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The A-value used in cochlear duct length (CDL) estimation does not take malformed cochleae into consideration. The objective was to determine the A-value reported in the literature, to assess the accuracy of the A-value measurement and to evaluate a novel cochlear measurement in distinguishing malformed cochlea. High resolution Computer Tomography images in the oblique coronal plane/cochlear view of 74 human temporal bones were analyzed. The A-value and novel C-value measurement were evaluated as predictors of inner ear malformation type. The proximity of the facial nerve to the basal turn was evaluated subjectively. 26 publications report on the A-value; but they do not distinguish normal vs. malformed cochleae. The A-values of the normal cochleae compared to the cochleae with cochlear hypoplasia, incomplete partition (IP) type I, -type II, and -type III were significantly different. The A-value does not predict the C-value. The C-values of the normal cochleae compared to the cochleae with IP type I and IP type III were significantly different. The proximity of the facial nerve to the basal turn did not relate to the type of malformation. The A-value is different in normal vs. malformed cochleae. The novel C-value could be used to predict malformed anatomy, although it does not distinguish all malformation types.

Inadequate design of emergency departments (EDs) is a major cause of crowding, increased length of stay, and higher mortality. The main reason behind this inadequacy is the lack of stakeholders' involvement in the design process. This work reports and analyzes the results of a large survey of the requirements of ED stakeholders. It then compares these requirements with existing designs on the one hand and international standards on the other. Further, we propose a new hybrid design which combines the requirements of both the stakeholders and international standards using quality function deployment (QFD), also known as the House of Quality, method. The proposed method was used to assess two existing EDs located in two countries. The analysis of the survey responses showed certain discrepancies between stakeholder requirements and the existing designs such as the absence of an initial admission unit and insufficient space of the treatment unit. The results showed a strong correlation between the QFD-based design and stakeholder requirements (r = 0.92 for ED1 and r = 0.93 for ED2) which is attributed to the incorporation of stakeholders' opinions into the QFD method. The new design was also positively correlated to the international standards (r = 0.94 for ED1 and r = 0.91 for ED2). Our findings suggest that international design standards should be based on more structured methods for incorporating stakeholders' views and that a certain degree of difference should be allowed depending on the region in which the hospital is located to reflect both cultural and environmental differences.

Objectives: To understand the growth rate of mastoid thickness and skull width associated with the age for both normal and malformed inner-ear anatomy groups. Also, to determine if there is any mathematical relation between cochlear size as measured by the “A” value against the age, mastoid thickness, and skull width. Methods: Ninety-two computed tomography image datasets of human temporal bone were made available that contained normal (n = 44) and malformed inner-ear (n = 48) anatomies. The age of the subjects ranged from 6 months to 79 years. CE marked OTOPLAN preplanning otology software was used to load the patient's preoperative images for making all the measurements including mastoid thickness, skull width, and the cochlear size as measured by the “A” value. Mastoid thickness was measured both in axial and coronal planes starting from the cochlear entrance to the skull surface, with the line in plane with the basal turn of the cochlea. Skull width was measured from side to side in both axial and coronal planes from the image slice that gave the highest width. The cochlear size in terms of basal turn diameter “A” was measured from “Cochlear View” in the oblique coronal plane. Results: Mastoid thickness and skull width increased with age in a logarithmic manner. The mastoid thickness increased from a minimum of 17 mm to around 34 mm and the skull width increased from 105 mm to around 146 mm as the age increased from 6 months to 20 years. At the age of around 20, both the mastoid thickness and skull width reached the plateau and thereafter with a very little growth. The skull width was linearly correlated with the mastoid thickness conveying the fact that bigger the head size is, thicker will be the mastoid. The size of the cochlea as measured by the “A” value did not have any meaningful correlation with the age, mastoid thickness, and skull width. This conveys the message that the cochlear size is independent of the overall size of head and the age of patient. Conclusions: Mastoid thickness and skull width increased with age, while the cochlear size was independent of age, mastoid thickness, and the size of the skull.

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