Risk Factors and Management of Incisional Cerebrospinal Fluid Leakage After Craniotomy: A Retrospective International Multicenter Study.

BACKGROUND: Incisional cerebrospinal fluid (iCSF) leakage is a serious complication after intradural cranial surgery. OBJECTIVE: To determine the incidence and risk factors of iCSF leakage after craniotomy. Secondarily, the complications after iCSF leakage and the success rate of iCSF leakage treatment was studied. METHODS: All patients who underwent an intradural cranial surgery from 2017 to 2018 at 5 neurosurgical centers were retrospectively included. Data were retrieved from medical records with 2 months of follow-up. First, univariate regression analyses were performed. Subsequently, identified risk factors were evaluated in a multivariate regression analysis. RESULTS: In total 2310 consecutive patients were included. Total iCSF leakage rate was 7.1% (n = 165). Younger age, male, higher body mass index, smoking, infratentorial surgery, and use of a dural substitute were associated with increased iCSF leakage risk, and use of a sealant reduced that risk. The odds for developing a wound infection and/or meningitis were 15 times higher in patients with iCSF leakage compared with patients without leakage. Initial conservative iCSF leakage treatment failed in 48% of patients. In 80% of cases, external cerebrospinal fluid drainage ceased the iCSF leakage. A total of 32% of patients with iCSF leakage required wound revision surgery. CONCLUSION: iCSF leakage risk increases by younger age, higher body mass index, smoking, infratentorial craniotomy, and dural substitute use, whereas sealant use reduced the risk for iCSF leakage. The leak increases the risk of postoperative infections. When iCSF leakage occurs, immediate external cerebrospinal fluid drainage or wound revision should be considered.

Histological and magnetic resonance imaging assessment of Liqoseal in a spinal in vivo pig model.

BACKGROUND: Liqoseal (Polyganics, B.V.) is a dural sealant patch for preventing postoperative cerebrospinal fluid (CSF) leakage. It has been extensively tested preclinically and CE (Conformité Européenne) approved for human use after a first cranial in-human study. However, the safety of Liqoseal for spinal application is still unknown. The aim of this study was to assess the safety of spinal Liqoseal application compared with cranial application using histology and magnetic resonance imaging characteristics. METHODS: Eight female Dutch Landrace pigs underwent laminectomy, durotomy with standard suturing and Liqoseal application. Three control animals underwent the same procedure without sealant application. The histological characteristics and imaging characteristics of animals with similar survival times were compared to data from a previous cranial porcine model. RESULTS: Similar foreign body reactions were observed in spinal and cranial dura. The foreign body reaction consisted of neutrophils and reactive fibroblasts in the first 3 days, changing to a chronic granulomatous inflammatory reaction with an increasing number of macrophages and lymphocytes and the formation of a fibroblast layer on the dura by day 7. Mean Liqoseal plus dura thickness reached a maximum of 1.2 mm (range 0.7-2.0 mm) at day 7. CONCLUSION: The spinal dural histological reaction to Liqoseal during the first 7 days was similar to the cranial dural reaction. Liqoseal did not swell significantly in both application areas over time. Given the current lack of a safe and effective dural sealant for spinal application, we propose that an in-human safety study of Liqoseal is the logical next step.

Cerebrospinal fluid leakage costs after craniotomy and health economic assessment of incidence reduction from a hospital perspective in the Netherlands.

OBJECTIVES: We aim to quantify the cost difference between patients with incisional cerebrospinal fluid (iCSF) leakage and those without after intradural cranial surgery. Second, the potential cost savings per patient when a decrease in iCSF leakage rate would be achieved with and without added costs for preventative measures of various price and efficacy are modelled. DESIGN: Health economic assessment from a hospital perspective based on a retrospective cohort study. SETTING: Dutch tertiary referral centre. PARTICIPANTS: We included 616 consecutive patients who underwent intradural cranial surgery between 1 September 2017 and 1 September 2018. Patients undergoing burr hole surgery or transsphenoidal surgery, or who died within 1 month after surgery or were lost to follow-up were excluded. PRIMARY AND SECONDARY OUTCOME MEASURES: Outcomes of the cost analysis include a detailed breakdown of mean costs per patient for patients with postoperative iCSF leakage and patients without, and the mean cost difference. For the scenario analyses the outcomes are the potential cost savings per 1000 patients when a decrease in iCSF leakage would be achieved. RESULTS: Mean cost difference between patients with and without iCSF leakage was €9665 (95%CI, €5125 to €14 205). The main cost driver was hospital stay with a difference of 8.5 days. A 25% incidence reduction would result in a mean cost saving of -€94 039 (95% CI, -€218 258 to -€7077) per 1000 patients. A maximum cost reduction of -€653 025 (95% CI, -€1 204 243 to -€169 120) per 1000 patients could be achieved if iCSF leakage would be reduced with 75% in all patients, with 72 cases of iCSF leakage avoided. CONCLUSIONS: Postoperative iCSF leakage after intradural cranial surgery increases healthcare costs significantly and substantially. From a health economic perspective preventative measures to avoid iCSF leakage should be pursued.

Minimizing complications in a porcine survival craniotomy model.

A large craniotomy survival porcine model is useful for scientific research. The surgical approaches and complications of craniotomies in pigs have not been published before. This study describes how large craniotomies were performed in 46 pigs and how the risk of complications was minimized. The major complications were direct postoperative epidural hematomas (n = 3) and sagittal sinus rupture (n = 4). The measures taken to prevent postoperative epidural hematomas consisted of optimizing anesthesia, using bone wax to stop trabecular bleeding, increasing blood pressure before bone flap replacement, tranexamic acid administration, and postoperative recovery of the pigs in the prone position in a dedicated hammock. After these measures, no pig died from a postoperative epidural hematoma. Iatrogenic sagittal sinus rupture occurred in cases where the dura shifted into the craniotome during craniotomy. The dura was detached from the skull through drill holes with custom elevators before craniotomy to minimize the risk of a sagittal sinus rupture. In conclusion, pigs can undergo craniotomy and survive if the right measures are put in place.

Safety and biodegradability of a synthetic dural sealant patch (Liqoseal) in a porcine cranial model.

Background: Liqoseal consists of a watertight layer of poly(ester)ether urethane and an adhesive layer containing polyethylene glycol-N-hydroxysuccinimide (PEG-NHS). It is designed to prevent cerebrospinal fluid (CSF) leakage after intradural surgery. This study assessed the safety and biodegradability of Liqoseal in a porcine craniotomy model. Methods: In 32 pigs a craniotomy plus durotomy was performed. In 15 pigs Liqoseal was implanted, in 11 control pigs no sealant was implanted and in 6 control pigs a control dural sealant (Duraseal or Tachosil) was implanted. The safety of Liqoseal was evaluated by clinical, MRI and histological assessment. The degradation of Liqoseal was histologically estimated. Results: Liqoseal, 2 mm thick before application, did not swell and significantly was at maximum mean thickness of 2.14 (±0.37) mm at one month. The foreign body reaction induced by Liqoseal, Duraseal and Tachosil were comparable. Liqoseal showed no adherence to the arachnoid layer and was completely resorbed between 6 and 12 months postoperatively. In one animal with Liqoseal, an epidural fluid collection containing CSF could not be excluded. Conclusion: Liqoseal seems to be safe for intracranial use and is biodegradable. The safety and performance in humans needs to be further assessed in clinical trials.

Histologic Comparison of the Dura Mater among Species.

The biocompatibility, biodegradation, feasibility, and efficacy of medical devices like dural sealants and substitutes are often evaluated in various animal models. However, none of these studies explain the rationale for choosing a particular species, and a systematic interspecies comparison of the dura is not available. We hypothesized that histologic characteristics of the dura would differ among species. We systematically investigated basic characteristics of the dura, including thickness, composition, and fibroblast orientation of the dura mater, in 34 samples representing 10 animal species and compared these features with human dura by using hematoxylin and eosin staining and light microscopy. Dura showed many similarities between species in terms of composition. In all species, dura consisted of at least one fibrovascular layer, which contained collagen, fibroblasts, and blood vessels, and a dural border cell layer beneath the fibrovascular layer. Differences between species included the number of fibrovascular layers, fibroblast orientation, and dural thickness. Human dura was the thickest (564 µm) followed by equine (313 µm), bovine (311 µm), and porcine (304 µm) dura. Given the results of this study and factors such as gross anatomy, feasibility, housing, and ethical considerations, we recommend the use of a porcine model for dural research, especially for in vivo studies.

Dural sealants for the management of cerebrospinal fluid leakage after intradural surgery: current status and future perspectives.

Introduction: Cerebrospinal fluid leakage is a complication after intradural surgery and is associated with severe secondary complications like compromised wound healing and meningitis. Dural sealants are meant to augment the primary dural closure in order to achieve a watertight closure. Areas covered: This review summarizes the efficacy of currently available dural sealants. Potential future improvements and biomaterials are discussed. Expert opinion: The use of a dural sealant seems to be the logical method to prevent CSF leakage. However, based on the efficacy of currently available dural sealants according to systematic reviews and in vitro studies, a significant effective dural sealant seems is still lacking. A new dural sealant has to be thoroughly assessed before clinical application in in vitro, in vivo and clinical trials. A new research area within sealant development might be the introduction of dural sealants with both antimicrobial and analgesic properties.

Effectiveness of Sealants in Prevention of Cerebrospinal Fluid Leakage after Spine Surgery: A Systematic Review.

BACKGROUND: Sealants are often used in spine surgery to prevent postoperative cerebrospinal fluid (CSF) leakage. OBJECTIVE: To investigate the efficacy of sealants in preventing postoperative CSF leakage in spine surgery. METHODS: The PubMed, Embase, and Cochrane databases were searched for articles reporting the outcome of patients treated with a sealant for spinal dural repair. The number of patients, indication of surgery, surgical site, applied technique, type of sealant used, and outcome in terms of postoperative CSF leakage were noted for each study. The primary outcome was CSF leakage in general and secondary outcome infection. RESULTS: Forty-one articles were selected with a total of 2542 cases; there were 4 comparative studies with 540 sealed cases and 343 cases with primary suture closure only. The quantity of CSF leakage did not differ between the sealant group (50 of 540, 9.1%) and the group treated with sutures only (48 of 343, 13.8%) (risk ratio [RR], 0.58 [confidence interval [CI], 0.18-1.82]). The infection rate did also not differ between the sealant and primary suture groups (RR, 0.94 [CI, 0.55-1.61]). This result was found in both the intended and the unintended durotomy subgroups. Secondary analysis of all cases showed that endoscopic or minimally invasive surgery had lower CSF leakage rates compared with open surgery regardless of sealant use (RR, 0.18 [CI, 0.05-0.75]). CONCLUSIONS: Currently available sealants seem not to reduce the rate of CSF leakage in spine surgery. In endoscopic and minimally invasive surgery, the CSF leakage rate is less frequent compared with open, conventional surgery regardless of sealant use.

Effectiveness of Dural Sealants in Prevention of Cerebrospinal Fluid Leakage After Craniotomy: A Systematic Review.

OBJECTIVE: Cerebrospinal fluid (CSF) leakage is one of the most challenging complications in neurosurgery. We sought to evaluate the efficacy of dural sealants in preventing CSF leakage after cranial surgery. METHODS: A literature search was performed in the PubMed, Embase, and Cochrane databases. The inclusion criteria were defined to include articles describing regular cranial procedures combined with the use of any dural sealant reporting CSF leakage. The primary outcome was CSF leakage (pseudomeningocele formation or incisional CSF leakage), secondary outcomes were pseudomeningocele formation, incisional CSF leakage, and surgical-site infection. RESULTS: Twenty articles were included. Ten of these were comparative studies (sealant vs. no sealant) including 3 randomized controlled trials. In the 20 articles, a total of 3682 surgical procedures were reported. The number of CSF leakages in general did not differ between the sealant group (8.2%) and control group (8.4%), risk ratio (RR) 0.84 (0.50-1.42), I2 = 56%. Exclusion of non-randomized controlled trials did not alter the results. Meta-analyses for secondary outcomes showed no difference between number of incisional CSF leakage, RR 0.30 (0.05-1.59), I2 = 38%. Also, no difference was found in the pseudomeningocele formation, RR 1.50 (0.43-5.17), I2 = 0%. Surgical-site infection was seen less in the sealant group (1.0%) compared with the control group (5.6%), RR 0.25 (0.13-0.48), I2 = 0%. CONCLUSIONS: This systematic review showed that dural sealants did not reduce the number of CSF leaks in general, the number of incisional CSF leaks alone, or the number of pseudomeningocele formations alone. However, dural sealants reduced the risk of surgical-site infection.

Usefulness of Sealants for Dural Closure: Evaluation in an In Vitro Model.

BACKGROUND: Cerebrospinal fluid (CSF) leakage occurs in 4% to 32% of cranial surgeries and is associated with significant patient burden and expense. The use of sealant as an adjunct to primary dural closure is assumed to help prevent CSF leakage. OBJECTIVE: To examine the utility of different sealants for dural closure using an in Vitro model. METHODS: We evaluated 9 commonly used dural sealants, including Tachosil (Takeda Inc, Osaka, Japan), Adherus (Hyperbranch Inc, Durham, North Carolina), Duraform (Codman, Raynham, Massachusetts), Tissudura (Baxter, Deerfield, Illinois), Hemopatch (Baxter), TissuePatchDural (Tissuemed, Leeds, United Kingdom), Tisseel (Baxter), Duragen Secure (Integra, Plainsboro, New Jersey), and Duraseal, (Integra). Sealants were tested in 2 novel in Vitro setups using fresh porcine dura: the first tested the acute burst pressure of a sealed 3-mm gap, while the second examined resistance to a pressure wave mimicking intracranial pressure for 72 h. RESULTS: Adherus showed the highest mean burst pressure (87 ± 47 mmHg) followed by Tachosil (71 ± 16 mmHg) and Duraseal (51 ± 42 mmHg); these were the only 3 sealants showing burst pressures above normal physiological intracranial pressure. In the 72-h setup, only Adherus and Duraseal maintained appropriate sealing for the duration of the experiment. Tachosil released from the dura after 1.4 h (95% confidence interval, -1.8-4.7). CONCLUSION: Given the high cost of sealants and the results of this study, we advocate a critical attitude toward sealant application as an adjunct to classic dural closure.

A Comparison of Surgical Treatments for Superior Semicircular Canal Dehiscence: A Systematic Review.

OBJECTIVE: We investigate the postoperative subjective and objective outcomes of different surgical treatments for superior semicircular canal dehiscence (SSCD): vestibular signs, auditory signs, vestibular evoked myogenic potential test, pure tone audiogram, speech audiogram, or video-nystagmography. DATA SOURCES: An electronic search performed in the PubMed, Cochrane Library, and EMBASE databases on 15th of September 2015. A systematic search was conducted. Articles were included if written in English, Dutch, German, or French language. STUDY SELECTION: Original studies reporting on the pre and postoperative subjective and/or objective outcomes of surgical treatments for superior semicircular canal dehiscence were included. DATA EXTRACTION: The methodological quality of the studies was independently assessed by two reviewers using a constructed critical appraisal, to assess the directness of evidence and the risk of bias. The results of the pre and postoperative subjective and/or objective outcomes were extracted. DATA SYNTHESIS: Comparative study was conducted. CONCLUSION: Surgical treatment for SSCD is particularly effective for vestibular symptoms and there is no evidence for improvement of hearing loss after surgical treatment. Since plugging using transmastoid approach had a lower complication rate, lower revision rate, and a shorter hospital stay, this treatment is recommended in high disabled SSCD patients.

Corrective Osteotomy for Intra-Articular Distal Humerus Malunion.

BACKGROUND: An intra-articular distal humerus malunion can be disabling. To improve function, reduce pain and/or prevent further secondary osteoarthritis an intra-articular corrective osteotomy can be considered. Herein we present the indications, practical guidelines for pre- operative planning and surgical technique. Subsequently, we provide long-term results in a small series. METHODS: We included six consecutive patients operated for intra-articular distal humerus malunion. Mean follow-up was 88 months. At lastest follow up elbow function was assessed according to standardized questionnaires and classification systems. RESULTS: All six patients healed their osteotomies. Three patients had a postoperative complication which were treated succesfully. Range of motion improved significantly and all patients were satisfied with the outcome. The elbow performance scores were good to excellent in all. Correlation analyses showed that age and level of osteoarthritis are very strong predictors for the long-term elbow function and quality of life. CONCLUSION: An intra-articular corrective osteotomy for a malunited distal humerus fracture is a worthwhile procedure. Based on our results it should particularly be considered in young patients with minimal osteoarthritis and moderate to severe functional disability and/or pain.

Surgical procedures of the elbow: a nationwide cross-sectional observational study in the United States.

BACKGROUND: Elbow surgery is shared by several subspecialties. We were curious about the most common elbow surgeries and their corresponding diagnoses in the United States. METHODS: We used the National Hospital Discharge Survey (NHDS) and the National Survey of Ambulatory Surgery (NSAS) data gathered in 2006-databases that together provide an estimate of all inpatient and ambulatory surgical care in the US. RESULTS: An estimated 150,000 elbow surgeries were performed in the US in 2006, 75% in an outpatient setting. The most frequent diagnosis treated operative was enthesopathy (e.g. lateral epicondylitis) and it was treated with several different procedures. More than three quarters of all elbow surgeries treated enthesopathy, cubital tunnel syndrome, or fracture (radial head in particular). Arthroscopy and arthroplasty accounted for less than 10% of all elbow surgeries. CONCLUSIONS: Elbow surgery in the United States primarily addresses enthesopathies such as tennis elbow, cubital tunnel syndrome, and trauma. It is notable that some of the most common elbow surgeries (those that address enthesopathy and radial head fracture) are some of the most variably utilized and debated.

In-Hospital Outcomes after Hemiarthroplasty versus Total Hip Arthroplasty for Isolated Femoral Neck Fractures.

BACKGROUND: Previous studies suggest total hip arthroplasty may have some benefits compared to hemi-arthroplasty for displaced intracapsular femoral neck fractures in patients more than 60 years of age. The primary research question of our study was whether in-hospital adverse events, post-operative length of stay (LOS) and mortality in patients 60 year of age or older differed between total hip and hemi-arthroplasty for femoral neck fracture. METHODS: We obtained data on 82951 patients more than 60 years of age with an isolated femoral neck fracture treated with either hemi-arthroplasty or total hip arthroplasty in 2009 or 2010 from the National Hospital Discharge Survey (NHDS) database. The International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9, CM) was used to code diagnoses, comorbidities, complications, and procedures. RESULTS: Controlling for demographics and comorbidities, patients treated with hemi-arthroplasty had a 40% (95% CI 1.4-1.5) higher risk of adverse events compared to patients treated with a total hip arthroplasty. Length of stay and in-hospital mortality did not differ between these groups. CONCLUSIONS: The observed advantage for total hip arthroplasty might reflect greater infirmity in hemi-arthroplasty patients that was not accounted for by ICD-9 codes alone.

Trends in bone graft use in the United States.

Bone graft and bone graft substitutes are used to provide structural support and enhance bone healing. Autogenous, allogeneic, and artificial bone grafts each have advantages and drawbacks. The development of allografts, synthetic bone grafts, and new operative techniques may have influenced the use of bone grafts in recent years. The goal of this study was to analyze the use of bone grafts and bone graft substitutes in the United States during a 16-year period. Using data from the National Hospital Discharge Survey, the authors analyzed the use of autogenous and artificial bone grafts in almost 2 million patients in the United States between 1992 and 2007 using International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) codes in 4 periods (1992-1995, 1996-1999, 2000-2003, and 2004-2007). Among an estimated almost 2 million bone graft procedures (83% autogenous, 17% artificial), the use of both types of grafts decreased. The main diagnoses for which bone grafts were used did not change; however, cervical spine diseases and lower-limb fractures decreased more remarkably. Although sex (52% male in the early 1990s to 47% in 2000-2003) and discharge status (more discharges to a short-term or long-term-care facility) significantly changed, age increased from 47 to 53 years and inpatient days decreased significantly from 6 to 5 days during the study period. The use of bone grafts and bone graft substitutes is decreasing in the United States, with a slight shift from autogenous to substitute grafts.

[Use of quality assessments by internists: added pressure to carry out assessments or an aid to improve quality?]. / Gebruik van kwaliteitsevaluaties door internisten: belastende evaluatiedruk of hulp bij kwaliteitsverbetering?

OBJECTIVE: To obtain an insight into how internists and residents use quality assessments and their opinions on these assessments. DESIGN: Questionnaire survey. METHOD: All 139 internists and residents who attended a national training day on internal medicine in 2012 were invited to answer questions anonymously on the actual use of various quality assessments and to give their opinion on these assessments. The questionnaire consisted of closed and free text questions. The answers were analysed using descriptive statistics. The qualitative information was analysed together by the investigators. RESULTS: In total 123 doctors (88% of the 139 attendants at the training day) from 45 training hospitals (74% of all internal medicine residency training programs) participated in this study. All respondents had recently participated as an individual or as a member of a group in one or more quality assessments. Medical departments and group practices carried out quality assessments more often than required in many cases. Respondents recognised and acknowledged the advantages of quality assessments. The disadvantages of quality assessments related to the methods, the ways assessments were used and undesirable effects. Most of the medical departments and group practices developed policies on how to follow up on the assessment results. Individual performance data was also discussed in the majority of cases. CONCLUSION: Internists (whether or not undergoing training) make extensive and intensive use of quality assessments. The benefits and the weaknesses of quality assessments are both acknowledged. Proactive efforts are required so that improvements can be made in addition to the assessments.

Carpal tunnel syndrome: assessment of surgeon and patient preferences and priorities for decision-making.

PURPOSE: This study tested the null hypothesis that there are no differences between the preferences of hand surgeons and those patients with carpal tunnel syndrome (CTS) facing decisions about management of CTS (ie, the preferred content of a decision aid). METHODS: One hundred three hand surgeons of the Science of Variation Group and 79 patients with CTS completed a survey about their priorities and preferences in decision making regarding the management of CTS. The questionnaire was structured according the Ottawa Decision Support Framework for the development of a decision aid. RESULTS: Important areas on which patient and hand surgeon interests differed included a preference for nonpainful, nonoperative treatment and confirmation of the diagnosis with electrodiagnostic testing. For patients, the main disadvantage of nonoperative treatment was that it was likely to be only palliative and temporary. Patients preferred, on average, to take the lead in decision making, whereas physicians preferred shared decision making. Patients and physicians agreed on the value of support from family and other physicians in the decision-making process. CONCLUSIONS: There were some differences between patient and surgeon priorities and preferences regarding decision making for CTS, particularly the risks and benefits of diagnostic and therapeutic procedures. CLINICAL RELEVANCE: Information that helps inform patients of their options based on current best evidence might help patients understand their own preferences and values, reduce decisional conflict, limit surgeon-to-surgeon variations, and improve health.

Unusual radial nerve injury by a locking compression plate for humerus fracture.

The management of primary and secondary radial nerve palsy associated with humeral shaft fractures is still controversial. Radial nerve function is likely to return spontaneously after primary as well as secondary radial nerve palsy in the absence of any level of neurotmesis. Identification and protection of the radial nerve during surgery may prevent secondary nerve palsy, but is not always performed and depends on the location of the fracture, and the experience and preference of the surgeon. We report a case of a healthy 40-year-old woman, referred to our hospital with a complete radial nerve palsy and a failed plate fixation of a right humeral shaft fracture. During exploration of the radial nerve and surgical revision of the fracture, we found the nerve entrapped by the plate and partially transected by a screw. Full recovery of radial nerve function occurred after neurolysis and microscopic neurorrhaphy.

Diagnostic accuracy of 2- and 3-dimensional computed tomography and solid modeling of coronoid fractures.

PURPOSE: This study measured the diagnostic performance characteristics and reliability of 2-dimensional (2DCT) and 3-dimensional (3DCT) computed tomography images and modeling of coronoid fractures. METHOD: The treating surgeon and first assistant evaluated 28 fractures for fracture type, specific characteristics, and proposed treatment. The observers evaluated the fractures 4 times: first based upon 2DCT computed images and radiographs; second with the addition of 3DCT images; third with the addition of 3D models; and finally based upon intra-operative exposure, which was considered the reference standard. RESULTS: The diagnostic performance characteristics did not improve with more sophisticate imaging and models. The addition of 3DCT reconstructions improved the inter-observer reliability for fracture classification, characteristics, and proposed treatment. CONCLUSION: More sophisticated images and modeling improved reliability but not accuracy when characterizing coronoid fractures.