Predicting Isocitrate Dehydrogenase Mutation Status of Grade 2-4 Gliomas with Diffusion Tensor Imaging (DTI) Parameters Derived from Model-Based DTI and Model-Free Q-Sampling Imaging Reconstructions.

OBJECTIVE: To determine whether diffusion tensor imaging (DTI) parameters acquired with model-based DTI and model-free generalized Q-sampling imaging (GQI) reconstructions may noninvasively predict isocitrate dehydrogenase (IDH) mutational status in patients with grade 2-4 gliomas. METHODS: Forty patients with known IDH genotype (28 IDH wild-type; 12 IDH mutant) who underwent preoperative DTI evaluation on a 3-Tesla magnetic resonance imaging scanner were analyzed retrospectively. Absolute values obtained from model-based and model-free reconstructions were compared. Using the intraclass correlation coefficient, interobserver agreement was assessed for various sampling techniques. Variables having statistically significant distributions between IDH groups were subjected to a receiver operating characteristic (ROC) analysis. Using multivariable logistic regression analysis, independent predictors, if present, were identified and a model was developed. RESULTS: Six imaging parameters (3 from model-based DTI and 3 from model-free GQI reconstructions) showed statistically significant differences between groups (P < 0.001, power >0.97), with very high correlation to each other (P < 0.001). Age difference between the groups was statistically significant (P < 0.001). The optimal logistic regression model comprised a GQI-based parameter and age, which were independent predictors as well, producing an area under the ROC curve, accuracy, sensitivity, and specificity of 0.926, 85%, 75%, and 89.3%, respectively. Using the GQI reconstruction feature alone with a cut-off of 1.60, an 85% of accuracy was also achieved with ROC analysis. CONCLUSIONS: The imaging parameters acquired from model-based DTI and model-free GQI reconstructions, combined with the clinical variable age, may have the ability to noninvasively predict the IDH genotype in gliomas, either alone or in particular combinations.

Clinical Study of Decompressive Craniectomy in Children.

AIM: To evaluate the clinical characteristics of children who recently underwent decompressive craniectomy (DC) due to elevated intracranial pressure (ICP) correlated to head trauma or other causes, such as ischemic insult. MATERIAL AND METHODS: Twelve patients aged ≤17 years who underwent DC due to elevated ICP between 2013 and 2018 were included in the study. The clinical status of the participants, radiological characteristics, type and timing of surgery, and outcomes were recorded. RESULTS: Three female and nine male patients with a mean age of 10 years were included. The initial average Glasgow Coma Scale score was 6 (3-12). All patients presented with signs of diffuse cerebral edema and subdural hematoma of various sizes along with other intracranial pathologies. Only one patient required bilateral frontal craniectomy. In the postoperative period, three patients died, and three had severe disability. CONCLUSION: With the increasing use and success of DC in adults, this procedure can also be effective in children. Considering brain differences in children, large and well-structured clinical trials must be conducted to prevent complications and to identify the best technique, timing, and benefits of DC for children.

Intracranial cystic meningiomas: A series of six patients.

OBJECTIVE: Although meningiomas are the most common primary non-glial intracranial tumors, cystic meningiomas are quite rare. This study presents six cases in order to discuss the radiological and pathological features of cystic meningiomas. PATIENTS AND METHODS: Six patients with cystic meningiomas were included in the study. All patients underwent a cranial computed tomography scan and magnetic resonance imaging (MRI) evaluation, pre- and postoperatively. RESULTS: All patients presented with long standing headache dating back at least two years. There was no gender predominance in our series. Radiological evaluation revealed two parasagittal and two convexity meningiomas located at the frontal region. Two lesions were located at the tuberculum sellae and the foramen magnum. All of the tumors were totally excised (Simpson Grade I or II). Pathology results included meningothelial meningioma in three patients, angiomatous meningioma in two patients, and metaplastic meningioma in one patient. In two patients, the cystic meningiomas were resected with the use of sodium fluorescein (Na-Fl) under a YELLOW 560nm microscope filter. Na-Fl was found to be very useful in demonstrating the brain-tumor interface, and it was especially effective in resecting the cyst wall of the peritumoural cystic meningiomas. None of the patients had any complications, and no recurrences were noted in any of the patients within the mean follow-up period of 51 months (range: 16-102 months). CONCLUSION: It is important to note MRI changes specific to cystic meningioma and include meningiomas in the differential diagnosis of intracranial cystic lesions. The use of sodium fluorescein (Na-Fl) under a YELLOW 560nm microscope filter is a useful tool to differentiate the brain-tumor interface, as well as to identify the cyst wall in order to fully resect the tumor with the cystic component to avoid recurrence and achieve better clinical results.

Serum creatine phosphokinase levels as an indicator of muscle injury following lumbar disc surgery: Comparison of fully endoscopic discectomy and microdiscectomy.

OBJECTIVE: The aim of this study is to make a comparison between fully endoscopic lumbar discectomy (FELD) and conventional microdiscectomy (MD) by using pre- and postoperative serum creatine phosphokinase (CPK) levels in correlation with postoperative low-back pain. METHODS: Fortyfive consecutive patients who underwent surgery for lumbar disc herniation were allocated into three groups with 15 patients on each: (1) FELD with interlaminar approach (IL), (2) FELD with transforaminal approach (TF), (3) Conventional MD. Serum CPK levels pre- and 1, 6, 12 and 24h postoperatively, patients' body mass index (BMI), operation duration and hospital stays were recorded. The low-back pain pre- and postoperatively was assessed with the use of the 100mm visual analog scale (VAS) and the "Oswestry Disability Index" (ODI). RESULTS: There were 16 female (35.5%) and 29 male (64.5%) patients with a mean age of 44.1 years. CPK levels at 6th, 12th and 24th hours postoperatively were found significantly lower in TF and IL groups compared to MD group (p<0.004). Mean operation duration was significantly shorter in MD group (p: 0.014). There was a significant decrease in both the VAS and ODI scores after the surgery in all patient groups (p<0.001). Postoperative VAS scores were found significantly higher in MD group (p: 0.04). CONCLUSION: Minimal invasive nature of FELD procedures compared to the MD was substantiated by serum CPK levels in this study. To draw definitive conclusions regarding pain relief, larger patient samples should be evaluated, although postoperative VAS scores were found in favor of FELD.

Fully endoscopic interlaminar and transforaminal lumbar discectomy: short-term clinical results of 163 surgically treated patients.

OBJECTIVE: To evaluate the clinical outcomes of patients with lumbar disc disease undergoing fully endoscopic surgery at a single clinic. METHODS: Between August 2009 and January 2012, 163 patients (74 men and 89 women) underwent fully endoscopic lumbar discectomy. All patients were followed for 1 year after surgery. The Oswestry Disability Index and a visual analog scale were used to analyze outcomes. RESULTS: During the follow-up period, 114 (70%) patients had no complaints, 30 (18%) patients had occasional pain, and 19 (12%) patients had no improvement. During postoperative follow-up, 8 patients required repeat surgery for recurrence or residual fragments. Postoperatively, 4 patients experienced dysesthesia, which completely resolved in time. Neurologic deterioration occurred in 5 patients, 4 of whom recovered completely without any intervention. Dural tears occurred in 6 patients. CONCLUSIONS: Fully endoscopic interlaminar or transforaminal surgeries are safe and effective treatment modalities for lumbar disc herniations. Despite the difficulties of acquiring this new technique, good results can be achieved with sufficient experience.

Unilateral endoscopic optic nerve decompression for idiopathic intracranial hypertension: a series of 10 patients.

OBJECTIVE: Several surgical treatment modalities, including lumboperitoneal or ventriculoperitoneal shunt surgery, subtemporal decompression, endovascular venous sinus stenting, optic nerve decompression (OND), were used in the management of idiopathic intracranial hypertension (IIH). Each surgical technique has different advantages and disadvantages. Endoscopic OND is rarely used in the management of IIH. There are only four reported cases. The aim of this study is to describe the surgical results of patients treated with this less invasive surgical technique. METHODS: A series of 10 consecutive cases of unilateral OND was reviewed. Between December 2008 and December 2012 these patients underwent the endoscopic approach without nerve sheath opening. Presenting symptoms, neurological examination findings, magnetic resonance venography imaging results, fundoscopic and visual acuity examination findings, and automated perimetry test results were recorded. Perioperative results, including complications and length of hospital stay, were evaluated. Findings at follow-up evaluations were also recorded. RESULTS: This report is the first series of unilateral OND performed using the endoscopic approach. The mean patient age was 34.1 years (range, 9-49 years); there were nine female and one male patients. Visual impairment was the main symptom in this patient group, whereas headache was a secondary complaint. The patients were first managed with medical treatment for at least 3 months. Unilateral endoscopic OND was performed on the side with the most visual failure. Mean follow-up was 28.4 months (range, 8-55 months). The visual field defects and visual acuity improved in eight of nine patients, whereas papilloedema improved in seven of nine patients. Also headaches resolved in four of seven patients. There were no complications in this relatively small series. CONCLUSIONS: The surgical treatment of IIH by using the unilateral endoscopic OND technique is a safe and effective method in the hands of experienced surgeons with advanced endoscopic skills. A collaboration with the ophthalmology team is needed for the follow-up. Further studies with larger patient numbers is needed to compare unilateral endoscopic OND technique with the current techniques used in the surgical management of IIH.