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Blepharoplasty
Published in John C Watkinson, Raymond W Clarke, Terry M Jones, Vinidh Paleri, Nicholas White, Tim Woolford, Head & Neck Surgery Plastic Surgery, 2018
The height and curvature of the upper eyelids relative to the pupils should be noted, and the MRD-1 and MRD-2 should be measured and recorded, looking for any evidence of true blepharoptosis. (The marginal reflex distance-1 (MRD-1) is the distance between the centre of the pupillary light reflex and the upper eyelid margin with the eye in primary gaze. A measurement of 4–5 mm is considered normal. The marginal reflex distance-2 (MRD-2) is the distance between the center of the pupillary light reflex and the lower eyelid margin with the eye in primary gaze.)
Transverse Overcurvature
Published in Nilton Di Chiacchio, Antonella Tosti, Therapies for Nail Disorders, 2020
Beyond mechanobiology, the shape of the underlying distal phalanx has been theorized to contribute to the overcurvature of the nail unit.7 The distal tip of the phalanx is often described to have an osteophyte or upward protrusion of the boney tip when viewed on a lateral radiograph. Also, it has been thought that a widening of the base of the distal phalanx contributes to the pincer nail deformity.8 Kosaka et al.'s study to determine the distal phalanx's influence on nail shape assessed 60 great toes from patients with “normal” nails, ingrown nails, and pincer nails.7 Osteophytes of the distal phalanx were confirmed in 50%, 80%, and 100% of cases in the normal, ingrown and pincer nail groups, respectively.7 The width and the height of pincer nails that were avulsed surgically were also measured. A statistically significant level between width and height of the nail plate was found compared to the same measurements in normal and ingrown nails. The distal narrowing of the pincer nail bed described in the literature is consistent with the width/height (or curvature) index in this study, but the investigators sought to explain the “shrinkage” of the nail bed. Ultimately, they theorized that an unknown cause creates nail bed shrinkage, which causes the ventral nail plate to shrink, but the dorsal nail plate continues to progress normally. This variation causes an inward twisting distally, and the lateral nail margins to roll inwardly. This “continuous traction” on the distal phalanx exerts force on the apex of the distal phalangeal tuft creating a secondary deformity to the primary nail deformity.7 Ultimately, the distal phalanx does not seem to cause the pincer nail; rather the pincer nail causes the bone deformity, or osteophyte, to develop.
In Vitro Biomechanical Study of Epidural Pressure during the Z-shape Elevating-Pulling Reduction Technique for Cervical Unilateral Locked Facets
Published in Journal of Investigative Surgery, 2019
Xinwei Shao, Jican Zeng, Yuchun Chen, Lixian Wu, Xinjia Wang
A halo vest comprisesTABLE 1a ‘halo ring’ that is secured to the skull with skull pins and a rigid, fleece-lined vest. The vest is attached to the halo ring with adjustable metal rods or struts. Closed reduction was attempted with the halo vest-assisted Z-shape elevating-pulling reduction technique in three main steps. To aid understanding, each screw of the halo vest is shown in Figure 2a. Step 1 involved loosening bolts A (A′), B (B′), and D (D′). The rear of the head ring was connected to two struts while it was lifted upwards by 2–3 cm. D (D′) was then tightened. In step 2, after loosening bolt C (C′), the front of the head ring was connected to two struts while it was lifted upwards by 2–4 cm and tightened. A C-arm radiograph system was used for perspective. Steps 1 and 2 were repeated until the unilateral perched facet position was shown (i.e., a ‘tip-to-tip’ appearance was shown as in Figure 3b). In step 3, after simultaneously loosening C (C′) and D (D′), the contralateral side was moved down by 2–3 cm. Hence, the ipsilateral side was lifted upwards by 1–2 cm, and the head tilted toward the healthy side so that reduction could be achieved. Then the struts connected to the head ring were gradually lowered to restore the normal height and curvature of the cervical spine. The procedure is illustrated in Figure 4. During this process, radiographic examination and CT scanning were performed (Figure 5), and the epidural pressures were measured.
Optical coherence tomography and scleral contact lenses: clinical and research applications
Published in Clinical and Experimental Optometry, 2019
Stephen J Vincent, David Alonso‐caneiro, Michael J Collins
A number of methods have been used to determine the curvature of the anterior sclera, including measurements obtained from cadaver eyes and ocular impressions,1988 and more recently Scheimpflug imaging and anterior eye profilometry.2017 In order to obtain the profile of the ocular surface for scleral contact lens fitting, as early as 1888,1988 an impression of the eye was used to make a mould from which a lens could be cast that provided a realistic estimate of both corneal and scleral height and curvature along all meridians. However, impression moulding was variable and dependent upon examiner skill. Lenses manufactured from impression moulding still required numerous modifications to adjust the final fit to minimise conjunctival blanching or increase corneal clearance, due to the somewhat unpredictable nature of the lens settling on the eye.