High altitude: an unusual cause of neurological deterioration in a patient with an arteriovenous malformation

High altitude associated with neurological deterioration is an unusual presentation for an arteriovenous malformation (AVM). A case report of a man with a left temporal occipital AVM who developed symptoms that were markedly intensified by exposure to high altitude is presented. The AVM was removed surgically, and all symptoms resolved. The pathogenesis of this unusual AVM symptom complex is discussed in this report.     

Children grow and horses race: is the adiposity rebound a critical period for later obesity?

Background  

The adiposity rebound is the second rise in body mass index that occurs between 3 and 7 years. An early age at adiposity rebound is known to be a risk factor for later obesity. The aim here is to clarify the connection between the age at rebound and the corresponding pattern of body mass index change, in centile terms, so as to better understand its ability to predict later fatness.     

Synovial excrescences and cysts of the spine: clinicopathological features and contributions to spinal stenosis

Synovial cysts occur throughout the body and are generally benign lesions with limited clinical consequences. Juxtafacet cysts of the spine, in contrast, often press on a nerve root as it exits in the foramen, causing radiculopathy. Synovial tissue that emanates from the facet joint but extends medially, is an additional important cause of spinal stenosis. Over the past 5 years, neurosurgeons at our institution have operated on a large number of patients with back pain, with removal of abnormal synovial tissues. Histological examination of these tissues distinguishes the different types of pathologic processes responsible for producing symptoms. Juxtafacet cysts may be either mucin-filled ganglion cysts devoid of cyst lining or true synovial cysts with watery content and lined by synovial cells. Ganglion cysts arise in degenerated ligament at the facet joint, and occasionally within synovial stroma. Synovial cysts arise within synovium and, unlike synovial cysts in the extremities, have a thick wall containing granulation tissue, numerous histiocytes and giant cells. This hyperplastic, irritated synovium of the spine, which we term "synovial excrescences", is voluminous and this reactive part overshadows the cystic portion of the lesion in most instances. Iron pigment deposition and inflammation are mild to absent, making synovial excrescences different from pigmented villonodular synovitis. Synovial excrescences of the spine are an important cause of spinal stenosis, predominantly in elderly patients. Surgical removal of excrescences protruding into the spinal canal provides prompt and durable relief of symptoms, usually without the need for extensive bony laminectomy or spinal fusion. Several patients in our study had both spinal ganglion cysts and synovial excrescences, suggesting common risk factors for both lesions.     

Heat-induced superaggregation of amphotericin B modifies its interaction with serum proteins and lipoproteins and stimulation of TNF-alpha

The purpose of the present study was to examine the influence of heat-induced superaggregation of Amphotericin B (AmB) in the Fungizone (FZ) formulation on its interaction with human serum components and relate this to reduced toxicity. Whole serum distribution studies showed that a significantly lower percentage of AmB from HFZ was recovered in the high-density lipoprotein (HDL), low-density lipoprotein (LDL), and triglyceride-rich lipoprotein (TRL) fractions and a greater percentage recovered in the lipoprotein-deficient plasma (LPDP), though the majority of both preparations were recovered in LPDP. Circular dichroism (CD) and difference absorption spectroscopy were used to determine the stability of FZ and heat-treated FZ (HFZ) in the presence of HDL, LDL, serum, and albumin. The CD studies indicate that the "core" aggregate of HFZ is more stable in the presence of HDL and LDL, whereas the FZ is less stable and more dynamic with the core aggregate dissociating to a greater extent in the presence of either purified lipoprotein. Absorption studies with whole serum and purified albumin suggest that FZ aggregates are far less stable in the presence of albumin than HFZ and that interaction with serum albumin is a dominant feature for both drug preparations. HFZ also has a different effect on the cytokine response in vitro. Studies using THP-1 human monocytes show that HFZ provokes a smaller release of tumor necrosis factor (TNF)-alpha than FZ. This cytokine may be associated with the unpleasant side effects of AmB. These findings suggest that heat-induced superaggregation of AmB alters its interaction with HDL, LDL, serum proteins, and monocytes, and these findings may be important in explaining the reduced toxicity of the superaggregated form of AmB.     

Pseudoaneurysm of a lateral internal carotid artery in the middle ear

We report a case where a 7-year-old girl suffered significant aural bleeding following myringotomy of the tympanic membrane. Investigations by computed tomography scan, carotid angiography, and magnetic resonance angiography showed a lateral aberrant internal carotid artery (LACI) with a little pseudoaneurysm in the middle ear. The anomaly of the internal carotid artery was supposed to be congenital, and the pseudoaneurysm was supposed to be traumatic, formed after incision into the wall of the artery. Considerations about diagnosis, symptoms, and treatment are discussed. The patient was treated by balloon embolization in the internal carotid artery without sequelae.     

Phase I clinical trial of intracarotid bis-chloroethylnitrosourea (BCNU) and 2' dioxy-5-fluorouridine (FUDR) in malignant astrocytomas

Summary Systemic chemotherapy has been of limited benefit in the treatment of intracranial neoplasms, due, in part, to the inability to deliver effective drug doses to the neoplasm without systemic toxicity. We have completed a clinical trial of intracarotid BCNU and FUDR using an implantable pump in patients with unilateral malignant astrocytomas (Grade III and IV) in the hope of obtaining better tumor control with less systemic toxicity. Six patients had in-dwelling catheters placed in the internal carotid artery attached to a percutaneous refillable pump (Infusaid 400). The treatment program consisted of bolus BCNU 400 mg every 6 weeks and FUDR by continuous infusion at dosages ranging from 0.5 mg/24 h to 2.5 mg/24 h. The maximum tolerable dose of FUDR was 1 mg/24 h with ipsilateral mucositis and conjunctivitis being dose limiting factors. Flow studies demonstrated significant perfusion of the ipsilateral eye and surrounding face secondary to ophthalmic artery collaterals. No patient had systemic toxicity and the lowest WBC encountered was 2 400 with normal differential and platelets.