Risk of thyroid cancer in a lung cancer screening population of the National Lung Screening Trial according to the presence of incidental thyroid nodules detected on low-dose chest CT

Purpose@#This study evaluated thyroid cancer risk in a lung cancer screening population according to the presence of an incidental thyroid nodule (ITN) detected on low-dose chest computed tomography (LDCT). @*Methods@#Of 47,837 subjects who underwent LDCT, a lung cancer screening population according to the National Lung Screening Trial results was retrospectively enrolled. The prevalence of ITN on LDCT was calculated, and the ultrasonography (US)/fine-needle aspiration (FNA)–based risk of thyroid cancer according to the presence of ITN on LDCT was compared using the Fisher exact or Student t-test as appropriate. @*Results@#Of the 2,329 subjects (female:male=44:2,285; mean age, 60.9±4.9 years), the prevalence of ITN on LDCT was 4.8% (111/2,329). The incidence of thyroid cancer was 0.8% (18/2,329, papillary thyroid microcarcinomas [PTMCs]) and was higher in the ITN-positive group than in the ITN-negative group (3.6% [4/111] vs. 0.6% [14/2,218], P=0.009). Among the 2,011 subjects who underwent both LDCT and thyroid US, all risks were higher (P<0.001) in the ITNpositive group than in the ITN-negative group: presence of thyroid nodule on US, 94.1% (95/101) vs. 48.6% (928/1,910); recommendation of FNA according to the American Thyroid Association guideline and Korean Thyroid Imaging Reporting and Data System guideline, 41.2% (42/101) vs. 2.4% (46/1,910) and 39.6% (40/101) vs. 1.9% (37/1,910), respectively. @*Conclusion@#Despite a higher risk of thyroid cancer in the LDCT ITN-positive group than in the ITN-negative group in a lung cancer screening population, all cancers were PTMCs. A heavy smoking history may not necessitate thorough screening US for thyroid incidentalomas.

Safety of Red Blood Cell Transfusion by the Emergency Blood Transfusion Protocol / 대한수혈학회지

Background@#Pretransfusion testing is vital for safe transfusion. However, in situations without time to perform sufficient testing, all or part of the pretransfusion testing may be skipped to issue blood quickly. This study evaluated the safety of red blood cell (RBC) transfusion released by an emergency blood transfusion protocol through retrospective analysis at a tertiary hospital for eight years. @*Methods@#All RBC transfusions following the emergency blood transfusion protocol from 2011 to 2018 at Seoul National University Hospital were included in the study. Crossmatching and unexpected antibody screening test results conducted after RBC release and the occurrence of hemolytic transfusion reactions were analyzed. @*Results@#A total of 1,541 cases (5,299 RBCs issued) of emergency blood transfusion were identified. RBCs were issued after performing the immediate spin crossmatch without an unexpected antibody screening test in most cases (1,443; 93.64%), while RBCs were issued with no pretransfusion testing in 98 cases (6.36%). Antibody screening tests performed after the issue of RBCs showed that 17 (1.1%) cases were positive. Two units of RBCs from two different cases showed positive antiglobulin crossmatch test results. However, none of them were suspected to be associated with a hemolytic transfusion reaction. @*Conclusion@#The incidence of incompatible RBC release was very low in patients receiving RBC transfusion through the emergency blood transfusion protocol suggesting it can be used safely with minimal risk of hemolytic transfusion reactions caused by incompatible blood transfusions.

Minimum Specimen Volume Analysis of ABO/RhD Typing and Unexpected Antibody Screening Using an Automated Immunohematology System DAYmate S / 대한수혈학회지

BACKGROUND: Phlebotomy performed for laboratory testing has the potential to cause anemia in newborns and infants. This study investigated the minimum specimen volume required for an automated immunohematology analyzer DAYmate S. METHODS: Three combinations of tubes were evaluated: I. 6 mL EDTA tube, II. 0.5 mL microtainer (on top of 3 mL EDTA tube), and III. 1 mL sample cup (on top of 6 mL EDTA tube). ABO/RhD cell typing was done using centrifuged red cells; unexpected antibody screening was carried out using plasma, and Type & Screening was conducted using whole blood samples. The lowest specimen volume capable of performing 10 repetitive tests without errors was investigated. RESULTS: ABO/RhD cell typing could be performed from I. 30 μL, II. 25 μL, and III. 25 μL. Unexpected antibody screening could be performed from I. 170 μL, II. 150 μL, and III. 140 μL. According to the hematocrit levels, Type & Screening could be performed from 30%, I&III 650 μL, II. 800 μL; 40%, I&III 650 μL, II. 900 μL; and 50%, I&III 1,000 μL, II. Testing using specimen volumes below 1,000 μL was difficult. CONCLUSION: By separating red cells and plasma, pre-transfusion testing of ABO/RhD cell typing and unexpected antibody screening could be conducted with very small specimen volumes using DAYmate S compared to Type & Screening using whole blood. The application of small-sized sample tubes was more competitive and this is expected to be very useful for preventing iatrogenic anemia in neonates and infants less than 4 months old.

A Case of Steatocystoma Simplex and Sebaceous Gland Hyperplasia of the Bilateral Lacrimal Caruncle

PURPOSE: A case of bilateral lacrimal caruncle steatocystoma simplex and sebaceous gland hyperplasia, which rarely occurs in the periocular area, is reported. CASE SUMMARY: A 42-year-old female presented with a bilateral caruncular mass, which had been growing for a few months. A physical examination revealed soft, non-tender, rounded masses and no other ophthalmic findings. Under local anesthesia, the masses were completely excised. In the histopathological examination, a cystic mass containing a sebaceous gland in the stratified squamous epithelium cyst wall was found. A hyperplastic sebaceous gland and a dilated sebaceous gland duct were also found. Steatocystoma simplex and sebaceous gland hyperplasia, respectively, were diagnosed. There was no recurrence or complication after excision. CONCLUSIONS: Steatocystoma simplex and sebaceous gland hyperplasia are benign tumors that rarely occur in the lacrimal caruncle. They can be diagnosed and treated by complete excision. Steatocystoma simplex and sebaceous gland hyperplasia should therefore be considered as differential diagnoses of a lacrimal caruncle mass.

A Case of Intractable Vernal Keratoconjunctivitis Treated by Papillectomy and Amniotic Membrane Transplantation

PURPOSE: To report a successful case of intractable vernal keratoconjunctivitis treated by papillectomy and amniotic membrane transplantation. CASE SUMMARY: A 20-year-old female patient presented with repeated vernal keratoconjunctivitis in both eyes since the age of 14. Despite medical therapy, she developed severe itching, burning and foreign body sensations, and limbal nodules with mutiple giant papillae of the upper tarsal plate. Surgical resection of the giant papillae and amniotic membrane transplantation in her left eye was performed. One month later, the same procedure was performed in her right eye. The patient's symptoms then improved. Neither recurrence nor serious complication were observed during the 6 months follow up period after surgery. CONCLUSIONS: In intractable vernal keratoconjunctivitis, papillectomy with amniotic membrane transplantation may potentially be a good treatment option for better clinical outcome and low recurrence rates.

Analysis of the Retinal Nerve Fiber Layer Thickness in Alzheimer Disease and Mild Cognitive Impairment

PURPOSE: To compare the retinal nerve fiber layer (RNFL) as well as the macula volume and thickness in the eyes of age-matched healthy controls with no cognitive disabilities with those of elderly people with mild cognitive impairment (MCI) or Alzheimer disease (AD). We used optical coherence tomography (OCT) to determine the effectiveness of the above quantities for early diagnosis of MCI or AD. METHODS: Ninety eyes were considered in this study, split between 30 normal eyes, 30 eyes from patients with MCI, and 30eyes from patients with AD. All subjects underwent ophthalmologic and cognitive examinations, and measurements of the RNFL thickness as well as macular volume and thickness were taken for all patients using OCT. RESULTS: The mean RNFL thickness upon OCT was significantly thinner in the AD group than in the MCI group (p = 0.01). The RNFL was thinner in the superior quadrant in patients with AD when compared to the healthy controls (p = 0.03). The RNFL thicknesses in the inferior, nasal, and temporal quadrants did not differ significantly between the groups. Measurements in the 12 clock-hour zones revealed that zone 11 had a significantly thinner RNFL in the AD group as compared with the healthy control group (p = 0.02). In zone 2, the MCI group had a significantly thinner RNFL than the AD group (p = 0.03). CONCLUSIONS: Our OCT findings revealed a neuroanatomic difference in the RNFL thickness among the three groups, i.e., the AD, MCI, and healthy control groups. This suggests that a change in average RNFL thickness could be a meaningful index for diagnosing early AD.

Delayed Onset Purtscher's Retinopathy with Serous Retinal Detachment after Trauma in a Retinitis Pigmentosa

PURPOSE: To report a case of Purtscher's retinopathy accompanied by serous retinal detachment in a patient with retinitis pigmentosa (RP) who was referred to us for treatment of post-traumatic visual discomfort. CASE SUMMARY: A 36-year-old man with history of RP was referred to us with the chief complaint of bilateral visual discomfort after chest injury from a traffic accident. His corrected visual acuity was 0.3 and 0.6 in the right and left eyes, respectively. Fundus examination revealed findings characteristic of RP in both eyes, along with a lesion in the right eye, which was suspected to be a serous elevation of the macula, as well as suspected exudates near the optic nerves. Optical coherence tomography indicated serous retinal detachment in the right eye, and fluorescein angiography findings were characteristic of RP. Seven days later, the amount of cotton-wool exudate in the right eye had increased and was more distinct than at the initial examination, and retinal hemorrhage was observed. Based on the medical history and specific fundus findings, the patient was diagnosed with Purtscher's retinopathy. One month later, the serous retinal detachment in the right eye had improved, but the vision loss and total anopsia in the right eye persisted. CONCLUSIONS: The concomitant occurrence of RP and Purtscher's retinopathy is very rare. Moreover, the presence of accompanying serous retinal detachment and delayed onset of typical clinical symptoms are not present in typical Purtscher's retinopathy.

An Unusual Case of Endogenous Klebsiella Pneumonia Endophthalmitis

PURPOSE: To report an unusual case of endogenous endophthalmitis in a patient with Klebsiella pneumoniae primary liver abscess. CASE SUMMARY: A-54-year-old man with diabetes mellitus and liver abscess was referred to us for consultation of visual loss in his left eye for 2 days. On the first examination, the patient's left visual acuity was hand motion and the left intraocular pressure was 13 mmHg. Vitreous opacity and inflammatory membrane were detected with increased echogenicity using ultrasonography. Vitectomy and intravitreous antibiotic injection were performed under the impression of endogenous endophthalmitis caused by liver abscess on the day of the first visit. Culture revealed Klebsiella pneumoniae from blood and liver abscess. After vitrectomy, the patient showed improvement. However, on the 20th and 40th postoperative days, the patient complained of blurred vision, and inflammation and hypopyon were observed in the anterior chamber. An intracameral antibiotic injection and anterior chamber washing were performed. The patient has not complained of any other symptoms to date. CONCLUSIONS: In this patient with endophthalmitis, inflammation and hypopyon in the anterior chamber were evident three times after vitrectomy. Ultimately, the inflammation was effectively controlled by intracameral antibiotic injection and anterior chamber washes.

A Case of Sepsis Caused by Cellulitis in a Patient with Rheumatoid Arthritis after Tocilizumab Treatment

Tocilizumab, a humanized monoclonal antibody against the interleukin-6 receptor, is therapeutically effective in patients diagnosed with rheumatoid arthritis (RA) compared with placebo. However patients treated with tocilizumab are at increased risk of several adverse effects including anaphylaxis and serious infections that may lead to hospitalization or death. Therefore, the risks and benefits of treatment with tocilizumab should be considered carefully and close monitoring of patients for development of signs and symptoms of side effects is required during and after treatment. Here, we report on a rare case of anaphylaxis and severe sepsis caused by cellulitis in a patient with RA after tocilizumab treatment.

Identification of streptococcus dysgalactiae subsp. equisimilis from septic knee by 16S rRNA gene sequencing / 고신대학교의과대학학술지

Septic arthritis is the infection of a joint by an infectious agent, leading to arthritis. It is therefore important to identify and treat the correct bacteria in septic arthritis. However, accurate identification of bacteria by conventional methods is difficult because of the distinct biochemical characteristics of individual bacteria. This case report aims at assessing septic arthritis caused by Streptococcus dysgalactiae subsp. equisimilis(SDSE) using nucleotide sequences and discusses the associated treatment. Here, Streptococcus agalactiae was determined to be the causative bacteria for septic arthritis in a 77 year-old woman using the conventional method of hemolysis pattern interpretation and morphology. However, nucleotide sequence analysis of 16S ribosomal RNA revealed that SDSE was the causative strain. 16S rRNA gene sequencing can correctly identify bacteria strains that are difficult to be identified by traditional method, and this correct identification can provide patients with the opportunity for adequate treatment using the proper antibiotics.

Measurement of Orbital Volume from Different Slice Thickness Facial Computed Tomography Scans Using a Semi-automatic Program

PURPOSE: To compare the orbital volume calculated from various slice thickness facial computed tomography scans using a semi-automated computer program. METHODS: Axial and coronal scans of 2, 2.5, 3 mm slice thickness facial computed tomography scans were used to measure the orbital volume. The cross-sectional area was determined from each slice using a semi-automated computer program (MATLAB 2009a®, MathWorks, Inc., Natick, MA, USA), and then the volume was calculated from serial reconstruction of the cross sections. RESULTS: The measured value in the 2 mm images was 33.14 ± 2.37 cm³ in the right orbit and 34.32 ± 2.60 cm³ in the left orbit for the axial scans, and 35.54 ± 3.58 cm³ in the right orbit and 34.96 ± 4.05 cm³ in the left orbit for the coronal scans. In the 2.5 mm images, the values were 33.28 ± 3.35 cm³ in the right orbit and 33.73 ± 4.10 cm³ in the left orbit for the axial scans, and 35.24 ± 3.98 cm³ in the right orbit and 35.10 ± 3.93 cm³ in the left orbit for the coronal scans. In the 3 mm images, the values were 33.23 ± 2.70 cm³ in the right orbit and 33.39 ± 2.69 cm³ in the left orbit for the axial scans, and 33.20 ± 3.64 cm³ in the right orbit and 32.95 ± 3.45 cm³ in the left orbit for the coronal scans. In the 3 mm image, there was not a significant difference in the calculated volume between the axial and coronal scans (p(3mm) = 0.62). CONCLUSIONS: Because there is no difference in the results of the orbital volumetric measurements between three other slice thicknesses in the axial scan, using axial scan images with a computer program that semi-automatically calculates orbital volume is useful. In addition, the volume measured by thick slice images has more reproducibility than the volume measured by thin slice images.

Comparison between Aflibercept, Ranibizumab Intravitreal Injection on Neovascular Age-related Macular Degeneration Patients

PURPOSE: To investigate the difference of optical coherence tomography (OCT) findings between the aflibercept treatment group and the ranibizumab treatment group. METHODS: This study includes patients diagnosed with treatment-naïve neovascular age-related macular degeneration (AMD), and they were treated with aflibercept (n = 23, 23 eyes) or ranibizumab (n = 26, 26 eyes) monthly for 3 months. In this study, the aflibercept treatment group patients were treated from March 2014 to April 2015, and the ranibizumab treatment group patients were treated from December 2008 to April 2015. After three initial injections, they were followed up monthly for an additional 3 months, and additional treatments were performed if necessary. We compared the changes of the two groups before the treatment and after 6 months of treatment, beginning with the OCT findings, such as serous pigment epithelium detachment, fibrovascular pigment epithelium detachment, subretinal fluid, intraretinal fluid, dense zone of outer retina, classic neovascularization, and hyper- reflective dots. We also compared the changes of best corrected visual acuity (BCVA) and inner segment/outer segment (IS/OS) length, external limiting membrane length, and central foveal thickness with optical OCT between the two groups. RESULTS: In the aflibercept group, 46% of serous epithelial detachments disappeared, while 33% disappeared in the ranibizumab group, and there was significant difference between the two groups (p = 0.01). There was no significant difference in BCVA change or OCT findings between the two groups, but there was a significant difference in serous pigment epithelium detachment. CONCLUSIONS: For treatment of neovascular AMD patients, aflibercept might be more effective in serous pigment epithelium detachment than ranibizumab. Because there was no significant difference in visual acuity improvement in serous pigment detachment for both treatments, it might be necessary to further study the relationship between visual acuity and serous pigment detachment improvement.

A Case of Bilateral Diabetic Papillopathy Related to Rapid Hemoglobin A1c Decrease in Type I Diabetes Mellitus

PURPOSE: To report a case of bilateral diabetic papillopathy related to rapid hemoglobin A1c (HbA1c) decrease in a type I diabetic patient. CASE SUMMARY: A 39-year-old female who was diagnosed with type I diabetes mellitus for the first time at this hospital was presented to our clinic for evaluation of diabetic retinopathy. There were no subjective symptoms, including blurred vision or visual defect. Her best corrected visual acuity in both eyes was 1.0, but her fundus resembled mild nonproliferative diabetic retinopathy. When diagnosed with type I diabetes mellitus, her HbA1c was 15.3%. She used insulin to control her blood glucose and her HbA1c reached 7.3% two months after controlling the blood glucose. Three months after her diabetic diagnosis, there were no differences in subjective symptoms and best corrected visual acuity. Fundus examination showed optic disc swelling in both eyes. To evaluate for the etiology of optic disc swelling, we did the examinations of the optic disc, fundus, and brain magnetic resonance imaging. No specific signs were observed. We diagnosed diabetic papillopathy and observed the patient without any treatments. Her optic disc swelling showed gradual improvement. CONCLUSIONS: This case shows that the rapid HbA1c decrease in type I diabetes mellitus is related to the occurrence of bilateral diabetic papillopathy. This supports previous studies that estimated that the rapid HbA1c decrease in type I diabetes mellitus in response to insulin treatment is one of the risk factors for bilateral diabetic papillopathy.

Bone Flap Resorption Following Cranioplasty after Decompressive Craniectomy: Preliminary Report / 대한신경손상학회지

OBJECTIVE: Resorption of autologous bone flap grafts is a known long-term complication of cranioplasty following decompressive craniectomy (DC). We analyzed our data to identify risk factors for bone flap resorption (BFR) following cranioplasty. METHODS: A total of 162 patients who underwent cranioplasty following DC due to life-threatening elevated intracranial pressure between October 2003 and December 2012, were included in our investigation. Follow-up exceeded one year. RESULTS: BFR occurred as a long-term complication in 9 of the 162 patients (5.6%). The affected patients consisted of individuals who had undergone DC for traumatic brain injury (TBI; n=4), for subarachnoid hemorrhage (SAH; n=3), for cerebral infarction (n=1), and intracerebral hemorrhage (n=1). Logistic regression analysis identified no significant risk factors for BFR. CONCLUSION: TBI and SAH as initial diagnoses are more often associated with BFR than other diagnoses. This finding may influence future surgical decision making, especially in patients with possible risk factors for BFR. A prospective study with a large number of patients is needed to identify potential predictors of BFR such as bone flap sterilization and preservation.

A Case of Eyelid Paraffinoma Misdiagnosed as a Chalazion

PURPOSE: Paraffinoma is a granulomatous reaction to paraffin or oily substances. We report delayed diagnosis of paraffinoma that was misdiagnosed as chalazion. CASE SUMMARY: A 49-year-old male presented with masses, swelling, and erythema in the right lower eyelid, masses and swelling in the right upper eyelid, and intermittent conjunctival injection that had appeared 3 months ago. The patient admitted having received paraffin injection to the right lateral canthal area and nasal bridge for cosmetic purposes by non-medical personnel 17 years prior to presentation. The mass showed partial response to intralesional triamcinolone injection but did not respond to systemic steroid. CONCLUSIONS: Paraffinoma can present diagnostic confusion given its protracted latency period and discordance of injection area and mass location. Detailed history taking is required and the possibility of paraffinoma should be considered for mass lesions of the eyelid.

Amphetamine-Like Weight Reduction Drug Induced Acute Cardiomyopathy with Left Ventricular Thrombosis / 이화의대지

A 37-year-old female patient admitted due to dyspnea on exertion and peripheral edema. For one and a half years, the patient had been taking various drugs and supplements to reduce weight, including amphetamine-like drugs. The patient had no major cardiovascular risk factors except three pack-years of smoking. A chest computed tomography showed a 1.7 cm diameter, capsulated space-occupying lesion in the left ventricle (LV) and 2-dimensional echocardiography showed LV systolic dysfunction (Left ventricular ejection fraction [LVEF], 30%) with a mobile cystic mass (1.1x1.8 cm) that was attached to the LV apex, which was increased in size and number the next day, even with low dose low-molecular-weight heparin. With an increased dose of anticoagulation medication and heart failure management with diuretics and angiotensin receptor II blocker, LV dysfunction was recovered and the LV thrombus disappeared.

Phasic Changes in Bladder Compliance During Filling Cystometry of the Neurogenic Bladder

OBJECTIVE: To investigate phasic changes during filling cystometry that most accurately represent detrusor properties, regardless of other factors affecting detrusor contractility. METHODS: Seventy-eight patients (59 males, 19 females; mean age, 48.2 years) with spinal cord injuries were enrolled. Urodynamic studies were performed using a normal saline filling rate of 24 mL/min. We calculated bladder compliance values of the detrusor muscle in each of three filling phase intervals, which divided the filling cystometrogram into three phases referable to the cystometric capacity or maximum cystometric capacity. The three phases were sequentially delineated by reference to the pressure-volume curve reflecting bladder filling. RESULTS: Bladder compliance during the first and second phases of filling cystometry was significantly correlated with overall bladder compliance in overactive detrusors. The highest coefficient of determination (r2=0.329) was obtained during the first phase of the pressure-volume curve. Bladder compliance during all three phases was significantly correlated with overall bladder compliance of filling cystometry in underactive detrusors. However, the coefficient of determination was greatest (r2=0.529) during the first phase of filling cystometry. CONCLUSION: Phasic bladder compliance during the early filling phase (first filling phase) was the most representative assessment of overall bladder compliance during filling cystometry. Careful determination of early phase filling is important when seeking to acquire reliable urodynamic data on neurogenic bladders.

Success Rate of Silicone Intubation Between Nasolacrimal Duct Obstruction and Stenosis According to Dacryocystography

PURPOSE: This study compares the success rate of silicone tube intubation between nasolacrimal duct obstruction and stenosis according to dacryocystographic findings. METHODS: A total of 115 patients who suffered from epiphora were divided into nasolacrimal duct obstruction and nasolacrimal duct stenosis according to dacryocystographic findings. Silicone tube intubation was performed on every patient. The success rate was estimated based on functional and anatomical success. Functional success was estimated by patient's satisfaction with 'good' or 'fair' at the last visit, and anatomical success was estimated by decrease or normalization of tear meniscus height. Surgery success was defined when anatomical and functional successes were fulfilled. RESULTS: Success rate of silicone tube intubation was 75.76% for patients with nasolacrimal duct obstruction based on dacryocystography, and 86.59% for patients with nasolacrimal duct stenosis based on dacryocystography; the difference was not statistically significant (Pearson chi-square test, p = 0.693). CONCLUSIONS: Silicone tube intubation can be considered as a primary treatment option for management of epiphora in nasolacrimal duct stenosis and obstruction.

Emphysematous Pyelonephritis Caused by Citrobacter freundii in a Patient with Type 2 Diabetes and Neurogenic Bladder / 감염과화학요법

Emphysematous pyelonephritis (EPN) is a rare, life-threatening complication of upper urinary tract infections that is characterized by the presence of gas in the renal parenchyma and perirenal space. It commonly occurs in diabetic patients. Escherichia coli are the most common causative organisms, with few reports implicating Citrobacter freundii as the etiologic agent in EPN. A 57-year-old woman with diabetes and neurogenic bladder visited at our department with confused mentality, myalgia, and general weakness. Further investigation revealed that the patient suffered from unilateral EPN with sepsis caused by C. freundii. The patient's condition was improved considerably with percutaneous drainage and use of intravenous antibiotics for several weeks. However, renal function eventually deteriorated to permanent renal failure, which required hemodialysis. In conclusion, C. freundii may be the causative pathogen of EPN in a patient with type 2 diabetes and neurogenic bladder.

Clinical Experiences of Unruptured Vertebral Artery Dissection / 대한신경손상학회지

OBJECTIVE: The natural course of unruptured vertebral artery dissection remains unclear. The clinical manifestation of unruptured vertebral artery dissection varies from headache, focal neurologic deficits caused by ischemia to subarachnoid hemorrhage with high mortality. The purpose of this study is to investigate the clinical course of unruptured vertebral artery dissection. METHODS: From March 2011 to April 2013, 7 patients with headache or nuchal pain by spontaneous vertebral artery dissection visited our institute were retrospectively reviewed. Their clinical data was obtained by medical records and radiologic studies including computed tomographic angiography, magnetic resonance imaging, magnetic resonance angiography and digital subtraction angiography. RESULTS: No patient experienced fatal outcome by subarachnoid hemorrhage or vertebrobasilar ischemia during follow-up period. Radiologic studies also did not show the evidence of subarachnoid hemorrhage or vertebrobasilar ischemia. Follow-up angiography showed the decreased size or disappearance of aneurysm in 3 patients. CONCLUSION: This study suggests that the natural course of unruptured vertebral artery dissection is not aggressive. Patients with unruptured vertebral artery dissection could be managed with conservative treatment including anticoagulants and/or antiplatelet agents.