Orbital Fat Research Articles

Expression of Collagen XIII in Tissues of the Thyroid and Orbit With Relevance to Thyroid-Associated Ophthalmopathy.

Antibodies against collagen XIII have previously been identified in patients with active thyroid-associated ophthalmopathy (TAO). Although collagen XIII expression has been described in extraocular muscles and orbital fat, its detailed localization in extraocular and thyroid tissues and the connection to autoimmunity for collagen XIII remain unclear. Our objective was to map the potential targets for these antibodies in the tissues of the orbit and thyroid. We evaluated the expression of collagen XIII in human patient and mouse orbital and thyroid tissues with immunostainings and RT-qPCR using Col13a1-/- mice as negative controls. COL13A1 expression in Graves' disease and goiter thyroid samples was compared with TGF-β1 and TNF, and these were also studied in human thyroid epithelial cells and fibroblasts. Collagen XIII expression was found in the neuromuscular and myotendinous junctions of extraocular muscles, blood vessels of orbital connective tissue and fat and the thyroid, and in the thyroid epithelium. Thyroid expression was also seen in germinal centers in Graves' disease and in neoplastic epithelium. The expression of COL13A1 in goiter samples correlated with levels of TGF-B1. Upregulation of COL13A1 was reproduced in thyroid epithelial cells treated with TGF-β1. We mapped the expression of collagen XIII to various locations in the orbit, demonstrated its expression in the pathologies of the Graves' disease thyroid and confirmed the relationship between collagen XIII and TGF-β1. Altogether, these data add to our understanding of the targets of anti-collagen XIII autoantibodies in TAO.

Clinical efficacy and safety of composite non-cross-linked hyaluronic acid for treating tear trough-lower eyelid bag deformity.

Tear trough-eye bag deformities may appear in young Asian patients due to the weak support of their facial skeletons. For these patients with better periorbital skin elasticity, the injection may be more suitable than surgery for treating tear trough-lower eyelid bag deformity. Identify the clinical efficacy and safety of non-cross-linked HA in the treatment of tear trough-lower eyelid bag deformity. In this study, we analyzed pre- and postinjection photographs of 55 patients treated with non-cross-linked hyaluronic acid (HA) for tear trough-lower eyelid bag deformity. The mean [SD] scores of modified Goldberg score suggested that the most significant improvement of preoperative and postoperative scores was in tear trough depression, followed by infraorbital triangular depression, orbital fat prolapse, loss of skin elasticity, and skin transparency. Only transient localized complications were observed, including bruising, swelling, and erythema. There were no serious complications, such as skin necrosis or visual impairment. Our study confirmed the beneficial efficacy and minor complications of composite non-cross-linked HA for the treatment of tear trough-lower eyelid bag deformity.

The Origin and Course of the Blood Supply to the Lower Eyelid Orbital Fat: Anatomical Study and Clinical Significance.

The aim of this study is to investigate the origin and course of the orbital fat arterial supply in the lower eyelid using traditional anatomy and three-dimensional computed tomography (CT). Twenty-seven cadaver heads were infused with mercury sulfide contrast media through the ophthalmic artery, maxillary artery, transverse facial artery, and facial artery. CT images were obtained after contrast agent injection, three-dimensional CT scans were reconstructed, and the cadaver heads were dissected. Forty-five qualified hemifaces showed that the orbital fat arterial supply in the lower eyelid originates primarily from the inferomedial muscular trunk (IMT) of the ophthalmic artery and the orbital branch of the infraorbital artery. The medial branch of the IMT terminated at the medial fat pad (35.6%) or the orbital floor (64.4%). The lateral branch terminated at the inferior oblique (IO) muscle (28.9%) or the central and lateral fat pads (17.8%). In 53.3%, the lateral branch extended to the anterior part of the lateral fat pad and terminated in the orbital wall or the zygomaticoorbital foramina. The orbital branch of the infraorbital artery coursed between the orbital floor and the orbital fat, providing supply to the IO muscle, inferior rectus (IR) muscle, nasolacrimal duct, and orbital fat. This study elucidated the origin and course of the orbital fat arterial supply in the lower eyelid, which may help to avoid reducing the blood supply of the orbital fat pedicles during surgery. 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 .

Finite element model of ocular adduction with unconstrained globe translation

Details of the anatomy and behavior of the structures responsible for human eye movements have been extensively elaborated since the first modern biomechanical models were introduced. Based on these findings, a finite element model of human ocular adduction is developed based on connective anatomy and measured optic nerve (ON) properties, as well as active contractility of bilaminar extraocular muscles (EOMs), but incorporating the novel feature that globe translation is not otherwise constrained so that realistic kinematics can be simulated. Anatomy of the hemisymmetric model is defined by magnetic resonance imaging. The globe is modeled as suspended by anatomically realistic connective tissues, orbital fat, and contiguous ON. The model incorporates a material subroutine that implements active EOM contraction based on fiber twitch characteristics. Starting from the initial condition of 26° adduction, the medial rectus (MR) muscle was commanded to contract as the lateral rectus (LR) relaxed. We alternatively modeled absence or presence of orbital fat. During pursuit-like adduction from 26 to 32°, the globe translated 0.52 mm posteriorly and 0.1 mm medially with orbital fat present, but 1.2 mm posteriorly and 0.1 mm medially without fat. Maximum principal strains in the optic disk and peripapillary reached 0.05–0.06, and von-Mises stress 96 kPa. Tension in the MR orbital layer was ~ 24 g-force after 6° adduction, but only ~ 3 gm-f in the whole LR. This physiologically plausible simulation of EOM activation in an anatomically realistic globe suspensory system demonstrates that orbital connective tissues and fat are integral to the biomechanics of adduction, including loading by the ON.

Magnetic Resonance Imaging of Idiopathic Orbital Myositis.

To characterize the qualitative and quantitative features of idiopathic orbital myositis (IOM) on MRI. This was a multicenter retrospective study of patients with active IOM with MRI. Patients with incomplete clinical records, poor-quality or interval scans without active myositis, and specific orbital myositis (i.e., orbital myositis secondary to an identified condition) were excluded. An enlargement ratio was calculated by dividing the diameters of the affected extraocular muscle (EOM) by the contralateral unaffected EOM. Twenty-four patients (mean age: 44.4 ± 17.8 years-old, male: 11) between 2011 and 2022 were included. One case (4.2%) was pediatric (17 years old), and 6 cases presented with recurrence. Active IOM was characterized by fusiform EOM enlargement, high T2 signal, and contrast enhancement. Average maximal EOM diameters ranged from 4.6 to 7.7 mm (enlargement ratio: 1.4-2.2). Eighteen (75%) patients had single EOM involvement, most commonly the medial rectus. Other ipsilateral structures affected included focal orbital fat (16/24, 66.7%) and lacrimal gland (8/24, 33.3%). Contralateral changes in the EOM and/or lacrimal gland were observed in 7 patients (29.2%). Patients presenting with recurrence were likely to develop ongoing recurrent episodes ( p = 0.003). Various radiological patterns of involvement described including EOM enlargement, contrast enhancement, abnormal signal, and involvement of other orbital structures are indicative of active IOM. IOM remains a heterogeneous spectrum of acute and chronic clinico-radiological presentations. Inflammation may involve other ipsilateral or contralateral orbital structures or may be bilateral despite presenting clinically as unilateral disease. Quantitative measurements may have utility in differentiating IOM from other causes of orbital myositis.

Application of Intra-Orbital Septal Transfer of Lateral Orbital Septal Pedicled Fat Flap in the Treatment of Upper Eyelid Dents

Objective: To observe the clinical effect of intraorbital septal transfer of the lateral upper eyelid mass and orbital septum pedicled fat flap in the treatment of upper eyelid depression. Method: During the double eyelid surgery, the fat mass on the lateral side of the upper eyelid was exposed, a small incision was made on the outside of the orbital septum, the fat in the orbital septum was released, the blood vessels on the inside of the root of the fat mass were preserved, and the fat was sharply separated from the outside to the inside. The mass is trimmed into a strip-shaped pedunculated fat flap. A small lateral incision is made along the lateral side to separate the medial fat mass in the orbital septum. The separated fat flap is refilled into the orbital septum from the lateral incision and pulled to the medial side for fixation. Results: 33 patients were followed up for 3 to 12 months after surgery. Except for 1 patient with severe upper eyelid skin laxity who underwent surgical repair, the rest of the patients' upper eyelid depression was effectively relieved and the upper eyelids looked natural. The patients were satisfied with the surgical results. Conclusion: The intra-orbital septum transfer of the lateral upper eyelid mass and orbital septum pedicled fat flap is a simple and effective surgical method for the treatment of upper eyelid depression, with less pain and quick recovery. It is worth recommending in the treatment of upper eyelid depression.

Supraperiosteal fat repositioning with midface lift in lower eyelid blepharoplasty: an 18-year experience.

To assess the clinical outcomes of fat repositioning via supraperiosteal dissection with midface lift for correction of tear trough deformity in a large Asian patient population. Retrospectively review 1152 Asian patients who underwent fat repositioning to the supraperiosteal plane with a midface lift between 2005 and 2022. Surgical technique, postoperative course, and complications were recorded. At the 6-month postoperative follow-up, the degree of patient satisfaction was assessed. A total of 2304 eyes from 1152 patients with an average follow-up of 10 months. These procedures were performed using a transforniceal approach in 185 patients (16%) or a transcutaneous skin excision approach in 967 patients (84%). Among the patients who underwent the transcutaneous technique, seven individuals (0.6%) experienced effective treatment of lower lid ectropion through lateral tarsal strip procedures. Nine patients (0.7%) required revision surgery to address the remaining lateral fat pad due to inadequate lateral orbital fat excision during the initial procedure. At the 6-month follow-up, most patients reported a high level of satisfaction, with 800 patients (78%) expressing extreme satisfaction and 196 patients (19.1%) reporting satisfaction with the improvement in their appearance. No one reported facial numbness, lower eyelid or cheek paralysis, newly developed diplopia or granuloma formation. The procedure of fat repositioning involving supraperiosteal dissection and a midface lift, whether performed using a transforniceal approach or a transcutaneous skin excision approach, in lower eyelid blepharoplasty proves to be a secure and auspicious surgical technique for rectifying tear trough deformity and attaining a pleasing aesthetic outcome.

Surgical Correction of Depressed Scars After Upper Blepharoplasty: A Turnover Orbicularis-Septum Composite Flap Technique.

Depressed scarring is a common complication after incisional upper blepharoplasty and frequently contributes to patient dissatisfaction. Correcting this deformity presents a significant challenge for oculoplastic surgeons. This study aims to investigate the clinical effectiveness of employing the turnover orbicularis-septum composite flap technique in correcting depressed scars after double eyelid surgery. This is a retrospective study of 118 patients who underwent revision blepharoplasty with depressed scar from November 2020 to February 2023. During the revision procedure, the adhesions of the original scar were meticulously dissected, and the residual orbital fat was thoroughly released. The orbicularis-septum composite flap was then inverted downward and smoothly laid over the depressed scar area to address the tissue deficit. After surgery, patient satisfaction was evaluated by assessing the improvement of the depressed scars and the shape of the double eyelid folds. Follow-up assessments were conducted over a period of 6 to 24 months postoperatively. The results were judged as fully satisfied in 78 cases (66.1%), basically satisfied in 32 cases (27.1%), and unsatisfied in 8 cases (6.8%). Among the unsatisfied patients, 5 patients complained of eyelid fold shallow or disappear, and 3 patients complained of asymmetry. All patients exhibited varying degrees of improvement in the depressed scars. The turnover orbicularis-septum composite flap technique provides an effective approach for the treatment of depressed scars with a high satisfaction rate.

COMPARISON OF TEAR FILM BREAKUP PATTERN IN ACTIVE AND INACTIVE THYROID EYE DISEASE PATIENTS

Abstract
 Introduction & Objectives : Thyroid Eye Disease (TED) is an autoimmune inflammatory disease of the orbit that affects orbital fat, extraocular muscles, periocular tissue and lacrimal glands. TED activity can be assessed with a Clinical Activity Score (CAS) to identify active or inactive TED conditions. Dry Eye Diseases (DED) is one of the manifestations in patients with TED with a prevalence that varies from 27%-96%. The Asia Dry Eye Society (ADES) 2017 proposed a new concept for DED diagnosis and therapy, namely Tear Film Oriented Diagnosis (TFOD) and Tear Film Oriented Diagnosis Therapy (TFOT) with Tear Film Breakup Pattern (TBUP) examination. TBUP examination help in determine specific management of DED. The aim of this study is to determine the differences in TBUP in TED patients based on active and inactive.
 Methods : This is an analytical observational study with a cross-sectional design. The subjects were TED patients who came to the Cicendo Eye Hospital and met the inclusion criteria. The study was conducted at the National Eye Center of Cicendo Eye Hospital in April - June 2022. The data were analyzed with the Chi-Square Test.
 Results : This study was conducted on 23 patients or 46 eyes. This study found a statistically significant differences in TBUP features in active and inactive TED patients (p=0.0001). The most common features of TBUP was found in active TEDs was dimples (55%).
 Conclusion : There are differences of TBUP features in active and inactive TED patient.

COMPARISON OF TEAR FILM BREAKUP PATTERN IN ACTIVE AND INACTIVE THYROID EYE DISEASE PATIENTS

Introduction: Thyroid Eye Disease (TED) is an autoimmune inflammatory disease of the orbit that affects orbital fat, extraocular muscles, periocular tissue and lacrimal glands. TED activity can be assessed with a Clinical Activity Score (CAS) to identify active or inactive TED conditions. Dry Eye Diseases (DED) is one of the manifestations in patients with TED with a prevalence that varies from 27%-96%. The Asia Dry Eye Society (ADES) 2017 proposed a new concept for DED diagnosis and therapy, namely Tear Film Oriented Diagnosis (TFOD) and Tear Film Oriented Diagnosis Therapy (TFOT) with Tear Film Breakup Pattern (TBUP) examination. TBUP examination help in determine specific management of DED. The aim of this study is to determine the differences in TBUP in TED patients based on active and inactive. Methods: This is an analytical observational study with a cross-sectional design. The subjects were TED patients who came to the Cicendo Eye Hospital and met the inclusion criteria. The study was conducted at the National Eye Center of Cicendo Eye Hospital in April - June 2022. The data were analysed with the Chi-Square Test. Result: This study was conducted on 23 patients or 46 eyes. This study found a statistically significant differences in TBUP features in active and inactive TED patients (p=0.0001). The most common features of TBUP was found in active TEDs was dimples (55%). Conclusion: There are differences of TBUP features in active and inactive TED patient.

Complete Preservation of Orbital Fat by Restoration of Attenuated Orbital Septa Using an Acellular Dermal Matrix in Lower Blepharoplasty.

We hypothesized that application of acellular dermal matrix (ADM) over the orbital septum overlying the herniated orbital fat to tighten and strengthen the attenuated orbital septum in lower blepharoplasty would allow successful repositioning of the herniated orbital fat within the bony orbit. The author prospectively compared the cosmetic outcomes of lower blepharoplasty using ADM with standard blepharoplasty. We evaluated recurrence of eyelid bulging and tear trough deformity, volume of the lower periorbital region, and enophthalmos and eyelid droop 1 year after surgery. Twenty-two of the 24 enrolled patients completed the study. There was no significant difference in recurrence of eyelid bulging and tear trough deformity between standard blepharoplasty and blepharoplasty with ADM graft groups. In the standard blepharoplasty group, the volume of the lower periorbital region decreased significantly after surgery. In the blepharoplasty with ADM graft group, there was no significant change in the volume of the lower periorbital region after surgery. In the standard blepharoplasty group, there was no significant change in eyelid droop on either side after surgery. In the blepharoplasty with ADM graft group, the eyelid droop decreased significantly after surgery on the right side but showed no significant change on the left side. There was no significant change in enophthalmos after surgery for either group. This study demonstrated that ADM graft provided effective support for maintaining the replaced orbital fat in lower blepharoplasty. In the long-term, blepharoplasty with ADM graft might be effective in slowing development of age-related enophthalmos. 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 Pendulum Movement of Orbital Fat and Retro-Orbicularis Oculi Fat: A New Strategy for Correction of Sunken Eyelid Deformity in Revision Upper Blepharoplasty for Asian Patients.

With an increasing number of East Asians undergoing blepharoplasty, the number of patients with secondary upper eyelid deformities is increasing. The sunken eyelid deformity is a common deformity after upper blepharoplasty in Asians due to over-resection, retraction, or atrophy of the nasal and central orbital fat pads. Herein, we present a novel procedure, the pendulum movement of orbital fat and retro-orbicularis oculi fat ("POR" technique), for correction of sunken eyelid deformity in secondary Asian blepharoplasty. Patients who underwent secondary upper blepharoplasty with the POR technique by the senior author between January 2020 and October 2021 were identified retrospectively. Those with fewer than 6 months of follow-up were excluded. Patient charts and images were reviewed for demographic data, comorbidities, concomitant eyelid deformities, and postoperative complications. Pre- and postoperative aesthetics, including degree of sunken eyelid deformity, were assessed by two independent raters and by self-reported patient satisfaction. Forty-nine consecutive patients were identified, all of whom were female and had grade I or II sunken eyelid deformity. Median follow-up was 8 months. Concomitant deformities included high tarsal crease (N = 31 patients, 63.3%), ptosis (N = 13, 26.5%), and upper eyelid retraction (N = 5, 10.2%). Almost patients had improvement in their eyelid volume, and 95.9% had improvement in their aesthetic rating. Approximately 93.9% of patients were satisfied with the outcome. The POR technique is an effective technique for correction of sunken eyelid deformity and can be utilized in conjunction with other techniques during secondary blepharoplasty. 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 .

Three-dimensional soft tissue reconstruction and volume measurement used for the diagnosis of dysthyroid optic neuropathy.

Dysthyroid optic neuropathy (DON) leads to vision loss. This study aimed to investigate a new method that can directly evaluate the change in muscle cone inner volume (MCIV) and distinguish DON orbits from non-DONs. This study included 54 patients (108 orbits) who were diagnosed with thyroid eye disease and treated at the Beijing Tongren Hospital between December 2019 and September 2021. The extraocular muscle volume (EOMV), orbital fat volume (OFV), and bony orbit volume (BOV) of the patients were measured using three-dimensional reconstruction. MCIV was measured using artificially defined boundaries. The associations between these volumes and clinical indicators were studied, and the diagnostic efficacy of these volumes for DON was described using receiver operating characteristic (ROC) curves. The ROC curve showed that the area under the curve of MCIV/BOV (%) combined with EOMV/BOV (%) reached 0.862 (p < 0.001), with a sensitivity of 85.7% and a specificity of 76.1%. The combination of MCIV/BOV (%) and EOMV/BOV (%) is a good indicator for the diagnosis of DON, which aids in the early detection and intervention of DON.

Risk Factors for Orbital Invasion in Malignant Eyelid Tumors, Is Orbital Exenteration Still Necessary?

Basal cell carcinoma is the most common malignant skin tumor of the eyelids in Caucasians, followed by squamous cell carcinoma and sebaceous gland carcinoma. The primary treatment for these tumors is radical excision. In cases where malignant eyelid tumors are advanced and have invaded the orbit, orbital exenteration is necessary. In this retrospective study, we aimed to determine the correlation between the risk of orbital infiltration and various factors like tumor location, size, histological type, and patient age. This study revealed that tumors in multiple regions increased the risk of orbital infiltration by 3.75 times. Tumors with a diameter of 21–30 mm raised the likelihood of requiring exenteration by 15.5 times compared to smaller tumors (up to 10 mm). Age was also associated with the likelihood of orbital invasion in periocular tumors. Interestingly, no correlation was found between the histological type of the tumor and the risk of orbital infiltration. Notably, the conjunctiva of the eyeball was the most commonly infiltrated orbital structure, followed by the orbital fat. Timely treatment and well-planned procedures are crucial for patients with malignant periocular skin tumors to avoid multiple reoperations and the potential need for orbital exenteration.

Orbital Fat Herniation Through Inferior Orbital Fissure and Persistent Diplopia Caused by Facial Trauma.

Orbital fat herniation is often accompanied by orbital floor fractures. Furthermore, herniation through the inferior orbital fissure (IOF) is rare, and its pathophysiology remains largely unknown. Here, the authors report a case of a patient with IOF herniation and diplopia caused by orbital trauma. The patient was a 58-year-old male who had undergone reduction of a left zygomatic fracture 15 years previously; however, reduction of the lateral orbital wall displacement was not performed at that time. The patient presented with refractory diplopia following a sports-related orbital injury. Although no new facial fractures occurred, an asymmetric IOF herniation was observed in the left orbital fissure, which caused persistent diplopia. Surgical repair of the orbital fat herniation was performed 46 days after injury. Two months after the surgery, the herniation of the orbital fat and diplopia completely disappeared. Surgery for an IOF herniation should be considered when ocular symptoms persist after orbital trauma.

Whole-orbit radiomics: machine learning-based multi- and fused- region radiomics signatures for intravenous glucocorticoid response prediction in thyroid eye disease

BackgroundRadiomics analysis of orbital magnetic resonance imaging (MRI) shows preliminary potential for intravenous glucocorticoid (IVGC) response prediction of thyroid eye disease (TED). The current region of interest segmentation contains only a single organ as extraocular muscles (EOMs). It would be of great value to consider all orbital soft tissues and construct a better prediction model.MethodsIn this retrospective study, we enrolled 127 patients with TED that received 4·5 g IVGC therapy and had complete follow-up examinations. Pre-treatment orbital T2-weighted imaging (T2WI) was acquired for all subjects. Using multi-organ segmentation (MOS) strategy, we contoured the EOMs, lacrimal gland (LG), orbital fat (OF), and optic nerve (ON), respectively. By fused-organ segmentation (FOS), we contoured the aforementioned structures as a cohesive unit. Whole-orbit radiomics (WOR) models consisting of a multi-regional radiomics (MRR) model and a fused-regional radiomics (FRR) model were further constructed using six machine learning (ML) algorithms.ResultsThe support vector machine (SVM) classifier had the best performance on the MRR model (AUC = 0·961). The MRR model outperformed the single-regional radiomics (SRR) models (highest AUC = 0·766, XGBoost on EOMs, or LR on OF) and conventional semiquantitative imaging model (highest AUC = 0·760, NaiveBayes). The application of different ML algorithms for the comparison between the MRR model and the FRR model (highest AUC = 0·916, LR) led to different conclusions.ConclusionsThe WOR models achieved a satisfactory result in IVGC response prediction of TED. It would be beneficial to include more orbital structures and implement ML algorithms while constructing radiomics models. The selection of separate or overall segmentation of orbital soft tissues has not yet attained its final optimal result.

Adult stem cells in the eye: Identification, characterisation, and therapeutic application in ocular regeneration - A review.

Adult stem cells, present in various parts of the human body, are undifferentiated cells that can proliferate and differentiate to replace dying cells within tissues. Stem cells have specifically been identified in the cornea, trabecular meshwork, crystalline lens, iris, ciliary body, retina, choroid, sclera, conjunctiva, eyelid, lacrimal gland, and orbital fat. The identification of ocular stem cells broadens the potential therapeutic strategies for untreatable eye diseases. Currently, stem cell transplantation for corneal and conjunctival diseases remains the most common stem cell-based therapy in ocular clinical management. Lens epithelial stem cells have been applied in the treatment of paediatric cataracts. Several early-phase clinical trials for corneal and retinal regeneration using ocular stem cells are also underway. Extensive preclinical studies using ocular stem cells have been conducted, showing encouraging outcomes. Ocular stem cells currently demonstrate great promise in potential treatments of eye diseases. In this review, we focus on the identification, characterisation, and therapeutic application of adult stem cells in the eye.

Surgical correction of sunken upper eyelid with upper arcus marginalis release and precision fat distribution technique.

Sunken upper eyelids, characterized by hollowing in the upper orbital region, can contribute to an aged or fatigued appearance. We aim to report on the surgical technique and its effects, involving the release of the arcus marginalis of the upper eyelid and the precise distribution of orbital fat. From December 2021 to March 2023, a total of 84 eyelids from 42 patients who underwent surgical correction for sunken upper eyelids, utilizing the upper arcus marginalis release and precision fat distribution technique, were included in this study. Preoperative and postoperative sunken depths were measured and statistically analyzed. Aesthetic satisfaction was assessed through patient questionnaires. Preoperative and postoperative sunken depths measured 9.2 ± 2.2 mm and 5.9 ± 2.3 mm, respectively. The mean improvement was 3.3 mm, a change of statistical significance. Aesthetic outcomes and patient satisfaction yielded favorable results. No major complications were observed during the follow-up period. The upper arcus marginalis release and orbital fat distribution technique demonstrated favorable outcomes in correcting sunken upper eyelids. This procedure ensures stable placement of orbital fat at the deepest sunken point, resulting in aesthetically pleasing and enduring results. This technique serves as a valuable alternative for patients with moderate to severe sunken eyelids.

Comparative subcutaneous and submuscular implantation of an electroencephalography device for long term electroencephalographic monitoring in dogs.

Implantable electroencephalography (EEG) recording devices have been used for ultra-long-term epilepsy monitoring both in clinical and home settings in people. Objective and accurate seizure detection and recording at home could be of great benefit in diagnosis, management and research in canine idiopathic epilepsy (IE). Continuous EEG monitoring would allow accurate detection of seizure patterns, seizure cycles, and seizure frequency. An EEG acquisition system usable in an "out of clinic" setting could improve owner and veterinary compliance for EEG diagnostics and seizure management. Whether a subcutaneous ultra-long term EEG monitoring device designed for humans could be implanted in dogs. Cadaver study with 8 medium to large breed dogs. Comparatively using a subcutaneous and submuscular approach to implant the UNEEG SubQ-Implant in each dog. Positioning was controlled via CT post implantation and cranial measurements were taken. In four of the eight dogs a submuscular implantation without any complications was possible. Complications were close contact to the optic nerve in the first approaches, before the implantation angle was changed and in the smallest dog contact of the implant with the orbital fat body. Cranial measurements of less than 95 mm length proved to be too small for reliable implantation via this approach. The subcutaneous approach showed severe limitations and the implant was prone to dislocation. The UNEEQ SubQ-Implant can be implanted in dogs, via submuscular approach. CT imaging and cranial measurements should be taken prior to implantation.

Aliphatic and Olefinic Fat Suppression in the Orbit Using Polarity-altered Spectral and Spatial Selective Acquisition (PASTA) with Opposed Phase.

Fatty acid composition of the orbit makes it challenging to achieve complete fat suppression during orbit MR imaging. Implementation of a fat suppression technique capable of suppressing signals from saturated (aliphatic) and unsaturated (olefinic or protons at double-bonded carbon sites) fat would improve the visualization of an optical nerve. Furthermore, the ability to semi-quantify the fractions of aliphatic and olefinic fat may potentially provide valuable information in assessing orbit pathology. A phantom study was conducted on various oil samples on a clinical 3 Tesla scanner. The imaging protocol included three 2D fast spin echo (FSE) sequences: in-phase, polarity-altered spectral and spatial selective acquisition (PASTA), and a combination of PASTA with opposed phase in olefinic and aliphatic chemical shift. The results were validated against high-resolution 11.7T NMR and compared with images acquired with spectral attenuated inversion recovery (SPAIR) and chemical shift selective (CHESS) fat suppression techniques. In-vivo data were acquired on eight healthy subjects and were compared with the prior histological studies. PASTA with opposed phase achieved complete suppression of fat signals in the orbits and provided images of well-delineated optical nerves and muscles in all subjects. The olefinic fat fraction in the olive, walnut, and fish oil phantoms at 3T was found to be 5.0%, 11.2%, and 12.8%, respectively, whereas 11.7T NMR provides the following olefinic fat fractions: 6.0% for olive, 11.5% for walnut, and 12.6% for fish oils. For the in-vivo study, on average, olefinic fat accounted for 9.9% ± 3.8% of total fat while the aliphatic fat fraction was 90.1% ± 3.8%, in the normal orbits. We have introduced a new fat suppression technique using PASTA with opposed phase and applied it to human orbits. The purposed method achieves an excellent orbital fat suppression and the quantification of aliphatic and olefinic fat signals.