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Biomedical subjects

G I Jallo

Publications and source records attributed to G I Jallo.

At least 19 recordsLinked to original sources
PubMed2004

Toxicity and cerebrospinal fluid levels of carboplatin chronically infused into the brainstem of a primate.

PURPOSE: Carboplatin was infused into the brainstem of cynomolgus monkeys to investigate neurotoxicity and systemic exposures following chronic local delivery. METHODS: Infusions at 0.42 microl/h were intended to deliver 0.025 (n = 2), 0.075 (n = 3), 0.25 (n = 5), and 0.75 (n = 3) mg/kg by day 30. Laboratory tests, radiographic measurements, and clinical observations were used to monitor toxicity. Blood and cerebrospinal fluid (CSF) were sampled for platinum. RESULTS: Lethargy and ataxia were observed after week 4 in the monkeys given 0.075 mg/kg, and week 2 in the monkeys given 0.25 mg/kg when the infused doses were approximately 250 and 400 microg, respectively. Rapidly progressive neurotoxicity with the 0.75 mg/kg dose required termination of the infusions at days 4-10. Hematology and chemistry values were unremarkable in all groups. Blood levels of platinum remained undetectable in 0.025 and 0.075 mg/kg dose groups. Levels in the 0.25 mg/kg group were 3.1 +/- 0.6 microg/l at 2 weeks and 5.2 +/- 0.8 microg/l at 1 month. The CSF platinum levels varied. Animals in the 0.25 mg/kg group had higher CSF levels at 2 weeks (avg. 65 microg/l, range 36-89) compared to their 1 month value (avg. 60 microg/l, range 7-170), despite the constant infusion. CONCLUSION: Carboplatin can be chronically infused into monkey brainstems. Neurotoxicity is the predominant side effect and is dose-dependent. Pharmacokinetics of local and systemic delivery are different for carboplatin. Further studies are needed to monitor toxicity at higher flow rates and to investigate drug binding to abnormal central nervous system (CNS) tissues.

Animals↗
PubMed2001

Pediatric intramedullary spinal cavernous malformations.

STUDY DESIGN: A retrospective analysis of a large single institution pediatric intramedullary tumor database. The database was searched for all pediatric intramedullary cavernous malformations. OBJECTIVES: To review the authors' experience with three pediatric intramedullary cavernous malformations, review the previous literature, and discuss the surgical management for these rare lesions. SUMMARY OF BACKGROUND DATA: Cavernous malformations can occur throughout the central nervous system; however, the intramedullary spinal cord is a rare location. More recent estimates indicate that cavernous malformations constitute 5% of all vascular malformations. There is no series that reports the management of pediatric intramedullary cavernous malformations. METHODS: There were 181 pediatric intramedullary lesions in the tumor database. A review revealed three children with a mean age of 13.3 years (range, 8-19 years) with intramedullary cavernous malformations. All these children presented with an acute motor deficit that prompted radiographic imaging and diagnosis. All the children underwent laminectomy and gross total removal of the lesion. All the malformations abutted the dorsal pial surface and created a blue discoloration, which was evident after opening the dura. RESULTS: Approximately 10% of all intramedullary cavernous malformations present in the pediatric population. Pediatric lesions, unlike those in adults, have an acute presentation, and the lesions are typically found in the cervical region. The surgical removal of these malformations results in a good functional outcome. The entire neuraxis should be screened because there is a high incidence of multiple lesions. CONCLUSIONS: The surgical removal of these malformations results in a good functional outcome. The entire neuraxis should be screened because there is a high incidence of multiple lesions.

Adolescent↗
PubMed2001

Treatment of Chiari I malformation in patients with and without syringomyelia: a consecutive series of 66 cases.

OBJECT: The authors describe the results of performing a standard posterior craniovertebral decompression and placement, if indicated, of a syringosubarachnoid shunt for the treatment of patients with Chiari I malformation with and without syringomyelia. METHODS: This is a retrospectively analyzed consecutive series of 66 patients (mean patient age 15 years, range 1-53 years). The uniform posterior craniovertebral decompression consisted of a small suboccipital craniectomy, a C-1 laminectomy, microsurgical reduction of the cerebellar tonsils, and dural closure with a synthetic dural graft to increase the cerebrospinal fluid space at the craniocervical junction. The presence of a large syrinx, with significant thinning of the spinal cord tissue and obliteration of the spinal subarachnoid space, particularly when combined with syrinx-related symptoms, was an indication for the placement of a syringosubarachnoid shunt. In 32 patients Chiari I malformation alone was present, and 34 in patients it was present in combination with syringomyelia. Clinical findings included pain, neurological deficits, and spinal deformity. The presence of syringomyelia was significantly associated with the presence of scoliosis (odds ratio 74.4 [95% confidence interval 8.894-622.4]). All patients underwent a posterior craniovertebral decompression procedure. In 22 of the 34 patients with syringomyelia a syringosubarachnoid shunt was also placed. The mean follow-up period was 24 months (range 3-95 months). Excellent outcome was achieved in 54 patients (82%) and good outcome in 12 (18%). In no patient were symptoms unchanged or worse at follow-up examination, including four patients who initially required a second operation for persistent syringomyelia. Pain was more likely to resolve than sensory and motor deficits after decompressive surgery. Radiological examination revealed normalization of tonsillar position in all patients. The syrinx had disappeared in 15 cases, was decreased in size in 17, and remained unchanged in two. CONCLUSIONS: Posterior craniovertebral decompression and selective placement of a syringosubarachnoid shunt in patients with Chiari I malformation and syringomyelia is an effective and safe treatment. Primary placement of a shunt in the presence of a sufficiently large syrinx appears to be beneficial. The question of if and when to place a shunt, however, requires further, preferably prospective, investigation.

Adolescent↗
PubMed2001

Intramedullary low-grade astrocytomas: long-term outcome following radical surgery.

The management of low-grade intramedullary astrocytomas is controversial. Unlike ependymomas, which have a distinct cleavage plane, astrocytomas are diffuse infiltrative tumors. The intramedullary tumor database at NYU Medical Center was searched to identify all patients with intramedullary astrocytoma from 1988 to 1994. Seventeen patients presented with a low-grade diffuse astrocytoma. The medical, surgical and office records were reviewed retrospectively and statistically analyzed. All patients underwent a radical resection of the intramedullary tumor; of these, 12 patients had gross-total removal and 5 had subtotal removal. Nine patients received adjuvant radiotherapy. The median follow-up period was 7.4 years. Fourteen patients are alive and have stable disease. Eleven patients (79%) are functionally independent at last follow-up. The remaining patients are at functional Grade III. The 5-year overall survival was 82% for this group. These results indicate that aggressive surgery is associated with a prolonged survival for patients with intramedullary astrocytomas. Radiation therapy should only be reserved for patients who have radiographic progression or inoperable disease.

Adult↗
PubMed2001

Infrasellar craniopharyngiomas: case report and review of the literature.

Although craniopharyngiomas account for a large percentage of pediatric intracranial tumors, there is a bimodal age distribution. Most of these neoplasms are suprasellar or sellar in location. In this report we describe an unusual case of an infrasellar craniopharyngioma in a child. Only four previous cases of infrasellar craniopharyngiomas with no sellar involvement have been described. Infrasellar craniopharyngiomas are part of the continuum representing intracranial craniopharyngiomas and ameloblastomas of the jaw. A transnasal endoscopic biopsy was performed with a preliminary diagnosis of craniopharyngioma. The patient then underwent a radical resection of the infrasellar tumor via a subfrontal transbasal approach. This case illustrates a rare and unusual location for a craniopharyngioma. Craniopharyngiomas should be considered in the differential diagnosis of infrasellar neoplasms. Infrasellar craniopharyngiomas compromise part of the spectrum of tumors originating from enamel-forming neural crest cells.

Case Reports↗
PubMed2001

Intraspinal clear cell meningioma: diagnosis and management: report of two cases.

OBJECTIVE AND IMPORTANCE: Intraspinal clear cell meningioma is a rare morphological variant of meningioma. Only 13 case reports are found in the literature; therefore, no management strategy has been defined for this tumor type. This article describes two patients, reviews the literature, and proposes a treatment plan for clear cell meningioma. CLINICAL PRESENTATION: Two female patients, 22 months and 8 years of age, respectively, presented with localized neck and leg pain that limited their ability to walk. Magnetic resonance imaging revealed intradural tumors, a cervical intramedullary neoplasm in the younger patient, and a cauda equina tumor in the older child. INTERVENTION: Both patients underwent radical resection of their intradural tumor. Both tumors, however, recurred shortly (5 and 6 mo) after the initial operation. During the second operation, a radical removal was performed on each patient. Both patients received adjuvant radiotherapy. In addition, the younger patient developed posterior fossa metastasis 20 months after intraspinal surgery. CONCLUSION: Intraspinal clear cell meningiomas are very uncommon tumors. The clinical course in our two patients supports the reported 40% recurrence rate within 15 months. These tumors also can disseminate within the central nervous system. We recommend serial imaging studies every 3 months. For recurrent tumors, we recommend localized radiation therapy after reoperation.

Child↗
PubMed2001

Surgical management of isolated hemangioblastomas of the spinal cord.

OBJECTIVE: Intramedullary hemangioblastomas are rare tumors, accounting for just 3% of all intraspinal neoplasms. The purpose of this study is to define the occurrence of isolated intramedullary hemangioblastomas and to analyze the role of the radiological studies and surgery for these lesions. METHODS: The charts of 19 consecutive patients operated on for isolated spinal intramedullary hemangioblastoma were reviewed. Preoperatively, all patients underwent magnetic resonance imaging and nine underwent spinal angiography. For all patients, the surgical approach was via posterior laminectomy. RESULTS: Our study sample comprised 6 women and 13 men, with an average age of 31.5 years (range, 16-75 yr). The mean prodrome was 20.8 months. Pain was the most common complaint. In all cases, the neoplasms were associated with a syrinx or edema. Gross total resection was achieved in all patients. At last follow-up examination (mean, 50.1 mo), 13 patients (68%) had improved and 6 patients (32%) had stabilized as compared with their preoperative clinical status. CONCLUSION: Isolated intramedullary hemangioblastomas typically have an indolent clinical course. These tumors have characteristic imaging properties on magnetic resonance imaging and angiography. Surgical removal of these lesions results in excellent long-term functional outcome.

Adolescent↗
PubMed2001

Foreign body reaction to hemostatic materials mimicking recurrent brain tumor. Report of three cases.

Chemical agents routinely used in neurosurgery to achieve intraoperative hemostasis can cause a foreign body reaction, which appears on magnetic resonance (MR) images to be indistinguishable from recurrent tumor. Clinical and/or imaging evidence of progression of disease early after surgical resection or during aggressive treatment may actually be distinct features of granuloma in these circumstances. A series of three cases was retrospectively analyzed for clinical, imaging, surgical, and pathological findings, and the consequences they held for further disease management. All patients were boys (3, 3, and 6 years of age, respectively) and all harbored primitive neuroectodermal tumors. Two tumors were located in the posterior fossa and one was located in the right parietal lobe. Two boys exhibited clinical symptoms, which were unexpected under the circumstances and prompted new imaging studies. One patient was asymptomatic and imaging was performed at planned routine time intervals. The MR images revealed circumscribed, streaky enhancement in the resection cavity that was suggestive of recurrent disease. This occurred 2 to 7 months after the first surgery. At repeated surgery, the resected material had the macroscopic appearance of gelatin sponge in one case and firm scar tissue in the other cases. Histological analysis revealed foreign body granulomas in the resected material, with Gelfoam or Surgicel as the underlying cause. No recurrent tumor was found and the second surgery resulted in imaging-confirmed complete resection in all three patients. Because recurrent disease was absent, the patients continued to participate in their original treatment protocols. All patients remain free from disease 34, 32, and 19 months after the first operation, respectively. During or after treatment for a central nervous system neoplasm, if unexpected clinical or imaging evidence of recurrence is found, a second-look operation may be necessary to determine the true nature of the findings. If the resection yields recurrent tumor, additional appropriate oncological treatment is warranted, but if a foreign body reaction is found, potentially harmful therapy can be withheld or postponed.

Brain↗
PubMed2000

Spinal intramedullary cavernoma: clinical presentation and surgical outcome.

OBJECT: Improved neuroimaging techniques have led to an increase in the reported cases of intramedullary cavernomas. The purpose of this study was to define the spectrum of presenting signs and symptoms in patients with spinal intramedullary cavernomas and to analyze the role of surgery as a treatment for these lesions. METHODS: The authors reviewed the charts of 16 patients who underwent surgery for spinal intramedullary cavernomas. All patients underwent preoperative magnetic resonance imaging studies. Cavernomas represented 14 (5.0%) of 280 intramedullary lesions found in adults and two (1.1%) of 181 intramedullary lesions found in pediatric cases. A posterior laminectomy and surgical resection of the malformation were performed in all 16 patients. CONCLUSIONS: Magnetic resonance imaging is virtually diagnostic for spinal cavernoma lesions. Patients with spinal intramedullary cavernomas presented with either an acute onset of neurological compromise or a slowly progressive neurological decline. Acute neurological decline occurs secondary to hemorrhage within the spinal cord. Chronic progressive myelopathy occurs due to microhemorrhages and the resulting gliotic reaction to hemorrhagic products. There is no evidence that cavernomas increase in size. The rate of rebleeding is unknown, but spinal cavernomas appear to be clinically more aggressive than cranial cavernomas, probably because the spinal cord is less tolerant of mass lesions. Complete surgical removal of the cavernoma was possible in 15 of 16 of the authors' cases.

Adolescent↗
PubMed1999

Propionibacterium as a cause of postneurosurgical infection in patients with dural allografts: report of three cases.

OBJECTIVE AND IMPORTANCE: Although Propionibacterium acnes is a common inhabitant of human skin, it is an uncommon pathogen in postoperative infections. We report three cases of postoperative wound infection/osteomyelitis caused by P. acnes. CLINICAL PRESENTATION: Three patients underwent craniotomy for a supratentorial meningioma and had a dural allograft at the time of closure. The patients presented several weeks after surgery with clinical evidence of a wound infection. INTERVENTION: All patients were diagnosed with P. acnes infection and treated for this pathogen with appropriate antibiotics. The bone flap was removed in two patients. After antibiotic therapy, all patients demonstrated no further evidence of infection. CONCLUSION: To our knowledge, this is the first published report of P. acnes infection in patients with a dural substitute. The source of infection cannot be confidently ascertained; however, two patients had strains of P. acnes from one brand of graft, which were indistinguishable by pulsed field gel electrophoresis typing.

Adult↗
PubMed1999

Aneurysmal bone cyst of the temporal bone.

OBJECTIVE AND IMPORTANCE: Aneurysmal bone cysts (ABC) are benign bone neoplasms which typically involve the spine and long bones. We present a rare case of an ABC in the temporal bone with significant cerebellar compression. CLINICAL PRESENTATION: The patient was a young boy who presented with several weeks of left posterior auricular pain. Computed tomography, magnetic resonance imaging and angiogram showed an expansile bone neoplasm involving the left petrous temporal bone. INTERVENTION: A retrosigmoid-transmastoid craniectomy was performed, and total removal of the bone lesion was achieved. The pathological examination revealed the diagnosis of ABC. CONCLUSION: The postoperative course was uneventful, and the imaging studies demonstrated total removal of the neoplasm. This case represents the imaging and surgical management of a rare ABC in the temporal bone. This diagnosis should be considered in the differential of bone neoplasms in this region.

Bone Cysts, Aneurysmal↗
PubMed1998

Nocardia abscess of the choroid plexus: clinical and pathological case report.

OBJECTIVE: Cerebral Nocardia abscesses are rare, accounting for approximately 1 to 2% of all cerebral abscesses. Prompt aggressive surgical treatment involving craniotomy and excision of these lesions has been advocated by many authors, because these lesions have significantly higher morbidity and mortality rates than do most other cerebral abscesses. We report an atypical presentation of cerebral nocardiosis localized to the choroid plexus of the lateral ventricle. CLINICAL PRESENTATION: A 56-year-old man presented with a 3-week history of fever, cough, and progressive headache and an ensuing 3-day history of progressive lethargy, confusion, and gait ataxia. Radiographic studies demonstrated a loculated contrast-enhancing left lateral ventricular lesion with significant perilesional parenchymal edema that was thought preoperatively to be a neoplasm. INTERVENTION: The patient underwent a craniotomy for resection of the lesion. Intraoperatively, a reddish gray lesion with purulent exudate was encountered within the left lateral ventricle intimately adherent to the choroid plexus as well as to the ependyma and subependymal veins. A frozen section demonstrated an organizing abscess wall. The lesion was resected in its entirety, and multiple cultures were sent for analysis. CONCLUSION: Microbiology cultures grew Nocardia asteroides. A course of intravenous antibiotics was started, which included trimethoprim-sulfamethoxazole, amikacin, and ceftriaxone. Two weeks after surgery, at the time of discharge, the patient's neurological status had improved considerably. Although Nocardia abscesses have been documented to occur throughout the central nervous system, the presentation of a lesion confined to the choroid plexus of the lateral ventricle with significant parenchymal edema is unusual and demonstrates that Nocardia abscesses must be considered in the differential diagnosis of a contrast-enhancing intraventricular mass lesion involving the choroid plexus.

Brain Abscess↗