Association of Extent of Transverse Sinus Stenosis With Cerebral Glymphatic Clearance in Patients With Idiopathic Intracranial Hypertension.

BACKGROUND AND OBJECTIVES: Idiopathic intracranial hypertension (IIH) is a neurologic disorder characterized by symptoms of elevated intracranial pressure in the absence of a clear cause. There is a developing theory that IIH may, in part, be related to abnormal cerebral glymphatic clearance. In addition, transverse sinus stenosis (TSS) is a common finding in IIH of unclear pathophysiologic significance. Similarly, whether or not TSS is associated with glymphatic outflow in IIH is unknown. The aim of this investigation was to explore the possible association between glymphatic outflow and extent of TSS in patients with IIH. METHODS: The study cohort consisted of patients with IIH and healthy controls who were retrospectively identified from our tertiary care institution located in upstate New York from 2016 to 2023. Patients with IIH were included if they had brain MRIs completed with sufficient sequences for analysis. Brain MRIs were computationally analyzed using diffusion tensor imaging analysis along the perivascular space technique to quantify the glymphatic function in patients with IIH. Glymphatic clearance, the primary outcome, was then correlated with the degree of TSS on MR venography using 2 different scoring systems, the 'Farb score' and 'Carvalho score.' RESULTS: Overall, 81 patients with IIH (70 [86%] female, mean age 29.8 years [SD: 8.2 years], mean BMI 41 [SD: 8.4]) and 10 normal controls were identified with sufficient imaging. Based on the Carvalho TSS score, IIH patients without TSS had significantly lower glymphatic clearance than healthy controls (mean ALPS index: 1.196 [SD: 0.05] vs 1.238 [SD: 0.04], respectively; p = 0.018). Furthermore, IIH patients with TSS had significantly lower glymphatic outflow than healthy controls (1.129 [SD: 0.07] vs 1.238 [SD: 0.04], respectively; p < 0.0001) and IIH patients without TSS (1.129 [SD: 0.07] vs 1.196 [SD: 0.05], respectively; p < 0.0001). In addition, there was a significant association between increasing extent of TSS and declining glymphatic clearance (p < 0.0001, R = 0.62). Finally, IIH patients with severe TSS had significantly lower glymphatic flow than IIH patients with mild stenosis (1.121 [SD: 0.07] vs 1.178 [SD: 0.05], respectively; p < 0.0001). These findings were similarly recapitulated using the Farb TSS scoring system. DISCUSSION: These preliminary findings suggest that the extent of TSS is associated with the degree of glymphatic clearance in IIH, providing novel insights into IIH pathophysiology. Further research is required to clarify the possible causal relationship between TSS and impaired glymphatic clearance in IIH.

[Transverse Sinus / Sigmoid Sinus].

The transverse sinus(TS)and sigmoid sinus(SS)are common sites for dural arteriovenous fistulas, and an understanding of vascular anatomy is important when developing treatment strategies. In recent years, transarterial embolization, with a liquid embolization material, has become the treatment of choice, preserving the sinus without extensive coil filling of the affected sinus. With this expansion of therapeutic options, we feel that an understanding of the microanatomy has become more important. For example, the exact site where the vein of Labbé joins the TS should be determined. This article focuses on the development and anatomy of the TS and SS and makes points that should be considered when treating dural arteriovenous fistulas.

Safety evaluation of sinus patency after stereotactic radiosurgery for transverse-sigmoid sinus dural arteriovenous fistulas: implications of treatment options for patients with Borden type I fistulas.

OBJECTIVE: This study aimed to assess the efficacy and safety of stereotactic radiosurgery (SRS) in treating transverse-sigmoid sinus dural arteriovenous fistulas (TSS DAVFs), and to investigate post-SRS sinus patency, focusing on the risk factors associated with treated sinus occlusion. METHODS: Data from 34 patients treated with SRS between January 2006 and April 2023 were analyzed. Detailed angioarchitecture was confirmed using digital subtraction angiography before SRS. Angiography of the ipsilateral internal carotid artery and vertebral artery was performed to evaluate whether the involved side of the TSS was used for normal venous drainage. TSS stenosis was defined as sinus diameter < 50% of the normal proximal diameter. DAVF shunt obliteration, TSS occlusion, neurological status, and adverse events were also evaluated. RESULTS: Of the 34 patients, 21 had Borden type I and 14 had Borden type II DAVFs. The median age at SRS was 64 years (interquartile range 54-71 years), and the follow-up period was 31 months (interquartile range 15-94 months). Complete shunt obliteration was achieved in 24 (70.6%) patients. The cumulative 2-, 3-, and 5-year shunt obliteration rates were 49.6%, 71.2%, and 86.0%, respectively. Borden type I had higher obliteration rates (60.5%, 83.1%, and 94.4%, respectively) than Borden type II (41.7%, 51.4%, and 75.7%, respectively; p = 0.034). TSS occlusion occurred in 5 patients (14.7%). The cumulative 1-, 5-, and 10-year TSS occlusion rates were 2.9%, 8.3%, and 23.6%, respectively, across the entire cohort. All occlusions occurred exclusively in the sinuses that were not used for normal venous drainage. Cox proportional analyses revealed that TSS stenosis and the sinus not being used for normal venous drainage were significantly associated with a greater risk of TSS occlusion after SRS (HR 9.44, 95% CI 1.01-77.13; p = 0.049). CONCLUSIONS: SRS is effective and safe for TSS DAVF and results in favorable shunt obliteration, symptom improvement, and low complication rates. TSS occlusion after SRS is asymptomatic and is limited to sinuses that are not used for normal venous drainage.

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.

Occipital emissary vein existence and its impact on the diagnosis of idiopathic intracranial hypertension in pediatric patients.

PURPOSE: This study aimed to investigate the efficacy of occipital emissary vein (OEV) detection in the diagnosis of idiopathic intracranial hypertension (IHH) in the pediatric age group, and to compare the prevalence and luminal diameter of OEV in patients with IHH and in healthy control subjects. METHODS: Conventional magnetic resonance imaging findings were assessed in the patients with IHH and in healthy control subjects who were under the age of 18, by two observers. The presence and luminal dimension of OEV and transverse sinus stenosis were also evaluated and compared between these two groups with magnetic resonance venography techniques. RESULTS: The rate of OEV existence was 7 times higher in the IIH group compared to the control group based on the second observer outcome (p = 0.010, OR = 7.0), with a very good interobserver agreement (Ƙ = 0.85). The dimension of OEV ranged between 0.6 and 2.5 mm. There was no correlation found between the opening pressure and the dimension of OEV (p = 0.834). CONCLUSION: In conclusion, OEV existence could be an additional radiological finding for diagnosing IHH among pediatric patients, alongside other conventional findings.

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.

Mini Crestal Sinus Lift With Bone Grafting and Simultaneous Insertion of Implants in Severe Maxillary Conditions as an Alternative to Lateral Sinus Lift: Multicase Study Report of Different Techniques.

The present study evaluates the efficacy and clinical outcomes of crestal sinus lift techniques used to elevate the sinus floor simultaneously with bone grafting and implant placement as a possible and reproducible alternative to lateral sinus lift. Patients underwent different crestal sinus elevation techniques. The heterologous biomaterial was used as graft material, and multiple implants were placed simultaneously after sinus augmentation. Radiographic and clinical examinations were performed during follow-up. All procedures were successfully performed without any apparent perforation of the Schneider membrane. The sinus floor was augmented with an average height of 5 mm (range: 2.8-7.4 mm). The implants healed smoothly with healing screws. Peri-implant marginal bone was stable with a mean follow-up of 50 months (range: 33-71 mo). No complications were observed during the follow-up. Based on the limited data collected in this study, the new crestal sinus elevation approach can effectively raise the sinus floor and reduce the incidence of postoperative complications. Other cases with long-term follow-up are needed to confirm and improve this crestal sinus lift technique.

Effectiveness, Morbidity, and Costs of Transcrestal and Lateral Sinus Floor Elevation at Sites with Different Residual Bone Heights: A Re-Analysis of Data from a Parallel-Arm Randomized Trial.

PURPOSE: To comparatively evaluate transcrestal sinus floor elevation (tSFE) and lateral sinus floor elevation (lSFE) at sites with different residual bone heights (RBHs). MATERIALS AND METHODS: A re-analysis of data from a parallel-arm, randomized trial comparatively evaluating tSFE and lSFE was performed. Within each RBH interval (< 4 mm or ≥ 4 mm), tSFE and lSFE groups were compared for chair time, surgery-related costs, morbidity, and radiographic parameters (including the proportion of the implant surface in direct contact with the radiopaque area [totCON%]). RESULTS: The intention-to-treat (ITT) population consisted of 29 and 28 patients in the tSFE and lSFE groups, respectively. Irrespective of RBH, both tSFE and lSFE lead to a median totCON% of 100%. At sites with RBH < 4 mm, pain severity was significantly higher at days 0 and 1 in the tSFE group, with no intergroup difference in the dose of analgesics. LSFE was associated with a significantly higher frequency of bruising and greater cost. At sites with RBH ≥ 4 mm, a significantly lower frequency of postoperative signs/symptoms, less chair time, and lower costs were observed in the tSFE group. CONCLUSIONS: The selection of tSFE or lSFE within the investigated RBH intervals seems to be supported by differences in chair time, costs, and morbidity between the two techniques. At sites with RBH < 4 mm, clinicians preferring tSFE should encourage the administration of analgesics according to a predefined plan in the early postoperative phase. At sites with RBH ≥ 4 mm, tSFE should be preferred to lSFE due to reduced chair time, costs, and morbidity.

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.

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.

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.

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.

Absence of the torcular, review of venous sinus anatomy, and the simplified dural sinus classification.

BACKGROUND: Classically, the torcular Herophili is described as the symmetric junction between the superior sagittal sinus (SSS), transverse sinuses (TSs), and straight sinus (SS). However, finding this pattern in practice is not standard. Anatomical variations are common, and different drainage patterns should be expected. Existing literature proposes highly detailed descriptions and classifications of this region. Still, a simplified and practical categorization is not available. METHODS: We present an anatomical finding of the torcular Herophili discovered on a cadaveric dissection. Then, we conducted a retrospective study examining the 100 most recent cranial magnetic resonance venographies (MRVs) from the Mayo Clinic, labeling them with a new proposed dural sinus classification system. Images were initially classified by two authors and further validated by a board-certified neurosurgeon and a board-certified neuroradiologist from our institution. To measure consistency in image identification, two additional international neurosurgeons were asked to classify a subset of the same MRV images, and their answers were compared. RESULTS: Of the MRV cohort, 33 patients were male and 67 were female. Their ages ranged from 18 to 86 years, with a mean of 47.35 years and a median of 49 years. Upon examination, 53 patients presented as confluent (53%), 9 as SSS divergent (9%), 25 as SS divergent (25%), 11 as circular (11%), and 2 as trifurcated (2%). The inter-rater reliability ranked very good; agreement between the two neurosurgeons was 83% (κ = 0.830, p < 0.0005). CONCLUSION: The confluence of the venous sinuses is a highly variable anatomical area that is rarely evaluated with neuroimaging before surgery. The classic textbook configuration is not the rule. Using a simplified classification system may increase awareness and hopefully patient safety by preparing the physician for anatomical variations that they will encounter in a surgical or clinical scenario.

Is one-stage lateral sinus lift and implantation safe in severely atrophic maxillae? Results of a comparative pilot study.

PURPOSE: The aim of this retrospective comparative study was to evaluate the survival of dental implants placed in the posterior maxilla with a residual bone height less than 3 mm using a one-stage lateral sinus lifting approach. The research question was whether in very severely atrophied maxillary bones (residual height < 3 mm), a sinus lift with simultaneous implant placement would be associated with a higher complication rate compared to single-stage sinus lifts at average residual alveolar process heights. METHODS: Complications of 63 implants, where the residual bone height was below 3 mm, were compared to a reference group of 40 implants, which were inserted using a one-stage lateral sinus lift in maxillae with at least 3 mm residual bone height. Implant survival, bleeding-on-probing, the presence of peri-implant mucositis and the occurrence of peri-implantitis were documented. RESULTS: The mean follow-up time for implant survival was 80.3 ± 25.9 months. One implant out of 63 was lost in the severely atrophic maxilla group and two implants out of 40 were lost in the reference group. There were no differences in the occurrence of implant loss (p = 0.558), bleeding-on-probing (p = 0.087), peri-implantitis (p = 0.999) and peri-implant mucositis (p = 0.797) between the severely atrophic alveolar ridge group and the reference group. CONCLUSIONS: Even in severely atrophic maxillae with < 3 mm residual bone height, a one-stage maxillary sinus lift and immediate implant placement can be carried out safely.

Effects of different grafting materials on volumetric changes in the Schneiderian membrane following lateral maxillary sinus floor elevation: a preliminary study.

OBJECTIVES: To investigate the potential influence of different grafting materials on maxillary sinus membrane dimensions and ostium patency following lateral sinus floor elevation (SFE) as assessed using cone-beam computed tomography (CBCT). MATERIALS AND METHODS: A total of 40 sinuses in 40 patients were included. Twenty sinuses were referred for SFE with deproteinized bovine bone mineral (DBBM), and the remaining 20 sinuses were grafted with calcium phosphate (CP). CBCT was performed prior to and 3 to 4 days after surgery. The dimensions of the Schneiderian membrane volume and ostium patency were evaluated, and potential relationships between volumetric changes and any associated factors were analyzed. RESULTS: The median increase in membrane-whole cavity volume ratios was 43.97% in the DBBM group and 67.58% in the CP group, demonstrating no statistically significant difference (p = 0.17). The rates of increased obstruction after SFE were 11.1% for the DBBM group versus 44.4% for the CP group (p = 0.03). The graft volume was found to be positively correlated with the postoperative membrane-whole cavity volume ratio (r = 0.79; p < 0.01) and the membrane-whole cavity volume ratio increase (r = 0.71; p < 0.01). CONCLUSIONS: The two grafting materials seem to have a similar effect on transient volumetric changes in the sinus mucosa. However, the choice of grafting material should still be made with caution since sinuses grafted using DBBM exhibited less swelling and less ostium obstruction.

Infantile dural sinus malformation: curative embolization in two stages with the Scepter mini balloon microcatheter.

Endovascular embolization is the mainstay for treatment of infantile dural sinus malformations.1 2 Distal access and flow control are limiting factors in controlled embolization.3-6 The Scepter mini catheter (Microvention, Aliso Viejo, California, USA) is a low-profile, dual-lumen balloon microcatheter designed to provide navigability in small-caliber, tortuous intracranial vessels. In this technical video, we demonstrate the staged embolization of a dural sinus malformation with multiple arteriovenous fistulae using the Scepter mini catheter (video 1). In the newborn patient, embolizations were performed through the parietal branches of the left and right middle meningeal arteries. The catheter easily navigated into the small feeding arteries. No neurological complications occurred due to the procedures. Post-embolization injections demonstrated significant flow reduction into the malformation. Three-month follow-up angiography illustrated resolution of the previously dilated left transverse sinus. Complete obliteration of the dural sinus malformation was achieved in the newborn patient. neurintsurg;15/1/97/V1F1V1Video 1Curative embolization in two stages with the Scepter mini balloon microcatheter. ΑP, anteroposterior; CCA, common carotid artery.

Radiographic outcomes of lateral sinus floor elevation with and without bone window repositioning: one-year results of a randomized controlled trial.

The objective of this study was to perform a comparative evaluation of the radiographic outcomes of lateral sinus floor elevation with and without bone window repositioning (BLSFE and LSFE, respectively) when applied concomitantly with implant placement. A randomized controlled clinical trial was conducted between February 1, 2016 and May 1, 2017 including 26 individuals with at least one missing tooth. Participants were randomized 1:1 to undergo BLSFE (10 participants, 16 implants) or LSFE (13 participants, 19 implants). Bovine-derived xenograft was used in both groups and the implants were inserted concomitantly. In the BLSFE group, the antrostomy was covered with a repositioned bone window and then with a concentrated growth factors (CGF) membrane. In the LSFE group, the antrostomy was covered with a CGF membrane. Panoramic radiographs were taken before surgery (T0), immediately postoperative (T1), and at 12 months postoperative (6 months after loading) (T2). Marginal bone loss (MBL), apical bone gain, augmented alveolar bone height, and intra-sinus bone augmentation were evaluated on panoramic radiographs at T2. A linear regression analysis with generalized estimating equation models was performed. The implant survival rate was 100% at 1 year after implant surgery. The residual alveolar bone height at T0 was comparable in the BLSFE and LSFE groups (3.58 ± 1.49 mm vs 4.12 ± 1.61, P = 0.32), as was the alveolar bone height at T1 (13.61 ± 1.82 mm vs 12.38 ± 1.82 mm, P = 0.06). At T2, significantly higher alveolar bone height, intra-sinus bone augmentation, and apical bone gain, and lower distal MBL were observed in the BLSFE group when compared to the LSFE group, with adjusting for covariates (ß = 2.44, 95% CI 1.42-3.46, P < 0.0001; ß = 2.38, 95% CI 1.35-3.41, P < 0.0001; ß = 2.33, 95% CI 1.23-3.42, P < 0.0001; and ß = -0.43, 95% CI -0.83 to -0.02, P = 0.038, respectively). No significant difference was observed for mesial MBL or apical bone resorption at T2. Lateral sinus floor elevation with bone window repositioning may result in higher bone augmentation after 1 year than the traditional approach. Further research is needed to elucidate the effect of lateral sinus floor elevation with bone window repositioning.

Safe Region of Craniotomy to Access the Cerebellopontine Region by Retrosigmoid Approach: A Radiological and Anatomical Study.

Accurately positioning the sigmoid sinus (SS), transverse sinus (TS), and vertebral artery (VA) is significantly important during the retrosigmoid (RS) approach. This study aimed to use emissary vein and digastric point as landmarks in high-resolution computer topographic image to locate the SS, TS, and VA to help surgeons to avoid injuring these vascular structures during RS craniotomy. Computed topographic (CT) angiography images of 107 individuals were included, the measurement was performed on coronal, sagittal, and axis planes after the multiplanar reformation. Distance from the emissary vein and digastric point to the posterior boundary of the SS, inferior boundary of the TS were measured by CT angiography preoperatively and in the skull intraoperatively. The VA was also located by emissary vein and digastric point. No significant difference was identified between the distances measured in the CT and skull. Our findings provide anatomical information for locating the boundary of the SS, TS, and V3-VA based on the fixed bony landmarks. Verified by skull measurement, high-resolution CT scan is a cost-effective and reliable tool for identifying the location of the arteries and sinus, which could be widely used to guarantee the safety of RS approach craniectomy.

Sacrifice or preserve the superior petrosal vein in microvascular decompression surgery: a systematic review and meta-analysis.

OBJECTIVE: In microvascular decompression (MVD) surgery through the retrosigmoid approach, the surgeon may have to sacrifice the superior petrosal vein (SPV). However, this is a controversial maneuver. To date, high-level evidence comparing the operative outcomes of patients who underwent MVD with and without SPV sacrifice is lacking. Therefore, this study sought to bridge this gap. METHODS: The authors searched the Medline and PubMed databases with appropriate Medical Subject Heading (MeSH) terms and keywords. The primary outcome was vascular-related complications; secondary outcomes were new neurological deficit, cerebrospinal fluid (CSF) leak, and neuralgia relief. The pooled proportions of outcomes and OR (95% CI) for categorical data were calculated by using the logit transformation and Mantel-Haenszel methods, respectively. RESULTS: Six studies yielding 1143 patients were included, of which 618 patients had their SPV sacrificed. The pooled proportion (95% CI) values were 3.82 (0.87-15.17) for vascular-related complications, 3.64 (1.0-12.42) for new neurological deficits, 2.85 (1.21-6.58) for CSF leaks, and 88.90 (84.90-91.94) for neuralgia relief. The meta-analysis concluded that, whether the surgeon sacrificed or preserved the SPV, the odds were similar for vascular-related complications (2.5% vs 1.5%, OR [95% CI] 1.01 [0.33-3.09], p = 0.99), new neurological deficits (1.2% vs 2.8%, OR [95% CI] 0.55 [0.18-1.66], p = 0.29), CSF leak (3.1% vs 2.1%, OR [95% CI] 1.16 [0.46-2.94], p = 0.75), and neuralgia relief (86.6% vs 87%, OR [95% CI] 0.96 [0.62-1.49], p = 0.84). CONCLUSIONS: SPV sacrifice is as safe as SPV preservation. The authors recommend intentional SPV sacrifice when gentle retraction fails to enhance surgical field visualization and if the surgeon encounters SPV-related neurovascular conflict and/or anticipates impeding SPV-related bleeding.