Histological findings at the boundary of craniopharyngiomas

Although a craniopharyngioma is grossly well circumscribed, microscopically the borders are frequently irregular and may be associated with gliosis in the adjacent brain tissue. In the current study, we investigated the histology of the interface between craniopharyngiomas and surrounding normal structures such as the hypothalamus and pituitary gland. Histologically, we classified the findings at the boundary of craniopharyngiomas into three types. In type 1, a relatively thick capsule-like tissue was identified at the boundary between the craniopharyngioma and surrounding normal structure composed of tumor cells and inflammatory changes. In type 2, a craniopharyngioma had a relatively clear cleavage between the surrounding gliosis. In type 3, the boundary had some interdigitation of the tumor in the surrounding gliotic layer adjacent to the craniopharyngioma. In types 1 and 3, surgeons may fail to accomplish complete resection of the tumor. These histological features may result in recurrence of craniopharyngioma even after gross total resection.     

Functional aortic stenosis diagnosed in fetal period

We report a case of fetal congenital heart disease prenatally diagnosed as critical aortic valve stenosis at 25 weeks of gestation. Fetal echocardiography demonstrated severe mitral regurgitation, aortic valve stenosis, hypocontractility of the left ventricle, and showed retrograde flow in the aortic arch like HLHS (hypoplastic left heart syndrome). However, soon after delivery, improvement in the baby's hemodynamics and myocardial contractility were recognized without any treatment.     

Rupture of a thoracic aortic aneurysm: a rare adverse reaction following systemic tissue plasminogen activator infusion

We present a patient with rupture of a thoracic aortic aneurysm occurring after systemic infusion of tissue plasminogen activator for the treatment of acute ischemic stroke, which was successfully treated with the placement of an endovascular stent-graft.     

Antihyperalgesic and side effects of intrathecal clonidine and tizanidine in a rat model of neuropathic pain

BACKGROUND: Although intrathecal clonidine produces pronounced analgesia, antinociceptive doses of intrathecal clonidine produce several side effects, including hypotension, bradycardia, and sedation. Intrathecal tizanidine, another alpha(2)-adrenergic agonist, has provided antinociception without producing pronounced hemodynamic changes in animal studies. However, it has been unclear whether antihyperalgesic doses of intrathecal clonidine and tizanidine produce hypotension and bradycardia in a neuropathic pain state. This study was designed to evaluate the antihyperalgesic effects and side effects of intrathecal clonidine and tizanidine in a rat model of neuropathic pain. METHODS: Male Sprague-Dawley rats were chronically implanted with lumbar intrathecal catheters, and the sciatic nerve was loosely ligated. After 21-28 days after surgery, the rats received intrathecal clonidine (0.3, 1.0, and 3.0 microg) and tizanidine (1.0, 2.0, and 5.0 microg), and the antihyperalgesic effects of thermal and mechanical stimuli were examined. In addition, the changes in blood pressure and heart rate, sedation level, and other side effects after intrathecal administration of drugs were recorded. RESULTS: The administration of 3.0 microg intrathecal clonidine or 5.0 microg tizanidine significantly reversed both thermal and mechanical hyperalgesia. The administration of 3.0 microg intrathecal clonidine, but not 5.0 microg tizanidine, significantly decreased mean blood pressure and heart rate and produced urinary voiding. A greater sedative effect was produced by 3.0 microg intrathecal clonidine than by 5.0 microg tizanidine. CONCLUSION: The antihyperalgesic dose of intrathecal clonidine and the antinociceptive doses produced several side effects. Intrathecal tizanidine at the dose that reversed hyperalgesia would be preferable for neuropathic pain management because of absence of hypotension and bradycardia and lower incidence of sedation.     

A case of membranous nephropathy with ANCA-associated necrotizing glomerulonephritis during oral administration of PTU for Graves' disease

We experienced a coincidental case of two types of glomerulopathy associated with Graves' disease. A 64-year-old man, who had been treated with propylthiouracil(PTU) for Graves' disease for 15 years, was admitted to our hospital for macroscopic hematuria and rapidly progressive deterioration of renal function. Although his thyroid function had been within the normal range during treatment, the level of thyrotropin receptor antibody(TRAb) gradually increased from a year before admission. Serological tests revealed that he was positive for myeloperoxidase-antineutrophil cytoplasmic antibody(MPO-ANCA). The renal biopsy specimen showed necrotizing and crescentic glomerulonephritis(GN) superimposed on membranous nephropathy(MN). This is a rare case of MN complicated with ANCA associated crescentic GN in a Graves' disease patient. Association of these two renal alterations was not clearly defined. MN involved with Graves' disease also has been rarely reported. Some reports demonstrated deposition of thyroglobulin and other thyroid related antigens in the glomeruli. In the present case, long-term impairment of Graves' disease and elevation of TRAb might have been responsible for the formation and deposition of thyroid-associated immune complex in the glomeruli. As for crescentic GN, PTU might have induced ANCA-associated GN independently of MN. This case is instructive for considering the relation between Graves' disease and renal injury.     

New possibilities for stereotaxis. Information-guided stereotaxis

Information-guided stereotaxis, assisted by visualization of medical information, will become the next generation of neurosurgical systems. We performed 76 open MRI surgeries at Tokyo Women's Medical University between March 3, 2000 and April 12, 2001. Of them, comparisons of pre- and post-operative MR images for malignant gliomas in 21 cases revealed an average resection rate of 90.3% (the maximum 100%, the minimum 55%). In this article we describe real time updated navigation, augmented reality navigation, three-dimensional navigation, chemical navigation, information-guided navigation system (High definition visual Computer Aided Surgery System: HivisCAS), and open MRI-guided surgery that we are developing.