What is [the] most important subject you have to learn in life? To learn how to love. This is the challenge that life offers you: to learn how to love, Page 1 of 5 not just to accumulate information without knowing what to do with it; but through that love, let that information bear fruit. Pope Francis AlyssaWillisL. Ng, 1A, A.Y. 2014-2015 Far Eastern UniversityNicanor Reyes Medical Foundation Gross HSB B Scalp, Calvaria, and Meninges Dr. Capulong (Jan. 16, 2014) Scalp consists of five layers ofirst three are intimately bound together and move as a unit; use SCALP to remember the five layers S skin othick and hair bearing ocontains numerous sebaceous glands C connective tissue obeneath the skin, which is fibrofatty oa fibrous septaunites skin to the underlying aponeurosis of the occipitofrontalis muscle onumerous arteries and veins are found here arteries branches of the external and internal carotid arteries; supply the outer layer a free anastomosis takes place between them if there is injury or trauma, there is profuse bleeding because this layer/the blood vessels will not contract or will remain open A aponeurosis(Galea aponeurosis/aponeurotica [lec]) oepicranial; thin, tendinous sheet ounites the occipital and frontal bellies of the occipitofrontalis muscle (major component of muscles of facial expression) olateral margins are attached to the temporal fascia osubaponeurotic space potential space beneath the epicranial aponeuoris limited in front and behind by origins of the occipitofrontalis muscles extends laterally as far as the attachment of the temporal fascias aponeurosis L loose connective/areolar tissue ooccupies the subaponeurotic space oloosely connects the epicranial aponeurosis to the periosteum of the skull (pericranium) ocontains a few small arterires ocontains some important emissary veins valveless and connect the superficial veins of the scalp with the diploic veins of the skull bones and with the intracranial venous sinuses oprone to injury esp. if there is through and through laceration P pericranium operiosteum; covers the outer surface of the skull bones overy adherent to the cranium (outer table) oat sutures bet. individual skull bones periosteum on the outer surface becomes continuous with the periosteum on the inner surface of the skull bones

boundaries: oanterior: supraorbital margin oposterior: superior nuchal line olateral: superior temporal line blood supply oscalp has arich blood supply to nourish hair follicles reason why the smallest cut bleeds profusely oarteries lie in the superficial fascia ofrom lateral to the midline anteriorly, the ff. arteries are present: supratrochlear and supraorbital arteries branches of the ophthalmic artery ascend over the forehead in company with the supratrochlear and supraorbital nerves superficial temporal artery smaller terminal branch of external carotid artery ascends in front of the auricle in company with auriculotemporal nerve divides into anterior and posterior branches osupply skin over frontal and temporal regions posterior auricular artery branch of the external carotid artery ascends behind the auricle supply the scalp above and behind the auricle occipital artery branch of the external carotid artery ascends from apex of the posterior triangle with the greater occipital nerve supplies skin over the back of the scalp and reaches as high as the vertex of the skull nerve supply oALL of these will be sensory innervation osupratrochlear nerve branch of ophthalmic division of trigeminal nerve winds around the superior orbital margin supplies the scalp passes backward close to the median plane What is [the] most important subject you have to learn in life? To learn how to love. This is the challenge that life offers you: to learn how to love, Page 2 of 5 not just to accumulate information without knowing what to do with it; but through that love, let that information bear fruit. Pope Francis AlyssaWillisL. Ng, 1A, A.Y. 2014-2015 reaches nearly as far as the vertex of the skull osupraorbital nerve branch of ophthalmic division of trigeminal nerve winds around the superior orbital margin and ascends over the forehead supplies the scalp as far backward as the vertex ozygomaticotemporal nerve branch of the maxillary division of the trigeminal nerve supplies the scalp over the temple oauriculotemporal nerve branch of the mandibular division of trigeminal nerve ascends over the side of the head from in front of the auricle terminal branches supply skin over the temporal regioin olesser occipital nerve branch of the cervical plexus (C2) supplies scalp over the lateral part of the occipital region and skin over the medial surface of the auricle ogreater occipital nerve branch of the posterior ramus of the 2nd cervical nerve ascends over the back of the scalp supplies the skin as far forward as the vertex of the skull lymph drainage olymph vessels from anterior part of the scalp and foreheaddrain into the submandibular lymph nodes lateral part of the scalp above the earinto the superficial parotid (preauricular) nodes above and behind the eardrain into the mastoid nodes back of the scalp drain into occipital nodes Calvarium oskull cap oconsists of bone linked by sutures synarthrosis type of joint immovable all are immovable except for TMJ, which is a part of the facial bone however and not the calvariumoprotects the brain obones frontal (1) parietal (2) temporal (2) sphenoid (1) occipital (1) osuture lines coronal suture bet. frontal bone and fusion of two parietal bones bregma midpoint of coronal suture sagittal suture follows the midline bet. parietal bones lambdoidal/lambdoid suture bet. two parietal bones and occipital bone lambda midpoint of lambdoidal suture oneonatal skull fontanelles permit cranial compression during birth give movement ofor ease of fetal delivery ofor ease of pressure on CNS during delivery anterior odiamond shaped obet. two halves of the frontal bone in front and two parietal bones behind ofibrous membrane forming the floor is replaced by bone and closed by 18 months of age posterior otriangular obet. two parietal bones in front and occipital bone behind ocloses 2-3 months (lec) oclosed and can no longer be palpated by the end of 1st year (Snell) lateraloat pterion small area where there is a meeting point of parietal, temporal, frontal and sphenoid bones ointernal structure inner and outer layer hard cortical bones middle layer soft spongy bone diploodouble in Greek odiploic veins course in the diplo connect both cranial cavity and surface of skull important: can transmit infection from scalp to the brain through the emissary veins one of the reasons why you can have meningitis, 2 to open-wound injuries in the scalp What is [the] most important subject you have to learn in life? To learn how to love. This is the challenge that life offers you: to learn how to love, Page 3 of 5 not just to accumulate information without knowing what to do with it; but through that love, let that information bear fruit. Pope Francis AlyssaWillisL. Ng, 1A, A.Y. 2014-2015 meninges odura mater also known as pachymenix (G. pachy; thick + G. menix, membrane) dense, bilaminar layer closely united except along certain lines, where they separate to form venous sinuses endosteal and meningeal layer 1.endosteal layer ordinary periosteum covers inner surface of the skull bones does not extend through foramen magnum to become continuous with the dura mater of the spinal cord around the margines of all the foramina in the skull, it becomes continuous with the periosteum on the outside of the skull bones at sutures, it becomes continuous with sutural ligaments strongly adherent to the bones over the skulls base 2.meningeal layer dura mater proper strong, dense, fibrous membrane covers the brain continuous through foramen magnum with the dura mater of the spinal cord provides tubular sheaths for the cranial nerves as they pass through the skulls foramina outside the skull, the sheaths fuse with the nerves epineurium sends inward four septa odivide the cranial cavity into freely communicating spaces lodging the subdivisions of the brain ofunction: restrict rotatory displacement of the brain a.falx cerebri sickle-shaped fold lies in the midline bet. two cerebral hemispheres anterior tapers/narrow end is attached to the internal frontal crest and crista galli broad posterior part blends in the midline with upper surface of tentorium cerebelli superior sagittal sinus runs in its upper fixed margin inferior sagittal sinus runs in its lower concave free margin straight sinus runs along its attachment to tentorium cerebelli b.tentorium cerebelli crescent-shaped fold roofs over posterior cranial fossa covers upper surface of cerebellum supports occipital lobes of cerebral hemispheres tentorial notch gap in front for the passage of the midbrain; produces an inner free and outer attached border fixed border: attached to posterior clinoid process, superior borders of petrous bones, and margins of the grooves for the transverse sinuses on occipital bone free border: runs forward, crosses attached border, and attaches to anterior clinoid process at the point where the two borders cross, 3rd and 4th cranial nerves pass forward to enter the cavernous sinus (lateral wall) at apex of petrous part of temporal bone, lower layer is pouched forward beneath the superior petrosal sinus to form a recess for the trigeminal nerve and ganglion falx cerebri attached to upper surfacefalx cerebelli attached to lower surface straight sinus runs along attachment to falx cerebri superior petrosal sinus runs along attachment to petrous bone transverse sinus along attachment to occipital bone c.falx cerebelli small, sickle-shaped fold attached to the internal occipital crest and projects forward between two cerebellar hemispheres posterior fixed margin cointains occipital sinus d.diaphragma sellae small, circular fold roof for the sella turcica small opening in its center passage for the stalk of the pituitary gland dural blood supply ICA maxillary artery omiddle meningeal artery arises from this in the infratemporal fossa from a clinical standpt., this is the most important as its commonly lacerated in head trauma When you see a patient in emergency room with head trauma, check ABCs (airway, breathing, circulation) then ask for the manner of injury. This will help in localizing the injury. passes through foramen spinosum to lie between meningeal and endosteal layers of dura anterior branch deepy grooves the anteroinferior angle of parietal bone course corresponds roughly to the underlying precentral gyrus of the brain posterior branch curves backward and supplies posterior part of dura mater ascending pharyngeal artery occipital artery vertebral artery What is [the] most important subject you have to learn in life? To learn how to love. This is the challenge that life offers you: to learn how to love, Page 4 of 5 not just to accumulate information without knowing what to do with it; but through that love, let that information bear fruit. Pope Francis AlyssaWillisL. Ng, 1A, A.Y. 2014-2015 dural venous drainage meningeal veins olie in the endosteal layer oveins lie lateral to the arteries omiddle meningeal vein follows branchs of middle meningeal artery drains into pterygoid venous plexus or sphenoparietal sinus dural nerve supply trigeminal nerve vagus nerve first three cervical nerves branches from sympathetic chain all of these pass to the dura numerous sensory endings are in the dura dura is sensitive to stretching (produces sensation of headache) stimulation of dural endings oabove tentorium or cerebellumproduce pain to area of skin on the same side of the head typical headache (lec) obelow tentorium or cerebellum produces referred pain to the back of the neck and scalp along the distribution of greater occipital nerve oarachnoid delicate, impermeable membrane covers the brain lies between pia mater and dura mater bridges over the sulci on the surface of the brain subdural space potential space for bleeding separates it from dura subarachnoid space separates it from pia filled with cerebrospinal fluidremember: structures passing to and from the brain to the skull or its foramin must pass through this all cerebral arteries and veins, and cranial nerves lie here subarachnoid cisternae formed when the arachnoid and pia are widely separated arachnoid villi formed when arachnoid projects into the venous sinuses most numerous along superior sagittal sinus sites where CSF diffuses into the bloodstream arachnoid granulations oaggregations of arachnoid villi fuses with the nerves epineurium at their point of exit from the skull for optic nerve, arachnoid forms a sheath that extends into the orbital cavity through the optic canal and fuses with sclera of the eyball subarachnoid spaces extends around the optic nerve as far as the eyeball cerebrospinal fluid choroid plexuses within the lateral, third, and fourth ventricles of the brain produces CSF from the ventricles three foramina in the roof of fourth ventricle subarachnoid space upward over cerebral hemispheres and downward around the spinal cord ospinal subarachnoid space extends as far as second sacral vertebra enters the bloodstream through arachnoid villi removes waste products assoc. with neuronal activity provides a fluid medium in which the brain floats which protects the brain from trauma opia mater vascular membrane closely related to the brain covers the gyri; dips into fissures and sulci extends over cranial nerves and fuses with their epineurium enmeshes blood vessels on the surface of the brain cerebral arteries entering the substance of the brain carry a sheath of pia with them *arachnoid and pia are together called leptomeninx clinical notes (Snell 9th ed., p. 543) oIntercranial hemorrhage may result from trauma or cerebral vascular lesions 4 varieties: extradural hemorrhage oepidural type; sa labas ofrom injuries to meningeal artery or vein oant. division of middle meningeal artery most commonly damaged cause: minor blow to the lateral side of the head, resulting in fracture of the skull at the anteroinferior part of parietal bone (Snell) or temporal bone (lec) subdural hemorrhage ofrom tearing of the superior cerebral veins at their point of entrance into superior sagittal sinus ocause: blow on front or back of the head, causing excessive anteroposterior displacement of brain within the skull What is [the] most important subject you have to learn in life? To learn how to love. This is the challenge that life offers you: to learn how to love, Page 5 of 5 not just to accumulate information without knowing what to do with it; but through that love, let that information bear fruit. Pope Francis AlyssaWillisL. Ng, 1A, A.Y. 2014-2015 omore common than middle meningeal hemorrhage otwo forms (depending on speed of accumulation in the subdural space) acute massive bleeding chronic trickling type; takes several days until patient manifests increase intracranial pressure subarachnoid hemorrhage ofrom leakage or rupture of a congenital aneurysm on the circle of Willis or, less commonly, from an angioma *All are life-threatening as they can increase intracranial pressure. Speed of manifestation of signs of increase pressure: subdural hemorrhage > epidural hemorrhage cerebral hemorrhage ocause: rupture of thin-walled lenticulostriate artery, branch of middle meningeal artery oinvolves vital corticobulbar and corticospinal fibers in internal capsule venous sinuses (see Netter 6th ed., plates 104 and 105) oblood-filled spaces ofound bet. layers of dura mater olined by endothelium owallsthick and composed of fibrous tissue no muscular tissue ohave no valves oreceive blood from brain, diplo of the skull, orbit, internal ear, and emissary veins osuperior sagittal sinus upper fixed border of falx cerebri midline sinus drain the uppermost area of the brain border (ppt): anterior: foramen cecum posterior: transverse sinus receives blood from superior cerebral veins and bridging veins (emissary veins) runs backward and becomes continuous with the right transverse sinus communicates laterally with venous lacunae numerous arachnoid villi and granulations project towards lacunae oinferior sagittal sinus lower free border of falx cerebri drain middle part and posterior portion of the brain joins great cerebral vein to form the straight sinus receives cerebral veins from medial surface of cerebral hemisphere ostraight sinus at junction of falx cerebri and tentorium formed by great cerebral vein and inferior sagittal sinus drains to left transverse sinus can join superior sagittal sinus at confluence of sinuses or turn left (lec) otransverse sinus in lateral fixed part of tentorium cerebelli receives blood from superior sagittal sinus or from the confluence of sinuses (or meeting point of sinuses, specifically the sup., inf., and straight sinus) end as sigmoid sinus osigmoid sinus s-shaped continuous of transverse sinus found in both lateral ends ends in jugular foramen to continue as the internal jugular vein ooccipital sinus in the attached margin of falx cerebelli communicates with vertebral veins through foramen magnum and transverse sinuses drain into the confluence ocavernous sinus in middle cranial fossa on the lateral side of sphenoid bones body connected by intercavernous sinus through sella turcica anteriorly, receives inferior ophthalmic vein and central vein of retina drains posteriorly to transverse sinus through the superior petrosal sinus receives blood from superior and inferior ophthalmic veins and cerebral veins and drains blood to superior and inferior petrosal sinus (ppt) area is prone to thrombosis; called cavernous sinus thrombosis manifestations: visual abnormality due to compression of visual pathway one cause: abnormal blood viscosity (like uncontrolled hypertension) osuperior and inferior petrosal sinus on petrous part of temporal bone superior drains to transverse sinus inferior drains to internal jugular vein Venous sinuses summary osuperior cerebral veins and bridging veins superior sagittal sinus right transverse sinus oinferior sagittal sinus + great cerebral vein straight sinus left transverse sinus osup. sagittal sinus and confluence transverse sinus oright and left transverse sinus sigmoid sinus internal jugular vein ooccipital sinus confluenceoinferior ophthalmic vein and central vein of retina cavernous sinus superior petrosal sinus transverse sinus(Snell) OR sup. and inf. ophthalmic vein and cerebral veins cavernous sinus sup. and inf. petrosal sinus (ppt) oinferior petrosal sinus internal jugular vein Quote Walang joke si doc eh. Sad.