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Biomedical subjects

K Houkin

Publications and source records attributed to K Houkin.

At least 37 records · Page 2Linked to original sources
PubMed2000

Linkage of familial moyamoya disease (spontaneous occlusion of the circle of Willis) to chromosome 17q25.

BACKGROUND AND PURPOSE: Moyamoya disease is a cerebrovascular disease of unknown cause that mainly affects Japanese children. The incidence of familial occurrence accounts for 9% of cases. The characteristic lesions of moyamoya disease are occasionally seen in neurofibromatosis type 1, of which the causative gene (NF1) has been assigned to chromosome 17q11.2. METHODS: To determine whether a gene related to moyamoya disease is located on chromosome 17, we conducted microsatellite linkage analyses on 24 families containing 56 patients with moyamoya disease. Leukocyte DNA extracted from the family members was subjected to polymerase chain reaction for a total of 22 microsatellite markers on chromosome 17. The amplified polymerase chain reaction fragments were analyzed with GeneScan on an automated sequencer. RESULTS: Two-point linkage analysis gave a maximum log(10) odds (LOD) score of 3.11 at the recombination fraction of 0.00 for the marker at locus D17S939. The affected pedigree member method also showed a significantly low P value (<1. 0x10(-5)) for the 5 adjacent markers at 17q25. Multipoint linkage analysis also indicated that the disease gene is contained within the 9-cM region of D17S785 to D17S836, with a maximum LOD score of 4. 58. CONCLUSIONS: A gene for familial moyamoya disease is located on chromosome 17q25.

Cerebral Angiography↗
PubMed2000

Frontal lobe infarction due to hemodynamic change after surgical revascularization in moyamoya disease--two case reports.

A 60-year-old female and a 40-year-old male underwent surgical revascularization for moyamoya disease and suffered small infarction in the ipsilateral frontal lobe 3 or 4 days postoperatively. Neuroimaging suggested that the bypass flow had caused rapid progression of occlusive changes in the carotid forks, a diminishing of moyamoya vessels, and flow reduction in the anterior cerebral artery ipsilateral to surgery, leading to critical ischemia in the frontal lobe. Surgical revascularization improves the outcome of patients with moyamoya disease, but postoperative management such as hydration is important to avoid ischemic complications due to frontal lobe infarction.

Adult↗
PubMed2000

Digital recording in microsurgery. Technical note.

The authors examine the quality of intraoperative photography in which digital recording technology, including a microdigital camera and digital video paired with an operating microscope, is used during neurosurgery. A microdigital camera developed for this purpose (1.4 million pixels) was attached to an operating microscope and used during surgery. The same surgical views with precisely the same optical conditions were taken through the microscope by using both a conventional 35-mm camera and the microdigital camera, and the quality of the final output was compared. In addition, the quality of the digital camera photographs was compared with the still photograph clipped from the digital video recording. The quality of the photographs taken with a microdigital camera was superior to the quality of those obtained with the conventional 35-mm camera. The success rate of recording (what you see is what you get) was almost 100%. The quality of the still photographs clipped from the digital video was nearly equal to those taken with the digital camera. The microdigital camera system is superior to the conventional 35-mm camera in neurosurgery in terms of its success rate and the quality of the photography. It is also a space-saving system for storing the huge amount of data generated in the recording of surgical procedures, and the cost/performance ratio is superior to that of the conventional method. Digital technology including digital cameras and videos is very useful for clear recording of microsurgical procedures.

Humans↗
PubMed2000

[Clinical application of portable near infrared oximetry (HEO-200) to neurosurgical monitoring].

Near infrared spectroscopy (NIRS) have been accepted as a useful modality for non-invasive monitoring of brain oxygenation state. Using a newly developed NIRS apparatus, HEO-200, the authors continuously monitored the changes in the oxygenation state of brain hemoglobin during carotid endarterectomy (CEA) or carotid balloon occlusion tests (BOT) in 21 patients. Somatosensory evoked potentials (SEP), regional cerebral blood flow (rCBF) or transcranial Doppler sonography (TCD) were also employed to compare with the NIRS-responses. In 7 of 21 patients, the carotid artery occlusion caused a continuous deoxygenation of brain hemoglobin as well as a decrease in total hemoglobin. These findings correlated well with temporary neurological deficits and a marked reduction of rCBF in the ipsilateral hemisphere in patients who underwent carotid BOT under local anesthesia. The patients also showed a marked decrease in the N20 amplitude of SEP during CEA under general anesthesia. Restoration of blood flow immediately resolved these findings. The other 14 patients demonstrated no or only transient changes on NIRS as well as on SEP and rCBF study. HEO-200 could non-invasively monitor the relative changes of cerebral oxygenation state with good time resolution, and detect critical ischemia during CEA and carotid BOT.

Aged↗
PubMed1999

Intra-operative premature rupture of the cerebral aneurysms. Analysis of the causes and management.

The causes and management of intra-operative premature rupture are analysed and discussed. During the past 6 years, the authors, performed 398 consecutive direct surgical interventions for ruptured cerebral aneurysms. Intra-operative premature rupture is defined as a rupture which occurs before the securing of the parent arteries or the neck of the aneurysm and is out of control, at least temporarily. The causes and management were retrospectively analyzed by reviewing video tape recordings. Intra-operative premature ruptures which met the above definition occurred in 24 cases (6.0%). The causes were as follows: 1.) dural opening and arachnoid opening (8.3%), 2.) haematoma removal (12.5%), 3.) brain retraction (16.7%), 4.) aneurysm dissection (62.5%). A double suction technique was used to control bleeding and haemostasis with a small piece of cotton or a temporary clip, performed in 20 cases (83.3%). However, in cases with premature rupture immediately after the dural or arachnoid opening, the extension of the haematoma into the subarachnoid space resulted in severe brain swelling and partial resection of the brain had to be done to secure temporary clipping. The double suction technique and primary haemostasis using a small piece of cotton or temporary clip resulted in good outcome even in cases with premature rupture. However, very early premature rupture also occurred although its incidence was extremely rare. The removal of part of the brain can secure the working space but the outcome was poor.

Adult↗
PubMed1999

Arachnoid membrane closure. Prevention of postoperative cerebrospinal fluid leakage.

BACKGROUND: Opening the arachnoid membrane causes leakage of the cerebrospinal fluid (CSF). CSF spillage and collection in the subdural, epidural, and/or subcutaneous space are occasionally seen on a postoperative CT scan. Closure of the arachnoid membrane is considered to be unnecessary because most of the fluid in the extracerebral space is temporary and disappears spontaneously. However, in some cases, this CSF collection results in serious complications such as brain compression, extracerebral hematoma, intractable meningitis, and skin problems. In this study for prevention of CSF leakage, the arachnoid membrane was tightly closed with 10-0 nylon after a small opening was made for cerebrovascular bypass surgery. METHODS: The arachnoid membrane closure was performed in 18 patients (20 sides) after bypass surgery between 1994 and 1995. As a control, 51 patients (57 sides) had conventional bypass surgery without the arachnoid membrane closure. RESULTS: The radiological findings revealed that only one (5%) of the patients had a small fluid collection after arachnoid membrane closure, which was significantly lower than the control (49%). CONCLUSION: Arachnoid membrane closure is a simple technique and is effective for prevention of postoperative extracerebral CSF collection.

Arachnoid↗
PubMed1999

Analysis of optical signals evoked by peripheral nerve stimulation in rat somatosensory cortex: dynamic changes in hemoglobin concentration and oxygenation.

The origins of reflected light changes associated with neuronal activity (optical signals) were investigated in rat somatosensory cortex with optical imaging, microspectrophotometry, and laser-Doppler flowmetry, and dynamic changes in local hemoglobin concentration and oxygenation were focused on. Functional activation was carried out by 2-second, 5-Hz electrical stimulation of the hind limb under chloralose anesthesia. These measurements were performed at the contralateral parietal cortex through a thinned skull. Regional cortical blood flow (rCBF) started to rise 1.5 seconds after the stimulus onset, peaked at 3.5 seconds (26.7% +/- 9.7% increase over baseline), and returned to near baseline by 10 seconds. Optical signal responses at 577, 586, and 805 nm showed a monophasic increase in absorbance coincident with the increase in rCBF; however, the signal responses at 605 and 760 nm were biphasic (an early increase and late decrease in absorbance) and microanatomically heterogeneous. The spectral changes of absorbance indicated that the concentrations of both total hemoglobin and oxyhemoglobin increased together with rCBF; deoxyhemoglobin, increased slightly but distinctly (P = 0.016 at 1.0 seconds, P = 0.00038 at 1.5 seconds) just before rCBF increases, then decreased. The authors conclude that activity-related optical signals are greatly associated with a moment-to-moment adjustment of rCBF and metabolism to neuronal activity.

Animals↗
PubMed1999

Transverse cervical artery bypass pedicle for treatment of common carotid artery occlusion: new adjunct for revascularization of the internal carotid artery domain.

OBJECTIVE: We present two cases of common carotid artery occlusion that were treated by vascular reconstruction using the transverse cervical artery. METHODS: Two patients with common carotid artery occlusion presented with transient ischemic attacks resulting from decreased cerebral blood flow on the affected side. Both patients underwent vascular reconstruction using the transverse cervical artery. The transverse cervical artery was anastomosed to the ipsilateral external carotid artery at its origin, as a pedicle graft. A superficial temporal artery-middle cerebral artery anastomosis was then performed. RESULTS: The postoperative courses were uneventful. The transverse cervical artery bypass grafts were patent, and cerebral blood flow increased to normal levels. CONCLUSION: Transverse cervical artery grafting provides a less tedious alternative to saphenous vein interposition grafting for revascularization of the internal carotid artery domain.

Aged↗
PubMed1999

Aggravation of brainstem symptoms caused by a large superior cerebellar artery aneurysm after embolization by Guglielmi detachable coils--case report.

An 81-year-old male presented with right oculomotor nerve paresis and left hemiparesis caused by a mass effect of a large superior cerebellar artery aneurysm. Endovascular treatment was performed using Guglielmi detachable coils. The patient subsequently suffered aggravation of the mass effect 3 weeks after the embolization. Bilateral vertebral artery occlusion was performed, which decreased the cerebral edema surrounding the aneurysm, but his neurological symptoms did not improve. Parent artery occlusion is recommended as the first choice of treatment for an unclippable large or giant aneurysm causing a mass effect on the brainstem.

Aged↗
PubMed1999

Telemedicine in neurosurgery using international digital telephone services between Japan and Malaysia--technical note.

A new image transmission and teleconference system using international digital telephone services was established between Japan and Malaysia. This new system consists of an ordinary personal computer, image scanner, and terminal adapter for digital telephone lines. The quality of images transferred using this system was high enough for diagnosis and discussion except for images such as radiographs requiring huge data transfer. Transmission of one image took approximately 20 seconds. The cost performance was almost equal to the conventional mailing system. The most remarkable advantage of this new system is the high quality of transferred images, the cost and time performance, and security of the medical information. New communication systems using international digital networks including the internet may allow re-distribution of medical resources between advanced countries and developing countries in neurosurgery.

Academic Medical Centers↗
PubMed1999

Long-term patency of radial artery graft bypass for reconstruction of the internal carotid artery. Technical note.

Reconstruction of the carotid artery by using a radial artery graft is a useful option that can produce reliable long-term patency for the surgical treatment of giant and/or large aneurysms of the cavernous and paraclinoid internal carotid artery (ICA). During the past 10 years, 43 patients with intracavernous and paraclinoid giant aneurysms of the ICA have been treated by reconstruction of the ICA with radial artery grafts after ligation of the cervical ICA. The long-term patency of the grafted radial artery was evaluated over more than a 5-year period (mean 7.2 years) in 20 of these patients by using magnetic resonance angiography or conventional angiography. There was no late occlusion of the graft in any of these cases. Stenotic graft changes were observed in two cases.

Adult↗
PubMed1999

[Digital recording in neurosurgery].

The purpose of this study is to examine the image quality of multi-media for digital recording of surgical procedure using an operating microscope in neurosurgery. For video recording, high vision recording, digital video recording and analogue VHS recording were used. For still pictures, an analogue camera with 35 mm silver halide film and a micro-digital camera were used. The quality of photographs taken with a microdigital camera was superior to the quality of those taken with the conventional 35 mm film camera. The micro-digital camera system is superior to the conventional 35 mm camera in neurosurgery in its quality and success rate. In video recording, high vision analogue recording was superior to any other media as far as its image quality is concerned although its practical convenience is limited and cost performance is not always good. On the other hand, digital video can record high quality images, including still pictures, with satisfactory quality to the neurosurgeon. These digital recording media are also space saving for storing the huge amount of data obtained during surgery and the cost-performance is superior to that of the conventional method. In the near future, most of surgical procedures are supposed to be expected using digital media.

Humans↗
PubMed1998

Role of basic fibroblast growth factor in the pathogenesis of moyamoya disease.

The pathogenesis of moyamoya disease is still under investigation. In this study, the authors focus on the role of cytokines in the pathogenesis of moyamoya disease by using immunohistochemical analyses. The authors examined two specimens in the circle of Willis obtained at autopsy from two patients with moyamoya disease and two additional specimens obtained from control cadavers with atherosclerotic stenosis of the intracranial carotid arteries. Immunohistochemical examinations of the sections of the major intracranial arteries were performed using antismooth muscle cells (SMCs), monocytes, growth factor, cell nuclear antigen, and fragmented DNA antibodies. Basic fibroblast growth factor (bFGF) staining was present only in the endothelial cells of the moyamoya disease specimens and was not seen in control samples. In addition, the endothelial cells and SMCs in the media were positive for terminal deoxynucleotidyl transferase-mediated biotinylated deoxyuridine triphosphate nick-end labeling of fragmented DNA method but not in the SMCs in the intima in moyamoya disease specimens, which indicates that an apoptotic process is active in only SMCs in the media but not in the intima. In conclusion, it is suggseted that the presence of bFGF in the media specifically seen in moyamoya disease suppresses the apoptotic process of SMCs in the intima.

Journal Article↗
PubMed1998

Regional cerebral blood flow in pediatric moyamoya disease: age-dependent decline in specific regions.

Thirteen pediatric patients (ages 4-13 years) who underwent surgical treatment were examined regarding their rCBF in the preoperative periods. The postoperative rCBF was measured 39 times in these 13 patients. Thirteen healthy normal subjects (ages from 6 to 21 years) were also examined. The rCBF in the operculum and in the frontal, parietal, and occipital lobes was measured with 133Xe inhalation method and single photon emission computed tomography. In the parietal and occipital lobes, the preoperative rCBF had a negative and significant correlation with their ages, but not in the operculum or frontal lobe. However, subsequent to the surgical treatment, the rCBF increased significantly in the patients 5 years old or less, and then post-operative rCBF values had significant negative correlations with age in each region.

Adolescent↗
PubMed1998

Postoperative hyperperfusion in dural arteriovenous fistula associated with venous ischemia: case report.

BACKGROUND: It is well known that carotid endarterectomy and extracranial-intracranial arterial bypass sometimes cause postoperative hyperperfusion, and vasoparalysis attributable to long-standing ischemia has been suggested as the cause. It is also well known that dural arteriovenous fistula (AVF) sometimes causes cerebral ischemia attributable to venous hypertension. However, there are few reports regarding the postoperative changes of regional cerebral blood flow (rCBF). METHODS: We report a case of dural AVF of the left transverse/sigmoid sinuses, occurring in a 64-year-old man. Intraoperative transvenous embolization combined with transarterial embolization was performed, and the rCBF was measured pre- and postoperatively using 99mTc-hexamethyl-propylene amine oxime and single-photon emission computed tomography (SPECT). RESULTS: Preoperative SPECT disclosed a marked rCBF reduction in the left temporal, parietal, and occipital lobes. Complete obliteration of the AVF was attained after the intraoperative transvenous embolization, without any neurological deterioration. However, postoperative SPECT demonstrated temporary hyperperfusion in these regions. CONCLUSIONS: Sudden resolution of venous ischemia can lead to postoperative hyperperfusion, and pre- and post-treatment rCBF studies are important to prevent complications related to hyperperfusion.

Arteriovenous Fistula↗
PubMed1998

Intracranial aneurysms associated with aortitis syndrome: case report and review of the literature.

OBJECTIVE AND IMPORTANCE: Aortitis syndrome is a systemic vasculitis of unknown etiology, affecting mainly the major branches of the aorta and leading to stenosis or occlusion. Intracranial aneurysms are rarely associated with this syndrome. Only 15 cases have been previously reported. CLINICAL PRESENTATION: A 54-year-old woman with a 10-year history of aortitis syndrome demonstrated nonruptured cerebral aneurysms in the left internal carotid and anterior communicating arteries, with decreased flow in the right internal carotid artery and ipsilateral A1 segment. INTERVENTION: The patient underwent clipping of the aneurysms through a left pterional craniotomy and transsylvian approach. CONCLUSION: In our review of 16 reported cases, including the present case (13 with ruptured aneurysms and 3 with nonruptured aneurysms), there were 25 saccular aneurysms, and we noted the following clinical characteristics: 1) patient age was 26 to 64 years, with an average of 50.2 years; 2) aneurysms arose predominantly along the course of collateral flow, especially in the vertebrobasilar system (13 of 25 aneurysms, 52.0%); 3) there was a high incidence of multiplicity (7 of 16 cases, 43.8%). These characteristics suggest that increased hemodynamic stress, produced by stenosis or occlusion of the major branches of the aorta and systemic hypertension, plays an important role in the development of cerebral aneurysms in patients with this syndrome.

Aortitis↗