MyMedR

Fulltext Near-zero metamaterial inspired UHF antenna for nanosatellite communication system

Alam T, Islam MT, Cho M

Sci Rep, 2019 Mar 05;9(1):3441.

PMID: 30837629 DOI: 10.1038/s41598-019-40207-3

Epsilon-and-mu-near-zero (EMNZ) metamaterial structure inspired UHF antenna for nanosatellite has been proposed in this paper. The antenna consists of 3 × 2-unit cell array on the ground plane and a meander line radiating patch. Coaxial probe feeding technique has been obtained to excite the antenna. The meander line enables the antenna to resonate at lower UHF band and the metamaterial array is used to make the resonant frequency stable by reducing the coupling effect with metallic nanosatellite structure. The metamaterial structure exhibits EMNZ characteristics from 385 MHz to 488.5 MHz, which facilitates stable resonant frequency and higher antenna efficiency when embedded with nanosatellite structure. The proposed EMNZ inspired antenna has achieved measured impedance bandwidth (S11 orbit nanosatellite communications.

Matched MeSH terms: Orbit

Non-syndromic craniosynostosis treated by frontal orbital advancement: A case report

Khoo KW, Arman Zaharil MS, Mohd Ali MZ

Med J Malaysia, 2018 12;73(6):423-424.

PMID: 30647221

Craniosynostosis is a premature pathologic fusion of one or more cranial vault sutures leading to abnormally-shaped skull. It can occur in isolated event (non-syndromic), or it can occur in conjunction with other anomalies in welldefined patterns (syndromic). The diagnosis rests on clinical examination and confirmation is generally on the computed tomography scan. The need for surgery is both for cosmetic and functional reasons. Here we describe a case of nonsyndromic craniosynostosis that was treated with frontal orbital advancement (FOA). The potential benefits of FOA need to be carefully weighed against the potential complications when deciding for any surgical intervention.

Matched MeSH terms: Orbit/surgery*

Fulltext Orbital cellulitis from untreated conjunctival wound

Aimy Mastura, Z.Y., Norshamsiah, M.D., Hazlita, M.I., Othmaliza, O., Ropilah A.R.

Medicine & Health, 2017;12(1):94-98.

MyJurnal

Selulitis orbital merupakan jangkitan tisu di sekitar mata di dalam ruangan orbit yang
termasuk saraf mata. Ia boleh menyebabkan komplikasi yang membawa kematian
sekiranya merebak melalui saraf mata dan ke otak. Penyebab utama jangkitan
adalah termasuk perebakan jangkitan sinusitis dari ruangan paranasal atau melalui
selulitis preseptal. Kes ini menggambarkan jangkitan di luar kebiasaan mengenai
jangkitan orbital selulitis yang berlaku akibat luka torehan pada konjunktiva mata
yang disebabkan oleh kemalangan. Rawatan antibiotik sistemik yang agresif
mengurangkan risiko komplikasi penglihatan. Kesemua luka pada atau sekelililng
mata haruslah dirawat dengan sebaiknya bagi mengelakkan berlakunya komplikasi
yang membahayakan.

Matched MeSH terms: Orbit

Fulltext Sensitive dependence on initial conditions for an example of markov map: skewed doubling map

Ummu Atiqah Mohd Roslan

MATEMATIKA, 2018;34(1):13-21.

MyJurnal

Markov map is one example of interval maps where it is a piecewise expanding
map and obeys the Markov property. One well-known example of Markov map is the
doubling map, a map which has two subintervals with equal partitions. In this paper, we
are interested to investigate another type of Markov map, the so-called skewed doubling
map. This map is a more generalized map than the doubling map. Thus, the aims of this
paper are to find the fixed points as well as the periodic points for the skewed doubling
map and to investigate the sensitive dependence on initial conditions of this map. The
method considered here is the cobweb diagram. Numerical results suggest that there exist
dense of periodic orbits for this map. The sensitivity of this map to initial conditions is
also verified where small differences in initial conditions give different behaviour of the
orbits in the map.

Matched MeSH terms: Orbit

Fully Endoscopic Supraorbital Approach for Anterior Cranial Base Meningiomas

Azab WA, Najibullah M, Shabbir Z, Alali F, Yousef W

Adv Tech Stand Neurosurg, 2024;52:139-158.

PMID: 39017792 DOI: 10.1007/978-3-031-61925-0_11

BACKGROUND: Anterior cranial base meningiomas include those meningiomas originating from the tuberculum sellae, the planum sphenoidale, or the olfactory groove, with surgical excision being the main treatment modality for these tumors. Conventional microscopic and endoscope-assisted versions of the supraorbital keyhole approach via an eyebrow incision emerged into minimally invasive options that are frequently utilized nowadays for treating these tumors. At the early attempts of endoscope-assisted cranial surgery, it was noted that rigid endoscopes enabled overcoming the problem of suboptimal visualization when small exposures are used. The technical specifications and design of the currently available rigid endoscopes are associated with a group of unique features that define the endoscopic view and lay the basis for its superiority over the microscopic view during brain surgery. Notwithstanding, the fully endoscopic or endoscope-controlled version of the supraorbital keyhole approach is not routinely practiced by neurosurgeons, with few series published so far. In this chapter we elaborate on the surgical technique and nuances of the fully endoscopic supraorbital approach for anterior cranial base meningiomas.

METHODS: From a prospective database of endoscopic procedures maintained by the senior author, clinical data, imaging studies, operative charts, and videos of cases undergoing fully endoscopic excision of anterior cranial base meningiomas via supraorbital approach were retrieved and analyzed. The pertinent literature was also reviewed.

RESULTS: The surgical technique of the fully endoscopic supraorbital approach for anterior cranial base meningiomas was formulated.

CONCLUSION: The fully endoscopic supraorbital approach for anterior cranial base meningiomas has many advantages over the conventional procedures. In our hands, the technique has proven to be feasible, efficient, and minimally invasive with excellent results.

Matched MeSH terms: Orbit/surgery

Surgical Timing and Fracture Type on the Outcome of Diplopia After Orbital Fracture Repair

Yu DY, Chen CH, Tsay PK, Leow AM, Pan CH, Chen CT

Ann Plast Surg, 2016 Mar;76 Suppl 1:S91-5.

PMID: 26808744 DOI: 10.1097/SAP.0000000000000726

Orbital fractures and the concomitant soft tissue injuries within the bony orbit result in well-recognized complications such as diplopia and enophthalmos. Guidelines for timing and indications for surgery for achieving an optimal outcome remain elusive. This study examined the effects of timing and fracture type on the outcome of orbital fracture repair.

Matched MeSH terms: Orbit; Orbital Fractures

Anaesthesia for ophthalmic procedures in patients with thyroid eye disease

Chua AW, Kumar CM, Chua MJ, Harrisberg BP

Anaesth Intensive Care, 2020 Nov;48(6):430-438.

PMID: 33198476 DOI: 10.1177/0310057X20957018

Thyroid eye disease is an autoimmune inflammatory disorder of the orbit in adults. It causes inflammation, expansion and fibrosis of orbital fat, muscles and the lacrimal gland, leading to facial disfigurement, functional disability and, in severe cases, blindness. Overall, approximately 20% of affected patients need some form of surgical intervention requiring anaesthesia. This narrative review explores the background of thyroid eye disease, surgical procedures performed and their implications for anaesthesia. General anaesthesia is used for orbital decompression procedures, strabismus correction surgery and complex oculoplastic procedures. Local anaesthetic infiltration or regional anaesthesia under monitored anaesthesia care are the techniques most commonly employed for eyelid retraction surgery. It is important to limit the volume of local anaesthetic agent used during infiltration and continuously monitor the orbital volume and ocular pressure with a ballottement technique. In addition, the contralateral eye should be checked and, if necessary, protected against corneal exposure. Retrobulbar, peribulbar and sub-Tenon's blocks are best avoided. Topical anaesthesia has been used for some strabismus correction surgery but its use is limited to motivated and cooperative patients only.

Matched MeSH terms: Orbit

Fulltext Comet Lulin

Othman, M., Ahmad, K.

ASM Science Journal, 2008;2(2):183-183.

MyJurnal

Comet Lulin was discovered by Lin Chi-Sheng and Ye Quanzhi using the 16-inch telescope at Lulin Observatory in Nantou, Taiwan in 2007. According to Brian Marsden of the Smithsonian Astrophysical Observatory, it reached its perihelion on 10 January 2009 at a distance of 113 million
km from the Sun. It moves in a very nearly parabolic retrograde (‘backwards’ compared to the movement of the planets) orbit at an inclination of 1.6 degrees from the ecliptic (“Newfound Comet Lulin to Grace Night Skies”). http://www.space.com/spacewatch/090206-ns-cometlulin.html). It passed nearest to the Earth at a distance of 61 million km on 23 February 2009.

Matched MeSH terms: Orbit

Fulltext Comet 17P/Holmes

Othman, M., Ahmad, K.

ASM Science Journal, 2007;1(2):181-182.

MyJurnal

Comet 17P/Holmes was discovered by Edwin Holmes on 6 November 1892 while he was conducting regular observations of the Andromeda Galaxy (M31). Calculations using observation of its orbits established the perihelion date as 13 June and the orbital period as 6.9 years. The 1899 and 1906 appearances were observed, but the comet was only seen again in 1964. The comet has since been
observed on every subsequent return.

Matched MeSH terms: Orbit

Current and conductance modulation at elevated temperature in siliconand InAs-based spin field-effect transistors

Osintsev D, Sverdlov V, Makarov A, Selberherr S

Sains Malaysiana, 2013;42:205-211.

Spin field-effect transistors (SpinFETs) are promising candidates for future integrated microelectronic circuits. A SpinFET is composed of two ferromagnetic contacts (source and drain), which sandwich a semiconductor channel. Current modulation is achieved by electrically tuning the gate voltage dependent strength of the spin-orbit interaction in the semiconductor region. We investigated the properties of SpinFETs for various parameters - the band mismatch, the barrier height between the contacts and the channel and the strength of the spin-orbit coupling, for various temperatures. We demonstrated that the creation of Schottky barriers between the channel and the contacts guarantees a pronounced modulation of the magnetoresistance sufficient to open a possibility to operate SpinFETs at room temperature. We also demonstrated that silicon fins with [100] orientation exhibit a stronger dependence on the value of the spin-orbit interaction and are thus preferable for practical realization of silicon-based SpinFETs.

Matched MeSH terms: Orbit

Editorial for "Functional and Morphological Brain Alterations in Dysthyroid Optic Neuropathy: A Combined Resting-State fMRI and Voxel-Based Morphometry Study"

Othman EA

J Magn Reson Imaging, 2023 Aug;58(2):518-519.

PMID: 36420830 DOI: 10.1002/jmri.28536

Matched MeSH terms: Orbit

Fulltext An unusual entry site of an intraorbital foreign body in a child

Mallika PS, Chong YJ, Tan AK, Tang IP, Aziz S, Lee HK

Med J Malaysia, 2011 Oct;66(4):361-2.

PMID: 22299559 MyJurnal

Intraorbital foreign bodies (IOrbFB) are associated with both sight and life threatening injuries. We report a case of an IOrbFB associated with retrobulbar hemorrhage and injury of the frontal sinus in an 11 year-old boy, after history of fall from the tree. Imaging studies revealed a metallic foreign body (FB) in the orbit and fracture of the walls of the frontal sinus. The usual entry route of an IOrbFB is either through the eye or orbital walls and extremely rare through the paranasal sinuses. This is the first reported case of a FB entering the orbit through the frontal sinus.

Matched MeSH terms: Orbit/injuries*

Holoprosencephaly in neonates

Ram SP, Noor AR, Mahbar Z, Krishna TN

Int J Pediatr Otorhinolaryngol, 1994 Mar;29(1):65-71.

PMID: 8169049

A single nostril associated with alobar holoprosencephaly is a rare congenital lesion. This paper reports two female term neonates with holoprosencephaly. The first neonate asphyxiated at birth had a single nostril, hypotelorism, posterior cleft palate, inferonasal coloboma of the iris and disc and persistent tunica vasculosa lentis. The other neonate had cleft lip and palate and recurrent convulsions. Both neonates had gross motor and developmental delay. Cranial sonography and CT scan showed features consistent with alobar holoprosencephaly. Karyotyping for the first neonate and her family members was normal. Both of them were treated conservatively and supervised.

Matched MeSH terms: Orbit/abnormalities

Orbital fractures in children: 10 years' experience from a tertiary centre

Sirichai P, Anderson PJ

Br J Oral Maxillofac Surg, 2015 Dec;53(10):938-42.

PMID: 26130591 DOI: 10.1016/j.bjoms.2015.06.007

Our aim was to examine the relations between type and site of the fracture, age of the patient, and the management and outcomes, among children diagnosed with orbital fractures at the Women's and Children's Hospital, Adelaide, during a 10-year period from 1 January 2003 to 31 December 2012. The records of 41 children whose ages ranged from 8 months to 15 years were analysed. There was a male predominance (n=33). Two most common fractures were orbital floor and multiwalled fractures, with medial wall as the second most common site. The most common cause of injury was sport, more often with increasing age. In contrast, falls were more common among young children. Fractures of the orbital roof were more common among young children, all of ours being in children 10 years old or less. Lateral wall fractures were also more common among young children and declined in frequency with increasing age. In contrast, fractures of the orbital floor and medial wall can occur at any age, though those of the medial wall were more common among older children. As children grow their behaviour and activities change, and the mechanism by which they become injured also changes. Growth and development of the craniofacial skeleton lead to differences in the patterns of fractures with age. Fractures of the orbital roof and lateral wall are more common among young children, while those of the orbital floor and medial wall can occur at any age.

Matched MeSH terms: Orbit

Fulltext Surface marker-assisted for orbital navigation surgery: a dry skull study

Nazimi, A.J., Nuraudi Zafirah, A.R., Nur Syaira, I., Izhar, A.A., Muhd Fazlynizam, R.

Medicine & Health, 2020;15(1):237-249.

MyJurnal

Tujuan kajian ini adalah untuk menerokai kaedah pembantu penanda permukaan terhadap implan orbital untuk pembedahan tulang orbit. Enam tengkorak manusia dewasa kering telah digunakan dalam kajian ini. Implan orbital aluminium yang disediakan secara individu, dengan ketebalan 0.4 mm disediakan untuk lantai orbit secara bilateral. Empat penanda permukaan implan fizikal dari aspek anterior dan posterior implan yang disediakan dan diimbas secara optik. Pemeriksaan pra-pembedahan tomografi berkomputer ‘cone-beam’ (CBCT) diperolehi untuk semua lantai orbit. Data 'Digital Imaging and Communications in Medicine' (DICOM) tengkorak diambil, diimport dan direka bentuk dengan format data stereolithografi (STL) implan orbital masing-masing menggunakan iPlan CMF (Versi 3.0, BrainLab, Jerman). Teknik gabungan imej dilakukan untuk setiap tengkorak selepas pembinaan semula dengan pengambilan pos-pembedahan CBCT. Pengukuran berasaskan daripada data tomografi terhadap posisi implant kemudian dinilai di antara kedudukan implan yang direncanakan dan yang direalisasikan dalam satah sagittal dan coronal. Analisa statistik dijalankan menggunakan Statistik Statistik PASW® 18. Hasil kajian menunjukkan bahawa 38 daripada 48 penanda permukaan yang dinilai menunjukkan peningkatan ketinggian kedudukan dalam skala kecil pasca-pembedahan berbanding dengan kedudukan implan orbital maya. Semakan metrik Euclidean menunjukkan perbezaan yang kurang daripada 1.00 mm dalam semua penanda permukaan kecuali pada kawasan lej posterior dan anterior dalam penilaian satah sagittal. Kajian ini menunjukkan bahawa penempatan penanda permukaan terhadap implant orbit dalam pembedahan navigasi orbit menyumbang kepada kedudukan implan orbital secara konsisten.

Matched MeSH terms: Orbit; Orbital Implants

Fulltext Secondary mucoepidermoid carcinoma of the orbit

Siuw CP, Tan SW, Abdul Wahid AB, Vasudevan S

Indian J Ophthalmol, 2016 Mar;64(3):238-41.

PMID: 27146939 DOI: 10.4103/0301-4738.181748

A 40-year-old man presented with right eye axial proptosis and ophthalmoplegia for 3 months. Imaging study showed a right intraconal mass with the erosion of the orbital floor. Incisional biopsy revealed mucoepidermoid carcinoma. Nasal endoscopy was normal and systemic tumor screening was negative for a primary source. The patient underwent right orbital exenteration, uncinectomy, nasal and maxillary mucosal biopsy. Malignant cells were found present in the mucosa of maxillary sinus roof and uncinate bone. The postoperative positron emission tomography scan showed residual active lesion in right orbital apex and maxilla but no primary lesion elsewhere. The patient subsequently underwent 35 cycles of postoperative radiotherapy. Primary mucoepidermoid carcinoma of the orbit is rare and typically arises from the lacrimal gland or sac. Those tumors not arising from lacrimal apparatus should be presumed metastatic in origin, and the thorough systemic survey should be undertaken in the search for the primary tumor.

Matched MeSH terms: Orbit/surgery; Orbital Neoplasms/diagnosis*; Orbital Neoplasms/surgery; Orbit Evisceration

Fulltext Langerhans cell histiocytosis of maxillary sinus

Azreen AB, Kwan CY, Prepagaren N

Med J Malaysia, 2012 Dec;67(6):627-8.

PMID: 23770962 MyJurnal

Langerhan cell histiocytosis is a rare disease and usually occurs in paediatric age group. This disease may involve single or multiple organs system and has an unpredictable course of disease. The involvement of head and neck region are almost 90% of cases, however maxillary sinus involvement is very rare. We report a case of 2 year old boy presented with multi organ LCH (orbit, skull, sinus and liver). The mainstay treatment for this high risk multi organ LCH group is chemotherapy. Unfortunately, although with the advancement of treatment, their mortality rate is still high.

Matched MeSH terms: Orbit

Fulltext Co-existing of sinonasal inverted papilloma and angiofibroma: case report and review of the literature

Shahrjerdi B, Angoyaroko A, Abdullah B

Acta Inform Med, 2012 Dec;20(4):261-3.

PMID: 23378696 DOI: 10.5455/aim.2012.20.261-263

Sinonasal tumors may grow to considerable size before presentation and in view of their relation to the base of skull, orbit, cranial nerves and vital vessels; a precise diagnostic and therapeutic planning is needed to achieve the optimal results. We report a case who presented with unilateral nasal blockage, rhinorrhea and episodes of epistaxis which diagnosed as sinonasal inverted papilloma and angiofibroma.

Matched MeSH terms: Orbit

Different Intraorbital Implant Situations and Ocular Prosthetic Rehabilitation

Aggarwal H, Kumar P, Eachempati P, Alvi HA

J Prosthodont, 2016 Dec;25(8):687-693.

PMID: 26447725 DOI: 10.1111/jopr.12369

Enucleation is the removal of the entire globe of the eye and a portion of the optic nerve, while evisceration involves the removal of the contents of the globe leaving the sclera, extraocular muscles, and optic nerve. Following enucleation or evisceration, intraorbital implants are routinely placed to enhance the prosthetic outcome in addition to restoring the lost orbital volume. Current practice employs intraorbital implants made of nonporous silicone, hydroxyapatite, or porous polyethylene. Intraorbital implant selection and placement, being a highly demanding procedure in terms of knowledge, skill, and expertise, may be associated with a multiplicity of technical and surgical errors. Complications are usually minimal with these implants, but they do occur. The literature reveals many articles related to intraorbital implants, their benefits, and complications; however, the literature regarding the effect of various intraorbital implant situations on the subsequent prosthetic rehabilitation is markedly scarce. Moreover, the need for interdisciplinary surgical and prosthetic interventions required for successful rehabilitation in cases of compromised implant situations has been underemphasized. Hence, this review aimed to evaluate the effect of different intraorbital implant situations on ocular rehabilitation and the required interdisciplinary surgical and prosthetic treatment approach for rehabilitation of enucleated/eviscerated sockets with compromised implant situations, to provide a critical appraisal, and to present a simplified management strategy.

Matched MeSH terms: Orbit; Orbital Implants*

Fulltext A comparative assessment of prosthetic outcome on enucleation and evisceration in three different etiological eye defects: A case series

Jamayet NB, Kirangi JK, Husein A, Alam MK

Eur J Dent, 2017 4 25;11(1):130-134.

PMID: 28435380 DOI: 10.4103/1305-7456.202636

Enucleation and evisceration are the most common surgical procedures that are performed to manage tumor, trauma, and infection. Given the consequences of surgical intervention, the conditions of the remaining eye socket may affect future prosthetic rehabilitation. A custom-made ocular prosthesis can be used to help restore the esthetics and functional defects and to improve the quality of life of patients with such conditions. An assessment must be performed on the prosthetic outcome before rehabilitation. The etiology of defect, type of surgery, condition of the remaining socket, and patient's age should all be considered. This report discusses three different etiological eye defects that have undergone enucleation and evisceration and describes the factors that have a significant role in the esthetic and functional outcome of the prosthesis. This report should serve as a helpful aid for maxillofacial prosthodontists to understand the primary objective of rehabilitating each eye defect and to meet patient expectations.

Matched MeSH terms: Orbit

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