MRI Elbow Joint Anatomy ligaments, tendon Common Elbow Pathologies on MRI

MRI Elbow Joint Anatomy

1. Bones

The elbow joint is formed by three bones:

• Humerus (upper arm)

• Ulna (forearm — medial side)

• Radius (forearm — lateral side)

Articulations:

• Humeroulnar joint: hinge movement (flexion/extension)

• Humeroradial joint: rotational movement

• Proximal radioulnar joint: supination/pronation

2. Ligaments

These provide stability to the elbow joint.

• Ulnar Collateral Ligament (UCL) / Medial Collateral Ligament (MCL)
  ➤ Prevents valgus stress (seen in throwing injuries)

• Radial Collateral Ligament (RCL) / Lateral Collateral Ligament (LCL)
  ➤ Prevents varus stress

• Annular Ligament
  ➤ Wraps around the radial head and holds it in place during rotation

3. Tendons

Tendons connect muscle to bone.

• Common Extensor Tendon (lateral epicondyle)
  ➤ Muscles for wrist extension (affected in Tennis Elbow)

• Common Flexor Tendon (medial epicondyle)
  ➤ Muscles for wrist flexion (affected in Golfer's Elbow)

• Distal Biceps Tendon (inserts on radial tuberosity)
  ➤ Elbow flexion and supination

• Triceps Tendon (inserts on olecranon)
  ➤ Elbow extension

4. Function

• Flexion/Extension (hinge action)

• Supination/Pronation (rotational movement)

• Stability for lifting, pushing, and rotation of the forearm

• Coordination between shoulder and wrist movements

MRI Appearance of Elbow Anatomy

Sequences:

• T1W: anatomy and bone marrow

• T2/STIR: fluid, edema, pathology

• PD FS: tendons, ligaments, cartilage

Common Elbow Pathologies on MRI

🔹1. Lateral Epicondylitis (Tennis Elbow)

• Degeneration or partial tear of the common extensor tendon

• T2 hyperintensity, tendon thickening, peritendinous edema

🔹 2. Medial Epicondylitis (Golfer’s Elbow)

• Involves common flexor tendon

• Similar MRI findings as above, but on the medial side

🔹 3. UCL Tear (Thrower’s Elbow)

• Common in athletes (baseball pitchers)

• Partial/complete tear; seen as discontinuity or high T2 signal in UCL

🔹 4. Biceps Tendon Tear (Distal)

• High T2 signal and gap at radial insertion

• May show tendon retraction

🔹 5. Triceps Tendon Tear

• Rare; seen in bodybuilders or trauma

• Disruption at olecranon insertion

🔹 6. Elbow Effusion

• Fluid in the joint capsule

• Non-specific, may indicate trauma, infection, or arthritis

🔹 7. Osteochondritis Dissecans (Capitellum)

• Common in adolescents

• Cartilage and subchondral bone injury seen on sagittal/axial T2

🔹 8. Ligament Injuries

• LCL or annular ligament sprains/tears

• May show increased signal, irregular contour, or avulsion

🔹 9. Nerve Compression (e.g., Cubital Tunnel Syndrome)

• Ulnar nerve compression at the elbow

• T2 hyperintensity, swelling of nerve

🔹 10. Fractures & Bone Contusions

• Seen as marrow edema on T2W/STIR

• Cortical disruption for fracture

 Summary Table

Structure	Function	MRI Pathology
UCL	Valgus stress resistance	Partial/complete tear
RCL	Varus stress resistance	Injury or laxity
Common Extensor Tendon	Wrist extension	Lateral epicondylitis
Common Flexor Tendon	Wrist flexion	Medial epicondylitis
Biceps/Triceps Tendons	Flexion/extension	Tendon rupture
Bones (humerus, ulna, radius)	Structure, motion	Fractures, OCD
Annular Ligament	Radial head stability	Subluxation, tear

What is Dynamic Angio in MRI? Why is MRI Brain with Dynamic Venography with Contrast done?

What is Dynamic Angio in MRI?

Dynamic Angiography in MRI (commonly referred to as Dynamic Contrast-Enhanced MRA or Time-Resolved MRA) is a specialized MRI technique used to visualize blood vessels dynamically over time—i.e., it captures a series of images as contrast flows through the vascular system.

Why it's called "Dynamic":

• Unlike static MRA (single snapshot), dynamic MRA captures multiple time frames after contrast injection.

• This allows visualization of arterial, capillary, and venous phases of blood flow—important for evaluating vascular timing, flow patterns, and pathology.

Why is MRI Brain with Dynamic Venography with Contrast done?

This is usually ordered when the clinician suspects a vascular abnormality involving the veins or sinovenous system of the brain. Here’s why:

1. Detect Cerebral Venous Thrombosis (CVT)

• Blood clots in venous sinuses may not show on non-contrast MRI.

• Dynamic contrast-enhanced MR venography shows how blood flows through the venous system, revealing blockages or slow flow.

2. Assess Arteriovenous Malformations (AVMs) or Fistulas

• Dynamic sequences show timing of contrast filling, helping differentiate between arteries and veins.

• Helps visualize abnormal connections or early venous drainage, characteristic of AVMs.

3. Evaluate Intracranial Hypertension

• Conditions like idiopathic intracranial hypertension (IIH) may involve transverse sinus stenosis, which is better seen with dynamic venography.

4. Detailed Mapping Before Surgery or Interventions

• Provides precise anatomy and timing of blood flow, guiding neurosurgical or endovascular planning.

Summary:

Technique	Purpose
Dynamic MRI Angio	Time-resolved imaging of arteries and/or veins during contrast injection.
MRI Brain with Venography (Dynamic Contrast)	Evaluates brain veins and sinuses over time — to detect clots, AVMs, fistulas, or venous stenosis.

MRI Brain Plain Venogram (Non-Contrast MRV)

1. MRI Brain Plain Venogram (Non-Contrast MRV)

➤ Technique:

• Typically done using Time-of-Flight (TOF) or Phase Contrast (PC) sequences.

• No contrast agent is used.

➤ Advantages:

• Non-invasive: No need for IV contrast.

• Useful for screening or follow-up of known conditions.

• Safe for patients with renal impairment or allergies to contrast.

➤ Limitations:

• May miss slow-flowing blood, especially in distal sinuses or small veins.

• Can be prone to artifacts (especially TOF in-plane flow saturation).

• Difficult in patients with motion or metallic implants.

2. Contrast-Enhanced MR Venogram (CE-MRV)

➤ Technique:

• Uses Gadolinium-based contrast agent.

• 3D T1-weighted imaging post-contrast injection (timed to venous phase).

➤ Advantages:

• More accurate visualization of venous structures, especially small veins.

• Less prone to flow-related artifacts.

• Can evaluate both anatomy and pathology like thrombosis or malformations better.

➤ Limitations:

• Requires IV access and contrast agent, which is contraindicated in:

  • Patients with GFR <30 (renal failure)

  • Known gadolinium allergy

• Slightly more expensive and time-consuming.

🎯 Clinical Indications for MR Venography:

• Suspected Cerebral Venous Sinus Thrombosis (CVST)

• Vascular malformations

• Evaluation of intracranial hypertension

• Follow-up of known venous pathology

MRI Defecography Report Template

📝 Sample MRI Defecography Report Template

Patient Name:                                                                   Age/Sex:
Referring Physician:

Clinical Indication: Chronic constipation, pelvic organ prolapse, incomplete evacuation, etc.

Technique:

MRI Defecography was performed in the supine position. The rectum was distended with ~120–180 ml of ultrasound gel. Dynamic sequences were obtained at rest, during squeeze, strain, and defecation.

Findings:

1. Rectum:

• At rest: Normal / Redundant / Dilated

• During defecation: Normal emptying / Incomplete evacuation

• Rectocele: Present / Absent – Size (e.g., 2.5 cm)

• Intussusception: Yes / No – Describe level

• Mucosal prolapse: Present / Absent

2. Anal Canal:

• Length: ___ cm

• Sphincter integrity: Intact / Disrupted (internal/external)

• Anismus: Yes / No – (Failure of relaxation noted)

3. Pelvic Floor Descent:

• Pubococcygeal Line (PCL) reference used.

• Perineal descent: Mild / Moderate / Severe (e.g., >3 cm below PCL)

4. Anterior Compartment (Bladder/Urethra):

• Cystocele: Yes / No – Grade (I/II/III)

• Urethral hypermobility: Present / Absent

5. Middle Compartment (Uterus/Vagina):

• Uterine prolapse: Yes / No

• Vaginal vault descent: Yes / No – Degree

6. Posterior Compartment:

• Enterocele: Yes / No – Bowel loop between vagina and rectum

Impression:

• Findings suggest a ___ (e.g., moderate rectocele with internal intussusception and pelvic floor dyssynergia).

• Recommend correlation with clinical symptoms and pelvic floor physiotherapy or surgical consultation.

MRI prostate plain, and contrast, What is the Function of the Prostate?

1. What is the Function of the Prostate?

The prostate is a small gland (about the size of a walnut) located below the bladder in men and surrounds part of the urethra.

Main functions:

• Produces seminal fluid: This fluid mixes with sperm from the testes to form semen.

• Nourishes and protects sperm: The fluid from the prostate contains enzymes, zinc, and citric acid that support sperm function.

• Aids ejaculation: During ejaculation, the prostate contracts to help propel semen into the urethra.

2. Why Do MRI Prostate Plain (Non-Contrast)?

Plain MRI of the prostate (also called non-contrast or multiparametric MRI) is used as a non-invasive diagnostic tool.

Reasons:

• Evaluate prostate anatomy and size

• Detect tumors: Especially suspicious areas that may indicate prostate cancer.

• Assess lesions: Determine if a lesion is likely to be benign or malignant.

• Guide biopsies: Helps target areas that need tissue sampling.

MRI prostate plain typically includes:

• T2-weighted imaging: Excellent for viewing the prostate’s internal zones.

• Diffusion-weighted imaging (DWI): Detects how water molecules move in tissue, helping find cancer.

• Apparent diffusion coefficient (ADC): Quantifies DWI.

• Sometimes, spectroscopic imaging.

Many centers prefer non-contrast multiparametric MRI (mpMRI) as the initial step for screening or evaluating prostate issues.

3. Why Do MRI Prostate With Contrast (Dynamic Contrast Enhanced MRI – DCE-MRI)?

MRI with contrast (using gadolinium-based agents) is done when:

• Further clarification of a lesion is needed.

• Higher suspicion of cancer is present.

• Evaluating cancer spread (staging).

• Checking vascularity of a lesion (cancers typically show early enhancement).

• Monitoring after treatment (e.g., after surgery, radiotherapy).

Dynamic Contrast Enhanced (DCE) imaging helps:

• Detect fast-enhancing areas (which may indicate aggressive tumors).

• Improve PI-RADS scoring (used to assess prostate lesions).

MRI Defecography MRI Defecography Protocol (Basic).

 MRI Defecography (also called MR Defecography or Dynamic Pelvic Floor MRI) is a specialized MRI study used to evaluate the structure and function of the pelvic floor muscles during defecation. It's particularly useful for patients with chronic constipation, incontinence, pelvic organ prolapse, or a sense of incomplete evacuation.

🔍 Purpose

MRI Defecography helps assess:

• Pelvic organ prolapse (rectocele, cystocele, enterocele)

• Rectal intussusception

• Anismus (failure of anal sphincter to relax)

• Pelvic floor dyssynergia

• Perineal descent

🧪 Procedure Overview

1. Patient Preparation:

   • Mild laxatives may be used before the exam.

   • Patients are often asked to avoid eating for a few hours prior.

2. Intraluminal Contrast:

   • The rectum is filled with ultrasound gel or jelly to simulate stool.

   • Sometimes, the vagina or bladder is also filled for better visualization of all compartments.

3. MRI Imaging:

   • Images are acquired at rest, squeeze, strain, and defecation phases.

   • A true sagittal plane is primarily used.

   • Additional axial and coronal planes may be used for anatomical detail.

✅ Advantages

• Non-invasive

• No ionizing radiation

• Detailed soft tissue contrast

• Multi-compartment evaluation (anterior, middle, posterior pelvic compartments)

📊 Typical MRI Sequences Used

• T2-weighted fast spin echo (static anatomy)

• Balanced steady-state free precession (for dynamic phases)

• Cine imaging during defecation for motion assessment

🩺 Clinical Indications

• Suspected complex pelvic floor disorders

• Failed conventional treatment for constipation or incontinence

• Prior to surgical planning for pelvic floor repair

📷 MRI Defecography Protocol (Basic)

Sequence	Plane	Purpose
T2 FSE	Axial/Sagittal	Static soft tissue anatomy
Balanced SSFP (TrueFISP/FIESTA)	Sagittal	Dynamic imaging at rest, squeeze, strain, defecation
Cine MR	Sagittal	Video loop for functional assessment
Optional T1	Axial	For detecting fat or hemorrhage

📊 Infographic Idea for Radiographic Gyan

Title: "MRI Defecography: A 360° Look at the Pelvic Floor"

Sections:

1. What is MRI Defecography?

   • Purpose and advantages

2. How is it done?

   • Step-by-step with icons (gel injection, squeeze, strain, defecate)

3. Anatomical Areas Assessed

   • Rectum, bladder, uterus/vagina

4. Common Findings

   • Rectocele, intussusception, enterocele, perineal descent

5. When is it needed?

   • Symptoms that indicate the scan

MRI sequences and its use.

 MRI (Magnetic Resonance Imaging) sequences are various techniques used in MRI scans to obtain different types of images and contrast. Each sequence is designed to highlight different tissues or conditions in the body. Here’s a rundown of some commonly used MRI sequences:

1. T1-Weighted Imaging (T1WI)

• Purpose: Provides high-resolution images of anatomical structures.
• Appearance: Fat appears bright; water and cerebrospinal fluid (CSF) appear dark.
• Uses: Good for assessing anatomy and structural details. Often used post-contrast to evaluate lesions or tumors.

2. T2-Weighted Imaging (T2WI)

• Purpose: Highlights differences in water content.
• Appearance: Water and CSF appear bright; fat and most solid tissues appear darker.
• Uses: Useful for identifying edema, inflammation, and many pathologies. It’s often used to assess brain lesions and spinal cord abnormalities.

3. Proton Density Imaging (PD)

• Purpose: Measures the density of hydrogen protons in tissues.
• Appearance: Provides contrast based on the density of protons rather than their relaxation times.
• Uses: Good for evaluating structures where the contrast between tissues is less pronounced but still informative.

4. Fluid-Attenuated Inversion Recovery (FLAIR)

• Purpose: Suppresses the signal from fluids (like CSF) to highlight lesions.
• Appearance: CSF is dark, while lesions in the brain are bright.
• Uses: Effective for identifying lesions in the brain, particularly useful in diagnosing multiple sclerosis and other demyelinating diseases.

5. Gradient Echo (GRE)

• Purpose: Provides images with varying contrast depending on the echo time (TE) and repetition time (TR).
• Appearance: Sensitive to magnetic field inhomogeneities.
• Uses: Useful for imaging blood products, calcifications, and sometimes for functional MRI (fMRI).

6. Echo Planar Imaging (EPI)

• Purpose: Fast imaging technique that acquires images quickly.
• Appearance: High speed and can be prone to artifacts.
• Uses: Common in functional MRI (fMRI) and diffusion tensor imaging (DTI).

7. Diffusion Weighted Imaging (DWI)

• Purpose: Measures the diffusion of water molecules in tissues.
• Appearance: Areas with restricted diffusion (e.g., acute stroke) appear bright.
• Uses: Important for diagnosing strokes and assessing the integrity of white matter.

8. Diffusion Tensor Imaging (DTI)

• Purpose: An extension of DWI that maps the diffusion of water in multiple directions.
• Appearance: Provides information on the orientation and integrity of white matter tracts.
• Uses: Used in research and clinical practice to study brain connectivity and white matter abnormalities.

9. Susceptibility Weighted Imaging (SWI)

• Purpose: Enhances the visibility of blood products and calcifications.
• Appearance: Highlights areas with different magnetic susceptibilities.
• Uses: Effective for detecting microbleeds, venous structures, and calcifications.

10. Magnetic Resonance Angiography (MRA)

• Purpose: Visualizes blood vessels without the need for contrast injection.
• Appearance: Shows blood vessels as bright structures against a darker background.
• Uses: Non-invasive assessment of vascular structures, such as arteries and veins.

Each MRI sequence has specific applications and is chosen based on what the clinician is looking to diagnose or evaluate.