GI Imaging Densities l Xray allows visualization of

GI Imaging

Densities l X-ray allows visualization of different densities -Air -Fat -Water -Metal

Visualization of the Esophagus l Different density required for visualization i. e. : contrast

Contrast Agents l Water Soluble – Gastrografin – Low-osmolality l Inert – Barium sulfate

Single vs. Double Contrast l Improved mucosal visualization

Fluoroscope l Real-time -ray video l Multiple sequential images l Spot films x

Barium Studies l (Video) Esophogram l Barium Swallow l UGI series l Modified Barium Swallow

Gastroesophageal Reflux

GERD & Barium l Visualization of refluxing barium l Patient position l Valsalva l Usefulness is arguable

GERD Secondary Signs l Hiatal Hernia (HH) l Cricopharyngeus muscle spasm l Reflux esophagitis l Benign stricture l Barrett’s esophagus l Aspiration pneumonia

Hiatal Hernia l Extension of stomach into chest through esophageal hiatus l 2 types: – Sliding 95% – Para-esophageal 5% § l May Not associated with GERD be more prominent when supine

Cricopharyngeous Muscle l Posterior wall of pharyngoesophageal junction l Normally relaxes with swallowing to allow passage of food l Incomplete relaxation can be seen as protective mechanism in GER patients l Smooth impression at C 5 -6 level

Cricopharyngeous Muscle Spasm

Reflux Esophagitis l Begins distally l Thickened folds l May have associated linear ulcers

Benign Stricture l Distal or mid-esophagus l Smooth walls l May be partially distensible

Barrett’s Esophagus l In approx. 10% of untreated reflux patients l Metaplasia of normal squamous epithelium to a gastric columnar epithelium l Nodular or granular mucosa l Look for focal ulceration, stricture, and cancer (15% or 30 x increase)

Barrett’s Esophagus

Aspiration Pneumonia l Appearance will vary with amount of aspirate, patient position, reaction to aspiration l Often bilateral, associated atalectasis l Posterior and basal areas more common

Aspiration Pneumonia

Aspiration

Esophageal Cancer

Detection l Barium studies are not as sensitive as endoscopy, but more readily available l Suspect cases referred on to endoscopy l CT, MRI not suitable for screening

Barium Swallow Patterns 1. Annular constricting l Most common l Many variations Polypoid mass 3. Infiltrative 2. l In submucosa, may simulate benign stricture 4. Ulcerated mass

Esophageal Cancer

Esophagobronchial fistula

Tumor Staging l CT most commonly used l Endoscopic ultrasound in some centers

Computed Axial Tomography

Computed Axial Tomography

CT Staging l Wall thickness l Infiltration of paraesophageal fat planes l Regional invasion (trachea, pleura, pericardium, vertebrae etc…) l Lymphadenopathy l Distant Metastases

Normal CT

Invasive Cancer

Endoscopic Ultrasound l Smaller lesions l Assess wall involvement

Esophageal Motility

Normal Motility l Best seen prone l 3 phases: – Oral, pharyngeal, esophageal

Esophageal Phase l Primary wave: – Initiated by swallowing reflex l Secondary Wave: – As response to esophageal distension

Normal Swallow

Abnormal Motility l Non-specific finding l Seen in reflux esophagitis, radiation injury, caustic ingestion, myxedema, diabetes mellitus…

Corkscrew esophagus l Tertiary esophageal waves – Non-propulsive – Corkscrew or beaded appearance

Scleroderma l Fibrosis of smooth muscle l Dilated esophagus with widely patent GEJ l Resultant reflux l Reflux esophagitis => ulceration => stricture (mild) => Barrett’s => neoplasm

Scleroderma

Achalasia l Diffusely decreased or absent peristalsis l Lower esophageal sphincter fails to relax l Smooth, tapered distal esophageal narrowing l Some passage of food in upright position

Achalasia

Neuromuscular Disorders l Most common => stroke l Parkinsonism, Alzheimer’s, multiple sclerosis, CNS neoplasms, traumatic injury l Modified barium swallow

Zenker’s Diverticulum

Zenker’s l Herniation at posterior midline above UES l Horizontal & oblique fibers of inferior constrictor muscles => Killian’s dehiscence l Associated incomplete cricopharyngeus muscle relaxation l Neck at superior aspect of sac l Midline, but lateral extension with growth

Zenker’s Diverticulum

Zenker’s Diverticulum