Edition/Format: eBook: Document: English: Rev. ed. View all editions New and Revised Chapters: Duane's Clinical Ophthalmology -- New and Revised. Table of Contents > Duane's Foundations of Clinical Ophthalmology > Volume . When viewed anteriorly in the living eye, the adult human cornea is somewhat. Clinical and Experimental Optometry Duane's Ophthalmology must rank as the present most comprehensive and authoritative repository of.
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This comprehensive and well-illustrated book provides a reasoned approach to the everyday practice of ophthalmology. This new edition has been updated to. Abstract: Duane retraction syndrome (DRS) is a congenital eye movement anomaly . Common reasons for seeking medical attention in DRS include an abnormal head position of the child, one of Download Article [PDF]. Duane's Clinical Ophthalmology. [-] Volume 1. [+] Ocular Motility and. Strabismus. [+] Refraction and Clinical. Optics. Print Preview. Updated Chapter.
It has seven volumes, including an index, and is updated yearly. Therefore, this reference book has a broader scope over many subfields of vision science and is more up-to-date than a regular textbook.
A random list of citations from the end of each chapter in Duane's Clinical Opthalmology was made. The participating vision science libraries compared their collections to the list.
A second random list was generated from the same book to see if the libraries would come out in relatively the same order for both comparisons. This second list helped determine consistency and increased the sample size. This made a total of references on citation analysis list number one.
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Then another reference was selected randomly from each chapter for an additional list of references, and this became citation analysis list number two. Selection of all citations was made using a random number table. Both lists, a summary sheet, and directions were emailed or mailed to selected AVSL members for them to check their collections.
Each library then returned the summary sheet containing the percentages of books and journals from each list. Percentages were then compared.
Participation was voluntary, and twenty-one out of thirty-six invited libraries from the United States, Puerto Rico, and Canada returned their forms. There were a few duplicate citations between the two lists, and these were included. Only book and journal titles were counted.
If, for example, the picked citation represented unpublished literature, it was disqualified and a new reference picked randomly from the chapter. Each list had a journal section, book section, and a combined number, which were all converted to percentages.
A library could claim to hold a journal article if it owned the title, year, and issue that the article was in. Only paper copies were counted, although if the study is repeated, electronic formats will have to be considered. When comparing the book section, the library had to have the exact edition of a book to count it.
Later, Sinclair 5 , Bahr 6 , Stilling and Bergmann 7 , Turk 8 and several other authors 9 went on to describe this entity in greater detail. It was in that Alexander Duane 1 reported a series of 54 cases with DRS, giving a detailed description of its clinical features and summarizing the possible etiopathogenesis and management of this syndrome. Decades later, with the advent of neuroimaging, muscle electrophysiology and genetic analysis, there has been greater understanding of this form of strabismus, now considered a congenital cranial dysinnervation disorder CCDD , giving better insights into the management of this challenging syndrome.
Wolff 9 similarly described a congenitally anomalous LR, which was inelastic and tight to be the cause of abnormal motility in DRS.
On the other hand, a developmental anomaly leading to a tight LR due to nuclear aplasia or birth trauma was also proposed later. This was well accepted for a long time until lack of this finding intraoperatively in most of the cases made it questionable. Innervational anomalies Possibility of an underlying innervational etiology came into light when Breinin 12 studied the electric potentials generated by muscles in various positions of gaze in DRS.
He found that there was no LR activity recordable in attempted abduction, while maximum LR action potentials were generated in adduction, suggesting that the LR was receiving innervation in adduction.
This was thought to be the cause of co-contraction and globe retraction. Few others 13 , 14 also studied these muscle potentials and found variable degrees of LR potentials from abduction to adduction along with abnormal responses in vertical and oblique gazes.
The MR muscle in all these was found to be normal.
Strachan and Brown 15 quantified this paradoxical innervations using electromyography. They found variable LR activity depending on the position of gaze, while MR spikes were almost always consistent.
Occasionally, synergistic innervation between MR and the vertical rectus muscles and obliques was noted. These findings were further confirmed by Metz 16 who studied the saccadic velocities of eye movements in DRS. The author noted slowing of abduction saccades due to lack of normal LR innervations, along with slowing of adduction saccades, possibly due to paradoxical innervation.
Central nervous system anomalies Understanding muscle electrophysiology in DRS made it evident that the causative etiology was absent normal sixth nerve innervation to the LR, either nuclear eg, anomalous innervation by the oculomotor nerve or supranuclear eg, brainstem abnormality in origin.
While some authors have found abducens nucleus hypoplasia 17 or complete absence 18 in the brain stem to be the cause of DRS, others 19 have proposed that infranuclear abnormalities at the level of cavernous sinus, where the oculomotor and abducens nerves are in vicinity of each other, lead to features of DRS.
These early attempts to understand the neurologic basis of DRS were only based on autopsy studies. Further evidence to support the role of neurologic anomalies in DRS is the presence of synkinesis, 20 which is occasionally seen with DRS, for example, Marcus Gunn Jaw Winking phenomenon, crocodile tears etc. Also, it has been suggested that unilateral abducting nystagmus in the normal eye of DRS patients is a marker of brainstem abnormality indicative of a central neurologic anomaly.
This congenital absence of innervation to the muscles has been found to cause fibrotic changes in the extraocular muscles leading to abnormal motility in DRS, a concept which has evolved over the last decade to be known as CCDD. This may be primary due to absence of normal innervation or secondary following aberrant innervations from other cranial nerves.
CCDD is a nonprogressive entity and may also have associated bony abnormalities. This gene mutation is said to affect the abducens and less commonly, the oculomotor nerve. This was studied by the analysis of a dominant DRS pedigree. This syndrome has been mapped to heterozygous nonsense frameshift and deletion mutations in SALL4 gene on chromosome These finally determined the laterality and presentation of DRS. Patients with sporadic DRS have also been found to have associated congenital malformations.
Pfaffenbach and Cross 35 studied these anomalies which were skeletal, auricular, ocular or neural in presentation. William Tasman and Edward A Jaeger. Philadelphia : Lippincott , There is no doubt that every optometrist should have access to it.
In theory, the DVD format should unlock the treasure chest of information contained in Duane's Ophthalmology by making it more accessible on your desktop or laptop computer.
The analogy fails because the treasure chest on the DVD is just as securely locked as that piratical treasure chest of fiction, at least for my Macintosh computer. When reviewing the edition of this product I made harsh comments about the difficulty of use on the Macintosh platform.Vision Res. While some authors have found abducens nucleus hypoplasia 17 or complete absence 18 in the brain stem to be the cause of DRS, others 19 have proposed that infranuclear abnormalities at the level of cavernous sinus, where the oculomotor and abducens nerves are in vicinity of each other, lead to features of DRS.
This adduction deficit is evident from the fact that DRS patients have a remote near point of convergence. Surgical approach to these patients is challenging and must be individualized based on the amount of ocular deviation, abnormal head position, associated globe retraction and overshoots. Although intelligence is usually normal in DRS, intellectual disability has been reported in a few cases of DRS with borderline intelligence and cases of autism spectrum disorder associated with fetal thalidomide exposure or HOXA1-related syndromes.
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