Update on imaging of the discoid meniscus

Discoid menisci represent a range of morphological meniscal variants, most commonly involving the lateral meniscus. Clinical presentation ranges from an asymptomatic incidental finding to snapping, pain, swelling and reduced range of knee movement. Symptomatic presentation of discoid menisci is usually due to meniscal tears and instability resulting from abnormal meniscal morphology and ultrastructure, with absent peri-meniscal ligamentous and meniscocapsular attachments characteristic of the Wrisberg sub-type. This article reviews the current classification systems of discoid menisci, gross morphological characteristics of each sub-type and ultrastructure. Clinical presentation, arthroscopic findings and indirect radiological diagnostic criteria are described, as are the MRI findings of normal and pathological discoid menisci. Current concepts of surgical management and outcomes of the discoid meniscus are also briefly discussed.

MRI signal and morphological alterations of the suprapatellar fat pad in asymptomatic subjects: are these normal variants?

OBJECTIVE

To study the prevalence of suprapatellar fat pad (SPFP) MR alterations in asymptomatic subjects, in relation to a wide range of clinical/imaging parameters, including muscle performance tests and physical activity data.

MATERIALS AND METHODS

We prospectively included 110 asymptomatic subjects as part of a cohort study. Inclusion criteria were no knee pain in the last year. Exclusion criteria were any medical/surgical history of a knee disorder. Subjects underwent knee and low-dose posture radiographs [EOS®], 3 T MRI, clinical examination including muscle performance tests, and physical activity monitoring. The presence/absence of SPFP alterations (hyperintensity and mass effect) were assessed through consensus reading on fluid-sensitive sequences. Differences between groups of knees with SPFP alterations and controls were tested for a total of 55 categorical/continuous clinical/imaging parameters, including SPFP relative-T2-signal, trochlear/patellar/lower-limb morphologic measurements. Wilcoxon-rank-sum and chi-square tests were used to compare groups of patients. The histological correlation was obtained in a cadaveric specimen.

RESULTS

SPFP alterations were common in asymptomatic subjects: hyperintensity 57% (63/110) and mass effect 37% (41/110), with 27% (30/110) showing both. Among the 55 imaging, clinical, or activity parameters tested, only increased patellar tilt angle (p = 0.02) and TT-TG distance (p = 0.03) were statistically different between groups of SPFP alterations and controls. The histological correlation showed more abundant connective tissue in SPFP compared to the prefemoral fat pad.

CONCLUSIONS

SPFP hyperintensity and mass effect are common MRI findings in asymptomatic knees, and they are not related to most imaging, clinical, and activity parameters. Care should be taken not to overcall them pathological findings as they most likely represent normal variants.

Anatomical variations of the circle of Willis in children

BACKGROUND

The morphology of the circle of Willis in adults has been thoroughly discussed in scientific literature. However, the morphology of the circle of Willis in pediatric patients is under-researched.

OBJECTIVES

We aimed to establish reference data for the morphology and variations of the circle of Willis in a population consisting of all pediatric age subgroups and to evaluate the possible temporal evolution of the circle of Willis in pediatric patients along with the variations between pediatric and adult populations.

MATERIALS AND METHODS

Our patient cohort included 263 pediatric patients ages 1-215 months. A total of 273 magnetic resonance (MR) angiography images were retrospectively analyzed for all circle of Willis vessels to compare the incidence of complete cases and variation frequency based on gender and age group.

RESULT

In our study of 273 MR angiograms from all age ranges in the pediatric population, we found a 56.1% circle of Willis completion rate. Overall completion rates were statistically significantly higher in the toddler and preschool age groups. The lowest completion rate was in the newborn-infant group (40%).

CONCLUSION

Circle of Willis completion rates and variations in pediatric populations are similar to those in adult populations; completion rates rise in toddler and preschooler age groups and decline as children grow into the school-age and adolescent period.

Frequency of sternal variations and anomalies in living individuals evaluated by MDCT

PURPOSE

The aim of this retrospective study was to present the frequency and MDCT appearances of sternal variations and anomalies, as well as to highlight their clinical significance.

METHODS

This retrospective study was carried out on 1150 patients, who underwent chest MDCT. Axial planes, multiplanar and curved-planar reconstructed images were studied. Age and sex distribution of the variations was evaluated.

RESULTS

Anatomical variations of the sternum were found in 74.1%. The most frequent variation was the double-ended xiphoid process (36.9%), followed by the single xiphoidal foramen (25.8%) and the sternal sclerotic band (12.8%). Other variations observed were: sternal notch (10.1%), xiphoidal ligament calcification (8.3%), sternal foramen (4.9%), complete manubriosternal fusion (4.1%) and sternoxiphoidal fusion (4.1%), triple-ended xiphoid process (3.7%), sternal cleft (1.5%), whereas the rest of the variations including sternoxiphoidal junction pseudoforamen, suprasternal bone, pseudocleft, suprasternal tubercle and absence of xiphoid process were in less than 1%. In our subjects, sternal and xiphoidal foramina were adjacent to: the pericardium (37.14%), the diaphragm (22.9%), the mediastinal fat (17.1%), the liver (11.4%), the lung (8.5%) and to the stomach (2.9%).

CONCLUSIONS

Sternal variations are frequent, asymptomatic, detected incidentally at cross-sectional imaging and may be confused with pathologic conditions. Radiologists should be familiar with these variations in order to discriminate them from pathologies and avoid complications during interventional procedures.

ADVANCES IN KNOWLEDGE

This study presents thoroughly the sternal variations' MDCT appearance, detected in a Greek population, correlates them with age and gender and discuss their clinical significance in detail.

Cervicovertebral anomalies and/or normal variants in patients with congenitally bilateral absent maxillary lateral incisors

OBJECTIVE

To determine whether there is a relationship between congenitally bilaterally absent maxillary lateral incisors (BAMLIs) and skeletal anomalies and/or normal variants.

MATERIALS AND METHODS

The records of 86 patients (62 girls, 24 boys; age 12-17 years) with congenitally BAMLIs and 86 patients (55 girls, 34 boys; age 13-18 years) without any dental or skeletal anomalies were collected and evaluated retrospectively. The study was based on the evaluation of lateral cephalometric and orthopantomographic radiographs. Posterior arch deficiency of the atlas bone (PADA); atlanto-occipital ligament calcification, known as "ponticulus posticus" (PP); and interclinoid ligament calcification, known as "sella turcica bridging" were recorded for each participant. Pearson χ2 and Fisher exact tests were used to evaluate and compare skeletal anomalies and/or normal variants between patients with BAMLIs and the control group.

RESULTS

The prevalence of cervicovertebral anomalies and/or normal variants seen in the lateral cephalometric radiographs was higher in patients with BAMLI than in the control group. The prevalence of PP was lower and that of PADA was higher in patients with BAMLIs than in the control group (P < .05).

CONCLUSION

The prevalence of PADA was increased and that of PP formation was decreased in patients with BAMLIs. There was a significant relationship between skeletal anomalies and/or normal variants.

18F-FDG uptake in the normal appendix in adults: PET/CT evaluation

OBJECTIVE

This study aimed to determine the level of ¹⁸F fluorodeoxyglucose (¹⁸F-FDG) activity in the normal adult appendix using positron emission tomography/computed tomography (PET/CT).

MATERIALS AND METHODS

We performed a retrospective review of PET/CT images using ¹⁸F-FDG in 563 consecutive asymptomatic adult patients without appendiceal pathology. We excluded 257 patients for an undetected or obscured appendix and three patients for appendicitis found on CT imaging. FDG uptake in the appendix was qualitatively and quantitatively assessed. The maximum standardized uptake value (SUV_max) was calculated for quantitative analysis with SUV_max of the normal liver for comparison. A total of 303 patients (200 males, 103 females, mean age of 66 years) were included in this study. Medical charts and histories were evaluated for patients who showed positive FDG accumulation. Pearson's correlations between appendiceal SUV_max and age, body mass index, and blood glucose levels were analyzed.

RESULTS

The mean appendiceal SUV_max was 1.14 (range 0.52-5.12) with an appendix-to-liver SUV_max ratio of 0.34 (range 0.06-1.28). Three patients qualitatively showed a positive FDG accumulation with appendiceal SUV_max greater than 3.00. There were no correlations between appendiceal SUV_max and age, body mass index, or blood glucose levels.

CONCLUSIONS

FDG in the normal adult appendix shows a low activity level and is lower compared with normal liver. However, the normal appendix can rarely show high FDG accumulation. In such cases, differentiation from appendiceal pathology solely by PET/CT images would be difficult.

Child EEG (and maturation)

EEG changes during the perinatal period, infancy, childhood, and adolescence are concomitant with brain growth, myelination, expanding connectivity, and overall maturation, which are particularly fast during the first year of life. EEG aspects of early brain development are accessible in preterm during the third trimester of gestational age, and they evolve to full-term, infancy, and childhood EEG patterns. Each of these age periods shares specific EEG features that reach gross adult outlines in the first year. Interpreting EEG needs therefore a deep knowledge of pathological and normal EEG patterns with their variants belonging to each age range. Recording EEG during these periods also requires adapting the recording techniques to the specific age in order to obtain interpretable records. This chapter describes normal EEG features and variants, characteristic patterns of development, and some patterns that are unusual for age, from the neonatal period to adolescence.

Osteoporotic vertebral endplate and cortex fractures: A pictorial review

Despite years' research, the radiographic criteria for osteoporotic vertebral fracture and its grading remain debated. The importance of identifying vertebral endplate/cortex fracture (ECF) is being recognised; however, evaluation of osteoporotic ECF requires training and experience. This article aims to serve as a teaching material for radiologists/physicians or researchers to evaluate osteoporotic ECF. Emphasis is particularly dedicated to identifying ECF that may not be associated with apparent vertebral body collapse. We suggest a combined approach based on standardised radiologic evaluation by experts and morphometry measurement is the most appropriate approach to detect and classify osteoporotic vertebral fractures.

The translational potential

A good understanding of radiologic anatomy of vertebrae and fracture signs of endplate/cortex are essential for spine fragility fracture assessment.

Normal Variants and Pitfalls Encountered in PET Assessment of Gynecologic Malignancies

Combined PET/computed tomography is used for oncological indications. PET/computed tomography benefits from the metabolic information of PET and the anatomic localization of computed tomography. The integrated scanner provides data with accurate registration of anatomy and molecular information. Many physiologic conditions, normal variants, and benign lesions within the pelvis and the body can cause confusion and uncertainty. False-negative results owing to low ¹⁸F-fluorodeoxyglucose uptake from the tumor can produce diagnostic challenges and inaccurate conclusions. This article reviews normal variants and potential pitfalls encountered in PET assessment of gynecologic malignancies to provide useful information for the referring and reporting physicians.

A pictorial review of diagnostic pitfalls of developmental anomalies and variants in pancreatic imaging

Developmental anomalies and anatomic variants of the pancreas vary widely, and most of them are encountered incidentally during radiologic evaluation. However, some of these anomalies and variants are potentially pathologic and may cause various clinical presentations in childhood or adulthood. The early identification of these entities in various imaging modalities including ultrasound, computed tomography (CT), and magnetic resonance (MR) imaging would be valuable in making correct diagnoses and, in turn, preventing unnecessary additional procedures. In order to differentiate these entities, it is fundamental to understand the embryologic development and normal anatomical structure of the pancreas. In this article, we review the embryology and normal anatomy of the pancreas, and diagnostic pitfalls of developmental anomalies and anatomic variants in various pancreatic imaging modalities.

Articular Ultrasound in Asymptomatic Volunteers: Identification of the Worst Measures of Synovial Hypertrophy, Synovial Blood Flow and Joint Damage Among Small-, Medium- and Large-Sized Joints

Articular ultrasound of 6500 joint recesses was performed for the purpose of identifying which joint had the highest measurements among small-sized (SSJ), medium-sized (MSJ) and large-sized (LSJ) joints. Quantitative measurements of synovial hypertrophy (QSR) and semiquantitative measurements of synovial hypertrophy (SSH), power Doppler (SPD) and bone erosion (SBE) (score: 0-3) were made. Higher measurements (p < 0.01) of QSR were obtained in the second metatarsophalangeal joint (MTP), talonavicular joint, and hip. The highest SSH scores (2/3) were obtained in the second MTP, talonavicular joint, hip and knee; the highest SPD scores (1/2/3) in the first MTP, second MTP, dorsal second metacarpophalangeal (MCP) and radiocarpal recesses; and the highest SBE scores (2/3) in the radiocarpal, ulnocarpal and posterior recesses of the glenohumeral joint. In conclusion, higher measurements of synovial hypertrophy were found in the first and second MTPs (SSJ), talonavicular recess (MSJ) and hip (LSJ). Synovial blood flow was frequent in the first MTP and radiocarpal recess. Bone erosion stood out only in the glenohumeral joint.

Advanced practice physiotherapy in paediatric orthopaedics: innovation and collaboration to improve service delivery

INTRODUCTION

One in eight paediatric primary care presentations is for a musculoskeletal (MSK) disorder. These patients are frequently referred to paediatric orthopaedic surgeons; however, up to 50% of referrals are for normal variants. This results in excessive wait-times and impedes access for urgent surgical cases. Adult MSK medicine has successfully utilised advanced practice physiotherapists (APP) managing non-surgical candidates, with documented benefits both to patients and services. There is a gap in the literature with regard to APP in paediatric orthopaedics.

AIM

In this review, we investigate demands on paediatric orthopaedic services, examine the literature regarding APP in paediatric orthopaedics and explore the value the role has to offer current outpatient services.

RESULTS

Paediatric orthopaedic services are under-resourced with concurrent long wait times. Approximately 50% of referrals are for normal variants, which do not require specialist intervention. Poor musculoskeletal examination skills and low diagnostic confidence amongst primary care physicians have been identified as a cause of inappropriate referrals. APP clinics for normal variants have reported independent management rate and discharge rates of 95% and marked reduction in patient wait times.

CONCLUSION

There is limited evidence to support the APP in paediatric orthopaedics. Further studies are needed investigating diagnostic agreement, patient/stakeholder satisfaction, patient outcomes and economic evaluation. Paediatric orthopaedics is in crisis as to how to effectively manage the overwhelming volume of referrals. Innovative multidisciplinary solutions are required so that the onus is not solely on physicians to provide all services. The APP in paediatric orthopaedics may be part of the solution.

Variations in the Origin of Inferior Phrenic Arteries and Their Relationship to Celiac Axis Variations on CT Angiography

Objective

Knowing the origin of the inferior phrenic artery (IPA) is important prior to surgical interventions and interventional radiological procedures related to IPA. We aimed to identify variations in the origin of IPA and to investigate the relationship between the origin of IPA and celiac axis variations using computed tomography angiography (CTA).

Materials and Methods

The CTA images of 1000 patients (737 male and 263 female, the mean age 60, range 18–94 years) were reviewed in an analysis of IPA and celiac axis variations. The origin of IPA was divided into two groups, those originating as a common trunk and those originating independently without a truncus. The relationship between the origin of IPA and celiac axis variation was analyzed using Pearson's chi-square test.

Results

Both IPAs originated from a common trunk in 295 (29.5%) patients. From which the majority of the common trunk originated from the aorta. Contrastingly, the inferior phrenic arteries originated from different origins in 705 (70.5%) patients. The majority of the right inferior phrenic artery (RIPA) and the left inferior phrenic artery (LIPA) originated independently from the celiac axis. Variation in the celiac axis were detected in 110 (11%) patients. The origin of IPA was found to be significantly different in the presence of celiac axis variation.

Conclusion

The majority of IPA originated from the aorta in patients with a common IPA trunk, while the majority of RIPA and LIPA originating from the celiac axis in patients without a common IPA trunk. Thus, the origin of IPA may widely differ in the presence of celiac axis variation.

"Children are not small adults": avoiding common pitfalls of normal developmental variants in pediatric imaging

Imaging of children is complicated with a vast array of normal variants, congenital or developmental disorders, and age-dependent differential considerations. We present imaging findings of several common anatomic variants as well as physiological and maturational processes that occur in children. We compare and contrast them with pathological entities so that the reader can successfully distinguish them when interpreting pediatric imaging examinations. The content has been accrued from the authors' collective experience at a tertiary-care pediatric hospital, teaching and consulting with radiology trainees and clinicians, as well as a comprehensive review of the literature, and is intended to represent a useful error prevention tool for radiologists interpreting pediatric studies.

The efficacy of an extended scope physiotherapy clinic in paediatric orthopaedics

BACKGROUND

The demand for paediatric orthopaedic care is growing, and providing the service required is an increasingly challenging task. Physiotherapist-led triage clinics are utilised in adult orthopaedics to enable the provision of care to patients who may not require a surgical consult. The Physiotherapy Orthopaedic Triage Clinic (POTC) was established in Our Lady's Children's Hospital Crumlin in response to increasing demands on the paediatric orthopaedic service. The clinic is run by physiotherapists working in an advanced practice role (APP), and is the first paediatric clinic of its type and scale in the Republic of Ireland.

PURPOSE

To evaluate the efficacy of the service over the 3-year period from January 2011 to December 2013.

METHODS

A review of the prospectively gathered database was performed in order to establish the demographic profile of patients, investigate clinic outcomes, and evaluate the reduction in patient waiting times.

RESULTS

2650 patients were managed by the clinic over the 3-year period. A total of 77 % of patients were managed without consultant intervention. Fifty-three percent of patients were diagnosed as having a normal presentation. The mean waiting time reduced from 101.9 weeks pre-2010 to 15.4 weeks in 2013 for those patients managed by the POTC.

CONCLUSION

Since its inception, the clinic has significantly reduced waiting times for routine elective paediatric orthopaedic patients while managing the majority of patients independent of surgical opinion. This study shows that the APP can deliver high-quality care in the paediatric orthopaedic setting, benefitting both patients and service.

Erosion or normal variant? 4-year MRI follow-up of the wrists in healthy children

BACKGROUND

A large proportion of healthy children have wrist changes on MRI, namely carpal depressions, findings that have been described as pathological in children with juvenile idiopathic arthritis.

OBJECTIVE

We performed follow-up imaging in a cohort of healthy children to evaluate carpal surface depressions over time, focusing on the presence of overlying cartilage as a potential discriminator between normal variants and true erosions.

MATERIALS AND METHODS

74 of the initial cohort of 89 healthy children (83%) had a re-scan of their wrists using the same protocol, including coronal T1 and fat-saturated T2 sequences. A cartilage-selective sequence was added for this study. We registered number and location of bony depressions and presence of overlying cartilage.

RESULTS

The total number of carpal depressions increased by age group and over time; their location was unchanged in 370 of 487 (76%) carpal sites and 91 of 117 (78%) metacarpal sites. In total, 426 of the 1,087 (39.2%) bony depressions were covered by cartilage, with a decreasing percentage by age (P = 0.001).

CONCLUSION

Normal appearances during growth, such as bony depressions, should not be mistaken for pathology. There must be additional findings to support a diagnosis of disease. A cartilage sequence may add to the diagnostic image analysis.

Pelvis: normal variants and benign findings in FDG-PET/CT imaging

With the widespread use of whole-body fluorodeoxyglucose (FDG)-PET/computed tomography as a diagnostic tool in patients with cancer, incidental findings are of increasing importance. This is particularly true within the pelvis, where several benign findings might present with increased FDG uptake. In addition, physiologic excretion of radiotracer by way of the urinary tract can complicate image analysis. This article reviews potential incidental benign findings in the pelvis that one should be aware of when interpreting FDG-PET/computed tomography scans.