STRANGULATION-INDUCED ATLANTOAXIAL ROTATORY SUBLUXATION TREATED WITH CLOSED REDUCTION.

BACKGROUND: Cervical subluxation is a broad class of injuries in which there are degrees of misalignment of vertebral bodies in relationship to adjacent vertebra. Atlantoaxial rotatory subluxation (AARS) is a subtype of cervical subluxation resulting from exaggerated rotation of the C1-C2 complex. Inflammatory, infectious, post-surgical, and traumatic etiologies are recognized and well-described. AARS is predominantly seen in children and occurs rarely in adults. CASE REPORT: We submit the case of an otherwise healthy adult male patient presenting to the emergency department with strangulation-induced C1-C2 subluxation with a rotational component that was treated at the bedside by neurosurgery with closed reduction. Why Should an Emergency Physician Be Aware of This? Clinicians must consider a broad range of serious pathologies in a patient presenting with torticollis, especially in the setting of strangulation. Although extremely rare in adults, AARS must be considered in the differential diagnosis, as early identification increases the likelihood of successful nonoperative treatment.

Dissolved organic matter transformations in a freshwater rivermouth.

River-to-lake transitional areas are biogeochemically active ecosystems that can alter the amount and composition of dissolved organic matter (DOM) as it moves through the aquatic continuum. However, few studies have directly measured carbon processing and assessed the carbon budget of freshwater rivermouths. We compiled measurements of dissolved organic carbon (DOC) and DOM in several water column (light and dark) and sediment incubation experiments conducted in the mouth of the Fox river (Fox rivermouth) upstream from Green Bay, Lake Michigan. Despite variation in the direction of DOC fluxes from sediments, we found that the Fox rivermouth was a net sink of DOC where water column DOC mineralization outweighed the release of DOC from sediments at the rivermouth scale. Although we found DOM composition also changed during our experiments, alterations in DOM optical properties were largely independent of the direction of sediment DOC fluxes. We found a consistent decrease in humic-like and fulvic-like terrestrial DOM and a consistent increase in the overall microbial composition of rivermouth DOM during our incubations. Moreover, greater ambient total dissolved phosphorus concentrations were positively associated with the consumption of terrestrial humic-like, microbial protein-like, and more recently derived DOM but had no effect on bulk DOC in the water column. Unexplained variation indicates that other environmental controls and water column processes affect the processing of DOM in this rivermouth. Nonetheless, the Fox rivermouth appears capable of substantial DOM transformation with implications for the composition of DOM entering Lake Michigan. Supplementary Information: The online version contains supplementary material available at 10.1007/s10533-022-01000-z.

Imaging of Fibrous Dysplasia Protuberans, an Extremely Rare Exophytic Variant of Fibrous Dysplasia.

This paper details the case report of a 26-year-old man who presented with a growing right-sided skull mass evaluated with ultrasound, non-contrast CT, contrast-enhanced MRI and 99mTc-MDP whole body bone scan with SPECT/CT. These studies suggested a broad differential diagnosis favoring benign osseous lesions. Given a more recent increase in the rate of growth, headache and large size, the lesion was excised via craniotomy followed by cranioplasty. Pathology confirmed fibrous dysplasia (FD) as the diagnosis. Interestingly, this report is the imaging evaluation of the exophytic subtype of FD, the so-called FD protuberance, an extremely rare variant of FD, of which only two case reports are found in the literature.

Utility of susceptibility weighted imaging (SWI) and pseudo-continuous arterial spin labeling (pCASL) in diagnosis of falcine venous thrombosis in a child with transient ischemic attack.

Pediatric stroke and transient ischemic attack (TIA) are uncommon but true emergencies with a wide differential diagnosis. Diagnostic imaging plays a critical role in differentiating the diverse range of etiologies. In this case, we report a 3-year-old female with no medical history who developed acute neurological deficits and demonstrate how adjunct advanced imaging including susceptibility weighted imaging (SWI) and pseudo-continuous arterial spin labeling (pCASL) can play a significant diagnostic role in the emergent setting. Imaging was performed with a Philips Ingenia 3.0T MRI. MRI brain, MR angiography (MRA), and phase contrast angiography MR Venography (PCA-MRV) were obtained. pCASL and SWI sequences were performed using SENSE (sensitivity encoding) parallel imaging techniques. MRI/MRA brain showed no restricted diffusion, abnormal T1/T2/FLAIR signal, arterial occlusion, or irregular angioarchitecture. SWI revealed increased susceptibility along the posterior falx cerebri and right posterior parietal and occipital lobes, and pCASL showed decreased blood flow within these same regions. No falcine sinus was visualized on PCA-MRV, but SWI and pCASL findings led to diagnosis of falcine sinus thrombosis and initiation of appropriate treatment. Repeat MRI one month later showed interval resolution of the abnormal SWI findings and a now patent persistent falcine sinus visualized on PCA-MRV imaging. Routine use of SWI imaging on all brain MRIs and addition of pCASL imaging when there is concern for ischemia or infarction in the emergent setting can limit the risk of missed occult diagnoses like a thrombosed falcine sinus.

A global database of nitrogen and phosphorus excretion rates of aquatic animals.

Animals can be important in modulating ecosystem-level nutrient cycling, although their importance varies greatly among species and ecosystems. Nutrient cycling rates of individual animals represent valuable data for testing the predictions of important frameworks such as the Metabolic Theory of Ecology (MTE) and ecological stoichiometry (ES). They also represent an important set of functional traits that may reflect both environmental and phylogenetic influences. Over the past two decades, studies of animal-mediated nutrient cycling have increased dramatically, especially in aquatic ecosystems. Here we present a global compilation of aquatic animal nutrient excretion rates. The dataset includes 10,534 observations from freshwater and marine animals of N and/or P excretion rates. These observations represent 491 species, including most aquatic phyla. Coverage varies greatly among phyla and other taxonomic levels. The dataset includes information on animal body size, ambient temperature, taxonomic affiliations, and animal body N:P. This data set was used to test predictions of MTE and ES, as described in Vanni and McIntyre (2016; Ecology DOI: 10.1002/ecy.1582).