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1
Q

What is lateral to the femoral ring?

§ Femoral vein
§ Femoral artery
§ Femoral nerve
§ Medial side of the rectus abdominis 
§ Inguinal ligament
A

§ Femoral vein

*The answer to this question is found in the e-loops

2
Q

A 20-year old medical student with occasional heartburn will show which of the following readings on a manometer?

A

A

3
Q

A woman presented with dysphagia for both solids and liquids with progressive food regurgitation. Which manometry reading is associated with her condition?

A

B

4
Q

A 48-year old female with pain in her joints, localized thickness, and tightness in fingers and toes. Which manometry reading is appropriate for his condition?

A

C

5
Q

A patient presented with retrosternal chest pain and dysphagia of both solid andliquid. Barium swallow x-ray showed,Choose the appropriate esophageal manometry

A

D

6
Q

What supplies the hepatic flexure?

§ Right colic artery
§ Middle colic artery

A

§ Right colic artery

  • Dr. Naryana: “Hepatic flexure is supplied by the right colic artery”. Hepatic flexure is part of the ascending colon and is supplied predominantly by the right colic artery, hence the other name of the flexure is “right colic” flexure
7
Q

Which of the following is true regarding the surface anatomy of the abdominal wall?

A

The transpyloric plane traverses the duodenojejunal junction

8
Q

Which nerve will be damaged during appendectomy?

§ Ilioinguinal nerve
§ Femoral nerve
§ Obturator nerve

A

§ Ilioinguinal nerve

9
Q

A salivary gland biopsy showed myxoid stroma and epithelia. Diagnose.

A

Pleomorphic adenoma

10
Q

A 62-year old smoker, presented with unilateral painless neck swelling of 3 months’ duration, associated with an ulcer in the undersurface of the tongue. What would a biopsy show?

§ Islets of malignant squamous cells
§ Clusters of malignant glands
§ Enlarged plasmoblasts
§ Reed-Sternberg cells

A

§ Islets of malignant squamous cells

11
Q

Parotidectomy to a patient resulted in weakness of orbicularis oris muscle. Which nerve was damaged?

§ Facial nerve
§ Hypoglossal nerve
§ Auriculotemporal nerve

A

§ Facial nerve

12
Q

A male suffered from road rage and was lying supine with hemaperitoneal fluid. In which space the fluid will be found?

§ Hepatorenal recess
§ Pouch of Douglas
§ Subphrenic recess

A

§ Hepatorenal recess

13
Q

What is responsible for taste sensation in the anterior 2/3 of the tongue?
§ Chorda tympani
§ Glossopharyngeal nerve

A

§ Chorda tympani

14
Q

Secretions of the submandibular salivary gland are affected by injury to which nerve?

§ Chorda tympani
§ Glossopharyngeal nerve

A

§ Chorda tympani

15
Q

Nerves innervating the striated muscles of the pharynx are located in which nucleus?

§ Nucleus ambiguus
§ Dorsal vagal nucleus
§ Nucleus tractus solitarii

A

§ Nucleus ambiguus

  • The nucleus ambiguus controls the motor innervation of ipsilateral muscles of the soft palate, pharynx, larynx and upper esophagus
16
Q

Resting pressures in the pharynx, upper esophageal sphincters, body of the esophagus, and lower esophageal sphincter were measured. Which of the following best estimate these pressures respectively?

A

0 → 50 → 0 → 30

17
Q

A patient who underwent vagotomy goes out with his friends to eat in a restaurant. In which phase will gastrin secretion be inhibited?

§ When he thinks about the food
§ When the bolus of food reaches his stomach

A

§ When he thinks about the food

18
Q

What is the embryonic origin of the inner lining of small intestines?

§ Endoderm
§ Ectoderm
§ Splanchnic mesoderm
§ Somatic mesoderm

A

§ Endoderm

19
Q

Which nerve has fibers in the tonsillar bed?

§ Glossopharyngeal nerve
§ Lingual nerve

A

§ Glossopharyngeal nerve

20
Q

What is a characteristic feature of the esophagus?

A

Nonkeratinized stratified squamous epithelium

21
Q

Which nerve supplies the muscles attached to the pterygomandibular raphe?

§ Facial and vagus
§ Mandibular and vagus
§ Maxillary and mandibular

A

§ Facial and vagus

  • “The superior pharyngeal constrictor muscle is innervated by the pharyngeal branch of the vagus nerve via the pharyngeal plexus. Motor innervation of the buccinator is from the buccal branch of the facial nerve (cranial nerve VII). Sensory innervation is supplied by the buccal branch (one of the muscular branches) of the mandibular part of the trigeminal (cranial nerve V).”
22
Q

Which recording of vagal inhibitory fibers (VIF) and vagal excitatory fibers (VEF) will be seen with receptive opening of the lower esophageal sphincter?

§ Increased firing of VIF and absent firing of VEF
§ Both VIF and VEF action potentials are increased
§ Both VIF and VEF action potentials are decreased

A

§ Increased firing of VIF and absent firing of VEF

23
Q

Where is the synapse between the pre and postganglionic sympathetic fibers to the stomach?

§ Celiac ganglion
§ Sympathetic ganglion
§ Submucosal ganglion
§ Myenteric plexus

A

§ Celiac ganglion

24
Q

Which lymph nodes are the last to receive stomach lymphatics before reaching cisterna chyli?

A

Celiac lymph nodes

25
Q

An RCT was done to assess the reduction of stroke in high risk individuals of clopidogrel/aspirin compared to aspirin only. Both drugs combined resulted in 2.4% improvement and aspirin only resulted in 1.9% improvement. Calculate NNT

A

200

  • NNT= 1/ARR and since ARR= 0.024 – 0.019= 0.005 then NNT= 1/0.005=200
26
Q

What is the mechanism of action of dicyclomine?

A

Muscarinic antagonist

27
Q

What has maximum activity at pH 3?

A

Pepsin

28
Q

What activates all pancreatic enzymes?

A

Trypsin

29
Q

What causes decreased secretion from gastric glands?

A

Acidic pH in the antrum

30
Q

What is the site of sensory neurons to the stomach?

§ Dorsal root ganglion
§ Greater splanchnic nerve
§ Myenteric plexus
§ Submucosal plexus

A

§ Dorsal root ganglion

31
Q

A 57-year old lady complained of epigastric pain when eating for the past year. Endoscopy showed erythematous plaques in the lower esophageal mucosa. Biopsy showed basal squamous epithelia, taller papillae, and intraepithelial neutrophils with few eosinophils. Diagnose.

§ Reflux esophagitis
§ Adenocarcinoma
§ Barrett’s esophagus

A

§ Reflux esophagitis

32
Q

A 54-year old woman presented with a gastric polyp that showed tubular morphology and low grade dysplasia. Diagnose.

§ Adenoma
§ Adenocarcinoma

A

§ Adenoma

33
Q

Which of the following is a paracrine hormone released from enterochromaffin cells?

A

Histamine

34
Q

Which of the following may be increased in gastritis?

§ Plasma cells
§ Undifferentiated cells
§ Submucosal plexus
§ Neck mucous cells

A

§ Plasma cells

35
Q

Which of the following is related to vitamin B12 deficiency?

A

Parietal cells

36
Q

What increases if parietal cells are hyperactive?

§ Intrinsic factor
§ Gastrin

A

§ Intrinsic factor

37
Q

Which of the following is found in the isthmus of the gastric gland?

§ Undifferentiated cells
§ Mucus neck cells

A

§ Undifferentiated cells

38
Q

A 67-year old female presented with 9 Kg weight loss, fatigue, and nausea. Biopsy showed erosion and signet cells. Diagnose.

§ Diffuse carcinoma
§ GIST
§ Adenoma

A

§ Diffuse carcinoma

39
Q

Which tumor will stain positive for C-Kit (CD117)?

A

GIST

40
Q

During surgery, the posterior boundary of the omental foramen was damaged and there was profuse bleeding. What is the source?

§ Inferior vena cava
§ Portal vein
§ Gastroduodenal artery

A

§ Inferior vena cava

41
Q

Endoscopy in a 54-year old woman showed pyloric stenosis. Biopsy showed necrosis, inflammation, and granulation tissue with H. pylori. What is the most likely diagnosis?

A

Peptic ulcer

42
Q

What is a prominent feature of the empty stomach?

A

Gastric rugae

43
Q

Which substance has receptors on oxyntic cells and inhibits their activity?

A

Somatostatin

44
Q

What is responsible for receptive relaxation of both lower esophageal sphincter and stomach?

A

VIP

45
Q

Which drug prevents gastric damage caused by NSAIDs?

A

Misoprostol

46
Q

What inhibits H+/K+ ATPase pump?

A

Omeprazole

47
Q

A patient with epilepsy using phenytoin and he had peptic ulcer. Which drug should be avoided?

§ Omeprazole
§ Famotidine
§ Magnesium
§ Misoprostol

A

§ Omeprazole

48
Q

Hepatocytes around this vessel tend to be affected first due to low oxygen in the blood. What describes this vessel?

§ Central vein
§ Hepatic artery 
§ Hepatic vein
§ Portal vein
§ Sublobular vein
A

§ Central vein

49
Q

What are the only hepatitis viruses that have immunoprophylaxis?

§ HAV and HBV
§ HAV only
§ HBV only
§ HCV only
§ HBV and HCV
A

§ HAV and HBV

50
Q

What mediates damage in autoimmune hepatitis?

§ Cytotoxic T cells
§ Antibody-mediated cellular toxicity

A

§ Cytotoxic T cells

51
Q

Which of the following describes the discontinuous endothelium facilitating nutrient absorption to hepatocytes?

A

Sinusoids

52
Q

How would fluid in the liver region reach the lower part of the greater sac?

A

Paracolic gutter

53
Q

Primary biliary cirrhosis is characterized by immunological destruction of bile ducts. What immune effectors are usually found around bile ducts?

§ Helper T cells
§ Natural killer cells
§ Neutrophils

A

§ Helper T cells

54
Q

Which vessel is used to follow segment VII of the liver?

A

Right hepatic vein

55
Q

Through which of the following does the liver develop?

A

Ventral mesogastrium

56
Q

What features allow the portal triad to act as a functional portal lobule?

§ Bile acids from the central vein to the portal tract
§ Blood distribution from portal triad to central vein
§ Oxygen distribution
§ Nutrients distribution

A

§ Bile acids from the central vein to the portal tract

  • Confirmed by Dr. Naryana
57
Q

A 40-year old woman with 5 days’ history of fever, jaundice, liver tendernes and hepatomegaly. Bilirubin was 189 and AST was 1200, while GGT was normal (but ALP high). Diagnose.

A

Acute viral hepatitis

58
Q

Where does the lymphatics start in the liver?

A

Periportal space of Mall

59
Q

What is the function of Ito cells in inflammation?

A

Collagen synthesis

60
Q

Man had a screening test before applying for a job. Everything was normal except ALT and AST were slightly elevated. Diagnose.

A

Chronic viral hepatitis

61
Q

What causes edema in patients with liver cirrhosis?

§ Decreased plasma oncotic pressure
§ Increased plasma oncotic pressure
§ Decreased tissue oncotic pressure
§ Increased tissue oncotic pressure

A

§ Decreased plasma oncotic pressure

62
Q

An 18-year old lady presented with fever, nausea, and flu-like symptoms. Her urine was dark and she just returned from India 10 days ago. What will be the findings?

A

High ALT and AST

63
Q

What is interface hepatitis?

§ Inflammation and necrosis of hepatocytes at the limiting plate § Inflammation of zone 3 hepatocytes
§ Inflammation of zone 2 hepatocytes

A

§ Inflammation and necrosis of hepatocytes at the limiting plate

64
Q

A 22-year old female with painless jaundice and flu-like illness had normal direct bilirubin and total bilirubin high. Urine analysis showed yellow urine with urine specific gravity of 1030, negative RBCs and urobilinogen, and trace amounts of sugar. She later became asymptomatic as the flu resolved. Diagnose.

A

Gilbert syndrome

65
Q

Why should a patient on cyclosporine for AML avoid grapefruit juice?

§ Because it inhibits cyclosporine metabolism
§ Because it increases risk of organ rejection

A

§ Because it inhibits cyclosporine metabolism

66
Q

What is the function of ligandins in heme metabolism?

§ Binding bilirubin in hepatocytes
§ Binding biliverdin
§ Chelating iron

A

§ Binding bilirubin in hepatocytes

67
Q

A 20-year old female with fever and jaundice had very high urobilinogen in her urine. Diagnose.

A

Hemolytic jaundice

68
Q

A 40-year old woman who has been taking contraceptive pills for years presented with a liver mass. Partial lobectomy was done and the mass was solid, well circumscribed and uniform in color. Diagnose.

A

Hepatic adenoma

69
Q

What determines secretion of bile from the liver?

§ Concentration of bile salts in portal vein
§ Concentration of bile salts in gallbladder

A

§ Concentration of bile salts in portal vein

70
Q

A 45-year old diabetic male who is obese was seen to have liver inflammation. What is the most likely cause?

§ Non-alcoholic steatohepatitis
§ Alcoholic liver disease
§ Hepatitis B
§ Hepatitis C

A

§ Non-alcoholic steatohepatitis

71
Q

Which of the following is a marker for hepatocellular carcinoma?

A

α-fetoprotein

72
Q

Which of the following is a complication of portal HTN?

A

Esophageal varices

73
Q

A 67-year old alcoholic had a 7 cm mass seen in CT with pleomorphic nuclei, brown inclusions in cytoplasm, and moderate size cells. Diagnose.

A

Hepatocellular carcinoma

74
Q

What imaging modality is used to diagnose air below diaphragm?

§ Chest X-ray while standing
§ Chest X-ray in supine position
§ CT of the abdomen
§ Plain abdominal X-ray in supine position

A

§ Chest X-ray while standing

75
Q

Which nerve root is responsible for referred pain of cholecystitis to the right shoulder?

§ C3-C4
§ C6-C7

A

§ C3-C4

76
Q

Which of the following is a cholangiocarcinoma at the confluence of right and left hepatic bile ducts?

A

Klatskin tumor

77
Q

What is a complication of acute pancreatitis?

A

Pseudocyst

78
Q

Which biochemical changes predominate in active Crohn’s disease?

§ Increased lipid oxidation
§ Increased thermogenesis
§ Reduced resting metabolic rate

A

§ Increased lipid oxidation

  • “Patients with active Crohn’s disease had increased resting energy expenditures, enhanced lipid oxidation and decreased diet-induced thermogenesis compared to controls. The effect of lipid peroxidation was directly related to disease activity. Yet, increased lipid oxidation was even seen in patients with inactive Crohn’s disease. Accelerated mucosal cell turnover may also increase nutrient requirements in IBD.”
79
Q

A patient presented with migratory erythema, anemia, and diabetes. Diagnose.

A

Glucagonoma

80
Q

Zollinger-Ellison syndrome is associated with an intractable peptic ulcer. What pancreatic tumor is of concern?

A

Gastrinoma

81
Q

Oxidation of iron will lead to the production of which radical?

A

Hydroxyl radical

82
Q

What is the mechanism of fat saponification in pancreatitis?

A

Free fatty acids and calcium

83
Q

A 45-year old male presented with visible jaundice. He had no pain but suffered from weight loss and noticed pale stool. Diagnose.

A

High bilirubin and ALP

84
Q

A 78-year old man with jaundice and nausea without abdominal pain. US revealed a dilated gallbladder and intrahepatic biliary ducts with no gallstones. Diagnose.

A

Pancreatic adenocarcinoma

85
Q

What imaging modality is used to differentiate between cystic and solid lesions?

§ Ultrasound
§ CT
§ 99mTc liver scan
§ X-ray

A

§ Ultrasound

86
Q

What is the surface marking of the fundus of gallbladder?

A

Tip of the right 9th costal cartilage

87
Q

Which of the following is an indicator of intrahepatic and extrahepatic obstruction?

§ GGT
§ ACP
§ ALT
§ AST

A

§ GGT

88
Q

Which of the following contributes to Calot’s triangle?

§ Cystic duct
§ Common bile duct
§ Pancreatic duct
§ Sphincter of Oddi
§ Sphincter of Boyden
A

§ Cystic duct

89
Q

Which component is added in a bile conjugation reaction?

A

Glycine

90
Q

What is made by microorganisms?

A

Secondary bile acids

91
Q

Which structure contains the tail of the pancreas?

A

Lienorenal ligament

92
Q

The bile duct opens into which part of the duodenum?

§ Descending
§ Ascending
§ Superior

A

§ Descending

93
Q

A 49-year old woman with acute myeloid leukemia on chemotherapy had acid-fast cysts in her stool. What is the organism?

§ Cryptosporidium spp.
§ Strongyloides

A

§ Cryptosporidium spp.

94
Q

Which drug is a muscarinic receptor antagonist used for motion sickness?

A

Hyoscine

95
Q

What is the mechanism responsible for absorption of glucose from enterocytes?

A

Secondary active transport

96
Q

Which drug is a D2 receptor antagonist with central and GI effect?

A

Metoclopromide

97
Q

Which laxative increases peristalsis by stimulating the enteric nerves?

A

Senna

98
Q

A 7-year old body with diarrhea and abdominal pain improved considerably after taking wide spectrum antibiotics. Jejunal biopsy shows numerous foamy histiocytes in the lamina propria and stained positive with PAS stain. What is the diagnosis?

§ Whipple disease
§ Tropical sprue
§ Autoimmune enteropathy

A

§ Whipple disease

99
Q

What allows transport of antigens by pinocytosis?

A

M cells

100
Q

What is the source of free fatty acids in a well-fed person?

A

Chylomicrons

101
Q

What helps the micelle release its contents near the cell membrane of enterocytes?

A

High hydrogen concentration

102
Q

Why care should be taken when managing a starving boy?

A

Because his urea cycle is abnormal

103
Q

What will be used in early starvation?

§ Amino acids in the blood
§ Liver glycogen

A

§ Amino acids in the blood

  • Liver glycogen is used in initial fasting.
104
Q

A 19-year old female patient presented with a rash, weight loss, voluminous diarrhea despite good appetite. Investigation revealed anemia and anti- transglutaminase?

§ Small bowel biopsy
§ D-xylose absorption test
§ Stimulation secretion test
§ Small intestine x-ray screening

A

§ Small bowel biopsy

105
Q

Which artery is eroded by a peptic ulcer?

§ Gastroduodenal artery
§ Left gastric artery
§ Hepatic artery
§ Short gastric artery

A

§ Gastroduodenal artery

106
Q

What is a characteristic of the ileum?

A

Peyer’s patch

107
Q

The highest concentration of goblet cells is found in which part of the intestine?

§ Colon
§ Ileum

A

§ Colon

  • Ileum has the most numerous goblet cells in the SMALL INTESTINE, but the
    colon has the most numerous goblet cells OVERALL
108
Q

A mucosal biopsy in a celiac disease patient revealed high T lymphocytes within surface epithelium. What is the type?

A

CD8+ T cells

109
Q

What is responsible for the formation of T-cell lymphoma in celiac patients?

A

CD8+ T cells

110
Q

What tissue component is associated with initiating damage in celiac disease and responsible for the presence of antibodies?

A

Th1 cells

111
Q

What is involved in the production of tissue transglutaminase and deamidated gliadin in celiac disease?

§ B-lymphocytes
§ Helper T cells
§ Macrophages

A

§ B-lymphocytes

112
Q

What is related to the superior duodenal flexure?

§ Fundus of the gallbladder
§ Neck of the gallbladder
§ Common bile duct
§ Main pancreatic duct

A

§ Fundus of the gallbladder

113
Q

Which bacteria causes hemolytic uremic syndrome?

§ Verocytotoxic E. coli
§ Enterotoxigenic E. coli
§ Salmonella typhi

A

§ Verocytotoxic E. coli

114
Q

What is the predominant flora located in the duodenum?

§ Enterobacter faecalis
§ Escherichia coli
§ Salmonella

A

§ Enterobacter faecalis

115
Q

A 32-year old pregnant lady on long term steroids for her Crohn’s disease developed meningitis. She has a history of soft cheese consumption. What is the cause?

§ Listeria monocytogenes
§ Amoeba
§ Vibrio

A

§ Listeria monocytogenes

116
Q

Administration of 100 g of glucose to a patient increased his glucose levels by 20%. However, administration of 200 g of lactose didn’t elevate his glucose levels. What can explain the findings?

A

Absence of brush border lactase enzyme

117
Q

A 72-year old man presented with watery diarrhea after colorectal surgery, what is the causative bacterial agent?

A

C. difficile

118
Q

A 24-year old male is recently diagnosed with lymphoma of both duodenum and jejunum with a history of watery diarrhea responding to diet modification. What did he have?

A

Celiac disease

119
Q

A patient with celiac disease on a gluten-free diet was hard to manage and biopsy showed lymphoid aggregates of T cells in his small intestine. Diagnose.

A

Enteropathy-associated T cell lymphoma

120
Q

What are the cytokines that mediate tissue damage in both Crohn’s and celiac disease?

A

IFN-γ and TNF-α

121
Q

A 23-year old Indian farmer presented with high fever for 5 days. On examination, he had bradycardia, leukopenia, and rose-spot rash on his abdomen. Diagnose.

A

Salmonella

122
Q

A girl developed food poisoning with bloody diarrhea and self-limiting abdominal pain after eating chicken salad. What is the causative organism?

A

Campylobacter jejuni

123
Q

What factor protects the stomach from colonization of bacteria?

§ Acidic pH
§ IgA
§ Proteolytic enzymes
§ Mucus

A

§ Acidic pH

124
Q

The segmental contractions (haustrations) in the descending colon are more intense than those in the ascending colon. The sigmoid colon showed the weakest segmental contractions of these. What is the reason?

A

Increased transit time

125
Q

A young girl presented with diarrhea. Protozoa were seen in her stool. Identify the organism.

A

Giardia lamblia

126
Q

What is the gold standard for laboratory diagnosis of Clostridium difficile associated diarrhea?

§ Detection of toxin B in stool
§ PCR
§ Culture stain
§ Detection of toxin A in stool

A

§ Detection of toxin B in stool

127
Q

What method is used for neutralization of C. difficile toxin B?

§ Agglutination test
§ Latex agglutination
§ PCR
§ Tissue culture
§ Antibody immunofluorescence
A

§ Agglutination test

128
Q

What is the sensory innervation of the anal mucosa below the pectinate line?

§ Inferior rectal nerve
§ Pelvic splanchnic nerve
§ Lumbar splanchnic nerve
§ Pudendal nerve

A

§ Inferior rectal nerve

129
Q

Which part of the intestine has no villi and small tubular glands?

A

Colon

130
Q

What gene will be affected in a patient with colon cancer with no family history?

§ p53
§ K-ras
§ APF

A

§ p53

131
Q

What is the most significant mutation for progression of adenoma to colorectal carcinoma?

§ Tp53 inactivation mutation
§ APC
§ Hypomethylation
§ Hypermethylation

A

§ Tp53 inactivation mutation

132
Q

What helps modulate antibiotic-associated colitis?

§ Toxin B of C. difficile
§ Capsule of C. difficile
§ Polysaccharide antigen of C. difficile
§ Toxin A of C. difficile

A

§ Toxin B of C. difficile

133
Q

Which of the following describes a flat tumor with serrated architecture and dysplastic cells removed from the ascending colon of a 51-year old male?

§ Sessile adenoma
§ Familial polyposis coli
§ Stage III colorectal cancer
§ Lynch syndrome
§ Pedunculated adenoma
§ Peutz Jeghers polyposis / syndrome 
§ Stage IV colorectal cancer
A

§ Sessile adenoma

134
Q

A 29-year old woman recently diagnosed with colorectal cancer with dark pigmented patches on her lips. Diagnose.

A

Peutz Jeghers polyposis / syndrome

135
Q

A patient presented with colon cancer with no previous records of adenomatous polyps. His father had colorectal cancer and his sister had uterine cancer. What is the mutation?

A

MLH1 mutation

136
Q

A patient had 5 siblings (3 brothers and 2 sisters) diagnosed with HNPCC. What describes this family?

§ One of the parents has MSH2 mutation
§ Both of the parents are carriers to an APC mutation
§ One of the parents carry an APC mutation
§ Two of parents are carriers for MLH1 gene

A

§ One of the parents has MSH2 mutation

137
Q

Which artery if ligated will affect the blood supply to the sigmoid colon?

§ Superior rectal artery
§ Inferior mesenteric artery

A

§ Superior rectal artery

  • “Occlusion of the inferior mesenteric artery does not always result in irreversible ischaemia of the descending and sigmoid colon, because the marginal artery of the colon usually receives an adequate supply from the left branch of the middle colic artery. Moreover, the sigmoid arteries may be supplied by the superior rectal artery, which anastomoses with the middle and inferior rectal arteries. When ischaemia does occur, it is usually maximal in the proximal descending colon because this region is furthest from the collateral arterial supplies.”