SPECT/CT bone scintigraphy to evaluate low back pain in young athletes: common and uncommon etiologies

Bone scintigraphy with SPECT/CT in paediatric patients with neck and back pain in comparison with other imaging modalities: the experience of a tertiary paediatric referral centre

OBJECTIVE

Retrospective review of the additional clinical value provided by single photon emission computed tomography-computed tomography (SPECT/CT) in children and adolescents with back pain.

METHODS

A total of 207 consecutive paediatric patients (94 males, 113 females, age range 5-17 years, median age 14 years) were reviewed after referral to the spinal surgery clinic of a paediatric teaching hospital between November 2009 and February 2021. All patients had either only whole spine X-rays or whole spine x-rays and MRI, along with bone scan with planar whole-body images and SPECT/CT (with spot views of painful area).

RESULTS

X-ray identified the pain generator in 23 of 177 (13.0%) cases. MRI identified the pain generator in 49 of 165 (29.7%) cases. SPECT/CT reported relevant positive findings which identified the pain generator in 107 of 185 (57.8%) cases. SPECT/CT changed patients' management in 72 of 185 (38.9%) cases. SPECT/CT was most effective at identifying the pain generator in cases of facet arthropathy, previous vertebral fracture and patients with previous deformity correction, where the pain generator was identified in 76.5% (13 of 17), 71.4% (5 of 7) and 63.4% (26 of 41) of cases, respectively. CT settings were adjusted to minimise the radiation burden (50 mAs/80kVp under 8 years, 24 mAs/110 kVp over 8 years).

CONCLUSION

The role of SPECT/CT in diagnosing back pain is justified in selected paediatric patients, particularly with diagnostic uncertainty using conventional imaging. The CT component of the SPECT/CT study produced a lower radiation dose than conventional CT imaging, whilst producing bone images of diagnostic quality.

Update on Pediatric Nuclear Medicine in Acute Care

Various radiopharmaceuticals are available for imaging pediatric patients in the acute care setting. This article focuses on the common applications used on a pediatric patient in acute care. To confirm the clinical diagnosis of brain death, brain scintigraphy is considered accurate and has been favorably compared with other methods of detecting the presence or absence of cerebral blood flow. Ventilation-perfusion lung scans are easy and safe to perform with less radiation exposure than computed tomography pulmonary angiography and remain an appropriate procedure to perform on children with suspected pulmonary embolism as a first imaging test in a hemodynamically stable patient with no history of lung disease and normal chest radiograph. 99mTc-pertechnetate scintigraphy (Meckel's scan) is the best noninvasive procedure to establish the diagnosis of ectopic gastric mucosa in Meckel's diverticulum. 99mTcred blood cell scintigraphy generally is useful for assessing lower GI bleeding in patients from any cause. Hepatobiliary scintigraphy is the most accurate diagnostic imaging modality for acute cholecystitis. 99mTc-dimercaptosuccinic acid scintigraphy is the simplest, and the most reliable and sensitive method for the early diagnosis of focal or diffuse functional cortical damage. 99mTcmercaptoacetyltriglycine scintigraphy is used to evaluate for early and late complications of renal transplantation. Bone scintigraphy is a sensitive and noninvasive technique for diagnosis of bone disorders such as osteomyelitis and fracture. 18F-fluorodeoxyglucose-positron emission tomography could be valuable in the evaluation of fever of unknown origin in pediatric patients, with better sensitivity and significantly less radiation exposure than a gallium scan. Moving forward, further refinement of pediatric radiopharmaceutical administered activities, including dose reduction, greater radiopharmaceutical applications, and updated consensus guidelines is warranted, with the use of radionuclide imaging likely to increase.

Visual Scoring of Sacroiliac Joint/Sacrum Ratios of Single-Photon Emission Computed Tomography/Computed Tomography Images Affords High Sensitivity and Negative Predictive Value in Axial Spondyloarthritis

Spondyloarthritis (SpA) is characterized by inflammatory back pain. Magnetic resonance imaging (MRI) was the earlier gold standard technique for detecting early inflammatory change. We reassessed the diagnostic utility of sacroiliac joint/sacrum (SIS) ratios of single-photon emission computed tomography/computed tomography (SPECT/CT) for identifying sacroiliitis. We aimed to investigate of SPECT/CT in diagnosing SpA using a rheumatologist's visual scoring of SIS ratios assessment. We conducted a single-center, medical records review study of patients with lower back pain who underwent bone SPECT/CT from August 2016 to April 2020. We employed semiquantitative visual bone scoring methods of SIS ratio. The uptake of each sacroiliac joint was compared to that of the sacrum (0-2). A score of 2 for the sacroiliac joint of either side was considered diagnostic of sacroiliitis. Of the 443 patients assessed, 40 had axial SpA (axSpA), 24 being radiographic axSpA and 16 being nonradiographic axSpA. The sensitivity, specificity, and positive and negative predictive values of SIS ratio of SPECT/CT for axSpA were 87.5%, 56.5%, 16.6%, and 97.8%, respectively. In receiver operating curve analysis, MRI better diagnosed axSpA than did SIS ratio of SPECT/CT. Although the diagnostic utility of SIS ratio of SPECT/CT was inferior to MRI, visual scoring of SPECT/CT affords high sensitivity and negative predictive value in axSpA. When MRI is inappropriate for certain patients, SIS ratio of SPECT/CT is an alternative tool for identifying axSpA in real practice.

ACR Appropriateness Criteria® Low Back Pain: 2021 Update

In the United States, acute low back pain, with or without radiculopathy, is the leading cause of years lived with disability and the third ranking cause of disability-adjusted life-years. Uncomplicated acute low back pain and/or radiculopathy is a benign, self-limited condition that does not warrant any imaging studies. Imaging is considered in those patients who have had up to 6 weeks of medical management and physical therapy that resulted in little or no improvement in their back pain. It is also considered for those patients presenting with red flags, raising suspicion for a serious underlying condition, such as cauda equina syndrome, malignancy, fracture, or infection. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Symptomatic Oppenheimer ossicle: a rare mimic of pars interarticularis fracture

We report a case of symptomatic Oppenheimer ossicle in an 18-year-old male who presented with back pain. L5 pars interarticularis defect was suspected on initial lumbar spine radiographs. A subsequent technetium99m-methylene diphosphonate (Tc99m-MDP) bone scintigraphy with single-photon emission computed tomography/computed tomography (SPECT/CT) revealed focal radiotracer uptake in an Oppenheimer ossicle in L2 vertebra. CT was negative for pars defect. Oppenheimer ossicle is a developmental variant resulting from an unfused accessory ossification center at the tip of the articular process. It is important to recognize this entity as a rare cause of low back pain. Focal tracer uptake can mimic changes from pars interarticularis defect on planar and SPECT images. SPECT/CT helps to resolve both entities. To our knowledge, this is also the first report in English literature describing a symptomatic Oppenheimer ossicle on a bone scan.

Clinical applications of nuclear medicine in the diagnosis and assessment of musculoskeletal sports injuries

Increased participation in sports and physical exercise are widely promoted as an approach to a physically active lifestyle which has a positive effect on healthy aging, in patients and athletes of all ages, beginners and experts, including amateur athletes and professional athletes. Unfortunately, this has caused a higher incidence of sports-related injuries. In the sports context, the early and accurate diagnosis of injuries is of the utmost importance in order to enable early treatment to achieve a full recovery. Imaging techniques are increasingly important for the successful diagnosis and management of the patient. The nuclear medicine techniques with bone tracers provide physiological and metabolic information in the early phases of musculoskeletal injuries, which often precede anatomical changes and they reflect changes in bone turnover. This allows early diagnosis, along with evaluation of the activity and phase of the injury. In this article, the applications of nuclear medicine techniques, focusing on bone scintigraphy, alongside the important contribution of hybrid studies (SPECT/CT), in the diagnosis of bone and soft tissue sports injuries, will be described. In addition, we explain their usefulness in the expression of the pathophysiology of these lesions and their scintigraphic patterns. The article will also describe biomechanical and physiopathological aspects, injury mechanisms and clinical presentations of bone and joint sports injuries, knowledge of this is essential for the correct diagnostic assessment of imaging studies.

Back Injuries

When searching for evidence-based answers about treating athletes with low back injury/pain, there are some difficulties. The first is defining who is an athlete. The second problem is that the lifetime prevalence of low back pain in the general population in our country approaches 100. Last, most studies published only deal with a narrow population of athletes, often performing very different types of physical activity. We searched the literature for studies that specifically evaluated athletes longitudinally. This article reviews the demographics, diagnostic challenges, history and physical examination, imaging choices, treatment, and controversies encountered when treating this population.

Prevalence of Spondylolysis in Symptomatic Adolescent Athletes: An Assessment of Sport Risk in Nonelite Athletes

OBJECTIVE

To assess the risk of spondylolysis by sport in nonelite adolescent athletes with low back pain (LBP).

DESIGN

Retrospective case series.

SETTING

Hospital-based sports medicine clinic.

PATIENTS

The medical charts of 1025 adolescent athletes with LBP (age 15 ± 1.8 years) were examined; 308 (30%) were diagnosed with a spondylolysis.

ASSESSMENT OF RISK

Risk of spondylolysis was assessed in 11 sports for males and 14 sports for females.

MAIN OUTCOME MEASURE

Relative risk of diagnosis of spondylolysis injury.

RESULTS

The risk of spondylolysis differed by sex with baseball (54%), soccer (48%), and hockey (44%) having the highest prevalence in males and gymnastics (34%), marching band (31%), and softball (30%) for female athletes. Baseball was the only sport to demonstrate a significant increased risk of spondylolysis.

CONCLUSIONS

The sports with the greatest risk of spondylolysis in adolescent athletes in this study were not consistent with published literature. Clinicians should be cautious generalizing high-risk sports to their practice, as geographic region and level of the athlete may significantly influence the incidence of spondylolysis in the population they are treating.

Two decades of SPECT/CT - the coming of age of a technology: An updated review of literature evidence

PURPOSE

Single-photon emission computed tomography (SPECT) combined with computed tomography (CT) was introduced as a hybrid SPECT/CT imaging modality two decades ago. The main advantage of SPECT/CT is the increased specificity achieved through a more precise localization and characterization of functional findings. The improved diagnostic accuracy is also associated with greater diagnostic confidence and better inter-specialty communication.

METHODS

This review presents a critical assessment of the relevant literature published so far on the role of SPECT/CT in a variety of clinical conditions. It also includes an update on the established evidence demonstrating both the advantages and limitations of this modality.

CONCLUSIONS

For the majority of applications, SPECT/CT should be a routine imaging technique, fully integrated into the clinical decision-making process, including oncology, endocrinology, orthopaedics, paediatrics, and cardiology. Large-scale prospective studies are lacking, however, on the use of SPECT/CT in certain clinical domains such as neurology and lung disorders. The review also presents data on the complementary role of SPECT/CT with other imaging modalities and a comparative analysis, where available.

Acupuncture and Neural Mechanism in the Management of Low Back Pain-An Update

Within the last 10 years, the percentage of low back pain (LBP) prevalence increased by 18%. The management and high cost of LBP put a tremendous burden on the healthcare system. Many risk factors have been identified, such as lifestyle, trauma, degeneration, postural impairment, and occupational related factors; however, as high as 95% of the cases of LBP are non-specific. Currently, LBP is treated pharmacologically. Approximately 25 to 30% of the patients develop serious side effects, such as drowsiness and drug addiction. Spinal surgery often does not result in a massive improvement of pain relief. Therefore, complementary approaches are being integrated into the rehabilitation programs. These include chiropractic therapy, physiotherapy, massage, exercise, herbal medicine and acupuncture. Acupuncture for LBP is one of the most commonly used non-pharmacological pain-relieving techniques. This is due to its low adverse effects and cost-effectiveness. Currently, many randomized controlled trials and clinical research studies have produced promising results. In this article, the causes and incidence of LBP on global health care are reviewed. The importance of treatment by acupuncture is considered. The efforts to reveal the link between acupuncture points and anatomical features and the neurological mechanisms that lead to acupuncture-induced analgesic effect are reviewed.

Negative magnetic resonance imaging in three cases of anterior tibial cortex stress fractures

Anterior mid-tibial cortex stress fractures (ATCSF) are uncommon and notoriously challenging to treat. They are termed high risk due to their predilection to prolonged recovery, nonunion and complete fracture. Early diagnosis is essential to avoid progression and reduce fracture complications. Imaging plays a key role in confirming the diagnosis. Magnetic resonance imaging (MRI) is accepted as the gold standard modality due to its high accuracy and nonionizing properties. This report describes three cases of ATCSFs in recreational athletes who had positive radiographic findings with no significant MRI changes. Two athletes had multiple striations within their tibias. Despite the radiographic findings, their severity of symptoms were low with mild or no tenderness on examination. Clinicians should be mindful that the ATCSFs may not present with typical acute stress fracture symptoms. We recommend that plain radiographs should be used as the first line investigation when suspecting ATCSFs. Clinicians should be aware that despite MRI being considered the gold standard imaging modality, we report three cases where the MRI was unremarkable, whilst radiographs and computed tomography confirmed the diagnosis. We urge clinicians to continue to use radiographs as the first line imaging modality for ATCSFs and not to directly rely on MRI. Those who opt directly for MRI may be falsely reassured causing a delay in diagnosis.

Paediatric nuclear medicine imaging

BACKGROUND

Nuclear medicine imaging explores tissue viability and function by using radiotracers that are taken up at cellular level with different mechanism. This imaging technique can also be used to assess blood flow and transit through tubular organs. Nuclear medicine imaging has been used in paediatrics for decades and this field is continuously evolving.

SOURCES OF DATA

The data presented comes from clinical experience and some milestone papers on the subject.

AREAS OF AGREEMENT

Nuclear medicine imaging is well-established in paediatric nephro-urology in the context of urinary tract infection, ante-natally diagnosed hydronephrosis and other congenital renal anomalies. Also, in paediatric oncology, I-123-meta-iodobenzyl-guanidine has a key role in the management of children with neuroblastic tumours. Bone scintigraphy is still highly valuable to localize the source of symptoms in children and adolescents with bone pain when other imaging techniques have failed. Thyroid scintigraphy in neonates with congenital hypothyroidism is the most accurate imaging technique to confirm the presence of ectopic functioning thyroid tissue.

AREAS OF CONTROVERSY

Radionuclide transit studies of the gastro-intestinal tract are potentially useful in suspected gastroparesis or small bowel or colonic dysmotility. However, until now a standardized protocol and a validated normal range have not been agreed, and more work is necessary. Research is ongoing on whether magnetic resonance imaging (MRI), with its great advantage of great anatomical detail and no ionizing radiations, can replace nuclear medicine imaging in some clinical context. On the other hand, access to MRI is often difficult in many district general hospitals and general anaesthesia is frequently required, thus adding to the complexity of the examination.

GROWING POINTS

Patients with bone pain and no cause for it demonstrated on MRI can benefit from bone scintigraphy with single photon emission tomography and low-dose computed tomography. This technique can identify areas of mechanical stress at cortical bone level, difficult to demonstrate on MRI, which can act as pain generators. Positron emission tomography (PET) is being tested in the staging, response assessment and at the end of treatment of several paediatric malignancies. PET is becoming more widely utilized in neurology in the pre-surgical assessment of some children with drug resistant epilepsy.

AREAS TIMELY FOR DEVELOPING RESEARCH

The use of PET/MRI scanners is very attractive as it combines benefits of MR imaging with the assessment of cellular viability and metabolism with PET in one examination. This imaging technique will allow important research on tumour in-vivo metabolism (possible applications include lymphomas, neuroblastomas, malignant germ cell tumours andbrain tumours), with the aim of offering a personalized biological profile of the tumour in a particular patient. Ground-breaking research is also envisaged in neurosciences, especially in epilepsy, using PET tracers that would enable a better identification of the epileptogenic focus, and in psychiatry, with the use of radiolabeled neurotransmitters. In paediatric nephro-urology, the identification of the asymptomatic child with ante-natally diagnosed hydronephrosis at risk of losing renal parenchymal function if left untreated is another area of active research involving radionuclide renography.

Bone scintigraphy in patients with pain

Nuclear medicine imaging is widely used in pain medicine. Low back pain is commonly encountered by physicians, with its prevalence from 49% to 70%. Computed tomography (CT) or magnetic resonance imaging (MRI) are usually used to evaluate the cause of low back pain, however, these findings from these scans could also be observed in asymptomatic patients. Bone scintigraphy has an additional value in patients with low back pain. Complex regional pain syndrome (CRPS) is defined as a painful disorder of the extremities, which is characterized by sensory, autonomic, vasomotor, and trophic disturbances. To assist the diagnosis of CRPS, three-phase bone scintigraphy is thought to be superior compared to other modalities, and could be used to rule out CRPS due to its high specificity. Studies regarding the effect of bone scintigraphy in patients with extremity pain have not been widely conducted. Ultrasound, CT and MRI are widely used imaging modalities for evaluating extremity pain. However, SPECT/CT has an additional role in assessing pain in the extremities.