|Year : 2019 | Volume
| Issue : 2 | Page : 557-560
Surgical treatment of brainstem cavernous malformation with concomitant developmental venous anomaly
Vania Bozhidarova Georgieva, Emil Dimitrov Krastev
Department of Neurosurgery, Sofiamed Hospital, Sofia University St. Kliment Ohridski, Sofia, Bulgaria
|Date of Web Publication||26-Apr-2019|
Vania Bozhidarova Georgieva
Department of Neurosurgery, Sofiamed Hospital, Sofia University St. Kliment Ohridski, 1000, Sofia
Source of Support: None, Conflict of Interest: None
Surgical resection of brainstem cavernous malformations (BCMs) is a high-risk procedure and can be challenging to the neurosurgeon. Lateral surgical routes are becoming increasingly used to approach ventrolaterally brainstem cavernoma. Surgical approach decision depends on the location of the cavernoma in the brainstem and a possible association with brainstem developmental venous anomalies (DVAs). DVA can affect the formation and clinical course of cavernous malformation (CM). CMs related to DVAs tend to have more aggressive behavior than isolated CM. In cases of DVAs associated with hemorrhage, CMs are most often the site of bleeding rather than DVAs themselves. In this case report, we present a 24-year-old woman with a pontomedullary CM and associated dorsally located DVA. BCM was operated through a far lateral suboccipital craniotomy. Brainstem entry point was at inferior olive with extension to the pontomedullary sulcus. This approach should be preferred as a safe surgical exposure to the central and paramedian pontomedullary cavernoma, especially in the cases with associated intraparenchymal brainstem DVA. Such surgical exposure allows preservation of the concomitant brainstem DVA.
Keywords: Brainstem cavernoma, developmental venous anomalies, far lateral approach, hemorrhage
|How to cite this article:|
Georgieva VB, Krastev ED. Surgical treatment of brainstem cavernous malformation with concomitant developmental venous anomaly. Asian J Neurosurg 2019;14:557-60
|How to cite this URL:|
Georgieva VB, Krastev ED. Surgical treatment of brainstem cavernous malformation with concomitant developmental venous anomaly. Asian J Neurosurg [serial online] 2019 [cited 2019 Nov 15];14:557-60. Available from: http://www.asianjns.org/text.asp?2019/14/2/557/252954
| Introduction|| |
Cavernous malformations (CMs) of the central nervous system have an estimated prevalence of 0.4%–0.9% in the general population.,, Brainstem cavernous malformations (BCMs) are rare and account for 8%–22% of all intracranial cavernomas. Bleeding and rebleeding (recurrent hemorrhages) rates of BCMs are substantially higher than cavernomas in other locations., Hemorrhages from BCs are never clinically silent comparing with some cerebral cavernomas. They cause severe neurological deficits mainly due to repeated hemorrhages. Developmental venous anomalies (DVAs) are the most frequently encountered common form of vascular malformations. The reported incidence is 2.6% on autopsy studies, but with the use of modern imaging techniques, the prevalence is estimated to be much higher (6.4%). Posterior fossa is a frequent location of DVAs, but drainage through the brainstem is exceptional finding. CMs associated with a DVAs have a more aggressive clinical course and are more likely to present with symptomatic hemorrhage than CMs alone. The goal of operative intervention in such association is complete resection of the CM with preservation of the associated venous anomaly. The experience of many surgeons has shown that these veins drain normal tissue and their obliteration can lead to venous infarcts. We present a case of a brainstem pontomedullary cavernoma with concomitant venous anomaly operated through a far lateral suboccipital craniotomy and transolivar approach. Complete excision of the lesion in the medulla was achieved, and gliotic tissue at the pontine level around the abnormal vein was left in order to preserve the associated venous anomaly.
| Case Report|| |
A 24-year-old female patient presented with a sudden onset of nausea as well as head-and-neck pain 2 weeks before recent admission. She reported hypoesthesia on the left side of the body, left arm, and leg. Clinical examination revealed also unstable gait and weakness in the left leg. Magnetic resonance imaging (MRI) exam revealed a brainstem cavernoma located in the medulla and lower pons with signs of recent bleeding [Figure 1]a. At the same level, a prominent vein could be seen near the floor of the fourth ventricle [Figure 1]b,[Figure 1]c,[Figure 1]d, draining blood from radiating small veins of the pons and cerebellar peduncles. These small vessels constituted a pontomedullary DVA [Figure 1]e and [Figure 1]f. The symptoms could be related to bleeding of the cavernoma.
|Figure 1: (a) Magnetic resonance imaging T2-weighted sagittal image shows pontomedullary cavernoma after recent bleeding, (b-d) magnetic resonance imaging T1-weighted images with gadolinium. Medullary veins of the pontomedullary developmental venous anomaly exits dorsally to the cavernoma in a large collecting vein near the floor of the fourth ventricle (arrows), and (e and f) magnetic resonance imaging T1-weighted axial images with gadolinium. Transparenchymal small veins – tributaries of the developmental venous anomaly (arrowheads). A large collector draining vein running toward the cerebellomedullary fissure (arrow)|
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The patient was placed in the three-fourths prone (“park bench”) position with the head flexed and rotated 45° away from the lesion and laterally flexed downward toward the floor. A far lateral approach was used to expose the occipital bone and suboccipital region from the right side as well as the posterior elements of C1. C1 laminectomy, lateral occipital craniotomy, and condylectomy were performed. After opening of the tonsillomedullary fissure and gently retraction of the tonsil vagoaccessory triangle was approached. A brainstem incision (entry point) was performed on the inferior olive up to the pontomedullary sulcus. Cavernoma excision was performed leaving a part of the gliotic tissue and hemosiderosis in the pons to prevent DVA tributaries damage. Intraoperative brainstem auditory-evoked responses and motor-evoked responses did not show any disturbance.
She had postoperative dysphagia, hoarseness, and right cranial nerve VI palsy at the 1st month after the operation. A nasogastric tube was used during this period until the dysphagia had completely resolved. Two months later, the patient was almost asymptomatic with gait disturbance. A year after the operation, the symptoms resolved completely.
Postoperative imaging showed complete excision of the lesion in the medulla. Surrounded gliotic and hemosiderin-laden tissue at the pontine level was left in the order to preserve the associated DVA [Figure 2]a,[Figure 2]b,[Figure 2]c and [Figure 3]. The patient was informed for the estimated individual rebleeding risk and, in addition, all treatment options and possible morbidities related to them. There was no evidence of recurrent hemorrhage during the first 3 years after the operation.
|Figure 2: (a-c) Postoperative magnetic resonance imaging T1-weighted sagittal (a) and axial (b and c) images with gadolinium show residual gliotic hemosiderin tissue (arrow) around the small veins – tributaries of the developmental venous anomaly (arrowheads)|
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|Figure 3: Postoperative magnetic resonance imaging T1-weighted coronal image with gadolinium shows developmental venous anomaly tributaries preservation (arrow)|
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| Discussion|| |
BCMs are associated with severe neurological deficits and repeated hemorrhages. After the initial hemorrhage, the rebleeding rate increases to 45% per person per year.,, Currently, patients with significant neurological deficits and cavernoma coming up to the pial or ependymal surface are surgically treated. Although there is a morbidity rate mainly related to surgical experience,, the long-term outcomes in nonsurgical groups tend to be worse than in surgically treated patients.,,,
Coexistence between cerebral vascular malformation is not an unusual finding. There has been reported association between DVAs and CMs in approximately 13%–40% of cases.,, DVAs are considered to be anatomical variant of medullary veins. They represent a compensatory venous drainage system due to aplasia, hypoplasia, or early occlusion of normally developing veins., Although DVAs are benign lesions, they can affect the formation and clinical course of associated CMs. There have been case reports of de novo development of CMs in the drainage territory of DVAs.,, CMs related to DVAs tend to have more aggressive behavior than isolated CMs. In a recent study with persons younger than 45, the presence of a CM in the infratentorial region and the existence of a DVA are key independent hemorrhage risk predictors that may have a key role in treatment decision. In the case presently reported, we believe that cavernoma resection reduces the venous pressure in the concomitant DVA and facilitates venous drainage of the brainstem.
MRI combined with magnetic resonance angiography (MRA) replaces angiography in most cases of DVAs and CMs as a noninvasive alternative., In the presented case, MRI and MRA were used for the initial diagnosis. Follow-up MRI and MRA proved convenient for long-term follow-up of the patient.
Multiple surgical approaches have been proposed for BCMs. Most of them are exposed through the following approach: the orbitozygomatic pterional approach, supracerebellar infratentorial approach, retrosigmoid approach, midline suboccipital craniotomy (with or without telovelar dissection), and far lateral approach.
The central and deep paramedian parts of the medulla and pons are difficult locations for surgical exposure. Central and paramedian pontomedullary CMs are often accessed through a retrosigmoid exposure and a transmiddle cerebellar peduncle approach., Dissection through middle cerebellar peduncle continues approximately 1 cm to reach central or paramedian pons. This could be hazardous for patients with central pontomedullary cavernoma and concomitant deep situated DVA in the brainstem draining through the vein of the middle cerebellar peduncle such in the presented case. Such exposure carries additional high risk from venous brainstem infarction. A recently developed approach through pontomedullary sulcus could be popularized in such cases with relatively low morbidity and mortality rates. In the presented case, the entry point in the brainstem was through the superior part of inferior olive up to the pontomedullary sulcus. The trajectory passes through the upper part of the vagoaccessory triangle laterally to hypoglossal nerve rootlets, laterally to abducens nerve, and inferomedially to vestibulocochlear and facial nerves. The incision on inferior olive with an extension of the incision in the pontomedularry sulcus expanses the surgical exposure to central and paramedian parts of the medulla and the pons simultaneously.
In the presented case, there was a pontine residual cevernoma next to the main drainage of the DVA. Conservative observation and follow-up MRI investigations were performed. We decided that a possible reoperation carries an additional high risk for venous brainstem infarction. There was a nonaggressive appearance of the residual lesion on the MRI and a conservative management was selected in this special case. Three years after the operation, she had no evidence of recurrent hemorrhage.
| Conclusion|| |
Inferior olive approach with extension to the pontomedullary sulcus is a safe surgical exposure to the central and paramedian pontomedullary cavernoma. This approach should be preferred, especially in the cases with associated transparenchymal brainstem DVA. Surgical excision of BCMs associated with DVA is related with risk of venous brainstem infarction. Preservation of the associated DVA is mandatory. Such an association could affect the treatment decision.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Del Curling O Jr., Kelly DL Jr., Elster AD, Craven TE. An analysis of the natural history of cavernous angiomas. J Neurosurg 1991;75:702-8.
Katzman GL, Dagher AP, Patronas NJ. Incidental findings on brain magnetic resonance imaging from 1000 asymptomatic volunteers. JAMA 1999;282:36-9.
Bertalanffy H, Benes L, Miyazawa T, Alberti O, Siegel AM, Sure U, et al.
Cerebral cavernomas in the adult. Review of the literature and analysis of 72 surgically treated patients. Neurosurg Rev 2002;25:1-53.
Fritschi JA, Reulen HJ, Spetzler RF, Zabramski JM. Cavernous malformations of the brain stem. A review of 139 cases. Acta Neurochir (Wien) 1994;130:35-46.
Porter PJ, Willinsky RA, Harper W, Wallace MC. Cerebral cavernous malformations: Natural history and prognosis after clinical deterioration with or without hemorrhage. J Neurosurg 1997;87:190-7.
Porter RW, Detwiler PW, Spetzler RF, Lawton MT, Baskin JJ, Derksen PT, et al.
Cavernous malformations of the brainstem: Experience with 100 patients. J Neurosurg 1999;90:50-8.
Sarwar M, McCormick WF. Intracerebral venous angioma. Case report and review. Arch Neurol 1978;35:323-5.
Gökçe E, Acu B, Beyhan M, Celikyay F, Celikyay R. Magnetic resonance imaging findings of developmental venous anomalies. Clin Neuroradiol 2014;24:135-43.
Küker W, Mull M, Thron A. Developmental venous anomalies of the posterior fossa with transpontine drainage: Report of 3 cases. Eur Radiol 1997;7:913-7.
Wurm G, Schnizer M, Fellner FA. Cerebral cavernous malformations associated with venous anomalies: Surgical considerations. Neurosurgery 2005;57:42-58.
Asaad WF, Walcott BP, Nahed BV, Ogilvy CS. Operative management of brainstem cavernous malformations. Neurosurg Focus 2010;29:E10.
Garcia RM, Ivan ME, Lawton MT. Brainstem cavernous malformations: Surgical results in 104 patients and a proposed grading system to predict neurological outcomes. Neurosurgery 2015;76:265-77.
Li D, Hao SY, Jia GJ, Wu Z, Zhang LW, Zhang JT, et al.
Hemorrhage risks and functional outcomes of untreated brainstem cavernous malformations. J Neurosurg 2014;121:32-41.
Washington CW, McCoy KE, Zipfel GJ. Update on the natural history of cavernous malformations and factors predicting aggressive clinical presentation. Neurosurg Focus 2010;29:E7.
Bertalanffy H, Gilsbach JM, Eggert HR, Seeger W. Microsurgery of deep-seated cavernous angiomas: Report of 26 cases. Acta Neurochir (Wien) 1991;108:91-9.
Samii M, Eghbal R, Carvalho GA, Matthies C. Surgical management of brainstem cavernomas. J Neurosurg 2001;95:825-32.
Chen L, Zhao Y, Zhou L, Zhu W, Pan Z, Mao Y, et al.
Surgical strategies in treating brainstem cavernous malformations. Neurosurgery 2011;68:609-20.
San Millán Ruíz D, Delavelle J, Yilmaz H, Gailloud P, Piovan E, Bertramello A, et al.
Parenchymal abnormalities associated with developmental venous anomalies. Neuroradiology 2007;49:987-95.
Huber G, Henkes H, Hermes M, Felber S, Terstegge K, Piepgras U, et al.
Regional association of developmental venous anomalies with angiographically occult vascular malformations. Eur Radiol 1996;6:30-7.
Ostertun B, Solymosi L. Magnetic resonance angiography of cerebral developmental venous anomalies: Its role in differential diagnosis. Neuroradiology 1993;35:97-104.
Mullan S, Mojtahedi S, Johnson DL, Macdonald RL. Cerebral venous malformation-arteriovenous malformation transition forms. J Neurosurg 1996;85:9-13.
Saito Y, Kobayashi N. Cerebral venous angiomas: Clinical evaluation and possible etiology. Radiology 1981;139:87-94.
Maeder P, Gudinchet F, Meuli R, de Tribolet N. Development of a cavernous malformation of the brain. AJNR Am J Neuroradiol 1998;19:1141-3.
Cakirer S. De novo
formation of a cavernous malformation of the brain in the presence of a developmental venous anomaly. Clin Radiol 2003;58:251-6.
Campeau NG, Lane JI. De novo
development of a lesion with the appearance of a cavernous malformation adjacent to an existing developmental venous anomaly. AJNR Am J Neuroradiol 2005;26:156-9.
Kashefiolasl S, Bruder M, Brawanski N, Herrmann E, Seifert V, Tritt S, et al.
Abenchmark approach to hemorrhage risk management of cavernous malformations. Neurology 2018;90:e856-63.
Abe T, Singer RJ, Marks MP, Norbash AM, Crowley RS, Steinberg GK, et al.
Coexistence of occult vascular malformations and developmental venous anomalies in the central nervous system: MR evaluation. AJNR Am J Neuroradiol 1998;19:51-7.
Abla AA, Turner JD, Mitha AP, Lekovic G, Spetzler RF. Surgical approaches to brainstem cavernous malformations. Neurosurg Focus 2010;29:E8.
Abla AA, Lekovic GP, Turner JD, de Oliveira JG, Porter R, Spetzler RF, et al.
Advances in the treatment and outcome of brainstem cavernous malformation surgery: A single-center case series of 300 surgically treated patients. Neurosurgery 2011;68:403-14.
Adib AA, Benet A, Lawton MT. The far lateral transpontomedullary sulcus approach to pontine cavernous malformations: Technical report and surgical results. Oper Neurosurg 2014;10:472-80.
[Figure 1], [Figure 2], [Figure 3]