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Disorders of the Orbit
Published in John C Watkinson, Raymond W Clarke, Louise Jayne Clark, Adam J Donne, R James A England, Hisham M Mehanna, Gerald William McGarry, Sean Carrie, Basic Sciences Endocrine Surgery Rhinology, 2018
Nithin D. Adappa, James N. Palmer
An ophthalmologist will often perform a fluorescein dye disappearance test in the office. Fluorescein is applied to the eye and after 10–15 minutes a bluelight filter is used to attempt to identify fluorescein runoff into the nose. Radiographic tests include a dacrocystogram, which can identify diverticula, stenosis, strictures, dacryoliths or a tumour. Dacryoscintigraphy uses radionucleotide. 99mTc also may be helpful when identifying for a functional obstruction when there is free flow on a syringe test along with an abnormal fluorescein dye disappearance test. Computed tomography (CT) is generally not indicated unless there is suspicion for neoplastic etiology or history of midface trauma requiring further evaluation.
Tear transit time evaluation using real-time technique for dynamic MR dacryocystography
Published in Orbit, 2021
Swati Singh, Anuj Dhull, Dinesh Selva, Mohammad Javed Ali
The physiology of the tear drainage is ill-understood even though substantial knowledge exists with regards to the anatomy of lacrimal drainage system (LDS).1,2 One important aspect in this regard is the tear transit time through the LDS. The reported transit times for tears to reach the nasal cavity from the conjunctival sac are highly variable with earlier studies even reporting absence of contrast detection in 25–30% subjects.3,4 In the past, saccharin test, Jones test, and dacryoscintigraphy (DSG) have all been utilized for the dynamic documentation of contrast outflow through LDS; however, these tests either employ non-physiological methods (cannulation technique and irrigation) or lack spatial resolution. Dacryoscintigraphy has long been considered the front-runner for physiological assessment but poor resolution limits its practical application in localizing the site of anatomical or functional delay.5 Better appreciation of soft tissue details and absence of ionizing radiation exposure makes MRDCG an imaging of choice for evaluating the transit time under physiological conditions.6,7
Influence of mouth and jaw movements on dynamics of spontaneous eye blink activity assessed during slitlamp biomicroscopy
Published in Clinical and Experimental Optometry, 2018
A slitlamp head/chin rest has been used to study lacrimal kinetics by dacryoscintigraphy with subjects asked not to blink or to ‘blink normally’,1991 and a slitlamp‐based system has also been used for video observation of tear lipid layers in relation to eye blink activity with subjects being asked to ‘blink naturally’.1994 Similarly, in studies of the effect of contact lens wear on eye blink activity, subjects were positioned at a slitlamp‐type apparatus and asked to ‘hold head and eyes steady and look straight ahead’.1973 Eye blink completeness has also been qualitatively assessed while subjects were seated at the slitlamp.2014
Comparison of a manometric tear duct irrigation test with dacryoscintigraphy in the investigation of epiphora
Published in Orbit, 2020
Zuzana Sipkova, Ebube E. Obi, Oyinka Olurin, Peter M. Mota, Oana Vonica, Andrew R. Pearson
Dacryocystorhinostomy (DCR) surgery provides a low resistance channel for tear drainage. It is effective in treating epiphora in those with both complete nasolacrimal duct obstruction as well as those with duct stenosis and there is evidence that success is highest in those with more severe stenosis.1 Deciding on which patients with incomplete obstruction of the nasolacrimal duct would benefit from surgery is not straightforward. It usually relies on a combination of clinical examination, including lacrimal syringing, and investigations such as dacryoscintigraphy (DSG) and dacryocystography (DCG).