IMAGING OF INTRACRANIAL SPACE OCCUPYING LESIONS

Introduction: With advanced MRI techniques such as perfusion, diffusion, and spectroscopy, it is now possible to differentiate between various intracranial lesions. Materials and Methods: This prospective cohort study was conducted on 50 patients referred by various clinical departments with clinical suspicion of intracranial space occupying lesions, evaluated by computed tomography & magnetic resonance imaging. Result: Solitary lesions were present in 35 patients (70%) & multiple lesions in 15 patients (30%). 68.00% lesions were Supratentorial & 32.00% infratentorial in location. Most common supratentorial location in adults was frontal lobe 40% followed by parietal lobe 30%. Most common supratentorial locations in children were frontal lobe. Infratentorially, cerebellum & posterior fossa were found to be most common location in adults & children respectively. Supratentorial lesions were most common both in adults & children. 60% lesions were intraaxial & 40 % extra axial in location. In adults, intraaxial lesions were more common than in children. Conclusion: Intracranial space occupying lesions comprise of a diverse group of lesions. With the introduction of CT & MRI scanning, imaging of lesions has acquired a new dimension whereby excellent anatomical detail in axial, sagittal & coronal planes as well as lesion characterization has become possible. Key words: Brain, CT, MRIs

Preservation of nautilid soft parts inside and outside the conch interpreted as central nervous system, eyes, and renal concrements from the Lebanese Cenomanian

Nautilid, coleoid and ammonite cephalopods preserving jaws and soft tissue remains are moderately common in the extremely fossiliferous Konservat-Lagerstätte of the Hadjoula, Haqel and Sahel Aalma region, Lebanon. We assume that hundreds of cephalopod fossils from this region with soft-tissues lie in collections worldwide. Here, we describe two specimens of Syrionautilus libanoticus (Cymatoceratidae, Nautilida, Cephalopoda) from the Cenomanian of Hadjoula. Both specimens preserve soft parts, but only one shows an imprint of the conch. The specimen without conch displays a lot of anatomical detail. We homologise the fossilised structures as remains of the digestive tract, the central nervous system, the eyes, and the mantle. Small phosphatic structures in the middle of the body chamber of the specimen with conch are tentatively interpreted as renal concrements (uroliths). The absence of any trace of arms and the hood of the specimen lacking its conch is tentatively interpreted as an indication that this is another leftover fall (pabulite), where a predator lost parts of its prey. Other interpretations such as incomplete scavenging are also conceivable.

Fossilized leftover falls as sources of palaeoecological data: a ‘pabulite’ comprising a crustacean, a belemnite and a vertebrate from the Early Jurassic Posidonia Shale

Especially in Lagerstätten with exceptionally preserved fossils, we can sometimes recognize fossilized remains of meals of animals. We suggest the term leftover fall for the event and the term pabulite for the fossilized meal when it never entered the digestive tract (difference to regurgitalites). Usually, pabulites are incomplete organismal remains and show traces of the predation. Pabulites have a great potential to inform about predation as well as anatomical detail, which is invisible otherwise. Here, we document a pabulite comprising the belemnite Passaloteuthis laevigata from the Toarcian of the Holzmaden region. Most of its soft parts are missing while the arm crown is one of the best preserved that is known. Its arms embrace an exuvia of a crustacean. We suggest that the belemnite represents the remnant of the food of a predatory fish such as the shark Hybodus.

Incidence and Radiological Findings of Incidental Sinus Opacifications in Patients Undergoing Septoplasty or Septorhinoplasty

Objectives: Although the routine use of computed tomography (CT) is controversial, it is employed in the preoperative screening of patients undergoing septoplasty or septorhinoplasty. The aim of this study was to evaluate the incidence and radiological characteristics of incidentally found sinus pathologies on screening CT in patients who underwent elective septoplasty or septorhinoplasty. Methods: We retrospectively reviewed the patients who underwent septoplasty and septorhinoplasty performed by a single surgeon (Y.J.J.) at Asan Medical Center between January 2016 and December 2017. CT images of 372 patients who had agreed to undergo preoperative CT were reviewed to determine the location and extent of incidental sinus opacifications. Results: Of the 372 patients, 107 (28.8%) showed incidental sinus lesions on CT images. Opacifications were mainly found in the maxillary sinus (73, 68.2%), followed by the ethmoid (34, 31.8%), sphenoid (10, 9.3%), and frontal (3, 2.8%) sinuses. The most common sinus lesion was retention cyst (55, 51.4%), and the second most common one was opacification and mucosal thickening (46, 43%). Other lesions such as osteoma (3, 2.8%), dental cyst (2, 1.9%), and mucocele (1, 0.9%) were rarely found. Conclusions: In patients undergoing septoplasty or septorhinoplasty, the incidence of incidental sinus lesions was approximately 28.8% (107/372). This results indicate that preoperative CT in patients undergoing septoplasty or septorhinoplasty might be helpful to surgeons not only for better understanding the anatomical detail but also for detecting hidden paranasal sinus disease.

Detailed analysis of chick optic fissure closure reveals Netrin-1 as an essential mediator of epithelial fusion

Epithelial fusion underlies many vital organogenic processes during embryogenesis. Disruptions to these cause a significant number of human birth defects, including ocular coloboma. We provide robust spatial-temporal staging and unique anatomical detail of optic fissure closure (OFC) in the embryonic chick, including evidence for roles of apoptosis and epithelial remodelling. We performed complementary transcriptomic profiling and show that Netrin-1 (NTN1) is precisely expressed in the chick fissure margin during fusion but is immediately downregulated after fusion. We further provide a combination of protein localisation and phenotypic evidence in chick, humans, mice and zebrafish that Netrin-1 has an evolutionarily conserved and essential requirement for OFC, and is likely to have an important role in palate fusion. Our data suggest that NTN1 is a strong candidate locus for human coloboma and other multi-system developmental fusion defects, and show that chick OFC is a powerful model for epithelial fusion research.

Drawing as transcription: how do graphical techniques inform interaction analysis?

Drawing as a form of analytical inscription can provide researchers with highly flexible methods for exploring embodied interaction. Graphical techniques can combine spatial layouts, trajectories of action and anatomical detail, as well as rich descriptions of movement and temporal effects. This paper introduces some of the possibilities and challenges of adapting graphical techniques from life drawing and still life for interaction research. We demonstrate how many of these techniques are used in interaction research by illustrating the postural configurations and movements of participants in a ballet class. We then discuss a prototype software tool that is being developed to support interaction analysis specifically in the context of a collaborative data analysis session.

Drawing as transcription: how do graphical techniques inform interaction analysis?

Drawing as a form of analytical inscription can provide researchers with highly flexible methods for exploring embodied interaction. Graphical techniques can combine spatial layouts, trajectories of action and anatomical detail, as well as rich descriptions of movement and temporal effects. This paper introduces some of the possibilities and challenges of adapting graphical techniques from life drawing and still life for interaction research. We demonstrate how many of these techniques are used in interaction research by illustrating the postural configurations and movements of participants in a ballet class. We then discuss a prototype software tool that is being developed to support interaction analysis specifically in the context of a collaborative data analysis session.

Drawing as transcription: how do graphical techniques inform interaction analysis?

Drawing as a form of analytical inscription can provide researchers with highly flexible methods for exploring embodied interaction. Graphical techniques can combine spatial layouts, trajectories of action and anatomical detail, as well as rich descriptions of movement and temporal effects. This paper introduces some of the possibilities and challenges of adapting graphical techniques from life drawing and still life for interaction research. We demonstrate how many of these techniques are used in interaction research by illustrating the postural configurations and movements of participants in a ballet class. We then discuss a prototype software tool that is being developed to support interaction analysis specifically in the context of a collaborative data analysis session.

Detailed analysis of chick optic fissure closure reveals Netrin-1 as an essential and conserved mediator of epithelial fusion during vertebrate embryogenesis

ABSTRACTEpithelial fusion underlies many vital organogenic processes during embryogenesis. Disruptions to these cause a significant number of human birth defects, including ocular coloboma. We provide robust spatial-temporal staging and unique anatomical detail of optic fissure closure (OFC) in the embryonic chick, including strong evidence for roles of apoptosis and epithelial remodelling. We performed complementary transcriptomic profiling and show that Netrin-1 (NTN1) is precisely expressed in the chick fissure margin at the fusion plate but is immediately downregulated after fusion. We further provide a combination of protein localisation and phenotypic evidence in chick, humans, mice and fish that Netrin-1 has an evolutionarily conserved and essential requirement for OFC, and is likely to have a major role in palate fusion. Our data reveal that NTN1 is a new locus for human coloboma and other multi-system developmental fusion defects, and that chick OFC is a powerful model for epithelial fusion research.