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We describe the first two observations of paracentral acute middle maculopathy after cardiac surgery involving cardiopulmonary bypass. Bilateral cotton-wool spots and unilateral ischemic optic neuropathy were also observed. We discuss possible mechanisms of multifocal microvascular nonperfusion in the setting of extracorporeal oxygenation and circulation of blood. Purpose: To report the first two observations of bilateral paracentral acute middle maculopathy in the early postoperative period after cardiopulmonary bypass procedures. Methods: Comprehensive ophthalmic examinations were performed, including best-corrected visual acuity, Humphrey visual field testing, dilated fundus examination, and optical coherence tomography. Results: Two patients complained of unilateral vision loss after cardiac surgery involving cardiopulmonary bypass. Unilateral optic disc edema consistent with ischemic optic neuropathy was observed in the symptomatic eye of each patient, whereas scattered cotton-wool spots were identified bilaterally. In addition, optical coherence tomography imaging revealed bilateral paracentral acute middle maculopathy, correlating with visual field defects detected on automated perimetry in the asymptomatic eyes. Conclusion: Although symptomatic postoperative vision loss is a rare complication of cardiac surgery, intraoperative retinal microvascular nonperfusion as a consequence of extracorporeal circulation of blood may be a more common and under-recognized occurrence. [ABSTRACT FROM AUTHOR]

The optic nerve is a white matter tract of the brain and its sheath is composed of pia mater, arachnoid mater, and dura mater. The subarachnoid space (SAS) of the optic nerve sheath, which contains cerebrospinal fluid, is contiguous with the SAS of the brain. Elevated intracranial pressure is transmitted to the optic nerve head through the SAS resulting in papilledema. Optic nerve sheath fenestration (ONSF) can be an effective surgical technique to preserve vision in patients with progressive optic neuropathy due to papilledema caused by idiopathic intracranial hypertension (IIH); however, a dreaded complication of ONSF is visual loss. This article will discuss the rationale, indications, and complications of ONSF. A variety of surgical techniques can be employed to perform an ONSF. In particular, the medial transconjuctival approach will be highlighted. [ABSTRACT FROM AUTHOR]

This article analyses the impact of party systems on human well-being and argues that multiparty systems are associated with better welfare outcomes for two primary reasons: first, multiparty systems provide representation to multiple issue-dimensions in society, thereby indicating a more inclusive system, which ensures that diverse societal interests are taken into account during formulation of welfare policies. Second, multiparty systems also indicate a competitive party system, which provides incentives for parties to perform effectively while in office and propels parties to appeal to multiple segments of society by providing broader welfare services. The impact of party systems on human well-being is tested on a global sample of 68 democratic countries from 1975–2000. The findings show support for the hypothesized relationship between party systems and human well-being. [ABSTRACT FROM PUBLISHER]

This retrospective study investigates the potential of image analysis to quantify for the presence and extent of pulmonary hypertension secondary to sickle cell disease (SCD). A combination of fast marching and geodesic active contours level sets were employed to segment the pulmonary artery from smoothed CT-Angiography images from 16 SCD patients and 16 matching controls. An algorithm based on fast marching methods was used to compute the centerline of the segmented arteries to measure automatically the diameters of the pulmonary trunk and first branches of the pulmonary arteries. Results show that the pulmonary trunk and arterial branches are significantly larger in diameter in SCD patients as compared to controls (p-values of 0.002 for trunk and 0.0003 for branches). For validation, the results were compared with manually measured values and did not demonstrate significant difference (mean p-values 0.71). CT with image processing shows great potential as a surrogate indicator of pulmonary hemodynamics or response to therapy, which could be an important tool for drug discovery and noninvasive clinical surveillance.