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Significant progress has been made in artificial intelligence and computer vision research in recent years. Machine learning methods excel in a wide variety of tasks where sufficient data are available. We describe the application of a deep convolutional neural network for the prediction of treatment indication with anti-vascular endothelial growth factor (VEGF) medications based on central retinal optical coherence tomography (OCT) scans. The neural network classifier was trained with OCT images acquired during routine treatment at the University of Regensburg over the years 2008-2016. In over 95% of the cases the treatment indication was accurately predicted based on a singular OCT B scan without human intervention. Despite promising classification the results of deep learning techniques, should always be controlled by the treating physician because false classification can never be excluded due to the probabilistic nature of the method.

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Gas tamponades are widely used during intraocular surgery. The high surface tension at the intraocular liquid to gas interface is used in retinal detachment and macular surgery, as well as in lamellar corneal transplant surgery. The patient's postoperative posture determines the position of the gas bubble inside the eye. The article describes the development, physical laws and methods for postoperative positioning after intraocular surgery.

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Polypoidal choroidal vasculopathy (PCV) is a disease that was first described almost 30 years ago. The disease is characterised by alterations of the posterior pole such as serous or serosanguineous detachments of the retina or the retinal pigment epithelium (RPE) around the optic nerve or in the central macula. The optimal therapeutic regime remains unclear. There are several studies suggesting that patients who do not respond satisfactorily to intravitreal anti-VEGF treatment are suffering from PCV which can be detected by indocyanine green angiography. Alternative therapeutic options consist of photodynamic therapy or laser photocoagulation for extrafoveal lesions.

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Senile scleral plaques are characterized by a calcification located at the insertion of the horizontal rectus muscles. As a possible cause for their development a combination of solar tissue damage and continuous mechanical stress is discussed. We present a case of a 76-year-old male whose wife noticed expulsion of a calcified scleral plaque while applying antiglaucoma eyedrops. The local antiglaucoma therapy was stopped and acetacolamide was administered. Local therapy consisted of hyaluronic acid eyedrop and calcium pantothenate and retinol palmiate eye ointment. This treatment led to a rapid reepithelialization. The expulsion of calcified senile scleral plaques is a described complication which can necessitate surgical treatment.

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Systemic lupus erythematosus (SLE) is a chronic, relapsing and remitting autoimmune disease of unknown etiology. As in other rheumatic diseases sicca syndrome is often present. Additionally retinal vascular pathologies such as cotton wool spots and intraretinal hemorrhages are present in 7-8% of patients with SLE. SLE-related retinal vascular pathologies are activity markers and a prognostic factor for poor outcome. The case of a 38-year-old patient is reported with decompensated SLE who presented in our clinic with floaters and flickering scotoma but good visual acuity. Funduscopy and fluorescence angiography revealed bilateral choroidal vessel occlusions. Additionally, a hemorrhagic choroidal infarction and a preretinal hemorrhage were detected in the right eye. In summary SLE can result in choroidal vasoocclusion especially if decompensated arterial hypertension is present.

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The purpose of this study was to assess the use of a novel bone void filler consisting of Type I collagen and various growth factors (VEGF, TGFß-1, TGFß-2, IGF-1, BMP-2, BMP-3, and BMP-7) and surgical fixation to treat diaphyseal forearm pseudarthroses. Eleven patients underwent an osteosynthesis procedure for isolated pseudarthrosis fractures of the forearm (six radial and five ulnar diaphysis). The mean duration between the initial failed surgical fixation and re-operation was 38 weeks. Radiographic signs of fracture healing after the application of the bone void filler were noted at a mean of 5 weeks, and complete fracture consolidation was achieved at a mean of 6 weeks. All patients demonstrated improved range of motion and grip strength. Additionally, all patients were pain-free by 6 weeks. The combination of a novel bovine bone-derived bone void filler and stable internal fixation led to union and rapid healing of forearm pseudarthroses.

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BACKGROUND: The novel protein PTPIP51 (SwissProt accession code Q96SD6) is known to interact with two non-transmembrane protein-tyrosine phosphatases, PTP1B and TCPTP in vitro. Overexpression of the full-length protein induces apoptosis in HeLa and HEK293T cells (Lv et al. 2006). PTPIP51 shows a tissue-specific expression pattern and is associated with cellular differentiation and apoptosis in some mammalian tissues, especially in human follicular and interfollicular epidermis. PTPIP51 protein is expressed in all suprabasal layers of normal epidermis, whereas the basal layer contains PTPIP51 mRNA only but lacks the protein. OBJECTIVES: The expression of PTPIP51 was investigated in keratinocyte carcinomas, that is human basal cell carcinomas (BCCs) and squamous cell carcinomas (SCCs) as well as Bowen's disease (BD) and keratoacanthomas (KAs) on a transcriptional (mRNA) and translational (immunohistochemical) level. METHODS: Formalin-fixed, paraffin-embedded sections of BCCs, SCCs, KAs and BD, respectively, were analysed by RT-PCR, as well as immunohistochemistry and subsequent fluorescence microscopy. PTPIP51-positive cells of the tumour and the surrounding stroma were identified on the basis of specific morphological features by means of H & E staining. To obtain further information about a putative function of PTPIP51, a possible association of PTPIP51 with apoptotic cells, as well as an assumed negative correlation with proliferating cells was investigated by means of an in-situ TUNEL assay and Ki67/MIB-1 antigen staining, respectively. Co-immunostainings with PTPIP51 were performed for the following antigens: TCPTP, PTP1B and beta-catenin. RESULTS: PTPIP51-expression was detected in BCCs and SCCs of the skin, as well as in KAs and BD. Both types of keratinocyte carcinoma revealed a specific localization pattern of PTPIP51 in malignant keratinocytes. Whereas PTPIP51-positive cells of BCC were found to form two cluster types with a different subcellular localization of the protein, i.e. cytoplasmic and nuclear or predominantly membranous, investigation of SCC revealed a meshwork-like appearance of PTPIP51-positive malignant keratinocytes, created by a mainly membranous localization. BD and KA resembled the findings of PTPIP51-expression in SCC. Furthermore, we observed a partial co-localization of PTP1B and PTPIP51 in BCC. SCC and BCC showed a co-expression and partial co-localization of PTPIP51 with beta-catenin. Some PTPIP51-positive cells were found to undergo apoptosis. PTPIP51 was also expressed in cells comprising the surrounding stromal microenvironment. This was particularly noticed for endothelial cells lining peritumoural vessels as well as for infiltrating cells of both, the innate and the adaptive immune system. CONCLUSIONS: The results showed a distinct mainly membranous expression pattern of PTPIP51 in BCCs and SCCs. Since PTPIP51 was also detected in the peritumoural tissue, the protein may play a crucial role in ke

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Osteonecrosis of the femoral head is a disease of the young patient which eventually destroys the hip joint. In the early stage of the disease, treatment options are aimed at preserving the femoral head. Unfortunately, many patients present with late-stage disease (Ficat III and IV).In late-stage disease the treatment of choice is total hip arthroplasty. The high failure rate of total hip arthroplasty in young patients with osteonecrosis of the femoral head, however, made it an unfavourable treatment option. The results of hemiresurfacing (femoral resurfacing) in this patient population have been very disappointing due to high revision rates and insufficient pain relief. More recently, promising short- and mid-term results were reported with the use of total resurfacing with a survivorship of 90-93% after 3.4-10 years. Our own results in 60 patients show an overall survivorship of 92% after a mean follow-up of 4.8 years (1.6-6.5 years). Total hip resurfacing is a valuable treatment option for late-stage osteonecrosis based on recent study results.

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Space-based inflatable technology is of current interest to NASA and DOD, and in particular to the Air Force and Phillips Laboratory. Potentially large gains in lowering launch costs, through reductions in structure mass and volume, are driving this activity. Diverse groups are researching and developing this technology for radio and radar antennae, optical telescopes, and solar power and propulsion applications. Regardless of the use, one common requirement for successful application is the accuracy of the inflated surface shape. The work reported here concerns the shape control of an inflated thin circular disk through use of a nonlinear finite element analysis. First, a review of the important associated Hencky problem is given. Then we discuss a shape modification, achieved through enforced boundary displacements, which resulted in moving the inflated shape towards a desired parabolic profile. Minimization of the figure error is discussed and conclusions are drawn.