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

Laparoscopic median arcuate ligament release using an anterior approach for median arcuate ligament syndrome

Median arcuate ligament syndrome (MALS) is a rare condition characterized by nonspecific symptoms, such as abdominal pain, nausea, and vomiting. Furthermore, the development and rupture of pancreaticoduodenal artery aneurysms pose a potentially fatal risk. Median arcuate ligament release (MALR) is useful in the treatment of MALS, with most procedures performed laparoscopically. However, detailed descriptions of laparoscopic MALR (lap-MALR) procedures are rare. In this study, we performed lap-MALR via an anterior approach with dissection of the right lateral wall of the celiac artery (CA). For optimal visualization of the right side of the CA, the right branch of the inferior phrenic artery was divided. We believe that this procedure allows the MAL to be released within a sufficient surgical field and without excess or deficiency. Here, we present the details of six patients who underwent lap-MALR for varying indications; three for pancreaticoduodenal artery aneurysms due to CA obstruction (unruptured, n = 1; ruptured, n = 2), two cases prior to hepato-biliary-pancreatic surgery, and one symptomatic case. In all cases, lap-MALR was performed as described above, and the CA stenosis was successfully released. Our case series demonstrates the safety and reliability of our lap-MALR procedure in the treatment of MALS-related disorders, including pancreaticoduodenal artery aneurysms associated with CA compression.

Median Arcuate Ligament Syndrome: Where Are We Today?

Median arcuate ligament syndrome, or celiac artery compression syndrome (eponym: Dunbar syndrome), has historically been attributed to pathophysiologic vascular compression causing downstream ischemic symptoms of the organs supplied by the celiac trunk. However, the more we learn about the histology, clinical presentation, and treatment outcomes, health care providers are increasingly correlating the symptoms of MALS with the long-term, repetitive compression of the celiac ganglion rather than the celiac trunk. This article provides a comprehensive review of current MALS literature, emphasizing the multidisciplinary approach these patients require in all phases of their care. With most patients with MALS waiting an average of 10.5 months to 2.6 years, 9, 10 our need for better diagnostic protocols and clearer understanding of the pathophysiology of the disease is paramount. Further investigation into patient outcomes, associated conditions, and linked pathophysiology would help better characterize this disease with hopes of moving it from a diagnosis of exclusion to one of standard work-up with decreased time to treatment and symptom relief for patients.

Institutionalized Adoption of a Protocol for the Management of Median Arcuate Ligament Syndrome Correlates with Improved Surgical Outcomes

BACKGROUND

Median arcuate ligament syndrome (MALS) is a rarely diagnosed and treated etiology of abdominal pain with no established diagnostic approach. The effectiveness of our institutional protocol in identifying these patients was investigated by analyzing their surgical outcomes.

METHODS

A retrospective review was conducted of patients treated for MALS at our institution from 2001 to 2022. Patients were considered for a diagnosis of MALS if there was evidence of abdominal pain (unprovoked, provoked by eating, and physical activity) and celiac artery dynamic compression on diagnostic imaging. During the study period, an institutionalized management protocol was developed for these patients. Patients were then categorized as having positive surgical outcomes if their symptoms improved or resolved entirely during the latest follow-up visit, while those whose symptoms remained unchanged or worsened were classified as having negative outcomes. Of the patients considered for MALS diagnosis, a patient was confirmed positive if there is either a positive provocative mesenteric angiogram, celiac plexus block, or both, along with a negative gastroenterology workup. Comparative analysis was performed using a chi-square test. Multivariable logistic regression models were performed to evaluate the association between risk factors and symptom relief with the adjusted follow-up length. All tests were 2-sided, with P value <0.05 considered statistically significant.

RESULTS

A total of 163 patients with a mean follow-up duration of 17.7 + 23.4 months were included in the study. Patients who were part of the protocol had a higher rate of improvement in their abdominal pain (65.9% vs. 50.0%, P < 0.04). Furthermore, patients diagnosed positive by the protocol experienced greater relief of abdominal pain compared to patients with a negative diagnosis (77.8% vs. 52.5%, P = 0.014).

CONCLUSIONS

By using a standardized protocol, patients who received a positive diagnosis demonstrated symptomatic improvement in their outcomes. Further investigation is warranted on a larger scale to assess its generalizability for the management of this challenging patient population.

Robotic median arcuate ligament release: a video vignette

Median arcuate ligament syndrome (MALS) poses a rare challenge in diagnosis and management. We present a case of MALS in a 50-year-old male with recurrent epigastric pain, vomiting, and diarrhea. Diagnostic imaging revealed celiac artery stenosis and gastroduodenal artery collateral dilatation. Robotic-assisted median arcuate ligament release successfully alleviated symptoms. Utilizing the da Vinci X system (Intuitive Surgical, Inc.), the procedure involved meticulous dissection of the celiac artery and surrounding tissue. Postoperative duplex ultrasound confirmed improved arterial flow. Literature underscores the diagnostic hurdles of MALS and the advantages of minimally invasive approaches over conventional open surgery. The robotic approach may help smoothen the learning curve associated with this procedure, by providing improved operative flexibility. Patient outcomes are excellent, with long-term symptom relief in most cases.

Feasibility and safety of robotic-assisted surgical approach in median arcuate ligament syndrome-a systematic review

Median arcuate ligament syndrome (MALS) is rare syndrome and is diagnosis of exclusion. Though first robotic median arcuate ligament release (MALR) was described in 2007, there are only a few case reports (CR), case series (CS), and retrospective cohort studies (RCS) in the published literature. The purpose of this study was to assess the feasibility and safety of robotic-assisted MALR (r-MALR). PubMed, Embase, and Cochrane databases were searched (last search December 2023) for articles reporting r-MALR. All studies including CR, CS, RCS reporting technical feasibility (operating time and rate of conversions), safety (intra-operative complications, blood loss, post-operative complications), and outcome (length of stay [LoS]) were included (PROSPERO: CRD42024502792). A total of 23 studies (8-CR, 5-CS, 10-RCS) with total 290 patients were available in the literature. Except 1-RCS, all studies reported age and mean age for CR was 40.38 ± 17.7, 36.08 ± 15.12 for CS, 39.72 ± 7.35 years for RS; except 2-RCS, all studies reported gender distribution and there were 57 males and 214 females. Operating time: 3-CR, 4-CS, 9-RCS reported operating time, and mean time was 111 ± 54, 131.69 ± 7.51, 117.34 ± 35.03 min, respectively. Conversion rate: All studies reported data on conversion and only four (1.37%) cases were converted-one to laparoscopic approach, three to open approach (1-inadvertent celiac arteriotomy, 2-reasons not mentioned). Intraoperative complications: only 5-CR, 4-CS, and 9-RCS reported data on intra-operative complications, and there were only 6 complications (1.5%): 1-inadvertent celiac arteriotomy converted to open; 3-unnamed vascular injuries (2 managed robotically, 1 converted to open); 1-bleeding managed robotically; there were no other reported injuries. Estimated blood loss ranged from 5 to 30 ml. Post-operative complications: 5-CR, 4-CS, 8-RCS described post-operative complications in 21 (7%) patients. Twenty cases were grade I, one was grade IIIa, and all managed successfully. LoS stay: 2-CR, 4-CS, 10-RCS reported LoS and overall, it was 2 days. r-MALR is reasonable, technically feasible, safe, and has acceptable outcomes. In addition, robotic approach provided superior vision, improved dexterity, precise, and easy circumferential dissection.PROSPERO registration: The protocol was registered in the PROSPERO database (CRD42024502792).

Median arcuate ligament release at the time of pancreaticoduodenectomy or total pancreatectomy

BACKGROUND

Celiac artery compression can complicate the performance of pancreaticoduodenectomy or total pancreatectomy due to the need for ligation of the gastroduodenal artery. Median arcuate ligament release restores normal arterial flow to the liver, spleen, and stomach and may avoid complications related to poor perfusion of the foregut.

METHODS

All patients who underwent median arcuate ligament release for celiac artery compression at the time of pancreatectomy between 2009 and 2023 were reviewed. Pre- and postoperative computed tomography was used to categorize celiac artery compression by the extent of compression (types A [<50%], B [50%-80%], and C [>80%]).

RESULTS

Of 695 patients who underwent pancreatectomy, 22 (3%) had celiac artery compression, and a majority (17) were identified on preoperative imaging. Median celiac artery compression was 52% (interquartile range = 18); 8 (36%) patients had type A and 14 (64%) had type B compression with a median celiac artery compression of 39% (interquartile range = 18) and 59% (interquartile range = 14), respectively (P < .001). Postoperative imaging was available for 20 (90%) patients, and a reduction in the median celiac artery compression occurred in all patients: type A, 14%, and type B, 31%. Complications included 1 (5%) death after hospital discharge, 1 (5%) pancreatic fistula, 1 (5%) delayed gastric emptying, and 4 (18%) readmissions. No patient had evidence of a biliary leak or liver dysfunction.

CONCLUSION

Preoperative computed tomography allows accurate identification of celiac artery compression. Ligation of the gastroduodenal artery during pancreaticoduodenectomy or total pancreatectomy in the setting of celiac artery compression requires median arcuate ligament release to restore normal arterial flow to the foregut and avoid preventable complications.

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.

First description of a histopathologic grading system and relationship to outcomes after robotic median arcuate ligament release with celiac ganglionectomy and lymphadenectomy

BACKGROUND

Two dominating theories regarding median arcuate ligament syndrome include vascular and neurogenic etiologies from celiac artery and ganglion compression, respectively. Celiac ganglionectomy is not routine during surgery, and specimens are rarely excised; therefore, the extent of nerve involvement and histopathology are unknown. Our study aims to characterize histopathologic findings in median arcuate ligament syndrome, establish a histopathologic grading system, and correlate with clinical outcomes.

METHODS

Robotic median arcuate ligament release, celiac ganglionectomy, and lymphadenectomy were performed with specimens excised and stained using hematoxylin & eosin, trichrome, and S100. Neurofibrosis, adiposity, and reactive changes were described, a grading scale was developed, and results were analyzed with clinical outcomes.

RESULTS

Fifty-four patients were evaluated, of whom 36 met inclusion criteria (81% female, 34.9 [25.9-47.5] years, body mass index 23.5 [19.6-28.1] kg/m2). Histopathologic evaluation revealed fibrosis (hematoxylin & eosin and trichrome median score 1.5 [0-2.5]), reactive lymphadenopathy (89%), intraparenchymal nerves (31%), and lipogranulomas (31%). Greater fibrosis was associated with a lack of preoperative celiac plexus block relief (100% vs. 30%, P = .044) and lower postoperative celiac artery velocities (198 vs 323 cm/s, P = .02). Intraparenchymal nerves were associated with greater decreases in pre to postoperative velocities (161 vs 84 cm/s, P = .037). Symptoms improved in 28 patients (78%).

CONCLUSION

We developed the first histopathologic grading system and identified unique findings of intraparenchymal nerves and lipogranulomas. Histopathologic abnormalities were associated with objective improvement and symptomatic relief postoperatively. These findings support nerve compression and inflammation as predominant contributors to median arcuate ligament syndrome pain, celiac ganglia resection to treat symptoms, and continued histopathologic analysis to better elucidate median arcuate ligament syndrome etiology.

Median arcuate ligament syndrome: a cost analysis to determine the economic burden of a rarely diagnosed disease

Background

Chronic abdominal pain (CAP) is a medical condition resulting in enormous economic burden and healthcare utilization costs. One understudied source of CAP is the median arcuate ligament syndrome (MALS). MALS is often not diagnosed and treated for a variety of reasons, including the fact that MALS is highly comorbid with psychological symptoms and psychiatric disorders similar to CAP. To better inform future work on the study of MALS, we undertook a pilot study to estimate the economic impact and public health burden of this condition. We hypothesized that MALS imposes a significant public health burden.

Methods

Pediatric and adult patients enrolled in a prospective study undergoing multidisciplinary evaluation and treatment for MALS at a tertiary care facility were invited to participate in a brief self-report survey, the Direct and Indirect Medical Care Impact of MALS Form, to capture health care resources including procedures, surgeries, health care visits, and absenteeism (school and work). To estimate costs from the Direct and Indirect Medical Care Impact of MALS Form, the medical care usage data self-reported by patients were converted to dollar value utilizing FSC-93 billing data and corresponding current procedural terminology (CPT) codes for procedures and provider visits one year prior to surgery and then following surgery. Descriptive analyses were conducted to characterize the sample in terms of demographics and reported absences from school and work.

Results

One hundred and nineteen patients (mean age = 30.9 ± 13.0) completed the questionnaires, yielding a 57% response rate. 82.4% (n = 98) of the participants were female and 90.8% (n = 108) were non-Hispanic/Latine white. The mean and median surgical follow-up periods were 5.3 and 5.4 years, respectively. Overall, median cost of provider and ancillary healthcare provider visits for each patient was (US)$19,119 including the pre-operative and post-operative visits. The mean cost for providers alone was (US)$28,908. Wilcoxon signed-ranks tests indicated that the postoperative missed number of days of school were significantly lower than the pre-surgical number of missed school days (Z = -3.36, p = 0.001). Similarly, there were significantly less missed work-days following surgery than before for the entire sample (Z = -2.86, p = 0.004).

Conclusion

Median arcuate ligament syndrome imposes a large economic burden on patients and the healthcare system. The current findings, although reflective of a homogenous population, are adding to a growing body of literature suggesting that healthcare disparities play a role in the low rates of diagnosis and treatment of MALS.

Prevalence and outcomes of select rare vascular conditions in females: A descriptive review

Rare vascular conditions frequently pose a diagnostic and therapeutic dilemma for health care providers. Several of these conditions have distinct relevance to females populations but, due to their infrequency, there has been little reported on the outcomes of rare vascular conditions specifically in females populations. We performed a literature review of a selection of three rare vascular conditions known to either disproportionately affect females (median arcuate ligament syndrome and fibromuscular dysplasia) or have unique manifestations in females populations (vascular Ehlers-Danlos syndrome). We performed a descriptive review of the literature focused on these three vascular conditions and identified aspects of the current available research describing sex-based differences in prevalence, any pathophysiology explaining the observed sex-based differences, and the contribution of sex to outcomes for each disease process. In addition, considerations for pregnant females with respect to each rare vascular disease process are discussed.

Overview of Median Arcuate Ligament Syndrome: A Narrative Review

Median arcuate ligament syndrome (MALS) is a rare disorder caused primarily by compression of the celiac trunk by the median arcuate ligament (MAL). This disorder typically results in patients presenting with bloating, weight loss, nausea, vomiting, and abdominal pain. The MALS diagnosis is one of exclusion, as the disorder has no specific diagnostic criteria. Imaging modalities are often utilized to assist in making the diagnosis, such as ultrasound, computed tomography angiography (CTA), and magnetic resonance angiography (MRA). These imaging modalities typically reveal a stenosed celiac artery with post-stenotic dilation in patients. This disorder is usually treated by dividing the MAL, thus relieving the compression of the celiac artery. The surgery may be done through either an open approach or a minimally invasive approach, which can be either laparoscopic or robot-assisted. Most patients respond well to this treatment, though certain factors that predict a poorer response to treatment include elderly age, a history of alcohol abuse, and psychiatric illness.

Median arcuate ligament syndrome often poses a diagnostic challenge: A literature review with a scope of our own experience

The median arcuate ligament syndrome (MALS) is recognized as a rare clinical entity, characterized by chronic post-prandial abdominal pain, nausea, vomiting, and unintentional weight loss. Due to its vague symptomatology, it is mainly regarded as a diagnosis of exclusion. Patients can often be misdiagnosed for several years before a correct diagnosis is established, also due to a medical team’s clinical suspicion. We present a case series of two patients who suffered from MALS and were treated successfully. The first patient is a 32-year-old woman, presenting with post-prandial abdominal pain and weight loss that have lasted for the past ten years. The second patient, a 50-year-old woman, presented with similar symptomatology, with the symptoms lasting for the last five years. Both cases were treated by laparoscopic division of the median arcuate ligament fibers, which alleviated extrinsic pressure from the celiac artery. Previous cases of MALS were retrieved from PubMed, to assemble a better diagnostic algorithm and propose a treatment method of choice. The literature review suggests an angiography with a respiratory variation protocol as the diagnostic modality of choice, along with the laparoscopic division of the median arcuate ligament fibers as the proposed treatment of choice.

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

OBJECTIVE

Median arcuate ligament syndrome (MALS) is a clinical syndrome caused by compression of the celiac artery by the median arcuate ligament (MAL) that often manifests with non-specific abdominal pain. Identification of this syndrome is often dependent on imaging of compression and upward bending of the celiac artery by lateral CTA, the so-called "hook sign." The purpose of this study was to assess the relationship of radiologic characteristicss of the celiac artery to clinically relevant MALS.

DESIGN

Single-center retrospective study METHODS: An IRB-approved retrospective chart review from 2000-2021 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. CTA images were reviewed and the fold angle (FA) was measured. The presence of a hook sign (defined as a visual fold angle < 135 degrees) was recorded as well as stenosis (defined as >50% of luminal narrowing on imaging). Wilcoxon rank sum test and Chi-squared were utilized 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 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.