Application of an augmented reality tool for maxillary positioning in orthognathic surgery – A feasibility study

BACKGROUND: An augmented reality tool for computer assisted surgery named X-Scope allows visual tracking of real anatomical structures in superposition with volume rendered CT or MRI scans and thus can be used for navigated translocation of bony segments. METHODS: In a feasibility study X-Scope was used in orthognathic surgery to control the translocation of the maxilla after Le Fort I osteotomy within a bimaxillary procedure. The situation achieved was compared with the pre-operative situation by means of cephalometric analysis on lateral and frontal cephalograms. RESULTS: The technique was successfully utilized in 5 patients. Maxillary positioning using X-Scope was accomplished accurately within a range of 1mm. The tool was used in all cases in addition to the usual intra-operative splints. A stand-alone application without conventional control does not yet seem reasonable. CONCLUSION: Augmented reality tools like X-Scope may be helpful for controlling maxillary translocation in orthognathic surgery. The application to other interventions in cranio-maxillofacial surgery such as Le Fort III osteotomy, fronto-orbital advancement, and cranial vault reshaping or repair may also be considered.     

Nurses' Logs as an Evaluation Tool for School-Based Violence Prevention Programs

ABSTRACT: Programs for preventing violence among youth should be evaluated to determine if they are effective. Nurses' logs appear to be a useful tool for evaluating school-based violence prevention programs. The logs provide a record of students' visits to the school nurse that can be used to determine if a violence prevention program is associated with a reduction in fighting—and other injury-related nurse visits. This method has many strengths: it is simple and inexpensive, it does not interrupt the school routine, it permits school-level rather than student-level data collection, it provides a ready "baseline," and it allows continuous data collection. However, potential limitations do exist. For example, the method may provide insufficient information and may be affected by factors unrelated to the intervention. School officials can increase the usefulness of the logs by encouraging standardization and providing training in their use.     

Fucose and fucosyllactose enhance in-vitro hippocampal long-term potentiation

Bath application of -fucose and -fucosyllactose ( F1 increases the potentiation of the population spike amplitude (POP-spike) and the field excitatory postsynaptic potential (fEPSP) after tetanization of the Schaffer collaterals of the rat hippocampus. The ineffective isomers -fucose and 3-fucosyllactose (3-F1) have no such effect. Since not only the maintenance of long-term potentiation LTP is influenced but also its induction is drastically improved, an effect of the sugars via the formation of glycoproteins but also via different actions on induction mechanisms is discussed.     

Der Nachweis des frischen Herzinfarktes beim Menschen durch Bestimmung der Wasserstoffionenkonzentration im Herzmuskel mit Indicatorpapier

Zusammenfassung Bei 3 Patienten, die unmittelbar nach herzchirurgischen Eingriffen verstarben, konnte durch Bestimmung der Wasserstoffionenkonzentration [H⁺] mit Indicatorpapier am Gefrierschnitt des Herzens 1–2 Std nach dem Tod jeweils eine umschriebene ischämische Schädigung nachgewiesen und das Alter des frischen Herzinfarktes anhand der veränderten [H⁺] festgestellt werden. Innerhalb der ersten 1–2 Std nach Beginn der Herzmuskelischämie war die [H⁺] in dem ischämisch geschädigten Bereich erhöht (pH<6.0). Anschließend wies der Infarktbereich, im Randbereich beginnend, eine erniedrigte Wasserstoffionenkonzentration (pH 7.4–7.5) auf.Im Zusammenhang mit der erniedrigten [H⁺] ließ sich mit der Perjodsäure Schiff-(PAS-) Reaktion sogenanntes PAS-positives diastaseresistentes Material im Myokard nachweisen. Beim enzymhistochemischen Succinodehydrogenasenachweis fand sich in einem 7–8 Std alten Infarkt eine verstärkte Enzymreaktion.

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The demonstration of acute human cardiac infarction by determining the hydrogen ion concentration of the myocardium with indicator paper

Summary In three patients who died immediately after surgical procedures on the heart it was possible one—two hours after death to demonstrate with indicator paper on frozen sections of myocardium a circumscribed ischemic lesion and to determine the age of the infarction from the changed hydrogen ion concentration. Within the first one—two hours after the onset of ischemia the hydrogen ion concentration in the area of ischemic damage is increased (pH<6.0). Subsequently the infarcted area, beginning in the border zone, shows a decreased hydrogen ion concentration (pH appr. 7.4–7.5).As to the decreased hydrogen ion concentration, it was possible with the periodic-acid-Schiff (PAS) reaction to demonstrate so-called PAS-positive diastase-resistant material in the myocardium. The enzymhistochemical succinodehydrogenase test showed an increased enzyme reaction in an infarction which was 7–8 hours old.

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Mit Unterstützung der Deutschen Forschungsgemeinschaft.

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Vorgetragen auf der Thoraxchirurgischen Arbeitstagung, Februar 1970 in Bad Nauheim.     

Anterior segment evaluation of infants with retinopathy of prematurity

To understand the mechanisms of glaucoma in retinopathy of prematurity (ROP), anterior segment evaluation is essential. The authors prospectively examined the anterior segment of 27 eyes of 17 premature infants with stages IV and V ROP. Twenty-six eyes received no previous surgery or treatment. Schi?tz and applanation tonometry were performed. Structural evaluation of each anterior segment was conducted by biomicroscopy and Koeppe gonioscopy. In the 26 eyes, angle closure of greater than 180 degrees was noted in 3 (12%). The authors noted prominent Schwalbe's line in 4 eyes (15%), high iris convexity in 15 (58%), hypopigmentation of the iris root in 19 (73%), translucent matrix in the angles ("Barkan's-type" membrane) in 18 (69%), posterior synechiae in 16 (62%), visible iris or angle vessels in 12 (46%), and pigment clumping in the angle recess in 12 (46%). This study identified structural abnormalities in the anterior segment of ROP infants, including pathologic changes and anatomic features that could have a developmental origin.