A systematic review of published evidence on expanded endoscopic endonasal skull base surgery and the risk of postoperative seizure

Postoperative Epileptic Seizures in Children

Background: Postoperative seizures (PS) occur in 10−15% of patients. This study aims to provide an update on the role of surgery in PS. Methods: All children undergoing a craniotomy for supratentorial lesions in the last 10 years were considered except those with preoperative seizures, perioperative antiepileptic drugs prophylaxis, head-injury and infections, repeated surgery, or preoperative hyponatremia. Children undergoing surgery for intra-axial lesions (Group 1, 74 cases) were compared with those harboring extra-axial lesions (Group 2, 91 cases). Results: PS occurred in 9% of 165 cases and epilepsy in 3% of 165 cases (mean follow-up: 5.7 years). There was no difference between the two study groups with regard to demographic data or tumor size. Group 1 showed a higher rate of gross total tumor resection (p = 0.002), while Group 2 had a higher rate of postoperative hyponatremia (p < 0.0001). There were no differences between the two groups in the occurrence of seizures (6.7% vs. 11%) or epilepsy (2.7% vs. 3.2%). No correlations were found between seizures and age, tumor location, histotype, tumor size, or the extent of tumor resection. Hyponatremia affected the risk of PS in Group 2 (p = 0.02). Conclusions: This study shows a lower rate of PS and epilepsy than series including children with preoperative seizures. Hyponatremia has a significant role. Neurosurgery is safe but surgical complications may cause late epilepsy.

Heterogeneity in Outcome Reporting in Endoscopic Endonasal Skull Base Reconstruction: A Systematic Review

Objective  Presently, there are no standards for reporting outcomes of endoscopic endonasal skull base reconstruction (ESBR). This is problematic as a lack of consistent reporting makes synthesizing findings in systematic reviews and meta-analysis challenging. Thus, the aim of this study was to systematically review and describe the patterns of reporting outcomes in ESBR as a foundation for developing reporting guidelines. Study Design  Present study is a systematic review. Methods  Embase, PubMed, CINAHL, Cochrane Library, and Web of Science were searched for all publications with ≥25 patients and a focus on ESBR. The reporting patterns of each study's variables and outcomes were assessed. Results  A total of 112 studies were included in the review. The most commonly reported demographic variables were the number of included patients ( n  = 112, 100%) and types of pathologies treated ( n  = 104, 92.9%). Meanwhile, the most routinely described preoperative variable was history of prior treatment ( n  = 48, 42.9%). Type of reconstruction was a commonly reported intraoperative variable ( n  = 110, 98.2%), though the rate of intraoperative cerebrospinal fluid (CSF) leak was noted in only 76 studies (67.9%). With regard to postoperative outcomes, postoperative CSF leak rate was routinely provided ( n  = 101, 90.2%), but reporting of other surgical complications was more inconsistent. Ultimately, of the 43 variables and outcomes reviewed, a median of 12 (range: 4-22) was reported in each study. Conclusion  There is significant heterogeneity in the outcomes reported in studies relating to ESBR. This highlights the need for the development of standard reporting guidelines to minimize bias and improve interstudy comparability.

Seizure Risk following Open and Expanded Endoscopic Endonasal Approaches for Intradural Skull Base Tumors

Objectives  The incidence of seizures following a craniotomy for tumor removal varies between 15 and 20%. There has been increased use of endoscopic endonasal approaches (EEAs) for a variety of intracranial lesions due to its more direct approach to these pathologies. However, the incidence of postoperative seizures in this population is not well described. Methods  This is a single-center, retrospective review of consecutive patients undergoing EEA or open craniotomy for resection of a cranial base tumor between July 2007 and June 2014. Patients were included if they underwent an EEA for an intradural skull base lesion. Positive cases were defined by electroencephalograms and clinical findings. Patients who underwent a craniotomy to remove extra-axial skull base tumors were analyzed in the same fashion. Results  Of the 577 patients treated with an EEA for intradural tumors, 4 experienced a postoperative seizure (incidence 0.7%, 95% confidence interval [CI]: 0.002-0.02). Over the same period, 481 patients underwent a craniotomy for a skull base lesion of which 27 (5.3%, 95% CI: 0.03-0.08) experienced a seizure after surgery. The odds ratio for EEA was 0.13 (95% CI: 0.05-0.35). Both populations were different in terms of age, gender, tumor histology, and location. Conclusion  This study is the largest series looking at seizure incidence after EEA for intracranial lesions. Seizures are a rare occurrence following uncomplicated endonasal approaches. This must be tempered by selection bias, as there are inherent differences in which patients are treated with either approach that influence the likelihood of seizures.

Seizure outcomes of supratentorial brain tumor resection in pediatric patients

Background

This study aims to identify the prevalence of and risk factors for seizure development after supratentorial brain tumor resection in pediatric patients. This could be used to guide the postoperative management and usage of anti-epileptic drugs (AEDs).

Methods

Retrospective study was conducted for patients between 0 and 21 years with supratentorial tumor resection between 2005 and 2015 at a single institution.

Results

Two hundred patients (114 males/86 females) were identified. Median age at resection (±SD) was 9.025 ± 5.720 years and mean follow-up was 4 ± 2 years. Resection was gross total in 82 patients (41%) and partial in 118 patients (59%); 66 patients (33%) experienced preoperative seizures, and 67 patients (34%) experienced postoperative seizures; 18 patients (27%) had early seizures, and 49 patients (73%) had late seizures. Univariate analysis identified risk factors for postoperative seizures as: preoperative seizures (P < 0.001), age less than 2 years (P = 0.003), temporal location (P < 0.001), thalamic location (P = 0.017), preoperative hyponatremia (P = 0.017), World Health Organization grade (P = 0.008), and pathology (P = 0.005). Multivariate regression identified 5 robust risk factors: temporal location (odds ratio [OR] 4.7, 95% CI: 1.7-13.3, P = 0.003), age <2 years (OR 3.9, 95% CI: 1.0-15.4; P = 0.049), preoperative hydrocephalus (OR 3.8, 95% CI: 1.5-9.4; P = 0.005), preoperative seizure (OR 2.8, 95% CI: 1.2-6.5; P = 0.016) and parietal location (OR 0.25, 95% CI: 0.06-0.99; P = 0.049). Extent of resection did not correlate with seizure development (P > 0.05).

Conclusions

This study reveals 5 risk factors for postoperative seizures after resection of supratentorial tumors. These factors should be considered in postoperative management of these patients.

Postoperative Epileptic Seizures in Children: Is the Brain Incision a Risk Factor?

BACKGROUND

Postoperative seizures (PSs) after neurosurgical operations are common but little is known about the role of surgical brain incision on their genesis. This topic has not been addressed so far.

OBJECTIVE

To verify if the corticotomy affects the risk of PSs and postoperative epilepsy (PE) in children.

METHODS

One hundred forty-three consecutive pediatric cases operated on for supratentorial lesions at the same institution in the last 15 yr have been retrospectively reviewed by dividing them into group A, 68 children who required brain corticotomy mainly for hemispheric tumors, and group B, 75 children treated through extracortical approaches mainly for suprasellar and optic tumors. Patients with possible "epileptic" biases, like preoperative seizures, were excluded.

RESULTS

No significant differences have been found between group A and B as far as incidence of PSs (11.7% vs 14.5%) and PE (4.5% vs 6.5%), timing, and type of seizures are concerned after a mean 6.8 yr follow-up. The size of corticotomy in group A (<3 cm2 vs >3 cm2) had no impact on epileptogenesis as well as the other variables considered in both groups (age, sex, extent of lesion resection).

CONCLUSION

This study shows that the surgical cortical "trauma" would not represent a risk factor for PSs and PE. According to the present analysis and the literature, other causes seem to be involved (namely, electrolytic imbalance and brain gliosis). This information is important for preoperative surgical planning and postoperative management. A validation by both adult series and prospective studies is needed.

The Expanded Endoscopic Endonasal Approach to Anterior Communicating Artery Aneurysms: A Cadaveric Morphometric Study

OBJECTIVE

The purpose of this study was to explore the endoscopic endonasal approach to the anterior communicating artery complex.

DESIGN

Anatomic, morphometric analysis of human cadaver heads.

SUBJECTS

Fifteen latex-injected adult cadaver heads.

MAIN OUTCOME MEASURES

The anatomic boundaries of the operative field and the dimensions of exposure of the anterior communicating artery (ACoA) complex were measured and clip placement feasibility was assessed.

RESULTS

Exposure of the ACoA and bilateral A1 and A2 segments was accomplished in all 15 cadaver heads. Average length of the exposed ACoA was 3 ± 1 mm, the left A1 was 5 ± 3 mm and right A1 was 5 ± 1 mm, while the A2 segment was 5 ± 2 mm bilaterally. The average distance from the alar floor to the ACoA was 95 mm, while proximal lateral limit measured between the alar floor margins was 36 mm. The distal lateral limit as defined by the distance between the lateral most exposed margins of the chiasm was 19 mm. Clip placement was accomplished for the ACoA and the A1 and A2 segments bilaterally in all specimens.

CONCLUSION

The endoscopic, endonasal transtuberculum, transplanum approach is an anatomically feasible alternative to treating select aneurysms of the ACoA complex.

Frontobasal Midline Meningiomas: Is It Right To Shed Doubt on the Transcranial Approaches? Updates and Review of the Literature

BACKGROUND

Traditionally, the surgical removal of tuberculum sellae meningioma (TSM) and olfactory groove meningioma (OGM) requires transcranial approaches and microsurgical techniques, but in the last decade endoscopic expanded endonasal approaches have been introduced: transcribriform for OGMs and transtuberculum-transplanum for TSM. A comparative analysis of the literature concerning the two types of surgical treatment of OGMs and TSM is, however, difficult.

METHODS

We conducted a literature search using the PubMed database to compare data for endoscopic and microsurgical techniques in the literature. We also conducted a retrospective analysis of selected cases from our series presenting favorable characteristics for an endoscopic approach, based on the criteria of operability of these lesions as generally accepted in the literature, and we compared the results obtained in these patients with those in the endoscopic literature.

RESULTS

We believe that making the sample more homogeneous, the difference between microsurgical technique and endoscopic technique is no longer so striking. A greater radical removal rate, a reduced incidence of cerebrospinal fluid fistula and, especially, the possibility of removing lesions of any size are advantages of transcranial surgery; a higher percentage of improvement in visual outcome and a lower risk of a worsening of a pre-existing deficit or onset of a new deficit are advantages of the endoscopic technique.

CONCLUSION

At present, the microsurgical technique is still the gold standard for the removal of the anterior cranial fossa meningiomas of all sizes, and the endoscopic technique remains a second option in certain cases.

Endoscopic endonasal transplanum approach to the paraclinoid internal carotid artery

Objective To investigate the relevance of an endoscopic transnasal approach to the surgical treatment of paraophthalmic aneurysms. Setting Binasal endoscopic transplanum surgery was performed. Participants Seven cadaver heads were studied. Main Outcome Measures (1) Dimensions of the endonasal corridor, including the operative field depth, lateral limits, and the transplanum craniotomy. (2) The degree of vascular exposure. (3) Surgical maneuverability and access for clip placements. Results The mean operative depth was 90 ± 4 mm. The lateral corridors were limited proximally by the alar rim openings (29 ± 4 mm) and distally by the distance between the opticocarotid recesses (19 ± 2 mm). The mean posteroanterior distance and width of the transplanum craniotomy were 19 ± 2 mm and 17 ± 3 mm, respectively. Vascular exposure was achieved in 100% of cases for the clinoidal internal carotid artery (ICA), ophthalmic artery, superior hypophyseal artery, and the proximal ophthalmic ICA. Surgical access and clip placement was achieved in 97.6% of cases for vessels located anterior to the pituitary stalk (odds ratio [OR] 73.8; 95% confidence interval [CI] 7.66 to 710.8; p = 0.00). Conclusion The endoscopic transnasal approach provides excellent visualization of the paraclinoid region vasculature and offers potential surgical alternative for paraclinoid aneurysms.