Monitored Anesthesia Care Protocol for Awake Craniotomy and Patient's Perspective on the Procedure

OBJECTIVE

There is ongoing discussion on pros and cons in terms of different anesthesia protocols for awake craniotomy (AC) with direct brain stimulation. The aim of this study is to share our anesthesia protocol and present our patients' perspectives.

METHODS

We conducted an analysis of prospectively collected data from 53 (54 procedures) consecutive patients. Most of the patients (50) underwent surgery due to primary brain lesions. Eight procedures were performed in patients with lesions in the nondominant hemisphere for language. Four of all procedures were reoperations, and one patient was operated on in awake conditions twice. The psychological evaluation of patients was performed 2 times: 2 days before and after surgery. A visual analog scale for pain and stress levels as well as structured interviews was used.

RESULTS

Most patients tolerated ACwell. Patients reported that discomfort was mostly related to urinary catheter insertion, head holder placement, and temporal muscle detachment in cases of frontotemporal craniotomies. The intensity of stress measured with the visual analog scale before surgery was negatively associated with age and positively correlated with stress experienced in the operating room. In all patients, we were able to finish the procedure according to the monitored anesthesia care protocol without the need for conversion to general anesthesia. We observed 3 (5.6%) intraoperative seizures that required deepening of sedation.

CONCLUSION

AC using the monitored anesthesia care protocol was a safe and well-tolerated procedure with satisfactory patient experience. Extensive preoperative preparation should be considered a key part of the procedure.

Long-Term Management of Seizures after Surgical Treatment of Supratentorial Cavernous Malformations : A Retrospective Single Centre Study

Objective

Seizure recurrence after the first-ever seizure in patients with a supratentorial cerebral cavernous malformation (CCM) is almost certain, so the diagnosis and treatment of epilepsy is justified. The optimal method of management of these patients is still a matter of debate. The aim of our study was to identify factors associated with postoperative seizure control and assess the surgical morbidity rate.

Methods

We retrospectively analysed 45 consecutive patients with a supratentorial CCM and symptomatic epilepsy in a single centre. Pre- and postoperative epidemiological data, seizure-related patient histories, neuroimaging results, surgery details and outcomes were obtained from hospital medical records. Seizure outcomes were assessed at least 12 months after surgery.

Results

Thirty-five patients (77.8%) were seizure free at the long-term follow-up (Engel class I); six (13,3%) had rare, nocturnal seizures (Engel class II); and four (8.9%) showed meaningful improvement (Engel class III). In 15 patients (33%) in the Engel I group; it was possible to discontinue antiepileptic medication. Although there was not statistical significance, our results suggest that patients can benefit from early surgery. No deaths occurred in our study, and mild postoperative neurologic deficits were observed in two patients (4%) at the long-term follow-up.

Conclusion

Surgical resection of CCMs should be considered in all patients with a supratentorial malformation and epilepsy due to the favourable surgical results in terms of the epileptic seizure control rate and low postoperative morbidity risk, despite the use of different predictors for the seizure outcome.

Anatomy of the occipital lobe using lateral and posterior approaches: a neuroanatomical study with a neurosurgical perspective on intraoperative brain mapping

BACKGROUND

A major concern of occipital lobe surgery is the risk of visual field deficits. Extending anatomical occipital lobectomy to the functional requires awake conditions because the anterior resection border comprises language-, motor- and visuospatial function-related areas within the temporal and parietal lobes. This study investigated the lateral and posterior perspectives of the occipital lobe anatomy when approaching intraaxial occipital lobe lesions.

MATERIALS AND METHODS

Ten adult cadaveric cerebral hemispheres were dissected after being prepared following the concept described by Klingler for the first time.

RESULTS

The occipital lobe was located posteriorly to the parietotemporal line. Within the occipital lobe, the occipital horn of the lateral ventricle represented the only anatomical landmark. Laterally, optic radiation was identified as a part of the sagittal stratum. None of the intraoperatively identifiable tracts was found medial to the occipital horn. Language- and motor-related areas were identified anteriorly and should be actively identified when lobectomy based on function is planned. Subcortically, from a posterior perspective, the anterolateral border constituted the arcuate fascicle/superior longitudinal fascicle complex and was anteromedial to the thalamocortical tract. Remaining posterior to the line connecting the preoccipital notch with the superior Rolandic point avoided the cortical and white matter tracts related to language, motor and visuospatial function.

CONCLUSIONS

Knowledge of occipital lobe anatomy and surrounding structures is essential to preoperatively assess the risk of the procedure and proper consultation of a patient in terms of the extent of resection, primarily concerning visual field deficits.

Awake intraoperative mapping to identify cortical regions related to music performance: Technical note

The aim of this manuscript is to present our intraoperative technique assessing the ability to perform music. Our protocol excludes cases where performance can be disrupted by motor deficits. The positive cortical sites (the posterior part of the superior temporal gyrus and supramarginal gyrus) related purely to music performance are also reported. We present the case of a patient, an amateur piano player who underwent surgery for a symptomatic supratentorial cavernoma while awake with intraoperative brain mapping. This case report shows that amateur and possibly professional musicians may benefit from awake procedures. This report confirms that stimulation of the specific area of the brain can disturb the function of a large network responsible for high-level cognitive task, like music performance.

White matter dissection with the Klingler technique: a literature review

The aim of this literature review is to present a summary of the published literature relating the details of the different modifications of specimen preparation for white matter dissection with the Klingler technique. For this review, 3 independent investigators performed an electronic literature search that was carried out in the Pubmed, Scopus and Web of Science databses up to December 2019. Furthermore, we performed citation tracking for the articles missed in the initial search. Studies were eligible for inclusion when they reported details of at least the first 2 main steps of Klingler's technique: fixation and freezing. A total of 37 full-text articles were included in the analysis. We included original anatomical studies in which human white matter dissection was performed for study purposes. The main three steps of preparation are the same in each laboratory, but the details of each vary between studies. Ten percent formalin is the most commonly used (34 studies) solution for fixation. The freezing time varied between 8 h and a month, and the temperature varied from - 5 to - 80 °C. After thawing and during dissections, the specimens were most often kept in formalin solution (13), and the concentration varied from 4 to 10%. Klingler's preparation technique involves three main steps: fixation, freezing and thawing. Even though the details of the technique are different in most of the studies, all provide subjectively good quality specimens for anatomical dissections and studies.

Microsurgical resection of symptomatic intramedullary cervical spinal cord cavernous malformation

Intramedullary cavernous malformations account for approximately 5% of all intraspinal lesions. Symptomatic lesions are treated with microsurgical resection. Due to surrounding eloquent spinal neural tissue, surgical removal of these lesions can be technically challenging. Surgical treatment carries a significant risk for postoperative morbidity. This video demonstrates the main steps for the microsurgical technique of resection of a symptomatic intramedullary cervical spinal cord cavernous malformation at the C2–3 level. Complete resection was achieved with minimal posterior column deficit. The operative technique and surgical nuances, including the patient’s positioning, surgical approach, intraspinal cavernous malformation removal, and closure, are illustrated.

The video can be found here: https://youtu.be/UKttTiXlEb8.

Morphometric Analysis for Surgical Treatment of Cervical Discopathy by Posterior Laminoforaminotomy: Radiologic Study and Technical Note

BACKGROUND

The main concern with the posterior approach is the risk of postoperative segmental instability. The most commonly cited rule is that removal of the medial half of the articular facet provides adequate surgical exposure and has no effect on stability. The aim of this study was to define the areas of the articular processes in the cervical spine that can be safely removed.

METHODS

Computed tomography scans of 50 cervical spines were analyzed. Measurements were analyzed for bone removal assuming the standard technique of posterior laminoforaminotomy. The width of the facet was measured at the level of the widest dimension. The height of the articular process was taken from the bottom (in the case of inferior process) or top (in the case of superior process) of the process.

RESULTS

The mean width of the articular process ranged from 11.8 ± 1.5 mm (range, 8.3-15.7 mm) at the C2-C3 level to 14.6 ± 1.7 mm at the C6-C7 level. At the cervicothoracic junction (C7-T1 level), the mean width decreased to 14.0 ± 1.7 mm. The mean value for both sides when the inferior articular process was measured at all levels was 5.0 ± 1.4 mm (range, 4.5-5.8 mm). The mean height of the superior articular process was 7.7 ± 1.5 mm (range, 6.8-8.3 mm).

CONCLUSIONS

Based on our findings, our "5-5-7 mm rule" corresponds to the amount of bone removal for each step of the laminoforaminotomy.

Hemihypoglossal-Facial Nerve Anastomosis for Facial Nerve Reanimation: Case Series and Technical Note

BACKGROUND

Hypoglossal nerve injury may result in swallowing and speech problems. To reduce this morbidity and allow the performance of the hypoglossal-facial nerve anastomosis bilaterally, a technique that includes partial splitting of the hypoglossal nerve and skeletonization of the facial nerve within the mastoid process has been applied. The aim of this study is to present clinical results regarding the facial and hypoglossal nerves after the procedure.

METHODS

Prospectively collected data from 56 consecutive patients who underwent hemihypoglossal-facial nerve anastomosis (HHFA) were analyzed. The outcome was correlated with epidemiologic data, initial disease, the presence of neurofibromatosis type 2, previous radiosurgery, and the time between nerve injury and reconstructive surgery.

RESULTS

Forty-eight (84%) patients achieved satisfactory outcomes; 8 of them (14%) showed some improvement, and in 1 patient (2%) there was no improvement during long-term observation. The result at follow-up was not related to the time interval between the 2 procedures. However, recovery times for facial tonicity were statistically significantly longer if the procedure was performed after 12 months (P = 0.044). There was no statistically significant association between patient age (P = 0.96) or sex (P = 0.13) and facial nerve function. HHFA resulted in no or minimal tongue atrophy without deviation in 53 patients (93%), and the remainder had mild hemiatrophy with tongue deviation <30 degrees.

CONCLUSIONS

HHFA is an effective technique for facial nerve reanimation with acceptable morbidity related to tongue function. Patients with a longer duration of facial palsy still have a good chance for restoration of facial movement but require longer recovery periods.

Results of hemihypoglossal-facial nerve anastomosis in the treatment of facial nerve paralysis after failed stereotactic radiosurgery for vestibular schwannoma

Vestibular schwannoma treatment with stereotactic radiosurgery (SRS) carries a risk of facial nerve (CNVII) palsy that is lower than that with microneurosurgery. The results of hemihypoglossal-facial nerve anastomosis (HHFA) have not been described yet in CNVII palsy after failed stereotactic radiosurgery (SRS). Here we report a case series of the first four consecutive patients (three women; average age 58.5, age range: 46-74), who underwent HHFA due to failed SRS. All patients were admitted because of progressive peripheral facial nerve palsy. Three patients received retrosigmoid craniotomy due to tumor enlargement that resulted in facial nerve paralysis. All patients achieved satisfactory (House-Brackmann grade III) CNVII regeneration. No or minimal tongue atrophy occurred on the side of the anastomosis. Patients reported no problems with phonation or swallowing, except for the patients with preexisting lower cranial nerve deficits. HHFA effectively treats facial palsy after failed SRS with minimal risk of tongue atrophy and minimal morbidity. The results of the treatment are comparable to those achieved with patients without previous SRS.

Endoscopic endonasal approach to the lateral orbital apex: case report

Although the medial and inferior orbital apex are considered safely accessible using the endonasal endoscopic approach, the lateral apex has been considered unsafe to access since the optic nerve lies between the surgeon and the pathology. The authors present the case of a 4-year-old girl with recurrent rhabdomyosarcoma attached to the lateral rectus muscle located lateral and inferior to the optic nerve in the orbital apex. The tumor was totally resected through an endoscopic endonasal transmaxillary transpterygoidal approach using a 45° endoscope. A gross-total resection was achieved, and the patient's vision was unchanged. This procedure is a safe, minimal-access alternative to open procedures in selected cases and provides evidence that increases the applicability of the endonasal endoscopic approach to reach the lateral compartment of the orbital apex.