Characteristics of Focused Ultrasound Mediated Blood-Brain Barrier Opening in Magnetic Resonance Images

Objective@#: The blood-brain barrier (BBB) is an obstacle for molecules to pass through from blood to the brain. Focused ultrasound is a new method which temporarily opens the BBB, which makes pharmaceutical delivery or removal of neurodegenerative proteins possible. This study was demonstrated to review our BBB opening procedure with magnetic resonance guided images and find specific patterns in the BBB opening. @*Methods@#: In this study, we reviewed the procedures and results of two clinical studies on BBB opening using focused ultrasound regarding its safety and clinical efficacy. Magnetic resonance images were also reviewed to discover any specific findings. @*Results@#: Two clinical trials showed clinical benefits. All clinical trials demonstrated safe BBB opening, with no specific side effects. Magnetic resonance imaging showed temporary T1 contrast enhancement in the sonication area, verifying the BBB opening. Several low-signal intensity spots were observed in the T2 susceptibility-weighted angiography images, which were also reversible and temporary. Although these spots can be considered as microbleeding, evidence suggests these are not ordinary microbleeding but an indicator for adequate BBB opening. @*Conclusion@#: Magnetic resonance images proved safe and efficient BBB opening in humans, using focused ultrasound.

Simulation Method for the Physical Deformation of a Three-Dimensional Soft Body in Augmented Reality-Based External Ventricular Drainage / 대한의료정보학회지

Objectives@#Intraoperative navigation reduces the risk of major complications and increases the likelihood of optimal surgical outcomes. This paper presents an augmented reality (AR)-based simulation technique for ventriculostomy that visualizes brain deformations caused by the movements of a surgical instrument in a three-dimensional brain model. This is achieved by utilizing a position-based dynamics (PBD) physical deformation method on a preoperative brain image. @*Methods@#An infrared camera-based AR surgical environment aligns the real-world space with a virtual space and tracks the surgical instruments. For a realistic representation and reduced simulation computation load, a hybrid geometric model is employed, which combines a high-resolution mesh model and a multiresolution tetrahedron model. Collision handling is executed when a collision between the brain and surgical instrument is detected. Constraints are used to preserve the properties of the soft body and ensure stable deformation. @*Results@#The experiment was conducted once in a phantom environment and once in an actual surgical environment. The tasks of inserting the surgical instrument into the ventricle using only the navigation information presented through the smart glasses and verifying the drainage of cerebrospinal fluid were evaluated. These tasks were successfully completed, as indicated by the drainage, and the deformation simulation speed averaged 18.78 fps. @*Conclusions@#This experiment confirmed that the AR-based method for external ventricular drain surgery was beneficial to clinicians.

Dual Pallidal and Thalamic Deep Brain Stimulation for Complex Ipsilateral Dystonia

Purpose@#Globus pallidus pars interna (GPi) has become an established target for deep brain stimulation (DBS) in dystonia. Previous studies suggest that targeting the ventralis oralis (Vo) complex nucleus improves dystonic tremor or even focal dystonia. Research has also demonstrated that multi-target DBS shows some benefits over single target DBS. In this study, we reviewed patients who had undergone unilateral DBS targeting the GPi and Vo. @*Materials and Methods@#Five patients diagnosed with medically refractory upper extremity dystonia (focal or segmental) underwent DBS. Two DBS electrodes each were inserted unilaterally targeting the ipsilateral GPi and Vo. Clinical outcomes were evaluated using the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) and Disability Rating Scale. @*Results@#BFMDRS scores decreased by 55% at 1-month, 56% at 3-month, 59% at 6-month, and 64% at 12-month follow up. Disability Rating Scale scores decreased 41% at 1-month, 47% at 3-month, 50% at 6-month, and 60% at 12-month follow up. At 1 month after surgery, stimulating both targets improved clinical scores better than targeting GPi or Vo alone. @*Conclusion@#Unilateral thalamic and pallidal dual electrode DBS may be as effective or even superior to DBS of a single target for dystonia. Although the number of patients was small, our results reflected favorable clinical outcomes.

Temporal Volume Change of Cavernous Sinus Cavernous Hemangiomas after Gamma Knife Surgery

Cavernous hemangiomas occur very rarely in the cavernous sinus. This study aimed to evaluate the efficacy of Gamma Knife surgery (GKS) on cavernous sinus cavernous hemangioma (CSCH) and to analyze the temporal volume change. We retrospectively reviewed the clinical data of 26 CSCH patients who were treated with GKS between 2001 and 2017. Before GKS, 11 patients (42.3%) had cranial neuropathies and 5 patients (19.2%) complained of headache, whereas 10 patients (38.5%) were initially asymptomatic. The mean pre-GKS mass volume was 9.3 mL (range, 0.5–31.6 mL), and the margin dose ranged from 13 to 15 Gy according to the mass volume and the proximity to the optic pathway. All cranial neuropathy patients and half of headache patients showed clinical improvement. All 26 patients achieved mass control; remarkable responses (less than 1/3 of the initial mass volume) were shown in 19 patients (73.1%) and moderate responses (more than 1/3 and less than 2/3) in 7 patients (26.9%). The mean final mass volume after GKS was 1.8 mL (range, 0–12.6 mL). The mean mass volume at 6 months after GKS was 45% (range, 5–80%) compared to the mass volume before GKS and 21% (range, 0–70%) at 12 months. The higher radiation dose tended to induce more rapid and greater volume reduction. No treatment-related complication was observed during the follow-up period.GKS could be an effective and safe therapeutic strategy for CSCH. GKS induced very rapid volume reduction compared to other benign brain tumors.

Comparison of Clinical Characteristics in Vogt-Koyanagi-Harada Disease between Patients with and without Prodromal Manifestations

Purpose@#To compare the clinical characteristics of Vogt-Koyanagi-Harada (VKH) disease between patients with and without prodromal manifestations. @*Methods@#We retrospectively reviewed the medical records of patients with VKH disease who were treated with systemic steroids. We grouped the patients into the incomplete type (36 eyes of 18 patients) and probable type (32 eyes of 16 patients) according to the presence of prodromal manifestations. We compared the following outcomes between groups: best-corrected visual acuity (BCVA), anterior chamber (A/C) cell, central foveal thickness (CFT), maximal subretinal fluid (SRF) height, choroidal thickness at baseline and 12 months after treatment, and recurrence rate. @*Results@#BCVA logarithm of the minimum angle of resolution (logMAR) significantly improved from 0.37 ± 0.26 at baseline to 0.09 ± 0.17 at 12 months in the incomplete type group (p < 0.05) and from 0.35 ± 0.24 at baseline to 0.10 ± 0.18 at 12 months in the probable type group (p < 0.05); BCVA did not significantly differ between groups. Choroidal thickness significantly decreased at 12 months after treatment, compared with one week after treatment, in both groups (p < 0.05); choroidal thickness did not significantly differ between groups. There were no significant differences in clinical factors between groups, including baseline A/C cell, CFT, maximal SRF height, and recurrence rate. @*Conclusions@#No associations were found between disease type and clinical outcomes (BCVA, OCT findings, and recurrence). These data suggested that categorization of disease according to prodromal manifestations has limited usefulness in terms of clinical outcomes of VKH disease.

Short-term Clinical Outcomes of Scleral Fixation of Intraocular Lenses Using a Scleral Tunnel and Groove

PURPOSE: We evaluated the short-term clinical outcomes of patients who underwent modified scleral fixation of an intraocular lens (IOL) using a scleral tunnel and groove. METHODS: From June 2016 to May 2017, 34 eyes of 34 patients who underwent modified scleral fixation of an IOL using a scleral tunnel and groove were retrospectively studied. We evaluated the best-corrected visual acuity (BCVA), corneal endothelial cell density, intraocular pressure (IOP), spherical equivalent, and postoperative complications at 1 week, 1 month, 3 months, and 6 months after surgery. RESULTS: The BCVA was 0.85 ± 0.83 logarithm of the minimal angle of resolution (logMAR) before surgery and 0.38 ± 0.61 logMAR at 6 months (p = 0.001). The corneal endothelial cell count was 1,955.12 ± 217/mm2 and 1,852.59 ± 190/mm2, before and after surgery, respectively, which was not significantly different (p = 0.186). Postoperative complications occurred in eight eyes (23.5%); IOP elevation in one eye (2.9%), IOL tilt or decentration in two eyes (5.7%), optic capture in four eyes (11.4%), and cystic macular edema in one eye (2.9%). The spherical equivalent showed myopic changes after surgery and decreased significantly over time (p = 0.001). CONCLUSIONS: Modified scleral fixation of the IOL using a scleral tunnel and groove improved the BCVA, but did not significantly affect corneal endothelial cell loss. This procedure can be a good alternative to conventional scleral fixation of an IOL, which has advantages in shortened surgical time and easy surgical manipulation.

The Potential Usefulness of Magnetic Resonance Guided Focused Ultrasound for Obsessive Compulsive Disorders

Obsessive compulsive disorder is a debilitating condition characterized by recurrent obsessive thoughts and compulsive reactions. A great portion of the obsessive compulsive disorder (OCD) patients are managed successfully with psychiatric treatment such as selective serotonin-reuptake inhibitor and cognitive behavioral psychotherapy, but more than 10% of patients are remained as non-responder who needs neurosurgical treatments. These patients are potential candidates for the neurosurgical management. There had been various kind of operation, lesioning such as leucotomy or cingulotomy or capsulotomy or limbic leucotomy, and with advent of stereotaxic approach and technical advances, deep brain stimulation was more chosen by neurosurgeon due to its characteristic of reversibility and adjustability. Gamma knife radiosurgery are also applied to make lesion targeting based on magnetic resonance (MR) imaging, but the complication of adverse radiation effect is not predictable. In the neurosurgical field, MR guided focused ultrasound has advantage of less invasiveness, real-time monitored procedure which is now growing to attempt to apply for various brain disorder. In this review, the neurosurgical treatment modalities for the treatment of OCD will be briefly reviewed and the current state of MR guided focused ultrasound for OCD will be suggested.

The Potential Usefulness of Magnetic Resonance Guided Focused Ultrasound for Obsessive Compulsive Disorders

Obsessive compulsive disorder is a debilitating condition characterized by recurrent obsessive thoughts and compulsive reactions. A great portion of the obsessive compulsive disorder (OCD) patients are managed successfully with psychiatric treatment such as selective serotonin-reuptake inhibitor and cognitive behavioral psychotherapy, but more than 10% of patients are remained as non-responder who needs neurosurgical treatments. These patients are potential candidates for the neurosurgical management. There had been various kind of operation, lesioning such as leucotomy or cingulotomy or capsulotomy or limbic leucotomy, and with advent of stereotaxic approach and technical advances, deep brain stimulation was more chosen by neurosurgeon due to its characteristic of reversibility and adjustability. Gamma knife radiosurgery are also applied to make lesion targeting based on magnetic resonance (MR) imaging, but the complication of adverse radiation effect is not predictable. In the neurosurgical field, MR guided focused ultrasound has advantage of less invasiveness, real-time monitored procedure which is now growing to attempt to apply for various brain disorder. In this review, the neurosurgical treatment modalities for the treatment of OCD will be briefly reviewed and the current state of MR guided focused ultrasound for OCD will be suggested.

Factors associated with hospitalization via emergency department in children with acute bronchiolitis

PURPOSE: In infants and young children, acute bronchiolitis is a leading cause of hospitalization via emergency departments (EDs). We aimed to investigate factors associated with hospitalization via ED in children with acute bronchiolitis. METHODS: We reviewed medical records of children aged 36 months or younger with acute bronchiolitis who visited the ED from January to December 2017. The following clinical data were collected and analyzed: age, sex, premature birth history, symptoms, fever duration, presence of respiratory distress and radiographic lesion, and inflammatory markers. RESULTS: Of 780 children enrolled, 463 (59.4%) were hospitalized via the ED. The factor associated with the hospitalization were age ≤ 12 months (odd ratio [OR], 45.34; confidence interval [CI], 17.50-117.44), fever lasting ≥ 3 days (OR, 13.66; 95% CI, 6.46-28.87), respiratory rate ≥ 24 breaths per minute (OR, 6.88; 95% CI, 4.21-11.26), radiographic lesion (OR, 5.70; 95% CI, 2.62-12.40), and chest retraction (OR, 2.45; 95% CI, 1.11-5.41). CONCLUSION: In children with acute bronchiolitis who visit EDs, those having younger age, longer fever duration, respiratory distress or radiographic lesion may need hospitalization.

Optimal Treatment Decision for Brain Metastases of Unknown Primary Origin: The Role and Timing of Radiosurgery

BACKGROUND: Up to 15% of all patients with brain metastases have no clearly detected primary site despite intensive evaluation, and this incidence has decreased with the use of improved imaging technology. Radiosurgery has been evaluated as one of the treatment modality for patients with limited brain metastases. In this study, we evaluated the effectiveness of radiosurgery for brain metastases from unknown primary tumors. METHODS: We retrospectively evaluated 540 patients who underwent gamma knife radiosurgery (GKRS) for brain metastases radiologically diagnosed between August 1992 and September 2007 in our institution. First, the brain metastases were grouped into metachronous, synchronous, and precocious presentations according to the timing of diagnosis of the brain metastases. Then, synchronous and precocious brain metastases were further grouped into 1) unknown primary; 2) delayed known primary; and 3) synchronous metastases according to the timing of diagnosis of the primary origin. We analyzed the survival time and time to new brain metastasis in each group. RESULTS: Of the 540 patients, 29 (5.4%) presented precocious or synchronous metastases (34 GKRS procedures for 174 lesions). The primary tumor was not found even after intensive and repeated systemic evaluation in 10 patients (unknown primary, 34.5%); found after 8 months in 3 patients (delayed known primary, 1.2%); and diagnosed at the same time as the brain metastases in 16 patients (synchronous metastasis, 55.2%). No statistically significant differences in survival time and time to new brain metastasis were found among the three groups. CONCLUSION: Identification of a primary tumor before GKRS did not affect the patient outcomes. If other possible differential diagnoses were completely excluded, early GKRS can be an effective treatment option for brain metastases from unknown primary tumor.

Long-Term Outcome of Treatment with Topical Corticosteroids for Severe Dry Eye Associated with Sjogren's Syndrome / 전남의대학술지

This retrospective study was performed to analyze the long-term outcome of topical corticosteroid treatment for severe dry eye associated with Sjogren's syndrome (SS). Patients who had severe dry eye associated with SS were topically treated with loteprednol etabonate 0.5% (group A, n=66) or fluorometholone 0.1% (group B, n=67) twice daily and were followed up for 2 years. Visual acuity (VA), intraocular pressure (IOP), Schirmer test, tear film breakup time (BUT), keratoepitheliopathy, and symptom scores were measured at baseline and 6, 12, 18, and 24 months after treatment. VA and IOP were not changed significantly during follow-up in either group. Schirmer test results, keratoepitheliopathy, and symptom scores at 6, 12, 18, and 24 months (p<0.05) and tear film BUT at 12, 18, and 24 months (p<0.05) significantly improved after treatment compared with baseline in both groups. No significant differences between the groups were found in any parameter during follow-up. At 24 months, the number of patients with IOP elevation of more than 2 mmHg compared with baseline was 4 in group A (6.1%) and 9 in group B (13.4%). The mean IOP in these patients was lower in group A than in group B (15.00+/-0.82 mmHg versus 16.50+/-1.12 mmHg; p=0.04). Long-term application of low-dose topical corticosteroids is effective for controlling signs and symptoms of chronic, severe dry eye associated with SS. Loteprednol etabonate 0.5% may have a lower risk for IOP elevation than fluorometholone 0.1%.

Effect of Subthalamic Deep Brain Stimulation on Levodopa-Induced Dyskinesia in Parkinson's Disease

PURPOSE: To evaluate the effect of bilateral subthalamic nucleus (STN) deep brain stimulation (DBS) on levodopa-induced peakdose dyskinesia in patients with Parkinson's disease (PD). MATERIALS AND METHODS: A retrospective review was conducted on patients who underwent STN DBS for PD from May 2000 to July 2012. Only patients with levodopa-induced dyskinesia prior to surgery and more than 1 year of available follow-up data after DBS were included. The outcome measures included the dyskinesia subscore of the Unified Parkinson's Disease Rating Scale (UPDRS) part IV (items 32 to 34 of UPDRS part IV) and the levodopa equivalent daily dose (LEDD). The patients were divided into two groups based on preoperative to postoperative LEDD change at 12 months after the surgery: Group 1, LEDD decrease >15%; Group 2, all other patients. Group 2 was further divided by the location of DBS leads. RESULTS: Of the 100 patients enrolled, 67 were in Group 1, while those remaining were in Group 2. Twelve months after STN DBS, Groups 1 and 2 showed improvements of 61.90% and 57.14%, respectively, in the dyskinesia subscore. Group 1 was more likely to experience dyskinesia suppression; however, the association between the groups and dyskinesia suppression was not statistically significant (p=0.619). In Group 2, dyskinesia was significantly decreased by stimulation of the area above the STN in 18 patients compared to stimulation of the STN in 15 patients (p=0.048). CONCLUSION: Levodopa-induced dyskinesia is attenuated by STN DBS without reducing the levodopa dosage.

The Neuromodulation of Neuropathic Pain by Measuring Pain Response Rate and Pain Response Duration in Animal

OBJECTIVE: Neuropathic pain causes patients feel indescribable pain. Deep Brain Stimulation (DBS) is one of the treatment methods in neuropathic pain but the action mechanism is still unclear. To study the effect and mechanism of analgesic effects from DBS in neuropathic pain and to enhance the analgesic effect of DBS, we stimulated the ventral posterolateral nucleus (VPL) in rats. METHODS: To observe the effect from VPL stimulation, we established 3 groups : normal group (Normal group), neuropathic pain group (Pain group) and neuropathic pain+DBS group (DBS group). Rats in DBS group subjected to electrical stimulation and the target is VPL. RESULTS: We observed the behavioral changes by DBS in VPL (VPL-DBS) on neuropathic pain rats. In our study, the pain score which is by conventional test method was effectively decreased. In specific, the time of showing withdrawal response from painful stimulation which is not used measuring method in our animal model was also decreased by DBS. CONCLUSION: The VPL is an effective target on pain modulation. Specifically we could demonstrate changes of pain response duration which is not used, and it was also significantly meaningful. We thought that this study would be helpful in understanding the relation between VPL-DBS and neuropathic pain.

Long-Term Outcome of Treatment with Topical Corticosteroids for Severe Dry Eye Associated with Sjogren's Syndrome / 전남의대학술지

This retrospective study was performed to analyze the long-term outcome of topical corticosteroid treatment for severe dry eye associated with Sjogren's syndrome (SS). Patients who had severe dry eye associated with SS were topically treated with loteprednol etabonate 0.5% (group A, n=66) or fluorometholone 0.1% (group B, n=67) twice daily and were followed up for 2 years. Visual acuity (VA), intraocular pressure (IOP), Schirmer test, tear film breakup time (BUT), keratoepitheliopathy, and symptom scores were measured at baseline and 6, 12, 18, and 24 months after treatment. VA and IOP were not changed significantly during follow-up in either group. Schirmer test results, keratoepitheliopathy, and symptom scores at 6, 12, 18, and 24 months (p<0.05) and tear film BUT at 12, 18, and 24 months (p<0.05) significantly improved after treatment compared with baseline in both groups. No significant differences between the groups were found in any parameter during follow-up. At 24 months, the number of patients with IOP elevation of more than 2 mmHg compared with baseline was 4 in group A (6.1%) and 9 in group B (13.4%). The mean IOP in these patients was lower in group A than in group B (15.00+/-0.82 mmHg versus 16.50+/-1.12 mmHg; p=0.04). Long-term application of low-dose topical corticosteroids is effective for controlling signs and symptoms of chronic, severe dry eye associated with SS. Loteprednol etabonate 0.5% may have a lower risk for IOP elevation than fluorometholone 0.1%.

Long-Term Outcome of Treatment with Topical Corticosteroids for Severe Dry Eye Associated with Sjogren's Syndrome / 전남의대학술지

This retrospective study was performed to analyze the long-term outcome of topical corticosteroid treatment for severe dry eye associated with Sjogren's syndrome (SS). Patients who had severe dry eye associated with SS were topically treated with loteprednol etabonate 0.5% (group A, n=66) or fluorometholone 0.1% (group B, n=67) twice daily and were followed up for 2 years. Visual acuity (VA), intraocular pressure (IOP), Schirmer test, tear film breakup time (BUT), keratoepitheliopathy, and symptom scores were measured at baseline and 6, 12, 18, and 24 months after treatment. VA and IOP were not changed significantly during follow-up in either group. Schirmer test results, keratoepitheliopathy, and symptom scores at 6, 12, 18, and 24 months (p<0.05) and tear film BUT at 12, 18, and 24 months (p<0.05) significantly improved after treatment compared with baseline in both groups. No significant differences between the groups were found in any parameter during follow-up. At 24 months, the number of patients with IOP elevation of more than 2 mmHg compared with baseline was 4 in group A (6.1%) and 9 in group B (13.4%). The mean IOP in these patients was lower in group A than in group B (15.00+/-0.82 mmHg versus 16.50+/-1.12 mmHg; p=0.04). Long-term application of low-dose topical corticosteroids is effective for controlling signs and symptoms of chronic, severe dry eye associated with SS. Loteprednol etabonate 0.5% may have a lower risk for IOP elevation than fluorometholone 0.1%.

Long-Term Results of Gamma Knife Radiosurgery for Intracranial Meningioma

BACKGROUND: The predominant treatment modality for meningioma is surgical resection. However, gamma knife radiosurgery is also an important treatment modality for meningioma that is small or cannot be completely removed because of its location. In this study, we evaluated the effectiveness and long-term results of radiosurgical treatment for meningioma in our institution. METHODS: We studied 628 patients (130 men and 498 women) who underwent gamma knife radiosurgery for intracranial meningioma, which is radiologically diagnosed, from Jan 2008 to Nov 2012. We included patients with single lesion meningioma, and followed up after 6 months with imaging, and then at 24 months with a clinical examination. Patients with high-grade meningioma or multiple meningiomas were excluded. We analyzed each of the factors associated with progression free survival. The median patient's age was 56.8 years. Maximal dosage was 27.8 Gy and marginal dosage was 13.9 Gy. RESULTS: The overall tumor control rate was 95%. Twenty-eight patients (4.4%) showed evidence of tumor recurrence. Ninety-eight patients (15%) developed peritumoral edema (PTE) after gamma-knife surgery; two of them (2%) underwent surgical resections due to PTE. Nine patients had craniotomy and tumor removal after gamma knife surgery. CONCLUSION: Gamma knife surgery for intracranial meningioma has proven to be a safe and effective treatment tool with successful long-term outcomes. Gamma knife radiosurgery can be especially effective in cases of remnant meningioma after surgical resection or where PTE is not present.

Clinical Efficacy of Topical 3% Diquafosol Tetrasodium in Short Tear Film Break-Up Time Dry Eye

PURPOSE: To evaluate the clinical efficacy of topical diquafosol tetrasodium 3% ophthalmic solution in patients with short tear film break-up time (BUT) dry eye. METHODS: This prospective study involved 30 eyes in 30 patients with dry eye who had tear film BUT values or =5 mm, and showed no improvement with non-preservative sodium hyaluronate (SH) 0.1% artificial tears. All patients were treated with topical diquafosol tetrasodium 3% 6 times a day, in addition to SH 0.1% artificial tears. Schirmer's 1 test, tear film BUT, keratoepitheliopathy score with fluorescein, conjunctival staining score with lissamine green, and Ocular surface disease index (OSDI) score were evaluated at before treatments, and 1 month and 3 months after treatments. RESULTS: Significant improvements of tear film BUT and OSDI were observed at 1 month and 3 months after diquafosol tetrasodium 3% administration. At before treatment, and followed up at 1 and 3 months, tear film BUTs were 3.3 +/- 1.2, 4.4 +/- 1.0 (p < 0.01) and 4.9 +/- 1.1 seconds (p < 0.01), respectively, and OSDI scores were 43.5 +/- 24.4, 34.6 +/- 25.0 (p = 0.01) and 26.7 +/- 21.5 (p < 0.01), respectively. There were no significant changes of Schirmer's score, keratoepitheliopathy, and conjunctival staining score. After diquafosol tetrasodium 3% administration, severe adverse effects were not found in any of the patients. CONCLUSIONS: Topical diquafosol tetrasodium 3% administration was shown to be an effective treatment for improvements of tear film stability and dry eye symptoms.

Comparison of Portable Tonometers and Goldmann Applanation Tonometer for Intraocular Pressure Measurement

PURPOSE: To compare the intraocular pressure (IOP) measured by portable rebound tonometer and TonoPen applanation tonometer with pressure measured by Goldmann applanation tonometer (GAT) and analyze the factors affecting IOP disagreement between tonometers. METHODS: In a prospective study of 463 eyes, IOP was measured with Icare Pro(R) rebound tonometer, TonoPen AVIA(R) applanation tonometer, and GAT. Bland-Altman plot, intraclass correlation coefficient, Pearson's correlation analysis, and multiple regression analysis were performed to evaluate the agreement of IOP measured by each tonometer and the factors affecting the measurements. RESULTS: The IOP values measured by Icare Pro(R) and TonoPen AVIA(R) were consistently higher than those measured by GAT, but showed no significant differences with those measured by GAT (p = 0.307 and 0.114, respectively). In Bland-Altman plot, the IOP values measured by Icare Pro(R) and TonoPen AVIA(R) exhibited excellent agreement with those measured by GAT. Both Icare Pro(R)/GAT and TonoPen AVIA(R)/GAT differences increased with younger age (p = 0.041 and 0.049, respectively) and higher central corneal thickness (p = 0.019 and 0.035, respectively). CONCLUSIONS: IOPs measured by portable Icare Pro(R) rebound tonometer and TonoPen AVIA(R) applanation tonometer were significantly correlated with IOP measured by GAT. Therefore, such instruments can be useful when measuring IOP with GAT is difficult. However, central corneal thickness and age should be considered when measuring IOP with portable tonometers.

Delayed Dural Arteriovenous Fistula after Microvascular Decompression for Hemifacial Spasm

Dural arteriovenous fistula (AVF) is very rare, acquired lesion that may present with intracranial hemorrhage or neurological deficits. The etiology is not completely understood but dural AVF often has been associated with thrombosis of the involved dural sinuses. To our knowledge, this is the first well documented intracranial hemorrhage case caused by dural AVF following microvascular decompression for hemifacial spasm. A 49-year-old male patient had left microvascular decompression of anterior inferior cerebellar artery via retrosigmoid suboccipital craniotomy. The patient was in good condition without any residual spasm or surgery-related complications. However, after 10 months, he suffered sudden onset of amnesia and dysarthria. Computed tomography and magnetic resonance imaging revealed the presence of dural AVF around the left transverse-sigmoid sinus. The dural AVF was treated with Onyx(R) (ev3) embolization. At the one-year follow up visit, there were no evidence of recurrence and morbidity related to dural AVF and its treatment. This case confirms that the acquired etiology of dural AVF may be associated with retrosigmoid suboccipital craniotomy for hemifacial spasm, even though it is an extremely consequence of this procedure.

Which Emphasizing Factors Are Most Predictive of Hematoma Expansion in Spot Sign Positive Intracerebral Hemorrhage?

OBJECTIVE: The spot sign is related with the risk of hematoma expansion in spontaneous intracerebral hemorrhage (ICH). However, not all spot sign positive patients undergo hematoma expansion. Thus, the present study investigates the specific factors enhancing the spot sign positivity in predicting hematoma expansion. METHODS: We retrospectively studied 316 consecutive patients who presented between March 2009 to March 2011 with primary ICH and whose initial computed tomography brain angiography (CTA) was performed at our Emergency Department. Of these patients, 47 primary ICH patients presented spot signs in their CTA. We classified these 47 patients into two groups based on the presence of hematoma expansion then analyzed them with the following factors : gender, age, initial systolic blood pressure, history of anti-platelet therapy, volume and location of hematoma, time interval from symptom onset to initial CTA, spot sign number, axial dimension, and Hounsfield Unit (HU) of spot signs. RESULTS: Of the 47 spot sign positive patients, hematoma expansion occurred in 26 patients (55.3%) while the remaining 21 (44.7%) showed no expansion. The time intervals from symptom onset to initial CTA were 2.42+/-1.24 hours and 3.69+/-2.57 hours for expansion and no expansion, respectively (p=0.031). The HU of spot signs were 192.12+/-45.97 and 151.10+/-25.14 for expansion and no expansion, respectively (p=0.001). CONCLUSIONS: The conditions of shorter time from symptom onset to initial CTA and higher HU of spot signs are the emphasizing factors for predicting hematoma expansion in spot sign positive patients.