[Clinical research progress of spinal epidural lipomatosis].

Objective: To review the clinical research progress of spinal epidural lipomatosis (SEL). Methods: The clinical studies on SEL at home and abroad in recent years were extensively reviewed, and the pathogenesis, clinical and imaging manifestations, and treatment status of SEL were summarized and analyzed. Results: SEL is a disease characterized by compression of the spinal cord and nerve roots due to abnormal accumulation of epidural adipose tissue in the spinal canal. Its prevalence and diagnosis rate are low and the pathogenesis is not fully understood. MRI is the most sensitive and specific diagnostic test for SEL. Surgical decompression and removal of excess adipose tissue are the only options for patients with acute SEL or those who have failed conservative management, and conservative management should be considered for other patients. Conclusion: SEL is a rare disease and related research still needs to be improved. In the future, high-quality, multi-center and large-sample studies will be of great significance for evaluating the choice of treatment methods and effectiveness of SEL patients.

Temperature change of epidural space by radiofrequency use in biportal endoscopic lumbar surgery: safety evaluation of radiofrequency.

PURPOSE: Articles evaluating radiofrequency (RF) safety are insufficient. Thus, the purpose of this study was to investigate RF safety during biportal endoscopic lumbar decompressive laminotomy by measuring epidural temperature after RF use. METHODS: Both in vitro cadaveric study and in vivo study were performed. The epidural temperature was measured at epidural space after RF use in three cadavers. The epidural temperature was measured and analysed according to RF mode, RF power, RF usage time, and saline irrigation patency. In the in vivo study, the epidural temperature was measured after biportal endoscopic surgery. Epidural temperatures were measured around ipsilateral and contralateral traversing nerve roots after 1-s use of RF. RESULTS: In the in vivo study, epidural space temperature was increased by 0.31 ± 0.16 °C ipsilaterally and 0.29 ± 0.09° contralaterally after RF use in coagulation mode 1. The epidural temperature of epidural space was increased by 0.21 ± 0.13 °C ipsilaterally and 0.15 ± 0.21 °C contralaterally after RF use in high mode 2. In the in vitro study, epidural temperature was significantly increased with a long duration of RF use and a poor patency of irrigation fluid. CONCLUSION: The use of RF in biportal endoscopic spine surgery might be safe. In order to reduce indirect thermal injuries caused by RF use, it might be necessary to reduce RF use time and maintain continuous saline irrigation patency well.

The Mysterious Role of Epidural Fat Tissue in Spine Surgery: A Comprehensive Descriptive Literature Review.

BACKGROUND: Though both neurosurgeons and orthopedic spinal surgeons are keenly aware of the clinical importance of epidural fat (EF), surgical practice varies amongst individual surgeons and across both fields. Thus, an in-depth understanding of the anatomical structure and composition of EF is vital, as it will play a significant role in the therapeutic management and the surgical choice of treatment. OBJECTIVE: We aim to extensively review the anatomical and biological properties of EF and further outline the surgical importance of EF management. STUDY METHODOLOGY: (i) MEDLINE search 1966-July 2019. Keywords: Review of the Literature. Authorship, Meta-analysis, Descriptive/Narrative overview; (ii) CINAHL search from 1982 to May 2019. Keywords: Review of the Literature spinal epidural fat; Authorship; Meta-analysis; Descriptive/Narrative overview; (iii) Hand searches of the references of retrieved literature; (iv) Personal and college libraries were searched for texts on research methods and literature reviews; and (v) 200 articles were downloaded, 50 were excluded because of similarity of topics and also because of new update on the same topics. (vi) Discussions with experts in the field of reviews of the literature. DISCUSSION: Though excessive or reductive amounts of EF usually exacerbates neurological symptoms and lead to various pathologic conditions such as spinal epidural lipomatosis, but there is no basic science, experimental, or clinical research that proves the role of EF in the aforementioned pathologic situations. CONCLUSION: Anatomical illustration, biological function and properties of EF knowledge may lead to changes in the stages of the surgical approach to avoid postoperative complications. However, the role of EF is exclusively bound to a scientific hypothesis as one cannot be sure if an excessive or reductive amount in EF is entirely responsible for the pathologic findings, or just only an incidental finding.

Histopathological Study of the Effects of Dura Adhesive Agents Used in Spinal Surgery Practice on Spinal Epidural Fibrosis in Experimental Animal Model.

Objective: Histopathological examination of the effects of Tisseel, Cova, Glubran and Coseal, which are used for sealing purposes in spinal surgery practice, on epidural fibrosis is aimed. Methods: Forty Sprague Dawley rats were randomly divided into five groups in our study as Group 1 (n=8) control group (Laminectomy); Group 2 (n=8) Cova group (Laminectomy + Cova); Group 3 (n=8) Tissel group (Laminectomy + Tisseel); Group 4 (n=8) Coseal group (Laminectomy + Coseal); and Group 5 Glubrane group (Laminectomy + Glubrane). Control group was only applied laminectomy. After laminectomy to other groups, Cova was applied to the 2nd group, Tissel to the 3rd group, Coseal to the 4th group and Glubran to the 5th group in surgical fields. After the rats were monitored in separate cages for 6 weeks after the operation, the relevant spinal level was extracted and the samples were examined histopathologically and the results were evaluated statistically. Results: It was found that there was a statistically significant difference in Tisseel and Glubran groups in terms of fibrosis grading compared to the control group, and this had a positive effect on fibrosis. Compared to the control group, there was no statistically significant difference on fibrosis in Cova and Coseal groups. Conclusion: As dura adhesive agents used in spinal surgery practice did not increase spinal epidural fibrosis statistically significantly, we concluded that these products can be used safely during spinal surgery if necessary.

Minimally Invasive Surgical Treatment of Extensive Spinal Epidural Abscess With Unilateral Laminotomy for Bilateral Decompression Using an Ultrasonic Bone Curette: A Technique Note.

BACKGROUND: An extensive spinal epidural abscess is a devasting infection of the multiple-level epidural space. Emergent surgical decompression is required to remove the abscess and decompress the affected spinal cord. This study evaluated the efficacy of unilateral laminotomy for bilateral decompression (ULBD) in the treatment of extensive spinal epidural abscesses. METHODS: Three patients with extensive spinal epidural abscesses (epidural abscess involving more than 5 vertebral levels) were treated with the ULBD technique between September 2019 and August 2020. An ultrasonic curette was used for over-the-top decompression. Surgical drainage of the epidural abscess was performed concurrently with sublaminar drilling on top of the dura sac by using cold saline to automatically maintain the effluent in the ultrasonic curettage device. RESULTS: The 3 patients were men, with a mean age of 65.7 years. Diabetes mellitus, fever, and paraplegia were reported in all 3 patients. Escherichia coli, Staphylococcus aureus, and Streptococcus intermedius were cultured separately. The mean operative time was 163 minutes, and the mean estimated blood loss was 160 mL. All patients fully recovered from neurologic deficits and returned to preinjury levels of functioning at the final follow-up. CONCLUSIONS: As a minimally invasive technique, ULBD is a safe and effective treatment for extensive spinal epidural abscesses in critically ill patients. Moreover, the use of an ultrasonic bone curette not only safely accelerates over-the-top decompression but also flushes the epidural abscess with copious amount of cold saline.

Extensive Symptomatic Thoracolumbar Epidural Lipomatosis Treated With Minimally Invasive Hemilaminectomies: Technical Case Report.

BACKGROUND AND IMPORTANCE: Spinal epidural lipomatosis is a rare condition commonly associated with chronic corticosteroid use and obesity that involves deposition of adipose tissue in the epidural space of the spinal canal. This accumulation of adipose tissue may cause compression of the spinal cord and/or nerve roots and result in compressive symptoms such as myelopathy or radiculopathy. Spinal involvement is usually confined to either the thoracic or lumbar spine but can infrequently affect both regions. Depending on pre-existing conditions, treatment options include weight loss and discontinuation of exogenous steroid use, both of which have been shown to be effective therapeutic methods. Surgical decompression may be useful for appropriately selected patients in whom conservative therapy has failed or who experience acute neurological deterioration, although this is rarely indicated. CLINICAL PRESENTATION: In this study, we describe a patient receiving long-term corticosteroid therapy who presented with symptomatic epidural lipomatosis that involved the thoracic and lumbar spine. She was treated with decompression by continuous T3-L5 hemilaminectomies performed through 5 small incisions of alternating laterality. After surgery, the patient experienced clinical improvement and was able to return to her baseline. CONCLUSION: We illustrate a successful spinal decompression of extensive epidural lipomatosis through a less-invasive surgical approach using several small incisions to accomplish uninterrupted hemilaminectomies. This alternative approach to a standard continuous incision can be considered in cases of extensive spinal epidural lipomatosis in patients with multiple medical comorbidities in whom wound healing is believed to be an issue and for whom minimizing blood loss is crucial.

IgG4-related Pachymeningitis as a Cause of Spinal Epidural Compression: Can Intraoperative Frozen Sections Predict the Underlying Pathology?

At times, spinal lesions are part of systemic manifestations of autoimmune disease. Awareness regarding their clinicopathological spectrum, particularly the lesions which usually respond to steroids/immunotherapy, is essential to avoid unwanted surgical morbidity. We discuss a case of a young-man presenting with thoracic spinal epidural compressive lesion which was indeed a manifestation of IgG4-related hypertrophic pachymeningitis. The mass was firmly adherent to the dura and extended into left neural foramen/paravertebral space which precluded complete excision. Frozen sections suggested fibro-inflammatory stroma with large areas of fibrosis and lymphoplasmacytic infiltrate. After subtotal excision, the patient improved with medical therapy at 1-year follow-up. Although uncommon, the case highlights the need to consider spinal presentation of this rare entity, especially in the context of autoimmune disorders or even in isolation. In this regard, intraoperative frozen section can hint the underlying inflammatory/autoimmune pathology, guide further course of surgery as well as limit unwarranted operative morbidity.

Lumbar Epidural Lipomatosis is Increased in Patients With Morbid Obesity and Subsequently Decreases After Bariatric Surgery.

BACKGROUND: Spinal epidural lipomatosis (SEL) is characterized by symptomatic neurogenic compression from adipose tissue in the spinal canal. The question arises whether patients with morbid obesity have higher volumes of epidural adipose tissue (EAT) in their lumbar spinal canal compared with patients with a normal weight, and to what extent this decreases after bariatric surgery. METHODS: In this explorative study the lumbar EAT volume was assessed in 25 patients with morbid obesity (body mass index [BMI] >40) using available lumbar magnetic resonance imaging (MRI) prior to their bariatric surgery. An age- and sex-matched control group (n = 25) of patients with a normal weight (BMI 20-25) was used for comparison. Participants from the obesity group underwent a postoperative control MRI. RESULTS: The mean volume of EAT per MRI slice of the group of patients with obesity was significantly higher than for the group of patients with normal weight (mean: 83.3 ± 30.7 mm3 vs. mean 56.5 ± 25 mm3; P < 0.001). Fifteen participants with obesity (15 of 25) agreed to undergo a follow-up MRI. There was a significant decrease in EAT volume per MRI slice for these 15 participants (mean 82 ± 25.5 mm3 vs. 46 ± 20.0 mm3; P < 0.001) over time up to 3.6 (range: 1.2-6.0) years after bariatric surgery. CONCLUSIONS: Patients with obesity have significantly larger volumes of EAT in comparison with patients with normal weight. After bariatric surgery, a significant weight loss coincided with a significant volumetric reduction of this adipose tissue in the spinal canal. Future prospective studies in patients with symptomatic SEL may elucidate whether decreases in EAT volume influence concurrent neurogenic claudication symptoms.

Epidural Fat Tissue Is More Effective for Scar Prevention Than Conventional Subcutaneous Fat Grafting After Laminectomy in a Mouse Model.

STUDY DESIGN: Basic science study. OBJECTIVE: The aim of this study was to examine whether epidural fat tissue (EFT) transplantation can prevent epidural adhesion after laminectomy more efficiently than subcutaneous fat tissue (SFT) transplantation. SUMMARY OF BACKGROUND DATA: Epidural adhesion is almost inevitable after laminectomy. Although many materials have been used to prevent adhesion, none has been widely accepted. As EFT is an ectopic fat tissue located on the dura mater and there is no adhesion between EFT and the dura mater, we focused on the efficacy of EFT for adhesion prevention. METHODS: We examined the differences in histology and gene expression between EFT and SFT of mice. We performed laminectomy at the 10th thoracic level and immediately transplanted EFT or SFT to the dura mater in mice. At 6 weeks after transplantation, we performed histological and gene expression analyses and evaluated the adhesion tenacity. In addition, we examined the characteristic differences between human EFT and SFT. RESULTS: The adipocytes of EFT were significantly smaller than those of SFT in mice and humans. The gene expression of inflammatory cytokine and fibrosis-related factors was significantly higher in SFT than in EFT. At 6 weeks after transplantation, the percentage of the remaining fat area over the dura mater was significantly greater in the EFT group than in SFT group, and the adhesion tenacity score was significantly lower in the EFT group than that in the SFT group. An RNA sequencing analysis revealed 1921 differentially expressed genes (DEGs) between human EFT and SFT, and a Gene Ontology term associated with the inflammatory response was most highly enriched in SFT. CONCLUSION: EFT has different molecular and histological profiles from SFT and EFT grafting is more effective for epidural adhesion prevention than conventional SFT transplantation after laminectomy in a mouse model.Level of Evidence: N/A.

Anterior epidural carbon dioxide dissection during spine cryoablation.

PURPOSE: Spine cryoablation (SC) of posterior vertebral lesions exposes to neuronal damages and incomplete treatment due to the proximity of the spinal canal. Carbon dioxide (CO2) dissection is a nerve protective method that can be used during spine cryoablation that tends to distribute in non-dependent areas. The purpose of this technical note was to expose the feasibility of anterior epidural CO2 dissection during SC in prone decubitus. MATERIALS AND METHODS: Three consecutives patients underwent SC of metastases abutting the posterior wall of the vertebra with anterior epidural CO2 dissection. A post-ablation MRI was performed after each cryoablation to state if the treatment was complete or incomplete. Complications were reported using the Common Terminology Criteria for Adverse Events v5.0 (CTCAE). RESULTS: Peri-procedural anterior epidural injection of CO2 was successful in all 3 procedures. Treatment was considered complete on all post-ablation MRI with ablation margins encompassing the targeted metastasis. No complication according to the CTCAE was reported. CONCLUSION: CO2 dissection of the anterior epidural space was successful in all 3 procedures allowing complete treatment on all post-ablation MRI.

Microsurgical treatment of symptomatic spinal extradural arachnoid cyst: a consecutive case series of 34 patients and literature review.

PURPOSE: A spinal extradural arachnoid cyst (SEAC) is a rare condition with unclear etiology. Herein, we report a series of symptomatic SEACs to illustrate features of SEACs in adults, surgical management, and outcomes. METHODS: A total of 34 consecutive patients who underwent microsurgical treatment were retrospectively reviewed. Patient characteristics were recorded in each case, including presenting symptoms, imaging findings, neurologic status, a surgical procedure performed and follow-up. RESULTS: There were 19 (56%) male and 15 (44%) female patients, with the ages ranging from 16 to 71 years (average 45 years). The lesions were located in the cervical segment (n = 4, 12%), thoracic segment (n = 6, 18%), thoracolumbar segment (n = 10, 29%) and lumbar segment (n = 14, 41%). Clinical presentations included back pain (n = 18, 53%), sensory deficits (n = 14, 41%), weakness (n = 4, 12%) and gait ataxia (n = 4, 12%), with a mean duration of symptoms of 17 months. The lesion was hypointense with the spinal cord on T1-weighted images and hyperintense on T2-weighted images and showed no homogeneous enhancement after contrast medium injection. Communication between the cyst and subarachnoid space was found in 23 patients and the cyst was resected after fistula ligation. Postoperatively, patients were followed up for an average of 80 months. The patients' symptoms dramatically improved and follow-up radiological images showed a complete disappearance of the cyst in all patients. No recurrence was observed in the dural repair group. CONCLUSION: Patients with symptomatic SEAC present with obvious and persistent symptoms. Complete microsurgical cyst removal with the closure of the dural defect is the standard treatment procedure with good results and a low recurrence rate.

Combined Spinal-Epidural Anesthesia for Subtotal Colectomy in a Patient With Hamman Syndrome and Epidural Pneumatosis: A Case Report.

It remains unclear how epidural pneumatosis affects the efficacy of neuraxial anesthesia. Spontaneous pneumomediastinum (Hamman syndrome) with epidural pneumatosis is rare. Regardless of its etiology, general anesthesia with positive pressure ventilation in patients with pneumomediastinum carries the risk of pneumothorax. We present a 19-year-old patient with Hamman syndrome and epidural pneumatosis who required emergency laparotomy. Effective analgesia was obtained using neuraxial anesthesia with a combined spinal-epidural anesthesia technique.

IFN-α-2b Inhibits the Proliferation and Migration of Fibroblasts via the TGFß/Smad Signaling Pathway to Reduce Postoperative Epidural Fibrosis.

Epidural fibrosis after lumbar laminectomy refers to a serious complication, and excessive proliferation of fibroblasts is considered the major factor. Interferon-alpha-2b (IFN-α-2b) can exert antiviral and antiproliferative effects, which has been suggested to effectively prevent several fibrotic diseases. However, the effect of IFN-α-2b on the prevention of epidural fibrosis (EF) and its possible mechanism remain unclear. In this study, in vitro and in vivo experiments were performed to examine the possible mechanism of IFN-α-2b for preventing EF. Cell counting kit-8 (CCK-8), cell cycle test, Edu incorporation, wound healing assay, transwell test, and Western blotting assay were performed to investigate the inhibitory effect of IFN-α-2b on the proliferation and migration of fibroblasts in vitro. As indicated from the results, IFN-α-2b was capable of inhibiting proliferation and migration of fibroblasts and inhibiting the activity of the transforming growth factor ß (TGFß)/Smad signaling pathway. In vivo, the effect of IFN-α-2b on the reduction of EF was determined by performing histological macroscopic evaluation and histological and immunohistochemical staining. As suggested from the results, IFN-α-2b significantly inhibited EF after laminectomy. As revealed from the mentioned results, IFN-α-2b may have a promising application for preventing EF in the future.

Percutaneous and Endoscopic Adhesiolysis.

Low back and leg pain may be due to many causes including scarring in the epidural space. Scar tissue often causes irritated swollen and inflamed nerves, which can cause pain. Adhesiolysis eliminate the pain-causing effects of scar tissue by releasing or decompression of a nerve from scar tissue. Percutaneous adhesiolysis is a safe and effective procedure, while epiduroscopy is a minimally invasive technique that offers diagnostic and therapeutic advantages in cases of chronic low back pain and radiculopathy. The aim of this review is to describe the comparison of percutaneous and endoscopic procedures in the lysis of adhesions in epidural fibrosis in terms of indications, contraindications, complications, technique and efficacy..

Immediate postoperative MRI findings after lumbar decompression surgery: Correlation of imaging features with clinical outcome.

An understanding of the common MRI findings observed after decompression surgery is important. However, to date, no study addressing this has been published. The aim of this study was to analyze and describe the immediate postoperative MRI findings after lumbar decompression surgery. We retrospectively analyzed the immediate postoperative MRIs of 121 consecutive patients who underwent lumbar decompression surgery between July 2017 and June 2018. Changes in stenosis at the decompressed and adjacent levels, epidural fat edema, epidural and subdural fluid collections, nerve root swelling, facet joint effusions, intervertebral disc signal, and paravertebral muscle edema were correlated with clinical characteristics. Both groups had reduced central canal stenosis postoperatively (p < 0.001) but worsened stenosis at adjacent segments. Fluid collection, hemorrhagic or non-hemorrhagic, at the laminectomy site was the commonest finding (one-level: 73.8%, two-level: 88.5%), with a higher percentage of severe central canal compromise in the two-level decompression group (p = 0.003). Other postoperative MRI findings, such as epidural fat edema, nerve root swelling, subdural fluid collection, and facet joint effusion, were noted without statistical significance. In conclusion, even with successful decompression for lumbar canal stenosis, increased central canal stenosis at adjacent segments is common on immediate postoperative MRI scans, showing no statistically significant correlation with the immediate postoperative outcome. Postoperative fluid collection at the laminectomy site is the commonest imaging finding, and higher rates of hemorrhagic fluid and more severe central canal compromise occur in two-level decompression, but rarely cause clinical problems.

[Minimally invasive treatment of cervical1-2 epidural neurilemmoma].

OBJECTIVE: To explore the minimally invasive surgical method for cervical1-2 epidural neurilemmoma. METHODS: The clinical features, imaging characteristics and surgical methods of 63 cases of cervical1-2 epidural neurilemmoma from July 2010 to December 2018 were reviewed and analyzed. Pain and numbness in occipitocervical region were the common clinical symptoms. There were 58 cases with pain, 30 cases with numbness, 3 cases with limb weakness and 2 cases with asymptomatic mass. Magnetic resonance imaging (MRI) showed that the tumors located in the cervical1-2 epidural space with diameter of 1-3 cm. The equal or slightly lower T1 and equal or slightly higher T2 signals were found on MRI. The tumors had obvious enhancement. Individualized laminotomy was performed according to the location and size of the tumors, and axis spinous processes were preserved as far as possible. Resection of tumor was performed strictly within the capsule. RESULTS: Total and subtotal resection of tumor were achieved in 60 and 3 cases respectively, and no vertebral artery injury was found. The operation time ranged from 60 to 180 minutes, with an average of 92.83 minutes. The hospitalization time ranged from 3 to 9 days, with an average of 5.97 days. All tumors were confirmed as neurilemmoma by pathology. There was no postoperative infection or cerebrospinal fluid leakage. There was no new-onset dysfunction except 9 cases of numbness in the nerve innervation area. The period of follow-up ranged from 6 months to 8 years (median: 3 years). All the new-onset dysfunction recovered completely. Pain disappeared in all of the 58 patients with pain. Numbness recovered completely in 27 patients while slight numbness remained in another 3 patients. Three patients with muscle weakness recovered completely. The spinal function of all the patients restored to McCormick grade Ⅰ. No recurrence was found on MRI. No cervical spine instability or deformity was found on X-rays. CONCLUSION: It is feasible to resect cervical1-2 epidural neurilemmoma by full use of the anatomical space between atlas and axis and individual laminotomy. It is helpful to prevent cervical instability or deformity by minimizing the destruction of cervical2 bone and preserving normal muscle attachment to cervical2 spinous process. Strict intracapsular resection can effectively prevent vertebral artery injury.

Epidural blood patch to treat a postsurgical cerebrospinal fluid leak using central line kit.

Epidural blood patches are considered definitive treatment for postdural puncture headache in adult patients. However, they are infrequently used in children or in patients with altered spine anatomy. In patients who have undergone recent spine surgery, the lumbar epidural space can be approached safely via the caudal canal. Our case demonstrates a novel technique to perform an epidural blood patch from a caudal approach using a commonly available central line kit for a 15-year-old patient with severe spinal headache due to cerebrospinal fluid leak following a hemilaminectomy.

Lay abstract An epidural blood patch is an injection of the patient's own blood into their back in the epidural space, which is the definitive treatment for headaches as a result of spinal fluid leakage. However, they are infrequently used and difficult to perform in children or in patients who have had prior back surgeries. In patients who have undergone recent spine surgery, their back-epidural space can be approached safely through caudal canal near the tailbone. Our case demonstrates a novel technique to perform an epidural blood patch from a caudal approach using a commonly available central line kit in a 15-year-old patient with severe spinal headache due to cerebrospinal fluid leak after a back surgery.

Endoscopic Subtemporal Epidural Key-Hole Approach: Quantitative Anatomic Analysis of Three Surgical Corridors.

BACKGROUND: The endoscope-assisted subtemporal key-hole epidural approach (ESKEA) has been recently described. The aim of this study was to measure working volumes and exposure of key areas of the middle cranial fossa provided by this approach. METHODS: Four fresh frozen cadaver heads were dissected to analyze 3 modular corridors (1A, 1B, and 2) harvested through ESKEA. A step-by-step dissection was performed, and key anatomic landmarks were recorded. A GTxEyesII-ApproachViewer was used to quantify the working volume and exposure of 4 different regions (sphenoorbital, parasellar, superior petrous apex, and squamopetrous). For each corridor, 3 incremental degrees of temporal dural retraction (5, 10, and 15 mm) were tested. RESULTS: The working volume of all corridors progressively increased with degree of retraction: Corridors 1A, 1B, and 2 showed a gain in working volume of 21%, 27%, and 19% from 5 mm to 10 mm retraction, respectively, and a gain of 40%, 45%, and 44% from 5 mm to 15 mm retraction, respectively. The sphenoorbital area was exposed (27%-45%) through corridor 1A, and exposure significantly increased with the degree of retraction. Corridor 1B provided optimal exposure of parasellar areas (86%-100%) and superior petrous apex (70%-87%) regardless of the degree of retraction. The squamopetrous area was satisfactorily addressed through corridor 2 (88%) only with the highest degree of retraction. CONCLUSIONS: ESKEA can be conceived as a modular approach: the 3 surgical corridors have specific working volumes, which are clearly influenced by the degree of temporal lobe retraction, and provide exposure of different middle cranial fossa areas.

Polypropylene mesh inhibits post-laminectomy compressive scar formation in rabbits: Histopathological and computational morphometric evaluation.

We evaluated the effect of polypropylene mesh placement on post-laminectomy compressive scar formation in rabbits. Twenty-two white male New Zealand rabbits were distributed into two groups (n = 11). In the control group, the animals underwent lumbosacral laminectomy, whereas in the mesh group, the rabbits were submitted to lumbosacral laminectomy followed by the attachment of a polypropylene mesh to the vertebrae by the application of N-butyl cyanoacrylate. After eight weeks, the rabbits were euthanized, and the laminectomy area was collected for macro- and microscopic analyses. Macroscopically, we evaluated the (1) vertebral canal height; (2) laminectomy width and (3) length; and (4) fibrosis width, (5) height, and (6) length. Microscopically, we evaluated (7) fibroblasts; (8) the thickness of the dura-mater; and (9) the distance between the dura-mater and the laminectomy area. Macroscopically, there were no differences between the groups regarding vertebral canal height; width and length of the laminectomy; and fibrosis width. However, the height, and length of fibrosis were smaller in the mesh group. Microscopically, there were no differences in dura mater thickness and the distance between the dura mater and laminectomy area, but fewer fibroblasts were observed in the mesh group. This indicated that the polypropylene mesh improved tissue repair, with greater tissue organization. The results demonstrate that the use of a polypropylene mesh in the treatment of post-laminectomy wounds in rabbits reduces the severity of compressive fibrous scar formation. Polypropylene mesh is presented as a good alternative to reduce complications associated with laminectomy surgeries.

Alternative Technique for Difficult Epidural Needle Placement: A Case Report.

A central neuraxial block may be difficult to perform in elderly patients with lumbar spine deformities, calcified ligaments, and narrowing of the epidural space. We report a case of difficult epidural needle placement in an elderly patient scheduled for bilateral total knee replacement (TKR). We attempted epidural needle placement many times without success. However, when a modified technique was used, the epidural space was identified easily and confirmed, the epidural catheter was inserted and fixed, and the postoperative epidural analgesia was effective.