A Morphometric Analysis for the Feasibility of Percutaneous Translacerum Access of the Internal Carotid Artery Based on Computed Tomography Angiography.

BACKGROUND: The increasing frequency of elderly patients with severe tortuous anatomy, especially when combined with fibromuscular dysplasia, can make intracranial canalization severely difficult or impossible. Computed tomography angiography was used to determine the feasibility of accessing the internal carotid artery (ICA) via a percutaneous translacerum approach. METHODS: Twenty consecutive stroke activations with CT angiography were reconstructed in three-dimensional models to take measurements to assess if currently available technologies could safely provide access. We assessed the diameter of the foramen lacerum and ICA. Entry points and angulations were measured based on trajectory. Our trajectory was based on anatomic observations that provided a safe corridor from the angle of the jaw to the foramen lacerum. RESULTS: Based on the 40 carotid arteries from 20 patients, 77.5% had a large enough foramen lacerum to provide access to the ICA. Although there were no traversals of the pharynx, we noted a 20% traversal of the eustachian tube and 5% traversal of a small maxillary artery branch. There was no large-vessel traversal by the trajectory. All patients with bilateral stenotic foramen lacerum were African-American women; 44% of African-American women had bilateral stenotic foramen lacerum. The diameter of the ICA and foramen lacerum would not be prohibitive of sheath placement in patients without stenosis with adequate canalized length of sheath necessary for stability. CONCLUSIONS: Access of the ICA via the foramen lacerum can be safely performed with currently available technologies.

Comparison of modern techniques for saliva screening.

Saliva stains present a unique challenge in the forensic setting, often challenging the analyst to weigh the value of presumptive indication of the fluid versus the potential for DNA analysis to yield identification information. There are many situations in which determining the presence of a body fluid is probative and further corroborates DNA evidence. That said, even a minute portion of sample consumed by a screening test could mean the difference between a full, partial, or null profile obtained through DNA analysis. The basis of presumptive testing or screening of saliva has historically been based on the presence of amylase, a component found in relatively high concentrations in human saliva versus other body fluids and substances. Though the current available methods for the screening of saliva in a forensic application have grown in number, the popularity of these methods seemingly has not. This study attempts to identify a specific and sensitive saliva screening test by comparing three modern techniques--the recently released SALIgAE, Phadebas, and starch-iodine mini-centrifuge test--on the basis of sensitivity, specificity, mixtures, and simulated casework samples while also considering sample consumption. The Phadebas method for presumptive saliva testing detected dilutions of neat saliva down to 1:200 versus considerably less sensitive results with SALIgAE and the starch-iodine mini-centrifuge test. Utilizing a screening test with a high degree of sensitivity, such as Phadebas, allows an analyst to gain a maximum amount of information in the form of body fluid indication and DNA results because of the consumption of a small portion of sample.