Dural repair using autologous fat: Our experience and review of the literature

Fat in the brain: Facts and features

The presence of fat within a lesion in the brain is not only easy to identify on both CT/MRI but also can help narrow the differential. The purpose of this paper is to illustrate the spectrum of common and rare fat-containing lesions in the brain that are encountered in clinical practice. This paper intends to discuss 15 such lesions which are confirmed by MRI findings and histopathological correlation. We divided the spectrum of fat-containing lesions into lesions with adipose cells, lesions with cholesterol-rich content and tumours with lipomatous differentiation/transformation. Knowledge of these common and rare fat-containing lesions is essential for making the right diagnosis or narrowing the differential diagnosis.

Cauda equina syndrome caused by the application of DuraSealTM in a microlaminectomy surgery: A case report

BACKGROUND

The management of dural tears is important. While a massive dura can be repaired with absorbable suture lines, cerebrospinal fluid leakage can be attenuated by dural sealant when an unintended tiny durotomy occurs intraoperatively. DuraSeal is often used because it can expand to seal tears. This case emphasizes the need for caution when DuraSeal is used as high expansion can cause complications following microlaminectomy.

CASE SUMMARY

A 77-year-old woman presented with L2/3 and L3/4 lateral recess stenosis. She underwent microlaminectomy, foraminal decompression, and disk height restoration using an IntraSPINE^® device. A tiny incident durotomy occurred intraoperatively and was sealed using DuraSeal^TM. However, decreased muscle power, urinary incontinence, and absence of anal reflexes were observed postoperatively. Emergent magnetic resonance imaging revealed fluid collection causing thecal sac indentation and central canal compression. Surgical exploration revealed that the gel-like DuraSeal had entrapped the hematoma and, consequently, compressed the thecal sac and nerve roots. While we removed all DuraSeal^TM and exposed the nerve root, the patient’s neurological function did not recover postoperatively.

CONCLUSION

DuraSeal expansion must not be underestimated. Changes in neurological status require investigation for cauda equina syndrome due to expansion.

Imaging of intracranial fat: from normal findings to pathology

The presence of intracranial adipose tissue is often overlooked, although it may be detected in different physiological (dural sinuses or falx deposition of fat) and pathological (lipoma, dermoid cyst, subarachnoid fat dissemination) conditions. In this review, we illustrate various scenarios in which radiologists and neuroradiologists may encounter intracranial fat, providing a list of differential diagnosis.

Effectiveness of Repair Techniques for Spinal Dural Tears: A Systematic Review

BACKGROUND

Incidental or intentional durotomy in spine surgery is associated with a risk of cerebrospinal fluid (CSF) leakage and reoperation. Several strategies have been introduced, but the incomplete closure is still relatively frequent and troublesome. In this study, we review current evidence on spinal dural repair strategies and evaluate their efficacy.

METHODS

PubMed, Web of Science, and Scopus were used to search primary studies about the repair of the spinal dura with different techniques. Of 265 articles found, 11 studies, which specified repair techniques and postoperative outcomes, were included for qualitative and quantitative analysis. The primary outcomes were CSF leakage and postoperative infection.

RESULTS

The outcomes of different dural repair techniques were available in 776 cases. Pooled analysis of 11 studies demonstrated that the most commonly used technique was a combination of primary closure, patch or graft, and sealant (22.7%, 176/776). A combination of primary closure and patch or graft resulted in the lowest rate of CSF leakage (5.5%, 7/128). In this study, sealants as an adjunct to primary closure (13.7%, 18/131) did not significantly reduce the rate of CSF leakage compared with primary closure alone (17.6%, 18/102). The rates of infection and postoperative neurologic deficit were similar regardless of the repair techniques.

CONCLUSIONS

Although the use of sealants has become prevalent, available sealants as an adjunct to primary closure did not reduce the rate of CSF leakage compared with primary closure. The combination of primary closure and patches or grafts could be effective in decreasing postoperative CSF leakage.

Cerebrospinal Fluid Leaks and Pseudomeningocele after Posterior Fossa Surgery: Effect of an Autospray Dural Sealant

Background

Posterior fossa craniotomies can be complicated by cerebrospinal fluid (CSF) leaks, infection, meningitis, neurologic deficits, and intracranial hypotension caused by defective closure of the dura. Secondary dural closures such as pericranial graft, muscle graft, glue, sealants, or fat graft are used. However, there have been few studies examining the use of sealants with a polyethylene glycol and polyethylenimine component.

Objective

We studied the effect of one such sealant, Adherus® (HyperBranch Medical Technology, Durham, NC, USA), as an adjunct to secondary closure methods in the reduction of the use of abdominal fat grafting and lumbar puncture/drains.

Methods

We retrospectively reviewed the surgical records of all patients undergoing posterior fossa cranial surgery during a two-year period at a tertiary university affiliated medical center.

Results

Overall, data a total of 122 patients (62 in the no Adherus and 60 in the Adherus group) were collected. There was no statistically significant difference in the 30-day incisional CSF leak rate (4.1% vs. 6.5%; p=0.183), 30-day non-incisional CSF leak rate (11.3% vs. 5.0%; p=0.205), and 30-day pseudomeningocele rate (16.1% vs. 13.3%; p=0.663) in the no Adherus and Adherus groups, respectively. However, there was a significant reduction in the use of abdominal fat grafting (0% vs. 30.7%; p<0.001) and intraoperative CSF diversion techniques (58.1% vs. 23.3%; p<0.001). Every instance of the use of Adherus saved on average, $809.36.

Conclusions

A statistically significant reduction in the use of CSF shunting procedures during posterior fossa craniotomy/craniectomy was achieved after the introduction of Adherus with no increase in CSF leak rate.

[Liquorrhea after removal of fourth ventricle tumors in children. Retrospective analysis of a series of 211 primary surgeries]

Wound liquorrhea is a serious and dangerous complication developing after neurosurgical interventions. The highest risk group includes patients operated on using approaches to the skull base. In pediatric neurosurgery, approaches to the posterior cranial fossa are some of the most common ones, with wound liquorrhea amounting to 33%. Studies devoted to the wound liquorrhea problem have been performed in heterogeneous patient groups, which complicates evaluation of the results and reduces their practical value.

MATERIAL AND METHODS

The analysis included pediatric patients operated on by a single surgeon for posterior cranial fossa (PCF) tumors in the period from 2009 to 2016. There were 472 patients. Criteria for inclusion in the study were as follows: age under 18 years; predominant tumor location in the fourth ventricle; primary surgery. According to the inclusion criteria, the study involved 211 patients. A search for the key words 'liquorrhea', 'pooling', 'meningocele', 'pseudomeningocele', and 'meningitis' was performed through electronic medical records of the involved patients. We analyzed the data on the total bed-day and the number of days spent in the critical care unit. Surgery protocols were the source of the following information: the presence of an external ventricular drain or ventriculoperitoneal shunt before tumor resection; information on DM closure; information on additional sealing of dura sutures. In addition, the patients were divided into two groups, the main difference between which was the use of additional sealing of dura sutures (Tachocomb, fibrin-thrombin glues, and their combination) to minimize the risk of wound liquorrhea.

RESULTS

A total of 211 patients were included in the study. Postoperative wound liquorrhea occurred in 6 (2.8%) patients; another 5 (2.4%) patients had significant pseudomeningocele. Most children spent no more than 1 day in the critical care unit - totally 176 (83.4%) patients; the other 35 (16.6%) children spent more than 1 day in the critical care unit. A group of patients without sealing of dura sutures consisted of 144 (68.2%) patients. Liquorrhea occurred in 4 (2.8%) cases; in 3 (2.1%) cases, there was symptomatic pseudomeningocele without liquorrhea. In a group of patients with the use of suture sealing (Tachocomb, fibrin-thrombin glue in various combinations - 67 (31.8%) patients), there was liquorrhea in 2 (3%) cases and pseudomeningocele without liquorrhea in 2 (3%) cases. On the basis of PSM algorithm application, 2 groups of 67 patients each were formed: the group with sealing (A) and the group without sealing (B) of the DM. Of the 67 cases of sealing, Tachocomb was used in 64 (95.5%) patients, and fibrin-thrombin glue was applied in 53 (59.1%) patients. Differences between the groups in the rate of liquorrhea (2 (3.0%) patients in group A and 4 (6.0%) patients in group B) and pseudomenigocele (3 (4.5%) patients in group A and 5 (7.5%) patients in group B) were statistically insignificant (p=0.68 and p=0.58, respectively).

CONCLUSION

Wound liquorrhea has remained a topical issue in surgery for posterior cranial fossa tumors and, if develops, doubles the postoperative bed-day. Our strategy of perioperative management of patients proved its efficacy in reducing the rate of postoperative liquorrhea up to 2.8%. A low percentage of liquorrhea did not allow unambiguous evaluation of the effect of additional sealing of dura sutures (Tachocomb and fibrin-thrombin glue).

A Stable Large Animal Model for Dural Defect Repair with Biomaterials and Regenerative Medicine

IMPACT STATEMENT

Using biomaterials and regenerative medicine to repair tissue defects has been a very hot research field, during which the development of stable large animal models with appropriate biotechnology is crucial. Recently, more and more researchers are paying attention to dural defect repair. However, the lack of widely recognized stable large animal models has seriously affected the related further research. In this study, a stable large animal dural defect model is developed exactly for the first time. Therefore, the article would attract considerable attention and be highly cited after publication.

Generation of Functional Human Adipose Tissue in Mice from Primed Progenitor Cells

Adipose tissue (AT) is used extensively in reconstructive and regenerative therapies, but transplanted fat often undergoes cell death, leading to inflammation, calcification, and requirement for further revision surgery. Previously, we have found that mesenchymal progenitor cells within human AT can proliferate in three-dimensional culture under proangiogenic conditions. These cells (primed ADipose progenitor cells, PADS) robustly differentiate into adipocytes in vitro (ad-PADS). The goal of this study is to determine whether ad-PADS can form structured AT in vivo, with potential for use in surgical applications. Grafts formed from ad-PADS were compared to grafts formed from AT obtained by liposuction after implantation into nude mice. Graft volume was measured by microcomputed tomography scanning, and the functionality of cells within the graft was assessed by quantifying circulating human adiponectin. The degree of graft vascularization by donor or host vessels and the content of human or mouse adipocytes within the graft were measured using species-specific endothelial and adipocyte-specific quantitative real time polymerase chain reaction probes, and histochemistry with mouse and human-specific lectins. Our results show that ad-PADS grafted subcutaneously into nude mice induce robust vascularization from the host, continue to increase in volume over time, express the human adipocyte marker PLIN1 at levels comparable to human AT, and secrete increasing amounts of human adiponectin into the mouse circulation. In contrast, grafts composed of AT fragments obtained by liposuction become less vascularized, develop regions of calcification and decreased content of PLIN1, and secrete lower amounts of adiponectin per unit volume. Enrichment of liposuction tissue with ad-PADS improves vascularization, indicating that ad-PADS may be proangiogenic. Mechanistically, ad-PADS express an extracellular matrix gene signature that includes elements previously associated with small vessel development (COL4A1). Thus, through the formation of a proangiogenic environment, ad-PADS can form functional AT with capacity for long-term survival, and can potentially be used to improve outcomes in reconstructive and regenerative medicine.

[Tactics of reconstructive closure of basal defects after resection of midline tumors of the anterior skull base (a literature review)]

The purpose of this review is to analyze the techniques used to reconstruct midline defects in the anterior skull base after transcranial and endoscopic endonasal resection of skull base tumors. We provide brief information on the technique for preparing various flaps, indications and contraindications, and advantages and disadvantages. We analyze the international experience in the use of vascularized and non-vascularized flaps as well as the existing algorithms for reconstruction of complex defects of the midline structures of the skull base. The literature data demonstrate the absence of a conventional tactics of reconstructive closure of the discussed defects. To resolve this issue, a meta-analysis in combination with an original prospective study is required.

Parasagittal meningiomas: Our surgical experience and the reconstruction technique of the superior sagittal sinus

Background:

The radical resection of parasagittal meningiomas without complications and recurrences is the goal of the neurosurgeon. Nowadays, different managements are proposed. This study describes our surgical technique during the lesional excision and the reconstruction of the superior sagittal sinus (SSS).

Methods:

The total removal (Simpson I and II) of parasagittal meningiomas (WHO grade I and II) was obtained in 75 patients from September 2000 to January 2010. The indocyanine green videoangiography was used before the dural opening and, when necessary, to identify and preserve the cortical veins. The surgery of the SSS was performed in accordance with Sindou's classification, and its reconstruction was achieved through the use of a patch of galea capitis.

Results:

We had no cases of recurrence and thrombotic occlusion of the SSS in 5 years after the reconstruction. No complications were observed in 65 patients, and no cases of mortality were reported. Neurological focal deficits were observed in 5 patients. A brain swelling and a venous infarction were observed in 1 patient. Only one case of thrombotic occlusion was observed. A cerebrospinal fluid leak was observed in 2 patients, and a systemic complication was found in 1 patient.

Conclusion:

Several factors contribute to the success of the parasagittal meningioma surgery. We consider the preservation of the cortical veins to be important, and, when possible, we recommend the reconstruction of the anterior third of the SSS. Our experience has led us to believe that until now surgery is a winning choice if practiced by expert hands.