PubMed Health⌕ Search
Home/Archive/PubMed

PubMed · 2769768

Slab-off prisms.

N R Garber·T Kirdulis
View original source ↗Export metadata ↓

Abstract

1. There are three grinding techniques for slab-off prism effects: front surface slab-off; bicentric grinding; and reverse slab-off. 2. The front surface slab-off and bicentric produce base-up prism in the lower section of the lens. Reverse slab-off produces base-down prism in the inferior portion of the lens. 3. The slab-off prism process is used to correct vertical diplopia in the reading position. Use of slab-off prism in glasses is expensive and should only be considered for stable deviations.

Explore related subjects

DiplopiaEyeglassesHumansOptics and PhotonicsPatient Education as TopicReadingJournal Article

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

N R Garber, T Kirdulis. Slab-off prisms.. https://pubmed.ncbi.nlm.nih.gov/2769768/

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed1992

A scoring method for Hess charts.

A new scoring system for Hess charts is described. Scores for both horizontal and vertical deviations are calculated from the displacement of individual points on the Hess chart, using weighting factors for the centre, inner and outer zones. The scoring system was validated in a group of 24 patients undergoing surgery for paralytic or restrictive strabismus. Subjective scores were obtained from patients both before and after corrective surgery, and corresponding Hess charts were scored using the new system. There was a good correlation between the changes in subjective and objective score. Our scoring system has applications in both research and clinical practice, allowing objective analysis of changes in muscle balance in a variety of motility disorders.

Diplopia↗
PubMed1992

Ophthalmic consequences of mid-facial trauma.

Fractures of the mid-face are commonly accompanied by injury to the visual system. Three hundred and sixty three patients who had sustained mid-facial fractures were assessed prospectively for evidence of such injury. The data have been used to devise a scoring system for the maxillofacial surgeon in order to help identify those patients at risk of eye injury. The scoring system has been evaluated on a further cohort of 100 patients with a similar spectrum of injury and the sensitivity and specificity of the system have been determined. The results of these studies have been reported in the maxillofacial literature. This paper reviews the data and results obtained. In summary, impaired visual acuity with a comminuted or out blow fracture, a motility abnormality, or facial fracture combined with head injury, sufficient to cause both retrograde and post-traumatic amnesia, emerged as major risk factors which are indicative of an adverse ophthalmic outcome deemed to warrant referral. The scoring system which was developed from this data was found to have a sensitivity of 94.4% and a specificity of 89% for the detection of patients thought to merit ophthalmic assessment. Failure to assess central visual function as objectively as practicable in patients who have sustained mid-facial fractures may lead to potentially treatable ophthalmic pathology not being identified.

Diplopia↗