Frequency of prepapillary vascular loops in Congolese patients.

PURPOSE: To determine the frequency of prepapillary vascular loops in the population of Congolese patients. METHODS: We performed a retrospective cross-sectional and descriptive analysis of the data collected between January 2005 and August 2014 from patients diagnosed with prepapillary vascular loops, in an outpatient eye clinic, a general ophthalmology practice. RESULTS: Out of 16,016 patients seen during the study period, 24 patients (27 eyes) were diagnosed with prepapillary vascular loops, for a frequency of 0.15%. The mean age of the patients with prepapillary vascular loops was 37.8 years±14 (SD) (range, 18 to 60 years). Male were more frequently diagnosed with prepapillary vascular loops than female (62.5% vs 37.5%). Unilateral prepapillary vascular loops were found in 77.8% and bilateral in 22.2% of eyes. Most of PPLs were estimated to be arterial (88.9% of eyes) based on clinical observation alone, as fluorescein angiography was not systematically performed. Ophthalmoscopically, the vessels appeared as simple (44.6%) or took more serial turns (corkscew or spiral-shaped) (55.6%). The average length of PPLs was 1.02mm (range 0.6 to 1.5mm) with an orientation (an axis orientation) in the superior nasal sector (50%), inferior nasal sector (33%) and superior temporal sector (17%); and a mean axis of 143° relative to the horizontal. Refractive errors were found in 16 eyes (59.3%) and included simple myopia (4 eyes, 14.8%), myopic astigmatism (8 eyes, 29.6%), hyperopic astigmatism (one eye, 3.7%), hyperopia (3 eyes, 11.1%); One patient (one eye, 3.7%) with high hyperopia had anisometropia. Primary open angle glaucoma was found in 5 (18.5%) eyes; vascular tortuosity was seen in two (7.4%) eyes. No complication such as retinal arterial occlusion, vitreous hemorrhage, or any other complication was found. CONCLUSION: The frequency of 0.15% found in this study suggests that although rare, prepapillary vascular loops seem to be a bit more common in black people than in white and Asian people. An association between PPLs and refractive errors may be possible.

Accessory (multiple) renal arteries - Differences in frequency according to population, visualizing techniques and stage of morphological development.

The aim of this paper is to comprehensively analyze the literature focused on frequency of the presence of the accessory renal arteries in the human body. A systematic analysis of papers has been made. With regard to ethnicity, the incidence of accessory renal arteries fluctuates from 4% in a Malaysian population to 61.5% in a Brazilian population. The frequency is lowest in eastern and southern Asia (from 4% to 18.4%). In some, not ethnically homogenous populations, wide span of occurrence of accessory renal arteries is described (e.g. American - averaging from 18% to 28.8%). A higher frequency of accessory renal arteries was observed in fetuses compared to adults. Moreover, differences in the presence and number of accessory renal arteries reported in different papers are a consequence of type of visualizing technique used in research - especially when computed tomography and anatomical dissection were compared. The increasing number of surgical interventions, especially where laparoscopic methods are concerned, underlines the importance of such knowledge especially to surgeons, interventional radiologists, nephrologists, and vascular surgeons.

Patterns of superficial veins of the middle upper extremity in Caucasian population.

PURPOSE: Superficial veins of the middle upper extremity are frequently variable in existence and arrangement. The superficial veins are clinically important in many revascularization procedures, particularly reconstructive microsurgery and arterial bypass surgery as well as intravenous injection or therapy. The aim of this study was to assess the patterns of superficial veins of middle upper extremity in healthy volunteers. METHODS: We examined both arms of 169 people. A tourniquet was applied at the mid-arm and a drawing made of the pattern of veins. It took about 1-3 min for each arm. We then examined the 338 drawings looking for similar patterns. The study took place in Department of Anatomy, Faculty of Medicine in Novi Sad, Serbia. RESULTS: We found nine patterns of middle upper extremity veins. The most common was an 'M'-shaped pattern (115/338, 34%) followed by an 'N'-shaped pattern (97/338, 29%). CONCLUSIONS: There are only nine basic patterns of middle upper extremity venous anatomy. Some are more common than others. This knowledge should help those needing venous access for medical procedures (venepuncture, transfusion, infusion, cardiac catheterization, placement of dialysis access).

What is the true incidence of anomalous bovine left common carotid artery configuration?

BACKGROUND: Earlier studies have indicated that bovine left common carotid artery configuration occurs in 10.2-22% of patients and increases the complexity of navigating endovascular devices in the aortic arch. However, we anecdotally noted a higher incidence of bovine arch among angiosuite outpatients in Los Angeles, California. Thus, we retrospectively reviewed aortic arch angiograms performed in 93 unique outpatients to determine the true incidence of this anomalous configuration. METHODS: We were able to obtain complete angiographies from clinical data on 90 patients (mean age 50 years, SD 15.23 years, range 17-88 years) from May 2006 to January 2012. Angiograms were categorized as: normal arch; bovine arch with brachiocephalic trunk; bovine arch with common trunk; or indeterminate. RESULTS: The findings indicated an overall 35.16% bovine arch incidence, of which 78.13% is bovine arch with common trunk and 21.88% is bovine arch with brachiocephalic trunk. There was a higher prevalence in the women (40%, n = 60) than men (26.67%, n = 30). Caucasians had a lower incidence of bovine arch (27.78%, n = 47) compared with other ethnicities. The prevalence of bovine arch in different ethnicity and gender groups was assessed and the differences were not statistically significant. CONCLUSIONS: The incidence of bovine left common carotid artery is higher than previously reported and varies by gender and race. Advanced knowledge of the high prevalence of this anomaly could reduce the risks and increase the efficiency of navigating catheters through the tortuous vessels during endovascular procedures. The clinical implications of this report warrant further investigation.

Anatomical characteristics of the thoracic aortic arch in an Asian population.

BACKGROUND: Endovascular repair of the aortic arch is often unsatisfactory due to poor stent-vessel conformity and inadequate landing zones. OBJECTIVE: To study the anatomical characteristics of the aortic arch and provide basic information for the development of arch-specific endovascular devices. MATERIALS AND METHODS: Three-dimensional models were reconstructed in Mimics (image segmentation software) from computed tomography aortograms of 120 elderly Asian patients, by manual segmentation. The centerline of each Three-dimensional aortic model was calculated using a repulsive force field method. Measurements of the aorta and supra-aortic branches were analyzed using Patran (finite-element software). A three-dimensional statistical aortic arch model was built using principal component analysis. RESULTS: The mean diameters of the ascending and descending aorta, and the origins of the innominate, left common carotid, and left subclavian artery were 39.4 ± 6.7, 34.5 ± 7.9, 18.0 ± 3.8, 12.6 ± 2.7, and 14.1 ± 2.5 mm, respectively. The length of the ascending aorta, innominate to left common carotid artery, and left common carotid to left subclavian artery were 62.6 ± 11.4, 12.0 ± 5.6, and 18.7 ± 5.6 mm along the centerline. The mean angle of curvature was 103.8 ± 25 degrees. Principal component analysis of the three-dimensional centerlines derived 3 main modes of variation, which account for 61% of the overall shape range. CONCLUSION: Aortic arch anatomical information from an elderly Asian population can be useful for the development of future endovascular devices.

Role of multidetector-row computed tomography in evaluation of living renal donors.

OBJECTIVES: To assess the value of multidetector-row computed tomography (MDCT) in evaluation of the anatomy of living kidney donors and to reveal the prevalence of renal vascular variations in a Chinese population. PATIENTS AND METHODS: One hundred four potential donors underwent MDCT, and the data sets were postprocessed for reformatted images using maximum intensity projection, a volume-rendering technique, and multiplanar re-formation. Nephrectomy was performed in 97 donors, which enabled correlation of MDCT evaluation with the actual anatomy at surgery as the standard of reference. RESULTS: The MDCT images accurately demonstrated the anatomical structure of the main renal arteries and veins and the upper part of the ureters. The prevalence of accessory arteries was 41.7% (43 of 103), and of early branching was 12.6% (13 of 103). Compared with findings during surgery, the detection rate of accessory arteries on MDCT images was 91.3% (21 of 23), of larger accessory arteries (>1.5 mm in diameter) was 100%, and of early branching was 100%. CONCLUSION: Multidetector-row computed tomography is helpful in accurately evaluating the renal anatomy of potential donors, thus facilitating planning of surgery.