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Biomedical subjects

B M Onofrio

Publications and source records attributed to B M Onofrio.

At least 19 recordsLinked to original sources
PubMed1995

Intraneural perineurioma. A clonal neoplasm associated with abnormalities of chromosome 22.

The nature of perineurioma, variably termed "localized hypertrophic neuropathy," "intraneural neurofibroma," and "hypertrophic interstitial neuritis" has long been an issue of contention. Most authors consider it a neoplasm, but some a reactive process. Eight clinically and morphologically typical perineuriomas were studied by histologic, immunohistochemical and ultrastructural methods. One perineurioma was subject to tissue culture and cytogenetic study and another to fluorescence in situ hybridization (FISH) analysis. The patients, 3 males and 5 females, ranged in age from 11 to 38 years. All tumors were intraneural, and involved extremities (2 sciatic, 1 median, 1 femoral, 1 peroneal, 1 brachial plexus, 1 ulnar, and 1 radial). Neurologic symptoms, motor in all cases and sensory in 4, were present from 1 month to 7 years (mean 1.2 years). Fusiform, segmental nerve enlargement was clinically apparent in only two patients, but was evident on MRI in five of eight patients. Lesion length ranged from 3.5 to 30 cm, the largest involving the sciatic nerve from the obturator foramen to the knee. One lesion involved two nerve roots, but no association with a phakomatosis was noted. Treatment consisted of biopsy in six cases and resection in two cases. Histologically, pseudo-onion bulbs composed of epithelial membrane antigen-reactive, S-100 protein-negative perineurial cells surrounded myelinated or nonmyelinated nerve fibers. Many were accompanied by their S-100 protein-positive Schwann sheaths. Some whorls lacked a central axon. A single mitosis was noted in one case. The MIB-1 antigen labelling index ranged from 4% to 17%. Staining for p53 antigen in six cases showed no (2 of 6), rare (2 of 6), or scattered (2 of 6) immunoreactive nuclei. Cytogenetic analysis in one case demonstrated a chromosomally abnormal clone. Each of 16 metaphases was abnormal; the tumor cells appeared to be homozygously deficient for the region 22q11.2qter. In another case, 53% of interphase nuclei showed three FISH signals with a chromosome 14/22 probe, thus suggesting either monosomy for the centromere of chromosome 14 or that of chromosome 22.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMed1995

Spinal cord astrocytoma: pathological and treatment considerations.

Seventy-nine patients underwent surgery, with or without radiation therapy, for astrocytoma of the spinal cord. There were 43 tumors (54%) classified as pilocytic astrocytoma and 25 (32%) as diffuse fibrillary astrocytoma. Eleven tumors (14%) could not be classified other than as astrocytoma, "type not otherwise specified." The 10-year overall survival rate for all 79 patients was 50% but significantly differed by histological type: 81% for patients with pilocytic astrocytoma compared to 15% for those with diffuse fibrillary astrocytoma. Tumor grade by the Kernohan, et al., or St. Anne-Mayo methods was also a significant predictor of survival in patients with diffuse fibrillary astrocytoma. The extent of surgical resection (biopsy vs. subtotal resection vs. gross total resection) did not significantly impact survival among patients with pilocytic or nonpilocytic astrocytomas of the spinal cord, although there was a trend toward poorer survival in patients undergoing some degree of resection as opposed to biopsy. Postoperative radiation therapy improved survival but did so more for diffuse fibrillary astrocytoma than pilocytic astrocytoma. In this series, histological type was the most significant predictor of survival in patients with astrocytoma of the spinal cord. The survival rate was highest in patients who underwent biopsy followed by postoperative radiation therapy.

Adult↗
PubMed1995

Cervical disk prolapse.

OBJECTIVE: To correlate the findings on computed tomographic myelography (CTM) with surgically and pathologically proven prolapsed cervical disks, mention other pertinent cross-sectional imaging studies, and note the clinical relevance of certain CTM features. DESIGN: We retrospectively reviewed the medical and radiologic records of Mayo patients with suspected degenerative cervical disk disease during a 4-year period. MATERIAL AND METHODS: Between January 1986 and December 1989, 734 patients with possible cervical disk disease underwent assessment by CTM. An extruded disk was noted in 297 of these patients. In this study group, magnetic resonance (MR) imaging was also done in 28 patients and plain computed tomography was performed in 14, and we summarized those findings. RESULTS: Of the 297 study patients, 280 had a cervical radiculopathy and 17 had a myelopathy. CTM identified more than 90% of the extruded cervical disks. CTM could not distinguish between an osteophytic cartilaginous cap and a disk, and CTM could not identify the source of a cervical radiculopathy in 102 patients. Although only a few imaging studies other than CTM were performed, those modalities were less sensitive in the detection of prolapsed disks. CONCLUSION: Imaging of cervical disk prolapse continues to be difficult, and the results are not always specific. CTM is the most sensitive imaging examination, but the number of MR studies in the current series of patients was insufficient for a reasonable comparison between the two modalities.

Adult↗
PubMed1994

Cervical spondylotic stenosis and myelopathy: evaluation with computed tomographic myelography.

OBJECTIVE: To determine which components of cervical spondylosis are most frequently present in patients with myelopathy. DESIGN: We reviewed the findings in 93 patients who underwent surgical decompression for cervical spondylotic myelopathy between January 1986 and December 1989 at Mayo Clinic Rochester. MATERIAL AND METHODS: All 93 patients (72 men and 21 women) underwent computed tomographic (CT) myelography. In addition, magnetic resonance imaging scans were available in 25 patients, and plain CT scans were obtained in 2. RESULTS: A review of CT myelograms revealed that all neurocompressive intraspinal spondylotic changes were reflected in the shape of the spinal cord. Among the 93 patients with myelopathy, the configuration of the spinal cord could be categorized into primarily three dominant types: A (severe encroachment that compressed the cord into the shape of a banana; N = 40), B (moderate encroachment that produced less prominent compression; N = 23), and C (moderate bilateral uncovertebral spurs; N = 12). As a comparison group, 30 patients with similar spinal cord deformities but without progressive myelopathy were analyzed. Correlation of the two groups showed that myelopathy was present in up to 98% of patients with type A spinal cord, in 75% with type B, and in 71% with type C. The findings on magnetic resonance imaging were similar to those on CT myelography, but the bony spondylotic components were less readily seen. CONCLUSION: The precise pathophysiologic mechanism of myelopathy in spondylosis remains an enigma. Although the bulk of the data on our patients supports direct compression, we believe that the cause is multifactorial.

Adult↗
PubMed1994

Transdural approach to the anterior spinal canal in patients with cervical spondylotic myelopathy and superimposed central soft disc herniation.

We present seven patients with multilevel cervical spondylotic myelopathy and superimposed midline soft disc herniation who were treated by decompressive laminectomies of the spondylotic segments followed by transdural excision of the anteriorly located disc extrusion. There was no perioperative neurological morbidity or mortality associated with this operation, and no patients have developed postoperative kyphotic deformity with an average follow-up of 50.1 months (range, 24 to 87 mo). Two patients had full neurological recovery, whereas five patients had improvement in their preoperative neurological status. We conclude that a posterior transdural approach may offer an alternative surgical option for select patients with multilevel cervical spondylosis with superimposed midline soft disc herniation in whom multiple segment decompression plus access to the anterior spinal canal is necessary.

Adult↗
PubMed1994

Spinal canal stenosis with hypophosphatemic vitamin D-resistant rickets: case report.

A 42-year-old woman with sex-linked hypophosphatemic vitamin D-resistant rickets presented with a 6-month history of progressive weakness and numbness in her lower extremities. Radiological studies revealed severe spinal canal stenosis extending from levels T4 to T10. Her symptoms improved markedly after extensive thoracic laminectomies.

Adult↗
PubMed1994

Pneumatic nerve root compression: epidural gas in association with lateral disc herniation. Report of two cases.

Extreme lateral disc herniations are increasingly recognized as a cause of lumbar nerve root compression syndromes. This disorder often presents major diagnostic and therapeutic challenges, especially in the presence of multiple degenerative changes and chronic back pain in elderly patients. The authors describe two patients with presentations and findings that have not been previously described in the literature. Both patients had histories of upper lumbar back and leg pain. Degenerative spine disease, gaseous degeneration of the intervertebral discs, and epidural gas in the lateral recesses were noted on imaging studies. However, because both patients had undergone prior epidural diagnostic and therapeutic procedures, the epidural gas in the lateral recesses could be attributed either to gaseous disc degeneration or to the previous intraspinal procedures. One patient was found to have a large, far lateral extruded disc fragment that contained air. The nerve root in the second patient was impaled by an unusual combination of a small extruded disc fragment as well as an air-filled sac that was surrounded by the walled-off fragment's capsule and which freely communicated with the gaseous degenerated disc space. The suspected mechanism of root compression is illustrated and discussed. The possibility of disc herniation should be seriously considered in cases of nerve root compression in which epidural gas is present, especially those associated with gaseous degenerated discs.

Aged↗
PubMed1993

Comprehensive study of diagnosis and treatment of trigeminal neuralgia secondary to tumors.

Among 5,058 patients seen at the Mayo Clinic from 1976 through 1990 for face pain, we diagnosed trigeminal neuralgia in 2,972. Tumors were causing the face pain in 296 patients. Sex and pain distributions paralleled those in idiopathic trigeminal neuralgia; however, patients with tumors causing trigeminal neuralgia were younger than those with idiopathic pain. Meningiomas and posterior fossa tumors were the most common. Neurologic deficits developed on follow-up evaluation in 47% of the patients, often precipitating further study and eventual diagnosis of the tumor. Delay in tumor diagnosis averaged 6.3 years. CT with contrast was the most frequently used initial diagnostic radiographic technique, detecting a tumor in 40 of 43 examinations. MRI was subsequently used to confirm and better delineate the tumor in five of five cases. Carbamazepine was the most effective drug for relieving trigeminal neuralgia, but relief was usually temporary. Of the surgical treatment options, total removal of the tumor was the most effective in completely relieving tic pain. In patients at high surgical risk, however, temporarily or permanently blocking afferent impulses with radiofrequency ablation, glycerol rhizotomy, or alcohol blocks was a good alternative to craniotomy.

Brain Neoplasms↗
PubMed1993

The natural history and management of symptomatic and asymptomatic vertebral hemangiomas.

Fifty-nine cases of vertebral hemangioma were seen at the Mayo Clinic between 1980 and 1990. Vertebral hemangiomas were discovered incidentally in 35 patients, while pain was the presenting complaint in 13 patients. Five patients presented directly with progressive neurological deficit requiring surgery, and six patients had surgery elsewhere for spinal cord compression and were referred for follow-up evaluation. To better define the natural history of these lesions, a historical review of these patients was conducted; progression of an asymptomatic or painful lesion to neurological symptoms was found in only two cases (mean follow-up period 7.4 years, range 1 to 35 years). New-onset back pain followed by subacute progression (mean time to progression 4.4 months, range 0.25 to 12 months) of a thoracic myelopathy was the most common presentation for patients with neurological deficit. Initially, all 11 patients with spinal cord compression underwent decompressive surgery with full neurological recovery. Recurrent neurological symptoms were observed in three of six patients following subtotal tumor resection and postoperative administration of 1000 cGy or less radiation therapy (mean follow-up period 8.7 years, range 1 to 17 years). No recurrences were noted in four patients who had subtotal excision plus radiotherapy between 2600 and 4500 cGy. One other patient had gross total tumor removal without radiotherapy and has not had a recurrence. Based on these patients and a review of the literature, the authors recommend annual neurological and radiological examinations for patients with hemangiomas associated with pain, especially young females with thoracic lesions in whom spinal cord compression is most likely to develop. Radiation therapy or embolization is an effective therapeutic alternative for patients with severe medically refractory pain. Regular follow-up monitoring for patients with asymptomatic lesions is unnecessary unless pain develops at the appropriate spinal level. It is concluded that management of patients with a progressive neurological deficit should include preoperative angiography and embolization, decompressive surgery with the approach determined by the degree of vertebral involvement and site of spinal cord compression, and postoperative radiation therapy in patients following subtotal tumor removal. Operative management and complications are discussed.

Adolescent↗
PubMed1993

Cervical neural foraminal canal stenosis: computerized tomographic myelography diagnosis.

The surgical and computerized tomographic myelography (CTM) features of 134 stenotic foraminal canals were correlated retrospectively in 95 patients. The myelographic site of stenosis was the entrance to the foraminal canal in 70 cases (52%) and the canal itself in 37 (28%); the site was not identified definitively in 27 (20%). At the entrance to the foraminal canal, encroachment on the adjacent nerve root was by a cartilaginous cap in 10 cases (8%), a bony osteophyte in 17 (13%), a synovial cyst in one (1%), and a combination of a bony and cartilaginous osteophyte in 42 (31%). The diagnostic features of stenosis within the foraminal canal were more variable. Small bone spurs arising from the uncovertebral process encroached on the anterior aspect of the foramen in 29 instances (22%), accompanied in all cases by either a congenitally narrow canal (in 16) or a diffuse osteophytically narrowed canal (in 13); osteophytes arising from the superior facet in eight instances (6%) were larger and encroached on the posterior aspect of the foramen. Diagnosis on the basis of CTM is difficult because stenosis was readily evident as a bone spur in only 13% of cases, could not be distinguished from prolapsed disc in 39%, had to be differentiated from a congenitally narrow foraminal canal in 27%, and was frankly missed in 20% of the instances of stenosis.

Adult↗
PubMed1991

Extraosseous spinal chordoma. Case report.

An extraosseous extradural tumor of the lumbar region with the histological appearance of chordoma produced symptoms in a 58-year-old woman. The tumor occupied the epidural space and produced scalloping of the adjacent vertebral body and pedicle without associated bone destruction. The location of the tumor within Batson's plexus and lack of osseous connection facilitated complete removal. Although the lesion exhibited the classic histological features of a chordoma, it differed significantly in its extraosseous location. Like the rare intradural chordoma arising in the cranium, this tumor presumably represents neoplastic development in an extraosseous notochordal rest.

Chordoma↗
PubMed1990

Incidence of lumbar disc surgery. A population-based study in Olmsted County, Minnesota, 1950-1979.

Age- and sex-specific incidence rates of operation for suspected lumbar disc prolapse were determined for residents of Olmsted County, Minnesota, for the 30-year period 1950 through 1979. The incidence rate (adjusted to the age and sex distribution of the United States white population in 1980) was 52.3 per 100,000 person-years for all such operations and 46.3 per 100,000 person-years for initial operations. These rates remained fairly constant over the study period. A distinction was made between surgically proven and unproven cases of lumbar disc prolapse. Patients with a surgically proven lumbar disc prolapse had about 10 times the risk of another operation for disc prolapse within 10 years after the first operation compared with the general population.

Adolescent↗
PubMed1990

Calcifying pseudoneoplasms of the neural axis.

An unusual fibrocalcifying lesion of the neural axis was identified in 14 cases. The radiographic appearance was that of a mass, which in some instances was calcified. The surrounding structures were compressed and the adjacent bone was involved. Histologically, the process was basically a granulomatous one. The granulomas were either nodular or confluent, producing a large mass with peripheral lobular configuration. Epithelioid cells and giant cells bordered the granulomas. Most of the granulomas were composed of fibrochondrocalcifying material. The lesion was particularly dangerous when located in a strategic site, such as the foramen magnum or the base of the skull. Two of the 14 patients with this pseudotumor died, and the other 12 have done well. Complete ablation, marginal or even intralesional, assures control of the lesion. The lesion is probably reactive rather than neoplastic.

Adult↗
PubMed1990

Long-term pain relief produced by intrathecal morphine infusion in 53 patients.

The present report details the characteristics of the analgesic effects of morphine administered chronically by infusion pumps implanted in 53 patients suffering from terminal metastatic disease. The median postimplant survival time in these patients was 4 months. Patients (mean age 58 years) were characterized according to the duration of pain before pump implantation (mean 16 months), prior consumption of systemic opioids (mean one to six daily analgesic equivalents of morphine), and their response to a trial intrathecal dose of morphine (1 to 2 mg). The median infusion dose at 2 weeks was 3.8 mg/day. The analgesic index, calculated as (quality of pain relief x duration of pain relief in hours)/morphine dose in mg, that was observed after the trial dose of morphine was determined for each patient. A close correlation was observed between the acute (2-week) infusion dose necessary to produce pain relief and the analgesic index such that the infusion dose = -8.0 x log (analgesic index) + 17.1. By 16 weeks, the mean spinal morphine dose for the group had increased by a factor of about 2.5; however, significant variation in the dose incrementation was documented. The maximum increase was observed in patients with a low analgesic index, and this rapid incrementation was usually correlated with an unsatisfactory overall outcome. Evidence that long-term infusion continues to yield analgesia was evidenced in six cases where there was an unanticipated loss of drug infusion and a corresponding increase in parenteral narcotic consumption. These data indicate the long-term efficacy and safety of spinal opioid infusion in patients with terminal cancer, and emphasize the advantage of assessing the sensitivity of the patient to spinal opioids by a standardized trial injection prior to pump placement as a prognostic indication of outcome.

Adult↗
PubMed1990

An anterior approach for decompression of the suprascapular nerve.

In an effort to increase the beneficial results from decompressive surgery for suprascapular nerve entrapment, an anterior approach has been developed which minimizes manipulation of the suprascapular nerve and maximizes visualization while the decompression is being carried out. The technique and results in three patients are described.

Adult↗
PubMed1989

Magnetic resonance imaging of the spine.

Magnetic resonance (MR) imaging offers the advantages of multiplanar capabilities, physiologic as well as anatomic imaging, and some tissue specificity. Since mid-1985, we have performed more than 2,800 MR examinations of the spine, and gadolinium has been used as a contrast agent in many MR studies since its release by the Food and Drug Administration last year. Although MR imaging has been promoted as the procedure of choice for all clinical indications, on the basis of our experience myelography still plays an important role in the imaging of many spinal disorders, including disk disease. Some pathologic conditions such as intraspinal vascular malformations and leptomeningeal metastatic lesions are best imaged by myelography. MR studies have been most useful in evaluating intraspinal neoplasms, spinal cord parenchymal lesions, infections, congenital abnormalities, and "postoperative failed back syndromes."

Humans↗