Pipat Chiewvit

Cerebral venous thrombosis: diagnosis dilemma

Cerebral venous thrombosis is increasing common disease in daily practice with sharing clinical nonspecific symptoms. This disorder is potentially lethal but treatable, oftenly it was overlooked in both clinical and radiologic in routine practice. Whenever, clinical suspected, prompt investigation by noninvasive imaging Magnetic resonance (MR) or advanced modilities such as cerebral venous thrombosis (CVT), MRV (MR Venography) will helpful in prompt diagnosis and treatment. These imaging modalities may reveal either direct sign (visualization of intraluminal clot) and indirect signs (paranchymatous change, intracranial hemorrhage). By using of effective treatment will improve the prognosis of the patient. This review summarizes insights into etiology, incidence, imaging modalities and current of the treatment.

Chronic spinal cord injury treated with transplanted autologous bone marrow-derived mesenchymal stem cells tracked by magnetic resonance imaging: a case report

IntroductionIntrathecal transplantation is a minimally invasive method for the delivery of stem cells, however, whether the cells migrate from the lumbar to the injured cervical spinal cord has not been proved in humans. We describe an attempt to track bone marrow-derived mesenchymal stem cells in a patient with a chronic cervical spinal cord injury.Case presentationA 33-year-old Thai man who sustained an incomplete spinal cord injury from the atlanto-axial subluxation was enrolled into a pilot study aiming to track bone marrow-derived mesenchymal stem cells, labeled with superparamagnetic iron oxide nanoparticles, from intrathecal transplantation in chronic cervical spinal cord injury. He had been dependent on respiratory support since 2005. There had been no improvement in his neurological function for the past 54 months. Bone marrow-derived mesenchymal stem cells were retrieved from his iliac crest and repopulated to the target number. One half of the total cells were labeled with superparamagnetic iron oxide nanoparticles before transplantation to the intrathecal space between L4 and L5. Magnetic resonance imaging studies were performed immediately after the transplantation and at 48 hours, two weeks, one month and seven months after the transplantation. His magnetic resonance imaging scan performed immediately after the transplantation showed hyposignal intensity of paramagnetic substance tagged stem cells in the subarachnoid space at the lumbar spine area. This phenomenon was observed at the surface around his cervical spinal cord at 48 hours. A focal hyposignal intensity of tagged bone marrow-derived stem cells was detected at his cervical spinal cord with magnetic resonance imaging at 48 hours, which faded after two weeks, and then disappeared after one month. No clinical improvement of the neurological function had occurred at the end of this study. However, at 48 hours after the transplantation, he presented with a fever, headache, myalgia and worsening of his motor function (by one grade of all key muscles by the American Spinal Injury Association impairment scale), which lasted for 48 hours.ConclusionIntrathecal injection of bone marrow-derived stem cells at the lumbar spine level could deliver the cells to the injured cervical spinal cord. Transient complications should be observed closely in the first 48 hours after transplantation. Further study should be carried out to evaluate the result of the treatment.

Assessment Lumboperitoneal or Ventriculoperitoneal Shunt Patency by Radionuclide Technique: A Review Experience Cases

Hydrocephalus-related symptoms that worsen after shunt placement may indicate a malfunctioning or obstructed shunt. The assessment of shunt patency and site of obstruction is important for planning of treatment. The radionuclide cerebrospinal fluid (CSF) shunt study provides a simple, effective, and low-radiation-dose method of assessing CSF shunt patency. The radionuclide CSF shuntography is a useful tool in the management of patients presenting with shunt-related problems not elucidated by conventional radiological examination. This article described the imaging technique of ventriculoperitoneal (VP) shunt and lumbar puncture (LP) shunt. The normal finding, abnormal finding of completed obstruction and partial obstruction is present by our cases experience. The radiopharmaceutical (Tc-99m diethylenetriaminepentaacetic acid) was injected via the reservoir for VP shunt and via lumbar puncture needle in subarachnoid space for LP shunt, then serial image in the head and abdominal area. The normal function of VP and LP shunt usually rapid spillage of the radioactivity in the abdominal cavity diffusely. The patent proximal tube VP shunt demonstrates ventricular reflux. The early image of patent LP shunt reveals no activity in the ventricular system contrast to distal LP shunt reveals early reflux of activity in the ventricular system. The completed distal VP and LP shunt obstruction show absence of tracer in the peritoneal area or markedly delayed appearance of abdominal activity. The partial distal VP and LP shunt obstruction recognized by slow transit or accumulation of tracer at the distal end or focal tracer in the peritoneal cavity near the tip of distal shunt. The images of the normal and abnormal CSF shunt as describe before are present in the full paper. Radionuclide CSF shuntography is a reliable and simple procedure for assessment shunt patency.

Lateral cephalometric analysis and the risks of moderate to severe obstructive sleep-disordered breathing in Thai patients

PurposesThis cross-sectional study was aimed to compare lateral cephalometric parameters among patients with different severities of obstructive sleep-disordered breathing and to determine if there are radiographic variables that increase risk of moderate to severe obstructive sleep apnea (OSA).MethodsTen linear and 5 angular parameters of lateral cephalometry in 188 adult subjects which included 47 controls and 141 patients with OSA classified by apnea–hypopnea index (AHI) from level-I polysomnography, were analyzed. All radiographs were done under standardized processes and measured twice on separate occasions.ResultsThere were statistically significant differences between controls and patients with AHI ≥ 15 in parameters such as a distance from mandibular plane to hyoid (MP-H), posterior airway space (PAS), skull base angle (NSBA), a distance from posterior nasal spine to posterior pharyngeal wall (PNS-PP), and soft palate length (PNS-P), (p < 0.01). However, no significant difference was found between controls and mild OSA. Logistic regression analysis showed that only MP-H with cutoff point of ≥ 18 millimeters, NSBA ≤ 130°, and PAS ≤ 10 millimeters were independent cephalometric variables that increased risk of having AHI ≥ 15 compared to controls with adjusted odds ratio of 17.1, 8.3 and 4.2, respectively. Gender did not significantly associate with OSA severity in this analysis.ConclusionsPatients who had longer MP-H, narrower PAS and narrower NSBA than specific cutoff points significantly increased risks of moderate to severe OSA. Treatments that effectively improve these parameters, particularly at tongue base level (MP-H and PAS), may decrease the severity of disease.

Selective ophthalmic arterial infusion of chemotherapeutic drugs for recurrent retinoblastoma.

Introduced in 1988 by Kaneko and colleagues, selective ophthalmic arterial infusion of chemotherapeutic drug has recently gained more interest among retinoblastoma experts worldwide. The report showed that the procedure could be repeated up to 12 treatments without serious side effects. We report a 4-year-old girl with bilateral retinoblastoma. The left eye was enucleated for the group E disease. The right eye started with 3 retinal tumors (group C) was treated with systemic chemotherapy plus local therapy. Seven months after the last cycle of chemotherapy, the tumor recurred close to the fovea. Systemic chemotherapy was reinitiated without success. To avoid aggressive cryotherapy and external-beam radiotherapy, selective ophthalmic arterial infusion of chemotherapeutic drugs was performed for 15 sessions. The tumor responded partially without evidence of drug-induced retinal toxicity by the electroretinogram. Minor irregularities of the inner wall of supraclinoid portion of the internal carotid artery were observed only at the sixth session. Narrowing of the vascular lumen occurred on the last 2 sessions. We demonstrate that this technique when performed repeatedly could result in the anatomic changes of the small blood vessel. Careful follow-up is necessary for early detection of any serious consequences.

Reliability of intracerebral hemorrhage classification systems: A systematic review.

Background Accurately distinguishing non-traumatic intracerebral hemorrhage (ICH) subtypes is important since they may have different risk factors, causal pathways, management, and prognosis. We systematically assessed the inter- and intra-rater reliability of ICH classification systems. Methods We sought all available reliability assessments of anatomical and mechanistic ICH classification systems from electronic databases and personal contacts until October 2014. We assessed included studies’ characteristics, reporting quality and potential for bias; summarized reliability with kappa value forest plots; and performed meta-analyses of the proportion of cases classified into each subtype. Summary of review We included 8 of 2152 studies identified. Inter- and intra-rater reliabilities were substantial to perfect for anatomical and mechanistic systems (inter-rater kappa values: anatomical 0.78–0.97 [six studies, 518 cases], mechanistic 0.89–0.93 [three studies, 510 cases]; intra-rater kappas: anatomical 0.80–1 [three studies, 137 cases], mechanistic 0.92–0.93 [two studies, 368 cases]). Reporting quality varied but no study fulfilled all criteria and none was free from potential bias. All reliability studies were performed with experienced raters in specialist centers. Proportions of ICH subtypes were largely consistent with previous reports suggesting that included studies are appropriately representative. Conclusions Reliability of existing classification systems appears excellent but is unknown outside specialist centers with experienced raters. Future reliability comparisons should be facilitated by studies following recently published reporting guidelines.

Metal artifact reduction and image quality evaluation of lumbar spine CT images using metal sinogram segmentation.

Metal artifacts often appear in the images of computed tomography (CT) imaging. In the case of lumbar spine CT images, artifacts disturb the images of critical organs. These artifacts can affect the diagnosis, treatment, and follow up care of the patient. One approach to metal artifact reduction is the sinogram completion method. A mixed-variable thresholding (MixVT) technique to identify the suitable metal sinogram is proposed. This technique consists of four steps: 1) identify the metal objects in the image by using k-mean clustering with the soft cluster assignment, 2) transform the image by separating it into two sinograms, one of which is the sinogram of the metal object, with the surrounding tissue shown in the second sinogram. The boundary of the metal sinogram is then found by the MixVT technique, 3) estimate the new value of the missing data in the metal sinogram by linear interpolation from the surrounding tissue sinogram, 4) reconstruct a modified sinogram by using filtered back-projection and complete the image by adding back the image of the metal object into the reconstructed image to form the complete image. The quantitative and clinical image quality evaluation of our proposed technique demonstrated a significant improvement in image clarity and detail, which enhances the effectiveness of diagnosis and treatment.

Patterns of the Cranial Venous System from the Comparative Anatomy in Vertebrates: Part III. The Ventricular System and Comparative Anatomy of the Venous Outlet of Spinal Cord and Its Homology with the Five Brain Vesicles

SUMMARY Ontogenetically, the ventricular venous systemmay develop in order to drain the gray matter(cells of the mantle layer of the neural tube) which migrates dorsally. On primitive brain vesicles of submammals especially fish, amphibianand reptile, the ventricular venous system is the major venous collector located on the middorsal surface, in between the meningeal layers comparable to the subarachnoid space in mammals. The ventricular venous system functions as a major drainage system for the brain vesicles in these submammals but its role decreases when the other two venous systems develop. Concerning the route of venous exit from the brain vesicles, we found that it resembles the spinal cord but could not be found all the way along the brain vesicles.Ontogenetically, the ventricular venous system may develop in order to drain the gray matter (cells of the mantle layer of the neural tube) which migrates dorsally. On primitive brain vesicles of submammals especially fish, amphibian and reptile, the ventricular venous system is the major venous collector located on the mid-dorsal surface, in between the meningeal layers comparable to the subarachnoid space in mammals. The ventricular venous system functions as a major drainage system for the brain vesicles in these submammals but its role decreases when the other two venous systems develop. Concerning the route of venous exit from the brain vesicles, we found that it resembles the spinal cord but could not be found all the way along the brain vesicles.

Two patients with rare causes of Weber's syndrome.

We report two patients with rare causes of Webers syndrome and review the relevant literature. The first patient presented with Webers syndrome caused by a partially thrombosed giant aneurysm of the posterior cerebral artery. The second patient was an immunocompetent patient who presented with progressive hemiparesis and subsequently developed Webers syndrome. Primary central nervous system lymphoma (PCNSL) was eventually diagnosed. To our knowledge, the association between Webers syndrome and PCNSL is rare.

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.