This document provides a summary of CT scans of the orbit and surrounding structures with corresponding diagrams. It includes axial, coronal, and sagittal CT scans at different levels through the orbit, labeled with key anatomical structures visible in each scan such as muscles, bones, sinuses, blood vessels and nerves. Diagrams accompany each scan identifying the structures. The document aims to familiarize readers with cross-sectional anatomy of the orbit and surrounding areas.

1. By
Dr. Akshymaa Moustafa
Ophthalmology specialist

4. Globe Optic nerve

5. Intraconal space
Extraconal space

9. Sagital Rt CT Sagital LT CT

12.  a Axial CT of the inferior orbit. b Corresponding diagram: 1.4 = lacrimal sac/fossa, 3.12 =
sphenoid sinus, 10.1 = inferior rectus muscle, 10.6 = insertion of inferior oblique muscle.

13.  c Corresponding bone window, d corresponding diagram: 2.1 = nasal septum, 2.5 =
ethmoid sinus, 2.6 = middle turbinate (concha), 4 = zygomatic bone, 3.10 = oval
foramen (foramen ovale), 3.12 = sphenoid sinus, 3.13 = pterygo-palatine fossa, 11.4 =
temporal bone, 14.1 = carotid canal

14.  a Axial CT at the inferior region of the orbit. b Corresponding diagram: 3.7 =
inferior orbital fi ssure, 3.12 = sphenoid sinus, 4.2 = temporal fossa, 9.1 = lens,
9.3 = sclera, 10.1 = inferior rectus muscle, 14.2 = internal carotid artery (ICA).

15.  c Corresponding bone window. d Corresponding diagram: 3.7 = inferior orbital fi ssure, 3.8
= great wing of the sphenoid bone, 4 = zygomatic bone, 8 = petrous bone, 11.4 = temporal
bone

16.  a Axial midorbital CT. b Corresponding diagram: 9.3 = sclera, 9.7 = vitreous body, 10.2 =
medial rectus muscle, 10.4 = lateral rectus muscle, 10.11 = optic nerve, 10.15 = lacrimal
gland, 13.1 = temporal lobe, 13.11 = pituitary gland.

17.  c Corresponding bone window, d corresponding diagram: 3.4 =dorsum sellae, 3.6 =
superior orbital fi ssure, 3.8 = great wing, 3.12 = sphenoid sinus, 4 = zygomatic bone.

18.  a Axial CT at the level of the optic nerve. b Corresponding diagram: 10.2 = medial rectus
muscle, 10.4 = lateral rectus muscle, 10.11 = optic nerve, 10.15 =lacrimal gland, 13.11 =
pituitary gland, 13.28 = mesencephalic (ambient) cistern.

19.  c Corresponding bone window, d corresponding diagram: 3.1 = anterior clinoid process, 3.2
= optic canal, 3.6 = superior orbital f i ssure, 3.8 = great wing of the sphenoid bone, 3.12=
sphenoid sinus, 4 = zygomatic bone.

20.  a Axial CT of the superior region of the orbit. b Corresponding diagram: 7.6 = olfactory
groove, 10.8 = trochlea, 10.11 = optic nerve (in 3.2 = optic canal), 10.13 = superior ophthalmic
vein, 10.15 = lacrimal gland, 13.1 = temporal lobe, 14.2 = ICA (internal carotid artery).

21.  c Corresponding bone window. d Corresponding diagram: 2.4 = crista galli, 3.1 = anterior
clinoid process, 3.2 = optic canal, 3.4 = dorsum sellae, 3.12 = sphenoid sinus, 7.2 = frontal
sinus.

22.  a Axial CT of the superior orbit. b Corresponding diagram: 2.4 = crista galli, 7.2 =
frontal sinus, 10.3 = superior rectus muscle, 10.5 = superior oblique muscle, 13.1 =
temporal lobe, 13.2 = frontal lobe (gyrus rectus), 14.5 = (top of the) basilar artery, 14.7 =
(p1 segment of the) posterior cerebral artery (PCA).

23.  c Corresponding bone window. d Corresponding diagram: 3.2 = optic canal, 7.2 = frontal
sinus.

24.  a Axial CT of the infraoptic region. b Corresponding diagram: 10.2 = medial rectus
muscle,10.4 = lateral rectus muscle, 10.14 = ophthalmic artery, 10.15 = lacrimal gland, 14.2
= ICA.

26.  Coronal CT (bone window) at the dorsal opening of the optic canal. b Corresponding
diagram: 2.1 = nasal septum, 2.6 = middle turbinate, 2.7 = inferior turbinate, 3.1 = anterior
clinoid process, 3.9 = round foramen, 3.12 = sphenoid sinus, 3.13 = pterygopalatine fossa,
3.14 = pterygopalatine canal, 4 = zygomatic bone, 6 = mandibular bone.

27.  a Coronal CT at the level of the optic canal. b Corresponding diagram: 1.2 = maxillary sinus, 3.2
= optic canal with optic nerve, 3.6 = superior orbital fi ssure, 3.13 = pterygopalatine fossa.

28.  c Corresponding bone window. d Corresponding diagram: 1.2 = maxillary sinus, 2.6 = middle
turbinate, 2.7 = inferior turbinate, 3.1 = anterior clinoid process, 3.2 = optic canal, 3.11 =
sphenoid plane, 3.12 = sphenoid sinus, 3.14 = pterigopalatine canal, 3.16 = sphenopalatine
foramen, 11.4 = temporal bone.

29.  a Coronal CT at the orbital apex. b Corresponding diagram: 1.2 = maxillary sinus, 11.1 =
anterior cranial fossa, 11.2 = middle cranial fossa.

30.  c Corresponding bone window. d Corresponding diagram: 1.2 = maxillary sinus, 2.5 =
ethmoid sinus, 3.7 = inferior orbital fi ssure, 11.2 = temporal lobe.

31.  a Coronal CT at the midorbital region. b Corresponding diagram: 10.1 = inferior rectus muscle,
10.2 = medial rectus muscle, 10.3 = superior rectus muscle, 10.4 = lateral rectus muscle, 10.5 =
superior oblique muscle, 10.7 = levator palpebrae muscle, 10.11 = optic nerve, 10.14 = ophthalmic
artery.

32.  c Corresponding bone window. d Corresponding diagram: 1.2 = maxillary sinus, 2.5 =
ethmoid sinus, 2.6 = middle turbinate, 2.7 = inferior turbinate, 3.8 = great wing of the
sphenoid sinus, 4 = zygomatic bone, 7 = frontal bone, 7.1 = orbital roof, 11.1 = anterior
cranial fossa

33.  Coronal CT at the level of the posterior globe. b Corresponding diagram: 1.2 = maxillary sinus,
2.6 = middle turbinate, 2.7 = inferior turbinate, 9.3 = sclera, 9.7 = vitreous body, 10.2 = medial
rectus muscle, 10.3 = superior rectus muscle, 10.5 = superior oblique muscle, 10.7 = levator
palpebrae muscle, 10.15 = lacrimal gland, 10.16 = intermuscular septum.

34.  c Corresponding bone window. d Corresponding diagram: 1.1 = infraorbital foramen (NV2),
2.1 = nasal septum, 2.5 = ethmoid sinus, 4.1 = fronto-zygomatic suture, 7.1 = orbital roof,
7.6 = olfactory groove.

35.  a Coronal CT at the region anterior orbit. b Corresponding diagram: 1.4 = lacrimal sac/fossa,
9.1 = lens (partial volume), 9.3 = sclera, 9.7 = vitreous body, 10.1 = inferior rectus muscle, 10.2
= (tendon of the) medial rectus muscle, 10.6 = inferior oblique muscle, 10.15 = lacrimal gland.

36.  c Corresponding bone window. d Corresponding diagram: 1.2 = maxillary sinus, 1.3 =
nasolacrimal duct, 2.4 = crista galli, 2.6 = middle turbinate, 2.7 = inferior turbinate, 7 =
frontal bone, 7.1 = orbital roof.