Cavernomas of the central nervous system: clinical syndromes, CT scan diagnosis, and prognosis after surgical treatment in 25 cases

MRI Diagnosis of Brainstem Cavernous Angiomas Presenting as Tumours

We report experience with 11 patients misdiagnosed for years, on the basis of computed tomography (CT) and angiography, as harbouring brainstem tumours in whom magnetic resonance imaging (MRI) demonstrated cavernous angiomas. Seven had undergone external irradiation, 2 had a ventriculo-peritoneal shunt, 2 developed aseptic femur necrosis following corticosteroid treatment, 1 had undergone a biopsy with a pathological diagnosis of glioma. CT had depicted ill-defined, hyperdense, faintly enhancing lesions. Angiography was normal, or showed an avascular mass or subtle venous pooling. MRI delineated discrete lesions, typical of cavernous angiomas, with a mixed hyperintense, reticulated, central core surrounded by a hypointense rim. Six patients subsequently underwent stereotactic radiosurgery without changes in clinical status or lesion. Although hemorrhagic neoplasms may mimic the clinical course and MRI appearance of cavernous angiomas, MRI is useful in the diagnosis of brainstem cavernous angiomas and should be performed in patients with suspected brainstem tumours.

Surgical treatment of symptomatic cerebral cavernous malformations in eloquent brain regions

BACKGROUND

Despite the increased risk of hemorrhage and deteriorating neurological function of once-bled cerebral cavernous malformations (CM), the management of eloquently located CMs remains controversial.

METHODS

All eloquently located CMs (n = 45) surgically treated between 03/2006 and 04/2011 in our department were consecutively evaluated. Eloquence was characterized according to Spetzler and Martin's definition. The following locations were approached: brainstem, n = 16; sensorimotor, n = 8; visual pathway, n = 7; cerebellum (deep nuclei and peduncles), n = 7; basal ganglia, n = 4, and language, n = 3. Follow-up data was available for 41 patients (91 %) with a median interval of 14 months. Outcomes were evaluated according to the Glasgow outcome and the modified Rankin scale.

RESULTS

Immediately after surgery, 47 % (n = 21) had a new deficit. At follow-up, 80 % (n = 36) recovered to at least preoperative status or were better than before surgery, 9 % (n = 4) exhibited a slight, and 7 % (n = 3) had a moderate neurological impairment. Only two cases (4 %) with a new permanent severe deficit were observed, both related to dorsal brainstem surgery. The outcome after the surgery of otherwise located brainstem CMs was as beneficial as that for non-brainstem CMs. Patients with initially poor neurological performance fared worse than oligosymptomatic patients.

CONCLUSIONS

Despite the high postoperative transient morbidity, the majority improved profoundly during follow-ups. Compared with natural history, surgical treatment should be considered for all eloquent symptomatic CMs. Dorsal brainstem location and poor preoperative neurological status are associated with an increased postoperative morbidity.

Treatment strategies in cavernomas of the brain and spine

The management of brain and spinal cavernomas includes two main options: (i) conservative treatment or (ii) surgical removal. Clinical experience related to cavernoma patients falls into four major categories: the surgical or conservative treatment of incidental or symptomatic cavernomas. In many patients, cavernomas exist as fairly benign lesions, frequently remaining clinically silent for life. This observation argues against the active treatment of all cavernoma patients; rather for the meticulous selection of only those more likely to benefit from surgery. Thus, the most crucial task in successful management of cavernomas is appropriate patient selection. In this review, we present our institutional experience on cavernoma management supplemented with data from the literature.

Cerebral cavernous malformations: spectrum of neuroradiological findings

Cavernous malformations (cavernomas) are hamartomatous lesions formed by sinusoidal vascular spaces, with no cerebral parenchyma between them. Seizures are the most usual clinical presentation. They are dynamic lesions, producing changes throughout their evolution. The majority are located in the supratentorial region, but up to 20% of cases they are found in the posterior fossa. In computed tomography (CT) and in magnetic resonance (MR) their typical presentation is as a well defined round or oval lesion, with or without a minimal mass effect or oedema, with little or no contrast enhancement. Their appearance in MRI will depend on the stage of the haemorrhage, a T2 echo gradient being the most sensitive sequence. Angiography do not usually detect cavernomas. However, it may demonstrate a venous developmental anomaly. Cavernomas may present with atypical characteristics, as regards their size, appearance, location and number.

The presigmoid approach to anterolateral pontine cavernomas. Clinical article

OBJECT

Anterolateral cavernomas of the pons have been surgically removed via a variety of approaches, commonly retrosigmoid or transventricular. The goal in this study was to evaluate the presigmoid approach as an alternative.

METHODS

Clinical data were reviewed in 9 patients presenting with anterolateral pontine cavernomas between 1999 and 2007.

RESULTS

All patients were treated via a presigmoid approach, which provided a nearly perpendicular trajectory to the anterolateral pons. The brainstem was entered through a "safe zone" between the trigeminal nerve and the facial/vestibulocochlear nerve complex. Complete resection was achieved in all cases. No patient experienced recurrent events during follow-up (1-24 months). The patients' modified Rankin Scale score improved within 1 year of surgery (1.7 ± 0.4) compared with baseline (2.6 ± 0.2; p < 0.05). Only one patient experienced a new deficit (decreased hearing), which was corrected with a hearing aid.

CONCLUSIONS

The presigmoid approach is recommended for the resection of anterolateral pontine cavernomas. With this approach, the need for cerebellar retraction is nearly eliminated. The lateral "presigmoid" entry point creates a trajectory that allows complete resection of even deep lesions at this level, or anterior to the internal acoustic meatus.

CAVERNOUS MALFORMATIONS OF THE BASAL GANGLIA AND THALAMUS

CAVERNOUS MALFORMATIONS OF the basal ganglia and thalamus present a unique therapeutic challenge to the neurosurgeon given their unclear natural history, the risk of surgical treatment, and the unproven efficacy of radiosurgical therapy. Via a PubMed search of the English and French literature, we have systematically reviewed the natural history and surgical and radiosurgical management of these lesions reported through April 2008. Including rates cited for “deep” cavernous malformations, annual bleeding rates for these lesions varied from 2.8% to 4.1% in the natural history studies. Across surgical series providing postoperative or long-term outcome data on 103 patients, we found an 89% resection rate, a 10% risk of long-term surgical morbidity, and a 1.9% risk of surgical mortality. The decrease in hemorrhage risk reported 2 years after radiosurgery might be a result of natural hemorrhage clustering, underscoring the unproven efficacy of this therapeutic modality. Given the compounded risks of radiation-induced injury and post-radiosurgical rebleeding, radiosurgery at modest dosimetry (12–14 Gy marginal doses) is only an option for patients with surgically inaccessible, aggressive lesions.

SYMPTOMATIC BRAINSTEM CAVERNOMAS

OBJECTIVE

The goal of this study was to analyze the natural history of symptomatic brainstem cavernomas (medulla, pons, or midbrain) and outcome after surgical resection.

METHODS

We retrospectively analyzed clinical data of all patients who presented to our institution with symptomatic brainstem cavernomas between 1995 and 2007 (n = 44).

RESULTS

After a first neurological event, the median event-free interval was 2 years, with an annual event rate of 42%. After a second neurological event (new neurological deficit or significant worsening of the previous deficit), the median event-free interval was only 5 months, with a monthly event rate of 8%. After an observation period of up to 8 years, all patients ultimately underwent surgery. In 95% of the patients, surgery successfully prevented further events during a median follow-up period of 11 months (1 month–7 years; P &lt; 0.001). The postoperative event rate was 5% per year in the first 2 years and 0% thereafter. In the multivariate analysis, only the preoperative modified Rankin scale score was predictive of the surgical outcome (odds ratio, 36.7; P = 0.015). The conditions of 2 patients (5%) were clinically worse compared with their preoperative conditions during the 1-year follow-up period; in one of these patients, this was caused by recurrent events. There was no mortality.

CONCLUSION

The event rate of symptomatic lesions seems to be high, particularly after recurrent events. Surgical morbidity can be low. Timely and complete surgical resection is recommended for symptomatic brainstem cavernomas to prevent patients' functional decline owing to recurrent events.

Cavernous angiomas of the brain stem and spinal cord

This article reviews the pathology, clinical course and management of cavernous angiomas in the brain stem and spinal cord. Both lesions have been diagnosed with increasing frequency as a result of magnetic resonance image scanning. Brain stem lesions tend to present dramatically; their treatment remains microsurgical excision despite some studies that have looked at the use of radiosurgery. Spinal lesions are either extra-, or more commonly, intramedullary. Intramedullary cavernomas present with a wide spectrum of symptoms ranging from acute haematomyelia to presentations that mimic demylelinating conditions; extramedullary cavernous angiomas tend to produce radicular symptoms or subarachnoid haemorrhage. Both are treated by microsurgical excision.

[Neurosurgical treatment of patients with supratentorial cavernoma]

The aim of this study is to present the principal clinical manifestations and neurosurgical results of the treatment of patients with supratentorial cavernoma and epilepsy. The retrospective study included 14 patients with supratentorial lesion on MRI and CT scan of the brain that manifested with epileptic seizures. All patients were surgically treated and pathophysiologic evaluation in all patients confirmed that cavernoma was in question. Results were analyzed and compared with data from the literature. Epileptic seizures are the most frequent clinical manifestation found in supratentorial cavernoma and neurosurgical treatment gives excellent result as regards the control of epilepsy, with a very low incidence of morbidity and mortality. A complete resection of all cavernomas in this study was confirmed by postoperative neurosurgical diagnosing. 12 patients did not have any more epi seizures in the postoperative period, and in 2 patients we found decrease in the occurrence of epilepsy seizures.

Cavernomes profonds (corps calleux, intraventriculaires, ganglions de la base, insulaires) et du tronc cérébral. Expérience d'une série brésilienne

With a review of the literature, we report our experience with surgical treatment of deep-seated cavernomas (intraventricular, of the corpus callosum, the capsula interna, the insula and the brain stem). Outcome was good in all nine patients after surgery for deep-seated brain cavernomas. There we also 13 cases of the brain stem cavernomas treated surgically. Of them, nine patients were stabilized or improved, one patient worsened, one patient died and two were lost to follow-up. Whatever the location, surgery should only concern symptomatic or hemorrhagic lesions close to the pia-matter or the ependyma as well as those covered by a thin layer of parenchyma. Neuronavigation and microsurgical procedures are essential in the treatment of deep-seated cavernomas.

Prediction of postoperative outcome with special respect to removal of hemosiderin fringe: A study in patients with cavernous haemangiomas associated with symptomatic epilepsy

PURPOSE

In this study 30 patients with symptomatic epilepsy caused by cavernomas were investigated in a postoperative follow up study to assess predictors for postoperative outcome with respect to indications, time and approach of surgery.

METHODS

Thirty patients with cavernomas refractory to medical treatment were scheduled for surgery based on the findings of high-resolution MR imaging and intensive EEG-video monitoring. Postoperative outcome of epilepsy was assessed by follow-up examinations based on the basis of classification by Engel and the International League against epilepsy (ILAE).

RESULTS

The following variables were associated with good postoperative outcome: (1) complete resection of hemosiderin fringe surrounding the cavernoma was correlated to less postoperative seizure frequency versus incomplete resection of the hemosiderin fringe according to the outcome protocol of ILAE. (2) Lower duration of epilepsy at the time of operation was correlated to a better postoperative outcome with a benefit for recovery. (3) Absence of hemorrhage before surgery and unifocal seizure onset was a predictor for a favorable outcome, whereas bilateral or multifocal seizure onset zones showed poorer postoperative outcomes. (4) In patients with dual pathology (hippocampal sclerosis in addition to a cavernoma), lesionectomy plus hippocampectomy as opposed to lesionectomy only, had a better outcome than single lesionectomy.

CONCLUSION

Postoperative outcome in patients with cavernomas should be the topic of further prospective multicenter studies involving a large number of patients. In addition to the ideal operation time and handling of dual pathology the role of extended resection including perilesional hemorrhages should be taken into account.

Neurosurgical management of cerebellar cavernous malformations

Object

The aim of this study was to analyze cerebellar cavernous malformations (CMs) with respect to epide-miological, clinical, radiological, and therapeutic aspects.

Methods

Between 1984 and 2004, 100 patients were surgically treated for intracranial CMs at the Division of Neurosurgery of Federal University of São Paulo. The authors reviewed the records of 10 patients whose lesions were located in the cerebellum.

There were four male and six female patients (ratio 1:1.5) whose ages ranged from 14 to 45 years (mean age 33 years). Clinical presentation was sudden or acute in all cases, and neuroimaging examinations performed in all patients demonstrated signs of bleeding. The mean size of the malformations was 4.6 cm, and in all but one patient the lesions were totally removed without complications. After a mean follow-up period of 70 months, all patients were considered to be in good or excellent clinical condition.

Conclusions

Cerebellar CMs should be analyzed separately from other posterior fossa CMs. These lesions can reach large sizes and cause massive hemorrhages, resulting in acute or sudden presentation. Surgery is a safe and effective option that provides a curative treatment when a complete removal is achieved.

Drug-resistant temporal lobe epilepsy due to cavernous malformations

Object

Supratentorial cavernous angiomas may be associated with drug-resistant focal epilepsy. Surgical removal of the malformation may result in seizure control in a number of patients, although in most studies a long history and high frequency of attacks have been recognized as indicators of unfavorable seizure outcome. In the literature, there are no clear indications regarding the optimal diagnostic presurgical workup and the surgical strategy for this particular subgroup of patients with symptomatic epilepsy. In this paper the authors focus on the preoperative workup and the surgical management of the disease in eight consecutive patients undergoing surgery for drug-resistant temporal lobe epilepsy (TLE) due to cavernous malformations (CMs), and the relevant literature on this issue is also reviewed.

Methods

Preoperatively, all patients were assessed using a noninvasive protocol aimed at localizing the epileptogenic zone on the basis of anatomical, electrical, and clinical criteria. The presurgical assessment yielded an indication for lesionectomy in two cases, lesionectomy plus anteromesial temporal lobectomy in four cases, and lesionectomy plus extended temporal lobectomy in two cases. At follow-up examinations, seizure, neuropsychological, and psychiatric outcomes were all evaluated. Seven patients were categorized in Engel Class IA (seizure free), and one was categorized in Engel Class IB (occasional auras only). No adverse effects on neuropsychological or psychosocial functioning were observed.

Conclusions

Epilepsy surgery can be performed with excellent results in patients with intractable TLE caused by CMs. Noninvasive presurgical evaluation of these patients may enable a tailored approach, providing complete seizure relief in most cases.

Cavernous Angioma of the Cerebellopontine Angle

Although cavernous hemangiomas are commonly found supratentorially, their presence in the internal auditory canal is uncommon. We describe a case that was initially mistaken for a vestibular schwannoma due to its location in the cerebellopontine angle. Although there can be overlap in their presentations, familiarity with the characteristic magnetic resonance imaging findings of both entities will aid in their differentiation and potentially affect preoperative planning.

Intracranial cavernous angioma: a practical review of clinical and biological aspects

BACKGROUND

Cavernomas are an uncommon lesion seen in neurosurgical practice that can occasionally rupture. Recent developments in neurosurgical technique and microbiology have brought greater insight into the treatment and molecular pathogenesis of cavernoma. In this review, a historical overview of cavernous angioma, a current paradigm for treatment, promising new molecular biological developments, and suggestions for future directions in neurosurgical research are presented, with emphasis on practical clinical applications.

METHODS

A survey of the literature on cavernous angioma and consultation with the Department of Neurosurgery at Northwestern Memorial Hospital was conducted by the authors to gain greater insight regarding this lesion. Papers and consultation revealed the importance of careful evaluation of this lesion, new techniques such as functional magnetic resonance imaging and frameless stereotaxy that simplify clinical management of cavernomas, and potential mechanisms by which to tackle this lesion in the future. New basic knowledge on disease biology is summarized with practical applications in the clinical arena.

RESULTS

There appear to be a number of controversies regarding management of this lesion. These include risk factors faced by the patient, controversy over the importance of resection, and modality through which the treatment should occur. An algorithm is presented to aid the neurosurgeon in management of these lesions.

CONCLUSIONS

Exciting developments in neurosurgery and molecular biology will continue to have a major impact on clinical treatment of this disease. Unresolved issues regarding the importance of certain risk factors, the role for radiotherapy in treatments, and the underlying molecular abnormalities must be tackled to gain greater clarity in treatment of this lesion.

[Cavernous haemangiomas: hearing and vestibular inaugural symptoms]

INTRODUCTION

Cavernous haemangiomas (cavernomas)(CH) are relatively rare (2% of cranial tumoral pathology) vascular malformations mostly observed in the central nervous system. Their most common topographical site in brain stem is midline in the pons, for which clinical course may mimic symptoms of peripheral origin (sudden deafness, fluctuating hearing loss, Meniere-like vertigo).

AIM

To establish the correlation between the clinical manifestations of hearing and balance disturbance and the anatomical site within the pons of cavernous haemangiomas, and to describe their clinical features, and the findings on auditory brainstem response (ABR) and magnetic resonance imaging (MRI). To propose a literature review about CH and its implications.

MATERIAL AND METHOD

We made a retrospective review of the histories of three patients aged 24, 44 and 45 years, diagnosed as having cavernomas of the brainstem in which audiometric evaluation, videonystagmography (VNG), ABR and imaging techniques lead to the diagnosis of intracranial cavernoma.

RESULTS

The clinical and radiological files were reviewed and a direct relationship between symptoms and localization was found in all 3 patients, especially in relation to our understanding of the auditory and vestibular pathways within the brainstem.

CONCLUSION

The literature regarding cavernomas of the pons is reviewed and the clinical, neuroimage, pathological, natural course and management aspects of the disease are discussed. We recommend the use of cerebral MRI for initial diagnosis which shows a typical rosette-like appearance with a heterogeneous signal on T2-weighted images, along with follow-up and investigation into similar profiles among family members. At present there is no consensus about the treatment to follow when cavernomas are located in the brain stem. There is no specific medical treatment for this condition, and surgery is indicated only exceptionally. Anticoagulant therapy, platelet-dispersing medication and violent sports activities are contraindicated.

[Cavernous malformations: surgical management in Belo Horizonte Santa Casa Hospital]

The better understanding of the natural history of the cavernous malformations and the improvement of diagnostic methods and of microsurgical techniques have made the management of cavernous malformations possible through the conservative treatment, radiosurgery, and microsurgical resection. We present 33 cases operated at our service at Santa Casa Hospital, Belo Horizonte, from 1992 to 2001. Cortical and subcortical cavernomas manifested by epilepsy (57.5%) or mainly by hemorrhage (15.1%) were surgically approached. The deep lesions (basal ganglia, thalamus and brain steam) represented 27.7% of our cases. They should only be operated when located near the pial or ependimary surface. The resection of spinal cord lesions (5.5%) and of deep brain lesions is also recommended when they present progressive focal deficit (13.8%) or recurrent episodes of hemorrhage (13.8%). Small and deep seated cavernomas that do not present bleeding must be conservatively treated. There has been no evident favourable result related to radiosurgery so far.

[Supratentorial cavernoma and epileptic seizures. Are there predictors for postoperative seizure control?]

For cavernous haemangiomas, it is the aim of surgical treatment to control epilepsy and eliminate potential sources of intracerebral haematomas. In the following investigation, it was attempted to find indicators for seizure freedom after surgery. Success of therapy was assessed according to three patterns of classification. Thirty patients underwent tailored resection based on findings from preoperative investigations and intraoperative electrocorticography. Follow-up averaged 4 years. Lesionectomy, extended lesionectomy, and modified lobe resection were carried out in 13, 11, and six patients, respectively. For all procedures, including microsurgical lesionectomy, the firm gliotic layer unequivocally differed in colour and consistency from normal brain and was removed. Further tissue resection was carried out only if the electrocortical course suggested persistent spike activity around the resection cavity or if presurgical MRI evaluation (e.g. hippocampal atrophy) or electrophysiology also pointed to pathology distant from the lesion. Of the patients, 53.3% became completely seizure-free (Engel I), and one additional patient had only occasional isolated auras. Dramatic reductions in seizure frequency and severity were exhibited by 26.7%. Outcome in respect to seizure control was not associated with resection procedure, comparing pure lesionectomy with lesionectomy plus cortectomy. In the group of patients with epilepsy surgery, those with hippocampectomy had significantly better outcome than those without. Important prognostic factors were early operation after seizure manifestation (91.7% operated upon within 2 years of seizure onset became seizure-free). Another prognostic factor was unifocal seizure onset (bilateral or multifocal seizure onset was found in care of the ten patients with unfavourable outcome). None of the four patients harbouring multiple cavernomas became seizure-free after resection of one lesion, which was believed to be mostly attributable to the epileptic focus that was removed.

Cavernous haemangiomas, epilepsy and treatment strategies

BACKGROUND

Cavernous haemangiomas (cavernomas) are benign vascular malformations which can be found at any region within the central nervous system. Epilepsy is the most frequent manifestation of this malformation. Magnetic resonance imaging (MRI) used for the diagnostic evaluation of symptomatic seizures is a sensitive and specific method for the detection of cavernomas. Due to an increased application of MR imaging in the diagnostic evaluation of symptomatic seizures cavernomas have been found with increasing frequency over the past years. To achieve optimal treatment of patients with cavernous haemangiomas and epilepsy both medical and surgical treatment have to be considered.

OBJECTIVE

This paper reviews published studies and presents our own results concerning current treatment schedules of epileptogenic cavernomas.

RESULTS

In patients with intractable epilpesies surgical treatment of cavernomas seems to be the most successful antiepileptic therapy. Whether microsurgical lesionectomy, including the removal of only the cavernoma, or a more extensive resection is needed to achieve this aim are discussed.

CONCLUSION

New data acquired with high-resolution imaging (MRI, PET) and electrophysiology indicate that magnetencephalography (MEG) may contribute to the delineation of epileptogenic tissue bordering the lesion, thus permitting appropriate inclusion of this specific area within the resection, instead of performing a simple lesionectomy.

Image-guided Transsylvian, Transinsular Approach for Insular Cavernous Angiomas

OBJECTIVE

Surgical treatment of cavernomas arising in the insula is especially challenging because of the proximity to the internal capsule and lenticulostriate arteries. We present our technique of image guidance for operations on insular cavernomas and assess its clinical usefulness.

METHODS

Between 1997 and 2003, with the guidance of a frameless stereotactic system (BrainLab AG, Munich, Germany), we operated on eight patients who harbored an insular cavernoma. Neuronavigation was used for 1) accurate planning of the craniotomy, 2) identification of the distal sylvian fissure, and, finally, 3) finding the exact site for insular corticotomy. Postoperative clinical and neuroradiological evaluations were performed in each patient.

RESULTS

The navigation system worked properly in all eight neurosurgical patients. Exact planning of the approach and determination of the ideal trajectory of dissection toward the cavernoma was possible in every patient. All cavernomas were readily identified and completely removed by use of microsurgical techniques. No surgical complications occurred, and the postoperative course was uneventful in all patients.

CONCLUSION

Image guidance during surgery for insular cavernomas provides high accuracy for lesion targeting and permits excellent anatomic orientation. Accordingly, safe exposure can be obtained because of a tailored dissection of the sylvian fissure and minimal insular corticotomy.

Intracranial cavernous malformations

Cavernous malformations are commonly being recognized on CT and MR imaging in both asymptomatic and symptomatic patients. The diagnosis of CMs can often be made on MR imaging based on the characteristic morphology of the subacute and chronic blood products. An atypical appearance of a CM in the setting of a recent hemorrhage requires follow-up imaging to confirm the diagnosis. Deep CMs have a significant clinical event rate that justifies close follow up or surgical treatment if possible.

Intracerebral hemorrhage secondary to vascular lesions

The article reviews intracerebral hemorrhage caused by vascular malformations. The article also reviews incidence, prevalence, and distribution of parenchymal hemorrhage caused by aneurysms, arteriovenous malformations, and cavernous malformations are defined, and less common vascular lesions. There is a discussion of the role of cerebral vascular malformations in producing cerebral hemorrhage in young adults abusing illicit drugs.

Multiple cavernomas of brain presenting with simultaneous hemorrhage in two lesions: a case report

BACKGROUND

Cavernomas are rare vascular lesions of the brain that can bleed. However, the risk of bleeding is lower than that of aneurysms or arteriovenous malformations. In selected cases, bleeding cavernomas require surgical management. Presented here is a case of multiple cavernomas of the brain with simultaneous bleeding in two different lesions, along with its management. Although multiple cavernomas have been described in the literature, simultaneous bleeding in two different lesions is rare.

CASE DESCRIPTION

A 52-year-old woman presented with difficulty maintaining balance, double vision, and slurred speech. She had had multiple surgeries for cavernous angioma of the brain in the past. Examination and investigations revealed two cavernomas, one in the dorsal midbrain region and one in the left occipital region. Her clinical condition deteriorated suddenly, and further evaluation revealed bleeding in both the cavernomas. The lesion in the midbrain was removed surgically. Since the lesion was in the posterior midbrain, a posterior interhemispheric approach was used with the help of frameless stereotactic navigation. Total excision was achieved. The lesion in the occipital lobe was not operated on. The patient had an uneventful recovery. It was planned to observe the progress of the occipital cavernoma by serial magnetic resonance imaging scans.

CONCLUSION

Although there may be simultaneous bleeding in two or even more lesions, surgical treatment should be undertaken for the lesions jeopardizing critical structures or exerting mass effects. Additionally, it was discovered that frameless stereotactic navigation was of immense help in delineating the lesion and for safe excision of the lesion in critical areas.

Surgical treatment for intractable epilepsy caused by cavernous angioma in the temporal lobe of the dominant hemisphere--three case reports

The surgical treatment modality for intractable epilepsy with cavernous angioma in the dominant hemisphere is still unclear. Three patients with medically intractable seizures associated with cavernous angioma in the dominant hemispheric temporal lobe underwent tailored resection based on magnetic resonance (MR) imaging, single photon emission computed tomography (SPECT), electroencephalography monitoring (from scalp and sphenoidal electrodes), and neuropsychologic assessment. Epileptogenic zones were located in the area surrounding the angioma in all patients and mesial temporal dysfunction in two patients. The adjacent cortex and gliotic tissues containing hemosiderin were resected, in conjunction with either total or partial resection of the nidus. Intraoperative electrocorticography (ECoG) was then performed. Additional resection of the mesial temporal structures or multiple subpial transection was performed as indicated by the ECoG findings. All three patients have been seizure free and showed no language or cognitive deterioration for 30, 18, and 14 postoperative months, respectively, while receiving tapered antiepileptic medication. Tailored resection based on electrophysiological data, MR imaging, SPECT, and intraoperative ECoG is effective for the treatment of medically intractable seizure associated with cavernous angioma in the temporal lobe of the dominant hemisphere.

Pineal region cavernoma--case report

A 45-year-old male presented with a rare pineal region cavernoma. Magnetic resonance (MR) imaging confirmed the preoperative diagnosis. The tumor was totally excised. The patient was subsequently cured. Analysis of 15 reported cases found a slight female preponderance. The second and third decades were the most common age group. The course of pineal cavernomas can be complicated by hemorrhage, occlusion of cerebrospinal fluid pathways, and focal neurological and neuroendocrine symptoms but no specific clinical features. However, MR imaging has high sensitivity and the specificity for the diagnosis of pineal cavernoma. Total microneurosurgical excision is the treatment of choice, and patients had an excellent outcome. Stereotactic biopsy can be potentially dangerous because of the risk of hemorrhage. The use of radiosurgery requires evaluation of long-term risks and safe dose levels. Total excision of the pineal cavernoma using microsurgical techniques is the choice of treatment in young and healthy patients since there is an increased risk of recurrent hemorrhage and progressive neurological decline. A conservative approach is preferred in older patients.

Persistent hiccup as presenting symptom in medulla oblongata cavernoma: a case report and review of the literature

A rare case of persistent intractable hiccup as presenting symptom of cavernous angioma in the medulla oblongata is reported. Pathophysiologic hypotheses about the triggering mechanism of hiccup are discussed, with special reference to the causes affecting the central nervous system. A review of the literature concerning medullary lesions presenting with persistent hiccup is also reported. Finally we have included some brief considerations about cavernous angiomas and the patterns of their clinical presentation, focusing on those located in the medulla oblongata.

Thalamic cavernous malformations

BACKGROUND

Only few anecdotal reports and small series of thalamic cavernous malformations have been reported. It follows that the clinical behavior and management are poorly understood; in particular, experiences with the surgical treatment of these lesions are scarce.

METHODS

The clinical course, treatment, and outcome of 12 patients (10 females and 2 males, mean age 36 years) with symptomatic cavernous malformations of the thalamus are reviewed. Eight patients (66%) presented with cerebral hemorrhage, one with progressive neurological deficit and three with hydrocephalus/increased intracranial pressure; associated venous anomalies were found in three cases. Treatment consisted of radical surgery in four cases with progressive neurological decline or recurrent disabling hemorrhage, radiosurgery (one case), evacuation of a chronic satellite hematoma (one case), ventriculoperitoneal shunt for hydrocephalus (one case) and observation (five cases). Operative treatment in four cases included transcallosal, trigonal, and occipital interhemispheric approaches.

RESULTS

In the surgical group, one patient died, two improved after operation, and one remained the same. Of the patients not operated on radically, one had recurrent hemorrhage 4 months after radiosurgery, one remains stable 8 years after ventriculoperitoneal shunt, and one 3 years after aspiration of a satellite hematoma. Five other patients presenting with thalamic hemorrhage were treated conservatively; recurrent hemorrhage occurred in two cases at 1 month and at 2 years, leaving a mild residual deficit in both cases. Overall, rehemorrhage occurred in four cases (50%) at a mean interval of 18 months after the first bleeding; the annual hemorrhage rate was 6.1%.

CONCLUSIONS

Thalamic malformations are more likely to be symptomatic from small hemorrhages compared with lesions in the cerebral hemispheres; progressive growth may also occur with third ventricle invasion or caudal extension to the midbrain. Their high-risk location deters heavy-handed management, but they should not be left long untreated. Both surgery and radiosurgery have been used in the management of thalamic cavernomas reported in the literature. Definite surgical indications include progressive neurological decline and recurrent hemorrhages of malformations abutting the ventricular surface or the posterior incisural space; the complex anatomy of the deep venous system and the association with unexpected venous anomalies complicates the removal of these lesions.

Cavernous angiomas of the brain stem. Intra-axial anatomical pitfalls and surgical strategies

BACKGROUND

We review the surgical anatomy of the brain stem in relation to the surgical approaches adopted for treatment of cavernomas and identify possible "safe entry zones" on the anterior face of the brainstem.

METHODS

Twelve symptomatic patients with cavernoma or telangectasia of the brain stem were surgically treated. The brain stem was divided into the following anatomical areas: ventral medulla, dorsal medulla, dorsal pons, ventral pons, ventral mesencephalon, and dorsal mesencephalon, so that the surgical approach could be "individualized" according to the position of the cavernoma, the nerve fasciculi and nuclei.

RESULTS

On the anterior surface of the brain stem a medullar paramedian oblique access to the anterolateral sulcus and a paramedian sagittal pons access seem to avoid the main nerve fasciculi and nuclei.

CONCLUSIONS

Although the parenchymal window produced by the cavernoma is the most important parameter for the choice of approach, fairly safe entry zones may be identified even on the anterior surface of the medulla and pons.

Supratentorial cavernous haemangiomas and epilepsy: a review of the literature and case series

OBJECTIVES

To characterise the clinical features and response to treatment of supratentorial cavernomas associated with epilepsy.

METHODS

A systematic review of the literature was carried out and a retrospective case series of patients with cavernoma diagnosed by MRI and/or histology was compiled. Patient selection biases in the literature review were reduced as far as possible by selection of unbiased publications.

RESULTS

In the literature, cavernomas were relatively less common in the frontal lobes. There were multiple cavernomas in 23% of cases. The main clinical manifestations were seizures (79%) and haemorrhage (16%). The annual haemorrhage rate was 0.7%. The outcome after excision was good with improvement in seizures in 92% of patients. In the case series the surgical outcome was less favourable, reflecting inclusion of a higher proportion of patients with intractable epilepsy. In both the literature review and the case series, outcome was poorer in cases with a longer duration of seizures at the time of surgery.

CONCLUSIONS

The good surgical results, particularly in cases treated earlier, and the significant cumulative haemorrhage rate, suggest that excision is the optimum treatment. However, these factors have not been examined prospectively and, despite the availability of several retrospective studies, the optimum treatment, particularly for non-intractable cases, will only be determined by a prospective study.

Intramedullary cavernous angioma. Resection by oblique corpectomy

BACKGROUND

Intramedullary cavernomas are rare lesions usually operated on via a posterior approach and myelotomy.

CASE REPORT

A 42-year-old woman progressively developed a tetraplegia with sphincter disturbances over a period of 26 years. Magnetic resonance imaging showed a cervical intramedullary cavernoma with an extramedullary anterolateral exophytic portion. To avoid myelotomy, this lesion was approached directly via its anterior exophytic portion. Through a cervical anterolateral approach, the vertebral body of C4 and the intervertebral discs were obliquely drilled out. The posterior longitudinal ligament and the dura mater were opened. The exophytic portion was coagulated and the intramedullary portion was completely excised. The dura mater was closed and a bone graft was inserted between C3 and C5 and secured with a plate.

RESULTS

After transient worsening, upper limb weakness improved from its preoperative status but paraparesis persisted after a follow-up of 12 months. The sphincter disturbances disappeared.

CONCLUSIONS

The anterolateral approach combined with oblique corpectomy may be an appropriate technique in case of anterior intramedullary cavernomas. It provides direct access to the lesion, avoiding additional myelotomy.

Ossified and de novo cavernous malformations in the same patient

We report the case of a 44-year-old patient with a MRI scan showing a newly developed cavernoma after two highly calcified lesions had been excised surgically. Six other cavernous malformations had been followed by MR imaging over a 2-year period. The coexistence of the two extremes of cavernous malformations in terms of lesions development--de novo and ossified lesions has not been reported previously and has implications for both the follow-up and the natural history of these malformations. The potential for developing new cavernous malformations persists and does not seem to be related to the evolutional stage of pre-existing lesions. It is suggested that these patients need to be followed up by MRI on a regular basis.

Surgical outcome in patients with epilepsy with occult vascular malformations treated with lesionectomy

PURPOSE

This retrospective study reports the long-term surgical outcome of patients with medically refractory epilepsy and vascular malformations who were treated with lesionectomy. A detailed analysis of surgical failures had been performed in an attempt to define predictors of surgical success and failure.

METHODS

Fifteen patients with medically intractable epilepsy and angiographically occult vascular malformations (AOVMs) were treated surgically with lesionectomy at Duke University Medical Center. Lesionectomy consisted of removal of the AOVM and surrounding hemosiderin-stained brain only, without the use of electrocorticography (ECoG) to guide resection.

RESULTS

Eleven (73%) patients are seizure free after lesionectomy. Three showed no significant improvement, and one patient died, presumably after a seizure. Age of onset, duration of seizures, age at resection, and gender did not affect outcome. All patients with neocortical AOVMs in whom EEG findings correlated with the site of the lesion were seizure free after lesional resection. Treatment failures were associated with the presence of multiple intracranial lesions, poorly localized or diffuse EEG findings, discordant positron emission tomography (PET) imaging, or with a lesion in close proximity to the limbic system.

CONCLUSIONS

Lesionectomy, with removal of surrounding hemosiderin-stained brain, can be considered the procedure of choice in carefully selected patients with epilepsy with occult vascular malformations.

Early radiologically proven rebleeding from intracranial cavernous angiomas: report of 6 cases and review of the literature

Although intracranial cavernomas are known to cause haemorrhage, data concerning the frequency, severity and delay of recurrent bleedings are controversial. We report a series of 6 patients with histologically proven cavernoma, presenting with early clinical signs and radiological proof of rebleeding, that is occurring in the first month after initial overt haemorrhage. These 6 cases have been selected from a series of 142 patients seen between 1980 and 1995 in our department with cavernous angiomas or so-called AOVMs, of whom 93 presented with clinical symptoms of haemorrhage (34 patients presented symptoms of one or more rebleeding, but only 6 had radiological proof). All patients suffered neurological worsening due to the rebleeding, with an increase of the size of the haematoma on the CT scan. Five MRIs were performed at the acute stage: 3 showed evidence of cavernoma (60%). All patients underwent surgery at the acute stage of the rebleeding, with 5 improvements and 1 stabilization. A cavernous angioma was found in 5 cases at first surgery, but a further operation was necessary in the last patient to find and remove the cavernoma, after a second rebleeding following the first intervention. Our series reveals a high frequency of rebleeding after a first intracranial haemorrhage from a cavernous angioma, and highlights the precocity of such rebleedings. Therefore, we advocate early aggressive surgical management: in cases of cavernoma revealed by a first clinical overt haemorrhage, when there is strong radiological suspicion at the acute stage; and in all cases of rebleeding, even without radiological evidence of malformation, in the absence of vascular risk factors. Surgical indication must be discussed in particular cases of cavernomas of the brain stem when neither the haematoma nor the cavernoma reach the surface, and in deep supratentorial cavernomas, when the neurological status is good, because of the therapeutic risk.

Supratentorial cavernous malformations and epilepsy: seizure outcome after lesionectomy on a series of 35 patients

Epilepsy is the most frequent presenting sign in patients with cavernous angiomas and is the major cause of morbility. Persistence of seizures after surgical treatment prompted many authors to examine the possibility of removing the cavernoma and the surrounding tissue. In our series of 53 cavernous angiomas, all the 35 patients with preoperative seizures underwent surgery by means of lesionectomy alone. One hundred percent of patients with less than five preoperative seizures and/or an history under 12 months was seizure free, while only 62.5% of patients with more than five seizures and/or an history longer than 12 months was seizure free. Number and duration of seizures before surgery seems to be the most important factor in the seizure outcome after surgical treatment.

Surgical management of brain-stem cavernomas

We present a series of seven patients who were operated on for symptomatic brain-stem cavernomas. The following approaches were used: medial suboccipital (N = 4), lateral suboccipital (N = 1), subtemporal-transtentorial (N = 1), and frontal transcortical-transventricular-subchorioidal-trans velum interpositum (N = 1). Intraoperative motor (N = 4) and somatosensory (N = 1) evoked potential monitoring revealed temporary changes in 3 patients. Immediately postoperatively, the following additional deficits were observed in 6 patients: oculomotor nerve paresis (N = 2), abducens nerve paresis (N = 3), facial nerve paresis (N = 2), deafness (N = 1), and increased ataxia (N = 3). One patient died due to septic complications not related to surgery. After a mean observation time of 2 years, 2 patients had improved, 3 were unchanged, and 1 patient deteriorated as compared to his preoperative status. In conclusion, surgical treatment of brain-stem cavernomas, although carrying a significant risk of temporary neurological deterioration is recommended in symptomatic patients in whom the cavernoma seems to reach the surface of the brain-stem. Intraoperative functional topographic mapping and monitoring have proven useful tools lowering the surgical risks in these patients.

Familial cavernous hemangioma with atypical neuroimaging

Three members of the same family were studied, all of whom had multiple intracerebral cavernous angiomas for which a dominant autosomal inheritance was hypothesised. The proband suffered from headaches, and physical examination revealed evident right hemiparesis. The second case started with a hemorrhagic cerebral stroke and the third was asymptomatic on neurological examination. Nuclear magnetic resonance (NMR), performed in two of the three cases, showed lesions whose number and extent were not radiologically characteristic of cavernous angioma. A cerebral biopsy of the proband enabled the diagnosis to be made. Despite the recent introduction of NMR, the nosological classification of familial forms can be difficult when the radiological lesions are atypical. In such cases, cerebral biopsy is not only a valid diagnostic aid, but is also indispensable for obtaining adequate genetic information.

Supratentorial cavernous angiomas and epileptic seizures: preoperative course and postoperative outcome

OBJECTIVE

Patients operated on for supratentorial cavernous angiomas were studied to define the incidence and the course of seizures in their clinical history. Electroclinical and neuroradiological data were correlated with the location of cavernomas. The impact of lesionectomy on the outcome of seizures was evaluated.

METHODS

Preoperative clinical data on the history of the seizures, semeiology, incidence, severity, and response to antiepileptic drugs were analyzed. The location of the cavernomas, revealed by magnetic resonance imaging, was correlated with electroencephalographic and clinical data. Postoperative clinical and neuroradiological data were evaluated, with particular consideration to the outcome of the seizures, antiepileptic drug withdrawal, and the completeness of the lesion excision.

RESULTS

A higher incidence of severe epilepsy was observed in the patients with mesiotemporal and cortical angiomas. In most of the patients (78.7%), a good concordance between the site of the lesion and the electroclinical data was found. The complete removal of the lesion led to a favorable outcome, with discontinuation of antiepileptic drugs achieved in one-quarter of the patients.

CONCLUSION

A high percentage of patients with cortical cavernomas had epileptic seizures. They often presented with chronic intractable epilepsy (44.7% in our series). In cases of good concordance between the electroclinical data and the location of the angioma, complete lesionectomy led to the disappearance of seizures. Removal of the hemosiderin ring did not correlate with better outcome. Preoperative ictal scalp recordings to assess the topographic relationship between the cavernoma and the epileptic seizures could improve outcome, which suggests different surgical strategies (lesionectomy versus enlarged resection) in patients without a clear-cut concordance between the site of the lesion and the ictal semeiology.

Seizure control following surgery in supratentorial cavernous malformations: a retrospective study in 77 patients

Of 168 patients operated on consecutively for a supratentorial cavernous malformation, 77 had seizures as the initial symptom. The effectiveness of surgery in controlling seizures and the risk of surgery were evaluated by retrospective review of the patients' charts. The follow-up period was 1 to 9 years (mean 39 months) and the review period totalled 284 lesion-years. Only two patients showed postoperative deterioration in neurological status (morbidity risk: 2.6%), no patient died (mortality: 0%). Sixty-eight (88.3%) patients were seizure-free after operation and five (6.5%) showed a marked reduction in the frequency of their seizures. This corresponds to an overall positive effect of surgery of 94.8% of the patients. There was no substantial evidence that excision of the haemosiderin-stained tissue around the cavernoma along with the lesion itself provided better results than resection of only the cavernoma. Better results with regard to seizure control, however, were associated with shorter duration of symptoms before surgery.

Extracerebral cavernous angiomas of the cavernous sinus in the middle fossa

Intracranial extracerebral cavernous angiomas (ECCAs) share the same histologic features as intracerebral lesions, but their clinical picture is different. Surgical treatment of ECCAs of the cavernous sinus remains a challenge for the neurosurgeon because of a high mortality and morbidity due to uncontrollable and massive hemorrhage.

METHODS

We have experienced seven patients with ECCAs of the cavernous sinus between 1982 and 1994. All cases were verified histologically during surgery and two were totally resected during the first surgical attempt. Six of seven patients were female. The mean age at diagnosis was 54.5 years (range; 43 to 71 years).

RESULTS

Computed tomography showed a round or dumbbell-shaped mass in the area of the cavernous sinus. Magnetic resonance imaging revealed a low to isointense mass lesion on the T1-weighted image. Only one of our patients showed a minimal amount of vascular staining on angiography. The total excision of these malformations was difficult because intraoperative bleeding could be profuse. In one case, radiation therapy induced a reduction in the size of the tumor after failure of surgical removal.

CONCLUSIONS

In planning surgical strategy for ECCAs, care should be taken to control the massive bleeding. Radiation therapy is helpful to suppress the tumor growth.

Reduction of hemorrhage risk after stereotactic radiosurgery for cavernous malformations

The benefits of radiosurgery for cavernous malformations are difficult to assess because of the unclear natural history of this vascular lesion, the inability to image malformation vessels, and the lack of an imaging technique that defines "cure." The authors selected for radiosurgery 47 patients who harbored a hemorrhagic malformation in a critical intraparenchymal location remote from a pial or ependymal surface. Of these, 44 patients had experienced at least two hemorrhages before radiosurgery. The mean patient age was 39 years; six patients had previously undergone attempted surgical removal. The malformation was located in the pons/midbrain in 24 cases, the medulla in three, the thalamus in nine, the basal ganglia in three, deep in a parietal lobe in four, and deep in a temporal lobe in four. Patients had sustained initial hemorrhages from 0.5 to 12 years prior to radiosurgery (mean 4.12 years). In these patients, who were not typical of the majority of patients with cavernous malformations, there were 109 bleeds before radiosurgery in 193 prior observation-years, for 56.5% annual hemorrhage rate (including the first hemorrhage), or an annual rate of 32% subsequent to the first hemorrhage. The mean follow-up period after radiosurgery was 3.6 years (range 0.33-6.4 years). The proportion of patients with hemorrhage after radiosurgery was significantly reduced (p < 0.0001), as was the mean number of hemorrhages per patient (p = 0.00004). In the first 2 years after radiosurgery, there were seven bleeds in 80 observation-years (8.8% annual hemorrhage rate). In the 2- to 6-year interval after radiosurgery, the annual rate decreased to 1.1% (one bleed). After radiosurgery, 12 patients (26%) sustained neurological worsening that correlated with imaging changes. In eight patients these deficits were temporary; two underwent surgical resection and died. Two patients had new permanent deficits (4%). A significant reduction was observed in the hemorrhage rate after radiosurgery in patients who had deep hemorrhagic cavernous malformations, especially after a 2-year latency interval. This evidence provides further support to the belief that radiosurgery is an effective strategy for cavernous malformations, especially when located within the parenchyma of the brainstem or diencephalon.