Decellularization of Porcine and Primate Optic Nerve Lamina

The optic nerve lamina cribrosa is a mesh-like collagenous structure consisting of an extracellular matrix with varying porosity and glial cell distribution through which axons of retinal ganglion cells travel en route to the lateral geniculate nucleus. There has been significant interest in its structure with respect to its possible role in the pathophysiology of glaucomatous optic neuropathy. Our goal was to decellularize porcine and primate lamina to evaluate for a potential role as a three-dimensional scaffold for stem cell growth, regeneration, and delivery

Reconstruction Of An Outer Retina Using Electrospun Polycaprolactone (pcl) And Cells Derived From Human Embryonic Stem Cells.

As a step towards engineering an outer retina suitable for transplantation, we designed a biocompatible, biodegradable scaffold that allows retinal progenitor cells (RPCs) to form flat, laminar structures. The scaffold minimizes the exposure of retinal progenitors to extracellular matrix components that are not found in the retina, and enables co-culture with the retinal pigment epithelium. Scaffolds were formed from electrospun fibers of polycaprolactone (PCL). Scaffold thickness was varied by increasing the duration of collection during electrospinning; porosity and pore size distribution was adjusted by varying polymer concentration in solution. The porosity and thickness of the sheets were varied to optimize cell to cell contact formation and PCL degradation rate, respectively. RPCs derived from human embryonic stem cells (hESC-derived RPCs) were cultured to form neurospheres. Dissociated neurospheres were seeded onto +/- laminin coated PCL sheets in normal or low O2 incubators, and maintained in two types of serum free medium. Fluorescence labeling and confocal microscopy were used to assess tissue morphology. Individual PCL fibers were ~3 ìm thick, sheets varied from 20-200 ìm in thickness, and pores ranged from 5-100 ìm in diameter. The scaffolds degraded over 4-7 weeks. Scaffolds with pores 25-50 ìm in diameter were subsequently chosen for culture experiments. Biomechanical strength testing estimated a Young\u27s modulus of 0.071 megapascals (MPa). Confocal imaging confirmed that the RPCs penetrated the thickness of the scaffold irrespective of laminin coating and O2 level, and continued to express retinal markers such as Pax6, recoverin, and N-cadherin, with heightened expression in the differentiation medium. Cells adhered uniformly to laminin-coated PCL, but formed aggregates on uncoated PCL. Staining for the proliferative marker, Ki67, indicated active cell division in both medium types and O2 levels. Preliminary RPE: RPC co-culture experiments with laminin coated PCL in low oxygen conditions revealed polarization of N-cadherin, with concomitant stress fiber formation in the RPE monolayer. Overall, electrospun PCL polymers sustained the differentiated properties acquired by neurospheres and appear to be suitable scaffolds for reconstructing an outer retinal layer

Orbit Case #1 - That Looks Foreign to Me

This symposium has been created to highlight the surgical aspects of our field and to educate neuroophthalmologists and trainees through the presentation and discussion of complex surgical neuroophthalmic case scenarios

The Sound of Hoofbeats (slideshow)

A 42-year-old woman with a recurrent cerebral malignant glioma in the left frontal lobe on clinical trial presented with blurry vision in her right eye 6 days after undergoing sinus surgery for paranasal inflammatory changes. She presented approximately 1 month after the sixth cycle of systemic steroids, Durvalumab (PD-L1 inhibitor), and Bevacizumab.Patient Care, Medical Knowledge, PBLI, SBP, Professionalism, IPCS, VBintracranialtumor

The Sound of Hoofbeats (abstract)

A 42-year-old woman with a recurrent cerebral malignant glioma in the left frontal lobe on clinical trial presented with blurry vision in her right eye 6 days after undergoing sinus surgery for paranasal inflammatory changes. She presented approximately 1 month after the sixth cycle of systemic steroids, Durvalumab (PD-L1 inhibitor), and Bevacizumab.Patient Care, Medical Knowledge, PBLI, SBP, Professionalism, IPCS, VBintracranialtumor

Malignant solitary fibrous tumor of the orbit: Spectrum of histologic features

Purpose: Primary malignant solitary fibrous tumor (SFT) of the orbit is a rare spindle cell neoplasm that requires excisional biopsy for histopathological diagnosis. We present a clinical case using contemporary immunohistochemical stains, report on the latest World Health Organization classification, and provide a review of the literature. Observations: Report of a single case of a 65 year old male who presented with right-sided proptosis, limited adduction, ptosis, lateral globe displacement, and cheek festooning. Neuroimaging revealed a 2.2 cm, extraconal heterogeneous mass that diffusely enhanced. En-bloc tumor resection confirmed SFT malignancy based upon nuclear atypia, hypercellularity, and increased mitotic activity (13 mitotic figures/10 high powered fields). Ki-67 showed 2% nuclear staining in the benign tumor and 10–15% staining in the malignant counterpart. Immunohistochemical analysis revealed diffuse Stat6 positivity, CD 34 positivity with partial lack of staining within the malignant portion, S-100 positivity in the malignant portion, and overall negativity for CAM 5.2, desmin, actin, CD 31, and CD 117. Conclusions and importance: Immunoprofiling is helpful to making the diagnosis of malignant solitary fibrous tumor of the orbit. Complete tumor resection continues to be the preferred treatment. The behavior of extrathoracic SFT is unpredictable, and patients with SFT in all locations require careful, long-term follow-up

Colorectal carcinoma presenting in the orbit: mass effect from an uncommon cause.

An 84-year-old male with previously documented poor medical follow-up presented with progressive painless proptosis of the right eye. Right upper eyelid ptosis, limited motility, proptosis, and inferomedial displacement of the right globe were noted on the exam. Computed tomography (CT) imaging revealed a right retrobulbar extraconal heterogenous mass with ill-defined borders. Biopsy revealed a malignant adenocarcinoma with tumor markers suggestive of a colorectal primary. A rectal mass was identified during a systemic workup. After biopsy, the patient was diagnosed with stage IV metastatic rectal adenocarcinoma. He began palliative radiation therapy shortly following diagnosis