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Surgical results for spinal meningiomas
Surgical Results for Spinal Meningiomas Jo ¨ rg Klekamp, M.D. and Madjid Samii, M.D. Medical School of Hannover, Neurosurgical Clinic, Nordstadt Hospital, Hannover, Germany
Klekamp J, Samii M. Surgical results for spinal meningiomas. Surg Neurol 1999;52:552– 62.
Among a series of 782 spinal tumors, 130 spinal meningiomas in 117 patients were operated in the Department of Neurosurgery at the Nordstadt Hospital in Hannover, Germany, between 1977 and 1998. Patients were followed postoperatively for up to 13 years (mean 20 ⫾ 33 months). Comparing the period of 1977 through 1987, before magnetic resonance imaging (MRI) was available, to the period of 1988 to 1998 revealed that the average history until diagnosis shortened by about 6 months during the second decade of this study (24 ⫾ 33 to 18 ⫾ 29 months; not significant). Consequently, the preoperative Karnofsky Score increased significantly (59 ⫾ 15 and 66 ⫾ 16; p ⬍ 0.05). The rates of complete resection and the postoperative neurological outcome, however, remained unchanged. Even though the overall prognosis of neurological deficits is favorable after complete resection of a meningioma, a subset of 18 patients had either en plaque growing or recurrent tumors that were more likely to be removed incompletely and to cause postoperative neurological problems, with a significantly worse Karnofsky Score after 1 year (57 ⫾ 12 and 77 ⫾ 12, respectively; p ⬍ 0.01) and a significantly higher recurrence rate after 5 years (86.7% and 20.4%, respectively; log rank test p ⫽ 0.0014). In conclusion, a favorable postoperative neurological outcome requires complete resection of the spinal meningioma. The advent of MRI has shortened the time until diagnosis and made it possible to perform surgery before severe deficits have occurred, but did not have a major impact on postoperative results. En plaque and recurrent meningiomas remain surgical challenges, as infiltration of surrounding structures and associated arachnoid scarring may render complete resection difficult to achieve. © 1999 by Elsevier Science Inc. KEY WORDS
Arachnoiditis, spinal neoplasms.
t is well established that spinal meningiomas carry an excellent prognosis in general [1,2,4 –7, 10,11,14,18,22,23,25,27,29,32,33]. However, a number of factors such as arachnoid scarring associ-
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Address reprint requests to: Dr. Klekamp, Nordstadt Hospital, Neurosurgical Clinic, Haltenhoffstr.41, D-30167 Hannover, Germany. Received November 29, 1995; accepted August 11, 1999. 0090-3019/99/$–see front matter PII S0090-3019(99)00153-6
ated with recurrent tumors, the growth pattern of the tumor, and the influence of magnetic resonance imaging (MRI) have not been evaluated. This study will analyze the impact of these factors on diagnosis, surgical strategy and postoperative outcome.
Material and Methods During the period between 1977 and 1998, a total of 782 spinal tumors were operated in our department. Among these, 130 meningiomas in 117 patients were removed. Case records, operative reports, follow-up information, and neuroradiological findings were evaluated. Additional data were obtained by questionnaires or telephone calls. The clinical course was documented using the Karnofsky Score [17] and a score system for each symptom [19] (Table 1). In general, scores between 3 and 5 describe satisfactory levels of function and scores between 0 and 2 indicate unsatisfactory or incapacitated functions. For analysis of sensory function or motor power only the most affected part of the body was evaluated. Preoperative imaging consisted of plain X-rays of the affected spinal segments and a myelogram with postmyelographic computed tomography (CT) before MRI was available. This period lasted from 1977 to 1987. Since 1988, MRI has replaced myelography and CT and is the imaging modality of choice. Surgery consisted of a laminectomy or laminotomy with intraoperative fluoroscopic control. Depending on the dural attachment (⫽ tumor matrix), a facet joint or the proximal part of a rib were resected to gain access to anterior tumors. After dural opening care was taken to preserve the arachnoidal sheath at the interface between tumor and spinal cord to protect the cord and its blood supply. Posteriorly placed tumors were generally removed in toto including the dural attachment (Figure 1). The dural defect was closed with a duraplasty. For anterior or lateral meningiomas, the tumor was © 1999 by Elsevier Science Inc. 655 Avenue of the Americas, New York, NY 10010
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Neurological Scoring System
SCORE 5 4 3 2 1 0
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SENSORY DEFICITS, PAIN, DYSESTHESIAS
MOTOR WEAKNESS
GAIT ATAXIA
No Symptom Present, Not Significant Significant, Function Not Restricted Some Restriction Of Function Severe Restriction Of Function Incapacitated
Full Power Movement Against Resistance Movement Against Gravity Movement Without Gravity Contraction Without Plegia
Normal Unsteady No Aid Mobile With Aid
BLADDER FUNCTION Normal Slight Dist., No Catheter Residual, No Cath.
BOWEL FUNCTION Normal Slight Dist., Full Control Laxatives, Full Control
Few Steps With Aid Sometimes Catheter Sometimes Loss Of Control Standing With Aid Often Catheter Often Loss Of Control Wheel Chair
Permanent Catheter No Control
Abbreviations: Dist. ⫽ disturbance; Cath. ⫽ catheter.
debulked first and then the capsule was dissected free and removed. The dural attachment was either coagulated or the inner dural layer was resected (Figure 2). With recurrent meningiomas such an arachnoidal interface was not present in most instances. Consequently, the attachment of the tumor to neighboring structures was tighter. Nerve roots and vessels were often encased and sometimes even the pia mater was infiltrated. Likewise, en plaque growing tumors were devoid of a capsule and tended to infiltrate surrounding structures (Figure 3). The tumor matrix tended to be more extensive. Using microsurgical techniques, these tumors were debulked first. The tumor mass could be resected completely except in cases of meningiomas with pia infiltration. With recurrent meningiomas, severe arachnoid scarring sometimes made it impossible
to clearly distinguish between scar, meningioma, and cord. Especially with anterior extension of such a tumor, it was our policy to leave a small amount of tumor in place rather than risk permanent neurological deficits. Postoperatively, every patient received plain X-rays and—since the advent of MRI—a gadolinium enhanced MRI scan after 3 months. Further scans were performed if the clinical situation deteriorated or if the tumor removal had been incomplete. Postoperative clinical examinations were performed at discharge and after 3 months. Additional follow-up information was obtained by further outpatient examinations, telephone calls or questionnaires.
Posterior en plaque meningioma in a 71-year-old patient with sensory deficits, dysesthesias, motor weakness, and gait ataxia. The tumor was removed completely including the dural attachment. The patient recovered completely and is without recurrence 2 years postoperatively.
Anterior meningioma at C2 in a 62-year-old woman with neck pain, gait ataxia, motor weakness, and sensory deficits. The tumor was removed completely with cauterization of the tumor matrix. The patient made a complete recovery and is without a recurrence 3 years postoperatively.
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Pre- (A, B) and postoperative (C) MRI scans with gadolinium in a 68-year-old woman with a recurrent en plaque growing meningioma at the cervicothoracic junction. The tumor had infiltrated the dura and leptomeninges, encircling the cord completely. Part of the tumor was calcified. The meningioma was removed partially and a fascia lata graft was inserted to decompress the subarachnoid space. Postoperatively, the patient remained neurologically stable. However, severe dysesthesias and spasms in her lower extremities continue to prevent mobilization, rendering her confined to a wheelchair.
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The postoperative course was analyzed according to the symptom scores outlined above and by determining the percentage of patients who experi-
enced progressive neurological deterioration postoperatively using Kaplan-Meier statistics [16]. Such clinical progression was either due to recurrent
Spinal Meningiomas
tumor or delayed postoperative morbidity related to arachnoid scarring, syringomyelia or instability, and myelopathy. Means are presented plus/minus the standard deviation. For statistical analyses Student’s t test for paired or unpaired variables and the chi-square test were used provided the Komolgorov– Smirnov test indicated normal data distribution. Statistical differences for rates of neurological progression were determined using the log rank test. A difference was considered significant if a p-value of 0.05 was reached.
Results CLINICAL DATA During the study period 117 patients were operated for 130 spinal meningiomas. The average age was 57 ⫾ 15 years (range 17 to 86 years). Female sex predominated by a factor of 3.9:1 (24 males and 93 females). The average history until admission for surgery was 19 ⫾ 30 months. The majority of patients presented a slowly progressive course which started with pain or dysesthesias in 50% of all patients. Twenty-two percent noticed gait problems as the first symptom, 16% motor weakness, and 12% sphincter disturbances or sensory deficits. In one particular case, the history dated back for 18 years before the diagnosis was made. Since the advent of MRI in our institution in 1988, we observed a shortening of the average preoperative history by about 6 months (24 ⫾ 33 months and 18 ⫾ 29 months, respectively; not significant). For recurrent meningiomas, the diagnosis was reached significantly earlier compared to patients without a history of a previous neurosurgical intervention (13 ⫾ 18 months and 21 ⫾ 31 months, respectively; p ⬍ 0.05). Likewise, the history of en plaque growing tumors was shorter compared to encapsulated meningiomas (11 ⫾ 10 months and 22 ⫾ 33 months, respectively; p ⬍ 0.01). SYMPTOMS AND SIGNS ON ADMISSION On admission, 59% demonstrated gait ataxia as the predominating neurological symptom. Twenty percent complained of pain, 16% of motor weakness, 5% of dysesthesias, and 1% of sensory deficits as the major clinical problem. Since the advent of MRI, patients were referred earlier and with less severe neurological deficits than previously. Preoperative scores for motor power (2.8 ⫾ 1.2 and 3.4 ⫾ 1.2, respectively; p ⬍ 0.01) and gait (2.8 ⫾ 1.1 and 3.2 ⫾ 1.3, respectively; p ⬍ 0.05) increased significantly
Surg Neurol 555 1999;52:552–62
and the average preoperative Karnofsky Score improved from 59 ⫾ 17 to 66 ⫾ 16 (p ⬍ 0.05). SURGICAL FINDINGS Twenty-seven percent of all meningiomas were found in the cervical, 67% in the thoracic, and 6% in the lumbosacral spine. The tumor matrix was posterior in 28%, anterior in 27%, and lateral in 45% of all cases. Ten meningiomas (8%) demonstrated extradural extension (Figure 4). Although 103 meningiomas presented a well-defined capsule displacing surrounding structures, 27 were devoid of a capsule and infiltrated nerve roots, pia mater, dura mater and/or bone. One of these meningiomas showed ossifications (Figure 3). Twenty operations dealt with recurrent meningiomas. Only 7 of these recurrent tumors presented a tumor capsule; 13 did not (chi-square test: p ⬍ 0.0001). Compared to 11% of primary operated meningiomas, 90% of recurrent meningiomas were associated with arachnoid scarring or adhesions causing additional cord tethering (chi-square test: p ⬍ 0.0001). Compared to 14% of encapsulated meningiomas, this finding was also more prominent for en plaque growing meningiomas (chi-square test: p ⫽ 0.0005). SURGICAL RESULTS Complete resections were achieved for 115 (89%) meningiomas. We did not observe a difference comparing the early cases before 1988 to those thereafter (89% and 88%, respectively). However, different rates of complete resections were seen according to growth pattern (97% of encapsulated and 53% of en plaque meningiomas, respectively; chi-square test: p ⬍ 0.0001), number of previous surgeries (95% for first operations and 45% for recurrent tumors; chi-square test: p ⬍ 0.0001), and additional arachnoid scarring (94% without arachnoid scarring and 70% with additional scarring, respectively; chi-square test: p ⫽ 0.0013). Complications occurred in 11.2% of surgeries (Table 2). Two patients died during their postoperative hospital stay within 30 days from aspiration pneumonia and myocardial infarction (surgical mortality 1.5%), and an additional 4 patients died during the first postoperative year due to cardiac and respiratory problems unrelated to the spinal meningioma. NEUROLOGICAL OUTCOME Patients were followed for up to 13 years (20 ⫾ 33 months). In general, the prognosis for neurological recovery is excellent. Of 31 patients unable to walk preoperatively, 29% could walk before discharge from hospital. Within 3 months of rehabilitation this figure rose to 57% and after 1 year, 80% were again
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Lateral meningioma with extradural extension in a 67-year-old patient with gait ataxia, motor weakness, sensory deficits, and dysesthesias. The tumor was removed completely with resection of the dura. Postoperatively, the patient made a complete recovery.
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able to walk independently. Due to this excellent neurological recovery, no significant difference in outcome was observed between patients operated between 1977 and 1987 and those operated since 1988, although a tendency toward faster recovery of function was seen in the second decade, presum-
ably due to earlier diagnosis. Table 3 gives an overview of postoperative neurological scores for the first postoperative year. For encapsulated meningiomas and meningiomas operated on for the first time, every neurological score improved during the first postoperative year. Twelve percent of these
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Complications
TYPE OF COMPLICATION Infection Aseptic Meningitis CSF Leak, Pseudomeningocele Hemorrhage Instability Aspiration Pneumonia Urinary Tract Infection Myocardial Infarction Postoperative Permanent Deficit Total
ENCAPSULATED
EN PLAQUE
1 1 2
— — 3
1 1 1 1 1 —
— — — — — 1
9
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patients experienced a transient postoperative worsening of neurological symptoms, which recovered within 6 months. For infiltrative or recurrent meningiomas only 5% showed a transient neurological deterioration, due to the less aggressive surgical strategy for these patients. A permanent neurological deficit was observed in only one patient with an infiltrative meningioma. However, this low figure for surgical morbidity was associated with significantly worse postoperative neurological scores after one year for almost all symptoms and Karnofsky Scores (Table 3). If a complete resection was achieved, postoperative neurological scores and Karnofsky Scores were similar to those for encapsulated meningiomas. RECURRENCE RATES The overall recurrence rates for spinal meningiomas as calculated by the Kaplan–Meier method were 21% after one year and 40.3% after 5 years. A multiple regression analysis revealed that significantly higher recurrence rates have to be expected with en plaque or infiltrating meningiomas, tumors associated with arachnoid scarring, and after partial resections (Table 4). We saw higher recurrence rates for infiltrative tumors compared to encapsulated meningiomas after 1 year (49.5% and 7.9%, respectively; log rank test: p ⫽ 0.0037) and after 5 years (81.1% and 20.4%, respectively, log rank test: p ⫽ 0.0004) (Figure 5). After complete or partial resection, the corresponding figures were 14.6% and 52% after 1 year (log rank test: p ⫽ 0.0117) and 29.5% and 100% after 5 years (log rank test: p ⫽ 0.0011) (Figure 6). There was no statistical difference between patients in whom the tumor matrix was coagulated or resected (18.8% and 13.4% after 1 year, respectively; 26.1% and 31.3% after 5 years, respectively; log rank test: not significant) (Figure
6). For meningiomas associated with arachnoid scarring, we observed significantly higher clinical recurrence rates compared to meningiomas without such arachnoid changes (51.7% and 11.2% after one year, respectively; log rank test: p ⫽ 0.0002; 67.8% and 31.5% after 5 years, respectively; log rank test: p ⫽ 0.0003) (Figure 7). Comparing first surgeries and recurrent meningiomas, recurrence rates were 12.5% and 62.1% after one year (log rank test: p ⬍ 0.0001), and 30% and 87.4% after 5 years, respectively (log rank test: p ⬍ 0.0001) (Figure 8).
Discussion This retrospective study on spinal meningiomas revealed that MRI has led to earlier diagnosis of these tumors, shortened the preoperative history and thus improved the preoperative neurological status of these patients who can now be operated before severe deficits have occurred. We also identified a subset of patients whose tumors were more difficult to remove and who recover less well postoperatively and are more prone to experience recurrences. The demographics of patients with spinal meningiomas have been described extensively in previous reports [1–7,10,11,13,14,18,22,23,25–29,32,33, 36]. Even though the diagnosis has been made easier with MRI nowadays, the postoperative outcome of patients with spinal meningiomas has not improved significantly in the last decade. However, even in patients with severe preoperative neurological deficits complete resection of spinal meningiomas is followed by full neurological recovery in most instances with appropriate rehabilitation [1,2, 4 –7,10,11,13,14,18,22,23,25,27,29,32,33]. Transient neurological worsening may occur due to dissection [5] or vasogenic edema [12], but recovers within 6 months. Therefore, compared to patients treated before 1987, only a tendency toward faster neurological recovery was observed in patients operated in the second decade of this study. The figures for recurrence rates given in this study may seem higher than those reported in the literature with 6% [32] and 10 to 15% [25]. However, these studies did not use Kaplan–Meier statistics that account for varying follow-up times. Therefore, these numbers grossly underestimate the rate of patients who will have a recurrence after several years. In total, 14.7% of our patients demonstrated a recurrence— 6.9% of those with encapsulated meningiomas and 36.8% of patients with en plaque meningiomas. These figures correspond to recurrence rates of 21% (7.9% for encapsulated and 49.5% for en plaque meningiomas, respectively) after 1
558 Surg Neurol 1999;52:552–62
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Klekamp, Samii
Clinical Course of Patients with Spinal Meningiomas
GROUP/SYMPTOM Pain Encapsulated En plaque First Surgery Recurrent Tumor 1977–1987 1988–1998 Total Dysesthesias Encapsulated En plaque First Surgery Recurrent Tumor 1977–1987 1988–1998 Total Sensory Deficits Encapsulated En plaque First Surgery Recurrent Tumor 1977–1987 1988–1998 Total Motor Weakness Encapsulated En plaque First Surgery Recurrent Tumor 1977–1987 1988–1998 Total Gait Encapsulated En plaque First Surgery Recurrent Tumor 1977–1987 1988–1998 Total Bladder Function Encapsulated En plaque First Surgery Recurrent Tumor 1977–1987 1988–1998 Total Bowel Function Encapsulated En plaque First Surgery Recurrent Tumor 1977–1987 1988–1998 Total Karnofsky Score Encapsulated En plaque First Surgery Recurrent Tumor 1977–1987 1988–1998 Total
N
PREOP.
POSTOP.
3 MONTHS
6 MONTHS
36 10 42 8 16 34 50
3.4 ⫾ 1.1 3.0 ⫾ 1.3 3.4 ⫾ 1.1 3.0 ⫾ 1.5 3.5 ⫾ 1.1 3.2 ⫾ 1.2 3.3 ⫾ 1.2
4.0 ⫾ 0.7 3.8 ⫾ 0.9 4.0 ⫾ 0.7 3.4 ⫾ 0.7 3.8 ⫾ 0.8 4.0 ⫾ 0.8 3.9 ⫾ 0.8
4.4 ⫾ 0.6 4.0 ⫾ 1.1 4.4 ⫾ 0.6 3.4 ⫾ 0.9 4.3 ⫾ 0.7 4.2 ⫾ 0.8 4.3 ⫾ 0.8
4.4 ⫾ 0.6 3.9 ⫾ 1.2 4.5 ⫾ 0.6 3.3 ⫾ 1.0 4.3 ⫾ 0.7 4.3 ⫾ 0.9 4.3 ⫾ 0.8
4.4 ⫾ 0.7 3.4 ⫾ 1.8 4.4 ⫾ 0.7** 2.8 ⫾ 1.6 4.3 ⫾ 0.8 4.1 ⫾ 1.2 4.2 ⫾ 1.1
36 10 42 8 16 34 50
3.8 ⫾ 1.1 3.9 ⫾ 1.4 3.9 ⫾ 1.0 3.5 ⫾ 1.3 4.1 ⫾ 1.1 3.8 ⫾ 1.1 3.9 ⫾ 1.1
4.3 ⫾ 0.8 4.4 ⫾ 0.8 4.4 ⫾ 0.8 4.1 ⫾ 0.8 4.4 ⫾ 0.8 4.3 ⫾ 0.8 4.3 ⫾ 0.8
4.5 ⫾ 0.6 4.3 ⫾ 0.8 4.5 ⫾ 0.6 4.1 ⫾ 0.8 4.6 ⫾ 0.5 4.4 ⫾ 0.7 4.5 ⫾ 0.7
4.6 ⫾ 0.6 4.1 ⫾ 1.1 4.6 ⫾ 0.6 3.9 ⫾ 1.1 4.6 ⫾ 0.5 4.4 ⫾ 0.8 4.5 ⫾ 0.7
4.6 ⫾ 0.6* 3.5 ⫾ 1.4 4.5 ⫾ 0.6* 3.4 ⫾ 1.5 4.6 ⫾ 0.6 4.2 ⫾ 1.0 4.4 ⫾ 0.9
36 10 42 8 16 34 50
3.1 ⫾ 0.9 2.4 ⫾ 1.6 3.1 ⫾ 0.8 2.1 ⫾ 1.7 2.9 ⫾ 1.0 3.0 ⫾ 1.1 3.0 ⫾ 1.0
3.7 ⫾ 1.0 2.6 ⫾ 1.8 3.7 ⫾ 0.9 2.1 ⫾ 2.0 3.1 ⫾ 1.4 3.6 ⫾ 1.2 3.4 ⫾ 1.4
4.1 ⫾ 1.0 2.8 ⫾ 2.0 4.0 ⫾ 0.9 2.3 ⫾ 2.1 3.6 ⫾ 1.4 3.9 ⫾ 1.3 3.8 ⫾ 1.3
4.1 ⫾ 1.0 2.9 ⫾ 2.1 4.1 ⫾ 1.0 2.1 ⫾ 2.1 3.8 ⫾ 1.5 3.9 ⫾ 1.4 3.8 ⫾ 1.4
4.2 ⫾ 1.1* 2.8 ⫾ 2.1 4.2 ⫾ 1.0** 2.0 ⫾ 2.1 3.8 ⫾ 1.5 3.9 ⫾ 1.4 3.8 ⫾ 1.4
36 10 42 8 16 34 50
2.9 ⫾ 1.1 3.1 ⫾ 1.4 3.0 ⫾ 1.1 3.3 ⫾ 1.5 2.8 ⫾ 1.4 3.2 ⫾ 1.1 3.1 ⫾ 1.2
3.4 ⫾ 1.1 3.4 ⫾ 1.2 3.6 ⫾ 1.1 3.3 ⫾ 1.5 3.2 ⫾ 1.1 3.7 ⫾ 1.1 3.5 ⫾ 1.1
3.9 ⫾ 1.0 3.8 ⫾ 1.0 4.0 ⫾ 0.9 3.3 ⫾ 1.4 3.7 ⫾ 1.1 4.0 ⫾ 1.0 3.9 ⫾ 1.0
4.2 ⫾ 1.0 3.9 ⫾ 1.1 4.4 ⫾ 0.8 3.1 ⫾ 1.5 3.9 ⫾ 1.0 4.3 ⫾ 1.0 4.2 ⫾ 1.0
4.3 ⫾ 0.9* 3.6 ⫾ 1.3 4.4 ⫾ 0.8* 2.6 ⫾ 1.8 4.0 ⫾ 1.1 4.2 ⫾ 1.2 4.1 ⫾ 1.2
36 10 42 8 16 34 50
2.9 ⫾ 1.2 2.9 ⫾ 1.0 3.0 ⫾ 1.2 3.1 ⫾ 1.5 2.8 ⫾ 1.2 3.1 ⫾ 1.2 3.0 ⫾ 1.2
3.2 ⫾ 1.3 3.2 ⫾ 1.1 3.3 ⫾ 1.2 3.1 ⫾ 1.5 3.0 ⫾ 1.2 3.4 ⫾ 1.3 3.3 ⫾ 1.2
3.8 ⫾ 1.1 3.4 ⫾ 1.1 3.9 ⫾ 1.0 3.0 ⫾ 1.4 3.6 ⫾ 1.1 3.8 ⫾ 1.2 3.8 ⫾ 1.1
4.0 ⫾ 1.1 3.6 ⫾ 1.1 4.1 ⫾ 0.9 2.9 ⫾ 1.6 3.7 ⫾ 1.1 4.0 ⫾ 1.2 3.9 ⫾ 1.1
4.1 ⫾ 1.0* 3.4 ⫾ 1.1 4.2 ⫾ 0.9** 2.6 ⫾ 1.8 3.8 ⫾ 1.0 4.0 ⫾ 1.3 3.9 ⫾ 1.2
36 10 42 8 16 34 50
4.2 ⫾ 1.0 3.3 ⫾ 1.1 4.1 ⫾ 1.1 3.9 ⫾ 1.1 4.0 ⫾ 1.2 4.1 ⫾ 1.1 4.1 ⫾ 1.1
4.2 ⫾ 1.2 3.4 ⫾ 1.2 4.2 ⫾ 1.2 3.5 ⫾ 1.2 3.8 ⫾ 1.3 4.2 ⫾ 1.1 4.1 ⫾ 1.2
4.7 ⫾ 0.6 3.6 ⫾ 1.2 4.7 ⫾ 0.6 3.4 ⫾ 1.2 4.7 ⫾ 0.6 4.4 ⫾ 1.0 4.5 ⫾ 0.9
4.7 ⫾ 0.5 3.7 ⫾ 1.2 4.7 ⫾ 0.5 3.3 ⫾ 1.3 4.8 ⫾ 0.4 4.4 ⫾ 1.0 4.5 ⫾ 0.9
4.7 ⫾ 0.6** 3.5 ⫾ 1.3 4.7 ⫾ 0.6** 2.8 ⫾ 1.7 4.8 ⫾ 0.4 4.2 ⫾ 1.3 4.4 ⫾ 1.1
36 10 42 8 16 34 50
4.4 ⫾ 1.0 4.5 ⫾ 0.7 4.4 ⫾ 1.0 4.6 ⫾ 0.7 4.5 ⫾ 1.0 4.4 ⫾ 1.0 4.4 ⫾ 1.0
4.5 ⫾ 0.9 4.5 ⫾ 0.7 4.5 ⫾ 0.9 4.5 ⫾ 0.8 4.5 ⫾ 0.8 4.5 ⫾ 0.9 4.5 ⫾ 0.8
4.7 ⫾ 0.7 4.5 ⫾ 0.7 4.7 ⫾ 0.7 4.5 ⫾ 0.8 4.6 ⫾ 0.8 4.7 ⫾ 0.7 4.7 ⫾ 0.7
4.7 ⫾ 0.7 4.4 ⫾ 0.7 4.7 ⫾ 0.7 4.1 ⫾ 0.8 4.6 ⫾ 0.8 4.6 ⫾ 0.7 4.6 ⫾ 0.8
4.7 ⫾ 0.8* 4.2 ⫾ 0.8 4.7 ⫾ 0.7* 3.5 ⫾ 1.6 4.6 ⫾ 0.9 4.5 ⫾ 1.1 4.5 ⫾ 1.0
36 10 42 8 16 34 50
62 ⫾ 16 59 ⫾ 15 62 ⫾ 15 60 ⫾ 17 61 ⫾ 17 63 ⫾ 15 62 ⫾ 15
65 ⫾ 16 62 ⫾ 15 66 ⫾ 16 60 ⫾ 15 62 ⫾ 16 67 ⫾ 15 65 ⫾ 15
73 ⫾ 16 68 ⫾ 16 74 ⫾ 14 58 ⫾ 18 73 ⫾ 16 71 ⫾ 16 71 ⫾ 16
76 ⫾ 15 70 ⫾ 19 78 ⫾ 13 56 ⫾ 18 74 ⫾ 15 74 ⫾ 17 74 ⫾ 16
77 ⫾ 14* 65 ⫾ 22 78 ⫾ 13** 50 ⫾ 19 74 ⫾ 16 73 ⫾ 19 74 ⫾ 18
Abbreviations: Preop. ⫽ preoperatively; Postop. ⫽ postoperatively; * ⫽ p ⬍ 0.05; ** ⫽ p ⬍ 0.01.
1 YEAR
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Multiple Regression Analysis
SIGNIFICANCE RISK FACTOR Male Sex En Plaque Growth Recurrent Tumor Arachnoid Scarring Incomplete Resection Low Spinal Level Anterior Location Young Age Long History Low Preoperative Karnofsky Score
FOR
INCOMPLETE RESECTION
RECURRENCE
LOW POSTOPERATIVE KARNOFSKY SCORE
p ⬍ 0.001 p ⬍ 0.01 p ⬍ 0.01 p ⬍ 0.01 — n.s. p ⬍ 0.01 n.s. n.s. n.s.
n.s. p ⬍ 0.01 n.s. p ⬍ 0.01 p ⬍ 0.01 n.s. n.s. n.s. n.s. n.s.
n.s. n.s. p ⬍ 0.01 n.s. n.s. n.s. p ⬍ 0.05 n.s. n.s. p ⬍ 0.01
Abbreviations: n.s. ⫽ not significant.
year and 40.3% (20.4% for encapsulated and 81.1% for en plaque meningiomas, respectively) after 5 years. Recurrences have been described after decades [8]. This study has clearly demonstrated that a satisfactory postoperative outcome requires complete resection of the spinal meningioma, which could be achieved in 89% of cases [1,10,11,23,26,27,32]. Cauterization or resection of the tumor matrix did not have an influence on recurrence rates [1,23,32]. Whenever complete removal is difficult or even impossible, more than 50% of these patients will experience neurological deterioration within 1 year of surgery. Complications occurred in 11.2% of surger-
ies, which is comparable to figures given in the literature [10,11,14,22,23,27,32]. EN PLAQUE OR INFILTRATING MENINGIOMAS En plaque or infiltrating meningiomas show a different relationship to neighboring structures than encapsulated meningiomas, which displace and compress but respect tissue planes. En plaque growing tumors have a more extensive tumor matrix and infiltrate surrounding structures [34] and may even show ossifications [9]. Similar to encapsulated tumors, the long term outcome was related to the
With complete resection, 29.5% of patients experienced a recurrence within 5 years of surgery whereas all partially removed tumors had recurred by that time (log rank test: p ⫽ 0.0254 after 10 months). No significant difference was observed whether the tumor matrix had been cauterized or resected (26.1% and 31.3% after 5 years, respectively). P describes the probability to remain clinically stable.
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For meningiomas with a well defined capsule, only 20.4% of patients showed a clinical recurrence during follow-up compared to a recurrence rate of 81.1% for en plaque meningiomas (log rank test: p ⫽ 0.0037 after 1 year). P describes the probability to remain clinically stable.
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Klekamp, Samii
extent of resection. Every attempt at complete resection must be made. The tumor matrix should be excised widely whenever possible. However, with infiltration of the pia mater or pronounced arachnoid scarring we consider complete resection without taking unacceptable risks impossible. RECURRENT MENINGIOMAS The worst long term results were associated with recurrent meningiomas. Only 45% could be removed completely. Postoperative neurological scores tended to be lower and 62.1% of them showed progressive neurological symptoms within the first postoperative year. Surgery for a recurrent meningioma has to deal with two pathophysiological mechanisms, each capable of causing progressive neurological deterioration: arachnoid scarring causing spinal cord tethering and the meningioma compressing the spinal cord. Postsurgical arachnoid scarring was found in 90% of these cases [34]. Arachnoid scarring may cause progressive neurological symptoms due to cord tethering, interference with spinal cord blood flow and obstruction of cerebrospinal fluid flow [15,21, 24,35]. Presumably due to this arachnoid scarring, patients with recurrent meningiomas tend to present with severe sensory disturbances, dysesthesias and pain more often than those with primary meningiomas [30]. Similar observations were made with dysraphic malformations and intramedullary tumors [20,31]. Surgery for arachnoid scarring is a very problematic undertaking [21]. Each attempt to resect arachnoid scarring will cause new arachnoid scarring. In order not to aggravate prob-
If arachnoid scarring was present, 67.8% of patients demonstrated a clinical recurrence compared to 31.5% without such arachnoid pathology (log rank test: p ⫽ 0.0013 after 4 months). P describes the probability to remain clinically stable.
7
After a first operation on a spinal meningioma, 30% showed a clinical recurrence within 5 years after surgery. After surgery for a recurrent meningioma, 87.4% recurred within that time (log rank test: p ⫽ 0.0166 after 1 month). P describes the probability to remain clinically stable.
8
lems of cord tethering in the long term, one has to try to limit arachnoid dissection as much as possible to just those steps which are required to untether the cord and allow safe removal of the meningioma. Arachnoid scars should be dissected sharply and with meticulous hemostasis. In such cases we recommend decompressing the subarachnoid space with a dural graft which will provide some protection at least against significant postoperative tethering and cerebrospinal fluid flow obstruction [21,29]. However, arachnoid scarring may also interfere with tumor removal. The arachnoidal sheath covering meningiomas operated for the first time is no longer present in recurrent meningiomas. If intact, this arachnoid not only protects the cord during surgery, it is also a barrier against infiltration of the pia or nerve roots. Thus, the relationship between tumor and surrounding tissues is often altered so that recurrent meningioma often infiltrates neighboring structures [13,30,34,35]. Furthermore, arachnoid scarring may obscure the interface between meningioma, arachnoid and pia mater completely. A multiple regression analysis revealed that a second operation on a meningioma per se was not associated with higher recurrence rates. But infiltrative growth and arachnoid scarring, which could be found in almost every patient with a recurrent meningioma, were independent factors associated with postoperative neurological deterioration. Therefore, the first surgeon to operate on a spinal meningioma is in a position of great responsibility.
Spinal Meningiomas
He has the best opportunity to provide a cure for the patient. Once the first attempt has failed and the tumor recurs, it will be very difficult to achieve a satisfactory long-term result.
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13.
14.
Conclusions 15.
1. Complete resection of a spinal meningioma should be attempted in every case. With complete resection, long-term prognosis is excellent. 2. Surgery should be followed by rehabilitation programs even for patients in advanced age. Recovery of neurological deficits can almost always be expected. 3. En plaque and infiltrative meningiomas should be seen as a separate entity. They remain surgical challenges due to their extensive tumor matrix and infiltrative nature. 4. Arachnoid scarring and cord tethering may pose additional problems, particularly in surgery for recurrent meningiomas, and has to be dealt with intraoperatively as well. A dural graft seems to offer reasonable protection against retethering.
16. 17.
18. 19. 20. 21.
REFERENCES 1. Boccardo M, Ruelle A, Mariotti E. Personal experience with the surgery of spinal meningiomas. Ital J Neurol Sci 1985;6:29 –35. 2. Bret P, Lecuire J, Lapras C, Deruty R, Dechaume JP, Arsaad A. Les meningiomas intra-rachidiens. Reflexions apropos d’une serie de 60 observations. Neurochirurgie 1976;22:5–22. 3. Bull JWD. Spinal meningiomas and neurofibromas. Acta Radiol 1953;40:283–300. 4. Chern SH, Lin SM, Tseng SH, Tu YK, Yang LS, Kao MC, Hung CC. Prognostic factors of intraspinal neurilemmoma and meningioma with severe preoperative motor deficits. J Formos Med Assoc 1993;92:227–30. 5. Ciapetta P, Domenicucci M, Raco A. Spinal meningiomas: prognosis and recovery factors in 22 cases with severe motor deficits. Acta Neurol Scand 1988;77:27– 30. 6. Cushing H, Eisenhardt L. Meningiomas. Their classification, regional behaviour, life history, and surgical end results. Springfield, Illinois: C.C. Thomas, 1938. 7. Davis RA, Washburn PL. Spinal cord meningioma. Surg Gynecol Obstet 1970;131:15–21. 8. Feiring EH, Barron K. Late recurrence of spinal cord meningioma. J Neurosurg 1962;19:652– 6. 9. Freidberg SR. Removal of an ossified ventral thoracic meningioma. Case report. J Neurosurg 1972;37:728 – 30. 10. Goldhahn WE, Schmidt U. Das spinale Meningiom. Zentralbl Neurochir 1989;50:18 –23. 11. Gra¨we A, Siedschlag WD, Nisch G, Schulz MR. Meningiome des Spinalkanals. Klinik und Langzeitergebnisse. Zentralbl Neurochir 1986;47:139 – 43. 12. Griffiths IR. Vasogenic edema following acute and
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chronic spinal cord compression in the dog. J Neurosurg 1975;42:155– 65. Horrax G, Poppen JL, Wu WR, Weadon PR. Meningiomas and neurofibromas of the spinal cord. Certain clinical features and end results. Surg Clin N Am 1949; 29:659 – 65. Iraci G, Peserico L, Salar G. Intraspinal neurinomas and meningiomas. A clinical survey of 172 cases. Int Surg 1971;56:289 –303. Kang JK, Kim MC, Kim DS, Song JV. Effects of tethering on regional and spinal cord blood flow and sensory evoked potentials in growing cats. Child’s Nerv Syst 1987;3:35–9. Kaplan EL, Meier P. Nonparametric estimation from incomplete observations. J Am Stat Assoc 1958;53: 457– 81. Karnofsky DA, Burchenal JH. The clinical evaluation of chemotherapeutic agents in cancer. In: MacLeod CM, ed. Evaluation of chemtherapeutic agents. New York; Columbia University Press, 1949:191–205. Katz K, Reichental E, Israeli J. Surgical treatment of spinal meningiomas. Neurochirurgia 1981;24:21–2. Klekamp J, Samii M. Introduction of a score system for the clinical evaluation of patients with spinal processes. Acta Neurochir 1993;123:221–3. Klekamp J, Raimondi AJ, Samii M. Occult dysraphism in adulthood: clinical course and management. Child’s Nerv Syst 1994;10:312–20. Klekamp J, Batzdorf U, Samii M, Bothe HW. Treatment of syringomyelia associated with arachnoid scarring caused by arachnoiditis or trauma. J Neurosurg 1997; 86:233– 40. Kunicki A, Maciejak A. Results of operative treatment in 154 cases of extramedullary meningiomas and neurinomas. Acta Medica Pol 1965;6:397– 404. Levy WJ Jr, Bay J, Dohn D. Spinal cord meningioma. J Neurosurg 1982;57:804 –12. Mackay R. Chronic adhesive spinal arachnoiditis. A clinical and pathologic study. JAMA 1939;112:802– 808. McCormick PC, Post KD, Stein BM. Intradural extramedullary tumors in adults. In: Stein BM, McCormick PC eds. Neurosurgery Clinics of North America. Vol 1 no 3. Intradural Spinal surgery. Philadelphia: W.B. Saunders, 1990:591– 608. Mirimanoff RO, Dosoretz DE, Lingood RM, Ojemann RG, Martuza RL. Meningioma: analysis of recurrence and progression following neurosurgical resection. J Neurosurg 1985;62:18 –24. Namer IJ, Pamir MN, Benli K, Saglam S, Erbengi A. Spinal meningiomas. Neurochirurgia 1987;30:11–5. Nittner K. Spinal meningiomas, neurinomas and neurofibromas. In: Vinken PJ, Bruyn GW eds. Handbook of Clinical Neurology. Vol. 20. Tumours of the Spine and Spinal Cord. Part II. Amsterdam: North Holland, 1976:177–322. Onofrio BM. Intradural extramedullary spinal cord tumors. Clin Neurosurg 1978;25:540 –55. Rogers L. Tumors involving the spinal cord and its nerve roots. Ann R Coll Surg Engl 1955;16:1–29. Samii M, Klekamp J. Surgical results of 100 intramedullary tumors in relation to accompanying syringomyelia. Neurosurgery 1994;35:865–73. Solero CL, Fornari M, Giombini S, Lasio G, Oliveri G,
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Cimino C, Pluchino F. Spinal meningioma: review of 174 operated cases. Neurosurgery 1989;25:153– 60. Souweidane MN, Benjamin V. Spinal cord meningiomas. Neurosurg Clin N Am 1994;5:283–91. Stechison MT, Tasker RR, Wortzman G. Spinal meningioma en plaque. Report of two cases. J Neurosurg 1987;67:452–55. Vloeberghs M, Herregodts P, Stadnik T, Goossens A, D’Haens J. Spinal arachnoiditis mimicking a spinal cord tumor: a case report and review of the literature. Surg Neurol 1992;37:211–5. Wenker H, Reuter F. Spinal tumours: a multicenter study of the Deutsche Gesellschaft fu ¨ r Neurochirurgie. Adv Neurosurg 1986;14:81–95.
COMMENTARY
This retrospective study carefully documents the clinical features and outcomes in a large surgical series of patients with spinal meningiomas managed at a single institution over a long time period. While the absolute numbers and percentages reported in this study probably reflect a substantial referral and treatment bias, there are a number of noteworthy observations. First, most patients do well after gross total resection of well-circumscribed spinal meningiomas, even those with significant neurologic deficits at presentation. Secondly, the recurrence rate in this subset of tumors seems to be independent of management of the dural attachment (i.e., resect and patch vs. coagulate). Thirdly,
as in most other instances of benign extramedullary tumors, gross total resection at the first operation offers the best opportunity for long-term tumor control or cure. Finally, infiltrative or en plaque meningiomas present a considerable surgical challenge. The recurrence rate and potential for significant neurologic morbidity either during primary removal or surgery for recurrence are significant. Paul C. McCormick, M.D. Neurological Surgery Columbia–Presbyterian Medical Center New York, New York, USA There are some interesting findings in this review. I was surprised to learn that 14.7% of the patients with spinal meningioma had a recurrence, and that the overall recurrence rate was calculated to be 21% at one year and 40.3% at 5 years. Without reviewing our data, I would have guessed that the rate would be much lower. Clearly, a surgeon must be cautious about the prognosis in cases of spinal meningioma, especially if the tumor is en plaque or has recurred. Russel H. Patterson, Jr., M.D. Neurosurgeon New York, New York, USA
he world of 2025 can be broken down into three broad population groups: World 1, including the affluent advanced nations of Europe, the United States, and Japan; World 2, the middle, making up the bulk of the world’s population, whose immediate needs and resources will be in relative balance; and World 3, the destitute nations, those on the brink of starvation, living with the constant threat of disaster.
T
—Joseph Coates, John Mahaffie, and Andy Hines “2025: Scenarios of US and Global Society Reshaped by Science and Technology” (1997)
Klekamp J, Samii M. Surgical results for spinal meningiomas. Surg Neurol 1999;52:552– 62.
Among a series of 782 spinal tumors, 130 spinal meningiomas in 117 patients were operated in the Department of Neurosurgery at the Nordstadt Hospital in Hannover, Germany, between 1977 and 1998. Patients were followed postoperatively for up to 13 years (mean 20 ⫾ 33 months). Comparing the period of 1977 through 1987, before magnetic resonance imaging (MRI) was available, to the period of 1988 to 1998 revealed that the average history until diagnosis shortened by about 6 months during the second decade of this study (24 ⫾ 33 to 18 ⫾ 29 months; not significant). Consequently, the preoperative Karnofsky Score increased significantly (59 ⫾ 15 and 66 ⫾ 16; p ⬍ 0.05). The rates of complete resection and the postoperative neurological outcome, however, remained unchanged. Even though the overall prognosis of neurological deficits is favorable after complete resection of a meningioma, a subset of 18 patients had either en plaque growing or recurrent tumors that were more likely to be removed incompletely and to cause postoperative neurological problems, with a significantly worse Karnofsky Score after 1 year (57 ⫾ 12 and 77 ⫾ 12, respectively; p ⬍ 0.01) and a significantly higher recurrence rate after 5 years (86.7% and 20.4%, respectively; log rank test p ⫽ 0.0014). In conclusion, a favorable postoperative neurological outcome requires complete resection of the spinal meningioma. The advent of MRI has shortened the time until diagnosis and made it possible to perform surgery before severe deficits have occurred, but did not have a major impact on postoperative results. En plaque and recurrent meningiomas remain surgical challenges, as infiltration of surrounding structures and associated arachnoid scarring may render complete resection difficult to achieve. © 1999 by Elsevier Science Inc. KEY WORDS
Arachnoiditis, spinal neoplasms.
t is well established that spinal meningiomas carry an excellent prognosis in general [1,2,4 –7, 10,11,14,18,22,23,25,27,29,32,33]. However, a number of factors such as arachnoid scarring associ-
I
Address reprint requests to: Dr. Klekamp, Nordstadt Hospital, Neurosurgical Clinic, Haltenhoffstr.41, D-30167 Hannover, Germany. Received November 29, 1995; accepted August 11, 1999. 0090-3019/99/$–see front matter PII S0090-3019(99)00153-6
ated with recurrent tumors, the growth pattern of the tumor, and the influence of magnetic resonance imaging (MRI) have not been evaluated. This study will analyze the impact of these factors on diagnosis, surgical strategy and postoperative outcome.
Material and Methods During the period between 1977 and 1998, a total of 782 spinal tumors were operated in our department. Among these, 130 meningiomas in 117 patients were removed. Case records, operative reports, follow-up information, and neuroradiological findings were evaluated. Additional data were obtained by questionnaires or telephone calls. The clinical course was documented using the Karnofsky Score [17] and a score system for each symptom [19] (Table 1). In general, scores between 3 and 5 describe satisfactory levels of function and scores between 0 and 2 indicate unsatisfactory or incapacitated functions. For analysis of sensory function or motor power only the most affected part of the body was evaluated. Preoperative imaging consisted of plain X-rays of the affected spinal segments and a myelogram with postmyelographic computed tomography (CT) before MRI was available. This period lasted from 1977 to 1987. Since 1988, MRI has replaced myelography and CT and is the imaging modality of choice. Surgery consisted of a laminectomy or laminotomy with intraoperative fluoroscopic control. Depending on the dural attachment (⫽ tumor matrix), a facet joint or the proximal part of a rib were resected to gain access to anterior tumors. After dural opening care was taken to preserve the arachnoidal sheath at the interface between tumor and spinal cord to protect the cord and its blood supply. Posteriorly placed tumors were generally removed in toto including the dural attachment (Figure 1). The dural defect was closed with a duraplasty. For anterior or lateral meningiomas, the tumor was © 1999 by Elsevier Science Inc. 655 Avenue of the Americas, New York, NY 10010
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1
Neurological Scoring System
SCORE 5 4 3 2 1 0
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SENSORY DEFICITS, PAIN, DYSESTHESIAS
MOTOR WEAKNESS
GAIT ATAXIA
No Symptom Present, Not Significant Significant, Function Not Restricted Some Restriction Of Function Severe Restriction Of Function Incapacitated
Full Power Movement Against Resistance Movement Against Gravity Movement Without Gravity Contraction Without Plegia
Normal Unsteady No Aid Mobile With Aid
BLADDER FUNCTION Normal Slight Dist., No Catheter Residual, No Cath.
BOWEL FUNCTION Normal Slight Dist., Full Control Laxatives, Full Control
Few Steps With Aid Sometimes Catheter Sometimes Loss Of Control Standing With Aid Often Catheter Often Loss Of Control Wheel Chair
Permanent Catheter No Control
Abbreviations: Dist. ⫽ disturbance; Cath. ⫽ catheter.
debulked first and then the capsule was dissected free and removed. The dural attachment was either coagulated or the inner dural layer was resected (Figure 2). With recurrent meningiomas such an arachnoidal interface was not present in most instances. Consequently, the attachment of the tumor to neighboring structures was tighter. Nerve roots and vessels were often encased and sometimes even the pia mater was infiltrated. Likewise, en plaque growing tumors were devoid of a capsule and tended to infiltrate surrounding structures (Figure 3). The tumor matrix tended to be more extensive. Using microsurgical techniques, these tumors were debulked first. The tumor mass could be resected completely except in cases of meningiomas with pia infiltration. With recurrent meningiomas, severe arachnoid scarring sometimes made it impossible
to clearly distinguish between scar, meningioma, and cord. Especially with anterior extension of such a tumor, it was our policy to leave a small amount of tumor in place rather than risk permanent neurological deficits. Postoperatively, every patient received plain X-rays and—since the advent of MRI—a gadolinium enhanced MRI scan after 3 months. Further scans were performed if the clinical situation deteriorated or if the tumor removal had been incomplete. Postoperative clinical examinations were performed at discharge and after 3 months. Additional follow-up information was obtained by further outpatient examinations, telephone calls or questionnaires.
Posterior en plaque meningioma in a 71-year-old patient with sensory deficits, dysesthesias, motor weakness, and gait ataxia. The tumor was removed completely including the dural attachment. The patient recovered completely and is without recurrence 2 years postoperatively.
Anterior meningioma at C2 in a 62-year-old woman with neck pain, gait ataxia, motor weakness, and sensory deficits. The tumor was removed completely with cauterization of the tumor matrix. The patient made a complete recovery and is without a recurrence 3 years postoperatively.
1
2
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Pre- (A, B) and postoperative (C) MRI scans with gadolinium in a 68-year-old woman with a recurrent en plaque growing meningioma at the cervicothoracic junction. The tumor had infiltrated the dura and leptomeninges, encircling the cord completely. Part of the tumor was calcified. The meningioma was removed partially and a fascia lata graft was inserted to decompress the subarachnoid space. Postoperatively, the patient remained neurologically stable. However, severe dysesthesias and spasms in her lower extremities continue to prevent mobilization, rendering her confined to a wheelchair.
3
The postoperative course was analyzed according to the symptom scores outlined above and by determining the percentage of patients who experi-
enced progressive neurological deterioration postoperatively using Kaplan-Meier statistics [16]. Such clinical progression was either due to recurrent
Spinal Meningiomas
tumor or delayed postoperative morbidity related to arachnoid scarring, syringomyelia or instability, and myelopathy. Means are presented plus/minus the standard deviation. For statistical analyses Student’s t test for paired or unpaired variables and the chi-square test were used provided the Komolgorov– Smirnov test indicated normal data distribution. Statistical differences for rates of neurological progression were determined using the log rank test. A difference was considered significant if a p-value of 0.05 was reached.
Results CLINICAL DATA During the study period 117 patients were operated for 130 spinal meningiomas. The average age was 57 ⫾ 15 years (range 17 to 86 years). Female sex predominated by a factor of 3.9:1 (24 males and 93 females). The average history until admission for surgery was 19 ⫾ 30 months. The majority of patients presented a slowly progressive course which started with pain or dysesthesias in 50% of all patients. Twenty-two percent noticed gait problems as the first symptom, 16% motor weakness, and 12% sphincter disturbances or sensory deficits. In one particular case, the history dated back for 18 years before the diagnosis was made. Since the advent of MRI in our institution in 1988, we observed a shortening of the average preoperative history by about 6 months (24 ⫾ 33 months and 18 ⫾ 29 months, respectively; not significant). For recurrent meningiomas, the diagnosis was reached significantly earlier compared to patients without a history of a previous neurosurgical intervention (13 ⫾ 18 months and 21 ⫾ 31 months, respectively; p ⬍ 0.05). Likewise, the history of en plaque growing tumors was shorter compared to encapsulated meningiomas (11 ⫾ 10 months and 22 ⫾ 33 months, respectively; p ⬍ 0.01). SYMPTOMS AND SIGNS ON ADMISSION On admission, 59% demonstrated gait ataxia as the predominating neurological symptom. Twenty percent complained of pain, 16% of motor weakness, 5% of dysesthesias, and 1% of sensory deficits as the major clinical problem. Since the advent of MRI, patients were referred earlier and with less severe neurological deficits than previously. Preoperative scores for motor power (2.8 ⫾ 1.2 and 3.4 ⫾ 1.2, respectively; p ⬍ 0.01) and gait (2.8 ⫾ 1.1 and 3.2 ⫾ 1.3, respectively; p ⬍ 0.05) increased significantly
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and the average preoperative Karnofsky Score improved from 59 ⫾ 17 to 66 ⫾ 16 (p ⬍ 0.05). SURGICAL FINDINGS Twenty-seven percent of all meningiomas were found in the cervical, 67% in the thoracic, and 6% in the lumbosacral spine. The tumor matrix was posterior in 28%, anterior in 27%, and lateral in 45% of all cases. Ten meningiomas (8%) demonstrated extradural extension (Figure 4). Although 103 meningiomas presented a well-defined capsule displacing surrounding structures, 27 were devoid of a capsule and infiltrated nerve roots, pia mater, dura mater and/or bone. One of these meningiomas showed ossifications (Figure 3). Twenty operations dealt with recurrent meningiomas. Only 7 of these recurrent tumors presented a tumor capsule; 13 did not (chi-square test: p ⬍ 0.0001). Compared to 11% of primary operated meningiomas, 90% of recurrent meningiomas were associated with arachnoid scarring or adhesions causing additional cord tethering (chi-square test: p ⬍ 0.0001). Compared to 14% of encapsulated meningiomas, this finding was also more prominent for en plaque growing meningiomas (chi-square test: p ⫽ 0.0005). SURGICAL RESULTS Complete resections were achieved for 115 (89%) meningiomas. We did not observe a difference comparing the early cases before 1988 to those thereafter (89% and 88%, respectively). However, different rates of complete resections were seen according to growth pattern (97% of encapsulated and 53% of en plaque meningiomas, respectively; chi-square test: p ⬍ 0.0001), number of previous surgeries (95% for first operations and 45% for recurrent tumors; chi-square test: p ⬍ 0.0001), and additional arachnoid scarring (94% without arachnoid scarring and 70% with additional scarring, respectively; chi-square test: p ⫽ 0.0013). Complications occurred in 11.2% of surgeries (Table 2). Two patients died during their postoperative hospital stay within 30 days from aspiration pneumonia and myocardial infarction (surgical mortality 1.5%), and an additional 4 patients died during the first postoperative year due to cardiac and respiratory problems unrelated to the spinal meningioma. NEUROLOGICAL OUTCOME Patients were followed for up to 13 years (20 ⫾ 33 months). In general, the prognosis for neurological recovery is excellent. Of 31 patients unable to walk preoperatively, 29% could walk before discharge from hospital. Within 3 months of rehabilitation this figure rose to 57% and after 1 year, 80% were again
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Lateral meningioma with extradural extension in a 67-year-old patient with gait ataxia, motor weakness, sensory deficits, and dysesthesias. The tumor was removed completely with resection of the dura. Postoperatively, the patient made a complete recovery.
4
able to walk independently. Due to this excellent neurological recovery, no significant difference in outcome was observed between patients operated between 1977 and 1987 and those operated since 1988, although a tendency toward faster recovery of function was seen in the second decade, presum-
ably due to earlier diagnosis. Table 3 gives an overview of postoperative neurological scores for the first postoperative year. For encapsulated meningiomas and meningiomas operated on for the first time, every neurological score improved during the first postoperative year. Twelve percent of these
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2
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Complications
TYPE OF COMPLICATION Infection Aseptic Meningitis CSF Leak, Pseudomeningocele Hemorrhage Instability Aspiration Pneumonia Urinary Tract Infection Myocardial Infarction Postoperative Permanent Deficit Total
ENCAPSULATED
EN PLAQUE
1 1 2
— — 3
1 1 1 1 1 —
— — — — — 1
9
4
patients experienced a transient postoperative worsening of neurological symptoms, which recovered within 6 months. For infiltrative or recurrent meningiomas only 5% showed a transient neurological deterioration, due to the less aggressive surgical strategy for these patients. A permanent neurological deficit was observed in only one patient with an infiltrative meningioma. However, this low figure for surgical morbidity was associated with significantly worse postoperative neurological scores after one year for almost all symptoms and Karnofsky Scores (Table 3). If a complete resection was achieved, postoperative neurological scores and Karnofsky Scores were similar to those for encapsulated meningiomas. RECURRENCE RATES The overall recurrence rates for spinal meningiomas as calculated by the Kaplan–Meier method were 21% after one year and 40.3% after 5 years. A multiple regression analysis revealed that significantly higher recurrence rates have to be expected with en plaque or infiltrating meningiomas, tumors associated with arachnoid scarring, and after partial resections (Table 4). We saw higher recurrence rates for infiltrative tumors compared to encapsulated meningiomas after 1 year (49.5% and 7.9%, respectively; log rank test: p ⫽ 0.0037) and after 5 years (81.1% and 20.4%, respectively, log rank test: p ⫽ 0.0004) (Figure 5). After complete or partial resection, the corresponding figures were 14.6% and 52% after 1 year (log rank test: p ⫽ 0.0117) and 29.5% and 100% after 5 years (log rank test: p ⫽ 0.0011) (Figure 6). There was no statistical difference between patients in whom the tumor matrix was coagulated or resected (18.8% and 13.4% after 1 year, respectively; 26.1% and 31.3% after 5 years, respectively; log rank test: not significant) (Figure
6). For meningiomas associated with arachnoid scarring, we observed significantly higher clinical recurrence rates compared to meningiomas without such arachnoid changes (51.7% and 11.2% after one year, respectively; log rank test: p ⫽ 0.0002; 67.8% and 31.5% after 5 years, respectively; log rank test: p ⫽ 0.0003) (Figure 7). Comparing first surgeries and recurrent meningiomas, recurrence rates were 12.5% and 62.1% after one year (log rank test: p ⬍ 0.0001), and 30% and 87.4% after 5 years, respectively (log rank test: p ⬍ 0.0001) (Figure 8).
Discussion This retrospective study on spinal meningiomas revealed that MRI has led to earlier diagnosis of these tumors, shortened the preoperative history and thus improved the preoperative neurological status of these patients who can now be operated before severe deficits have occurred. We also identified a subset of patients whose tumors were more difficult to remove and who recover less well postoperatively and are more prone to experience recurrences. The demographics of patients with spinal meningiomas have been described extensively in previous reports [1–7,10,11,13,14,18,22,23,25–29,32,33, 36]. Even though the diagnosis has been made easier with MRI nowadays, the postoperative outcome of patients with spinal meningiomas has not improved significantly in the last decade. However, even in patients with severe preoperative neurological deficits complete resection of spinal meningiomas is followed by full neurological recovery in most instances with appropriate rehabilitation [1,2, 4 –7,10,11,13,14,18,22,23,25,27,29,32,33]. Transient neurological worsening may occur due to dissection [5] or vasogenic edema [12], but recovers within 6 months. Therefore, compared to patients treated before 1987, only a tendency toward faster neurological recovery was observed in patients operated in the second decade of this study. The figures for recurrence rates given in this study may seem higher than those reported in the literature with 6% [32] and 10 to 15% [25]. However, these studies did not use Kaplan–Meier statistics that account for varying follow-up times. Therefore, these numbers grossly underestimate the rate of patients who will have a recurrence after several years. In total, 14.7% of our patients demonstrated a recurrence— 6.9% of those with encapsulated meningiomas and 36.8% of patients with en plaque meningiomas. These figures correspond to recurrence rates of 21% (7.9% for encapsulated and 49.5% for en plaque meningiomas, respectively) after 1
558 Surg Neurol 1999;52:552–62
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Klekamp, Samii
Clinical Course of Patients with Spinal Meningiomas
GROUP/SYMPTOM Pain Encapsulated En plaque First Surgery Recurrent Tumor 1977–1987 1988–1998 Total Dysesthesias Encapsulated En plaque First Surgery Recurrent Tumor 1977–1987 1988–1998 Total Sensory Deficits Encapsulated En plaque First Surgery Recurrent Tumor 1977–1987 1988–1998 Total Motor Weakness Encapsulated En plaque First Surgery Recurrent Tumor 1977–1987 1988–1998 Total Gait Encapsulated En plaque First Surgery Recurrent Tumor 1977–1987 1988–1998 Total Bladder Function Encapsulated En plaque First Surgery Recurrent Tumor 1977–1987 1988–1998 Total Bowel Function Encapsulated En plaque First Surgery Recurrent Tumor 1977–1987 1988–1998 Total Karnofsky Score Encapsulated En plaque First Surgery Recurrent Tumor 1977–1987 1988–1998 Total
N
PREOP.
POSTOP.
3 MONTHS
6 MONTHS
36 10 42 8 16 34 50
3.4 ⫾ 1.1 3.0 ⫾ 1.3 3.4 ⫾ 1.1 3.0 ⫾ 1.5 3.5 ⫾ 1.1 3.2 ⫾ 1.2 3.3 ⫾ 1.2
4.0 ⫾ 0.7 3.8 ⫾ 0.9 4.0 ⫾ 0.7 3.4 ⫾ 0.7 3.8 ⫾ 0.8 4.0 ⫾ 0.8 3.9 ⫾ 0.8
4.4 ⫾ 0.6 4.0 ⫾ 1.1 4.4 ⫾ 0.6 3.4 ⫾ 0.9 4.3 ⫾ 0.7 4.2 ⫾ 0.8 4.3 ⫾ 0.8
4.4 ⫾ 0.6 3.9 ⫾ 1.2 4.5 ⫾ 0.6 3.3 ⫾ 1.0 4.3 ⫾ 0.7 4.3 ⫾ 0.9 4.3 ⫾ 0.8
4.4 ⫾ 0.7 3.4 ⫾ 1.8 4.4 ⫾ 0.7** 2.8 ⫾ 1.6 4.3 ⫾ 0.8 4.1 ⫾ 1.2 4.2 ⫾ 1.1
36 10 42 8 16 34 50
3.8 ⫾ 1.1 3.9 ⫾ 1.4 3.9 ⫾ 1.0 3.5 ⫾ 1.3 4.1 ⫾ 1.1 3.8 ⫾ 1.1 3.9 ⫾ 1.1
4.3 ⫾ 0.8 4.4 ⫾ 0.8 4.4 ⫾ 0.8 4.1 ⫾ 0.8 4.4 ⫾ 0.8 4.3 ⫾ 0.8 4.3 ⫾ 0.8
4.5 ⫾ 0.6 4.3 ⫾ 0.8 4.5 ⫾ 0.6 4.1 ⫾ 0.8 4.6 ⫾ 0.5 4.4 ⫾ 0.7 4.5 ⫾ 0.7
4.6 ⫾ 0.6 4.1 ⫾ 1.1 4.6 ⫾ 0.6 3.9 ⫾ 1.1 4.6 ⫾ 0.5 4.4 ⫾ 0.8 4.5 ⫾ 0.7
4.6 ⫾ 0.6* 3.5 ⫾ 1.4 4.5 ⫾ 0.6* 3.4 ⫾ 1.5 4.6 ⫾ 0.6 4.2 ⫾ 1.0 4.4 ⫾ 0.9
36 10 42 8 16 34 50
3.1 ⫾ 0.9 2.4 ⫾ 1.6 3.1 ⫾ 0.8 2.1 ⫾ 1.7 2.9 ⫾ 1.0 3.0 ⫾ 1.1 3.0 ⫾ 1.0
3.7 ⫾ 1.0 2.6 ⫾ 1.8 3.7 ⫾ 0.9 2.1 ⫾ 2.0 3.1 ⫾ 1.4 3.6 ⫾ 1.2 3.4 ⫾ 1.4
4.1 ⫾ 1.0 2.8 ⫾ 2.0 4.0 ⫾ 0.9 2.3 ⫾ 2.1 3.6 ⫾ 1.4 3.9 ⫾ 1.3 3.8 ⫾ 1.3
4.1 ⫾ 1.0 2.9 ⫾ 2.1 4.1 ⫾ 1.0 2.1 ⫾ 2.1 3.8 ⫾ 1.5 3.9 ⫾ 1.4 3.8 ⫾ 1.4
4.2 ⫾ 1.1* 2.8 ⫾ 2.1 4.2 ⫾ 1.0** 2.0 ⫾ 2.1 3.8 ⫾ 1.5 3.9 ⫾ 1.4 3.8 ⫾ 1.4
36 10 42 8 16 34 50
2.9 ⫾ 1.1 3.1 ⫾ 1.4 3.0 ⫾ 1.1 3.3 ⫾ 1.5 2.8 ⫾ 1.4 3.2 ⫾ 1.1 3.1 ⫾ 1.2
3.4 ⫾ 1.1 3.4 ⫾ 1.2 3.6 ⫾ 1.1 3.3 ⫾ 1.5 3.2 ⫾ 1.1 3.7 ⫾ 1.1 3.5 ⫾ 1.1
3.9 ⫾ 1.0 3.8 ⫾ 1.0 4.0 ⫾ 0.9 3.3 ⫾ 1.4 3.7 ⫾ 1.1 4.0 ⫾ 1.0 3.9 ⫾ 1.0
4.2 ⫾ 1.0 3.9 ⫾ 1.1 4.4 ⫾ 0.8 3.1 ⫾ 1.5 3.9 ⫾ 1.0 4.3 ⫾ 1.0 4.2 ⫾ 1.0
4.3 ⫾ 0.9* 3.6 ⫾ 1.3 4.4 ⫾ 0.8* 2.6 ⫾ 1.8 4.0 ⫾ 1.1 4.2 ⫾ 1.2 4.1 ⫾ 1.2
36 10 42 8 16 34 50
2.9 ⫾ 1.2 2.9 ⫾ 1.0 3.0 ⫾ 1.2 3.1 ⫾ 1.5 2.8 ⫾ 1.2 3.1 ⫾ 1.2 3.0 ⫾ 1.2
3.2 ⫾ 1.3 3.2 ⫾ 1.1 3.3 ⫾ 1.2 3.1 ⫾ 1.5 3.0 ⫾ 1.2 3.4 ⫾ 1.3 3.3 ⫾ 1.2
3.8 ⫾ 1.1 3.4 ⫾ 1.1 3.9 ⫾ 1.0 3.0 ⫾ 1.4 3.6 ⫾ 1.1 3.8 ⫾ 1.2 3.8 ⫾ 1.1
4.0 ⫾ 1.1 3.6 ⫾ 1.1 4.1 ⫾ 0.9 2.9 ⫾ 1.6 3.7 ⫾ 1.1 4.0 ⫾ 1.2 3.9 ⫾ 1.1
4.1 ⫾ 1.0* 3.4 ⫾ 1.1 4.2 ⫾ 0.9** 2.6 ⫾ 1.8 3.8 ⫾ 1.0 4.0 ⫾ 1.3 3.9 ⫾ 1.2
36 10 42 8 16 34 50
4.2 ⫾ 1.0 3.3 ⫾ 1.1 4.1 ⫾ 1.1 3.9 ⫾ 1.1 4.0 ⫾ 1.2 4.1 ⫾ 1.1 4.1 ⫾ 1.1
4.2 ⫾ 1.2 3.4 ⫾ 1.2 4.2 ⫾ 1.2 3.5 ⫾ 1.2 3.8 ⫾ 1.3 4.2 ⫾ 1.1 4.1 ⫾ 1.2
4.7 ⫾ 0.6 3.6 ⫾ 1.2 4.7 ⫾ 0.6 3.4 ⫾ 1.2 4.7 ⫾ 0.6 4.4 ⫾ 1.0 4.5 ⫾ 0.9
4.7 ⫾ 0.5 3.7 ⫾ 1.2 4.7 ⫾ 0.5 3.3 ⫾ 1.3 4.8 ⫾ 0.4 4.4 ⫾ 1.0 4.5 ⫾ 0.9
4.7 ⫾ 0.6** 3.5 ⫾ 1.3 4.7 ⫾ 0.6** 2.8 ⫾ 1.7 4.8 ⫾ 0.4 4.2 ⫾ 1.3 4.4 ⫾ 1.1
36 10 42 8 16 34 50
4.4 ⫾ 1.0 4.5 ⫾ 0.7 4.4 ⫾ 1.0 4.6 ⫾ 0.7 4.5 ⫾ 1.0 4.4 ⫾ 1.0 4.4 ⫾ 1.0
4.5 ⫾ 0.9 4.5 ⫾ 0.7 4.5 ⫾ 0.9 4.5 ⫾ 0.8 4.5 ⫾ 0.8 4.5 ⫾ 0.9 4.5 ⫾ 0.8
4.7 ⫾ 0.7 4.5 ⫾ 0.7 4.7 ⫾ 0.7 4.5 ⫾ 0.8 4.6 ⫾ 0.8 4.7 ⫾ 0.7 4.7 ⫾ 0.7
4.7 ⫾ 0.7 4.4 ⫾ 0.7 4.7 ⫾ 0.7 4.1 ⫾ 0.8 4.6 ⫾ 0.8 4.6 ⫾ 0.7 4.6 ⫾ 0.8
4.7 ⫾ 0.8* 4.2 ⫾ 0.8 4.7 ⫾ 0.7* 3.5 ⫾ 1.6 4.6 ⫾ 0.9 4.5 ⫾ 1.1 4.5 ⫾ 1.0
36 10 42 8 16 34 50
62 ⫾ 16 59 ⫾ 15 62 ⫾ 15 60 ⫾ 17 61 ⫾ 17 63 ⫾ 15 62 ⫾ 15
65 ⫾ 16 62 ⫾ 15 66 ⫾ 16 60 ⫾ 15 62 ⫾ 16 67 ⫾ 15 65 ⫾ 15
73 ⫾ 16 68 ⫾ 16 74 ⫾ 14 58 ⫾ 18 73 ⫾ 16 71 ⫾ 16 71 ⫾ 16
76 ⫾ 15 70 ⫾ 19 78 ⫾ 13 56 ⫾ 18 74 ⫾ 15 74 ⫾ 17 74 ⫾ 16
77 ⫾ 14* 65 ⫾ 22 78 ⫾ 13** 50 ⫾ 19 74 ⫾ 16 73 ⫾ 19 74 ⫾ 18
Abbreviations: Preop. ⫽ preoperatively; Postop. ⫽ postoperatively; * ⫽ p ⬍ 0.05; ** ⫽ p ⬍ 0.01.
1 YEAR
Spinal Meningiomas
4
Surg Neurol 559 1999;52:552–62
Multiple Regression Analysis
SIGNIFICANCE RISK FACTOR Male Sex En Plaque Growth Recurrent Tumor Arachnoid Scarring Incomplete Resection Low Spinal Level Anterior Location Young Age Long History Low Preoperative Karnofsky Score
FOR
INCOMPLETE RESECTION
RECURRENCE
LOW POSTOPERATIVE KARNOFSKY SCORE
p ⬍ 0.001 p ⬍ 0.01 p ⬍ 0.01 p ⬍ 0.01 — n.s. p ⬍ 0.01 n.s. n.s. n.s.
n.s. p ⬍ 0.01 n.s. p ⬍ 0.01 p ⬍ 0.01 n.s. n.s. n.s. n.s. n.s.
n.s. n.s. p ⬍ 0.01 n.s. n.s. n.s. p ⬍ 0.05 n.s. n.s. p ⬍ 0.01
Abbreviations: n.s. ⫽ not significant.
year and 40.3% (20.4% for encapsulated and 81.1% for en plaque meningiomas, respectively) after 5 years. Recurrences have been described after decades [8]. This study has clearly demonstrated that a satisfactory postoperative outcome requires complete resection of the spinal meningioma, which could be achieved in 89% of cases [1,10,11,23,26,27,32]. Cauterization or resection of the tumor matrix did not have an influence on recurrence rates [1,23,32]. Whenever complete removal is difficult or even impossible, more than 50% of these patients will experience neurological deterioration within 1 year of surgery. Complications occurred in 11.2% of surger-
ies, which is comparable to figures given in the literature [10,11,14,22,23,27,32]. EN PLAQUE OR INFILTRATING MENINGIOMAS En plaque or infiltrating meningiomas show a different relationship to neighboring structures than encapsulated meningiomas, which displace and compress but respect tissue planes. En plaque growing tumors have a more extensive tumor matrix and infiltrate surrounding structures [34] and may even show ossifications [9]. Similar to encapsulated tumors, the long term outcome was related to the
With complete resection, 29.5% of patients experienced a recurrence within 5 years of surgery whereas all partially removed tumors had recurred by that time (log rank test: p ⫽ 0.0254 after 10 months). No significant difference was observed whether the tumor matrix had been cauterized or resected (26.1% and 31.3% after 5 years, respectively). P describes the probability to remain clinically stable.
6
For meningiomas with a well defined capsule, only 20.4% of patients showed a clinical recurrence during follow-up compared to a recurrence rate of 81.1% for en plaque meningiomas (log rank test: p ⫽ 0.0037 after 1 year). P describes the probability to remain clinically stable.
5
560 Surg Neurol 1999;52:552–62
Klekamp, Samii
extent of resection. Every attempt at complete resection must be made. The tumor matrix should be excised widely whenever possible. However, with infiltration of the pia mater or pronounced arachnoid scarring we consider complete resection without taking unacceptable risks impossible. RECURRENT MENINGIOMAS The worst long term results were associated with recurrent meningiomas. Only 45% could be removed completely. Postoperative neurological scores tended to be lower and 62.1% of them showed progressive neurological symptoms within the first postoperative year. Surgery for a recurrent meningioma has to deal with two pathophysiological mechanisms, each capable of causing progressive neurological deterioration: arachnoid scarring causing spinal cord tethering and the meningioma compressing the spinal cord. Postsurgical arachnoid scarring was found in 90% of these cases [34]. Arachnoid scarring may cause progressive neurological symptoms due to cord tethering, interference with spinal cord blood flow and obstruction of cerebrospinal fluid flow [15,21, 24,35]. Presumably due to this arachnoid scarring, patients with recurrent meningiomas tend to present with severe sensory disturbances, dysesthesias and pain more often than those with primary meningiomas [30]. Similar observations were made with dysraphic malformations and intramedullary tumors [20,31]. Surgery for arachnoid scarring is a very problematic undertaking [21]. Each attempt to resect arachnoid scarring will cause new arachnoid scarring. In order not to aggravate prob-
If arachnoid scarring was present, 67.8% of patients demonstrated a clinical recurrence compared to 31.5% without such arachnoid pathology (log rank test: p ⫽ 0.0013 after 4 months). P describes the probability to remain clinically stable.
7
After a first operation on a spinal meningioma, 30% showed a clinical recurrence within 5 years after surgery. After surgery for a recurrent meningioma, 87.4% recurred within that time (log rank test: p ⫽ 0.0166 after 1 month). P describes the probability to remain clinically stable.
8
lems of cord tethering in the long term, one has to try to limit arachnoid dissection as much as possible to just those steps which are required to untether the cord and allow safe removal of the meningioma. Arachnoid scars should be dissected sharply and with meticulous hemostasis. In such cases we recommend decompressing the subarachnoid space with a dural graft which will provide some protection at least against significant postoperative tethering and cerebrospinal fluid flow obstruction [21,29]. However, arachnoid scarring may also interfere with tumor removal. The arachnoidal sheath covering meningiomas operated for the first time is no longer present in recurrent meningiomas. If intact, this arachnoid not only protects the cord during surgery, it is also a barrier against infiltration of the pia or nerve roots. Thus, the relationship between tumor and surrounding tissues is often altered so that recurrent meningioma often infiltrates neighboring structures [13,30,34,35]. Furthermore, arachnoid scarring may obscure the interface between meningioma, arachnoid and pia mater completely. A multiple regression analysis revealed that a second operation on a meningioma per se was not associated with higher recurrence rates. But infiltrative growth and arachnoid scarring, which could be found in almost every patient with a recurrent meningioma, were independent factors associated with postoperative neurological deterioration. Therefore, the first surgeon to operate on a spinal meningioma is in a position of great responsibility.
Spinal Meningiomas
He has the best opportunity to provide a cure for the patient. Once the first attempt has failed and the tumor recurs, it will be very difficult to achieve a satisfactory long-term result.
Surg Neurol 561 1999;52:552–62
13.
14.
Conclusions 15.
1. Complete resection of a spinal meningioma should be attempted in every case. With complete resection, long-term prognosis is excellent. 2. Surgery should be followed by rehabilitation programs even for patients in advanced age. Recovery of neurological deficits can almost always be expected. 3. En plaque and infiltrative meningiomas should be seen as a separate entity. They remain surgical challenges due to their extensive tumor matrix and infiltrative nature. 4. Arachnoid scarring and cord tethering may pose additional problems, particularly in surgery for recurrent meningiomas, and has to be dealt with intraoperatively as well. A dural graft seems to offer reasonable protection against retethering.
16. 17.
18. 19. 20. 21.
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COMMENTARY
This retrospective study carefully documents the clinical features and outcomes in a large surgical series of patients with spinal meningiomas managed at a single institution over a long time period. While the absolute numbers and percentages reported in this study probably reflect a substantial referral and treatment bias, there are a number of noteworthy observations. First, most patients do well after gross total resection of well-circumscribed spinal meningiomas, even those with significant neurologic deficits at presentation. Secondly, the recurrence rate in this subset of tumors seems to be independent of management of the dural attachment (i.e., resect and patch vs. coagulate). Thirdly,
as in most other instances of benign extramedullary tumors, gross total resection at the first operation offers the best opportunity for long-term tumor control or cure. Finally, infiltrative or en plaque meningiomas present a considerable surgical challenge. The recurrence rate and potential for significant neurologic morbidity either during primary removal or surgery for recurrence are significant. Paul C. McCormick, M.D. Neurological Surgery Columbia–Presbyterian Medical Center New York, New York, USA There are some interesting findings in this review. I was surprised to learn that 14.7% of the patients with spinal meningioma had a recurrence, and that the overall recurrence rate was calculated to be 21% at one year and 40.3% at 5 years. Without reviewing our data, I would have guessed that the rate would be much lower. Clearly, a surgeon must be cautious about the prognosis in cases of spinal meningioma, especially if the tumor is en plaque or has recurred. Russel H. Patterson, Jr., M.D. Neurosurgeon New York, New York, USA
he world of 2025 can be broken down into three broad population groups: World 1, including the affluent advanced nations of Europe, the United States, and Japan; World 2, the middle, making up the bulk of the world’s population, whose immediate needs and resources will be in relative balance; and World 3, the destitute nations, those on the brink of starvation, living with the constant threat of disaster.
T
—Joseph Coates, John Mahaffie, and Andy Hines “2025: Scenarios of US and Global Society Reshaped by Science and Technology” (1997)