Single-photon emission computed tomography/computed tomography arthrography of wrist, ankle, and knee joints:

Diagnosis of Cardiac Rehabilitation after Percutaneous Coronary Intervention in Acute Myocardial Infarction Patients by Emission Computed Tomography Image Features under Filtered Back Projection Reconstruction Algorithm

This study aimed to explore the application value of emission computed tomography (ECT) imaging technology based on filtered back projection reconstruction algorithm (FBP) in cardiac function examination after percutaneous coronary intervention (PCI) in patients with acute myocardial infarction (AMI). Eighty patients with myocardial infarction diagnosed by medical history, electrocardiograph (ECG), and myocardial enzyme admitted to hospital from February 2018 to February 2019 were selected as the research objects. All patients underwent PCI seven days after the onset of myocardial infarction. ECT was performed for all patients before and after surgery. In addition, all ECT images were processed by the FBP reconstruction algorithm. On this basis, preoperative and postoperative cardiac surgery function and ischemia of the patients were diagnosed. Then, the diagnostic results were compared with the results of coronary angiography and echocardiogram. The results showed that all patients had a total of 541 segments before PCI surgery. ECT examination revealed 294 abnormal segments of the ventricular wall, with a total score of 585 points. A total of 100 segments were scored with 1 point, a total of 194 segments were scored with 2 points, and a total of 50 segments were scored with 3 points. After PCI, the number of abnormal segments was reduced to 58, with a total score of 193. There were 6 segments with a score of 1, 44 segments with a score of 2, and 5 segments with a score of 3. The left ventricular diastolic volume (EDV), left ventricular systolic volume (ESV), stroke volume (CO), and ejection fraction (EF) of the patients before the operation were 148 ± 16 mL, 77 ± 14.5 mL, 4.29 ± 0.37 L/min, and 41.9 ± 8%, respectively. The EDV, ESV, CO, and EF of the patients after surgery were 132 ± 16 mL, 62 ± 13 mL, 4.89 ± 0.71, and 53 ± 6%, respectively. Significant changes occurred in various systolic function parameters before and after surgery, P < 0.05. The standardized regression coefficients of the three groups were 0.32, 0.41, and 0.47, respectively, P < 0.05, which indicated that the greater the coronary artery stenosis rate, the higher the diagnostic coincidence rate of left anterior descending limb (LAD), left circumflex branch (LCX), and left coronary artery (RCA). The conformity of ECT imaging in the LCX group for diagnosis of myocardial ischemia was higher than that of UCG, P < 0.05. To sum up, the ECT technology based on the FBP reconstruction algorithm had a good application prospect in the diagnosis of cardiac function recovery in AMI patients after PCI.

Bone SPECT/CT in the Evaluation of Painful Total Ankle Replacement: Validation of Localization Scheme and Preliminary Evaluation of Diagnostic Patterns

PURPOSE

Third-generation total ankle replacement (TAR) is an increasingly popular and effective treatment for end-stage osteoarthritis, yet identifying causes of failure remains challenging. We evaluated integrated bone SPECT/CT in recurrent pain after TAR by validating a standardized reporting scheme, identifying uptake patterns, and assessing diagnostic performance and impact on clinical management.

PATIENTS AND METHODS

A total of 24 TARs in 16 patients with persistent or recurrent pain received integrated bone SPECT/CT using diagnostic CT settings. Images were retrospectively reviewed, and a novel localization scheme was validated by assessing interrater agreement. Distinct uptake patterns were identified, and diagnostic test characteristics were estimated. Reference standard consisted of clinical follow-up, laboratory findings, and subsequent procedures, including revision surgery.

RESULTS

Standardized scoring of bone SPECT/CT uptake was highly reproducible (intraclass correlation coefficient, 0.79; 95% confidence interval [CI], 0.75-0.82). The final diagnoses were gutter impingement (n = 12), periprosthetic (stress) fracture (n = 5), loosening (n = 5), tarsal arthritis (n = 1), and erysipelas (n = 1). Overall, the diagnostic test characteristics of bone SPECT/CT were as follows: sensitivity of 100% (95% CI, 82%-100%), specificity of 80% (95% CI, 28%-99%), and accuracy of 96% (95% CI, 79%-100%). Gutter impingement, periprosthetic fracture, and loosening were correctly identified in all cases revealing distinct uptake patterns. Importantly, persistent diffuse uptake was frequently observed, warranting cautious interpretation. Bone SPECT/CT impacted clinical management in 86%, with symptomatic improvement in 83% of patients.

CONCLUSIONS

Integrated bone SPECT/CT of painful TARs may benefit from standardized localization to reveal distinct uptake patterns representing common complications after TAR. Initial results show highly promising diagnostic value with potentially important impact on clinical management.

Computed Tomography (CT) Protocols Associated with Cardiac and Bone Single-Photon Emission Computed Tomography/CT (SPECT/CT) in Korea

PURPOSE

Single-photon emission computed tomography/computed tomography (SPECT/CT) is an advanced hybrid nuclear medicine technology that generates both functional and anatomical images in a single study. As utilization of SPECT/CT in Korea has been increasing, the purpose of this study was to survey its application of cardiac and skeletal SPECT/CT imaging for protocol optimization.

METHODS

We surveyed CT protocols established for cardiac and skeletal SPECT/CT. We searched the guidelines for the CT protocols for SPECT/CT and reviewed the literature recently published.

RESULTS

Among 36 hybrid SPECT scanners equipped with four or more multi-channel detector CTs (MDCTs), 18 scanners were used to perform cardiac studies at both very low current CT (30-80 mA; 11.1%) and ultra-low current CT (13-30 mA; 88.9%). Among the 33 canners, very low current (≤ 80 mA) CT or low current CT (80-130 mA) was used in 23.5%, and 41.8% for spine disorders, and in 36.4% or 30.3% for foot/ankle disorders, respectively. In the CT reconstructions, slice thickness of 5 mm for cardiac studies was most commonly used (94.4%); thinner slices (0.6-1.0 mm) for spine and foot/ankle studies were used in 24.2% and 45.5%, respectively. We also reviewed the international guidelines.

CONCLUSIONS

The results and current recommendations will be helpful for optimizing CT protocols for SPECT/CT. Optimization of SPECT/CT protocols will be required for generating the proper strategy for the specific lesions and clinical purpose.