Pancreatic neuroendocrine tumor detected by technetium-99m methoxy-2-isobutylisonitrile single photon emission computed tomography/computed tomography:A case report

BACKGROUND Pancreatic neuroendocrine tumors(NETs)account for about 1%–2%of pancreatic tumors and about 8%of all NETs.Computed tomography(CT),magnetic resonance imaging,and endoscopic ultrasound are common imaging modalities for the diagnosis of pancreatic NETs.Furthermore,somatostatin receptor imaging is of great value for diagnosing pancreatic NETs.Herein,we report the efficacy of technetium-99m methoxy-2-isobutylisonitrile(99mTc-MIBI)single photon emission CT(SPECT)/CT for detecting pancreatic NETs.CASE SUMMARY A 57-year-old woman presented to our hospital with a 1-d history of persistent upper abdominal distending pain.The distending pain in the upper abdomen was aggravated after eating,with nausea and retching.Routine blood test results showed a high neutrophil percentage,low leukomonocyte and monocyte percentages,and low leukomonocyte and eosinophil counts.Amylase,liver and kidney function,and tumor markers alpha-fetoprotein,carcinoembryonic antigen,and cancer antigen(CA)125,CA72-4,CA19-9,and CA153 were normal.Abdominal CT showed a mass,with multiple calcifications between the pancreas and the spleen.The boundary between the mass and the pancreas and spleen was poorly defined.Contrast-enhanced CT revealed that the upper abdominal mass was unevenly and gradually enhanced.99mTc-MIBI SPECT/CT revealed that a focal radioactive concentration,with mild radioactive concentration extending into the upper abdominal mass,was present at the pancreatic body and tail.The 99mTc-MIBI SPECT/CT manifestations were consistent with the final pathological diagnosis of pancreatic NET.CONCLUSION 99mTc-MIBI SPECT/CT appears to be a valuable tool for detecting pancreatic NETs.

Quantification of Tc-99m-ethyl cysteinate dimer brain single photon emission computed tomography images using statistical probabilistic brain atlas in depressive end-stage renal disease patients:Correlation with disease severity and symptom factors

This study adapted a statistical probabilistic anatomical map of the brain for single photon emission computed tomography images of depressive end-stage renal disease patients. This research aimed to investigate the relationship between symptom clusters, disease severity, and cerebral blood flow. Twenty-seven patients （16 males, 11 females） with stages 4 and 5 end-stage renal disease were enrolled, along with 25 healthy controls. All patients underwent depressive mood assessment and brain single photon emission computed tomography. The statistical probabilistic anatomical map images were used to calculate the brain single photon emission computed tomography counts. Asymmetric index was acquired and Pearson correlation analysis was performed to analyze the correlation between symptom factors, severity, and regional cerebral blood flow. The depression factors of the Hamilton Depression Rating Scale showed a negative correlation with cerebral blood flow in the left amygdale. The insomnia factor showed negative correlations with cerebral blood flow in the left amygdala, right superior frontal gyrus, right middle frontal gyrus, and left middle frontal gyrus. The anxiety factor showed a positive correlation with cerebral glucose metabolism in the cerebellar vermis and a negative correlation with cerebral glucose metabolism in the left globus pailidus, right inferior frontal gyrus, both temporal poles, and left parahippocampus. The overall depression severity （total scores of Hamilton Depression Rating Scale） was negatively correlated with the statistical probabilistic anatomical map results in the left amygdala and right inferior frontal gyrus. In conclusion, our results demonstrated that the disease severity and extent of cerebral blood flow quantified by a probabilistic brain atlas was related to various brain areas in terms of the overall severity and symptom factors in end-stage renal disease patients.

Same day yttrium-90 radioembolization with single photon emission computed tomography/computed tomography: An opportunity to improve care during the COVID-19 pandemic and beyond

BACKGROUND The coronavirus disease 2019(COVID-19)pandemic has made it more challenging for patients to undergo yttrium-90(Y-90)radioembolization(RE).Same day Y-90 RE provides an opportunity to minimize logistical challenges and infection risk associated with COVID-19,thus improving patient access.AIM To describe the use of same day Y-90 RE with routine single photon emission computed tomography/computed tomography(SPECT/CT)in order to optimize therapy.METHODS All patients were selected for Y-90 RE through a multidisciplinary tumor board,and were screened and tested for COVID-19 infection per institutional protocol.A same day procedure was developed,consisting of angiography,imaging,and Y-90 resin particle delivery.Routine SPECT/CT after technetium-99m macroaggregated albumin(Tc-99m MAA)administration was performed for assessment of arterial supply,personalized dosimetry,and extrahepatic activity.Post-treatment Y-90 bremsstrahlung SPECT/CT was performed for confirmation of particle delivery,by utilization of energy windowing to limit signal from previously administered Tc-99m MAA particles.RESULTS A total of 14 patients underwent same day Y-90 RE between March and June 2020.Mean lung shunt fraction was 6.13%(range 3.5%-13.1%).Y-90 RE was performed for a single lesion in 7 patients,while the remaining 7 patients had treatment of multifocal lesions.The largest lesion measured 8.3 cm.All patients tolerated the procedure well and were discharged the same day.CONCLUSION Same day Y-90 RE with resin-based microspheres is feasible,and provides an opportunity to mitigate infection risk and logistical challenges associated with the COVID-19 pandemic and beyond.We recommend consideration of SPECT/CT,especially among patients with complex malignancies,for the potential to improve outcomes and eligibility of patients to undergo same day Y-90 RE.

Deep brain stimulation of the subthalamic nucleus treats Parkinson's disease through enhancing metabolic activity of the corpus striatum Verification by single photon emission computed tomography and positron emission tomography

BACKGROUND： Subthalamic nucleus deep brain stimulation （STN DBS） for Parkinson＇s disease （PD） has achieved good effects, but to date the mechanism of STN DBS remains poorly understood STN DBS may increase dopamine levels or metabolic activity of the corpus striatum. OBJECTIVE： To validate the effects of STN DBS on dopamine metabolism and glucose metabolism in the corpus striatum of hemiparkinsonian monkeys using single photon emission computed tomography （SPECT） and position emission tomography （PET）. DESIGN, TIME AND SET＇rING： A controlled animal study was performed at the Neurosurgery Laboratory, Changhai Hospital of the Second Military Medical University of Chinese PLA between January 2004 and December 2007. METHODS： Hemiparkinsonism was induced in adult Rhesus Macaque monkeys, which exhibit similar characteristics of PD in humans, through unilateral internal carotid artery infusion of 1-methy-4-phenyl-1, 2, 3, 6-tetrahydropyrindine. Following model establishment, stimulation electrodes were implanted in the right STN, and chronic high-frequency stimulation （60 μs pulse width, 130 Hz frequency, and 1.5-2.0 V pressure） was performed. MAIN OUTCOME MEASURES： The changes in dopamine transporter （DAT）, D2 receptor （D2R）, and glucose metabolism in the corpus striatum following STN DBS were observed using SPECT and PET. RESULTS： SPECT examination showed that DAT specific binding in the right corpus striatum was increased at 3 months after DBS compared with prior to stimulation, and D2R specific binding in the right corpus striatum gradually decreased near levels on the left （non-electrode-implanted） side within 3 months after DBS. PET examination showed that the glucose metabolism in the right corpus striatum was markedly increased at 3 months after effective DBS. Hemiparkinsonism monkeys showed improved left limb rigidity, increased activities, and stable gait under chronic high-frequency stimulation. CONCLUSION： STN DBS increased striatal DAT, decreased D2R, and enhanced glucose metabolism, suggesting that chronic, high-frequency STN stimulation enhanced the metabolic activity of the corpus striatum, a mechanism for improving the PD symptoms of hemiparkinsonian monkeys.

Positron emission computed tomography/single photon emission computed tomography in Parkinson disease

Parkinson disease(PD)is the second-most common neurodegenerative disorder.Its main pathological mechanism is the selective degeneration and deletion of dopaminergic neurons in the dense part of the substantia nigra and the damage of dopaminergic neurons caused by the abnormal deposition of a Lewy body,leading to a decreased dopamine level.Positron emission computed tomography(PET)/single photon emission computed tomography(SPECT)is a molecular imaging technology that can directly or indirectly reflect changes in molecular levels by using a specific tracer.With the research and development on the tracers of related enzymes for labeling dopamine transporter and dopamine receptor and for being involved in dopamine formation,this imaging technology has been applied to all aspects of PD research.It not only contributes to clinical work but also provides an important theoretical basis for exploring the pathological mechanism of PD at a molecular level.Therefore,this review discusses the application value of PET/SPECT in PD in terms of early diagnosis,disease severity evaluation,clinical manifestations,differential diagnosis,and pathological mechanism.

Evaluating the Effectiveness of Electro-Acupuncture as A Treatment for Childhood Autism Using Single Photon Emission Computed Tomography

Objective：To explore the effectiveness of electro-acupuncture（EA）in the treatment of childhood autism（CA）and evaluate its effectiveness using single photon emission computed tomography（SPECT）.Methods：A total of 55 CA patients（4.52±2.73 years）were enrolled in this study.All patients received EA treatments and were examined by SPECT before and after treatments.Results：Following treatment,the intracerebral multiple focal radioactivity distribution defect areas of CA patients were observed to be partially filled.Specifically,significant differences in the ratios of regional cerebral blood flow and global cerebral blood flow before（Fb）and after（Fe）EA treatment in different lesions were observed（in the left prefrontal cortex,t=5.01,P〈0.01;in the right prefrontal cortex,t=2.32,P〈0.05;in the left temporal lobe,t=4.54,P〈0.01;in the right temporal lobe,t=2.90,P〈0.05;in the left Broca’s area,t=5.82,P〈0.01）.After EA treatment,the patients exhibited symptomatic relief.Conclusion：EA is useful to treat CA and SPECT can be used to evaluate the effectiveness of this treatment.

Diffusion-weighted magnetic resonance imaging with short T1 inversion recovery-echo planar imaging combined with dual-head coincidence single photon emission computed tomography for diagnosing solitary pulmonary nodule

Positron emission tomography （PET） using 18F-fluorodeoxyglucose （FDG） has not been widely used in China for expensive cost （$1200）. Dual-head coincidence single photon emission computed tomography （DHC-SPECT） can depict many of the lesions depicted with a PET scanner in the lungs, which is used in place of PET-CT for discriminating malignant from benign pulmonary nodules in many studies. However, DHC-SPECT has inevitable false-negative results because the sensitivity for small lesions less than 2.0 cm is limited, and has high false-positive rate for active inflammatory nodules. Furthermore,DHC-SPECT also has a considerably higher cost （$300 in China） than other imaging examination.

Correlations of single photon emission computed tomography joints scan and bone metabolic markers in active rheumatoid arthritis

Objective To explore the correlation between quantitative value of joint bone scan by single photon emission computed tomography(SPECT)and serum bone metabolic markers in patients with active rheumatoid arthritis(RA).Methods Clinical data of 60 newly diagnosed RA patients were retrospectively collected in Department

Regional cerebral blood flow imaging assessment of brain function reconstruction in elderly hemiplegia patients by body weight support treadmill training

The mechanism underlying body weight support treadmill training in elderly hemiplegic stroke patients is largely unknown. This study aimed to elucidate the changes of cortical blood flow in seven elderly patients with post-stroke hemiplegia before and after body weight support treadmill training by semi-quantitative analysis of regional cerebral blood flow assessed by single photon emission computed tomography. Body weight support treadmill training for 6 months was effective in improving cerebral blood flow and promoting the walking speed and balance recovery in elderly patients with post-stroke hemiplegia.

Rheumatoid arthritis: Nuclear medicine state-of-the-art imaging

Rheumatoid arthritis(RA)is an autoimmune disease,which is associated with systemic and chronic inflammation of the joints,resulting in synovitis and pannus formation.For several decades,the assessment of RA has been limited to conventional radiography,assisting in the diagnosis and monitoring of disease.Nevertheless,conventional radiography has poor sensitivity in the detection of the inflammatory process that happens in the initial stages of RA.In the past years,new drugs that significantly decrease the progression of RA have allowed a more efficient treatment.Nuclear Medicine provides functional assessment of physiological processes and therefore has significant potential for timely diagnosis and adequate follow-up of RA.Several single photon emission computed tomography(SPECT)and positron emission tomography(PET)radiopharmaceuti-cals have been developed and applied in this field.The use of hybrid imaging,which permits computed tomography(CT)and nuclear medicine data to be acquired and fused,has increased even more the diagnostic accuracy of Nuclear Medicine by providing anatomical localization in SPECT/CT and PET/CT studies.More recently,fusion of PET with magnetic resonance imaging(PET/MRI)was introduced in some centers and demonstrated great potential.In this article,we will review studies that have been published using Nuclear Medicine for RA and examine key topics in the area.

Effects of intravascular laser phototherapy on delayed neurological sequelae after carbon monoxide intoxication as evaluated by brain perfusion imaging:A case report and review of the literature

BACKGROUND Delayed neurological sequelae(DNS)caused by carbon monoxide(CO)intoxication poses considerable treatment challenges for clinical practitioners.In this report,we used nuclear medicine imaging and the Mini-Mental State Examination(MMSE)to evaluate the effectiveness of intravascular laser irradiation of blood(ILIB)therapy for the management of DNS.CASE SUMMARY A 51-year-old woman presented to our medical center experiencing progressive bradykinesia,rigidity of limbs,gait disturbance,and cognitive impairment.Based on her neurological deficits,laboratory tests and imaging findings,the patient was diagnosed with delayed neurological sequelae of CO intoxication.She received intensive rehabilitation and ILIB therapy during 30 sessions over 2 mo after diagnosis.Brain single-photon emission computed tomography was performed both prior to and after ILIB therapy.The original hypoperfusion area in bilateral striata,bilateral frontal lobe,right parietal lobe,and bilateral cerebellum showed considerable improvement after completion of therapy.The patient’s MMSE score also increased markedly from 6/30 to 25/30.Symptoms of DNS became barely detectable,and the woman was able to carry out her daily living activities independently.CONCLUSION ILIB therapy could facilitate recovery from delayed neurological sequelae in patients with CO intoxication,as demonstrated by improved cerebral blood flow and functional outcomes in our patient.

Therapeutic Effects of Tongxinluo Capsule(通心络胶囊) on Patients with Acute Small Oerebral Infarction and Its Influence on SPECT Brain Periusion Image

Objective: To investigate the influence of Tongxinluo capsule (TXL,通心络胶囊) on regional cerebral blood flow (rCBF) with 99mTc-ECD single photon emission computed tomography (SPECT) brain perfusion imaging, and to observe the therapeutic effects of TXL on acute small cerebral infarction (ASCI). Methods: Thirty-four patients with ASCI were enrolled and randomly divided into two groups: the control group (n = 17) was treated with the conventional treatment, i.e. 1. Og of Citicoline added into 300 ml normal saline for intravenous dripping daily for 2 weeks and 0. 8 g of Piracetam taken three times a day orally for 4 weeks, and the treatment group (n = 17) was treated additionally with 4 TXL capsules three times a day for 4 weeks besides the conventional treatment. The 99mTc-ECD SPECT brain perfusion imaging was performed before and after treatment to observe the change of rCBF, and the neurological deficit was evaluated by Edinburgh-Scandinavia stroke scale (SSS) scores and Barthel index (Bl) at the same time. Results: After treatment, the rCBF in the treatment group was significantly improved (P<0. 01), while that in the control group remained unchanged, with the comparison of the rCBF in the two groups after treatment showing significant difference (P<0.01). In addition, the SSS score was significantly lower and Bl significantly higher in the treatment group than those in the control group respectively after treatment. Conclusion: TXL could effectively improve rCBF and lessen the neurological deficit symptoms in patients with ASCI.

Progress in the application of molecular imaging inpsychiatric disorders

Psychiatric disorders have always attracted a lot of attention from researchers due to the difficulties in their diagnoses and treatments.Molecular imaging,as an emerging technology,has played an important role in the researchers of various diseases.In recent years,molecular imaging techniques including magnetic resonance spectroscopy,nuclear medicine imaging,and fluorescence imaging have been widely used in the study of psychiatric disorders.This review will briefly summarize the progression of molecular imaging in psychiatric disorders.

Regional cerebral blood flow in children with autism spectrum disorders： a quantitative 99mTc-ECD brain SPECT study with statistical parametric mapping evaluation

Background Autism spectrum disorders （ASD）, which include autism, asperger syndrome （AS） and pervasive developmental disorder-not otherwise specified （PDD-NOS）, are devastating neurodevelopmental disorders of childhood resulting in deficits in social interaction, repetitive patterns of behaviors, and restricted interests and activities. Single photon emission computed tomography （SPECT） is a common technique used to measure regional cerebral blood flow （rCBF）. Several studies have measured rCBF in children with ASD using SPECT, however, findings are discordant. In addition, the majority of subjects used in these studies were autistic. In this study, we aimed to investigate changes in rCBF in children with ASD using SPECT.Methods A Technetium-99m-ethyl cysteinate dimmer （99mTc-ECD） brain SPECT study was performed on an ASD group consisting of 23 children （3 girls and 20 boys; mean age （7.2±3.0） years） who were diagnosed according to Diagnostic and Statistical Manual of Mental Disorders, 4th edition （DSM-Ⅳ） criteria and an age-matched control group with 8children （1 girl and 7 boys, mean age （5.5±2.4） years）. Image data were evaluated with Statistical Parametric Mapping,5th version （SPM5）. A Student＇s t test for unpaired data was used to compare rCBF and asymmetry in the autism and corresponding control group. The covariance analysis, taking age as covariance, was performed between the ASD and control group.Results There was a significant reduction in rCBF in the bilateral frontal lobe （frontal poles, arcula frontal gyrus） and the bilateral basal ganglia in the autism group, and a reduction in the bilateral frontal, temporal, parietal, legumina nucleus and cerebellum in the AS group compared to the control. In addition, asymmetry of hemispheric hypoperfusion in the ASD group was observed. Inner-group comparison analysis revealed that rCBF decreased significantly in the bilateral frontal lobe （42.7%）, basal nucleus （24.9%） and temporal lobe （22.8%） in the autism group, and in the bilateral cerebellum （22.8%）, basal nucleus （19.3%） and right thalamencephalon （16.6%）in the AS group （P ＜0.05）.Conclusions The decrease in rCBF in ASD is a global event, which involves the bilateral frontal, temporal, limbic system and basal ganglias. Asymmetry of hemispheric hypoperfusion was more obvious in the AS group than the autism group, which indicates a different neurobiological mechanism from that of autism.

The combined therapeutic effects of ^(131)iodinelabeled multifunctional copper sulfide-loaded microspheres in treating breast cancer

Compared to conventional cancer treatment, combination therapy based on well-designed nanoscale platforms may offer an opportunity to eliminate tumors and reduce recurrence and metastasis.In this study, we prepared multifunctional microspheres loading ^(131)I-labeled hollow copper sulfide nanoparticles and paclitaxel( ^(131)I-HCu SNPs-MS-PTX) for imaging and therapeutics of W256/B breast tumors in rats.18 F-fluordeoxyglucose(18 F-FDG) positron emission tomography/computed tomography(PET/CT) imaging detected that the expansion of the tumor volume was delayed(Po0.05) following intra-tumoral(i.t.) injection with ^(131)I-HCu SNPs-MS-PTX plus near-infrared(NIR) irradiation. The immunohistochemical analysis further confirmed the anti-tumor effect. The single photon emission computed tomography(SPECT)/photoacoustic imaging mediated by ^(131)I-HCu SNPs-MS-PTX demonstrated that microspheres were mainly distributed in the tumors with a relatively low distribution in other organs. Our results revealed that ^(131)I-HCu SNPs-MS-PTX offered combined photothermal, chemo-and radio-therapies, eliminating tumors at a relatively low dose, as well as allowing SPECT/CT and photoacoustic imaging monitoring of distribution of the injected agents non-invasively. The copper sulfide-loaded microspheres, ^(131)I-HCu SNPs-MS-PTX, can serve as a versatile theranostic agent in an orthotopic breast cancer model.

^(188)Re-LABELED HYPERBRANCHED POLYSULFONAMINE AS A ROBUST TOOL FOR TARGETED CANCER DIAGNOSIS AND RADIOIMMUNOTHERAPY

Hyperbranched polysulfonamine （HPSA） is a promising biomaterial due to its highly branched spherical architecture and efficient intracellular translocation. To realize the fianctionalization of HPSA, both N-succinimidyl 3-（2- pyridyldithio） propionate （SPDP） for tethering the human-mouse chimeric monoclonal antibody CH12 and N-hydroxy succinimidyl S-acetylmercaptoacetyltriglycinate （NHS-MAG3） for labeling 188Re were sequentially grafted onto the primary amine terminals of HPSA via covalent linkages, attaining the SPDP-HPSA-MAG3 intermediate. In order to reserve the structural integrity of CH12, the fragment crystallizable （Fc） region was also processed by oxidation of oligosaccharide moieties with sodium periodate and then reacted with N-（κ-maleimidoundecanoic acid） hydrazide （KMUH）. After chelating 188Re with MAG3 group, the SPDP was reduced to PDP and connected onto the maleinimide group at the Fc region. As a result, both the epidermal growth factor receptor viii （EGFRvIII） targeted monoclonal antibody CH12 and the radionuclide 188Re were conjugated to the HPSA-based vehicles, forming the 188Re-labeled and CH12-tethered HPSA （CH12-HPSA- 188Re）. The molecular weight and in vitro stability of CH12-HPSA-188Re were evaluated by gel electrophoresis and paper chromatography. On one hand, the CH12-HPSA-188Re could specifically bind to the EGFRvlII-positive human hepatocarcinoma cells in vitro. On the other hand, it could also target at the tumor tissue of nude mice in vivo. Hence, the CH12-HPSA-188Re could effectively target at the human hepatocarcinoma and facilitate the tumor detection and targeted radioimmunotherapy.

Image Reconstructions from Limit Views and Angle Coverage Data for a Stationary Multi-Pinhole SPECT System

The goal of this paper is to investigate different reconstruction methods for solving the limited angle problem in reconstructing the projection data from a stationary multi-pinhole system based on a three-head clinical single photon emission computed tomography （SPECT） camera. Three iterative recon- struction approaches were studied including maximum likelihood expectation maximization （MLEM）, maximum a posteriori expectation maximization （MAPEM） with a smoothing prior, and an alternating optimization schemes from MLEM and total variation （TV） optimization. A three-headed multipinhole SPECT was simulated with apertures of nine 1-mm pinholes each, and covered scanning volume of 6-mm diameter. The reconstructions were optimized for various iterations based on visual inspections, and finally 20 iterations were applied for each method. For both MLEM-TV and MAPEM-TV, various initial reconstructions before TV optimization were studied. The smoothing parameter for MAPEM and the gradient descent constant for TV were also investigated through visual comparison. The preliminary results showed the 3 reconstruction methods generated compatible images, and can restore the images from projection data suffering limited angular sampling. However, MLEM was noisy for low-count and highly limited angle data, and thus suitable smoothing in MAPEM alleviated this problem, initial reconstructions were necessary for better edge enhancement in TV. The conclusion is that TV might be potential in producing more edge-enhanced images if all parameters were optimized.

Quantitative Accuracy Assessment and Optimization of SPECT Geometrical Calibration

Accurate geometrical calibration is critical to obtaining high resolution and artifact free reconstructed images for modern animal single photon emission computed tomography （SPECT） systems. Although there have been many published works on the calibration of various SPECT systems, few studies have been done to evaluate the efficacy of the proposed calibration methods in a quantitative manner. This paper presents a numerical method to assess both the uniqueness and the quantitative accuracy of SPECT calibration, which is based on analyzing the singular value decomposition （SVD） components of the Jacobian matrix from a least-square cost function of the calibration. The proposed method is firstly validated by applying it to the calibration of a single pinhole SPECT system and comparing the results with those derived using a published method, and is then used to optimize the calibration setup for a slit-slat SPECT system. With the proposed method, a minimum required number of point source projections to achieve the desired calibration accuracy can be estimated and used as figure-of-merit to evaluate the goodness of a calibration setup. An inverse-square relationship between the calibration accuracy and the number of sampled projections is revealed. Optimal calibration setup is determined through an exhaustive search among all the pos- sibilities of point source arrangements under certain conditions. We demonstrate that for the studied system, the best calibration accuracy is achieved by arranging the point source over the edge of FOV with evenly- spaced angular positions. Point source experiments were conducted to validate the proposed method.

Differentiation of radiation necrosis from glioblastoma recurrence after radiotherapy

The standard treatment of glioblastoma,the most common type of primary-brain-tumor,involves radiotherapy with concomitant temozolomide chemotherapy.A patient with glioblastoma,post radiotherapy developed magnatic resonance imaging(MRI)changes consistent with either radiation-induced tumor necrosis or tumor recurrence.Perfusion MRI was suggestive of radiation necrosis,but magnetic resonance spectroscopy and 99mTc-Tetrofosmin single photon emission computed tomography was indicative of tumor recurrence.Positron emission tomography scan was not available.Tumor recurrence was documented by biopsy.Several advanced imaging methods are available to differentiate tumor recurrence from radiation necrosis in glioblastoma patients.However,in inconclusive cases,brain biopsy should be performed for definite diagnosis.