Technetium-99m Methylene Diphosphonate Research Articles

Fast SPECT/CT planar bone imaging enabled by deep learning enhancement.

The application of deep learning methods in rapid bone scintigraphy is increasingly promising for minimizing the duration of SPECT examinations. Recent works showed several deep learning models based on simulated data for the synthesis of high-count bone scintigraphy images from low-count counterparts. Few studies have been conducted and validated on real clinical pairs due to the misalignment inherent in multiple scan procedures. To generate high quality whole-body bone images from 2× and 3× fast scans using deep learning based enhancement method. Seventy-six cases who underwent whole-body bone scans were enrolled in this prospective study. All patients went through a standard scan at a speed of 20cm/min, which followed by fast scans consisting of 2× and 3× accelerations at speeds of 40 and 60cm/min. A content-attention image restoration approach based on Residual-in-Residual Dense Block (RRDB)is introduced to effectively recover high-quality images from fast scans with fine-details and less noise. Our approach is robust with misalignment introduced from patient's metabolism, and shows valid count-level consistency. Learned Perceptual Image Patch Similarity (LPIPS) and Fréchet Inception Distance (FID) are employed in evaluating the similarity to the standard bone images. To further prove our method practical in clinical settings, image quality of the anonymous images was evaluated by two experienced nuclear physicians on a 5-point Likert scale (5= excellent). The proposed method reaches the state-of-the-art performance on FID and LPIPS with 0.583 and 0.176 for 2× fast scans and 0.583 and 0.185 for 3× fast scans. Clinic evaluation further demonstrated the restored images had a significant improvement compared to fast scan in image quality, technetium 99m-methyl diphosphonate (Tc-99m MDP) distribution, artifacts, and diagnostic confidence. Our method was validated for accelerating whole-body bone scans by introducing real clinical data. Confirmed by nuclear medicine physicians, the proposed method can effectively enhance image diagnostic value, demonstrating potential for efficient high-quality fast bone imaging in practical settings.

Ectopic Intrathoracic Kidney due to Diaphragmatic Eventration Detected on Bone Scan.

The technetium-99m methylene diphosphonate (99mTc-MDP) whole-body bone scan along with single-photon emission computed tomography (SPECT/CT) can detect challenging soft tissue uptake patterns. We present a case of a 67-year-old female in whom the 99mTc-MDP scan, performed 3hours after injection, revealed abnormal soft tissue uptake in the right thoracic region. No functioning right kidney was seen in the right lumbar region. Hybrid SPECT/CT revealed an ectopic right kidney in the subdiaphragmatic location, accompanied by gut loops and eventration of the right-sided diaphragm. This case underscores the value of SPECT/CT in identifying and characterizing unexpected anatomical abnormalities, such as ectopic kidneys.

Imaging signs and the qualitative diagnosis of solitary rib lesions using 99mtechnetium-methylene diphosphonate whole-body bone imaging in patients with a malignant tumor.

The aim of this study was to summarize the valuable information for qualitative diagnosis by investigating the imaging signs from the whole-body bone imaging of solitary rib lesions. A retrospective analysis was conducted of the data from 313 patients with malignant tumors and solitary rib lesions identified using whole-body bone imaging in Department of Nuclear Medicine of Central South University Xiangya School Affiliated Haikou Hospital between January 2015 and December 2017. Based on the final comprehensive diagnosis of the rib lesions, the patients were divided into a bone metastasis group, fracture group, other benign lesions group, and an uncertain group, and the characteristic imaging changes in rib lesions in each group were explored. (I) Significant differences were identified among the 4 groups (P<0.001) in the distribution of lesions in the anterior, posterior, and lateral ribs and proximal costal cartilage. The fracture group had the highest proportion of lesions in the anterior ribs (99/121, 81.8%) and proximal costal cartilage (74.4%, 90/121). (II) Significant differences were detected in morphology, concentration, boundaries, and radioactivity distribution among the 4 groups of patients (P<0.001). The bone metastasis group had the highest proportion of lesions appearing as stripes (35/67, 52.2%), and the fracture group had the highest proportion of lesions appearing as spots (94.2%, 114/121) and the lowest proportion appearing as stripes (3/121, 2.5%). (III) Significant differences were found in the longitudinal diameter, transverse diameter, aspect ratio, and tumor-to-normal tissue ratio between the 4 groups (P<0.001). The longitudinal diameter (27.8±16.0 mm) and aspect ratio (1.9±1.0) of the bone metastasis group were the highest, whereas the longitudinal diameter (15.2±3.9 mm) and aspect ratio (1.0±0.2) of the fracture group were the smallest. This study revealed that different types of solitary rib lesions had relatively characteristic imaging signs in whole-body bone imaging.

Platelet-Rich Fibrin-Enhanced Bone Healing Co-grafted With Either Hydroxyapatite and Beta Tricalcium Phosphate or Demineralized Freeze-Dried Bone in Small Maxillofacial Osseous Defects: A Clinical Comparison.

This study was conducted to clinically compare a commercially available combination of 70:30 nanocrystalline hydroxyapatite (HA) and beta tricalcium phosphate (βTCP) along with platelet-rich fibrin (PRF) with demineralized freeze-dried bone (DFDB) grafts along with PRF in small maxillofacial osseous defects. Thirty patients with one osseous defectwere randomly distributed into two groups of 15 each: Group A and Group B. Group A patients received HA+βTCP+PRF while Group B received DFDB + PRF. Postoperative pain, swelling, wound dehiscence, and the presence or absence of infection were evaluated at various intervals up to seven postop days and compared between the two groups and within either group. A technetium 99m methylene diphosphonate (MDP 99mTc) scan was also done for a representative patient of either group at the end of three months to evaluate the fate of the graft. We found no significant difference between the two groups for any of our parameters. Significant improvements were noted for pain and swelling within either group at various intervals. The MDP 99mTc scan showed increased tracer uptake for the representing patient of either group. HA+βTCPis more inexpensive than DFDB and more readily availableand has no host incompatibility or infection potential, resulting in similar clinical postoperative states as DFDB when either is used with PRF.

Diagnostic value of whole -body diffusion weighted imaging added to bone scan in early diagnosis of bone metastases in breast cancer patients

BackgroundMetastases to the bones are a frequent location of metastasis in advanced breast cancer and are responsible for substantial morbidity and healthcare expenses. Imaging has been crucial in directing patient therapy for decades, contributing to the staging and response evaluation of the skeleton. This research aimed to assess the diagnostic value of whole-body magnetic resonance imaging with diffusion-weighted imaging added to radionuclide bone scans for early diagnosis of bone metastases in breast cancer patients.ResultsThe study was a prospective observational cohort study performed on 20 patients with breast cancer and suspected bone metastases. The patients were evaluated first by obtaining a detailed personal history. Laboratory tests, including CBC, liver, and kidney function tests were assessed. All patients were examined by diffusion-weighted whole-body MRI (DWIBS; diffusion-weighted imaging with background body signal suppression) images and bone scintigraphy after intravenous injection of 20 mci of technetium-99m (99mTc) methylene diphosphonate using a dual head gamma camera. The total number of lesions detected by bone scan was 74, and 75 lesions were seen by DWIBS. Twenty-four lesions were missed by bone scan and detected by DWIBS. Fourteen lesions were detected by bone scan and found free by DWIBS examination in the spine and pelvic bones.ConclusionsWhole body DWIBS seems to be a promising method of imaging in detecting bone metastases from breast cancer that could be used complementary to the traditional bone scan for more accurate diagnosis and staging of the tumor, helping to determine the most appropriate protocol of management.

Skeletal scintigraphy as an important complement for detecting bone metastasis from nasopharyngeal carcinoma

Bone metastasis occurs frequently in patients with nasopharyngeal carcinoma (NPC). Although fluorine-18 fluorodeoxyglucose positron emission tomography with computed tomography (PET/CT) has been proven to be more sensitive at detecting bone metastases than Technetium-99m methylene diphosphonate skeletal scintigraphy in pretreatment patients with NPC in most clinical settings, there have been metastatic lesions that were positive on skeletal scintigraphy but negative on PET/CT scans. Herein, we report the case of a patient with stage IV NPC that manifested as multiple metabolically abnormal lesions on pretreatment skeletal scintigraphy and were considered malignant although they were negative on PET/CT examination. Follow-up evaluations with both skeletal scintigraphy and PET/CT scans as post-therapeutic imaging are also presented.

Segmented linear correlations between bone scan index and prostate cancer biomarkers, alkaline phosphatase, and prostate specific antigen in patients with a Gleason score ≥7.

Technetium-99m methyl diphosphonate bone scintigraphy is relatively easily accessible for detecting bone metastases in prostate cancer patients. However, it is subjective and can be challenging to compare images taken at different time points. The bone scan index (BSI) is a more objective evaluation and allows for better comparison of images. Its correlation with other biomarkers of prostate cancer metastases such as prostate specific antigen (PSA) and alkaline phosphatase (ALP) is not clearly understood. This study thus aimed to compare the BSI correlation to PSA against that of BSI to ALP levels in patients with a Gleason score ≥7.A retrospective analysis of the medical records of 50 prostate cancer patients with a Gleason score of ≥7 referred for a bone scan between January 1, 2015 and December 31, 2018 was undertaken. Bone scans were interpreted visually, and using a semi-automated computer programme to quantify the BSI and its relation to PSA and ALP measurements.For the metastasis positive measurements, there was a statistically significant moderate positive overall linear correlation between BSI and PSA. For ALP and BSI, there were 2 segmented strong positive linear relationships between them. The first segment consisted of ALP < 375 IU/L and BSI >10%, where ALP and BSI were strongly and positively correlated. The other segment tended to have generally low BSI measurements (<10%) and also had a strong and positive correlation.The BSI was found to be better linearly correlated with ALP than PSA.

Bone scan with technetium 99m-methyl diphosphonate, the missing link in the initial staging of muscle-invasive bladder carcinoma.

Accurate staging is crucial to determine the type of treatment for patients with bladder cancer (BCa), especially in high-risk cases. We aimed to assess the role of bone scan in the initial staging of muscle-invasive bladder carcinoma (MIBC). Forty-five patients with MIBC were referred to our tertiary clinic to perform a technetium 99m-methyl diphosphonate (Tc99m-MDP) bone scan from January 2019 to March 2020. The patients underwent bone scintigraphy with pelvic SPECT/CT before radical cystectomy. Whole-body scanning was performed 4 hours after Tc99m-MDP injection in both anterior and posterior views. Since the most common bone involvement site in these patients is the pelvic bones and the spine, pelvic SPECT/CT was performed in all patients. Frequency of skeletal metastasis was 26.7%. Only 19% of the metastases were detected by previous pelvic CT/MRI images performed for routine staging. All the reported skeletal metastases by previous anatomical imaging methods were detected in the bone scan. There was no statistically significant correlation between bone metastasis and the patient's age, lymph nodes metastasis (LNM), hydronephrosis, and muscle-invasive type. The mean serum calcium level was 8.7 ± 0.57 in patients with bone metastasis and 8.87 ± 0.99 in patients without bone metastasis, which was not statistically significant. Bone scan has higher diagnostic performance than conventional imaging methods for detecting bone metastases. It changed the management plan in 8.8% of our patients, so we conclude that performing a whole-body bone scan in the initial staging of MIBC would be helpful.

Quantitative 99mTc-MDP SPECT/CT as an alternative to 18F-NaF PET/CT for objective assessment of osteoblastic bone metastases.

To investigate the correlation between the standardized uptake value (SUV) metrics derived from technetium-99m (99mTc) methylene diphosphonate (MDP) single photon emission computed tomography/computed tomography (SPECT/CT) and fluorine-18 (18F) sodium fluoride (NaF) positron emission tomography (PET)/CT. A total of 129 metastatic lesions from 14 patients who underwent both 99mTc-MDP SPECT/CT and 18F-NaF PET/CT within one month were included in the analyses. The lesions with markedly increased uptake were semi-automatically segmented into a volume of interest in both SPECT and PET images by taking the 42% of maximum uptake as a threshold. Maximum, average and minimum SUV (namely, SUVmax, SUVmean and SUVmin) were recorded for each lesion. The strength of correlation was evaluated with Pearson's correlation analysis. The correlation coefficitients for SUVmax, SUVmean and SUVmin derived SPECT and PET images were 0.652, 0.653 and 0.635, respectively (all P<0.001). Lesions with a volume of at least 5cm3 demonstrated a stronger correlation, increasing the correlation coefficients to 0.714, 0.724 and 0.686, respectively (all P<0.001). The strongest correlation was seen in the lesions of the appendicular skeleton, with coefficients for SUVmax, SUVmean and SUVmin being 0.769, 0.791 and 0.761, respectively (all P<0.001). The SUV metrics derived from 99mTc-MDP SPECT/CT strongly correlate with 18F-NaF PET, especially for relatively large lesions located in the appendicular skeleton. Technetium-99m-MDP SPECT/CT could potentially be used as an alternative method to 18F-NaF PET/CT for quantitative evaluation and objective follow-up of bone metastases.

A rare case of bilateral retinoblastoma metastasizing into the forearm

<br>We present a case of an 8-year-old boy who had undergone chemotherapy with transpupillary thermotherapy for bilateral retinoblastoma (RB) at the age of 6 months. The patient had left forearm pain at the present visit. Bilateral ocular examination did not reveal any signs of RB reactivation. However, bone scan with technetium 99m-methyl diphosphonate (99mTc–MDP) and magnetic resonance imaging (MRI) showed the presence of metastasis in the proximal end of the ulnar bone, which was confirmed on bone marrow biopsy. Based on PCR study and molecular analysis, Ewing's sarcoma was ruled out and the patient was confirmed to have metastatic RB. Subsequently, he underwent chemotherapy along with wide excision of left proximal ulna + extracorporeal radiation therapy (ECRT) + plate reconstruction. At 15-month follow-up, the patient was stable with absence of recurrence of RB. This case highlights the need for long-term follow-up of patients with RB and the need for timely detection and management of metastasis.<br>

Functional Characterization of Posttraumatic Heterotopic Ossification of Tibiofibular Syndesmosis with Dynamic Bone Scan and Single-Photon Emission Computed Tomography/Computed Tomography.

A 53-year-old man was investigated for ongoing right ankle pain and lateral malleolus swelling following a traumatic inversion injury 12 weeks prior. The initial ankle radiograph was normal with no evidence of fracturing. The follow-up radiograph showed bridging ossification in the distal tibiofibular syndesmosis. As the pain did not subside, posttraumatic heterotopic ossification (HO) was suspected, and triple-phase dynamic bone imaging with technetium 99m-methylene diphosphonate was performed to guide further management. The bone scan revealed intense focal tracer activity centered on the HO of the tibiofibular syndesmosis, with no evidence of occult fracturing confirming HO as a pain generator.

Technetium-99m methylene diphosphonate bone scan in evaluation of insufficiency fractures - A pictorial assay and experience from South India.

ABSTRACTInsufficiency fractures (IFs) can be challenging to diagnose due to varied presentations, and sometimes, it changes the course of treatment, as in cancer patients in whom it has to be differentiated with metastatic disease. We present the role of Technetium 99m methylene diphosphonate (99mTc-MDP) bone scan, which is a low-cost, simple to perform, whole body diagnostic investigation in the diagnosis of IFs. This is a retrospective analysis of all patients who underwent a 99mTc-MDP bone scan in a tertiary care teaching hospital during 2013–2017 and were diagnosed as having an IF on bone scan. The bone scans were performed on a dual-head gamma camera using low-energy high-resolution collimators. Of all the bone scan performed during 2013–2017, a total of 138 patients with a mean age of 57.5 ± 14.7 years were diagnosed as having IFs based on bone scan and final clinical diagnosis. Among them, the most common complaint was regional bony pain in 62% of patients, while the most common cause was osteoporosis in 47% of patients, both postmenopausal and senile osteoporosis. In all, 265 sites of fractures were identified with a fracture average of 1.9/patient, the most common site being dorsolumbar vertebrae, followed by ribs and lower limb bones. Many unusual sites were also identified such as talus, sternum, clavicle, and scapula. 99mTc-MDP bone scan, being noninvasive whole-body imaging, is a useful investigation for evaluation of IFs and in correlation with biochemical analysis and other imaging can be used to determine the etiology of IF.

Role of MDP SPECT/CT Bone Scintigraphy in Evaluation of Patients with Malignant Otitis Externa Compared to HRCT: A prospective Study.

Background: Malignant otitis externa (MOE) is a potentially fatal disease; accurate assessment of the extent of this disease is warranted to plan the course of treatment and to predict the prognosis. The aim of the study was to compare the efficiency of high resolution computed tomography (HRCT) with that of 99mTechnetium methylene diphosphonate (99mTc-MDP) single photon emission computed tomography/computed tomography (SPECT/CT) in precise evaluation of the disease extent and to evaluate the prognostic value of SPECT/CT staging in terms of therapeutic response and survival in patients with MOE. Patients and Methods: This prospective study included twenty-five patients (17 males and 8 females) with clinically diagnosed MOE, all of themunderwent both HRCT and 99mTc-MDP SPECT/CT imaging of the skull. Based on 99mTc-MDP uptake in SPECT/CT scan, the findings were staged accordingly and compared with the findings of HRCT in all patients. In addition, clinical outcome and disease-free survival (DFS) were analyzed according to the SPECT/CT staging.Results: Out of 25 patients included in our study, HRCT showed osseous changes in only 4/25 (16%) patients, 99mTc-MDP SPECT/CT demonstrated more osseous involvement in 21/25 (84%) patients. No patients in stage I in this work, 8 patients had disease confined to the mastoid/temporal bone, not reaching midline (stage II), 6 of them were surviving with recovery and clinical improvement, and 2 patients died. Three patients had petrous involvement reaching midline (stage III), 2 of them were surviving with clinical improvement, and the 3rd patient died. Fourteen patients had sphenoid involvement/disease extended to the contralateral temporal bone (stage IV), 5 of them were surviving with recovery and clinical improvement, 5 were surviving, yet had disease progression, and 4 patients died within less than one year of diagnosis. At the end of follow up period; in total; 7 patients had died,of whom 3 in stage IV died due to MOE, while the remaining 4 cases (2 in stage II, 1 in stage III, and 1 in stage IV) died due to unrelated causes. Both of disease duration and SPECT/CT staging were statistically significant predictor factors for DFS (P=0.05 and 0.047 respectively).Conclusion: SPECT/CT has a higher sensitivity than HRCT in determining the exact extent of MOE and was much better correlated with disease prognosis.

Polyarthralgia and Myalgia Syndrome after ChAdOx1 nCOV-19 Vaccination.

Since February 26, 2021, when vaccination against coronavirus disease 2019 (COVID-19) began in South Korea, patients who visited the Korea University Guro Hospital with suspected adverse events after COVID-19 vaccination were monitored actively with interest. We encountered five unusual cases of polyarthralgia and myalgia syndrome in patients who received the ChAdOx1 nCOV-19 (AstraZeneca) vaccine. The patients (median age 67 years) were not previously diagnosed with arthropathy and rheumatologic diseases. They developed fever, myalgia, joint pain, and swelling three to seven days after vaccination. The symptoms persisted for up to 47 days despite antipyretic treatment. Arthralgia occurred in multiple joints, including small and large joints. A whole-body Technetium-99m methylene diphosphonate bone scan revealed unusual uptakes in the affected joints. Non-steroidal anti-inflammatory drugs with or without prednisolone relieved the symptoms of all patients. Further monitoring is required to clarify the long-term prognosis of this syndrome.

99mTc-polyphosphonate labelling – Enhancement of a novel method for the quantification of osteogenic differentiation of MSCs in vitro

Bone tissue engineering is a fast-growing field in regenerative medicine. Consequently, there is a high demand for new, fast and reliable methods to track and quantify the osteogenic differentiation of cells. Recently, a novel method was published to non-destructively quantify the hydroxyapatite content of monolayer and 3-dimensional mesenchymal stem cell cultures using the ability of 99mTechnetium-methylene diphosphonate (MDP), a well-established tracer in clinical nuclear medicine, to bind to newly synthesized hydroxyapatite. In the present study, two other commonly used 99mTechnetium tracers, 2,3-dicarboxypropane-1,1-diphosphonate (DPD) and hydroxydiphosphonate (HDP), were evaluated to see if they could also be used for the same purpose. Furthermore, we investigated if labelling at various timepoints influenced the effectiveness of the labelling. The results were analysed using one-factor ANOVA followed by Bonferroni post-hoc testing. This revealed a highly significant difference between the three osteogenic groups at each timepoint compared to their corresponding negative controls. However, there was no statistically significant difference between the three different tracers (MDP, DPD, HDP) in the osteogenic groups. Therefore all three tracers are of similar value when quantifying the extracellular hydroxylapatite content in osteogenic stem cells cultures.

Skeletal Disease Acquisition in Fibrous Dysplasia: Natural History and Indicators of Lesion Progression in Children.

Fibrous dysplasia (FD) is a rare mosaic disorder resulting in fractures, pain, and disability. Bone lesions appear during childhood and expand during skeletal growth. The rate at which FD lesions progress and the biochemical determinants of FD lesion formation have not been established, making it difficult to investigate and implement preventative therapies. The purpose of this study was to characterize FD lesion progression in children, and to identify clinical variables associated with progressive disease. Clinical data and imaging from an ongoing natural history study at the National Institutes of Health (NIH) were reviewed. 99m-Technetium methylene diphosphonate (99Tc-MDP) scans were used to determine Skeletal Burden Score (SBS), a validated quantitative scoring system. FD progression rate was determined by the change in the SBS in each patient per year. Thirty-one children had serial 99Tc-MDP scans, with a median age at first scan of 6 years (interquartile range [IQR] 4-8, range 2-10), and median follow-up 1.1 years (IQR 1.1-2.1, range 0.7-11.2). The median FD progression rate for the total group was 2.12 SBS units/year (IQR 0.81-2.94, range 0.05-7.81). FD progression rates were highest in children under age 8 years and declined with age (p=0.03). Baseline disease severity was associated with subsequent disease progression (p=0.009), with the highest FD progression rates in patients with moderate disease (baseline SBS 16-30), and lowest progression rates in those with severe disease (SBS ≥50). Serum levels of the bone formation marker osteocalcin were positively correlated with subsequent FD progression rate (p=0.01, R=0.58). There was no association between FD progression and baseline endocrinopathies, fractures, or surgery rates. FD lesions progress during childhood, particularly in younger children and those with moderate involvement. Osteocalcin may potentially serve as a biomarker for progressive disease. These findings may allow clinicians to investigate preventative therapies, and to identify children with FD who are candidates for early interventions. Published 2022. This article is a U.S. Government work and is in the public domain in the USA.

Early-Phase SPECT/CT for Diagnosing Osteomyelitis: A Retrospective Pilot Study.

ObjectiveThe aim of this pilot study was to investigate the potential of early-phase single-photon emission computed tomography (SPECT)/computed tomography (CT) using technetium-99m methyl diphosphonate (99mTc-MDP) for diagnosing osteomyelitis (OM).Materials and MethodsTwenty-one patients with suspected OM were enrolled retrospectively. Three-phase bone scan (TPBS), early-phase SPECT/CT (immediately after blood pool planar imaging), and delayed-phase SPECT/CT (immediately after delayed planar imaging) were performed. The final diagnoses were established through surgery or clinical follow-up for over 6 months. We compared three diagnostic criteria based on (I) TPBS alone, (II) combined TPBS and delayed-phase SPECT/CT, and (III) early-phase SPECT/CT alone.ResultsOM was diagnosed in 11 of 21 patients (nine surgically and two clinically). Of the 11 OM patients, criterion-I, criterion-II, and criterion-III were positive in six, seven, and 10 patients, respectively. Of the 10 non-OM patients, criterion-I, criterion-II, and criterion-III were negative in five, five, and seven patients, respectively. The sensitivity/specificity/accuracy of criterion-I, criterion-II, and criterion-III for diagnosing OM were 54.5%/50.0%/55.0%, 63.6%/50.0%/57.1%, and 90.9%/70.0%/87.5%, respectively.ConclusionThis pilot study demonstrated the potential of using the early-phase SPECT/CT to diagnose OM. Based on the results, prospective studies with a larger sample size should be conducted to confirm the efficacy of early-phase SPECT/CT.

Utility of Single-Photon Emission Computed Tomography/Computed Tomography in Suspected Unilateral Condylar Hyperplasia: A Histopathologic Validation Study

The purpose of this study is to evaluate the utility of hybrid single-photon emission computed tomography (SPECT) and computed tomography (CT) with technetium-99m methylene diphosphonate in patients with suspected active unilateral condylar hyperplasia (UCH) using histopathology as the reference standard. Twenty-four patients with suspected active UCH prospectively underwent technetium-99m methylene diphosphonate planar bone scintigraphy with SPECT/CT of the mandible. Qualitative and quantitative readings for growth activity were performed by 3 nuclear medicine physicians and the final diagnosis was derived from postoperative histopathological examination. Readings were reported as positive, equivocal, or negative. Total, maximum, and mean counts were recorded for each condyle on SPECT/CT images. The uptake of the index (suspected) condyle was expressed as a count ratio (Rtotal, Rmean, Rmax), a percentage uptake (Ptotal, Pmean, Pmax), background-corrected counts (Btotal, Bmean, Bmax), as well as CT-based condylar diameters (RCT,PCT) relative to the contralateral condyle. Interobserver agreement was 0.79 and 0.83 for planar bone scintigraphy and SPECT/CT, respectively, with a total of 5 and 1 equivocal readings from the respective modalities. Surgery was performed in 22 patients; all of them had pathologically proven UCH. SPECT/CT was slightly more sensitive than planar bone scintigraphy (91 vs 78%) with identical specificity (96%). Rtotal, Rmean, Ptotal, and Pmean demonstrated area under the curve between 84% and 86%. Metrics based on CT diameters and background-corrected counts were not associated with UCH diagnosis. Quantitative approaches based on total or mean count ratio or relative count percentage were equally predictive for UCH diagnosis; however, they were slightly less sensitive compared with qualitative technetium-99m methylene diphosphonate SPECT/CT evaluation. SPECT/CT evaluation has the potential to decrease the equivocal readings.

Value of Mastoidectomy in Malignant Otitis External

Objectives: To define the value of mastoidectomy in cases of malignant otitis externa.Study design: Case Series.Patients and Methods: Study of Patients with malignant otitis externa (MOE) treated by mastoidectomy from Jan 2016 to October 2018 and followed up clinically, laboratory and radiologically.Results: Postsurgical siginifacant resolution of symptoms and regression of the disease. Otalgia showed siginificant decrease by assessment with Visual Analogue Score. Also there are improvement of otorrhea, decrease of the reactive indicators as Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) and radiological improvement of osteomyelitis in Computed Tomography and technetium-99m methylene diphosphonate (MDP) and gallium-67 citrate scintigraphy.Conclusion: In patients with MOE, resistant to medical treatment and have evidence of mastoiditis and Middle ear affection, cortical mastoidectomy may be the treatment for both symptom relieve and regression of the disease

Improving technetium-99m methylene diphosphonate bone scan images using histogram specification technique.

In this study, we have proposed and validated that histogram of a good-quality bone scan image can enhance a poor-quality bone scan image. The histograms of two good-quality technetium-99m methyl diphosphonate bone scan images IA and IB recommended by nuclear medicine physicians (NMPs) were used to enhance 87 poor-quality bone scan images. Processed images and their corresponding input images were compared visually by two NMPs with scoring and also quantitatively using entropy, Structural similarity index measure, edge-based contrast measure, and absolute brightness mean error. Barnard's unconditional test was applied with a null hypothesis that the histogram of both IA and IB produces similar output image at α =0.05. The mean values of quantitative metrices of the processed images obtained using IA and IB were compared using Kolmogorov–Smirnov test. Histogram of a good-quality bone scan image can enhance a poor-quality bone scan image. Visually, histogram of IB improved statistically significantly higher proportion (P < 0.0001) of images (86/87) as compared to histogram of IA (51/87). Quantitatively, IB performed better than IA, and the Chi-square distance of input and IB was smaller than that of IA. In addition, a statistically significant (P < 0.05) difference in all the quantitative metrics among the outputs obtained using IA and IB was observed. In our study, reference histogram of good-quality bone scan images transformed the majority of poor-quality bone scan images (98.85%) into visually good-quality images acceptable by NMPs.