Cervical Spine Obliques Radiology Tutorial

Summary

This tutorial focuses on cervical oblique projections in radiology, explaining how they are used to visualize the intervertebral foramina (IVFs) in the cervical spine. The video covers key techniques for positioning the patient at a 45-degree angle to the Bucky and adjusting the X-ray tube for optimal visualization. It highlights the differences between anterior and posterior obliques, the anatomical structures involved, and methods for identifying the side of the IVFs being viewed. The tutorial also provides insights into common challenges in interpreting these images and clinical considerations for accurate diagnosis.

Takeaways

• 😀 Cervical oblique projections are used to visualize the intervertebral foramen (IVFs) in the cervical spine.
• 😀 The IVFs in the cervical spine are oriented at a 15° anterior and 45° inferior angle relative to the coronal plane.
• 😀 Patient positioning at a 45° angle to the Bucky is crucial for optimal visualization of the IVFs, combined with a tube tilt.
• 😀 Oblique projections can be taken in anterior (AO) or posterior (PO) orientations, affecting the direction of the tube tilt.
• 😀 Left anterior obliques show the left side IVFs, while right anterior obliques show the right side IVFs.
• 😀 In posterior obliques, the opposite IVFs are visualized (e.g., left posterior oblique shows the right IVFs).
• 😀 Radiographic markers are often used to specify patient positioning (e.g., LPO, RPO), but careful observation can help deduce positioning.
• 😀 A trick to differentiate right and left structures on a radiograph is to draw a line dividing the posterior vertebral body, helping identify the side of the IVFs.
• 😀 The borders of the IVFs are defined by the pedicles, articular pillars, facet joints, and the intervertebral discs.
• 😀 Narrowing of the IVFs can be caused by conditions like facet joint arthrosis, disc herniation, and uncinate process degeneration.
• 😀 Oblique projections allow visualization of the pedicles, laminae, facet joints, and other cervical spine structures, but one side of the posterior arch is often more visible.
• 😀 Laminae can sometimes overlap with other structures in the cervical spine, so it's essential to understand how they appear in radiographs for accurate interpretation.

Q & A

What is the purpose of taking cervical oblique projections?

Cervical oblique projections are taken to visualize the intervertebral foramen (IVFs) in the cervical spine, as these structures are oriented at a 15° anterior and 45° inferior angle relative to the coronal plane.

What is the patient positioning for a cervical oblique projection?

The patient is positioned at a 45° angle to the Bucky to allow for adequate visualization of the intervertebral foramen. A tube tilt is also used to help achieve the correct imaging angle.

How do anterior and posterior oblique projections differ in terms of IVFs visualization?

In anterior oblique projections, the same side IVFs are visualized, while in posterior oblique projections, the opposite or contralateral IVFs are seen.

What does LPO stand for in the context of cervical oblique projections?

LPO stands for Left Posterior Oblique, which refers to the positioning of the patient for the oblique projection where the left side of the patient is positioned posteriorly against the Bucky.

How can you identify the IVFs in a cervical oblique projection?

The IVFs are identified as lucent holes along the posterior aspect of the cervical spine. The radiographic marker indicating the patient's left or right side helps determine which side's IVFs are being visualized.

How do you differentiate between anterior and posterior oblique projections when no markers are used?

You can deduce the side being visualized by drawing a line dividing the vertebral body, separating right and left structures. This helps in identifying which side's IVFs are visible.

Why are the pedicles seen on profile in a cervical oblique projection?

The pedicles are seen on profile because the X-ray beam is directed at a 90° angle to the pedicles, allowing them to appear as linear structures in the image.

What anatomical structures define the borders of the intervertebral foramen?

The borders of the intervertebral foramen are defined by the pedicles (posteriorly), the vertebral body and intervertebral disc (anteriorly), and the facet joints and articular pillars (posteriorly).

What is the role of the lamina in cervical oblique projections?

The lamina appears on the same side as the IVFs in oblique projections. However, the contralateral lamina can be visualized on the same side as the IVFs due to the overlap of structures.

How can you identify the level of the cervical spine in an oblique projection?

The level of the cervical spine is identified by observing anatomical landmarks such as the posterior arch of C1, and by counting downward to subsequent levels (C2, C3, etc.).