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Arnold H Menezes

Publications and source records attributed to Arnold H Menezes.

At least 19 recordsLinked to original sources
PubMed2006

Intentional avulsion fracture of the second cervical vertebra in a hypotonic child.

Children uncommonly present with cervical fractures due to high-impact injuries. A 4-year-old child with developmental delay and chronic hypotonia presented to the hospital with acute onset of irritability and transient difficulty in walking. Lateral neck x-rays showed avulsion fracture of the second cervical vertebra. Neck magnetic resonance imaging study showed injury to the interspinal ligaments between the first and second cervical vertebrae in addition to confirming the acute avulsion fracture of C-2. The child was injured after he was thrown onto a bed from a distance of 1 to 2 ft according to his babysitter's admission. This is the first reported pediatric case presenting this type of inflicted fracture in a hypotonic child, although hypotonia may not have played a causal role.

Cervical Vertebrae↗
PubMed2006

Spinal neurenteric cysts in the magnetic resonance imaging era.

OBJECTIVE: Neurenteric cysts are derived from displaced entodermal tissue. They are infrequently found in the ventral spinal canal with varying degrees of success in their removal. Experience with 10 such individuals is critically analyzed to aid in the diagnosis and management. METHODS: Ten patients, ages 4 through 55 years, with neurenteric cysts were encountered in the last 20 years. This series included three females and seven males; seven children and three adults. The follow-up periods ranged from 3 to 18 years. Three cysts were located at the ventral cervicomedullary junction, five in the midventral cervical spine, and one thoracic and one lumbosacral. The symptoms reflected the location. RESULTS: Six of the 10 patients had associated bony abnormalities such as bifid clivus, hemivertebrae, segmentation failures at the site of the lesion, and blocked vertebra. The patient with the thoracic spinal lesion (age, 55 yr) had symptoms from early childhood. A diplomyelia at the site of the lesion was seen in one individual and tethered spinal cord in the same adult and in a young child. Two patients had undergone laminectomy for aspiration and partial resection before referral to our institution at the time of recurrence. Cervicomedullary junction lesions were approached via the far lateral transcondylar approach; two of the cervical intramedullary lesions were resected via a ventral corpectomy with radical resection and interbody fusion. The goal in each case was complete resection to avoid recurrences. CONCLUSION: Spinal neurenteric cysts are ventrally located, usually intradural and extramedullary, but may insinuate into the spinal cord. They are isointense on T1 images and hyperintense on T2-weighted images on magnetic resonance imaging without true enhancement. These lesions may be associated with block and hemivertebrae with a predisposition to the craniocervical region. Partial resections have led to recurrence and arachnoiditis.

Adolescent↗
PubMed2005

Syringobulbia in a pediatric population.

OBJECTIVE: To better understand the presentation, management, and outcome of syringobulbia in the pediatric age group. METHODS: The University of Iowa pediatric neurosurgery database was searched for patients under the age of 18 with a diagnosis of syringobulbia. The patients' records were retrospectively reviewed for demographic data, chief complaint and presenting symptoms, neurological and radiographic findings, treatment, outcome, and complications. Children with open neural tube defects and Chiari II malformations were excluded. RESULTS: Six pediatric patients were identified as meeting inclusion criteria. The average age at time of surgery was 14.8 years. The chief complaints were vision impairment in three children and numbness, gait instability, and headache worsened with Valsalva in one patient each. Other prominent symptoms included sleep apnea and weakness. All patients showed at least one cranial nerve dysfunction. Radiographs revealed hindbrain herniation and associated syringomyelia in all cases. Two patients had scoliosis. Treatment was posterior fossa decompression with cerebellar tonsillar shrinkage, opening of foramen of Magendie, and duraplasty. Two patients also required concomitant ventral decompression. The cavity of syringobulbia communicated with syringomyelia and the fourth ventricle in most children but was distinct from the fourth ventricle. Two patients received fourth ventricle to subarachnoid shunts. Follow-up averaged 3.2 years, and all patients clinically improved after surgery. Magnetic resonance imaging documented resolution of syringobulbia in all cases, with syringomyelia improving in all cases. There was no permanent morbidity or mortality in the series. CONCLUSION: Syringobulbia is strongly associated with Chiari malformation and syringomyelia, and patients often present because of cranial nerve palsies. Posterior fossa decompression is a safe and effective treatment.

Adolescent↗
PubMed2005

Significant scoliosis regression following syringomyelia decompression: case report.

We present the case of a 5-year-old boy presenting with a 54-degree scoliosis secondary to a Chiari I malformation with a holocord syringomyelia extending from C1 to T10. Neurosurgical treatment involved posterior fossa craniectomy with decompression, and partial C1 laminectomy. At follow-up 7 years later, at age 12, radiographs revealed only a 4-degree scoliosis, and follow-up MRI revealed a deflated syrinx. We report this case to reveal the most significant scoliosis regression seen in our experience that may occur in younger patients after neurosurgical syringomyelia decompression for Chiari I hindbrain herniation.

Cervical Vertebrae↗
PubMed2004

Evaluation and treatment of congenital and developmental anomalies of the cervical spine. Invited submission from the Joint Section Meeting on Disorders of the Spine and Peripheral Nerves, March 2004.

Congenital and developmental osseous abnormalities of the cervical spine can result in neural compression ranging from the medulla oblongata to the cervicothoracic spinal cord junction. These may present in infancy as scoliosis and even limb weakness. A high index of suspicion is essential. Neurodiagnostic imaging relies on high-resolution computerized tomography (CT) scanning and three-dimensional CT reconstructions as well as magnetic resonance imaging and angiography. The anatomical/physiological CT factors considered when developing a surgical approach are: 1) the stability and reducibility of the lesions; 2) direction and manner of encroachment of the lesion on the neural structures; 3) neural and vascular abnormalities; and 4) growth potential of the affected area. Primary stabilization is required for reducible lesions, whereas irreducible lesions are decompressed in the manner in which encroachment has occurred. Instability, whether present before or after operative intervention, required spinal stabilization. Illustrative examples of this approach are presented.

Adolescent↗
PubMed2003

Pediatric spinal deformities.

Pediatric spinal deformity results from multiple conditions including congenital anomalies, neuromuscular disorders, skeletal dysplasia, and developmental disorders (idiopathic). Pediatric spinal deformities can be progressive and cause pulmonary compromise, neurological deficits, and cardiovascular compromise. The classification and treatment of these disorders have evolved since surgical treatment was popularized when Harrington distraction instrumentation was introduced. The advent of anterior-spine instrumentation systems has challenged the concepts of length of fusion needed to arrest curvature progression. Segmental fixation revolutionized the surgical treatment of these deformities. More recently, pedicle screw-augmented segmental fixation has been introduced and promises once again to shift the standard of surgical therapy. Recent advances in thoracoscopic surgery have made this technique applicable to scoliosis surgery. Not only has surgical treatment progressed but also the classification of different forms of pediatric deformity continues to evolve. Recently, Lenke and associates proposed a new classification for adolescent idiopathic scoliosis. This classification attempts to address some of the shortcomings of the King classification system. In this article the authors review the literature on pediatric spinal deformities and highlight recent insights into classification, treatment, and surgery-related complications.

Adolescent↗
PubMed2003

Spinal congenital dermal sinuses: a 30-year experience.

OBJECTIVE: Dermal sinus tracts are an uncommon form of spinal dysraphism often presenting in childhood with skin findings, neurologic deficit, or infection. We reviewed our surgical experience, examining presenting symptomatology, operative findings, and patient outcomes. METHODS: A retrospective analysis of operated dermal sinus tract cases by the senior author (A.H.M.) from 1970 to present was made. RESULTS: Twenty-eight patients were identified; 17 female and 11 male. Five cervical, 4 thoracic, 9 lumbar, and 9 lumbosacral tracts were explored. Sixteen patients presented at <1 year of age, and 12 were >1 year. Reasons for referral included cutaneous findings (15), neurologic deficit (8), foot abnormalities (4), infection (3), pain (2), and scoliosis (1). Our initial examination revealed cutaneous findings (eg, sinus ostea, pigmentation changes, erythema, skin tags, subcutaneous masses) in 27 patients and neurologic deficit in 19. Age-related differences were apparent. Patients >1 year were more likely to have neurologic deficit (92%) as compared with those <1 year (50%). Bifid spinous processes were noted at dural tract entry in 17 patients. Twenty-two tethered cords, 14 inclusion tumors, and 6 patients with evidence of arachnoiditis were found intraoperatively. Mean follow-up was 33 months. Eleven (39%) remained neurologically intact, 12 (43%) improved, 2 (7%) were unchanged, and 3 (11%) were worse with 2 having decreased perianal sensation and 1 slightly worsened motor function postoperatively. CONCLUSIONS: Although most patients were referred for cutaneous stigmata evaluation, >50% had neurologic deficit, intradural tumors, or tethered cords. Skin findings identification should initiate prompt radiologic evaluation and neurosurgical intervention with intradural exploration. Timely intervention may preserve or improve neurologic function in these patients.

Adolescent↗
PubMed2002

Intracranial ependymomas: an analysis of prognostic factors and patterns of failure.

From 1965 to 1997, 49 patients were diagnosed and treated for intracranial ependymoma at one institution. Tumor location was infratentorial in two thirds, and pathology was low grade in 38 patients (78%). Gross total resection of the primary tumor was achieved in 21 (43%). Thirty-six patients received adjuvant radiotherapy; the entire neuraxis was treated in 14, whole brain in 10, and local field only in 12. Median follow-up was 9.6 years (range, 2-33 years). The 5-, 10-, and 15-year overall survival rates were 71.4%, 63.5%, and 63.5% for craniospinal radiotherapy, 60.0%, 60.0%, and 40.0% for whole brain radiotherapy, and 80.8%, 64.6%, and 64.6% for local field radiotherapy (p = 0.88). The 5-, 10-, and 15-year local control rates were 60.3%, 54.4%, and 48.9%. The prognostic factors for a better local control rate were gross total resection (p = 0.021) and low grade histology (p = 0.031). Seventeen of 43 (39.5%) M0 patients did not respond to treatment; all had local failure and 4 also had a spinal relapse. Spinal relapse developed in 3 of 31 (10%) M0 patients who did not receive spinal radiotherapy, whereas 1 of 12 (8%) who had spinal radiotherapy did not respond to treatment in the spine. The results of this study indicate that local radiotherapy is sufficient for M0 patients with intracranial ependymoma.

Adolescent↗
PubMed2002

Cervical and thoracic dermal sinus tracts. A case series and review of the literature.

Cervical and thoracic dermal sinus tracts (DSTs) account for 1 and 10%, respectively, of all DSTs. Few case reports describe this diagnosis. To characterize this entity, a 30-year retrospective audit was utilized to identify cases. Nine cases were identified, five of which were cervical and four thoracic. Four cases less than 1 year old presented with skin findings and no neurologic deficit. All five cases greater than 1 year old presented with neurologic findings. Initial examination revealed changes in motor function (n = 5), sensation (n = 4), reflexes (n = 5), gait (n = 4) and altered bowel/bladder function (n = 2). Eight patients had cutaneous findings and 7 had bifid spinous processes overlying tract entry into the dura. Operative findings included 6 buckled tethered cords, opacified arachnoid or frank arachnoiditis in 4 patients, 2 tract CSF leaks, 2 split cord malformations and 2 intradural tumors. Mean follow-up was 36 months. All infants remained neurologically intact. Four of the 5 patients greater than 1 year old demonstrated improvement; 1 continued with a stable deficit. This series of cervical and thoracic DSTs highlights the need for close attention to skin lesions in infants and consideration of retethering or tumor in patients with previous resections who deteriorate. Definitive operation including intradural exploration should be performed with the initial operation in an attempt to obviate future complications.

Adolescent↗
PubMed2002

Chiari I malformation in the very young child: the spectrum of presentations and experience in 31 children under age 6 years.

INTRODUCTION: The entity of hindbrain herniation without myelodysplasia in the very young child has been poorly described. A retrospective analysis of children diagnosed with Chiari I malformation (CM I) before their sixth birthday is presented. METHODS: Since 1985, 31 children with CM I (0.3-5.8) years of age have been diagnosed at University of Iowa Hospitals and Clinics. Their records were reviewed for presenting symptoms, signs, radiographic findings, treatment, complications, and outcome. RESULTS: The average age at diagnosis was 3.3 years. Sixteen patients were under age 3. Chief presenting complaints included impaired oropharyngeal function (35%), scoliosis (23%), headache or neck pain (23%), sensory disturbance (6%), weakness (3%), and other (10%). Sixty-nine percent of children under age 3 had abnormal oropharyngeal function. Three patients under age 3 (19%) had undergone fundoplication and/or gastrostomy before diagnosis of CM I. Common physical findings included abnormal tendon reflexes (68%), scoliosis (26%), abnormal gag reflex (13%), and normal examination (13%). Vocal cord dysfunction (26%, all under age 3) and syringohydromyelia (52%) were also seen. Twenty-five patients were treated surgically at our institution with posterior fossa decompression, duraplasty, and cerebellar tonsillar shrinkage. Three patients were lost to follow-up. Ninety-one percent of patients reported improved symptomatology at last follow-up (mean: 3.9 years). Three patients required reoperation for recurrence of symptoms. Syringomyelia improved in all patients. Scoliosis resolved in 2 of 8 patients, improved in 5, and stabilized in 1. There was no permanent morbidity from surgery. DISCUSSION: We show that children with Chiari I abnormality are very likely to present with oropharyngeal dysfunction if under age 3, and either scoliosis or headache or neck pain worsened by valsalva if age 3 to 5. These symptoms are very likely to improve after Chiari decompression, which can be done with low morbidity. CONCLUSIONS: Very young children presenting with oropharyngeal dysfunction, pain worsened by valsalva, or scoliosis should prompt the clinician to consider CM I as a possible cause.

Arnold-Chiari Malformation↗
PubMed1999

Pathogenesis, dynamics, and management of os odontoideum.

Os odontoideum is an uncommon craniovertebral junction (CVJ) abnormality that exists as a separate ossicle apart from a hypoplastic dens. It usually moves with the clivus or the anterior arch of C-1 (dystopic) or rarely with the dens (orthotopic). Its genesis and natural history have been debated, and its proper treatment remains uncertain. Two hundred and sixty patients, with symptomatic os odontoideum, were evaluated by the author over a 20-year period; the author performed surgery in 134 of these patients. In a prospective study the author evaluated the early childhood history of trauma, the dynamic studies of motion, and the effects of traction by using pleuridirectional tomography, computerized tomography (CT), CT myelography and magnetic resonance (MR) imaging. Operative findings were documented. Early childhood trauma to the CVJ was recorded in 74 patients, in 30 of whom normal odontoid processes were documented at initial examination prior to the patient reaching age 4 years. Acute neurological deterioration following trauma occurred in 63 of 134 patients. Symptoms were insidious in 71 of 134 patients. In six patients, who presented with acute neurological deterioration after trauma and in whom an abnormal spinal cord signal in the cervicomedullary junction was demonstrated on MR imaging, normal CVJ motion dynamics were shown. Motion dynamics varied and were unique to each patient. Irreducible ventral CVJ disease causing cervicomedullary compromise occurred in 28 patients in whom a transpharyngeal ventral decompressive procedure was necessitated. During the transoral operation, the transverse portion of the cruciate ligament was found to be located anterior to the axis body. All patients required dorsal CVJ arthrodesis, which, in 46, was limited to the C1-2 segment. Instability at the C1-2 joints was always multidirectional, as demonstrated on preoperative neuroimaging studies as well as at operation. Sixteen patients presented after completed primary C1-2 dorsal fusion and with worsening deficits. They improved when the range of the fusion was extended to the occiput or if the ventrally located lesion was excised. Os odontoideum is associated with early childhood trauma and is an acquired phenomenon. The presence of abnormal motion dynamics necessitates surgical intervention as do associated neurological deficits. Asymptomatic patients in whom os odontoideum is incidentally discovered and in whom no abnormal motion dynamics are demonstrated should be followed closely.

Journal Article↗
PubMed1999

Instability of the craniovertebral junction and treatment outcomes in patients with Down's syndrome.

Operative intervention for the treatment of instability at the craniovertebral junction in patients with Down's syndrome has become somewhat controversial because some authors have reported high surgery-related complication rates and suggested that the incidence of neurological abnormality associated with this abnormal motion may be low. In this report, the authors describe the clinical and radiographic findings in 33 patients treated at their institution. Common presenting symptoms included neck pain (14 patients), torticollis (12 patients), and myelopathy manifested as hyperreflexia (21 patients), or varying degrees of quadriparesis (11 patients). Four patients suffered acute neurological insults, two after receiving routine general anesthetics for minor surgical procedures and two other patients following minor falls. Atlantoaxial instability was the most common abnormality documented on radiography (22 patients). Atlantooccipital instability (15 patients) was also frequently observed and was coexistent with the presence of atlantoaxial luxations in 14 patients. A rotary component of the atlantoaxial luxation was present in 13 cases. In 17 patients bony anomalies were present, the most frequent of which was os odontoideum (10 patients). Twenty-four patients underwent operative intervention, and successful fusion was achieved in 23. In six of nine patients with basilar invagination, reduction was achieved with preoperative traction and thus avoided the need for ventral decompressive procedures. There were no cases of postoperative deterioration, and 22 patients made excellent or good recoveries. The results of this series highlight the clinicopathological phenomena of craniovertebral instability in patients with Down's syndrome and suggest that satisfactory outcomes can be achieved with a low rate of surgical morbidity.

Journal Article↗