Publications by authors named "Cameron F Parsa"

Background: Rare autopsy studies have described smaller kidneys as well as urinary tract anomalies in Down syndrome. This observation has never been investigated in vivo and little is known about the possible consequences upon kidney function. Here we wish to confirm whether children with Down syndrome have smaller kidneys and to evaluate their kidney function in vivo.

View Article and Find Full Text PDF

Wölfflin nodules and Brushfield spots were described essentially in light colored irides. The purpose of our study is to determine if these iris features are also present in dark irides, hidden by melanin granules of the anterior leaf of the iris. We examined iris images, taken with standard visible white, as well as with near-infrared light of children with Down syndrome and without.

View Article and Find Full Text PDF

Background: Variable pupillary responses have been described with carotid-cavernous sinus fistulas. These often are associated with a decrease in visual acuity and attributed to retinal ischemia. We propose a novel pathophysiologic mechanism for changes in pupillary reactivity involving anatomic changes secondary to choroidal effusion.

View Article and Find Full Text PDF

Purpose: To assess the effects of 360-degree laser retinopexy on human corneal subbasal nerve plexus and to investigate correlations among corneal subbasal nerve plexus density, corneal epithelial thickness, and corneal sensitivity.

Design: Prospective, observational, nonrandomized study.

Participants: A total of 15 eyes of 15 patients who underwent pars plana vitrectomy (PPV) with 360-degree laser retinopexy for retinal detachment (RD) and 15 eyes of 15 patients who underwent PPV for macular hole (MH) without laser treatment.

View Article and Find Full Text PDF

Purpose: To provide an in-depth re-examination of assumed causes of tissue hypertrophy, port-wine stains, and the Sturge-Weber, Cobb, Klippel-Trénaunay, and related syndromes to support an alternative unifying pathophysiologic mechanism of venous dysplasia producing focal venous hypertension with attendant tissue responses; to provide proof of concept with new patient data; to propose a novel etiological hypothesis for the venous dysplasia in these syndromes and find supportive evidence.

Methods: Data from 20 patients with port-wine stains and corneal pachymetry readings was collected prospectively by the author in an institutional referral-based practice. The literature was searched using MEDLINE, and articles and textbooks were obtained from the bibliographies of these publications.

View Article and Find Full Text PDF

Objective: To propose a pathophysiologic mechanism to unify a variety of disparate sporadic congenital malformations.

Methods: Inductive and deductive analyses to correlate malformation laterality with asymmetries in thoracic anatomy, critical analysis of malformations with female predominance, and concepts of hydrodynamic pressure gradients in vascular growth were applied to the ensuing development of guiding tissue scaffolds for cellular proliferation, differentiation, and apoptosis.

Results: Duane syndrome may develop following a focal vascular insult to the sixth nerve trunk with axonal degeneration, allowing for substitutive innervation from third nerve axons to the lateral rectus muscle.

View Article and Find Full Text PDF

Assessment of ocular torsion via fundus examination is an important tool for diagnosis and management of cyclorotational disorders. The widely used disc-macula relationship for quantification of ocular torsion possesses inherent limitations, which restricts its use in some clinical scenarios. An accessory technique of fundus examination for assessing torsion is hereby proposed using vascular cues.

View Article and Find Full Text PDF

Background: A new pathophysiologic mechanism has been proposed that indicates that periorbital port-wine birthmarks (PWBs) serve as alternate collateral blood passageways when orbital venous drainage is impaired. The occlusion of such collateral venous channels could, therefore, potentially exacerbate impaired ocular venous flow and trigger the development or worsening of glaucoma in patients with Sturge-Weber syndrome. We investigated to what extent a single application of laser therapy, which occludes only the most superficial portions of a facial PWB, might affect intraocular pressure.

View Article and Find Full Text PDF