An anatomical study of the origins courses and distributions of the transverse branches of lumbar arteries at the L1-L4 levels.

Pseudoaneurysms of the lumbar arteries following transforaminal lumbar interbody fusion (TLIF) are rare postoperative complications that usually occur around the transverse process. However, there are few detailed descriptions of the transverse branch and other branches of the dorsal branches at the L1-L4 disks. STUDY DESIGN: Ten adult embalmed cadavers were anatomically studied. OBJECTIVES: The purposes of the study were to describe the vascular distribution of the dorsal branches, especially the transverse branches, at the L1-L4 levels and provide information useful for TLIF. METHODS: Ten embalmed cadavers studied after their arterial systems were injected with red latex. The quantity, origin, pathway, distribution range and diameter of the branches were recorded and photographed. RESULTS: The transverse branch appeared in all 80 intervertebral foramina. The transverse branch was divided into 2 types: In type 1, the arteries divided into superior branches and inferior branches; the arteries in type 2 divided into 3 branches (superior, intermedius and inferior branches). CONCLUSIONS: The transverse branches of the dorsal arteries are common structures from L1 to L4, and 2 types of transverse branches were found. A thorough understanding of the dorsal branches, especially the transverse branches of the lumbar artery, may be very important for reducing both intraoperative bleeding during the surgery and the occurrence of pseudoaneurysms after transforaminal lumbar interbody fusion.

Midterm Outcomes of Endovascular Abdominal Aortic Aneurysm Repair with Prevention of type 2 Endoleak by Intraoperative Aortic Side Branch Coil Embolization.

OBJECTIVE: The midterm results of endovascular abdominal aortic aneurysm repair (EVAR) with aortic side branch coil embolization during EVAR was evaluated. METHODS: Our center began coil embolization for all patent inferior mesenteric artery (IMA) and lumbar artery (LA) with an inner diameter more than 2.0 mm during EVAR since June 2015. When four or more LA were patent, coil embolization for LA with inner diameter 2.0 mm or less was done. EVAR without aortic side branches coil embolization was performed for 59 patients prior to June 2015 (control group) and 79 patients underwent EVAR with coil embolization during EVAR (coil group). The success rate of coil embolization for IMA and LA was evaluated in coil group. The frequency of type 2 endoleak (T2EL), freedom from aneurysm sac expansion (5 mm or more) rate and the rate of the aneurysm sac shrinkage (10 mm or more) were compared between the coil and control groups. Additionally, multiple logistic regression analysis for all patients was conducted to analyze whether IMA patency and the number of patent lumbar artery at the end of EVAR were the risk factors of the aneurysm sac expansion of 5 mm or more. RESULTS: The success rate of IMA coil embolization was 96.4% and that of LA was 74.5%. Compared to the control group, the frequency of T2EL was significantly lower in coil group at 7 days (1.3% vs. 60.4%, P <0.0001) and at 6 months (2.1% vs 38.2%, P <0.0001) after EVAR. The freedom from aneurysm sac expansion rate was significantly better in the coil group at 5 years (100% in coil group and 65.2% in control group, P = 0.002). The rate of aneurysm sac shrinkage was significantly better in coil group (15.5% vs. 2.0% at 1 year, 42.8% vs. 6.3% at 2 years and 53.4% vs. 17.8% at 3 years, p = 0.0007). The risk of aneurysm sac expansion of 5 mm or more was estimated to be 11 times greater when the IMA was patent, and 4.9 times greater when 3 or more LAs were patent at the end of EVAR. CONCLUSION: When IMA was occluded and the number of patent LA became 2 or less by aortic side branch coil embolization during EVAR, favorable mid-term results were safely obtained and good long-term result could be expected with EVAR.

Resuscitative Endovascular Balloon Occlusion of the Aorta for Blood Control in Lumbar Spine Tumor Resection Surgery: A Technical Note.

OBJECTIVES: To describe the technique of the aorta balloon occlusion, and evaluate the blood loss in lumbar spine tumor surgery assisted by aortic balloon occlusion, and to observe the balloon-related complications. METHODS: Six patients with lumbar spine tumor underwent resuscitative endovascular balloon occlusion of the aorta prior to tumor resections in our institution between May 2018 to January 2021. Medical records including demographic, diagnosis, tumor location, surgical approach, intraoperative blood loss, surgical duration, and perioperative balloon-related complication were evaluated retrospectively. RESULTS: This series included four males and two females, with a median age of 50 years (range 22 to 69). Of these, three primary tumors were plasmacytoma, giant cell tumor of bone, and osteosarcoma, while recurrence of undifferentiated pleomorphic sarcoma (UPS), recurrence of giant cell tumor of bone (GCT), and metastatic thyroid cancer were diagnosed in cases 1, 6, and 2, respectively. L2 was involved in cases 1 and 5. L3 was involved in case 6. L4 was involved in case 2, 3, and 6. L5 was involved in case 4. One-stage total en bloc resection surgery (TES) was accomplished in all patients; of this series, signal anterior approach was conducted in case 1, signal posterior approach was utilized in cases 2, 3, and 6, while combined anterior and posterior approach was performed in cases 4 and 5. The median intraoperative blood loss was 1683 mL and ranged from 400 to 3200 mL with a median surgical duration of 442 min and a range from 210 to 810 min. During the perioperative period, no serious balloon-related complications occurred. CONCLUSIONS: Endovascular balloon occlusion of the aorta successfully controls intraoperative exsanguination, contributing to a more radical tumor resection and a low rate of tumor cell contamination in lumbar tumor surgery.

Massive Pulmonary Embolism due to Inferior Vena Cava Thrombosis Related to Compression by Lumbar Artery Pseudoaneurysm. A Case Report and Review of Literature.

Lumbar artery pseudoaneurysm (LAPA) is a pathology infrequently described in the literature. The most frequent complications are the expansion and rupture of the pseudoaneurysm. Reports of association between PE with LAPA have not yet been described. We present a 53-year-old male patient with LAPA whose expansion caused compression of the inferior vena cava and subsequently PE. He underwent mechanical thrombectomy and inferior cava vein filter placement associated with embolization of the LAPA. Despite the severe clinical profile, the patient was discharged with a favorable postoperative course without complications. This case report also includes a review of the literature.

Distance measurements and origin levels of the coeliac trunk, superior mesenteric artery, and inferior mesenteric artery by multiple-detector computed tomography angiography.

The aim of this study is to determine vertebral levels of the coeliac trunk, the superior mesenteric artery, and the inferior mesenteric artery originated from the abdominal aorta and to calculate the distance measurements between these arteries and between these arteries and the aortic bifurcation by multidetector computed tomography angiography technique. It was determined that the nine different vertebral levels of the coeliac trunk, the nine different vertebral levels of the superior mesenteric artery, and the eleven different vertebral levels of the inferior mesenteric artery. The distance measurements between the coeliac trunk and the superior mesenteric artery, the inferior mesenteric artery, the aortic bifurcation were found significant between female and male. In this study, it was determined more different levels than the levels described in classical anatomy. The preoperative information of these morphological variations can contribute to the reduction of surgical time and perioperative vascular complications especially for anterior lumbar interbody fusion and defining the location of the primary lymphatic drainage site for gastrointestinal malignancies.

Spinal neurovascular complications with anterior thoracolumbar spine surgery: a systematic review and review of thoracolumbar vascular anatomy.

OBJECTIVE: Spinal cord infarction due to interruption of the spinal vascular supply during anterior thoracolumbar surgery is a rare but devastating complication. Here, the authors sought to summarize the data on this complication in terms of its incidence, risk factors, and operative considerations. They also sought to summarize the relevant spinal vascular anatomy. METHODS: They performed a systematic literature review of the PubMed, Scopus, and Embase databases to identify reports of spinal cord vascular injury related to anterior thoracolumbar spine procedures as well as operative adjuncts and considerations related to management of the segmental artery ligation during such anterior procedures. Titles and abstracts were screened, and studies meeting inclusion criteria were reviewed in full. RESULTS: Of 1200 articles identified on the initial screening, 16 met the inclusion criteria and consisted of 2 prospective cohort studies, 10 retrospective cohort studies, and 4 case reports. Four studies reported on the incidence of spinal cord ischemia with anterior thoracolumbar surgery, which ranged from 0% to 0.75%. Eight studies presented patient-level data for 13 cases of spinal cord ischemia after anterior thoracolumbar spine surgery. Proposed risk factors for vasculogenic spinal injury with anterior thoracolumbar surgery included hyperkyphosis, prior spinal deformity surgery, combined anterior-posterior procedures, left-sided approaches, operating on the concavity side of a scoliotic curve, and intra- or postoperative hypotension. In addition, eight studies analyzed operative considerations to reduce spinal cord ischemic complications in anterior thoracolumbar surgery, including intraoperative neuromonitoring and preoperative spinal angiography. CONCLUSIONS: While spinal cord infarction related to anterior thoracolumbar surgery is rare, it warrants proper consideration in the pre-, intra-, and postoperative periods. The spine surgeon must be aware of the relevant risk factors as well as the pre- and intraoperative adjuncts that can minimize these risks. Most importantly, an understanding of the relevant spinal vascular anatomy is critical to minimizing the risks associated with anterior thoracolumbar spine surgery.

Median Sacral Artery Rupture as a Complication of Posterior-Only Approach of L4 Total En Bloc Spondilectomy: A Case Report.

CASE: A 6-year-old patient with Ewing sarcoma at L4 who was treated with total en bloc spondilectomy (TES) through a posterior-only approach. During the dissection of the anterior L4 body, there was uncontrollable bleeding from an unknown origin, which needed packing, massive transfusion, and urgent laparotomy. A median sacral artery (MSA) rupture was identified as the cause of this massive bleeding. Eventually, the patient was successfully stabilized. CONCLUSIONS: To our knowledge, this is the first reported intraoperative bleeding of the MSA related to a lumbar TES through posterior-only approach. This life-threatening complication should be considered when planning for this type of surgery.

Multi-Site Optical Monitoring of Spinal Cord Ischemia during Spine Distraction.

Optimal surgical management of spine trauma will restore blood flow to the ischemic spinal cord. However, spine stabilization may also further exacerbate injury by inducing ischemia. Current electrophysiological technology is not capable of detecting acute changes in spinal cord blood flow or localizing ischemia. Further, alerts are delayed and unreliable. We developed an epidural optical device capable of directly measuring and immediately detecting changes in spinal cord blood flow using diffuse correlation spectroscopy (DCS). Herein we test the hypothesis that our device can continuously monitor blood flow during spine distraction. Additionally, we demonstrate the ability of our device to monitor multiple sites along the spinal cord and axially resolve changes in spinal cord blood flow. DCS-measured blood flow in the spinal cord was monitored at up to three spatial locations (cranial to, at, and caudal to the distraction site) during surgical distraction in a sheep model. Distraction was halted at 50% of baseline blood flow at the distraction site. We were able to monitor blood flow with DCS in multiple regions of the spinal cord simultaneously at ∼1 Hz. The distraction site had a greater decrement in flow than sites cranial to the injury (median -40 vs. -7%,). This pilot study demonstrated high temporal resolution and the capacity to axially resolve changes in spinal cord blood flow at and remote from the site of distraction. These early results suggest that this technology may assist in the surgical management of spine trauma and in corrective surgery of the spine.

Distribution of the Spinal Arteries in Adult Patients with Lumbar Spondylolysis.

INTRODUCTION : The pathology of lumbar spondylolysis is generally thought to begin with a stress fracture in adolescence. Stress fractures of the lower extremities occur in watershed areas with a poor vascular supply because of an inability to respond to stress and heal. This pathology has not been well researched in the lumbar spine. The aim of this study was to evaluate the distribution of the spinal arteries in patients with lumbar spondylolysis. METHODS : The extraosseous distribution of the arteries around the pars interarticularis was retrospectively investigated in 14 patients with colon cancer who underwent abdominal contrast-enhanced computed tomography (CE-CT) as part of a preoperative assessment at our hospital and were found to have spondylolysis at L5. RESULTS : All patients were found to have terminal-stage spondylolysis at L5 (1 unilateral, 13 bilateral). L5 segmental artery was absent in all cases. However, separate spinal arteries supplying the pars interarticularis at L5 were found above and below the transverse process at this level. CONCLUSION : All the patients had two separate arteries originating from the cranial and caudal sides that distributed to the superior and inferior articular processes, suggesting that the pars interarticularis is a posterior element containing a vascular watershed area. J. Med. Invest. 67 : 62-66, February, 2020.

Republished: A lumbar arteriovenous fistula presenting with intraventricular hemorrhage and hydrocephalus.

Pediatric spinal vascular malformations are rare entities that typically present with symptoms from their effect on surrounding structures. Here we report a unique case of lumbar spinal dural/perimedullary arteriovenous fistula (AVF) that presented with intraventricular hemorrhage and hydrocephalus. The previously healthy child presented with lethargy and headache, and initial imaging revealed only ventriculomegaly with trace intraventricular blood. His mental status improved with CSF diversion via an external ventricular drain. Further workup revealed a spinal AVF that was treated via endovascular embolization. His course was complicated by vasospasm requiring endovascular treatment and he eventually required ventriculoperitoneal shunt placement. He made a full recovery and has returned to his normal activities. This is a unique case of spinal AVF presentation and highlights the importance of considering imaging of the entire neuroaxis during workup for hydrocephalus.

The position of the aorta relative to the spine in patients with adult degenerative scoliosis.

STUDY DESIGN: A retrospective analysis was conducted to analyze the position of the aorta by MRI in patients with adult degenerative scoliosis. OBJECTIVE: This study aimed to investigate the relative anatomic positions of the aorta and spine in patients with adult degenerative scoliosis (ADS). Aorta injury is a rare complication of spinal surgeries. However, there would be a disastrous consequence once it happened. Therefore, knowing about the position of aorta is of great importance. METHODS: A retrospective analysis was performed in 90 patients with ADS and 132 participants without spine deformity. ADS patients were divided into several groups such as left scoliosis, left scoliosis with thoracolumbar kyphosis, right scoliosis, and right scoliosis with thoracolumbar kyphosis. The aorta-vertebrae angle (α) and aorta-vertebrae distance (d) in each level of T12-L4 were measured by using a Cartesian coordinate system. t test of independent samples was performed, α and d were compared, and Pearson correlation analysis was employed for α, d, and X-ray radiographic measurements. RESULT: The changes of α were not statistically significant (P > 0.05) in LS and LKS groups but d (P < 0.05) was longer in LKS group compared with the control group. In the right malformed group, there was no significant change in the angle (P > 0.05) in the abdominal aorta but longer d (P < 0.05) than the normal group. There was longer d in the RKS group compared with the RS group (P < 0.05). Pearson correlation analysis showed that there was a positive correlation between d and TLK (r = 0.439, P < 0.05). CONCLUSION: In patients with ADS, a relative normal position is maintained between the aorta and vertebrae. While the aorta is slightly away from the left pedicle in RS patients and farther away in patients with kyphosis, the angle of kyphosis would become bigger and d becomes longer. Therefore, the surgeons should be aware of the changes of the aorta position to avoid the disastrous vessel injuries.

Iatrogenic Common Iliac Vessel Injury During Routine Degenerative Lumbar Spine Surgery: Report of 2 Cases and Review of Literature.

BACKGROUND: Injury of the iliac vessels is a rare complication of lumbar spine surgery with potentially life-threatening consequences. We present 2 cases of iliac vessel injury that were treated with minimally invasive techniques. CASE DESCRIPTION: The first case was a laceration of the common iliac artery during a simple L4-L5 discectomy in which the injured artery was secured by stent implantation. The second case was an example of injury to the left iliac common vessel leading to acute lower limb ischemia and arteriovenous fistula formation after lumbar spinal canal stenosis surgery. The patient was treated in 2 steps. First, a temporary femorofemoral bypass was implanted to revascularize the right lower limb. The second step involved stent implantation in the right common iliac artery to close the arteriovenous fistula. Both patients were treated without extensive laparotomy and had good clinical outcomes. CONCLUSIONS: This case series emphasizes the benefit of quick minimally invasive vascular repair available in multidisciplinary centers.

A distraction technique using reduction multi-axial screws for open reduction of high-grade lumbar posterior dislocation:a case report and literature review.

BACKGROUND: L3 vertebral fractures with posterior dislocation are rare and usually secondary to high-energy trauma. To assess the outcome of a valuable distraction technique, using long-tail multiaxial pedicle screw which we have employed in reduction of L3 vertebral fracture with posterior dislocation, and emphasize the importance of preoperative blood vessel evaluation. CASE PRESENTATION: A 47-year-old patient fell from a height of 4 m and was paralyzed. Computed tomography scan revealed a three-column ligamentous injury with posterior fracture-dislocation of the L3 vertebral body. Computed tomography angiography showed that the third lumbar artery was ruptured without active bleeding. The patient underwent posterior approach with reduction, transpedicular fixation, and posterolateral fusion with autologous bone graft. Finally, Vertebral reduction and sagittal balance were achieved and patients recovered well after operation. CONCLUSION: Preoperative blood vessel evaluation is very important to avoid massive bleeding during the surgery, and the standard technique which can achieve good reduction is easy to understand, perform, and is reproducible.

Effect of diminished flow in rabbit lumbar arteries on intervertebral disc matrix changes using MRI T2-mapping and histology.

BACKGROUND: Impaired lumbar artery flow has been reported in clinical and epidemiological studies to be associated with low back pain and lumbar disc degeneration. However, it has not been experimentally demonstrated that impaired lumbar artery flow directly induces intervertebral disc (IVD) degeneration by affecting IVD matrix metabolism. The purpose of this study was to evaluate whether ligation of the lumbar artery can affect degenerative changes in the rabbit IVD. METHODS: New Zealand White rabbits (n = 20) were used in this study. Under general anesthesia, the third and fourth lumbar arteries were double-ligated using vascular clips. The blood flow to the L3/L4 disc (cranial disc) was reduced by ligation of the third lumbar artery and that of the L5/L6 disc (caudal disc) by ligation of the fourth lumbar artery. The blood flow to the L4/L5 disc (bilateral disc) was decreased by ligation of both the third and fourth lumbar arteries. The L2/L3 disc was used as the control. Disc height was radiographically monitored biweekly until 12 weeks after surgery. The rabbits were sacrificed at 4, 8, and 12 weeks after surgery and magnetic resonance imaging (MRI) T2-mapping, histology and immunohistochemistry were assessed. RESULTS: Lumbar artery ligation did not induce significant changes in disc height between control and ischemic discs (cranial, bilateral and caudal discs) during the 12-week experimental period. T2-values of ischemic discs had no significant trend to be lower than those of the control L2/L3 discs. Histologically, Safranin-O staining changed following ligation of corresponding IVD lumbar arteries. Histological grading scores for disc degeneration, which correlated significantly with MRI T2-values, had significant changes after the surgery. Immunohistochemical analysis showed that the ligation of lumbar arteries significantly affected a change in the percentage of HIF-1α immunoreactive cells of ischemia discs compared to that of control discs four weeks after the surgery (p < 0.05). CONCLUSIONS: The MRI and histology results suggest that diminished flow in lumbar arteries induce mild changes in the extracellular matrix metabolism of rabbit IVDs. These matrix changes, however, were not progressive and differed from the degenerative disc changes seen in the process of human IVD degeneration.

Iliolumbar Vein: Anatomy and Surgical Importance During Lateral Transpsoas and Oblique Approaches to Lumbar Spine.

OBJECTIVE: Safe surgical approaches to the anterolateral lumbar spine require a good working knowledge of the anatomy and anatomic variations of this region. As the iliolumbar vein is in the vicinity of both oblique and lateral transpsoas approaches to the lower lumbar spine, the following study was performed to better elucidate its anatomy, variations, and position during such surgical procedures. METHODS: Fifteen (30 sides) fresh frozen adult cadavers underwent dissection of the iliolumbar vein (ILV). The origin, course, variants, relations, and morphometrics of each vein were documented. Fluoroscopy of the vessels was performed. Lastly, anterior oblique and lateral transpsoas approaches to the lumbar spine were carried out in order to evaluate for potential ILV injury. RESULTS: An ILV was found on all but 2 sides (93.3%). It arose as a common trunk from the common iliac vein on 14 sides. Left ILVs tended to have a more distal origin than right ILVs. ILVs had a mean length of 3.7 cm and a mean width of 0.9 cm and were significantly larger on right versus left sides (P < 0.05). Left-sided ILVs tended to have more branches than right-sided veins. The majority of vertical branches of the ILV traveled anterior to the ventral rami of the lumbar spinal nerves, most commonly L4. The ILV and, in particular, its vertical branches coursed next to the L4 and L5 vertebrae. CONCLUSIONS: The ILV should be considered during both oblique and lateral transpsoas approaches to the lumbar spine.

Relationship Between Apoptosis of Endplate Microvasculature and Degeneration of the Intervertebral Disk.

OBJECTIVE: To explore the relationship between intervertebral disk degeneration and endplate microvasculature, and to determine the role of apoptosis in the pathophysiology underlying end plate microvasculature. METHODS: Twelve 6-month-old rabbits were randomly divided into group A (control group where animals underwent a sham operation, in which the loading device was implanted but without loading) and group B (degeneration group, where a calibrated spring within the loading device would immediately create static shear force of 50 N to the disk of L4-5). Paraffin-embedded midsagittal sections of the L4-5 disk were obtained 4 weeks after surgery in the both groups. Sections were stained with cluster of differentiation (CD) 31 immunohistochemistry to measure the blood vessel density in the endplate, with CD31 immunofluorescence and terminal dUTP nick-end labeling (TUNEL) to detect the apoptosis of vascular endothelial cells in the endplate. RESULTS: After 4 weeks, the microvasculature density was 91 ± 8 vessels/mm2 in group A and 47 ± 2 vessels/mm2 (P < 0.001) in group B, demonstrating that vessels were reduced in the endplate of intervertebral disk degeneration. CD31 immunofluorescence and TUNEL showed that apoptosis of vascular endothelial cells exists in the endplate of intervertebral disk degeneration. CONCLUSIONS: The results of this study suggest that apoptosis of vascular endothelial cells results in a decrease in endplate microvasculature density, further affecting the pathologic process of intervertebral disk degeneration.

Anatomic Considerations in the Lateral Transpsoas Interbody Fusion: The Impact of Age, Sex, BMI, and Scoliosis.

STUDY DESIGN: This is a retrospective case series. OBJECTIVE: Define the anatomic variations and the risk factors for such within the operative corridor of the transpsoas lateral interbody fusion. SUMMARY OF BACKGROUND DATA: The lateral interbody fusion approach has recently been associated with devastating complications such as injury to the lumbosacral plexus, surrounding vasculature, and bowel. A more comprehensive understanding of anatomic structures in relation to this approach using preoperative imaging would help surgeons identify high-risk patients potentially minimizing these complications. MATERIALS AND METHODS: Age-sex distributed, naive lumbar spine magnetic resonance imagings (n=180) were used to identify the corridor for the lateral lumbar interbody approach using axial images. Bilateral measurements were taken from L1-S1 to determine the locations of critical vascular, intraperitoneal, and muscular structures. In addition, a subcohort of scoliosis patients (n=39) with a Cobb angle >10 degrees were identified and compared. RESULTS: Right-sided vascular anatomy was significantly more variant than left (9.9% vs. 5.7%; P=0.001). There were 9 instances of "at-risk" vasculature on the right side compared with 0 on the left (P=0.004). Age increased vascular anatomy variance bilaterally, particularly in the more caudal levels (P≤0.001). A "rising-psoas sign" was observed in 26.1% of patients. Bowel was identified within the corridor in 30.5% of patients and correlated positively with body mass index (P<0.001). Scoliosis increased variant anatomy of left-sided vasculature at L2-3/L3-4. Nearly all variant anatomy in this group was found on the convex side of the curvature (94.2%). CONCLUSIONS: Given the risks and complications associated with this approach, careful planning must be taken with an understanding of vulnerable anatomic structures. Our analysis suggests that approaching the intervertebral space from the patient's left may reduce the risk of encountering critical vascular structures. Similarly, in the setting of scoliosis, an approach toward the concave side may have a more predictable course for surrounding anatomy. LEVEL OF EVIDENCE: Level 3-study.

Pre-emptive nonselective perigraft aortic sac embolization with coils to prevent type II endoleak after endovascular aneurysm repair.

OBJECTIVE: Pre-emptive selective embolization of inferior mesenteric artery (IMA), lumbar arteries (LAs), and perigraft sac for prevention of type II endoleak (T2EL) has not been widely adopted. We perform pre-emptive nonselective perigraft aortic sac embolization with coils (PNPASEC) in patients at high risk for development of T2EL (four or more patent LAs, patent IMA ≥3 mm, and ≥30-mm aortic flow lumen). The goal of this study was to see whether PNPASEC decreases T2ELs requiring reinterventions. METHODS: All 266 patients undergoing elective endovascular aneurysm repair between September 1, 2007, and October 31, 2015, were retrospectively evaluated from a prospectively maintained database. Patients (N = 212; 211 men) with preoperative and postoperative contrast-enhanced computed tomography scans were included. Our PNPASEC technique involves leaving a wire in the sac after cannulation of the contralateral gate and inserting large (0.035-inch) coils into the sac after bifurcated graft deployment. T2EL and reintervention rates were compared between patients who underwent PNPASEC (group I) and those who met the criteria but did not have PNPASEC (group II) and those who did not meet the criteria (Group III). RESULTS: Forty-seven (22.2%) patients were PNPASEC candidates and 165 (77.8%) patients (group III) were not. Among PNPASEC candidates, 16 (7.5%) underwent PNPASEC (group I) and 31 (14.6%) did not (group II). There were no significant differences between groups in terms of comorbidities, aneurysm size, and anatomic and neck characteristics. Mean number of patent LAs was similar between group I (4.5 ± 0.8) and group II (4.5 ± 0.9), which was significantly greater than in group III (1.9 ± 1.3; P < .001); 43.6% of group III patients had patent IMA. Mean follow-up was 44 ± 25 months. T2EL at 6 months was observed in 48.4% in group II, 3.0% in group III, and 6.3% in group I (P < .001). Sac diameter increase was seen in 38.7% in group II vs 6.1% in group III and 6.3% in group I (P < .001), with complete sac shrinkage in 23.3% in group II vs 23.8% in group III and 50.0% in group I (P = .09). T2EL-related interventions were performed in 29.0% in group II vs 1.2% in group III and 6.3% in group I (P < .001). Any endoleak at last follow-up was seen in 25.8% in group II vs 2.4% in group III and none in group I (P < .001). CONCLUSIONS: Nonselective perigraft sac coil embolization in patients at high risk for T2EL (20% of patients undergoing endovascular aneurysm repair) is effective in preventing development of T2EL and is associated with decrease in sac size and reintervention rates.

Lumbar Artery Injury during Transforaminal Percutaneous Endoscopic Lumbar Discectomy: Successful Treatment by Emergent Transcatheter Arterial Embolization.

Injury to the lumbar artery during percutaneous endoscopic lumbar discectomy (PELD) is a very severe complication and only rarely reported. We present a 64-year-old patient with an injury to the right third lumbar artery during PELD which was successfully treated with intraoperative angiography and coil embolization. To our knowledge, this is the first report of the use of intraoperative angiography and coil embolization to treat a lumbar artery that had been lacerated during PELD.