The anatomic study and surgical technique for canal decompression with "pedicle-plasty" strategy in lumbar burst fractures with pedicle rupture

In the treatment of lumbar burst fractures with nerve injury, fusion is often required to rebuild spinal stability, but it can lead to the loss of motor units and increase the occurrence of adjacent segment diseases. Thus, a novel approach of lumbar canal decompression with "pedicle-plasty" strategy (DDP) was needed in clincal treatment. Firstly, image measurement analysis, the images of 60 patients with lumbar spine CT examinations were selected to measure osteotomy angle (OA), distance from the intersection of osteotomy plane and skin to the posterior midline (DM),transverse length of the osteotomy plane (TLOP), and sagittal diameter of the outer edge of superior articular process (SD). Secondary, cadaver study, distance between the intermuscular space and midline (DMSM), anterior and posterior diameters of the decompression (APDD), and lateral traction distance of the lumbosacral plexus (TDLP) were measured on 10 cadaveric specimens. Finally, procedure of DDP was demonstrated on cadaver specimens. OA ranged from 27.68°+4.59° to 38.34°+5.97°, DM ranged from 43.44+6.29 to 68.33+12.06 mm, TLOP ranged from 16.84+2.19 to 19.64+2.36 mm, and SD ranged from 22.49+1.74 to 25.53+2.21 mm. DMSM ranged from 45.53+5.73 to 65.46+6.43 mm. APDD were between 10.51+3.59 and 12.12+4.54 mm, and TDLP were between 3.28+0.81 and 6.27+0.62 mm.DDP was successfully performed on cadaveric specimens. DDP, as a novel approach of decompression of burst fractures with pedicle rupture, can fully relieve the occupation and at the same time preserve the spinal motor unit because of no resection of intervertebral discs and no destruction of facet joints,and has certain developmental significance.

Perispinal etanercept stroke trial design: PESTO and beyond

INTRODUCTION

Perispinal etanercept (PSE) is an innovative treatment designed to improve stroke recovery by addressing chronic post-stroke neuroinflammation. Basic science evidence, randomized clinical trial (RCT) evidence and 14 years of favorable clinical experience support the use of PSE to treat chronic stroke. This article provides guidance for the design of future PSE RCTs in accordance with current FDA recommendations.

AREAS COVERED

Scientific background and essential elements of PSE RCT design.

EXPERT OPINION

Intimate familiarity with PSE, its novel method of drug delivery, and the characteristics of ideal enriched study populations are necessary for those designing future PSE stroke trials. The design elements needed to enable a PSE RCT to generate valid results include a suitable research question; a homogeneous study population selected using a prospective enrichment strategy; a primary outcome measure responsive to the neurological improvements that result from PSE; trialists with expertise in perispinal delivery; optimal etanercept dosing; and steps taken to minimize the number of placebo responders. RCTs failing to incorporate these elements, such as the PESTO trial, are incapable of reaching reliable conclusions regarding PSE efficacy. SF-36 has not been validated in PSE trials and is unsuitable for use as a primary outcome measure in PSE RCTs.

Surgical corridors to foramen magnum meningiomas: a mini-review

Gross-total resection of foramen magnum meningiomas remains the gold standard of treatment and should be performed whenever possible. The transcondylar approach (and its variations) represents the most used approach for meningiomas located in the lateral or anterior borders of the foramen magnum. Endoscopic transclivus approaches represent a useful option in selected cases of anterior midline foramen magnum meningiomas, to be performed in centers with advanced experience in endoscopic skull base surgery, with the caveats of increased risk of postoperative cerebrospinal fluid leak. Alternatively, radiosurgery remains an option for well-selected cases, especially for the management of asymptomatic patients with small enlarging tumors. Advances in molecular profiling, as well as genetic analysis, may guide adjuvant treatment.

A Novel Direct Pathway of Dural Venous Outflow from the Basilar Venous Plexus via the Diploic Space of the Clivus

BACKGROUND

The internal jugular vein (IJV) is the pre-eminent outflow of the dural venous sinuses (DVS) in the supine position, while the vertebral venous plexus (VVP) dominates venous outflow in the upright position. Emissary veins can also be an accessory pathway for this venous egress. To our knowledge, alternative dural venous sinus directly drainage via the diploic space has not been previously reported in the literature.

METHODS

Ten fresh frozen adult cadavers underwent exposure of the basilar venous plexus. The entire plexus, still adhered to the underlying clivus, was removed with its underlying bone and submitted for histological examination following decalcification (Masson Trichrome, 5 μm slices).

RESULTS

All specimens were found to have direct communication between the basilar venous plexus and underlying diploic space of the clivus i.e., no intermediate clival emissary vein. These were concentrated near the midline and were more numerous over the clivus near the junction of the occipital and sphenoid bones. The endothelium of the venous sinus was continuous at the opening into the diploic space and these openings ranged in size from 500 to 750 μm (mean 650 μm).

CONCLUSIONS

An improved understanding of the cerebral venous drainage can assist clinicians and surgeons in recognizing normal, pathologic, and variant anatomy in this region. Based on our study, direct venous sinus (DVS) to diploic space drainage offers an additional pathway for venous egress from the intracranium. Therefore, removal of the dura over the clivus during various skull base procedures might be associated with increased venous bleeding from the basilar venous plexus on its deep surface where it interfaces with the clivus.

Angiographic Evaluation of Cranial Venous Outflow Patterns in Patients With and Without Idiopathic Intracranial Hypertension

BACKGROUND

Several collateral venous pathways exist to assist in cranial venous drainage in addition to the internal jugular veins. The important extrajugular networks (EJN) are often readily identified on diagnostic cerebral angiography. However, the angiographic pattern of venous drainage through collateral EJN has not been previously compared among patients with and without idiopathic intracranial hypertension (IIH).

OBJECTIVE

To quantify EJN on cerebral angiography among patients both with and without IIH and to determine whether there is a different EJN venous drainage pattern in patients with IIH.

METHODS

Retrospective imaging review of 100 cerebral angiograms (50 IIH and 50 non-IIH patients) and medical records from a single academic medical center was performed by 2 independent experienced neuroendovascular surgeons. Points were assigned to EJN flow from 0 to 6 using an increasing scale (with each patient's dominant internal jugular vein standardized to 5 points to serve as the internal reference). Angiography of each patient included 11 separately graded extrajugular networks for internal carotid and vertebral artery injections.

RESULTS

Patients in the IIH group had statistically significant greater flow in several of the extrajugular networks. Therefore, they preferentially drained through EJN compared with the non-IIH group. Right transverse-sigmoid system was most often dominant in both groups, yet there was a significantly greater prevalence of codominant sinus pattern on posterior circulation angiograms.

CONCLUSION

Patients with IIH have greater utilization of EJN compared with patients without IIH. Whether this is merely an epiphenomenon or possesses actual cause-effect relationships needs to be determined with further studies.

Nuance in Craniovertebral Junction Surgical Approach for Posterior C1-C2 Harms Stabilization: "Window Transposition" of the External Vertebral Venous Plexus for Bloodless C1 Lateral Mass Screw Insertion: Anatomical Aspects and Technical Notes

Atlas and axis instrumentation may be necessary in cases of several craniocervical junction pathologies. According to the Harms technique, C1-C2 polyaxial screws are inserted respectively in the C1 lateral masses and in C2 pedicles. C1 lateral mass screw insertion requires the careful subperiosteal dissection of the posterior elements of C1, the identification of the screw entry point by the downward distraction of C2 nerve root, and the cautious sparing of the overlying posterior external vertebral venous plexus (peVVP), whose bleeding, obstructing the surgical field, is sometimes barely controlled by hemostatic agents and swabbing. The authors describe in detail the anatomical aspects of an alternative surgical technique developed for the microsurgical transposition of the C1-C2 interposed external vertebral venous plexus in the case of Harms C1-C2 screw stabilization. The longitudinal median incision of the atlantoaxial membrane, followed by bilateral subperiosteal dissection and microsurgical section respectively at the inferior borders of the C1 laminae and at the superior borders of the C2 laminae, allows, as a "window opening," the symmetrical mediolateral transposition of the peVVP. This procedure provides a faster and cleaner anatomical exposition of the posterior surface of the C1 lateral mass and the C2 isthmus, preventing troublesome intraoperative venous bleeding that hinders C1 lateral mass screw insertion.

Extracranial prevertebral venous network of the craniocervical junction: CT-digital subtraction venography analysis

PURPOSE

Although the craniocervical junction has a complex anatomical structure associated with clinical diseases, its ventral venous network has not been well studied. This study aimed to clarify the extracranial ventral venous structure at the craniocervical junction.

METHODS

Head computed tomography digital subtraction venography (CT-DSV) images of 273 patients (age 6 months to 93 years) taken at our department were retrospectively analyzed. We analyzed the frequency and anatomical features of the venous channels, as well as their upstream and downstream connections with the surrounding channels at the ventral craniocervical junction, from the level of the hypoglossal canal to the second cervical vertebra.

RESULTS

In 54% of the cases, the vein descended from the anterior condylar confluence, running medially along the basioccipital and fusing with its counterpart in the midline at the level of the atlanto-occipital membrane. Furthermore, 24% of this vein was connected caudally to the anterior external vertebral venous plexus. We also identified venous channels, either as a sole vein or venous plexus, on the tip of the odontoid process (10%), which has not been well described previously. The vein around the odontoid process was connected to several veins, including the aforementioned vein anterior to the condyle and the anterior internal vertebral venous plexus.

CONCLUSIONS

CT-DSV analysis revealed a detailed venous architecture ventral to the craniocervical junction. Venous structures identified in this study may be involved in diseases in this area.

Evidence for the Vascular Origin of Benign Enhancing Foramen Magnum Lesions via Intraoperative Photographs: Case Report and Review of the Literature

A small, benign enhancing lesion posterior to the intracranial vertebral artery at the foramen magnum is a recently described image-based entity and believed to represent varix or ganglion. We report on an individual who underwent surgery due to a hybrid neurofibroma/schwannoma of the trigeminal nerve and additionally presented a small gadolinium-enhancing lesion in the right spinal canal at the level of the craniocervical junction (CCJ). The intraoperative finding of this enhancing lesion most likely represents the lateral internal vertebral venous plexus which does not require follow up or surgical excision.

Cannabis Abuse and Perioperative Complications Following Inpatient Spine Surgery in the United States

MINI

Due to its complicated legal status, the effects of cannabis on elective spine surgery patients have not been well studied. In this nationwide analysis, we find that cannabis abuse is associated with higher perioperative thromboembolism and neurologic complications, respiratory complications, sepsis, length of stay, hospital charges, and rates of unfavorable discharge disposition.

Venous structures can mimic masses in the foramen magnum

Benign enhancing lesions at the foramen magnum is a recently described entity and believed to represent a varix or ganglion. These lesions are typically described as being single, located posterior to the intradural vertebral artery, and not attached to the dura. These 2 cases demonstrate previously undescribed variations in appearance of these lesions including contacting the posterior inferior cerebellar artery and lateral epidural plexus/dura, segmental dilatations, transverse and linear configuration, and visualization on an unenhanced CT head. These lesions most likely reflect bridging veins and are structures that clinicians should be aware of to avoid unnecessary follow-up or surgical intervention.

Transvenous embolization for craniocervical junction epidural arteriovenous fistula with a pial feeder aneurysm

Arteriovenous fistulas at the craniocervical junction are rare vascular malformations with frequent hemorrhagic presentations, which may have a concurrent pial feeder aneurysm. A 65-year-old man presented with subarachnoid hemorrhage and angiography showed an epidural arteriovenous fistula at the C-2 level with an anterior spinal feeder aneurysm without perimedullary venous drainage. Transarterial coil embolization of the ruptured aneurysm and partial Onyx embolization of the shunt led to thrombosis of the aneurysm. However, three years later angiography showed an increased shunt flow and recurrence of the aneurysm. Transvenous embolization of the shunt using coils and Onyx yielded complete obliteration of the shunt, thus leading to occlusion of the aneurysm. This case demonstrates that partial transarterial embolization of arteriovenous fistula leaves a risk of rebleeding, whereas complete obliteration of the shunt with a transvenous approach can lead to disappearance of the flow-related aneurysm without embolization of the aneurysm itself.

Posterior occipital intramuscular hemangioma mimicking arteriovenous malformation: Case report

RATIONALE

Intermuscular hemangioma (IH) usually occurs in the muscles of the limbs and trunk, but can rarely occur in the occipital region. IH in the occipital region is easily misdiagnosed as arteriovenous malformation (AVM).

PATIENT CONCERNS

A 31-year-old woman had a right occipital mass for 5 months without pulsation.

DIAGNOSIS

Head computered tomography angiography (CTA) and digital substraction angiography (DSA) examinations showed that the lesion was mainly vascular, approximately 3 × 5 cm in size, and supplied by occipital arteries and the muscular branches of vertebral arteries. The venous drainage of the lesions communicated with the suboccipital vein plexus and the paravertebral vein in the venous phase, indicating AVM. Postoperative histological investigation showed the lesion was a hemangioma.

INTERVENTIONS

It was recommended for surgical removal. The surgery was carried out under general anesthesia. The lesion showed a clear boundary. The occipital artery touched the anterior margin of the lesion, was exposed and ligated, and was removed around the lesion. The lesion consisted of massive blood vessels, and the surrounding muscles were swollen, indicating IH.After the lesion was removed, the normal muscle tissue around the lesion was also removed.

OUTCOMES

The patient achieved a good recovery after surgery, and pathology confirmed IH. A postoperative 1-year CTA review was performed and showed partial residual, then the radiotherapy was recommended. She refused further radiotherapy, follow-up 2 years later showed no enlargement of the lesion.

LESSONS

Although IH rarely occurs in the occipital region, this can occur. Due to the complexity of the drainage veins in the occipital region, these IH are prone to misdiagnosis as AVM.

Therapeutic implications of how TNF links apolipoprotein E, phosphorylated tau, α-synuclein, amyloid-β and insulin resistance in neurodegenerative diseases

While cytokines such as TNF have long been recognized as essential to normal cerebral physiology, the implications of their chronic excessive production within the brain are now also increasingly appreciated. Syndromes as diverse as malaria and lead poisoning, as well as non‐infectious neurodegenerative diseases, illustrate this. These cytokines also orchestrate changes in tau, α‐synuclein, amyloid‐β levels and degree of insulin resistance in most neurodegenerative states. New data on the effects of salbutamol, an indirect anti‐TNF agent, on α‐synuclein and Parkinson's disease, APOE4 and tau add considerably to the rationale of the anti‐TNF approach to understanding, and treating, these diseases. Therapeutic advances being tested, and arguably useful for a number of the neurodegenerative diseases, include a reduction of excess cerebral TNF, whether directly, with a specific anti‐TNF biological agent such as etanercept via Batson's plexus, or indirectly via surgically implanting stem cells. Inhaled salbutamol also warrants investigating further across the neurodegenerative disease spectrum. It is now timely to integrate this range of new information across the neurodegenerative disease spectrum, rather than keep seeing it through the lens of individual disease states.

Dural arteriovenous fistula of the lateral foramen magnum region: A review

The lateral foramen magnum region is defined as the bilateral occipital area that runs laterally up to the jugular foramen. The critical vasculatures of this region are not completely understood. Dural arteriovenous fistulas that occur in this region are rare and difficult to treat. Therefore, we searched PubMed to identify all relevant previously published English language articles about lateral foramen magnum dural arteriovenous fistulas, and we performed a review of this literature to increase understanding about these fistulas. Four types of dural arteriovenous fistulas occur in the lateral foramen magnum region. These include anterior condylar confluence and anterior condylar vein dural arteriovenous fistulas, posterior condylar canal dural arteriovenous fistulas, marginal sinus dural arteriovenous fistulas, and jugular foramen dural arteriovenous fistulas. These dural arteriovenous fistulas share similar angioarchitectures and clinical characteristics. The clinical presentations of lateral foramen magnum dural arteriovenous fistulas include pulsatile tinnitus, intracranial hemorrhage, myelopathy, orbital symptoms, and cranial nerve palsy. Currently, head computed tomography, computed tomography angiography, magnetic resonance imaging, magnetic resonance angiography and digital subtraction angiography (DSA) are useful for diagnosing dural arteriovenous fistulas, and of these, DSA remains the "gold standard." Most lateral foramen magnum dural arteriovenous fistulas need to be treated due to their aggressive symptoms, and transvenous embolization presents the best options. During treatment, it is critical to accurately place the microcatheter into the fistula point, and intraoperative integrated computed tomography and DSA data are very helpful. Other treatments, such as transarterial embolization, microsurgery or conservative treatment, can also be chosen. After appropriate treatment, most patients with lateral foramen magnum dural arteriovenous fistulas achieve satisfactory outcomes.