The safety and effectiveness of a dural sealant system for use with nonautologous duraplasty materials

Differential efficacy with epidural blood and fibrin patches for the treatment of post-dural puncture headache

BACKGROUND

Accidental dural puncture (ADP) is the most frequent major complication when performing an epidural procedure in obstetrics. Consequently, loss of pressure in the cerebrospinal fluid (CSF) leads to the development of post-dural puncture headache (PDPH), which occurs in 16%-86% of cases. To date, the efficacy of epidural fibrin patches (EFP) has not been evaluated in a controlled clinical trial, nor in comparative studies with epidural blood patches (EBP).

METHODS

The objective of the present study was to compare the efficacy of EFP with respect to EBP for the treatment of refractory accidental PDPH. This prospective, randomized, open-label, parallel, comparative study included 70 puerperal women who received an EBP or EFP (35 in each group) after failure of the conventional analgesic treatment for accidental PDPH in a hospital.

RESULTS

A higher percentage of women with EFP than EBP achieved complete PDPH relief after 2 (97.1% vs. 54.3%) and 12 h (100.0% vs. 65.7%) of the patch injection. The percentage of patients who needed rescue analgesia was significantly lower with EFP after 2 (2.9% vs. 48.6%) and 12 h (0.0% vs. 37.1%). After 24 h, PDPH was resolved in all women who received EFP. The recurrence of PDPH was reported in one woman from the EBP group (2.9%), who subsequently required a second patch. The mean length of hospital stay was significantly lower with EFP (3.9 days) than EBP (5.9 days). Regarding satisfaction, the mean value (Likert scale) was significantly higher with EFP (4.7 vs. 3.0).

CONCLUSIONS

EFP provided better outcomes than EBP for the treatment of obstetric PDPH in terms of efficacy, safety, and patient satisfaction.

The comparison of the watertight and non-watertight dural closure in supratentorial craniotomy: A single-institute 10-year experience with 698 patients

Watertight dural closure (WTDC) is considered crucial by many neurosurgeons in cranial base surgery, infratentorial craniotomy, and spinal intradural procedure. Whether WTDC also reduce complications remains controversial in supratentorial craniotomy. The objective of this study is to investigate the relationship between WTDC and CSF-related complications in supratentorial craniotomy for the resection of space-occupying lesions. A retrospective analysis of patients who suffered from intracranial space-occupying lesions at Beijing Ditan Hospital between January 2011 and December 2021 was conducted. A total of 698 cases were reviewed with attention to the operative approach, subgaleal fluid collection, wound healing impairment, postoperative infection, and post-craniotomy headaches. The study included a total of 423 patients with WTDC and 275 patients without WTDC. Patients without WTDC had a significantly higher rate of infection (10.9% vs 4.5% with WTDC, P = .001). The rate of subgaleal fluid collection was 9.7% in the WTDC group and 11.3% in the non-WTDC group, but this difference was not statistically significant (P = .502). They suffered from a greater incidence of post-craniotomy headaches in the WTDC group (13.5% vs 9.5% in the non-WTDC group), but without statistical significance (P = .109). We also found no difference in wound healing impairment (P = .719). There is less postoperative infection associated with WTDC during intracranial space-occupying lesion removal than without WTDC in supratentorial craniotomy.

Surgical nuances and placement of subgaleal drains for supratentorial procedures-a prospective analysis of efficacy and outcome in 150 craniotomies

Background

For supratentorial craniotomy, surgical access, and closure technique, including placement of subgaleal drains, may vary considerably. The influence of surgical nuances on postoperative complications such as cerebrospinal fluid leakage or impaired wound healing overall remains largely unclear. With this study, we are reporting our experiences and the impact of our clinical routines on outcome in a prospectively collected data set.

Method

We prospectively observed 150 consecutive patients undergoing supratentorial craniotomy and recorded technical variables (type/length of incision, size of craniotomy, technique of dural and skin closure, type of dressing, and placement of subgaleal drains). Outcome variables (subgaleal hematoma/CSF collection, periorbital edema, impairment of wound healing, infection, and need for operative revision) were recorded at time of discharge and at late follow-up.

Results

Early subgaleal fluid collection was observed in 36.7% (2.8% at the late follow-up), and impaired wound healing was recorded in 3.3% of all cases, with an overall need for operative revision of 6.7%. Neither usage of dural sealants, lack of watertight dural closure, and presence of subgaleal drains, nor type of skin closure or dressing influenced outcome. Curved incisions, larger craniotomy, and tumor size, however, were associated with an increase in early CSF or hematoma collection (p < 0.0001, p = 0.001, p < 0.01 resp.), and larger craniotomy size was associated with longer persistence of subgaleal fluid collections (p < 0.05).

Conclusions

Based on our setting, individual surgical nuances such as the type of dural closure and the use of subgaleal drains resulted in a comparable complication rate and outcome. Subgaleal fluid collections were frequently observed after supratentorial procedures, irrespective of the closing technique employed, and resolve spontaneously in the majority of cases without significant sequelae. Our results are limited due to the observational nature in our single-center study and need to be validated by supportive prospective randomized design.

Electronic supplementary material

The online version of this article (10.1007/s00701-019-04196-6) contains supplementary material, which is available to authorized users.

Failure Pressures of Dural Repairs in a Porcine Ex Vivo Model: Novel Use of Titanium Clips Versus Tissue Glue

Objective

Endoscopic skull base surgery is advancing, and it is important to have reliable methods to repair the resulting defect. The objective of this study was to determine the failure pressures of 2 commonly used methods to repair large dural defects: collagen matrix underlay with fibrin glue and collagen matrix underlay with polyethylene glue, as well as a novel repair method: fascia lata with nonpenetrating titanium vascular clips.

Methods

The failure pressure of the 3 dural repairs was determined in a closed testing apparatus. Defects in porcine dura were created and collagen matrix grafts were used as an underlay followed by either fibrin glue (FG/CMG) or polyethylene glycol glue (PEG/CMG). A third condition using a segment of fascia lata was positioned flush with the edges of the dural defect and secured with titanium clips (TC/FL). Saline was infused to simulate increasing intracranial pressure (ICP) applied to the undersurface of the grafts until the repairs failed.

Results

The mean failure pressure of the PEG/CMG repair was 34.506 ± 14.822 cm H₂O, FG/CMG was 12.413 ± 5.114 cm H₂O, and TC/FL was 8.330 ± 3.483 cm H₂O. There were statistically significant differences in mean failure pressures among the 3 repair methods.

Conclusion

In this ex vivo model comparing skull base repairs’ ability to withstand cerebrospinal fluid leak, the repairs that utilized PEG/CMG tolerated the greatest amount of pressure and was the only repair that exceeded normal physiologic ICP’s. Repair methods utilizing glues generally tolerated higher pressures compared to the novel repair using clips alone.

Comparison of dural closure alternatives: an experimental study

Introduction: Dural closure preference has been a topic of debate in contemporary neurosurgery. This study aims to compare different closure techniques using an in vitro model.Methods: Human cadaveric dura mater was attached to a cylindrical metal glass filled with blue dyed saline. A 1 cm dural incision was made. Dural closure was performed using three different techniques. Each group had six samples: Group I - interrupted simple 4-0 polyglactin suture (S) only, Group II - S plus on lay collagen graft, Group III - S plus fibrin sealant. In Group NS, a 1 cm × 1 cm dural window was made. An onlay collagen graft was used with no suturing for this group to serve as an overtly weak reconstruction reference. Primary and secondary leak pressures were recorded (PLP and SLP, respectively).Results: All groups (I-III) had significantly higher PLP and SLP than Group NS. PLP was significantly higher in Group III as compared to groups I and II. Groups I and II had similar PLP values. SLP was similar in all three groups.Conclusion: In this study, the use of fibrin sealant has proven to be the best option in preventing dural leak. However, no technique was superior in the case of SLP.

Safety and Efficacy of a Novel, Self-Adhering Dural Substitute in a Canine Supratentorial Durotomy Model

BACKGROUND

Cerebrospinal fluid (CSF) leaks increase postoperative risk for complication, likelihood of reoperation, and costs.

OBJECTIVE

To investigate a novel, self-adhering polyethylene glycol-coated collagen pad (PCC) as a dural substitute relative to Duragen XS (DGX; Integra LifeSciences Corporation, Plainsboro, New Jersey) and as a dural sealant relative to Tachosil (Takeda Austria GmbH, Linz, Austria), a fibrinogen and thrombin-coated collagen pad (FTC).

METHODS

A canine supratentorial durotomy surgical model was used to investigate the safety and efficacy of PCC. For safety, 4 animals were bilaterally treated with DGX or PCC and recovered for 1, 8, or 16 wk; total 24 animals. Each animal underwent physical and neurological examinations weekly and 16-wk animals underwent a magnetic resonance imaging (MRI) examination at each time point. For efficacy, 9 animals were unilaterally treated with FTC or PCC and underwent a burst pressure test intraoperatively or 14 d postoperatively; total 36 animals.

RESULTS

In the safety study, no abnormal clinical signs or changes were noted on physical and neurological examinations, or in clinical pathology, CSF analysis or histopathology of DGX or PCC-treated animals. No consistent signs of cerebral compression, CSF leak, hemorrhage, or hydrocephalus were noted on MRI. In the efficacy study, no significant difference was found between FTC and PCC at each time point or overall (13.9 vs 12.3 mm Hg, n = 18 per group, P = .46).

CONCLUSION

PCC is safe for use as a dural substitute and effective as a dural sealant. The novel, self-adhering combination of a polyethylene glycol-based sealant and a collagen pad may offer unique benefits to the advancement of duraplasty.

Visualized ethmoid roof cerebrospinal fluid leak during frontal balloon sinuplasty

Balloon sinus dilation (BSD) is generally accepted as a safe alternative to traditional sinus surgery. It is a unique technique designed to potentially minimize complications associated with traditional functional endoscopic sinus surgery (FESS). We present a case in which a 65-year-old man experienced a cerebrospinal fluid (CSF) leak in the ethmoid roof that was visualized instantly after balloon dilation in a revision sinus surgery. In this case report, we discuss the causes of CSF leaks and explain in detail the immediate endoscopic repair with a collagen matrix. Also, literature is reviewed on the safety of BSD versus traditional FESS. Postoperatively, the patient has been without CSF leak and remains symptom free. CSF leak is a rare but major complication during both FESS and BSD. As BSD use increases, its complication profile will become clearer when used alone, in conjunction with FESS, and/or during revision surgery. Although BSD is considered a benign procedure, one should be cautious when using it in revision sinus surgery.

Effectiveness of the Biophysical Barriers to the Peridural Fibrosis in Rat Laminectomy Model

Purpose: Peridural fibrosis which could occur after the spinal surgery could adhere neural tissue closely and may cause to neural entrapment symptoms and require surgical reintervention. Aim of the study: Present study was designed to reduce occurrence of peridural fibrosis in rat laminectomy model by using biophysical barriers called hyaluronic acid (HAS) dural barrier, activated polyethylene glycol and polyethylene imine (PEG) dural barrier, and platelet-rich plasma (PRP). Materials and methods: In this study, 2 of 26 male Wistar albino rats (325-350 g body weight), which were not included into study groups were sacrificed by removing their total blood and their blood was used for preparation of PRP, and remaining rats were randomly delivered into four groups called SHAM, HAS, PEG, and PRP groups. Then L3-4-5 laminectomy was performed to all animals and experimental agents were administered to the selected groups mentioned above. Spinal colons of all animals were removed gross total after 6-week period and investigated histopathologically. Additionally, real-time-polymerase chain reaction was used to obtain collagen type I and type III, transforming growth factor-1β, and tumor necrosis factor-α gene expressions. Results: All results demonstrated that polyethylene glycol and polyethylene imine dural barrier and PRP could decrease peridural fibrosis formation efficiently in rat. Conclusion: Present study results suggested that to reduce or block formation of peridural fibrosis, either polyethylene glycol and polyethylene imine dural barrier or PRP could be used effectively in human subjects after they will be closely investigated in future studies.

Factors Leading to a Poor Functional Outcome in Spinal Meningioma Surgery: Remarks on 173 Cases

BACKGROUND

Spinal meningiomas are common spinal tumors, in most cases benign and with a good surgical prognosis. However, specific location, infiltration of spinal cord, vascular encasement, or spinal root involvement can bring a less favorable prognosis.

OBJECTIVE

To correlate these data with clinical/functional outcome.

METHODS

Two hundred twenty-four consecutive patients with spinal meningiomas treated from 1976 to 2013 in our institution were analyzed; among these, 51 were excluded for incomplete clinical data or follow-up. The remaining 173 cases were classified in regards to sex, age, symptoms, axial location, Simpson grade resection, and functional pre-/postoperative status.

RESULTS

Most recurring onset symptoms were pain (32.9%) and motor deficit (31.8%); thoracic spine was the most severely affected (69.8%). Functional improvement on the follow-up was observed in 86.7% of cases; 6.4% of patients resulted stable and 6.9% worsened. A low functional grade before surgery was connected to a lesser improvement after. Anterolateral meningiomas were the most represented (42.2%); a gross total resection (Simpson grades I and II) was conducted in 98.8%, and a macroscopically complete removal without dural resection or coagulation (Simpson grade III) was performed in 1.2%. Of the meningiomas, 98.3% were classified as WHO grade I. Recurrence rate was 2.3%, and 7 cases presented complications (4 of 7 required surgical procedure).

CONCLUSION

We can affirm that negative prognostic factors in our study were anterior or anterolateral axial location, prolonged presentation before diagnosis, WHO grade >I, Simpson grade resections II and III, sphincter involvement, and worse functional grade at onset.

Cerebrospinal fluid leaks after transsphenoidal surgery - Effect of a polyethylene glycol hydrogel dural sealant

To investigate cerebrospinal fluid (CSF) leak rates after mainly endoscopic endonasal transsphenoidal surgery with and without polyethylene glycol hydrogel dural sealant (DuraSeal®), we prospectively collected data from a single-centre consecutive case series over four years from January 2007 to December 2010 inclusive. 250 patients were identified (135 male, 115 female; median age 52years, range 14-83). 180 patients received DuraSeal® (72%). 85 (34%) had intra-operative dural breach and 13 (5.2%) developed post-operative CSF leaks (3 without intra-operative dural breach) requiring lumbar drainage or formal repair. Of this group 5/251 (2.0%) patients required a formal repair. Post-operative CSF leak was seen in 5/189 (2.7%) of patients with pituitary adenoma, of which 2/5 (40%) were in cases undergoing revision surgery. 5/13 (38.4%) patients who developed a CSF leak presented with either Rathke's cleft cyst or craniopharyngioma. 3/71 patients not receiving DuraSeal® leaked (4.2%) and 10/180 patients receiving DuraSeal® leaked (5.6%). 11/234 patients without Tisseel (4.7%) and 2/16 receiving Tisseel (12.5%) leaked. 54 patients (22%) received intra-operative lumbar drains, one of whom developed subsequent CSF leak (1.9%), in contrast to 12/197 (6.1%) of patients without intra-operative lumbar drains who later developed CSF leak. The rate of post-operative CSF leak requiring re-exploration and nasoseptal flap repair was low (2.0%) in this mainly endoscopic case series without statistically significant benefit from either DuraSeal® or Tisseel. Intra-operative and post-operative lumbar drainage appears beneficial in patients at higher risk of post-operative CSF leak.

Spinal sealant system provides better intraoperative watertight closure than standard of care during spinal surgery: a prospective, multicenter, randomized controlled study

STUDY DESIGN

Prospective, 3:1 randomized, single-blind, multicenter investigational study.

OBJECTIVE

To assess the safety and efficacy of a low-swell spinal sealant when used as an adjunct to sutured dural repair compared with standard of care methods to obtain watertight dural closure in subjects undergoing spinal surgery.

SUMMARY OF BACKGROUND DATA

Watertight dural closure is paramount in spinal surgery to avoid complications of cerebrospinal fluid leak. Prior reports have proven the efficacy of a synthetic, absorbable polyethylene glycol (PEG) hydrogel sealant in spinal surgery compared with standard of care. Given the potential concerns of swelling in spinal applications, the hydrogel was modified to a low-swell formulation.

METHODS

The primary endpoint was success rate in obtaining intraoperative watertight dural closure in subjects receiving PEG hydrogel sealant versus a control group of subjects receiving any standard method designed to provide intraoperative watertight closure. Subjects were evaluated at discharge and at 30 and 90 days postprocedure for cerebrospinal fluid leaks, surgical site infections, and adverse events.

RESULTS

Between May 2007 and May 2009, 98 subjects (74 PEG hydrogel spinal sealant, 24 control) were randomized at 14 clinical sites in the United States. Patients treated with the PEG hydrogel spinal sealant had a significantly higher rate of watertight closure than the control (98.6% vs. 79.2%, P = 0.003). No statistical differences were seen in postoperative cerebrospinal fluid, infection, and wound healing. No neurological deficits were seen attributable to the sealant.

CONCLUSION

The low-swell PEG hydrogel spinal sealant evaluated in this study has been proven safe and effective for providing watertight closure when used as an adjunct to sutured closure of intentional durotomies during spinal surgery. PEG hydrogel sealants have again proved superior to other standard of care technologies for safe, efficacious dural closure.

LEVEL OF EVIDENCE

2.

Two alternative dural sealing techniques in posterior fossa surgery: (Polylactide-co-glycolide) self-adhesive resorbable membrane versus polyethylene glycol hydrogel

BACKGROUND

Post-operative cerebrospinal fluid (CSF) leak in posterior fossa surgery remains a significant source of morbidity. TissuePatchDural (TPD), a novel impermeable adhesive membrane, was used to reinforce dural closure. A comparison with one of the most commonly used dural sealing devices, DuraSeal, has been made.

METHODS

A retrospective, single-center study was conducted on 161 patients who underwent elective posterior fossa surgery. On surgeon's opinion, when a primary watertight closure was not possible, they received TPD or DuraSeal to reinforce dural closure.

RESULTS

Out of 161 patients analyzed, 115 were treated with TPD and 46 with DuraSeal. The post-operative leaks related purely to TPD or DuraSeal failure were recognized in 3 (2.6%) and 5 (10.86%) cases, respectively (P = 0.015). The presence of pre- and post-operative risk factors was associated with an increased incidence of CSF leak in both groups. TPD showed a better control in patients without these risk factors (P = 0.08). The incidence of CSF leak in patients who underwent posterior fossa surgery by craniectomy was statistically lower in TPD group compared to DuraSeal group (3.22% vs 17.8%, respectively; P = 0.008).

CONCLUSIONS

TPD seems to be a safe tool for use as an adjunct to standard dural closure in posterior fossa surgery, particularly in patients without pre- or post-oper ative risk factors, in those who did not develop hydrocephalus, and who underwent craniectomy. The CSF leak rate in TPD group was found to be lower or within the range of the more advanced alternative dural closure strategies, including polyethylene glycol (PEG)-based sealant.

Use of Tissue Glues in Endoscopic Pituitary Surgery: A Cost Comparison

Background:

Post-operative cerebrospinal fluid (CSF) leaks are a common complication of endoscopic pituitary surgery and account for a significant proportion of hospital costs associated with this procedure. Tisseel® is a tissue glue commonly used as an adjunct in dural repair but is not optimal for this purpose. DuraSeal® has several properties advantageous for dural repair but is not widely accepted in Canada partly due to its increased cost.

Objective:

A cost analysis of DuraSeal® versus Tisseel® in endoscopic pituitary surgery.

Methods:

A cost analysis was performed based on typical endoscopic pituitary surgery cases performed at our tertiary care institution. Operating room, hospital admission, and surgical sealant costs were obtained directly while estimates of patient recovery time and post-operative CSF leak rates were based on consensus values reported in the literature. Outcomes were reported for various possible clinical scenarios of sealant use.

Results:

In a model where surgical sealant is employed only in high-risk cases, use of DuraSeal® allows for a yearly cost savings of at least $4486.72. If surgical sealant is used in all cases, regular use of DuraSeal® versus Tisseel® either marginally reduces yearly costs or increases them by a maximum of $7619.25, depending on the case volume and estimated post-operative CSF leak rate.

Conclusion:

In most clinical scenarios, use of DuraSeal® in endoscopic pituitary surgery may reduce overall yearly hospital costs compared to Tisseel®.

Evaluation of complication rates of pediatric cranial procedures in which a polyethylene glycol sealant was used

OBJECT

Polyethylene glycol (PEG) sealant in conjunction with standard closure techniques is effective in preventing CSF leaks after cranial procedures in adult patients, but the safety of PEG sealant in the pediatric population has not been shown.

METHODS

The authors performed a retrospective analysis of pediatric neurosurgery patients (0-18 years of age) treated from 2005 to 2010 at The Johns Hopkins Hospital. There were 163 patients who underwent cranial surgery with the use of PEG sealant as an adjunct to standard closure techniques. There were 92 males and 71 females with an average age of 10.2 years. The incidences of revision surgery, CSF leak, meningitis, and neurological deficit were recorded.

RESULTS

In the cohort's 90-day postoperative clinical course, the authors found that 4 patients (2.5%) required revision surgery, 2 patients (1.2%) developed a CSF leak, 4 patients (2.5%) developed a superficial skin infection, and 1 patient developed meningitis (0.6%) with no deaths or neurological deficits observed.

CONCLUSIONS

PEG sealant appears to be a safe adjunct to standard dural closure in pediatric cranial surgery patients to augment dural closure.

[Use of hydrogel as spacer in Denovier's space: optimization of IMRT radiotherapy of localized prostate cancer]

BACKGROUND

Radiotherapy is an appropriate primary therapy for localized prostate cancer in accordance with urological guidelines. Especially in tumors of higher grade malignancy, dose escalation up to 80,0 Gy seems to be an advantage; however rectum toxicity can be a problem. By injecting a synthetic hydrogel (SpaceOAR®) as a spacer between the prostate and rectum, rectal toxicity can be reduced. We report on our experiences with 47 patients and an average follow-up of 241 days.

METHODS

From February 2012 to November 2012, 47 patients were included in the study series. Before external radiotherapy the hydrogel was injected between prostate and rectum in the so-called Denovier space. This interdisciplinary procedure was carried out with the patient under general anesthesia using transrectal ultrasound guidance and video documentation. The patients were hospitalized for 1 day. The exact position of the gel was assessed by means of magnetic resonance imaging (MRI). Radiotherapy was initiated 7-14 days after gel application in a dose escalation manner by means of intensity modulated radiation therapy (IMRT) up to a dose of 80,0 Gy. Average follow-up was 241 (100-386, SD 91) days.

RESULTS

No early side effects specific for the application were observed. The achieved distance between rectum and the mid-plane of the prostate gland was on average 13.8 (6-24, SD=3.8) mm. Calculated V70 (rectal volume irradiated with 70.0 Gy or more) could be reduced to an average of 1.5 (0-8, SD=1.7) %. One patient showed an asymptomatic lesion of the rectal mucosa after irradiation with 38,0 Gy. This lesion was closely controlled and gel penetration was found. As a result radiotherapy was discontinued. Without further treatment the necrosis had completely healed 3 months later.

CONCLUSIONS

Hydrogel application between prostate and rectum allows dose escalation up to 80,0 Gy and seems to reduce morbidity in patients with localized prostate cancer receiving radiotherapy. However, before final judgement of the new technique further studies must follow.

Risk factors for postoperative CSF leakage after elective craniotomy and the efficacy of fleece-bound tissue sealing against dural suturing alone: a randomized controlled trial

OBJECT

Cerebrospinal fluid leakage is an immanent risk of cranial surgery with dural opening. Recognizing the risk factors for this complication and improving the technique of dural closure may reduce the associated morbidity and its surgical burden. The aim of this paper was to investigate whether the addition of TachoSil on top of the dural suture reduces postoperative CSF leakage compared with dural suturing alone and to assess the frequency and risk factors for dural leakage and potentially related complications after elective craniotomy.

METHODS

The authors conducted a prospective, randomized, double-blinded single-center trial in patients undergoing elective craniotomy with dural opening. They compared their standard dural closure by running suture alone (with the use of a dural patch if needed) to the same closure with the addition of TachoSil on top of the suture. The primary end point was the incidence of CSF leakage, defined as CSF collection or any open CSF fistula within 30 days. Secondary end points were the incidence of infection, surgical revision, and length of stay in the intensive care unit (ICU) or intermediate care (IMC) unit. The site of craniotomy, a history of diabetes mellitus, a diagnosis of meningioma, the intraoperative need of a suturable dural substitute, and blood parameters were assessed as potential risk factors for CSF leakage.

RESULTS

The authors enrolled 241 patients, of whom 229 were included in the analysis. Cerebrospinal fluid leakage, mostly self-limiting subgaleal collections, occurred in 13.5% of patients. Invasive treatment was performed in 8 patients (3.5%) (subgaleal puncture in 6, lumbar drainage in 1, and surgical revision in 1 patient). Diabetes mellitus, a higher preoperative level of C-reactive protein (CRP), and the intraoperative need for a dural patch were positively associated with the occurrence of the primary end point (p = 0.014, 0.01, and 0.049, respectively). Cerebrospinal fluid leakage (9.7% vs 17.2%, OR 0.53 [95% CI 0.23-1.15], p = 0.108) and infection (OR 0.18 [95% CI 0.01-1.18], p = 0.077) occurred less frequently in the study group than in the control group. TachoSil significantly reduced the probability of staying in the IMC unit for 1 day or longer (OR 0.53 [95% CI 0.27-0.99], p = 0.048). Postoperative epidural hematoma and empyema occurred in the control group but not in the study group.

CONCLUSIONS

Dural leakage after elective craniotomy/durotomy occurs more frequently in association with diabetes mellitus, elevated preoperative CRP levels, and the intraoperative need of a dural patch. This randomized controlled trial showed no statistically significant reduction of postoperative CSF leakage and surgical site infections upon addition of TachoSil on the dural suture, but there was a significant reduction in the length of stay in the IMC unit. Dural augmentation with TachoSil was safe and not related to adverse events. Clinical trial registration no. NCT00999999 ( http://www.ClinicalTrials.gov ).

[Prostate-rectum spacers: optimization of prostate cancer irradiation]

In the curative radiotherapy of localized prostate cancer, improvements in biochemical control observed with dose escalation have been counterbalanced by an increase in radiation-induced toxicity. The injection of biodegradable spacers between prostate and rectum represents a new frontier in the optimization of radiotherapy treatments for patients with localized disease. Transperineal injection of different types of spacers under transrectal ultrasound guidance allows creating a 7-to-20 mm additional space between the prostate and the anterior rectal wall lasting 3 to 12 months. Dosimetrically, a relative reduction in the rectal volume receiving at least 70 Gy (V70) in the order of 43% to 84% is observed with all types of spacers, regardless of the radiotherapy technique used. Preliminary clinical results show for all spacers a good tolerance and a possible reduction in the acute side effects rate. The aim of the present systematic review of the literature is to report on indications as well as dosimetric and clinical advantages of the different types of prostate-rectum spacers commercially available (hydrogel, hyaluronic acid, collagen, biodegradable balloon).

Evaluation of complication rates of pediatric spinal procedures in which a polyethylene glycol sealant was used

OBJECT

Cerebrospinal fluid leakage following durotomy in spinal surgery can lead to significant patient morbidity and mortality, including meningitis and even death. Usage of a polyethylene glycol (PEG) sealant in combination with standard closure techniques has been shown to be effective in preventing CSF leaks in animal models and adult patients, but the results of its use have not been reported in the pediatric population.

METHODS

A retrospective analysis was performed of pediatric neurosurgery patients (0-18 years of age) treated at The Johns Hopkins Hospital from 2003 to 2010. There were 93 spinal surgery patients identified in whom PEG was applied. The incidence of CSF leakage, meningitis, and neurological injury was recorded. There were 54 males and 39 females in this study with an average age of 8.7 years. Of the identified patients, 16.1%, 28%, and 55.9% underwent surgery in the cervical region, thoracic region, and lumbar region, respectively.

RESULTS

At 90-day follow-up, 5 patients (5.4%) had a CSF leak, 4 patients (4.3%) required a reoperation, and 1 patient (1.1%) had meningitis within this time period. No deaths or associated neurological deficits were observed.

CONCLUSIONS

The use of a PEG sealant to augment dural closure in pediatric spine surgery appears to be a safe adjunct to standard dural closure in pediatric spine patients.

Repair of middle fossa cerebrospinal fluid leaks using a novel combination of materials: technical note

OBJECT

Methods for repairing middle fossa CSF (MFCSF) leaks have varied and yielded mixed results. The objective of this study was to evaluate the safety and durability of the authors' repair technique using a novel combination of 3 synthetic materials.

METHODS

The authors performed a retrospective case review of patients treated for CSF leaks between January 2009 and September 2011. Eight patients were found to have undergone middle fossa craniotomies for CSF leaks. Inclusion criteria for the study included age greater than 18 years, neuroimaging-documented temporal bone defect, and symptoms consistent with CSF leaks or gross CSF otorrhea. Seven patients, 3 men and 4 women, met the inclusion criteria, and their charts were reviewed. Hydroxyapatite cement, collagen-based dural substitute matrix, and polyethylene glycol hydrogel sealant were used in all patients for the repair.

RESULTS

In all patients the MFCSF leaks were successfully repaired. Initial presenting symptoms included CSF otorrhea in 4 patients (57.1%), hearing loss in 3 (42.9%), and CSF rhinorrhea in 1 (14.3%). The mean follow-up duration was 12 months (range 5-33 months). In 1 patient an epidural hematoma developed at the operative site on postoperative Day 2, and in another patient a superficial wound dehiscence occurred on postoperative Day 48. During the follow-up period, the authors found no evidence of wound infections, neurovascular damage, or CSF leakage requiring reoperation.

CONCLUSIONS

The middle fossa approach involving a combination of hydroxyapatite cement, collagen-based dural substitute matrix, and polyethylene glycol hydrogel sealant is a safe, effective method for repairing MFCSF leaks. The combination of synthetic materials provides an alternative to existing materials for skull base surgeons.

Management of haemostasis in surgery: sealant and glue applications

Blood loss has always been a sensitive issue in surgery. Traditional techniques, such as suturing and electrocautery, have drastically reduced operatory bleeding. Unfortunately, wound edges and point application devices are frequently characterized by bleeding and infections. Over the past 20 years, haemostatic agents and tissue sealants have been developed and now are currently used, along with classic suture in various surgical specialties. Their fluid nature allows management of blood loss along any point of the wound and tissue repair. This review presents an overview of the most diffused haemostatic sealants, focusing on their main use in surgery and their adverse effects.

Fibrin sealant augmentation with autologous pericranium for duraplasty after suboccipital decompression in Chiari 1 patients: A case series

Background:

The Chiari 1 malformation (CM1) involves decent of the tonsils of the cerebellum through the foramen magnum. Symptomatic disease requires a posterior fossa decompression with or without an expansile duraplasty. To date, the optimal surgical treatment for CM1 has not been delineated. The extent of bony removal, size of the dural opening, necessity for expansion of the dural space, choice of materials for the duraplasty, and possible need for augmentation with dural sealant are all factors that continue to be debated amongst neurological surgeons worldwide. We herein evaluate the use of fibrin sealant augmentation in combination with locally harvested autologous pericranium for duraplasty in adult CM1 decompression.

Methods:

Retrospective data collected from January 2006 to December 2011. Data were reviewed for surgical site infection or meningitis, cerebrospinal fluid leak, symptomatic pseudomeningocele, radiographic improvement of hindbrain compression, and postoperative recurrence of symptoms at a minimum of 1 year of follow-up. Outcomes were studied clinically, radiographically, as well as by using a patient-specific questionnaire.

Results:

Twenty-two consecutive patients were included. One patient required a revision for a delayed graft dehiscence in the setting of a rare form of aseptic meningitis with cerebrospinal fluid (CSF) pleocytosis due to a nonsteroidal anti-inflammatory drug (NSAID) allergy. All remaining patients had successful decompressions with full resolution of their symptoms except for one patient who had persistent headaches.

Conclusion:

Autologous pericranium with dural sealant augmentation is an effective technique for expansile duraplasty in CM1 decompressions.

Application technique: placement of a prostate-rectum spacer in men undergoing prostate radiation therapy

What's known on the subject? and What does the study add? Different spacing agents have been tested to reduce incidential radiation exposure of the rectum during radiotherapy to the prostate. These agents all had certain drawbacks; either the created space was too small or the agents used did not stay in place during radiotherapy treatment. The study describes the transperineal injection technique of a spacing agent in detail. Furthermore it shows the safety and efficacy of the spacing hydrogel used and shows that it overcomes some of the drawbacks of the previously examined spacing agents.

OBJECTIVE

• To describe the technique used to apply a hydrogel spacer between the prostate and rectum so as to decrease the radiation dose to the rectum in patients with prostate cancer who are undergoing radiotherapy.

METHODS

• A prospective study evaluating the safety and efficacy of prostate-rectum spacer injection was conducted in 29 male patients with prostate cancer scheduled for radiotherapy. • Spacing hydrogel was injected into the perirectal space using a transperineal approach under real-time transrectal ultrasonography guidance. • With the needle tip positioned beyond the rectourethralis muscle, saline injection opened the space between Denonvilliers' fascia and the anterior rectal wall, allowing needle advancement to the mid-prostate without rectal wall injury. Injection of hydrogel precursors further opened this space, which was then maintained as a result of hydrogel polymerization. • Procedure duration and adverse events were monitored. Computed tomography and/or magnetic resonance imaging simulation scans were performed before and after injection. The hydrogel-created space was measured and the reduction in percent volume of the rectum receiving at least 70 Gy (rectal V70) was determined.

RESULTS

• Hydrogel injection resulted in mean (sd) additional prostate-rectum space relative to baseline of 9.87 (5.92) mm. • The mean (sd) procedure time, as measured by needle insertion and removal, was 6.3 (3.2) min. • The relative reduction in rectal V70 was 60.6%. • There were no unanticipated adverse events associated with the hydrogel procedure or the hydrogel.

CONCLUSIONS

• Hydrogel spacer injection using hydrodissection is a fast and effective procedure to separate the rectal wall from the prostate in order to avoid rectal toxicity. • Hydrogel spacer injection resulted in the addition of ∼1 cm of space • Computed incidental radiation exposure, the rectal V70, was substantially reduced.

The appearance of dural sealants under MR imaging

Dural sealants are an adjunct to obtain watertight closure after intradural procedures. This study aims to characterize the appearance on MR imaging of 3 commonly employed dural sealants: fibrin glue, PEGH, and BSAG. To this end, patients who underwent spinal intradural procedures that included the use of dural sealant during closure were identified retrospectively. Post-operative data on 15 patients, including complications such as pseudomeningocele formation and infection, were gathered. The appearance of dural sealants on follow-up MR imaging scans within 3 days of surgery was analyzed. Fifteen patients were identified (5 with fibrin glue, 5 with PEGH, and 5 with BSAG applied during closure) with appropriately timed post-operative MR imaging scans. All 3 substances were identifiable based on anatomic location and imaging characteristics on post-operative MR imaging in standard T1, T1 PGFS, and T2 FSE. Definite differentiation between CSF and fibrin glue or PEGH was not possible with the T1 or T1 PGFS, or with the T2 FSE. Differences in intensity between CSF and BSAG were also not significant on either T1 sequence, but they were statistically significant on the T2 FSE. All patients had an uneventful post-operative course, and no patients developed post-operative pseudomeningocele at 30 days. This study concludes that water-based dural sealants such as fibrin glue and PEGH are difficult to differentiate from CSF on standard T1, T1 PGFS and T2 FSE, while BSAG is easily recognized on the T2 FSE. Recognition of water-based sealants therefore requires communication between the neurosurgeon and the neuroradiologist to avoid post-operative misidentification.

A multicenter, single-blind, prospective randomized trial to evaluate the safety of a polyethylene glycol hydrogel (Duraseal Dural Sealant System) as a dural sealant in cranial surgery

OBJECTIVE

Incisional cerebrospinal fluid (CSF) leakage after cranial surgery is a significant cause of morbidity due to poor wound healing and infection, meningitis, and pseudomeningocele formation. Many common dural closure techniques, such as sutures, autologous grafts, gelatin or collagen sponges, and fibrin glues, are used to achieve watertight closure, although none are US Food and Drug Administration approved for this use. DuraSeal Dural Sealant System is a polyethylene glycol (PEG) hydrogel approved by the U.S. Food and Drug Administration for obtaining watertight dural closure when applied after standard dural suturing. This multicenter, prospective randomized study further evaluated the safety of a PEG hydrogel compared with common dural sealing techniques.

METHODS

A total of 237 patients undergoing elective cranial surgery at 17 institutions were randomized to dural closure augmented with the PEG hydrogel or a control "standard of care" dural sealing technique after Valsalva maneuver demonstrated an intraoperative nonwatertight dural closure. Data were collected on complications resulting in unplanned postoperative interventions or reoperations, surgical site infections, CSF leaks, and other neurological complications within 30 days. Surgeons also provided data on the ease of use of the dural sealing techniques, as well as preparation and application times.

RESULTS

The incidences of neurosurgical complications, surgical site infections, and CSF leaks were similar between treatment and control groups, with no statistically significant difference between the measures. In the PEG hydrogel group (n = 120), the incidence of neurosurgical complications was 5.8% (n = 7), the incidence of surgical site infections was 1.7% (n = 2), and the incidence of CSF leak was 0.8% (n = 1). In the control group (n = 117), the incidence of neurosurgical complications was 7.7% (n = 9), the incidence of surgical site infection was 2.6% (n = 3), and the incidence of CSF leak was 1.7% (n = 2). Sealant preparation time was less than 5 minutes in 96.6% of the PEG hydrogel group compared with 66.4% of controls (P < 0.001). The dural augmentation was applied in less than 1 minute in 85.7% of the PEG hydrogel group compared with 66.4% of the control group (P < 0.001).

CONCLUSIONS

The PEG hydrogel dural sealant used in this study has a similar safety profile to commonly used dural sealing techniques when used as dural closure augmentation in cranial surgery. The PEG hydrogel dural sealant demonstrated faster preparation and application times than other commonly used dural sealing techniques.

Polyethylene glycol (PEG) hydrogel dural sealant and collagen dural graft matrix in transsphenoidal pituitary surgery for prevention of postoperative cerebrospinal fluid leaks

Cerebrospinal fluid (CSF) rhinorrhea is the most common complication after transsphenoidal pituitary surgery. The authors compare their previous experience using an autologous fat graft and lumbar drain placement in 107 patients with their current technique of using a dural sealant and collagen matrix in 97 patients to prevent postoperative CSF leak after pituitary tumor resection. The failure rate for CSF leak repairs between the two groups was similar. The use of a dural sealant and collagen matrix, however, has the advantages of decreased length of hospital stay, decreased length of Intensive Care Unit stay, avoidance of the morbidity of an extra abdominal incision, and avoidance of the risks of lumbar CSF drainage.

Complications following decompression of Chiari malformation Type I in children: dural graft or sealant?

OBJECT

Posterior fossa decompression with duraplasty for Chiari malformation Type I (CM-I) is a common pediatric neurosurgery procedure. Published series report a complication rate ranging from 3% to 40% for this procedure. Historically, many dural substitutes have been used, including bovine grafts, human cadaveric pericardium, synthetic dura, and autologous pericranium. The authors hypothesized that a recently observed increase in complications was dependent on the graft used.

METHODS

Between January 2004 and January 2008, 114 consecutive patients ≤ 18 years old underwent primary CM-I decompression using duraplasty. Records were retrospectively reviewed for short- and intermediate-term complications and operative technique, focusing on the choice of duraplasty graft with or without application of a tissue sealant.

RESULTS

The average age of the patients was 8.6 years. The dural graft used was variable: 15 were treated with cadaveric pericardium, 12 with Durepair, and 87 with EnDura. Tisseel was used in 75 patients, DuraSeal in 12, and no tissue sealant was used in 27 patients. The overall complication rate was 21.1%. The most common complications included aseptic meningitis, symptomatic pseudomeningocele, or a CSF leak requiring reoperation. The overall complication rates were as follows: cadaveric pericardium 26.7%, Durepair 41.7%, and EnDura 17.2%; reoperation rates were 13%, 25%, and 8.1%, respectively. Prior to adopting a different graft product, the overall complication rate was 18.1%; following the change the rate increased to 35%. Complication rates for tissue sealants were 14.8% for no sealant, 18.7% for Tisseel, and 50% for DuraSeal. Nine patients were treated with the combination of Durepair and DuraSeal and this subgroup had a 56% complication rate.

CONCLUSIONS

Complication rates after CM-I decompression may be dependent on the dural graft with or without the addition of tissue sealant. The complication rate at the authors' institution approximately doubled following the adoption of a different graft product. Tissue sealants used in combination with a dural substitute to augment a duraplasty may increase the risk of aseptic meningitis and/or CSF leak. The mechanism of the apparent increased inflammation with this combination remains under investigation.