Respiratory failure caused by Chiari I malformation with associated syringomyelia.

The authors report a case of a 38-year-old male with a Chiari I malformation and syringomyelia that presented with acute respiratory distress. Pulmonary function testing was consistent with respiratory muscle weakness. A suboccipital craniectomy and C1, 2, 3 laminectomies were performed on an emergent basis. Postoperatively the patient had significant improvement in his respiratory status associated with a reduction in the size of the syringomyelia on follow-up imaging.

Cutaneous metastasis of chordoma.

BACKGROUND: Chordomas are rare neoplasms that arise from the notochord remnant. They develop in the sacrococcygeal (50%) or cervical (15%) region and are generally regarded as a locally aggressive tumor with a slow progressive growth rate and a metastatic incidence ranging from 3 to 48%. Skin involvement by chordoma is rare, but can occur by direct extension, by local recurrence and by metastases. OBJECTIVE: To illustrate by a case report the clinical presentation and management of this disease. METHODS: We present a case of sacral chordoma with metastases over a 10-year period to the lungs, the soft tissue of the chest wall, the triceps tendon, and distant cutaneous metastases to the back and the nose. RESULTS: The cutaneous metastases were treated by excision. CONCLUSION: Chordoma is a slow growing tumor of the notochord remnant that may metastasize to the skin. Physicians and pathologists should be aware of this entity.

Visual loss associated with fibrous dysplasia of the anterior skull base. Case report and review of the literature.

The authors present a case of visual loss associated with fibrous dysplasia of the anterior skull base and the surgical management of this case. Preoperative computerized tomography scanning in this patient demonstrated a patent optic foramen and a rapidly growing cystic mass within the orbit, which was responsible for the patient's visual loss. A literature review revealed that this case is typical, in that cystic mass lesions of various types are frequently responsible for visual loss associated with fibrous dysplasia. The authors did not find significant evidence in the literature to support the notion that visual loss associated with fibrous dysplasia is the result of progressive optic canal stenosis, thus raising questions about the value of prophylactic optic canal decompression. Instead, as demonstrated by this case and those uncovered in the literature review, most instances of visual loss result from the rapid growth of mass lesions of cystic fibrous dysplasia, mucoceles, or hemorrhage. Findings of the literature review and the present case of fibrous dysplasia of the anterior skull base support a role for extensive surgical resection in these cases and indicate a need for additional prospective analysis of a larger number of patients with this disease.

Outpatient surgical treatment of cervical radiculopathy.

A series of 200 patients who underwent outpatient surgical treatment for cervical radiculopathy is presented. The patients were selected on the basis of their willingness to undergo surgery in the outpatient setting and the absence of serious underlying medical conditions. All operations were performed using general anesthetic techniques with limited posterior dissections. A laminoforaminotomy was performed at each affected level, which had been determined by preoperative imaging and clinical examination. After being observed for several hours, the patients were discharged if they met specific criteria. No patient required subsequent hospital admission in the immediate postoperative period. Follow-up review in 183 patients ranged from 3 to 43 months, with a mean of 19 months. In cases in which Workers' Compensation claims were not involved, 92.8% of patients reported an excellent or good outcome and returned to work or comparable duties at a mean of 2.9 weeks. In cases in which Workers' Compensation claims were involved, 77.8% of patients reported excellent or good outcome and returned to work at a mean of 7.6 weeks postoperatively. Two patients whose cases involved Workers' Compensation claims did not return to work. There were seven patients (3.8%) who had a poor outcome. Two of these patients underwent a second posterior procedure and reported a good outcome at the time of follow-up review. The results of this study show that outpatient surgical treatment of cervical radiculopathy can be safely provided in selected patients with outcomes similar to the inpatient surgical management of these individuals.

Anterior transcranial (craniofacial) resection of tumors of the paranasal sinuses: surgical technique and results.

Transfacial approaches, traditionally used for malignant tumors of the paranasal sinuses, provide limited exposure when several sinuses are involved and are unsuitable for tumors that erode through the floor of the anterior cranial fossa. A transcranial approach may aid in the removal of such lesions. To better understand the risks and benefits of this surgical approach, we reviewed all patients (n = 76) who underwent a transcranial approach as part of the excision of paranasal sinus lesions between 1984 and 1993 at our institution. The spectrum of disease included adenocarcinoma (13 patients), squamous cell carcinoma and olfactory neuroblastoma (11 patients each), adenoid cystic carcinoma and poorly differentiated forms of carcinoma (6 patients each), melanoma (5 patients), and miscellaneous others (24 patients). Most patients had ethmoid sinus involvement; tumors were also commonly found in the cribriform plate, sphenoid sinus, and nasal fossa. In each patient, a bifrontal craniotomy was performed with extradural dissection to the floor of the anterior fossa and osteotomies for resection of involved elements. In 47 patients (62%), disease in the orbit, the anterior nasal cavity, or the soft tissues of the face required transfacial as well as transcranial resections. Bony defect in the anterior fossa floor was repaired with a pedicled pericranial flap. Patients with major complications included six patients with epipericranial and/or epidural hematomas requiring evacuation, three with transient cerebrospinal fluid leaks, two who developed bifrontal cerebral infarcts, and one who died soon after surgery. No meningitis was seen. To date, 26 patients (34%) have died; of those living (mean follow-up, 34 mo), 42 (84%) remain in full remission. The transcranial approach can achieve removal of erosive, invasive tumors from this area with predictable morbidity and may be considered whenever sinus tumors breach the anterior cranial base or extend beyond the reach of conventional transfacial approaches.

Fracture of a sublaminar stainless steel cable in the upper cervical spine with neurological injury. Case report.

Sublaminar cables have been used to stabilize bone grafts for arthrodesis in the cervical spine in recent years. Previous accounts of their use have indicated no instances of breakage or neurological injury. This report is of a delayed cable fracture that resulted in penetration of the dura with neurological injury in a patient who had undergone atlantoaxial fusion for rheumatoid subluxation. The cable fracture occurred in the epidural space beneath the attempted arthrodesis and resulted in uncoiling of the cable, which penetrated spinal canal and caused a one-sided sensory deficit.

Cytokine responses to intraventricular injection of interleukin 2 into patients with leptomeningeal carcinomatosis: rapid induction of tumor necrosis factor alpha, interleukin 1 beta, interleukin 6, gamma-interferon, and soluble interleukin 2 receptor (Mr 55,000 protein).

Interleukin 2 (IL-2) is a potent immunostimulant that causes the release of secondary cytokines and the production of lymphokine-activated killer cells. We investigated the cellular and cytokine responses to injection of recombinant human IL-2 into the human cerebrospinal fluid of 11 patients with metastatic tumors involving the spinal or cerebral leptomeninges. After initial intraventricular IL-2 administration (1.25 x 10(5) to 2 x 10(6) Cetus units/injection), cerebrospinal fluid samples were collected at intervals from 0 to 24 h. Enzyme-linked immunosorbent assay results indicated that IL-2 levels gradually decreased during the first 24 h, with an average t1/2 between 4 and 8 h. Induction of tumor necrosis factor alpha, interleukin 1 beta, interleukin 6, gamma-interferon, and interleukin 2 receptor (p55) was also assessed by enzyme-linked immunosorbent assay. Tumor necrosis factor alpha and interleukin 6 levels peaked at 2 to 4 h and 4 to 6 h, with concentrations between 71 to 1,714 pg/ml and 942 to 10,500 pg/ml, respectively. Interleukin 1 beta, gamma-interferon, and soluble IL-2 receptor peaked later, during 6 to 12 h; the levels achieved were 234 pg/ml, 25 NIH units/ml, and 207 units/ml, respectively. All cytokine concentrations returned to near baseline between 12 and 24 h; however, the soluble IL-2 receptor levels remained elevated. Additional observations included a rapid influx of neutrophilic leukocytes, followed by a prolonged presence of lymphocytes. These data indicate a broad and complex potential of the immune response in the central nervous system, as well as further define the cytokine cascade in response to IL-2 alone.

Transcranial resection of tumors of the paranasal sinuses and nasal cavity.

Combined cranial and facial procedures for resection of malignancies of the paranasal sinuses and nasal cavity have been used with variable success and complication rates in the last 25 years. A series of nine patients undergoing 10 exclusively transcranial procedures for these tumors is presented, and an effective technique for reconstruction without free tissue transfer is described. The patients in this series suffered no major complications, and all have remained free of disease during the short follow-up period. The technique described in this report offers the advantage of wide exposure, symmetrical approach to the superstructures of the face and orbits, the potential for resection of a large portion of the anterior cranial floor, and substantial reconstruction which is a major factor in avoiding complications.

Superselective intra-arterial chemotherapy of advanced paranasal sinus tumors.

Twenty-four patients with advanced paranasal sinus tumors were treated with combined superselective intra-arterial and systemic chemotherapy, yielding an immediate satisfactory tumor response rate of 91%, significantly better than previously reported. Eight patients had craniofacial surgery circumvented because of complete or near complete response. Repetitive uncomplicated catheterization of the pterygoid segment of the internal maxillary artery using a coaxial system is the cornerstone of successful induction chemotherapy. Strenuous screening of medical status is mandatory for this aggressive introduction chemotherapy.

Vascular permeability induced by protein product of malignant brain tumors: inhibition by dexamethasone.

Serum-free conditioned medium derived from confluent monolayer cultures of malignant human astroglial tumors contains a substance that rapidly increases capillary vascular permeability after intradermal injection into guinea pigs. Accumulation of vascular permeability factor (VPF) activity occurs with increasing duration of tumor incubation in vitro. Expression of this activity is inhibited by incubation of cell cultures with cycloheximide or dexamethasone. This VPF is an acid-stable heat-labile macromolecule that is inactivated by trypsin and pepsin and binds immobilized heparin. Activity is retained by ultrafiltration with 30,000-dalton cut-off microconcentrators. Pretreatment of test animals with systemic dexamethasone prior to intradermal injection of VPF diminishes microvascular permeability. Furthermore, VPF activity is not inhibited by antihistamines. Secretion of VPF may cause the vasogenic brain edema that is frequently associated with malignant primary and metastatic intracerebral tumors. Inhibition by dexamethasone of both VPF expression in tissue culture, and VPF activity at the microvascular level in test animals, is in keeping with the known efficacy of this agent in treating the vasogenic edema associated with brain tumors.

Melanoma arising in a spinal nerve root. Case report.

Melanotic neoplasms of the spinal nerve root are rare but well-documented occurrences. The authors report the case of a 68-year-old woman with a malignant melanotic neoplasm containing premelanosomes and melanosomes and lacking a basal lamina. This tumor was found in a lumbar nerve root and is believed to represent an instance of a primary melanoma arising in a spinal nerve root. The differential diagnosis of pigmented lesions of spinal nerve root includes melanoma, pigmented nerve sheath tumor, blue nevus, melanotic clear-cell sarcoma, and meningeal melanocytoma. Surgeons should be aware of the potential for encountering unexpected malignant lesions involving spinal nerve roots.

Carotid artery mixing with diastole-phased pulsed drug infusion.

Focal injury to the brain or retina is a frequent complication of drug delivery to the internal carotid artery (ICA) and may be due to poor mixing of the drug with blood at the infusion site. Rhesus monkeys were studied to determine whether phased drug delivery during diastole from a modified pulsatile angiographic injector would improve drug mixing in vivo. A radiolabeled flow tracer, carbon-14-iodoantipyrine (14C-IAP), was injected into the ICA of three monkeys in 80-msec pulses, each ending at least 50 msec before the end of local diastole. Local isotope concentration in the brain was determined by quantitative autoradiography. The ratio of highest to lowest concentration was 1.86 +/- 0.26 (mean +/- standard deviation) in the frontoparietal cortex, 1.65 +/- 0.42 in the frontoparietal white matter, 1.89 +/- 0.28 in the temporal cortex, and 1.39 +/- 0.17 in the basal ganglia. These results were similar to recordings in three control animals that received intravenous 14C-IAP to demonstrate complete drug mixing (1.37 +/- 0.12, 1.41 +/- 0.11, 1.70 +/- 0.08, 1.22 +/- 0.24, respectively), and contrasted to findings in five animals which received continuous intracarotid infusions to demonstrate standard ICA drug delivery (4.54 +/- 2.07, 2.94 +/- 1.45, 5.43 +/- 3.57, 3.60 +/- 2.90, respectively). Pulsed intra-arterial infusion during diastole provides a technically simple method for improving intravascular drug mixing, and results in drug delivery to tissue capillaries that is proportional to blood flow.

Effect of barbiturate coma on glucose utilization in normal brain versus gliomas. Positron emission tomography studies.

Glucose utilization by normal and neoplastic cerebral tissue can be measured in humans using positron emission tomography (PET) with fluorine-18-labeled 2-deoxy-D-glucose (FDG). Malignant gliomas are known to exhibit hypermetabolic glucose consumption compared to normal brain. Barbiturate-sensitive cerebral glucose utilization is coupled to neuronal activity, and lesions lacking neuronal activity should be relatively insensitive to barbiturate suppression of glucose utilization. In a study to examine this phenomenon, three patients with cerebral gliomas underwent FDG-PET while awake and during deep barbiturate coma. Cerebral glucose utilization was measured in normal brain, tumor, and a homologous, non-neoplastic control site in the contralateral hemisphere. A glucose utilization ratio for tumor/control tissue was calculated. The mean reduction of glucose utilization during barbiturate coma was: gray matter 67%, white matter 47%, basal ganglia 66%, thalamus 57%, cerebellar cortex 55%, tumor 32%, and the contralateral control site 64%. The mean tumor glucose utilization ratio was 1.48:1 in the awake state and 2.69:1 during barbiturate coma. The changes in gray matter, basal ganglia, thalamus, cerebellar cortex, and tumor/control tissue ratio were significant (p less than 0.05). In one patient, deep tumor invasion not evident on computerized tomography, magnetic resonance imaging, or baseline FDG-PET was apparent during barbiturate-enhanced FDG-PET scanning. The study findings suggest that gliomas resist suppression of glucose utilization by barbiturates; this supports the hypothesis that barbiturates reduce neuronal metabolism by blocking synaptic activity. This differential effect on normal brain and gliomas enhances the capability to assess the extent of neoplastic tissue in brain and may represent the basis for novel therapeutic strategies.

Glioblastoma: catheter techniques for isolated chemotherapy perfusion.

Techniques have been developed for isolated perfusion of chemotherapeutic agents in patients with glioblastoma. Three catheters that facilitate crossing the carotid siphon have been developed; two are based on an everting or toposcopic principle, and one uses microjets for deflectability and improved mixing. Blood from the ipsilateral jugular vein is aspirated at high volumes (300 ml/min) for extracorporeal circulation through an adsorption column (for recovery of carmustine) or dialysers (for recovery of cisplatin). Preliminary experience in 10 patients suggests that high doses of chemotherapeutic agent can be administered using these catheters, with reduced retinal and systemic toxicity.

Intrathecal morphine during lumbar spine operation for postoperative pain control.

The analgesic requirements and bladder function of 5 patients who received 1 mg of intrathecal morphine during lumbar spine operation are compared to those of 10 control patients. No analgesics were used by the treatment group for the first 24 hours postoperatively. The test group subsequently required twice the amount of analgesics during the 2nd through 5th days after operation compared to controls. All 5 patients who received intrathecal morphine developed urinary retention for 24 to 36 hours. The brief duration of analgesia, the increased narcotic use after the effects of the morphine dissipated, and urinary retention after a single intraoperative dose of intrathecal morphine suggest caution in using this technique.

Mixing studies during intracarotid artery infusions in an in vitro model.

Sporadic instances of retinal damage and of focal brain toxicity have been observed following intracarotid artery infusions of chemotherapeutic agents (such as BCNU and cis-platinum) for the treatment of glioblastomas. The episodic nature of these toxicities is consistent with the possibility that the drug solutions were streaming from the catheter tip and, therefore, were not well mixed or not uniformly distributed in all branches distal to the catheter tip location. To test this hypothesis, an in vitro system was fabricated which included a transparent model of the human carotid artery and its major branches. These were furnished with pulsatile flow of a blood simulant. Dye solutions infused at several infusion rates through various types of catheters in both supraophthalmic and infraophthalmic positions were monitored and recorded on videotape and photographic film. The effluent streams from distal branches of the model were collected, and the relative concentrations of dye in each branch were determined spectrophotometrically. The results indicate that infusate streaming occurs at low infusion rates. In some cases, the concentration in a given branch can be at least five times the expected concentration. Similar occurrences of streaming in vivo could cause focal toxicity. Methods to improve mixing should be used during intra-arterial administration of drugs; these include increasing the infusion rates and improving catheter tip design.

Drug streaming during intra-arterial chemotherapy.

Treatment of brain tumors by intra-arterial (IA) chemotherapy is occasionally complicated by sites of focal toxicity in the brain and retina. A possible cause of focal toxicity is non-uniform drug delivery due to intravascular drug streaming. To investigate this phenomenon in vivo, the authors examined the distribution of drug delivery after internal carotid artery (ICA) infusion in rhesus monkeys. Carbon-14 (14C)-labeled iodoantipyrine was delivered into the ICA of eight monkeys at slow infusion rates (1% to 2% of ICA flow) or at fast infusion rates (20% of ICA flow) combined with additional techniques to promote mixing with ICA blood. Two monkeys received intravenous (IV) 14C-antipyrine. Uniformity of delivery was assessed by comparing high-to-low ratios of isotope concentration in four brain regions evaluated by quantitative autoradiography. There was striking non-uniformity of drug delivery in the slow IA infusion group, with as much as 13-fold differences in drug concentration in anatomically contiguous areas. The values of high-to-low concentration ratios (mean +/- standard deviation) in individual autoradiographic planes were: 1) frontoparietal cortex: slow IA infusion 4.54 +/- 2.07, fast IA infusion 1.71 +/- 0.31, IV infusion 1.30 +/- 0.174; 2) frontoparietal white matter: slow IA infusion 2.94 +/- 1.45, fast IA infusion 1.59 +/- 0.41, IV infusion 1.34 +/- 0.21; 3) temporal cortex: slow IA infusion 5.43 +/- 3.57, fast IA infusion 1.69 +/- 0.24, IV infusion 1.67 +/- 0.25; 4) basal ganglia: slow IA infusion 3.6 +/- 2.9, fast IA infusion 1.18 +/- 0.10, IV infusion 1.09 +/- 0.04. Differences between concentration ratios after slow IA and fast IA infusion are significant (p less than 0.01); those between fast IA and IV infusion are not significant. Intra-arterial drug administration at infusion rates analogous to those currently used clinically results in drug streaming with markedly heterogeneous drug deposition in the perfused hemisphere. This may cause suboptimal drug levels in the tumor, and toxic levels at sites within the perfused hemisphere. This effect can be abrogated by techniques that eliminate drug streaming.