Dynamic Ultrasound Assessment of Celiac Artery Flow Velocity in Median Arcuate Ligament Syndrome Diagnosis.

BACKGROUND Median arcuate ligament syndrome (MALS) poses a considerable challenge in terms of diagnosis due to its manifestation of diverse symptoms linked to constriction of the median arcuate ligament surrounding the celiac artery. The present study introduces an earlier diagnostic modality using ultrasound measurements of the flow velocity of the celiac artery during the inspiratory and expiratory phases, with the latter being higher than the former, to avoid prolonged follow-up of postprandial symptomatology. CASE REPORT A 46-year-old female patient presented with acute postprandial abdominal pain, which was alleviated by analgesic medication. The findings from the physical examination and laboratory tests were within normal limits. Further investigations were conducted due to persistent symptoms, revealing an elevation in celiac artery flow velocity during expiration on ultrasound. The diagnosis of median arcuate ligament syndrome (MALS) was confirmed through contrast-enhanced CT and angiography. Subsequently, the patient underwent laparoscopic release of the median arcuate ligament, leading to alleviation of symptoms at the 1-year follow-up assessment. CONCLUSIONS Our case report highlights the importance of a dynamic imaging diagnostic strategy for MALS. When encountering challenging postprandial abdominal pain that is hard to diagnose, it could be crucial to utilize abdominal ultrasound to measure the flow velocity of the celiac artery. This approach may serve as a valuable screening method for identifying MALS and, subsequently, prompt the need for further diagnostic tests.

I saw the "hook" sign of median arcuate ligament syndrome.

The hook sign is a radiologic finding best appreciated on a sagittal view of the celiac artery with computed tomography (CT) that indicates compression of the celiac artery. It refers to the hooked-shape of the proximal celiac artery caused by extrinsic compression by the median arcuate ligament. When seen in a patient with concurrent abdominal symptoms, it suggests median arcuate ligament syndrome (MALS). We saw the sign in a 15-year-old male via duplex ultrasonography and abdominal CT. He underwent laparoscopic release of the median arcuate ligament and had full resolution of his symptoms at follow-up.

Examining the impact of median arcuate ligament-induced celiac artery compression on target vessel patency, long-term survival and device integrity in fenestrated and branched endovascular repairs.

OBJECTIVE: To evaluate the impact of celiac artery (CA) compression by median arcuate ligament (MAL) on technical metrics and long-term CA patency in patients with complex aortic aneurysms undergoing fenestrated/branched endograft repairs (F/B-EVARs). METHODS: Single-center, retrospective review of patients undergoing fenestrated/branched endovascular aortic aneurysm repairs and requiring incorporation of the CA between 2013 and 2023. Patients were divided into two groups-those with (MAL+) and without (MAL-) CA compression-based on preoperative computed tomography angiography findings. MAL was classified in three grades (A, B, and C) based on the degree and length of stenosis. Patients with MAL grade A had ≤50% CA stenosis measuring ≤3 mm in length. Those with grade B had 50% to 80% CA stenosis measuring 3 to 8 mm long, whereas those with grade C had >80% stenosis measuring >8 mm in length. End points included device integrity, CA patency and technical success-defined as successful implantation of the fenestrated/branched device with perfusion of CA and no endoleak. RESULTS: One hundred and eighty patients with complex aortic aneurysms (pararenal, 128; thoracoabdominal, 52) required incorporation of the CA during fenestrated/branched endovascular aortic aneurysm repair. Majority (73%) were male, with a median age of 76 years (interquartile range [IQR], 69-81 years) and aneurysm size of 62 mm (IQR, 57-69 mm). Seventy-eight patients (43%) had MAL+ anatomy, including 33 patients with MAL grade A, 32 with grade B, and 13 with grade C compression. The median length of CA stenosis was 7.0 mm (IQR, 5.0-10.0 mm). CA was incorporated using fenestrations in 177 (98%) patients. Increased complexity led to failure in CA bridging stent placement in four MAL+ patients, but completion angiography showed CA perfusion and no endoleak, accounting for a technical success of 100%. MAL+ patients were more likely to require bare metal stenting in addition to covered stents (P = .004). Estimated blood loss, median operating room time, contrast volume, fluoroscopy dose and time were higher (P < .001) in MAL+ group. Thirty-day mortality was 3.3%, higher (5.1%) in MAL+ patients compared with MAL- patients (2.0 %). At a median follow-up of 770 days (IQR, 198-1525 days), endograft integrity was observed in all patients and CA events-kinking (n = 7), thrombosis (n = 1) and endoleak (n = 2) -occurred in 10 patients (5.6%). However, only two patients required reinterventions. MAL+ patients had overall lower long-term survival. CONCLUSIONS: CA compression by MAL is a predictor of increased procedural complexity during fenestrated/branched device implantation. However, technical success, long-term device integrity and CA patency are similar to that of patients with MAL- anatomy.

Exploring celiac trunk parameters in median arcuate ligament syndrome: A CT study.

PURPOSE: To assess anatomical variations in the celiac trunk (Ct) in patients with Median Arcuate Ligament Syndrome (MALS) using computed tomography (CT). The primary objectives were to investigate the celiac trunk angle (CtA), origin level, length (CtL), and their relationships with the superior mesenteric artery (SMA) in MALS patients. Additionally, the study intended to evaluate gender differences in these parameters and explore correlations between variables. METHODS: Retrospectively, reports of abdominal CT scans taken between January 2018, and Sepmtember 2021, in the hospital image archive were screened vey two observers independently for MALS diagnosis. Parameters such as CtA, CtL, Ct-SMA distance, SMA angle (SMAA), and median arcuate ligament thickness (MALT) were measured. Statistical analyses were conducted using SPSS software. RESULTS: Among the 81 patients (25 females, 56 males), significant differences were observed in MALT between genders (p = 0.001). CtA showed a negative correlation with CtL and Ct-SMA (p < 0.001), and a positive correlation was found between CtL and Ct-SMA (p = 0.002). CtL was measured as 25 mm for the all group. Origin levels of Ct and SMA were evaluated in comparison to vertebral levels. Ct-SMA distance was relatively shorter (9.19 mm) compared to the literature. SMAA findings were consistent with normal population values. CONCLUSION: This study provided valuable insights into the anatomical parameters of the Ct ans SMA in MALS patients. Despite some differences compared to normal population parameters, no evidence supported the hypothesis of a superiorly placed Ct contributing to MALS.

Vascular compression syndromes in the abdomen and pelvis: a concise pictorial review.

Vascular compression syndromes are a diverse group of pathologies that can manifest asymptomatically and incidentally in otherwise healthy individuals or symptomatically with a spectrum of presentations. Due to their relative rarity, these syndromes are often poorly understood and overlooked. Early identification of these syndromes can have a significant impact on subsequent clinical management. This pictorial review provides a concise summary of seven vascular compression syndromes within the abdomen and pelvis including median arcuate ligament (MAL) syndrome, superior mesenteric artery (SMA) syndrome, nutcracker syndrome (NCS), May-Thurner syndrome (MTS), ureteropelvic junction obstruction (UPJO), vascular compression of the ureter, and portal biliopathy. The demographics, pathophysiology, predisposing factors, and expected treatment for each compression syndrome are reviewed. Salient imaging features of each entity are illustrated through imaging examples using multiple modalities including ultrasound, fluoroscopy, CT, and MRI.

A radio-anatomical study of median arcuate ligament syndrome: unveiling the morphology and morphometry of median arcuate ligament, celiac trunk, and superior mesenteric artery.

PURPOSE: In the context of medical literature, a significant lacuna exists in understanding median arcuate ligament syndrome (MALS). While clinical aspects are well documented, literature lacks a robust exploration of the anatomical relationship between the celiac trunk and the median arcuate ligament (MAL). METHODS: Morphometric parameters, including the vertebral level of MAL origin, MAL thickness, celiac trunk (CeT) origin level, diameter, and distances between CeT/Superior Mesenteric Artery (SMA) and the MAL center were observed on 250 CT angiograms. Cadavers (n = 11) were dissected to examine the same parameters and histo-morphological examination of MAL tissue was done. RESULTS: Radiological findings established average MAL thickness of 7.79 ± 2.58 mm. The celiac trunk typically originated at T12. The average distance between the celiac trunk and the MAL center was 1.32 ± 2.04 mm. The angle of the celiac trunk to the abdominal aorta was primarily obtuse. The average celiac trunk diameter was 5.53 ± 1.33 mm. Histological examinations revealed a diverse MAL composition, indicating variable mechanical properties. CONCLUSION: This study provides comprehensive morphometric data on the anatomical relationship between the MAL and the celiac trunk. In contrast to available literature which says the average MAL thickness of > 4 mm is an indicator of increased thickness, we observed much higher average thickness in the studied population. The findings contribute to a better understanding of normal anatomical variations which can serve as reference values for accurate radiological diagnosis of MALS. The histological examination revealed the heterogeneous nature of the MAL tissue composition, suggesting variable mechanical properties and functions in different regions.

Intraoperative assessment of blood flow using transabdominal ultrasound during laparoscopic surgery of celiac artery compression syndrome.

Surgical treatment of celiac artery (CA) compression syndrome (CACS) is to release the median arcuate ligament (MAL) by removing the abdominal nerve plexus surrounding CA. In laparoscopic surgery of CACS, objective intraoperative assessment of blood flow in CA is highly desirable. We herein demonstrate a case of laparoscopic surgery of CACS with use of intraoperative transabdominal ultrasound. A 52-year-old woman was presented with epigastric pain and vomiting after eating. Contrast-enhanced computed tomography demonstrated significant stenosis at the origin of CA. Doppler study of CA was also performed, and she was diagnosed as CACS. Laparoscopic surgery was performed, and the MAL was divided. And then, Doppler study using intraoperative transabdominal ultrasound confirmed the successful decompression of CA. This patient was discharged on postoperative day 11, and her symptoms was improved. Intraoperative assessment of blood flow in CA using transabdominal ultrasound was a simple and useful method for laparoscopic surgery of CACS.

Clinical Outcomes after Median Arcuate Ligament Release in Patients Responsive to Celiac Plexus Block.

PURPOSE: To determine if symptom relief with celiac plexus block (CPB) is associated with favorable clinical outcomes after median arcuate ligament release (MALR) surgery. MATERIALS AND METHODS: A retrospective review was performed from January 2000 to December 2021. Fifty-seven patients (42 women, 15 men; mean age, 43 years [range, 18-84 years]) with clinical and radiographic features suggestive of median arcuate ligament syndrome (MALS) underwent computed tomography (CT)-guided percutaneous CPB for suspected MALS. Clinical outcomes of CPB and MALR surgery were correlated. Adverse events were classified according to the Society of Interventional Radiology (SIR) guidelines. RESULTS: CT-guided percutaneous CPB was successfully performed in all 57 (100%) patients with suspected MALS. A cohort of 38 (67%) patients showed clinical improvement with CPB. A subset of 28 (74%) patients in this group subsequently underwent open MALR surgery; 27 (96%) responders to CPB showed favorable clinical outcomes with surgery. There was 1 (4%) CPB-related mild adverse event. There were no moderate, severe, or life-threatening adverse events. CONCLUSIONS: Patients who responded to CPB were selected to undergo surgery, and 96% of them improved after surgery.

Celiac trunk thrombosis in a patient with antiphospholipid syndrome induced by median arcuate ligament compression: a case presentation and literature review.

Median arcuate ligament syndrome (MALS) is a rare disorder caused by the compression of the celiac axis by the fibrous structure of the diaphragm called the median arcuate ligament. Patients with MALS are usually undiagnosed unless characteristic symptoms such as nausea and vomiting, postprandial pain, and weight loss are presented. We report a case of a 29-year-old patient diagnosed with MALS and secondary antiphospholipid syndrome (APS) that developed celiac trunk, common hepatic artery and splenic artery thrombosis. There is not enough information on MALS as a trigger of thrombosis in predisposed patients such as those with APS. However, the case gives rise to suspicion and highlights the diagnostic processes, especially for patients with APS presenting postprandial abdominal pain and weight loss. This review likewise aims at the importance of Doppler ultrasonography as a screening tool and computer tomography (CT) or magnetic resonance (MR) both in the angiography variant, especially to diagnose confirmation and underlying treatment options.

The anatomical relationship between the celiac artery and the median arch ligament in degenerative spinal surgery.

BACKGROUND: This study aimed to characterize the anatomical relationship between the spine, the celiac artery (CA), and the median arcuate ligament using preoperative contrast-enhanced computed tomography (CT) images of patients with spinal deformity who underwent surgical correction. METHODS: This retrospective study included 81 consecutive patients (34 males, 47 females; average age: 70.2 years). The spinal level at which the CA originated, the diameter, extent of stenosis, and calcification were determined using CT sagittal images. Patients were divided into two groups: CA stenosis group and non-stenosis group. Factors associated with stenosis were examined. RESULTS: CA stenosis was observed in 17 (21%) patients. CA stenosis group had significantly higher body mass index (24.9 ± 3.9 vs. 22.7 ± 3.7, p = 0.03). In the CA stenosis group, J-type CA (upward angling of the course by more than 90° immediately after descending) was more frequently observed (64.7% vs. 18.8%, p < 0.001). The CA stenosis group had lower pelvic tilt (18.6 ± 6.7 vs. 25.1 ± 9.9, p = 0.02) than non-stenosis group. CONCLUSIONS: High BMI, J-type, and shorter distance between CA and MAL were risk factors for CA stenosis in this study. Patients with high BMI undergoing fixation of multiple intervertebral corrective fusions at the thoracolumbar junction should undergo preoperative CT evaluation of the anatomy of CA to assess the poteitial risk of celiac artery compression syndrome.

Pancreaticoduodenal Artery Aneurysm Complicated by Median Arcuate Ligament Syndrome.

PURPOSE: To highlight median arcuate ligament syndrome as a potential cause for celiac artery stenosis and pancreaticoduodenal artery aneurysm, and describe treatment options in this setting. CASE REPORT: A 63-year-old male presented with a pancreaticoduodenal artery aneurysm and concomitant celiac artery stenosis that was treated with celiac artery stenting and aneurysm coiling. He subsequently developed stent fracture and celiac artery occlusion secondary to previously unrecognized median arcuate ligament syndrome causing reperfusion of the aneurysm. This was treated with open median arcuate ligament release and aorta to common hepatic artery bypass with good clinical result and stable 20-month surveillance imaging. CONCLUSION: It is critical to recognize median arcuate ligament syndrome as a cause of celiac artery stenosis in the setting of pancreaticoduodenal artery aneurysm given the high risk of failure of endovascular stenting. Open aorto-hepatic artery bypass and endovascular aneurysm coiling should be the preferred approach in these patients.

Obstructive jaundice as a rare complication of multiple pancreaticoduodenal artery aneurysms due to median arcuate ligament syndrome: a case report and review of the literature.

BACKGROUND: Obstructive jaundice has various causes, and one of the rarest is pancreaticoduodenal artery aneurysm (PDAA), which is often associated with celiac axis stenosis caused by median arcuate ligament syndrome (MALS). CASE PRESENTATION: The patient was a 77-year-old Azeri woman who presented with progressive jaundice, vague abdominal pain, and abdominal distension from 6 months ago. The intra- and extrahepatic bile ducts were dilated, the liver's margin was slightly irregular, and the echogenicity of the liver was mildly heterogeneous in the initial ultrasound exam. A huge cystic mass with peripheral calcification and compressive effect on the common bile duct (CBD) was also seen near the pancreatic head, which was connected to the superior mesenteric artery (SMA) and had internal turbulent blood flow on color Doppler ultrasound. According to the computed tomography angiography (CTA) findings, the huge mass of the pancreatic head was diagnosed as a true aneurysm of the pancreaticoduodenal artery caused by MALS. Two similar smaller aneurysms were also present at the huge aneurysm's superior margin. Due to impending rupture signs in the huge aneurysm, the severe compression effect of this aneurysm on CBD, and the patient's family will surgery was chosen for the patient to resect the aneurysms, but unfortunately, the patient died on the first day after the operation due to hemorrhagic shock. CONCLUSION: In unexpected obstructive jaundice due to a mass with vascular origin in the head of the pancreas, PDAA should be considered, and celiac trunk should be evaluated because the main reason for PDAA is celiac trunk stenosis or occlusion by atherosclerosis or MALS. The treatment method chosen (including transarterial embolization, open surgery, or combined method) depends on the patient's clinical status and radiological findings, but transarterial embolization would be safer and should be used as a first-line method.

Utility of Hook Sign in the Diagnosis of Median Arcuate Ligament Syndrome.

BACKGROUND: Median arcuate ligament syndrome (MALS) is a clinical syndrome caused by compression of the celiac artery by the median arcuate ligament that often manifests with nonspecific abdominal pain. Identification of this syndrome is often dependent on imaging of compression and upward bending of the celiac artery by lateral computed tomography angiography, the so-called "hook sign." The purpose of this study was to assess the relationship of radiologic characteristics of the celiac artery to clinically relevant MALS. METHODS: An institutional review board-approved retrospective chart review from 2,000 to 2,021 of 293 patients at a tertiary academic center diagnosed with celiac artery compression (CAC) was performed. Patient demographics and symptoms of 69 patients who were diagnosed with symptomatic MALS were compared to 224 patients without MALS (but with CAC) per electronic medical record review. Computed tomography angiography images were reviewed and the fold angle (FA) was measured. The presence of a hook sign (defined as a visual FA < 135°), as well as stenosis (defined as >50% of luminal narrowing on imaging) were recorded. Wilcoxon rank-sum test and Chi-squared test were used for comparative analysis. Logistic model was run to relate the presence of MALS with comorbidities and radiographic findings. RESULTS: Imaging was available in 59 patients (25 males, 34 females) and 157 patients (60 males, 97 females) with and without MALS, respectively. Patients with MALS were more likely to have a more severe FA (120.7 ± 33.6 vs. 134.8 ± 27.9, P = 0.002). Males with MALS were also more likely to have a more severe FA compared with males without MALS (111.1 ± 33.7 vs. 130.4 ± 30.4, P = 0.015). In patients with body mass index (BMI) >25, MALS patients also had narrower FA compared with patients without MALS (112.6 ± 30.5 vs. 131.7 ± 30.3, P = 0.001). The FA was negatively correlated with BMI in patients with CAC. The hook sign and stenosis were associated with diagnosis of MALS (59.3% vs. 28.7%, P < 0.001, and 75.7% vs. 45.2%, P < 0.001, respectively). In logistic regression, pain, stenosis, and a narrow FA were statistically significant predictors of the presence of MALS. CONCLUSIONS: The upward deflection of the celiac artery in patients with MALS is more severe compared with patients without MALS. Consistent with prior literature, this bending of the celiac artery is negatively correlated with BMI in patients with and without MALS. When demographic variables and comorbidities are considered, a narrow FA is a statistically significant predictor of MALS. Regardless of MALS diagnosis, a hook sign was associated with narrower FA. While demographics and imaging findings may inform MALS diagnosis, clinicians should not rely on a visual assessment of a hook sign but should quantitatively measure the anatomic bending angle of the celiac artery to assist with the diagnosis and understand the outcomes.

Outcomes of Median Arcuate Ligament Release: A Single Institution Retrospective Review.

BACKGROUND: Median arcuate ligament syndrome (MALS) is an uncommon diagnosis that is often associated with variable clinical presentation and inconsistent response to treatment. Due to the nature of MALS, the optimal treatment modality and predictors of outcomes remain unclear. METHODS: A retrospective review was performed of all median arcuate ligament release (MALR) procedures at a single academic institution between 2000 and 2020. Variables examined included patient demographics, symptom characteristics, operative technique (open, robotic, laparoscopic), patient symptoms before release, symptom relief within 1 year, and recurrence of symptoms between release and last clinical follow-up. RESULTS: During the study period, 47 patients (75% female, mean age 42.1 years) underwent MALR with 19 (36%) robotic, 18 (34%) open, 14 (26%) laparoscopic, and 2 (4%) laparoscopic converted to open procedures. Abdominal pain, weight loss, and nausea and vomiting were the most common symptoms. Postoperatively, 19 (40%) had complete symptom relief within 1 year, 18 (38%) had partial relief, and 10 (21%) had no symptom improvement. 6 were excluded due to loss of follow-up. Laparoscopic and open procedures had the highest rate of complete symptom relief by year 1 with 7 (58%) and 8 (50%) respectively. Twenty-one (57%) patients had recurrence with the greatest rate of recurrence seen among laparoscopic (80%), compared to robotic (57%) and open (38%). Patients reporting a weight loss of 20 pounds or more before surgery were more likely to have partial or complete symptom relief after 1 year compared to those reporting less than 20-pound weight loss (92% vs. 64%). Furthermore, 84% of patients younger than 60 years old reported partial or complete symptom relief compared to only 56% of those older than 60. CONCLUSIONS: MALS continues to be a rare disorder with widely variable surgical outcomes, requiring further study. While our patients presented with several gastrointestinal symptoms, the most common was postprandial pain. Our center employed laparoscopic, open, and robotic operative techniques with varying success rates, in terms of symptom relief and recurrence. Consistent with current literature, our study found greater surgical success among patients younger than 60 years regardless of operative technique. This suggests the need for better predictors to determine which patients are the most likely to have complete or prolonged remission of symptoms following MALR.

Median arcuate ligament syndrome: a rare cause of abdominal pain.

MALS, also called celiac artery compression syndrome, celiac axis syndrome, or Dunbar syndrome, is a rare entity caused by progressive stenosis of the celiac trunk secondary to extrinsic compression of the fibers of the median arcuate ligament. The prevalence is unknown, but it is estimated that it is a casual finding in up to a third of autopsies2,3, being more prevalent in women between 30 and 50 years of age4. Symptoms and signs include postprandial abdominal pain, exercise-induced pain, nausea, vomiting, and weight loss3. However, most cases are asymptomatic. The case that we present was a 56-year-old man, with a history of dyslipidemia, type 2 diabetes mellitus, and chronic ischemic heart disease. He was a former smoker. He reported a history of recurrent abdominal pain, especially postprandial.

Factors associated with successful median arcuate ligament release in an international, multi-institutional cohort.

OBJECTIVE: Prior research on median arcuate ligament syndrome has been limited to institutional case series, making the optimal approach to median arcuate ligament release (MALR) and resulting outcomes unclear. In the present study, we compared the outcomes of different approaches to MALR and determined the predictors of long-term treatment failure. METHODS: The Vascular Low Frequency Disease Consortium is an international, multi-institutional research consortium. Data on open, laparoscopic, and robotic MALR performed from 2000 to 2020 were gathered. The primary outcome was treatment failure, defined as no improvement in median arcuate ligament syndrome symptoms after MALR or symptom recurrence between MALR and the last clinical follow-up. RESULTS: For 516 patients treated at 24 institutions, open, laparoscopic, and robotic MALR had been performed in 227 (44.0%), 235 (45.5%), and 54 (10.5%) patients, respectively. Perioperative complications (ileus, cardiac, and wound complications; readmissions; unplanned procedures) occurred in 19.2% (open, 30.0%; laparoscopic, 8.9%; robotic, 18.5%; P < .001). The median follow-up was 1.59 years (interquartile range, 0.38-4.35 years). For the 488 patients with follow-up data available, 287 (58.8%) had had full relief, 119 (24.4%) had had partial relief, and 82 (16.8%) had derived no benefit from MALR. The 1- and 3-year freedom from treatment failure for the overall cohort was 63.8% (95% confidence interval [CI], 59.0%-68.3%) and 51.9% (95% CI, 46.1%-57.3%), respectively. The factors associated with an increased hazard of treatment failure on multivariable analysis included robotic MALR (hazard ratio [HR], 1.73; 95% CI, 1.16-2.59; P = .007), a history of gastroparesis (HR, 1.83; 95% CI, 1.09-3.09; P = .023), abdominal cancer (HR, 10.3; 95% CI, 3.06-34.6; P < .001), dysphagia and/or odynophagia (HR, 2.44; 95% CI, 1.27-4.69; P = .008), no relief from a celiac plexus block (HR, 2.18; 95% CI, 1.00-4.72; P = .049), and an increasing number of preoperative pain locations (HR, 1.12 per location; 95% CI, 1.00-1.25; P = .042). The factors associated with a lower hazard included increasing age (HR, 0.99 per increasing year; 95% CI, 0.98-1.0; P = .012) and an increasing number of preoperative diagnostic gastrointestinal studies (HR, 0.84 per study; 95% CI, 0.74-0.96; P = .012) Open and laparoscopic MALR resulted in similar long-term freedom from treatment failure. No radiographic parameters were associated with differences in treatment failure. CONCLUSIONS: No difference was found in long-term failure after open vs laparoscopic MALR; however, open release was associated with higher perioperative morbidity. These results support the use of a preoperative celiac plexus block to aid in patient selection. Operative candidates for MALR should be counseled regarding the factors associated with treatment failure and the relatively high overall rate of treatment failure.