Direct technetium-99m labeling of anti-hepatoma monoclonal antibody fragment:a radioimmunoconjugate for hepatocellular carcinoma imaging

AIM To directly radiolabel an anti-hepatomamAb fragment HAb18 F（ab’）2 with 99mTc bystannous-reduced method,and assess thestability,biodistribution and radioimmun-oimaging（RⅡ）.METHODS Immunoreactive fraction wasdetermined according to Lindmo’s method.Ellman’s reagent was used to determine thenumber of thiols in the reduced F（ab’）2.Labelingefficiency and homogeneity were measured bypaper chromatography,sodium dodecylsulphatepolyacrylamide gel electrophoresis（SDS-PAGE）and autoradiography.Challenge assay involvedthe incubation of aliquots of labeled antibody inethylenediaminetetraacetate（ EDTA ）and L-cysteine（L-cys）solutions with different molarratio at 37℃ for 1h,respectively.Investigationsin vivo utilized nude mice bearing humanhepatocellular carcinoma（HHCC）xenograftswith gamma camera imaging and tissuebiodistribution studies at regular intervals.RESULTS The labeling procedure was finishedwithin 1.5 h compared with the'pretinning'method which would take at least 21h.In vitrostudies demonstrated that the radiolabeled mAbfragment was homogeneous and retained itsimmunoreactivity.Challenge studies indicatedthat 99mTc-labeled HAb18 F（ab’）2 in EDTA is morestable than in L-cys.Imaging and biodistribution showed a significant tumor uptake at 24 h post-injection of 99mTc-labeled HAb18 F（ab’）2.Theblood,kidney,liver and tumor uptakes at 24hwere 0.56±0.09,56.45±11.36,1.43±0.27 and6.57±3.01（%ID/g）,respectively.CONCLUSION 99mTc-HAb18 F（ab’）2 conjugateprepared by this direct method appears to be aneffective way to detect hepatoma in nude micemodel.

Effect of Technetium-99 Conjugated with Methylene Diphosphonate on IgM-RF,IgG-RF and IgA-RF

To explore the effect of technetium-99 conjugated with methylene diphosphonate ( 99 Tc-MDP) on IgM-RF, IgG-RF and IgA-RF (RFs), 47 cases were selected for study, including 33 patients with rheumatoid arthritis (RA) and 15 patients with joint pain/arthritis. After 99 Tc-MDP for drips model being given to the patients by intravenous drip 0.2 g daily for 5 days, the injection A and B models of 99 Tc-MDP were used to the patients by intravenous injection one set daily for 10 days, that was one course of treatment. The next course started after 10 days. Each case used it from 2 to 4 courses of treatment. The RFs in serum were determined by the method of enzyme-linked immunoabsorption assay (ELISA) before and after 2 and 4 courses of treatment. In the patients with RA, the concentrations of IgM-RF were 296.2±108.4 IU/ml, 189.5±92.3 IU/ml and 107.8±72.5 IU/ml; the concentrations of IgG-RF were 325.6±126.2 IU/ml, 209.7±98.2 IU/ml and 160.2±80.8 IU/ml; the concentrations of IgA-RF were 330.4±136.3 IU/ml, 210.7±89.2 IU/ml and 148.8±72.2 IU/ml before and after 2 and 4 courses of treatment, respectively. The concentrations of the above RFs were significantly lower after 2 and 4 courses than those before treatment ( P <0.05 and P <0.01). There was no significant difference in RFs concentrations in the patients with joint pain/arthritis before and after use of 99 Tc-MDP. In the patients with positive RFs before treatment, the RFs concentrations were decreased significantly after 2 and 4 courses of treatment ( P <0.05 and P <0.01). There was no obvious change of RFs concentrations in the patients with negative RFs after treatment of 99 Tc-MDP. It was concluded that 99 Tc-MDP could obviously reduce the abnormally high concentrations of RFs, but not influence the normal RFs, which indicated that 99 Tc-MDP has an important effect on controlling the activities of RA.

Anti-sense oligonucleotide labeled with technetium-99m using hydrazinonictinamide derivative and N-hydroxysuccinimidyl S-acetylmercaptoacetyltriglycline: A comparison of radiochemical behaviors and biological properties

AIM:To explore and compare the radiochemical behavior and biological property of anti-sense oligonuc-leotide (ASON) labeled with technetium-99m using N-hydroxysuccinimidyl S-acetylmercaptoacetyltriglycl ine (NHS-MAG3) and hydrazinonictinamide derivative (HYNIC). METHODS:After HYNIC and NHS-MAG3 were synthesized, ASON was labeled with technetium-99m using HYNIC and NHS-MAG3 as a bifunctional chelator. The in vivo and in vitro stability, binding rates of labeled compounds to serum albumen, biodistribution of 99mTc-MAG3-ASON and 99mTc-HYNIC-ASON in BALB/C mouse and its HT29 tumor cellular uptake were compared. RESULTS:The labeling efficiency and stability of 99mTc-MAG3-ASON were significantly higher than those of 99mTc-HYNIC-ASON (P = 0.02, and P = 0.03, respectively). 99mTc-MAG3-ASON had a significantly lower rate of binding to serum albumen than 99mTc-HYNIC-ASON (P < 0.05). In contrast to 99mTc-HYNIC-ASON, the biodistribution of 99mTc-MAG3-ASON was significantly lower in blood, heart, liver and stomach (P < 0.05), slightly lower in intestines and spleen (P > 0.05) and significantly higher in lung and kidney (P < 0.05). The HT29 tumor cellular uptake rate of 99mTc-MAG3-ASON was significantly higher than that of 99mTc-HYNIC-ASON (P < 0.05). CONCLUSION:99mTc-MAG3-ASON shows superior radiochemical behaviors and biological properties than 99mTc-HYNIC-ASON. 99mTc-MAG3-ASON is a potential radiopharmaceutical agent for in vivo application.

Guava extract (Psidium guajava) alters the labelling of blood constituents with technetium-99m

Psidium guajava (guava) leaf is a phytotherapic used in folk medicine to treat gastrointestinal and respiratory dis-turbances and is used as anti-inflammatory medicine. In nuclear medicine, blood constituents (BC) are labelled with techne-tium-99m (99mTc) and used to image procedures. However, data have demonstrated that synthetic or natural drugs could modify the labelling of BC with 99mTc. The aim of this work was to evaluate the effects of aqueous extract of guava leaves on the labelling of BC with 99mTc. Blood samples of Wistar rats were incubated with different concentrations of guava extract and labelled with 99mTc after the percentage of incorporated radioactivity (%ATI) in BC was determined. The results suggest that aqueous guava extract could present antioxidant action and/or alters the membrane structures involved in ion transport into cells, thus decreasing the radiolabelling of BC with 99mTc. The data showed significant (P<0.05) alteration of ATI in BC from blood incubated with guava extract.

Technetium-99m-labeled macroaggregated albumin lung perfusion scan for diagnosis of hepatopulmonary syndrome: A prospective study comparing brain uptake and whole-body uptake

BACKGROUND Hepatopulmonary syndrome (HPS) is an arterial oxygenation defect induced by intrapulmonary vascular dilatation (IPVD) in the setting of liver disease and/or portal hypertension.This syndrome occurs most often in cirrhotic patients(4%-32%) and has been shown to be detrimental to functional status,quality of life,and survival.The diagnosis of HPS in the setting of liver disease and/or portal hypertension requires the demonstration of IPVD (i.e.,diffuse or localized abnormally dilated pulmonary capillaries and pulmonary and pleural arteriovenous communications) and arterial oxygenation defects,preferably by contrast-enhanced echocardiography and measurement of the alveolar-arterial oxygen gradient,respectively.AIM To compare brain and whole-body uptake of technetium for diagnosing HPS.METHODS Sixty-nine patients with chronic liver disease and/or portal hypertension were prospectively included.Brain uptake and whole-body uptake were calculated using the geometric mean of technetium counts in the brain and lungs and in the entire body and lungs,respectively.RESULTS Thirty-two (46%) patients had IPVD as detected by contrast-enhancedechocardiography.The demographics and clinical characteristics of the patients with and without IPVD were not significantly different with the exception of the creatinine level (0.71±0.18 mg/dL vs 0.83±0.23 mg/dL;P=0.041),alveolararterial oxygen gradient (23.2±13.3 mmHg vs 16.4±14.1 mmHg;P=0.043),and arterial partial pressure of oxygen (81.0±12.1 mmHg vs 90.1±12.8 mmHg;P=0.004).Whole-body uptake was significantly higher in patients with IPVD than in patients without IPVD (48.0%±6.1%vs 40.1%±8.1%;P=0.001).The area under the curve of whole-body uptake for detecting IPVD was significantly higher than that of brain uptake (0.75 vs 0.54;P=0.025).The optimal cut-off values of brain uptake and whole-body uptake for detecting IPVD were 5.7%and 42.5%,respectively,based on Youden’s index.The sensitivity,specificity,and accuracy of brain uptake> 5.7%and whole-body uptake> 42.5%for detecting IPVD were23%,89%,and 59%and 100%,52%,and 74%,respectively.CONCLUSION Whole-body uptake is superior to brain uptake for diagnosing HPS.

Leukocyte-technetium-99m uptake in Crohn's disease:Does it show subclinical disease?

AIM:To evaluate inflammatory activity in patients with Crohn's disease (CD) using technetium-99m-hexamethylpropyleneamine oxime (99mTc-HMPAO) granulocyte scintigraphy.METHODS: Twenty patients (7 male and 13 female) with CD and five healthy volunteers were selected for 99mTc-HMPAO granulocyte scintigraphy. The Crohn's Disease Activity Index (CDAI), blood tests and C-reactive protein (CRP) of each patient were performed 7 d before the scintigraphic images. The leukocytes were labeled according to the International Society of Radiolabeled Blood Elements (ISORBE) consensus protocol and the scintigraphic images, including single photon emission computed tomography, were obtained 30 min and 2 h after injection of the radiolabeled leukocytes.RESULTS:The labeling yield of the leukocytes with the lipophilic complex 99mTc-HMPAO was 55.0%±10%. Six of the 20 patients (30%) presented congruent results for the three parameters investigated (CDAI, Scintigraphic Index and CRP). On the other hand, 14 patients (70%) did not show congruent results. There was no significant correlation between the indices analyzed according to the Spearman test (P>0.05,n=20).CONCLUSION: The results suggest that 99mTc-HMPAO-labeled leukocyte scintigraphy could be important for determining inflammatory activity in CD even in the absence of clinical symptoms.

Technetium-99m-labeled annexin V imaging for detecting prosthetic joint infection in a rabbit model

Accurate and timely diagnosis of prosthetic joint infection is essential to initiate early treatment and achieve a favorable outcome. In this study, we used a rabbit model to assess the feasibility of technetium-99m-labeled annexin V for detecting prosthetic joint infection. Right knee arthroplasty was performed on 24 New Zealand rabbits. After surgery, methicillin-susceptible Staphylococcus aureus was intra-articularly injected to create a model of prosthetic joint infection （the infected group, n = 12）. Rabbits in the control group were injected with sterile saline （n= 12）. Seven and 21 days after surgery, technetium-99m-labeled annexin V imaging was per- formed in 6 rabbits of each group. Images were acquired 1 and 4 hours after injection of technetium-99m- labeled annexin V （150 MBq）. The operated-to-normal-knee activity ratios were calculated for quantitative ana- lysis. Seven days after surgery, increased technetium-99m-labeled annexin V uptake was observed in all cases. However, at 21 days a notable decrease was found in the control group, but not in the infected group. The operated-to-normal-knee activity ratios of the infected group were 1.84 ±0.29 in the early phase and 2.19 ±0.34 in the delay phase, both of which were significantly higher than those of the control group （P=0.03 and P=0.02）. The receiver operator characteristic curve analysis showed that the operated-to-normal-knee activity ratios of the delay phase at 21 days was the best indicator, with an accuracy of 80%. In conclusion, technetium- 99m-labeled annexin V imaging could effectively distinguish an infected prosthetic joint from an uninfected prosthetic joint in a rabbit model.

Quantitative Analysis of the Tomographic Technetium-99m MIBI (^(99m)Tc-MIBI) Myocardial Bullseye Display: Application to Diagnosis of Coronary Artery Disease

In this study, the 99mTc-MIBI myocardial bullseye display of 31 healthy persons and 34 patients with myocardial ischemia and 17 patients with myocardial infarction were analyzed quantitatively, and compared with the results of myocardial tomography analysis and qualitative bullseye analysis. The sensitivities of the three methods were 88.2%, 91.2 % and 94.1 % respectively (P>0.05),and the specificities were 93. 5%, 83, 9% and 83. 9% respectively (P<0.05).On the other hand, the quantitative analysis obviously outperformed the other two methods in the detection of ischemic segments of myocardium near infarction zone (P<0. 01). The quantitative analysis of 99mTc-MIBI myocardial bullseye (quantitative bullseye) was an objective, specific and sensitive method for diagnosis of coronary artery disease.

A NEW BIFUNCTIONAL CHELATING AGENT α,ε-N,N'-BIS(L-CYSTEINYL)-L-LYSINE FOR RADIOLABELLING OF MONOCLONAL ANTIBODIES WITH TECHNETIUM-99M

α,ε-N,N'-bis(L-cysteinyl)-L-lysine was synthesized and char- acterized for the first time.It was then employed as a bifunctional chelating agent to chelate technetium-99m and subsequently conjugated to fragment F(ab')_2 of anti-gastric tumor monoclonal antibody 3G9.The radiolabelled antibody was satisfactorily stable and immunoreactive.

Hepatic clearance measured with ^(99m)Tc-GSA single-photon emission computed tomography to estimate liver fibrosis

AIM: To evaluate the clinical utility of hepatic clearance(HC) measured with technetium-99m-diethylenetriaminepenta-acetic acid-galactosyl human serum albumin(99mTc-GSA) single-photon emission computed tomography(SPECT) to estimate the degree of liver fibrosis.METHODS:Seventy-eight consecutive patients who underwent initial hepatectomy due to hepatocellular carcinoma were enrolled in this study.Indocyanine green clearance(ICG R15),quantitative indices estimated by 99mTc-GSA[the receptor index(LHL15 and HH15)and HC via SPECT analysis],and conventional liver function tests were performed before hepatectomy.Correlations among the quantitative indices for liver functional reserve,conventional liver function tests,andthe degree of liver fibrosis were evaluated.RESULTS:The degree of liver fibrosis was correlated with ICG R15,HH15,LHL15,and HC.HC showed the best correlation with conventional liver function tests.According to multivariate analysis,HC and LHL15 were significant independent predictors of severe fibrosis.HC was the most valuable index for predicting severe fibrosis.CONCLUSION:HC measured with 99mTc-GSA SPECT is a reliable index for assessing liver fibrosis before hepatectomy.

Is there a role for Tc-99m (V) DMSA scintigraphy in ischemic colitis?

AIM: To evaluate the role of pentavalent Tc-99m dimercaptosuccinic acid [Tc-99m (V) DMSA] in the diagnosis of ischemic colitis. METHODS: Fourteen patients with endoscopically and histologically confirmed ischemic colitis were included in the study. Tc-99m (V) DMSA scintigraphy was performed within 2 d after colonoscopy. Images were considered positive when an area of increased activity was observed in the region of interest and negative when no abnormal tracer uptake was detected. RESULTS: In 3 out of the 14 patients, Tc-99m (V) DMSA images showed moderate activity in the bowel. The scintigraphic results corresponded with the endoscopic findings. In the other 11 patients, no abnormal tracer uptake was detected in the abdomen. CONCLUSION: Besides the limited number of patients, Tc-99m (V) DMSA could not be considered as a useful imaging modality for the evaluation of ischemic colitis.

LABELLING OF METALLOTHIONEIN WITH ^(99m)Tc

99mTc-labelled metallothionein (99mTc-MT) was prepared through both direct and transcomplexation labelling approaches. Buffer systems and a variety of other parameters in the direct labelling procedure were studied in detail. High radiolabelling yields of 93-96% and the specific radioactivity of 3.7 MB/μg were obtained under optimal conditions by the direct labelling method. The prepared 99mTc-MT was stable in vitro. The chelate-exchange kinetics of MT with 99mTc-glucohepatonate and 99mTc-citrate were also studied. Biodistribution and imaging studies showed that 99mTc-MT was accumulated in the animal kidneys at an exceptionally high level, indicating that 99mTc-MT might be a potential renal imaging agent.

Assessment of Warm and Cold Ischemia on Functions of the Operated Kidney with ^99mTc-DMSA in Renal Masses: A Prospective and Randomized Study

Objective: To examine the effect of warm and cold ischemia on functions of the operated kidney in cases with a normal contralateral kidney undergoing nephron sparing surgery. Methods: This study enrolled 40 patients with a normal contralateral kidney and without a renal function threatening risk factor, who were operated with NSS. The patients were randomized at admission. They were divided into 2 equal groups as warm and cold ischemia. An ice application for 10 minutes was done to cold ischemia group after clamping renal artery. Renal functions were evaluated with Technesium-99m-Dimercaptosuccinic Acid (DMSA) and serum creatinine at the preoperative and postoperative (day 1, day 15, month 6, and month 12) period. Statistical analysis was done with Mann Whitney U test, Wilcoxon Signed Rank test, and Fredman test. A p value below 0.05 was considered statistically significant. Results: There were no significant differences between the groups in terms of age, body mass index, ischemia time, tumor size, amount of hemorrhage, and procedure time. Both groups had a significantly higher DMSA uptake at the preoperative period compared with the postoperative period (postoperative day 1, day 15, month 6, and month 12) (p 0.001). However, both groups had similar DMSA uptake results at the postoperative period. Preoperative and postoperative creatinine levels were not significantly different from each other in both groups. Conclusion: Based on tumor localization, nephron sparing surgery without use of superficial cooling appears as a viable option for small renal masses.

Removal of Technetium (⁹⁹Tc) from Aqueous Waste by Manganese Oxide Nanoparticles Loaded into Activated Carbon

Technetium-99 is a radioactive isotope with a half-life of 2.13 × 105 year. 99Tc is a significant contaminant of concern to the world. For this reason, a detailed understanding of technetium chemistry is essential for the protecting the public and the environment especially after increasing the various applications and uses of isotopes in the medical practices. Therefore, treatment of waste increases prior to the safe discharge to the environment or the storage. The sorption of technetium in the form of pertechnetate on a nano manganese oxide loaded into activated carbon has been investigated. Nano manganese oxide (NMO) was synthesized from manganese chloride and potassium permanganate by co-precipitation and forming a new composite by loading a nanoparticle into a modified activated carbon by different ratios. Modifications of activated carbons using different concentrations of HNO3 (4 M, 6 M and 8 M) are used in prepared composites. Fourier transform infrared spectroscopy (FT-IR), X-Ray Diffraction (XRD) and Scanning Electron Microscope (SEM) were used to characterize the prepared composites. The adsorption of anions from low level radioactive aqueous waste was examined using batch technique. Different parameters affecting on the adsorption process were studied for the removal of . The results revealed that NMO/AC (4 M, 6 M and 8 M) has a high adsorption efficiency (93.57%, 90.3% and 90.3%) respectively compared to NMO and AC which have a lower adsorption efficiency (41% and 38.9%) respectively. Moreover, the adsorption isotherm belonged to Freundlich model, the adsorption data followed pseudo-second order model and the thermodynamic study indicated that the adsorption of on Nano-composites was an exothermic and spontaneous process.

Changes of Intestinal Permeability in Cholelithiasis Patients

In normal condition, intestine mucosa possesses barrier function. When the barrier function of intestine mucosa was damaged, intestinal bacteria, endotoxin, or other substances would enter blood. It is generally accepted that biliary bacteria origins from the intestine either via duodenal papilla or intestinal mucosa. In this study, we aimed to investigate the intestinal permeability changes of cholelithiasis patients to elucidate the possible pathogenesis of cholelithiasis.

Index of convexity:A novel liver function index using Tc-GSA scintigraphy

AIM:To investigate the clinical usefulness of a newly developed index,the "index of convexity(IOC)",for evaluating liver functional reserve using technetium99m-diethylenetriaminepentaacetic acid-galactosylhuman serum albumin(Tc-GSA scintigraphy).METHODS:In total,349 patients underwent Tc-GSA scintigraphy.Dynamic planner images were obtained,and time activity curves of the liver and heart were generated and analyzed.Our focus was on the convex shape of the liver accumulation curve.We developed a method for evaluating the extent of convexity and calculated an index that we named the IOC.Clearance index and receptor index were also calculated.The correlations between each GSA index with other liver function tests and liver histopathology were evaluated.RESULTS:Among the 3 indices generated by TcGSA,the IOC had the highest correlation with all other liver function tests(indocyanine green R15,albumin,prothrombin time,cholinesterase level,platelet count,and total bilirubin level).IOC can also differentiate between normal liver,chronic hepatitis,and liver cirrhosis with highest F ratio among GSA indices as determined by one-way analysis of variance.Receiver operating characteristic analysis demonstrated high diagnostic performance of IOC in the diagnosis of cirrhosis.CONCLUSION:IOC is a very simple and reliable index for assessing liver functional reserve,which may prove to be useful in combination with the indocyanine green test for preoperative assessment of hepatic resection.

Role of scintigraphy in inflammatory bowel disease

The diagnosis of inflammatory bowel disease(IBD) depends on direct endoscopic visualization of the colonic and ileal mucosa and the histological study of the obtained samples.Radiological and scintigraphic methods are mainly used as an adjunct to endoscopy.In this review,we focus on the diagnostic potential of nuclear medicine procedures.The value of all radiotracers is described with special reference to those with greater experience and more satisfactory results.Tc-99m hexamethylpropylene amine oxime white blood cells remain a widely acceptable scintigraphic method for the diagnosis of IBD,as well as for the evaluation of disease extension and severity.Recently,pentavalent Tc-99m dimercaptosuccinic acid has been recommended as an accurate variant and a complementary technique to endoscopy for the follow-up and assessment of disease activity.Positron emission tomography alone or with computed tomography using fluorine-18 fluorodeoxyglucose appears to be a promising method of measuring inflammation in IBD patients.

Simulating the Production of Medical Radioisotopes in a Fast Thorium-Cycle ADS with SERPENT

Radiopharmaceuticals are used in nuclear medicine for diagnostic or therapeutic acts. The short decay half-lives of medical radioisotopes, especially those used for diagnostics, imply that they should be produced continuously and transported as quickly as possible to the medical units where they are used. Neutron-rich medical radioisotopes are generally produced in research reactors, like technetium-99m, lutetium-177, holmium-166 and iodine-131. On the other hand, proton-rich radioisotopes are produced via reactions with charged particles from accelerators like fluorine-18, gallium-67, iodine-123 and thallium-201. Beside this, innovative nuclear reactors are advocated as solutions to the issues of nuclear waste production and proliferation threats. Fast neutron, thorium-cycle and accelerator-driven subcritical (ADS) reactors are some of the most promising of them, proposed as safer fuel breeders and “waste burners”. This article examines the use of a fast thorium-cycle ADS with liquid lead-bismuth eutectic coolant for the production of molybdenum-99/technetium-99m and lutetium-177. Burnup simulation has been made with the Monte-Carlo (MC) code SERPENT. It is demonstrated that MC codes can advantageously be used to determine the optimal irradiation time for a given radioisotope in a realistic reactor core. It is also shown that fast thorium-cycle ADS is an economical option for the production of medical radioisotopes.

Analysis of the successful clinical treatment of 140 patients with parathyroid adenoma:A retrospective study

BACKGROUND Parathyroid adenoma(PA) sometimes recurs after surgery,how to improve the surgical success rate of PA is the key to the treatment of this disease.AIM To investigate the clinical features,diagnosis,and surgical treatment of patients with PA.METHODS Patients who were pathologically confirmed with PA and had undergone surgery for the first time between January 2010 and December 2017 at the Beijing Shijitan Hospital affiliated to Capital Medical University were included in the study.The clinical features,localization diagnosis,and surgical treatment of these patients were analyzed.RESULTS Of the 140 patients,32 were male and 108 were female;132 cases had one adenoma,and 8 had two adenomas.In addition,114 cases had clinical symptoms,among which 51,28,23,8,and 4 had urinary system,skeletal system,digestive system,neuromuscular system,and neuropsychiatric symptoms,respectively,while 26 cases had no obvious symptoms.The median level of preoperative parathyroid hormone(PTH) was 201.0 pg/m L.The positive detection rate of technetium-99m sestamibi(Tc-99m MIBI) single-photon emission computed tomography/computed tomography(SPECT/CT),ultrasound examination,and the combined use of Tc-99m MIBI SPECT/CT and ultrasound examination was 92.9%,85.5%,and 96.4%,respectively.Open surgery was performed in all patients,and PTH was monitored during surgery.The success rate of surgery was 98.6%.After surgery,21 cases developed hypocalcemia,1 case developed temporary hoarseness,and 19 cases had transient hypoparathyroidism but there was no permanent hypoparathyroidism,postoperative hemorrhage,or hematoma in the surgical area.CONCLUSION For patients with clinically unexplained skeletal system,urinary system,and neuropsychiatric symptoms,the possibility of PA should be considered.Imaging examinations such as ultrasound and Tc-99m MIBI SPECT/CT could be integrated before surgery to obtain accurate localization diagnosis.Precise preoperative localization,intraoperative PTH monitoring,and delicate surgery to protect the integrity of the PA capsule ensure a minimally invasive and successful surgery.

Incidental Diagnosis of a Brown Tumor Mimicking Bone and Lung Metastasis during a Parathyroid Scintigraphy

We report herein a case of a 40-year-old male patient with chronic renal failure presenting a severe hyperparathyroidism with an elevation of parathormone level evaluated in nuclear medicine department for MIBI-Technetium-99m parathyroid scintigraphy. The parathyroid scintigraphy revealed the appearance of a preferential fixation of the MIBI-99mTc opposite the lower left pole of the thyroid and opposite the upper part of the right hemi thorax. A subsequent single-photon emission computed tomography-computed tomography focused on the cervico-thoracic region was performed and showed an ectopic parathyroid adenoma associated with an incidental brown tumor mimicking bone and lung metastases. Our case report confirms the usefulness of additional hybrid SPECT-CT imaging in the management of hyperparathyroidism.