Magnetic resonance imaging predictors of shoulder instability in adolescents.

BACKGROUND: Managing recurrent shoulder instability in an athlete of any age is challenging. The pediatric literature regarding recurrence of instability is difficult to interpret because of the variable treatment protocols and varying ages. The adult literature suggests that bone loss on the humerus, glenoid or both, as detected by CT, has high rates of recurrence following surgical intervention. OBJECTIVE: The purpose of this study was to evaluate risk factors for recurrence following arthroscopic capsulorrhaphy in adolescent athletes using preoperative MR arthrograms. MATERIALS AND METHODS: We reviewed a retrospective shoulder instability database for adolescents (age ≤18 years), who underwent an isolated arthroscopic capsulorrhaphy from 2006 to 2011. We recorded preoperative MRI measurements regarding the dimensions of the glenohumeral joint, as well as glenoid, humeral and labral pathologies. We performed statistical analysis to determine MRI findings that might have predicted recurrence of shoulder instability following capsulorrhaphy. RESULTS: We reviewed a total of 50 patients (13-18 years) and found 22 patients (44%) to have recurrent instability following capsulorrhaphy. Presence of glenoid bone loss or a bipolar bone lesion (defined as bone loss on both the glenoid and humerus) significantly predicted recurrence of shoulder instability (both P=0.03). There was not a threshold size of glenoid bone loss or bipolar lesion that predicted recurrence. All remaining glenohumeral dimensions or presence or size of an isolated Hill-Sachs did not significantly predict recurrence of instability. CONCLUSION: Athletes ≤18 years old have a high rate of failure following arthroscopic capsulorrhaphy in the presence of glenoid bone loss or a bipolar lesion on MRI. Surgeons should consider addressing these lesions in adolescent athletes with shoulder instability. Additionally, MRI is a valid imaging tool to diagnose and measure osseous lesions of the shoulder.

Does abdominal pain duration affect the accuracy of first-line MRI for pediatric appendicitis?

PURPOSE: To compare the accuracy of first-line MRI for pediatric appendicitis between children with different durations of abdominal pain. MATERIALS AND METHODS: Between November 2012 and September 2013, 364 pediatric patients underwent MRI for clinically suspected appendicitis. Patients were stratified into one group with pain lasting less than or equal to 1 day and pain longer than 1 day. RESULTS: In patients with early abdominal pain, appendicitis occurred in 83 of 208 patients (39.9%) vs. 49 of 156 patients with pain longer than 1 day (31.4%, p = 0.09). Sensitivity and specificity of MRI in patients with early abdominal pain were 97.6% (95% CI [91.6%-99.3%]) and 94.4% (95% CI [88.9%-97.3%]), respectively, vs. 93.9% (95% CI [83.5%-97.9%]) and 97.2% (95% CI [92.1%-99.4%]), respectively, in patients with pain longer than 1 day in duration (p = 0.36 and p = 0.35 for sensitivity and specificity, respectively). CONCLUSIONS: First-line MRI is accurate for acute appendicitis in children presenting with early abdominal pain, and may be appropriate as the initial examination in children. Further prospective studies are needed to compare MRI vs. ultrasound as the initial examination in children with early abdominal pain to help further delineate a diagnostic imaging algorithm.

Diagnostic shortcomings of magnetic resonance arthrography to evaluate partial rotator cuff tears in adolescents.

BACKGROUND: Recent evidence suggests an increase in the incidence of partial articular-sided rotator cuff tears in adolescent athletes, but the accuracy of diagnostic studies has not been previously assessed in this cohort. This study was performed to assess the ability of magnetic resonance imaging with arthrography (MRIa) to diagnose partial rotator cuff (PRC) pathology in the adolescent age group. METHODS: All patients under the age of 19 years who underwent shoulder arthroscopy, between August 2008 and August 2010, were grouped based on the presence of a PRC tear diagnosed by either MRIa or arthroscopy. The control cohort included children without evidence of an intraoperative PRC. Surgical findings were then correlated with the preoperative MRIa findings and the accuracy of MRIa reading. Interclass coefficient was then determined for the MRIa reviewers. RESULTS: Thirty-one of 89 adolescents (mean age, 15.9 y; 36% girls and 64% boys) who underwent arthroscopic shoulder surgery were found to have radiographic or arthroscopic evidence of a PRC injury. There were 17 boys and 14 girls in the PRC group, with a mean age of 15.6 years. The PRC injuries involved either the supraspinatus tendon, infraspinatus tendon, or both. MRIa was 44% sensitive and 87% specific, with a positive predictive value of 64% and a negative predictive value of 74% with arthroscopic findings used as the gold standard. The ICC between reviewers was κ=0.57, with an absolute agreement of 84%. CONCLUSIONS: The overall diagnostic accuracy of the MRIa with regard to adolescent PRC injuries was 72%. MRIa was found to be specific, but not sensitive for the diagnosis of this pathology. The high false-negative rate seen in this adolescent cohort indicates that a PRC injury may be present even with a negative MRIa. Therefore, if clinical suspicion indicates a PRC injury, then the treating physician should consider management for rotator cuff pathology despite negative MRIa findings. LEVEL OF EVIDENCE: Level III--retrospective cohort study.

Diagnostic performance of contrast-enhanced MR for acute appendicitis and alternative causes of abdominal pain in children.

OBJECTIVE: Unenhanced MRI has emerged as a useful tool for diagnosing pediatric acute appendicitis. The use of contrast-enhanced MRI for diagnosing pediatric appendicitis has not been documented. The purpose of this study is to examine the diagnostic performance of contrast-enhanced MRI for acute appendicitis and alternative entities in the pediatric population presenting with acute abdominal pain. MATERIALS AND METHODS: A retrospective review was conducted of 364 consecutive pediatric patients undergoing contrast-enhanced MRI for the evaluation of possible appendicitis at a single institution between November 2012 and September 2013. RESULTS: There were 132 cases of pathologically confirmed appendicitis out of 364 pediatric patients (36.3%) included in the study. Overall sensitivity and specificity were 96.2% (95% CI [91.4-98.4%]) and 95.7% (95% CI [92.3-97.6%]), respectively. Positive predictive value and negative predictive value were 92.7% (95% CI [86.6-96.3%]) and 97.8% (95% CI [94.7-99.1%]), respectively. The appendix was visualized in 243 cases (66.8%). Imaging confirmed alternative diagnoses in 75 patients, including most commonly colitis, enteritis or terminal ileitis (n = 25, 6.9%), adnexal cysts (n = 25, 6.9%) and mesenteric adenitis (n = 7, 1.9%). CONCLUSION: Contrast-enhanced MRI is capable of accurately diagnosing acute appendicitis while detecting many alternative entities of abdominal pain, and it allows good visualization of the appendix. Further evaluation is needed to determine whether contrast-enhanced MRI provides an advantage over non-enhanced MRI for imaging evaluation of acute abdominal pain in the pediatric population.

The sensitivity of limited-sequence magnetic resonance imaging in identifying pediatric cervical spine injury: A Western Pediatric Surgery Research Consortium multicenter retrospective cohort study.

INTRODUCTION: Clinical clearance of a child's cervical spine after trauma is often challenging because of impaired mental status or an unreliable neurologic examination. Magnetic resonance imaging (MRI) is the criterion standard for excluding ligamentous injury in children but is constrained by long image acquisition times and frequent need for anesthesia. Limited-sequence magnetic resonance imaging (LSMRI) is used in evaluating the evolution of traumatic brain injury and may also be useful for cervical spine clearance while potentially avoiding the need for anesthesia. The purpose of this study was to assess the sensitivity and negative predictive value of LSMRI as compared with criterion standard full-sequence MRI as a screening tool to rule out clinically significant ligamentous cervical spine injury. METHODS: We conducted a 10-center, 5-year retrospective cohort study (2017-2021) of all children (0-18 years) with a cervical spine MRI after blunt trauma. Magnetic resonance imaging images were rereviewed by a study pediatric radiologist at each site to determine if the presence of an injury could be identified on limited sequences alone. Unstable cervical spine injury was determined by study neurosurgeon review at each site. RESULTS: We identified 2,663 children younger than 18 years who underwent an MRI of the cervical spine with 1,008 injuries detected on full-sequence studies. The sensitivity and negative predictive value of LSMRI were both >99% for detecting any injury and 100% for detecting any unstable injury. Young children (younger than 5 years) were more likely to be electively intubated or sedated for cervical spine MRI. CONCLUSION: Limited-sequence magnetic resonance imaging is reliably detects clinically significant ligamentous injury in children after blunt trauma. To decrease anesthesia use and minimize MRI time, trauma centers should develop LSMRI screening protocols for children without a reliable neurologic examination. LEVEL OF EVIDENCE: Diagnostic Test/Criteria; Level III.

Lymph-node-first presentation of Kawasaki disease compared with bacterial cervical adenitis and typical Kawasaki disease.

OBJECTIVE: To identify characteristics differentiating the node-first presentation of Kawasaki disease (NFKD) from bacterial cervical lymphadenitis (BCL) and typical Kawasaki disease (KD). STUDY DESIGN: From our prospectively collected database, we compared clinical, laboratory, and imaging characteristics of NFKD and BCL cohorts and performed multivariable logistic regression to identify variables that distinguish NFKD from BCL. We then compared outcomes of patients with NFKD and patients with typical KD treated during the same period. RESULTS: Over 7 years, 57 patients were hospitalized for NFKD, 78 for BCL, and 287 for typical KD. Patients with NFKD were older and had more medical encounters and longer duration of illness before the correct diagnosis was made than did patients with BCL. Of patients with NFKD, 33% had an admission diagnosis of bacterial adenitis or abscess. Compared with patients with BCL, patients with NFKD had lower leukocyte (white blood cell), hemoglobin, and platelet counts and higher absolute band counts (ABCs), C-reactive protein (CRP), alanine transaminase and γ-glutamyl transpeptidase levels, and erythrocyte sedimentation rates. In the multivariable analysis, smaller nodes, lower white blood cell count, and higher ABC and CRP were independently associated with NFKD. Patients with NFKD had multiple enlarged solid nodes and comparable rates of retropharyngeal edema. Compared with patients with typical KD, patients with NFKD were older, had more severe inflammation, and had similar rates of coronary artery abnormalities and resistance to intravenous immune globulin. CONCLUSIONS: High ABC and CRP values and multiple enlarged solid nodes in febrile patients with cervical adenopathy should prompt consideration of NFKD to prevent delayed diagnosis of KD. Retropharyngeal edema on radiography should not dissuade from the diagnosis of NFKD.

Lateral center-edge angle on conventional radiography and computed tomography.

BACKGROUND: Lateral center-edge angle (LCEA), originally described and validated on AP radiographs, has been used increasingly in CT-based studies, but it is unclear whether the measure is reliable and whether it correlates with that on AP radiographs. QUESTION/PURPOSES: We therefore determined: (1) the interobserver and intraobserver reliabilities of the LCEA measured on AP radiographs; (2) the interobserver and intraobserver reliabilities of the LCEA measured on CT scans; and (3) the intermodality correlation of the LCEA between CT and AP radiography. METHODS: We reviewed the AP radiographs and CT scans of 22 patients treated for slipped capital femoral epiphyses. CT scans were reoriented to a neutral pelvic tilt and inclination. Three evaluators measured the LCEA on the unaffected hip on the AP and CT coronal images that corresponded to the center of the acetabulum on the axial slice. RESULTS: We found an interobserver intraclass correlation (ICC) analysis of 0.84 for the AP radiographs and 0.88 for the CT scans. The intraobserver ICC for the AP radiographs was 0.96, and for the CT scans 0.98. The intermodality ICC for the CT scans and AP radiographs was 0.79, with a lower bound of 0.61 and an upper bound of 0.87. CONCLUSIONS: Our data suggest the LCEA measured on a CT scan is reliable and correlates with the LCEA on AP radiographs.

MRI for the evaluation of pectus excavatum.

Pectus excavatum, the most common congenital deformity of the anterior chest wall, is both a cosmetic and functional abnormality. The degree of abnormal chest wall deformity determines its functional effect, particularly its cardiac and pulmonary impact. Although CT scanning is the most widely used cross-sectional imaging technique used to measure the Haller index, the radiation exposure is reason to seek other alternatives. At our institution, we have introduced a rapid MRI technique for this purpose, which utilizes a single-axial 2-D FIESTA acquisition.

The role of computed tomography and magnetic resonance imaging for preoperative pediatric cochlear implantation work-up in academic institutions.

OBJECTIVE: The goal of the study is to investigate the association of pertinent preoperative temporal bone computed tomography (CT) and brain magnetic resonance imaging (MRI) results and intraoperative surgical findings and complications of pediatric cochlear implantation reported in academic settings. METHODS: This is a retrospective review of cochlear implant patients who received a pre-operative temporal bone CT and MRI of the brain between 2005 and 2012 at academic pediatric otolaryngology practices within children's hospitals in the United States and France. Scans were reviewed in a double-blind fashion and compared to intraoperative findings. RESULTS: 91 children were analyzed (mean age 5.54 +/- 0.58 years). A small facial recess identified on CT was associated with difficult insertion of electrodes (P = 0.0003). A prominent sigmoid sinus noted on CT was associated of difficult insertion of electrodes (P = 0.01), iatrogenic tegmen dehiscence (P = 0.005), as well as difficult round window access (P = 0.025). No specific CT finding was found to be associated with external auditory canal injury, perilymphatic gusher, or iatrogenic facial nerve injury. MRI brain and internal auditory canal findings were not predictive of surgical outcomes. CONCLUSIONS: Preoperative CT and MRI remain an important planning tool for pediatric cochlear implantation, particularly in academic institutions. The findings of our study demonstrate that a detailed assessment of both preoperative CT and MRI are valuable for teaching and surgical planning.

Are the Current Little League Pitching Guidelines Adequate? A Single-Season Prospective MRI Study.

BACKGROUND: Little League throwing guidelines have recently been implemented in an attempt to lessen the growing number of elbow injuries occurring in youth baseball players. HYPOTHESIS/PURPOSE: The purpose of this study was to examine pre- and postseason changes seen on magnetic resonance imaging (MRI) in youth baseball players' elbows in an attempt to identify risk factors for pain and MRI abnormalities, with a particular focus on the current Little League guidelines. We hypothesized that MRI abnormalities would be common in pitchers with high pitch counts and poor guideline compliance. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: A prospective study of Little League players aged 10 to 13 years was performed. Players were recruited prior to the start of the season and underwent bilateral elbow MRI as well as a physical examination and completed a questionnaire addressing their playing history and arm pain. At the end of the season, a repeat MRI and physical examination were performed. MRIs were read by blinded radiologists. During the season, player statistics including innings played, pitch counts, and guideline compliance were recorded. Physical examination findings and player statistics were compared between subjects with and without MRI changes utilizing chi-square and analysis of variance techniques. RESULTS: Twenty-six players were enrolled. Despite 100% compliance with pitching guidelines, 12 players (48%) had abnormal MRI findings, and 28% experienced pain during the season. There was a significant difference in distal humeral physeal width measured pre- to postseason (1.54 vs 2.31 mm, P < .001). There was a significant loss of shoulder internal rotation during the season, averaging 11°. While pitch counts, player position, and throwing curveballs/sliders were not significantly associated with changes seen on MRI, year-round play was associated with abnormalities (P < .05). Much lower compliance (<50%) was observed with nonenforced guidelines, including avoidance of single-sport specialization, year-round play, and throwing curveballs/sliders. CONCLUSION: Arm pain and MRI abnormalities of the medial elbow are common in Little League baseball players who comply with the Little League throwing guidelines, especially those playing year-round.

Preseason Assessment of Radiographic Abnormalities in Elbows of Little League Baseball Players.

BACKGROUND: Youth baseball has been associated with elbow pain and elbow abnormalities, leading to the implementation of throwing and pitching guidelines. The purpose of the current study was to examine elbow abnormalities on magnetic resonance imaging (MRI) in asymptomatic Little League baseball players and to correlate these findings with the players' throwing history and physical examinations. METHODS: A prospective study of Little League players who were 10 to 13 years of age was performed. Players were recruited prior to the start of the season and underwent bilateral elbow MRI. All players underwent a physical examination and responded to a questionnaire addressing their playing history and any arm pain. The MRIs were read by 2 radiologists. Responses on the questionnaire and physical examination findings were compared between subjects with and without positive MRI findings utilizing chi-square and analysis of variance techniques. RESULTS: Twenty-six players were enrolled. The majority (77%) were right-handed and 14 (54%) were a pitcher and/or catcher. Nine players (35%) had 12 positive MRI findings: 7 findings of edema or signal change of the medial epicondyle apophysis, 2 findings of fragmentation of the medial epicondyle, and 3 findings of edema or signal change of the sublime tubercle. The prevalence of positive MRI findings and a history of arm pain were not greater in pitchers and catchers compared with other players. Players with a positive MRI finding demonstrated greater reduction in shoulder internal rotation (12°) compared with the nondominant arm (3°) (p = 0.04). The two factors associated with a positive MRI finding were year-round play (47% of year-round players compared with 11% of non-year-round players; p < 0.01) and working with a private coach (71% compared with 21%; p = 0.02). Additionally, a history of pain was associated with year-round play and a private coach (p < 0.05). CONCLUSIONS: MRI abnormalities involving the medial aspect of the elbow are common in year-round Little League baseball players, especially those with internal rotation deficits and private coaches. Although Little League guidelines potentially lessen abnormalities seen in pitchers, further refinement of these guidelines addressing year-round play, pain, and private coaching should be considered. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Acute pediatric encephalitis neuroimaging: single-institution series as part of the California encephalitis project.

PURPOSE: Diagnosing pediatric encephalitis is challenging because of varied clinical presentation, nonspecific neuroimaging features, and rare confirmation of causality. We reviewed acute neuroimaging of children with clinically suspected encephalitis to identify findings that may correlate with etiology and length of stay. METHODS: Imaging of 141 children with clinically suspected encephalitis as part of The California Encephalitis Project from 2005 to 2012 at a single institution was reviewed to compare the extent of neuroimaging abnormalities to patient age, gender, length of stay, and unknown, possible, or confirmed pathogen. Scan review was blinded and categorized by extent and distribution of abnormal findings. RESULTS: Abnormal findings were evident on 23% (22/94) of computed tomography and 50% (67/134) of magnetic resonance imaging studies in the acute setting. Twenty children with normal admission computed tomography had abnormal findings on magnetic resonance imaging performed within 2 days. Length of stay was significantly longer among children with abnormal acute magnetic resonance imaging (P < 0.001) and correlated with increased complexity (Spearman rho = 0.4, P < 0.001) categorized as: no imaging abnormality, meningeal enhancement and/or focal nonenhancing lesion, multifocal lesions, confluent lesions, and lesions plus diffusion restriction, hemorrhage, or hydrocephalus. There was no correlation between neuroimaging findings and an identifiable pathogen (P = 0.8). CONCLUSION: Abnormal magnetic resonance imaging findings are more common than abnormal computed tomography findings in pediatric encephalitis. Increasing complexity of magnetic resonance imaging findings correlated with disease severity as evidenced by longer length of stay, but were not specific for an identifiable pathogen using a standardized diagnostic encephalitis panel.

Imaging Pediatric Vascular Lesions.

Vascular anomalies are commonly encountered in pediatric and dermatology practices. Most of these lesions are benign and easy to diagnose based on history and clinical exam alone. However, in some cases the diagnosis may not be clear. This may be of particular concern given that vascular anomalies may occasionally be associated with an underlying syndrome, congenital disease, or serious, life-threatening condition. Defining the type of vascular lesion early and correctly is particularly important to determine the optimal approach to management and treatment of each patient. The care of pediatric patients often requires collaboration from a multitude of specialties including pediatrics, dermatology, plastic surgery, radiology, ophthalmology, and neurology. Although early characterization of vascular lesions is important, consensus guidelines regarding the evaluation and imaging of vascular anomalies does not exist to date. Here, the authors provide an overview of pediatric vascular lesions, current classification systems for characterizing these lesions, the various imaging modalities available, and recommendations for appropriate imaging evaluation.

Breast Imaging-Reporting and Data System (BI-RADS) classification in 51 excised palpable pediatric breast masses.

INTRODUCTION: The American College of Radiology Breast Imaging Reporting and Data System (BI-RADS) classification was developed to risk stratify breast lesions and guide surgical management based on imaging. Previous studies validating BI-RADS for US do not include pediatric patients. Most pediatric breast masses present as palpable lesions and frequently undergo ultrasound, which is often accompanied with a BI-RADS classification. Our study aimed to correlate BI-RADS with pathology findings to assess applicability of the classification system to pediatric patients. METHODS: We performed a retrospective review of all patients who underwent excision of a breast mass at a single center from July 2010 to November 2013. We identified all patients who underwent preoperative ultrasound with BI-RADS classification. Demographic data, imaging results, and surgical pathology were analyzed and correlated. RESULTS: A total of 119 palpable masses were excised from 105 pediatric patients during the study period. Of 119 masses, 81 had preoperative ultrasound, and BI-RADS categories were given to 51 masses. Of these 51, all patients were female and the average age was 15.9 years. BI-RADS 4 was given to 25 of 51 masses (49%), and 100% of these lesions had benign pathology, the most common being fibroadenoma. CONCLUSIONS: Treatment algorithm based on BI-RADS classification may not be valid in pediatric patients. In this study, all patients with a BI-RADS 4 lesion had benign pathology. BI-RADS classification may overstate the risk of malignancy or need for biopsy in this population. Further validation of BI-RADS classification with large scale studies is needed in pediatric and adolescent patients.

An analysis of cervical spine magnetic resonance imaging findings after normal computed tomographic imaging findings in pediatric trauma patients: ten-year experience of a level I pediatric trauma center.

BACKGROUND: A variety of radiologic screening protocols exist for evaluation of pediatric trauma patients with potential cervical spine (c-spine) injuries. The purpose of this study was to describe findings on c-spine magnetic resonance imaging (MRI) after previously normal c-spine computed tomographic (CT) scan findings at a Level 1 trauma center. METHODS: A retrospective chart review of trauma patients evaluated at Rady Children's Hospital, San Diego, between January 2000 and February 2010 was conducted. Trauma patients who were younger than 18 years, placed in c-spine precautions, had a normal c-spine CT scan, who subsequently had a c-spine MRI were included. The sample was subdivided into patients who underwent CT scans between January 1, 2000 to July 31, 2005 (early group), and August 1, 2005 to February 28, 2010 (late group), to compare results between different CT scan resolutions. RESULTS: A total of 173 patients met inclusion criteria. With 100% of patients demonstrating normal c-spine CT scan findings, 83% of c-spine MRI findings were also negative (p < 0.001). Thirty patients (17%) demonstrated significant abnormalities on MRI. Of the 30, 5 (2.9%) required operative c-spine stabilization. Eighty-five patients underwent CT scan in the early group, and 88 in the late group. All 5 patients with unstable injuries not discovered on CT scan were from the early group, compared with none in the late group (p = 0.027). CONCLUSION: Our results suggest that high-resolution CT scan with sagittal and coronal reconstructions may be comparable with MRI for the detection of unstable c-spine injuries in pediatric trauma patients. Although minimizing CT scan radiation exposure remains essential, high-resolution c-spine CT scan may allow for earlier c-spine clearance with reduction of associated hard collar comorbidities in centers where MRI is not available or in situations where the patient's clinical stability precludes obtaining MRI. LEVEL OF EVIDENCE: Diagnostic study, level III.