Risk Factors for Postoperative Cerebral Vasospasm After Surgical Resection of Acoustic Neuroma

Diluted intracisternal papaverine for microvascular protection of cranial nerves during vestibular schwannoma and cerebello-pontine angle surgery. Commentary and review of the literature

Vasospasm after resection of skull base tumors is a rare complication that often produces relevant ischemic sequelae. This review of the literature reports a number of published experiences that can help determine the potential causes of vasospasm after cerebello-pontine angle (CPA) tumor and -in particular-vestibular schwannoma (VS) resection, the ways to prevent it, and the methods to obtain the correct diagnosis. The cause appears to be multifactorial and the surgical approach may contribute to the pathogenesis of vasospasm. Neurosurgeons must pay attention to detect possible vasospasm at an early stage of cerebello-pontine. Cerebral blood flow measurement and transcranial Doppler are useful monitoring tools. Intra-operative prevention of vasospasm during CPA tumor resection with papaverine hydrochloride (PPV) seems to play a relevant role. In particular, PPV is a direct-acting vasodilator used to manage vasospasm during various neurosurgical operations. There is large uncertainty about intracisternal PPV dose-related efficacy and side effects. Dilution of PPV in saline prior to application is recommended to avoid complications. In our experience, in line with the literature, we use a pure PPV without excipients 60 mg/2 ml diluted in 20 cc of 0,9% saline solution (0,3%) to prevent Hearing Loss during Posterior Fossa Microvascular Decompression for Typical Trigeminal Neuralgia and other cranial nerves potentially involved during VS and other CPA tumor resection. The aim of this commentary is to analyze and discuss the role of diluted intracisternal PPV for microvascular protection of cranial nerves during CPA tumor surgery.

Symptomatic cerebral vasospasm following posterior fossa hemangioblastoma resection: illustrative case

BACKGROUND

Symptomatic cerebral vasospasm following posterior fossa intra-axial tumor resection is a rare phenomenon with only seven cases previously reported in the literature. The condition appears distinct to vasospasm following supratentorial tumor resection and extra-axial tumor resection of the posterior fossa. It shares, however, similarities with vasospasm following aneurysmal subarachnoid hemorrhage.

OBSERVATIONS

The authors describe their experience with a 23-year-old female who developed delayed symptomatic vasospasm following resection of a left parapontine cerebellar hemangioblastoma. Tumor resection was complicated by rupture of a fragile arterialized vein, resulting in significant hemorrhage. The patient developed several episodes of focal and variably reversible neurological deficit. These clinical signs corresponded with angiographically confirmed vasospasm, which responded to standard therapies for vasospasm post aneurysmal subarachnoid hemorrhage.

LESSONS

This case and literature review highlight that symptomatic vasospasm is a rare, potentially highly morbid complication of posterior fossa intra-axial tumor resection. This phenomenon may be related to significant intraoperative or postoperative hemorrhage. Postoperative radiological findings such as high risk modified Fisher scale hemorrhage could alert clinicians to this condition.

Failure of diffusion-weighted imaging in intraoperative 3 Tesla MRI to identify hyperacute strokes during glioma surgery

Intraoperatively acquired diffusion-weighted imaging (DWI) sequences in cranial tumor surgery are used for early detection of ischemic brain injuries, which could result in impaired neurological outcome and their presence might thus influence the neurosurgeon’s decision on further resection. The phenomenon of false-negative DWI findings in intraoperative magnetic resonance imaging (ioMRI) has only been reported in single cases and therefore yet needs to be further analyzed. This retrospective single-center study’s objective was the identification and characterization of false-negative DWI findings in ioMRI with new or enlarged ischemic areas on postoperative MRI (poMRI). Out of 225 cranial tumor surgeries with intraoperative DWI sequences, 16 cases with no additional resection after ioMRI and available in-time poMRI (< 14 days) were identified. Of these, a total of 12 cases showed false-negative DWI in ioMRI (75%). The most frequent tumor types were oligodendrogliomas and glioblastomas (4 each). In 5/12 cases (41.7%), an ischemic area was already present in ioMRI, however, volumetrically increased in poMRI (mean infarct growth + 2.1 cm³; 0.48–3.6), whereas 7 cases (58.3%) harbored totally new infarcts on poMRI (mean infarct volume 0.77 cm³; 0.05–1.93). With this study we provide the most comprehensive series of false-negative DWI findings in ioMRI that were not followed by additional resection. Our study underlines the limitations of intraoperative DWI sequences for the detection and size-estimation of hyperacute infarction. The awareness of this phenomenon is crucial for any neurosurgeon utilizing ioMRI.

Microvascular decompression for typical trigeminal neuralgia: Personal experience with intraoperative neuromonitoring with level-specific-CE-Chirp® brainstem auditory evoked potentials in preventing possible hearing loss

Background:

Permanent hearing loss after posterior fossa microvascular decompression (MVD) for typical trigeminal neuralgia (TTN) is one of the possible complications of this procedure. Intraoperative brainstem auditory evoked potentials (BAEPs) are used for monitoring the function of cochlear nerve during cerebellopontine angle (CPA) microsurgery. Level-specific (LS)-CE-Chirp® BAEPs are the most recent evolution of classical click BAEP, performed both in clinical studies and during intraoperative neuromonitoring (IONM) of acoustic pathways during several neurosurgical procedures.

Methods:

Since February 2016, we routinely use LS-CE-Chirp® BAEPs for monitoring the function of cochlear nerve during CPA surgery, including MVD for trigeminal neuralgia. From September 2011 to December 2018, 71 MVDs for TTN were performed in our department, 47 without IONM of acoustic pathways (Group A), and, from February 2016, 24 with LS-CE-Chirp BAEP (Group B).

Results:

Two patients of Group A developed a permanent ipsilateral anacusia after MVD. In Group B, we did not observe any permanent acoustic deficit after surgery. In one case of Group B, during arachnoid dissection, intraoperative LS-CE-Chirp BAEP showed a temporary lag of V wave, resolved in 5 min after application of intracisternal diluted papaverine (0.3% solution without excipients).

Conclusion:

MVD is widely considered a definitive surgical procedure in the management of TTN. Even though posterior fossa MVD is a safe procedure, serious complications might occur. In particular, the use of IONM of acoustic pathways during MVD for TTN might contribute to prevention of postoperative hearing loss.

Postoperative Neurological Complications after a Cranial Surgery: A Multicentre Prospective Observational Study

Background  Cranial surgery is associated with multiple postoperative complications varying from simple nausea and vomiting to devastating complications such as stroke and death. This multicentre collaborative effort was envisioned to collect observational data regarding postoperative complications in cranial surgeries among the Indian population. The aim of this study was to describe the postoperative neurological complications occurring within the first 24 hours after surgery and to identify the predictive factors.

Methods Data was collected from three participating tertiary care academic institutions. The study was prospective, observational, multicentre design with data collected over a period of two months or 100 cases, whichever is earlier, from each participating institute. A predesigned Microsoft excel sheet was distributed among all three centers to maintain uniformity. All patients aged 18 years and above of both sexes undergoing elective or emergency craniotomies were included in the study. The postoperative neurological complications (within 24 hours) assessed were: (1) Neurological deficit (ND) defined as new focal neurological motor deficit relative to preoperative status. (2) Sensorium deterioration (SD) defined as reduction in Glasgow coma score (GCS) by 2 or more points compared with preoperative GCS. (4) Postoperative seizures (SZs) defined as any seizure activity. All possible variables associated with the above neurological complications were tested using Chi-square/Fisher exact test or Mann–Whitney U test. The predictors, which were statistically significant at p < 0.2, were entered into a multiple logistic regression model. Alpha error of 5% was taken as significant.

Results Data from three institutions was collected with a total of 279 cases. In total, there were 53 (19%) neurological complications. There were 28 patients with new postoperative NDs (10.04%), 24 patients had SD (8.6%), and 17 patients had seizures (6.1%). Neurological deficits were significantly less in institution 2. Diagnosis of traumatic brain injury (TBI) was associated with very low risk of ND, and vascular pathology was associated with higher chance of a ND. The duration of anesthesia was found to be significantly predictive of SD (OR/CI = 1.01 / 1–1.02). None of the factors were predictive of PS.

Conclusion The incidences of postoperative ND, SD and postoperative seizures were 10%, 8.6%, and 6.1%, respectively. Studies with a much larger sample size are required for a better and detailed analysis of these complications.

Diffuse Cerebral Vasospasm After Removal of a Posterior Fossa Hemangioblastoma in a 62-Year-Old Woman

BACKGROUND

The development of diffuse cerebral vasospasm after the removal of a brain tumor is extremely rare. We report a case of cerebral vasospasm after the removal of a posterior fossa hemangioblastoma.

CASE DESCRIPTION

A 62-year-old woman presented with a 1-month history of vertigo and nausea. Neurologic examination revealed that she was alert, with no paresis, and a mild left-sided cerebellar ataxia. Contrast-enhanced magnetic resonance imaging showed a cystic lesion with a strongly enhancing nodule, measuring 20 × 26 mm in diameter, in the cerebellar dorsal vermis. Angiography revealed that the lesion had feeding arteries from the left posterior inferior cerebellar artery. A diagnosis of hemangioblastoma was suspected and surgery was performed. On the first postoperative day, paresis of the right-sided extremities occurred. Diffusion-weighted imaging showed a high-intensity area in the medial side of the left frontal lobe. Magnetic resonance angiography indicated diffuse cerebrovascular stenosis. Considering these findings to be caused by vasospasm, we started the treatment used for vasospasm secondary to aneurysmal subarachnoid hemorrhage. Magnetic resonance angiography on the 13th postoperative day revealed an improvement in the cerebrovascular stenosis. In this case, it appears that the cause of vasospasm was intraoperative spillage of the contents of the cyst.

CONCLUSIONS

Although the occurrence of diffuse cerebral vasospasm after the removal of brain tumors in the posterior fossa is rare, this complication should be noted as a potential postoperative complication after tumor removal; this should lead to earlier diagnosis and treatment and a potentially better prognosis.

Cerebral Vasospasm after Open Fenestration of an Arachnoid Cyst in a 4-Year-Old Boy: Case Report and Review of the Literature

Cerebral vasospasm is associated with significant morbidity, and most commonly occurs following subarachnoid hemorrhage. Rarely, vasospasm can follow tumor resection and traumatic brain injury. We present the first reported case of a young child who developed diffuse vasospasm following open fenestration of an arachnoid cyst and was promptly treated, with full recovery of neurologic function. Although vasopasm after arachnoid cyst fenestration is rare, it can be included in the differential for a new focal neurologic deficit.

Complicações pós-operatórias em neurocirurgia eletiva e não eletiva

Resumo Objetivo Avaliar a incidência de complicações pós-operatorias e mortalidade entre pacientes submetidos a neurocirurcia eletiva e não eletiva. Metodos Estudo de coorte prospectivo com pacientes adultos, acompanhados desde o período pré-operatório até a alta hospitalar ou óbito. Resultados Foram incluídos 127 pacientes no grupo cirúrgico eletivo e 75 pacientes no grupo cirúrgico não eletivo. O grupo eletivo teve mais vômitos (p=0,010) e dor (p<0,001) e o grupo não eletivo apresentou mais hipertensão intracraniana (p=0,001), anisocoria (p=0,002), vasoespasmo cerebral (p=0,043), pupilas não fotorreagentes (p=0,006) e reoperação (p=0,046). A taxa de mortalidade foi de 5,5% no grupo de cirurgia eletiva e 26,7% no grupo de cirurgia não eletiva (p<0,001). Conclusão Os procedimentos eletivos em neurocirurgia estão relacionados a maior frequência de complicações sistêmicas, enquanto as cirurgias não eletivas tiveram taxas significativamente mais altas de complicações neurológicas e mortalidade.

Predictors of Acute Vertebrobasilar Vasospasm following Tumor Resection in the Foramen Magnum Region

Objective

Cerebral vasospasm can occur after skull base tumor removal. Few studies concentrated on the posterior circulation vasospasm after tumor resection in the posterior fossa. We aimed to identify the risk factors associated with postoperative vertebrobasilar vasospasm after tumor resection in the foramen magnum.

Methods

We retrospectively reviewed the data of 62 patients with tumors in the foramen magnum at our institution from January 2010 to January 2015. The demographic data, tumor features, surgical characteristics were collected. Vertebrobasilar vasospasm was evaluated by bedside transcranial Doppler before surgery and on postoperative day 1, 3, 7. Univariate and multivariate analyses were performed to determine the predictors of postoperative vasospasm in the posterior circulation.

Results

Vertebrobasilar vasospasm was detected in 28 (53.8%) of the 62 patients at a mean time of 3.5 days after surgery. There were 5 (8%) patients with severe vasospasm according to the grading criteria. Age, tumor type, tumor size, vertebral artery encasement, and surgical time were significantly related to vasospasm in the univariate analysis. Further multivariate analysis demonstrated that only age and vertebral artery encasement were independent risk factors predicting the occurrence of postoperative vertebrobasilar vasospasm.

Conclusions

The incidence of acute vertebrobasilar vasospasm is not uncommon after foramen magnum tumor resection. Age and vertebral artery encasement are significantly correlated with postoperative vasospasm. Close monitoring of vasospasm should be given to patients with younger age and the presence of vertebral artery encasement on the preoperative imaging to facilitate early diagnosis and intervention.