Development of a Novel Device for Decompressive Craniectomy: An Experimental and Cadaveric Study and Preliminary Clinical Application

BACKGROUND

Decompressive craniectomy is an intervention of established efficacy in patients with intractable cerebral edema.

OBJECTIVE

To evaluate a new device used in alternative to decompressive craniectomy. This device is designed to perform an augmentative craniotomy by keeping the bone flap elevated using specific cranial suspension titanium plates and giving the brain enough room to swell.

METHODS

We tested the mechanical characteristics of the cranial brackets on dried skulls, on 3D-printed skull models, and on a preserved cadaver head. The resistance of the device was examined through dynamometric testing, and the feasibility of the surgical technique, including the suspension of the bone flap and the skin closure, was investigated on the cadaveric model. A preliminary clinical series of 2 patients is also reported.

RESULTS

The laboratory tests have shown that this system allows an adequate expansion of the intracranial volume and it could withstand a force up to 637 ± 13 N in the synthetic model and up to 658 ± 9 N in the human skull without dislocation or failure of the brackets nor fractures of the bone ridges. Preliminary application in the clinical setting has shown that augmentative craniotomy is effective in the control of intracranial hypertension and could reduce the costs and complications associated with the classical decompressive craniectomy technique.

CONCLUSION

Preliminary laboratory and clinical results show augmentative craniotomy to be a promising, alternative technique to decompressive craniectomy. Further clinical studies will be needed to validate its efficacy.

Cortical atrophy in chronic subdural hematoma from ultra-structures to physical properties

Several theories have tried to elucidate the mechanisms behind the pathophysiology of chronic subdural hematoma (CSDH). However, this process is complex and remains mostly unknown. In this study we performed a retrospective randomised analysis comparing the cortical atrophy of 190 patients with unilateral CSDH, with 190 healthy controls. To evaluate the extent of cortical atrophy, CT scan images were utilised to develop an index that is the ratio of the maximum diameter sum of 3 cisterns divided by the maximum diameter of the skull at the temporal lobe level. Also, we reported, for the first time, the ultrastructural analyses of the CSDH using a combination of immunohistochemistry methods and transmission electron microscopy techniques. Internal validation was performed to confirm the assessment of the different degrees of cortical atrophy. Relative Cortical Atrophy Index (RCA index) refers to the sum of the maximum diameter of three cisterns (insular cistern, longitudinal cerebral fissure and cerebral sulci greatest) with the temporal bones' greatest internal distance. This index, strongly related to age in healthy controls, is positively correlated to the preoperative and post-operative maximum diameter of hematoma and the midline shift in CSDH patients. On the contrary, it negatively correlates to the Karnofsky Performance Status (KPS). The Area Under the Receiver Operating Characteristics (AUROC) showed that RCA index effectively differentiated cases from controls. Immunohistochemistry analysis showed that the newly formed CD-31 positive microvessels are higher in number than the CD34-positive microvessels in the CSDH inner membrane than in the outer membrane. Ultrastructural observations highlight the presence of a chronic inflammatory state mainly in the CSDH inner membrane. Integrating these results, we have obtained an etiopathogenetic model of CSDH. Cortical atrophy appears to be the triggering factor activating the cascade of transendothelial cellular filtration, inflammation, membrane formation and neovascularisation leading to the CSDH formation.

Treatment of giant intracranial aneurysms: long-term outcomes in surgical versus endovascular management

Aneurysms with a major diameter > 25 mm are defined as giant intracranial aneurysms (GIAs). Different clinical, pathological, and radiological factors were revealed as playing a role in choosing the best strategy between surgical and endovascular approaches. Despite the improvement of both techniques, the efficacy and safety of these different management are still debated. We evaluated the differences in clinical and radiological outcomes of GIAs treated with surgical and endovascular techniques in a large retrospective mono-centric study. We compared aneurysm location, clinical, morphological features, treatment outcome, and complications on the ground of treatment technique. The final cohort consisted of 162 patients. All the patients were assigned on the ground of the type of eligible treatment: surgical (118 patients) and endovascular procedure (44 patients). The different treatment strategies were made through a multidisciplinary selection whereas clinical parameters, location, and morphologic features of the aneurysm were considered. The surgical group manifested a greater reduction in performance levels and neurological status in the post-operative phases than the endovascular group (p < 0.01) with a higher incidence of complications (p = 0.012) in contrast to a lower recurrence rate (p > 0.01). There is no significant difference in post-operative mortality and survival between surgical and endovascular groups. The surgical group manifested a higher incidence of complications after treatment. The endovascular group has a better post-operative outcome, but a higher risk of recurrence and the necessity of further treatment.

Casemix, management, and mortality of patients rreseceiving emergency neurosurgery for traumatic brain injury in the Global Neurotrauma Outcomes Study: a prospective observational cohort study

BACKGROUND

Traumatic brain injury (TBI) is increasingly recognised as being responsible for a substantial proportion of the global burden of disease. Neurosurgical interventions are an important aspect of care for patients with TBI, but there is little epidemiological data available on this patient population. We aimed to characterise differences in casemix, management, and mortality of patients receiving emergency neurosurgery for TBI across different levels of human development.

METHODS

We did a prospective observational cohort study of consecutive patients with TBI undergoing emergency neurosurgery, in a convenience sample of hospitals identified by open invitation, through international and regional scientific societies and meetings, individual contacts, and social media. Patients receiving emergency neurosurgery for TBI in each hospital's 30-day study period were all eligible for inclusion, with the exception of patients undergoing insertion of an intracranial pressure monitor only, ventriculostomy placement only, or a procedure for drainage of a chronic subdural haematoma. The primary outcome was mortality at 14 days postoperatively (or last point of observation if the patient was discharged before this time point). Countries were stratified according to their Human Development Index (HDI)-a composite of life expectancy, education, and income measures-into very high HDI, high HDI, medium HDI, and low HDI tiers. Mixed effects logistic regression was used to examine the effect of HDI on mortality while accounting for and quantifying between-hospital and between-country variation.

FINDINGS

Our study included 1635 records from 159 hospitals in 57 countries, collected between Nov 1, 2018, and Jan 31, 2020. 328 (20%) records were from countries in the very high HDI tier, 539 (33%) from countries in the high HDI tier, 614 (38%) from countries in the medium HDI tier, and 154 (9%) from countries in the low HDI tier. The median age was 35 years (IQR 24-51), with the oldest patients in the very high HDI tier (median 54 years, IQR 34-69) and the youngest in the low HDI tier (median 28 years, IQR 20-38). The most common procedures were elevation of a depressed skull fracture in the low HDI tier (69 [45%]), evacuation of a supratentorial extradural haematoma in the medium HDI tier (189 [31%]) and high HDI tier (173 [32%]), and evacuation of a supratentorial acute subdural haematoma in the very high HDI tier (155 [47%]). Median time from injury to surgery was 13 h (IQR 6-32). Overall mortality was 18% (299 of 1635). After adjustment for casemix, the odds of mortality were greater in the medium HDI tier (odds ratio [OR] 2·84, 95% CI 1·55-5·2) and high HDI tier (2·26, 1·23-4·15), but not the low HDI tier (1·66, 0·61-4·46), relative to the very high HDI tier. There was significant between-hospital variation in mortality (median OR 2·04, 95% CI 1·17-2·49).

INTERPRETATION

Patients receiving emergency neurosurgery for TBI differed considerably in their admission characteristics and management across human development settings. Level of human development was associated with mortality. Substantial opportunities to improve care globally were identified, including reducing delays to surgery. Between-hospital variation in mortality suggests changes at an institutional level could influence outcome and comparative effectiveness research could identify best practices.

FUNDING

National Institute for Health Research Global Health Research Group.

Sacral Nerves Reconstruction After Surgical Resection of a Large Sacral Chordoma Restores the Urinary and Sexual Functionality and the Anal Continence

Objective

Chordomas are slow-growing tumors, with a high tendency to local relapse. En bloc resection is related to the most favorable outcome in terms of survival but is frequently associated with permanent neurological deficits involving sphincters and sexual functions. In the present article, we describe an innovative technique of en bloc resection followed by reconstruction of the sacral nerves with nerve grafts.

Methods

The chordoma was excised through a posterior approach after dividing the proximal and distal sacral nerves using the established technique. After that, a microsurgical S2-S3-S4 nerve reconstruction was performed connecting the proximal and distal stumps with sural nerve grafts withdrawn from both lower limbs.

Results

Immediately after surgery, the patient experienced complete impairment of sexual function and sphincters with urinary and fecal incontinence. After 6 months, there was a progressive recovery of sexual function and sphincter control. One year after the operation, the patient achieved an adequate sexual life (erection and ejaculation) and complete control of the bladder and anal sphincter.

Conclusion

Reconstruction of nerves sacrificed during sacral tumor removal has been shown to be effective in restoring sphincter and sexual function and is a promising technique that may significantly improve patients' quality of life.

Vascular intracranial malformations and dementia: An under-estimated cause and clinical correlation. Clinical note

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Cerebrovascular malformations (CVMs) such as arteriovenous malformations (AVMs) or dural arteriovenous fistulas (DAVFs) in addition to hemorrhagic presentation or focal neurological deficit, may manifest with global brain dysfunction resulting in dementia.

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Dementias secondary to CVMs constitute a probably underestimated subpopulation of patients of great interest because they present with devastating but potentially reversible cognitive impairment.

Cerebrovascular malformations (CVMs) such as arteriovenous malformations (AVMs) or dural arteriovenous fistulas (DAVFs) represent a possible source of intracranial hemorrhage, but these malformations can also manifest with neurologic disorders secondary to ischemic penumbra from vascular steal. In the latter case, the clinical manifestations are less obvious and characteristic, and may include a varied clinical spectrum ranging from focal deficits to generalized malfunction of the brain parenchyma resulting in dementia. Dementias secondary to CVMs constitute a probably underestimated subpopulation of patients of great interest because they present with devastating but potentially reversible cognitive impairment. We examined the pertinent literature regarding the clinical manifestations of CVMs characterized by cognitive impairment and describe the distinctive clinical features. Our results confirm that cognitive impairment is one of the clinical manifestations of CVMs and is a frequently misrecognized and often late-diagnosed cause of reversible dementia.

Far lateral lumbar disc herniation part 1: Imaging, neurophysiology and clinical features

Far lateral lumbar disc herniations (FLLDH) represent a separate category of disc pathology which includes both intraforaminal and extraforaminal lumbar disc herniations, that are characterized by a peculiar clinical presentation, diagnostic and treatment modalities as compared to the more frequent median and paramedian disc hernias. Surgical treatment often represents the only effective weapon for the cure of this disease and over the years different approaches have been developed that can reach the region of the foramen or external to it, with different degrees of invasiveness. The diagnosis is more demanding and still underestimated as it requires a more detailed knowledge in the spine anatomy and dedicated radiological studies. Computerized tomography and in particular magnetic resonance imaging are the appropriate tools for the diagnosis of FLLDH. Despite the widespread use of these diagnostic tests, many cases of FLLDH are overlooked due to insufficiently detailed radiological examinations or due to the execution of exams not focused to the foraminal or the extraforaminal region. Neurophysiological studies represent a valid aid in the diagnostic classification of this pathology and in some cases they can facilitate the differential diagnosis with other types of radiculopathies. In the present study, a comprehensive review of the clinical presentation, epidemiology, radiological study and the neurophysiological aspects is presented.

Ameloblastoma and Intracranial Involvement: The Current Challenge of the Radical Surgical Treatment. Comprehensive Review of the Literature and Institution experience

Background

Ameloblastoma (AMBL) is an odontogenic tumor, considered to be benign, but aggressive, whose principal risk is a recurrence. The growth can be enormous, and it can extend into the intracranial compartment with serious consequences.

Purpose

The intracranial involvement of AMBL is rare, and it may require an extensive surgery. Although it is a rare condition for the neurosurgeon to treat, knowing this condition can lead to a significant increase in survival for these patients.

Methods

A case of a 56-year-old woman presented with a history of recurrent left maxilla AMBL with intracranial extension and dural involvement of the anterior and medial cranial fossa is reported, followed by a systematic review of the literature with the aim to identify the best surgical treatment.

Results

A total of 32 cases were included in the qualitative analysis. Management is varied and often not described, resulting in an almost complete lack of information and indications for treatment. Radical surgery tends to yield the best outcomes, and it is recommended to have adequate surgical margins when possible.

Conclusions

Intracranial involvement from AMBL compartment is an uncommon manifestation of this rare pathology, but which deserves to be treated in a multidisciplinary way in order to ensure maximum surgical radicality. Recurrence reflects failure of the primary surgical resection. If recurrence is the major consideration, surgeons are encouraged to select radical surgery. Whenever a follicular-type maxillary AMBL is diagnosed, it is advisable to check for intracranial spreading and distant metastases during follow-up.

A rare case of Meckel's cave primary lymphoma: a case report and elaboration of the diagnostic algorithm

Management of lesions involving Meckel's cave can represent a challenge for neurosurgeons, because of the deep-seated location and the surrounding complex neurovascular structures. Very small lesions arising from MC are generally asymptomatic and radiological follow-up with head MRI and PET-CT is sufficient to control these lesions. In rare cases, the rapid increase in the size of lesions and the alteration of the neurologic status make early histological characterization mandatory in the plethora of lesions arising from Meckel's cave; a very small percentage is represented by central nervous system lymphomas. Primary diffuse large B-cell lymphoma is the most commonly found. Aggressive surgery, in case of suspicious Meckel's cave lesions, is strongly discouraged, because this procedure may increase the risk of postoperative deficit and provides no survival benefit compared with biopsy alone. The aim of the present paper is to report a very rare case of primary Meckel's cave diffuse large B-cell lymphoma (only seven cases were described in literature) and standardize an operative algorithm to avoid the risks of an incorrect surgical conduct.

Dorsal epidural "Spindle Cell Lipoma" in a pregnant female

Background

Spindle cell lipoma (SCL) constitutes just 1.5% of all lipomatous tumors. They typically occur in the upper back and shoulders. Here, we report a 37-year-old female presenting with a SCL in the dorsal epidural thoracic spine, during her 9^th month of pregnancy.

Case Description

A 37-year-old female presented with a subacute (2 months) progressive paraparesis during her ^9th month of pregnancy. The MR showed a dorsal epidural mass at the D8 level. Following a cesarean section, the patient underwent a laminectomy for tumor excision. Microscopically, the lesion proved to be a SCL. At 5-year follow-up, there was no tumor recurrence.

Conclusion

SCL represents a variant of benign lipomas that may occur in the dorsal thoracic spine. Gross total excision may be followed by a benign clinical course without recurrence or malignant degeneration. Very atypical SCLs need closer follow-up to avoid the misdiagnosis of liposarcoma.

Trigeminal Neuralgia Secondary to Intracranial Neoplastic Lesions: a Case Series and Comprehensive Review

It is known that intracranial tumors may trigger trigeminal neuralgia (TN) in some patients although the exact prevalence and occurrence is not completely defined yet. In the present study, we present a case series of patients with brain tumor and a clinical diagnosis of TN as the first and main manifestation of the disease. A retrospective analysis was performed involving patients diagnosed with brain tumor whose exclusive clinical feature our department focused on was TN. In addition, a review of all published cases was performed. From January 2017 to November 2018, 718 patients with brain tumor were admitted to our department, 17 of which suffered of TN, of which 8 patients presented with at least another neurologic symptom and 9 patients presented with TN alone, with typical symptoms of stubbing electric pain in 6 cases. In our series, we found that 2.3% of patients admitted for brain tumors had TN. In 0.8% of cases, TN was the main clinical symptom. The prevalence of tumor lesion in patients with facial neuropathic pain is not defined, but it is a well-known recognized initial symptom; however, early cerebral magnetic resonance imaging (MRI) is not yet strongly recommended in patients with newly diagnosed trigeminal neuralgia. The purpose of this article is, especially in unusual cases, to show that the application of such MR techniques and preoperative evaluation may contribute to diagnosis, indication, and surgery planning.

Intracranial capillary hemangiomas: literature review in pediatric and adult population

Capillary hemangiomas (CHs) of the central nervous system represent a rare diagnosed pathology. CHs are benign vascular tumors whose most common manifestations are dermal and mucous and mainly occur during childhood or adolescence, while the involvement of the central nervous system can occur in a wider age range. We conducted a PubMed research on literature published until March 2020. We only enrolled cases with histological documented presence of intracranial CH. For every case collected, we analyzed age, sex, localization, neuroimaging studies performed, the presence of extracranial CHs, symptoms, neurological deficits, extent of surgical resection (biopsy, partial or gross total), adjunct treatment received (radiotherapy, chemotherapy, Trans-Arterial Embolization TAE), and outcome. Up to March 2020, the literature review identified 52 cases to which we added the case of our personal experience. The mean age was 26 with slightly female prevalence (28 F, 25 M). The most common presenting symptom was headache (21 cases, 40%). The surgical treatment consisted of biopsy in 7 cases (13%), partial resection in 10 cases (19%), gross total resection in 31 cases (58.5%), biopsy followed by total resection in 2 cases (3%), and partial resection followed by total resection in 1 case (1.5%), and the diagnosis was obtained from an autopsy sample in 1 case (1.5%). For symptomatic lesions, surgery is a valid option to obtain histological characterization, neurological improvement, and where possible a total resection. Stereotactic radiotherapy can be used if the lesion is not surgically approachable or as an adjuvant treatment in case of partial resection, having shown good results in terms of long-term disease control.

Herpes Simplex Reactivation After Surgical Treatment of Trigeminal Neuralgia: A Retrospective Cohort Study

BACKGROUND

Herpes simplex virus (HSV) reactivation after surgery for trigeminal neuralgia has long been recognized. Only a few studies to date have focused on this complication, and its actual incidence remains unknown. The aim of this study was to investigate the incidence of postoperative herpes labialis (HL) in a cohort of patients treated with either percutaneous balloon compression or microvascular decompression to identify potentially significant differences between different treatments.

METHODS

A total of 92 patients who were operated on for TN with microvascular decompression (group A) or percutaneous balloon compression (group B) in the period 2010-2017 were retrospectively evaluated. The 2 subgroups of patients were compared according to history of previous HL and incidence of postoperative HL.

RESULTS

The final cohort comprised 56 male and 36 female patients. Average age was 58.50 years; 30 male patients belonged to group A and 26 male patients belonged to group B. Lifetime incidence of episodes of HL before surgery in 18/58 patients in group A (31.0%) and 12/34 patients in group B (35.3%), with no statistically significant difference among subgroups. Postoperatively, 1/56 patients in group A (1.7%) experienced HL compared 5/34 patients in group B (14.7%), with a strongly statistically significant difference between the 2 subgroups.

CONCLUSIONS

In our clinical experience, herpes simplex virus reactivation after surgery for trigeminal neuralgia is not so rare and is still not completely understood. Postoperative herpes simplex virus reactivation could be due to a direct mechanical injury on gasserian ganglion neurons, which is more common after percutaneous balloon compression.

The role of constitutive and inducible nitric oxide synthase in the human brain after subarachnoid hemorrhage

AIM

Results of prior experimental studies show that nitric oxide (NO) plays an important role in the pathogenesis of vasospasm. In the present study, the expression of endothelial NO synthase (eNOS), neuronal NO synthase (nNOS) and of inducible NO synthase (iNOS) in the human brain after subarachnoid haemorrhage were studied.

METHODS

Twenty-three samples of gyrus rectus or temporal operculum that were obtained during a surgical approach to anterior circulation aneurysms were used for this study. Seven samples were obtained during surgery from patients who underwent operation for unruptured aneurysms (control group). eNOS-mRNA, nNOS-mRNA and iNOS-mRNA were extracted and amplified by RT-PCR. Patients were subdivided for intergroup comparison by: age < 60 / > 60 years; source of sample; clinical grading; extent of subarachnoid clot; presence of intracerebral/intraventricular hematoma; surgical timing; vasospasm; outcome.

RESULTS

There was a significant increase in the expression of eNOS between SAH and control groups (P=0.046); eNOS hyperexpression was higher in the patients in poor clinical conditions (P=0.002) and lasted until the late phase of haemorrhage. nNOS overall expression was unchanged but hyperexpression was observed in the patients in poor clinical conditions (P=0.008). There was a significant hyperexpression of iNOS in SAH group (P=0.026), and in patients with vasospasm (P=0.0024); the expression was significantly reduced in the late phase of haemorrhage (P=0.0038).

CONCLUSIONS

The acute decrease of NO after SAH is not determined by reduced constitutive NOS expression and iNOS induction is a consequence of SAH and plays a major role in the pathogenesis of vasospasm.

α-Bisabolol, a nontoxic natural compound, strongly induces apoptosis in glioma cells

In this study, alpha-bisabolol, a sesquiterpene alcohol present in natural essential oil, was found to have a strong time- and dose-dependent cytotoxic effect on human and rat glioma cells. After 24 h of treatment with 2.5-3.5 microM alpha-bisabolol, the viability of these cells was reduced by 50% with respect to untreated cells. Furthermore, the viability of normal rat glial cells was not affected by treatment with alpha-bisabolol at the same concentrations as above. Glioma cells treated with high concentration of alpha-bisabolol (10 microM) resulted in a 100% cell death. Judging from hypo-G1 accumulation, poly(ADP-ribose) polymerase cleavage, and DNA ladder formation, the cytotoxicity triggered by alpha-bisabolol resulted from apoptosis induction. Moreover, the dissipation of mitochondrial-inner transmembrane potential and the release of cytochrome c from mitochondria indicated that, in these glioma cells, apoptosis occurred through an intrinsic pathway. As pointed out by the experimental results, alpha-bisabolol may be considered a novel compound able to inhibit glioma cell growth and survival.