Topical hemostatic agents in neurosurgery, a comprehensive review: 15 years update.

Hemostasis in neurosurgery is of utmost importance. Bleeding management is one of the crucial steps of each neurosurgical procedure. Several strategies, namely thermal, mechanical, electric, and chemical, have been advocated to face blood loss within the surgical field. Over time, countless hemostatic agents and devices have been proposed. Furthermore, the ever-growing recent technological innovation has made available several novel and interesting tools. Pursuant to their impact on surgical practice, we perceived the imperative to update our previous disclosure paper. Therefore, we reviewed the literature and analyzed technical data sheets of each product in order to provide an updated and comprehensive overview in regard to chemical properties, mechanisms of action, use, complications, tricks, and pitfalls of topical hemostatic agents.

Clinical and radiological outcome after minimally invasive surgical approach for type II unstable odontoid fractures.

INTRODUCTION: Anterior odontoid screw fixation is a valid surgical option for unstable odontoid fractures, as type II Anderson D'Alonzo fractures. Grauer further divided type II fractures in subtypes according to the fracture line, providing recommendations for implementation of screw fixation techniques. OBJECTIVE: Primary endpoint of our study is to evaluate the postoperative results of minimally invasive odontoid screw insertion in terms of outcome, fusion rate and stability of cranio-cervical junction. Secondary endpoint was to investigate the influence of age or fractures' features on outcome and fusion rate. MATERIALS AND METHODS: We report the clinical and radiological features of 32 patients harbouring unstable type II fractures operated by a minimally invasive odontoid screw insertion technique. All patients underwent a high resolution multiplanar CT in order to assess fracture features according to Grauer's classification; the integrity of ligaments was investigated by MRI. In addition, a preoperative neurological performance (modified Rankin Scale, mRS) was evaluated for patients either directly or interviewing their families. Follow-up at one, three and six months and 1 year have been performed (averaging 13.5 months) by cervical CT (fusion rate and stability) and mRS update. In order to investigate the influence of age on postoperative neurological performance, two groups (≤50 yrs, 9 pts/>50 yrs, 23 pts) were separately considered and analysed. Overall, we observed no surgery related complications. We also analysed the fusion rate and its correlation with patient age and Grauer's subtype of fracture. RESULTS: At last available clinical follow-up, the preoperative performance was preserved (mRS 0/1: 24, 75%; mRS 2-4: 9, 15%) although with slight reduction of intact patients (mRS 0: 22 vs. 19; 71.8 vs. 59.3%). Younger patients (≤50 yrs) fared significantly better than older ones, achieving a good clinical outcome (mRS 0/1) in 100% vs. 69.5% (9/9 vs. 16/23 pts). Statistical analysis showed a fair correlation between age and outcome. Other factors such as sex and Grauer's type did not influence significantly the clinical outcome. Nine patients did not complete a full radiological follow-up and were therefore excluded from analysis of radiological outcome. Among the remaining 23 patients, only 25% of those who were followed three months or less showed fusion; conversely, all patients who have been examined from 6 to 48 months fused. Among the non-union patients, two underwent a second surgery by posterior approach. CONCLUSIONS: In our recent experience, the minimally invasive AOSF proved safe and effective in treating odontoid peg fractures. Selection based on Grauer's type is mandatory to achieve best results. While in the elderly, an anterior approach is well accepted as the first choice treatment, we recommend that this option should be offered as a suitable alternative to Halo or orthosis also in younger patients since it provides prompt, excellent clinical outcome and high fusion rate especially in this age group.

[Cervical disc herniation--diagnosis and treatment]. / Hernie discale cervicate--diagnostic et prise en charge.

A cervical disc herniation (CDH) is a frequently encountered pathology in primary care medicine. It may give rise to a compression of a nerve root (a radiculopathy, with or without sensory-motor deficit) or of the spinal cord (myelopathy). The majority of CDHs can be supported by means of a conservative treatment. When a radiculopathy is found and a clinico-radiological correlation is present, a moderate neurological deficit appears suddenly, or if it is progressive under conservative treatment or if pain is poorly controlled by well-conducted conservative treatment performed during 6 to 8 months, surgery is then recommended. A symptomatic cervical myelopathy is, by itself, an indication for a surgical treatment.

[Minimally invasive spine surgery: past and present]. / Chirurgie du rachis lombaire minimalement invasive: passé et present d'une technique pleine d'avenir.

In the early twentieth century, the understanding of spine biomechanics and the advent of surgical techniques of the lumbar spine, led to the currently emerging concept of minimal invasive spine surgery, By reducing surgical access, blood loss, infection rate and general morbidity, functional prognosis of patients is improved. This is a real challenge for the spine surgeon, who has to maintain a good operative result by significantly reducing surgical collateral damages due to the relatively traumatic conventional access.

Clinically relevant complications related to posterior atlanto-axial fixation in atlanto-axial instability and their management.

BACKGROUND: The Magerl transarticular technique and the Harms-Goel C1 lateral mass-C2 isthmic screw technique are the two most commonly used surgical procedures to achieve fusion at C1-C2 level for atlanto-axial instability. Despite recent technological advances with an increased safety, several complications may still occur, including vascular lesions, neurological injuries, pain at the harvested bone graft site, infections, and metallic device failure. METHODS: We retrospectively analyzed all patients (n=42 cases) undergoing a Harms-Goel C1-C2 fixation surgery with polyaxial C1 lateral mass screws and C2 isthmic screws at two different institutions between 2003 and 2012 and report clinical and radiological complications. One patient was lost to follow-up. The mean follow-up of the remaining 41 patients was 18.7 months (range 12-90). A clinically relevant complication was defined as a complication determining the onset of a new neurological deficit or requiring the need for a revision surgery. RESULTS: A total of 14 complications occurred in 10 patients (24.4% of 41 patients). Greater occipital nerve neuralgia was evident in 4 patients (9.8%). All but one completely resolved at the end of the follow-up. Persistent neck pain was reported by 3 patients (7.3%), hypoesthesia by 1 patient (2.4%), and anesthesia in the C2 area on both sides in 1 patient (2.4%). Furthermore, a superficial, a deep, and a combined superficial and deep wound infection occurred in 1 patient each (2.4%). One patient (2.4%) had pain at the iliac bone graft donor site for several weeks with spontaneous resolution. A posterior progressive intestinal herniation through the iliac scar was seen in 1 case (2.4%), which required surgical repair. No vascular damages occurred. Altogether, 5/41 patients (12.2%) had a clinically relevant complication including 4 patients necessitating a revision surgery at the C1-C2 level (9.8%). CONCLUSIONS: Atlanto-axial fixation surgery remains a challenging procedure because of the proximity of important neurovascular structures. Nevertheless, on the basis of our current experience, the C1 lateral mass-C2 isthmic screw technique appears to be safe with a low incidence of clinically relevant complications. Postoperative C2 neuralgia, as the most frequent problem, is due to surgical manipulation during preparation of the C1 screw entry point.

Acute traumatic central cord syndrome: a comprehensive review.

Acute traumatic central cord syndrome (ATCCS) is the most common type of incomplete spinal cord injury, characterized by predominant upper extremity weakness, and less severe sensory and bladder dysfunction. ATCCS is thought to result from post-traumatic centro-medullary hemorrhage and edema, or, as more recently proposed, from a Wallerian degeneration, as a consequence of spinal cord pinching in a narrowed canal. Magnetic Resonance Imaging is the method of choice for diagnosis, showing a typical intramedullary hypersignal on T2 sequences. Non-surgical treatment relies on external cervical immobilization, maintenance of a sufficient systolic blood pressure, and early rehabilitation, and should be reserved for patients suffering from mild ATCCS. Surgical management of ATCCS consists of posterior, anterior or combined approaches, in order to achieve spinal cord decompression, with or without stabilization. The benefits of early surgical decompression in the setting of ATCCS remain controversial due to the lack of clinical randomized trials; recent studies suggest that early surgery (less than 72hours after trauma) appears to be safe and effective, especially for patients with evidence of focal anatomical cord compression.

[Lumbar disc herniation--diagnosis and treatment]. / Hernie discale lombaire--diagnostic et prise en charge.

A lumbar disc herniation (LDH) is a condition frequently encountered in primary care medicine. It may give rise to a compression of one or more nerve roots, which can lead to a nerve root irritation, a so-called radiculopathy, with or without a sensorimotor deficit. The majority of LDHs can be supported by means of a conservative treatment consisting of physical therapy, ergotherapy, analgetics, anti-inflammatory therapy or corticosteroids, which may be eventually administered by infiltrations. If a clinico-radiological correlation is present and moderate neurological deficit appears suddenly, if it is progressive under conservative treatment or if pain is poorly controlled by well-conducted conservative treatment performed during four to six months, surgery is then recommended.

Renal carcinoma relapse presenting as a peripheral nerve sheath tumor: A case report and brief review of the literature.

We report a rare case of renal carcinoma metastasis involving a lumbar nerve root. Metastases to nerve roots are rare occurrences, and to our knowledge, only six cases have been reported so far in the literature. The patient in this report presented with weakness in the right lower limb and intractable pain irradiating along the L5 dermatome. MRI findings revealed a right-sided L5 nerve root mass, suggestive of a schwannoma, involving the spinal ganglion and its extraforaminal region. Complete macroscopic resection of this mass was performed, and histopathologic analysis confirmed the lesion to be a metastasis of a renal clear cell carcinoma. Local radiotherapy was given and tyrosine kinase inhibitors administered. At 5 months, the patient was pain-free and his right limb weakness had completely resolved. A tumoral recurrence could be observed on the control MRI 5 months after surgery. This report presents the first case of a patient with a renal clear cell carcinoma metastasis to a L5 nerve root, as well as a brief review of previous cases of metastases to peripheral nerve roots.

Fibrillary structure is key for hemostasis: a similar effect of collagen fleece and oxidized cellulose on experimental hemorrhagic brain injury.

BACKGROUND: The choice of the ideal hemostatic agent for intraoperative cerebral bleeding is under continuous debate. Our aim was to assess the influence of such materials on bleeding time in hemorrhagic cerebral contusions. We compared oxidized regenerated cellulose in fibrillar form (ORC) to microfibrillar collagen fleece (CF) in an experimental study. METHODS: N=50 Sprague Dawley rats underwent a bilateral craniectomy. 3 separate standardized superficial cortical impacts were inflicted using a high-speed drill. Immediately after lesion placement, each of the 3 lesions was covered with (a) nothing (control), (b) ORC, or (c) CF. We observed the 3 lesions with a surgical microscope. The bleeding times were recorded for each cerebral lesion and compared using ANOVA test. RESULTS: All traumatic lesions produced significant bleeding. The statistical analysis showed a clear reduction in bleeding time for groups treated with either ORC or CF compared to the control group. Lesions covered with ORC and CF showed no significant difference with regard to bleeding time. CONCLUSIONS: ORC and CF significantly reduce blood loss from hemorrhagic contusions. Our data suggest that they effectively reduce bleeding time. We advocate the use of hemostatic material for limiting bleeding from superficial cortical lesions.

Posterior atlanto-axial fixation with polyaxial C1 lateral mass screws and C2 pars screws.

PURPOSE: C1-C2 instability or painful osteoarthritis are recognised indications for posterior atlanto-axial fixation. In the traditional trans-articular C1-C2 screw fixation, up to 20% of patients cannot have safe placement of bilateral screws in the event of a medially located vertebral artery and a straight screw trajectory in the sagittal plane. The more recently developed C1-C2 fixation technique with individual C1 lateral mass screws and converging C2 pars screws can be employed in case of a medially located vertebral artery and has comparable biomechanical strength. This is a prospective observational study to investigate the advantages, the safety, and the drawbacks of posterior atlanto-axial fixation with polyaxial C1 lateral mass screws and C2 pars screws. METHODS: Twelve consecutive patients with C1-2 instability (n = 11) and painful osteoarthritis (n = 1) underwent a posterior atlanto-axial fixation with polyaxial C1 lateral mass screws and C2 pars screws. The average follow-up was 16 months and all patients reached the 12-month follow-up. FINDINGS: No hardware failure occurred in any of the patients. Correct screw placement and construct stability was found in all 12 patients (100%) at 6 and 12 months after surgery. Mean neck pain on a visual analogue scale (VAS) was 2.1 at 6 months and 2.0 at 12 months. Only transient complications were observed: one patient presented with progressive intestinal herniation through the iliac crest scar; one suffered from severe pain at the posterior iliac crest for 3 months and three patients complained of annoying pain/dysaesthesia in the C2 dermatome for 3-6 months after surgery. CONCLUSION: This study confirms that posterior atlanto-axial fixation with polyaxial C1 lateral mass screws and C2 pars screws is a safe and effective surgical option in the treatment of atlanto-axial instability or painful osteoarthritis.

[Non fusion techniques in spinal surgery]. / Techniques de "non-fusion" en chirurgie rachidienne.

In order to prevent adjacent segment degeneration following spinal fusion new techniques are being used. Lumbar disc arthroplasty yields mid term results equivalent to those of spinal fusion. Cervical disc arthroplasty is indicated in the treatment of cervicobrachialgia with encouraging initial results. The ability of arthroplasty to prevent adjacent segment degeneration has yet to be proven. Although dynamic stabilization had not been proven effective in treating chronic low back pain, it might be useful following decompression of lumbar spinal stenosis in degenerative spondylolisthesis. Interspinal devices are useful in mild lumbar spinal stenosis but their efficacy in treating low back pain is yet to be proven. Confronted with a growing number of new technologies clinicians should remain critical while awaiting long term results.

Elevated levels of tumor necrosis factor-alpha in periradicular fat tissue in patients with radiculopathy from herniated disc.

STUDY DESIGN: Case-control study. OBJECTIVE: To determine whether inflammatory cytokines [tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, IL-6 and IL-8] are elevated in tissues intimately surrounding involved nerve roots of patients suffering from radiculopathy form herniated disc (HD). SUMMARY OF BACKGROUND DATA: Proinflammatory cytokines are postulated to play an important role in radiculopathy from HD. Although TNF-alpha has been found in human HD, it is not known whether TNF-alpha concentrations are increased in symptomatic patients. Epidural fat (EF) is another tissue in close contact with nerve roots. Histologic modifications of EF have been reported in patients with sciatica but concentrations of inflammatory cytokines have never been studied. METHODS: Twenty-three lumbar HD along with adjacent EF (EFHD) were harvested from patients with radicular syndrome. As controls, 14 intervertebral discs (IVDs) and 10 samples of EF (EFC) were obtained from patients without radicular syndrome undergoing spine surgery. Tissue explants were incubated ex vivo for 48 hours and the concentrations of cytokines were measured by elisa in the supernatants. Results were standardized according to tissue weight. RESULTS: All 4 cytokines were found at higher concentrations in EFHD compared with HD (P < 0.001). TNF-alpha was the only cytokine found in significantly higher levels in EFHD compared with EFC [median, interquartile range 6.6, (1.6-16.3) pg/mL per milligram of tissue vs. 2.3 (1.3-5.0), P < 0.05] and to subcutaneous fat [0.35 (0-2.28), P < 0.001]. No significant increase of either cytokines was found in HD compared with IVD. CONCLUSION: Higher concentrations of TNF-alpha were found in EF from patients with radiculopathy from HD compared with patients suffering from other type of back pain. These results support the role of TNF-alpha in the pathogenesis of radiculopathy from HD.

C-reactive protein and coronary composition in patients with percutaneous revascularization.

BACKGROUND: C-Reactive Protein (CRP) is considered a predictive factor for cardiovascular events and its serum levels have been shown to correlate with thin cap coronary plaques in sudden coronary death. Whether serum CRP levels are associated with in vivo atherothrombotic features is unclear. We thus analysed samples from coronary atherectomy specimens obtained during percutaneous coronary intervention. MATERIALS AND METHODS: Patients with coronary artery disease undergoing directional atherectomy, distinguished by unstable versus stable coronary syndrome diagnosis, provided coronary specimens from culprit lesions. Assessment was conducted by means of conventional histology, morphometry and immunohistochemistry. Specific antibodies against erythrocyte-specific protein glycophorin A, endothelial and macrophage antigens were also used. RESULTS: There were 51 patients with unstable coronary disease and 47 patients with stable angina. Serum CRP levels >/= 1 mg L(-1) were detected in 24/98 patients, and were significantly associated with hypercellularity, macrophage infiltrates, neoangiogenesis and intraplaque haemorrhage (all P < 0.05). Furthermore, coronary plaques from patients with unstable angina contained larger atheromas, more hypercellular plaques, with abundant macrophages, neoangiogenesis and intraplaque haemorrhages and lesser fibrous tissue (all P < 0.05). CONCLUSIONS: We observed a positive correlation between increased serum CRP levels and typical pathological features of complex atherothrombotic coronary disease, confirming in vivo the mechanistic role of CRP in coronary atherothrombosis.

Management of benign craniovertebral junction tumors.

BACKGROUND: We report our surgical experience in the treatment of fifteen consecutive patients with benign craniovertebral junction tumors, observed from 1993 to 2000 at our department. METHOD: We treated 7 meningiomas, 3 epidermoids, 3 C1 neurinomas and 2 neurinomas of the lower cranial nerves. Clinical results were evaluated by Karnofsky Performance Scale and all patients underwent preoperative neuroradiological evaluation with CT, MRI and MRA; angiography was not routinely performed and was considered for each individual case. FINDINGS: 11 partial transcondilar and 4 retrocondilar approaches were performed. Total removal was achieved in 11 cases (73,3%) and subtotal removal in 4 patients (26,7%). None of the patients required occipitocervical fusion. Patients were followed for an average period of 24+/-31 months. Clinical and radiological follow-up showed no recurrence in cases with total removal. In all patients a statistically significant postoperative increase of KPS scores was recorded. The treatment of epidermoid tumors presented particular issues: debulking the lesion, we obtained a surgical window, avoiding a large removal of bone. In Nakasu grade 1 or 2 meningiomas, we carried out total removal by piecemeal resection and without complete condylectomy and bone fixation. INTERPRETATION: The choice of these approaches and the extent of bone resection should be defined according to the tumor's location and size. Moreover we emphasize that preoperative neuroradiological evaluations on presumptive tumor type could be helpful to the surgeon in order to tailor the technique to different lesions, providing the required exposure, without unnecessary surgical steps.

Duplicated abducent nerve and its course: microanatomical study and surgery-related considerations.

OBJECT: The anatomy of the abducent nerve is well known; its duplication (ranging from 5 to 28.6%), however, has rarely been reported in the literature. The authors performed a microanatomical study in 100 cadaveric specimens (50 heads) to evaluate the prevalence of this phenomenon and to provide a clear anatomical description of the course and relationships of the nerve. The surgery-related implications of this rare anatomical variant will be highlighted. METHODS: The 50 human cadaveric heads (100 specimens) were embalmed in a 10% formalin solution for 3 weeks. Fifteen of them were injected with colored neoprene latex. A duplicated abducent nerve was found in eight specimens (8%). In two (25%) of these eight specimens the nerve originated at the pontomedullary sulcus as two independent trunks: in one case the superior trunk was thicker than the inferior and in the other it was thinner. In the other six cases (75%) the nerve originated as a single trunk, splitting in two trunks into the cisternal segment: in two of them the trunks ran below the Gruber ligament, whereas in four specimens one trunk ran below and one above it. In all the specimens, the duplicated nerves fused again into the cavernous sinus, just after the posterior genu of the internal carotid artery. CONCLUSIONS: Although the presence of a duplicated abducent nerve is a rare finding, preoperative magnetic resonance imaging should be performed to rule out this possibility, thus tailoring the operation to avoid postoperative deficits.

Lumbosacral dural ectasia in type 1 neurofibromatosis. Report of two cases.

Dural ectasia denotes circumferential expansion or dilatation of the dural sac, and has been frequently reported in association with type 1 neurofibromatosis (NF1). The pathogenesis has not been defined, but its correlation with NF1 infers a congenital malformative hypothesis. The neural elements in the dilated sleeve typically are not enlarged or abnormal, nevertheless the enlarged area contain an increased amount of cerebrospinal fluid. The dura in the area of ectasia is extremely thin and fragile, and erodes the surrounding bony structures destabilising the spine and permitting spectacular spinal deformities. We present two cases with lumbosacral dural ectasia, enlargement of the intervertebral foramina and posterior scalloping of vertebral bodies. Neurological examination showed sciatic nerve irritation. As the etiology of this malformation remains uncertain and dysplastic changes of the spine may be intrinsic or secondary controversies remain about optimum treatment. We conclude that patients affected by NF-1 require an accurate neuroradiological study of the whole spine in order to detect possible dural and spinal anomalies. Surgical treatment is indicated only in patients with progressive neurological deterioration. The thin dural sac predisposes to a high morbidity if surgery is undertaken.

Traumatic subependymal hematoma during endoscopic third ventriculostomy in a patient with a third ventricle tumor: case report.

Endoscopic third ventriculostomy has become a routine intervention for the treatment of non-communicating hydrocephalus. This technique is largely considered safe and a very low incidence of complications is reported. However, hemorrhage in the course of neuroendoscopy is still a problem difficult to manage. The authors present a case in which endoscopic third ventriculostomy and tumor biopsy were performed in a young patient with a huge tumor growing in the posterior part of the third ventricle. The surgical approach to realize the stoma was difficult because the tumor size reduced the third ventricle diameter. Surgical manipulation produced a traumatic subependymal hematoma. This hematoma drained spontaneously after few minutes into the ventricle and the blood was washed away. The postoperative neurological course was uneventful and the ventriculostomy showed to work well by reducing the size of the lateral ventricles and the intracranial pressure in three days. This complication during endoscopic third ventriculostomy has never been reported before. We emphasize the difficulty of endoscopic procedures in patients with huge tumors in the third ventricle. Where reduction in size of the third ventricle and of the foramen of Monro ist present we suggest a careful approach to the third ventricle.

Tolosa-Hunt syndrome preceded by facial palsy.

The Tolosa-Hunt syndrome consists of a painful ophthalmoplegia related to a granulomatous inflammatory process in the cavernous sinus, which may be documented by cerebral magnetic resonance imaging with gadolinium enhancement. Two cases of Tolosa-Hunt syndrome preceded by facial palsy observed in 1998 at the Department of Neurosurgery of the Second University of Naples are presented here. Both patients developed Tolosa-Hunt syndrome following an ipsilateral facial palsy that resolved in about 15 days with medical treatment. Cerebral magnetic resonance imaging with gadolinium enhancement showed, in both cases, inflammatory tissue in the cavernous sinus. The patients underwent corticosteroid therapy (prednisolone, 80 mg per day, intravenously) with pain regression. In the first case, the patient experienced recurrence of the syndrome that was definitively resolved with further corticosteroid treatment. The rare reports of facial palsy in patients with Tolosa-Hunt syndrome suggest the inclusion of this disease in the so-called multiple cranial nerve palsy syndrome. It is probable that Tolosa-Hunt syndrome has an inflammatory pathogenesis.