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Jiraporn Laothamatas

Publications and source records attributed to Jiraporn Laothamatas.

16 recordsLinked to original sources
PubMed2006

Rabies.

Despite increases in our understanding of rabies pathogenesis, it remains an inevitably fatal disease. Lack of awareness, low level of political commitment to rabies control, and failure to recognize and correlate clinical, laboratory, and neuroimaging features contribute to continuing deaths. Clinical symptomatology, once believed to be unique, may be variable, even in patients associated with lyssaviruses of the same genotype. This article discusses virus transport, the role of virus and host response mechanisms in relation to protean clinical manifestations, and mechanisms responsible for relative intactness of consciousness in human rabies. Differential involvement of the anterior horn cell in furious rabies and the peripheral nerve in paralytic rabies is summarized. Escape mechanisms from host defenses explain why a fatal outcome is unavoidable regardless of therapy. Neuroprotective treatment, using a coma-induction regimen, proves not to be beneficial. Survival of patients with excellent recovery relies on early innate and adaptive immunity plus adequate intensive care support.

Humans↗
PubMed2006

Accuracy of sixteen-slice CT scanners in detected coronary artery disease.

BACKGROUND: The coronary artery disease, now, the incidence is increasing in both developed and developing countries. The investigation is evoluted and non-invasive multislice CT scanners have been used more frequently, although the gold standard is still the coronary angiography. OBJECTIVE: To investigate the accuracy in detected coronary artery disease by using 16-slice CT scanners compared to the conventional coronary angiography. MATERIAL AND METHOD: Fifty-five patients were 43 males, 12 females, median aged 62 years (43-82 years), and average heart rates 67 beats/minute (46-147 beats/minute) had the ECG-gated CT angiography followed by coronary angiography in 3 months. The ECG-gated CT angiography was performed by using 16-slice MSCT detector (0.42-s rotation time, 16 x 0. 75-mm detector collimation). RESULTS: All patients were classified into two major groups; one was significant coronary artery stenosis which was designed by stenosis at least 50% and the other was non-significant stenosis which was designed by normal or stenosis less than 50%. The site having blooming artifact due to calcification that causes complete obliteration of the lumen or having significant motional artifacts was ruled out. There were 285 evaluable sites in 19 patients with high heart rates, more than 70 beats/minute. The sensitivity, specificity, and accuracy in significant stenosis were 72.9%, 99.6%, and 94.0% respectively. In 36 patients with a lower heart rate, there were 563 evaluable sites, the sensitivity was 86.5%, specificity was 98.5%, and accuracy was 96.6%. The overall showed 81.1% of sensitivity, 98.9% of specificity, and 95.8% of accuracy. CONCLUSION: The accuracy of the 16-slice CT angiography for patients suspected of having coronary artery disease was high. However, blooming artifacts from the calcium, respiratory artifacts, and small size of the distal and branching artery still caused limited luminal assessment. These problems have challenged the new coming generation of MDCT.

Adult↗
PubMed2006

MRI findings of the cavernous sinus metastasis with inferior extension mimicking a nasopharyngeal carcinoma with cavernous sinus invasion.

The authors report the MRI findings in a patient with cavernous sinus metastasis with inferior extension to the nasopharynx, mimicking imaging findings of the advanced nasopharyngeal cancer with the skull base, and intracranial extension. Findings of denervative atrophy of the masticator muscles and obstruction of the Eustachian tube resulting in fluid retention of mastoid air cells are seen in both processes.

Cavernous Sinus↗
PubMed2006

Cardiovascular examination with 3.0 Tesla magnetic resonance imaging: first 100 cases at Ramathibodi Hospital.

BACKGROUND: Cardiovascular magnetic resonance imaging (CMR) has been utilized for diagnosis in various cardiovascular diseases and most of those were performed on a 1.5 Tesla CMR system. Recently, a 3.0 Tesla magnetic resonance imaging system has been introduced into clinical practice, however the clinical experience on cardiovascular examination using this system is limited. Therefore, the authors' institution has integrated a team for developing a CMR program on this 3.0 Tesla system. OBJECTIVE: To describe the authors' experience on the 3.0 Tesla CMR system. MATERIAL AND METHOD: The data on patients referred to the authors' CMR unit between August 2004 and October 2005 were reviewed. RESULTS: One hundred patients were referred for CMR examination. The mean age was 56 years (2 month - 85 years) and 65 patients were male. The most common indication was to assess coronary artery disease (64 patients). The performed examination was divided into cardiac structure and function assessment (39%), stress testing (23%), coronary magnetic resonance angiography (13%), myocardial viability assessment (12%), magnetic resonance angiography (9%), and flow assessment (4%). CONCLUSION: The present study highlights that comprehensive assessment of various cardiovascular diseases can be performed on the 3.0 Tesla CMR system.

Adolescent↗
PubMed2005

Difference in neuropathogenetic mechanisms in human furious and paralytic rabies.

Whereas paralysis is the hallmark for paralytic rabies, the precise pathological basis of paralysis is not known. It is unclear whether weakness results from involvement of anterior horn cells or of motor nerve fibers. There is also no conclusive data on the cause of the neuropathic pain which occurs at the bitten region, although it has been presumed to be related to sensory ganglionopathy. In this study, six laboratory-proven rabies patients (three paralytic and three furious) were assessed clinically and electrophysiologically. Our data suggests that peripheral nerve dysfunction, most likely demyelination, contributes to the weakness in paralytic rabies. In furious rabies, progressive focal denervation, starting at the bitten segment, was evident even in the absence of demonstrable weakness and the electrophysiologic study suggested anterior horn cell dysfunction. In two paralytic and one furious rabies patients who had severe paresthesias as a prodrome, electrophysiologic studies suggested dorsal root ganglionopathy. Postmortem studies in two paralytic and one furious rabies patients, who had local neuropathic pain, showed severe dorsal root ganglionitis. Intense inflammation of the spinal nerve roots was observed more in paralytic rabies patients. Inflammation was mainly noted in the spinal cord segment corresponding to the bite in all cases; however, central chromatolysis of the anterior horn cells could be demonstrated only in furious rabies patient. We conclude that differential sites of neural involvement and possibly different neuropathogenetic mechanisms may explain the clinical diversity in human rabies.

Adult↗
PubMed2004

Expanding the phenotypic spectrum of Lenz-Majewski syndrome: facial palsy, cleft palate and hydrocephalus.

We report a sporadic case of Lenz-Majewski syndrome (LMS) with newly recognized manifestations including facial palsy, cleft palate and hydrocephalus developing later in infancy. The clinical course of the patient and neuroimaging studies are described. Increased intracranial pressure was recognized and treated early with the aim of preventing neurological morbidity.

Abnormalities, Multiple↗
PubMed2004

Fractionated stereotactic radiotherapy for bilateral vestibular schwannomas associated with neurofibromatosis type 2: early experiences in Ramathibodi Hospital.

PURPOSE: To evaluate the rates of tumor control and useful hearing preservation in patients with bilateral vestibular schwannomas (VSs) associated with neurofibromatosis type 2 (NF-2) treated with fractionated stereotactic radiotherapy (FSRT). MATERIAL AND METHOD: From August 1998--December 2002 there were 5 patients with NF-2 who underwent FSRT (Linac-based system) for bilateral CP angle tumors. Median age was 28 (18-47) years. Median tumor volume was 5.4 (2.2-9.4) cc. Eight lesions received a marginal dose of 44.2-59.9 (median = 46.2) Gy in 25-33 fractions. The other 2 lesions received 4.4 and 4.9 Gy/fraction for 6 fractions in 3 and 2 weeks. Median follow-up was 19 (14-44) months. RESULTS: Radiographic and clinical tumor control rate was 90%. One lesion progressed at 7 months after FSRT and was completely resected Of the 5 lesions with Gardner-Robertson class I-II hearing before FSRT 2 (40%) retained useful hearing at the last follow-up. One patient had left facial spasm at 10 months after FSRT which gradually improved. No patient had facial palsy, facial numbness or pain. CONCLUSIONS: FSRT provided good tumor control and hearing preservation rate in NF-2 patients with minimal morbidity. However, a longer follow-up is needed to evaluate long term results.

Adolescent↗
PubMed2004

Magnetic resonance imaging of the brain in epileptic pediatric patients: review of the experience in Ramathibodi Hospital.

OBJECTIVE: To review a series of epileptic children referred for MR imaging and correlate the structural abnormalities from the MRI findings with clinical data and EEG. MATERIAL AND METHOD: Retrospective review of MRI of the brain performed in children, aged less than 15 years with epilepsy at Ramathibodi Hospital from January 1999 to December 2002 was done. There were 100 children (57 girls, 43 boys) with epilepsy, age range from one month to 14 years, mean 7 years and 5 months. Diagnosis of seizure type and epilepsy were classified according to clinical presentation and EEG. RESULTS: There were 16 children with primary generalized seizure, 79 children with partial or complex partial seizures with or without secondary generalization. The remaining 5 children had a specific syndrome. The most common etiology of all patients was congenital disease, especially cortical dysplasia. Among children with partial with or without generalization, cortical dysplasia was the most common finding (31%). Mesial temporal sclerosis and combined cortical dysplasia with mesial temporal sclerosis were found in 24% and 13.9%, respectively. Most of the disease categories showed significant concordance of the EEG to the MRI findings, except infectious disease. CONCLUSION: The most common etiology of epilepsy in children under 15 years old was cortical dysplasia. For children with partial or complex partial seizure, cortical dysplasia was the most common etiology followed by mesial temporal sclerosis and combined cortical dysplasia with mesial temporal sclerosis, respectively. MRI provides precise etiologic classifications of epilepsy.

Adolescent↗
PubMed2003

Choroidal osteoma in Oriental patients.

BACKGROUND: Choroidal osteoma is a rare tumour of the choroid. This is the first report of cases of choroidal osteoma in Thai patients. OBJECTIVE: To report the clinical characteristics, imaging findings and long-term follow-up of choroidal osteoma in four Oriental patients. METHOD: Four cases of choroidal osteoma were observed for 5 years or more. RESULTS: All patients were young female patients whose ages ranged from 24 to 37 years. Three were unilateral and one was bilateral. The tumors were located at the juxtapapillary and macular area with overlying serous retinal detachment. Two patients had previous thyroid diseases and one was pregnant when the tumors were diagnosed. Osteoma did not develop in the vicinity of posterior staphyloma of high myopic eyes. Echography showed acoustic features of a plano-convex sonically dense lesion with high reflectivity echoes which persisted despite lower system sensitivity. None had subretinal neovascularization. Subretinal fluid disappeared spontaneously within one to 14 months in three patients. Gradual growth of the tumor in a pseudopodium manner developed from two to six years after initial examination. Decalcification occurred spontaneously or after laser ablation. CONCLUSIONS: The authors presented four Oriental patients with choroidal osteoma who were observed for at least 5 years. Echography is the best method for identifying this lesion and has unique acoustic features. Subretinal fluid can be seen in the absence of subretinal neovascularization and resorbs spontaneously. Decalcification occurred as a natural process or after laser ablative treatment. Hormonal changes may implicate the development of this tumor.

Adult↗
PubMed2002

Human rabies: a disease of complex neuropathogenetic mechanisms and diagnostic challenges.

Rabies is inevitably fatal and presents a horrifying clinical picture. Human rabies can manifest in either encephalitic (furious) or paralytic (dumb) forms. The brainstem is preferentially involved in both clinical forms, though there are no clinical signs of brainstem dysfunction. Differences in tropism at the inoculation site or the CNS, in the route of spread, or in the triggering of immune cascades in the brainstem may account for clinical variation. Rabies still poses diagnostic problems, particularly the paralytic form, which closely resembles Guillain-Barré syndrome, or when a patient is comatose and cardinal signs may be lacking. Molecular methods allow reliable detection of rabies-virus RNA in biological fluids or tissue before death. Deviations from the recommendations on prophylaxis of the World Health Organization lead to unnecessary loss of life. To date, attempts to treat human rabies have been unsuccessful.

Animals↗
PubMed2002

Pitfall of electron beam computed tomography angiography in diagnosis of subclavian steal syndrome.

A patient presented with vertebrobasilar insufficiency during exertion. Vertebral duplex and transcranial Doppler ultrasonography showed reversal of flow in both intracranial and extracranial vertebral and basilar arteries, suggesting bilateral subclavian and vertebrobasilar steal. Electron beam computed tomography angiography (CTA) showed no evidence of subclavian artery stenosis including normal vertebral artery origin on both sides. However, digital subtraction angiography revealed complete occlusion of both subclavian arteries with retrograde flow from both vertebral and basilar arteries to reconstitute both subclavian arteries. This false-negative finding on CTA in detection of subclavian steal syndrome (SSS) is due to inappropriate contrast administration technique and postprocessing method, inability to differentiate flow direction, and lack of hemodynamic time sequences. This study demonstrates a pitfall of CTA in diagnosis of SSS compared to more reliable hemodynamic information obtained by duplex and transcranial Doppler ultrasonography, and digital subtraction angiography.

Angiography, Digital Subtraction↗
PubMed2002

Detection of JC virus infection in progressive multifocal leukoencephalopathy: the first documented case in Thailand.

Progressive Multifocal Leukoencephalopathy (PML) is a demyelinating brain disease caused by human polyoma JC virus (JCV). This disease is an important cause of morbidity and mortality in AIDS patients. Definite diagnosis currently requires a brain biopsy. PCR for JCV of CSF, an emerging diagnostic tool, has a high specificity for the diagnosis of PML in patients with characteristics on clinical and neuroradiological findings. The authors report a 36-year-old woman who presented with prolonged fever, progressive weakness, and slow speech for 2 months. Clinical features and MRI findings were compatible with PML. Qualitative PCR for JCV of CSF showed a positive result. This report emphasizes the yield of PCR, the CSF for JCV in a diagnosis of PML, which may reduce the need for a brain biopsy in such cases.

Acquired Immunodeficiency Syndrome↗
PubMed2002

Localization of sensorimotor cortex by using functional magnetic resonance imaging: comparison between finger tapping and palm scratching in normal volunteer.

The purpose of this study was to compare the location and intensity of activation of the sensorimotor cortex between finger tapping and palm scratching paradigms in normal volunteers and to consider using passive task instead of motor task in patients who are unable to perform motor task. Multishot echo-planar T2*-weighted imaging sequences at the level of the sensorimotor cortex were performed in axial plane during finger tapping and palm scratching paradigms in 13 normal volunteers. The authors found that the location of activation was slightly posterior only in bilateral passive task compared to bilateral motor task but there was no statistical significance. However, this observation was not seen in unilateral tasks. The intensity of activation of both motor and passive tasks was comparable. The authors conclude that in normal volunteers passive task (palm scratching) can be used instead of motor task (finger tapping) to localize the location of the sensorimotor cortex.

Adult↗
PubMedDate not supplied

Bilateral sudden sensorineural hearing loss as a presentation of metastatic adenocarcinoma of unknown primary mimicking cerebellopontine angle tumor on the magnetic resonance image.

This report presented a case of sudden profound bilateral sensorineural hearing loss with progressive facial diparesis in a 64-year-old woman. The magnetic resonance imaging (MRI) finding mimicked bilateral masses in the cerebellopontine angle (CPA) in an absence of clinical meningeal or parenchymal involvements at the first presentation. Surgical biopsy and histopathologic finding identified masses secondary to direct invasion of adenocarcinoma of gastrointestinal origin. Many investigations could not discover the primary site of the metastatic adenocarcinoma. Grave prognosis was observed in all cases reported including ours; the patient died 10 weeks after onset of symptoms.

Adenocarcinoma↗
PubMedDate not supplied

MR imaging in human rabies.

BACKGROUND AND PURPOSE: Whether human rabies of different forms, encephalitic (furious) and paralytic (dumb), share similar MR imaging patterns is unknown. We assessed the diagnostic value of MR imaging in both forms of the disease and compared the clinical and neuroimaging findings. METHODS: Three patients with paralytic and two with encephalitic rabies were examined during preserved or deteriorated levels of consciousness. Six MR examinations of the brain, three of the spinal cord, and one of the brachial plexus were performed with a 1.5-T superconducting magnet. RESULTS: No difference was noted between the MR findings in both clinical forms of human rabies. Nonenhancing, ill-defined, mild hyperintensity changes in the brain stem, hippocampi, hypothalami, deep and subcortical white matter, and deep and cortical gray matter were demonstrated on T2-weighted images in the noncomatose patients with rabies. Enhancement along the brachial plexus of the bitten arm was noted in one patient with encephalitic rabies who at that time had only local neuropathic pain symptoms. Enhancement with gadolinium-based contrast material was seen at the hypothalami, brain stem nuclei, spinal cord gray matter, and intradural cervical nerve roots only when the patients became comatose. CONCLUSION: Both forms of human rabies share a similar MR imaging pattern. Such pattern and the lack of enhancement in a noncomatose patient with suspected encephalitis may differentiate rabies from other viral encephalitides.

Adult↗