Hormone Concentration Measurement in Intracranial Dural Arteriovenous Fistulae

OBJECTIVE

Intracranial dural arteriovenous fistulae (DAVFs) represent a subset of cerebral vascular malformations associated with significant morbidity and mortality. In Japan, DAVF exhibits sex-based differences in anatomical distribution, with female predominance in the cavernous sinus (CS) and male predominance in the transverse sinus (TS). Nevertheless, the pathophysiology of DAVF is not fully understood, and hormonal influences are hypothesized to play a role in its development. This study aimed to investigate changes in the concentrations of sex steroid hormones between intracranial and peripheral sampling sites in patients with CS- and TS-DAVF.

METHODS

We recruited 19 patients with CS-DAVF (n = 12) and TS-DAVF (n = 7) in this study. Blood hormone measurements were obtained from peripheral and jugular bulb samples during endovascular intervention. Hormone concentrations were analyzed using enzyme-linked immunosorbent assay kits, and statistical analyses were performed.

RESULTS

Our study revealed a higher prevalence of CS-DAVF in females and TS-DAVF in males, which is consistent with previous studies. Estradiol concentration was significantly lower in the jugular bulb compared with in the periphery in both patients with CS- and TS-DAVF. This decrease in estradiol was observed irrespective of the patient's sex and independent of follicle-stimulating hormone levels.

CONCLUSIONS

These findings indicate a local decrease in estradiol levels within the intracranial vasculature of patients with DAVF. This suggests a potential multifactorial role of estradiol in the pathomechanism of DAVFs, warranting further investigation to understand its influence on DAVF formation and potential targeted therapies, thereby enhancing patient outcomes.

Intensive care unit admission is not necessary after venous sinus stenting

BACKGROUND

Venous sinus stenting (VSS) has emerged as a safe and effective treatment option for idiopathic intracranial hypertension. Many physicians routinely admit patients to the intensive care unit (ICU) for close monitoring, but little data exists on whether this is necessary.

METHODS

Electronic medical records of consecutive patients who underwent VSS by the senior author from 2016 to 2022 at a single center were reviewed.

RESULTS

214 patients were included. The mean (SD) age was 35.5 (11.6) and 196 (91.6%) patients were female. A total of 166 (77.6%) patients underwent transverse sinus stenting alone; 9 (4.2%) underwent superior sagittal sinus (SSS) stenting alone, 37 (17.3) concomitant transverse and SSS stenting, and 2 (0.9%) underwent stenting at alternate sites. All patients were planned admission to the regular ward (27.6%) or day hospital (72.4%). Twenty (9.3%) patients were discharged to home the same day as the procedure and 182 (85%) patients were discharged the following day. Major periprocedural complications were identified in 2 (0.93%) patients and minor complications were identified in 16 (7.4%). Only one patient with a subdural hematoma identified in the post-anesthesia care unit (PACU) had care escalated to the ICU. No severe complications were identified after the PACU stay. During the next 48 hours after discharge, 4 (1.9%) patients returned to any emergency room to be evaluated without requiring readmission.

CONCLUSION

Routine ICU admission following uncomplicated VSS is unnecessary. Overnight admission to a low-acuity ward, or even same-day discharge in select patients, appears to be a safe and cost-effective strategy.

Dural Arteriovenous Fistula Mimicking Acute Encephalitis

We herein report a case of acute neurological symptoms and a fever initially suspected of being encephalitis but later revealed to be dural arteriovenous fistula (dAVF). An 84-year-old woman had a fever and cerebral edema and was initially treated for encephalitis. A review of her magnetic resonance imaging findings revealed abnormal blood flow signals. After cerebral angiography, the patient was finally diagnosed with left transverse-sigmoid sinus dAVF. The present case showed that dAVF can also present with an acute onset and a fever, mimicking acute encephalitis. Because the treatments for encephalitis and dAVF differ greatly, the possibility of dAVF should also be considered when diagnosing encephalitis.

Pilot study of fractal dimension analysis of osteogenesis for bone substitute materials of Bio-Oss in lateral sinus augmentation

BACKGROUND

Fractal dimension (FD) analysis has been proposed and validated in osseointegration-related research. The aim of this study was to evaluate the feasibility of FD analysis in the osteogenesis detection of bone substitute materials (BSMs) of Bio-Oss in maxillary lateral sinus augmentation.

METHODS

Patients who received lateral maxillary sinus augmentation and underwent grafting with BSMs (Bio-Oss) were included in the study. The cross sections of the BSMs under cone-beam computed tomography (CBCT) at mesial, distal, and sagittal directions were obtained immediately after the graft (T0) and 6 months later (T1), and the obtained images were cropped to include only the BSMs. The FD analysis was performed, and the FD value was obtained by the method of box-counting. Paired t-tests and analysis of variance (ANOVA) were used, and p-values <0.05 was considered statistically significant.

RESULTS

Twelve participants with 22 implants, which were inserted simultaneously after sinus augmentation, were included in this study. A total of 22 mesial, 22 distal, and 14 sagittal images were obtained after FD analysis. The mean FD value and standard deviation at T0 was 1.2860 ± 0.0896, while at T1, it was 1.2508±0.1023; thus, significant differences were detected (p = 0.022). However, the increasing or decreasing trend of FD value was not stable, and no significant difference was detected for FD values of mesial, distal, and sagittal images between T0 and T1. ANOVA indicated that no significant difference was detected among the FD values of mesial, distal, and sagittal images at any timepoint. Differences in FD values between the sexes were not significant either.

CONCLUSIONS

Since the FD analysis for the osteogenesis detection of BSMs in maxillary sinus augmentation indicated unstable trends of change, its feasibility is not reliable. The initially rough surface, self-degradation, and volume change of the BSMs during osteogenesis may be the reason for the variation in FD values.

In-out-in technique for petrosal sinus dural arteriovenous fistula obliteration: How I Do It

BACKGROUND

Dural arteriovenous fistulas (dAVFs) at the superior petrosal sinus are a rare but important subtype that pose a high risk of mortality and morbidity. Treatment for these lesions can be challenging with stand-alone endovascular methods.

METHODS

We describe our "in-out-in" technique for disconnecting dAVFs at the superior petrosal sinus, which includes definitive sacrifice of the superior petrosal sinus and the transverse sigmoid sinus, if involved. This method achieves complete fistula obliteration and minimizes recurrence risk with new arterial feeders.

CONCLUSIONS

The in-out-in technique is a safe and effective approach for the treatment of dAVFs involving the superior petrosal sinus.

Endoscopic endonasal access to the lateral recess of the sphenoid sinus

BACKGROUND

The standard endoscopic endonasal approach gives access to the median sphenoid sinus, but not to its lateral part. We propose an endoscopic technique for lesions in the lateral sphenoid sinus.

METHOD

Based on our experience with 28 patients, we have developed a less invasive approach to the lateral recess of the sphenoid sinus, limiting the opening of the maxillary sinus while avoiding resection of the inferior turbinate and ethmoidal cells. The technique is described.

CONCLUSION

The proposed endoscopic approach is reliable and safe to treat CSF leak or tumours located within the lateral recess of the sphenoid sinus.

Survival analysis of implants placed simultaneously with lateral sinus floor elevation in severely atrophic maxilla: A 3- to 12-year retrospective cohort study

OBJECTIVES

To retrospectively evaluate whether implants placed simultaneously with lateral sinus floor elevation (LSFE) in severely atrophic maxilla (residual bone height [RBH] ≤3 mm) could achieve long-term survival and comprehensively analyze the factors influencing their survival rates.

MATERIALS AND METHODS

A total of 123 patients receiving LSFE and simultaneous implant placement from 2010 to 2019 and their 123 implants in sites with RBH ≤3 mm were included in this study. Basic characteristics of patients and implants were collected from the medical record system and cone-beam computed tomography (CBCT) images. Kaplan-Meier survival curves were applied to estimate cumulative survival rates (CSRs) and Cox proportional hazards regression models were used to detect factors influencing implant survival.

RESULTS

The 6-year and 12-year CSR of implants placed in sites with RBH ≤3 mm were 95.7% (95% confidence interval [CI]: 92.1%-99.5%) and 76.6% (95% CI: 58.1%-100%), respectively. Eight patients presented late implant failure. Univariate and multivariate Cox regression analyses demonstrated that RBH ≤2 mm (hazard ratio [HR]: 20.63, p = 0.000) and smoking habit (HR: 6.055, p = 0.024) were significantly associated with long-term implant survival. Specifically, the 10-year CSR of implants in sites with RBH ≤2 mm (53.3%, 95% CI: 27.5%-100%) was dramatically lower than those in sites with RBH >2 mm (92.9%, 95% CI: 81.7%-100%, p = 0.000).

CONCLUSIONS

Implants placed simultaneously with LSFE in sites with RBH ≤3 mm can achieve long-term survival. However, caution is required especially for implantation in sites with RBH ≤2 mm. Besides, the smoking habit is also considered a risk factor jeopardizing long-term implant survival.

Digitally Guided Lateral Sinus Floor Elevation With Simultaneous Implant Placement: 3 Case Reports With Technical Considerations

A sinus floor elevation via lateral window (LSFE) is one of the most widely used bone augmentation procedures for implant therapy in the posterior area of the maxilla. Locating and preparing a correct opening window on the lateral sinus wall is a key step of this procedure. Conventionally, the surgeon designs and locates the window after the flap is reflected based on the information obtained from cone-beam computed tomography (CBCT) images or other diagnostic aids. Nevertheless, in spite of the advancements in CBCT imaging, clinicians may still experience hardships in situating and procuring meticulous access to the maxillary sinus by using CBCT alone. Therefore, in cases requiring an LSFE simultaneous to implant placement, a maxillary sinus surgical guide has been tested and reported to be the amiable method to be utilized as a conjunct to prevent unpredictable consequences according to its application in implying both the direction for the implant and the location of the lateral window. This article presents 3 clinical cases with a fully digital approach to guide the opening of the lateral wall of the maxillary sinus as well as the simultaneous placement of a single implant in an ideal 3D position. Based on the CBCT images and intraoral scan, a surgical guide was fabricated based on 3D software. During surgery, this teeth-supported template can be placed intraorally, guiding sinus window opening preparation. This technique makes the sinus window opening procedure simple and predictable, reduces surgical time and the risk of complications, and allows the placement of the implant in the ideal 3D position.

Six-year extension results of a randomized trial comparing transcrestal and lateral sinus floor elevation at sites with 3-6 mm of residual bone

OBJECTIVES

To comparatively evaluate the 6-year outcomes of transcrestal and lateral sinus floor elevation (tSFE and lSFE, respectively).

METHODS

The 54 patients representing the per-protocol population of a randomized trial comparing implant placement with simultaneous tSFE versus lSFE at sites with a residual bone height of 3-6 mm were invited to participate in the 6-year follow-up visit. Study assessments included: peri-implant marginal bone level at the mesial (mMBL) and distal (dMBL) aspects of the implant, proportion of the entire implant surface in direct contact with the radiopaque area (totCON%), probing depth, bleeding on probing, suppuration on probing, and modified plaque index. Also, the conditions of the peri-implant tissues at 6-year visit were diagnosed according to the case definitions of peri-implant health, mucositis, and peri-implantitis from the 2017 World Workshop.

RESULTS

Forty-three patients (21 treated with tSFE and 22 treated with lSFE) participated in the 6-year visit. Implant survival was 100%. At 6 years, totCON% was 96% (IR: 88%-100%) in tSFE group and 100% (IR: 98%-100%) in lSFE group (p = .036). No significant intergroup difference in patient distribution according to the diagnosis of peri-implant health/disease was observed. Median dMBL was 0.3 mm in tSFE group and 0 mm in lSFE group (p = .024).

CONCLUSIONS

At 6 years following placement concomitantly with tSFE and lSFE, implants showed similar conditions of peri-implant health. Peri-implant bone support was high in both groups and was slightly but significantly lower in tSFE group.

Balloon protection of the vein of Labbé during embolisation of a dural arteriovenous fistula

We describe a novel technique of vein of Labbé preservation using balloon protection during embolisation of a transverse-sigmoid sinus dural arteriovenous fistula. A patient with refractory Cognard type IV fistula of the left transverse-sigmoid sinus and persistent pulsatile tinnitus underwent successful embolisation of the lesion via transarterial route. During embolisation, a dual lumen balloon was simultaneously inflated within the vein of Labbé, at its orifice in the transverse-sigmoid sinus junction, to prevent embolic reflux. This allowed for liquid embolic embolisation of the fistula via the transarterial route resulting in complete occlusion. The patient recovered well with marked improvement of his tinnitus.

Use of a Lateral Sinus Bony Window as an Intraoral Donor Site for Guided Bone Regeneration in Wide Post-Extraction Defects

Maxillary sinus augmentation (MSA) and guided bone regeneration (GBR) have shown successful clinical, radiological, and histological outcomes for implant-related bone reconstruction and have been used to augment bony defects of various shapes and sizes. This study demonstrated that the lateral sinus bony window obtained during MSA can be used as an autogenous block bone graft for the augmentation of wide post-extraction defects. During the uncovering procedure performed 6 months after surgery, the grafted lateral bony window was well integrated with the adjacent native bone, and complete bone filling was observed in all bony defects around the implants. All of the implants survived. Within the limitations of this study, autogenous block bone obtained from lateral window sites can be used as novel donors for the resolution of wide bony defects around implants.

Flow patterns in the venous sinus of pulsatile tinnitus patients with transverse sinus stenosis and underlying vortical flow as a causative factor

BACKGROUND

Transverse sinus stenosis (TSS) is commonly found in Pulsatile Tinnitus (PT) patients. Vortex flow is prominent in venous sinus with stenosis, and so it is important to determine the distribution and strength of the vortical flow to understand its influence on the occurrence of PT.

METHODS

In this study, by using computational fluid dynamics for hemodynamic analysis in patient-specific geometries based on Magnetic Resonance Imaging (MRI), we have investigated the blood flow within the venous sinus of 16 subjects with PT. We have employed both laminar and turbulent flow models for simulations, to obtain (i) streamlines of velocity distribution in the venous sinus, and (ii) pressure distributions of flow patterns in the venous sinus. Then, hemodynamic analysis in the venous sinus recirculation zone was carried out, to determine the flow patterns at the junction of transverse sinuses and sigmoid sinuses. Finally, we have proposed a new model for turbulence evaluation based on the regression analysis of anatomic and hemodynamics parameters.

RESULTS

Correlation analysis between the anatomical parameters and the hemodynamic parameters has shown that stenosis at the transverse sinus was the main factor in the local hemodynamics variation in the venous sinus of patients; in this context, it is shown that vorticity can be used as a prime indicator of the severity of the stenosis function. Our results have shown a significant correlation between the vorticity and the stenotic maximum velocity (SMV) (r = 0.282, p = 0.004). Then, a parameterized prediction model is proposed to determine the vorticity in terms of flow and anatomic variables, termed as the turbulence eddy prediction model (TEP model). Our result have shown that the TEP model is sensitive to the dominant flow distribution, with a high correlation to the flow-based vorticity (r = 0.809, p = 0.009).

CONCLUSIONS

The quantification of the vorticity (as both vorticity and MVV) in the downstream of TSS could be a marker for indication of turbulent energy at the transverse-sigmoid sinus, which could potentially serve as a hemodynamic marker for the functional assessment of the PT-related TSS.

Intracranial computed tomography histogram analysis detects changes in the setting of elevated intracranial pressure and normal imaging

BACKGROUND

Patients with idiopathic intracranial hypertension (IIH) have elevated intracranial pressure (ICP) of unclear etiology. This study evaluated the ability of quantitative intracranial Hounsfield unit (HU) histogram analysis to detect pathophysiological changes from elevated ICP in the setting of a normal head CT.

METHODS

Retrospective analysis of non-contrast-enhanced head CT images of IIH patients and matched controls. Following skull stripping, total intracranial CT voxels within the range of 0-70 HU were divided into seven 10 HU bins. A measurement of total intracranial HU was also calculated for each patient. Imaging studies for IIH patients were reviewed for features of IIH including transverse sinus stenosis (TSS). Histogram measures were compared between IIH and control groups and correlated with imaging and clinical data.

RESULTS

Fourteen IIH patients with CSF opening pressure ≥25 cm water, and 31 age-, sex-, and ethnicity-matched controls were included. Compared to controls, IIH patients had a significantly greater proportion of voxels in the 40-50, 50-60, and 60-70 HU bins (p = 0.003, 0.001, and 0.003, respectively) but similar proportion in the 0-10 HU range. Severity of TSS significantly correlated with total intracranial HU measures. 50-60 HU and 60-70 HU bins demonstrated high AUCs of 0.81 and 0.80, respectively, in differentiating IIH from normal status.

CONCLUSION

Idiopathic intracranial hypertension patients have a greater proportion of high intracranial HU voxels representing blood volume, which may be explained by TSS causing venous congestion. The pattern provides further insights into the pathophysiology of IIH and may be useful for detecting elevated ICP in the setting of normal head CT imaging.

Anatomic Asymmetry of Transverse Sinus May Be Irrelevant to the Prognosis of Intracerebral Hemorrhage

BACKGROUND

We investigate the probable effect of anatomic asymmetry of transverse sinus (TS) on the outcomes of acute intracerebral hemorrhage (ICH), to provide reference for customized treatment.

METHODS

Consecutive patients with imaging-confirmed acute ICH were enrolled from October 2015 through October 2019, and divided into 2 groups: symmetrical and unilateral (left or right) slender TS groups, based on the status of TS in imaging maps. Brain computed tomography (CT) maps of all patients at baseline and half-month post-ICH were obtained, and the volumes of hematoma and the perihematomal edemas (PHE), as well as the modified Rankin Scale (mRS) scores at the month-3 post-ICH between the 2 groups were assessed and analyzed.

RESULTS

A total of 46 eligible patients entered into final analysis, including 18 cases in the slender TS group (14 cases involved the left side while 4 cases involved the right side), and 28 cases in the symmetrical TS group. The mRS scores, hematoma absorption rates, and the residual volumes of PHE of all patients in the 2 groups at half-month post-ICH showed no statistical significance (all P >0.05), and all of the items mentioned above were related to the hematoma volume at baseline (all P <0.001). At the month-3 follow-up post-ICH, the mRS scores between the 2 groups showed no statistical significance as well ( P =0.551).

CONCLUSIONS

Anatomic asymmetry of TS may not affect the prognosis of PHE and clinical outcome after ICH.

Management of Dural Arteriovenous Fistulas

Dural arteriovenous fistula (DAVF) is an acquired lesion. The dural arteries connect with the dural veins within the dura mater in the histopathological study. Sinus type involves the cavernous sinus, transverse-sigmoid sinus, superior sagittal sinus, and anterior condylar confluence (or condylar canal). Non-sinus type involves the anterior cranial base, falcotentorial region, craniocervical junction, convexity, and spinal dura mater.Radical treatment is to obliterate the draining veins in any treatment modalities including endovascular treatment or surgical treatment. Radiosurgery is the last choice. Transvenous embolization plays a main role in the DAVF of the cavernous sinus and anterior condylar confluence. Transarterial embolization with Onyx has dramatically improved the obliteration rate of the transverse-sigmoid, superior sagittal sinuses, and other non-sinus lesions. Transarterial NBCA injection is still the gold standard in the endovascular treatment of the spinal dural and epidural AVFs. Understanding of the functional microvascular anatomy is mandatory, especially in the transarterial liquid injection (Onyx and NBCA). Surgical treatment in the DAVF of the anterior cranial base, craniocervical junction, tentorial region, and spine is a safe and radical treatment. Postoperative follow-up is necessary from the viewpoint of chronological and spacial multi-occurrence of this disease.

Management of idiopathic intracranial hypertension in children utilizing venous sinus stenting

BACKGROUND

Venous sinus stenting (VSS) is an accepted and minimally invasive treatment for adult idiopathic intracranial hypertension (IIH) associated with lateral sinus stenosis (LSS). The efficacy and safety of venous sinus stenting (VSS) in children with IIH has not been established.

METHODS

This is a retrospective analysis of IIH patients 18 years of age or younger with LSS treated with VSS at our institution. Included patients have fulminant disease course or are refractory or intolerant to medical management.

RESULTS

Eight patients were identified; 4 males and 4 females. Mean age is 13.4 years (range 4-18). All patients had severe headaches, 5 had blurred vision, 3 had diplopia and 3 had pulsatile tinnitus. Papilledema was present in 4 patients. Three patients had prior surgical procedures. Four patients were intolerant to medical management, 3 were refractory and 1 had fulminant course. Cerebral venography demonstrated severe stenosis of the dominant sinus in 6 patients and of bilateral co-dominant sinuses in 2 patients. Six patients had intrinsic stenosis and 2 had extrinsic stenosis. Venous sinus stenting (VSS) resulted in improvement of symptoms, papilledema and normalization of CSF opening pressure in 7 patients. No immediate complications were observed. Mean follow-up period is 21 months (range 6-42). Two patients required re-stenting; one responded well and the other had persistent symptoms and underwent subsequent surgical procedures of CSF diversion, suboccipital decompression and duraplasty which were also ineffective.

CONCLUSION

VSS may provide a viable option for pediatric IIH patients who are intolerant to medication, have failed conservative management or prior surgical interventions, or present with fulminant disease.

Association between lateral wall thickness and sinus membrane perforation during lateral sinus elevation: A retrospective study

PURPOSE

This study aimed to investigate the influence of the thickness of the sinus lateral wall on the incidence of sinus membrane perforation.

MATERIALS AND METHODS

A retrospective study was conducted by reviewing dental records of patients who received lateral wall sinus elevation in two educational institutes. The wall thickness 4 mm and 6 mm coronal to the sinus floor was measured with CBCT. The occurrence of sinus membrane perforation was recorded and correlated to the wall thickness using a multilevel regression analysis.

RESULTS

A total of 209 CBCT scans and patient records (N = 251 sinuses, with 42 scans exhibiting bilateral sinuses) were included. The mean residual ridge height was 3.33 ± 1.41 mm. Sinus membrane perforation occurred in 67 sites. The overall mean lateral wall thickness was 1.59 ± 0.84 mm and 1.58 ± 0.83 mm at 4 mm and 6 mm coronal to the sinus floor, respectively. The mean wall thickness at 4 mm and 6 mm coronal to the sinus floor in the perforation group was 2.43 ± 0.56 mm and 2.41 ± 0.56 mm respectively, compared to 1.21 ± 0.40 mm and 1.23 ± 0.41 mm respectively in the non-perforation group (P < 0.01). The perforation rate was 56.4% if the lateral wall thickness at 4 mm coronal to the sinus floor was ≥ 2 mm and 12.1% if it was ≤ 1 mm. A similar difference in perforation rate was reported for the wall thickness measured at 6 mm coronal to the sinus floor (57.9% vs 13.4%). There was no statistically significant difference between smokers and non-smokers regarding perforation rate (P = 0.9604). The presence of sinus septa and sinus wall irregularities did not display a statistically significant difference (P = 0.7155 and P = 0.2971, respectively).

CONCLUSION

The thickness of the lateral wall of the maxillary sinus was related to the occurrence of membrane perforation.

Use of autogenous bone versus deproteinised bovine bone matrix in one-stage lateral sinus floor elevation in severely atrophied maxillae: A 7-year randomised controlled trial

PURPOSE

To compare 100% deproteinised bovine bone matrix grafts (DBBM, test group) and 100% autogenous bone grafts (AB, control group) for lateral maxillary sinus floor elevation in a blinded, parallel-group, randomised clinical trial.

MATERIALS AND METHODS

Patients with 1 to 3 mm of residual bone height were randomised for sinus floor elevation with DBBM or AB grafts and simultaneous implant placement. The outcome variables were implant failure, complications, subjective satisfaction and radiographic peri-implant bone level 7 years after loading.

RESULTS

A total of 20 patients (27 implants) were randomised to the test group and 20 (32 implants) to the control group. Ten patients from the test group and seven from the control group dropped out. Two implant failures occurred in the test group, whereas none were observed in the control group (P = 0.178). One complication occurred in the test group and two were recorded in the control group (P = 1.000). The radiographic peri-implant crestal bone level was 2.5 ± 1.3 mm in the test group and 0.9 ± 0.9 mm in the control group. The difference was 1.6 mm, favouring the control group (95% confidence interval 0.7-2.6; P = 0.002). The difference in vertical bone height was -0.4 mm, favouring the control group (95% confidence interval -1.9-1.1; P = 0.590). The difference in satisfaction measured using a visual analogue scale 7 years after loading was 0.0 mm (95% confidence interval -1.0-0.0; P = 0.639).

CONCLUSIONS

Differences between treatments were found for crestal bone level, favouring the control group. No differences were observed for the other variables evaluated.

Why does unilateral pulsatile tinnitus occur in patients with idiopathic intracranial hypertension?

PURPOSE

To investigate the relevant factors of unilateral pulsatile tinnitus (PT) in patients with idiopathic intracranial hypertension (IIH) using CT.

METHODS

CT angiography images of IIH patients with unilateral PT (n = 19), without PT (n = 13), and controls (n = 32) were reviewed. The characteristics including transverse sinus stenosis (TSS), venous outflow laterality (VOL), sigmoid sinus wall dehiscence (SSWD), and sigmoid sinus diverticulum (SSD) were quantitatively or/and qualitatively detected. VOL was compared between the symptomatic side of IIH patients with PT and the larger side of IIH patients without PT and the controls. TSS, SSWD, and SSD were compared between the symptomatic side of IIH patients with PT, and both sides of the latter two groups.

RESULTS

There was no statistical difference in body mass index or cerebrospinal fluid pressure between IIH patients with and without PT. The prevalence of TSS was significantly higher in IIH patients than that in the controls (p = 0.000), but TSS had no correlation with PT within IIH patients. The prevalence of SSWD successively decreased in IIH patients with PT, without PT, and the controls, with significant differences between each two of three groups (p = 0.000, p' = 0.000, p″ = 0.031). The proportion of VOL and the prevalence of SSD were significantly larger in IIH patients with PT than in the latter groups respectively (p_VOL = 0.005, p'_VOL = 0.000; p_SSD = 0.040, p'_SSD = 0.000). All SSDs in IIH patients with PT were accompanied with SSWD.

CONCLUSION

The dominant VOL and ipsilateral SSWD with/without SSD may be correlated with the occurrence of unilateral PT in IIH patients.

Piezoelectric bone surgery for lateral sinus floor elevation compared with conventional rotary instruments: A systematic review, meta-analysis and trial sequential analysis

AIMS

To evaluate whether piezoelectric bone surgery (PBS) for lateral maxillary sinus floor elevation reduces risk of intraoperative complications, requires prolonged surgical time and improves the survival rate of dental implants in comparison with conventional rotary instruments.

MATERIALS AND METHODS

This meta-analysis followed PRISMA guidelines and was registered in the PROSPERO database (CRD42019122972). The PubMed, Embase, Scopus and Open Grey databases were screened for articles published from 1 January 1990 to 31 December 2018. The selection criteria included randomised controlled trials (RCTs) and case-control studies (CCTs) comparing PBS with rotary instruments in lateral sinus augmentation and reporting intraoperative and postoperative outcomes (e.g. sinus membrane perforations, surgical time and implant failure rate). The risk of bias assessment was performed using the Cochrane Collaboration's tool for RCTs. A meta-analysis was performed, and the power of the meta-analytic findings was assessed via trial sequential analysis (TSA).

RESULTS

Four RCTs met the inclusion criteria and were included in the review. The meta-analysis showed that, although a lower incidence of membrane tearing occurred when using PBS, the difference between the two groups was not significant. However, the power of evidence for this outcome, as determined by the TSA, was weak. Moreover, there was moderate evidence suggesting that PBS prolongs the surgery duration (mean difference of 3.43 minutes), whilst insufficient data was present to assess if PBS improves the survival rate of implants inserted in augmented sinuses.

CONCLUSIONS

The power of the evidence was too weak to confirm the above-mentioned findings and further well-designed randomised clinical trials are needed to draw definitive conclusions.

[Tentorial Dural Arteriovenous Fistula with Bithalamic Lesions and Bilateral Basal Ganglia Hemorrhage:A Case Report]

OBJECTIVE

We report an unusual case of tentorial dural arteriovenous fistula(DAVF)with bithalamic lesions and bilateral intracranial hemorrhage.

CASE PRESENTATION

A 73-year-old man presented with lethargy and progressive cognitive decline. Imaging demonstrated bithalamic edematous lesions and bilateral basal ganglia hemorrhage in the right putamen and left internal capsule. Angiography revealed tentorial DAVF fed by both the internal and external carotid arteries. A shunted pouch was present in the superior petrosal sinus, and retrograde reflux drainage was see in the deep venous system, including the basal vein, vein of Galen, and internal cerebral veins with congestion. Initially, transarterial embolization was palliatively performed, and subsequently, a microsurgery achieved obliteration of the tentorial DAVF. Postoperatively, the bilateral thalamic changes disappeared, although sequela of the intracranial hemorrhage persisted.

CONCLUSION

Deep venous congestion due to tentorial DAVF induced unusual bithalamic lesions and bilateral basal ganglia hemorrhage. Tentorial DAVF was treated with combined endovascular and surgical operations. Tentorial AVF is an aggressive vascular disease, and prompt diagnosis and treatment are necessary.

The Application of Copernic RC Balloon in Endovascular Treatment of Complex Intracranial Dural Arteriovenous Fistula of the Transverse Sigmoid Sinus

BACKGROUND

During endovascular treatment of complex intracranial dural arteriovenous fistulas (DAVFs) of the transverse sigmoid sinus, it can be difficult to preserve the patency of the dural sinus. We have described the details of the transvenous balloon-assisted technique using Copernic RC balloon as a treatment option for patients with complex DAVFs of the transverse sigmoid sinus.

CASE DESCRIPTION

In these 2 cases, the Copernic RC balloon was navigated into the internal jugular vein and placed at the distal end of the DAVFs in the transverse sinus. After the balloon was fully inflated, a transarterial glue embolization or transvenous Onyx tunnel technique was performed, with complete exclusion of the fistula and patency of the transverse sigmoid sinus. No immediate or delayed postoperative complications occurred.

CONCLUSION

Transvenous Copernic RC balloon-assisted embolization of DAVFs in the transverse and sigmoid sinuses is safe and can offer complete occlusion of DAVFs and remission of clinical symptoms.

[Bone regeneration effect of injectable-platelet rich fibrin (I-PRF) in lateral sinus lift: a pilot study]

PURPOSE

The aim of the present research was to evaluate the regeneration effect of injectable-platelet rich fibrin (I-PRF) in lateral sinus lift.

METHODS

A total of 46 cases, who lost their single posterior tooth with residual bone height of 3-5 mm, who needed lateral sinus lift, were treated in our hospital for implantation from June 2014 to Jun 2015. They were randomly divided into 2 groups. In group A, Bio-oss was used as a sole grafting material to fill the sinus; in group B, Bio-oss was used in combination with I-PRF to fill the sinus. Cone-beam CT (CBCT) was taken preoperatively, the residual bone height (RBH) was measured. The new formed bone height (NFBH) was measured immediately, 6 months and 12 months after surgery. ISQ values of implants were taken 4 months, 6 months postoperatively. SPSS 20.0 software was used for statistical analysis.

RESULTS

All cases achieved primary healing, no infection or dehiscence was found. No significant difference of the RBH and NFBH was found between pre-operation or 12 months postoperatively, while significant difference was found immediately and 6 months postoperatively. The value of ISQ in group A was significantly higher than that in group B at 4 months(P＜0.05), and there was no significant difference between 2 groups 6 months after operation(P＞0.05).

CONCLUSIONS

I-PRF is a safe and reliable material in sinus lift, which can effectively shorten the healing time and enhance the effect of osteogenesis.

[Dural Arteriovenous Fistula with Acute Visual Loss Manifestation:A Case Report]

In this report, we are describing a rare case of dural arteriovenous fistula(DAVF)followed by an isolated symptom of bilateral visual acuity disturbance. The patient was a 67-year-old man suffering from progressive bilateral visual acuity disturbance. Angiography revealed a diffuse arteriovenous fistula in the left transverse-sigmoid sinus affected by severe venous congestion. Visual acuity disturbance is likely to have been caused by increased intracranial pressure(IICP). Venous congestion as well as visual acuity were gradually improved following three transarterial embolizations. It is possible that a gradual progression of the clinical condition has caused only visual acuity disturbance without any other IICP symptoms, which is similar to pseudotumor cerebri. Should an unexplained visual acuity loss occur, the case should be investigated by considering DAVF.

A modification of endoscopic endonasal approach for management of encephaloceles in sphenoid sinus lateral recess

Spontaneous cerebrospinal fluid leak with meningoencephaloceles in sphenoid sinus lateral recess is challenging. Transnasal visualization of this area is difficult, especially when large pneumatization is present. External approaches to this region involve aggressive surgery and are often associated with significant morbidity. The aim of this study is to assess the real effectiveness of a modification of the endoscopic endonasal approach for their management. This is a prospective case series study and was conducted at Otolaryngology department, Ain Shams University Hospitals, Cairo, Egypt. Seven patients with spontaneous cerebrospinal fluid leak with meningoencephaloceles in the sphenoid sinus lateral recess were included. Diagnosis was confirmed by: analysis for beta-2 transferrin and imaging. They were managed with endoscopic endonasal retrograde trans-sphenoid approach described in this study with multilayered reconstruction of the defect. Mean age of our patients was 40.14 ± 8.35 years; mean BMI was 36.37 ± 2.59 kg/m². Primary empty sella was present and osteodural defect was identified in superior wall of sphenoid sinus lateral recess with punched out and regular smooth edges. Mean intra-cranial pressure was (26.42 ± 3.87 mmH₂O) and size of defect was less than 10 mm, mean 7.85 ± 1.34. Mean-operative time was 169.28 ± 21.87 min. The mean hospital stay was 7.42 ± 1.39 days. No cerebrospinal fluid leak recurrences were observed during follow-up period that ranged from 37 to 48 months. Endoscopic endonasal retrograde trans-sphenoid approach provides a wide, safe, and direct route to the management of sphenoid sinus lateral recess cerebrospinal fluid leak.

[A case of transverse-sigmoid sinus dural arteriovenous fistula that became symptomatic after removal of coexisting sphenoid ridge meningioma]

Here, we describe a case with a transverse-sigmoid sinus(TSS)dural arteriovenous fistula(DAVF)with sinus occlusion at its proximal and distal ends;the TSS DAVF turned symptomatic after removal of a coexisting symptomatic sphenoid ridge meningioma. The patient was a 70-year-old man presenting with decreased daily activities and mentation due to dysphasia. Magnetic resonance imaging revealed a large, left sphenoid ridge meningioma. Angiography revealed a tumor stain and a coexisting left TSS DAVF with sinus occlusion at its proximal and distal ends. Cortical venous reflux(CVR)into the temporal veins was observed. After successful tumor removal, the superficial middle cerebral vein was arterialized intraoperatively. However, the patient showed worsened consciousness and dysphasia after the operation. Repeated angiography revealed CVR into the superficial middle cerebral vein through a sphenopetrosal sinus. Transvenous embolization was performed via the contralateral inferior petrosal and intercavernous sinus, which allowed access to the ipsilateral superior petrosal sinus(SPS);the procedure successfully eliminated CVR, while preserving the SPS. The patient demonstrated full recovery. This case exemplifies a coexisting TSS DAVF after tumor resection, and superficial middle cerebral vein decompression due to the sphenopetrosal sinus, an alternate drainage pathway for the superficial middle cerebral vein.

Managing ocean information in the digital era--events in Canada open questions about the role of marine science libraries

Information is the foundation of evidence-based policies for effective marine environmental protection and conservation. In Canada, the cutback of marine science libraries introduces key questions about the role of such institutions and the management of ocean information in the digital age. How vital are such libraries in the mission of studying and protecting the oceans? What is the fate and value of the massive grey literature holdings, including archival materials, much of which is not in digital form but which often contains vital data? How important is this literature generally in the marine environmental sciences? Are we likely to forget the history of the marine pollution field if our digital focus eclipses the need for and access to comprehensive collections and skilled information specialists? This paper explores these and other questions against the backdrop of unprecedented changes in the federal libraries, marine environmental science and legislation in Canada.

Unilateral transverse sinus stenting of patients with idiopathic intracranial hypertension

BACKGROUND AND PURPOSE

The pathophysiology of IIH remains unknown. TS stenoses have been observed in a high proportion of these patients. Stent placement to remove this potential obstruction to venous outflow has been proposed as a treatment option for patients with IIH refractory to medical treatment.

MATERIALS AND METHODS

The clinical presentation, treatment, and outcome of patients with refractory IIH evaluated for venous sinus stent placement at a tertiary care center was retrospectively reviewed.

RESULTS

Thirteen female patients with IIH were evaluated for sinovenous stent placement. Moderate sinus stenoses with normal intrasinus pressures were found in 3 patients and therefore stent placement was not performed. Ten patients had elevated intrasinus pressures (pressure gradient across stenosis, 11-50 mm Hg), which decreased following unilateral TS stent placement. Headaches improved or resolved in all stented patients. Papilledema resolved completely or almost completely in 8 patients and significantly improved in 2 patients. One patient developed optic atrophy. There were no major periprocedural complications.

CONCLUSIONS

In this small case series, restoring the patency of stenotic venous sinuses with a stent in patients with refractory IIH resulted in symptomatic improvement in all treated patients. The safety and efficacy of this procedure should be evaluated in a randomized controlled study to determine its role within the armamentarium of therapeutic options for patients with IIH.

[Endovascular treatment for dural arteriovenous fistula]

Intracranial dural arteriovenous fistulas (DAVFs) are acquired abnormal epidural arteriovenous shunts, particularly at the sinus wall. Most of the DAVFs are associated with progressive sinus occlusion. They are located in the cavernous sinus, lateral (transverse-sigmoid) sinus, superior-sagittal sinus, anterior condylar confluence, tentorial sinus, craniocervical junction, and anterior skull base (ethmoidal sinus). The treatment strategy differs based on the etiology and drainage pattern of DAVFs. The most effective treatment for DAVFs at the sinus wall is transvenous embolization (TVE) with coils. The target coil packing is effective if the sinus point is identified. Certain cases that are difficult to approach transvenously are treated with transarterial embolization (TAE) by using liquid materials like such glue. In particular cases with sinus occlusive lesion sinus reconstruction with sinoplasty is effective. The cases with failed or impossible endovascular approach should be treated with surgical interruption of shunts or by radiosurgery. The most frequent complication of TAE is brain and nerve ischemia due to the overembolization or migration, and that in TVE is the bleeding due to obstruction of the drainage route and nerve compression due to overpacking of coils.

[Radiosurgery for intracranial dural arteriovenous fistulas--indications for limitations for gamma knife treatment]

We summarize the results of gamma knife treatment for dural arterivenous fistula (DAVF), are report our study. Since the early 1990s, DAVFs have been treated in the same manner as arteriovenous malformations (AVMs), i.e., by radiosurgery, performed with or without embolization. DAVFs in the cavernous sinus, transverse-sigmoid sinus, and cerebellar tent were treated with a marginal dose of 18 to 20 Gy. The current obliteration rates of DAVF reported in literature are not low when compared with those of AVM. Excellent DAVF obliteration rates were observed in our study, which were similar to those reported in the literature. In fact, complete response (CR) was observed in 9 cases, partial response (PR) in 9 cases, and partical obliteration in 6 cases during the mean follow-up of 27 months. Moreover, considerable neurological improvements were noted, which apparently began at an early stage post radiosurgery. Bleeding was observed 2 cases associated with cortical reflux during the follow-up. In conclusion, radiosurgery for DAVF is very useful for both the obliteration of the fistula and for the improvement of clinical signs. However, prior to performing radiosurgery, the lesions with cortical reflux should be interrupted by initially treated with surgery or embolization.