Simple depressed skull fracture causing sagittal sinus stenosis and increased intracranial pressure: case report and review of the literature

Advanced Surgical Techniques for Dural Venous Sinus Repair: A Comprehensive Literature Review

The dural venous sinus (DVS) is a thin-walled blood channel composed of dura mater that is susceptible to injury during common neurosurgical approaches. DVS injuries are highly underreported, which is reflected by a lack of literature on the topic. Neurosurgeons should be familiar with appropriate techniques to successfully repair an injured DVS and prevent associated complications. This study presents a literature review on the surgical techniques for DVS repair after DVS injury during common neurosurgical approaches. The databases PubMed and Scopus were queried using the terms "cranial sinuses," "superior sagittal sinus," "transverse sinuses," "injury," and "surgery." A total of 117 articles underwent full-text review and were analyzed for surgical approach, craniotomy, lesion location, lesion characteristics, and surgical repair techniques. A literature review was performed, and a comprehensive summary is presented. Data from publications describing DVS lacerations related to pathological conditions (eg, meningioma) were excluded. A total of 9 techniques aiding with bleeding control, hemostasis, and sinus repair and reconstruction were identified, including compression, hemostatic agents, bipolar cautery, dural tenting and tack-up suturing, dural flap, direct suturing, autologous patch, venous bypass, and ligation. The advantages and drawbacks of each technique are described. Multiple options to treat DVS injuries are available to the neurosurgeon. Treatment type is based on anatomic location, complexity of the laceration, cardiovascular status, the presence of air embolism, and the dexterity and experience of the surgeon.

Neurosurgical Causes of Pulsatile Tinnitus: Contemporary Update

Traditionally in the domain of the otolaryngologist, pulsatile tinnitus (PT) has become increasingly relevant to neurosurgeons. PT may prove to be a harbinger of life-threatening pathology; however, often, it is a marker of a more benign process. Irrespectively, the neurosurgeon should be familiar with the many potential etiologies of this unique and challenging patient population. In this review, we discuss the myriad causes of PT, categorized by pulse-phase rhythmicity.

Rupture of the Superior Sagittal Sinus in Penetrating Head Injury-Management of a Rare Trauma Mechanism

Civilian penetrating head injury caused by foreign objects is rare in Germany (Europe), but can result in complex neurovascular damage. We report on a patient who in suicidal intent inflicted on himself a penetrating brain injury near the vertex with a captive bolt gun. A laceration at the junction of the middle to the posterior third of the superior sinus occurred by bolt and bone fragments leading to critical stenosis and subsequent thrombosis. Upon surgery, the proximal and distal sinus openings were completely thrombosed. The sinus laceration was closed by suture and the intraparenchymal bone fragments were retrieved. Postoperative angiography disclosed persistent occlusion of the superior sagittal sinus. The patient did not develop any symptoms due to venous congestion (edema, hemorrhage), suggesting sufficient collateral venous outflow. The patient completely recovered despite the complexity of the lesion.

Venous Injury in Patients with Blunt Traumatic Brain Injury: Retrospective Analysis of a National Cohort

BACKGROUND

Cerebral venous injury (CVI) includes injury to a dural venous sinus or major vein and leads to poorer outcomes for patients with blunt traumatic brain injury (TBI). We sought to identify the incidence, associated factors, and outcomes associated with CVI in a large national cohort.

METHODS

Adult patients with blunt TBI were identified from the National Trauma Databank (2013-2017). Outcomes included inpatient mortality, discharge disposition, stroke, length of stay (LOS), intensive care unit LOS, and duration of mechanical ventilation. Multivariate regression models were used to identify the association between exposure variables and CVI, as well as each outcome.

RESULTS

There were 619,659 patients with blunt TBI who met the inclusion criteria. CVI occurred in 1792 (0.3%) patients. Mixed intracranial injury type had the strongest association with CVI (odds ratio [OR] 2.89, 95% confidence interval [CI] 2.38-3.50), followed by isolated TBI (OR 1.76, 95% CI 1.54-2.02) and skull fracture (OR 1.72, 95% CI 1.55-1.91). CVI was associated with increased odds of mortality (OR 1.38, 95% CI 1.19-1.60), nonroutine discharge (OR 1.26, 95% CI 1.12-1.40), and stroke (OR 1.95, 95% CI 1.33-2.86). It was also associated with longer LOS (β 2.02, 95% CI 1.55-2.50) and intensive care unit LOS (β 0.14, 95% CI 0.13-0.16). Among locations of venous injury, superior sagittal sinus injury had significant associations with mortality (OR 2.93, 95% CI 1.62-5.30) and nonroutine discharge disposition (OR 1.94, 95% CI 1.12-3.35), whereas the others did not.

CONCLUSIONS

We identified a 0.3% incidence of CVI in all-comers with blunt TBI as well as several injury-related variables that may be used to guide investigation for dural venous sinus injury. CVI was associated with poorer outcomes, with superior sagittal sinus injury having the strongest association.

Shear behavior of human skull bones

A shear-punch test (SPT) experimental method was developed to address the lack of shear deformation and failure response data for the human skull as a function of local bone microarchitecture. Improved understanding of skull deformation and fracture under varying stress-states helps implement mechanism-based, multi-axial material models for finite element analysis for optimizing protection strategies. Shear-punch coupons (N = 47 specimens) were extracted from right-parietal and frontal bones of three fresh-frozen-thawed human skulls. The specimens were kept as full through-thickness or segmented into the three skull constituent layers: the inner and outer cortical tables and the middle porous diploë. Micro-computed x-ray tomography (μCT) before and after SPT provided the bone volume fraction (BVF) as a function of depth for correlation to shear mechanisms in the punched volumes. Digital image correlation was used to track displacement of the punch above the upper die to minimize compliance error. Five full-thickness specimens were subjected to partial indentation loading to investigate the process of damage development as a function of BVF and depth. It was determined that BVF dominates the shear yield and ultimate strength of human skull bone, but the imposed uniaxial loading rate (0.001 and 0.1 s^-1) did not have as strong a contribution (p = 0.181-0.806 > 0.05) for the shear yield and ultimate strength of the skull bone layer specimens. Shear yield and ultimate strength data were highly correlated to power law relationships of BVF (R² = 0.917-0.949). Full-thickness and partial loaded SPT experiments indicate the diploë primarily dictates the shear strength of the intact structure.

Intracranial Hypertension Following Gunshot Wound to the Torcula: Case Report and Literature Review

BACKGROUND

Elevation of bone for the treatment of depressed skull fractures overlying venous sinuses is rarely required or performed. The neurosurgical literature only describes a handful of cases of surgical intervention in which the posterior two-thirds of the superior sagittal sinus was involved. Clinical course is variable, signs and symptoms suggest increased intracranial pressure, and all conservative measures should be exhausted before proceeding with the surgical route.

CASE DESCRIPTION

A 27-year-old man presented with a self-inflicted gunshot wound to posterior head. On presentation, there were no neurologic complaints. On imaging, the bullet fragment was associated with a comminuted anteriorly displaced fracture over the torcula. Vessel imaging showed tapering of the superior sagittal sinus and transverse sinuses near the torcula, suggesting narrowing due to mass effect. The patient did not respond to initial conservative management and developed worsening diplopia and papilledema concerning for increased intracranial pressure. Occipital/suboccipital craniectomy was performed with elevation of depressed skull fracture, decompression of dural venous sinus, removal of bullet, and mesh cranioplasty. Repeat ophthalmology examination postoperatively showed improvement in optic disc edema and diplopia.

CONSLUSIONS

This case confirms that the approach of surgical management of superior sagittal venous sinus injuries associated with skull fractures described in the literature also can be used successfully for injuries over the torcula if conservative management does not help alleviate the symptoms and results in good outcome. It was felt that delayed surgery also plays an important role, as it gives time for scar tissue to form, which may help to protect the sinus from injury during surgery.

Treatment of Traumatic Depressed Compound Skull Fractures

BACKGROUND

A skull fracture widely occurs in patients with traumatic brain injury, leading to intracranial hematoma, brain contusion, and intracranial infection. It also influences the prognosis and death of patients. This study aimed to discuss cases of patients with comminuted skull fractures.

METHODS

From October 2015 to December 2018, 38 patients with comminuted skull fractures were admitted to the hospital. All patients underwent three-dimensional reconstruction of computed tomography scan images. Digital subtraction angiography or magnetic resonance venography was performed to find out the venous sinus. The clinical findings of the patients were significant regarding gender, age, injury mechanism, location, admission Glasgow Coma Scale (GCS), combined epidural, subdural, cerebral contusion, intracranial pneumatosis, maximum depth of depression, admission to surgery, dural tear, post-operative cerebrospinal fluid leakage, post-operative infection, and Glasgow Outcome Scale (GOS) 3 months after surgery.

RESULTS

The incidence of traffic accidents, fall from a height, railway accidents, fall of an object, and chop injury was 60.5%, 18.4%, 13.2%, 5.3%, and 2.6%, respectively. Intra-operative dural trar negatively correlated with epidural hematoma, cerebral contusion, and subdural hematoma. Also, post-operative infection negatively correlated with intracranial pneumatosis, depth of fracture depression, and pre-operative cerebrospinal fluid leakage. No correlation was found between contusion, subdural hematoma, intracranial pneumatosis, depth of fracture depression, and post-operative infection. The GOS score positively correlated with age, pre-operative cerebrospinal fluid leakage, and admission GCS score.

CONCLUSIONS

A perfect pre-operative examination is a key to successful surgery. Further studies should be conducted to find out more effective treatments for traumatic comminuted skull fractures.

Pediatric cerebral venous sinus thrombosis or compression in the setting of skull fractures from blunt head trauma

OBJECTIVE Pediatric cerebral venous sinus thrombosis has been previously described in the setting of blunt head trauma; however, the population demographics, risk factors for thrombosis, and the risks and benefits of detection and treatment in this patient population are poorly defined. Furthermore, few reports differentiate between different forms of sinus pathology. A series of pediatric patients with skull fractures who underwent venous imaging and were diagnosed with intrinsic cerebral venous sinus thrombosis or extrinsic sinus compression is presented. METHODS The medical records of patients at 2 pediatric trauma centers were retrospectively reviewed. Patients who were evaluated for blunt head trauma from January 2003 to December 2013, diagnosed with a skull fracture, and underwent venous imaging were included. RESULTS Of 2224 pediatric patients with skull fractures following blunt trauma, 41 patients (2%) underwent venous imaging. Of these, 8 patients (20%) had intrinsic sinus thrombosis and 14 patients (34%) displayed extrinsic compression of a venous sinus. Three patients with intrinsic sinus thrombosis developed venous infarcts, and 2 of these patients were treated with anticoagulation. One patient with extrinsic sinus compression by a depressed skull fracture underwent surgical elevation of the fracture. All patients with sinus pathology were discharged to home or inpatient rehabilitation. Among patients who underwent follow-up imaging, the sinus pathology had resolved by 6 months postinjury in 80% of patients with intrinsic thrombosis as well as 80% of patients with extrinsic compression. All patients with intrinsic thrombosis or extrinsic compression had a Glasgow Outcome Scale score of 4 or 5 at their last follow-up. CONCLUSIONS In this series of pediatric trauma patients who underwent venous imaging for suspected thrombosis, the yield of detecting intrinsic thrombosis and/or extrinsic compression of a venous sinus was high. However, few patients developed venous hypertension or infarction and were subsequently treated with anticoagulation or surgical decompression of the sinus. Most had spontaneous resolution and good neurological outcomes without treatment. Therefore, in the setting of pediatric skull fractures after blunt injury, venous imaging is recommended when venous hypertension or infarction is suspected and anticoagulation is being considered. However, there is little indication for pervasive venous imaging after pediatric skull fractures, especially in light of the potential risks of CT venography or MR venography in the pediatric population and the unclear benefits of anticoagulation.

Traumatic open depressed cranial fracture causing occlusion of posterior superior sagittal sinus: Case report

RATIONALE

The superior sagittal sinus (SSS) is the major dural sinuses that receive a considerable amount of venous drainage. Interruption of its posterior third has been suggested to cause intracranial hypertension and lead to potentially fatal consequences.

PATIENT CONCERNS

We presented a 22-year-old man with a severe headache and scalp bleeding after a head chop wound. Physical examination identified a 20-cm straight laceration in his parietooccipital scalp. Computed tomography (CT) demonstrated a depressed cranial fracture (DCF) in the left parietooccipital bone, a fracture line across the midline to the right side, and penetrations of bone fragments into the brain parenchyma.

DIAGNOSES

Traumatic open DCF in left parietooccipital bone.

INTERVENTIONS

An emergent left parietooccipital craniotomy, followed by cranioplasty to restore the depressed bone flap, was delivered to the patient. Postoperative CT confirmed successful elevation of the DCF and removal of intracerebral bone fragments. However, postoperative CT angiography (CTA) demonstrated an absence of venous flow distal to the fracture, suggesting occlusion of the posterior third of SSS. MRV revealed a persistent absence of venous flow in the posterior third of SSS with dilated cortical venous drainage. Anticoagulation treatment was initiated 3 days after surgery, and follow-up CTA and digital subtraction angiography showed gradually improved patency in the anterior and middle two-thirds of SSS.

OUTCOMES

Despite occlusion of the posterior third of SSS, patient's symptoms resolved after the operation and he was discharged without complications.

LESSONS

The favorable clinical outcome after complete occlusion of the posterior third of the SSS has rarely been reported and it might be explained by our timely surgical intervention and development of compensatory cerebral collateral circulation.

Midline depressed skull fracture presenting with quadriplegia: A rare phenomenon

Background:

Midline depressed skull fractures (MDSFs) deserve a special mention among skull fractures and should always be treated with caution. Here, an extremely unusual clinical presentation of a case of MDSF is highlighted along with its successful surgical management.

Case Description:

A 26-year-old male presented with quadriplegia following assault on the head with sharp weapons. The patient had multiple lacerated wounds on the scalp with underlying cranial fractures. On evaluation, computerized tomography (CT) of the brain showed a midline depressed skull fracture compressing the superior sagittal sinus (SSS) causing bilateral frontoparietal venous infarction. CT venogram showed a filling defect of the SSS due to the penetrating bone fragment. He underwent elevation of the depressed fracture and repair of the sinus with pericranial graft. Patient improved neurologically, and follow-up magnetic resonance venogram showed a patent SS.

Conclusion:

MDSF can present with quadriparesis/quadriplegia due to middle one-third SSS obstruction/thrombosis leading to bilateral motor cortical venous infarction. Such MDSFs may require emergent surgical elevation of the depressed bone fragment for restoration of the patency of the sinus.

Pediatric Traumatic Brain Injury: Characteristic Features, Diagnosis, and Management

Traumatic brain injury (TBI) is the leading cause of death and disability in children. Pediatric TBI is associated with several distinctive characteristics that differ from adults and are attributable to age-related anatomical and physiological differences, pattern of injuries based on the physical ability of the child, and difficulty in neurological evaluation in children. Evidence suggests that children exhibit a specific pathological response to TBI with distinct accompanying neurological symptoms, and considerable efforts have been made to elucidate their pathophysiology. In addition, recent technical advances in diagnostic imaging of pediatric TBI has facilitated accurate diagnosis, appropriate treatment, prevention of complications, and helped predict long-term outcomes. Here a review of recent studies relevant to important issues in pediatric TBI is presented, and recent specific topics are also discussed. This review provides important updates on the pathophysiology, diagnosis, and age-appropriate acute management of pediatric TBI.

Monro-Kellie 2.0: The dynamic vascular and venous pathophysiological components of intracranial pressure

For 200 years, the 'closed box' analogy of intracranial pressure (ICP) has underpinned neurosurgery and neuro-critical care. Cushing conceptualised the Monro-Kellie doctrine stating that a change in blood, brain or CSF volume resulted in reciprocal changes in one or both of the other two. When not possible, attempts to increase a volume further increase ICP. On this doctrine's "truth or relative untruth" depends many of the critical procedures in the surgery of the central nervous system. However, each volume component may not deserve the equal weighting this static concept implies. The slow production of CSF (0.35 ml/min) is dwarfed by the dynamic blood in and outflow (∼700 ml/min). Neuro-critical care practice focusing on arterial and ICP regulation has been questioned. Failure of venous efferent flow to precisely match arterial afferent flow will yield immediate and dramatic changes in intracranial blood volume and pressure. Interpreting ICP without interrogating its core drivers may be misleading. Multiple clinical conditions and the cerebral effects of altitude and microgravity relate to imbalances in this dynamic rather than ICP per se. This article reviews the Monro-Kellie doctrine, categorises venous outflow limitation conditions, relates physiological mechanisms to clinical conditions and suggests specific management options.

Improvement in venous outflow following superior sagittal sinus decompression after a gunshot wound to the head: case report

The most commonly described indications for surgical management of closed depressed skull fractures are hematoma evacuation and repair of extensive cosmetic deformity. Venous sinus injury, which occurs in a subset of depressed skull fractures, is not typically listed as an indication for surgical treatment due to the potential for major venous hemorrhage associated with surgery near these structures. However, if patients exhibit signs and symptoms of intracranial hypertension and radiographic findings demonstrate sinus compromise, surgical elevation of the depressed skull fragments is indicated. The authors present the case of a 25-year-old woman with a depressed skull fracture secondary to a gunshot wound with symptomatic compromise in venous outflow of the posterior one-third of the superior sagittal sinus. The patient was treated with surgical decompression via bilateral craniectomy along with intracranial pressure-lowering medical therapy and had almost full resolution of her presenting symptoms with documented improvement in flow through the superior sagittal sinus. While the use of surgical treatment for these types of injuries is highly debated, the authors demonstrate here that safe, effective surgical management of these patients is possible and that surgical decompression should always be considered in the case of symptomatic venous sinus flow obstruction.

Bizarre depressed skull fracture by a tile fragment in a young child, causing superior sagittal sinus injury

BACKGROUND

Head injuries following fall from height are not very uncommon in developing countries due to a lack of safety standards. We describe this bizarre injury by a tile fragment penetrating the superior sagittal sinus (SSS) and its successful surgical management.

CASE DESCRIPTION

A 7-year-old child presented with a tile fragment embedded in the skull, penetrating SSS. Urgent exploration and removal of the foreign body was done to prevent complications like infection and delayed development of intracranial hypertension. Although bleeding from the SSS was a problem, this was tackled by raising the head end and giving pressure with Surgicel and Gelatine sponge. This ensured a favorable outcome.

CONCLUSION

Although compound depressed fractures of the SSS are managed conservatively due to the risk of fatal venous hemorrhage, the unique nature of the injury in this case warranted surgical management. This case illustrates that even in such a scenario, adherence to neurosurgical principles can ensure a good outcome.

Intracranial hypertension caused by a depressed skull fracture resulting in superior sagittal sinus thrombosis in a pediatric patient: treatment with ventriculoperitoneal shunt insertion

OBJECT

Intracranial hypertension resulting from compression of the superior sagittal sinus (SSS) by an overlying depressed calvarial fracture is a rare condition. Primary surgical treatment for the symptomatic patient in this setting traditionally involves elevation of the fracture, which often carries significant associated morbidity.

METHODS

The authors report a case involving a 6-year-old boy who suffered a closed, depressed, parietooccipital fracture as the result of an unhelmeted all-terrain vehicle accident. This fracture caused compression and subsequent thrombosis of the SSS, which resulted in CSF malabsorption and progressive intracranial hypertension. Initially headache free following the injury, he had developed severe and unremitting headaches by postinjury Day 7. A CT angiography study of the head obtained at this time exhibited thrombosis of the SSS underlying the depressed calvarial fracture. Subsequent lumbar puncture demonstrated markedly elevated intrathecal pressures. Large volumes of CSF were removed, with temporary improvement in symptoms. After medical management with anticoagulation failed, the decision was made to proceed with image-guided ventriculoperitoneal shunt insertion.

RESULTS

The patient's headaches resolved immediately following the procedure, and anticoagulation therapy was reinstituted. Follow-up images obtained 4 months after the injury demonstrated evidence of resolution of the depressed fracture, with recanalization of the SSS. The anticoagulation therapy was then discontinued. To the authors' knowledge, this report is the first description of ventriculoperitoneal shunt insertion as the primary treatment of this infrequent condition.

CONCLUSIONS

This report demonstrates that select patients with this presentation can undergo CSF diversion in lieu of elevation of the depressed skull fracture-a surgical procedure shown to be associated with increased risks when the depressed fracture overlies the posterior SSS. The literature on this topic is reviewed and management of this condition is discussed.

Endoscopic and microscopic anatomy of the superior sagittal sinus and torcular herophili

Surgery of the superior sagittal sinus (SSS) is a challenging areas for neurosurgeons. To better understand the anatomy of the SSS, we examined the chordae and arachnoid granulations in the lumen of the SSS and torcular herophili with the aid of an endoscope and a microscope, and re-evaluated the role of the chordae Willisii in preventing blood backflow. We prepared 10 SSS from fresh human cadavers during autopsies. After the cranial vaults were removed, an endoscope was inserted into the lumen of the sinus to examine the structures and morphological features of the chordae Willisii, and the topographic distribution of the arachnoid granulations. The sinuses were subsequently opened using standard anatomical methods and the intraluminal structures of the dural sinus were subjected to microanatomic analysis. In another five formalin-embalmed cadaver heads, blue latex was injected from the posterior end of the SSSs to observe filling of the SSS tributaries. We identified three types of chordae in the lumen of the SSS: valve-like chordae (48.3% of all chordae), followed by trabecular (31.5%) and laminar (20.2%) chordae. The laminar chordae at the posterior end of the SSS divide the sinus into two separate channels of different sizes. Similar structures were also seen in the lumen of the torcular herophili. The majority of arachnoid granulations were found as digitations in the lumen at the lateral wall or lateral recess of the middle segment of the SSS. Microscopic examination of the intraluminal structures of the SSS confirmed endoscopic findings. In the injection test we found that the SSS tributaries could be filled retrogradely with artificial dye, suggesting that the function of valve-like chordae in preventing the backflow of blood is restricted only to physiological conditions. Thus, we could visualize and examine endoscopically the intact intraluminal structures of the SSS, which may have therapeutic or diagnostic significance.