For the waters method for the facial bones, the orbitomeatal line is placed at what angle to the ir?

The Caldwell view is a caudally angled radiograph, with its posteroanterior projection allowing for minimal radiation to the orbits. This view may be used in imaging of the skull or facial bones depending on the clinical indications.

This view aids in visualizing the paranasal sinuses, especially the frontal sinus. It can help to assess 4 inflammatory conditions such as sinusitis and secondary osteomyelitis, and sinus polyps or cysts. Additionally, any fractures to the orbit may also be determined through this view.

the patient is seated in front of the upright detector
the patient's forehead is placed against the image detector
forehead and nose are both touching the detector
the orbitomeatal line (OML) is running perpendicular to the detector
petrous ridge is below orbits

posteroanterior (PA) projection
centering point
- angled caudad around 15° to exit at the nasion
collimation
- lateral to the skin margins
- superior and inferior to the borders of the sinus cavities
orientation
detector size
exposure
SID
grid

ADVERTISEMENT: Supporters see fewer/no ads

no rotation evident via the symmetrical nature of the orbits
the innominate lines should be equidistant from the lateral borders of the orbits
petrous ridges are projected in the lower third of the orbits
no tilting should be evident; an imaginary line through the petrous ridges should be horizontal

always guarantee that the patient is not 'hunched' over when they are being examined. This can cause an artifact from the shoulders and the patient is more likely to be rotated; it is best to move the chair up close to the detector so they are sitting up straight for the image
remember, having one's head against an upright detector is uncomfortable, so try to have everything set up before you position the patient, to ensure patient comfort
constantly use a side marker and regularly place it PA. Skulls can get tricky with figuring out which side is which. Many vendors tend to 'flip' images to make them appear AP

History and etymology

The view was first described by Eugene Wilson Caldwell in 1907 3, an American radiologist.

1. Yanagisawa E, Smith HM. Radiographic anatomy of the paranasal sinuses. IV. Caldwell view. Arch Otolaryngol. 1968;87 (3): 311-22. Pubmed citation
2. Jr RBJ, FACR BJMMDP, Osborn AG et-al. Diagnostic Imaging: Emergency: Published by Amirsys. Lippincott Williams & Wilkins. ISBN:1931884765. Read it at Google Books - Find it at Amazon
3. Caldwell, E.W.: Skiagraphy of the Accessory Sinuses of the Nose, Amer J Roentgen 5:569-574, 1918
4. John Lampignano, Leslie E. Kendrick. Bontrager's Textbook of Radiographic Positioning and Related Anatomy. (2017) ISBN: 9780323399661

The occipitomental (OM) or Waters view is an angled PA radiograph of the skull, with the patient gazing slightly upwards.

It can be used to assess for facial fractures, as well as for acute sinusitis. In general, radiographs of the skull and facial bones are rapidly becoming obsolete, being replaced by much more sensitive CT scans.

the patient is erect facing the upright detector
the chin is raised until the mento-mandibular line (MML) is perpendicular to the receptor (OML will be 37° from receptor)
ensure patient's head is straight

posteroanterior projection
centering point
- the beam is exiting at the acanthion
collimation
- superior to the skin margins
- inferior to include the most inferior aspects of the skull
- lateral to include the skin margin
orientation
detector size
exposure
SID
grid
- yes (this can vary departmentally)

ADVERTISEMENT: Supporters see fewer/no ads

the petrous ridge should be inferior to the maxillary sinuses
assess for rotation via the assessments of the coronoid process symmetry
generally, the base of the mandible and the occiput will be superimposed

learn your skull positioning lines, it makes for reading position guides a lot easier
guarantee that the patient is not 'hunched' over when they are being examined. This can cause an artifact from the shoulders and the patient is more likely to be rotated; it is best to move the chair up close to the detector so they are sitting up straight for the image
use a side marker and regularly place in PA. Skulls can get tricky with figuring out which side is which. Many vendors tend to 'flip' images to make them appear AP

History and etymology

This view was first described by Charles A. Waters and C. W. Waldron, American radiologists in 1915 3.

1. Berry. Diagnostic Radiology. Jaypee Brothers Medical Publishers (P) Ltd. ISBN:8180616363. Read it at Google Books - Find it at Amazon
2. John Lampignano, Leslie E. Kendrick. Bontrager's Textbook of Radiographic Positioning and Related Anatomy. (2017) ISBN: 9780323399661
3. Waters CA, Waldron CW. Roentgenology of the accessory nasal sinuses describing a modification of the occipito-frontal position. AJR Am J Roentgenol. 1915 Feb;2:633-39.

Waters' view (also known as the occipitomental view) is a radiographic view of the skull. It is commonly used to get a better view of the maxillary sinuses. An x-ray beam is angled at 45° to the orbitomeatal line. The rays pass from behind the head and are perpendicular to the radiographic plate. Another variation of the waters places the orbitomeatal line at a 37° angle to the image receptor. It is named after the American radiologist Charles Alexander Waters.

Waters' view

Method of obtaining Waters' view

SpecialtyRadiology

[edit on Wikidata]

Waters' view can be used to best visualise a number of structures in the skull.

Maxillary sinuses.
Frontal sinuses, seen with an oblique view.
Ethmoidal cells.
Sphenoid sinus, seen through the open mouth.
Odontoid process, where if it is just below the mentum, it confirms adequate extension of the head.

The frontal sinus may not show the frontal sinus in detail.[1]

Interpretation of results

Pathology	Observation
None (Normal)	Odontoid process lies exactly below mentum. Maxillary sinuses are more radiolucent than orbits.
Maxillary sinusitis[2]	Differentiating pathology in maxillary sinus Maxillary sinus shows radiopacity.[2] Mucous membrane shows thickening.[2] Air-fluid level may be observed if the radiograph is taken in "head-up" position.[2] It is not seen in radiograph taken in lying down position. The concavity of fluid opacity points upwards.
Polyp	Maxillary sinus shows radiopacity; which is present despite of the position in which the radiograph is taken. Usually, the radiopacity has convexity pointing upward.
Malignancy	Onhgren's line Sinus is radioopaque. Sometimes, destruction of walls of sinus is seen and is diagnostic of malignancy Distance between antero-lateral wall of maxilla and coronoid process of the mandible is measured. If it is increased on one side, it indicates involvement of infratemporal fossa by the malignancy. This is called Handousa's sign. Prognosis of malignancy is determined by position of tumour on basis Onhgren's line.

Typically, the x-ray beam is angled at 45° to the orbitomeatal line.[3] Another variation of the waters places the orbitomeatal line at a 37° angle to the image receptor,[4] or 30°.[5]

Waters' view is named after the American radiologist Charles Alexander Waters.[6] It is also known as the occipitomental view.[5]

^ Freeman, M. Brandon; Harshbarger, Raymond J. (2010). "44 - Fractures of the Frontal Sinus". Plastic Surgery Secrets Plus (2nd ed.). Mosby. pp. 291–294. doi:10.1016/B978-0-323-03470-8.00044-2. ISBN 978-0-323-03470-8.
^ a b c d Ruprecht, Axel; Lam, Ernest W. M. (2014). "26 - Paranasal Sinus Diseases". Oral Radiology - Principles and Interpretation (7th ed.). Mosby. pp. 472–491. doi:10.1016/B978-0-323-09633-1.00026-2. ISBN 978-0-323-09633-1.
^ Butler, Paul; Mitchell, Adam W. M. (Oct 28, 1999). Applied Radiological Anatomy. p. 97. ISBN 9780521481106.
^ Merrill's Atlas of Radiographic Positioning and Procedures. Vol. 2. p. 328.
^ a b Archer-Arroyo, Krystal; Mirvis, Stuart E. (2020). "1.2 - Radiological Evaluation of the Craniofacial Skeleton". Facial Trauma Surgery - From Primary Repair to Reconstruction. Elsevier. pp. 16–31. doi:10.1016/B978-0-323-49755-8.00010-4. ISBN 978-0-323-49755-8.
^ Chiu, Tor Wo (2019). Stone's plastic surgery facts : a revision guide (4 ed.). Boca Raton, FL: CRC Press. ISBN 978-1-315-18567-5. OCLC 1060523898.