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Occipital artery

Giant cell arteritis (cranial or temporal arteritis) is an inflammatory condition that may affect any of the large arteries, especially the temporal and occipital arteries. The thickened temporal arteries may be tender and non-pulsatile, with erythema and oedema of the overlying skin. Early treatment with high-dose corticosteroids such as prednisolone is essential and should be continued for a minimum of 2-3 years at a reduced dose. [Pg.169]

Figure 2.4. In vivo measurement of blood-brain barrier (BBB) permeability, (a) Internal carotid artery perfusion technique (i) in the rat. Other branches of the carotid artery are ligated or electrically coagulated (o, occipital artery p, pterygopalatine artery). The external carotid artery (e) is cannulated and the common carotid artery (c) ligated. Perfusion time may range from 15 s to 10 min, depending on the test substance. It is necessary to subtract the intravascular volume, Vo, from (apparent volume of distribution), to obtain true uptake values and this may be achieved by inclusion of a vascular marker in the perfusate, for example labelled albumin. Time-dependent analysis of results in estimates of the unidirectional brain influx constant Ki (pi min which is equivalent within certain constraints to the PS product. BBB permeability surface area product PS can be calculated from the increase in the apparent volume of distribution Vd over time. Capillary depletion, i.e. separation of the vascular elements from the homogenate by density centrifugation, can discriminate capillary uptake from transcytosis. (b) i.v. bolus kinetics. The PS product is calculated from the brain concentration at the sampling time, T, and the area under the plasma concentration-time curve, AUC. Figure 2.4. In vivo measurement of blood-brain barrier (BBB) permeability, (a) Internal carotid artery perfusion technique (i) in the rat. Other branches of the carotid artery are ligated or electrically coagulated (o, occipital artery p, pterygopalatine artery). The external carotid artery (e) is cannulated and the common carotid artery (c) ligated. Perfusion time may range from 15 s to 10 min, depending on the test substance. It is necessary to subtract the intravascular volume, Vo, from (apparent volume of distribution), to obtain true uptake values and this may be achieved by inclusion of a vascular marker in the perfusate, for example labelled albumin. Time-dependent analysis of results in estimates of the unidirectional brain influx constant Ki (pi min which is equivalent within certain constraints to the PS product. BBB permeability surface area product PS can be calculated from the increase in the apparent volume of distribution Vd over time. Capillary depletion, i.e. separation of the vascular elements from the homogenate by density centrifugation, can discriminate capillary uptake from transcytosis. (b) i.v. bolus kinetics. The PS product is calculated from the brain concentration at the sampling time, T, and the area under the plasma concentration-time curve, AUC.
Verheggen R, Meier A, Werner I, et al. Functional 5-HT receptors in human occipital artery. Naunyn-Schmiedebergs Arch Pharmacol 2004 369 391-401. [Pg.535]

The external carotid artery also starts at the bifurcation. Branches supply the jaw, face, scalp, neck and meninges via the superficial temporal, facial and occipital arteries. [Pg.38]

The meninges are supplied by branches of the external carotid artery, internal carotid artery and vertebral arteries. The most prominent branches from the external carotid artery are the middle meningeal artery and tributaries of the ascending pharyngeal and occipital arteries. Most of the branches from the internal carotid artery arise near the cavernous sinus and from the ophthalmic artery in the orbit. Branches from the vertebral artery arise at the foramen magnum. There are numerous meningeal anastomoses between these small arteries. [Pg.42]

Five patients who had consumed large amounts (0.1-1 kg) of licorice subsequently had transient visual loss/ aberrations (35). Glycyrrhizinic acid in licorice causes vasoconstriction in vascular smooth muscle and the authors therefore speculated that vasospasm of the retinal or occipital artery had caused the problems. [Pg.1314]

Fig. 18.3. Final appearance of the external carotid artery. 1, occipital artery 2, ascending pharyngeal artery 3, inferior tympanic artery 4, internal carotid artery 5, lingual artery 6, facial artery 7, posterior auricular artery 8, superficial temporal artery 9, petrous branch 10, middle meningeal artery 11, maxillary artery 12, transverse facial artery... Fig. 18.3. Final appearance of the external carotid artery. 1, occipital artery 2, ascending pharyngeal artery 3, inferior tympanic artery 4, internal carotid artery 5, lingual artery 6, facial artery 7, posterior auricular artery 8, superficial temporal artery 9, petrous branch 10, middle meningeal artery 11, maxillary artery 12, transverse facial artery...
Fig. 18.2. EGA embryonic development at a later stage. 1, occipital artery 2, ascendant pharyngeal artery 3, faciolingual artery 4, maxillomandibular artery 5, supraorbital artery 6, internal carotid artery... Fig. 18.2. EGA embryonic development at a later stage. 1, occipital artery 2, ascendant pharyngeal artery 3, faciolingual artery 4, maxillomandibular artery 5, supraorbital artery 6, internal carotid artery...
The pharyngo-occipital system consist of an occipital artery, witch supplies the cutaneomuscu-lar elements and an ascending pharyngeal artery that is responsible for the meningeal and neural territory. The latter vessel is a metameric artery that has numerous anastomoses with the ICA and its branches are in hemodynamic balance with the suboccipitocervical system. [Pg.239]

Most often, the occipital artery arises from the external carotid artery, in some cases as a common trunk with the ascending pharyngeal artery. In other cases they may arise from the origin of the internal carotid artery. The occipital artery may also arise from the vertebral system via the branch of the first or the second vertebral body level or, more rarely, from the cervical arteries or from the vertebral artery at C3 level. [Pg.239]

Fig. 18.8a-d. Selective occipital angiogram in lateral view a demonstrates high-flow scalp AVM which was also supplied by branches of the ipsilateral and contralateral superficial temporal arteries and contralateral occipital artery (not shown). Following transarterial partial embolization with glue and particles of PVA into these vessels a percutaneous approach was performed b,c with injection of glue (50% NBCA/ 50% Lipiodol) resulting in complete obliteration of the AVM nidus as shown on the post embolization left external carotid angiogram d... [Pg.244]

The principal arteries that should be studied include the ipsilateral vertebral artery, the internal carotid artery, the distal external carotid, the posterior auricular, the occipital arteries and bilateral ascending pharyngeal arteries. It is important to visualize the venous drainage pattern and recognize the presence of a venous thrombosis. [Pg.252]

As in any endovascular embolization of the craniofacial region, special regards must be taken towards the multiple anastomosis channels between the ICA and the orbit, middle meningeal or occipital arteries. As was previously described, the embolization of the ascending pharyngeal artery with fluid agent may induce lower cranial nerve palsy. [Pg.252]

FIGURE 4.2 (Continued) A compliant balloon was used to perform angioplasty (c). Postangioplasty angiogram demonstrated complete recanalization of the basilar artery and its major branches (d and e). MRI performed 2 days later demonstrated only small areas of infarction in the cerebellar hemispheres (arrows—f and g) but no brainstem or occipital infarcts. [Pg.81]

Jongen JCF, Franke CL, Ramos LMP et al (2004) Direction of flow in posterior communicating artery on magnetic resonance angiography in patients with occipital lobe infarcts. Stroke 35 104-108... [Pg.222]

The posterior cerebral artery encircles the midbrain close to the oculomotor nerve at the level of the tentorium and supplies the inferior part of the temporal lobe, and the occipital lobe (Marinkovic et al. 1987). Many small perforating arteries arise from the proximal portion of the posterior cerebral artery to supply the midbrain, thalamus, hypothalamus and geniculate bodies. Sometimes a single perforating artery supplies the medial part of each thalamus, or both sides of the midbrain. In approximately 15% of individuals, the posterior cerebral artery is a direct continuation of the posterior commrmicating artery, its main blood supply then coming from the internal carotid artery rather than the basilar artery. [Pg.42]

The scalp is supplied by branches of the external carotid artery, particularly the superficial temporal, occipital and posterior auricular arteries. Above the orbit, there is a contribution from terminal branches of the ophthalmic artery. There is a rich anastomotic network between the various arteries of the scalp. [Pg.42]

Muscular branches of the vertebral artery in the neck. At positions distal to a vertebral obstruction, these muscular branches may receive blood retrogradely from occipital and ascending pharyngeal branches of the external carotid artery, or from the deep and ascending cervical arteries. In addition, anastomoses can develop between branches of the subclavian artery and external carotid artery when the common carotid artery is obstructed. [Pg.43]

Marchal G, Beaudouin V, Rioux P et al. (1996). Prolonged persistence of substantial volumes of potentially viable brain tissue after stroke. A correlative PET-CT study with voxel-based data analysis. Stroke 27 599-606 Marinkovic SV, Milisavljevic MM, Kovacevic MS et al. (1985). Perforating branches of the middle cerebral artery. Micro-anatomy and clinical significance of their intracerebral segments. Stroke 16 1022-1029 Marinkovic SV, Milisavljevic MM, Lolic-Draganic V et al. (1987). Distribution of the occipital branches of the posterior cerebral... [Pg.47]

Headache is not uncommon around the time of stroke onset. It is more often severe in primary intracerebral hemorrhage than ischemic stroke, and more often severe with posterior than anterior circulation strokes. If the headache is localized at all, it tends to be over the site of the lesion. Headache is more common in cortical and posterior circulation than lacunar infarcts (Kumral et al. 1995). Severe unilateral neck, orbital or scalp pain suggests internal carotid artery dissection, particularly if there is an ipsilateral Horner s syndrome. Severe occipital headache can occur with vertebral artery dissection. Headache is also a particular feature of venous infarcts. Unusual headache in the days before stroke would suggest giant cell arteritis or perhaps a mass lesion rather than a stroke. [Pg.121]

Tenderness of the branches of the external carotid artery (occipital, facial, superficial temporal) points towards giant cell arteritis. Tenderness of the common carotid artery in the neck can occur in acute carotid occlusion but is more Ukely to be a sign of dissection, or arteritis. Absence of several neck and arm pulses in a young person occurs in Takayasu s arteritis (Ch. 6). Delayed or absent leg pulses suggest coarctation of the aorta or, much more commonly, peripheral vascular disease. Other causes of widespread disease of the aortic arch are atheroma, giant cell arteritis, syphihs, subintimal fibrosis, arterial dissection and trauma. [Pg.127]

Diffusion-weighted MRI showing two areas of acute infarction in the left parietal and occipital regions, (b) Magnetic resonance angiography shows aberrant arterial anatomy with the posterior cerebral artery arising directly from the internal carotid artery (arrow) (c) This was confirmed on catheter angiography. [Pg.142]

The posterior cerebral artery supplies the occipital lobe and portions of the medial and inferior temporal lobe. The arterial supply of the spinal cord is derived from the vertebral arteries and the radicular arteries. The brain is supplied by the internal carotid arteries (the anterior circulation) and the vertebral arteries, which join at the pon tomedullary junction to form the basilar artery (collectively termed the posterior circulation). The brainstem is supplied by the posterior system. The medulla receives blood from branches of the vertebral arteries as well as from the spinal arteries and the posterior inferior cerebellar artery (PICA). The pons is supplied by paramedian and short circumferential branches of the basilar artery. Two major long circumferential branches are the anterior inferior cerebellar artery (AICA) and the superior cerebellar artery. The midbrain receives its arterial supply primarily from the posterior cerebral artery as well as from the basilar artery. The venous drainage of the spinal cord drains directly to the systemic circulation. By contrast, veins draining the cerebral hemispheres and brain stem drain into the dural sinuses. Cerebrospinal fluid also drains into the dural sinuses through unidirectional valves termed arachnoid villi. [Pg.21]

Factors that mimic glaucomatous visual field loss include branch retinal artery occlusion chorioretinal scars retinal areas treated by photocoagulafion or cryotherapy demyelin-afing disorders cerebrovascular accidents, tumors, or other lesions affecting the optic nerve, chiasm, optic tract, optic radiation, ancPor the remaining course of nerve fibers to the occipital cortex. Other abnormalities that could account for pseudo-glaucomatous visual field defects or vision loss include vitreous hemorrhage, proliferative retinopathy or other retinal disorders. [Pg.424]

The migraine aura of visual or sensory disturbance probably originates in the occipital or sensory cortex the throbbing headache is due to dilatation of pain-sensitive arteries outside the brain, including scalp arteries. [Pg.326]

A 44-year-old Chinese man had severe occipital headache, nausea, and vomiting during acupuncture in the posterior neck. A CT scan showed hemorrhage in the third, fourth, and lateral ventricles, and blood was found in the lumbar fluid. The problem was due to puncture of a branch of the vertebral artery at the feng fu point, which coincides with the site for performing cisternal puncture. The patient made a spontaneous full recovery within 28 days. [Pg.890]


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