Jun Hyung Cho, Jung Yong Ahn, Sung Uk Kuh, Dong Kyu Chin, and Young Sul Yoon
Keun Young Park, Jung Yong Ahn, Jun Hyung Cho, Young Chul Choi, and Kyu Sung Lee
✓Neuromyelitis optica (NMO) is a severe demyelinating syndrome defined principally by its tendency to affect optic nerves and the spinal cord selectively. Asymptomatic brain lesions have recently become a common finding in NMO, and symptomatic brain lesions do not exclude the diagnosis of this entity. The authors describe the case of a 12-year-old girl suffering from an unusually atypical form of NMO in which a brainstem lesion was mistaken for a brainstem glioma. Brainstem involvement in NMO exhibits variable features on neuroimaging and is confused with brainstem glioma in cases of extensive brainstem involvement in childhood. Careful differential diagnosis and proper treatment are vital for a favorable prognosis.
Kyung Hwan Kim, Doo-Sik Kong, Kyung Rae Cho, Min Ho Lee, Jung-Won Choi, Ho Jun Seol, Sung Tae Kim, Do-Hyun Nam, and Jung-Il Lee
Fractionated Gamma Knife radiosurgery (GKS) represents a feasible option for patients with large brain metastases (BM). However, the dose-fractionation scheme balanced between local control and radiation-induced toxicity remains unclear. Therefore, the authors conducted a dose-escalation study using fractionated GKS as the primary treatment for large (> 3 cm) BM.
The exclusion criteria were more than 3 lesions, evidence of leptomeningeal disease, metastatic melanoma, poor general condition, and previously treated lesions. Patients were randomized to receive 24, 27, or 30 Gy in 3 fractions (8, 9, or 10 Gy per fraction, respectively). The primary endpoint was the development of radiation necrosis assessed by a neuroradiologist blinded to the study. The secondary endpoints included the local progression-free survival (PFS) rate, change in tumor volume, development of distant intracranial progression, and overall survival.
Between September 2016 and April 2018, 60 patients were eligible for the study, with 46 patients (15, 17, and 14 patients in the 8-, 9-, and 10-Gy groups, respectively) available for analysis. The median follow-up duration was 9.6 months (range 2.5–25.1 months). The 6-month estimated cumulative incidence of radiation necrosis was 0% in the 8-Gy group, 13% (95% confidence interval [CI] 0%–29%) in the 9-Gy group, and 37% (95% CI 1%–58%) in the 10-Gy group. Being in the 10-Gy group was a significant risk factor for the development of radiation necrosis (p = 0.047; hazard ratio [HR] 7.2, 95% CI 1.1–51.4). The 12-month local PFS rates were 65%, 80%, and 75% in the 8-, 9-, and 10-Gy groups, respectively. Being in the 8-Gy group was a risk factor for local treatment failure (p = 0.037; HR 2.5, 95% CI 1.1–29.6). The mean volume change from baseline was a 47.5% decrease in this cohort. Distant intracranial progression and overall survival did not differ among the 3 groups.
In this dose-escalation study, 27 Gy in 3 fractions appeared to be a relevant regimen of fractionated GKS for large BM because 30 Gy in 3 fractions resulted in unacceptable toxicities and 24 Gy in 3 fractions was associated with local treatment failure.
Ho Jun Yi, Jung Eun Lee, Dong Hoon Lee, Young Il Kim, Chul Bum Cho, Il Sup Kim, Jae Hoon Sung, and Seung Ho Yang
Perilesional edema is a predominant mechanism underlying secondary brain injury after traumatic brain injury (TBI). Perilesional edema is characterized by inflammation, production of proinflammatory cytokines, and migration of peripheral immune cells into the brain. The nucleotide-binding domain and leucine-rich repeat (NLR) family pyrin domain–containing 3 protein (NLRP3) is a key component of secondary injury. Pioglitazone regulates NLRP3 and other inflammatory cytokines. In the present study, the role of NLRP3 and the pharmacological effects of pioglitazone were investigated in animal TBI models.
Brain contusion was induced in a weight drop model involving 3 groups of mice: C57 BL/6 (sham group), NLRP3 knockout (K/O group), and pioglitazone-treated mice (treatment group). The percentage of brain water content of the 3 groups of mice was compared over a period of time. Western blot, immunohistochemistry, and immunofluorescence analyses were conducted to investigate NLRP3-related inflammasomes and the effects of pioglitazone in the TBI models.
Brain edema was the highest on day 3 after TBI in the sham group. Brain edema in both the K/O and the treatment groups was lower than in the sham group. In Western blot, the expression of inflammasomes was higher after TBI in the sham group, but the expression of interleukin-1β, caspase-1, and NLRP3 was decreased significantly following treatment with pioglitazone. The expression of GFAP (glial fibrillary acidic protein) and Iba1 was decreased in both the K/O and treatment groups. In addition, confocal microscopy revealed a decrease in microglial cell and astrocyte activation following pioglitazone therapy.
The inflammasome NLRP3 plays a pivotal role in regulating cerebral edema and secondary inflammation. Interestingly, pioglitazone reduced cerebral edema and immune response after TBI by downregulating the effects of NLRP3. These results suggest that the clinical application of pioglitazone may be a neuroprotective strategy in TBI.
William S. Gibson, Aaron E. Rusheen, Yoonbae Oh, Myung-Ho In, Krzysztof R. Gorny, Joel P. Felmlee, Bryan T. Klassen, Sung Jun Jung, Hoon-Ki Min, Kendall H. Lee, and Hang Joon Jo
Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is an established neurosurgical treatment for the motor symptoms of Parkinson’s disease (PD). While often highly effective, DBS does not always yield optimal therapeutic outcomes, and stimulation-induced adverse effects, including paresthesia, muscle contractions, and nausea/lightheadedness, commonly occur and can limit the efficacy of stimulation. Currently, objective metrics do not exist for monitoring neural changes associated with stimulation-induced therapeutic and adverse effects.
In the present study, the authors combined intraoperative functional MRI (fMRI) with STN DBS in 20 patients with PD to test the hypothesis that stimulation-induced blood oxygen level–dependent signals contained predictive information concerning the therapeutic and adverse effects of stimulation.
As expected, DBS resulted in blood oxygen level–dependent activation in myriad motor regions, including the primary motor cortex, caudate, putamen, thalamus, midbrain, and cerebellum. Across the patients, DBS-induced improvements in contralateral Unified Parkinson’s Disease Rating Scale tremor subscores correlated with activation of thalamic, brainstem, and cerebellar regions. In addition, improvements in rigidity and bradykinesia subscores correlated with activation of the primary motor cortex. Finally, activation of specific sensorimotor-related subregions correlated with the presence of DBS-induced adverse effects, including paresthesia and nausea (cerebellar cortex, sensorimotor cortex) and unwanted muscle contractions (caudate and putamen).
These results suggest that DBS-induced activation patterns revealed by fMRI contain predictive information with respect to the therapeutic and adverse effects of DBS. The use of fMRI in combination with DBS therefore may hold translational potential to guide and improve clinical stimulator optimization in patients.
Report of three cases
Yang Kwon, Jun Seok Bae, Jae Myung Kim, Do Hee Lee, Soon Young Kim, Jae Sung Ahn, Jeong Hoon Kim, Chang Jin Kim, Byung Duk Kwun, and Jung Kyo Lee
✓ Tumors involving the optic nerve (optic glioma, optic nerve sheath meningioma) are benign but difficult to treat. Gamma knife surgery (GKS) may be a useful treatment. The authors present data obtained in three such cases and record the effects of GKS.