Occipital Sinus-Sparing Linear Paramedian Dural Incision: A Technical Note and Case Series for Median Suboccipital Approach

BACKGROUND

Durotomies, traditionally used during the midline suboccipital approach, involve sacrificing the occipital sinus (OS) with consequent shrinking of the dura, risk of venous complications, difficulty performing watertight closure, and a higher rate of postoperative cerebrospinal fluid (CSF) leaks. The present technical note describes the OS-sparing linear paramedian dural incision, which leads to a decrease in the risk of complications during the median suboccipital approach in our case series.

METHODS

The OS-sparing linear incision technique involves a dural incision placed 1 cm lateral to the OS. The angle of view of the microscope is frequently changed to overcome the narrowed exposure of the linear durotomy. Copious irrigation with saline prevents drying of the dura. A running watertight closure of the dura is performed. The overall results of 5 cases are reviewed.

RESULTS

The cases were 3 tumors and 2 cavernomas. The OS was preserved in all 5, and no duraplasty was needed. The average dura closure time was 16.8 minutes. No CSF leak occurred, and no wound complications were observed. A gross total resection of the lesion was achieved in all the patients. The mean follow-up was 10.2 months, and there were no late complications related to the dura closure.

CONCLUSIONS

In comparison to the types of durotomies conventionally used for the midline suboccipital approach, the OS-sparing linear paramedian dural incision entails lower risks of bleeding, venous complications, CSF leaks, and infections by avoiding duraplasty. Validation of this technical note on a larger patient cohort is needed.

Transorbital neuroendoscopic surgery for treatment of sphenoid wing meningiomas extending to the cavernous sinus: clinical implications and a technical illustration

OBJECTIVE

The aim of this study was to evaluate the efficacy and safety of transorbital neuroendoscopic surgery (TONES) in the management of sphenoid wing meningiomas (SWMs) with cavernous sinus and orbital invasion.

METHODS

The authors conducted a retrospective review of 32 patients with SWMs treated at Gazi University using TONES from October 2019 to May 2023. The study includes clinical applications to elucidate the endoscopic transorbital approach. Surgical techniques focused on safe subtotal resection, aiming to minimize residual tumor volume for subsequent radiosurgery. Data were collected on patient demographics, tumor characteristics, surgical procedures, complications, and postoperative outcomes, including radiological imaging and ophthalmological evaluations.

RESULTS

Surgical dissections delineated a three-phase endoscopic transorbital approach: extraorbital, intraorbital, and intracranial. In the clinical application, gross-total resection was not achieved in any patient because of planned postoperative Gamma Knife radiosurgery. The mean follow-up period was 16.3 months. Of 30 patients with preoperative proptosis, 25 experienced postoperative improvement. No new-onset extraocular muscle paresis or visual loss occurred postoperatively. The average hospital stay was 1.15 days, with minimal complications and no significant morbidity or mortality.

CONCLUSIONS

Total resection of SWMs invading the cavernous sinus and orbit is associated with substantial risks, particularly cranial nerve deficits. TONES offers a minimally invasive alternative, reducing morbidity compared with transcranial approaches, and represents a significant advancement in the surgical management of SWMs, especially those extending into the cavernous sinus and orbit. The approach provides a safe, effective, and patient-centric approach, prioritizing subtotal resection to minimize neurological deficits while preparing patients for adjunctive radiosurgery. This study positions TONES as a transformative surgical technique, aligning therapeutic efficacy with neurovascular preservation and postoperative recovery.

Endoscopic Endonasal Approach to the Orbit: A Case Series and Clinical Experience Emphasizing the Advantages of the Ipsilateral Mononostril Technique

BACKGROUND

Lesions situated within the orbit pose significant challenges in management due to the confined space they occupy and their proximity to critical anatomical structures. The objective of our study is to assess the feasibility of the ipsilateral endoscopic endonasal approach for orbital cavernous hemangiomas and to comprehend the surgical anatomy of the orbital apex and inferomedial orbital structures.

METHODS

Thirteen patients (8 women, 5 men), with ages ranging from 25 to 54 years (mean 35.2 ± 8.3 years), with orbital cavernous hemangioma who underwent surgery via the ipsilateral mononostril endoscopic endonasal approach between August 2018 and August 2023 were retrospectively evaluated. Demographic characteristics, clinical data, radiographic images, and clinical outcomes of the patients were collected from digital medical records.

RESULTS

The left orbit was more commonly affected (9 left, 4 right). The average postoperative follow-up duration was 22.2 months (range: 6-50 months). Among the 13 cases of orbital cavernous hemangioma, 1 (7.7%) was located in the extraconal compartment, and 12 (92.3%) were situated in the intraconal compartment. Complete surgical resection of the tumor was successfully achieved in all patients.

CONCLUSIONS

Our study highlights the potential advantages of employing a purely ipsilateral mononostril endoscopic endonasal approach for orbital surgery, particularly for accessing the orbital apex and managing medial and inferomedial orbital lesions. This technique holds promise for reducing morbidity and enhancing outcomes, especially when combined with careful patient selection, preoperative planning, and advanced endoscopic skills.

Creation of a microsurgical neuroanatomy laboratory and virtual operating room: a preliminary study

OBJECTIVE

A comprehensive understanding of microsurgical neuroanatomy, familiarity with the operating room environment, patient positioning in relation to the surgery, and knowledge of surgical approaches is crucial in neurosurgical education. However, challenges such as limited patient exposure, heightened patient safety concerns, a decreased availability of surgical cases during training, and difficulties in accessing cadavers and laboratories have adversely impacted this education. Three-dimensional (3D) models and augmented reality (AR) applications can be utilized to depict the cortical and white matter anatomy of the brain, create virtual models of patient surgical positions, and simulate the operating room and neuroanatomy laboratory environment. Herein, the authors, who used a single application, aimed to demonstrate the creation of 3D models of anatomical cadaver dissections, surgical approaches, patient surgical positions, and operating room and laboratory designs as alternative educational materials for neurosurgical training.

METHODS

A 3D modeling application (Scaniverse) was employed to generate 3D models of cadaveric brain specimens and surgical approaches using photogrammetry. It was also used to create virtual representations of the operating room and laboratory environment, as well as the surgical positions of patients, by utilizing light detection and ranging (LiDAR) sensor technology for accurate spatial mapping. These virtual models were then presented in AR for educational purposes.

RESULTS

Virtual representations in three dimensions were created to depict cadaver specimens, surgical approaches, patient surgical positions, and the operating room and laboratory environment. These models offer the flexibility of rotation and movement in various planes for improved visualization and understanding. The operating room and laboratory environment were rendered in three dimensions to create a simulation that could be navigated using AR and mixed reality technology. Realistic cadaveric models with intricate details were showcased on internet-based platforms and AR platforms for enhanced visualization and learning.

CONCLUSIONS

The utilization of this cost-effective, straightforward, and readily available approach to generate 3D models has the potential to enhance neuroanatomical and neurosurgical education. These digital models can be easily stored and shared via the internet, making them accessible to neurosurgeons worldwide for educational purposes.

The role of an open artificial intelligence platform in modern neurosurgical education: a preliminary study

The use of artificial intelligence in neurosurgical education has been growing in recent times. ChatGPT, a free and easily accessible language model, has been gaining popularity as an alternative education method. It is necessary to explore the potential of this program in neurosurgery education and to evaluate its reliability. This study aimed to show the reliability of ChatGPT by asking various questions to the chat engine, how it can contribute to neurosurgery education by preparing case reports or questions, and its contributions when writing academic articles. The results of the study showed that while ChatGPT provided intriguing and interesting responses, it should not be considered a dependable source of information. The absence of citations for scientific queries raises doubts about the credibility of the answers provided. Therefore, it is not advisable to solely rely on ChatGPT as an educational resource. With further updates and more specific prompts, it may be possible to improve its accuracy. In conclusion, while ChatGPT has potential as an educational tool, its reliability needs to be further evaluated and improved before it can be widely adopted in neurosurgical education.

Does the menstrual phase affect gastric emptying? Prospective, observational study

OBJECTIVE

Pulmonary aspiration of gastric content is a serious complication of anesthesia. It is unclear what effects different parts of the menstrual cycle have on how long it takes for the stomach to empty. This prospective observational study assessed the relationship between menstrual cycle phases and gastric emptying using ultrasonography (USG) in volunteers of reproductive age.

PATIENTS AND METHODS

Between days 8-10 of the menstrual cycle in the follicular phase and days 18-20 of the luteal phase, a total of 24 healthy volunteers received four stomach USG procedures. In both phases, the gastric antrum was evaluated with USG in the right lateral decubitus position after fasting for 10 hours, followed by 2 hours of fasting after liquid intake and 6 hours of fasting after solid food intake. The gastric content, gastric antrum area, and estimated gastric volume determined whether the stomach was full or empty.

RESULTS

A full stomach was detected in 8 (8.3%) out of 96 measurements performed on the volunteers. After liquid food intake, a full stomach was detected in 2 subjects in the luteal phase, while all the subjects had an empty stomach during the follicular phase (p=0.500). After solid food intake, a full stomach was detected in 6 subjects in the luteal phase, and again, all subjects had an empty stomach during the follicular phase (p=0.031).

CONCLUSIONS

Ultrasound assessment of gastric volume in volunteers of reproductive age has shown that gastric emptying of solid foods is slowed during the luteal phase of the menstrual cycle.

Stereotactic radiosurgery for cerebral cavernous malformation: comparison of hemorrhage rates before and after stereotactic radiosurgery

OBJECTIVE

Cerebral cavernous malformation (CM) is an angiographically occult vascular pathology. Although microsurgery is the gold standard treatment to control the symptoms of CM, resection carries high risk in some situations, especially eloquent areas. The objective was to evaluate annual hemorrhage rates (AHRs) before and after stereotactic radiosurgery (SRS) treatment of cerebral CM in different locations.

METHODS

A total of 195 patients (119 women and 76 men) with CM treated at the Gazi University Gamma Knife Center between April 2005 and June 2017 were analyzed. The mean ± SD follow-up period was 67.4 ± 31.1 months (range 12 days to 170 months). AHR before SRS, AHR after SRS, morbidity associated with radiation, seizure control rate after SRS, lesion volume, coexistence with developmental venous anomaly, and SRS treatment parameters were analyzed, with evaluation of radiological data and clinical charts performed retrospectively. The seizure control rate was assessed using the Engel outcome scale.

RESULTS

The AHR before SRS was 15.3%. Application of SRS to these patients significantly reduced the AHR rates to 2.6% during the first 2 years after treatment and to 1.4% thereafter. Favorable seizure control (Engel class I and II) after radiosurgery was achieved in 23 patients (88.5%) with epilepsy. Radiation-related temporary complications occurred in 15.4% of patients, and permanent morbidity occurred in 4.6%.

CONCLUSIONS

SRS is a safe and effective treatment modality for reducing the hemorrhage risk of CM. The authors suggest that SRS should be considered for the treatment of patients with CM, high surgical risks, and hemorrhage history, instead of a using a wait-and-see policy.

Different Aspects on Clinical Presentation of Developmental Venous Anomalies: Are They as Benign as Known? A Single Center Experience

BACKGROUND

Cerebral developmental venous anomalies (DVAs) are frequently diagnosed incidentally owing to the advances in neuroimaging. They are regarded as clinically insignificant due to their supposed quiescent existence which the authors aimed to contradict in this paper.

AIM

In the aim of constituting a better understanding of clinical presentation of DVAs and making an estimation regarding the probability of resulting in a hemorrhage, the authors presented their experiences with a case series of DVAs.

METHODS

A retrospective analysis was carried out among patients who underwent brain MRI in a radiology department of a university between January of 2019 and January of 2020.

RESULTS

A total of 101 patients with DVA were extracted. 38 patients had isolated DVAs, while 63 patients had various accompanying cerebral pathologies, mostly cavernomas (39 patients) and AVMs (11 patients). The main complaints leading investigation were headache, dizziness, ataxia, nausea\vomiting, seizures and focal neurological deficits. 41 patients were truly symptomatic with indicative findings of seizures, neurological deficits or intracranial hemorrhages, and 12 of them had solitary DVAs. 22 patients presented with hemorrhages, and of them, 10 had only DVA, while the rest had some associated lesions, most often cavernoma. Of 22 patients with hemorrhage, 5 were operated, 5 were applied radiosurgery; while the rest were followed without any intervention.

CONCLUSION

Although the symptoms in patients with DVA are generally charged on other associated pathologies, the fact that isolated DVAs may occasionally be problematic in the range of minor symptoms and severe hemorrhage should not be underestimated.

Polidocanol (Lauromacrogol 400) has anti-angiogenic effects in vitro and in vivo

OBJECTIVE

Polidocanol is the most frequently used sclerosant for sclerotherapy all around the world. Our experimental research aims to find out the angiogenic effects of Polidocanol.

MATERIALS AND METHODS

Angiogenic activity of polidocanol was examined in vivo in the chick chorioallantoic membrane (CAM) model, cell viability assay (human umbilical vein endothelial cells - HUVECs) and in vitro tube formation assay of HUVECs.

RESULTS

In CAM assay, a significant decrease on CAM vessel growth was observed after the application of polidocanol solutions. Vessel growth inhibition was strongly dose-dependent. There was a cytotoxic effect on HUVECs in the presence of polidocanol observed with MTT assay (p < 0.05). In the tube formation assay, statistically significant decrease in tube formation was observed in polidocanol group. It was found that polidocanol had an anti-angiogenic effect (p < 0.05). The results provide evidence that polidocanol decreases angiogenesis and has a cytotoxic effect on ECs.

CONCLUSIONS

These results provide evidence that Polidocanol (lauromacrogol 400) have strong anti-angiogenic effects in vitro and in vivo. Further researches needed to reveal early and long-term effects of polidocanol in the human vascular system and new treatment approach as an anti-angiogenic therapy.

Sedoanalgesia for cardioversion: comparison of alfentanil, remifentanil and fentanyl combined with propofol and midazolam: a prospective, randomized, double-blind study

OBJECTIVE

Electrical cardioversion (EC) is a short but painful procedure to restore sinus rhythm. The aim of this study is to compare the effect of fentanyl, remifentanil and alfentanil in association with propofol and midazolam for elective EC.

PATIENTS AND METHODS

Ninety-nine patients older than 18-years, American Society of Anesthesiologists I/II/III grades undergoing elective EC were randomized into 3 groups. All patients received 2 mg midazolam and propofol (0.5 mg/kg). Group A received alfentanil (5 µg/kg i.v. bolus), Group F received fentanyl (0.5 µg/kg i.v. bolus) and Group R received remifentanil (0.25 µg/kg i.v. bolus). Hemodynamics and respiratory variables [Heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), SpO2, respiratory rate (RR)], and Modified Aldrete recovery score (MARS) were assessed at six different time points (baseline, right after EC, and 3rd min, 5th min, 10th min, 30th min following EC). Also, induction times (time to reach RSS to 5) and recovery times (time to reach MARS to 8) were recorded. The incidence of respiratory depression, bradycardia, hypotension and adverse effects were also recorded.

RESULTS

Hemodynamic variables were similar in all groups. SpO2 values in Group R were significantly lower at 3rd min (p = 0.005). Induction and recovery times were longest in Group F. There were significant differences at 3rd, 5th and 10th minute MARS values between groups. The incidence of hypotension and bradycardia were similar in all groups (p > 0.05) but respiratory depression was higher in Group R (p = 0.047).

CONCLUSIONS

Propofol alfentanil combination has more beneficial advantages in their rapid onset, early recovery time and less respiratory depression than remifentanil and fentanyl.

In vitro effect of sodium nitrite on platelet aggregation in human platelet rich plasma--preliminary report

OBJECTIVE

The role of nitrates and nitric oxide on platelet functions has obtained an increasing attention with respect to their potential effects on cardiovascular disorders. In this study we aimed to analyze the effect of sodium nitrite on platelet functions in human platelets.

PATIENTS AND METHODS

This in vitro study was designed to show the effect of sodium nitrite on platelet functions in seven healthy volunteers. Blood samples were centrifuged to prepare platelet rich plasma and platelet poor plasma. Platelet rich plasma was diluted with the platelet poor plasma to have a final count of 300,000 ± 25,000 platelets. Platelet rich plasma was incubated with six different increasing doses (from 10 μM to 5 mM) of sodium nitrite for 1 hour at 37°C. Then stimulating agents including collagen (3 μg ml-1), adenosine diphosphate (10 μM), and epinephrine (10 μM) were added to the cuvette. Changes in light transmission were observed for 10 minutes. In addition spontaneous aggregation were performed in control group with all aggregating agents separately.

RESULTS

Effect of sodium nitrite on agonist-induced platelet aggregation depends on the concentration of sodium nitrite. Compared with control group, agonist-induced platelet aggregations were significantly suppressed by sodium nitrite at the concentration of 5, 1.0 and 0.5 mM.

CONCLUSIONS

Our results suggested that sodium nitrite has inhibitory effects in vitro on platelet aggregation in a dose-dependent manner.

New probing and warm-wash-out technique improves early patency rates in arteriovenous fistula surgery

OBJECTIVE

Arteriovenous fistulas (AVFs) are commonly used during hemodialysis. Early failure of AVFs is quite common with incidence of 43% to 63%. In this study we aimed to describe a novel approach to AVF surgery for improving early patency rates.

PATIENTS AND METHODS

Patients were divided into two groups according to use of probing and warm-wash-out technique. Group I consisted of 31 patients with additional probing technique. Group II consisted of 32 patients without additional maneuver. End-to-side anastomosis were used to all patients. Technical success was defined as having palpation of a thrill on fistula. Flow rates of draining vein was measured at 1st hour, 24th hour, 1st week and 3rd week of surgery.

SURGICAL TECHNIQUE

Classical maneuvers were performed until end of the anastomosis. At this time, vein lumen was washed by low-dosed heparinized warm fluid, with assistance of a simple catheter.

RESULTS

Technical success was similar in both groups at 1st hour and 24th hour, while there were significantly differences between groups at 1st week (p = 0.042) and 3rd week (p = 0.05) assessments. Flow rates were also measured significantly higher in Group I at 1st hour (p = 0.011) and 24th hour (p = 0.016). Flow rates were almost similar in two groups at 1st and 3rd weeks but overall success rate was higher in Group I comparing with Group II (96.8% vs. 81.3%, respectively, p = 0.05).

CONCLUSIONS

Probing and warm-wash out technique will simply increase the surgical success and flow rate of draining vein.

Comparison of angiogenic and proliferative effects of three commonly used agents for pulmonary artery hypertension (sildenafil, iloprost, bosentan): is angiogenesis always beneficial?

OBJECTIVE

Pulmonary artery hypertension (PAH) is devastating disease that has very serious outcomes. Dysregulated angiogenesis is one of the main responsible courses in pathophysiology of disease. Our experimental research intends to find out and compare the angiogenic effects of medications used sildenafil, iloprost, and bosentan in the treatment of PAH.

MATERIALS AND METHODS

This study was performed in Department of Biochemistry and Cancer and Stem Cell Research Laboratory of our institutes between August and October 2014. Angiogenic activity of sildenafil, iloprost, and bosentan were examined in vivo in chick chorioallantoic membrane (CAM) model and in vitro tube formation assay of human umbilical vein endothelial cells (HUVECs). Proliferative activity of these three agents was also determined through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay on HUVECs.

RESULTS

In CAM assay, when compared to the control and drug groups, treatment with sildenafil solutions resulted in a significant dose-dependent increase (budding, sprouting, extravasation) on CAM vessel growth. While there was no significant proliferative effect with iloprost and bosentan, presence of sildenafil caused a statistically significant proliferation on HUVECs following 24 and 48 h incubation (p < 0.05) compared to the control group. Comparing the tube length/area ratio values, there was statistically significant increase in sildenafil group with respect to the other 2 groups (p < 0.05). Iloprost and bosentan did not show a significant effect.

CONCLUSIONS

The results provide evidence that sildenafil but not iloprost and bosentan induces angiogenesis in vitro and in vivo. Dysregulated angiogenesis, as an important pathophysiological part in the progression of PAH, may be triggered by the chronic ingestion of sildenafil in the long treatment period and may cause negative effects.

p53 overexpression as a prognostic indicator in endometrial carcinoma

PURPOSE

To investigate the prognostic value of p53 overexpression in endometrial adenocarcinoma cases of different stages and histologic subtypes.

METHODS

One hundred and eleven surgically staged endometrial carcinoma (EC) cases from 1996 to 2000 constituted this retrospective study group. Prognostic factors determined through the evaluation of surgery specimens by co-author pathologist, were surgical stage, tumor size, histology, histologic and nuclear grade, myometrial invasion, adnexal/serosal metastasis, peritoneal cytology, retroperitoneal lymph node involvement p53 overexpression was assessed via immunohistochemical staining. Tissues that expressed p53 were considered as positive p53 staining. In terms of degree of staining, 1-29%, 30-90% and 80-100% of tumoral tissue stained with p53 were considered to be mild, moderate and high p53 staining, respectively.

RESULTS

Mean age and follow-up period of the study group were 58.2 +/- 10.6 years and 33.4 +/- 2.7 months, respectively. Percentages of cases surgically staged as early (I-II) and advanced (III-IV) FIGO stages were 65.8% (n: 73) and 34.2% (n: 38), respectively. Cases with positive p53 staining had a significantly high mean survival period compared with those with negative p53 staining (86.6 +/- 6.0 vs 49.1 +/- 8.1, p < 0.001). p53 overexpression was statistically detected to be high in Stage III-IV tumors, non-endometrioid histologic subtypes (p = 0.019), histologic and nuclear grade 2-3 tumors (p < 0.001), adnexal/serosal metastasis (p = 0.001), lymph node involvement (p = 0.012), and positive peritoneal cytology (p = 0.017). The degree of p53 staining was remarkably correlated with survival. In cases with mild and high p53 staining, mean survival times were 47.1 +/- 7.0 months and 57.0 +/- 13.1 months, respectively (p = 0.0003) compared to those with high p53 staining. On univariate analysis, all of the prognosticators, including p53 staining (p < 0.001) and degree of p53 staining (p < 0.001) appeared to be independent risk factors for poor prognosis. On multivariate analysis, only pelvic lymph node involvement (p = 0.03), serosal/adnexal involvement (p = 0.004), and positive peritoneal cytology (p = 0.01) were found to be independent prognosticators of survival while p53 expression (p = 0.743) and degree of p53 staining (p = 0.802) were not detected as independent prognosticators.

CONCLUSION

p53 overexpression is strongly related to poor prognostic indicators in endometrial adenocarcinoma. Although in this study p53 overexpression was not detected as an independent prognosticator, additional studies with large data set are needed to evaluate the prognostic value of p53 expression.