Lateral Canthus Research Articles

Re-evaluation of the orbicularis oculi muscle as revealed by the analysis of isolated muscle specimens.

This study aimed to clarify the origin, insertion, and subdivision of the orbicularis oculi in detail with in situ specimens, as well as with isolated muscle specimens from the superficial and deep aspects. The periorbital muscles in fifteen cadavers fixed with formalin were examined in situ and/or in isolated muscle specimens, and evaluate their actions. The orbicularis oculi arose via the nasoglabellar aponeurosis, which was observable in the deep aspect of isolated specimens as a rigid sheet of connective tissue in the middle of both orbits and adhered to the dorsum nasi in situ (100%). The two subdivisions of the orbicularis oculi were demarcated at the lateral angle of the eye and exhibited different insertions. The fascicles of the upper and lower halves of the inner part met each other at the lateral canthus and formed a shallow groove between them as observed in situ, and terminated via the lateral palpebral raphe on the deep aspect of the muscle to the temporal fascia. The fascicles of the upper and lower halves of the outer part extended over the orbital margin and intermingled with each other to disperse in the temporal subcutaneous tissue. The nasoglabellar aponeurosis was structurally characterized as the common origin of the periorbital muscles. The present study confirmed that the inner and outer parts of the orbicularis oculi are distinguished by the difference of lateral termination and interpreted as having different function on the palpebral movement in each.

Application of surface landmark positioning in assisting cone-beam CT scanning of temporomandibular joint

Objective: To quantitatively measure the spatial relationship between the temporomandibular joint (TMJ) and surface landmarks such as the tragus and lateral canthus using cone-beam CT (CBCT), as to provide guidance for accurate positioning of CBCT scanning of the TMJ. Methods: DICOM format data from 112 patients (35 males and 77 females with 224 TMJs) were included in this study. The patients were between 12 and 66 years old, with a mean age of (25.6±9.81) years and they underwent initial visits at the Department of Stomatology, The First Medical Center, Chinese PLA General Hospital. CBCT images were imported into Mimics Medical 21.0 software for three-dimensional reconstruction. The distance between selected surface landmarks and corresponding projection points on the same side of the TMJ were measured in both the sagittal and coronal planes. In the frontal view, the distance from the lateral canthus to the perpendicular line passing through the center of the condyle (dx); in the lateral view, the vertical distance from the horizontal line through the rear edge convex of tragus to the roof of glenoid fossa (dy1); the vertical distance from the horizontal line through the rear edge convex of tragus to sigmoid notch (dy2); the distance from the tragus to the perpendicular line through the center of the condyle (dz). The results were compared between different genders and age groups (adolescent group aged 12 to 18 years, 33 cases; adult group aged>18 years, 79 cases). To verify the reliability and stability of the body surface landmarks obtained in this study, a comparison was made between the use of scout view positioning and the auxiliary positioning method that utilizes body surface landmarks to capture the mandibular condyle in a small field of view CBCT of the TMJ (scout view group, 25 cases; surface landmark-assisted positioning group, with 25 cases aged 12-18 years and 25 cases older than 18 years, totaling 50 cases), with regard to the deviation distance from the central point of the field of view to the central point of the mandibular condyle. Results: A total of 112 patients with 224 TMJs were included in this study. In the frontal view, dx was (8.59±3.13) mm, with no significant difference between the left and right sides, between males and females (P>0.05). Notably, the dx in the adolescent group [(7.43±3.02) mm] was significantly smaller than that in the adult group [(9.07±3.06) mm] (t=-3.68, P<0.001). In the lateral view, dy1 was (14.80±3.90) mm, showing no significant difference between the left and right sides, males and females, or different age groups(P>0.05). Similarly, dy2 was (6.82±3.95) mm, with no significant differences between the left and right sides or between males and females(P>0.05). However, the dy2 in the adolescent group [(5.88±4.13) mm] was significantly smaller than that in the adult group [(7.22±3.83) mm] (t=-2.33, P=0.021). Regarding dz, the measurement was (11.73±3.16) mm, with no significant difference between the left and right sides, between males and females (P>0.05). Meanwhile, the dz in the adolescent group[(10.92±2.74) mm] was also significantly smaller than that in the adult group [(12.07±3.27) mm] (t=-2.52, P=0.012). The verification results showed that both positioning methods could fully display the TMJ. The eccentricity in the scout view group [(8.84±3.79) mm ]was slightly greater than that in the body surface landmark-assisted positioning group[ (6.50±2.88) mm], and the difference between the two groups was statistically significant (t=4.20, P=0.032). Conclusions: The TMJ can be accurately positioned using stable surface landmarks such as the tragus and lateral canthus for reference.

Role of Lower Eyelid Reconstruction in Complete Functional Rehabilitation

Objective: To present a case of reconstruction of a full-thickness lower eyelid defect.Case report: Male patient Y. aged 71 years was admitted to the Scientific Research Institute – Ochapovsky Regional Clinical Hospital No. 1 (Krasnodar, Russian Federation) with the diagnosis: cancer of skin of the lateral canthus of the left eye, T1N0M0, stage I, clinical group II. According to the medical history, the neoplasm was self-detected 5 years ago. Histology findings revealed micronodular basal cell carcinoma.After a general clinical examination, the patient underwent surgery to remove the neoplasm of the lower eyelid skin and lateral canthus and reconstruct the defect using a lateral infraorbital fat pad flap, local tissues, and a free autologous cartilage graft. The configuration of the soft tissues of the eyelid was restored. Soft tissue edema was not observed. The functional state of the lacrimal apparatus was fully preserved. The esthetics of the soft tissue was rehabilitated.Conclusions: Reconstruction in such esthetically significant area as the middle third of the face is associated with special requirements for graft formation and positioning. A gentle and functionally justified method for restoring the parameters of the tarsal plate, conjunctival sac, and lower eyelid skin ensures complete rehabilitation of patients and improves their quality of life.

Orbital Septum in Lateral Canthus

ABSTRACT Purpose To disclose the precise attachment site of the orbital septum in the lateral canthus. Methods Nine specimens of 7 Japanese cadavers aged 66 to 85 years at death were included. The attachment site of the orbital septum in the lateral canthus was grossly dissected. Two of the 9 specimens were exenterated and used to explore the anatomy from lateral and superior aspects, respectively. Results The orbital septum in the lateral canthus attached slightly lateral to the outer edge of the lateral commissure with the levator aponeurosis and the lower eyelid retractors in the upper and lower regions, respectively. In addition, the orbital septum attached to the arcus marginalis with regard to the orbital bone. Fat tissue occupied the space between the orbital septum and the lateral retinaculum. Conclusion The orbital septum in the lateral canthus attached around the lateral commissure and the orbital rim.

When to change needles during neuromodulator injections-An electron-microscopy investigation into needle tip deformation.

Neuromodulator injections are minimally invasive procedures performed across the globe. Despite their ubiquity, there is a dearth of information on whether and how needle tips used for neuromodulator procedures are deformed after repeated injections. We investigated the magnitude of needle tip deformation following sequential injection passes (3×, 5×, and 10×) during facial neuromodulator injections with three commonly used needle sizes (30G, 31G, and 32G). Neuromodulator was administered for four different aesthetic indications. Each collected needle was mounted and imaged in a Philips XL-30 Scanning electron microscope. Images were processed using ImageJ photo analysis software. Forty-five needle tips were investigated. When comparing the facial regions of interest, a statistically significant difference in deformation percentage was found when injecting 10× (p = 0.044) with greatest damage after injecting the glabella (38.4%), followed by lateral canthus (27.9%), forehead (27.5%), and midface (23.1%). Independent of facial region targeted, the mean percentage of needle deformation at 3× was 14.8%, at 5× 19.6%, and at 10× 29.2% with p < 0.001. Smaller needle size corresponded to smaller percentage of damage. Exchanging needles after more than five injection passes will minimize needle deformation and likely increase injection precision.

The Gliding Browlift: An Analysis of Outcomes and Maintenance of Lift in a Single Surgeon's Practice.

Efforts in browlifting longevity, desire for minimally invasive procedures, patient individualization, and minimization of complications led to the development of the gliding brow lift (GBL). The GBL has proven to be a successful, minimally invasive technique targeting brow elevation in combination with the hemostatic net. To evaluate maintenance of cutaneous brow elevation with the GBL technique at specific post-operative time points. A retrospective review was conducted of 63 patients (59 females; 4 males) who underwent a GBL by the senior author (JCG) between 2019 and 2022 for co-morbidities, maintenance of brow lift, and incidence of complications at four post-operative time points: 3, 6, 9, and 12 months. Pre- and postoperative photographs were analyzed at four anatomic locations: supraorbital rim, lateral canthus, mid pupil, and medial canthus. The cohort consisted of 59 female-only patients; male patients were excluded due to small sample size. The average age of 62.8 years old (SD ±7.01) and a mean BMI of 24. Only one patient required return to the operating room for hematoma evacuation; this was a result of a concomitant rhytidectomy and not involving the brow. All locations maintained a statistically significant lift (p<0.01). The most significant lift was at the lateral canthus (3.09 mm) and tail of the brow (2.74 mm) at 1 year post-operatively. The GBL is a successful innovation in aesthetic brow surgery. Depending on patient needs, it is an excellent choice for selective and long-term elevation of the lateral brow.

Mapping the localization of the facial artery and vein at the inferior border of the mandible for clinical applications.

To spatially map the position of the facial artery and vein along the inferior border of the mandible based on specific facial reference points. This cross-sectional study included 40 sides of 21 formalin-fixed cadaver heads (11 female, 10 male) with a mean age of 72.92 ± 11.72years. Superficial dissection was performed to visualize the facial artery and vein at the inferior border of the mandible (FA and FV). Measurements were taken from the FA and FV to various facial landmarks using a digital caliper and medical protractor. Statistical analysis was conducted using Shapiro-Wilk, independent sample t-tests, and paired sample t-tests. The mean distance between FA and FV was 6.20 ± 2.97mm. Distances from FA and FV to gnathion, oral commissure, nasal wing, lateral canthus, angle of mandible, intertragic notch, and Manson's point were determined, with no significant differences found between sides and genders (p > 0.05). The closest distances from FA and FV to the line between the intertragic notch and oral commissure were 38.63 ± 4.86mm and 37.78 ± 5.28mm, respectively. The angular measurements of FA and FV with inferior border of mandible were 61.45 ± 13.71 and 76.56 ± 10.17 degrees, respectively. The angle between intertragic notch, FA and oral commisure was 102.40 ± 11.12 degrees. The detailed measurements and analysis provided in this study aim to enhance the precision of surgical interventions involving the facial artery and vein. The practical localization methods proposed can assist in minimizing the risk of vascular injuries, improving outcomes in reconstructive and aesthetic procedures.

"Folding Fan Flap": A Novel and Dependable Surgical Technique for Crow's Feet Correction by Z-Plasty of Orbicularis Oculi Muscle.

The challenge of crow's feet surgical correction is to minimize the complication caused by orbicularis oculi muscle (OOM) resection while ensuring the operative effect. This study aims to propose a novel technique to solve this problem and evaluate its efficacy. From January 2022 to April 2024, all patients who received "Folding fan flap" in our institution were included. The outer third of the OOM below the lateral canthus was dissected and received Z-plasty to exchange width for length and reconstruct the muscle dynamics in a non-circular direction. Preoperative and postoperative smiling crow's feet were assessed by two independent physicians using the Lemperle wrinkle scale. At least six months after surgery, patient satisfaction with wrinkle correction, naturalness of facial expression, and local flattening was subjectively evaluated on a five-point scale. Complications including hematomas, incomplete eyelid closure, facial stiffness, and forehead numbness were recorded. A total of 32 patients (63 sides) were included with a mean follow-up of 13.9 ± 5.2 months. Postoperative assessments showed a significant reduction in Lemperle's score from 4.8 ± 0.4 to 1.5 ± 0.5 (P=0.000). Regarding the satisfaction of surgical outcomes and the naturalness of facial expressions, thirty patients (93.8%) were very satisfied. There were no severe complications such as hematomas and incomplete eyelid closure. Preliminary clinical studies demonstrated the efficacy of this technique in ensuring outcomes while preserving normal dynamic expressions. By Z-plasty of the outer circle of OOM, the muscle dynamic was successfully modified rather than eradicated. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

The application of basic SMAS rhytidectomy and comprehensive SMAS rhytidectomy.

Rhytidectomy has made great progress in the past 50 years, especially after the proposition of the concept of superficial musculoaponeurotic system (SMAS). Our previous research had classified SMAS rhytidectomy into basic SMAS rhytidectomy (B-SMAS) and comprehensive SMAS rhytidectomy (C-SMAS) according to whether the treatment of SMAS aponeurosis is combined with retaining ligament, fat pad, mimetic muscles, etc. The purpose of this paper is to compare the outcomes of the 2 methods. Through multicenter collaborative research, 21 cases of B-SMAS and 18 cases of C-SMAS were collected. Photographs were taken pre- and post-operation for each patient, and the facial width of the lateral canthus level (upper face), the alar base level (middle face), and the oral commissure level (lower face) were measured. We compared the statistics of upper, middle, and lower face pre- and post-B-SMAS and C-SMAS to assess the ramifications of each operation. We used preoperative measurements minus corresponding postoperative measurements of specific operation to assess which position would acquire superior improvements. We also recruited 3 professional plastic clinicians to rate the ramifications of specific positions and approaches after pre- and post-photo comparing. Through comprehensive analyzing, we compared the improvements between B-SMAS and C-SMAS to assess which method is more beneficial concerning facial rejuvenation. Both B-SMAS and C-SMAS would acquire optimal changing concerning facial width in middle and lower face after operation (P < .05). Two methods all harvested better width changing effects in middle and lower face than upper face (P < .05). However, C-SMAS acquired better effects in middle and lower face than B-SMAS (P < .05). Both B-SMAS and C-SMAS are beneficial to facial rejuvenation. The effects in middle and lower face are better than upper face. In addition, C-SMAS may be more effective than B-SMAS.

Interstitial brachytherapy for periocular nonmelanoma skin cancers: Impact on organ and function preservation

PurposeTo study the local control, toxicity, organ and functional preservation and cosmetic outcomes after interstitial brachytherapy for periocular nonmelanoma skin cancers. Methods and MaterialsPatients with skin cancers of upper and lower eyelid, medial and lateral canthus and the infra-orbital region treated with high dose rate (HDR) interstitial brachytherapy (ISBT) using 192-Iridium (192Ir) between December 2010 and July 2022 were included and data collected from a prospectively maintained database. Local control, survival outcomes, acute and late RTOG toxicity, functional and cosmetic outcomes were analysed. ResultsSixteen patients were included. Nine patients had lower eyelid tumors, 5 patients had tumors in canthi and two patients had skin tumor in the infra-orbital region. The median dose for definitive ISBT was 49 Gy in 14 fractions. After a median follow up of 73 months, all patients treated with definitive and adjuvant ISBT were locally controlled. Three of the four patients who received salvage ISBT for post-surgical failure had local recurrences and all were effectively managed with salvage re-surgery. Of the two deaths, none were disease related. Organ and function preservation was achieved in 15 (93.7 %) and 13 (81.2 %), respectively, with one patient being lost to follow up. Excellent, good, fair and poor cosmesis was seen in 6 (40 %) patients, 6 (40 %) patients, 2 (14 %) patients and 1(6 %) patient, respectively. ConclusionHDR-ISBT was safe and effective for skin tumors around the eye and resulted in excellent local control and survival outcomes preserving organ and function in majority of patients with good-excellent cosmesis.

Do Botulinum Toxin Injections for Upper Face Rejuvenation and Lateral Canthal Rhytids Have Unintended Effects on Tear Production?

To report the influence of botulinum toxin A (BoNTA) injections on basal tear production, as measured by Schirmer's test with anesthesia in patients seeking eyelid surgery. A retrospective cohort of patients requesting esthetic eyelid surgery reviewed by a single clinician between January 2021 to April 2024, assessed with Schirmer's test with anesthesia. Demographic data, history of BoNTA treatment in the periocular region, ocular surface disease index dry eye symptom frequency, and requirement for ocular lubricants were recorded. Patients with no history of BoNTA were designated as group 1. Patients with a positive recent history of periocular BoNTA were designated as group 2. The proportions of eyes with Schirmer's test with anesthesia (basal tear production) test result <5 mm ("low"), 5 to 9 mm ("borderline"), and ≥10 mm ("normal") were compared between groups. Seven hundred twenty-two eyes (361 patients) were assessed, of which 670 eyes (335 patients) met the inclusion criteria. Mean age was 55.1 (range, 17-93) years, with 71.3% female. Schirmer's data in group 1 were "low" at 32.9%, "borderline" at 26.4%, and "normal" at 40.7%. In contrast, group 2 had significantly lower results (P ≤ 0.05), with readings "low" at 48.3%, "borderline" at 26.7%, and "normal" at 25.0%. However, there were no significant differences between groups in ocular surface disease index symptom frequency scores or ocular lubricant requirements. Patients who had received BoNTA injections had significantly lower basal tear production compared with patients who had never received BoNTA. Esthetic BoNTA treatment may be associated with an unintended effect of decreased basal tear production and subsequent risk of dry eye.

Neurosurgical Importance on Temporal Branch of the Facial Nerve.

We aimed to determine anatomic features of the temporal branch (TB) of the facial nerve and its relation to various anatomic landmarks on the face in order to prevent damage in the surgical approach after head trauma or in planned neurosurgical interventions. Nine male cadavers preserved with formalin, were bilaterally dissected under a microscope at the laboratory of anatomy department of the university. The anatomical features of the branch and branching pattern of facial nerve and its relationships with adjacent neurovascular structures were evaluated using descriptive statistical data. The mean distance at the lateral canthus level between the far most anterior branch and far most posterior branch of the TB (APD) was 14.93 mm. The mean distance to the tragus of the entrance point of the TB to the orbicularis oculi muscle (ETT) was 74.72 mm. The mean distance between the origin point of the TB to the tragus (TT) was 24.50 mm. The angle between the far most anterior branch and far most posterior branch at the level of the lateral canthus (APA) was minimum 15°, maximum 40° and the mean value of APA was 24.61°. The number of branches originating from the TB (NB) were one to three branches which lay under the zygomatic arch and two to five branches upper the zygomatic arch, respectively. The number of anastomosis between the TB and zygomatic branch (AN) varies between 1 and 4; AN was found to be less intense in 10 sides and very intense in eight sides. The APA and APD value is mentioned for the first time in this study and nerve angle is considered to be as important as temporal branching in directing facial neurosurgical operations. We found that the unsafety zone may be exist for a 40 degree and 1.5 cm long area at the lateral canthus level, especially on the zygomatic arc where branching pattern is greater and 2.5 cm in front of the tragus. The data is significant for neurosurgeons to reach exactly this area without causing postoperative complications such as facial paralysis.

A Gaze into the Eyebrow Standards of Asian Versus Caucasian Women.

Eyebrow position affects perceived facial expression and youthfulness, and its modification is a key component of facial rejuvenation. This investigation aimed to assess the preferred vertical eyebrow position, apex location, and eyebrow shape in Caucasian and Asian individuals and to analyze gaze patterns during aesthetic judgment using eye-tracking technology. The study included 76 Asian and Caucasian volunteers with no medical background. Eye movements were captured with a Tobii Pro Nano eye-tracker. Participants viewed AI-generated images of Caucasian and Asian females with varied eyebrow positions (ratios 1:1.3 to 1:2.5), shapes (angles 8° to 20°), and apex positions. Aesthetic preferences were rated on a 5-point Likert scale. Eye-tracking metrics and aesthetic ratings were statistically analyzed using ANOVA and bivariate correlations. Both genders across ethnicities preferred a moderate eyebrow position ratio of 1:1.6. For eyebrow shapes, a 12° angle received the highest ratings, while extremes were less favored, indicating a preference for moderately curved eyebrows. The most appealing apex position was above the lateral canthus for Asians, and halfway between the lateral limbus and lateral canthus for Caucasians. Eye-tracking revealed longer fixations on unattractive features, suggesting more complex cognitive processing, while attractive features were processed more efficiently. The study revealed that aesthetic preferences for eyebrow features are influenced by both ethnic background and gender, with a general preference toward moderately curved eyebrows and subtle variations in preferred positions. These findings suggest a need for culturally sensitive approaches in facial aesthetic procedures and highlight the potential of eye-tracking technology to enhance surgical planning. Surgeons are advised to adopt a conservative, patient-centered approach when modifying eyebrow features, considering individual and cultural aesthetics to maximize patient satisfaction. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Dual-Plane Midface Lift Through Transoral and Transtemporal Approach.

The surge in the popularity of midface and temporal lifting procedures can be attributed to evolving social media trends and heightened patient expectations, particularly among younger individuals seeking "beautification" rather than traditional rejuvenation. Scarless techniques, such as transtemporal/transoral approaches, are increasingly preferred. This study aimed to combine the advantages of both superficial and deep dissection planes in midface and temporal lifting procedures. This retrospective study included 184 patients who underwent surgery using a dual-plane midface and temporal lift technique. Preoperative and postoperative assessments, including P1/P2 ratio calculations, were performed to evaluate volumetric distribution in the midface. The study cohort exhibited a significant improvement in the P1/P2 ratio postoperatively (p < 0.05), indicating successful volume redistribution. Complications, including hypoesthesia, bruising, and infection, were managed effectively. Minor asymmetries were observed, with revisions offered, but declined by the patient. This technique offers hidden incisions and reduces the risk of scar-related complications, making it suitable for patients seeking facial enhancement. Addressing the tear trough area and the lateral canthus provides comprehensive facial rejuvenation. The dual-plane approach facilitates both skin mobilization and volume shift, yielding favorable aesthetic outcomes. The dual-plane midface and temporal lift technique presented in this study offers a bi-vectoral approach to midfacial lifting, suitable for both beautification and rejuvenation goals. Despite the potential limitations, including infection risk, this method is an effective option for facial enhancement. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Quantitative orbital tightening for pain assessment using machine learning with DeepLabCut

Pain assessment in animal models is essential for understanding mechanisms underlying pathological pain and developing effective pain medicine. The grimace scale (GS), facial expression features in pain such as orbital tightening (OT), is a valuable measure for assessing pain in animal models. However, the classical grimace scale for pain assessment is labor-intensive, subject to subjectivity and inconsistency, and is not a quantitative measure. In the present study, we utilized machine learning with DeepLabCut to annotate the superior and inferior eyelid margins and the medial and lateral canthus of the eyes in animals’ video images. Based on the annotation, we quantified the eyelid distance and palpebral fissure width of the animals’ eyes so that the degree of OT in animals with pain could be measured and described quantitatively. We established criteria for the inclusion and exclusion of the annotated images for quantifying OT, and validated our quantitative grimace scale (qGS) in the mice with pain caused by capsaicin injections in the orofacial or hindpaw regions, the Nav1.8-ChR2 mice following orofacial noxious stimulation with laser light, and the oxaliplatin-treated mice following tactile stimulation with a von Frey filament. We showed that both the eyelid distance and the palpebral fissure width were shortened significantly in the animals in pain compared to the control animals without nociceptive stimulation. Collectively, the present study has established a quantitative orbital tightening for pain assessment in mice using DeepLabCut, providing a new tool for pain assessment in preclinical studies with mice.

Eye Temperature Measured with Infrared Thermography to Assess Stress Responses to Road Transport in Horses.

The aim of the present study was to investigate eye temperature modifications after road transport in athletic horses habituated to travel. Eight adult Italian saddle horses traveled 100 km and, two weeks later, 300 km. Eye temperature (ET), rectal temperature (RT) and serum cortisol concentration were assessed before (T1), after (T2) and 60 min (T3) after the road transport. ET was evaluated with infrared thermography (IRT) in three regions of interest: EL1 (medial canthus), EL2 (central cornea) and EL3 (lateral canthus). Two-way analysis of variance (ANOVA) for repeated measures showed statistically higher values at T2 and T3 for EL1 (p < 0.01), EL2 (p < 0.01) and EL3 (p < 0.01) following the 100 km journey. RT (p < 0.01) showed higher values at T2 and T3 after the 100 km journey and higher values at T2 (p < 0.01) following the 300 km journey. ET values were positively correlated with RT at T1, T2 and T3 following the 100 km journey and at T2 following the 300 km journey and positively correlated with serum cortisol concentration at T1, T2 and T3 following the 100 km journey and at T2 and T3 following the 300 km journey. Eye temperature monitoring with IRT allows quick and practical strategies to monitor an animal's physiological state and welfare during daily activities.

Comparison of Intense Pulsed Light Treatments including Upper Lid or Lateral Canthus in Patients of Meibomian Gland Dysfunction.

Background: To determine the differences in the effects of intense pulsed light (IPL) treatment when including the upper and lower lid or lateral canthus area in patients with meibomian gland dysfunction (MGD). Methods: Patients who underwent three IPL treatment sessions at 3-week intervals were divided into three groups according to the treatment sites: group A, lower lid; group B, upper and lower lids; and group C, lower lid and lateral canthal area. Before and after the IPL treatment sessions, we obtained the lid abnormality score (LAS), meibum expressibility (ME), meibum quality (MQ), lipid layer thickness (LLT), type I Schirmer test (ST), tear break-up time (TBUT) test, corneal fluorescein staining scores (CFSs), and Ocular Surface Disease Index (OSDI). Results: IPL treatment significantly improved LASs, ME, MQ, TBUT, CFS, and OSDI values in all groups. Differences in LAS values before and after IPL treatment were significantly greater in groups B and C than those in group A. Conclusions: IPL treatment encompassing the upper lid and lateral canthus together with the lower lid elicited additional improvement in patients with MGD. The additional effect on treating the lateral canthus was similar to the effect observed on the additional treatment of the upper lid.

Comparing clinical measures of near point of convergence and accommodation from the lateral canthus and browline in a paediatric and adolescent population.

Clinicians measure the near point of convergence (NPC) and the amplitude of accommodation (AA) from the spectacle plane, the bridge of the nose or the lateral canthus when assessing visual function. These values are compared to standard clinical criteria to diagnose vergence and accommodation deficits, despite varying reference points. This prospective study explored measuring relative to the spectacle plane and from the lateral canthus for NPC and monocular AA, and the resulting clinical implications of diagnosing visual deficits. Participants were seen by a single clinician for an eye examination. NPC was measured from the forehead and the lateral canthus of the right eye. Monocular AA was measured from the brow and the lateral canthus. Differences between measurements were analysed using non-parametric statistical tests including Wilcoxon Signed Rank, as well as linear regression and a linear mixed effects model to adjust for inter-eye correlation and repeated measures. Chi-square tests were used to assess differences in rates of abnormal findings. Data were collected from 70 participants (53% female, median age 13 [11-15] years). On average, measuring NPC from the lateral canthus yielded a value 1.8 cm higher than measuring from the forehead. Measuring AA from the lateral canthus resulted in an average difference of 1.5 cm compared to measuring from the brow. A total of 39% and 76% of subjects failed NPC compared to clinical norms when measured from the forehead or the lateral canthus, respectively, while 7% and 40% failed AA when measured from the brow or the lateral canthus, respectively. With the variable anatomy of the eye, it is imperative to account for the measurement point when assessing visual function. Measuring from the lateral canthus greatly increased the failure rates for NPC and AA compared with measuring from the forehead and brow, respectively.

Lateral canthal reconstruction for the treatment of macroblepharon/diamond eye conformation in dogs.

To introduce a novel surgical technique for treatment of macroblepharon and diamond eye conformation in dogs. Lateral canthal reconstruction was used in dogs with prominent eyelid malformations resulting in ocular surface disease. Lateral canthus was resected and new lateral canthus was created using a two-layer closure. This technique was performed either alone or in combination with additional procedure(s). Additionally, this technique was used to resect lateral canthal dermoid. One hundred and fifty-three eyes of 85 dogs were included in the study. Procedure was done for macroblepharon and/or lateral canthal entropion (149 eyes of 81 dogs) or for lateral canthal dermoid (four eyes of four dogs). Procedure was done either alone (n = 68 eyes) or in combination with additional procedure (n = 85 eyes). Favorable cosmetic outcome and client satisfaction was achieved in all dogs. Good to excellent functional outcome was recorded in all but 6 eyes of 4 dogs, which required additional surgery. Most common complications included slight undercorrection or overcorrection. Lateral canthal reconstruction is a simple yet effective surgical procedure for macroblepharon and/or lateral canthal entropion. If done early, it prevents development of secondary eyelid malformation ("pagoda defect") in giant breed dogs. If done after severe eyelid malformation has developed, combining this technique with concurrent pagoda resection is recommended to achieve ideal eyelid conformation. None.

Dynamic Measurement and Analysis of Upper Eyelid Changes Using Ultrasound Biomicroscopy

PurposeTo define the regular upper eyelid anatomy and their changes during dynamic motion using ultrasonographically depicted structures. DesignA cross-sectional study. MethodsHigh-resolution ultrasound biomicroscopy (50MHz) was performed on 84 upper eyelids of 42 healthy volunteers without evidence of eyelid conditions. The skin-orbicularis oculi complex (SOOC), levator aponeurosis, and Müller's muscle-conjunctival complex were imaged. The thickness of these structures was measured in primary gaze and downgaze positions. ResultsSOOC and levator aponeurosis thickness was bigger with eyes open than with eyes closed (p < 0.01). With eyes closed, the thickness of SOOC on the pupillary midline and levator aponeurosis was positively correlated with age (p < 0.05, p < 0.01, respectively), and the thickness of levator aponeurosis and SOOC on the pupil midline was also positively correlated with BMI index (p < 0.05). Similarly, SOOC thickness on the medial and lateral canthus line is also positively correlated with BMI index and age (p < 0.05, p < 0.01, respectively). As for the differences between genders, the mean thickness of SOOC and levator aponeurosis was statistically different (p < 0.05, respectively). The magnitude of levator aponeurosis thickness in men varied more than in women in different ocular positions (p < 0.05). All measurements had an intramethod between 0.624 and 0.792, and inter-rater ICC and intrarater ICC between 0.748 and 0.850. ConclusionsUltrasound biomicroscopy represents a noninvasive tool for the visualization of upper eyelid morphology. Expanding its application can help to understand the dynamics of upper eyelid physiological movement, aging, and disease research in different populations and evaluate surgical outcomes.