Diagnosis and Management of Isolated Superior Mesenteric Artery Dissection: A Systematic Review and Meta-Analysis

A case of isolated SMA dissection with failed initial conservative management

Isolated superior mesenteric dissection (ISMAD) is an uncommon condition, often diagnosed incidentally for presentations of acute abdominal pain. Early identification and treatment are crucial as complications such as bowel ischemia or vessel rupture can occur. There remain no established treatment guidelines, making surgical and endovascular indications controversial. A 60-year-old male presented with acute abdominal pain, and was diagnosed with ISMAD via computed tomography imaging. He was initially managed conservatively which progressed to worsening abdominal pain, hypertensive crisis, and hemoperitoneum on follow-up computed tomography angiography (CTA). A mesenteric angiogram revealed a pseudoaneurysm in the superior mesenteric artery (SMA) which was subsequently treated with coil embolization. The absence of long-term evidence on relapse rates questions the overall effectiveness of nonoperative therapy. Further research is needed to establish clear guidelines and to determine whether early intervention might be more advantageous in managing complications and preventing recurrence.

The value evaluation of Nomogram prediction model based on CTA imaging features for selecting treatment methods for isolated superior mesenteric artery dissection

OBJECTIVE

To evaluate value of Nomogram prediction model based on CTA imaging features for selecting treatment methods for isolated superior mesenteric artery dissection (ISMAD).

METHODS

Symptomatic ISMAD patients were randomly divided into a training set and a validation set in a 7:3 ratio. In the training set, relevant risk factors for conservative treatment failure in ISMAD patients were analyzed, and a Nomogram prediction model for treatment outcome of ISMAD was constructed with risk factors. The predictive value of the model was evaluated.

RESULTS

Low true lumen residual ratio (TLRR), long dissection length, and large arterial angle (superior mesenteric artery [SMA]/abdominal aorta [AA]) were identified as independent high-risk factors for conservative treatment failure (P < 0.05). The receiver operating characteristic curve (ROC) results showed that the area under curve (AUC) of Nomogram prediction model was 0.826 (95% CI: 0.740-0.912), indicating good discrimination. The Hosmer-Lemeshow goodness-of-fit test showed good consistency between the predicted curve and the ideal curve of the Nomogram prediction model. The decision curve analysis (DCA) analysis results showed that when probability threshold for the occurrence of conservative treatment failure predicted was 0.05-0.98, patients could obtain more net benefits. Similar results were obtained for the predictive value in the validation set.

CONCLUSION

Low TLRR, long dissection length, and large arterial angle (SMA/AA) are independent high-risk factors for conservative treatment failure in ISMAD. The Nomogram model constructed with independent high-risk factors has good clinical effectiveness in predicting the failure.

Spontaneous isolated superior mesenteric artery dissection: an investigative case report

Spontaneous isolated superior mesenteric artery dissection (SISMAD) is a rare cause of acute abdominal pain, but could potentially be fatal to patients, and should be recognized soon in the emergency department after excluding other common causes. Computed tomography (CT) is the modality of choice for initial diagnosis and follow-up. Currently there is no evidence-based guidelines for managing SISMAD. A 58-year-old man being suspected of a mesenteric artery dissection was referred to our emergergy department. The patient was monitored, treated conservatively with anticoagulant and discharged after 3 days. Follow-up CT scans at 6 month, 1 year and 1 year and a half post discharge showed a partially occluded false lumen, the diameter of true lumen had increased in size and no signs of bowel ischemia. SISMAD should be considered as part of differential diagnoses when patients in their fifth to seventh decades of life present with acute abdominal pain. Treatment includes conservative management, percutaneous endovascular interventions, or surgery, but most patients can be managed conservatively.

Comparison of clinical outcomes between medical or/and endovascular therapy in spontaneous isolated superior mesenteric artery dissection patients without bowel ischemia

OBJECTIVE

This study aims to assess the clinical results of endovascular intervention for spontaneous isolated superior mesenteric artery dissection (SISMAD) and its impact on superior mesenteric artery (SMA) remodeling in comparison to solely medical management.

METHODS

All patients with SISMAD between January 2015 and August 2023 were included. The primary endpoints were the absence of major adverse events (MAEs), including dissection-related mortality, recurrence of mesenteric ischemia symptoms, and the necessity for intervention. The secondary endpoints were stenosis or occlusion of the SMA and morphologic remodeling of the dissections.

RESULTS

A total of 217 SISMAD patients were included. In this study, 127 (58.5 %) patients received medical management alone (conservative group), and 90 (41.5 %) underwent endovascular therapy (EVT group). In the EVT group, the technical success rate was 94.4 % (85/90). During follow-up, 13 (6.0 %) patients experienced MAEs, and 1 patient in the conservative group death related to SISMAD. The patients in EVT group showed more complete remodeling than those in the conservative group (76 (84.4 %) vs 66 (52.0 %), P < .0001). Survival analysis showed that the estimated MAEs-free survival rates were97.8 %, 95.6 %, and 95.6 % in EVT group and 98.4 %, 94.5 %, 92.9 % in conservative group at one, two, and three years, respectively. No significant difference was observed in both groups.

CONCLUSION

The findings indicate that both endovascular treatment and medical management alone yield comparable rates of MAE-free survival among patients with SISMAD. Additionally, endovascular therapy exhibits a higher rate of complete remodeling and greater freedom from stenosis or occlusion of the SMA.

Open thrombectomy, patch angioplasty, and retrograde stenting for isolated superior mesenteric artery dissection

Isolated superior mesenteric artery dissection without aortic involvement is an exceptionally rare event. Nonoperative management remains the first-line therapy. However, surgical interventions can be indicated in the event of bowel ischemia. In the present report, we describe a case of complicated isolated superior mesenteric artery dissection treated with a hybrid approach.

Secondary Hemorrhagic Shock Due to Spontaneous Isolated Dissection of the Superior Mesenteric Artery Branch

Spontaneous isolated dissection of the superior mesenteric artery (SIDSMA) is a rare condition, particularly when complicated by hemorrhagic shock. This case report describes the discovery of SIDSMA in an 88-year-old woman through CT angiography. The patient initially presented with acute abdominal pain, nausea, and diarrhea, which later progressed to hemorrhagic shock. After fluid resuscitation, the patient underwent successful endovascular treatment.

A Case of Isolated Superior Mesenteric Artery Dissection Resulting in Recurrent Necrosis of the Small Intestine

Isolated superior mesenteric artery dissection (ISMAD) is a rare cause of acute abdominal conditions. Most cases of ISMAD have a favorable prognosis, and only a few cases of ISMAD-associated intestinal necrosis have been reported. A 75-year-old male was referred to our department because of abdominal pain and portal venous gas detected on imaging. Computed tomography suggested ileal necrosis, necessitating emergency surgery. Indocyanine green was used for blood flow assessment; however, no fluorescence was observed in the ileum proximal to the Bauhin valve, leading to the decision for ileocecal resection. On postoperative day 6, abdominal pain recurred when meals were resumed. As a surgical intervention for ISMAD, a bypass was created using the left great saphenous vein as a graft between the superior mesenteric artery and the right external iliac artery. This case highlights a rare occurrence where intestinal necrosis recurred due to ISMAD. We propose that in cases of ISMAD with concomitant intestinal necrosis, a more aggressive revascularization strategy for the dissected segment of the superior mesenteric artery may be required.

Spontaneous isolated superior mesenteric artery dissection: A case report and brief analysis

This case report describes the clinical presentation, diagnostic approach, and treatment strategies for a 58-year-old male patient diagnosed with spontaneous isolated superior mesenteric artery dissection (SISMAD). The patient presented with suddenonset abdominal pain and was diagnosed with SISMAD using computed tomography angiography (CTA). SISMAD is a rare but potentially serious condition that can lead to bowel ischemia and other complications. Management options include surgery, endovascular therapy and conservative management with anticoagulation and close observation. The patient was managed conservatively with antiplatelet therapy and close follow-up. During hospitalization, he received antiplatelet therapy and was closely monitored for signs of bowel ischemia or other complications. The patients' symptoms gradually improved over time, and he was eventually discharged on oral mono- antiagreggation therapy. Clinical follow-up showed a significant symptimatic improvement. Conservative management with antiplatelet therapy was chosen due to the absence of bowel ischemia signs and overall stable clinical condition of patient. This report emphasizes the importance of prompt recognition and management of SISMAD to prevent potentially life-threatening complications. Conservative management with antiplatelet therapy can be a safe and effective treatment option for SISMAD, especially in cases without evidence of bowel ischemia or other complications.

Worsening Isolated Superior Mesenteric Artery Dissection on the Day After Discharge

A 59-year-old male was transported to the emergency department by ambulance with complaints of left-sided abdominal pain. Blood gas analysis revealed elevated lactate, and plain computed tomography revealed no bowel ischemic change. Contrast-enhanced computed tomography revealed isolated superior mesenteric artery dissection with mildly stenosed true lumen. The patient was treated with conservative management on admission. Staged fluid intake, oral prescriptions, and diet were commenced with attention to the symptoms. After four days of hospitalization, the patient was discharged with a stable condition. However, the patient returned to our hospital complaining of left lower back pain three hours after discharge. Contrast-enhanced computed tomography revealed an enlarged false lumen with a moderately stenosed true lumen. After a thorough discussion between vascular surgeons and interventional radiologists, conservative management was commenced on the second admission. The clinical course was uneventful, with proof of improved imaging findings.

Conservative Treatment for Isolated Superior Mesenteric Artery Dissection With Severely Narrowed True Lumen

A 59-year-old male presented to the emergency department with distressing epigastric pain after seeking medical attention at a nearby clinic three hours prior. Upon examination, the attending physician noticed edematous changes in the proximal segment of the superior mesenteric artery, and a subsequent enhanced computed tomography (CT) scan confirmed the diagnosis of an isolated dissection of the artery. Notably, the true lumen of the vessel was significantly narrowed, raising concerns for potential vascular compromise. After extensive consultation between a vascular surgeon and a radiologist, a decision was made to adopt a conservative management approach. The patient was closely monitored with meticulous bowel rest, hydration management, and carefully curated dietary modifications. Over time, subsequent CT scans revealed progressive enlargement of the true lumen, which was highly reassuring to the medical team. As a result of the expert management and diligent care provided, the patient was eventually discharged home without any adverse events or complications. This case highlights the critical role of a multidisciplinary approach in managing complex vascular pathology and underscores the importance of thoughtful clinical decision-making and meticulous monitoring in achieving favorable outcomes.

Analysis of safety and efficacy of conservative treatment and endovascular treatment in patients with spontaneous isolated mesenteric artery dissection

Background

Spontaneous isolated superior mesenteric artery dissection (SISMAD) is a rare disease with abdominal pain as the main clinical manifestation, but its optimal treatment strategy has not yet been determined. Based on this, this study explored a safe and effective treatment method by analyzing and comparing the safety and efficacy of conservative treatment and endovascular treatment in SISMAD patients.

Methods

The clinical and imaging data and treatment effects of 85 patients with SISMAD who were admitted to the General Surgery Department of the 900th Hospital of the Joint Logistics Support Force of the Chinese People's Liberation Army from January 2008 to December 2020 were retrospectively analyzed. Two groups were treated, the data of patients in conservative treatment group and endovascular treatment group were analyzed, and a safe and effective treatment method for SISMAD was discussed.

Results

The mean follow-up time was 36.58 ± 25.03 months. The success rate of interventional operation was 86.11% (31/36), and the operation failed because the guide wire could not enter the true lumen in four cases. One case was terminated due to poor physical condition of the patient who could not tolerate surgery. There were no significant differences in gender, body mass index, clinical manifestations, and past history between conservative treatment and endovascular treatment (P > 0.05), but in age, superior mesenteric artery-distal aorta angle, distance from the superior mesenteric artery opening to dissection, dissection length, and true lumen stenosis. There was a statistical difference between the two groups in the rate and Yun classification (P < 0.05).

Conclusions

Conservative treatment is effective for most symptomatic SISMAD patients, and close monitoring is required; for patients with persistent symptoms and severe true lumen stenosis (especially Yun classification type III), endovascular treatment is preferred; endovascular treatment is mainly based on endovascular bare stent placement. Patients receiving stent implantation may suffer from stent stenosis or occlusion in the long term, and most of them have no obvious symptoms of intestinal ischemia; the prognosis is good.

Correlation of Riolan's arch diameter to treatment choice in patients with isolated superior mesenteric artery dissection

OBJECTIVE

To investigate the diameter changes of Riolan's arch in patients with isolated superior mesenteric artery dissection (ISMAD) and to evaluate the implication for treatment selection.

METHODS

Ninety-five patients with CT angiography (CTA) confirmed ISMAD were retrospectively included, and another 95 cases with no positive findings on abdominal CTA were included as controls. According to the treatment methods, the patients were subsequently divided into conservative treatment (n = 68) or invasive treatment (n = 27) subgroups. According to the initial CTA images, the prevalence of Riolan's arch as well as its diameter (D_R) were determined in each subject, and compared between ISMAD and control cases, as well as between patients with different treatments. In patients with ISMAD, dissections were classified according to the Li classification.

RESULTS

Riolan's arch prevalence and D_R were significantly elevated in the ISMAD group compared with the control group (83.16% vs. 35.79%, P < 0.001; 2.63 ± 0.56 mm vs. 2.12 ± 0.39 mm, P < 0.001). Patients with invasive treatment had significantly higher baseline D_R (2.93 ± 0.57 mm vs. 1.89 ± 1.14 mm, P < 0.001), and higher proportion of high-risk dissection (P < 0.001) than those administered conservative treatment. Binary logistic regression revealed D_R (OR = 2.771, 95% CI 1.157-6.638, P = 0.022) and Li classification (OR = 0.107, 95% CI 0.019-0.586, P = 0.010) were independent risk factors for treatment selection. With cutoff of 2.635 mm, the area under the curve, sensitivity, and specificity were 0.805, 0.778 and 0.794, respectively.

CONCLUSION

Dilation of Riolan's arch is common in patients with ISMAD, and Riolan's arch diameter could be a convenient indicator of disease severity and inform subsequent treatment.

Isolated Superior Mesenteric Artery Dissection: An Unusual Etiology of Epigastric Pain

Abdominal pain is a very common presentation in the emergency department (ED). The pain is often well-characterized and leads to the diagnosis, but often, the presentation is vague and nonspecific. Superior mesenteric artery (SMA) dissection is a rare cause of abdominal pain that presents with nonspecific epigastric pain and is common in males, middle age, and patients of Asian descent. A high index of suspicion is usually helpful with imaging modalities such as computer tomography (CT) scan and ultrasonography in experienced hands. A prompt diagnosis is vital to managing this disease which may range from non-surgical intervention with supportive therapy to invasive endovascular procedures and surgery. Here, we report a case of an isolated SMA dissection presenting with vague abdominal symptoms and highlight the need to explore the vascular etiology of abdominal pain as their diagnosis is often difficult and may result in irreversible bowel injury when missed.

Clinical characteristics and misdiagnosis of spontaneous isolated superior mesenteric artery dissection

Background

Spontaneous isolated superior mesenteric artery (SMA) dissection (SISMAD) is a rare disease with a potentially fatal pathology. Due to the lack of specificity of clinical characteristics and laboratory tests, misdiagnosis and missed diagnosis are often reported. Therefore, the aim of this study was to investigate the clinical characteristics and misdiagnosis of SISMAD.

Methods

In a registry study from January 2013 to December 2020, 110 patients with SISMAD admitted to the First Affiliated Hospital of Wenzhou Medical University were enrolled. Descriptive methods were used to analyse clinical characteristics, laboratory data, diagnostic method or proof, misdiagnosed cases, plain computed tomography (CT) findings and dissection features. To study the relationship between dissection features and treatment modality, the selected patients were classified into the conservative group (n = 71) and the non-conservative group (n = 39). The Chi-square test and Student’s t-test were used to compare the conservative and non-conservative groups.

Results

One hundred ten patients with SISMAD, including 100 (90.9%) males and 10 (9.1%) females, with a mean age of 52.4 ± 7.6 years, were enrolled in the study. Relevant associated comorbidities included a history of hypertension in 43 cases (39.1%), smoking in 46 cases (41.8%), and alcohol consumption in 34 cases (30.9%). One hundred four patients (94.5%) presented with abdominal pain. Abnormalities in the C-reactive protein lever, white blood cells count and D-dimer lever were the 3 most common abnormal findings. There were 32 misdiagnosis or missed diagnosis. Fourteen cases were misdiagnosed because of insufficient awareness. Twelve cases were misdiagnosed because of disease features. Twenty cases were misdiagnosed as SMA embolism. Among them, There were 15 cases of Yun type IIb SISMAD. Sixty-six patients underwent plain CT. The maximum SMA diameter was 12.1 (11.3–13.1) mm, and the maximum SMA diameter was located on the left renal vein (LRV) plane in 68.2% of cases. Dissection features observed on contrast-enhanced CT (CECT), CT angiography (CTA), or digital subtraction angiography (DSA) showed that there were 70 cases (63.6%) of Yun type IIb SISMAD, the maximum SMA diameter was 13.0 ± 2.4 mm, the location of the maximum SMA diameter was on the LRV plane in 64.5% of cases, and 7.3% of cases were complicated with intestinal obstruction, including bowel necrosis in 3.6% of cases. There were differences between the conservative group and non-conservative groups in the residual true lumen diameter or degree of true lumen stenosis and the presence of intestinal obstruction or bowel necrosis (all P < 0.05).

Conclusion

For SISMAD, misdiagnosis and missed diagnosis were usually caused by insufficient awareness and disease features. SISMAD should be considered in the differential diagnosis of patients presenting with unexplained abdominal pain, especially males, patients in the 5th decade of life, patients with hypertension, and patients with an enlarged SMA diameter or a maximum SMA diameter located on the LRV plane on plain CT. Mesenteric CTA or CECT should be recommended for the investigation of these conditions.

Combination treatment for superior mesenteric artery dissection: therapeutic challenge

Dissection of the superior mesenteric artery is a rare cause of abdominal pain, with a variable clinical picture. It is difficult to diagnose and there is no consensus on treatment options, which range from conservative treatment to open, endovascular, or combination repair. We describe the case of a 45-year-old man with isolated dissection of the superior mesenteric artery and persistent abdominal pain after conservative treatment had been attempted. He underwent open surgical revascularization due to the location and complexity of the dissection. Treatment consisting of endarterectomy, arterioplasty with bovine pericardium patch, and retrograde access to open the mesenteric artery with a stent was successful. Abdominal angina was completely resolved after the condition had stabilized. A combination of open and endovascular approaches should be considered as treatment for cases of isolated complex dissection of the superior mesenteric artery.

Isolated Superior Mesenteric Artery Dissection: A Novel Etiology and a Review

Isolated superior mesenteric artery dissection (ISMAD) is a rare pathology with multifactorial etiology. The aim of this article is to provide a narrative review of the latest literature about ISMAD. Case reports, series, and recent meta-analyses were included. This review is introduced with a brief case report of a rare etiology of ISMAD, followed by a discussion of its etiology, clinical presentation, diagnosis, classification, and treatment, and we report a new cause of ISMAD, that is, blunt abdominal trauma. The etiology of ISMAD is multifactorial, consisting of anatomic, genetic, and systemic components. ISMAD is more common among middle-aged males and in East Asia. Its clinical presentation ranges from asymptomatic to mesenteric ischemia, albeit mortality remains <1%. It is diagnosed and classified mostly by computed tomography angiography, and there are five classification systems for ISMAD, though traumatic etiology may be added. The treatment of ISMAD is mostly conservative, with a success rate exceeding 90%. Endovascular stenting is second line, reserved so far for failed medical management, though its role is expanding to include earlier management of symptomatic patients, while open surgical repair is left for acute mesenteric ischemia with bowel compromise.

Anastomotic stenosis of a reconstructed dissecting superior mesenteric artery aneurysm undetectable by intraoperative indocyanine green angiography: A case report

Intraoperative evaluation of blood flow using ICG angiography revealed no significant abnormality. However, the anastomotic stenosis was revealed by postoperative CT angiography; more precise intraoperative evaluation methods need to be developed.

Management of Symptomatic Spontaneous Isolated Superior Mesenteric Artery Dissection: A Single Centre Experience with Mid Term Follow Up

OBJECTIVE

This study aimed to report a single centre management experience and mid term outcomes for symptomatic spontaneous isolated superior mesenteric artery dissection (SISMAD).

METHODS

This was a retrospective observational study. Between 1 August 2012, and 30 June 2018, consecutive patients with symptomatic SISMAD were included. Patient demographics, clinical symptoms, comorbidities, risk factors, and dissection characteristics were obtained. The treatment regimens and clinical and follow up outcomes were reviewed and analysed. A chi square test, Fisher's exact test, or one way analysis of variance was used to compare variables between the groups. Binary logistic regression was used to determine predictive factors for failed conservative treatment. The cumulative rate of complete dissection remodelling was calculated using a Kaplan-Meier curve.

RESULTS

Sixty-two patients (mean age, 56.0 ± 9.3 years) were included. Patients at risk of intestinal ischaemia or dissecting aneurysm rupture were considered to be high risk patients (Group 1, n = 16) and received primary endovascular treatment. The remaining patients were considered low risk (Group 2, n = 46) and received primary conservative treatment. Symptom relief was observed in 82.6% of patients in Group 2. Finally, failed conservative treatment was observed in 50% of the low risk patients. Dissection length ≥50 mm was an independent risk factor for failed conservative treatment (p = .019; OR 4.68, 95% CI 1.29-16.98). During a median follow up of 30.5 months (interquartile range, 17.5, 58.3), patients with stents had a higher complete dissection remodelling rate than those without stents.

CONCLUSION

This study found that conservative treatment showed satisfactory symptom resolution for low risk SISMAD patients. Endovascular stenting was associated with a high technical success and dissection remodelling rate. This treatment modality might be reserved for patients with high risk SISMAD or failed conservative treatment. In addition, a dissection length ≥50 mm was a risk factor for failed conservative treatment.

The impact of endovascular treatment on clinical outcomes of stable symptomatic patients with spontaneous superior mesenteric artery dissection

OBJECTIVE

To evaluate the efficacy and clinical outcomes of endovascular treatment for superior mesenteric artery dissection (SMAD) and its effect on superior mesenteric artery (SMA) remodeling compared with medical management alone after successful initial medical management.

METHODS

In this retrospective analysis, all patients with spontaneous SMAD at a single institution were identified from March 2007 to August 2019. The primary outcomes were freedom from major adverse events (MAEs, a composite of dissection-related death, the recurrence of mesenteric ischemia symptoms, and a requirement for intervention). The secondary outcomes were morphologic remodeling of the dissections and stenosis or occlusion of the SMA.

RESULTS

A total of 94 patients with SMAD who underwent successful initial medical management (91 males; mean age, 50.4 ± 6.3 years) were enrolled in the study. Fifty-seven (60.6%) received medical management alone, and 37 (39.4%) underwent endovascular repair after initial medical management. In the endovascular group, the technical success rate was 86.5% (32 of 37). During a mean follow-up period of 33.6 ± 26.2 months (range, 1-120 months), nine (9.6%) patients experienced a recurrence of abdominal pain, and six had additional interventions for SMAD. The patients in the endovascular group showed more complete or partial remodeling (22 [81.1%] vs 24 [44.4%]; P < .0001) or unchanged dissections (5 [13.5%] vs 23 [42.6%]; P = .0001) than those in the conservative group. Survival analysis showed that the estimated MAE-free survival rates were 95.6%, 88.9%, and 85.4% at 1, 3, and 5 years, respectively. There was a higher freedom from SMA stenosis or occlusion in the endovascular group (log rank P = .046).

CONCLUSIONS

Endovascular treatment and medical management alone result in similar MAE-free survival for patients with SMAD after successful initial medical management. Moreover, endovascular therapy is associated with a higher complete remodeling rate and greater freedom from SMA stenosis or occlusion.

Endovascular Management of Isolated Superior Mesenteric Artery Dissecting Aneurysm by Retrograde Catheterization Via Collaterals from the Celiac Artery

Isolated superior mesenteric artery (SMA) dissecting aneurysm is frequently symptomatic and potentially catastrophic; thus, it usually requires endovascular treatment. The endovascular management can be challenging in certain cases as catheterization of the collapsed true lumen is often very difficult. This case report is to describe a new approach for catheterization of the true lumen of the SMA in a case of isolated SMA dissecting aneurysm. A 63-year-old male with an SMA dissecting aneurysm underwent stent-graft placement for treatment. Catheterization of the true lumen via the anterograde approach was unsuccessful because of angulation and collapse of the SMA true lumen as a result of the dissecting aneurysm. A guidewire was passed through the collaterals from the celiac artery and retrogradely passed across the collapsed SMA true lumen into the aorta. We then used a snare that had been delivered through the contralateral femoral access to capture and retrieve the guidewire. A delivery system was advanced into the SMA, and a stent graft was successfully deployed to occlude the dissecting aneurysm. This report introduces a new feasible retrograde approach that provides access to the SMA true lumen via celiac collaterals in cases of difficult antegrade catheterization of an SMA dissecting aneurysm.