Live outflow imaging in porcine eyes

Purpose: Although outflow of aqueous humor can be estimated using fluorophotometry and tonography, no method exists to assess segmental outflow directly. This has hindered investigations into outflow resistance elements that are downstream of the trabecular meshwork and into causes of failure of canal-based minimally invasive glaucoma surgeries (MIGS). Here, we describe a method to observe and quantify conventional outflow directly in ex vivo whole eyes and an organotypic culture model using standard fluorescence visualization equipment. Results: Aqueous outflow paths could be distinguished from venous and arterial vessels. Intricate vascular tree filling patterns were observed down to estimated 50 micrometer diameter. Whole eyes demonstrated significantly earlier filling of the nasal (SN, IN) than of the temporal quadrants (ST, IT). The fastest, superonasal quadrant filled 1.6 times faster than the slowest, superotemporal quadrant (p≤0.05). The inferotemporal quadrant also filled faster than the superotemporal quadrant. In contrast, perfused anterior segment cultures had lost these characteristic filling time differences (p>0.05). One eye showed no outflow after 20 minutes of pressurization. After three days of culture, the same quadrant that was the fastest in whole eyes (SN), was 2.2 times as fast as the slowest (ST) but this did not reach statistical significance with the number of eyes tested. The eye without flow at 20 minutes did not recuperate during 3 days of culture. Reverse filling was occasionally seen in d3 anterior segments (bottom row, red arrowhead). Whole eyes could not be reliably cultured for 3 days. Discussion: Canalograms using a green fluorescent chromophore can be obtained with standard visualization equipment to estimate the local outflow function. Regionally different outflow patterns and filling times can be observed that match channel size equivalents in human eyes. Outflow is impaired in fresh anterior segment cultures but then normalizes to the pattern seen in whole eyes. The nasally increased flow may have implications for placement and study of MIGS

Trabecular Meshwork Engineering and Live Tracking in Perfused Porcine Anterior Segments

Purpose: To establish a trabecular meshwork ™ engineering model using porcine anterior segments of consistently high quality in a physiological, fixed perfusion system.\ud \ud Discussion: Compared to previously used human donor eyes, this inexpensive porcine anterior segment perfusion model is of sufficient, repeatable high quality to develop strategies to modify genetically, ablate and repopulate the TM. Despite significant anatomic differences, effects of transduction and ablation in the porcine model presented here replicate key aspects of previously explored human, feline and rodent models

A rolling ball like mass in right atrium of a 6 year old child

Cardiac myxoma is a common tumor occurring more commonly in the left atrium in adult females. Its occurrence in pediatric age group is rare; the more common tumors are rhabdomyoma and fibroma. Presentation of myxoma on the right side is still rarer in this age group. We report a case of a 6-year-old male child who presented with prolonged fever. On examination, there is an extra diastolic sound with mid-diastolic murmur. Echocardiogram is suggestive of a large ball-like polypoidal mass rolling in the right atrium traversing into the right ventricle. The case was immediately operated, and histopathology confirmed the tumor as myxoma. High index of suspicion is required to diagnose the condition to prevent disastrous complications as the presentation is often enigmatic because of vague constitutional findings in most of the cases