• Progress in Medical Physics
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• v.5 no.1
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• pp.55-66
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• 1994

After proving home-made imaging pulse sequences including tailored RF pulse by phantom, susceptibility-contrast-enhanced MR venograms of cat brain were obtained using tailored RF gradient-echo(TRGE) method. Sagittal MR imaging of the cat brain obtained by TRGE technique shows several veins, for example, dorsal sagittal sinus, straight sinus, vein of corpus callosum and internal cerebral vein, etc., compared with cats anatomical figure. Tailored RF waveform was generated by PASCAL language in ASPECT 3000 computer(Switzland, Bruker). Rectangular-shaped slice profile with bi-linear ramp function as phase distribution in the slice, at which maximum value was 2$\pi$, was fourier transformed to make tailored RF pulse. Experimental MR imaging parameters were TR/TE=205/10 msec, slice thickness TH=7mm, maxtrix size=256$\times$256, in-plane resolution=0.62$\times$0.31mm$^2$, and field of view(FOV)=8cm for both conventional gradient-echo(GE) imaging and TRGE imaging techniques.

• Clinical and Experimental Pediatrics
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• v.52 no.1
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• pp.124-128
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• 2009

Pulmonary arteriovenous malformations (PAVMs) are direct communications between pulmonary arteries and pulmonary veins, resulting in right-to-left shunts that may cause cyanosis, dyspnea, and digital clubbing. Neurological complications such as intracerebral hemorrhage or brain abscess may result from cerebral thrombosis or emboli. In most cases, they remain unrecognized until the late teenage years. Here, we report a case of a 6-year-old boy who presented with perioral cyanosis, digital clubbing, and dyspnea on exertion. A plain chest X-ray showed a focal nodular opacity in the right lower lobe (RLL), and a diagnosis of a large PAVM in the RLL was confirmed by chest computed tomography. A right lower lobectomy was successfully performed without any complications. Although their incidence in children is low, PAVMs should be suspected as a possible cause of cyanosis and dyspnea of non-cardiac origin, and should be treated promptly to prevent further neurological complications.

• The Korean Journal of Nuclear Medicine Technology
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• v.16 no.1
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• pp.17-26
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• 2012

Purpose: This study mainly focuses on the patients treated with chemically stable radiopharmaceutical product $^{99m}Tc$-HMPAO (d,l-hexamethylpropylene amine oxime) which yielded reduced image quality due to a decreased brain extraction rate. $^{99m}Tc$-HMPAO will be examined further to determine whether this product may be accounted as a factor for this cause. Material and Methods: From January 2010 until December 2010, out of 272 patients who were all subjected to $^{99m}Tc$-HMPAO brain blood flow SPECT scans resulting from Cerebral Infarction; 23 patients(ages $55.3{\pm}9$, 21 males, 3 females) with decreased tissue extraction rate were examined in detail. The radiopharmaceutical product $^{99m}Tc$-HMPAO was used on patients with normal brain tissue exchange rate as well as those with reduced rate in order to prove its' chemical stability. The patients' age, sex, blood pressure, existence of diabetes, drug use, current health status, known side effects from CT/MRI, examination of the patients' past SPECT before/after images were accounted to determine the factors and correlations affecting the rate of blood tissue extractions. Result: After multiple linear regression analysis, there were no unusual correlations between the 6 factors excluding sex, and before/after examination images. Male subjects showed reduced brain tissue extraction rate than the females ($p$ > 0.05) 91.3% male, 8.7% female. Wilcoxon Matched-Pairs Signed-Ranks Test was used on the before/after images which yielded a value of 0.06, which did not indicate a significant amount of difference on the 2 tests ($p$ > 0.05). As a result, the before/after images indicated similar brain tissue extraction rates, and there were variations depending on the individual patient. Conclusion: The effects of the chemically stable radiopharmaceutical product $^{99m}Tc$-HMPAO depended on the patient's personal characteristics and status, therefore was considered to be a factor in reducing brain tissue extraction rate. The related articles of $^{99m}Tc$-HMPAO cerebral blood flow SPECT speculates a cerebrovascular disease and factors resulting from portal veins, and it was not possible to pin point the exact cause of decreasing brain tissue extraction rate. However, the $^{99m}Tc$-HMPAO cerebral blood flow SPECT scan proved to be extremely useful in tracking and inspecting brain diseases, as well as offering accurate results from patients suffering from reduced brain tissue extraction rates.

• Journal of Korean Neurosurgical Society
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• v.30 no.10
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• pp.1200-1209
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• 2001

Objective : A thorough understanding of the related venous structure is mandatory for successful removal of the petroclival meningiomas. This study was planned to investigate the guideline for safe ligation and incision of transverse or sigmoid sinuses and the importance of drainage pattern of vein of $Labb{\acute{e}}$ in surgical removal of petroclival meningiomas. Patients and Methods : The authors reviewed the venogram of the consecutive 37 cases of petroclival meningiomas and retrospectively analyzed their surgical findings. The drainage pattern of confluence of Herophili was classified as Type A(confluent & equal on both sides), Type B(confluent & non-dominant on tumor side), Type C(confluent & dominant on tumor side) and Type D(unilateral drainage only) as these findings gave the information on safe ligation and resection of the sinus. Usefulness of intraoperative test clamping of sinus for safe ligation was also reviewed. The vein of $Labb{\acute{e}}$ was analyzed with respect to its draining point and its collaterals to other superficial veins. Results : Contraindications of the sinus ligation and resection according to the drainage pattern at the confluence of Herophili were Type C(n=10, 27%)and Type D(n=4, 11%). Patients with Type A(n=12, 32%)and Type B(n=11, 30%) were tolerable to sinus ligation ipsilateral to tumor, if the test clamping proved to be safe. Identification of no brain swelling, after intraoperative test clamping of the sinus for more than 30 minutes performed in 7 out of 11 cases, was a reliable indicator of safe sinus ligation. The drainage pattern of the vein of $Labb{\acute{e}}$, especially low-lying type, could predict the possibility of postoperative hemorrhage and infarction. Its drainage into tentorium or superior petrosal sinus, however, made the transtentorial approach impossible, leading to restricted operative field. Conclusion : For a successful removal of the petroclival meningiomas preoperative venogram should be examined carefully. The extent of exposure in a planned approach can be estimated by analyzing the variation of sinuses and the drainage pattern of vein of $Labb{\acute{e}}$.

• Korean Journal of Acupuncture
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• v.20 no.3
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• pp.35-47
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• 2003

Objective : The purpose of this study was to investigate the significance of the Oriental medical treatment using He-Ne laser with low energy intravascular Laser Irradiation of Blood(ILIB) through the superficial venules. Methods : The investigation of details connected with the superficial venules in the literature is performed. The investigation of details connected with the pricking blood techniques through the superficial venules in the literature is performed. The classification of the pricking blood techniques through the superficial venules by the blood-letting puncture methods in the literature is performed. The arrangement of domestic clinical treatises on the effectiveness of medical treatment using He-Ne laser with low energy ILIB through the superficial venules is performed. The consideration on the methodology for the improvement of the clinical effectiveness of He-Ne laser with low energy ILIB through superficial venules is performed. Results and Conclusions : The superficial venules are small arteries, veins and capillaries in the superficial region of the human body. In the pricking blood techniques, there are the blood-letting puncture using the implement of acupuncture to the Jing points, Extra points and superficial blood vessels and the acupuncture using the Hirudo. The methods of the blood-letting puncture are classified into the venous blood-letting puncture, the pricking , the picking out white fiber-like substances from the subcutaneous tissue, the cluster needling, the scattered needling, the blood-letting puncture of the tready collateral branch of the large channel and the blood-letting puncture of skin. The He-Ne laser with low energy ILIB through the superficial venules belongs to the Oriental medical treatment as the method of the blood-letting puncture in the vein of cubital fossa. The He-Ne laser with low energy ILIB has an effect on hyperfibrinogenemia, hyperlipidemia, speech and motor dysfunction in the case of cerebral infarction, headache, dizziness, pain and numbness. It is considered that fundamental research on the biological change of the human body, the experimental animal and the unicellular animal, and research on the effectiveness and the safety, and the development of He-Ne laser with low energy ILIB of an effective wavelength range are necessary.

• Investigative Magnetic Resonance Imaging
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• v.20 no.2
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• pp.105-113
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• 2016

Purpose: Susceptibility vessel sign (SVS) on gradient echo image, which is caused by MR signal loss due to arterial thrombosis, has been reported in acute middle cerebral artery (MCA) infarction. However, the reported sensitivity and diagnostic accuracy of SVS have been variable. Susceptibility-weighted imaging (SWI) is a newly developed MR sequence. Recent studies have found that SWI may be useful in the field of cerebrovascular diseases, especially for detecting the presence of prominent veins, microbleeds and the SVS. The purpose of this study was to evaluate the diagnostic values of SWI for the detection of hyperacute MCA occlusion. Materials and Methods: Sixty-nine patients (37 males, 32 females; 46-89 years old [mean, 69.1]) with acute stroke involving the MCA territory underwent MR imaging within 6 hours after the symptom onset. MR examination included T2, FLAIR (fluid-attenuated inversion recovery), DWI, SWI, PWI (perfusion-weighted imaging), contrast-enhanced MR angiography (MRA) and contrast-enhanced T1. Of these patients, 28 patients also underwent digital subtraction angiography (DSA) within 2 hours after MR examination. Presence or absence of SVS on SWI was assessed without knowledge of clinical, DSA and other MR imaging findings. Results: On MRA or DSA, 34 patients (49.3%) showed MCA occlusion. Of these patients, SVS was detected in 30 (88.2%) on SWI. The sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of SWI were 88.2%, 97.1%, 96.8%, 89.5% and 92.8%, respectively. Conclusion: SWI was sensitive, specific and accurate for the detection of hyperacute MCA occlusion.

• Journal of the Korean Society of Radiology
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• v.82 no.6
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• pp.1619-1627
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• 2021

Central venous stenosis is a relatively common complication in hemodialysis patients; however, jugular venous reflux (JVR) and increased intracranial pressure are rare, and associated progressive visual disturbance was reported in only a few cases. Here, we report a case of JVR with visual disturbance and increased intracranial pressure. Notably, the MRI was accompanied by a dilatation of the superior ophthalmic vein, which was mistaken for a cavernous sinus dural arteriovenous fistula (CSdAVF). The patient had JVR on time-of-flight MR angiography (TOF-MRA) and severe stenosis of the left brachiocephalic vein on conventional angiography. After balloon angioplasty for central venous stenosis, he was discharged after improvement of his visual disturbance. Although JVR due to central venous stenosis and CSdAVF might show similar symptoms, treatment plans are different. Therefore, it is important to distinguish radiologically based on a thorough review of MRI and TOF-MRA and confirm the central venous stenosis on cerebral angiography for the accurate diagnosis.