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Naoto Takeda

Publications and source records attributed to Naoto Takeda.

8 recordsLinked to original sources
PubMed2003

Phrenic nerve stimulation for diaphragm pacing with a spinal cord stimulator: technical note.

BACKGROUND: Diaphragm pacing with electrical stimulation of the phrenic nerve is an established treatment for central hypoventilation syndrome. The device, however, is not readily available, at least in Japan. We used the spinal cord stimulator for pain control for phrenic nerve stimulation. The purpose of this study is to evaluate the efficacy and feasibility of phrenic pacing with the compromise method. METHODS: We implanted a stimulator for spinal cord stimulation (Itrel 3 or X-trel, Medtronic, MN) in 4 patients with chronic hypoventilation because of brainstem dysfunction of various origins. The stimulation electrode was placed along the right phrenic nerve in the neck, and the device was implanted in the anterior chest. We used the cyclic mode, and set the parameters at 1 second ramp up, 2 seconds on, 3 seconds off. The pulse width and the frequency were set at 150 microsec and 21 Hz, respectively. The amplitude of the output was adjusted to obtain sufficient tidal volume and to maintain PaCO(2) at around 40 mm Hg. RESULTS: During the follow-up period from 6 to 19 months (mean 8.3 months), stable and sufficient ventilation were observed in all patients without complications. One patient with sleep apnea syndrome used the device only at night and became free from a respirator. Three patients who were completely respirator-dependent became ambulatory during the daytime. CONCLUSION: Though longer follow-up is necessary, diaphragm pacing by stimulation of the phrenic nerve with the spinal cord stimulator is feasible for a treatment of central hypoventilation syndrome.

Brain Stem↗
PubMed2003

[Diaphragm pacing with a spinal cord stimulator].

BACKGROUND: Diaphragm pacing with electrical stimulation of the phrenic nerve is an established treatment for central hypoventilation syndrome. The device, however, is not readily available in Japan. For pain control, we applied the spinal cord stimulator to bring about phrenic nerve stimulation. The purpose of this study is to evaluate the efficacy and feasibility of phrenic pacing using the compromise method. METHOD AND PATIENTS: We implanted a spinal cord stimulator in five patients with chronic central hypoventilation. The stimulation electrode was placed along the phrenic nerve in the neck, and the device was implanted in the anterior chest. We used the cyclic mode, and set the parameters at 1 second ramp up, 2 second on, 3 second off. The pulse width and the frequency were set at 150 mu sec and 21 Hz respectively. The amplitude was adjusted to obtain sufficient tidal volume and to maintain PaCO2 at around 40 mmHg. RESULT: During the follow-up period from 3 to 34 months (mean 23), stable and sufficient ventilation was observed in all patients without complications. CONCLUSION: Though longer follow-up is necessary, diaphragm pacing with the spinal cord stimulator is feasible as a treatment for central hypoventilation syndrome.

Adult↗
PubMed2002

Extreme night bradycardia developing after malfunction of a lumboperitoneal shunt.

CASE REPORT: An 8-year-old boy who was treated for hydrocephalus with lumboperitoneal shunting presented with extreme night bradycardia. RESULTS AND CONCLUSION: The night bradycardia disappeared after shunt revision, suggesting that the probable cause was secondary to long-lasting increased intracranial pressure (ICP). Long-lasting increased ICP is known to be associated with papilledema, but it has rarely been reported to induce night bradycardia in clinical practice. Extreme night bradycardia in this setting is not only a clinical sign of increased ICP but also a possible cause of cardiogenic sudden death, which must be borne in mind in the management of patients with shunted hydrocephalus.

Bradycardia↗
PubMed2002

Schwannoma arising from the tentorium at an unusual location: case report.

OBJECTIVE AND IMPORTANCE: We present a case of schwannoma attached to the tentorium. CLINICAL PRESENTATION: A 41-year-old woman without evidence of neurofibromatosis presented with a 3-month history of headache, positional vertigo, and truncal ataxia. Magnetic resonance imaging revealed an extra-axial cystic mass lesion in the left anteromedial cerebellar region with a dural tail sign. INTERVENTION: The tumor was removed completely by retrosigmoid craniotomy. Dense adhesion of the tumor to the inferior surface of the tentorium was confirmed during surgery. On light microscopic study, this neoplasm was composed of spindle cells and showed palisaded structures. Immunohistochemically, the tumor cells stained positive for S-100 protein and vimentin. Reticulin staining revealed a pericellular pattern of distribution of reticulin fibers. Electron microscopy confirmed the presence of a basement membrane encompassing the tumor cells. From these findings, the tumor was diagnosed as a schwannoma arising from the tentorium. CONCLUSION: To our knowledge, this case report is the first to describe a schwannoma arising from the tentorium. Our case report indicates that schwannoma is a possible pathology in the differential diagnosis of dura-based tumors.

Adult↗
PubMed2002

[Two cases of infectious mononucleosis-like syndrome associated with human herpes-virus 6].

We experienced two cases of infectious mononucleosis-like syndrome associated with human herpesvirus 6 (HHV-6). One of the patients had been under medication for depression and the other one for schizophrenia. Both of them were taking carbamazepine for more than a week along with the other drugs. The manifestation of the symptoms of those two were almost same, such as high fever, generalized eruption, liver dysfunction, lymph-adenopathy, and existence of atypical lymphocytes. Serological tests for EB virus, cytomegalovirus and herpes simplex virus showed no significant change while the tests for HHV-6 showed increased titers of IgG antibody during the courses. We also examined HHV-6 DNA by real time quantitative PCR tests for HHV-6, and they appeared significantly high in the peripheral blood samples.

Adult↗