1 1 Radiographic Technique 2 RAD 1204 A. Tahani Ahmed AL-Hozeam

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Radiographic Technique 2RAD 1204

A . Tahani Ahmed AL-Hozeam

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TECHNICAL ASPECTS

Sitting erect positions are preferred to exclude any air-fluid levels within the cranial cavities or sinuses.

Patient comfort and skull immobilization are necessary.

Exposure factors range between 75 kVp and 85 kVp. A small focus is to be used with short times and

high mA.

A high lattice grid (40 lines/inch) must be used, FFD=100cm.

Good collimation (Narrow cone for small parts) and non-repeats helps

in minimizing the radiation exposure to the patient.

A contact shield should be used over the neck and chest to reduce the exposure to the thyroid and

female breast in the AP projection.

SKULL AND CRANIAL BONES

AP Axial (Towne’s projection) B

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For occipital bone, skull #s, neoplastic processes, and Paget’s disease. , foramen magnum .

Film: HD 24x30 cm longthwise .

Remove all metal , plastic ,or other removable objects from patient’s head. Patient supine, or in erect AP sitting, chin is depressed (OML 90 to film), patients unable to flex neck to IOML perpendicular to the film, support under head ,no rotation of the head .

CP: 2.5 inches ( 6 cm ) above the glabella .

CR: 30 caudal to OML , OR 37 caudal to IOML .

Lateral Skull (general) B

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For skull #s, neoplastic processes, and Paget’s disease. Same indication A horizontal beam is used for trauma cases to show air-fluid levels in the sphenoid sinus (a sign of # in the base of skull with internal bleeding) .Film: HD 24x30 cm crosswise .

Remove all metal , plastic ,or other removable objects from patient’s head .Patient in a semiprone , recumbent or erect sitting, head in a true lateral (required side close to the film), MSP parallel to film, IPL 90 to film.

CP: 5 cm superior to EAM .CR: 90 to film center .

NB/ patients in recumbent put support placed under the chin to help in maintaining a true lateral position.

PA Skull (0 Occipital-frontal) projection

B

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For frontal bone,skull #s and neoplastic processes , Paget’s disease.

Film: HD 24x30 cm longthwise .

Remove all metal , plastic ,or other removable objects from patient’s head . Patient in the erect or prone position. rest patient’s nose and forehead against the couch center, neck flexed so that OML is 90 to the film, MSP 90 to film, head not rotated.

CP: Exits the glabella

CR: 90 to film center

NB/ AP is not recommended as it produces 200 times eyes absorbed dose produced in the PA position.

PA Axial Skull (15 Caldwell) projection B

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For skull #s, neoplastic processes , paget’s disease .

Film: HD 24x30 cm longthwise .

Remove all metal , plastic ,or other removable objects from patient’s head . Patient in the erect or prone position. rest patient’s nose and forehead against the couch center, neck flexed so that OML is 90 to the film, MSP 90 to film, head not rotated.

CP: Exits the naison.CR: 15 caudal .NB/ CR: 25 - 30caudal gives better view of superior orbital fissure (black arrows) and foramen rotundum and inferior region (white arrows).

Submentovertex (SMV) Skull S

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For inner temporal bone structures, basal skull #s , occipital bone, mandible, foramen ovale and foramen magnum, , sphenoidal and ethmoid sinuses and mastoid processes.

Film: HD 24x30 cm lengthwise .

Remove all metal , plastic ,or other removable objects from patient’s head . Patient supine or erect sitting, chin raised, neck hyperextended till IOML is parallel to film, MSP 90 to couch top. A pillow under patient’s back allows for sufficient extension.CP: Midway between angles of mandible (2 cm anterior to level of EAMs).

CR: 90 to IOML.

PA Axial Skull (Haas projection ) S

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It shows occipital bone, petrous pyramids, the foramen magnum .An alternate projection for the Towne’s view if the patient cannot flex his neck sufficiently for the reverse (counter) Towne projection. NB/ It is not recommended, however, for the occipital bone because of the magnification it produces. Film: HD 24x30 cm lengthwise. Remove all metal , plastic ,or other removable objects from patient’s head . Patient in the erect or prone position. rest patient’s nose and forehead against the couch center, neck flexed so that OML is 90 to the film, MSP 90 to film, head not rotated.CP: Through level of EAMsCR: 25 cephalic to OML.

AP Axial (Towne’s projection – for AP Sella Turcica) B

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Detects pituitary adenomas in the sella turcica.

Also shows dorsum sellae, posterior clinoids, the foramen magnum.

Film: HD 18x24 cm lengthwise.

Remove all metal , plastic ,or other removable objects from patient’s head. Patient supine, or in erect AP sitting, patients flex neck to IOML perpendicular to the film, MSP 90 to the film .

CP: 4 cm above superciliary arch

CR: 37 caudal (for the dorsum sellae and the posterior clinoids), 30 caudal (for anterior clinoids)

Lateral Skull (for lateral Sella Turcica) B

To show pituitary adenomas.

Film: HD 18x24 cm crosswise .

Remove all metal , plastic ,or other removable objects from patient’s head. Patient in an erect or semiprone .true lateral position, IPL is 90 to the film , MSP is parallel to the film , IOML is 90 to the film .

CP: 2 cm anterior and 2 cm superior to EAM.CR: 90 to film center

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Facial Bones

PA Axial Skull (15 Caldwell) projection for Facial bones B

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For skull #s, neoplastic / inflammatory processes of the facial bones .

Film: HD 24x30 cm longthwise .

Remove all metal , plastic ,or other removable objects from patient’s head . Patient in the erect or prone position. rest patient’s nose and forehead against the couch center, neck flexed so that OML is 90 to the film, MSP 90 to film, head not rotated.

CP: Exits the naison.CR: 15 caudal .

Lateral Skull for facial bones B

For fractures, neoplastic or inflammatory processes of facial bones.

Film: HD 18x24 cm lengthwise.

Remove all metal , plastic ,or other removable objects from patient’s head . Patient in the erect or semi prone position. Head in true lateral (same position as for lateral skull ), chin adjusted so that both IPL and IOML are 90 to film , MSP is parallel to film.

CP: Zygoma (midway between the outer canthus and EAM)CR: 90 to film centerNB/ the facial bone routine commonly includes only a single lateral , whereas the skull routine may include bilateral positions.

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Lateral Skull (for nasal bones) B

For nasal bone fractures both sides for comparison.

Film: HD 18x24 cm detail screen.

Remove all metal , plastic ,or other removable objects from patient’s head . Patient in the erect or semi prone position. Head in true lateral , chin adjusted so that both IPL and IOML are 90 to film, MSP is parallel to the film. CP: 1.25 cm inferior to naisonCR: 90 to film centerNB/ A long narrow cone should be used.

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Superoinferior Tangential (Axial) (nasal

bones) S

For fractures of the nasal bones.

Film: HD 18x24 cm crosswise detail screen.

Place lead shield over lap or pelvic region to shield gonads. Patient prone or in the erect sitting end of the chair , chin extended and rested on cassette, angle support under film, glabelloalvolar line (GAL) 90 to cassette, long narrow cone used

CP: Naison .CR: parallel to GAL.

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Oblique inferosuperior Tangential (for zygomatic arches) B

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For #s, neoplastic, or inflammatory processes of the zygomatic arch. Both sides are generally taken for comparison.

Film: HD 18x24 longthwise.

Remove all metal , plastic ,or other removable objects from patient’s head . Patient position is erect or supine. Raise chin, hyperextending neck ,IOML is paralle to the film. Rest head on vertex of skull. head rotated 15 toward side of interest.

CP: Zygomatic arch of interest.

CR: 90 to IOML and film.

Parieto-orbital (Rhese View) for optic foramina B

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For bony abnormalities of the optic foramen. Both sides must be done for comparison.

Film: HD 18x24 cm

Remove all metal , plastic ,or other removable objects from patient’s head. Patient semi prone or erect, chin, cheek, and nose against couch, head needed angle makes 53 with the couch top, the acanthiomeatal line AML makes 90 to the film, a long narrow cone should be used. CP: Downside orbit (7 cm above and 7 cm behind the up EAM).

CR: 90 to IOML

PA (or PA Axial) Skull (for mandible ) B

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Best for the body of mandible for #s, inflammatory and neoplastic processes. PA axial well shows rami and elongated view of condyloid process.

Film: HD 18x24 cm longthwise.

Remove all metal , plastic ,or other removable objects from patient’s head. Patient prone or erect . Rast patient’s forhead and nose aginst table, chin tucked so that OML is 90 to film, MSP 90 to the couch top, head not rotated.

PA ــــCP: exit at junction of the lips

CR: 90 to film center

PA axial ــــــ CP: exit at the acanthion

CR: 20- 25 cephalic

PA PA axial

AP Axial (Towne’s projection – for mandible) B

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For #s, neoplastic or inflammatory processes of the condyloid processes of the mandible.

Film: HD 18x24 cm longthwise.

Remove all metal , plastic ,or other removable objects from patient’s head. Patient supine, or in erect , rest patient’s posterior skull in table , tuck chin, patients unable to flex neck to IOML perpendicular to the film, support under head ,no rotation of the head .

CP: Glabella

CR: 35- 40 caudal .

NB/ if patient is unable to bring OML perpendicular to image ,IOML perpendicular and increase the CR angle 7 ْ.

Lateral 25 - 30 (Axiolateral) (for mandible) B

For #s, neoplastic, or for inflammatory processes of the mandible (both sides are done for comparison) . Film: HD 18x24 cm crosswise

Head in true lateral with MSP parallel to the film, side of interest placed against the film, mouth closed, extend neck ,head then rotated in oblique true lateral best (for ramus) 30 best (for the body), 45 best (for mentum), and 10 - 15 best for a (general survey).

CP: exit Mandibular region of interest (body, ramus, ….).CR: 25 cephalic.

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Submentovertex (SMV) (for mandible) S

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For #s, neoplastic, or inflammatory processes of the mandible.

Film: HD 18x24 cm longthwise.

Remove all metal , plastic ,or other removable objects from patient’s head. Patient supine or erect sitting, chin raised, neck hyperextended till IOML is parallel to film, MSP 90 to couch top. Rest head on vertex of skull. A pillow under patient’s back allows for sufficient extension.

CP: Midway between angles of mandible

CR: 90 to IOML.

ORTHOPANTOMOGRAPHY (tomography of the mandible) S

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For #s of the mandible and TM joint pathology.

Film: HD 23x30 cm, or curved non-grid cassette

Tube and film attached at starting position, chin rest raised to same level as patient’s chin, chin rested on a sterile bite block, patient as close as possible to the tube stand, chin adjusted until IOML is parallel with the floor, occlusal plane declines 10 from posterior to anterior, patient’s lips placed together, tongue on roof of the mouth.

CP: Fixed CR and FFD. For TMJ, another film must be done with open mouth.

Lateral 15 (Modified Law for TMJs) S

For abnormal range of motion between condyle and TM fossa. Film: HD 18x24 cm longthwise.

Patient prone or erect, head in lateral, IPL 90 to film, IOML 90 ْ to the film ,then rotated face15 toward the film.CP: 4 cm superior to upside EAMCR: 15 caudal to pass through the downside TMJ.NB / one position with open mouth and other with close mouth.

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Paranasal Sinuses, Mastoids, and Temporal Bone.

PA Skull (Caldwell projection for

sinuses ) B

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Good for sinuses (frontal and anterior ethmoidal sinuses). Also shows other inflammatory conditions (sinusitis, sinus polyps).

Film: HD 18x24 cm lengthwise.

Remove all metal , plastic ,or other removable objects from patient’s head. Position patient erect .Patient’s nose and forehead against film, neck extended so that OML is 15 from the horizontal . Support between forehead and upright bucky .MSP perpendicular to film. No rotation.

CP: exit at nasion.CR: 90 horizontal to film .NB/ why we prefere the erect position?

To image the air-fluid level in sinuses.

Lateral Skull (for sinuses)

B

For inflammatory conditions( sinusitis, and sinus polyps). (good for sphenoid, frontal, ethmoid, and maxillary sinuses).

Film: HD 18x24 cm lengthwise.

Remove all metal , plastic ,or other removable objects from patient’s head. Position patient erect , head in true lateral (IPL 90 to film) , IOML perpendicular to the film.

CP: Midway between outer canthus and EAMCR: 90 horizontal to film center

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Parietoacanthial (OM) (Waters View for

sinuses ) B

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Best for maxillary and frontal sinuses and nasal fossae. Also shows other

inflammatory conditions ,sinusitis and sinus polyps.

Film: HD 18x24 cm lengthwise.

Remove all metal , plastic ,or other removable objects from patient’s

head. Position patient erect , neck extended, chin and nose against

couch, head adjusted till MML (mentomeatal line) is 90 to the film, OML

makes 37 with film, a long narrow cone should be used.mouth is closed.

CP: exit at the acanthion.

CR: 90 horizontal to film center

Parietoacanthial (OM) (Open-Mouth Waters

for sinuses ) S

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Best for maxillary and frontal sinuses and nasal fossae. Also

shows other inflammatory conditions ,sinusitis and sinus polyps.

Film: HD 18x24 cm lengthwise.

Remove all metal , plastic ,or other removable objects from patient’s head. Position patient erect , neck extended, chin and nose against couch, head adjusted till MML (mentomeatal line) is 90 to the film, OML makes 37 with film but with open mouth (patient drops his jaw without moving the head). MSP is prependicular to the film.

CP: exit at the acanthion.

CR: 90 horizontal to film center

Submentovertex (SMV) (for sinuses) S

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Best for sphenoid ,ethmoid and maxillary sinuses. Also shows other inflammatory conditions ,sinusitis and sinus polyps.

Film: HD 18x24 cm lengthwise.

Remove all metal , plastic ,or other removable objects from patient’s head. Position patient erect .chin raised, neck hyperextended till IOML is parallel to film, MSP 90 to couch top.

CP: Midway between angles of mandible (4 cm inferior to

mandibular symphysis).

CR: 90 to IOML.

NB/ 1-if patient is unable to sufficientiy extend neck ,angle the tube from horizontal as needed to align the CR perpendicular to IOML.

2- This position is very uncomfortable for patient ,have all factors set before positioning the patient and complete the projection as quickly as possible.

Axiolateral Oblique (Modified Law for mastoids) B

For bony pathology of mastoids processes. Both sides are generally exmined for comparion. Film: HD 18x24 cm lengthwise.

Remove all metal , plastic ,or other removable objects from patient’s head. Patient semi prone or erect, each auricle taped forward, head in lateral, then rotated 15 oblique toward the film, IPL 90 to couch, side of interest down.

CP: Exit downside mastoid tip (2.5 cm posterior, 2.5 cm superior to upside EAM).

CR: 15 caudal

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Axioanterior Oblique (Stenvers for mastoids) B

For advanced pathology of temporal bone. Both sides are to be examined for comparison.

Film: HD 18x24 cm lengthwise.

Remove all metal , plastic ,or other removable objects from patient’s head. Patient semiprone or erect, IOML 90 to film, chin adjusted so that head is rotated 45 oblique with the couch, side of interest down, downside mastoid region centered to film.

CP: 7 – 10 cm posterior, and 1.25 cm inferior to upside EAM to exit through downside mastoid process.

CR: 12 cephalic.

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