RESUMEN
Artificial intelligence (AI) is often considered a black box because it provides optimal answers without clear insight into its decision-making process. To address this black box problem, explainable artificial intelligence (XAI) has emerged, which provides an explanation and interpretation of its decisions, thereby promoting the trustworthiness of AI systems. Here, a memristive XAI hardware framework is presented. This framework incorporates three distinct types of memristors (Mott memristor, valence change memristor, and charge trap memristor), each responsible for performing three essential functions (perturbation, analog multiplication, and integration) required for the XAI hardware implementation. Three memristor arrays with high robustness are fabricated and the image recognition of 3 × 3 testing patterns and their explanation map generation are experimentally demonstrated. Then, a software-based extended system based on the characteristics of this hardware is built, simulating a large-scale image recognition task. The proposed system can perform the XAI operations with only 4.32% of the energy compared to conventional digital systems, enlightening its strong potential for the XAI accelerator.
RESUMEN
PURPOSE: In this study, we investigated the magnetic resonance (MR) imaging characteristics of rapidly destructive coxarthrosis (RDC) caused by osteonecrosis of the femoral head. MATERIAL AND METHOD: We reviewed 11 hip MR images (10 patients) of osteonecrosis of the femoral head with RDC. MR findings of 11 RDC were compared with those of Ficat stage IV osteonecrosis of the femoral head as a control. RESULTS: The MR findings of osteonecrosis, involving the entire femoral head, bone marrow edema in the acetabulum, intraarticular loose bodies on the inferomedial portion of the hip joint, and synovial proliferation were significant in RDC as compared with those of osteonecrosis of the femoral head only. CONCLUSION: Distinct findings of MR imaging in conjunction with plain radiographs could be used to facilitate diagnosis, treatment, and prognosis in RDC.
Asunto(s)
Acetábulo , Médula Ósea , Diagnóstico , Edema , Cabeza , Cadera , Articulación de la Cadera , Imagen por Resonancia Magnética , Osteoartritis de la Cadera , Osteonecrosis , PronósticoRESUMEN
BACKGROUND: Intracranial complications of paranasal sinus infection are rare and may be misdiagnosed during an initial evaluation because they often show subtle symptoms, which include elusive physical and neurological findings and imaging. The late recognition of these conditions and the delayed treatment can increase morbidity and mortality rates. We aimed to characterize the typical clinical features of intracranial complications associated with sinusitis. METHODS: Twelve patients who visited the Eulji Medical Center from 1994 to 2000, with sinogenic suppurative intracranial lesions were reviewed. Medical records and radiological studies were reviewed retrospectively. RESULTS: There were 12 cases with 15 sinogenic intracranial complications. The ratio of males to female was 2 : 1. The ages of patients ranged from 16 to 81 (average: 46.7). Four cases had meningitis, four had focal cerebritis, three had cavernous sinus throm-bophlebitis, two had subdural empyema, and two had epidural abscess or empyema. The primary lesions of paranasal sinusitis were located at the sphenoid in three, ethmoid sinus in two, frontal sinus in one and the multiple sinus in six. The outcome revealed complete recovery in six cases, mild neurologic sequelae in three cases, death in two cases and recurrence in one case. CONCLUSIONS: The type of intracranial complication and origin of paranasal sinusitis may be changing. Cases in which such complications are suspected, in order for an early diagnosis, a MRI should be considered. The successful management of intracranial complications consists of timely antibiotics therapy combined with surgical drainage of the loculated infection. (J Korean Neurol Assoc 19(5):457~463, 2001)
Asunto(s)
Femenino , Humanos , Masculino , Antibacterianos , Seno Cavernoso , Drenaje , Diagnóstico Precoz , Empiema , Empiema Subdural , Absceso Epidural , Senos Etmoidales , Seno Frontal , Imagen por Resonancia Magnética , Registros Médicos , Meningitis , Mortalidad , Recurrencia , Estudios Retrospectivos , SinusitisRESUMEN
PURPOSE: Recently, peripheral nerve allograft was considered to be able to provide valuable nerve materials for large nerve defect. However, the rejection response and slow regeneration of graft have continued to be serious deterrent to application of nerve allograft. Although many studies for reducing graft immunogenicity have been reported, the method to promote nerve regeneration has not been reported. The purpose of this study is to investigate the promoting effects of the basic fibroblast growth factor (bFGF) on the regeneration of allografted nerve. MATERIALS AND METHODS: Ninety-five female Wistar white rats and 90 allogenic Brown-Norway black rats were the recipients and the donors of 1.5 cm sciatic nerve grafts mutually. Recipient rats were randomly allocated to cyclosporin A immunosuppressed group or control group. And each group was subdivided into non-bFGF subgroup, 10 pg-bFGF subgroup and 100 pg-bFGF subgroup. Regeneration of grafted nerves graft was assessed by histological and electomicroscopic studies at 4th, 8th and 12th weeks. RESULTS: Basic fibroblast growth factor showed its promoting effect on the regeneration of the allografted sciatic nerve at 4th week in CsA-treated group and 8th week in non-CsA group. CONCLUSION: Basic fibroblast growth factor promotes the regeneration of the allografted nerve in rat.
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Animales , Femenino , Humanos , Ratas , Aloinjertos , Ciclosporina , Factor 2 de Crecimiento de Fibroblastos , Regeneración Nerviosa , Nervios Periféricos , Regeneración , Nervio Ciático , Donantes de Tejidos , TrasplantesRESUMEN
We reviewed 46 hips of the 36 patients treated with free vascularized fibular graft for avascular necrosis of femoral head with a mean follow-up of 39.9 months (ranging from 2 years to 6 years 4 months). There were thirty-four men and two women. The mean age of patients at the time of operation was 36.6 years (ranging from seventeen to fifty-seven years). The procedure was performed on both hips in ten patients. Of the 46 hips, twenty-nine were idiopathic, ten alcoholic, six steroid induced, and one traumatic. According to Ficats stage, there were eighteen in Stage 2A, fifteen in Stage 2B and thirteen in Stage 3. According to Ohzonos classification, there were four in Type 1B, forty in Type 1C and one in Type 3B. Clinical assessments according to the cause and severity of the disease were evaluated using Harris hip scoring system. Thirty-two hips(69.6%) were excellent, 9 hips(19.6%) were good, 2 hips(4.3%) were fair, and 3 hips(6.5%) were poor. Therefore clinically satisfactory results, including excellent and good, were obtained in 41 hips(89.2%). Radiographic assessments according to healing of avascular necrosis lesion and collapsing the femoral head postoperatively were performed. Thirty hips(65.2%) were excellent, 9 hips(19.6%) were good, 4 hips(8.7%) were fair, and 3 hips(6.5%) were poor. Therefore radiographic satisfactory results were obtained in 39 hips(84.8%). Clinical and radiographic assessments according to Ohzonos classification were also evaluated. Clinically satisfactory result were obtained in 6 hips(100%) of Type 1A and 3B in 33 hips(82.5%) of Type 1C. The etiological factors didn t affect the results. There were two cases of peroneal nerve palsy in which one was irreversible and one case of clawing of great toe as complications. In conclusion, free vascularized fibular graft appears to be a very effective method for Ficats stage 2A, 2B, and early stage 3 of symptomatic avascular necrosis of femoral head, in Ohzonos Type 1C which have a high incidence of collapse.
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Animales , Femenino , Humanos , Masculino , Alcohólicos , Clasificación , Estudios de Seguimiento , Cabeza , Cadera , Pezuñas y Garras , Incidencia , Necrosis , Parálisis , Nervio Peroneo , Dedos del Pie , TrasplantesRESUMEN
Plate fixation is being regarded as one of the reliahle fixation method in the management of tibial fractures. But this technique may leave many complications including infection. However, delayed local infection which developed several weeks after open reduction on the tibia has been rarely described as a complication in the literatures. The purpose of this study is to evaluate the contributing factors to the delayed locaI infection in tibial fracture treated with plate fixation. Authors reviewed and analyzed the 60 cases of tihial fracture that were treated with plate and screws from 1989 to 1996. Analyses dealt with fracture classification, laboratory and radiographic findings and the site of plate application. We defined a delayed local infection as a condition in which patient has infection signs on Jaboratory and physical examination at or over 8 week post-operation without any evidence of osteomyelitis on plain radiographs. We found 7 cases of delayed local infection out of 60 tibial fractures from 8 to 21 weeks postoperatively with an average of 14.1 weeks. All the 7 cases that had been treated with plate on medial aspect of tibia were treated by administration of antibiotics without surgery such as debridement or removal of hardwares. Authors concluded that the medial plating was the most important factor of the development of delayed local infection(Z=1.78).
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Humanos , Antibacterianos , Clasificación , Desbridamiento , Osteomielitis , Examen Físico , Tibia , Fracturas de la TibiaRESUMEN
Vascularized fibular graft is one of the treatment option for avascular necrosis of femoral head (ANFH) and has been known as providing a strut mechanical support and new vascular bed. It is very important to evaluate a healing process in femoral head after vascularization procedure. But a plain radiographic finding has a problem to assess pathological changes of ANFH treated with vascularized fibular graft. Authors analyzed chronogical changes of Tc-99m-HDP bone scan in 31 cases of ANFH treated with vascularized fibular graft from April, 1991 to May, 1994 and following results were obtained. l. Until 2 months after surgery, no change in size of cold defect area and no significant change in extent of RI uptake in reactive zone were noted. 2. During 2 months and 6 months after surgery, slight decrease in size of cold defect area and minimal changes in extent of RI uptake in reactive zone were observed. 3. During 6 months and 12 months after surgery, size of cold defect area decreased to 1/2 and changes in extent and degree of RI uptake in reactive zone were observed. 4. During 1 year and 2 years after surgery, size of cold defect area were minimal and sometimes faded away. RI uptake with decreased density in reactive zone broadened and moved to subchondral area. 5. After 2 years after surgery, cold area faded away and small increased RI uptake were observed in same site. In conclusion, Tc-99m-HDP bone scan which is economic and easily applicable in a patient is very useful for follow up study in ANFH treated with vascularized fibular graft.
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Humanos , Estudios de Seguimiento , Cabeza , Cadera , Necrosis , TrasplantesRESUMEN
In our series with old electrical burn around the the wrist, there are several characteristics: for example, bad scarring in palm and volar aspect of wrist and distal forearm, large multiple defects of the flexor tendons, low median and ulnar nerve palsy, and occasionally insufficient blood supply. Between 1992 and 1995, we treated 8 cases of 7 patients with staged reconstruction. 4 patients with bilateral involvements had below-elbow amputee of contralateral upper extremity. The common approachs in each were soft tissue coverage, staged tendon reconstructiuon, and opponensplasty. The length of time between the injury and tendon reconstruction was 9 months on an average. Soft tissue coverage consisted of: 1. free tissue transfer (n=3), 2. abdominal (n=3) or groin (n=2). Total numbers of flexor tendon reconstruction were 26. Among them, staged reconstruction using silicone prosthesis were done in 18 tendons and primary tendon graft following tenolysis were done in 8 tendons. The time between first and second stage tendon reconstruction was 4.13 months. In all cases, opponen-splasty using extensor indicis proprius (n=4), extensor pollicis longus (n=2), and extensor digiti mini- mi (n=l), were performed. Good functional improvement of the hand were obtained in all cases. Patient s satisfaction were much better than the degree of functional improvement of the hand.
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Humanos , Amputados , Quemaduras , Cicatriz , Antebrazo , Ingle , Mano , Prótesis e Implantes , Siliconas , Tendones , Trasplantes , Neuropatías Cubitales , Extremidad Superior , MuñecaRESUMEN
Operations on the inner aspect of the pelvis are often necessary for irreducible fracture of the ilium, irreducible fracture of superior and medial portion of the acetabulum, tumors and infections involving iliac fossa, and fracture-dislocation and infection of the sacro-iliac joint. Until now Letournel and Judet's ilioinguinal and iliofemoral approaches provided access to anterior column of the pelvis by elevating muscle layer on inner aspect of the pelvis. We used modified iliofemoral approach using ASIS(anterior superior iliac spine) osteotomy to gain better access to anterior column, the pelvlc brim, and in some occasions as far as anterior sacroiliac joint while avoiding injury to the structures in the inguinal ligament and lateral femoral cutaneous nerve and reported six cases treated with this approach. In conclusion, a modified iliofemoral approach using ASIS osteotomy is a useful approach which can obtain an excellent exposure in the inner pelvis.
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Acetábulo , Ilion , Articulaciones , Ligamentos , Osteotomía , Pelvis , Articulación SacroiliacaRESUMEN
Twenty-five patients with unstable fracture or fracture-dislocation of the thoracolumbar and lumbar spines were treated with Cotrel-Dubousset instrumentation. Internal fixation was done in two ways; long rodding in seventeen patients and short rodding in eight. Short segment posterolateral or posterior autogenous iliac bone graft was done in all cases. The amount of correction of the collapsed anterior vertebral body height and the local kyphotic angle at the immediate post-operation were similar between the two groups, but loss of correction at last follow-up was more severe in the short rodding group. Instrument failure was also more common in the short rodding group. In conclusion, it was found that short segment stabilization of spine fractures with Cotrel-Dubousset instrument can effectively reduce fracture but can not maintain reduction until fusion. Therefore, long rodding was reconfirmed to be the better method of stabilization of the thoracolumbar and lumbar spines fractures.
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Humanos , Estatura , Estudios de Seguimiento , Métodos , Columna Vertebral , TrasplantesRESUMEN
There are several considerations in performing free vascularized fibular graft for the treatment of the large bone defect, e.g., bone fixation, additional bone graft, and management of complication. Authors have analyzed 25 cases treated with free vascularized fibular graft at Holy Family Hospital between Jun. 1985 and Dec. 1994. The mean follow up was 27.4 months The results were as follows: 1. The causes of the defect were traumatic defect with infection of 16 cases, bone tumor of 4 cases, congenital pseudoarthrosis of tibia of 3 cases and osteomyelitis of 2 cases. 2. Hypertrophy of the graft was more common in the lower extremity and in the patient under the age of 15. 3. Nonunion of graft occurred in 4 cases(16%). These cases were fixed with screws and/or pin ini tially and subsequently treated with rigid internal fixation. 4. Stress fracture of graft occurred in 3 cases(12%). Two cases of them were treated with internal fixation. 5. Additional bone graft were performed in 6 cases(24%), among 17 cases who had bone defect of lower extremity in adult. In conclusion, authors emphasize that rigid internal fixation and additional bone graft in performing free vascularized fibular graft are recommended for obtaining early solid bony union and achieving early rehabilitation.
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Adulto , Humanos , Estudios de Seguimiento , Fracturas por Estrés , Hipertrofia , Extremidad Inferior , Osteomielitis , Seudoartrosis , Rehabilitación , Tibia , TrasplantesRESUMEN
Incidence of non-contiguous multiple spine fracture was increased from 3.2%~4.5% at 1960th and 70th to 5.7% ~23.8% at 80th and 90th. But there is no reports in Korea which has high incidence of traffic and industrial accidents. In 345 consecutive patients with acute spine fracture, we found that 43 patients (12.5%) had multiple non-contiguous spine fractures. At the 43 patients studies 37 (87.4%) sustained fractures at 2 levels while 6 had more than 3 levels of injury, 26 were injured by fall from heights, 27 (62.8%) had 2.33 associated injuries on an average, and 12 (27.9%) had a neurologic deficit. There are five patterns account for 26 (50%) of the total number of patients. In 19 patients (44.2%), there was a mean 29.3 days delay (from 3 to 233 days) in diagnosis of the minor lesions. In 19 delay diagnosed minor lesions, it confirmed by bone scan in 12 patinets(63.6%). Two patients died within 24 hours after accident, and 41 patients (41 major and 50 minor fractures) were treated in our hospital. Among them, 21 (51.2%) needed modification of treatment by the presence of non-con- tiguous multiple spine fractures. According to above findings, the physician must be aware of the possible noncontiguous multiple spine fractures when examine and treat the patients with spine fracture.
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Humanos , Accidentes de Trabajo , Diagnóstico , Incidencia , Corea (Geográfico) , Manifestaciones Neurológicas , Columna VertebralRESUMEN
Fifty percents of patient with achondroplasia present neurological disturbances of varying degree. Congenital narrowing of the spinal canal in achondroplastics seems to be the main cause of the cord disturbance, and there are several other causes such as prolapse of intervertebral discs, spondyloarthitic degenerative manifestations and wedging of vertebral body. Surgical treatment of the cord disturbance consist of anterior decompression with fusion and posterior decompression. We experienced L1-2 disc herniation in achondroplasia with rapid progression of neurologic symptoms and treated with posterior decompression. Two years after operation, the patient had good result.
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Humanos , Acondroplasia , Descompresión , Disco Intervertebral , Manifestaciones Neurológicas , Prolapso , Canal MedularRESUMEN
No abstract available.