Asymptomatic intraspinal epidermoid cyst in a 7-year-old male with juvenile idiopathic arthritis identified by an advanced physiotherapist practitioner: a case report.

BACKGROUND: Pediatric intraspinal epidermoid cysts are rare with potential to cause life-altering outcomes if not addressed. Reports to date describe symptomatic presentations including loss of bladder or bowel function and motor and sensory losses. This case report identifies the diagnostic challenge of an asymptomatic intraspinal epidermoid cyst in the cauda equina region presenting in a 7-year-old male with juvenile idiopathic arthritis (JIA). DIAGNOSIS: An advanced physiotherapist practitioner assessed and diagnosed a previously healthy 7-year-old-male of South Asian descent with JIA based on persistent knee joint effusions. Complicating factors delayed the investigation of abnormal functional movement patterns, spinal and hip rigidity and severe restriction of straight leg raise, all atypical for JIA. Further delaying the diagnosis was the lack of subjective complaints including no pain, no reported functional deficits, and no neurologic symptoms. A spinal MRI investigation 10-months from initial appointment identified intraspinal epidermoid cysts occupying the cauda equina region requiring urgent referral to neurosurgery. DISCUSSION: Clinical characteristics and pattern recognition are essential for diagnosing spinal conditions in pediatric populations. Diagnostic challenges present in this case included co-morbidity (JIA), a severe adverse reaction to treatment, a lack of subjective complaints and a very low prevalence of intraspinal epidermoid cysts. IMPACT STATEMENTS: Early signs of pediatric asymptomatic intraspinal epidermoid cysts included abnormal functional movement patterns, rigidity of spine, severely limited straight leg raise and hip flexion without pain. Advanced physiotherapist practitioners can be integral to pediatric rheumatology teams considering their basic knowledge in musculoskeletal examination and functional mobility assessment when identifying rare spinal conditions that present within the complex context of rheumatic diseases.

Understanding the diagnosis of superior mesenteric artery syndrome: analysis of the location of duodenal impression on upper gastrointestinal studies.

BACKGROUND: Upper gastrointestinal (GI) contrast studies are frequently requested to aid superior mesenteric artery syndrome diagnosis, a rare entity. Compression of the third duodenal part is expected to be mid-to-left of the midline where the superior mesenteric artery arises from the aorta; however, a duodenal impression to the right of the midline due to normal anatomic impression by the inferior vena cava (IVC) is often encountered and frequently misdiagnosed. OBJECTIVE: The purpose of this study was to determine the frequencies of (1) normal right-of-midline duodenal impressions and (2) mid-to-left of midline compressions in upper GI studies in a tertiary pediatric referral center. MATERIALS AND METHODS: All upper GI studies performed at our institution over 2 years were retrospectively evaluated to determine whether the duodenum had vertical duodenal impression to the right of the vertebral midline, mid-to-left of the vertebral midline, or no identifiable duodenal impression at all. RESULTS: In total, 538 upper GI studies were included in this analysis. A total of 275 male and 247 female patients between 0 and 17 years of age (median: 6 years, range: 1 month-17 years) were included. Of 538 total upper GI studies, there were 240 studies (44.6%) with a right-of-midline impression. There were only 10 studies (1.9%) with a mid-to-left of midline compression, and 9/10 also showed a concurrent right-sided impression sign. CONCLUSION: Right-of-midline duodenal impression is a normal anatomic finding caused by the IVC and should not be confused with superior mesenteric artery syndrome. In the presence of an appropriate clinical context, proximal duodenal dilation, "to-and-fro" motion of contrast, and duodenal impression at mid-to-left of midline, a diagnosis of superior mesenteric artery syndrome should be considered.

A comparison of sagittal MRI and lateral radiography in determining the Insall-Salvati ratio and diagnosing patella alta in the pediatric knee.

BACKGROUND: The Insall-Salvati ratio is a technique for determining patellar height that relies on bony landmarks. Magnetic resonance imaging (MRI) and plain radiography are used interchangeably to assess the Insall-Salvati ratio in the pediatric population despite the lack of validity in the literature. OBJECTIVE: The purpose of this study was to investigate if the Insall-Salvati ratio and patella alta as determined on MRI are comparable to those determined on radiography in pediatric patients. MATERIALS AND METHODS: We conducted a retrospective review of 49 pediatric patients (age range: 7.5-17.0 years) with unfused growth plates who underwent both knee MRI and lateral knee radiography. Measurements for calculating the Insall-Salvati ratio (the ratio of patella tendon length to patella length) were obtained by three observers. Data were analyzed using paired t-tests and Pearson's correlation. A reliability assessment and inter-method agreements were performed. Patella alta was defined as an Insall-Salvati ratio > 1.2. Additional cutoffs of Insall-Salvati ratios > 1.3 and > 1.4 were also analyzed. RESULTS: There was no statistically significant difference between Insall-Salvati ratio as determined on MRI (mean: 1.20) and radiographs (mean: 1.25; P > 0.05). There was a strong correlation between Insall-Salvati ratio as determined on MRI and radiographs (Pearson's r = 0.6) with moderate consistency (Cronbach's alpha = 0.78). There was a good level of agreement between the diagnosis of patella alta on MRI and radiographs when defined as an Insall-Salvati ratio greater than 1.2 and 1.3 (Cohen's kappa = 0.61). CONCLUSION: The results demonstrate a strong association between Insall-Salvati ratio and patella alta derived from MRI and radiographs in children ages 7.5 years and older.

Metal Artifact Reduction: Added Value of Rapid-Kilovoltage-Switching Dual-Energy CT in Relation to Single-Energy CT in a Piglet Animal Model.

OBJECTIVE: The purpose of this article is to evaluate virtual monochromatic spectral imaging and metal artifact reduction software for reducing metal artifact and to compare it with conventional single-energy CT (SECT) in an animal model. MATERIALS AND METHODS: Postmortem juvenile (n = 5) and adult (n = 1) swine specimens were scanned with SECT followed by a dual-energy CT (DECT) pediatric protocol after the insertion of two rods into their paraspinal thoracolumbar regions. Virtual monochromatic spectral images were extrapolated from DECT images at five monoenergetic levels (64, 69, 75, 88, and 105 keV) with and without the use of metal artifact reduction software. Images were evaluated by a 5-point scoring system for the extent of metallic artifacts and image interpretability in soft-tissue and bone windows. The density in the most pronounced artifact was measured. CT dose index was recorded. RESULTS: In studies without metal artifact reduction software, higher energy reconstructions resulted in fewer artifacts and better image interpretability in both soft-tissue and bone windows (p < 0.0001). Artifact density decreased from -792 HU at 64 keV to -128 HU at 105 keV without the use of metal artifact reduction software. No difference was noted in attributes' scores or in artifact density in studies using metal artifact reduction software (p > 0.05). DECT studies showed lower scores compared with SECT with regard to all attributes. A new faint perimetallic hypodense halo was seen in all studies with metal artifact reduction software. The CT dose index of DECT was 1.18-3.56 times higher than that of SECT techniques. CONCLUSION: DECT at all energy levels with metal artifact reduction software and higher energy extrapolations without metal artifact reduction software reduced metallic artifact and enhanced image interpretability compared with SECT. Radiation dose with DECT could be significantly higher than SECT.

Uncommon incidental pseudoaneurysm. Diagnostic and management challenges.

OBJECTIVE: To analyze patients with uncommon incidental pseudoaneurysms, secondary to non-catheterization causes, and to discuss the peculiar clinical spectrum, and focus on some aspects of difference from post-catheterization pseudoaneurysms. METHODS: Eleven patients, 8 males and 3 females, were studied retrospectively in Jordan University Hospital, Amman, Jordan, between 2002-2008. Radiological studies performed included duplex sonography (DS), computed tomography (CT), conventional angiography, magnetic resonance imaging (MRI), and magnetic resonance angiography (MRA). RESULTS: Pseudoaneurysms were most commonly encountered in young males (63.6%), especially in the lower limb vessels (36%). Clinical findings were suggestive of pseudoaneurysms in 27% of our cases. Four out of the 8 DS scans showed the neck of pseudoaneurysms, and the to and fro waveform, the strongest indicators for pseudoaneurysms. Both CT with intravenous contrast and angiography failed to establish the diagnosis in one out of 5 cases. The MRI with MRA showed the pseudoaneurysms in 2 patients that underwent the scan. CONCLUSION: Incidental pseudoaneurysms are considered following iatrogenic procedures, penetrating, or blunt traumas with variable delay time. Young healthy males are at increased risks, as opposed to elderly females with calcified vessels in post-catheterization cases. Duplex sonography is less sensitive in incidental than post-catheterization pseudoaneurysms. The CT scan with intravenous contrast has high accuracy in establishing the diagnosis in small, or medium sized pseudoaneurysms. The MRI and MRA are accurate valuable studies and comparable to conventional angiography.