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Central nervous system
Published in A Stewart Whitley, Jan Dodgeon, Angela Meadows, Jane Cullingworth, Ken Holmes, Marcus Jackson, Graham Hoadley, Randeep Kumar Kulshrestha, Clark’s Procedures in Diagnostic Imaging: A System-Based Approach, 2020
A Stewart Whitley, Jan Dodgeon, Angela Meadows, Jane Cullingworth, Ken Holmes, Marcus Jackson, Graham Hoadley, Randeep Kumar Kulshrestha
The lacrimal system comprises the lacrimal gland, which secretes tears, the lacrimal sac and the ducts through which the tears pass into the nasal cavity (Figs 11.59a–c). The lacrimal gland lies anteriorly in the upper outer quadrant of the orbit and communicates with the lacrimal sac via the lacrimal canaliculi. Tears wash over the surface of the eye and drain through the lacrimal canaliculi into the lacrimal sac through two openings, the puncta lacrimalia, which are situated on the medial aspects of the upper and lower eyelids. The lacrimal sac drains into the nasolacrimal duct, which runs vertically through the lateral nasal wall on the medial aspect of the maxillary antrum. The nasolacrimal duct opens into the nasal cavity below the inferior nasal conchus.
The lacrimal system and tear film
Published in Mary E. Shaw, Agnes Lee, Ophthalmic Nursing, 2018
The lacrimal system (Figure 7.1) consists of The lacrimal glandThe lacrimal drainage system comprising PunctaCanaliculiLacrimal sacNasolacrimal duct
Lacrimal Disorders in Children
Published in John C Watkinson, Raymond W Clarke, Christopher P Aldren, Doris-Eva Bamiou, Raymond W Clarke, Richard M Irving, Haytham Kubba, Shakeel R Saeed, Paediatrics, The Ear, Skull Base, 2018
Caroline J. MacEwen, Paul S. White
The lacrimal system consists of a secretory portion and a drainage system. The secretory portion is made up of the lacrimal and accessory lacrimal glands which, together with the Meibomian glands and the goblet cells, secrete the components of the tear ï¬lm. The accessory lacrimal glands produce basal tear secretion, and the lacrimal gland is largely responsible for reflex tearing in response to noxious or emotional stimuli. The drainage system consists of the lacrimal puncta, canaliculi, lacrimal sac and nasolacrimal duct (Figure 25.1). This active system pumps tears from the conjunctival sac into the inferior meatus of the nose. Clinical problems with the lacrimal system in children usually relate to the reduced drainage of tears. The underproduction of tears, causing dry eyes, is rare but more serious due to the potential for sight-threatening consequences.
Living a dream: Establishment of an Institute of Dacryology
Published in Orbit, 2022
Modern medicine has witnessed the evolution and establishment of numerous subspecialties, and Dacryology is a recent addition to the list.1–3 Dacryology is the science of tears and their drainage through the lacrimal system into the nasal cavity. This branch is mostly practiced by Ophthalmologists (mainly the oculoplastic surgeons) and Otorhinolaryngologists. To advance the science, a society, “International society of Dacryology’, initially referred to as “Internationalis Societas Dacryologiae” was formed in 1982 at Lubbock in the United States during the international tear film symposium. Subsequently, the society conducts triennial conferences featuring advances in lacrimal sciences. With the rapid pace of developments in Oculoplastic surgery pertaining to imaging, surgical techniques, education, and research, lacrimal sciences got a parallel boost. They are increasingly becoming a subject of interest to numerous Oculoplastic surgeons worldwide.
Evaluation of Ultrasound Biomicroscopy Combined with Color Doppler Flow Imaging in the Diagnosis of Primary Lacrimal Canaliculitis
Published in Ocular Immunology and Inflammation, 2021
Qian Chen, Ruiqi Ma, Xiuqian Yi, Lu Gan, Yun Cheng, Rui Zhang, Jiang Qian, Yifei Yuan
Primary lacrimal canaliculitis is an uncommon infection of the canaliculus. The incidence is relatively low, reported as 1.4–2.0% in lacrimal system diseases.1 Its classic symptoms include pouting punctum, punctal discharge, conjunctival congestion, medial canthal erythema, epiphora, and so forth. The atypical presentations can masquerade as other ocular conditions, such as conjunctivitis, blepharitis, hordeolum, dacryocystitis, and mucocele. Lacrimal canaliculitis was reported with a high misdiagnosis rate, ranging from 45% to 100% in previous documents.2 To obtain definitive diagnosis requires successful isolation of the microbial pathogens. The most common causative organism is considered to be Actinomyces, but its yield rate is relatively low due to the fastidious nature and the difficulty of culturing this anaerobic bacterium.3 To solve this problem, some researchers perform histopathologic staining to identify pathogens in cases with intracanalicular concretions.4 Concerning the time-consuming procedures of microbiologic and histopathologic studies, clinicians need a more efficient ancillary test to assist the diagnosis of canaliculitis.
Congenital canaliculops with punctal agenesis: is there a possibility to establish patency?
Published in Orbit, 2020
Nandini Bothra, Gayatri Krishnamurthy, Mohammad Javed Ali
Canaliculops is a non-inflammatory and non-infectious distention of canaliculus, which is filled with serous fluid secreted by the mucosa.1–3 Association of canaliculops with punctal agenesis has been described only twice previously, however, the medial end of the canaliculops was blind.4,5 Of the eight convincing cases of canaliculops described so far, lacrimal system patency was established in only one case so far, with a mini monoka being placed within the lumen and canalicular edges sutured over it. However, this was a secondarily acquired canaliculops with punctal stenosis.6 Both anatomical and functional patency of the lacrimal system is important for a patient to be symptom free. The functional outcome in these cases is unknown. The current report describes two cases of congenital canaliculops with associated punctal agenesis