GI Flashcards
What are the three major phases of swallowing?
The first phase has three
Normal swallowing in the dog: a cineradiographic study VRU 1979
Oropharyngeal, esophageal and gastroesophageal
Oropharyngeal: oral, pharyngeal, pharyngoesophageal phase.
Describe the three oropharyngeal stages in the oropharyngeal phase of swallowing.
Normal swallowing in the dog: a cineradiographic study VRU 1979
Oral: voluntary stage. Stripping action of tongue to organize a bolus in the oropharynx. Bolus formation at the oropharynx elicits the next 2 stages
Pharyngeal: Peristaltic cranial contraction of pharynx and propulsion of bolus from the tongue into the laryngopharynx. Blockage of egresses (tongue - plunger like action to roof of mouth to block oropharynx, pharyngeal arch - nasopharynx, and epiglottis - larynx). At time of pharynx contraction - cricopharyngeal sphincter opened and allowed passage of bolus into the esophagus.
Pharyngoesophageal stage - closure of cricopharyngeal sphincter and relaxation of pharynx, epiglottis, tongue and pharyngeal arch.
Describe the different types of esophageal peristalsis
Normal swallowing in the dog: a cineradiographic study VRU 1979
Primary: Triggered by oropharyngeal phase
1) Swallow reflex –> esophageal peristaltic wave
2) Swallow –> bolus accumulates in cranial esophagus for multiple swallows until second bolus pushes forward
Secondary: Triggered mechanically by luminal esophageal distension and tactile stimuli
1) Swallowed bolus resides in esophagus until esophagus is stimulated to move
2) Multiple boluses from several swallow accumulate in proximal esophagus and trigger peristaltic wave
How is a pharyngeal contraction judged as adequate?
Normal swallowing in the dog: a cineradiographic study VRU 1979
Takes approximately 2-4 frames at a rate of 60 frames per second, and results in the entire bolus moving past the cricopharyngeal sphincter
What muscles make up the cricopharyngeal sphincter?
Normal swallowing in the dog: a cineradiographic study VRU 1979
Quantitative valuation of pharyngeal function in the dog VRU 41.5
cricopharyngeous and thyropharyngeous
Morphologic vs functional causes of dysphagia?
Quantitative evaluation of pharyngeal function in the dog. VRU 41.5
Morphologic: foreign body, neoplasia, trauma
Functional: inability of muscles to relax, incoordination of ontraction, flaccidity of muscles
What are the most common neoplastic transformation of spirocerca? What are the most common radiographic findings?
TPDCT perfusion characteristics of spirocercosis induced esophageal nodules in non-neoplastic versus neoplastic canine cases.” VRU. 56.3 2015
Esophageal Osteosarcoma is most common. (fibrosarcoma and chondrosarcoma less likely). Radiographic findings: aortic aneurysm, caudal thoracic spondylitis, caudodorsal mediastinal mass
What are common characteristics of neoplastic vs non-neoplastic nodules in spirocerca esophageal lesions? (Comment on: contour, mineralization, necrosis, compare contrast enhancement between the two, and and the surrounding esophagus)
TPDCT perfusion characteristics of spirocercosis induced esophageal nodules in non-neoplastic versus neoplastic canine cases.” VRU. 56.3 2015
Non-neoplastic: smooth, no mineralization, necropurulent pockets (74% - 18% CSA), higher contrast enhancement when compared to neoplastic nodules (significant in all phases), higher enhancement of adjacent esophageal tissues (precontrast and early arterial phases) Neoplastic: irregular, mineralization (93%- 17% of CSA), necropurulent pockets (46% - 4% of CSA), contrast enhancement (lesser degree than non-neoplastic), esophagus had higher HU value than neopalstic nodule for all pahses
What nerves help govern swallowing?
Trigeminal, facial, glossopharyngeal, vagus and hypoglossal
In dogs with cricopharyngeal acahlasia - which portion of swallowing is significantly delayed?
What other portions of swallowing phase are delayed, but not significant between normal and abnormal dogs?
Quantitative evaluation of pharyngeal function in the dog. VRU 41.5
Opening and closure of the cranial esophageal sphincter (cricopharyngeal sphincter) in both liquid and kibble swallows.
Liquid: (0.09 - N, vs 0.31s - Abnormal)
Kibble: 0.26s - N, vs 0.44s - Abnormal
Caudal contraction of pharynx and epitlottic reopening times. –> why it should be called dyssynchrony instead!
What is approximate timing (from onset of swallow - the closure of the epiglottis) until CES opening and closure in normal vs abnormal dog (dysphagic)
Quantitative evaluation of pharyngeal function in the dog. VRU 41.5
Normal dog:
Opening: 0.09-0.1
Closing: 0.26-0.33
Dysphagic dog
Opening: 0.31-0.37
Closing: 0.44-0.6
Which muscles make up the upper esophagela sphincter (the cricopharyngeal arch). What nerves innervate these muscles?
Oropharyngeal dysphagias in the dog – cinefluorographic analysis of experimentally induced and spontaneously occurring swallowing disorders. I. Oral stage and pharyngeal stage dysphagias.
Thyropharyngeus, and cricopharyngeus
Parts of glossopharyngeal/vagus – the pharyngoesophageal nerve
What are fluoroscopic findings consistent with dysfunction of the oral stage of the oropharyngeal phase of swallowing?
Oropharyngeal dysphagias in the dog – cinefluorographic analysis of experimentally induced and spontaneously occurring swallowing disorders. I. Oral stage and pharyngeal stage dysphagias.
Variable reduction in tongue movement.
Difficulty forming a bolus
Contrast retention at the base of tongue - due to poor plunger like action of the tongue during following phases.
NO difference in ability to handle kibble vs liquids (vs CP dysphagia)
What are fluoroscopic findings consistent with dysfunction of the pharyngeal stage of the oropharyngeal phase of swallowing?
Oropharyngeal dysphagias in the dog – cinefluorographic analysis of experimentally induced and spontaneously occurring swallowing disorders. I. Oral stage and pharyngeal stage dysphagias.
1) No problem with bolus formation
2) Incomplete pharyngeal contraction - residual gas and contrast medium after CP relaxation
3) Slow contraction (cranial to caudal motion)
4) Retention of contrast in piriform recesses, pharyngeal opening
5) CP still coordinates well with pharyngeal motion
How to differentiate between primary pharyngeal stage and cricopharyngeal stage dysphagias?
Oropharyngeal dysphagias in the dog – cinefluorographic analysis of experimentally induced and spontaneously occurring swallowing disorders. I. Oral stage and pharyngeal stage dysphagias.
Cricopharyngeal: transient pharyngeal outpouchings due to forceful contraction of pharynx against closed cricopharyngeal arch.
Pharyngeal dysphagia: no deformation of cricopharyngeal passage
What is definition of chalasia and achalasia? (In regards to cricopharyngeal dysphagias)
Chalasia: failure to close
Achalasia: failure to open
What are some findings that may be seen in cricopharyngeal sphincter malfuction? (3)
Oropharyngeal dysphagias in the dog: a cinefluorographic analysis of experimentally induced and spontaneously occurring swallowing disorders. II. Cricopharyngeal stage and mixed oropharyngeal dysphagias
1) premature opening of cricopharyngeal passage and closure before emptying
2) delayed opening - cricopharyngeal arch begins to relax when pharynx is receding
3) Total absence of coordination between cricopharyngeal passage and pharyngeal contraction
What are some findings that may be seen in mixd oropharyngeal dysphagia?
Oropharyngeal dysphagias in the dog: a cinefluorographic analysis of experimentally induced and spontaneously occurring swallowing disorders. II. Cricopharyngeal stage and mixed oropharyngeal dysphagias
Simultaneous poor pharyngeal contractility and cricopharyngeal non-relaxation
Weak pharyngeal contraction resulting in contrast retention
What is importance in distinguishing between mixed pharyngeal/cricopharyngeal and cricopharyngeal dysphagia?
Oropharyngeal dysphagias in the dog: a cinefluorographic analysis of experimentally induced and spontaneously occurring swallowing disorders. II. Cricopharyngeal stage and mixed oropharyngeal dysphagias
Cricopharyngeal dysphagia - can be surgically treated with myotomy
If mixed - will result in severe aspiration pneumonia due to retention of large amounts of food within the pharynx resulting in aspiration.
According to the article
Initial influence of right vs left lateral recumbency on radiographic findings of duodenal gas on subsequens.nt survey VD projections of canine abdomen. VRU 56.1
Which lateral should be performed first if you are concerned about pyloric/duodenal obstruction?
Left lateral - more likely to have duodenal gas on the VD projection
When performing left lateral projection first - resulted in increased gas within the duodenum on all projections
Why do they suspect that performing a left lateral first (in an abdominal sries) is more likely to result in more gas present within the duodenum?
Initial influence of right vs left lateral recumbency on radiographic findings of duodenal gas on subsequent survey VD projections of canine abdomen. VRU 56.1
When the left lateral is performed - gas goes to the pyloric region. In humans, when enough gas is present in the pylorus - it will open for short periods of time to allow passage of gas into the duodenum.
When comparing two groups (group 1 that had left lateral performed first and group 2 that had right lateral performed first) - which was more likely to have gas present within the duodenum on the right lateral projection?
Initial influence of right vs left lateral recumbency on radiographic findings of duodenal gas on subsequent survey VD projections of canine abdomen. VRU 56.1
Group 1 - left lateral performed first - 43% vs group 2 that had 4%
When performing left lateral projection first - resulted in increased gas within the duodenum on all projections
How likely are foreign bodies to be found in the duodenum?
How likely are linear foreign bodies found to include the duodenum?
Initial influence of right vs left lateral recumbency on radiographic findings of duodenal gas on subsequent survey VD projections of canine abdomen. VRU 56.1
1) - 4-24%
2) - 84%
Duodenal changes in cases of pancreatitis?
Initial influence of right vs left lateral recumbency on radiographic findings of duodenal gas on subsequent survey VD projections of canine abdomen. VRU 56.1
lateral displacement of the duodenum
widening of the pyloroduodenal junction
abnormal gas distention of the duodenum
What are primary and secondary causes of a mesenteric volvulus?
Imaging diagnosis: Use of multiphasic CE-CT for diagnosis of mesenteric volvulus in a dog. VRu 55.1
Primary: Altered Gi motility, high fiber diets
Secondary: adhesions, hernia, pregnancy, previous surgery, GDV, foreign body, IBD, intussusception.
What is the CT whirl sign? When is it seen?
Spiral appearance (barber pole) to vessels, intestines, and fat, secondary to a volvulus.
Imaging diagnosis: Use of multiphasic CE-CT for diagnosis of mesenteric volvulus in a dog. VRU 55.1
In humans, what are common CT findings that may lead to a diagnosis of volvulus?
Imaging diagnosis: Use of multiphasic CE-CT for diagnosis of mesenteric volvulus in a dog. VRU 55.1
Whirl sign Global dilation of the small intestines Bowel wall thickening Enlarged veins Alterations of mesenteric vessels Beak shape of the intestines at the site of the volvulus. Thrombi within the vessels
What are the US characteristics of primary GI carcinomas vs lymphoma?
Imaging diagnosis: US appearance of small bowel metastasis from canine mammary carcinoma VRU 55.2
Intestinal carcinomas: transmural thickening of intestinal wall with complete loss of normal intestinal layers, changes in normal wall echogenicity decreased motility with or without obstruction, lymphadenopathy.
Lymphoma: diffuse, or solitary hypoechoic intestinal mass with transural thickening and loss of wall layering. Can also appear as diffuse infiltrative disease with wall thickening.(Cats - muscularis layer, dogs - not specific layer)
What are most common GI tumor types in dogs?
Imaging diagnosis: US appearance of small bowel metastasis from canine mammary carcinoma VRU 55.2
Adenocarcinoma
Lymphoma
What is frequency of occurrence of mammary carcinoma in dogs?
Imaging diagnosis: US appearance of small bowel metastasis from canine mammary carcinoma VRU 55.2
50% of tumors in intact females
Where does mammary carcinoma frequently metastasize to in dogs vs humans?
Imaging diagnosis: US appearance of small bowel metastasis from canine mammary carcinoma VRU 55.2
Lymphatic vessels to regional lymph nodes and to the lungs.
Dogs: Intestinal mets without specific layer being identified, skeletal and cardiac mets.
Women: lungs, liver, bones, soft tissue, brain and adrenal glands. GI mets are rare - involve diffuse mural thickening of the intestinal wall.
In the article: Imaging diagnosis: US appearance of small bowel metastasis from canine mammary carcinoma VRU 55.2. Where were the mets found, and which layer did they affect? How did they appear?
Multiple, oval to round well defined/marginated, hypoechoic nodules between 0.3-0.7cm.
Found in the muscularis layer of the small intestine (jejunum). The remaining wall layers were unaffected. The thickness of the jejunal wall was normal, except where nodules were found where they measured 0.6cm.
What is hyperechoic linear band paralleling colonic serosal layer in dogs represent?
Prevalence and significance of US colonic muscularis hyperechoic band paralleling serosal layer in dogs. VRU 56.6
Thickening of the fibrous tissue in the myenteric plexus of the muscularis
What are clinical signs of dogs with hyperechoic linear band paralleling the colonic serosal layer in dogs?
Prevalence and significance of US colonic muscularis hyperechoic band paralleling serosal layer in dogs. VRU 56.6
Usually NOT GI related.
What histology does a linear, hyperechoic structure in the mucosal layer of the GI represent in cats?’
sonographic appearance of intestinal mucosal fibrosis in cats. VRU 51.4
inflammatory cell infiltrates including eosinophils
What clinical significance did the linear, hyperechoic structure in mucosal layer of GI represent?
sonographic appearance of intestinal mucosal fibrosis in cats. VRU 51.4
All cats had some GI upset
What other changes did cats with linear hyperechoic structure in the mucosal layer have?
What clinical significance did the linear, hyperechoic structure in mucosal layer of GI represent?
Also had wall thickening, altered wall layering (increased echogenicity of mucosa, thick submucosa or muscularis layer).
No complete loss of wall layers.
What could US appearance of small bowel infarction appear like in a cat?
US diagnosis of small bowel infarction in a cat VRU 44.1
Progressive thickening of small intestinal loop (over 48 hours), with eventual loss of normal wall layers - diffusely hypoechoic
What are CT findings of bowel infarction?
US diagnosis of small bowel infarction in a cat VRU 44.1
diffuse/focal bowel wall thickening bowel dilation intramural gas intramural edema peritoneal fluid or gas
A proposed inflammatory condition in cats that mimics neoplasia, eosinophils are the most abundantly involved cell type.
JFMS 15.2
Feline gastrointestinal eosinophilic sclerosing fibroplasia.
Bacteria has been cultured from Feline gastrointestinal eosinophilic sclerosing fibroplasia in only about 56% of cases. What bacteria is most commonly isolated?
JFMS 15.2
Meth resistant Staph Aureus
