Lacrimal Secretion Research Articles

BMAL1 Deficiency Provokes Dry Mouth and Eyes by Down-regulating ITPR2/3

Secretory glands, responsible for tears and saliva production, play essential roles in maintaining ocular and oral well-being. Disruptions in gland secretion can arise from various factors, including rhythm disturbances associated with sleep disorders. However, the underlying mechanisms governing these disruptions remain largely unexplored. We demonstrate that BMAL1, a core component of the circadian system, plays a critical role in regulating secretory gland secretion. Loss of BMAL1 induces vacuolation and atrophy phenotypes in acinar cells, subsequently leading to cell apoptosis and gland hypofunction, but does not cause Sjogren's syndrome, which is characterized by localized inflammatory cell infiltration. Mechanically, BMAL1 directly modulates the transcription of ITPR2 and ITPR3, thereby altering the secretion of Lactoferrin and Lysozyme. Restoration of ITPR2 and ITPR3 expression in Bmal1-deficient rats effectively alleviated the symptoms of lacrimal and parotid glands secretory dysfunction and significantly reduced dry mouth and dry eye conditions in rhythm-disordered rats. These findings highlight the essential role of BMAL1 in regulating salivary and lacrimal gland secretion and suggest a novel therapeutic approach for treating dry mouth and dry eyes associated with rhythm disorders.

Organic cation transporter 1 in the lacrimal gland facilitates the entry of systemic drugs causing ocular surface toxicity

Many of the daily systemic medications (parenteral and oral) used to treat various diseases are known to cause ocular toxicities - leading to vision loss. How these medications gain entry into the eye despite the ocular barriers is an important question to be addressed. Various reports show almost 30–40 % of systemic drugs causing ocular toxicity are organic cation in nature. We hypothesize these systemic drugs (cations) are non-specifically recognized as endogenous substrates by organic cation transporter (OCT1) in the lacrimal gland, thereby facilitating its entry into the anterior eye segment. Therefore, we studied the expression and localization of OCT1 in the lacrimal gland of rabbits. Further, to prove our hypothesis, OCT1 substrates (known as well as predicted from our previous Artificial Intelligence study) were administered intravenously in the presence and absence of topically administered OCT1 blockers. Our findings show, OCT1 gene and protein expression in the lacrimal gland, with its localization in the terminal acinar cells. The tear levels of intravenously administered substrates decreased in the presence of topical OCT1 blockers, indicating – a) the entry of systemic drugs into the eye via lacrimal secretion and b) OCT1 in the lacrimal gland is involved in the drug transport (substrates) from blood to the eye. Though the role of transporters in toxicity is well-known, the current study opens a new avenue for understanding the role of transporters in ocular toxicity.

Effects of common eye diseases in children and their treatment measures on ocular surface homeostasis: A review.

Ocular surface homeostasis plays a vital role in maintaining of eye health. Dry eye disease is one of the prominent and typical manifestations of disruption of ocular surface homeostasis that leads to the worsening of ocular surface homeostasis that leads to the worsening of ocular surface disease when it interacts with other pathogenic factors. However, disruption in ocular surface homeostasis in children is often overlooked because of the current methods of assessing ocular surface homeostasis. This review summarizes the main factors affecting ocular surface homeostasis in children, with the aim of drawing the attention of clinicians to the disruption of ocular surface homeostasis in children when dealing with such diseases. Ocular surface homeostasis involves several interrelated components, each of which plays a nonnegligible role in ocular surface homeostasis. Unlike adults, children have a stronger lacrimal gland secretion capacity and milder symptoms when there is a slight disruption of the ocular surface homeostasis. In addition, children's expressive abilities were weaker. Therefore, dry eye in children is often ignored by doctors and parents, and clinicians should pay more attention to the protection of ocular surface homeostasis when treating children with these diseases. Therefore, there is a need for diagnostic criteria for dry eye disease specific to children.

Long-term high fructose intake reprograms the circadian transcriptome and disrupts homeostasis in mouse extra-orbital lacrimal glands

This study aims to explore the effects of long-term high fructose intake (LHFI) on the structure, functionality, and physiological homeostasis of mouse extra-orbital lacrimal glands (ELGs), a critical component of ocular health. Our findings reveal significant reprogramming of the circadian transcriptome in ELGs following LHFI, alongside the activation of specific inflammatory pathways, as well as metabolic and neural pathways. Notably, LHFI resulted in increased inflammatory infiltration, enhanced lipid deposition, and reduced nerve fiber density in ELGs compared to controls. Functional assessments indicated a marked reduction in lacrimal secretion following cholinergic stimulation in LHFI-treated mice, suggesting impaired gland function. Overall, our results suggest that LHFI disrupts lacrimal gland homeostasis, potentially leading to dry eye disease by altering its structure and secretory function. These insights underscore the profound impact of dietary choices on ocular health and highlight the need for strategies to mitigate these risks.

A Prospective Study of Dry Eye Syndrome among Patients with Type 2 Diabetes Mellitus

Introduction: Diabetes is one of the leading health related catastrophes the world has ever witnessed. It affects millions of people all over the world. The reduced corneal sensitivity favors the occurrence of dry eye syndrome (DES) by reducing the blink rate, by decreasing the reflex-induced lacrimal secretion and increasing evaporative tear loss. It affects millions of people all over the world. Objective: Assessment of incidence of dry eyes in type 2 diabetic patients. Methods: A prospective study was carried out to assess the presence of dry eyes and to investigate the relationship of retinopathy with dry eyes. After applying inclusion and exclusion criteria 50 diabetic patients who attended the out-patient department of the Department of Ophthalmology, Ad-din Akij Medical College, Khulna, Bangladesh from July to December 2023. After applying inclusion and exclusion criteria 50 diabetic patients who attended the out-patient department of the Department of Ophthalmology, were selected. Results: Out of 50 Diabetic patients, 29 had dry eyes. Mild form of dry eyes was most common (20%). Majority of the patients were between the ages of 40-60 years. There was no significant association of age, sex and duration of diabetes with incidence of dry eyes. Mild form of dry eyes was most common (20%). There was no significant association of age, sex and duration of diabetes with incidence of dry eyes. Abnormal tear break up time was abnormal in 32%. Abnormal Fluorescein staining was seen in 20% study subjects. Moderate non-proliferative diabetic retinopathy was significantly more common in diabetic patients with dry eyes. Conclusion: Examination of dry eyes should be an integral part of the assessment of diabetic eye disease so as to improve the patients comfort and to prevent or minimize further structural damage to the ocular surface.

The effect of cyclosporine a in pterygium surgery using fibrin glue.

To evaluate the effect of topical cyclosporine A (CsA) 0.05% in patients with pterygium surgery using fibrin glue (FG). Patients with primary nasal pterygium were retrospectically analyzed and categorized into two groups: Group 1 with 41 eyes from 38 patients as a control group and group 2 with 39 eyes from 36 patients who received topical CsA twice a day for 6months. Patients were assessed for recurrence rate, tear film parameters, side effects, and complications at postoperative intervals of 1-7days; 1st, 3rd, 6th and 12th months. The follow-up period was 1year. The two groups were age (p = 0.934) and sex (p = 0.996) matched. CsA drop was discontinued in one patient due to burning sensation and conjunctival hyperemia after 1 week. There was no statistically significant difference between the mean preoperative and postoperative 1st year Schirmer I and tear break-up time (TBUT) values in group 1 (p = 0.136; p = 0.069). Although the difference between the mean preoperative and postoperative 1st year TBUT values in group 2 was not statistically different (p = 0.249), Schirmer I results were higher postoperatively (p = 0.003). There was no statistically significant difference between preoperative Schirmer (p = 0.496), postoperative Schirmer (p = 0.661), preoperative TBUT (p = 0.240) and postoperative TBUT (p = 0.238) results of the two groups. Recurrence was observed in only one patient from group 1. No recurrent pterygium cases were observed in group 2. Schirmer I values were higher postoperatively in group 2; thus,topical CsA treatment may improve lacrimal secretion and be effective after pterygium surgery with FG.

The Role of Aquaporin 4 in Lacrimal Gland Ductal Fluid Secretion in Mice.

Earlier reports highlighted the predominant presence of aquaporin 4 (AQP4) in the duct cells of rabbit lacrimal glands (LGs). Whereas significant alterations in AQP4 mRNA levels have been observed in experimental dry eye and during pregnancy, the impact of AQP4 in LG ductal fluid production remains unclear. In our recent work, the role of AQP4 in LG ductal fluid secretion was investigated utilizing wild type (WT) and AQP4 knock out (KO) mice. Tear production was assessed in both WT and KO animals. Immunostaining was used to identify AQP4 protein. Duct segments were harvested from LGs of WT and KO mice. Fluid secretion and filtration permeability (Pf) were quantified using video-microscopy. Ductal tear production, elicited by a cell-permeable cAMP analogue (8-bromo cAMP), carbachol, vasoactive intestinal peptide (VIP), and phenylephrine (PHE), were assessed in both WT and KO ducts. A higher expression of AQP4 protein was noted in the duct cells from WT mice when compared to acinar cells. Pf did not show notable alterations between WT and AQP4 KO ducts. Carbachol elicited comparable secretory responses in ducts from both WT and KO animals. However, 8-bromo cAMP, VIP, and PHE stimulation resulted in decreased secretion in ducts from AQP4 KO LGs. Our findings underscore the functional relevance of AQP4 in the fluid production of mouse LG ducts. AQP4 seems to play different roles in fluid secretions elicited by different secretagogues. Specifically, cAMP-mediated, and adrenergic agonist-related secretions were reduced in AQP4 KO ducts.

Microemulsion as Novel Drug Delivery for Fungal Eye Infection

The cornea, orbit, and other ocular tissues may get infected by fungi. Ophthalmic mycoses, often known as ocular fungal infections, are a significant cause of morbidity and blindness. For fungus infections, a brand-new azole derivative has been authorized. New immunological techniques would also be beneficial in the future for enhancing patient outcomes. Treatment of ocular illnesses presents a significant barrier in terms of getting medications into the eyes using traditional drug delivery methods, such as solutions. The main barriers are those between blood and the eyes, between lachrymal fluid and the eyes, and between medication losses from the ocular surface brought on by lachrymal fluid secretion. To increase the bioavailability and lengthen the residence duration of medications administered topically to the eye, a variety of ocular drug delivery carriers have been developed. The microemulsion is created using the PHASE TITRATION METHOD. Due to the dual hydrophilic and lipophilic properties of microemulsions, the loaded medications can diffuse passively and become significantly partitioned in the varying lipophilic-hydrophilic ocular barrier. This abstract will provide details on the microemulsions used to treat fungal infections of the eyes.

Mucoadhesive, antioxidant, and lubricant catechol-functionalized poly(phosphobetaine) as biomaterial nanotherapeutics for treating ocular dryness.

Dry eye disease (DED) is associated with ocular hyperosmolarity and inflammation. The marketed topical eye drops for DED treatment often lack bioavailability and precorneal residence time. In this study, we investigated catechol-functionalized polyzwitterion p(MPC-co-DMA), composed of 2-methacryloyloxyethyl phosphorylcholine (MPC) and dopamine methacrylamide (DMA) monomers, as potential topical nanotherapeutics for DED. The copolymers were synthesized via random free-radical copolymerization, producing different proportions of catecholic functionalization. All as-prepared polymer compositions displayed good ocular biocompatibility. At a feeding ratio of 1:1, p(MPC1-co-DMA1) can facilitate a robust mucoadhesion via Michael addition and/or Schiff base reaction, thus prolonging ocular residence time after 4 days of topical instillation. The hydration lubrication of MPC and radical-scavenging DMA endow the nano-agent to ease tear-film hyperosmolarity and corneal inflammation. A single dose of p(MPC1-co-DMA1) (1mg/mL) after 4 days post-instillation can protect the cornea against reactive oxygen species, inhibiting cell apoptosis and the over-expression of pro-inflammatory factors (IL-6 and TNF-α). In clinical assessment, DED-induced rabbit eyes receiving p(MPC1-co-DMA1) could increase lacrimal fluid secretion by 5-fold higher than cyclosporine A. The catechol-functionalized polyzwitterion with enhanced lubricity, mucoadhesion, and anti-oxidation/anti-inflammation properties has shown high promise as a bioactive eye drop formulation for treating DED.

Analysis of the safety and effectiveness of endoscopic nasal dacryocystorhinostomy in the remedy of chronic dacryocystitis.

To estimate the safety and effectiveness of endoscopic nasal dacryocystorhinostomy in the remedy of chronic dacryocystitis. The clinical data of 105 subjects with chronic dacryocystitis enrolled into our hospital were analyzed retrospectively. The subjects were distinguished into nasal endoscopic group (endoscopic dacryocystorhinostomy; i.e., 51 cases) according to their surgical methods and external-route group (external-route dacryocystorhinostomy; i.e., 54 cases). The therapeutic effect, lacrimal gland secretion function, tear film stability, degree of epiphora, lacrimal passage patency, complications, and recurrence rate were contrasted between the 2 groups. The nasal endoscopic group exhibited a higher effective remedy rate (98.04%) compared with the external-route group (83.33%). Three months postoperation, both groups showed improvements in lacrimal gland secretion function and tear film stability, with the nasal endoscopic group demonstrating more significant enhancement in lacrimal gland secretion function than the external-route group. Six months postoperation, a reduction in the degree of epiphora was observed in both groups, with the nasal endoscopic group displaying a more pronounced decrease in epiphora severity and a higher lacrimal passage patency rate than the external-route group. Furthermore, the nasal endoscopic group experienced lower incidences of postoperative complications and recurrence rates. Endoscopic dacryocystorhinostomy is safe and effective in the remedy of chronic dacryocystitis.

Diversity of Thelazia spp. in domestic cattle from Romania: epidemiology and molecular diagnosis by a novel multiplex PCR

BackgroundThelaziosis is a neglected vector-borne disease caused by parasitic nematode worms of the genus Thelazia which affects various hosts. Limited attention has been given to ungulate-associated Thelazia species. Current diagnosis of thelaziosis and the identification/differentiation of species heavily relies on morphological features. Therefore, we conducted an epidemiological study in Romanian cattle, with the aim to obtain morphological and molecular data that can be used for species identification.MethodsThe eyes of 705 slaughtered cattle were sampled and subjected to morphological identification, morphometric analysis, and molecular characterization. PCR amplification and sequence analysis were performed based on the cytochromec oxidase subunit 1 (COI) gene. Statistical tests assessed the correlations between infection parameters and ecological or biogeographical factors. A novel PCR method was developed based on the consensus sequence from each species. Specific forward primers were designed for each of the three species, and a reverse primer (COIintR) was used for all reactions. A consensus thermal profile was established by gradient PCR amplification of each species separately.ResultsOf the sampled cattle, 19.3% were infected with Thelazia spp. Prevalence varied significantly with ecogeographical factors. A total of 585 Thelazia nematodes were recovered, with T. rhodesi being the most abundant, followed by T. skrjabini and T. gulosa. Morphometric and molecular analyses supported the morphological identification, yielding unique sequences for each species. From the 59 T. rhodesi specimens sequenced, 29 unique sequences were obtained, with a 99.1–99.85% nucleotide identity to the only other COI sequence present in GenBank®. All nine T. gulosa isolates were unique (99.37–100% nucleotide identity to other sequences), while T. skrjabini specimens displayed 98.47–100% nucleotide identity to the sole available sequence.ConclusionsBovine thelaziosis is prevalent in Romania, raising concerns for animal welfare and potential economic impacts. Infected cattle grazing alongside vulnerable wild ruminants, such as the European bison, may affect conservation efforts. Our newly developed multiplex PCR shows promise as a valuable surveillance tool, enabling the detection of occult infections in apparently healthy animals through lachrymal secretion testing.Graphical

THU262 Improvement Of Pharmacokinetic Properties Of Vasoactive Intestinal Peptide Through Backbone Modifications

Abstract Disclosure: M.S. Al Najar: None. A.M. Lipchik: None. Vasoactive Intestinal Peptide (VIP) is a 28 amino acid neuropeptide hormone that is a part of the glucagon/secretin family. VIP has myriad physiological functions, including incretin effects, immune modulation, corneal wound repairing, and lacrimal secretion. VIP executes these functions through activation of two B1 family of G-protein-coupled receptors, VPAC1 and VPAC2, leading to cAMP production. Previous research has demonstrated that VIP has immense therapeutic potential in treating many diseases including type 2 diabetes, cardiovascular disease, and autoimmune diseases such as rheumatoid arthritis, type 1 diabetes, and Crohn's disease. Although VIP has proven to be pharmacologically active in these diseases, its utility as a therapeutic is limited due to its short half-life in circulation (less than one minute) caused by proteolytic degradation. Previous efforts have been made to improve serum stability through peptide stapling using lactamization and olefin-metathesis. However, both strategies failed to increase the stability of VIP. Additional strategies are needed to improve serum stability of VIP. A potential alterative approach is the utilization of peptide backbone modifications to prevent proteolytic recognition and degradation. The introduction of unnatural amino acids and analogs such as N-methyl amino acids and peptoids into the VIP sequence alters the peptide bond by placement of a methyl group or a side chain on the amine. Here, we present a library of VIP analogs containing N-methyl amino acids and peptoid substitutions. The serum stability, structural conformation, and pharmacological activity of the VIP analog library was compared and tested against wild-type VIP. The incorporation of N-methyl amino acids or peptoid residues demonstrated significant improvement in stability in human serum. In addition, the VIP analogs maintained alpha-helical confirmation similar to wild-type VIP. Finally, the VIP analogs were shown to maintain pharmacological activity as VPAC1 agonist as measured by cAMP production and glucose-dependent insulin secretion. Together, these results display the incorporation of unnatural amino acids with modified backbones can improve pharmacokinetics while maintaining pharmacodynamics of VIP, allowing for the potential use of VIP as a therapeutic. Presentation: Thursday, June 15, 2023

Surgical Punctal Occlusion; Combined Lacrimal Canaliculi Cauterization and Punctal Suturing for Severe Dry Eye.

To evaluate the treatment outcome of surgical punctal occlusion with combined canaliculi ablation and punctal suturing in patients with severe dry eye. Eleven eyes of seven patients were diagnosed with severe dry eye with decreased lacrimal secretion and were refractory to treatment with various eye drops and/or had repeatedly experienced loss of punctal plugs, and continued to experience subjective symptoms received surgical punctal occlusion. In 20 puncta, lacrimal canaliculi ablation was performed along the entire length of the lacrimal canaliculus where a diathermy needle could be inserted. After resection of the annulus fibrosus in the peri-punctal area, tight cross-stitch suturing of the puncta was performed with 8-0 absorbent thread. Visual acuity, corneal staining score according to the area (A) and density (D) classification, and Schirmer tear test (STT); tear break up time (tBUT); and subjective symptoms assessed by the University of North Carolina (UNC) and Dry Eye Management Scale were compared before and one year after surgery. Recanalization occurred in 1/20 puncta (5.0% at month 5) in 1/11 eyes. Student's t-test showed significant improvement at one year compared with preoperative values for LogMAR value (P = 0.019), corneal staining score A (P = 0.00003) and D (P = 0.0003), STT (P = 0.004), and subjective symptoms (P = 0.015). No change was shown in tBUT and no serious adverse event occurred. This improved, minimally invasive surgical procedure has a low recanalization rate and achieves both objective and subjective improvements at one year.

Innovation in the Development of Synthetic and Natural Ocular Drug Delivery Systems for Eye Diseases Treatment: Focusing on Drug-Loaded Ocular Inserts, Contacts, and Intraocular Lenses

Nowadays, ocular drug delivery still remains a challenge, since the conventional dosage forms used for anterior and posterior ocular disease treatments, such as topical, systemic, and intraocular administration methods, present important limitations mainly related to the anatomical complexity of the eye. In particular, the blood-ocular barrier along with the corneal barrier, ocular surface, and lacrimal fluid secretion reduce the availability of the administered active compounds and their efficacy. These limitations have increased the need to develop safe and effective ocular delivery systems able to sustain the drug release in the interested ocular segment over time. In the last few years, thanks to the innovations in the materials and technologies employed, different ocular drug delivery systems have been developed. Therefore, this review aims to summarize the synthetic and natural drug-loaded ocular inserts, contacts, and intraocular lenses that have been recently developed, emphasizing the characteristics that make them promising for future ocular clinical applications.

Effectiveness of pharmacological interventions for Sjogren syndrome - A systematic review.

Sjogren's Syndrome (SS) is characterized by xeropthalmia and/or xerostomia. Treating the associated salivary gland hypofunction has been challenging to the clinicians. A variety of topical and systemic therapies have been tried to restore/stimulate the gland function or replace saliva reducing the symptoms of xerostomia and to avoid the problems of diminished salivary flow. Four search engines (PUBMED/Medline, EMBASE, Google Scholar and The Cochrane) were used in conducting a systematic review using the terms "Sjogren's syndrome" with the combination of other terms. To define these study acceptability criteria, we used PICO model (Population, Intervention, Control and Outcome) and study design technique. Out of 47 articles initially screened, 28 studies met our selection criteria. Included studies showed positive results with interventions such as pilocarpine, rituximab, and interferon-alpha (IFN-α) for enhancing salivary flow and lacrimal secretion in SS condition. One study showed promising results for combination of prednisone and hydroxychloroquine in SS, however dose of prednisone is recommended to be tapered. Another study demonstrated comparable effects of dehydroepiandrosterone and the placebo in alleviation of dry mouth symptoms (p=0.006). Therapeutic effects have been reported with LASER therapy. Pilocarpine was found to be highly beneficial whereas, rituximab and IFN-α were moderately effective in the reduction of hyposalivation in SS patient. Adverse events were common. Use of any alternative modalities for the management cannot be supported based on the current evidence; this demands more studies in future to be conducted staking into account adverse effects which might occur particularly with the pharmacological therapies. Key words:Sjogren's Syndrome, Xerostomia, Hyposalivation, Pilocarpine, Rituximab, Sialagogue.

Blueberry Leaf Extract Prevents Lacrimal Hyposecretion in Sjögren's Syndrome-like Model of Non-obese Diabetic Mice.

This study evaluated the effect of blueberry leaf hot water extract (BLEx) on Sjögren's syndrome (SS)-like lacrimal hyposecretion in male non-obese diabetic (NOD) mice. NOD or BALB/c mice were fed 1% BLEx or control (AIN-93G) for 2 weeks from the age of 4 to 6 weeks. Pilocarpine-induced tear volume was measured using a phenol red-impregnated thread. The lacrimal glands were evaluated histologically by H&E staining. The IL-1β and TNF-α levels in the lacrimal gland tissue were measured by ELISA. The mRNA expression levels of secretion-related proteins were measured by real-time PCR. LC3 I/II and arginase 1 expression levels were measured by western blot. After feeding with BLEx, pilocarpine-induced tear secretion in NOD mice was increased. In contrast, the mRNA expression levels of the cholinergic muscarinic M3 receptor, aquaporin 5, and ion channels related to lacrimal secretion were not changed by BLEx administration. In addition, the protein expression of arginase 1, which was recently reported to be involved in tear hyposecretion in NOD mice, was also not improved by BLEx administration. Although infiltration in the lacrimal gland of NOD mice was not decreased, the levels of TNF-α and the autophagy-related protein LC3 were significantly suppressed by BLEx treatment. BLEx treatment may ameliorate lacrimal hyposecretion in NOD mice by delaying the progression of autoimmune disease by suppressing autophagy in lacrimal glands.

Research progress on the pathogenesis of diabetes-related dry eye

In recent years, with the further understanding of medical circles on diabetic ocular complications, the ocular surface abnormalities of diabetes has drawn increasing concerns. Nearly 50% of diabetic patients suffer from dry eye symptoms. The main manifestations of diabetes related dry eye were abnormal lacrimal secretion, poor lacrimal stability, decreased corneal sensitivity, persistent corneal epithelial defect and even corneal ulcer, which were mainly related to the changes of structure and function of lacrimal gland, the decrease of goblet cells in conjunctiva, the abnormality of meibomian gland function and the degeneration of corneal nerve caused by diabetes. In this paper, we summarized and analyzed the recent research progress on the effect of diabetes on lacrimal film, corneal innervation and lacrimal gland innervation, and the correlation between oxidative stress, advanced glycation end products and diabetes-related dry eye, to explore the pathogenesis of diabetes-related dry eye and to provide reference for clinical diagnosis, treatment and research.

A Surgeon's Armamentarium for Ocular Management in Facial Paralysis: A Comprehensive Review.

To review the current management paradigm of the eye in patients with facial paralysis. A PubMed and Cochrane search was done with no date restrictions for English-language literature on facial synkinesis. The search terms used were "ocular," "facial," "synkinesis," "palsy," "neurotization," and various combinations of the terms. A total of 65 articles were included. Facial paralysis may result in devastating ocular sequelae. Therefore, assessment of the eye in facial paralysis is a critical component of patient management. Although the management should be individualized to the patient, the primary objective should include an ophthalmologic evaluation to implement measures to protect the ocular surface and preserve visual acuity. The degree of facial paralysis, lacrimal secretion, corneal sensation, and position of the eyelids should be assessed thoroughly. Patients with the anticipated recovery of facial nerve function may respond to more conservative temporizing measures to protect the ocular surface. Conversely, patients with expected prolonged paralysis should be appropriately identified as they will benefit from surgical reconstruction and rehabilitation of the periorbital complex. The majority of reconstructive measures within a facial surgeon's armamentarium augment coverage of the eye but are unable to restore blink. Eyelid reanimation restores the esthetic proportionality of the eye with blinking and reestablishes protective functions necessary for ocular preservation and function. Ocular preservation is the primary priority in the initial management of the patient with facial paralysis. An accurate assessment is a critical component in identifying the type of paralysis and developing an individualized treatment plan.

Current clinical application of lacrimal gland injection of botulinum toxin type A in inhibiting lacrimal secretion

Lacrimal gland injection of botulinum toxin type A inhibits the secretion of tears. As a new method to treat or alleviate the symptom of tears or epiphora, it has the characteristics of simple operation, definite curative effect, repeatable treatment and no irreversible complications. It provides an optional treatment scheme for many patients with refractory tears or epiphora. This article reviews the pharmacological characteristics of botulinum toxin type A, the mechanism of inhibiting tear secretion, the method and dose of lacrimal gland injection, indications and contraindications, clinical efficacy evaluation, complications, existing problems to be solved and prospects for reference.

History of the study of physiology and pathology of lacrimal secretion at the professor V.V. Volkov Ophthalmology Department at the S.M. Kirov Military Medical Academy

Вased on the analysis of literature data the information about the history of physiology and pathology of the lacrimal organs at the department of ophthalmology named after Professor V.V. Volkov of the Military Medical Academy is summarized and structured. The work is based on the historical-genetic method, including analysis of the literature and Internet resources represented by theses, abstracts, monographs and scientific articles. Materials from the libraries of the following institutions were used when writing the work: Helmholtz National Medical Research Center, Federal State Budgetary Educational Institution of Higher Education Kirov Military Medical Academy of the Russian Defense Ministry. The main works performed under each head of the chair which contributed to the development of national and world dacryology are shown. The work covers the period since the chair was founded in 1818 and headed by Josef Ernst Gruby up to the present day. Scientific works of the chair during the period of professors Boris L. Polyak and Veniamin V. Volkov leadership are analysed in detail. Modern methods and techniques used both for the therapeutic process and for teaching are described. The necessity of preserving traditions of the department and development of new directions is emphasized.