•
•
Neuroradiology
Myelography in the Evaluation of Paravertebral Mass Lesions in Infants and Children 1 Donald R. Kirks, M.D.,2 Paul E. Berger, M.D.,3 Charles R. Fltz, M.D., and Derek C. Harwood-Nash, M.B., Ch.B., F.R.C.P.(C)
The clinical, pathological, and radiological features in 21 pediatric patients with intraspinal extension of paravertebral mass lesions are presented. Intraspinal extension may be present in the absence of either neurological symptoms or bony abnormalities. It is essential that myelography be performed prior to thoracotomy or laparotomy in such cases. INDEX TERMS: Myelography, indications. Spine, neoplasms Radiology 119:603-608, June 1976
ARAVERTEBRAL mass 'lesions are a common diagnostic problem in pediatric radiology. Twenty-four patients with such lesions seen at the Hospital for Sick Children from 1965 through 1974 were studied and their clinical charts, spinal radiographs, myelograms, and pathological diagnoses were reviewed. A total of 21 patients had surgical confirmation of intraspinal extension of tumor at laminectomy and were subjected to further evaluation (Fig. 1; TABLE I).
P
6 8 10 AGE (YEARS)
12
14
16+
MATERIAL AND FINDINGS
Clinical: There were 9 boys and 12 girls ranging from 2 days to 14 years of age (mean, 3 yr. 10 mo.). Five patients had ganglioneuroma; their mean age was 8 years, and none had neurological symptoms. Twelve patients had neuroblastoma; their mean age was 2 yr. 7 mo., and 2 of them had no neurological symptoms. Pathology: Of the 21 tumors with intraspinal extension, 17 (12 neuroblastomas and 5 ganglioneuromas) were neurogenic in origin. The remaining tumors consisted of 1 teratoma, 1 embryonal sarcoma, 1 Ewing's sarcoma, and 1 leukemic chloroma. . Spinal Radiographs: Paravertebral mass lesions were present in all 21 patients. Thirteen were thoracic. Four neuroblastomas and one ganglioneuroma contained calcification. The most common bone change was pediculate erosion (TABLE I). Rib splaying or erosion occurred in 33 %. Five patients had no bony abnormalities. Myelograms: The myelograms were positive in 19 cases; there was one false-negative, and one was considered equivocal. All but one of the 21 surgically confirmed intraspinal extensions were extradural, the leu-
Fig. 1. Summary of data in 21 patients with intraspinal extension of a paravertebral mass lesion. A. Levels of paravertebral masses. B. Levels of myelographic abnormalities. C. Agedistribution. D. Anatomical sitesof intraspinal extension. kemic chloroma being the only exception. Complete blockage was more common than displacement of the contrast column by an extradural mass. In 4 patients the myelographic abnormality was distant from the level of the paravertebral mass (TABLE I).
1 From the Department of Radiology, Division of Neuroradiology, Hospital for Sick Children, Toronto, Ontario, Canada. Accepted for publication in November 1975. 2 Current address: Department of Radiology, Children's Medical Center, University of Texas Health Science Center at Dallas, Dallas, Texas
75235. 3
Current address: Department of Radiology, Buffalo Children's Hospital, Buffalo, N. Y.
603
sjh
DONALD R. KIRKS AND OTHERS
604
June 1976
Fig. 2. Extradural extension of tumor in a 22-month-old child with pelvic and sacrococcygeal embryonal sarcoma. A and B. Anteroposterior aortogram (A) and lateral aortogram (B) demonstrate a vascular mass in the posterior pelvis, supplied by branches of the right internal iliac artery. Intrasacral neovascularity (arrows) is clearly visible. C. Smooth compression of the dural sac (arrows) is noted at myelography.
Table I: Summary of Radiological Findings in 21 Patients with Intraspinal Extension of a Paravertebral Mass Radiological Finding Paravertebral mass Calcification Bone abnormal ities Spine Pedicle abnormal ity Eroded pedicle Increased interpediculate distance Enlarged intervertebral foramina Normal Abnormal intervertebral disk space Vertebral body abnormality Rib abnormal ity Normal Myelographic abnormalities Type of lesion Extradural Block Mass Intradural Lesion away from paravertebral mass
No. of Patients 21
5 16 12 12
9 4 4 9 3 3 7 5 21 20 12
8 1 4
DISCUSSION
We have adopted a policy of routine myelographic evaluation of paravertebral mass lesions in infants and children. The majority of such lesions are neurogenic. The clinical presentation is highly variable, and findings may include paraplegia, weakness, local pain, torticollis, loss of sphincter function, constipation, and urinary incontinence or frequency. However, the diagnosis of early neurological deficits may be extremely difficult, particularly in infants younger than 18 months of age (10); moreover, such patients may have no neurological abnormalities despite myelographic and surgical confirmation of extension.
Intraspinal extension of paravertebral mass lesions in infants and children has been described previously (1, 3, 9, 10, 13); however, the preoperative diagnosis, which is essential in planning treatment (10), has been insufficiently emphasized. In such cases, the initial therapy should consist of decompressive laminectomy with removal of as much extradural tumor as is surgically feasible (11, 12); this may not only stop progression of neurological deficits (1) but also prevent intraspinal bleeding, which may occur following removal of the mass at thoracotomy or laparotomy (5). The initial radiological evaluation should include anteroposterior and lateral plain films of either chest or abdomen, as well as a complete spinal series including oblique views. Although the differential diagnosis of paravertebral masses in infants and children is extensive (2, 4, 11, 14) (TABLE II), many lesions may be excluded on the basis of the clinical history and radiological features (3). Subsequent investigation may include tomography, a skeletal survey, excretory urography, and radionuclide bone imaging prior to complete myelography. Aortography and selective angiography are often helpful not only as an aid to diagnosis but also in delineating the vascular supply of the mass (Figs. 2 and 3). Paravertebral masses may contain calcification, confirming the great propensity of thoracic masses to extend intraspinally (10). Plain-film findings such as pedicle abnormalities (TABLE I) and rib erosion may suggest intraspinal extension. However, one-fourth of patients have no bone changes despite such extension, while, conversely, bone abnormalities may be present without intraspinal extension. This emphasizes the need for myelography prior to surgical intervention.
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Table II:
MYELOGRAPHY IN EVALUATION OF PARAVERTEBRAL MASS LESIONS
605
Neuroradiology
Differential Diagnosis of Paravertebral Masses in I nfants and Children (2,4,11,14)
Congenital Bronchopulmonary-foregut malformation Bronchogenic cyst Sequestration Enteric duplication Neurenteric cyst Lateral meningocele Cystic hygroma Thoracic duct cyst Germinoma Hamartoma Teratoma Infection Bacterial osteomyel itis Diskitis Tuberculosis Abscess Tumor Primary Neurogenic Neuroblastoma Ganglioneuroma Ganglioneuroblastoma Neurofibroma Neurilemmoma Osseocartil aginous Aneurysmal bone cyst Giant-cell tumor Chordoma Osteogenic sarcoma Osteoma Osteoblastoma Mesenchymal tumors and malignant counterpart Chondroma Fibroma Hemangioma Leiomyoma Lipoma Lymphangioma Myoma Xanthofibroma Pheochromocytoma Secondary Leukemia, lymphoma Neuroblastoma Wilms' tumor Trauma Hematoma Miscellaneous Extramedullary hematopoiesis Histiocytosis X
Although myelography is the least commonly performed special procedure in pediatric neuroradiology (8), its frequency is increasing due to improved techniques and awareness of the indications for such a study. The number of cases studied myelographically at our institution has increased from 62 in 1968 to 127 in 1974. Ten of the 21 patients in this series were studied during the last 2 years. The indications for and techniques of myelography in children, as well as the characteristics of pathological entities within the spinal canal, differ from those in the adult (7). Indications for myelography in the pediatric patient include limb weakness, a sensory deficit level, pain localized to a single vertebra, painful scoliosis, recurrent genitourinary probterns or constipation, pes cavus, spinal dysraphism with new or increasing neurological symptoms, a possible spinal arteriovenous malformation, paravertebral mass lesions, suspicion of tethered-cord syndrome, and possible traumatic injury to the spinal cord (6, 7, 9). Myelography in infants and children is both safe and
Fig. 3. A. Six-month-old infant with a huge, vascular retroperitoneal neuroblastoma displacing the aorta to the left and anteriorly. B. The dural sac is markedly attenuated from L1 to S1 (arrows). Huge epidural veins without a definite tumor mass were noted at laminectomy.
simple (7). It is usually performed under general anesthesia to permit adequate examination of the entire spinal subarachnoid space. Following puncture at the L4-L5 interspace with a 19 or 20 gauge needle, 3-15 ml of Pantopaque is instilled (9). Anteroposterior prone films of the entire subarachnoid space are obtained, as well as oblique views at the craniovertebral junction. The patient is then turned supine and postero-anterior spot films are obtained. In addition, prone cross-table lateral, supine cross-table lateral, and lateral decubitus views with a horizontal beam (Fig. 4) are obtained at the site of suspected pathology. Myelographic abnormalities involving intraspinal extension of paravertebral lesions are almost always extradural, most frequently producing a complete block with a classic "feathery" appearance (Fig. 5). Less frequently, the extradural tumor smoothly displaces the subarachnoid space (Figs. 2, 6, and 7), completely surrounds the contrast column (Fig. 3, B), or produces a localized defect in the margin of the subarachnoid space (Fig. 8). Myelography is especially helpful in those cases in which the level of the paravertebral mass differs from that of the intraspinal extension (Fig. 5). A lateral decubitus view at the level of the paravertebral mass, with the side containing the mass dependent, is essential to the diagnosis and is particularly valuable in detecting subtle extradural impressions (Figs. 4, Band 7, B). Bilateral decubitus views are valuable when the contrast-filled subarachnoid space is minimally asymmetric. A lateral decubitus view was not obtained in the only false-negative myelogram in this series (Fig. 9). Any abnormal extradural impression at myelography in a patient with a paravertebral tumor should be inter-
606
DONALD
R.
KIRKS AND OTHERS
June 1976
Fig. 4. Normal myelogram in a 6-year-old child with a left-sided ganglioneuroma extending from T7 to n2. A. Prone myelogram shows a flow defect at T9-no (arrows), suggesting an extradural mass. B. Left lateral decubitus film with the paravertebral mass dependent (arrows) is otherwise normal and excludes intraspinal extension.
Fig. 5. A. Extradural block in a 2-year-old child with right apical neuroblastoma. B. Myelogram shows a distant complete extradural block at T9-no. Laminectomy confirmed extradural tumor extending from T6 to T11.
preted as intraspinal extension, and decompressive laminectomy should be performed prior to definitive removal of the extraspinal mass (10). One positive myelogram in our series showed complete encasement of the dural sac (Fig. 3). At laminectomy, huge epidural veins without a definite tumor mass were identified, although biopsy was not obtained, indicating intraspinal extension and calling for the appropriate therapeutic response.
SUMMARY
Paravertebral tumors may extend intraspinally, either with or without associated neurological symptoms and bony radiographic abnormalities. Since the presence of such extension alters the choice of initial surgical therapy, myelography is indicated as part of the preoperative evaluation of paravertebral mass lesions in infants and children.
Vol. 119
MYELOGRAPHY IN EVALUATION OF PARAVERTEBRAL MASS LESIONS
607
Neuroradiology
Fig. 6. Intraspinal extension of ganglioneuroma in an asymptomatic 20-month-old child. A. There is a superior, posterior mediastinal calcified mass on the left side (arrow) with splaying and erosion of the second rib. B. Myelogram demonstrates intraspinal extension from T1 to T4.
REFERENCES 1. Balakrishnan V, Rice MS, Simpson DA: Spinal neuroblastomas. Diagnosis, treatment, and prognosis. J Neurosurg 40:631638, May 1974 2. Benton C, Silverman FN: Some mediastinal lesions in children. Semin RoentgenoI4:91-101, Jan 1969 3. Fagan CJ, Swischuk LE: Dumbbell neuroblastoma or ganglioneuroma of the spinal canal. Am J Roentgenol 120:453-460, Feb 1974 4. Felson B: The mediastinum. Semin Roentgenol 4:41-58, Jan 1969 5. Fortner J, Nicastri A, Murphy ML: Neuroblastoma: natural history and results of treating 133 cases. Am Surg 167:132-142, Jan 1968 6. Franken EA Jr: Spinal cord injury in the newborn infant. Pediatr RadioI3:101-104, Mar 1975 7. Harwood-Nash DC: Myelography in children. Semin RoentgenoI7:297-312, Jul 1972 8. Harwood-Nash DC: Paediatric neuroradiology. Radiol Clin North Am 10:313-331, Aug 1972 9. Harwood-Nash DC, Fitz CR: Neuroradiological techniques and indications in infancy and childhood. [In] Kaufmann HJ, ed: Skull, Spine and Contents. Vol 5 of Progress in Pediatric Radiology. Basel, Karger, 1976, pp 2-'-85 10. Lepintre J, Schweisguth 0, Labrune M, et al: Les neuroblastomes en sablier. Etude de vingt-deux cas. Arch Franc Pediatr 26:829-847, Oct 1969 11. Matson DD: Neurosurgery of Infancy and Childhood. Springfield, III., Thomas, 2d Ed, 1969, pp 676-681 12 Mustard WT, Ravitch MM, Snyder WH Jr, et ai, ed: Pediatric Surgery. Chicago, Year Book, 2d Ed, 1969, P 422 13. Shephard RH, Sutton D: Dumbbell ganglioneuromata of the spine with a report of four cases. Br J Surg 45:305-317, Jan 1958 14. Werner JL, Taybi H: Presacral masses in childhood. Am J Roentgenol 109:403-410, Jun 1970 Derek C. Harwood-Nash, M.D. Department of Radiology Division of Neuroradiology Hospital for Sick Children Toronto, Ontario M5G 1X8, Canada
Fig. 7. A. Six-month-old child with massive extradural extension of lumbar neuroblastoma between L1 and L5. B. Fourteen-year-old child with a ganglioneuroma on the left, extending from T9 to L1. There is widening of the T10-T11 interspace and increased separation of the pedicles of T10 and T11 (open arrows). The left lateral decubitus myelogram shows minimal flattening of the contrast column (closed arrow), indicating extradural extension. (Figures 8 and 9 are on page 608)
Fig. 8. A. Localized extradural extension in a 14-year-old child with a huge right thoracic ganglioneuroma. B. Myelogram demonstrates a localized defect in the subarachnoid space (arrows), caused by extension of tumor.
Fig. 9. A. False-negative myelogram in a 3-year-old child with a ganglioneuroma extending from T9 to n2 (arrows). B. The prone myelogram is normal. A lateral decubitus film was inadvertently omitted. Thoracotomy revealed a posterior mediastinal mass 6 cm in diameter with intraspinal extension at no.
608
•
Neuroradiology
Myelography in the Evaluation of Paravertebral Mass Lesions in Infants and Children 1 Donald R. Kirks, M.D.,2 Paul E. Berger, M.D.,3 Charles R. Fltz, M.D., and Derek C. Harwood-Nash, M.B., Ch.B., F.R.C.P.(C)
The clinical, pathological, and radiological features in 21 pediatric patients with intraspinal extension of paravertebral mass lesions are presented. Intraspinal extension may be present in the absence of either neurological symptoms or bony abnormalities. It is essential that myelography be performed prior to thoracotomy or laparotomy in such cases. INDEX TERMS: Myelography, indications. Spine, neoplasms Radiology 119:603-608, June 1976
ARAVERTEBRAL mass 'lesions are a common diagnostic problem in pediatric radiology. Twenty-four patients with such lesions seen at the Hospital for Sick Children from 1965 through 1974 were studied and their clinical charts, spinal radiographs, myelograms, and pathological diagnoses were reviewed. A total of 21 patients had surgical confirmation of intraspinal extension of tumor at laminectomy and were subjected to further evaluation (Fig. 1; TABLE I).
P
6 8 10 AGE (YEARS)
12
14
16+
MATERIAL AND FINDINGS
Clinical: There were 9 boys and 12 girls ranging from 2 days to 14 years of age (mean, 3 yr. 10 mo.). Five patients had ganglioneuroma; their mean age was 8 years, and none had neurological symptoms. Twelve patients had neuroblastoma; their mean age was 2 yr. 7 mo., and 2 of them had no neurological symptoms. Pathology: Of the 21 tumors with intraspinal extension, 17 (12 neuroblastomas and 5 ganglioneuromas) were neurogenic in origin. The remaining tumors consisted of 1 teratoma, 1 embryonal sarcoma, 1 Ewing's sarcoma, and 1 leukemic chloroma. . Spinal Radiographs: Paravertebral mass lesions were present in all 21 patients. Thirteen were thoracic. Four neuroblastomas and one ganglioneuroma contained calcification. The most common bone change was pediculate erosion (TABLE I). Rib splaying or erosion occurred in 33 %. Five patients had no bony abnormalities. Myelograms: The myelograms were positive in 19 cases; there was one false-negative, and one was considered equivocal. All but one of the 21 surgically confirmed intraspinal extensions were extradural, the leu-
Fig. 1. Summary of data in 21 patients with intraspinal extension of a paravertebral mass lesion. A. Levels of paravertebral masses. B. Levels of myelographic abnormalities. C. Agedistribution. D. Anatomical sitesof intraspinal extension. kemic chloroma being the only exception. Complete blockage was more common than displacement of the contrast column by an extradural mass. In 4 patients the myelographic abnormality was distant from the level of the paravertebral mass (TABLE I).
1 From the Department of Radiology, Division of Neuroradiology, Hospital for Sick Children, Toronto, Ontario, Canada. Accepted for publication in November 1975. 2 Current address: Department of Radiology, Children's Medical Center, University of Texas Health Science Center at Dallas, Dallas, Texas
75235. 3
Current address: Department of Radiology, Buffalo Children's Hospital, Buffalo, N. Y.
603
sjh
DONALD R. KIRKS AND OTHERS
604
June 1976
Fig. 2. Extradural extension of tumor in a 22-month-old child with pelvic and sacrococcygeal embryonal sarcoma. A and B. Anteroposterior aortogram (A) and lateral aortogram (B) demonstrate a vascular mass in the posterior pelvis, supplied by branches of the right internal iliac artery. Intrasacral neovascularity (arrows) is clearly visible. C. Smooth compression of the dural sac (arrows) is noted at myelography.
Table I: Summary of Radiological Findings in 21 Patients with Intraspinal Extension of a Paravertebral Mass Radiological Finding Paravertebral mass Calcification Bone abnormal ities Spine Pedicle abnormal ity Eroded pedicle Increased interpediculate distance Enlarged intervertebral foramina Normal Abnormal intervertebral disk space Vertebral body abnormality Rib abnormal ity Normal Myelographic abnormalities Type of lesion Extradural Block Mass Intradural Lesion away from paravertebral mass
No. of Patients 21
5 16 12 12
9 4 4 9 3 3 7 5 21 20 12
8 1 4
DISCUSSION
We have adopted a policy of routine myelographic evaluation of paravertebral mass lesions in infants and children. The majority of such lesions are neurogenic. The clinical presentation is highly variable, and findings may include paraplegia, weakness, local pain, torticollis, loss of sphincter function, constipation, and urinary incontinence or frequency. However, the diagnosis of early neurological deficits may be extremely difficult, particularly in infants younger than 18 months of age (10); moreover, such patients may have no neurological abnormalities despite myelographic and surgical confirmation of extension.
Intraspinal extension of paravertebral mass lesions in infants and children has been described previously (1, 3, 9, 10, 13); however, the preoperative diagnosis, which is essential in planning treatment (10), has been insufficiently emphasized. In such cases, the initial therapy should consist of decompressive laminectomy with removal of as much extradural tumor as is surgically feasible (11, 12); this may not only stop progression of neurological deficits (1) but also prevent intraspinal bleeding, which may occur following removal of the mass at thoracotomy or laparotomy (5). The initial radiological evaluation should include anteroposterior and lateral plain films of either chest or abdomen, as well as a complete spinal series including oblique views. Although the differential diagnosis of paravertebral masses in infants and children is extensive (2, 4, 11, 14) (TABLE II), many lesions may be excluded on the basis of the clinical history and radiological features (3). Subsequent investigation may include tomography, a skeletal survey, excretory urography, and radionuclide bone imaging prior to complete myelography. Aortography and selective angiography are often helpful not only as an aid to diagnosis but also in delineating the vascular supply of the mass (Figs. 2 and 3). Paravertebral masses may contain calcification, confirming the great propensity of thoracic masses to extend intraspinally (10). Plain-film findings such as pedicle abnormalities (TABLE I) and rib erosion may suggest intraspinal extension. However, one-fourth of patients have no bone changes despite such extension, while, conversely, bone abnormalities may be present without intraspinal extension. This emphasizes the need for myelography prior to surgical intervention.
Vol. 119
Table II:
MYELOGRAPHY IN EVALUATION OF PARAVERTEBRAL MASS LESIONS
605
Neuroradiology
Differential Diagnosis of Paravertebral Masses in I nfants and Children (2,4,11,14)
Congenital Bronchopulmonary-foregut malformation Bronchogenic cyst Sequestration Enteric duplication Neurenteric cyst Lateral meningocele Cystic hygroma Thoracic duct cyst Germinoma Hamartoma Teratoma Infection Bacterial osteomyel itis Diskitis Tuberculosis Abscess Tumor Primary Neurogenic Neuroblastoma Ganglioneuroma Ganglioneuroblastoma Neurofibroma Neurilemmoma Osseocartil aginous Aneurysmal bone cyst Giant-cell tumor Chordoma Osteogenic sarcoma Osteoma Osteoblastoma Mesenchymal tumors and malignant counterpart Chondroma Fibroma Hemangioma Leiomyoma Lipoma Lymphangioma Myoma Xanthofibroma Pheochromocytoma Secondary Leukemia, lymphoma Neuroblastoma Wilms' tumor Trauma Hematoma Miscellaneous Extramedullary hematopoiesis Histiocytosis X
Although myelography is the least commonly performed special procedure in pediatric neuroradiology (8), its frequency is increasing due to improved techniques and awareness of the indications for such a study. The number of cases studied myelographically at our institution has increased from 62 in 1968 to 127 in 1974. Ten of the 21 patients in this series were studied during the last 2 years. The indications for and techniques of myelography in children, as well as the characteristics of pathological entities within the spinal canal, differ from those in the adult (7). Indications for myelography in the pediatric patient include limb weakness, a sensory deficit level, pain localized to a single vertebra, painful scoliosis, recurrent genitourinary probterns or constipation, pes cavus, spinal dysraphism with new or increasing neurological symptoms, a possible spinal arteriovenous malformation, paravertebral mass lesions, suspicion of tethered-cord syndrome, and possible traumatic injury to the spinal cord (6, 7, 9). Myelography in infants and children is both safe and
Fig. 3. A. Six-month-old infant with a huge, vascular retroperitoneal neuroblastoma displacing the aorta to the left and anteriorly. B. The dural sac is markedly attenuated from L1 to S1 (arrows). Huge epidural veins without a definite tumor mass were noted at laminectomy.
simple (7). It is usually performed under general anesthesia to permit adequate examination of the entire spinal subarachnoid space. Following puncture at the L4-L5 interspace with a 19 or 20 gauge needle, 3-15 ml of Pantopaque is instilled (9). Anteroposterior prone films of the entire subarachnoid space are obtained, as well as oblique views at the craniovertebral junction. The patient is then turned supine and postero-anterior spot films are obtained. In addition, prone cross-table lateral, supine cross-table lateral, and lateral decubitus views with a horizontal beam (Fig. 4) are obtained at the site of suspected pathology. Myelographic abnormalities involving intraspinal extension of paravertebral lesions are almost always extradural, most frequently producing a complete block with a classic "feathery" appearance (Fig. 5). Less frequently, the extradural tumor smoothly displaces the subarachnoid space (Figs. 2, 6, and 7), completely surrounds the contrast column (Fig. 3, B), or produces a localized defect in the margin of the subarachnoid space (Fig. 8). Myelography is especially helpful in those cases in which the level of the paravertebral mass differs from that of the intraspinal extension (Fig. 5). A lateral decubitus view at the level of the paravertebral mass, with the side containing the mass dependent, is essential to the diagnosis and is particularly valuable in detecting subtle extradural impressions (Figs. 4, Band 7, B). Bilateral decubitus views are valuable when the contrast-filled subarachnoid space is minimally asymmetric. A lateral decubitus view was not obtained in the only false-negative myelogram in this series (Fig. 9). Any abnormal extradural impression at myelography in a patient with a paravertebral tumor should be inter-
606
DONALD
R.
KIRKS AND OTHERS
June 1976
Fig. 4. Normal myelogram in a 6-year-old child with a left-sided ganglioneuroma extending from T7 to n2. A. Prone myelogram shows a flow defect at T9-no (arrows), suggesting an extradural mass. B. Left lateral decubitus film with the paravertebral mass dependent (arrows) is otherwise normal and excludes intraspinal extension.
Fig. 5. A. Extradural block in a 2-year-old child with right apical neuroblastoma. B. Myelogram shows a distant complete extradural block at T9-no. Laminectomy confirmed extradural tumor extending from T6 to T11.
preted as intraspinal extension, and decompressive laminectomy should be performed prior to definitive removal of the extraspinal mass (10). One positive myelogram in our series showed complete encasement of the dural sac (Fig. 3). At laminectomy, huge epidural veins without a definite tumor mass were identified, although biopsy was not obtained, indicating intraspinal extension and calling for the appropriate therapeutic response.
SUMMARY
Paravertebral tumors may extend intraspinally, either with or without associated neurological symptoms and bony radiographic abnormalities. Since the presence of such extension alters the choice of initial surgical therapy, myelography is indicated as part of the preoperative evaluation of paravertebral mass lesions in infants and children.
Vol. 119
MYELOGRAPHY IN EVALUATION OF PARAVERTEBRAL MASS LESIONS
607
Neuroradiology
Fig. 6. Intraspinal extension of ganglioneuroma in an asymptomatic 20-month-old child. A. There is a superior, posterior mediastinal calcified mass on the left side (arrow) with splaying and erosion of the second rib. B. Myelogram demonstrates intraspinal extension from T1 to T4.
REFERENCES 1. Balakrishnan V, Rice MS, Simpson DA: Spinal neuroblastomas. Diagnosis, treatment, and prognosis. J Neurosurg 40:631638, May 1974 2. Benton C, Silverman FN: Some mediastinal lesions in children. Semin RoentgenoI4:91-101, Jan 1969 3. Fagan CJ, Swischuk LE: Dumbbell neuroblastoma or ganglioneuroma of the spinal canal. Am J Roentgenol 120:453-460, Feb 1974 4. Felson B: The mediastinum. Semin Roentgenol 4:41-58, Jan 1969 5. Fortner J, Nicastri A, Murphy ML: Neuroblastoma: natural history and results of treating 133 cases. Am Surg 167:132-142, Jan 1968 6. Franken EA Jr: Spinal cord injury in the newborn infant. Pediatr RadioI3:101-104, Mar 1975 7. Harwood-Nash DC: Myelography in children. Semin RoentgenoI7:297-312, Jul 1972 8. Harwood-Nash DC: Paediatric neuroradiology. Radiol Clin North Am 10:313-331, Aug 1972 9. Harwood-Nash DC, Fitz CR: Neuroradiological techniques and indications in infancy and childhood. [In] Kaufmann HJ, ed: Skull, Spine and Contents. Vol 5 of Progress in Pediatric Radiology. Basel, Karger, 1976, pp 2-'-85 10. Lepintre J, Schweisguth 0, Labrune M, et al: Les neuroblastomes en sablier. Etude de vingt-deux cas. Arch Franc Pediatr 26:829-847, Oct 1969 11. Matson DD: Neurosurgery of Infancy and Childhood. Springfield, III., Thomas, 2d Ed, 1969, pp 676-681 12 Mustard WT, Ravitch MM, Snyder WH Jr, et ai, ed: Pediatric Surgery. Chicago, Year Book, 2d Ed, 1969, P 422 13. Shephard RH, Sutton D: Dumbbell ganglioneuromata of the spine with a report of four cases. Br J Surg 45:305-317, Jan 1958 14. Werner JL, Taybi H: Presacral masses in childhood. Am J Roentgenol 109:403-410, Jun 1970 Derek C. Harwood-Nash, M.D. Department of Radiology Division of Neuroradiology Hospital for Sick Children Toronto, Ontario M5G 1X8, Canada
Fig. 7. A. Six-month-old child with massive extradural extension of lumbar neuroblastoma between L1 and L5. B. Fourteen-year-old child with a ganglioneuroma on the left, extending from T9 to L1. There is widening of the T10-T11 interspace and increased separation of the pedicles of T10 and T11 (open arrows). The left lateral decubitus myelogram shows minimal flattening of the contrast column (closed arrow), indicating extradural extension. (Figures 8 and 9 are on page 608)
Fig. 8. A. Localized extradural extension in a 14-year-old child with a huge right thoracic ganglioneuroma. B. Myelogram demonstrates a localized defect in the subarachnoid space (arrows), caused by extension of tumor.
Fig. 9. A. False-negative myelogram in a 3-year-old child with a ganglioneuroma extending from T9 to n2 (arrows). B. The prone myelogram is normal. A lateral decubitus film was inadvertently omitted. Thoracotomy revealed a posterior mediastinal mass 6 cm in diameter with intraspinal extension at no.
608
