Combined MRI and PET imaging in brain stem mass lesions: diagnostic yield in a series of 30 stereotactically biopsied patients

Full access

Object. In the management of brainstem lesions, the place of stereotactic biopsy sampling remains debatable. The authors compared the results of magnetic resonance (MR) imaging, positron emission tomography (PET) scanning, and histological studies obtained in 30 patients who underwent MR imaging— and PET-guided stereotactic biopsy procedures for a brainstem mass lesion.

Methods. Between July 1991 and December 1998, 30 patients harboring brainstem mass lesions underwent a stereotactic procedure in which combined MR imaging and PET scanning guidance were used. Positron emission tomography scanning was performed using [18F]fluorodeoxyglucose in 16 patients, methionine in two patients, and both tracers in 12 patients. Definite diagnosis was established on histological examination of the biopsy samples. Interpretation of MR imaging findings only or PET findings only was in agreement with the histological diagnosis in 63% and 73% of cases, respectively. Magnetic resonance imaging and PET findings were concordant in 19 of the 30 cases; in those cases, imaging data correlated with histological findings in 79%. Treatment based on information derived from MR imaging was concordant with therapy based on histological findings in only 17 patients (57%). Combining MR imaging and PET scanning data, the concordance between the neuroimaging-based treatment and treatments based on histological findings increased to 19 patients (63%). In seven patients who underwent biopsy procedures with one PET-defined and one MR imaging—defined trajectory, at histological examination the PET-guided samples were more representative of the tumor's nature and grade than the MR imaging—guided samples in four cases (57%). In 18 patients PET scanning was used to define a biopsy target and provided a diagnostic yield in 100% of the cases.

Conclusions. Although the use of combined PET and MR imaging improves radiological interpretation of a mass lesion in the brainstem, it does not accurately replace histological diagnosis that is provided by a stereotactically obtained biopsy sample. Combining information provided by MR imaging and PET scanning in stereotactic conditions improves the accuracy of targeting and the diagnostic yield of the biopsy sample; an MR imaging— and PET-guided stereotactic biopsy procedure is a safe and efficient modality for the management of mass lesions of the brainstem.

Abstract

Object. In the management of brainstem lesions, the place of stereotactic biopsy sampling remains debatable. The authors compared the results of magnetic resonance (MR) imaging, positron emission tomography (PET) scanning, and histological studies obtained in 30 patients who underwent MR imaging— and PET-guided stereotactic biopsy procedures for a brainstem mass lesion.

Methods. Between July 1991 and December 1998, 30 patients harboring brainstem mass lesions underwent a stereotactic procedure in which combined MR imaging and PET scanning guidance were used. Positron emission tomography scanning was performed using [18F]fluorodeoxyglucose in 16 patients, methionine in two patients, and both tracers in 12 patients. Definite diagnosis was established on histological examination of the biopsy samples. Interpretation of MR imaging findings only or PET findings only was in agreement with the histological diagnosis in 63% and 73% of cases, respectively. Magnetic resonance imaging and PET findings were concordant in 19 of the 30 cases; in those cases, imaging data correlated with histological findings in 79%. Treatment based on information derived from MR imaging was concordant with therapy based on histological findings in only 17 patients (57%). Combining MR imaging and PET scanning data, the concordance between the neuroimaging-based treatment and treatments based on histological findings increased to 19 patients (63%). In seven patients who underwent biopsy procedures with one PET-defined and one MR imaging—defined trajectory, at histological examination the PET-guided samples were more representative of the tumor's nature and grade than the MR imaging—guided samples in four cases (57%). In 18 patients PET scanning was used to define a biopsy target and provided a diagnostic yield in 100% of the cases.

Conclusions. Although the use of combined PET and MR imaging improves radiological interpretation of a mass lesion in the brainstem, it does not accurately replace histological diagnosis that is provided by a stereotactically obtained biopsy sample. Combining information provided by MR imaging and PET scanning in stereotactic conditions improves the accuracy of targeting and the diagnostic yield of the biopsy sample; an MR imaging— and PET-guided stereotactic biopsy procedure is a safe and efficient modality for the management of mass lesions of the brainstem.

The management of brainstem mass lesions remains controversial; particularly when the lesion cannot be removed and is of an infiltrating nature, the benefit of a stereotactic procedure is still debatable.2,16,17,23,25 One objection to performing a brainstem stereotactic biopsy procedure is that it may not be reliable because the tumor may be heterogeneous.13,26 Moreover, this heterogeneity often necessitates multiple sampling, which may be dangerous in the brainstem. Some authors also contend that obtaining a histological diagnosis of brainstem tumors by a biopsy procedure is not necessary in most cases because of the effectiveness of modern cerebral imaging modalities, especially MR imaging.2,23 In that respect, PET scanning may also be of interest, because this imaging method provides independent metabolic information that may be helpful in determining the nature and aggressiveness of brain tumors.11,13 However, according to some authors, obtaining a stereotactic biopsy sample of brainstem mass lesions remains the best diagnostic procedure because a presumptive diagnosis based on MR imaging findings alone may lead to inaccurate diagnosis and, more importantly, erroneous treatment.4

In several recent studies we and other investigators have encouraged the use of PET scanning during stereotactic brain biopsy procedures to increase reliability of sampling by optimizing target selection.19,21 Since 1991, we have routinely incorporated PET in our planning of stereotactic biopsy sampling of cerebral tumors. To determine the additional value of PET we evaluated the use of combined PET/MR imaging in 30 patients in whom stereotactic biopsy samples of a brainstem lesion were obtained.

Clinical Material and Methods

Between July 1991 and December 1998, 30 patients with a brainstem mass lesion underwent a stereotactic procedure in which combined PET/MR imaging guidance was used. Patient age varied between 4 and 78 years (median 43 years); four patients were younger than 18 years of age (Table 1). The male/female ratio was 14:16. Symptoms consisted of walking disturbances in 22, visual impairment in 13, signs of intracranial hypertension (headache, nausea, and drowsiness) in 11, dysphagia or dysarthria in eight, and hemiparesis in six. The lesion was centered on the midbrain in 12 patients, the pons in 14, and the medulla in four patients; associated obstructive hydrocephalus was present in five patients (two children and three adults) and was treated by ventriculostomy or placement of a ventriculoperitoneal shunt in three and two cases, respectively. The PET-guided biopsy procedures were performed in accordance with the ethical guidelines of our institution.

TABLE 1

Location of the lesion and imaging and histological data obtained in 30 patients*

Imaging-Defined Diagnosis
Case No.Age (yrs), SexLocationMR ImagingFDG-PETMet-PETHistological DiagnosisTreatment
111, Fponslow-grade gliomaLMglioblastomaradio- & chemotherapy
214, MmidbrainpineoblastomaHMHMgangliocytomanone
3 4, Fponslow-grade gliomaHMglioblastomaradio- & chemotherapy
414, Fmidbrainlow-grade gliomaHMpineoblastomaradio- & chemotherapy
553, Mponslow-grade gliomaHMglioblastomaradiotherapy
634, Fmedullapilocytic astrocytomaHManaplastic astrocytomaradio- & chemotherapy
744, Fmidbrainlow-grade gliomaLMfibrillary astrocytomanone
867, FponsglioblastomaHMHMmetastasisradiotherapy
973, Fponsleukemic infiltrationHMacute leukemiamedical treatment
1049, FmidbrainmetastasisHMHMmetastasisradiotherapy
1118, Fponslow-grade gliomaLMLMvasculitismedical treatment
1278, MponsmetastasisHMependymomanone
1353, FponsmetastasisHMglioblastomaradiotherapy
1437, Mmedullahigh-grade gliomaHMHManaplastic astrocytomaradio- & chemotherapy
1533, Fponshigh-grade gliomaLMLMfibrillary astrocytomanone
1656, Mmidbrainhigh-grade gliomaHMHMlymphomamedical treatment
1767, MponsmetastasisLMLMmetastasisradiotherapy
1830, Fponslow-grade gliomaLMHManaplastic astrocytomaradiotherapy
1932, Mponsinfection/lymphomaHMHMleukoencephalitismedical treatment
2041, Mponslow-grade gliomaHMHMfibrillary astrocytomanone
2122, Mmedullalow-grade gliomaHMfibrillary astrocytomanone
2249, MmedullainfectionLMinfectionmedical treatment
2369, FmidbrainglioblastomaHMglioblastomaradiotherapy
2465, MmidbrainmetastasisHMglioblastomaradiotherapy
2578, FmidbrainglioblastomaLMHMglioblastomaradiotherapy
2620, FmidbrainglioblastomaHManaplastic astrocytomaradio- & chemotherapy
2742, Mponshigh-grade gliomaHMglioblastomaradiotherapy
2866, MmidbrainvasculitisHMlymphomamedical treatment
2922, Mmidbrainlow-grade gliomaLManaplastic astrocytomaradio- & chemotherapy
3069, FmidbrainglioblastomaHMglioblastomaradiotherapy

HM = high malignancy; LM = low malignancy; — = not performed.

Magnetic resonance imaging and PET studies were performed in stereotactic conditions to obtain data for the planning of the stereotactic procedure; details of the methods used for such data acquisition and planning have been previously described.18,19,24 Positron emission tomography scanning was performed with FDG in 16 patients, with Met in two patients, and with both tracers in 12 patients. Briefly, a carbon fiber head ring unit was attached to the patient's head in a normal or inverted position after application of a local anesthetic; MR imaging followed by PET scanning was performed using a four-plate localizing system, with either MR-enhancing or [18F]fluoride solution fiducials, which were fixed on the base ring and generated a 12-mark referential on MR and PET slices. Surgical planning was then performed. The target was selected as the center of the zone at which abnormal metabolism was demonstrated on PET after the image was projected onto the corresponding stereotactic MR slice. In some cases two trajectories were performed to account for the discordance between MR imaging and PET findings. The surgical aspect of the stereotactic biopsy procedure was performed in the operating room after induction of general anesthesia. Based on the location of the lesion within the brainstem, we performed a transfrontal or transcerebral approach, as described by Coffey and Lunsford.4

For the purposes of data analysis, we retrospectively reviewed the PET and MR imaging protocols made before obtaining the biopsy sample (and therefore independently of histological determinations), and the results of histological analysis of the biopsy specimen. For MR imaging, when more than one diagnosis was suggested, only the most likely was considered (Table 1), which should be the case for the management of this lesion when biopsy samples are not obtained. We used PET scanning to indicate the degree (high or low) of tumor malignancy, as shown in Table 1. We first examined the results of each imaging modality separately and compared them with histological diagnoses to define the percentage of accurate data provided by Pet alone or by MR imaging alone. We then compared the results of PET with those of MR imaging analysis and separated patients into two groups according to the agreement or disagreement between MR and PET findings. In the group in which there was discordance between PET and those of MR imaging interpretations, we determined which of those two imaging modalities provided correct information about the lesion's histological type. In cases in which there were concordant PET and MR imaging interpretations, we compared those data with histological findings to calculate the diagnostic yield of the combination of the two imaging modalities. The diagnostic yield of PET- only and/or MR imaging—only findings was evaluated to determine the superiority or complementary role of PET (Table 2).

TABLE 2

Concordance rate between the different data

No. of Patients
CodeDescriptionConcordant (%)Discordant
AMR & histological findings19 (63)11
BPET & histological findings22 (73)8
CMR & PET findings19 (63)11
Dconcordant MR/PET &
 histological findings15 (79)*4
EMR-derived & histology-derived
 treatment17 (57)13
FMR/PET-derived &
 histology-derived treatment19 (63)11

Of a total of 19 patients.

Results

Based on the location of the tumor within the brainstem, the stereotactic biopsy sample was obtained via a transfrontal approach in 12 and a transcerebellar approach in 18 patients. A total of 40 trajectories were performed in the 30 patients: three trajectories aimed at cyst aspiration and 37 biopsy trajectories (1.23 ± 0.43 [mean ± standard deviation] biopsy trajectories per patient). Until 1995, two trajectories were performed when there was a discrepancy between PET- and MR imaging—based targeting data as part of a prospective study previously published.19 More recently, because PET data have been shown to improve the diagnostic yield of biopsy sampling, we have endeavored to perform only one trajectory to lower the risks of the procedure. A precise histological diagnosis was established in all patients, and this diagnosis was confirmed by the patient's clinical course. Histological examination identified 18 gliomas, including nine glioblastomas, five anaplastic astrocytomas, and four low-grade gliomas; other lesions included three metastases, two lymphomas, one leukemic infiltration, one ependymoma, one gangliocytoma, one pineoblastoma, and three inflammatory lesions (one isolated central nervous system vasculitis and two cerebral infections).

Information provided by PET scanning, MR imaging, and histological examination in all patients is shown in Table 1. If we consider only one factor—detection of malignancy—MR imaging findings correlated with histological results in 19 patients, and PET results correlated with histological findings in 22 patients (Tables 2 and 3). In the comparison between MR imaging and PET scanning data obtained in each patient we found discordant results between the two modalities in 11 patients (37%). In cases in which there was discordance between MR and PET scanning data, MR imaging findings were in agreement with histological findings in four and PET scanning in seven cases. In only 19 patients (63%) were MR imaging and PET scanning data concordant; in this group, there was correlation between imaging and histological results in 15 cases (79%).

TABLE 3

Detailed cumulative concordance rate of the different data*

Code
Case No.ABCDEF
11
22
311
42
532
643
7153114
8264225
9375336
10486447
115975
128
136109658
1471110769
151210
16813118
1797
181411
1910812
20119
211210
2213151291113
23141613101214
24151714111315
25161815121416
26171916131517
27182017141618
2821
2918
30192219151719

— = no concordance.

In 18 patients we preferred to use PET scanning for defining the biopsy target because this modality outlined a high metabolic area either inside the tumor area, as defined on MR imaging, or near the area of gadolinium enhancement. In these 18 patients, the diagnostic yield of the image-guided biopsy procedure was 100%. In seven patients MR imaging and PET studies revealed two different target areas for biopsy; in those cases we performed one PET- and one MR imaging—defined trajectory. Histologically, in seven patients, the PET-guided biopsy samples were more representative of the tumor's nature and grade than the MR imaging—guided samples in four cases (57%).

A risk—benefit analysis of the brainstem biopsy procedure was performed. We reasoned that the patient benefited from the biopsy procedure when the treatment based on histological findings differed from the expected imaging-based therapy. Our treatment options were as follows: exophytic brainstem tumors were approached surgically; inflammatory or infectious lesions as well as lymphoma received medical treatment; conservative management was proposed for low-grade tumors; and high-grade tumors were treated with radiotherapy and/or chemotherapy. The MR imaging—based therapy was concordant with the treatment based on histological findings in 17 patients (57%). If we used PET data to define the level of malignancy of tumors detected on MR imaging, the therapy proposed on the basis of combined neuroimaging was in concordance with the treatment based on histological findings in 19 patients (63%).

The benefit of obtaining biopsy samples is illustrated by the results in one patient (Case 29), whose neuroimaging studies are shown in Fig. 1. This patient was shown to harbor a nonenhancing lesion of the midbrain on MR imaging; FDG-PET revealed hypometabolism within the tumor area. This information led us to a presumptive diagnosis of low-grade glioma. However, because anaplastic foci were found at histological examination, the definite diagnosis was anaplastic astrocytoma. We initiated appropriate radio- and chemotherapy. Another example is illustrated in the patient in Case 15 (Fig. 2); because this patient harbored a large brainstem lesion that was highly enhanced on MR imaging after administration of gadolinium, the lesion was therefore suspected to be a high-grade glioma. The absence of uptake of FDG and Met demonstrated on PET indicated a diagnosis of low-grade tumor. However, histological examination of the MR imaging—and PET-guided stereotactic biopsy sample confirmed the diagnosis of Grade II fibrillary astrocytoma.

Fig. 1.
Fig. 1.

Case 29. Upper Left: Axial T1-weighted MR image obtained after gadolinium injection demonstrating a slightly hypodense area in the right part of the midbrain, with no enhancement. Upper Right and Lower Left: The lesion appears hyperintense on fast fluid-attenuated inversion—recovery and T2-weighted MR images. Lower Right: An FDG-PET scan revealing hypometabolism within the tumor area. The stereotactic biopsy target is designated by crosshairs on the T1-weighted MR image and FDG-PET scan.

Fig. 2.
Fig. 2.

Case 15. Upper Left: Sagittal MR image obtained before gadolinium administration. Upper Right: Sagittal MR image obtained after gadolinium administration demonstrating an enhancing lesion. Lower Left and Right: Positron emission tomography scans obtained with Met (lower left) and FDG tracers (lower right). The patient harbored a large brainstem lesion that became highly enhanced on MR images obtained after injection of gadolinium; it was therefore suspected to be a high-grade glioma. However, due to the lack of FDG and Met uptake on PET scans, the diagnosis was changed to a low-grade tumor.

To estimate the safety of performing such a biopsy procedure in the brainstem, we reviewed the mortality and morbidity rates associated with this procedure. In our series, no patient died as a result of the procedure. Two patients experienced a transient worsening of their preoperative neurological deficits, but no patient suffered permanent postoperative deficits.

Discussion

In the present study, we reviewed our experience with combined MR- and PET-guided stereotactic biopsy procedures for the management of brainstem mass lesions. Even if PET helped to reinforce the diagnosis based on MR imaging, we found that imaging data may not efficiently replace biopsy sampling for the accurate determination of lesion histological features and subsequent treatment options.

Management of Mass Lesions of the Brainstem

The management of mass lesions of the brainstem remains controversial.20 Although the use of image-guided stereotactic brain biopsy sampling is regarded as a safe and reliable procedure for the management of supratentorial lesions, its application in lesions involving the brainstem remains limited.16,17 Recent progress in modern neuroimaging techniques, especially high-resolution MR imaging, allows us to determine more precisely the location and extension of brainstem tumors, and it may reveal some specific characteristics of their nature.20 Hence, the challenge is knowing whether the use of MR imaging alone is precise enough to provide an accurate diagnosis, or at least allowing for classification of patients into specific treatment groups, and, consequently, if a pathological diagnosis is still mandatory before initiating any therapy.2,25 In this context, PET may play an additional role that will help in such decision making.

Use of PET as a Diagnostic Tool for Mass Lesions of the Brainstem

Many authors have illustrated the good correlation between tumor grade and tumor metabolism as measured by PET, both with FDG or Met as markers.5,8,10–13 In many studies good correlation between the tumor grade and the PET-determined metabolism of cerebral gliomas has been demonstrated. Hypermetabolic areas observed on PET scans correspond to malignant components of these heterogeneous tumors.10,13 In other series the authors have also found a direct relation between PET-defined metabolism and prognosis.1,6,7,22

The use of PET may provide information concerning brainstem mass lesions similar to what it provides for supratentorial tumors. Actually, there is sparse information reported on PET-defined metabolism of brainstem tumors in the literature. In a study of brainstem metabolism in normal and pathological cases, Di Chiro, et al.,9 have found the same relation between tumor grade and glucose metabolism on results of PET studies in brainstem tumors as in lesions of the hemisphere. Analysis of their results emphasizes the presence of regional metabolic differences in most brainstem tumors, reflecting the malignant heterogeneity of glioma in the brainstem. In some case reports the results underscore the superiority of PET over MR imaging for brainstem tumors in demonstrating discrete tumor progression into the brainstem,3 as well as PET's superior ability to differentiate tumor progression from postirradiation edema or necrosis.14

The data derived from our series of 30 image-guided stereotactic procedures in which biopsy samples were obtained of brainstem mass lesions indicate that the degree of malignancy of the tumor is more accurately estimated using PET than MR imaging (73% and 63%, respectively). However, information provided by PET is mainly limited to what it indicates regarding the degree of malignancy and does not demonstrate the nature of the tumor or its precise location, as does MR imaging. Therefore, we find that PET- and MR imaging—defined data are complementary in the management of brainstem tumors. In this series, when these two complementary modalities provided concordant data, the diagnostic yield of cerebral imaging was increased up to 79%. However, in 43% of the patients MR imaging and PET scanning provided discordant findings, and in four patients unexpected histological results were demonstrated despite the correlation of MR and PET data; therefore, the need to obtain a histological diagnosis by performing a stereotactic biopsy procedure before initiating therapy remains, in our opinion, essential.

Use of PET as a Localizing Tool for Stereotactic Biopsy

In most series found in recent literature, conventional computerized tomography— or MR imaging—guided stereotactic biopsy sampling of brainstem lesions yielded appropriate results in 90 to 95% of cases.16,17,26 In this series, the MR imaging— and PET-based stereotactic biopsy specimens allowed us to make precise histological diagnoses in all patients. The incorporation of PET in the stereotactic planning allows us better to define the appropriate target at which to obtain the biopsy sample and, therefore, to increase the diagnostic yield. Moreover, because better targeting will decrease the number of biopsy trajectories and samples, the risk of injuring the brainstem will be reduced.

We have demonstrated in our series that in some cases the biopsy target was more accurately defined using PET than MR imaging and that PET-based targeting increased the diagnostic yield of the biopsy procedure. These results are in accordance with those reported in our previous prospective study in which we demonstrated that, for stereotactic biopsy sampling of cerebral tumors, the inclusion of PET in the biopsy planning procedure will provide better targeting.15,19,24 In this study, most PET scanning has been performed using both FDG and Met tracers in a prospective manner so as to allow for analysis of information provided by each tracer; the results of our earlier study have been published recently and demonstrate the close correlation and complementary role of FDG and Met for target selection in stereotactic brain biopsy procedures.12,24

Conclusions

In this study, we have demonstrated that although the use of MR imaging and PET scanning improves the diagnostic yield of brainstem mass lesions, cerebral neuroimaging alone is unable to provide in all cases sufficient information on brainstem tumors to specify adequately the required treatment without histological examination. A PET- and MR imaging—guided stereotactic procedure in the brainstem is a low-risk and accurate procedure that permits pathological diagnosis before initiating the appropriate treatment.

References

  • 1.

    Alavi JBAlavi AChawluk Jet al: Positron emission tomography in patients with glioma. A predictor of prognosis. Cancer 62:107410781988Cancer 62:

  • 2.

    Albright ALPacker RJZimmerman Ret al: Magnetic resonance scans should replace biopsies for the diagnosis of diffuse brainstem gliomas: a report from the Children's Cancer Group. Neurosurgery 33:102610301993Neurosurgery 33:

  • 3.

    Bruggers CFriedman HSFuller GNet al: Comparison of serial PET and MRI scans in a pediatric patient with a brainstem glioma. Med Pediatr Oncol 21:3013061993Med Pediatr Oncol 21:

  • 4.

    Coffey RJLunsford LD: Stereotactic surgery for mass lesions of the midbrain and pons. Neurosurgery 17:12181985Neurosurgery 17:

  • 5.

    Derlon JMBourdet CBustany Pet al: [11C]L-methionine uptake in gliomas. Neurosurgery 25:720728198911C]L-methionine uptake in gliomas. Neurosurgery 25:

  • 6.

    De Witte OLefranc FLevivier Met al: FDG-PET as a prognostic factor in high-grade astrocytoma. J Neurooncol J Neurooncol

  • 7.

    De Witte OLevivier MViolon Pet al: Prognostic value of positron emission tomography with [18F]fluoro-2-deoxy-D-glucose in the low-grade glioma. Neurosurgery 39:470477199618F]fluoro-2-deoxy-D-glucose in the low-grade glioma. Neurosurgery 39:

  • 8.

    Di Chiro G: Positron emission tomography using [18F]fluorodeoxyglucose in brain tumors. A powerful diagnostic and prognostic tool. Invest Radiol 22:3603711987Di Chiro G: Positron emission tomography using [18F]fluorodeoxyglucose in brain tumors. A powerful diagnostic and prognostic tool. Invest Radiol 22:

  • 9.

    Di Chiro GDeLaPaz RLBrooks RAet al: Glucose utilization of cerebral gliomas measured by [18F]fluorodeoxyglucose and positron emission tomography. Neurology 32:13231329198218F]fluorodeoxyglucose and positron emission tomography. Neurology 32:

  • 10.

    Di Chiro GOldfield EBairamian Det al: Metabolic imaging of the brainstem and spinal cord: studies with positron emission tomography using 18F-2-deoxyglucose in normal and pathological cases. J Comput Assist Tomogr 7:9379451983J Comput Assist Tomogr 7:

  • 11.

    Francavilla TLMiletich RSDi Chiro Get al: Positron emission tomography in the detection of malignant degeneration of low-grade gliomas. Neurosurgery 24:151989Neurosurgery 24:

  • 12.

    Goldman SLevivier MPirotte Bet al: Regional glucose metabolism and histopathology of gliomas. A study based on positron emission tomography-guided stereotactic biopsy. Cancer 78:109811061996Cancer 78:

  • 13.

    Goldman SLevivier MPirotte Bet al: Regional methionine and glucose uptake in high-grade gliomas: a comparative study on PET-guided stereotactic biopsy. J Nucl Med 38:145914621997J Nucl Med 38:

  • 14.

    Griebel MFriedman HSHalperin ECet al: Reversible neurotoxicity following hyperfractionated radiation therapy of brainstem glioma. Med Pediatr Oncol 19:1821861991Med Pediatr Oncol 19:

  • 15.

    Hanson MWGlantz MJHoffman JMet al: FDG-PET in the selection of brain lesions for biopsy. J Comput Assist Tomogr 15:7968011991J Comput Assist Tomogr 15:

  • 16.

    Kondziolka DLunsford LD: Results and expectations with image-integrated brainstem stereotactic biopsy. Surg Neurol 43:5585621995Surg Neurol 43:

  • 17.

    Kratimenos GPThomas DGT: The role of image-directed biopsy in the diagnosis and management of brainstem lesions. Br J Neurosurg 7:1551641993Br J Neurosurg 7:

  • 18.

    Levivier MGoldman SBidaut Let al: Positron emission tomography-guided stereotactic brain biopsy. Neurosurgery 31:7927971992Neurosurgery 31:

  • 19.

    Levivier MGoldman SPirotte Bet al: Diagnostic yield of stereotactic brain biopsy guided by positron emission tomography with [18F]fluorodeoxyglucose. J Neurosurg 82:445452199518F]fluorodeoxyglucose. J Neurosurg 82:

  • 20.

    Levivier MMassager NBrotchi J: Management of mass lesions of the brainstem. Crit Rev Neurosurg 8:3383451998Crit Rev Neurosurg 8:

  • 21.

    Maciunas RJKessler RMMaurer Cet al: Positron emission tomography imaging-directed stereotactic neurosurgery. Stereotact Funct Neurosurg 58:1341401992Stereotact Funct Neurosurg 58:

  • 22.

    Patronas NJDi Chiro GKufta Cet al: Prediction of survival in glioma patients by means of positron emission tomography. J Neurosurg 62:8168221985J Neurosurg 62:

  • 23.

    Pierre-Kahn AHirsch JFVinchon Met al: Surgical management of brain-stem tumors in children: results and statistical analysis of 75 cases. J Neurosurg 79:8458521993J Neurosurg 79:

  • 24.

    Pirotte BGoldman SDavid Pet al: Stereotactic brain biopsy guided by positron emission tomography (PET) with [F-18]fluorodeoxyglucose and [C-11]methionine. Acta Neurochir Suppl 68:1331381997Acta Neurochir Suppl 68:

  • 25.

    Rajshekhar VChandy MJ: Computerized tomography-guided stereotactic surgery for brainstem masses: a risk-benefit analysis in 71 patients. J Neurosurg 82:9769811995J Neurosurg 82:

  • 26.

    Ranjan ARajshekhar VJoseph Tet al: Nondiagnostic CT-guided stereotactic biopsies in a series of 407 cases: influence of CT morphology and operator experience. J Neurosurg 79:8398441993J Neurosurg 79:

An earlier version of this manuscript was published in Neurosurg Focus 8 (2):Article 1, 2000.

Article Information

Address reprint requests to: Marc Levivier, M.D., Ph.D., Department of Neurosurgery, Université Libre de Bruxelles, Erasme Hospital, Route de Lennik 808, B-1070 Brussels, Belgium. email: mlev@ulb.ac.be.

© AANS, except where prohibited by US copyright law.

Headings

Figures

  • View in gallery

    Case 29. Upper Left: Axial T1-weighted MR image obtained after gadolinium injection demonstrating a slightly hypodense area in the right part of the midbrain, with no enhancement. Upper Right and Lower Left: The lesion appears hyperintense on fast fluid-attenuated inversion—recovery and T2-weighted MR images. Lower Right: An FDG-PET scan revealing hypometabolism within the tumor area. The stereotactic biopsy target is designated by crosshairs on the T1-weighted MR image and FDG-PET scan.

  • View in gallery

    Case 15. Upper Left: Sagittal MR image obtained before gadolinium administration. Upper Right: Sagittal MR image obtained after gadolinium administration demonstrating an enhancing lesion. Lower Left and Right: Positron emission tomography scans obtained with Met (lower left) and FDG tracers (lower right). The patient harbored a large brainstem lesion that became highly enhanced on MR images obtained after injection of gadolinium; it was therefore suspected to be a high-grade glioma. However, due to the lack of FDG and Met uptake on PET scans, the diagnosis was changed to a low-grade tumor.

References

1.

Alavi JBAlavi AChawluk Jet al: Positron emission tomography in patients with glioma. A predictor of prognosis. Cancer 62:107410781988Cancer 62:

2.

Albright ALPacker RJZimmerman Ret al: Magnetic resonance scans should replace biopsies for the diagnosis of diffuse brainstem gliomas: a report from the Children's Cancer Group. Neurosurgery 33:102610301993Neurosurgery 33:

3.

Bruggers CFriedman HSFuller GNet al: Comparison of serial PET and MRI scans in a pediatric patient with a brainstem glioma. Med Pediatr Oncol 21:3013061993Med Pediatr Oncol 21:

4.

Coffey RJLunsford LD: Stereotactic surgery for mass lesions of the midbrain and pons. Neurosurgery 17:12181985Neurosurgery 17:

5.

Derlon JMBourdet CBustany Pet al: [11C]L-methionine uptake in gliomas. Neurosurgery 25:720728198911C]L-methionine uptake in gliomas. Neurosurgery 25:

6.

De Witte OLefranc FLevivier Met al: FDG-PET as a prognostic factor in high-grade astrocytoma. J Neurooncol J Neurooncol

7.

De Witte OLevivier MViolon Pet al: Prognostic value of positron emission tomography with [18F]fluoro-2-deoxy-D-glucose in the low-grade glioma. Neurosurgery 39:470477199618F]fluoro-2-deoxy-D-glucose in the low-grade glioma. Neurosurgery 39:

8.

Di Chiro G: Positron emission tomography using [18F]fluorodeoxyglucose in brain tumors. A powerful diagnostic and prognostic tool. Invest Radiol 22:3603711987Di Chiro G: Positron emission tomography using [18F]fluorodeoxyglucose in brain tumors. A powerful diagnostic and prognostic tool. Invest Radiol 22:

9.

Di Chiro GDeLaPaz RLBrooks RAet al: Glucose utilization of cerebral gliomas measured by [18F]fluorodeoxyglucose and positron emission tomography. Neurology 32:13231329198218F]fluorodeoxyglucose and positron emission tomography. Neurology 32:

10.

Di Chiro GOldfield EBairamian Det al: Metabolic imaging of the brainstem and spinal cord: studies with positron emission tomography using 18F-2-deoxyglucose in normal and pathological cases. J Comput Assist Tomogr 7:9379451983J Comput Assist Tomogr 7:

11.

Francavilla TLMiletich RSDi Chiro Get al: Positron emission tomography in the detection of malignant degeneration of low-grade gliomas. Neurosurgery 24:151989Neurosurgery 24:

12.

Goldman SLevivier MPirotte Bet al: Regional glucose metabolism and histopathology of gliomas. A study based on positron emission tomography-guided stereotactic biopsy. Cancer 78:109811061996Cancer 78:

13.

Goldman SLevivier MPirotte Bet al: Regional methionine and glucose uptake in high-grade gliomas: a comparative study on PET-guided stereotactic biopsy. J Nucl Med 38:145914621997J Nucl Med 38:

14.

Griebel MFriedman HSHalperin ECet al: Reversible neurotoxicity following hyperfractionated radiation therapy of brainstem glioma. Med Pediatr Oncol 19:1821861991Med Pediatr Oncol 19:

15.

Hanson MWGlantz MJHoffman JMet al: FDG-PET in the selection of brain lesions for biopsy. J Comput Assist Tomogr 15:7968011991J Comput Assist Tomogr 15:

16.

Kondziolka DLunsford LD: Results and expectations with image-integrated brainstem stereotactic biopsy. Surg Neurol 43:5585621995Surg Neurol 43:

17.

Kratimenos GPThomas DGT: The role of image-directed biopsy in the diagnosis and management of brainstem lesions. Br J Neurosurg 7:1551641993Br J Neurosurg 7:

18.

Levivier MGoldman SBidaut Let al: Positron emission tomography-guided stereotactic brain biopsy. Neurosurgery 31:7927971992Neurosurgery 31:

19.

Levivier MGoldman SPirotte Bet al: Diagnostic yield of stereotactic brain biopsy guided by positron emission tomography with [18F]fluorodeoxyglucose. J Neurosurg 82:445452199518F]fluorodeoxyglucose. J Neurosurg 82:

20.

Levivier MMassager NBrotchi J: Management of mass lesions of the brainstem. Crit Rev Neurosurg 8:3383451998Crit Rev Neurosurg 8:

21.

Maciunas RJKessler RMMaurer Cet al: Positron emission tomography imaging-directed stereotactic neurosurgery. Stereotact Funct Neurosurg 58:1341401992Stereotact Funct Neurosurg 58:

22.

Patronas NJDi Chiro GKufta Cet al: Prediction of survival in glioma patients by means of positron emission tomography. J Neurosurg 62:8168221985J Neurosurg 62:

23.

Pierre-Kahn AHirsch JFVinchon Met al: Surgical management of brain-stem tumors in children: results and statistical analysis of 75 cases. J Neurosurg 79:8458521993J Neurosurg 79:

24.

Pirotte BGoldman SDavid Pet al: Stereotactic brain biopsy guided by positron emission tomography (PET) with [F-18]fluorodeoxyglucose and [C-11]methionine. Acta Neurochir Suppl 68:1331381997Acta Neurochir Suppl 68:

25.

Rajshekhar VChandy MJ: Computerized tomography-guided stereotactic surgery for brainstem masses: a risk-benefit analysis in 71 patients. J Neurosurg 82:9769811995J Neurosurg 82:

26.

Ranjan ARajshekhar VJoseph Tet al: Nondiagnostic CT-guided stereotactic biopsies in a series of 407 cases: influence of CT morphology and operator experience. J Neurosurg 79:8398441993J Neurosurg 79:

TrendMD

Metrics

Metrics

All Time Past Year Past 30 Days
Abstract Views 3 3 3
Full Text Views 54 54 30
PDF Downloads 42 42 25
EPUB Downloads 0 0 0

PubMed

Google Scholar