had SLN biopsy by intraoperative localization using both the handheld gamma probe and the blue-dye technique. Results Among the 27 patients who had SLN mapping, a median Breslow thickness of 1.8 mm was noted. Sentinel lymph node was noted at preoperative lymphoscintigraphy in 26 (96%) of the 27 patients. Activity of technetium Tc 99m (Tc-99m) sulfur colloid injected ranged from 10 to 1000 microCi (0.37 to 37 megabecquerel [MBq]). Intraoperative use of the combined technique for sentinel lymphadenectomy was successful in 92% of patients. Sentinel lymph nodes were identified in all 14 patients who received Tc-99m sulfur colloid at an activity level less than 60 microCi (2.2 MBq); mean activity level of injected TC-99m sulfur colloid was 28 microCi (1.04 MBq). Sentinel lymph nodes were identified in 8 (80%) of 10 patients who received Tc-99m sulfur colloid at an activity level greater than 100 microCi (3.7 MBq); mean activity of injected Tc-99m sulfur colloid in these patients was 482 microCi (17.8 MBq). A mean number of 1.4 sentinel lymph nodes per patient was identified at preoperative lymphoscintigraphy, and a mean number of 3 sentinel lymph nodes per patient was identified intraoperatively using the combined technique. Tumor recurrence was seen in 2 (10%) of the 19 patients who had cancer-free SLN at mean follow-up of 18 months (range, 1 to 47 mo). Sentinel lymphadenectomy of the parotid region did not injure the facial nerve in any patients. Conclusions For patients with primary melanoma that is near or overlaps the nodal basin in the head or neck, SLN biopsy can be accurately performed using Tc-99m sulfur colloid at low activity levels (10 microCi to 60 microCi [0.37 to 2.2 MBq]. However, background radiation from the primary injection site can incorporate the SLN, making localization at preoperative lymphoscintigraphy difficult if not impossible; therefore, the high doses commonly used for melanoma of the extremities and trunk (500 to 2000 microCi [18.5 to 74 MBq]) should not be used for melanoma of the head or neck if the primary site is near or overlaps the nodal basin. In addition, absorption of Tc-99m sulfur colloid by salivary glands increases background radiation in the nodal basin; therefore, use of the handheld gamma probe for intraoperative localization of SLN can be problematic in regions where lymph nodes are adjacent to or within the substance of the salivary gland (i.e., the submandibular and parotid glands).

A 59-year-old man with essential thrombocytosis was examined for abdominal pain. Splenic infarction was diagnosed on a computed tomographic scan. The Tc-99m heat-denatured RBC scan showed viable splenic tissue that was not evident on the computed tomographic scan or Tc-99m sulfur colloid scintigraphy.

Background: Numerous techniques and materials show accuracy in localizing the sentinel lymph node (SLN). We hypothesized that subareolar injection of material would localize the SLN as effectively as peritumoral injection. Methods: Thirty-eight patients were injected with technetium-99 sulfur colloid either peritumorally or subareolarly in addition to the injection of blue dye around the tumor. Radioactive SLNs were localized using a hand-held gamma probe. Results: Nineteen patients were included in each of the two groups, peritumoral and subareolar. SLNs were found in all patients injected subareolarly and in 18 of 19 injected peritumorally. The false-negative rate was 20% for peritumoral injection and 0% for subareolar injection. Conclusions: The results suggest that subareolar injection was as accurate, if not more accurate, than peritumoral injection for localizing the SLN. This technique is simpler than peritumoral injection and does not require injection under image guidance for nonpalpable lesions.

Objective:We investigated the propagation of viral-size particles by lymph and blood after subcutaneous injection. Methods:In the canine model, transport of [99mTc] sulfur colloid particles of different sizes was studied in different settings in venous blood and lymph for 45 minutes after inoculation. Results:The mean arrival time of particles in the blood was 2.10 ± 0.46 minutes and 8.87 ± 1.72 minutes in the lymph. Lymph flow in the canine leg was 28.79 ± 2.09 µl/min and was increased by leg massage. The particle concentration was 1000 times higher in the lymph fluid than in blood. Particle flux values were comparable in blood and lymph. The accumulation of particles in blood initially rose faster than in lymph. Accumulation in lymph rises slower but continues longer and reaches higher values. Ninety percent of the inoculum remains at the injection site for at least 45 minutes. Particle size matters more in blood distribution. Leg massage enhances particle transport by lymph. Conclusions:After subcutane...

Background: The combination of gamma-probe radiolocalization and blue-dye mapping of sentinel lymph nodes (SLNs) has been advocated as the most accurate method for staging the clinically negative axilla in breast cancer patients, but the technical aspects of these procedures are not fully characterized in the literature. In this study, we compared the success of SLN localization in 134 consecutive breast cancer patients using blue dye plus two different preparations of radiocolloid. Study Design: A retrospective analysis of a prospectively maintained data base was performed to assess SLN localization in two cohorts of patients. Unfiltered technetium-99m (Tc-99m) sulfur colloid (in 77 patients; group I) was compared with filtered Tc-99m sulfur colloid (in 57 patients; group II). All patients had a peritumoral injection of blue dye and isotope, followed immediately by lymphoscintigraphy to confirm radioactivity at the injection site and to image the SLN. Statistical analysis was performed using the Pearson chi-square test. Results: Unfiltered Tc-99m sulfur colloid was superior to the filtered radiocolloid in localizing the SLN (88% versus 73%; p=0.03). SLN imaging by lymphoscintigraphy was also more successful in the unfiltered group. Using the combination of blue dye and radiolocalization, SLNs were identified in 94% of patients. Conclusions: For optimal localization of the SLN in breast cancer patients, surgeons should use the combined technique of blue-dye mapping and gamma-probe localization using unfiltered Tc-99m sulfur colloid.

To evaluate the use of 0.22-micron filtration of technetium-99m sulfur colloid particles in the optimization of lymphoscintigraphy.Forty-one consecutive lymphoscintigraphic studies obtained with 0.22-micron filtration of Tc-99m sulfur colloid in 41 patients (26 men, 15 women; average age, 55.4 years) and 41 consecutive studies obtained with 5.0-micron filtration in 41 patients (20 men, 21 women; average age, 54.5 years) were retrospectively, randomly reviewed. Studies were evaluated for lymphatic channel depiction and sentinel lymph node depiction. Studies included immediate flow images (obtained at 10 seconds per frame) and multiview static images obtained up to 2 hours after intradermal Tc-99m sulfur colloid injection.The number of drainage beds visualized was 52 with 5.0-micron filtration and 51 with 0.22-micron filtration (P = .570). The number of lymphatic channels visualized was 45 with 5.0-micron filtration and 75 with 0.22-micron filtration (P = .006). The number of lymph nodes visualized was 102 with 5.0-micron filtration and 123 with 0.22-micron filtration (P = .123). The number of studies judged as optimal (i.e., depicted lymphatic channels leading to sentinel nodes) was 10 with 5.0-micron filtration and 19 with 0.22-micron filtration (P = .038). The number of studies with depicted lymph nodes but no depicted lymphatic channel was 15 with 5.0-micron filtration and six with 0.22-micron filtration (P = .023).The use of 0.22-micron filtration in the preparation of Tc-99m sulfur colloid substantially improves study quality and increases the diagnostic certainty in the identification of sentinel lymph nodes.

Background: The purpose of this study was to determine whether the sentinel lymph node (SLN) localization technique, which uses blue dye and 99mTc-labeled sulfur colloid, provides advantages over blue dye alone in the management of patients with stages I and II cutaneous melanoma. Methods: The records of 626 consecutive patients with melanoma who underwent lymphatic mapping and SLN biopsy between 1991 and 1997 at the M.D. Anderson Cancer Center were reviewed. Lymphatic mapping was performed with isosulfan blue dye alone (n = 252) or in combination with 99mTc-labeled sulfur colloid accompanied by a hand-held gamma probe (n = 374). SLNs were defined as those that stained blue or demonstrated increased focal radiotracer uptake. Results: SLN identification rates improved from 87% (dye alone) to 99% (dye and colloid) (P < .0001) with the combined technique in all anatomic sites examined. The mean number of SLNs harvested from each basin was significantly greater in the patients mapped with dye and colloid (1.74 vs 1.31; P < .0001). Occult metastatic disease was identified in 17.5% of all patients and did not significantly differ between groups. In 92% of patients who had at least one positive SLN and were mapped with both agents, lymphatic metastases were identified in the SLN that contained the greatest radiotracer uptake. In 19% of cases the first blue SLN harvested did not contain the greatest radiotracer uptake. Conclusions: SLN identification is enhanced by the addition of radiolabeled sulfur colloid and intraoperative use of the hand-held gamma probe and may identify SLNs missed by the blue dye alone. These data support the combined use of radiolabeled sulfur colloid and blue dye in lymphatic mapping procedures to improve the nodal staging of stages I and II melanoma. (Surgery 1998;124:203-210.)

Purpose Tl-201 chloride has been used to image viable tumors in various sites of the body. There has been limited use of Tl-201 below the diaphragm because of normal uptake in the liver, spleen, kidneys, and intestines. The use of sequential Tl-201 and Tc-99m sulfur colloid in the detection and characterization of suspected hepatocellular carcinoma (HCC) was prospectively evaluated. Methods Four patients with indeterminate liver nodules on radiologic imaging studies were studied with sequential Tl-201 and sulfur colloid liver scans on a triple-headed gamma camera with planar and SPECT acquisition. All patients had subsequent pathologic correlation. Results There were three focal nodular HCC lesions and one case of multicentric HCC, size varying between 1.9 cm and greater than 4.0 cm (multicentric HCC). In all lesions, Tl-201 SPECT images showed abnormal increased uptake at sites of HCC, which corresponded to areas of photopenia on sulfur colloid. Computed tomography detected a lesion in two of four patients, whereas US was positive in all patients. However, US was specific for tumor in only one patient and CT was not specific in any patient. Conclusion We believe that in patients with suspected HCC, Tl-201 SPECT imaging will have an important role in the detection and characterization of HCC, especially in the cirrhotic patient. Planar Tl-201 hepatic images will usually be normal, except in large lesions, and high-resolution SPECT technique is essential in successful liver tumor imaging.

A cylindrical shape prototype aerosol inhalation device that was previously shown to enhance pulmonary deposition from a nebulizer was evaluated for its performance in conjunction with a pressurized metered dose inhalation aerosol (MDI). Gammascintigraphic studies in human volunteers using radiolabeled technetium Tc 99m sulfur colloid (TSC) MDI showed this prototype to enhance sulfur colloid deposition in the lungs and minimize oropharyngeal deposition. A second in vivo study conducted with a new compact prototype designed for commercial development showed similar pulmonary deposition profiles with the radiolabeled TSC MDI. Data from these studies with the radiolabeled MDI show that both the prototypes enhanced pulmonary deposition and minimized oropharyngeal deposition in comparison with commercial inhalation devices.

In a retrospective study, technetium 99m sulfur colloid scintigraphy was used to evaluate reticuloendothelial system function in 61 dogs with single congenital and 40 dogs with multiple acquired portasystemic shunts. Whole body reticuloendothelial function was measured by calculating the plasma clearance rate constant from a dynamic study of liver uptake of 99mTc sulfur colloid. Relative liver, spleen, and lung uptake, and a ratio of hepatic:extrahepatic uptake were measured on static equilibrium images. Results were compared with those of a group of 26 normal dogs. Compared with values for the group of normal dogs, the plasma clearance rate constant, relative liver uptake, and hepatic:extrahepatic uptake ratio were significantly decreased, and relative spleen and lung uptake were significantly increased in dogs with portasystemic shunts (P < .0001). The only significant difference between dogs with single congenital versus multiple acquired shunts was that the relative splenic uptake was higher in the former group (P < .0002). Based on these results, we concluded that dogs with portasystemic shunts have significantly impaired reticuloendothelial function. The primary cause of this dysfunction is likely a reduction in effective liver blood flow. Increases in spleen and lung reticuloendothelial activity did occur, but only partially compensated for the reduction of liver reticuloendothelial activity. Possible mechanisms for the increased spleen and lung uptake are discussed.

Gallium-67 is routinely used for follow-up of patients with malignant melanoma. However, its nonspecificity for melanoma and its high rate of false-positive results have always been a matter of concern. The authors describe a patient who encountered serious problems with the use of gallium. Because gallium is taken up well by the liver and by melanoma, results of gallium scintigraphy of the liver may appear normal even if there is metastatic disease. In this patient, results of gallium scintigraphy of the liver were negative for metastasis but revealed extrahepatic foci detected by the monoclonal antibody. Computed tomography showed areas of attenuation, revealing only a few intrahepatic tumors and no extrahepatic disease. Tc-99m SC revealed intrahepatic metastases, but no extra-hepatic metastases were seen. A monoclonal antibody (ZME-018) scintigram did reveal hepatic metastases along with probable small, extrahepatic, metastatic foci. Overall hepatic uptake of the monoclonal antibody was relatively low. An image subtraction algorithm was devised whereby the sulfur colloid image was subtracted from the gallium scintigram. The resultant image revealed both the intrahepatic and extrahepatic metastases seen on the ZME-018 images. It is likely that in the past many hepatic metastases have been missed because Tc-99m SC images have not been routinely used as part of melanoma management protocols. The uptake of the ZME-018 by the tumor was significantly higher than that of the normal liver, suggesting that ZME-018 labeled with the appropriate emitter may be an effective specific therapeutic tool in selected patients.

The increased incidence of infection in cirrhotics may in part be attributable to dysfunction of the reticuloendothelial system (RES) in removing pathogens from the circulation. The portosystemic shunting (PSS) that results from portal hypertension in cirrhotics may compromise RES function by allowing enteric pathogens to be shunted away from the Kupffer cells. A well-characterized model of portal hypertension induced by partial portal vein ligation (PVL), in which there is no hepatic parenchymal cell damage, was used. Kupffer cell function is unaltered and the effect of PSS alone on overall RES function can be evaluated. In addition to the usual immunologically inert [99mTc]sulfur colloid, an actual pathogen was also evaluated. PVL and sham-ligated rats were given either [99mTc]sulfur colloid or E. coli via the ileocolic vein. The right femurs, lungs, livers and spleens of the animals receiving 99mTc were excised and the radioactivity counted. The lungs, livers, and spleens of the animals receiving E. coli were liquefied and the bacteria were quantified. For both groups the ratios of 99mTc or E. coli in the lung, spleen, and femur to liver were calculated. PVL rats had significantly more 99mTc in the lung, spleen, and femur than the sham rats. There were also significantly more E. coli in the lungs for PVL rats but no significant difference in the spleen counts. These results imply that even in the absence of Kupffer cell dysfunction, PSS alters reticuloendothelial system function by causing a greater distribution of pathogens to the periphery. This altered distribution may contribute to an increased susceptibility to infection in cirrhotics.

We report the finding of bleeding into right lung from a ruptured amoebic liver abscess. A 25-year-old male presented with pain in the right lower chest and cough associated with expectoration of chocolate-colored sputum. Radiographs of chest showed right-sided pleural effusion. Serial images of Tc99m-sulfur colloid study revealed progressive accumulation of radiotracer in the upper photopenic area extending into the right lung region suggestive of active bleeding from the abscess cavity.

A case of veno-occlusive disease of the liver of unknown etiology is reported. In the case, the gross abnormality of liver parenchyma, ascites, and colloid shift to spleen, bones, and lungs found on a Tc-99m SC liver-spleen scan, and confirmed on liver biopsy, resolved completely on follow-up. Histologic correlation and a brief review of the literature are presented.

Sclerosing angiomatoid nodular transformation (SANT) is a benign, proliferative vascular lesion affecting the spleen. Few reports detailing the cross sectional and PET appearance of this lesion are available, and the lesion's behavior with ⁹⁹(m)Tc-sulfur colloid scintigraphy is previously unreported. Sclerosing nodular transformation of the spleen shows increased tracer accumulation on positron emission tomography, and a central scar-like appearance with an enhancing capsule and radiating septae on CT and MR studies that reflects the gross and histopathological features of the lesion may be visible. An understanding of this pathological finding may allow prospective recognition of the sclerosing nodular transformation of the spleen on cross sectional imaging studies.

Background With regard to the sentinel lymph node (SLN) procedure in breast cancer, the study analyzed the impact of discrepancies between the number of clinically and histologically identified SLN, the impact of removing additional non-hot/non-blue but clinically conspicuous lymph nodes (LN), and whether the application of blue dye for mapping is necessary. Methods We analyzed 391 SLN procedures in which 928 SLN were removed. In all cases, radiolabeled colloid and blue dye were used for SLN mapping. Results In 60 cases (15.3%), additional LN that were not identified by the surgeon were found by histological examination. In 22 cases (5.3%), tissue which clinically resembled an SLN but was histologically connective tissue, was removed. In 76 cases (19.4%), 133 non-hot/non-blue but clinically conspicuous LN were removed. These additionally removed LN, however, did not alter the axillary staging. In 50.8% of the cases ( n = 471), the SLN were marked only by radiolabeled colloid. In 27 cases (2.9%), the surgeon identified the LN through blue coloration alone; however, in all of the latter cases, these SLN were not deciding for axillary staging. Conclusion The mapping agents may accumulate in axillary tissue and mimic the existence of an SLN. The radiolabeled colloid method alone gives excellent mapping results. The additional application of blue dye is avoidable. Exact surgical preparation enables removal of the SLN only and avoids removal of LN-containing adjacent tissue. The removal of further clinically identifiable enlarged non-hot LN should only be done if there is strong suspicion of metastatic involvement.

The use of 99mTc-sulfur colloid lymphoscintigraphy for the determination of lymph flow patterns from a tumor site and localization of the sentinel node has been widely adopted. However, the effects of multiple injections of the radiopharmaceutical can range from mild discomfort to pain. pH-adjusted lidocaine HCl coadministered with 99mTc-sulfur colloid presents a risk of introducing instability of the radiopharmaceutical, which could lead to aggregation, possibly impeding the kinetics of lymphatic drainage from the tumor site. Methods: In the present study, lidocaine pH-adjusted with 4.2%, 6.3%, or 8.4% sodium bicarbonate was added to the 99mTc-sulfur colloid radiopharmaceutical to monitor effects on radiochemical purity, zeta-potential, particle size, and pH. These parameters were then used to evaluate the short-term stability of the preparation. Results: The study revealed that the formulation of lidocaine pH-adjusted with 8.4% sodium bicarbonate added to 99mTc-sulfur colloid demonstrated a similar change in zeta-potential (−4.09 ± 2.90 mV) and particle size (10–330 nm) to that of control filtered 99mTc-sulfur colloid (−5.09 ± 1.68 mV and 11–343 nm, respectively). However, the 4.2% preparation showed a zeta-potential of −3.01 ± 2.24 mV and a particle size range of 10–351 nm. The pH of the 8.4% buffered preparation, at 7.1, was closer to physiologic pH than was the control, at 6.0. The 6.3% pH-adjusted lidocaine–99mTc-sulfur colloid preparation failed radiochemical purity; thus, it was not included in the analysis. Conclusion: Compared with other 99mTc-sulfur colloid test formulations of 4.2% and 6.3% pH-adjusted lidocaine, the 8.4% sodium bicarbonate pH-adjusted lidocaine–99mTc-sulfur colloid preparation, taken as a whole, yielded superior quality-control parameters. This formulation would be an acceptable alternative to the control.

Seventy-three patients with various underlying disorders that could potentially alter distribution of bone marrow underwent In-111 labeled autologous leukocyte and Tc-99m SC marrow imaging to exclude musculoskeletal infection. There were 22 cases of infection among the 73 patients studied. When interpreted in isolation, labeled leukocyte images were considered positive for infection when uptake of labeled cells in the region of interest exceeded uptake in the corresponding contralateral side. The sensitivity, specificity, and accuracy of the study using this criterion were 86%, 12%, and 34%, respectively. When interpreted in conjunction with sulfur colloid marrow images, studies were considered positive for infection when uptake in the region of interest on leukocyte and marrow images was spatially incongruent. The sensitivity, specificity, and accuracy of this dual tracer modality were 100%, 94%, and 96%, respectively. Three patients with infection and abnormal leukocyte/marrow images underwent repeat imaging after appropriate therapy. Images were interpreted as normal in two of them; both were infection free at subsequent surgery. Images of the third patient were interpreted as consistent with persistent infection, and operative cultures grew out Staphylococcus aureus. In summary, combined leukocyte/marrow imaging is a highly accurate method for diagnosing musculoskeletal infection and overcomes certain inherent limitations of labeled leukocyte imaging alone.

There is no consensus or a uniform technique for measuring gastric emptying and numerous modalities have been reported. We report here the results obtained using a modification of the published techniques for the simultaneous measurement of duodenogastric reflux and gastric emptying utilizing simultaneously the recently developed radiopharmaceutical 97Ru-DISIDA, intravenously, and the oral administration of 99Tcm-sulphur colloid incorporated in a 'solid' test meal.

Lymphoseek is a receptor-binding radiopharmaceutical specifically designed for sentinel lymph node (SLN) mapping. We conducted a clinical trial which measured the injection site clearance and sentinel lymph node accumulation after a single intradermal injection of Lymphoseek or unfiltered [(99m)Tc]sulfur colloid (TcSC) using a "2-day" protocol for SLN mapping of breast cancer. Eleven patients with breast cancer participated in this study. Five patients received an intradermal administration of 1.0 nmol of (99m)Tc-labeled Lymphoseek; SLN mapping was performed on four subjects within 19 to 27 h. Six subjects received an intradermal administration of TcSC; SLN mapping was performed on five subjects within 18 to 26 h. Lymphoseek exhibited a significantly (P

The characterization of focally spared areas in a fatty liver may at times be problematic. This report illustrates the unique diagnostic role that combined xenon-133/technetium-99m sulfur colloid scintigraphy can play in such cases.

Eleven patients with proven primary bone tumour (five Ewing sarcomas, six osteosarcomas) and two cases of metastatic bone involvement (primary other than bone) were investigated with 99mTc-phytate and 99mTc-sulphur colloid to compare the behaviour of the two radiopharmaceuticals at the tumour site. After intravenous administration of the respective radiopharmaceutical, imaging of the tumour site and its contralateral part was carried out at 15 min and 1 h intervals. The data were stored in our computer. Bone scanning was also carried out in all patients. 99mTc-phytate uptake was observed at the tumour site in ten cases. The 99mTc-sulphur colloid study revealed sparse or no significant uptake in eight cases. In two patients, with osteosarcoma 99mTc-sulphur colloid investigation showed uptake at the primary tumour site. However, the distribution pattern is different from that of 99mTc-phytate. No significant uptake of either 99mTc-phytate or 99mTc-sulphur colloid was observed in the two patients with metastatic skeletal disease. It may be concluded that the unusual accumulation of 99mTc-phytate at the tumour site is not due to any generalized reticuloendothelial phenomenon and that the radiopharmaceutical itself is responsible for this.

Radiolabeling of Ivalon (polyvinyl alcohol sponge) particles permits localization of injected particles during embolization through the use of a portable gamma camera and provides a means to prevent potentially fatal complications such as pulmonary embolization. A more efficient technique of labeling Ivalon particles with technetium-99m sulfur colloid was developed. An increase in labeling efficiency allowed more accurate determination of the distribution of injected Ivalon particles. Scanning electron microscopy demonstrated the stability of the Ivalon particles during this new labeling process. Two patients with arteriovenous malformations underwent therapeutic embolization with radiolabeled Ivalon particles; gamma camera imaging of the lesion and chest was performed throughout the procedure.