Yoon Ho Lee

Bio: Yoon Ho Lee is an academic researcher from Boston Children's Hospital. The author has contributed to research in topics: Arachnoid cyst & Standard treatment. The author has an hindex of 2, co-authored 2 publications receiving 104 citations.

Treatment option for arachnoid cysts

Abstract: Objective The objective of this study is to establish which treatment is the best operative intervention for arachnoid cyst.

Treatment strategy for intracranial primary pure germinoma

Abstract: This prospective randomized clinical study will address the efficacy of radiation (RT)-alone and combined with pre-RT chemotherapy (CTX) treatments and propose the novel standard treatment strategy for intracranial primary pure germinoma. Between 2005 and 2008, there were 54 patients diagnosed with intracranial primary pure germinomas in a single institute. Twenty-eight patients were enrolled. The mean age of the patients was 16.2 years (range 6–31 years). There were 19 men and 9 women (men/women ratio = 2.1:1). There were 21 patients with solitary tumors and 7 with multiple tumors. These patients were randomized as RT-only treatment group (11 solitary and 3 multiple tumors) and combined (10 solitary and 4 multiple tumors, neo-adjuvant CTX followed by response-adapted RT) treatment group. The follow-up period for RT only group has a median of 58 months (mean 58.2 months, range 41–82 months), and for combine therapy group, the median was 68.5 months (mean 67.8 months, range 41–88 months). All 14 patients in the RT-only group showed complete response (CR) and no recurrence. Eleven patients in the combined group had CR and three patients had partial response after neo-adjuvant CTX. All patients responded to RT as CR without recurrence. At the time of analysis, all 28 patients were alive without evidence of disease. Neo-adjuvant CTX for localized germinomas seems to be unnecessary as a method to reduce radiation dose in our RT protocol. However, the effective control of multifocal or disseminated germinoma can be achieved by neo-adjuvant CTX followed by response-adapted reduced dose RT.

Prevalence and natural history of arachnoid cysts in children.

Abstract: Object Arachnoid cysts are a frequent finding on intracranial imaging in children. The prevalence and natural history of these cysts are not well defined. The authors studied a large consecutive series of children undergoing MR imaging to better define both the MR imaging–demonstrated prevalence and behavior of these lesions over time. Methods The authors reviewed a consecutive series of 11,738 patients who were 18 years of age or younger and had undergone brain MR imaging at a single institution during an 11-year period. In the patients in whom intracranial arachnoid cysts were identified, clinical and demographic information was recorded and imaging characteristics, such as cyst size and location, were evaluated. Prevalence data were analyzed using univariate and multivariate logistic regression, linear regression, and ANOVA. All patients with sufficient data (repeat MR imaging studies as well as repeated clinical evaluation over at least 5 months) for a natural history analysis were identified. This gr...

Prevalence and natural history of arachnoid cysts in adults.

Abstract: Object Arachnoid cysts are a frequent finding on intracranial imaging. The prevalence and natural history of these cysts in adults are not well defined. Methods We retrospectively reviewed the electronic medical records of a consecutive series of adults who underwent brain MRI over a 12-year interval to identify those with arachnoid cysts. The MRI studies were reviewed to confirm the diagnosis. For those patients with arachnoid cysts, we evaluated presenting symptoms, cyst size, and cyst location. Patients with more than 6 months' clinical and imaging follow-up were included in a natural history analysis. Results A total of 48,417 patients underwent brain MRI over the study period. Arachnoid cysts were identified in 661 patients (1.4%). Men had a higher prevalence than women (p < 0.0001). Multiple arachnoid cysts occurred in 30 patients. The most common locations were middle fossa (34%), retrocerebellar (33%), and convexity (14%). Middle fossa cysts were predominantly left-sided (70%, p < 0.001). Thirty-f...

Pediatric intracranial arachnoid cysts: comparative effectiveness of surgical treatment options

Abstract: A variety of surgical approaches for the treatment of pediatric intracranial arachnoid cysts exist. In an effort to identify the optimal surgical treatment for this disorder, we developed a decision analytic model to evaluate outcomes of four surgical approaches in children. These included open craniotomy for cyst excision, open craniotomy for cyst fenestration, endoscopic cyst fenestration, and cystoperitoneal shunting. Pooled data were used to create evidence tables, from which we calculated incidence, relative risks, and summary outcomes in quality-adjusted life years (QALYs) for the four surgical treatments. Our study incorporated data up to 5 years postsurgery. We analyzed 1,324 cases from 36 case series. There were no significant differences in outcome among the four surgical strategies. The QALYs (maximum of 5) for surgical approaches resulted in a range from 4.79 (for open craniotomy and excision) to 4.92 (for endoscopic fenestration). Overall quality of life is comparable between patients undergoing open craniotomy for cyst excision or fenestration, endoscopic fenestration, and cystoperitoneal shunting up to 5 years after surgery. While each approach offers unique advantages and disadvantages, an individualized treatment strategy should be employed in the setting of surgical outcome equipoise.

Exploring predictors of surgery and comparing operative treatment approaches for pediatric intracranial arachnoid cysts: a case series of 83 patients.

Abstract: OBJECT Although intracranial arachnoid cysts are a common incidental finding on pediatric brain imaging, only a subset of patients require surgery for them. For the minority who undergo surgery, the comparative effectiveness of various surgical approaches is debated. The authors explored predictors of surgery and compared operative techniques for pediatric patients with an intracranial arachnoid cyst seen at a tertiary care center. METHODS The authors reviewed records of pediatric patients with an intracranial arachnoid cyst. For each patient, data on baseline characteristics, the method of intervention, and surgical outcomes for the initial surgery were extracted, and cyst size at diagnosis was calculated (anteroposterior × craniocaudal × mediolateral). Baseline variables were analyzed as predictors of surgery by using logistic regression modeling, excluding patients whose surgery was not related to cyst size (i.e., those with obstructive hydrocephalus secondary to the cyst compressing a narrow CSF flow ...