The orbit is the bony cavity that houses the eye and its appendages. It has a quadrilateral pyramidal shape and is bounded superiorly by the frontal bone, medially by the ethmoid and lacrimal bones, inferiorly by the maxilla and floor, and laterally by the zygomatic bone. It contains the eye, extraocular muscles, blood vessels, and nerves. The thin walls provide multiple pathways between the orbit and surrounding areas like the paranasal sinuses and cranial fossae, allowing for spread of infection or tumors. Anatomical landmarks like the optic canal, superior orbital fissure, and infraorbital fissure transmit important neurovascular structures between the orbit and other areas
Orbital anatomy and orbital fracture/oral surgery courses by indian dental ac...Indian dental academy
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lefort fractures are an important set of fractures to learn among midfacial fractues which requires a thorough anatomical knowlwdge for adequate management of patient as they suffer from mild to severe aesthetic deformities in addition to functional compromise which needs to be corrected with precise knowledge and care
Orbital anatomy and orbital fracture/oral surgery courses by indian dental ac...Indian dental academy
Indian Dental Academy: will be one of the most relevant and exciting training center with best faculty and flexible training programs for dental professionals who wish to advance in their dental practice,Offers certified courses in Dental implants,Orthodontics,Endodontics,Cosmetic Dentistry, Prosthetic Dentistry, Periodontics and General Dentistry.
lefort fractures are an important set of fractures to learn among midfacial fractues which requires a thorough anatomical knowlwdge for adequate management of patient as they suffer from mild to severe aesthetic deformities in addition to functional compromise which needs to be corrected with precise knowledge and care
Orbital anatomy and trauma /certified fixed orthodontic courses by Indian den...Indian dental academy
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Orbital fracture, types, blow in fracture ,blow out fracture ,clinical features ,superior orbital fissure syndrome ,management ,complications ,reconstruction techniques ,Oculocardiac reflex
A seminar prepared during my omfs posting hours. Short points are added for easiness to study and bihart. Reference taken from Balaji and Neelima Anil Malik
Frontal sinus fractures are currently managed by various medical specialists, including otolaryngologists/head and neck surgeons, maxillofacial surgeons, plastic surgeons, and neurosurgeons. As a result, consensus does not exist regarding the timing, indications, and treatment modality of these injuries.
Naso orbital ethmoid fractures- part 2 /certified fixed orthodontic courses ...Indian dental academy
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.
Indian dental academy provides dental crown & Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit www.indiandentalacademy.com ,or call
0091-9248678078
Naso orbito-ethmoidal fractures /certified fixed orthodontic courses by Indi...Indian dental academy
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.
Indian dental academy provides dental crown & Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit www.indiandentalacademy.com ,or call
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A Comprehensive educational presentation on the fractures of the middle third of the facial skeleton.
By: Dr. Abdul Karim Sharif, MD, PGD
Ghalib University Lecturer
Kabul, Afghanistan
2015
Orbital anatomy and trauma /certified fixed orthodontic courses by Indian den...Indian dental academy
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.
Indian dental academy provides dental crown & Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit www.indiandentalacademy.com ,or call
0091-9248678078
Orbital fracture, types, blow in fracture ,blow out fracture ,clinical features ,superior orbital fissure syndrome ,management ,complications ,reconstruction techniques ,Oculocardiac reflex
A seminar prepared during my omfs posting hours. Short points are added for easiness to study and bihart. Reference taken from Balaji and Neelima Anil Malik
Frontal sinus fractures are currently managed by various medical specialists, including otolaryngologists/head and neck surgeons, maxillofacial surgeons, plastic surgeons, and neurosurgeons. As a result, consensus does not exist regarding the timing, indications, and treatment modality of these injuries.
Naso orbital ethmoid fractures- part 2 /certified fixed orthodontic courses ...Indian dental academy
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.
Indian dental academy provides dental crown & Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit www.indiandentalacademy.com ,or call
0091-9248678078
Naso orbito-ethmoidal fractures /certified fixed orthodontic courses by Indi...Indian dental academy
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.
Indian dental academy provides dental crown & Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit www.indiandentalacademy.com ,or call
0091-9248678078
A Comprehensive educational presentation on the fractures of the middle third of the facial skeleton.
By: Dr. Abdul Karim Sharif, MD, PGD
Ghalib University Lecturer
Kabul, Afghanistan
2015
Indian Dental Academy: will be one of the most relevant and exciting training center with best faculty and flexible training programs for dental professionals who wish to advance in their dental practice,Offers certified courses in Dental implants,Orthodontics,Endodontics,Cosmetic Dentistry, Prosthetic Dentistry, Periodontics and General Dentistry.
Conjunctivitis is an inflammation or swelling of the conjunctiva. The conjunctiva is the thin transparent layer of tissue that lines the inner surface of the eyelid and covers the white part of the eye. Often called "pink eye".
Explore natural remedies for syphilis treatment in Singapore. Discover alternative therapies, herbal remedies, and lifestyle changes that may complement conventional treatments. Learn about holistic approaches to managing syphilis symptoms and supporting overall health.
- Video recording of this lecture in English language: https://youtu.be/lK81BzxMqdo
- Video recording of this lecture in Arabic language: https://youtu.be/Ve4P0COk9OI
- Link to download the book free: https://nephrotube.blogspot.com/p/nephrotube-nephrology-books.html
- Link to NephroTube website: www.NephroTube.com
- Link to NephroTube social media accounts: https://nephrotube.blogspot.com/p/join-nephrotube-on-social-media.html
Anti ulcer drugs and their Advance pharmacology ||
Anti-ulcer drugs are medications used to prevent and treat ulcers in the stomach and upper part of the small intestine (duodenal ulcers). These ulcers are often caused by an imbalance between stomach acid and the mucosal lining, which protects the stomach lining.
||Scope: Overview of various classes of anti-ulcer drugs, their mechanisms of action, indications, side effects, and clinical considerations.
Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
Title: Sense of Taste
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the structure and function of taste buds.
Describe the relationship between the taste threshold and taste index of common substances.
Explain the chemical basis and signal transduction of taste perception for each type of primary taste sensation.
Recognize different abnormalities of taste perception and their causes.
Key Topics:
Significance of Taste Sensation:
Differentiation between pleasant and harmful food
Influence on behavior
Selection of food based on metabolic needs
Receptors of Taste:
Taste buds on the tongue
Influence of sense of smell, texture of food, and pain stimulation (e.g., by pepper)
Primary and Secondary Taste Sensations:
Primary taste sensations: Sweet, Sour, Salty, Bitter, Umami
Chemical basis and signal transduction mechanisms for each taste
Taste Threshold and Index:
Taste threshold values for Sweet (sucrose), Salty (NaCl), Sour (HCl), and Bitter (Quinine)
Taste index relationship: Inversely proportional to taste threshold
Taste Blindness:
Inability to taste certain substances, particularly thiourea compounds
Example: Phenylthiocarbamide
Structure and Function of Taste Buds:
Composition: Epithelial cells, Sustentacular/Supporting cells, Taste cells, Basal cells
Features: Taste pores, Taste hairs/microvilli, and Taste nerve fibers
Location of Taste Buds:
Found in papillae of the tongue (Fungiform, Circumvallate, Foliate)
Also present on the palate, tonsillar pillars, epiglottis, and proximal esophagus
Mechanism of Taste Stimulation:
Interaction of taste substances with receptors on microvilli
Signal transduction pathways for Umami, Sweet, Bitter, Sour, and Salty tastes
Taste Sensitivity and Adaptation:
Decrease in sensitivity with age
Rapid adaptation of taste sensation
Role of Saliva in Taste:
Dissolution of tastants to reach receptors
Washing away the stimulus
Taste Preferences and Aversions:
Mechanisms behind taste preference and aversion
Influence of receptors and neural pathways
Impact of Sensory Nerve Damage:
Degeneration of taste buds if the sensory nerve fiber is cut
Abnormalities of Taste Detection:
Conditions: Ageusia, Hypogeusia, Dysgeusia (parageusia)
Causes: Nerve damage, neurological disorders, infections, poor oral hygiene, adverse drug effects, deficiencies, aging, tobacco use, altered neurotransmitter levels
Neurotransmitters and Taste Threshold:
Effects of serotonin (5-HT) and norepinephrine (NE) on taste sensitivity
Supertasters:
25% of the population with heightened sensitivity to taste, especially bitterness
Increased number of fungiform papillae
Report Back from SGO 2024: What’s the Latest in Cervical Cancer?bkling
Are you curious about what’s new in cervical cancer research or unsure what the findings mean? Join Dr. Emily Ko, a gynecologic oncologist at Penn Medicine, to learn about the latest updates from the Society of Gynecologic Oncology (SGO) 2024 Annual Meeting on Women’s Cancer. Dr. Ko will discuss what the research presented at the conference means for you and answer your questions about the new developments.
Pulmonary Thromboembolism - etilogy, types, medical- Surgical and nursing man...VarunMahajani
Disruption of blood supply to lung alveoli due to blockage of one or more pulmonary blood vessels is called as Pulmonary thromboembolism. In this presentation we will discuss its causes, types and its management in depth.
micro teaching on communication m.sc nursing.pdfAnurag Sharma
Microteaching is a unique model of practice teaching. It is a viable instrument for the. desired change in the teaching behavior or the behavior potential which, in specified types of real. classroom situations, tends to facilitate the achievement of specified types of objectives.
These lecture slides, by Dr Sidra Arshad, offer a quick overview of physiological basis of a normal electrocardiogram.
Learning objectives:
1. Define an electrocardiogram (ECG) and electrocardiography
2. Describe how dipoles generated by the heart produce the waveforms of the ECG
3. Describe the components of a normal electrocardiogram of a typical bipolar leads (limb II)
4. Differentiate between intervals and segments
5. Enlist some common indications for obtaining an ECG
Study Resources:
1. Chapter 11, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 9, Human Physiology - From Cells to Systems, Lauralee Sherwood, 9th edition
3. Chapter 29, Ganong’s Review of Medical Physiology, 26th edition
4. Electrocardiogram, StatPearls - https://www.ncbi.nlm.nih.gov/books/NBK549803/
5. ECG in Medical Practice by ABM Abdullah, 4th edition
6. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
Ethanol (CH3CH2OH), or beverage alcohol, is a two-carbon alcohol
that is rapidly distributed in the body and brain. Ethanol alters many
neurochemical systems and has rewarding and addictive properties. It
is the oldest recreational drug and likely contributes to more morbidity,
mortality, and public health costs than all illicit drugs combined. The
5th edition of the Diagnostic and Statistical Manual of Mental Disorders
(DSM-5) integrates alcohol abuse and alcohol dependence into a single
disorder called alcohol use disorder (AUD), with mild, moderate,
and severe subclassifications (American Psychiatric Association, 2013).
In the DSM-5, all types of substance abuse and dependence have been
combined into a single substance use disorder (SUD) on a continuum
from mild to severe. A diagnosis of AUD requires that at least two of
the 11 DSM-5 behaviors be present within a 12-month period (mild
AUD: 2–3 criteria; moderate AUD: 4–5 criteria; severe AUD: 6–11 criteria).
The four main behavioral effects of AUD are impaired control over
drinking, negative social consequences, risky use, and altered physiological
effects (tolerance, withdrawal). This chapter presents an overview
of the prevalence and harmful consequences of AUD in the U.S.,
the systemic nature of the disease, neurocircuitry and stages of AUD,
comorbidities, fetal alcohol spectrum disorders, genetic risk factors, and
pharmacotherapies for AUD.
The prostate is an exocrine gland of the male mammalian reproductive system
It is a walnut-sized gland that forms part of the male reproductive system and is located in front of the rectum and just below the urinary bladder
Function is to store and secrete a clear, slightly alkaline fluid that constitutes 10-30% of the volume of the seminal fluid that along with the spermatozoa, constitutes semen
A healthy human prostate measures (4cm-vertical, by 3cm-horizontal, 2cm ant-post ).
It surrounds the urethra just below the urinary bladder. It has anterior, median, posterior and two lateral lobes
It’s work is regulated by androgens which are responsible for male sex characteristics
Generalised disease of the prostate due to hormonal derangement which leads to non malignant enlargement of the gland (increase in the number of epithelial cells and stromal tissue)to cause compression of the urethra leading to symptoms (LUTS
For Better Surat #ℂall #Girl Service ❤85270-49040❤ Surat #ℂall #Girls
Orbital structure
1. Orbital Structure
and It’s application
dr. Frenky R. de Jesus
National Eye Centre
Postgraduate diploma in Ophthalmology
2. Orbital structure & it’s application
Definition
The orbit is the cavity or socket of the skull in which
the eye and its appendages are situated.
DIMENSIONS
- Quadrilateral pyramid.
- Base - forwards, laterally, downwards
- Apex - optic foramen
Rim
• Horizontally: 40 mm
• Vertically: 35 mm.
• Interorbital width: 25 mm
• Extraorbital width: 100 mm
Depth
◦ Medially ≈ 42 mm ◦ Laterally ≈ 50 mm.
BOUNDED
Superiorly: Anterior cranial fossa
Medially: Nasal cavity and ethmoidal air cells
Inferiorly: Maxillary sinus
Laterally: Middle cranial fossa.
5. Orbital structure & it’s application
ROOF
• Underlies Frontal sinus and Anterior cranial fossa.
• Formed by:
๏ Frontal bone (Orbital plate)
๏ Lesser wing of Sphenoid
• Triangular
• Faces downwards, and slightly forwards
• Concave anteriorly, almost flat posteriorly
• The anterior concavity is greatest about 1.5 cm
from the orbital margin & corresponds to the
equator of the globe.
• Thin, transluscent and fragile (except the lesser
wing of the sphenoid).
6. Orbital structure & it’s application
ROOF (Landmarks)
FOSSA FOR THE LACRIMAL GLAND
LOCATION:
Behind the zygomatic process of the frontal bone
CONTENTS:
• Lacrimal gland.
• Some orbital fat (accessory fossa of Rochon- Duvigneaud)
TROCHLEAR FOSSA (FOVEA)
LOCATION:
4 mm from the orbital margin.
CONTENTS:
• Insertion of tendinous pulley of Superior Oblique.
• Sometimes surmounted by a spicule of bone (Spina
trochlearis)
• Extremely rarely trochlea completely ossified cracks easily
SURFACE ANATOMY:
Palpable just within the supero-medial angle.
7. Orbital structure & it’s application
ROOF (Landmarks)
SUPRAORBITAL NOTCH:
LOCATION:
15 mm lateral to the superomedial angle
TRANSMITS:
- Supraorbital nerve
- Supraorbital vessels
SURFACE ANATOMY:
• At the junction of lateral 2/3rd and medial 1/3rd
• About two finger breadth
OPTIC FORAMEN
LOCATION
• Lies medial to superior orbital fissure
• At the apex
• Present in the lesser wing of sphenoid
TRANSMITS
• Optic nerve with its meninges
• Ophthalmic artery
8. Orbital structure & it’s application
ROOF (Clinical Significance)
Thin & Fragile
Easily fractured by direct violence (penetrating orbital injuries)
Easily fractured by direct violence
(Penetrating orbital injury)
Frontal lobe injury
9. Orbital structure & it’s application
MEDIAL WALL
• Thinnest orbital wall.
• Formed by:
1. Frontal process of Maxilla
2. Lacrimal bone
3. Orbital plate of Ethmoid
4. Body of Sphenoid
10. Orbital structure & it’s application
MEDIAL WALL (Landmarks)
LACRIMAL FOSSA
Formed by:
• Frontal process of Maxila
• Lacrimal bone
Content
Lacrimal sac
Boundaries:
• Anterior lacrimal crest
• Posterior lacrimal crest
• Frontoethmoidal suture
• Anterior ethmoidal foramen
• Posterior ethmoidal foramen
11. Orbital structure & it’s application
MEDIAL WALL (Clinical Significance)
• Anteriorly located suture indicates predominance of lacrimal bone
• Posteriorly located suture indicates the predominance of maxillary bone
• If maxillary component is predominant, it becomes difficult to perform osteotomy to reach the sac during DCR, because
the maxillary bone is very thick.
• Medial wall extremely fragile (presence of ethmoidal air cells and nasal cavity)
• Accidental lateral displacement of medial wall- traumatic hypertelorism
• Medial wall provides alternate access route to the orbit through the sinus
Ethmoid
• Thinnest bone of the orbit
• Vascular connections with ethmoid sinus through foramina
• Inflammation in the ethmoid sinus spreads readily to the orbit
• Tumours of the nasal cavity can breach the lamina papyracea to involve the orbit
• Lacrimal bone can be easily penetrated during endoscopic DCR
• During surgery, hemorrhage is most troublesome due to injury to ethmoidal vessels.
12. Orbital structure & it’s application
FLOOR
• Shortest orbital wall.
• Roughly triangular.
• Bordered laterally by inferior orbital fissure and medially by
maxilloethmoidal suture
• Overlies maxillary sinus.
Formed by:
• Orbital plate of maxilla (major)
• Orbital surface of Zygomatic bone (anterolateral)
• Orbital plate of Palatine bone
14. Orbital structure & it’s application
FLOOR (Clinical Significance)
BLOW OUT FRACTURE
15. Orbital structure & it’s application
LATERAL WALL
• Thickest orbital wall
• Separates orbit from
๏ Middle cranial fossa
๏ Temporal fossa
Formed by:
• Zygomatic bone
• Greater wing of sphenoid
16. Orbital structure & it’s application
LATERAL WALL (Landmarks)
LATERALORBITAL TUBERCLE OF WHITNALL:
- 4-5 mm behind the lateral orbital rim
- 11 mm inferior to the frontozygomatic suture line
Gives attachment to:
• Check ligament of lateral rectus
• Lockwood’s ligament
• Lateral canthal tendon
• The aponeurosis of the levator palpebrae superioris
• Orbital septum
• Lacrimal fascia
17. Orbital structure & it’s application
In resection of maxilla, the Whitnall’s tubercle is spared, otherwise
• Damage to Lockwood’s ligament
• Inferior dystopia of eye ball
• Diplopia
ZYGOMATIC GROOVE:
EXTENT
From the anterior end of the inferior orbital fissure to a foramen in the zygomatic bone
CONTENTS
- Zygomatic nerve
- Zygomatic vessels
• Lateral wall protects only the posterior half of the eyeball, hence palpation of retrobulbar tumours is easier.
• Frontal process of zygoma & zygomatic process of frontal bone protect the globe from lateral trauma- known as facial
buttress area.
• Just behind the facial buttress area, is the zygomaticosphenoid suture, which is the preferred site for lateral orbitotomy.
LATERAL WALL (Clinical Significance)
18. Orbital structure & it’s application
ORBITAL MARGINS
SUPERIOR ORBITAL MARGIN
• Formed by Frontal bone
• Concave downwards, convex forwards sharp in lateral
2/3rd, rounded in medial 1/3rd - at the junction-
supraorbital notch (sometimes foramen)*
*Site for nerve block.
Arnold’s notch/foramen
Present medial to supraorbital notch
Transmits
medial branches of supraorbital nerve & vessels
Supraciliary canal
Near the supraorbital notch
Transmits
• Nutrient artery
• A branch of supraorbital nerve to frontal air sinus
Surface anatomy
• Well marked prominence
• More prominent laterally than medially
• Eyebrow corresponds to the margin only in a part -
Head- under the margin
• Body- along the margin
• Tail- above the margin
19. Orbital structure & it’s application
LATERAL ORBITAL MARGIN
• Formed by zygomatic process of frontal and the
zygomatic bone.
• Strongest portion of margin.
Clinical significance
• Lateral orbital rim is recessed on its deep aspect 0.75
cm above the rim margin to accommodate the lacrimal
gland.
• Prone to fracture.
• Narrowest and weakest part- frontozygomatic suture.
• Prone for separation following blunt trauma.
ORBITAL MARGINS
INFERIOR ORBITAL MARGIN
• Formed by Zygomatic - Maxilla
• suture between the two is sometimes marked by a
tubercle- felt 4-5 mm above the infraorbital foramen
Surface anatomy
• Palpable as a sharp ridge, beyond which the finger can
pass into the orbit
Clinical significance
• At the junction of lateral 2/3rd & medial 1/3rd just within
the rim- small depression- origin of Inferior oblique
• Prone to fracture
• Disruption of Inferior oblique
• Diplopia
Penetrating injuries may severe lacrimal passages
MEDIAL ORBITAL MARGIN
Formed by Frontal process of maxilla (anterior lacrimal
crest) - Lacrimal bone (posterior lacrimal crest).
20. Orbital structure & it’s application
FISSURES AND FORAMINA
• Leads from the middle cranial fossa to the apex of the
orbit.
• Orbital opening- vertically oval.
• In the middle - circular (≈5mm)
• Intracranial - horizontally oval.
• Length; 8-12 mm
Boundaries
- Medially; Body of the sphenoid
- Laterally; Lesser wing of the sphenoid
Transmits
• Optic nerve & its meninges
• Ophthalmic artery
Optic Canal
Clinical significance: Optic nerve glioma or Meningioma may lead to unilateral enlargement of Optic canal
21. Orbital structure & it’s application
• Also known as Sphenoidal fissure
• Bounded by Lesser and greater wings of the sphenoid
• Lateral to the optic foramen at the orbital apex.
• 22 mm long.
• Largest communication between the orbit and the
middle cranial fossa.
• Its tip lies 30-40 mm from the frontozygomatic suture.
• Landmarks: annulus de zinn.
• Transmits the lacrimal, frontal, trochlear (CN IV),
oculomotor (CN III), nasociliary and abducens (CN VI)
nerves. It also carries the superior ophthalmic vein.
Superior orbital fissure
Clinical significance
• TOLOSA HUNT SYNDROME; Inflammation of the
superior orbital fissure and apex may result in a
multitude of signs including ophthalmoplegia and venous
outflow obstruction
• SUPERIOR ORBITAL SYNDROME (Rochon-Duvigneaud
syndrome)
๏Fracture at superior orbital fissure.
๏Involvement of cranial nerves
๏Diplopia, Ophthalmoplegia, Exophthalmos, Ptosis.
FISSURES AND FORAMINA
22. Orbital structure & it’s application
• Also known as sphenomaxillary fissure
• Between floor and the lateral wall
• Bounded by;
o Medially- Maxilla and orbital process of palatine
o Laterally- Greater wing of the sphenoid
o Anterior aspect- closed by Zygomatic bone
Transmits;
• Venous drainage from the inferior part of the
orbit to the pterygoid plexus
• Neural branches from the pterygopalatine ganglion
• The zygomatic nerve - the infraorbital nerve
Inferior orbital fissure
FISSURES AND FORAMINA
23. Orbital structure & it’s application
Others Pathways into the Orbit
• Transmits the optic nerve and
ophthalmic artery
• Transmits the lacrimal, frontal,
trochlear (CN IV), oculomotor
(CN III), nasociliary and
abducens (CN VI) nerves. It also
carries the superior ophthalmic
vein.
• Transmits the zygomatic branch of the
maxillary nerve, the inferior ophthalmic
vein, and sympathetic nerves
Nasolacrimal
canal • Which drains tears
from the eye to the
nasal cavity,
Supraorbital
foramen and
infraorbital canal
• They carry small
neurovascular
structures.
24. Orbital structure & it’s application
CONTENTS OF THE ORBIT
• Nerves
◦ Sensory- branches of V’th Nerve
◦ Motor- III’rd, IV’th & VI’th Nerve
◦ Autonomic- Nerves to the Lacrimal gland.
• Ciliary ganglion
• Eye ball
• Muscles
◦ 4 Recti
◦ 2 obliques
◦ Levator palpebrae superioris
◦ Muller’s muscle (Musculus orbitalis)
Vessels
•Arteries
๏Internal carotid system- branches of ophthalmic artery
๏External carotid system- a branch of internal maxillary artery
•Veins
๏Superior ophthalmic vein
๏Inferior ophthalmic vein
• Lymphatics
๏none
Lacrimal gland
Lacrimal sac
Orbital fat, reticular tissue & orbital fascia
25. Orbital structure & it’s application
Ciliary Ganglion
• Ciliary ganglion is a parasympathetic ganglion
• It measures 1-2 mm in diameter and contains 2.500
neurons.
• Lies between Optic nerve and Lateral Rectus
muscle
• The oculomotor nerve coming into the ganglion
contains preganglionic axons from the Edinger-
Westphal nucleus which form synapses with the
ciliary neurons.
• The posganglionic axons run in the short ciliary
nerves and innervate 2 muscles:
๏ The sphincter pupillae (miosis) and mydriasis.
๏ Ciliary muscle.