A portable widefield fundus camera with high dynamic range imaging capability

Fundus photography is indispensable for clinical detection and management of eye diseases. Limited image contrast and field of view (FOV) are common limitations of conventional fundus cameras, making it difficult to detect subtle abnormalities at the early stages of eye diseases. Further improvements of image contrast and FOV coverage are important to improve early disease detection and reliable treatment assessment. We report here a portable fundus camera, with a wide FOV and high dynamic range (HDR) imaging capabilities. Miniaturized indirect ophthalmoscopy illumination was employed to achieve the portable design for nonmydriatic, widefield fundus photography. Orthogonal polarization control was used to eliminate illumination reflectance artifact. With independent power controls, three fundus images were sequentially acquired and fused to achieve HDR function for local image contrast enhancement. A 101{\deg} eye-angle (67{\deg} visual-angle) snapshot FOV was achieved for nonmydriatic fundus photography. The effective FOV can be readily expanded up to 190{\deg} eye-angle (134{\deg} visual-angle) with the aid of a fixation target, without the need of pharmacologic pupillary dilation. The effectiveness of HDR imaging was validated with both normal healthy and pathologic eyes, compared to a conventional fundus camera.Comment: 12 pages, 8 figure

Bony prominence and variations of the transverse sinus groove: novel anatomical findings in relation to sinus pathologies.

The transverse sinus (TS) is often involved with pathology for structural reasons. The aim of this study was to improve understanding of the anatomy along the groove of the TS and sigmoid sinus (SS), to discuss the relationship between the bony features and pathologies affecting the TS. Seventy dry skulls (140 sides) were used for detailed observation of the TS and SS grooves using gross investigation coupled with transillumination. Bony features such as the mastoid foramen (MF), occipital foramen (OF), granular foveolae (GF), and absence of the TS groove were evaluated, and a classification based on numbers of findings was proposed. The most common internal groove finding was MF (79.3%), followed by absent TS groove (32.9%), and OF (14.3%). MF was statistically more frequent on the left side (91.4%) than the right (67.1%) (p = 0.036); OF was statistically more frequent on the right side (24.3%) than the left (4.3%) (p = 0.008). Absent TS groove was more prevalent on the left side (54.3%) than the right (11.4%) (p = 0.000). A bony prominence (BP) was identified in 15.7% (11 skulls) and there were significant differences from the controls. The type III class (three internal groove findings) was the most prevalent, followed by type II (two findings). The complex and integral role of the bony features described here, and their particularities in normal patients or in those with DVS pathologies, is not well understood

The endonasal approach for treatment of cerebral aneurysms: A critical review of the literature

The last two decades of neurosurgery have seen flourishing use of the endonasal approach for the treatment of skull base tumors. Safe and effective resections of neoplasms requiring intracranial arterial dissection have been performed using this technique. Recently, there have been a growing number of case reports describing the use of the endonasal approach to surgically clip cerebral aneurysms. We review the use of these approaches in intracranial aneurysm clipping and analyze its advantages, limitations, and consider future directions. Three major electronic databases were queried using relevant search terms. Pertinent case studies of unruptured and ruptured aneurysms were considered. Data from included studies were analyzed. 8 case studies describing 9 aneurysms (4 ruptured and 5 unruptured) treated by the endonasal approach met inclusion criteria. All studies note the ability to gain proximal and distal control and successful aneurysm obliteration was obtained for 8 of 9 aneurysms. 1 intraoperative rupture occurred and was controlled, and delayed complications of cerebrospinal fluid leak, vasospasm, and hydrocephalus occurred in 1, 1, and 2 patients, respectively. Described limitations of this technique include aneurysm orientation and location, the need for lower profile technology, and challenges with handling intraoperative rupture. The endonasal approach for clipping of intracranial aneurysms can be an effective approach in only very select cases as demonstrated clinically and through cadaveric exploration. Further investigation with lower profile clip technology and additional studies need to be performed. Options of alternative therapy, limitations of this approach, and team experience must first be considered

Safety and efficacy of intra-arterial fibrinolytics as adjunct to mechanical thrombectomy : a systematic review and meta-analysis of observational data

Background Achieving the best possible reperfusion is a key determinant of clinical outcome after mechanical thrombectomy (MT). However, data on the safety and efficacy of intra-arterial (IA) fibrinolytics as an adjunct to MT with the intention to improve reperfusion are sparse. Methods We performed a PROSPERO-registered (CRD42020149124) systematic review and meta-analysis accessing MEDLINE, PubMed, and Embase from January 1, 2000 to January 1, 2020. A random-effect estimate (Mantel-Haenszel) was computed and summary OR with 95% CI were used as a measure of added IA fibrinolytics versus control on the risk of symptomatic intracranial hemorrhage (sICH) and secondary endpoints (modified Rankin ScalePeer reviewe

Safety and efficacy of intra-arterial fibrinolytics as adjunct to mechanical thrombectomy: A systematic review and meta-analysis of observational data

Background: Achieving the best possible reperfusion is a key determinant of clinical outcome after mechanical thrombectomy (MT). However, data on the safety and efficacy of intra-arterial (IA) fibrinolytics as an adjunct to MT with the intention to improve reperfusion are sparse. Methods: We performed a PROSPERO-registered (CRD42020149124) systematic review and meta-analysis accessing MEDLINE, PubMed, and Embase from January 1, 2000 to January 1, 2020. A random-effect estimate (Mantel-Haenszel) was computed and summary OR with 95% CI were used as a measure of added IA fibrinolytics versus control on the risk of symptomatic intracranial hemorrhage (sICH) and secondary endpoints (modified Rankin Scale ≤2, mortality at 90 days). Results: The search identified six observational cohort studies and three observational datasets of MT randomized-controlled trial data reporting on IA fibrinolytics with MT as compared with MT alone, including 2797 patients (405 with additional IA fibrinolytics (100 urokinase (uPA), 305 tissue plasminogen activator (tPA)) and 2392 patients without IA fibrinolytics). Of 405 MT patients treated with additional IA fibrinolytics, 209 (51.6%) received prior intravenous tPA. We did not observe an increased risk of sICH after administration of IA fibrinolytics as adjunct to MT (OR 1.06, 95% CI 0.64 to 1.76), nor excess mortality (0.81, 95% CI 0.60 to 1.08). Although the mode of reporting was heterogeneous, some studies observed improved reperfusion after IA fibrinolytics. Conclusion: The quality of evidence regarding peri-interventional administration of IA fibrinolytics in MT is low and limited to observational data. In highly selected patients, no increase in sICH was observed, but there is large uncertainty

Crosscurrents: art images/commercial images.|Arthur S. Penn photography symposia.

Recorded in Ithaca, NY by Cornell University., Sponsored by: Herbert F. Johnson Museum of Art., Speaker(s): Curator, writer and book editor., Lecture, April 29, 1989.43 minutesHeiferman describes the uses of photography by the media and shows how the study of photography can be, in actuality, a historical review.1_o5miq2g01_l13jhrs