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SIGNIFICANCE: Spatial frequency domain imaging (SFDI) applies patterned near-infrared illumination to quantify the optical properties of subsurface tissue. The periocular region is unique due to its complex ocular adnexal anatomy. Although SFDI has been successfully applied to relatively flat in vivo tissues, regions that have significant height variations and curvature may result in optical property inaccuracies. AIM: We characterize the geometric impact of the periocular region on SFDI imaging reliability. APPROACH: SFDI was employed to measure the reduced scattering coefficient ( μ s ) and absorption coefficient ( μ a ) of the periocular region in a cast facial tissue-simulating phantom by capturing images along regions of interest (ROIs): inferior temporal quadrant (ITQ), inferior nasal quadrant (INQ), superior temporal quadrant (STQ), central eyelid margin (CEM), rostral lateral nasal bridge (RLNB), and forehead (FH). The phantom was placed on a chin rest and imaged nine times from an en face or side profile position, and the flat back of the phantom was measured 15 times. RESULTS: The measured μ a and μ s of a cast facial phantom are accurate when comparing the ITQ, INQ, STQ, and FH to its flat posterior surface. Paired t tests of ITQ, INQ, STQ, and FH μ a and μ s concluded that there is not enough evidence to suggest that imaging orientation impacted the measurement accuracy. Regions of extreme topographical variation, i.e., CEM and RLNB, did exhibit differences in measured optical properties. CONCLUSIONS: We are the first to evaluate the geometric implications of wide-field imaging along the periocular region using a solid tissue-simulating facial phantom. Results suggest that the ITQ, INQ, STQ, and FH of a generalized face have minimal impact on the SFDI measurement accuracy. Areas with heightened topographic variation exhibit measurement variability. Device and facial positioning do not appear to bias measurements. These findings confirm the need to carefully select ROIs when measuring optical properties along the periocular region.

Purpose:Methods:Results:Conclusion:To determine the incidence rates, risk factors, and economic burden of orbital and preseptal cellulitis in the United States (US).This retrospective longitudinal study was completed using data from the US Nationwide Emergency Department Sample dataset. An estimated 732,105 emergency department (ED) visits with a primary or secondary diagnosis of orbital and preseptal cellulitis from 2006 to 2018 were included. Incidence rates, descriptive statistics, and risk factors were calculated using linear and multivariate logistic regression models.The incidence rates of preseptal cellulitis increased from 6.2 in 2006 to 19.2 per 100,000 US population in 2018. In contrast, orbital cellulitis incidence rates have been decreasing from 6.1 to 2.8 per 100,000 US population from 2006 to 2018, respectively. Young adults (ages 21–44) comprise a majority of patients with either preseptal or orbital cellulitis (31.7%; 95% CI, 30.5–33.0%). Hypertension (11.8%, 12.9%), tobacco use (11.2%, 9.6%), and sinusitis (9.2%, 4.3%) were the most commonly associated diagnoses for orbital and preseptal cellulitis, respectively. Only 27.6% of patients with orbital cellulitis were admitted with 64.7% of patients routinely discharged. The inflation-adjusted ED charges for patients with orbital and preseptal cellulitis from 2006 to 2018 totalled over $997 million.Orbital and preseptal cellulitis are costly infections in the US with increasing incidence rates for preseptal cellulitis. High rates of routine discharge from the ED for orbital cellulitis may represent a knowledge gap amongst providers and an opportunity to improve care. Identifying individuals at risk for infection is key for diagnosis and appropriate triage of care. [ABSTRACT FROM AUTHOR]

Cation‐π interactions involve different metallic cations, where the bonding characteristics depend on the involved species. Here, we unravel the interaction nature features for Ga(I)‐π interactions, where different contributing terms ensure an efficient coordination of one and two Ga(I)‐atoms towards a common aromatic ring. Our results show a more balanced contribution of about ~70 % from electrostatic character and of ~30 % from orbital interaction for the prototypical GaCp, GaCp*, [Ga2Cp]+ and [Ga2Cp*]+ species. Such description strongly contrasts with the highly electrostatic character in alkali and alkaline‐earth metals counterparts. The variation from mono to inverted sandwich complexes leads to a decrease in the interaction energy from −180.9 to −148.1 kcal/mol for Cp based species, and from −184.4 to −155.5 kcal/mol in Cp* counterparts, owing to a decrease in both electrostatic and orbital stabilizing contributions. Thus, the aromatic rings exhibit coordination versatility towards one or two Ga(I) cations, retaining a sizable stabilization of the Ga(I)‐π interaction. Thus, cation‐π interactions are able to exhibit different types according to the involved metal cation, which relies on a more electrostatic/orbital balanced interaction, which serves to evaluate further mono and inverted sandwich complexes sharing a common aromatic ring. [ABSTRACT FROM AUTHOR]

Cation‐π interactions involve different metallic cations, where the bonding characteristics depend on the involved species. Here, we unravel the interaction nature features for Ga(I)‐π interactions, where different contributing terms ensure an efficient coordination of one and two Ga(I)‐atoms towards a common aromatic ring. Our results show a more balanced contribution of about ~70 % from electrostatic character and of ~30 % from orbital interaction for the prototypical GaCp, GaCp*, [Ga2Cp]+ and [Ga2Cp*]+ species. Such description strongly contrasts with the highly electrostatic character in alkali and alkaline‐earth metals counterparts. The variation from mono to inverted sandwich complexes leads to a decrease in the interaction energy from −180.9 to −148.1 kcal/mol for Cp based species, and from −184.4 to −155.5 kcal/mol in Cp* counterparts, owing to a decrease in both electrostatic and orbital stabilizing contributions. Thus, the aromatic rings exhibit coordination versatility towards one or two Ga(I) cations, retaining a sizable stabilization of the Ga(I)‐π interaction. Thus, cation‐π interactions are able to exhibit different types according to the involved metal cation, which relies on a more electrostatic/orbital balanced interaction, which serves to evaluate further mono and inverted sandwich complexes sharing a common aromatic ring. [ABSTRACT FROM AUTHOR]

Mucosa‐associated lymphoid tissue lymphoma or MALToma occurs in 8% of B‐cell non‐Hodgkin lymphoma according to the latest WHO classification. The most involved site of MALToma is stomach. We describe a rare case of concurrent gastric and orbital mucosa‐associated lymphoid tissue lymphoma (MALToma) of a female who presented with progressive proptosis and abdominal pain. We performed six courses of chemotherapy (Rituximab) and gastric and orbital radiation with a dose of 34 Gy/20 Fr and 30 Gy/20 Fr, respectively. This case underscores the efficacy of a multimodal treatment strategy in achieving successful outcomes. [ABSTRACT FROM AUTHOR]

Les fentes frontales orbitaires supérieures font partie des fentes rares craniofaciales décrites par Tessier en 1976, dont la survenue est le plus souvent sporadique. Elles sont numérotées 9, 10 et 11 dans cette classification et siègent respectivement latéralement, médianement et médialement vis-à-vis de la partie supérieure de l'orbite. Leurs expressions cliniques sont variables sur les tissus mous et osseux, avec une dissociation d'atteinte possible, et vont d'un simple défaut esthétique à la mise en jeu du pronostic fonctionnel oculaire. Le scanner est systématiquement justifié dans ce cadre. Leur prise en charge doit être adaptée au vu du polymorphisme des atteintes et repose sur une prise en charge multidisciplinaire, avec une reconstruction chirurgicale des parties molles urgente en cas de mise en jeu du pronostic oculaire. Dans les autres cas, la prise en charge est différée mais doit rester précoce afin de permettre un bon développement de l'enfant. Superior orbital frontal clefts are one of the rare craniofacial clefts described by Tessier in 1976, and occur most often sporadically. They are numbered 9, 10 and 11 in this classification, and are located respectively laterally, in the middle and medially to the upper part of the orbit. Their clinical expression is variable on soft tissue and bone, with possible dissociation of involvement. They range from a simple aesthetic defect to an eyes functional prognosis. CT scans are systematically required in this context. Their management must be adapted to the polymorphism of the damage, and is based on multidisciplinary approach. In case of ocular risk, the eyelid reconstruction is an emergency. In all other cases, treatment is deferred, but must be carried out at an early stage to ensure the child's healthy development. [ABSTRACT FROM AUTHOR]

Abstract The orbitofrontal cortex (OFC) is a large cortical structure, expansive across anterior-posterior axes. It is essential for flexibly updating learned behaviors, and paradoxically, also implicated in inflexible and compulsive-like behaviors. Here, we investigated mice bred to display inflexible reward-seeking behaviors that are insensitive to action consequences. We found that these mice also demonstrate insensitivity to Pavlovian-to-instrumental transfer, as well as compulsive-like grooming behavior that is ameliorated by fluoxetine and inhibitory, but not excitatory, chemogenetic modulation of excitatory OFC neurons. Thus, these mice offer the opportunity to identify neurobiological factors associated with inflexible and compulsive-like behavior. Experimentally bred mice suffer excitatory dendritic spine attrition, as well as changes in inhibitory synapse-associated proteins, GAD67/GAD1 and SLITRK3, largely in the anterior and not posterior OFC (or medial frontal cortex). They also display higher levels of the excitatory synaptic marker striatin in the nucleus accumbens and lower levels of the excitatory synaptic marker SAPAP3 in the dorsal striatum, striatal nuclei that receive input from the anterior OFC. Together, our findings point to the anterior OFC as a potential locus controlling action flexibility and compulsive-like behavior alike.

Dermoid cysts represent the most frequent type of orbital cystic lesions observed in children. While superficial orbital dermoid cysts manifest early in life as slowly growing masses, deep dermoid cysts typically remain clinically undetectable until adolescence or adulthood, at which point they enlarge and induce proptosis. Imaging studies play a pivotal role in precisely determining location and size, excluding intracranial and intraorbital extensions, and facilitating the planning of management strategies for complex cases.We present a case of a 5-year-old boy admitted for slowly developing of ocular motility limitation of the right eye, observed by the parents. The imaging revealed a well-circumscribed extraconal cystic mass, with radiological characteristics primarily suggesting a dermoid cyst. The cyst was surgically excised without complications, and the histopathological examination of the operative specimen confirmed our diagnosis.

Hydatid cyst, which is caused by the cestode echinococcus granulosus, is endemic in many countries around the world. Despite the frequency of this disease, no previous case of cerebral hydatid cyst with orbital extension has been reported, demonstrating the scarcity of this presentation. Cerebral hydatid cyst may be primary or secondary. Given to the nonspecifity of the clinical symptoms, cross sectional imaging, including CT and MRI, play an important role in the diagnosis by ruling out differential diagnoses, which are represented essentially by neoplastic and nonneoplastic intraparenchymal cysts as well as brain abscesses. Surgery remains the cornerstone treatment for cerebral and orbital hydatid cyst. In this article, we present the imaging findings of a patient with a primary cerebral hydatid cyst with orbital extension, and also the radiological features that could eliminate other differential diagnoses.

Abstract Background Enucleation and exenteration are widely utilized ophthalmic procedures in veterinary practice, involving the complete removal of the eye and comprehensive extraction of orbital contents, respectively. These procedures are indicated for pain relief, excision, and management of neoplasia metastases, and addressing severe medically untreatable conditions. Aim This study aimed to develop an orbital enucleation surgical approach. The study evaluated the applicability of the new approach and investigated the impact of the surgical procedure. Methods Anatomical dissection of three cadaveric heads and surgical orbital enucleation in four cadaveric heads were performed. Anatomical data was collected, and feasibility, safety and applicability of the procedure were assessed. Results Anatomical dissection showed a distinctive large orbital fossa, providing a suitable surgical window to access orbital structures. The procedure was found to be feasible, facilitating the complete removal of the orbital content. Notably, the preservation of intact eyelids was prioritized to enhance cosmetic appearance. Conclusion The presented orbital enucleation technique proved to be feasible, safe, reproducible, and required basic surgical skills to perform.

Solitary fibrous tumours (SFTs) are uncommon neoplasms originating primarily in the pleura but occasionally in the orbit. Despite their generally benign nature, they can exhibit aggressive behaviour. This study focuses on a rare case of a giant SFT located in the orbit, emphasizing diagnostic challenges and treatment considerations. A 69-year-old male with a history of progressive eyelid swelling, proptosis, and vision loss underwent a subconjunctival approach for the removal of an orbital SFT. Histopathological analysis, along with immunohistochemistry markers, confirmed the tumour’s identity. Successful tumour resection was achieved through the subconjunctival approach, highlighting the efficacy of this method for orbital SFTs. The histopathological examination revealed typical features of SFT, characterized by spindle cells and unique architectural patterns. Immunohistochemistry further supported the diagnosis. This case underscores the importance of considering orbital SFTs in the differential diagnosis of orbital tumours, particularly when confronted with proptosis and visual disturbances. Surgical excision, guided by radiological imaging and immunohistochemically analysis, remains the primary therapeutic approach. However, due to the potential for aggressive behaviour, further research is needed to optimize management strategies, especially in cases of incomplete resection or atypical behaviour.

Background: Enucleation and exenteration are widely utilized ophthalmic procedures in veterinary practice, involving the complete removal of the eye and comprehensive extraction of orbital contents, respectively. These procedures are indicated for pain relief, excision, and management of neoplasia metastases, and addressing severe medically untreatable conditions. Aim: This study aimed to develop an orbital enucleation surgical approach. The study evaluated the applicability of the new approach and investigated the impact of the surgical procedure. Methods: Anatomical dissection of three cadaveric heads and surgical orbital enucleation in four cadaveric heads were performed. Anatomical data was collected, and feasibility, safety and applicability of the procedure were assessed. Results: Anatomical dissection showed a distinctive large orbital fossa, providing a suitable surgical window to access orbital structures. The procedure was found to be feasible, facilitating the complete removal of the orbital content. Notably, the preservation of intact eyelids was prioritized to enhance cosmetic appearance. Conclusion: The presented orbital enucleation technique proved to be feasible, safe, reproducible, and required basic surgical skills to perform. [ABSTRACT FROM AUTHOR]

Mucormycosis is a serious fungal infection caused by fungi in the order of Mucorales. Orbital mucormycosis occurs more frequently in rhino-orbital, sino-orbital, and rhino-orbito-cerebral forms of the disease, while isolated orbital mucormycosis is much less common. Herein, we present four cases of immunocompetent children who developed primary cutaneous mucormycosis, which subsequently invaded and progressed to orbital mucormycosis following direct traumatic injury caused by pecking from Acridotheres tristis (Common Myna). Given the low prevalence of orbital mucormycosis in healthy children, an unknown source of infection and delayed diagnosis followed by late therapeutic interventions could result in life-threatening conditions and serious sequelae. [ABSTRACT FROM AUTHOR]

This case report explores a rare and aggressive Malignant Peripheral Nerve Sheath Tumor (MPNST) in a 7-year-old child affecting nasal sinuses, maxilla, and orbit, an exceptionally uncommon pediatric manifestation unrelated to Neurofibromatosis 1. The child presented with alarming symptoms—nasal obstruction, snoring, epistaxis, and difficulty swallowing—underscoring the case's urgency. Non-contrast computed tomography revealed an extensive mass infiltrating nasopharynx, nasal cavity, maxillary sinus, ethmoid sinuses, and orbit, causing destructive consequences. Histopathology confirmed a high-grade MPNST, marked by rapid growth and early metastasis, highlighting management challenges. The rarity of pediatric MPNST in the nasal cavity is discussed, emphasizing the need for a broad differential diagnosis. Treatment involves surgical resection and adjuvant chemoradiation with a grim prognosis due to diagnostic complexities and morphological mimicry in young patients. [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]

Objectives: To evaluate the combined performance of orbital MRI and intracranial visual pathway diffusion kurtosis imaging (DKI) in diagnosing dysthyroid optic neuropathy (DON). Methods: We retrospectively enrolled 61 thyroid-associated ophthalmopathy (TAO) patients, including 25 with DON (40 eyes) and 36 without DON (72 eyes). Orbital MRI–based apical muscle index (MI), diameter index (DI) of the optic nerve (ON), area index (AI) of the ON, apparent diffusion coefficient (ADC) and signal intensity ratio (SIR) of the ON, DKI-based kurtosis fractional anisotropy (KFA) and mean kurtosis (MK) of the optic tract (OT), optic radiation (OR), and Brodmann areas (BAs) 17, 18, and 19 were measured and compared between groups. The diagnostic performances of models were evaluated using receiver operating characteristic curve analyses and compared using the DeLong test. Results: TAO patients with DON had significantly higher apical MI, apical AI, and SIR of the ON, but significantly lower ADC of the ON than those without DON (p < 0.05). Meanwhile, the DON group exhibited significantly lower KFA across the OT, OR, BA17, BA18, and BA19 and lower MK at the OT and OR than the non-DON group (p < 0.05). The model integrating orbital MRI and intracranial visual pathway DKI parameters performed the best in diagnosing DON (AUC = 0.926), with optimal diagnostic sensitivity (80%) and specificity (94.4%), followed by orbital MRI combination (AUC = 0.890), and then intracranial visual pathway DKI combination (AUC = 0.832). Conclusion: Orbital MRI and intracranial visual pathway DKI can both assist in diagnosing DON. Combining orbital and intracranial imaging parameters could further optimize diagnostic efficiency. Clinical relevance statement: The novel finding could bring novel insights into the precise diagnosis and treatment of dysthyroid optic neuropathy, accordingly, contributing to the improvement of the patients' prognosis and quality of life in the future. Key Points: • Orbital MRI and intracranial visual pathway diffusion kurtosis imaging can both assist in diagnosing dysthyroid optic neuropathy. • Combining orbital MRI and intracranial visual pathway diffusion kurtosis imaging optimized the diagnostic efficiency of dysthyroid optic neuropathy. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to investigate the value of different iterative reconstruction algorithms for orbital computed tomography (CT). Methods: Orbital CT data from 31 patients were retrospectively collected from January to March 2024 at Beijing Tongren Hospital Capital Medical University. The images were reconstructed using both the Hybrid Iterative Reconstruction Algorithm (iDose4) and Iterative Model Reconstruction (IMR) techniques for the bone and standard algorithms. The average CT number, standard deviation (SD) of noise , signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and image quality scores of different reconstruction algorithms were compared. Randomized block variance analysis was used to compare differences in objective indicators, and the Wilcoxon signed-rank test for related samples was used to compare differences in subjective scores. Results: The differences in the CT number, noise, SNR, and CNR of images reconstructed using different standard algorithms were statistically significant. Compared with iDose4, the noise reduction of the IMR standard algorithm-reconstructed images ranged from 25% to 67%, with an SNR increase of 1.3~1.5 times, and a CNR increase of 2 to 3 times. Compared with iDose4, the noise reduction of the IMR bone algorithm-reconstructed images ranged from 70% to 96%, with an SNR increase of 5~15 times and a CNR increase of 4~31 times. The differences in the image quality scores of the images reconstructed using different bone and standard algorithms were statistically significant. The highest scores were 5 (5, 5) for the iDose4 Level 3 Y-Detail (YD) bone algorithm group and 5 (4, 5) for the IMR Level 1 Brain Routine standard algorithm group. The consistency of the scores evaluated by the two observers was strong, with weighted kappa coefficients ranging from 0.644 to 1. Conclusion: In orbital CT, we recommend using a hybrid iterative reconstruction technique (iDose4 Level 3) to reconstruct bone algorithm images and the iterative model reconstruction technique (IMR-Level 1) to reconstruct standard algorithm images.

For a safe sclerotherapy session to be completed in the orbital low-flow malformation (namely lymphovenous malformation or venolymphatic malformation), accurate identification of the target lesion for the drug injection is crucial. Regarding the dependability and viability of the injection approach, the authors have discussed their experiences with image-guided percutaneous sclerotherapy on a few patients.

The study investigates secondary students’ understanding of “orbital” and “electron cloud” concepts in different quantum contexts (for values of the ʽprincipal quantum number n = 1 and n = 2) on the basis of their verbal and pictorial representations, evaluating also their consistency. Participants, which were 192 12th-grade students from six urban secondary schools of Northern Greece, represented these two concepts through two corresponding tasks of a paper-and-pencil assessment tool, each of which comprised two parts for verbal and pictorial representations, respectively. Results provide evidence that although students struggle to express verbally the orbital and electron cloud concepts, their competences in the corresponding pictorial representations are relatively better, exhibiting inconsistencies between verbal and pictorial representations. Inconsistencies also exist between representations of the orbital and electron cloud concepts, since students appear to have verbally a better understanding of the electron cloud than the orbital, whereas the opposite holds true for their pictorial representations. Comparing verbal and pictorial representations, the pictorial ones appear to be more consistent tools, whereas a quantum context defined by n = 2 seems to be more challenging for students compared to that of n = 1. Furthermore, an analysis of student profiles leads to their categorization in four classes, providing additional relevant information. Implications for science education are also discussed.

In chemistry and biochemistry, chirality represents the structural asymmetry characterized by nonsuperimposable mirror images for a material such as DNA. In physics, however, chirality commonly refers to the spin–momentum locking of a particle or quasiparticle in the momentum space. While seemingly disconnected, structural chirality in molecules and crystals can drive electronic chirality through orbital–momentum locking; that is, chirality can be transferred from the atomic geometry to electronic orbitals. Electronic chirality provides an insightful understanding of chirality-induced spin selectivity, in which electrons exhibit salient spin polarization after going through a chiral material, and electrical magnetochiral anisotropy, which is characterized by diode-like transport. It further gives rise to new phenomena, such as anomalous circularly polarized light emission, in which the light handedness relies on the emission direction. These chirality-driven effects will generate broad impacts for fundamental science and technology applications in spintronics, optoelectronics, and biochemistry. [ABSTRACT FROM AUTHOR]

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For a safe sclerotherapy session to be completed in the orbital low-flow malformation (namely lymphovenous malformation or venolymphatic malformation), accurate identification of the target lesion for the drug injection is crucial. Regarding the dependability and viability of the injection approach, the authors have discussed their experiences with image-guided percutaneous sclerotherapy on a few patients. [ABSTRACT FROM AUTHOR]

This contribution gives basic information about the mechanical behavior of the facial part of the human skull cranium, i.e., the splanchnocranium, associated with external loads and injuries caused mainly by brachial violence. The main areas suffering from such violence include the orbit, frontal, and zygomatic bones. In this paper, as a first approach, brachial violence was simulated via quasi-static compression laboratory tests, in which cadaveric skulls were subjected to a load in a testing machine, increasing till fractures occurred. The test skulls were also used for research into the dynamic behavior, in which experimental and numerical analyses were performed. A relatively high variability in forces inducing the fractures has been observed (143–1403 N). The results lay the basis for applications mainly in forensic science, surgery, and ophthalmology. [ABSTRACT FROM AUTHOR]

PURPOSE: The purpose of this study was to determine the role of transcutaneous retrobulbar amphotericin B (TRAMB) injection in COVID-19-related rhino-orbital-cerebral mucormycosis (ROCM). MATERIALS AND METHODS: This prospective interventional case series included 7 eyes of 7 patients diagnosed with COVID-19 ROCM presenting from May to September 2021 at a tertiary care center in North India. Active or recovered cases of COVID-19 with clinical features suggestive of ROCM and early orbital involvement were included. Following functional endoscopic sinus surgery, patients were given TRAMB 3.5 mg/ml in single ocular quadrant depending upon the muscle involved on contrast-enhanced magnetic resonance imaging (MRI). Patients were followed up for a period of 12 weeks. RESULTS: All patients were diabetic and COVID-19 reverse transcription-polymerase chain reaction positive. The mean age of patients was 48.4 years ± 11 years, out of which 5 patients were male and 2 were female. The left eye was involved in 57.14% of cases whereas 42.85% of cases had right eye involvement. Presenting complaints were drooping of the upper lid (57.14%; n = 4), proptosis (28.57%; n = 2), facial pain and swelling (85.71%; n = 6), and nasal block (57.14%; n = 4). Stagewise distribution was 3a in four patients (57.14%), 3b in two patients (28.57%), and 4a in one patient. TRAMB injections (median - 3) were given, and improvement was seen in all patients in terms of ocular movements, ptosis, proptosis, and muscle enhancement on MRI scan. Three patients had an increase in intraocular pressure and inflammation which settled within a week with favorable anatomical and functional outcomes. CONCLUSION: Transcutaneous retrobulbar amphotericin B should be considered an adjunctive treatment modality for ROCM patients with limited orbital disease to preserve ocular function. [ABSTRACT FROM AUTHOR]

Abstract This epidemiological study examined ocular and orbital lymphomas in the United States from 1995 to 2018, using data from the North American Association of Central Cancer Registries database of 87,543 patients with ocular and adnexal malignancies. We identified 17,878 patients (20.4%) with ocular and orbital lymphomas, with an age-standardized incidence rate (ASIR) of 2.6 persons per million (ppm). The incidence was the highest in the orbit (ASIR = 1.24), followed by the conjunctiva (ASIR = 0.57). Non-Hodgkin B-cell lymphoma was the most prevalent subtype (85.4%), particularly marginal-zone lymphoma (45.7%). Racial disparities were noted, with Asia–Pacific Islanders showing the highest incidence (orbit, 1.3 ppm). The incidence increased significantly from 1995 to 2003 (Average Percent Change, APC = 2.1%) but declined thereafter until 2018 (APC = − 0.7%). 5-year relative survival (RS) rates varied, with the highest rate for conjunctival lymphoma (100%) and the lowest for intraocular lymphoma (70.6%). Survival rates have generally improved, with an annual increase in the 5-year RS of 0.45%. This study highlights the changing epidemiological landscape, pointing to initial increases and subsequent decreases in incidence until 2003, with survival improvements likely due to advancements in treatment. These findings underscore the need for further research to investigate the root causes of these shifts and the declining incidence of ocular lymphoma.

Cholesterol Granuloma is a rare lesion which occurs at locations like ear, peritoneum, lungs, breast etc. and formed due to interaction of Cholesterol and living tissue. But Cholesterol Granuloma occurring in the orbit is a very rare entity and so we authors present a case of Cholesterol Granuloma of the orbit. [ABSTRACT FROM AUTHOR]

Celestial navigation is rarely seen in modern Uncrewed Aerial Vehicles (UAVs). The size and weight of a stabilized imaging system, and the lack of precision, tend to be at odds with the operational requirements of the aircraft. Nonetheless, celestial navigation is one of the few non-emissive modalities that enables global navigation over the ocean at night in Global Navigation Satellite System (GNSS) denied environments. This study demonstrates a modular, low cost, lightweight strapdown celestial navigation solution that is utilized in conjunction with Ardupilot running on a Cube Orange to produce position estimates to within 4 km. By performing an orbit through a full rotation of compass heading and averaging the position output, we demonstrate that the biases present in a strapdown imaging system can be nullified to drastically improve the position estimate. Furthermore, an iterative method is presented which enables the geometric alignment of the camera with the Attitude and Heading Reference System (AHRS) in-flight without an external position input. The algorithm is tested using real flight data captured from a fixed wing aircraft. The results from this study offer promise for the application of low cost celestial navigation as a redundant navigation modality in affordable, lightweight drones.

This epidemiological study examined ocular and orbital lymphomas in the United States from 1995 to 2018, using data from the North American Association of Central Cancer Registries database of 87,543 patients with ocular and adnexal malignancies. We identified 17,878 patients (20.4%) with ocular and orbital lymphomas, with an age-standardized incidence rate (ASIR) of 2.6 persons per million (ppm). The incidence was the highest in the orbit (ASIR = 1.24), followed by the conjunctiva (ASIR = 0.57). Non-Hodgkin B-cell lymphoma was the most prevalent subtype (85.4%), particularly marginal-zone lymphoma (45.7%). Racial disparities were noted, with Asia–Pacific Islanders showing the highest incidence (orbit, 1.3 ppm). The incidence increased significantly from 1995 to 2003 (Average Percent Change, APC = 2.1%) but declined thereafter until 2018 (APC = − 0.7%). 5-year relative survival (RS) rates varied, with the highest rate for conjunctival lymphoma (100%) and the lowest for intraocular lymphoma (70.6%). Survival rates have generally improved, with an annual increase in the 5-year RS of 0.45%. This study highlights the changing epidemiological landscape, pointing to initial increases and subsequent decreases in incidence until 2003, with survival improvements likely due to advancements in treatment. These findings underscore the need for further research to investigate the root causes of these shifts and the declining incidence of ocular lymphoma. [ABSTRACT FROM AUTHOR]

A previously healthy adult male presented with a slowly enlarging orbital mass associated with 5 mm of non-pulsatile proptosis. On imaging, a soft tissue lesion with avid contrast enhancement and associated bony hyperostosis was noted. The lesion and hyperostotic bone were surgically debulked, and significant arterial bleeding was noted intraoperatively consistent with an arteriovenous malformation. Histopathologic analysis revealed a vascular malformation with enhanced microvasculature infiltrating the periosteum. While vascular lesions elsewhere in the body can be associated with skeletal changes, bony hyperostosis is a rare feature of orbital vascular malformations. [ABSTRACT FROM AUTHOR]

Background: Ocular lymphomas are rare, indolent tumours that pose a diagnostic challenge. Patients may be asymptomatic or present with symptoms of increased orbital mass. An index of suspicion is required alongside an understanding of the diagnostics and staging required to facilitate expedited multi-disciplinary work-up and management. Methods: A comprehensive literature review was performed. We present a series of three cases, each presenting their own diagnostic challenge. Results: Although ocular lymphomas are notoriously difficult to diagnose histologically, our case series show procurement of a diagnostic histological sample using an image-guided endoscopic sinus approach. Conclusions: Although not typically involved in the diagnosis or management, the otolaryngologist may encounter ocular lymphoma masquerading as sinus disease or with disseminated disease at other sites in the head and neck. Endoscopic sinus surgery is considered a safe, effective approach for achieving a histological diagnosis in these cases. [ABSTRACT FROM AUTHOR]

The study investigates secondary students’ understanding of “orbital” and “electron cloud” concepts in different quantum contexts (for values of the ʽprincipal quantum number n = 1 and n = 2) on the basis of their verbal and pictorial representations, evaluating also their consistency. Participants, which were 192 12th-grade students from six urban secondary schools of Northern Greece, represented these two concepts through two corresponding tasks of a paper-and-pencil assessment tool, each of which comprised two parts for verbal and pictorial representations, respectively. Results provide evidence that although students struggle to express verbally the orbital and electron cloud concepts, their competences in the corresponding pictorial representations are relatively better, exhibiting inconsistencies between verbal and pictorial representations. Inconsistencies also exist between representations of the orbital and electron cloud concepts, since students appear to have verbally a better understanding of the electron cloud than the orbital, whereas the opposite holds true for their pictorial representations. Comparing verbal and pictorial representations, the pictorial ones appear to be more consistent tools, whereas a quantum context defined by n = 2 seems to be more challenging for students compared to that of n = 1. Furthermore, an analysis of student profiles leads to their categorization in four classes, providing additional relevant information. Implications for science education are also discussed. [ABSTRACT FROM AUTHOR]

The objective of this study is to describe causative pathogens and current antibiotic management among hospitalized children with orbital cellulitis. This retrospective study, performed at a tertiary care children's health system, included patients up to 18 years old who presented with radiographic evidence of orbital cellulitis from 2012 to 2019. Of the 298 patients included in the study, 103 had surgery and an intraoperative culture obtained. A pathogen was recovered in 86 cultures (83.5%). The most common pathogens were Streptococcus anginosus group (26.2%), Streptococcus pyogenes (11.7%), methicillin-susceptible Staphylococcus aureus (10.7%), and Streptococcus pneumoniae (9.7%). Only 8/194 (4.1%) blood cultures returned positive. Median duration of intravenous antibiotics was 4 days and median total duration was 17 days. The most common empiric regimen prescribed was ceftriaxone and clindamycin (64.1%). Despite low incidence of methicillin-resistant S aureus, empiric antibiotics often consisted of 2 antibiotics to ensure coverage for this bacterium. [ABSTRACT FROM AUTHOR]

A 2-year-old boy presented with left periorbital edema, proptosis, hyperglobus and esotropia. Imaging revealed an inferotemporal orbital mass with adjacent bony erosion. Histological evaluation of an orbital biopsy revealed B-cell acute lymphoblastic leukemia/lymphoma (B-ALL/BLL). The patient was subsequently treated with chemotherapy. Although orbital involvement in acute myelogenous leukemia has been well-described, orbital manifestations of B-ALL/BLL are uncommon, with only a limited number of previous reports in the literature. [ABSTRACT FROM AUTHOR]

Background: Crystal-storing histiocytosis (CSH) is a rare disorder which most commonly occurs in the setting of concurrent lymphoproliferative disease. Morphologically, it consists of aggregates of histiocytes containing eosinophilic crystalline material, which in most cases is composed of aggregated abnormal light chains. Methods: Using histomorphology, immunohistochemistry and in situ hybridization, the authors characterize a rare case of orbital CSH associated with extranodal marginal zone (MALT) lymphoma and report for the first time the frozen section features of CSH. Results: The frozen section featured plump histiocytes with ample weakly basophilic to grayish cytoplasm with a microvacuolated appearance and focal stippling. These features stand in contrast with the formalin-fixed, paraffin embedded histomorphological appearance of aggregates of plump histiocytes with densely eosinophilic crystalline cytoplasmic material. Conclusion: CSH is a challenging diagnosis to make on frozen section. The artifacts that preclude its recognition, as well as differential diagnoses of this entity in the head and neck are discussed. [ABSTRACT FROM AUTHOR]

AIM: To analyze the 5-year disease-free survival (DFS) of primary orbital lymphoma (POL) by clinical characteristics and imaging features. METHODS: A total of 72 patients, 43 males and 29 females, with histologically confirmed POL, were retrospectively recruited between January 2012 and May 2017. The information on clinical characteristics, imaging features, and 5-year DFS was obtained. Univariate and multivariate forward logistic regression analyses were used to identify the variables significantly associated with 5-year DFS. Kaplan-Meier was applied for survival analysis. RESULTS: Univariate analysis revealed that uni- or bilateral orbital involvement, single or multiple lesions, treatment methods, and contrast enhancement pattern on images were significant for 5-year DFS (P=0.022, 0.042,