Normocephalic sagittal craniosynostosis in young children is common and unrecognized.

OBJECTIVE: Sagittal craniosynostosis (SC) is usually diagnosed during early childhood by the presence of scaphocephaly. Recently, our group found 3.3% of children under 5 years of age with normocephalic sagittal craniosynostosis (NSC) using computed tomography (CT) scans. This paper aims to validate our preliminary findings using a larger cohort of patients, and analyze factors associated with incidental NSC. METHODS: A retrospective review of head CT scans in patients aged 0 to 71 months who presented to the emergency department of our tertiary care institution between 2008 and 2020 was completed. Patients with syndromes associated with craniosynostosis (CS), history of hydrocephalus, or other brain/cranial abnormalities were excluded. Two craniofacial surgeons reviewed the CT scans to evaluate the presence and extent of CS. Demographic information, gestational age, past medical and family history, medications, and chief complaint were recorded as covariates, and differences between patients with and without CS were analyzed. Furthermore, comparison of the prevalence of CS across age groups was studied. Additional analysis exploring association between independent covariates and the presence of CS was performed in two sub-cohorts: patients ≤ 24 months of age and patients > 24 months of age. RESULTS: A total of 870 scans were reviewed. SC was observed in 41 patients (4.71% - 25 complete, 16 incomplete), all with a normal cranial index (width/length > 0.7). The prevalence of SC increased up to 36 months of age, then plateaued through 72 months of age. Patients under 2 years of age with family history of neurodevelopmental disease had 49.32 (95% CI [4.28, 567.2]) times higher odds of developing CS. Sub-cohort of patients above 24 months of age showed no variable independently predicted developing CS. CONCLUSION: NSC in young children is common. While the impact of this condition is unknown, the correlation with family history of neurodevelopmental disease is concerning.

Non-ionic CT contrast solutions rapidly alter bovine cartilage and meniscus mechanics.

OBJECTIVE: To evaluate effects of a common CT contrast agent (iohexol) on the mechanical behaviors of cartilage and meniscus. METHODS: Indentation responses of juvenile bovine cartilage and meniscus were monitored following exposure to undiluted contrast agent (100% CA), 50% CA/water, 50% CA/Phosphate Buffered Saline (PBS) or PBS alone, and during re-equilibration in PBS. The normalized peak force (Fpk¯), effective osmotic strain (εosm), and normalized effective contact modulus (Ec¯) were calculated for every cycle, with time constants determined for both exposure and recovery via mono- or biexponential fits to Fpk¯. RESULTS: All cartilage CA groups exhibited long-term increases in Fpk¯ following exposure, although the hyperosmolal 100% CA and 50% CA/PBS groups showed an initial transient decrease. Meniscus presented opposing trends, with decreasing Fpk¯ for all CA groups. Re-equilibration in PBS for 1hr after exposure to 100% CA produced recovery to baseline Fpk¯ in cartilage but not in meniscus, and extended tests indicated that meniscus required ∼2.5 h to recover halfway. Ec¯ increased with CA exposure time for cartilage but decreased for meniscus, suggesting an increased effective stiffness for cartilage and decreased stiffness for meniscus. Long-term changes to εosm in both tissues were consistent with changes in Ec¯. CONCLUSION: Exposure to iohexol solutions affected joint tissues differentially, with increased cartilage stiffness, likely relating to competing hyperosmotic and hypotonic interactions with tissue fixed charges, and decreased meniscus stiffness, likely dominated by hyperosmolarity. These altered tissue mechanics could allow non-physiological deformation during ambulatory weight-bearing, resulting in an increased risk of tissue or cell damage.

Desmopressin for nocturnal enuresis: urinary osmolality and response.

OBJECTIVE: To measure the effect of intranasal desmopressin (l-deamino 8-D-arginine vasopressin, DDAVP) on urine osmolality in a group of patients with persistent primary enuresis, and to determine whether changes in osmolality can the predict response to treatment. PATIENTS AND METHODS: Thirty-seven patients with persistent primary nocturnal enuresis were entered into a double-blind placebo-controlled crossover trial of 20 micrograms intranasal DDAVP spray. Morning urinary osmolality was measured on two occasions during each phase of treatment and the clinical response recorded in a diary. RESULTS: Thirty-one patients (22 males and nine females) were evaluable at the end of the trial period. A good clinical response, defined as enuresis on two nights or fewer each week, occurred in 12 of 31 (39%) patients, but complete continence was attained in only two. The response was better in older patients and in those with less frequent enuresis. The mean and peak urinary osmolality of the morning urine samples were higher while on treatment with DDAVP compared with placebo, but this difference was not statistically significant and the response did not predict a good clinical outcome in improving the enuresis. CONCLUSIONS: Treatment with DDAVP can produce a socially acceptable level of dryness in some patients with refractory nocturnal enuresis. However, the early morning urinary osmolality, as a reflection of changes in nocturnal osmolality, was not useful in distinguishing this group or in selecting those who will respond to treatment.