The Influence of Primary Blast Wave on the Posterior Part of the Eyeball

2018 ◽  
Author(s):  
Junfei Tong ◽  
Linxia Gu
Keyword(s):  
Optic Nerve ◽  
Blast Wave ◽  
Military Service ◽  
Vision Loss ◽  
Life Experience ◽  
Three Dimensional ◽  
Posterior Part ◽  
Ocular Injury ◽  
Primary Blast ◽  
Globe Rupture

With the increasing application of improvised explosive devices, the ratio of traumatic ocular injury significantly increased in the past decades, which has become the fourth most happened injury to military deployment. The ocular injury treatment is costly and has been less effective, which influences the military service and life experience of the soldiers. With years of research on the traumatic ocular injury through experiment or computational simulations, the primary blast wave related overpressure was found to induce macular damage, globe rupture. While the influence of the primary blast wave on the posterior part of the eyeball was poorly understood, such as the optic nerve. In this work, we developed a three-dimensional computation model, which included lamina cribrosa (LC), optic nerve and cerebrospinal fluid (CSF). The strain evaluated in optic nerve was found to exceed neural tissue’s physiological loading range, which might explain the vision loss after the blast.

scholarly journals Biomechanical Evaluations of Ocular Injury Risk for Blast Loading

2017 ◽  
Vol 139 (8) ◽  
Author(s):  
Bahram Notghi ◽  
Rajneesh Bhardwaj ◽  
Shantanu Bailoor ◽  
Kimberly A. Thompson ◽  
Ashley A. Weaver ◽  
...  
Keyword(s):  
Intraocular Pressure ◽  
Injury Risk ◽  
Animal Studies ◽  
Experimental Studies ◽  
Three Dimensional ◽  
Blast Loading ◽  
Ocular Injury ◽  
Tissue Properties ◽  
Primary Blast ◽  
Combat Injuries

Ocular trauma is one of the most common types of combat injuries resulting from the exposure of military personnel with improvised explosive devices. The injury mechanism associated with the primary blast wave is poorly understood. We employed a three-dimensional computational model, which included the main internal ocular structures of the eye, spatially varying thickness of the cornea-scleral shell, and nonlinear tissue properties, to calculate the intraocular pressure and stress state of the eye wall and internal ocular structure caused by the blast. The intraocular pressure and stress magnitudes were applied to estimate the injury risk using existing models for blunt impact and blast loading. The simulation results demonstrated that blast loading can induce significant stresses in the different components of the eyes that correlate with observed primary blast injuries in animal studies. Different injury models produced widely different injury risk predictions, which highlights the need for experimental studies evaluating mechanical and functional damage to the ocular structures caused by the blast loading.

scholarly journals Removal of an Impaled Intraocular Hair Comb Following Self-inflicted Trauma

2020 ◽  
Vol 4 (1) ◽  
pp. 8-11
Author(s):  
Michele Markovitz ◽  
Jordan Hamburger ◽  
Brian Fromm ◽  
Brendan Carr ◽  
Xiao Zhang
Keyword(s):  
Visual Acuity ◽  
Foreign Body ◽  
Optic Nerve ◽  
Optic Neuropathy ◽  
Vision Loss ◽  
Ocular Trauma ◽  
Wide Spectrum ◽  
Saline Irrigation ◽  
Globe Rupture ◽  
Orbital Wall

Ocular trauma is one of the most common and vision-threatening ophthalmic presentations with a wide spectrum of complications, such as bleeding, infection, vision loss, and enucleation. A 64-year-old-male presented to the emergency department (ED) with a self-inflicted orbital penetrating injury with a hair comb. Computed tomography showed the comb traversed the medial orbit inferior to the medial rectus but did not damage the optic nerve; there were no globe or orbital wall fractures. His ocular exam was significant for a right eye afferent pupillary defect and decreased visual acuity 20/800, consistent with optic neuropathy. Primary concerns were stabilizing and removing the foreign body without causing further damage in the setting of an uncooperative patient. The comb was removed with the aid of local and systemic analgesia using gentle traction and normal saline irrigation. The patient was admitted for systemic and topical antibiotics and showed improvement in visual acuity and resolution of his optic neuropathy. This case illustrates the importance of rapid ED assessment and management of complex penetrating ocular trauma. Examination should specifically look for signs of globe rupture and optic nerve injury. Expedited foreign body removal should be managed together with an ophthalmologist with procedural sedation and broad-spectrum antibiotics to avoid further visual and infectious complications.

Management of Optic Neuritis in Ayurveda - A Special Case Report

2018 ◽  
Vol 3 (5) ◽  
Author(s):  
Dr. Harsha S. ◽  
Dr. Mamatha KV.
Keyword(s):  
Optic Nerve ◽  
Optic Neuritis ◽  
Visual Information ◽  
Vision Loss ◽  
Specific Treatment ◽  
Interesting Case ◽  
Treatment Modalities ◽  
Further Development ◽  
Special Case

The optic nerve carries visual information from your eye to your brain. Optic neuritis is when your optic nerve becomes inflamed. Optic neuritis can flare up suddenly from an infection or nerve disease. The inflammation usually causes temporary vision loss that typically happens in only one eye. Those with Optic neuritis sometimes experience pain. As you recover and the inflammation goes away, your vision will likely return. There are no direct references in our classics regarding optic neuritis but can be contemplated as a condition by name Parimlayi Timira. The specific management as such is not cited but a transcendence approach can be done with adopting the treatment which has the ability to pacify the already occurred pathology and prevent the further development of the disease. One such interesting case study on Optic neuritis is elaborated here where in specific treatment modalities (Shodana, Shamana and Kriyakalpas) played role in pacifying the condition.

scholarly journals Neuroglobin effectively halts vision loss in Harlequin mice at an advanced stage of optic nerve degeneration

2021 ◽  
pp. 105483
Author(s):  
Hélène Cwerman-Thibault ◽  
Christophe Lechauve ◽  
Vassilissa Malko-Baverel ◽  
Sébastien Augustin ◽  
Gwendoline Le Guilloux ◽  
...  
Keyword(s):  
Optic Nerve ◽  
Vision Loss ◽  
Nerve Degeneration ◽  
Advanced Stage ◽  
Optic Nerve Degeneration

The Central Nervous Control of Colour Change in the Minnow (Phoxinus Phoxinus L.)

1971 ◽  
Vol 54 (1) ◽  
pp. 83-91
Author(s):  
MICHAEL J. GENTLE
Keyword(s):  
Optic Nerve ◽  
Optic Tectum ◽  
Posterior Part ◽  
Colour Change ◽  
Complete Removal ◽  
The Other ◽  
Nervous Control ◽  
Phoxinus Phoxinus ◽  
External Conditions

1. The colour of the minnow Phoxinus phoxinus L. and its ability to undergo colour change were studied after partial and complete blinding. The blinding was accomplished either by section of the optic nerve or by tectal ablation. 2. Following bilateral section of the optic nerve the blinded minnows darken. After the initial darkening, half of the fish pale and the other half remain dark. 3. The colour of the fish blinded by bilateral section of the optic nerve could not be affected by external conditions. 4. Following complete removal of the optic tectum the fish at first paled, but after 24 h they darkened to very variable tints. 5. Unilateral section of the optic nerve coupled with unilateral tectal removal on the same or opposite side did not affect the ability of the fish to change colour. 6. The bilateral removal of the anterior tectum from a blinded darkened fish did not affect its colour. 7. The bilateral removal of the posterior tectum of a darkened fish caused maximal pallor. 8. By a series of lesions an area in the dorsal posterior part of the optic tectum was found to cause darkening in the blinded fish because following its removal the fish paled. 9. It is suggested that the fibres from the tectum may act by exciting or inhibiting the neurones of the paling centre in the anterior medulla.

scholarly journals Optic neuropathy after anterior communicating artery aneurysm clipping: 3 cases and techniques to address a correctable pitfall

2018 ◽  
Vol 128 (6) ◽  
pp. 1808-1812 ◽  
Author(s):  
Joseph R. Linzey ◽  
Kevin S. Chen ◽  
Luis Savastano ◽  
B. Gregory Thompson ◽  
Aditya S. Pandey
Keyword(s):  
Optic Nerve ◽  
Vision Loss ◽  
Treatment Options ◽  
Artery Aneurysm ◽  
Anterior Communicating Artery ◽  
Mechanical Compression ◽  
Visual Examination ◽  
Microsurgical Clipping ◽  
Complete Restoration

Brain shifts following microsurgical clip ligation of anterior communicating artery (ACoA) aneurysms can lead to mechanical compression of the optic nerve by the clip. Recognition of this condition and early repositioning of clips can lead to reversal of vision loss.The authors identified 3 patients with an afferent pupillary defect following microsurgical clipping of ACoA aneurysms. Different treatment options were used for each patient. All patients underwent reexploration, and the aneurysm clips were repositioned to prevent clip-related compression of the optic nerve. Near-complete restoration of vision was achieved at the last clinic follow-up visit in all 3 patients.Clip ligation of ACoA aneurysms has the potential to cause clip-related compression of the optic nerve. Postoperative visual examination is of utmost importance, and if any changes are discovered, reexploration should be considered as repositioning of the clips may lead to resolution of visual deterioration.

scholarly journals CUSTOMIZED GUIDE FOR FEMORAL COMPONENT POSITIONING IN HIP RESURFACING ARTHROPLASTY

2017 ◽  
Vol 25 (2) ◽  
pp. 103-106
Author(s):  
Chaturong Pornrattanamaneewong ◽  
Rapeepat Narkbunnam ◽  
Keerati Chareancholvanich
Keyword(s):  
Femoral Neck ◽  
Three Dimensional ◽  
Posterior Part ◽  
Image Intensifier ◽  
Hip Resurfacing ◽  
Three Dimensional Model ◽  
Level Of Evidence ◽  
Hip Resurfacing Arthroplasty ◽  
Femoral Neck Axis ◽  
Resurfacing Arthroplasty

ABSTRACT Objective: To prove the accuracy of a customized guide developed according to our method. Methods: This customized guide was developed from a three-dimensional model of proximal femur reconstructed using computed tomography data. Based on the new technique, the position of the guide pin insertion was selected and adjusted using the reference of the anatomical femoral neck axis. The customized guide consists of a hemispheric covering designed to fit the posterior part of the femoral neck. The performance of the customized guide was tested in eight patients scheduled for total hip arthroplasty. The stability of the customized guide was assessed by orthopedic surgeons. An intraoperative image intensifier was used to assess the accuracy. Results: The customized guide was stabilized with full contact and was fixed in place in all patients. The mean angular deviations in relation to the what was planned in anteroposterior and lateral hip radiographs were 0.5º ± 1.8º in valgus and 1.0º ± 2.4º in retroversion, respectively. Conclusion: From this pilot test, the authors suggest that the proposed technique could be applied as a customized guide to the positioning device for hip resurfacing arthroplasty with acceptable accuracy and user-friendly interface. Level of Evidence IV, Cases Series.

scholarly journals School Life Experience of Male Nursing Students Reinstated at School after Military Service

2018 ◽  
Vol 24 (4) ◽  
pp. 315-325
Author(s):  
Kyoung A Nam ◽  
Kyeong Hwa Kang ◽  
Seongmi Moon
Keyword(s):  
Nursing Education ◽  
Nursing Students ◽  
Professional Identity ◽  
Military Service ◽  
Life Experience ◽  
School Life ◽  
Focus Group Interviews ◽  
Group Interviews ◽  
Quality Of Nursing

Purpose: This study aimed to explore and describe the school life experience of male nursing students reinstated at school after military service. Methods: The participants in the current study were 20 male nursing students from three universities. The data were collected in focus group interviews, and an inductive content analysis was performed on the data obtained from six focus groups. Results: The content relating to the school experience of the participants was categorized into four themes: making a new start, facing challenges, trying to find one's place, and confusion about one's professional identity. Conclusion: Nursing education in Korea needs to be reconsidered, as it adheres to a gender-stereotyped identity. This study provides implications for improving the content and quality of nursing education.

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