Skull Anatomy PDF

SKULL SKULL PLANES, POINTS & LINE  Midsagittal plane (MSP) 11.) TMJ Syndrome  Interpupillary line (IPL)  Dysfunction of the temporomandibular joint  Acanthion  Outer canthus...

SKULL SKULL PLANES, POINTS & LINE  Midsagittal plane (MSP) 11.) TMJ Syndrome  Interpupillary line (IPL)  Dysfunction of the temporomandibular joint  Acanthion  Outer canthus A.) SKULL  Infraorbital margin  External acoustic meatus (EAM) PA PROJECTION  Orbitalmeatal line (OML) PP: Prone; forehead & nose against IR; MSP & OML perpendicular to IR  Infraorbitomeatal line (IOML)/Frankpurt RP: Nasion Line CR: Perpendicular  Acanthiomeatal line (AML) SS: Petrous pyramid completely filled the orbits;  Mentomeatal line (MML) frontal bone  Between OML & IOML: 7o difference  Between OML & GML: 8o difference AP PROJECTION PP: Supine; MSP & OML perpendicular to IR PATHOLOGY RP: Nasion 1. ) Basal Fx CR: Perpendicular  Fx located at the base of the skull SS: Same as PA, but the image is MAGNIFIED 2) Blowout Fx  Fx of the floor of the orbit MODIFIED CALDWELL METHOD 3.) Contre-Coup Fx PA AXIAL PROJECTION  Fx to one side of a structure caused by PP: Prone; forehead & nose against IR; OML trauma to the other side perpendicular to IR; MSP perpendicular to IR 4.) Depressed Fx RP: Nasion  Fx causing a portion of the skull to be CR: 15o caudad depressed into the cranial cavity SS: 5.) Le Fort Fx -General Survey Examination:  Bilateral horizontal fxs of the maxillae  Anterior & side walls of the cranium 6.) Linear Fx  Temporal fossae  Irregular or jagged fx of the skull  Frontal sinuses & anterior ethmoid sinus 7.) Tripod Fx  Crista galli  Fx of the zygomatic arch & orbital floor/rim  Upper 2/3 of orbits & dislocation of the frontozygomatic suture  Petrous pyramid to lower 1/3 of orbit 8.) Mastoiditis -Superior orbital fissure/sphenoid fissure (20-25o  Inflammation of mastoid antrum & air cells caudad) & foramen rotundum (25-30o caudad) 9.) Paget’s Disease  Thick, soft bone marked by bowing fxs AP AXIAL PROJECTION 10.) Sinusitis PP: Supine; OML perpendicular to IR  Inflammation of one or more of the RP: Nasion paranasal sinuses CR: 15o cephalad 1  SKULL SS: Same as PA axial but orbits are magnified & SS: the distance b/n lateral margin of orbits & temporal -“SPDOP” bones are less on AP than PA  Symmetric petrous pyramid  Posterior portion of foramen magnum TRUE/ORIGINAL CALDWELL  Dorsum sellae & posterior clinoid process PP: Prone; forehead & nose against IR; GML w/in shadow of foramen magnum perpendicular to IR; MSP perpendicular to IR  Occipital bone RP: Nasion  Posterior portion of parietal bone CR: 23o caudad -Tomographic studies of ears, facial canal, jugular SS: Same as above foramina & rotundum foramina -Entire foramen magnum jugular foramina (40-60o LATERAL PROJECTION caudad to OML) PP: Semiprone; MSP & IOML parallel to IR; IPL -Posterior portion of cranial vault (CR ┴ to midway perpendicular to IR b/n frontal tuberosities) RP: 2 in. Above EAM or midway b/n inion & glabella TOWNE/ALTSCHUL/GRASHEY/CHAMBER CR: Perpendicular LAINE METHOD SS: AP AXIAL PROJECTION -General survey examination PP: Lateral decubitus; OML/IOML & MSP  Sella turcica perpendicular to IR  Anterior & posterior clinoid processes, RP: 2.5-3 in. above glabella  Dorsum sellae CR: 30o caudad (OML ┴); 37o caudad (IOML ┴)  Superimposed mandibular rami SS: Same as above  Mastoid region ER: For patient w/ pathologic condition, trauma or  EAM & TMJ deformity (strongly accentuated dorsal kyphosis) CROSSTABLE LATERAL HAAS METHOD PP: Dorsal decubitus (Robinson, Meares & Goree PA AXIAL PROJECTION recommendation); MSP perpendicular to IR PP: Prone; MSP & OML perpendicular to IR; RP: 2 in. Above EAM forehead & nose against the table; IR center 1 in. to CR: Horizontal nasion ER: For traumatic sphenoid sinus effusion (basal RP: 1.5 in. below inion (entrance); 1.5 in. superior skull fx) to nasion (exit) CR: 25o cephalad to OML TOWNE/ALTSCHUL/GRASHEY/CHAMBER SS: LAINE METHOD  Occipital bone AP AXIAL PROJECTION  Symmetric petrous pyramid PP: Supine; OML/IOML & MSP perpendicular to  Dorsum sellae & posterior clinoid processes IR; w/in shadow of foramen magnum RP: 2.5-3 in. above glabella ER: For obtaining image of sellar structures (DS & CR: 30o caudad (OML ┴); 37o caudad (IOML ┴) PCP) w/in FM on hypersthenic & obese patient 2  SKULL SCHULLER/PFEIFFER METHOD LYSHOLM METHOD SUBMENTOVERTICAL PROJECTION AXIOLATERAL METHOD PP: Supine or Seated-upright (more comfortable); PP: Semiprone; MSP parallel to IR; IOML parallel IOML parallel to IR; MSP perpendicular to IR; to transverse axis of IR; IPL perpendicular to IR head rested on vertex; neck hyperextended RP: 1 in. distal to lower EAM (exit) RP: ¾ in. anterior to EAM (sella turcica) CR: 30-35o caudad CR: Perpendicular to IOML; MSP of throat b/n SS: Oblique position of lateral aspect of cranial gonion (entrance) base closest to IR SS: Cranial base ER: For patients who cannot extend their head  Foramen ovale & spinosum (best enough for a satisfactory SMV projection demonstrated)  Symmetric petrosae VALDINI METHOD  Mastoid processes PA AXIAL PROJECTION  Carotid canals PP: Recumbent or seated-erect (more comfortable);  Sphenoidal & ethmoidal sinuses upper frontal region of skull against IR; MSP  Mandible perpendicular to IR; head acutely flexed; IOML 50o/OML 50o; line extending from inion to 0.5 cm  Bony nasal septum distal to nasion form 28o to CR  Dens of axis RP: 0.5 cm distal to nasion (dorsum sellae);  Occipital bone foramen magnum/slightly above level of EAM  Maxillary sinus superimposed over the (petrosae) mandible CR: Perpendicular; inion (entrance); 0.5 cm distal  Zygomatic arches (well demonstrated if to nasion (exit) exposure factors are decreased) SS:  Axial tomography of orbits, optic canals,  DILA (IOML 50o): Dorsum sellae; Internal ethmoid bone, maxillary sinuses & mastoid Auditory Meatus (IAM); LAbyrinth processes  ETB “EaT Bulaga” (OML 50o): External auditory meatus; Tymphanic cavity; Bony SCHULLER METHOD part of Eustachian tube VERTICOSUBMENTAL PROJECTION  Dorsum sellae & posterior clinod processes PP: Prone; chin fully hyperextended; MSP within or above shadow of foramen magnum perpendicular to IR  Tubeculum sellae, anterior clinoid processes RP: ¾ in. anterior to EAM (sella turcica)\ & sella turcica below shadow of foramen CR: Perpendicular to IOML; MSP of throat b/n magnum gonion (entrance)  Mastoid pneumatization SS: Same as SMV  Distorted & magnified basal structures B.) SELLA TURCICA  Useful for anterior cranial base & sphenoidal sinuses LATERAL PROJECTION o IR in contact with the throat PP: Semiprone; MSP & IOML parallel to IR; IPL o Reduces magnification & distortion perpendicular to IR 3  SKULL RP: ¾ in. anterior & ¾ in. superior to EAM SS: Dorsum sellae, tuberculum sellae, anterior & CR: Perpendicular posterior clinoid processes through frontal bone SS: Superimposed anterior & posterior clinoid above ethmoidal sinuses processes; dorsum sellae C.) OPTIC CANAL/FORAMEN TOWNE METHOD PP: Supine; OML/IOML & MSP perpendicular to RHESE METHOD IR; PARIETO-ORBITAL OBLIQUE RP: 2.5-3 in. above glabella PROJECTION CR: 30o caudad (OML ┴); 37o caudad (IOML ┴) PP: Prone; affected orbit closest to IR; zygoma, SS: Sellar region nose & chin against IR (3-pt Lower Landing); AML  Dorsum sellae, tuberculum sellae & anterior perpendicular to IR; MSP 53o angle to IR clinoid processes through occipital bone RP: Affected orbit closest to IR above shadow of foramen magnum (30o CR: Perpendicular caudad) SS: Optic canal/foramen (inferior & lateral quadrant  Dorsum sellae & posterior clinoid processes of orbital shadow) w/in shadow of foramen magnum (37o  PAZAM: Prone; Affected orbit against IR; caudad) Zynoch; AML ┴; MSP 53o to IR  Symmetric petrous pyramid RHESE METHOD HAAS METHOD ORBITO-PARIETAL OBLIQUE PA AXIAL PROJECTION PROJECTION PP: Prone; MSP & OML perpendicular to IR; PP: Supine; affected orbit away from IR; AML forehead & nose against the table; IR center 1 in. to perpendicular to IR; MSP 53o angle to IR nasion RP: Inferior and lateral margin of uppermost orbit RP: 1.5 in. below inion (entrance); 1.5 in. superior CR: Perpendicular to nasion (exit) SS: Magnified optic canal/foramen CR: 25o cephalad to OML  Increased radiation dose to lens of eye SS:  Dorsum sellae & posterior clinoid processes ALEXANDER METHOD w/in shadow of foramen magnum ORBITO-PARIETAL OBLIQUE  Symmetric petrous pyramid PROJECTION ER: For obtaining image of sellar structures (DS & PP: Erect/supine; IR 15o angle from vertical; MSP PCP) w/in FM on hypersthenic & obese patients 40o to IR; AML perpendicular to IR RP: Inferior and lateral margin of uppermost orbit PA PROJECTION CR: Perpendicular PP: Prone; forehead & nose against IR; MSP & SS: Optic canal/foramen OML perpendicular to IR RP: Glabella CR: 10o cephalad 4  SKULL MODIFIED LYSHOLM METHOD  Well demonstrated at 15o caudal angle ECCENTRIC ANGLE PARIETO-ORBITAL (Caldwell) OBLIQUE PROJECTION  Petrous portions at or below the inferior PP: Prone; forehead & nose against IR; IOML orbital margin perpendicular to IR; MSP 20o from vertical; RP: Affected orbit (exit) F.) INFERIOR ORBITAL FISSURES CR: 20o caudad or 30o caudad SS: Optic canal/foramen & anterior clinoid BERTEL METHOD processes (20o); superior orbital fissure (30o) PA AXIAL PROJECTION PP: Prone; forehead & nose against IR; IOML D.) SPHENOID STRUT perpendicular to IR -the inferior root of lesser wing of sphenoid RP: Nasion bone- CR: 20-25o cephalad SS: Inferior orbital fissures HOUGH METHOD  b/n shadows of pterygoid process of PARIETO-ORBITAL OBLIQUE sphenoid bone & mandibular ramus PROJECTION  Anterior image of each orbital floor PP: Prone; superciliary ridge/arch & side of the nose against IR; IOML perpendicular to IR; MSP G.) EYE- FOREIGN BODY LOCALIZATION 20o from vertical; MSP 20o toward the side of interest LATERAL PROJECTION RP: Affected orbit (exit) PP: Semiprone; MSP parallel to IR; IPL CR: 7o caudad perpendicular to IR; instruct patient to look straight SS: Unobstructed & undistorted image of the ahead during exposure sphenoid strut (lie b/n sphenoidal sinus & combined RP: Outer canthus shadows of anterior clinoid processes & lesser wing CR: Perpendicular of sphenoid bone) SS: Superimposed orbital roofs E.) SUPERIOR ORBITAL/SPHENOID PA AXIAL PROJECTION FISSURES PP: Prone; forehead & nose against IR; MSP & OML perpendicular to IR; instruct patient to close CALDWELL METHOD the eyes PA AXIAL PROJECTION RP: Midorbits PP: Prone; forehead & nose against IR; OML CR: 30o caudad perpendicular to IR SS: Petrous pyramids lying below orbital shadows RP: Nasion CR: 20-25o caudad or 15o caudad MODIFIED WATERS METHOD SS: Superior orbital fissures PARIETOACANTHIAL PROJECTION  Lying on the medial side of orbits b/n PP: Prone; chin against IR; MSP perpendicular to greater & lesser wings of sphenoid) IR; OML 50o to IR (new); OML 25-37o to IR (old); instruct patient to close the eyes 5  SKULL RP: Midorbits  CR perpendicular CR: Perpendicular  CR 15-25o cephalad SS: Petrous pyramids lying well below orbital shadows PFEIFFER-COMBERG METHOD  A leaded contact lens is placed directly over VOGT-BONE-FREE POSITION the cornea  Taken to detect small or low density foreign  Apparatus: particles located in the anterior segment of o Contact lens localization device the eyeball/eyelids o Pedestal type of film holder  2 Projections: lateral & superoinferior  2 Projections:  2 Movements: o Waters Method: o Vertical: 2 exposures (for lateral)  CR horizontal  Look up as far as possible o Lateral:  Look down as far as possible  CR perpendicular o Horizontal: 2 exposures (for superoinferior) H.) FACIAL BONE  Look to extreme right  Look to extreme left LATERAL PROJECTION PP: Semiprone; MSP & IOML parallel to IR; IPL PARALLAX METHOD perpendicular to IR  First described by Richards RP: Zygoma/malar bone  It determines whether the foreign body is CR: Perpendicular located within the eyeball requires no SS: Superimposed facial bones special apparatus  Superimposed mandibular rami & orbital  Not considered as precision localization roofs procedure  Widely used as preliminary check only WATERS METHOD  2 Projections: PARIETO-ACANTHIAL PROJECTION o Lateral: 2 exposures PP: Prone; MSP & MML perpendicular to IR; OML 37o to IR; nose ¾ in. (1.9 cm) away from IR o PA: 2 exposures RP: Acanthion (exit) CR: Perpendicular SWEET METHOD SS: Orbits, maxillae & zygomatic arches  It determines the exact location of a foreign  Best projection for facial bones body by use of a geometric calculations  Petrous ridges below the maxillae  Apparatus:  Blow out fractures o Sweet localizing device o Sweet film pedestal MODIFIED WATERS  1 Projection: PP: Prone; MSP & MML perpendicular to IR; o Lateral: 2 exposures OML 55o to IR RP: Acanthion (exit) 6  SKULL CR: Perpendicular  Zygomatic bone SS: Facial bones w/ less axial angulation  Anterior wall of maxillary sinus of side up  Petrous ridges below the inferior border of orbits I.) NASAL BONE REVERSE WATERS METHOD LATERAL PROJECTION AP AXIAL PROJECTION PP: Semiprone; MSP & IOML parallel to IR; IPL PP: Supine; MSP & MML perpendicular to IR; perpendicular to IR OML 37o to IR; chin up RP: ¾ in. (old) or ½ in. (new) distal to nasion RP: Acanthion (exit) CR: Perpendicular CR: Perpendicular SS: Nasal bones of side down & soft tissue SS: Superior facial bones; same as True/Original structures Waters, but the image is MAGNIFIED ER: For patient who cannot be placed in the prone TANGENTIAL PROJECTION position PP:  Extraoral Film (Cassette): prone; chin rested CALDWELL METHOD on sandbags; chin fully extended; MSP & PA AXIAL PROJECTION GAL perpendicular to IR PP: Prone; forehead & nose against IR; OML  Intraoral Film (Occlusal Film): supine; head perpendicular to IR elevated; MSP perpendicular to sponge; RP: Nasion GAL parallel to sponge & perpendicular to CR: 15o caudad or 30o caudad (Exaggerated film Caldwell) RP: Glabelloalveolar line SS: Orbital rims, maxillae, nasal septum, zygomatic CR: Perpendicular bones & anterior nasal spine SS: Nasal bones with minimal superimposition  Petrous ridges at lower third of orbits (15o ER: For demonstration of any medial or lateral caudad) displacement of fragments in fractures  Petrous ridges below the inferior orbital Contraindications: margins (30o caudad)  Children or adults who have very short nasal  Orbital floors (30o caudad) bones, concave face or protruding upper teeth LAW METHOD PA OBLIQUE AXIAL PROJECTION WATERS METHOD PP: Semiprone; zygoma, nose & chin against IR; PARIETO-ACANTHIAL PROJECTION unaffected side against IR; OML perpendicular to PP: Prone; MSP & MML perpendicular to IR; IR; Center IR 2 in. above floor of maxillary sinuses OML 37o to IR; nose ¾ in. (1.9 cm) away from IR RP: Lower antrum RP: Acanthion (exit) CR: 25-30o cephalad; posterior to gonion (entrance) CR: Perpendicular SS: Floor & posterior wall of maxillary sinus ER: Displacement of bony nasal septum & (antrum) of side down depressed fx of nasal wings  External orbital wall 7  SKULL J.) ZYGOMATIC ARCHES SS: Bilateral symmetric zygomatic arches free of superimposition SCHULLER/PFEIFFER METHOD SUBMENTOVERTICAL PROJECTION K.) MANDIBLE PP: Supine or Seated-upright (more comfortable); IOML parallel to IR; MSP perpendicular to IR; PA PROJECTION head rested on vertex; neck hyperextended PP: Prone; forehead & nose against IR; OML & RP: 1 in. posterior to outer canthi MSP perpendicular to IR CR: Perpendicular to IOML; MSP of throat b/n RP: Acanthion (exit) gonion (entrance) CR: Perpendicular SS: Best demonstrates bilateral symmetric SS: Mandibular rami zygomatic arches ER: To demonstrate any medial or lateral displacement of fragments in fractures of the rami MODIFIED TITTERINGTON METHOD PA AXIAL (SUPEROINFIOR) PROJECTION PA AXIAL PROJECTION PP: Prone; nose & chin against IR; MSP PP: Prone; forehead & nose against IR; OML & perpendicular to IR MSP perpendicular to IR RP: Vertex midway b/n zygomatic arches RP: Acanthion (exit) CR: 23-38o caudad CR: 20 or 25o cephalad SS: Well shown zygomatic arches SS: Condylar processes; mandibular rami ER: To demonstrate any medial or lateral MAY METHOD displacement of fragments in fractures of the rami TANGENTIAL PROJECTION PP: Prone/seated; neck fully extended; IOML PA PROJECTION parallel to IR; MSP rotated 15o toward the side of PP: Prone; nose & chin against IR; AML & MSP interest; head tilted 15o perpendicular to IR RP: Zygomatic arch at 1.5 in. posterior to outer RP: Level of lips canthus CR: Perpendicular CR: Perpendicular to IOML SS: Mandibular body SS: Zygomatic arch free of superimposition ER: Useful with patients who have depressed PA AXIAL PROJECTION fractures or flat cheekbones PP: Prone; nose & chin against IR; AML & MSP perpendicular to IR; fill the mouth with air to MODIFIED TOWNE METHOD obtained better contrast around TMJs (Zanelli AP AXIAL PROJECTION recommendation) JUG HANDLE VIEW RP: Midway b/n TMJs PP: Supine; OML/IOML & MSP perpendicular to CR: 30o cephalad IR; SS: Mandibular body; TMJs; condylar processes RP: Glabella (1 in. above nasion) CR: 30o caudad (OML ┴); 37o caudad (IOML ┴) 8  SKULL AXIOLATERAL OBLIQUE PROJECTION PANORAMIC TOMOGRAHY/ PP: Seated/semiprone/semisupine; head in true PANTOMOGRAPHY/ROTATIONAL lateral & IPL perpendicular to IR (ramus); head TOMOGRAPHY rotated 30o toward IR (body); head rotated 45o -technique employed to produced tomograms of toward IR (symphysis); head rotated 10-15o toward curved surfaces- IR (general survey); mouth closed; neck extended  Provides panoramic image of the entire (prevent superimposition of cervical spine) mandible, TMJ, dental arches RP: Mandibular region of interest  Provides distortion-free lateral image of the CR: 25o cephalad entire mandible SS: Mandibular body & TMJs  Patients who sustained severe mandibular or ER: To place the desired portion of the mandible TMJ trauma parallel with the IR  Useful for general survey studies of dental Muscular/Hypersthenic Patients: MSP 15o & CR abnormalities 10o cephalad  Adjuvant for pre-bone marrow transplant  To reduce the possibility of projecting shoulder over the mandible L.) TEMPOROMANDIBULAR JOINTS SCHULLER/PFEIFFER METHOD TOWNE METHOD SUBMENTOVERTICAL PROJECTION AP AXIAL PROJECTION PP: Supine or Seated-upright (more comfortable); PP: Supine; MSP & OML perpendicular to IR IOML parallel to IR; MSP perpendicular to IR;  Closed-mouth Position: posterior teeth in head rested on vertex; neck hyperextended contact not incisors RP: Midway b/n gonions o Rationale: prevents mandibular CR: Perpendicular to IOML protrusion & condyles to be carried SS: Mandibular body; coronoid & condyloid out of mandibular fossae processes of rami  Opened-mouth Position: open as wide as possible SCHULLER METHOD o Mandible not protruded (jutted VERTICOSUBMENTAL PROJECTION forward) PP: Prone; chin fully hyperextended; IR against o Not perform in trauma patients throat; MSP perpendicular to IR RP: 3 in. above nasion RP: Level just posterior to outer canthi CR: 35o caudad CR: Perpendicular to IOML or occlusal plane SS: Mandibular condyles & mandibular fossae of SS: Condyle & neck of condylar processes are temporal bones better shown (CR ┴ occlusal plane)  Closed-mouth: condyle lying in mandibular fossa  Opened-mouth: condyles lying inferior to articular tubercle 9  SKULL AXIOLATERAL PROJECTION SS: TMJ PP: Semiprone; head in lateral position; IPL perpendicular to IR; MSP parallel to IR; closed- ZANELLI METHOD mouth & opened-mouth position LATERAL TRANSFACIAL POSITION RP: 0.5 in. anterior & 2 in. superior to upside EAM PP: Lateral recumbent; head in true lateral; head CR: 25-30o caudad resting on parietal region; MSP 30o to IR SS: TMJ anterior to EAM RP: Uppermost gonion (entrance)  Closed-mouth: condyle lying in mandibular CR: Perpendicular fossa SS: TMJ  Opened-mouth: condyles lying inferior to articular tubercle M.) SINUSES Cross & Flecker: pointed out the value of erect SCHULLER METHOD position AXIOLATERAL OBLIQUE/LATERAL  To demonstrate presence or absence of fluid TRANSCRANIAL/AXIAL TRANSCRANIAL  To differentiate between shadows caused by PROJECTION fluid & those caused by pathology PP: Semiprone; MSP rotated 15o toward the IR; AML parallel to transverse axis of IR; LATERAL PROJECTION RP: 1.5 in. superior to upside EAM PP: Upright RAO/LAO or dorsal decubitus (can’t CR: 15o caudad; TMJ of sidedown (exit) assume upright); head in true lateral; MSP parallel SS: Condyles & neck of the mandible to IR; IPL perpendicular to IR; IOML parallel to  Closed-mouth: fracture of the neck & transverse axis of IR; condyle of ramus RP: 0.5-1 in. posterior to outer canthus  Opened-mouth: mandibular fossa; inferior & CR: Perpendicular anterior excursion of the condyle SS: All paranasal sinuses INFEROSUPERIOR TRANSFACIAL PA PROJECTION POSITION PP: Upright; forehead & nose against IR; MSP & PP: Semiprone; head in true lateral; IPL 10-15o OML perpendicular to IR from perpendicular; MSP 15o from IR RP: Nasion (┴); glabella (10o cephalad); midregion RP: Uppermost gonion of maxillary sinuses (┴) CR: 30o cephalad CR: Perpendicular; 10o cephalad; perpendicular SS: TMJ SS:  Posterior ethmoid sinuses inferior to cranial ALBERS-SCHONBERG METHOD bones & superior to anterior ethmoid sinuses LATERAL TRANSFACIAL POSITION (┴) PP: Semiprone; head in true lateral; IPL  Sphenoidal sinuses through frontal bone & perpendicular to IR; MSP parallel to IR; IOML superior to frontal & ethmoid sinuses parallel to transverse axis of IR  Maxillary sinuses inferior to cranial base RP: TMJ closes to IR (exit) CR: 20o cephalad 10  SKULL CALDWELL METHOD SCHULLER METHOD PA AXIAL PROJECTION SUBMENTOVERTICAL PROJECTION PP: Upright PP: Upright; IOML parallel to IR; MSP  Angle grid technique: nose & forehead perpendicular to IR; head rested on vertex; neck against IR; IR tilted 15o; MSP & OML hyperextended perpendicular to IR RP: ¾ in. anterior to EAM (sella turcica)  Vertical grip technique: nose against IR; CR: Perpendicular to IOML; MSP of throat b/n OML 15o from IR; sponge b/n forehead & gonion (entrance) IR; MSP perpendicular to IR SS: Sphenoidal & ethmoidal sinuses RP: Nasion  Anterior portion of the base of the skull CR: Horizontal SS: Frontal sinuses & anterior ethmoidal sinuses SCHULLER METHOD VERTICOSUBMENTAL PROJECTION WATERS METHOD PP: Seated-erect; chin fully hyperextended; MSP PARIETOACANTHIAL PROJECTION perpendicular to IR PP: Upright; neck hyperextended & rested against RP: ¾ in. anterior to EAM (sella turcica) IR; OML 37o to IR; MML perpendicular to IR CR: Perpendicular to IOML; MSP of throat b/n RP: Acanthion gonion (entrance) CR: Horizontal SS: Sphenoidal sinuses SS: Maxillary sinuses  Posterior ethmoidal sinuses  Petrous pyramids inferior to floor of  Maxillary sinuses maxillary sinus  Nasal fossae  Foramen rotundum  Distorted frontal & ethmoidal sinuses PIRIE METHOD AXIAL TRANSORAL POSITION OPEN-MOUTH WATERS METHOD PP: Upright (prone; nose & chin against IR; mouth PARIETOACANTHIAL PROJECTION wide open; MSP perpendicular to IR; phonate “ah” PP: Upright; neck hyperextended & rested against during exposure IR; OML 37o to IR; MML perpendicular to IR; RP: ¾ in. anterior to EAM (sella turcica) mouth wide open CR: Perpendicular RP: Acanthion SS: Sphenoidal sinuses projected through open CR: Horizontal mouth SS: Sphenoidal sinuses projected through open  Maxillary sinuses mouth  Nasal fossae  Petrous pyramids inferior to floor of maxillary sinus RHESE METHOD ER: For the patients who cannot be placed in PA OBLIQUE POSITION position for SMV PP: Seated-erect; zygoma, nose & chin against IR; AML perpendicular to IR; MSP 53o from IR RP: Upper parietal region CR: Perpendicular 11  SKULL SS: Oblique image of posterior & anterior  Sigmoid sinus ethmoidal sinuses  Lateral portion of pars petrosa  Frontal & sphenoidal sinuses  Tegmen tymphani  Profile image of the optic canal  Superimposed internal & external auditory meatuses LAW METHOD  Mastoid emissary vessel (when present) PA OBLIQUE POSITION PP: Seated-erect; zygoma, nose & chin against IR; MODIFIED HICKEY METHOD neck fully extended AP TANGENTIAL POSITION RP: Uppermost gonion PP: Supine; tape auricles forward; face rotated CR: 25-30o cephalad away from side of interest; MSP 55o from IR or 35o SS: Relationship of teeth to maxillary sinuses from vertical; IOML perpendicular to IR; IR caudally inclined 15o N.) MASTOID RP: 1 in. superior to tip of mastoid process CR: 15o caudad LAW METHOD SS: Mastoid process free of superimposition AXIOLATERAL POSITION  Projected below the shadow of occipital Double Angulation Method bone PP: Prone; head in true lateral; tape auricle forward; MSP & IOML parallel to IR; IPL perpendicular to PA TANGENTIAL POSITION IR PP: Prone; IR cranially inclined 15o; tape auricles RP: 2 in. posterior & 2 in. superior to uppermost forward; cheek against IR; face rotated away from EAM side of interest; MSP 55o from IR or 35o from CR: 15o caudad & 15o anterior vertical; IOML perpendicular to IR Lange Recommendations: RP: 1 in. superior to tip of mastoid process  25o caudad & 20o anterior CR: 15o cephalad  Auricles taped forward SS: Mastoid process free of superimposition Single Angulation Method  Projected below the shadow of occipital PP: Prone; tape auricle forward; MSP rotated 15o bone toward IR RP: 2 in. posterior & 2 in. superior to uppermost TOWNE METHOD EAM AP AXIAL PROJECTION CR: 15o caudad PP: Supine; OML/IOML & MSP perpendicular to Part Angulation Method IR; PP: Prone; head rested on flat surface of cheek; RP: 2 in. above glabella or 2.5 in. above nasion tape auricle forward; MSP rotated 15o towards IR; CR: 30o caudad (OML ┴); 37o caudad (IOML ┴) IPL 15o from vertical SS: RP: 2 in. posterior & 2 in. superior to uppermost  Internal auditory canals EAM  Petrous portion of temporal bone CR: ┴  Labyrinths SS: Mastoid cells 12  SKULL  Mastoid antrum  Labyrinths  Middle ears  Mastoid antrum  Dorsum sellae w/in foramen magnum  Middle ears  Dorsum sellae w/in shadow of foramen HENSCHEN, SCHULLER, & LYSHOLM magnum METHODS AXIOLATERAL POSITIONS HAAS METHOD PP: Semiprone; head in true lateral; MSP parallel to PA AXIAL PROJECTION IR; IPL perpendicular to IR; IOML parallel to PP: Prone; MSP & OML perpendicular to IR; transverse axis of IR; auricles taped forward forehead & nose against the table; IR center 1 in. to RP: Dependent EAM closest to IR nasion CR: 15o caudad (Henschen/Cushing); 25o caudad RP: Nasion (Schuller); 35o caudad (Lysholm/Runstrom II) CR: 25o cephalad SS: Mastoid & petrous portion SS: Symmetric axial frontal image of petrous  Mastoid cells, mastoid antrum, IAM & portions projected above the base of the skull EAM & tegmen tympani (Henschen)  IAM  Tumors of the acoustic nerve (Cushing)  Labyrinths  Pneumatic structures of mastoid process,  Mastoid antrums mastoid antrum, tegmen tympani, IAM &  Middle ears EAM, sinus & dural plates & mastoid  Dorsum sellae & posterior clinoid processes emissary when present (Schuller) w/in shadow of foramen magnum  Mastoid cells, matoid antrum, IAM & EAM, ER: For patients who cannot assume AP axial tegmen tympani, labyrinthine area & carotid position canal (Lysholm/Runstrom II) Runstrom Recommendation: VALDINI METHOD  Exposure made with open mouth PA AXIAL PROJECTION  For visualization of petrous apex between PP: Recumbent or seated-erect (more comfortable); anterior wall of EAM & mandibular condyle upper frontal region of skull against IR; MSP perpendicular to IR; head acutely flexed; IOML O.) PETROUS PORTION 50o/OML 50o; line extending from inion to 0.5 cm distal to nasion form 28o to CR TOWNE METHOD RP: 0.5 cm distal to nasion (dorsum sellae); AP AXIAL PROJECTION foramen magnum at or slightly above level of EAM PP: Supine; OML/IOML & MSP perpendicular to (petrosae) IR; CR: Perpendicular; inion (entrance); 0.5 cm distal RP: MSP b/n EAMs to nasion (exit) CR: 30o caudad (OML ┴); 37o caudad (IOML ┴) SS: SS: Petrosae above base of the skull  DILA (IOML 50o): Dorsum sellae; Internal  IAM Auditory Meatus (IAM); LAbyrinth  Arcuate eminences 13  SKULL  ETB “EaT Bulaga” (OML 50o): External  Mastoid antrum auditory meatus; Tymphanic cavity; Bony Owen Modifications: cited by Pendergrass, part of Eustachian tube Schaeffer & Hodes  PP: MSP 40o to IR; IR & head angled 10o SCHULLER/PFEIFFER METHOD caudally SUBMENTOVERTICAL (SUBBASAL)  CR: 28o caudally PROJECTION Owen Modifications: described by Etter & Cross PP: Supine or Seated-upright (more comfortable);  PP: MSP 30o to IR OML parallel to IR or CR perpendicular to OML  CR: 25-30o caudally Owen Modifications: described by Compere (cannot fully extend the neck) or supraorbitomeatal  PP: MSP 30-45o to IR line (SOML) parallel to IR; MSP perpendicular to IR; head rested on vertex; neck hyperextended  CR: 30o caudally RP: ¾ in. anterior to EAM (sella turcica) Owen Modifications: used by Zizmor CR: Perpendicular to OML at midway b/n EAMs or  PP: MSP 15o to IR 15-20o anteriorly at MSP of throat 1 in. anterior to  CR: 35o caudally EAMs SS: Symmetric petrosae STENVERS METHOD  Mastoid processes POSTERIOR PROFILE POSITION  Labyrinths PP: Prone; forehead, nose & zygoma against IR (3-  EAMs pt Upper Landing); IOML parallel to transverse axis  Tympanic cavities of IR; face rotated away from side of interest; MSP  Acoustic/auditory ossicles 45o to IR Hirtz Method: RP: 1 in. anterior to EAM closest to IR (exit)  RP: Midway b/n & 1 in. anterior to EAMs CR: 12o cephalad  CR: 5o anteriorly SS: Pars petrosa closest to IR  Petrous ridge MAYER METHOD  Cellular structure of mastoid process AXIOLATERAL OBLIQUE PROJECTION  Mastoid antrum PP: Supine; auricles taped forward; outer side of IR  Area of tympanic cavity elevated (reduces part-film distance); MSP 45o from  Labyrinth IR; chin depressed; IOML parallel to IR  IAM RP: Dependent EAM  Cellular structure of petrous apex CR: 45o caudad SS: Axial oblique of petrosa ARCELIN METHOD  Petrosa inferior to mastoid air cells ANTERIOR PROFILE POSITION  EAM REVERSE STENVERS METHOD  Tympanic cavity & ossicles PP: Supine; IOML perpendicular to IR; face rotated  Epitympanic recess (attic) away from side of interest; MSP 45o to IR  Aditus 14  SKULL RP: 1 in. anterior & ¾ in. superior to EAM closest to IR (exit) CR: 10o caudad SS: Magnified pars petrosa away from IR ER: Useful with children & with adults who cannot be position for Stenvers Method MODIFIED LAW METHOD AXIOLATERAL POSITION Single Angulation Method PP: Prone; taped auricle forward; Head rotated 15o toward IR; MSP 15o RP: 2 in. posterior & 2 in. superior to uppermost EAM CR: 15o caudad SS:  Mastoid cells  Lateral portion of pars petrosa  Superimposed IAM & EAM  Mastoid emissary vessel (when present)  THE END  “BOARD EXAM is a matter of PREPARATION. If you FAIL to prepare, you PREPARE to fail” 04/01/14 15