Search

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.

PurposeEffective visual perceptual processing is one of the many components of surgical competence. Human face identification is most efficient when viewed upright. However, it is not yet clear how this perception sensitivity impacts eyelid symmetry. This study investigates surgeons' and laypeople's accuracy and efficiency in perceiving eyelid asymmetry from different spatial perspectives.MethodsA prospective psychometric experiment was conducted where oculoplastic surgeons were recruited from the American Society of Ophthalmic Plastic and Reconstructive Surgery and the Brazilian Oculoplastic Surgery Society, and control participants were recruited via crowdsourcing (Amazon's Mechanical Turk). Standard illustrations of the human face with varying degrees of eyelid abnormality, laterality, gender and rotation were presented to participants who were asked to judge whether the eyelids were symmetric or asymmetric.ResultsThe survey was completed by 75 oculoplastic surgeons (49.33% male; mean age of 46.9±10.7) and 192 lay individuals (54.6% male; mean age 34.6±11.3 years). Among oculoplastic surgeons, deviation from upright was significantly associated with increased reaction time and decreased proportion correct (OR per 45° for peak 0.68, 95% CI 0.60 to 0.77, p

Erdheim-Chester disease (ECD) is an exceedingly rare non-Langerhans cell CD68+ CD1a- S100- histiocytic multi-organ disease. Diagnosis of ECD is often delayed due to non-specific radiographic findings and heterogeneous lesional tissue. Increasingly, the role of genomic alterations is being recognized for both diagnosis and treatment of ECD. More than half of ECD patients harbor the BRAFV600E mutation. Evaluation for this mutation be can falsely negative on immunohistochemical staining and confirmation with molecular analyses is recommended. We present a case of the 44 year-old male with BRAFV600E-positive ECD treated successfully with steroids followed by single-agent dabrafenib.

PurposeTo assess whether transcutaneous retrobulbar amphotericin B injections (TRAMB) reduce exenteration rate without increasing mortality in rhino-orbital-cerebral mucormycosis (ROCM).MethodsIn this retrospective case-control study, 46 patients (51 eyes) with biopsy-proven ROCM were evaluated at 9 tertiary care institutions from 1998 to 2021. Patients were stratified by radiographic evidence of local orbital versus extensive involvement at presentation. Extensive involvement was defined by MRI or CT evidence of abnormal or loss of contrast enhancement of the orbital apex with or without cavernous sinus, bilateral orbital, or intracranial extension. Cases (+TRAMB) received TRAMB as adjunctive therapy while controls (-TRAMB) did not. Patient survival, globe survival, and vision/motility loss were compared between +TRAMB and -TRAMB groups. A generalized linear mixed effects model including demographic and clinical covariates was used to evaluate the impact of TRAMB on orbital exenteration and disease-specific mortality.ResultsAmong eyes with local orbital involvement, exenteration was significantly lower in the +TRAMB group (1/8) versus -TRAMB (8/14) (p = 0.04). No significant difference in mortality was observed between the ±TRAMB groups. Among eyes with extensive involvement, there was no significant difference in exenteration or mortality rates between the ±TRAMB groups. Across all eyes, the number of TRAMB injections correlated with a statistically significant decreased rate of exenteration (p = 0.048); there was no correlation with mortality.ConclusionsPatients with ROCM with local orbital involvement treated with adjunctive TRAMB demonstrated a lower exenteration rate and no increased risk of mortality. For extensive involvement, adjunctive TRAMB does not improve or worsen these outcomes.

A simple method of demonstrating apparent weightlessness in free fall is described. The Apollo 15 hammer and feather drop experiment can be recreated in the classroom using a book to shield the feather from air resistance. Plastic toys and a feather thrown together in a plastic bottle can be used to recreate an apparent weightless environment close to the surface of the Earth. Since the bottle follows a parabolic trajectory, the objects within also follow a parabolic path and are seen to float as if in a space ship in orbit around the Earth. This demonstration is useful for demonstrating to students that apparent weightlessness is not confined to outer space. The use of toy fish in the experiments makes a connection with the neutral buoyancy training of astronauts. The experiments also exemplify Newton's second law that force is mass times acceleration. [ABSTRACT FROM AUTHOR]

Copyright of HNO is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

ABSTRACT To explore the diagnostic and therapeutic strategies of chronic invasive fungal sinusitis involving the skull base or orbit based on the background of multidisciplinary team discussion and to provide a basis for clinical practice. The clinical data of five patients with chronic invasive fungal sinusitis involving the skull base or orbit admitted to the Department of Otorhinolaryngology, Head and Neck Surgery of Drum Tower Hospital affiliated with Nanjing University School of Medicine from July 2017 to February 2024, were retrospectively analysed. The diagnosis and treatment strategies were all formulated after the MDT discussion. Nasal endoscopic surgery dominated the treatment protocol. Surgery was completed while ensuring the integrity of the dura mater or orbital periosteum. During surgery, we remove the lesion as thoroughly as possible and open the sinuses to improve their drainage function. The efficacy of the surgery was comprehensively analysed in the postoperative period. None of the five patients had serious complications such as ocular motor or visual dysfunction, cerebrospinal fluid leakage or intracranial infection after surgery. Four of them were cured after comprehensive treatment and had no recurrence after 5–84 months of follow‐up; one case had a wider range of lesions, but the patient did not follow the recommended antifungal treatment after surgery and had a recurrence 5 months after surgery; after the recurrence, the patient underwent a second endoscopic surgery and actively cooperated with the antifungal treatment, there were no complications after the second surgery and there was no recurrence after 78 months of follow‐up. For patients with chronic invasive fungal sinusitis involving the skull base or orbits, the diagnosis and treatment plan are formulated through MDT discussion before surgery, and the lesions are resected with the assistance of image navigation and the plasma system to protect the natural barrier of the dura mater or orbital periosteum from being breached, so as to achieve the purpose of removing the lesions and clearing the sinus drainage, and then supplemented with antifungal treatment. In this way, we can achieve satisfactory therapeutic effects while reducing nose–brain and nose–eye complications and improving the prognosis. [ABSTRACT FROM AUTHOR]

PurposeMethodsResultsConclusionTo describe the clinical presentation, management, and outcomes of orbital and adnexal rhabdomyosarcoma (RMS) in an Asian-Indian cohort and analyze the factors predictive of outcomes.Retrospective interventional case series of 54 patients of histopathology-proven RMSThe mean age of presentation with RMS was 10 years (median, 7 years; range, <1–54 years). The most common tumor location was the superonasal quadrant (n = 21, 39%). Extensions beyond the orbit into the sinuses, temporal fossa, and brain were seen in 15 (28%), 3 (6%), and 8 (15%), respectively. First-line treatment modalities included a combination of surgical debulking, chemotherapy, and external beam radiotherapy in 20 (37%) patients; chemotherapy and radiation in 20 (37%); complete surgical excision and chemotherapy in 3 (6%); orbital exenteration, chemotherapy, and external beam radiotherapy in 1 (2%); chemotherapy alone in 1 (2%) patient, and 9 (17%) patients were lost to follow up. By Intergroup Rhabdomyosarcoma Study Group (IRSG) grouping, tumors belonged to groups I (n = 2,4%), II (n = 13, 29%), and III (n = 30, 67%). Kaplan-Meier survival estimates for tumor recurrence, lymph node metastasis, systemic metastasis, and death (n = 45) were 84%, 82%, 95%, and 95% at 1 year, 69%, 76%, 81%, and 77% at 5 years, 69%, 76%, 81%, and 77% at 10 years, respectively. On multivariate regression, age >18 years was found to have a significantly increased risk of locoregional LN metastasis (p = 0.005).Despite aggressive treatment modalities, the 5–year disease-specific survival rate was 77% in Asian-Indian cohort. Age > 18 years at presentation was associated with a poorer prognosis. [ABSTRACT FROM AUTHOR]

In this study, we aimed to follow up on the surprising increase in the incidence of orbital subperiosteal abscesses (SPA) reported in the Iranian pediatric population in the post-COVID era. Pediatric patients (≤ 18 years old) diagnosed with orbital SPA following acute sinusitis who were hospitalized between October 1st, 2023, and March 31st, 2024 in Farabi Eye Hospital, Tehran, Iran, were included. Demographic, clinical, microbiologic, and radiological characteristics of patients were reviewed. During the 6-month study period, 39 patients were admitted to our tertiary referral hospital. The average age of patients was 7.29 ± 4.13 years and 30 patients (76.92%) were male. The ethmoid sinus was involved in 100% of patients, and SPA involvement was in the medial wall in 27 patients (69.23%). The mean volume of SPA was 1.45 ± 1.77 cm3. Nineteen patients (48.72%) underwent surgical interventions, however, 20 patients (51.28%) received only medical treatment. The best corrected visual acuity of patients increased from 0.63 (0.20 LogMAR) on the first day of admission to 0.84 (0.07 LogMAR) according to the Snellen chart in the first month after treatment. It seems that the outbreak of orbital SPA in the Iranian children population in the post-COVID era is an increasing trend. [ABSTRACT FROM AUTHOR]

Introduction: The morphological characteristics of eyes in fishes are highly diverse and have evolved to meet the specific visual requirements as per their habitats. These morphological features of eyes are important for researchers and ecologists. The dusky spinefoot (Siganus luridus) is a tropical teleost fish with a laterally flattened body which lives in the Mediterranean Sea. Currently, there are no histological data relating to the Siganus luridus eye. Methods: In this study, the morphology of the Siganus luridus eye was examined to enhance our understanding of its structure and its relationship to fish ecology. Detailed gross and microscopic features were recorded using light and scanning microscopy. Results: The key observations describe the main structural features of the eye of Siganus luridus, specifically, the diameter of the orbit, architecture of three tunics of eye and detailed lens description. The choroid was divided into four layers, and had a rete mirabile, consisting of numerous small blood vessels in the choroidal gland. The tapetum lucidum was observed, which is interesting since Siganus luridus is herbivore and herbivores typically lack a tapetum lucidum. Discussion: These observations shed new light on the intricate eye structure of Siganus luridus and provide valuable insights into its visual abilities and adaptations to the aquatic environment and feeding behavior. [ABSTRACT FROM AUTHOR]

Purpose: The posterior orbit is a confined space, harbouring neurovascular structures, frequently distorted by tumours. Image-guided navigation (IGN) has the potential to allow accurate localisation of these lesions and structures, reducing collateral damage whilst achieving surgical objectives. Methods: We assessed the feasibility, effectiveness and safety of using an electromagnetic IGN for posterior orbital tumour surgery via a comparative cohort study. Outcomes from cases performed with IGN were compared with a retrospective cohort of similar cases performed without IGN, presenting a descriptive and statistical comparative analysis. Results: Both groups were similar in mean age, gender and tumour characteristics. IGN set-up and registration were consistently achieved without significant workflow disruption. In the IGN group, fewer lateral orbitotomies (6.7% IGN, 46% non-IGN), and more transcutaneous lid and transconjunctival incisions (93% IGN, 53% non-IGN) were performed (p =.009). The surgical objective was achieved in 100% of IGN cases, with no need for revision surgery (vs 23% revision surgery in non-IGN, p =.005). There was no statistically significant difference in surgical complications. Conclusion: The use of IGN was feasible and integrated into the orbital surgery workflow to achieve surgical objectives more consistently and allowed the use of minimal access approaches. Future multicentre comparative studies are needed to explore the potential of this technology further. [ABSTRACT FROM AUTHOR]

Congenital opticmeningoceles were recently described as intraorbital optic nerve cystic lesions, in which neural tissue is found to be part of the lining of the lesion. We describe the case of an eleven-month-old patient with a right opticmeningocele, followed through seven years. He presented with proptosis and hypotropia since birth and imaging exams disclosed an intraconal cystic lesion. A needle puncture revealed a fluid characteristic of cerebrospinal fluid. Surgical drainage performed through a lid crease approach resulted in recurrence of the proptosis. Surgical excision of the capsule finally was definitive, and pathology revealed an epithelial-lined capsule. Eight months after the capsule excision, a strabismus surgery was performed to improve the right hypotropia. Although visual prognosis of opticmeningoceles is poor, a good cosmetic result can be obtained with a multidisciplinary approach involving orbit and strabismus surgeons. The complete capsule excision is believed to be the preferable surgical option for permanently treating the proptosis once needle puncture and cyst drainage are associated with recurrence. The orbital access for approaching the lesion depends on the location of the cyst and should provide wide exposure to avoid new surgical procedures in young patients. [ABSTRACT FROM AUTHOR]

Purpose: Orbital rhabdomyosarcoma is a rare soft tissue sarcoma in childhood but with a good prognosis. Treatment usually includes surgery, chemotherapy, and radiotherapy. This study aimed to evaluate long-term alterations in teeth and cranial bones in children, adolescents, and young adults after oncologic treatment for childhood orbital rhabdomyosarcoma. Method: This was a cross-sectional study that evaluated patients treated for orbital rhabdomyosarcoma between 1988 and 2011. Demographic, clinical, and treatment data were collected during the study period; also, panoramic radiographs, cephalometric study, and photographs of the face were taken. Results: Eight long-term survivors were studied. Of those, 50% were male, 75% had less than 5 years of treatment, and 88% had only one of the orbits affected by the tumor. Regarding treatment, 50% received 50.4 Gy of radiotherapy in the orbit; the chemotherapy included vincristine, actinomycin D, and cyclophosphamide in 75% of the cases and also ifosfamide and etoposide in 25%. The children presented craniofacial alterations, mainly when radiotherapy occurred between 0 and 5 years old (p = 0.01). The mandibles also showed dental alterations, probably due to chemotherapy. Conclusion: In conclusion, orbital RMS patients treated with chemoradiotherapy, important dental, and facial bone alterations were found. The most significant were in the maxilla and close to the irradiation field. Dental and mandibular bone alterations were also found, indicating the probable chemotherapy action, as this region was not included in the irradiation field. [ABSTRACT FROM AUTHOR]

The orbital cavity is a subject of interest for various specialists, and achieving optimal outcomes requires comprehensive, multidisciplinary management. This study aims to report 10 years of experience in the preoperative, surgical, and postoperative care of patients with orbital lesions, examining their clinical, radiological, and anatomopathological features and outcomes. A retrospective review of 125 patients who underwent surgical treatment for intraorbital masses between January 2012 and December 2021 was performed. Outcome measures included postoperative diplopia, exophthalmos, decimal visual acuity, eyeball position, ocular motility, operative time, complications, and aesthetic results. A total of 107 patients were included. All cases were discussed with a neuroradiologist to determine the best therapeutic approach based on preoperative imaging. Preoperative diplopia was linked to extraconal (p = 0.03) and anterior (p = 0.001) lesions, and exophthalmos and visual acuity deterioration were associated with intraconal (p = 0.02; p = 0.03) and retrobulbar (p = 0.001; p = 0.02) lesions. Complications (11.2%) included diplopia, worsened visual acuity, postoperative blepharoptosis, and postoperative ectropion. Of the patients, 80.4% reported an "excellent" aesthetic outcome. This study underscores the importance of a multidisciplinary approach based on a thorough analysis of preoperative imaging. Periorbital approaches tailored to the lesion's three-dimensional location enables safe access to most intraorbital lesions, resulting in minimal complications and good aesthetic results. [ABSTRACT FROM AUTHOR]

Copyright of GeSec: Revista de Gestao e Secretariado is the property of Sindicato das Secretarias e Secretarios do Estado de Sao Paulo (SINSESP) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

PurposeMethodsResultsConclusionOrbital/periorbital tuberculosis (TB) is an uncommon manifestation of extrapulmonary TB, presenting diagnostic challenges due to its varied clinical features that can mimic other diseases. This report aims to present a rare case of periorbital TB in a young man.Case report.A 36-year-old man presented with painless left periorbital swelling and discharge following facial trauma. Despite initial treatment with antibiotics elsewhere, symptoms persisted. Imaging revealed a periorbital abscess with adjacent bone involvement. Microbiologic studies demonstrated Mycobacterium tuberculosis complex growth, confirming TB. There was no evidence of systemic TB. The patient received anti-tuberculosis therapy. At the 8-month follow-up, he remained symptom-free.Orbital/periorbital TB, although rare, should be taken into consideration in regions with high TB prevalence when dealing with chronic, non-resolving periorbital lesions. Advanced imaging and molecular diagnostics play crucial roles in confirming the diagnosis, especially given the low sensitivity of traditional culture methods for extrapulmonary TB. [ABSTRACT FROM AUTHOR]

PurposeMethodsResultsConclusionTo investigate the prevalence of fatty infiltration in normal orbits using magnetic resonance imaging (MRI) and its impact on muscle diameters.A retrospective analysis was conducted on normal orbits in patients who underwent coronal T1-weighted MRI. Fatty infiltration was defined by a hyperintense signal within the extraocular muscle. Fatty infiltration area was calculated by dividing the cross-sectional fat area by the sum of the muscle and fat area in the coronal plane. Muscle diameters were measured perpendicular to the muscle belly at their maximum and the mean diameters of the infiltrated muscles were compared with the non-infiltrated muscles.Seventy-six orbits from 76 participants with a mean age of 55.7 ± 18 years were included. Fatty infiltration in at least one muscle was seen in 57 (75%) of participants. When infiltration was present, inferior rectus was most commonly involved (98%). The area of fatty infiltration ranged from 6% to 42%, with 5 participants in the <10% group, 36 in the 10–20% group, 20 in the 20–30% group, 9 in the 30–40% group and 2 in the 40–50% group. Participants with fatty infiltration were significantly older (mean 61 ± 15 years vs 40 ± 16 years, p < .01) and had a higher proportion of males (56% vs 16%, p < .01). No significant difference in muscle diameters were found between infiltrated and healthy muscles.Fatty infiltration of the extraocular muscles is a reasonably common finding in normal orbits, most commonly involves the inferior rectus muscle and is associated with increasing age. [ABSTRACT FROM AUTHOR]

Invasive breast cancer, no special type, is the most frequent subtype of breast malignancy encountered as compared to secondary breast cancer. The most common tumors metastasizing to the breast include lymphoma and melanoma. Rhabdomyosarcoma (RMS) is a common soft-tissue neoplasm in the paediatric population, often seen in regions such as the head and neck, genitourinary system, trunk, and extremities. While metastatic RMS to the breast is uncommon, it tends to occur primarily in adolescent girls, with the alveolar variant being the most frequently encountered. In this case presentation, we describe the unique instance of a 17-year-old girl admitted to the hospital with quadriplegia which on initial clinical evaluation was diagnosed as disseminated tuberculosis involving the spine (Pott's spine), but on further cytologic and histopathologic assessment revealed the unexpected diagnosis of rhabdomyosarcoma. This case draws attention to the unusual occurrence of rhabdomyosarcoma metastasis to bilateral breasts, that to with an embryonal morphology, and underscores the challenge of identifying the primary site of this rare manifestation. [ABSTRACT FROM AUTHOR]

Background: This report aims to supplement the existing knowledge on the inferior oblique muscle. In particular, this study presents detailed anatomical and histological data concerning the muscle's entry point (or entry zone) of the nerve to the inferior oblique muscle. Particular attention was paid to the topographical relationships of the nerve to the inferior oblique muscle (NTIO), including the location of its entry point to the muscle's belly and its anatomical variations. Methods: Sixty orbits from cadaveric hemi-heads fixed in 10% formalin were studied. The course of the NTIO was traced along the lateral border of the inferior rectus muscle as far as its entry point to the inferior oblique muscle. Particular attention was paid to the various ways in which the NTIO's muscular sub-branches penetrated between the fibers of the inferior oblique muscle. Results: Three types of NTIO entries to the inferior oblique muscle's belly were distinguished. In the most common type (48.3%), the nerve entered the muscle's inferior (orbital) surface. In the next most common type (36.7%), terminal muscular sub-branches of the NTIO joined the superior (also referred to as ocular or global) surface of the inferior oblique muscle. In the remaining four cases (15%), the terminal sub-branches of the NTIO were divided into two main groups (superior and inferior) that joined both the superior and inferior surfaces of the muscle. Histological examination confirmed that the distal part of the NTIO shows a characteristic arcuate course (angulation) just before reaching the muscle's belly. The process for splitting and forming separate muscular sub-branches of the NTIO was observed for all the examined histological specimens at the level of the nerve's angulation. Conclusions: The presented findings enhance the understanding of the anatomical variations and precise distribution of motor sub-branches reaching the inferior oblique muscle, which may deepen anatomical knowledge and potentially enhance the management of ocular motor disorders. [ABSTRACT FROM AUTHOR]

The goal of this study was to evaluate sensitivity of intraoperative Computed Tomography (iCT) imaging for the detection of orbital foreign bodies (OFBs) in an in vitro model and evaluate iCT efficacy for surgical planning of OFB detection and removal in veterinary patients. Three canine patients were presented to our hospital for potential orbital foreign body removal. In vitro studies were conducted using a canine skull model with placement of various OFBs. Four different examiners utilized CT imaging to evaluate the detection of OFBs. A surgical navigation system was employed to assess the feasibility of stereotactic orbital foreign body retrieval in vitro. iCT imaging was applied for surgical planning and guidance of orbital surgery for the removal of OFBs in three clinical patients. In vitro experiments revealed a high detection rate for objects with high radiopacity such as metal and glass. The detection rate for organic foreign bodies such as wood was moderate, while for plastic foreign bodies ranged from moderate to low. Navigation was successfully used for OFB retrieval. iCT was effectively employed for detecting OFBs in clinical patients. However, porcupine quills were better detected using standard ultrasound imaging. The use of iCT potentially represents an evolving technological practice that enables real-time imaging to improve the precision of surgical procedures. [ABSTRACT FROM AUTHOR]

Background: Teprotumumab, a novel IGF-1R antibody, has been shown to significantly reduce the signs of acute and chronic Thyroid Eye Disease (TED). Light sensitivity is a reported symptom in patients with TED. There is a lack of a prospective study that has explored the effects on light sensitivity in a large cohort of patients with acute and chronic TED following treatment with teprotumumab. Methods: Consecutive patients who were diagnosed with TED and reported light sensitivity at baseline were considered for study eligibility. All patients had measurements of Visual Light Sensitivity Questionnaire-8 (VLSQ-8), proptosis, clinical activity score (CAS), and MRD1 (distance between the upper eyelid margin and corneal reflex, mm) and MRD2 (distance between the lower eyelid margin and corneal reflex, mm) before and after treatment. Results: Ninety patients (41 acute, 49 chronic) met the inclusion criteria. The mean (SD) age was 47.3 (14.3). Eighty-six (95.6%) patients completed all 8 infusions. There was a significant reduction in the total score and across all categories of the VLSQ-8 (p < 0.01 for all). Seventy-two (80%) patients had a clinically significant improvement (≥2 reduction) in at least one category. There was no significant difference in the total VLSQ-8 score between the acute and chronic group (p = 0.8). Conclusion: Teprotumumab improves light sensitivity in patients with acute and chronic TED. The results of this study highlight that the improvements in light sensitivity following treatment are not directly related to the mechanical changes in TED, suggesting another underlying mechanism is potentially involved. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate axial length (AL), orbital width (OW) and height (OH) development in congenital microphthalmia and anophthalmia (MICA) using serial ultrasonography measurements. Methods: A longitudinal prospective cohort (n = 74) of unilaterally and bilaterally affected MICA patients was followed from 2013 to 2022 at the university hospital in Amsterdam, the Netherlands. Clinical entity, age, severity category based on axial length, conformer treatment and intra‐orbital cysts were registered. The main outcome measures were the absolute and relative growth of AL, OW and OH. Surgical and intra‐orbital cyst cases were described separately. Results: Absolute microphthalmic eye size increased in 27/49 (55%) unilateral MICA eyes, but growth arrest/decrease in the remaining could shift the case to a more severe category over time. A final affected/unaffected orbital symmetry ≥80% was seen in the large majority of unilateral cases (45/46 for OW, 43/46 for OH). Cases with AL < 10.5 mm had orbital symmetry <80% more often. Most orbital symmetry changes were seen in moderate and severe unilateral cases treated with 3D‐printed conformer therapy starting at age <1 year, with 6/10 (60%) symmetry increase, 30% unchanged symmetry and 10% symmetry decrease. All cases older than 6.5 years (n = 6) did not show any change anymore, regardless of treatment. For bilateral and unilateral mild cases, orbital dimensions kept the same proportions during follow‐up, with or without conformer treatment. Conclusions: Using severity categories in MICA based on relative AL may aid the decision to start conformer treatment, as most orbital symmetry changes were seen in moderate and severe unilateral cases receiving 3D‐printed conformer therapy that started under age 1. [ABSTRACT FROM AUTHOR]

Background: Orbital involvement of invasive fungal sinusitis (IFS) is an ominous prognostic marker that should prompt rapid intervention. Transcutaneous retrobulbar administration of amphotericin B (TRAMB) is an off-label adjunctive treatment that can increase drug penetrance into diseased orbital tissue. To date, there is a lack of consensus regarding the use of TRAMB for treatment of IFS with orbital involvement. Objective: This systematic review aims to synthesize the indications, efficacy, and potential complications of TRAMB. Methods: PubMed, EMBASE, and Web of Science databases were probed for systematic review. Article search was conducted through June 2023 using the keywords "invasive fungal sinusitis," "invasive fungal rhinosinusitis," "rhino-orbital mucormycosis," "rhinosinusitis," "orbital," "retrobulbar," and "amphotericin." Results: In suitable cases as determined by radiologic and clinical evaluation, TRAMB administration has the potential to improve orbital salvage rates and improve versus stabilize visual acuity. Treatment complications are more likely with deoxycholate than with liposomal amphotericin formulations. The existing literature describing use of TRAMB is limited due to its retrospective nature, but the increase in IFS cases since 2020 due to the COVID pandemic has broadened the literature. Conclusions: TRAMB is an effective adjunctive treatment in IFS with mild-to-moderate orbital involvement when used in combination with standard of care debridement, systemic antifungal therapy, and immunosuppression reversal. Prospective longitudinal studies and multi-institutional randomized trials are necessary to determine the definitive utility of TRAMB. [ABSTRACT FROM AUTHOR]

This article discusses the history and significance of comets in our solar system. Comets have been observed and recorded throughout history, often being viewed as signs of good or bad times depending on the culture. The article also mentions notable comets that have gained public interest in recent years, such as Comet NEOWISE and Comet C/2022 E3 (ZTF). It introduces Comet C/2023 A3 Tsuchinshan-ATLAS, which was discovered in early 2023 and is expected to reach perihelion on September 27, 2024. The article provides tips for viewing comets and highlights the educational value of studying them. [Extracted from the article]

Background: There are no large studies reporting oncological or survival outcomes for patients diagnosed with perineural spread (PNS) of cutaneous squamous cell carcinoma (cSCC) via the ophthalmic nerve (V1). Where orbital exenteration may be necessary for curative treatment, it is critical to have survival data with which the morbidity associated with surgical treatment can be justified. Furthermore, with the emerging treatment option of immunotherapy, current standard of care outcomes are needed to help guide future trial design and eventually changed management guidelines. Objective: To determine the oncological and survival outcomes observed in patients with PNS of cSCC via V1. Materials and methods: Retrospective analysis of prospectively maintained cohort of patients with PNS of cSCC via V1 treated in a tertiary Australian head and neck oncology/skull base referral center. Consecutive sample of 53 patients managed between March 1, 1999 and April 30, 2020. Follow‐up closure date was September 1, 2021. Curative‐intent surgery, curative‐intent radiotherapy, or palliative care was undertaken. Endpoints included five‐year overall, disease‐specific, and disease‐free survival from the date of treatment. Results: Five‐year Kaplan–Meier overall survival was 61.9% (95% CI 46.2%–74.3%), with disease‐specific survival of 74.6% (95% CI 58.8%–85.3%), and disease‐free survival 62.1% (95% CI 46.5%–74.3%). Survival was superior in patients treated via surgery and adjuvant radiotherapy than in those receiving surgery alone or definitive radiotherapy. Survival was superior among patients with less advanced disease as assessed by the Williams zonal staging system; patients with Zone 1 disease had disease‐specific survival of 94.1% at 5 years with 82.5% disease‐free survival. Discussion: Five‐year oncological and survival outcomes in this cohort were favorable. Superior survival was observed in patients treated with curative‐intent surgery and adjuvant radiotherapy. Less extensive disease as delineated by the Williams zonal staging system was associated with improved survival. Conclusion: Surgical resection with adjuvant radiotherapy confers favourable oncological and survival outcome in patients with V1 PNS, particularly with early disease limited to Zone 1. [ABSTRACT FROM AUTHOR]

Background and Aim: The annual risk of major bleeding due to anticoagulant use ranges from 2% to 5%, with 0.5% to 1% of these bleedings being fatal. The global usage of oral anticoagulants is 0.65%, with warfarin being the most commonly used oral anticoagulant agent. In our study, we aimed to determine the long-term bleeding risks of patients using warfarin in our clinic and to make treatment and risk factor adjustments according to this risk situation. We investigated the effectiveness of the most commonly used bleeding risk scores and their superiority over one another in this study. Materials and Methods: This study included patients taking warfarin from January 2010 to January 1, 2022. Demographic data, laboratory parameters, known, and potential bleeding risk factors were recorded for all patients. Pre-treatment CHA2DS2-VASc, ATRIA, HAS-BLED, and ORBIT scores were calculated for all patients included in the study, along with their time in therapeutic range (TTR) values during follow-up. Patients were retrospectively monitored for bleeding events. Results: In our study, we observed that anemia, chronic kidney failure, cancer, and mechanical valves were associated with an increased risk of bleeding compared with other risk factors. We found that among the risk scores assessed in patients, the HAS-BLED risk score more strongly predicted the risk of bleeding than the other risk scores. Additionally, we found that low TTR values were directly associated with bleeding. Conclusion: Modifying identified risk factors in patients during the warfarin treatment process (such as anemia, chronic kidney failure, etc.) may reduce the risk of bleeding. Similarly, close monitoring of TTR, particularly in patients with high HAS-BLED and ORBIT risk scores assessed before treatment initiation, is considered a safe treatment approach to reduce the risk of bleeding. [ABSTRACT FROM AUTHOR]

Optic nerve coloboma is a congenital defect caused by the incomplete closure of the embryonic fissure. This closure begins around the fifth week of gestation, when the embryo measures approximately 7 to 14 mm. Colobomas may appear as isolated defects or alongside other ocular and systemic abnormalities. They typically occur in the inferonasal quadrant, where the optic vesicle undergoes closure. This closure process starts centrally within the eye and progresses both anteriorly and posteriorly. The distinct nature of these closures can result in an optic nerve coloboma without an associated iris coloboma.The formation of a coloboma can be attributed to external factors affecting the fetus during pregnancy or to a genetic mutation, such as an autosomal dominant mutation in the Pax gene, which is linked to bilateral colobomas. Small colobomas generally require only clinical and radiological observation, whereas larger colobomas may need surgical intervention to remove the cyst and prevent complications related to orbital content development, thereby improving cosmetic outcomes

Purpose: to assess the clinical course of metastatic orbital tumors (MOT) and the results of instrumental examination of patients. Material and methods. 50 MOT patients aged 5–84 years (ave. 56.9 ± 14.3), including 41 women (82 %) and 9 men (18 %), were examined for the clinical signs, the laterality of the lesion, the size and shape of the tumor, the presence of oncology in the clinical history and its duration. All patients underwent ultrasound examination with color Doppler imaging (CDI), plus computer tomography (CT) or magnetic resonance imaging (MRI) of the orbits. In all cases, the diagnosis of MOT was confirmed morphologically. Results. 32 (64 %) patients had an oncology history, which lasted from 9 months to 23 years (median 5 years). The most frequently observed metastases were those of breast cancer (27 cases, 54 %), while other types occurred much less frequently: metastases of kidney cancer (4 cases) and stomach (3 cases), cancers of the reproductive systems (2 cases), melanoma (3 cases), thyroid cancer (1 case), and sarcomas (4 cases). The primary focus could not be detected in 3 patients (6 %). OD/OS orbit damages were observed in 23 patients (46 %)/ 21 patients (42 %), while 6 patients (12 %) had bilateral damages. Clinical symptoms included exophthalmos (35 cases, 70 %), enophthalmos (6 cases, 12 %), eye movement impairment (35 cases, 70 %), ptosis (35 cases, 70 %), eyelid edema (24 cases, 68 %), pain in the orbit (7 cases, 14 %), chemosis (12 cases, 24 %), difficulty in eye repositioning (32 cases, 64 %). Decreased visual acuity was noted in 13 cases (26 %). CT symptoms included infiltrative nature of the lesion (43 patients, 86 %), and solid tumors with clear and even contours (7 patients, 14 %). Bone wall changes were detected in 7 patients (14 %). Ultrasound data revealed a heterogeneous structure and an increased acoustic density of MOT. CDI detected own vessels in the projection of the tumor (15 patients). Conclusion. Orbital metastases present a multidisciplinary problem, which requires mandatory monitoring by physicians of various specialties, as only 36% of patients have no oncology in their clinical histories. Specific history features, the patient’s complaints, typical clinical symptoms, CT (MRI) and ultrasound data should alert the ophthalmologist about a possible MOT. A mandatory examination of patients with malignant neoplasms by an ophthalmologist is necessary to exclude ocular metastases.

Abstract In this study, we aimed to follow up on the surprising increase in the incidence of orbital subperiosteal abscesses (SPA) reported in the Iranian pediatric population in the post-COVID era. Pediatric patients (≤ 18 years old) diagnosed with orbital SPA following acute sinusitis who were hospitalized between October 1st, 2023, and March 31st, 2024 in Farabi Eye Hospital, Tehran, Iran, were included. Demographic, clinical, microbiologic, and radiological characteristics of patients were reviewed. During the 6-month study period, 39 patients were admitted to our tertiary referral hospital. The average age of patients was 7.29 ± 4.13 years and 30 patients (76.92%) were male. The ethmoid sinus was involved in 100% of patients, and SPA involvement was in the medial wall in 27 patients (69.23%). The mean volume of SPA was 1.45 ± 1.77 cm3. Nineteen patients (48.72%) underwent surgical interventions, however, 20 patients (51.28%) received only medical treatment. The best corrected visual acuity of patients increased from 0.63 (0.20 LogMAR) on the first day of admission to 0.84 (0.07 LogMAR) according to the Snellen chart in the first month after treatment. It seems that the outbreak of orbital SPA in the Iranian children population in the post-COVID era is an increasing trend.

AIM: To compare the exposure rate, infection rate, percentage of enhancement, and success rate between Medpor and the three-dimensional printed polyethylene (3DP-PE) orbital implant in a preliminary report. METHODS: This prospective, randomized, equivalence, controlled trial was conducted at two institutes. The equivalent margin was ±10%. The sample size for the equivalence trial was 174 participants per group. Patients who were eligible for enucleations received either Medpor or 3DP-PE implants based on a randomized block of six. The surgeries were performed by five oculoplastic surgeons. The assessor and patients were masked. The magnetic resonance imaging (MRI) of the orbit was performed at least 6mo after operation and the fibrovascular ingrowth was analyzed using the Image J software. Follow-up continued at least 1y after surgery. The intention to treat and per protocol approaches were used. RESULTS: Totally 128 patients met the criteria in the report. Fifty Medpor and 55 3DP-PE cases completed the trial. The most common cause of blindness was trauma. The mean follow-up times of Medpor and 3DP-PE were 33 and 40mo respectively. The exposure rate was not statistically significant between two groups (6.0% and 7.3%), P

Background and Aim: The annual risk of major bleeding due to anticoagulant use ranges from 2% to 5%, with 0.5% to 1% of these bleedings being fatal. The global usage of oral anticoagulants is 0.65%, with warfarin being the most commonly used oral anticoagulant agent. In our study, we aimed to determine the long-term bleeding risks of patients using warfarin in our clinic and to make treatment and risk factor adjustments according to this risk situation. We investigated the effectiveness of the most commonly used bleeding risk scores and their superiority over one another in this study. Materials and Methods: This study included patients taking warfarin from January 2010 to January 1, 2022. Demographic data, laboratory parameters, known, and potential bleeding risk factors were recorded for all patients. Pre-treatment CHA2DS2-VASc, ATRIA, HAS-BLED, and ORBIT scores were calculated for all patients included in the study, along with their time in therapeutic range (TTR) values during follow-up. Patients were retrospectively monitored for bleeding events. Results: In our study, we observed that anemia, chronic kidney failure, cancer, and mechanical valves were associated with an increased risk of bleeding compared with other risk factors. We found that among the risk scores assessed in patients, the HAS-BLED risk score more strongly predicted the risk of bleeding than the other risk scores. Additionally, we found that low TTR values were directly associated with bleeding. Conclusion: Modifying identified risk factors in patients during the warfarin treatment process (such as anemia, chronic kidney failure, etc.) may reduce the risk of bleeding. Similarly, close monitoring of TTR, particularly in patients with high HAS-BLED and ORBIT risk scores assessed before treatment initiation, is considered a safe treatment approach to reduce the risk of bleeding.

PURPOSE: The purpose of this study was to compare the histopathologic inflammation and fibrosis of orbital adipose tissue in orbital inflammatory disease (OID) specimens. METHODS: In this retrospective cohort study, inflammation, and fibrosis in orbital adipose tissue from patients with thyroid-associated orbitopathy (TAO), granulomatosis with polyangiitis (GPA), sarcoidosis, nonspecific orbital inflammation (NSOI), and healthy controls were scored by 2 masked ocular pathologists. Both categories were scored on a scale of 0 to 3 with scoring criteria based on the percentage of specimens containing inflammation or fibrosis, respectively. Tissue specimens were collected from oculoplastic surgeons at 8 international centers representing 4 countries. Seventy-four specimens were included: 25 with TAO, 6 with orbital GPA, 7 with orbital sarcoidosis, 24 with NSOI, and 12 healthy controls. RESULTS: The mean inflammation and fibrosis scores for healthy controls were 0.0 and 1.1, respectively. Orbital inflammatory disease groups inflammation (I) and fibrosis (F) scores, formatted [I, F] with respective p -values when compared to controls, were: TAO [0.2, 1.4] ( p = 1, 1), GPA [1.9, 2.6] ( p = 0.003, 0.009), sarcoidosis [2.4, 1.9] ( p = 0.001, 0.023), and NSOI [1.3, 1.8] ( p ≤ 0.001, 0.018). Sarcoidosis had the highest mean inflammation score. The pairwise analysis demonstrated that sarcoidosis had a significantly higher mean inflammation score than NSOI ( p = 0.036) and TAO ( p < 0.0001), but no difference when compared to GPA. GPA had the highest mean fibrosis score, with pairwise analysis demonstrating a significantly higher mean fibrosis score than TAO ( p = 0.048). CONCLUSIONS: Mean inflammation and fibrosis scores in TAO orbital adipose tissue samples did not differ from healthy controls. In contrast, the more intense inflammatory diseases such as GPA, sarcoidosis, and NSOI did demonstrate higher histopathologic inflammation and fibrosis. This has implications in prognosis, therapeutic selection, and response monitoring in orbital inflammatory disease.

BackgroundAcute invasive fungal sinusitis (AIFS) is an aggressive disease that requires prompt diagnosis and multidisciplinary treatment given its rapid progression. However, there is currently no consensus on diagnosis, prognosis, and management strategies for AIFS, with multiple modalities routinely employed. The purpose of this multi-institutional and multidisciplinary evidence-based review with recommendations (EBRR) is to thoroughly review the literature on AIFS, summarize the existing evidence, and provide recommendations on the management of AIFS.MethodsThe PubMed, EMBASE, and Cochrane databases were systematically reviewed from inception through January 2022. Studies evaluating management for orbital, non-sinonasal head and neck, and intracranial manifestations of AIFS were included. An iterative review process was utilized in accordance with EBRR guidelines. Levels of evidence and recommendations on management principles for AIFS were generated.ResultsA review and evaluation of published literature was performed on 12 topics surrounding AIFS (signs and symptoms, laboratory and microbiology diagnostics, endoscopy, imaging, pathology, surgery, medical therapy, management of extrasinus extension, reversing immunosuppression, and outcomes and survival). The aggregate quality of evidence was varied across reviewed domains.ConclusionBased on the currently available evidence, judicious utilization of a combination of history and physical examination, laboratory and histopathologic techniques, and endoscopy provide the cornerstone for accurate diagnosis of AIFS. In addition, AIFS is optimally managed by a multidisciplinary team via a combination of surgery (including resection whenever possible), antifungal therapy, and correcting sources of immunosuppression. Higher quality (i.e., prospective) studies are needed to better define the roles of each modality and determine diagnosis and treatment algorithms.

In this paper, we delve into the investigation of real fixed points of a two-parameter family of functions defined as [Formula: see text] where [Formula: see text] and m is a natural number. Our focus is to study the real fixed points of [Formula: see text] and understand their nature. Throughout our analysis, we discover that the number of fixed points depends on the values of α and the parity of m. Furthermore, we find that the number of fixed points of [Formula: see text] does not change for any odd or even value of m, provided [Formula: see text] In each case of m and [Formula: see text] we conclude that the family of functions [Formula: see text] has exactly one attracting fixed point, two indifferent fixed points, and more than two repelling fixed points.

Fermat’s two squares theorem asserts that a prime one more than a multiple of 4 is a sum of two squares. There are many proofs of this gem in number theory, including a remarkable one-sentence proof by Don Zagier based on two involutions on a finite set built from such a prime. Applying the two involutions alternatively leads to an iterative algorithm to find the two squares for the prime. Moreover, a detailed analysis of the computation reveals that it is possible to jump through the iteration nodes, leading to a better hopping algorithm. Here is a formalisation of Zagier’s proof, deriving the involutions using windmill patterns. Theories developed for the formal proof are used to establish the correctness of both algorithms. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the clinical features, radiographic features, treatment strategies, pathological features, and prognosis of orbital cholesterol granuloma (CG). Methods: Twelve patients with orbital CG who were referred to Tianjin Eye Hospital between January 2002 and December 2020 were included in this retrospective case series study. Data collected including patient ophthalmic manifestations, imaging findings, treatment strategies, pathological features, and prognosis were retrospectively reviewed. Results: The patients comprised 10 males and 2 females. The mean age was 34.5 years (standard deviation [SD] = 8.9, median: 36 and range: 16–45 years). Four patients had a history of orbital trauma. The clinical manifestations at the first visit were proptosis (7/12, 58.3%), periorbital or eyelid swelling (6/12, 50%), limitation of eye movement (4/12, 33.3%), ptosis (2/12, 16.7%), and decreased visual acuity (1/12, 8.3%). Computed tomography (CT) showed a nonenhancing, well-circumscribed lesion in the orbit with extensive erosion of the adjacent frontal bone and temporal bone. Magnetic resonance imaging (MRI) showed a nonenhancing mass with intermediate-to-high signal intensity on T1- and T2-weighted images. Ten patients underwent lateral orbitotomy, and two patients underwent supraorbital orbitotomy. All patients had aggressive bone erosion. Histopathologic evaluation of the cyst contents and wall revealed cholesterol clefts, multinucleated giant cells, histiocytes, foamy macrophages, and altered blood pigments. The mean follow-up time of 79.6 months (SD = 49.8, range: 19–193 months). Three patients were lost to follow-up. No postoperative diminution of vision was noted, and no recurrence was observed. Conclusions: CGs can present as superotemporal or temporal orbital lesions. The diagnosis can be established based on CT and MRI. Most of the patients can have no history of orbital trauma.

In the quaternion formulation, the problem of mathematical modeling of the spacecraft motion in an elliptical orbit is considered. The control is a modulo-limited acceleration vector from the jet thrust, directed orthogonally to the plane of the spacecraft orbit. The motion of the spacecraft center of mass is described using the quaternion differential equation of the orientation of the orbital coordinate system. An approximate analytical solution of the quaternion differential equation of the orientation of the orbital coordinate system is constructed in the form of a uniformly suitable asymptotic expansion by degrees of eccentricity of the spacecraft orbit (small parameter). To eliminate the secular terms in this expansion, the renormalization method was applied. Taking into account the known solution of the equation of orientation of the orbital coordinate system for the case when the spacecraft orbit is circular, allowed to simplify the form of the above expansion. The nonlinear oscillation frequencies of each component of the desired quaternion were found. Analytical transformations were performed using the SymPy symbolic algebra package. To carry out numerical simulation of the spacecraft motion, a program was written in Python. Calculations based on analytical formulas obtained in the paper (in the absence of secular terms) and previously obtained results in the presence of secular terms are compared. An example of modeling the controlled motion of a spacecraft is given for the case when the initial orientation of the orbital coordinate system corresponds to the orientation of the orbit of one of the satellites of the GLONASS orbital grouping. Graphs were built to show error in the module (and components) of the quaternion describing the orientation of the orbital coordinate system. It is shown that the elimination of secular terms using the renormalization method made it possible to reduce the error in determining this module with an increase in the number of spacecraft revolutions around the Earth. The analysis of the obtained approximate analytical solution is carried out. The features and regularities of the spacecraft motion in an elliptical orbit are established.

Background: Given a rising tendency in the rate of ocular trauma, there is an increasing need in surgeries for orbital, ocular adnexal and periorbital reconstruction. The susceptibility to resorption is a common drawback of the biological tissues used as a plastic material in contemporary orbital surgery. Non-biological hollow porous polyvinyl formal (PVF) hydrogel implants capable of integration with adjacent biological tissues offer a new opportunity for reconstructive surgery. Purpose: To examine the in vivo and in vitro biocompatibility of a synthetic PVF-based hydrogel implant material. Material and Methods: Scanning electron microscopy (SEM) analysis; in vitro evaluation of the biocompatibility of the PVF hydrogel implant material in terms of its cytotoxicity, genotoxicity and effects on marker enzymatic activities of L929 fibroblasts; and in vitro study on implant incorporation. Results: A cross-linked polyvinyl formal hydrogel for orbital endoprosthesis surgery was synthesized. Our in vitro cytotoxicity and genotoxicity tests of the hydrogel and tests of its effects on marker enzymatic activities of L929 fibroblasts demonstrated safety. All hydrogel implant samples, after being sealed into polypropylene bags and autoclaved for 15 min at 121 °C and 1.04 atm steam pressure, were found to be sterile. In all rats in which the hybrid hydrogel implant was placed subcutaneously in the back, there was prompt relief of edema at the site of postoperative suture. The inflammatory reactions seen in the tissues adjacent to the implant included mostly mild diffuse lymphocytic infiltration close to the implant surface, with no inflammatory reactions seen at the sites more remote from the implant. Conclusion: Our in vivo and in vitro study of the PVF hydrogel demonstrated its high biocompatibility in terms of its cytotoxicity, genotoxicity and effects on marker enzymatic activities of fibroblast cells, with no post-implantation complications, but a step-by-step improvement in the relationship between the implant and adjacent tissues. The findings of this study allow us to recommend the developed PVF hydrogel for further research on the potential for using it as an implant for filling postoperative cavities and endoprosthesis in orbital and periorbital reconstruction.

Short arc orbit determination for GEO satellites is useful when there are gaps or incomplete data due to limited time or other factors. Full cycle orbit determination requires continuous data over the entire orbit cycle, which may not always be available. This research assesses the accuracy of short arc orbit determination for GEO satellites for various time intervals ranging from 6-hour- to 42-hour intervals using two data collecting techniques: azimuth elevation range (AER) and range-to-range (RNG). Iterative Least-Squares Estimation, a numerically integrated method, is then used to determine the orbit, by either calculating new bias values or preexisting bias values. The results show that average root mean square error (RMSE) values are 0.792 km and 0.160 km for AER and RNG type observation data, respectively, using pre-existing bias values. On the other hand, using new bias calculation, the average RMSE values are 36.480 km and 6.254 km for AER and RNG. The findings indicate that the RNG method provides superior accuracy in determining the orbit for both satellites. The study recommends the use of pre-existing bias values over calculating new ones. Short arc orbit determination can provide a reasonable estimate of the satellite's orbit when a limited amount of data is available due to various reasons and can also be used to quickly assess and correct any deviations or errors in the satellite's orbit, improving overall accuracy and reliability.

Deep learning has been extensively applied to medical image segmentation, resulting in significant advancements in the field of deep neural networks for medical image segmentation since the notable success of U-Net in 2015. However, the application of deep learning models to ocular medical image segmentation poses unique challenges, especially compared to other body parts, due to the complexity, small size, and blurriness of such images, coupled with the scarcity of data. This article aims to provide a comprehensive review of medical image segmentation from two perspectives: the development of deep network structures and the application of segmentation in ocular imaging. Initially, the article introduces an overview of medical imaging, data processing, and performance evaluation metrics. Subsequently, it analyzes recent developments in U-Net-based network structures. Finally, for the segmentation of ocular medical images, the application of deep learning is reviewed and categorized by the type of ocular tissue.

Abstract Background Echinococcosis, commonly known as hydatid disease, is a zoonotic infection resulting from the tapeworm Echinococcus granulosus. The occurrence of hydatid cysts in the orbital region is uncommon, representing less than 1% of all reported hydatid cases. This report details a unique case of an intramuscular hydatid cyst in the orbital region that led to compressive optic neuropathy. Case Presentation A 22-year-old male from Kabul, Afghanistan presented with a five-month history of progressive proptosis in his left eye, associated with a gradual decrease in vision over the past three weeks. The left eye exhibited upward globe dystopia, ocular motility limitation, mild conjunctival injection, and chemosis. Diagnosis was achieved through imaging and histopathological examination. Treatment involves surgical removal of the cyst and prolonged albendazole therapy. The postoperative course showed significant improvement in the patient’s condition and restoration of his vision. Conclusions Despite its rarity, this case underscores the importance of awareness and knowledge of hydatid disease among physicians, especially those working in endemic areas. It emphasizes the importance of including hydatid disease in the differential diagnosis of orbital masses, particularly in endemic regions.

AbstractIntroduction: Pediatric orbital tumors encompass a wide spectrum of neoplasms, many of which are malignant small round cell tumors with overlapping histology. Sarcomas with BCOR genetic alterations are undifferentiated round cell sarcomas (URCS) characterized by BCOR rearrangements or internal tandem duplications, having distinct clinical features. Being previously unrecognized in the orbit, they have potential for misdiagnosis. Patients: We describe two cases of orbital sarcomas with BCOR genetic alterations. Results: Both girls, 8 and 16 months of age, respectively, presented with progressive proptosis. Both tumors showed sheets of round to ovoid cells with monomorphic nuclei and frequent mitoses. Delicate branching capillaries and myxoid stroma were absent. Diffuse BCOR, cyclin D1, and SATB2 immunopositivity was present. Conclusion: Orbital sarcomas with BCOR genetic alterations are extremely rare. Pathologists should have high index of suspicion for novel genetically defined entities in the differential diagnosis of pediatric orbital URCS and perform appropriate ancillary tests for accurate diagnosis. [ABSTRACT FROM AUTHOR]

Tessier number 10 cleft is one of the rarest facial clefts. Surgical treatment of this type of cleft is challenging due to the complexity of periorbital and temporal soft tissue deformities. A 23-year-old male patient presented with typical facial deformities of Tessier number 10 cleft. The surgical procedure involved using a free anterolateral thigh flap to reconstruct the eye socket, while the superficial temporal artery pedicle scalp flap was used to reconstruct the eyebrow deformity. The patient had no complications and 16 months after surgery, the patient had good aesthetic results. A hair-bearing scalp flap with a pedicle of the frontal branch of the superficial temporal artery combined with an anterolateral thigh-free flap can effectively resolve most soft tissue deformities of Tessier number 10 cleft and reconstruct the orbital socket in a single surgery. At the same time, it augments the soft tissue of the frontotemporal area and provides good aesthetic results. [ABSTRACT FROM AUTHOR]

MALT lymphoma is a commonly encountered orbital tumor, and primary amyloidosis is frequently found to be an independent orbital lesion. Orbital MALT lymphoma with associated amyloid deposition is considered rare, with only 12 cases previously published. We describe a 33-year-old man, the youngest patient reported to-date, with a mass in the superonasal quadrant of the right anterior orbit. Pathology demonstrated extranodal marginal zone lymphoma in mucosa-associated lymphoid tissue with associated amyloid deposition. Systemic work-up revealed no other site of either lymphoma or amyloidosis. The patient underwent local irradiation and subsequent surgical resection of the residual mass. Persistent lymphoma was found and treated with rituximab. [ABSTRACT FROM AUTHOR]

A 37-year-old, previously healthy woman presented during her first trimester of pregnancy with a two-week history of rapidly progressive proptosis in the left eye. Clinical examination revealed limited left supraduction and diplopia in upward gaze. Orbital magnetic resonance imaging showed a medial orbital mass adjacent to the globe with secondary proptosis. Pathologic examination of a biopsied specimen of the orbital mass and subsequent immunophenotyping by flow cytometry revealed an extranodal marginal zone B-cell lymphoma. Clinical and histological features as well as a review of the literature are described. [ABSTRACT FROM AUTHOR]

Rhabdomyoma of the orbit is a rare tumor with very few cases reported in the literature. We herein describe a 5-year-old boy who presented to us with a deviation of his left eye. Magnetic Resonance Imaging (MRI) showed a well-defined homogeneous intraconal mass in the superomedial aspect compressing the optic nerve. An excision biopsy was performed and the diagnosis of rhabdomyoma was confirmed on histopathology and immunohistochemistry with a coincidental finding of Trichinella spiralis larvae within the excised specimen. We report this phenomenon in two rare diseases with a predilection for striated muscle occurring simultaneously in a single patient. [ABSTRACT FROM AUTHOR]

Background: This report aims to present the case of a pediatric patient with a recurrent tumor in the superolateral orbit. Clinical Presentation: An 8-year-old patient was initially treated for a tumor in the superolateral orbit via a transconjunctival approach. The histopathological diagnosis was epidermoid cyst. Postoperatively, chronic inflammation and fistula developed in the lateral canthus area. Magnetic resonance imaging revealed a residual tumor posterior to the original tumor location. The patient was treated via a modified orbitozygomatic (mOZ) craniotomy approach that was originally applied in neurosurgery, and complete tumor removal was achieved. A temporary paralysis of the frontotemporal branch of the facial nerve was observed and fully resolved within one month following surgery. At the 18th month of follow-up, the visual, neurological, and cosmetic results were found to be satisfactory. Conclusions: mOZ craniotomy can be used to access and operate on recurrent orbital tumors in pediatric patients where other more aggressive surgical approaches should be avoided. [ABSTRACT FROM AUTHOR]

Primary apocrine adenocarcinoma (PAA) originating from the orbit is a rare malignant neoplasm. We present the case of a 61-year-old-male with PAA of the orbit. The patient underwent a right orbital exenteration, neck dissection, and adjuvant radiotherapy. Orbital exenteration is commonly performed as the primary intervention for PAA of the orbit. The role of adjuvant radiotherapy to prevent local recurrence is unclear and may be determined on a case-by-case basis. [ABSTRACT FROM AUTHOR]

Orbital inflammatory disease (OID) comprises approximately 6% of orbital conditions, affecting individuals across all ages. The range of the primary orbital inflammation's differential diagnosis is extensive, encompassing autoimmune disorders such as thyroid diseases, vasculitis, sarcoidosis, connective tissue diseases, immunoglobulin G4-related disease (IgG4-RD), and giant cell myositis, whereas secondary causes span from infections to drug-induced causes. Analyzing histopathological aspects and cell populations could enhance our comprehension of the etiology of orbital inflammatory involvement in systemic diseases such as IgG4-RD. We present a series of four patients from our Rheumatology clinic, each with distinct systemic diseases, illustrating diverse manifestations of OID. This series was conducted to facilitate discussions and diagnoses of challenging cases of OID in a rheumatologic setting. The difficulty in the differential diagnosis arises from the extensive range of structures involved, resulting in a significant variation of clinical manifestations. Furthermore, the lack of definitive diagnostic laboratory tests and, often, histological findings add to the complexity. OID poses diagnostic challenges with variable clinical manifestations and overlapping imaging findings. As a diagnosis of exclusion, a comprehensive evaluation is crucial, often necessitating an orbital biopsy for confirmation. Collaborative efforts among specialists are essential for managing these intricate cases. [ABSTRACT FROM AUTHOR]

This case report highlights a unique presentation of Erdheim-Chester Disease (ECD) with bilateral scleral lesions, choroidal infiltration, and extensive sinus involvement. It is the first case report where the diagnosis was confirmed through a scleral biopsy after an initial presentation of a unilateral nodular scleritis. There was a gradual disease progression and ocular examination later revealed bilateral subconjunctival hyperemic lesions and mild exophthalmos, ophthalmoplegia, and extensive choroidal infiltration. Infiltration of the frontal and maxillary sinus was present and extended into the nasal cavity and both orbits. The diagnostic work-up is described in detail. Current treatment options are analyzed. It is emphasized that the ophthalmologist can play a crucial role in the diagnosis of ECD, given the substantial prevalence of orbital and ocular symptoms. The overall prognosis for ECD remains unfavorable, particularly in cases with orbital involvement. This case underscores the complexity and importance of a multidisciplinary approach in managing ECD. [ABSTRACT FROM AUTHOR]