Reconstruction of the Exenterated Orbit with an Island Pericranial Flap: A New Surgical Approach

Background: Reconstruction of the bony socket after orbital exenteration is a matter of much debate. Prompt defect closure with a microvascular flap is desirable but involves a major surgical procedure and hence, places considerable burden on the patient. The new surgical technique presented here permits a technically simpler wound closure with fewer complications after orbital exenteration. Methods: Between May 2014 and June 2022 in the ENT department of Regensburg University, nine patients underwent exenteration and reconstruction with a pericranial flap. The flap was raised via a broken line incision in the forehead or endoscopically, incised in a roughly croissant-like shape, then introduced into the orbit through a tunnel in the eyebrow. A retrospective analysis of the patients and considerations about determining the size, shape, and vascular supply of the flap are presented. Results: Flap healing was uncomplicated in all cases. Only 6 weeks after surgery, the flap was stable, making it possible to start adjuvant therapy and prosthetic rehabilitation swiftly. The flap is adapted to the near cone-shape of the orbit. The mean (± standard deviation) surface area of the measured orbits is (39.58 ± 3.32) cm2. The territory of the angular artery provides the periosteal flap arterial blood supply. Venous drainage is via venous networks surrounding the artery. Conclusions: Use of the pericranial flap makes it possible to close the orbital cavity promptly with minimal donor site defect and a short operating time, thereby minimizing the surgical risk and speeding up physical and psychological recovery

Environmental factors shaping the distribution of common wintering waterbirds in a lake ecosystem with developed shoreline

In this study, we tested whether the spatial distribution of waterbirds is influenced by shoreline urbanization or other habitat characteristics. We conducted monthly censuses along shoreline sections of a continental lake (Lake Balaton, Hungary) to assess the abundance of 11 common species that use this lake as a feeding and staging area during migration and winter. We estimated the degree of urbanization of the same shoreline sections and also measured other habitat characteristics (water depth, extent of reed cover, biomass of zebra mussels, distances to waste dumps and to other wetlands). We applied linear models and model averaging to identify habitat variables with high relative importance for predicting bird distributions. Bird abundance and urbanization were strongly related only in one species. Other habitat variables exhibited stronger relationships with bird distribution: (1) diving ducks and coots preferred shoreline sections with high zebra mussel biomass, (2) gulls preferred sites close to waste dumps, and (3) the abundances of several species were higher on shoreline sections close to other wetlands. Our findings suggest that the distribution of waterbirds on Lake Balaton is largely independent of shoreline urbanization and influenced by food availability and connectivity between wetlands

Vascular survey of the maxillary vestibule and gingiva-clinical impact on incision and flap design in periodontal and implant surgeries.

OBJECTIVES Currently, empirical clinical findings on the blood supply of the maxillary vestibule are not backed up with sufficient literature. The purpose of this study was to investigate the mucosal and periosteal vascular supply in the maxillary vestibule macroscopically and radiographically to improve surgical strategies and flap designs. MATERIALS AND METHODS Thirty head corpses were selected (9 dentate, 11 partially edentulous, 10 edentulous). Twenty-six corpses were injected by red latex milk and embalmed with Thiel solution. Four cadavers were prepared for corrosion casting. Arterial path and anastomoses in the maxillary vestibule of dentate, partially edentulous and edentulous ridges, were analyzed macroscopically and by computed tomography (CT). RESULTS Transverse periosteomucosal anastomoses were detected in the posterior and esthetic zones of the maxillary vestibule. The buccal branches penetrated the interdental septum toward the palate. In the esthetic zone, superior labial artery (SLA) supplied the mucosa and the infraorbital artery (IOA) supplied the periosteum. Corrosion casting showed anastomoses between IOA and nasal septal branches. CT analysis revealed ipsilateral and contralateral anastomoses between SLA and IOA. In dentate ridges, mucosal star-shaped terminal branches were detected. CONCLUSIONS The macroscopic and radiographic vascular survey analysis revealed the anatomical background behind several clinically documented phenomena related to oral and periodontal surgeries. CLINICAL RELEVANCE This study permits clinicians to design less invasive flaps when releasing incisions in the maxillary vestibule during periodontal and implant surgeries. Our observations strongly point to the significance of an undamaged periosteum to prevent compromised flap revascularization and wound healing disturbances

The role of fissula ante fenestram in unilateral sudden hearing loss

El objetivo de este trabajo es la modelización del proceso de reconstrucción del sistema inmune de un paciente. El sistema inmune del paciente ha sido eliminado tras recibir radio o químioterapia, a continuación se procede a re- alizar transplante de células blancas. Con el objetivo de modelizar el proceso, se consideran cuatro ecuaciones diferenciales del modelo propuesto en Szymanska [R.4] y una quinta ecuación del modelo propuesto en de Colijn et al [R.2]. Ésta última ecuación contiene seis parámetros desconocidos, para esti- marlos se ha implementado el método de los mínimos cuadrados utilizando un algoritmo de optimización, conocido como Algoritmo de la colonia de hormi- gas (Ant colony Optimization). El método de los mínimos cuadrados se utiliza para hallar una combinación de parámetros que minimice el error cometido entre los datos reales y los obtenidos mediante la simulación numérica. La simulaciones numéricas son obtenidas por el método de Runge-Kutta y se compara con los datos clónicos proporcionados por el Servicio de Inmunología del Hospital La Paz. La optimización de la colonia de hormigas es un método basado en el comportamiento de las hormigas cuando éstas buscan el camino más corto a la fuente de comida.---ABSTRACT---The main goal of this paper is to model the reconstruction process of the immune system of a patient. Due to the chemotherapy, the immune system of the patient has been destroyed; in order to reconstruct it the patient receives a white cells transplant. Having this objective in mind, 4 di erential equations from the Szymanska's model [ R.4 ] and a fth equation from Colijn's model [ R.5 ] have been studied. The latter has 6 unknown parameters, in order to es- timate them the least squares method has been applied using an optimization algorithm known as the ant colony optimization. The least square method has been used to compute a parameter combination that minimize the distance between the real data and the approximated data. The numerical simulations have been obtained through the Runge-Kutta method and are compared to clinical data provided by the Hospital La Paz. The ant colony optimization is a method based on the ant's behavior when they are looking for the shortest path to the food sourc

MRI, CT and high resolution macro-anatomical images with cryosectioning of a Beagle brain: Creating the base of a multimodal imaging atlas.

Most common methods that directly show macro- or microscopic anatomy of the brain usually require the removal of the organ from the neurocranium. However, the brain can be revealed in situ by using proper sectioning techniques. Our aim was to both improve the cryosectioning method, test its limits and create a high-resolution macro-anatomical image series of a Beagle brain, which at the time of the study did not exist. A two-year-old female Beagle has been scanned with CT and MRI ante and post mortem, then the arteries of the head were filled with red resin. After freezing to -80°C, a neurocranium block was created and was embedded into a water-gelatin mix. Using a special milling device and a DSLR camera, 1112 consecutive RGB-color cryosections were made with a 100 μm layer thickness and captured in high resolution (300 dpi, 24-bit color, and pixel size was 19.5 x 19.5 μm). Image post-processing was done with Adobe Photoshop CS3 and Thermo Scientific Amira 6.0 softwares, and as a result of the proper alignment and coregistration, visualization and comparing was possible with all the applied imaging modalities (CT, MRI, cryosectioning) in any arbitrary plane. Surface models from the arteries, veins, brain and skull were also generated after segmentation in the same coordinate system, giving a unique opportunity for comparing the two-dimensional and three-dimensional anatomy. This is the first study which focuses directly to this high-definition multimodal visualization of the canine brain, and it provides the most accurate results compared to previous cryosectioning studies, as using an improved method, higher image quality, more detailed image, proper color fidelity and lower artefact formation were achieved. Based on the methodology we described, it can serve as a base for future multimodal (CT, MR, augmented- or virtual reality) imaging atlases for medical, educational and scientific purposes

Analysis of blood supply in the hard palate and maxillary tuberosity-clinical implications for flap design and soft tissue graft harvesting (a human cadaver study)

OBJECTIVES: The aim of the present study is to provide a detailed macroscopic mapping of the palatal and tuberal blood supply applying anatomical methods and studying specific anastomoses to bridge the gap between basic structural and empirical clinical knowledge. MATERIALS AND METHODS: Ten cadavers (three dentate, seven edentulous) have been prepared for this study in the Department of Anatomy, Semmelweis University, Budapest, Hungary, and in the Department of Anatomy of the Medical University of Graz. All cadavers were fixed with Thiel's solution. For the macroscopic analysis of the blood vessels supplying the palatal mucosa, corrosion casting in four cadavers and latex milk injection in other six cadavers were performed. RESULTS: We recorded major- and secondary branches of the greater palatine artery (GPA) and its relation to the palatine spine, different anastomoses with the nasopalatine artery (NPA), and lesser palatal artery (LPA) as well as with contralateral branches of the GPA. Penetrating intraosseous branches at the premolar-canine area were also detected. In edentulous patients, the GPA developed a curvy pathway in the premolar area. The blood supply around the maxillary tuberosity was also presented. CONCLUSION: The combination of different staining methods has shed light to findings with relevance to palatal blood supply, offering a powerful tool for the design and execution of surgical interventions involving the hard palate. CLINICAL RELEVANCE: The present study provides clinicians with a good basis to understand the anatomical background of palatal and tuberal blood supply. This might enable clinicians to design optimized incision- and flap designs. As a result, the risk of intraoperative bleeding and postoperative wound healing complications related to impaired blood supply can be minimized