Differentiation of Edematous, Tumoral and Normal Areas of Brain Using Diffusion Tensor and Neurite Orientation Dispersion and Density Imaging.

BACKGROUND: Presurigical planning for glioma tumor resection and radiotherapy treatment require proper delineation of tumoral and peritumoral areas of brain. Diffusion tensor imaging (DTI) is the most common mathematical model applied for diffusion weighted MRI data. Neurite orientation dispersion and density imaging (NODDI) is another mathematical model for DWI data modeling. OBJECTIVE: We studied whether extracted parameters of DTI, and NODDI models can be used to differentiate between edematous, tumoral, and normal areas in brain white matter (WM). MATERIAL AND METHODS: 12 patients with peritumoral edema underwent 3T multi-shell diffusion imaging with b-values of 1000 and 2000 smm-2 in 30 and 64 gradient directions, respectively. We fitted DTI and NODDI to data in manually drawn regions of interest and used their derived parameters to characterize edematous, tumoral and normal brain areas. RESULTS: We found that DTI parameters fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD) and radial diffusivity (RD) all significantly differentiated edematous from contralateral normal brain WM (p<0.005). However, only FA was found to distinguish between edematous WM fibers and tumor invaded fibers (p = 0.001). Among NODDI parameters, the intracellular volume fraction (ficvf) had the best distinguishing power with (p = 0.001) compared with the isotropic volume fraction (fiso), the orientation dispersion index (odi), and the concentration parameter of Watson distribution (κ), while comparing fibers inside normal, tumoral, and edematous areas. CONCLUSION: The combination of two diffusion based methods, i.e. DTI and NODDI parameters can distinguish and characterize WM fibers involved in edematus, tumoral, and normal brain areas with reasonable confidence. Further studies will be required to improve the detectability of WM fibers inside the solid tumor if they hypothetically exist in tumoral parenchyma.

Surgical outcome of anterior decompression in cervical spondylotic myelopathy in patients with less cord derangement.

AIM: CSM patients caused by osteophytic ridge or intervertebral disc herniation underwent anterior decompression and fusion were prospectively enrolled. The purpose was to elucidate the effects of decompression (anterior cervical discectomy and fusion) on myelopathic cord in milder cases, younger patients, and in short duration of the disease. METHODS: Forty-three patients with CSM were examined comprising Cooper and mJOA scale before and after surgery and followed for 12 months. RESULTS: Patients included in the study were 30 males and 13 females. The mean age of men was 50.9±13.2, and that of women was 46.8±11.8. The mean interval from symptoms onset to hospital presentation was 10.78±7.3 months. In lower limbs, among 31 with preoperative functional impairment, 25 remained unchanged, three improved and three worsened, which is not significant, and of 39 patients with preoperative upper limb functional impairments using Cooper's scale, 20 improved, 15 remained unchanged and 4 became worse (P=0.001). Recovery rate for mJOA score was 24.5±17.7%, for Cooper lower extremity score was 32.2±40.56% and for Cooper upper extremity score was 7.8±16.8%. The mean gain in mJOA was 0.84 (±0.57). CONCLUSION: Patients with short duration of symptom onset respond remarkably to decompression surgery. In patients with good condition that myelopathy has not established yet, perhaps mJOA is not a perfect and powerful scale for pre and postoperative assessment of patient.

Use of image guidance in endoscopic endonasal surgeries: a 5-year experience.

PROBLEMS/OBJECTIVES: Endoscopic endonasal surgery (EES) is standard practice in sinonasal disease and is becoming more accepted in the performance of anterior skull base resections. We report our experience with image-guided surgery (IGS) in difficult cases of paranasal sinus (PNS) and skull base pathologies and discuss advantages and disadvantages of this technique. METHODOLOGY: A retrospective chart review was performed for the period 2004-2009. Degree of PNS involvement, indication for IGS, incidence of major complications, need for revision surgery, and technical data regarding the system were gathered. RESULTS: Sixty-two of 86 patients were followed for at least one year and therefore included in the analysis. Indications for IGS were mostly revision surgery for polyposis (42%), chronic rhinosinusitis (CRS) of frontal and/or sphenoid sinuses (14.5%), skull base tumours (30.6%), and foreign body removal (4.8%). Revision rates after IGS in polyposis, CRS, and benign skull base tumours were 7.7%, 11.11%, and 7.1%, respectively. CONCLUSIONS: IGS is of particular benefit in the management of sinonasal polyposis, benign skull base tumours, palliative surgery, and foreign body removal. IGS may avoid trauma to the orbit and anterior skull base and reduces the rate of revision surgeries rendering more meticulous and complete operations possible. We also think it could be helpful for foreign body removal.

Extension of echinococcal spinal infestation extra- and intradurally after a decade of extinction.

Simultaneous intradural, extradural, vertebral and paravetebral invasion of hydatid cyst, pathologic fracture, and multiple vertebral involvement are all rare encountered conditions in echinococcal infestation. A 48-year-old man who had experienced a falling down trauma, 10 years ago, and at that time, because of L1 burst fracture, undergone on Harrington rod placement, admitted in our ward for newly started urinary retention and mild paresis of lower extremities. With imaging analysis and during surgery, we discovered the extension of echinococcal spinal infestation extra- and intradurally after a decade of extinction. We performed a double stage circumferential reconstruction and adjuvant long term chemotherapy. We closely monitor our patient neurologically and radiologically and believe that aggressive surgical treatment and sustained cyclical albendazole therapy can increase the quality of life and life expectancy.