Resection Of Brainstem Cavernomas Research Articles

Holmes tremor: a delayed complication after resection of brainstem cavernomas.

In this paper, the authors aimed to illustrate how Holmes tremor (HT) can occur as a delayed complication after brainstem cavernoma resection despite strict adherence to the safe entry zones (SEZs). After operating on 2 patients with brainstem cavernoma at the Great Metropolitan Hospital Niguarda in Milan and noticing a similar pathological pattern postoperatively, the authors asked 10 different neurosurgery centers around the world to identify similar cases, and a total of 20 were gathered from among 1274 cases of brainstem cavernomas. They evaluated the tremor, cavernoma location, surgical approach, and SEZ for every case. For the 2 cases at their center, they also performed electromyographic and accelerometric recordings of the tremor and evaluated the post-operative tractographic representation of the neuronal pathways involved in the tremorigenesis. After gathering data on all 1274 brainstem cavernomas, they performed a statistical analysis to determine if the location of the cavernoma is a potential predicting factor for the onset of HT. From the analysis of all 20 cases with HT, it emerged that this highly debilitating tremor can occur as a delayed complication in patients whose postoperative clinical course has been excellent and in whom surgical access has strictly adhered to the SEZs. Three of the patients were subsequently effectively treated with deep brain stimulation (DBS), which resulted in complete or almost complete tremor regression. From the statistical analysis of all 1274 brainstem cavernomas, it was determined that a cavernoma location in the midbrain was significantly associated with the onset of HT (p < 0.0005). Despite strict adherence to SEZs, the use of intraoperative neurophysiological monitoring, and the immediate success of a resective surgery, HT, a severe neurological disorder, can occur as a delayed complication after resection of brainstem cavernomas. A cavernoma location in the midbrain is a significant predictive factor for the onset of HT. Further anatomical and neurophysiological studies will be necessary to find clues to prevent this complication.

Erratum. Holmes tremor: a delayed complication after resection of brainstem cavernomas.

Erratum. Holmes tremor: a delayed complication after resection of brainstem cavernomas.

Functional DTI tractography in brainstem cavernoma surgery

OBJECTIVE Surgical resection of brainstem cavernomas is associated with high postoperative morbidity due to the density of local vulnerable structures. Classical mapping of pathways by diffusion tensor imaging (DTI) has proven to be unspecific and confusing in many cases. In the current study, the authors aimed to establish a more reliable, specific, and objective method for somatotopic visualization of the descending motor pathways with navigated transcranial magnetic stimulation (nTMS)–based DTI fiber tracking. METHODS Twenty-one patients with brainstem cavernomas were examined with nTMS prior to surgery. The resting motor threshold (RMT) and cortical representation areas of hand, leg, and facial function were determined on both hemispheres. Motor evoked potential (MEP)–positive stimulation spots were then set as seed points for tractography. Somatotopic fiber tracking was performed at a fractional anisotropy (FA) value of 75% of the individual FA threshold. RESULTS Mapping of the motor cortex and tract reconstruction for hand, leg, and facial function was successful in all patients. The somatotopy of corticospinal and corticonuclear tracts was also clearly depicted on the brainstem level. Higher preoperative RMT values were associated with a postoperative motor deficit (p &lt; 0.05) and correlated with a lower FA threshold (p &lt; 0.05), revealing structural impairment of the corticospinal tract (CST) prior to surgery. In patients with a new deficit, the distance between the lesion and CST was below 1 mm. CONCLUSIONS nTMS-based fiber tracking enables objective somatotopic tract visualization on the brainstem level and provides a valuable instrument for preoperative planning, intraoperative orientation, and individual risk stratification. nTMS may thus increase the safety of surgical resection of brainstem cavernomas.

Resection of Mesencephalic Cavernoma Using the "Half-and-Half" Approach: 2-Dimensional Operative Video.

Brainstem cavernous malformations present a particular challenge to neurosurgeons. Their deep location and proximity to critical brainstem nuclei and fiber tracts make surgical access challenging. Despite this, microsurgical resection of brainstem cavernomas has been associated with good long-term neurological outcome, albeit with notable (but temporary) perioperative morbidity. Here, we demonstrate the microsurgical resection of a mesencephalic cavernoma via a "half-and-half" approach. Described as the temporopolar approach by Sano in 1980,1 this approach centers on the oculomotor nerve and combines the transsylvian and pre-/subtemporal corridors. A wide opening of the Sylvian fissure and posterior mobilization of the temporal lobe permits access to the interpenducular cistern, mesencephalon and rostral pons. In this way, the "half-and-half" ideally suited for lesions of the anterior and antero-lateral brainstem. While temporary postoperative oculomotor nerve palsy is not uncommon, rapid resolution is expected. Verbal consent was provided by the patient for reproduction and publication of her case.

Brainstem cavernous malformations: Experience case series

Objective: The purpose of this single centre retrospective study is to provide an institutional review of surgically treated brainstem cavernous malformations. Methods: The clinical experience from January 2013 to September 2014 is evaluated. All medical records and images were reviewed in order to retrieve the most important data regarding epidemiology, clinical picture, radiological findings and surgical outcomes. Results: Eight patients (5 female and 3 male) underwent surgical resection of brain stem cavernoma to alleviate the symptoms caused by brain stem cavernoma. Age ranged from 19 to 53 years (mean 34 years). Headache was common symptom followed by cranial nerve deficit. Seven patients had one or more episodes of haemorrhage documented by magnetic resonance imaging. Pons was the most common location. Surgery was performed under microsurgical conditions with endoscopic assistance, using neuronavigation, and neurophysiological monitoring. After resection during follow-up, 5 patients had improvement in the modified Rankin scale. The preoperative average Rankin score was 1.75 points and had improved at the last follow up (minimum follow up six months) by 0.63 points. Conclusions: Brain stem cavernomas can be resected safely with surgical approach using meticulous microsurgical technique surgical approach. The additional use of modern tools such as neuronavigation, endoscopic assistance, and monitoring can contribute to the safety of the procedure. Goal of surgical intervention to achieve the complete resection of the lesion, without any neurological impairment. Keywords: brain stem; cavernoma; Rankins scale

Poor diagnostic accuracy of transcranial motor and somatosensory evoked potential monitoring during brainstem cavernoma resection.

Microsurgical resection of brainstem cavernomas carries a high risk of new postoperative morbidity such as cranial nerve, motor and sensory deficits as well as functional deterioration. Intraoperative monitoring is used to avoid impending damage to these highly eloquent tracts. However, data on neurophysiological monitoring during resection of brainstem cavernomas are lacking. Consecutive patients with brainstem cavernomas who underwent surgical removal from June 2007 to December 2014 were retrospectively analysed. Transcranial motor-evoked potential (MEP) and somatosensory-evoked potential (SSEP) monitorings were performed in all cases. The evoked potential (EP) monitoring data were reviewed and related to new postoperative motor and sensory deficits and postoperative imaging. Clinical outcomes were assessed during follow-up. Twenty-six consecutive patients with brainstem cavernoma underwent 27 surgical resections within this study. MEP and SSEP monitoring was technically feasible in 26 and 27 cases, respectively. MEP sensitivity and specificity were 33 and 88 %, respectively. MEP positive and negative predictive values were 28 and 78 %, respectively. SSEP sensitivity and specificity were 20 and 81 %, respectively. SSEP positive and negative predictive values were 20 and 81 %, respectively. In continuous MEP and SSEP monitoring during brainstem cavernoma microsurgery, high rates of false-positive and -negative results are encountered, resulting in low positive and relatively high negative predictive values. Careful interpretation of the intraoperative monitoring results is essential in order to avoid potentially unjustified termination of brainstem cavernoma resection.

Brainstem cavernoma surgery with the support of pre- and postoperative diffusion tensor imaging: initial experiences and clinical course of 23 patients.

The spatial complexity of highly vulnerable structures makes surgical resection of brainstem cavernomas (BSC) a challenging procedure. Diffusion tensor imaging (DTI) allows for the visualization of white matter tracts and enables a better understanding of the anatomical location of corticospinal and sensory tracts before and after surgery.We investigated the feasibility and clinical usefulness of DTI-based fiber tractography in patients with BSC.Pre- and postoperative DTI visualization of corticospinal and sensory tracts were retrospectively analyzed in 23 individuals with BSC. Preoperative and postoperative DTI-fiber accuracy were associated to the neurological findings. Preoperatively, the corticospinal tracts were visualized in 90 % of the cases and the sensory tracts were visualized in 74 % of the cases. Postoperatively, the corticospinal tracts were visualized in 97 % of the cases and the sensory tracts could be visualized in 80 % of the cases. In all cases, the BSC had caused displacement, thinning, or interruption of the fiber tracts to various degrees. Tract visualization was associated with pre- and postoperative neurological findings. Postoperative damage of the corticospinal tracts was observed in two patients. On follow-up, the Patzold Rating (PR) improved in 19 out of 23 patients (83 %, p = 0.0002).This study confirms that DTI tractography allows accurate and detailed white matter tract visualization in the brainstem, even when an intraaxial lesion affects this structure. Furthermore, visualizing the tracts adjacent to the lesion adds to our understanding of the distorted intrinsic brainstem anatomy and it may assists in planning the surgical approach in specific cases.

Surgical management of brainstem cavernomas: selection of approaches and microsurgical techniques

This study reviewed surgical experience with brainstem cavernomas in an attempt to define optimal surgical approaches and risks associated with surgical management. Clinical courses were retrospectively reviewed for 36 consecutive patients (12 men, 24 women; mean age, 42 years) who underwent microsurgical resection of brainstem cavernomas between 1996 and 2006. Medical records, surgical records, and neuroimaging examinations were evaluated. All 36 patients presented with > or =1 hemorrhage from the cavernomas and preoperatively displayed some neurological symptoms. Surgical approach was midline suboccipital for 16 pontine and/or medullary cavernomas under the floor of the fourth ventricle, retrosigmoid for 10 lateral mesencephalic, pontine, and/or medullary cavernomas, occipital transtentorial for 2 thalamomesencephalic and 3 mesencephalic cavernomas, combined petrosal for 2 pontine cavernomas, and other for 3 cavernomas. Complete resection according to postoperative magnetic resonance imaging was achieved in 33 of 36 patients. No mortality was encountered in this study. New neurological deficit occurred in the early postoperative period for 18 patients, but was transient in 15 of these. Neurological state as of final follow-up was improved in 16 patients (44%), unchanged in 17 (47%), and worsened in 3 (8%) compared with preoperatively. In conclusion, symptomatic brainstem cavernomas should be considered for surgical treatment. Careful selection of the optimal operative approach and a meticulous microsurgical technique are mandatory.

Microroll retractor for surgical resection of brainstem cavernoma

Background Safe and complete surgical resection of brainstem cavernoma is difficult without injury surrounding normal structures because the lesions are deep and intra-axial. In this article, the authors describe the “microroll retractor” technique for brainstem cavernoma surgery. Methods The microroll retractor is made of expanded polytetrafluoroethylene sheet. The sheet is cut in several sizes of square piece and transformed into a tubular shape. We insert this roll retractor via minimal brain incision and keep surgical corridor without usual spatulas during lesionectomy. Results This technique was adopted for 7 patients with brainstem cavernomas. In all patients, we achieved total excision; improvement was recorded in 6 patients, and no change was recorded in 1 patient. Conclusions The microroll retractor is extremely simple but provides enough surgical corridors for safe total resection of brainstem cavernomas.

Experience of microsurgical treatment of brainstem cavernomas: Report of 37 cases

Cavernomas are rare in the brainstem and account for 18-35% of central nervous cavernomas and can cause recurrent hemorrhages, devastating neurological deficits and mortality. To summarize the experience of microsurgical treatment of brainstem cavernomas and to investigate curative effect of microsurgical treatment of brainstem cavernomas. A retrospective analysis clinical data of 37 patients with brainstem cavernomas seen between 2003 and 2007. The analysis included age distribution, hemorrhage rates, clinical presentation, location of the lesions, and preoperative and postoperative Karnofsky Performance Scale (KPS) scores. The surgical indications, the timing of surgery and the surgical techniques were also assessed. All the 37 patients received microsurgical resections, there was no surgery-related mortality. Histopathological examination confirmed the diagnosis of cavernoma. Postoperatively, 20 patients had functional improvement, 15 patients had no change in the neurological status, and two patients deteriorated. Early surgery was associated with better outcomes. Mean followed up period was 21.5 months (range 6-36 months). During the follow-up 20 patients had resumed activities of daily living (KPS scores of 90-100), 10 patients were able to self-care with some efforts (KPS scores of 70-80), five patients needed considerable assistance (KPS score of 50-60) and two patients suffered hemiparesis (KPS scores of 40). None of the patient had recurrent hemorrhage. Brainstem cavernomas can safely be resected. Successful resection of brainstem cavernomas can be achieved by optimal surgical approaches, feasible entry zone and meticulous microsurgical techniques. The goal of surgical intervention should be the total resection of the lesion without any deteriorative in the neurological deficits.

Surgical management of brainstem cavernomas.

A careful retrospective analysis of 36 cases was performed to evaluate the pre- and postoperative rates of morbidity that occur in patients with brainstem cavernous angiomas. The authors evaluated immediate postoperative and follow-up outcomes with regard to clinical findings, the incidence of preoperative hemorrhage(s), location and size of the lesions, and the timing of the surgical procedure after the last hemorrhagic event. Specifically. the following parameters were analyzed: 1) number of hemorrhages; 2) the precise brainstem location (pontomesencephalic, pons, and medulla oblongata); 3) pre- and postoperative cranial nerve status; 4) pre- and postoperative motor and sensory deficits; 5) size (volume) of the lesions; and 6) pre- and postoperative Karnofsky Performance Scale (KPS) scores. Multiple hemorrhages were observed in 16 patients, particularly in those with pontomesencephalic cavernous angiomas (75%). The mean preoperative KPS score was 70.3 +/- 16.3 (+/- standard deviation). Twenty-six patients (72.2%) presented with cranial nerve impairment, 13 (36.1%) with motor deficits, and 17 (47.2%) with sensory disturbance. Volume of the lesions ranged from 0.18 to 18.18 cm3 (mean 4.75 cm3). Postoperative complications included new cranial nerve deficits in 17 patients, motor deficits in three, and new sensory disturbances in 12 patients. In a mean follow-up period of 21.5 months, KPS scores were 80 to 100 in 22 patients. Timing of surgery (posthemorrhage) and multiple hemorrhages did not influence the long-term results. Higher preoperative KPS scores and smaller-volume lesions, however, were factors associated with a better final outcome (p < 0.05). Major morbidity was related mainly to preoperative status and less to surgical treatment. The incidence of new postoperative cranial nerve deficits was clearly lower than that demonstrated preoperatively because of the brainstem hemorrhages. Based on these findings, resection of brainstem cavernomas is the treatment of choice in the majority of these cases because of the high incidence of morbidity related to one or often several brainstem hemorrhages.