Cranial Nerve Foramina Part I: A Review of the Anatomy and Pathology of Cranial Nerve Foramina of the Anterior and Middle Fossa.

Cranial nerve foramina are integral exits from the confines of the skull. Despite their significance in cranial nerve pathologies, there has been no comprehensive anatomical review of these structures. Owing to the extensive nature of this topic, Part I of our review, presented here, focuses on the foramina of the anterior and middle cranial fossae, discussing each foramen's shape, orientation, size, surrounding structures, and structures that traverse them. Furthermore, by comparing the size of each foramen against the cross-sectional areas of its contents, we estimate the amount of free space in each. We also review lesions that can obstruct the foramina and discuss their clinical consequences.

Cranial Nerve Foramina: Part II - A Review of the Anatomy and Pathology of Cranial Nerve Foramina of the Posterior Cranial Fossa.

Cranial nerve foramina are integral exits from the confines of the skull. Despite their significance in cranial nerve pathologies, there has been no comprehensive anatomical review of these structures. Owing to the extensive nature of this topic we have divided our review into two parts; Part II, presented here, focuses on the foramina of the posterior cranial fossa and discusses each foramen's shape, orientation, size, surrounding structures, and structures that pass through it. Furthermore, by comparing foramen sizes against the cross-sectional areas of their contents, we determine the amount of free space available within each. We also review lesions that can obstruct each foramen and discuss the clinical consequences.

More Than Meets the Eye: The Contributions of John Dalrymple (1803-1852).

Having authored two major ophthalmology textbooks and honored with the eponym, the "Dalrymple sign," many are familiar with the works of Dr. John Dalrymple when it comes to the eye. However, few are aware of his other, numerous and wide-ranging contributions to the fields of science and medicine. In this article, we discuss the life and work of a man dedicated to the pursuit and advancement of knowledge and education.

Hiding Within the Cracks: Case Report of Rare Sutural Bone Found at the Nasion.

Pathology such as skull fractures can be misdiagnosed in the presence of anatomical variations. One variant that has had little description in the literature are the sutural bones associated with the nasal bones. Herein, we describe a case of a rare sutural bone at the nasion, between the bones of the right nasal, frontal, and maxillary frontal process. To our knowledge, this is the first report of such a variant bone in this location, and such it should be considered by clinicians when evaluating patients for pathology in this region.

Orbital Blowout Fracture with Complete Dislocation of the Globe into the Maxillary Sinus.

This rare case report describes the diagnosis and treatment of an isolated left-sided orbital floor fracture with a complete dislocation of the globe into the maxillary sinus and briefly discusses the indications of surgery and recovery for orbital floor fractures in general. Complete herniation of the globe through an orbital blow-out fracture is uncommon. However, the current case illustrates that such an occurrence should be in the differential diagnosis and should be considered, especially following high speed/impact injuries involving a foreign object. In these rare cases, surgical intervention is required.

A Rare Case of Double-Headed Psoas Minor Muscle with Review of its Known Variants.

Variations of the muscles of humans are important to remember for those who interpret imaging and for those who operate near these anomalies. Herein, we describe a rare two-headed psoas minor muscle found incidentally during dissection of the posterior abdominal wall. This case is presented with a detailed review of all known variations of the minor psoas and is analyzed through a literature review.

Intracranial Anatomical Triangles: A Comprehensive Illustrated Review.

There are multiple anatomical triangles of the skull base. However, to our knowledge, there has been no comprehensive review of these geometric landmarks. To allow for a safe and consistent approach to lesions of the skull base such as those near the internal carotid artery, internal acoustic meatus, and cavernous sinus, a comprehensive review of the variations with illustrations is required. This article provides an overview of the anatomical borders, dimensions, and surgical implications as well as illustrations of the major skull base triangles.

Higher-order looping and nuclear organization of Tcra facilitate targeted rag cleavage and regulated rearrangement in recombination centers.

V(D)J recombination is essential for generating a diverse array of B and T cell receptors that can recognize and combat foreign antigens. As with any recombination event, tight control is essential to prevent the occurrence of genetic anomalies that drive cellular transformation. One important aspect of regulation is directed targeting of the RAG recombinase. Indeed, RAG accumulates at the 3' end of individual antigen receptor loci poised for rearrangement; however, it is not known whether focal binding is involved in regulating cleavage, and what mechanisms lead to enrichment of RAG in this region. Here, we show that monoallelic looping out of the 3' end of the T cell receptor α (Tcra) locus, coupled with transcription and increased chromatin/nuclear accessibility, is linked to focal RAG binding and ATM-mediated regulation of monoallelic cleavage on looped-out 3' regions. Our data identify higher-order loop formation as a key determinant of directed RAG targeting and the maintenance of genome stability.