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Study Design: This was a prospective, double-blinded study of the magnetic resonance imaging findings in the neural axis of 140 neurologically normal typical adolescents with idiopathic scoliosis who were scheduled for scoliosis surgery., Objective: To detect the prevalence of spinal cord and neural axis abnormalities in this select population., Summary of Background Data: No similar study exists, although a few related studies were published., Methods: Full-length neural axis magnetic resonance imaging studies were reviewed independently by two radiologists who specialize in the spine., Results: Only four patients had a definite abnormality-one a small thoracic syrinx and the other three with a Chiari malformation. None of these required neurosurgery. All 140 patients had their scoliosis surgery without necrologic compromise., Conclusion: Routine magnetic resonance imaging evaluation of neurologically normal, typical adolescents with idiopathic scoliosis is not warranted, based on this study.

We reviewed magnetic resonance imaging studies of the thoracic spines of ninety asymptomatic individuals to determine the prevalence of abnormal anatomical findings. This group included sixty individuals who had no history of any thoracic or lumbar pain and thirty individuals who had a history of low-back pain only. In addition, we reviewed imaging studies of eighteen patients who had an operatively proved herniation of a thoracic disc and studies of thirty-one patients who had been seen with thoracic pain. Sagittal T1-weighted spin-echo and axial multiplanar gradient refocused images at each disc level were interpreted by us (two neuroradiologists and two orthopaedic spine surgeons); we had no clinical information about the patients. Sixty-six (73 percent) of the ninety asymptomatic individuals had positive anatomical findings at one level or more. These findings included herniation of a disc in thirty-three subjects (37 percent), bulging of a disc in forty-eight (53 percent), an annular tear in fifty-two (58 percent), deformation of the spinal cord in twenty-six (29 percent), and Scheuermann end-plate irregularities or kyphosis in thirty-four (38 percent). This study documents the high prevalence of anatomical irregularities, including herniation of a disc and deformation of the spinal cord, on the magnetic resonance images of the thoracic spine in asymptomatic individuals. We emphasize that these findings represent roentgenographic abnormalities only, and any clinical decisions concerning the treatment of pain in the thoracic spine usually require additional studies.

CT myelography and MRI provide the best means of preoperatively assessing patients with spinal deformities. Owing to its noninvasive nature and its superior soft-tissue contrast, MRI represents the single best modality in the evaluation of a patient with any deformity. MRI allows complete preoperative surgical planning and obviates the need for any additional studies. Screening of the entire cord in a patient with a deformity is best accomplished with sagittal and coronal (as needed) T1W images. These images allow assessment of the cord for compression, tethering, syrinx, enlargement, and Arnold-Chiari malformation. Evaluation of cord compression at the apex of a curve is the single most important consideration other than the diagnosis of intrinsic cord abnormality. Subsequent sagittal or axial T2W images may be helpful if specific abnormalities are noted on T1W screening images. Coronal images are particularly helpful in patients with prominent curves or in those with vertebral anomalies. Additionally, coronal images may be useful in assessing patients with suspected diastematomyelia. Advances in hardware and software design have resulted in marked improvements in the ability to satisfactorily image all aspects of patients with spinal deformities. New phased array coils allow rapid imaging of larger portions of the spine. For instance, a complete MRI of the spine can be performed in a child in the same length of time that would have been necessary for a single lumbar examination when MRI was in it's infancy. The use of fast spin-echo imaging also permits more rapid acquisition times. CT myelography remains useful for those patients who cannot undergo MRI or for those with specific abnormalities such as multilevel central spinal stenosis when dynamic information obtained during the myelogram might be helpful. CT myelography represents the only means of assessing the central spinal canal of patients with metallic instrumentation in place. With the exception of these limited applications, MRI has replaced CT myelography as the imaging study of choice in the evaluation and examination of patients with spinal deformities.

The authors report 18 cases of surgically proved spontaneous epidural hematoma of the lumbar spine. The clinical findings in spontaneous epidural hematoma were identical to those in acute disk herniation. Underlying disk abnormalities were common; the majority of hematomas (14 of 18, 78%) were associated with small concomitant disk herniations or underlying annular tears. The magnetic resonance imaging and computed tomographic findings were similar to those in extruded/free-fragment disk herniation. The strong coincidence between epidural hematoma and underlying disk disruption (annular tear or herniation) leads the authors to postulate that spontaneous epidural hematoma results from tearing of fragile epidural veins lying adjacent to the displaced anulus or nucleus.

An interinstitutional study on the failed back surgery syndrome (FBSS) has determined that failure to recognize or adequately treat lateral stenosis of the lumbar spine with resultant nerve irritation and/or compression comprised the primary etiology in 57% to 58% of patients. Other common causes were recurrent or persistent disk herniation and lumbosacral adhesive arachnoiditis. The diagnosis of stenosis was made either by high-resolution CT scan of the lumbar spine or by directly testing lateral canal and for animal patency at the time of surgery. It is now appreciated that the process of degenerative disk disease, particularly when enhanced by diskectomy, results in progressive loss of intervertebral disk volume and predisposes to future ipsilateral or contralateral lateral spinal stenosis. Degenerative disk disease is ultimately a bilateral process and therefore surgical exposure should be bilateral. The direct and indirect costs of FBSS to patients and to society as well as the toll in human suffering are very high. This is particularly a matter of concern when it is realized that for many FBSS patients, surgery could have been avoided in the first place by preventive care or by innovative conservative treatment. When surgery is indicated, adequate diagnostic tests and the execution of appropriate procedures based upon this information should largely prevent the failed back surgery syndrome.

The reliability and accuracy of two-compartment temporomandibular joint (TMJ) arthrography was compared with MR imaging on the basis of an analysis of surgical findings obtained from joints that had been studied preoperatively with arthrography or MR or, in some cases, both procedures. Seven hundred forty-three consecutive TMJ arthrograms were successfully obtained in a total of 443 patients by using a single 27-gauge needle and a two-compartment technique in each joint. There was a 100% correlation with surgical findings in 218 radiologically abnormal joints operated on within 90 days of arthrography with respect to the presence or degree of meniscus displacement and normal or abnormal disk morphology and function. In 604 patients 1052 TMJs were studied with high-field-strength surface-coil MR. Surgical findings were available for correlation in 170 of the joints studied. Forty-three joints were studied with both two-compartment arthrography and MR. Eight operated joints had been imaged successfully with both two-compartment arthrography and MR. Both methods of evaluation provided highly reliable and accurate information regarding meniscus position and shape. Arthrography was superior to MR in detecting capsular adhesions and the presence or absence of perforation of the disk or meniscus attachments. Simple meniscectomy (with or without insertion of a temporary Silastic TMJ implant) was the most frequently performed surgical procedure in the series, followed by meniscus repositioning procedures. Joint effusions, failed TMJ implants, and avascular necrosis were demonstrated best with MR. Soft-tissue lesions, including intrinsic degeneration of the meniscus, anomalous muscle development, muscle atrophy, tendinitis, and injuries such as contusions and hematomas, were demonstrated only with MR. Partial-flip-angle GRASS (gradient-recalled acquisition in the steady state) techniques permit both fast scanning and study of functional joint dynamic. Joint fluid may appear as high signal intensity on GRASS images because of T2*-weighting. We recommend MR as the procedure of choice for diagnosis of uncomplicated internal derangements of the TMJ. Two-compartment arthrography with videofluoroscopy is an important ancillary procedure that should be performed whenever capsular adhesions or perforations are suspected and not demonstrated with MR and whenever MR is inconclusive.

Nineteen abnormal temporomandibular joints (TMJs) imaged with high-field-strength surface-coil MR are presented to illustrate specific changes associated with disk derangement, trauma, and previous surgery. Cases were selected from a series of 248 TMJ MR studies in 144 patients (9-68 year old, 130 females and 14 males) performed during a 5-month period. Surgical findings were available for correlation in 44 of the 248 joints studied. Increased signal caused by myxoid degeneration within the degenerating meniscus was seen, as were pathologic changes including atrophy, fibrosis, and contracture of masticatory muscles occurring with internal derangements. Advantages and limitations of MR are discussed with reference to arthrography and videofluoroscopy. High-resolution and partial-flip-angle images of a normal joint are provided for comparison. In most clinical circumstances, MR is the procedure of choice when examining the TMJ, because it provides contrast resolution of soft-tissue structures superior to that of conventional imaging techniques.

With the advent of computed tomography of the lumbar spine, the theories of a small number of pioneering physicians regarding the pathologic sequela of degenerative disc disease and the entities of central and lateral spinal stenosis have been translated into objective determinations which can now be observed by all. CT scanning has provided clinicians with a better appreciation of the diagnostic limitations of myelography and of the pathologic sequela of hemilaminectomy, dorsal-lateral fusion, and discectomy itself. Since the identification by CT scanning of the loss of disc volume, leading to lateral nerve entrapment and nerve compression resulting from fusion overgrowth, it has become clear that our present modes of therapy require comprehensive reevaluation. Because of the findings of CT scanning, dorsal-lateral fusion now appears to have a much reduced role in the treatment of degenerative disc disease and spinal stenosis. In an era in which unnecessary surgery is a matter of concern, CT scanning is an important means of ensuring that surgery will be undertaken only after thorough pathologic conditions.

Two cases of congenital bronchopulmonary foregut malformation are reported and another 27 cases reviewed and the findings analyzed. The left lower lobe and the entire right lung are the most common locations of pulmonary involvement. The distal portion of the esophagus or cardioesophageal junction was the most common site of communication (83%). The majority of the patients (60%) presented in the first eight months of life, and the incidence in females was nearly twice that in males. Chronic cough, recurrent pneumonias and respiratory distress were the most common clinical findings, whereas two patients were totally asymptomatic. The esophagogram was the single most useful diagnostic procedure (82%). The microscopic structure of the congenital fistula resembled esophagus, bronchus or both. Surgical treatment was curative in most instances. Sime deaths occurred prior to corrective surgery, whereas the postoperative deaths in most instances were related to severe associated congenital anomalies. We believe a common embryologic pathogenesis leads to the formation of a variety of bronchopulmonary foregut malformations. These bronchopulmonary foregut malformations include intralobar and extralobar sequestrations, pulmonary sequestration with patent, or involuted--partial or complete--gastroesophageal communication, esophageal or gastric diverticula, and esophageal or bronchogenic duplication cysts.

Fifty-four maxillofacial three-dimensional computed tomographic examinations were performed during a 12-month period for the purpose of surgical planning. Pathologic entities in the series included trauma, neoplasia, cleft palate, and other developmental anomalies. Computer-assisted mandibular disarticulation was performed routinely after each study to permit direct viewing of the mandible or maxilla in isolation. Three-dimensional computed tomography is a useful technique for maxillofacial surgical planning.

High-resolution computed tomography (CT) has dramatically expanded the understanding of lumbar spine anatomy. The procedure provides accurate preoperative assessment of bony and soft tissue pathology; directly visualizes the pathologic processes affecting the spine; and furnishes direct evidence of nerve root involvement by bony stenosis, herniated disc, and postoperative perineural fibrosis. The bony spinal and intervertebral nerve root canals and soft tissues can be imaged, herniated and sequestered discs identified, and causes of postoperative pain syndrome differentiated. High-resolution CT defines nerve root entrapment more accurately than any other imaging method currently used in the study of lumbar spine disease. Because it can provide complete preoperative information regarding bone and soft tissue pathology, the procedure can reasonably be expected to significantly reduce the incidence of "failed back surgery syndrome."

Inadequate low back care has now been clearly identified as perhaps the greatest single waste of health care resources in the United States. Low back care failure represents a particularly frustrating and challenging entity. Statistics suggest that 25,000 to 50,000 FBSS cases occur each year. This is a public health problem that should be of the highest level of concern. Modern understanding and technical prowess allow us to study past therapeutic failures and thus gain the knowledge necessary to do better in the future. We sincerely hope that our colleagues will give careful consideration to the material presented here.