VI Venous Dural Sinuses

A.Superior Sagittal Sinus receives blood from the bridging veins and emissary veins (a potential route for transmission of extracranial infection into the brain). The superior sagittal sinus also receives cerebrospinal fluid (CSF) through the arachnoid villi.

B.Cavernous Sinus contains CNs III, IV, V1 and V2, and VI and the postganglionic sympathetic fibers. It also contains the siphon of the internal carotid artery (Figure 4-4).

VII Angiography

A.Carotid Angiography. Figure 4-5A,B shows the internal carotid artery, anterior cerebral artery, and middle cerebral artery.

B.Vertebral Angiography. Figure 4-5C,D shows the vertebral artery, PICA and AICA, basilar artery, superior cerebellar artery, and posterior cerebral artery (Figures 4-6 and 4-7).

C.Veins and Dural Sinuses. Figure 4-7 shows the internal cerebral vein, superior cerebral veins, great cerebral vein, superior ophthalmic vein, and major dural sinuses.

D.Digital Subtraction Angiography. See Figures 4-8 to 4-11.

VIII The Middle Meningeal Artery, a branch of the maxillary artery,

enters the cranium through the foramen spinosum. It supplies most of the dura, including its calvarial portion. Laceration results in epidural hemorrhage (hematoma) (Figures 4-12 and

4-13). A classic “lucid interval” is seen in 50% of cases.

Callosomarginal artery of ACA

Pericallosal artery of ACA

Cavernous ICA

Petrous ICA

Cervical ICA

Figure 4-8 Carotid angiogram, lateral projection. Identify the cortical branches of the anterior cerebral artery (ACA) and middle cerebral artery (MCA). Follow the course of the internal carotid artery (ICA). Remember that aneurysms of the posterior communicating artery (PCoM) may result in third-nerve palsy. The paracentral lobule is irrigated by the callosomarginal artery.

Figure 4-9 Carotid angiogram, anteroposterior projection. Identify the anterior cerebral artery (ACA), middle cerebral artery (MCA), and internal carotid artery (ICA). The horizontal branches of the MCA perfuse the basal nuclei and internal capsule. ACoM, anterior communicating artery.

Posterior choroidal arteries

Parieto-occipital branches of PCA

PCA, P1 segment

Calcarine branches

of PCA

Thalamoperforating

arteries

Hemispheric branches

Superior cerebellar artery

PICA

Basilar artery

Vertebral artery

Vertebral artery

Figure 4-10 Vertebral angiogram, lateral projection. Two structures are found between the posterior cerebral artery (PCA) and the superior cerebellar artery (SCA): the tentorium and the third cranial nerve. PCoM, posterior communicating artery; PICA, posterior inferior cerebellar artery.

Calcarine artery of PCA

PCA

Temporal branches

of PCA

Superior cerebellar artery

Basilar artery

PICA

Vertebral artery

Figure 4-11 Vertebral angiogram, anteroposterior projection. Which artery supplies the visual cortex? The calcarine artery, a branch of the posterior cerebral artery (PCA). Occlusion of the PCA (calcarine artery) results in a contralateral homonymous hemianopia, with macular sparing. PICA, posterior inferior cerebellar artery.

CASE 4-1

A 62-year-old man comes to the clinic complaining of problems with his vision and a horrible headache that began earlier in the day. He reports bumping into objects and not being able to read half the printed page of the newspaper. He has a history of hypertension and diabetes mellitus. What is the most likely diagnosis?

Relevant Physical Exam Findings

●Complete hemianopia

●Contralateral face and limb sensory loss

Relevant Lab Findings

●Computed tomography scan of the brain determined the presence of ischemic infarction with hemorrhagic change.

Diagnosis

● Posterior cerebral artery infarct