Physical Address

304 North Cardinal St.
Dorchester Center, MA 02124

Neuroendocrine Tumors

KEY FACTS Terminology Terms such as carcinoid and islet cell tumor are decreasing in use, in favor of well-differentiated (low-grade) or poorly differentiated (high-grade) NETs GI tract: Most common primary site (74%), followed by bronchopulmonary (24%) Small bowel most common (~ 60%); ileum in majority Pancreas: < 1% of all NETs Imaging Patients with known or suspected NET require multimodality imaging approach, combining anatomic (morphologic) and…

Peritoneal Inclusion Cyst

KEY FACTS Terminology Loculated fluid trapped within peritoneal adhesions, typically surrounding ovary Imaging Most often in pelvis (can rarely occur elsewhere) Ultrasound Loculated cystic mass with "spiderweb" pattern due to peritoneal adhesions reflecting from ovary Fine septations throughout collection Normal ovary at center or lateral margin of cyst No solid mural or septal nodule to suggest malignancy Usually anechoic fluid, but can have internal echoes due…

Postoperative Free Air and Fluid

KEY FACTS Terminology Presence of intraperitoneal or body wall gas/fluid following surgery Imaging Pneumoperitoneum is common imaging finding after surgery on both plain radiographs and CT CT has 2x sensitivity of plain films for detection of pneumoperitoneum Pneumoperitoneum is seen on CT in 87% of patients following uncomplicated laparotomy at 3 days post surgery and 50% of patients at 6 days No upper limit to normal…

Barotrauma

KEY FACTS Terminology Alveolar rupture caused by elevated transalveolar pressure during mechanical ventilation Imaging CT definitive test for presence & source of extraluminal gas Pleural spaces, mediastinum, subcutaneous, intra- and retroperitoneal, bowel wall Radiographic findings Pneumothorax – Radiolucent gas between visceral and parietal pleura – Inferiorly displaced costophrenic angle on supine films (deep sulcus sign) Pneumomediastinum – Radiolucent streaks outlining heart and trachea Pneumoperitoneum – Best…

Foreign Bodies

KEY FACTS Imaging Ingested foreign bodies Commonly affect children, developmentally challenged or psychiatric patients, and inebriated adults Most ingested foreign bodies traverse GI tract without problem: < 1% cause obstruction or perforation – Elongated or sharp objects may impact at point of intestinal narrowing or sharp angulation Foreign bodies vary in radiopacity and conspicuity on radiography vs. CT For most nonsharp foreign bodies, begin with visual inspection…

Eosinophilic Gastroenteritis and Esophagitis

KEY FACTS Terminology Inflammatory disease of GI tract characterized by tissue eosinophilia that can involve all layers of wall "Eosinophilic gastroenteritis" is misnomer; can affect any portion of GI tract Requires 4 criteria for diagnosis Presence of GI symptoms Biopsy proof of eosinophilic infiltration of 1 or more areas of GI tract Absence of eosinophilic involvement of multiple organs outside GI tract Absence of parasitic infestation…

HIV/AIDS

KEY FACTS Terminology Abdominal opportunistic infections and neoplasms resulting from HIV/AIDS-related immunodeficiency Imaging Liver and spleen Small hypodense nodules may be microabscesses Larger hypodense lesions might be infectious, but AIDS-related lymphoma should be considered Pneumocystis may result in tiny calcifications Biliary tree Cholangitis or acalculous cholecystitis caused by opportunistic infections Stomach, small bowel, and large bowel Wall thickening raises concern for opportunistic infection, which can involve…

Postoperative and Postprocedure Bowel Imaging

KEY FACTS Imaging Afferent loop (AL) syndrome AL becomes obstructed by adhesions, recurrent tumor, internal hernia, etc. CT is better than fluoroscopic studies for this diagnosis Colonoscopy and other endoscopic procedures Prevalence of complications is 1-2% CT shows perforation best and more safely Enterectomy and anastomosis Low rectal anastomoses are especially prone to ischemia, stricture, leak, and fistulas Small bowel anastomoses Side-to-side anastomosis may simulate obstruction…

Imaging of Bariatric Surgery

KEY FACTS Imaging CT and upper GI radiography have complementary roles Laparoscopic adjustable gastric banding (LAGB) procedure (a.k.a. "lap band") Less effective for sustained weight loss Complications: Less common and less varied May be too tight or too loose Band may erode into stomach or esophagus Sleeve gastrectomy (gastric sleeve) 75% of stomach is removed by dividing stomach along its long axis – Complications: Less or…

Iatrogenic Injury: Feeding Tubes

KEY FACTS Terminology Patient injury caused by improper feeding tube placement Feeding tubes Small, soft enteric tubes Some with flexible metallic tips Tip of feeding tube should be located beyond stomach (distal duodenum or jejunum) Nasogastric tubes Large bore, moderately stiff Used for temporary gastric and bowel decompression Tip placed in pylorus can cause outlet obstruction Gastrostomy and jejunostomy tubes Balloon-tipped catheters should not be placed…

Abdominal Abscess

KEY FACTS Terminology Localized abdominal collection of pus or infected fluid Imaging CT is imaging test of choice : Low density, loculated, encapsulated fluid collection with peripheral rim enhancement Simple fluid density (0-10 HU) or slightly hyperdense Internal gas in absence of intervention/drainage highly suspicious for infected collection "Abscess" suggests discrete, drainable fluid collection: Differentiate from ill-defined inflammation and fluid that is not drainable (i.e., phlegmon)…

Abdominal Trauma

KEY FACTS Imaging CT of chest, abdomen, and pelvis can be performed in < 1 minute of scan time Multiplanar, multiphasic CECT shows extent of bowel and solid visceral injuries and bleeding Evaluation of brain and spine injuries can be done quickly in the same setting "Sentinel clot": High density (> 60 HU); near the source of bleeding "Active extravasation": Isodense to enhanced arteries Active bleeding…