Chapter 135 - Medial arcuate ligament syndrome

Question 1

Median arcuate ligament syndrome first defined by

Answer 1

1971 Stanley and Fry

Question 2

MALS other names

Answer 2

1) celiac artery compression syndrome 2) Dunbar syndrome

Question 3

Clinical presentation of MALS

Answer 3

1) epigastric pain 2) nausea vomiting 3) weight loss 4) food fear 5) exercise pain 6) autonomic dysfunction 7) fibromyalgia 8) postural 9) orthostatic tachycardia syndrome

Question 4

First anatomic description of MALS done by

Answer 4

Lipshutz 1917

Question 5

First surgical release of MALS done by

Answer 5

Harjola 1963

Question 6

First description of MALS surgery with clinical benefit

Answer 6

Dunbar 1967

Question 7

Percentage of population with MALS and percentage of people that are symptomatic

Answer 7

24% of general population < 1% of that are symptomatic

Question 8

Embryological origin of MAL

Answer 8

Diaphragm from septum transversum –> descend from neck towards celiac axis week 9-12

Question 9

Anatomical location of the diaphragmatic crura

Answer 9

From L1-L4 anterior aspect projecting cephalad to join anterior longitudinal ligament of spine overlaying celiac axis

Question 10

Arcuate ligaments anatomic picture

Answer 10

FIGURE 135.1

Question 11

Pathophysiology of MALS theories

Answer 11

1) Gut ischemia theory: compression results in lack of circulation from celiac 2) steal theory: compression results in SMA steal and thereby small bowel ischemia 3) nerve overstimulation of celiac plexus causing splanchnic vasoconstriction 4) neurogenic hypothesis with pain fiber stimulation

Question 12

Epidemiology of MALS

Answer 12

20-60’s age Female:Male 3:1

Question 13

MALS in relation to breathing

Answer 13

Expiration –> aorta moves cephalad –> celiac plexus compressed by MAL Inspiration –> celiac artery moves away from MAL as aorta moves caudally

Question 14

Duplex criteria for MALS Moneta

Answer 14

1) peak expiratory > 200 cm/s 2) greater than resting and inspiratory velocities

Question 15

Gruber et al diagnostic criteria for MALS

Answer 15

1) end diastolic velocity > 350 cm/s 2) 210% change in pulse volume amplitude with inspiration and expiration 3) celiac deflection angle of 50 degrees Sensitivity 83% Specificity 100%

Question 16

Gastric exercise tonometry in MALS

Answer 16

Arterial gastric CO2 level before, during and after 10 min of submaximal exercise 1) PPI or H2 blocker given 2) measure baseline 3) 10 min exercise and 20 min recovery Positive test: 1) gastric arterial PCO2 gradient > 0.8 kPa after exercise 2) increase in gastric PCO2 from baseline to peak exercise 3) arterial lactate level < 8

Question 17

Treatment types for MALS

Answer 17

1) Celiac ganglion block 2) endovascular (not used anymore) 3) laparoscopic release/robot assist 4) open surgery

Question 18

Treatment algorithm of MALS

Answer 18

Multidisciplinary approach Laparoscopic/robotic MAL release with celiac ganglionectomy –> angioplasty/stenting –> vascular reconstruction

Question 19

Treatment success of laparoscopic or open surgery for MALS and recurrence

Answer 19

Success 50-70% Recurrence 5.7-6.8%

Question 20

Symptoms of celiac ganglion compression

Answer 20

1) nausea, vomoting 2) gastric dysmotility

Question 21

Composition of nerve fibers in celiac plexus

Answer 21

1) pain fibers 2) inhibitory motor fibers of stomach