Interventional Neuroradiology in Thailand: 1989–1997

In 1979 the Siriraj team in Bangkok began exploring a field that was then new in Thailand, i. e. interventional neuroradiology. This first phase consisted mostly in self-training and foreign exposure.

It included experimental work with animal models, as well as early clinical trials designed to assess our skills in particle embolisation and the ligated and detachable balloon techniques. In 1990 a new phase started.

Essential techniques were acquired in collaboration with the neurovascular unit of Bicêtre Hospital in France during a three year training programme. Throughout this period, the support of the Association Médicale Franco-Asiatique (AMFA) and the French foreign affairs department proved vital. Our department progressively became a referral centre for the different techniques used in embolisation (balloons, glue…) and for various vascular lesions of the brain, the head and neck region, and spinal cord diseases.

Within Mahidol University, the Ramathibodi and Prasat Hospital centres started the same interventional neuroradiology training program in 1995; they benefited from the same tutors and connections as Siriraj. In 1996, the newly acquired biplane DSA machines in both centres enabled us to improve the treatment of arteriovenous malformations - using the glue technique –, intracranial aneurysm - using GDC-coils -, clot lysis, angioplasty… etc.

According to international recommendations, the critical mass we reached in 1997 in terms of number of patients and interventions, allows us to offer training in endovascular techniques to junior neuroradiologists at Mahidol university.

Magnetic Resonance Imaging of Asians with Multiple Sclerosis was Similar to that of the West

Magnetic resonance imaging (MRI) of the brain is the most important paraclinical diagnostic test in multiple sclerosis (MS). The appearance of MRI in Asians with MS is not well defined. We retrospectively surveyed the first brain and spinal cord MRI in patients diagnosed to have MS, according to Poser's criteria in seven regions throughout Asia to define the MRI changes among Asians with MS. There were 101 patients with first brain, and 86 with first spinal cord MRI, 66 of whom had both. The brain MRI showed a mean of 17 lesions per patient in T2 weighted images, mostly asymptomatic. Almost all the lesions were in the white matter, particularly in the juxtacortical, deep and periventricular white matter. A third of the lesions were greater than 5 mm, 14% enhanced with gadolinium. There were more supratentorial than infratentorial lesions at a ratio of 7.5: 1. Ninety five percent of the spinal cord lesions were in cervical and thoracic regions, 34% enhanced with gadolinium. The lesions extended over a mean of 3.6 +/- 3.3 vertebral bodies in length. Fifty (50%) of the brain and 54 (63%) of the spinal MRI patients had the optic-spinal form of MS. The MRI of the optic-spinal and classical groups of patients were similar in appearance and distribution, except that the optic-spinal MS patients have fewer brain but longer and more severe spinal cord lesions. In conclusion, the brain and spinal cord MRI of Asian patients with MS was similar to that of the West, although, in this study, Asian MS patients had larger spinal cord lesions.

Clinical Application of Susceptibility Weighted Imaging: Exploring from Routine Service

To evaluate the usefulness of susceptibility weighted imaging (SWI) in clinical brain MRI. Retrospective study was performed after approval from institution Ethical Committee. The brain MRIs with SWI were selected from data base of the radiology department. Only cases with no abnormality in extra-axial location were included into the study. Two neuroradiologists revealed the images without knowledge of patients' history and diagnosis. The SWI was first interpreted. Then conventional MRI (cMRI) was interpreted after finishing data collection from SWI. Clinical data and final diagnosis were collected from information given on requested forms and followed up imaging studies. Descriptive analysis was performed. From January 2007 to December 2009, 82 cases were satisfied the inclusion criteria. There were 40 males and 42 females with age 7–79 years old (means = 47.45). The final diagnosis were normal brain imaging 4 cases (4.9%), dementia/atypical Parkinson disease 2 cases (2.4%), cerebrovascular disease 24 cases (29.3%), parenchymal brain tumors 35 cases (42.7%), infection 4 cases (4.9%), multiple sclerosis (MS) 6 cases (7.3%) and inconclusive diagnosis 7 cases (8.5%). The abnormalities found on SWI were related to cMRI in 67 cases (81.7%). Three cases (3.7%) had lesions on SWI not demonstrated on cMRI The information got from SWI added on cMRI for interpretation and diagnosis in 43 cases (52.4%). SWI were shown more detectable microbleed and changing visualization of cortical and transmedullary veins. Microvascular structure inside the mass was demonstrated on SWI in brain tumor group. The increased transmedullary veins on SWI helped to confirm the non-neoplastic lesions. In selected cases with suspected or diagnosis of vascular disease and tumor, SWI added more information on cMRI especially microbleed and microvascular structure.

Scrub typhus: chest radiographic and clinical findings in 130 Thai patients

OBJECTIVE

To describe chest radiographic findings and their clinical correlation in patients with scrub typhus diagnosed in Thailand and to determine abnormalities that assist in the diagnosis of scrub typhus.

MATERIAL AND METHOD

Between July 2001 and December 2002, 130 patients with scrub typhus admitted to three hospitals in the northeastern Thailand were studied. Data of clinical presentations and chest radiographic findings, reviewed by two radiologists who were unaware of the final diagnosis, were analyzed.

RESULTS

There were 33 women, 97 men; age range, 11-92 years; median age, 45 years old. Pulmonary symptoms occurred in 61.5% of the patients and eschar was found in 33.1%. Hepatic dysfunction occurred in 58.5% and cardiovascular dysfunction in 33%. Pulmonary involvement was the major presentation in 41.5%. Acute respiratory distress syndrome developed in 7 patients. Overall 5 patients died. The initial radiography showed abnormalities in 64.6% of the patients. Common radiographic abnormalities included bilateral reticular opacities (48.5%), cardiomegaly (28.5%), congestive heart failure (18.5%), air space nodules (13.1%), and pleural effusion (10.8%). Significant association between chest radiographic abnormalities and hepatic and cardiovascular dysfunction were documented.

CONCLUSION

Chest radiography should be included in the initial evaluation of patients with suspected scrub typhus. Bilateral reticular infiltration, with or without cardiomegaly or congestive heart failure, was the most frequent radiographic finding of scrub typhus.

Moyamoya syndrome: post cranial irradiation of pineal gland tumor

SUMMARY

A right-handed eight-year-old boy, with headache, vomiting and positive parinaud's sign was diagnosed as having a pineal gland tumor which histopathological section from surgical biopsy revealed to be a germinoma. The patient underwent ventriculoperitoneal shunt for obstructive hydrocephalus. Thereafter, he received cranial irradiation as definitive treatment. He was well and went back to school until five years later he developed a transient ischemic attack. Cranial magnetic resonance imaging showed a complete cure of the pineal tumor without any other specific abnormality. Eight months later he had an episode of stroke which was demonstrated by cranial computed tomography as acute left cerebral infarction in the middle cerebral artery territory. Cerebral angiography showed Moyamoya syndrome.