Mufit Parlak

Effectiveness of low-level laser therapy in temporomandibular disorder

Objective: To investigate the effectiveness of low‐level laser therapy in the treatment of temporomandibular disorder and to compare treatment effects in myogenic and arthrogenic cases. Methods: Thirty‐five patients were evaluated by magnetic resonance imaging and randomly allocated to active treatment (n=20) and placebo treatment (n=15) groups. In addition to a daily exercise program, all patients were treated with fifteen sessions of low‐level laser therapy. Pain, joint motion, number of joint sounds and tender points were assessed. Results: Significant reduction in pain was observed in both active and placebo treatment groups. Active and passive maximum mouth opening, lateral motion, number of tender points were significantly improved only in the active treatment group. Treatment effects in myogenic and arthrogenic cases were similar. Conclusion: Low‐level laser therapy can be considered as an alternative physical modality in the management of temporomandibular disorder.

The contribution of diffusion-weighted MR imaging to distinguishing typical from atypical meningiomas

IntroductionAtypical/malignant meningiomas recur more frequently then typical meningiomas. In this study, the contribution of diffusion-weighted MR imaging to the differentiation of atypical/malignant and typical meningiomas and to the determination of histological subtypes of typical meningiomas was investigated.MethodsThe study was performed prospectively on 39 patients. The signal intensity of the lesions was evaluated on trace and apparent diffusion coefficient (ADC) images. ADC values were measured in the lesions and peritumoral edema. Student’s t-test was used for statistical analysis. P<0.05 was considered statistically significant.ResultsMean ADC values in atypical/malignant and typical meningiomas were 0.75±0.21 and 1.17±0.21, respectively. Mean ADC values for subtypes of typical meningiomas were as follows: meningothelial, 1.09±0.20; transitional, 1.19±0.07; fibroblastic, 1.29±0.28; and angiomatous, 1.48±0.10. Normal white matter was 0.91±0.10. ADC values of typical meningiomas and atypical/malignant meningiomas significantly differed (P<0.001). However, the difference between peritumoral edema ADC values was not significant (P>0.05). Furthermore, the difference between the subtypes of typical meningiomas and atypical/malignant meningiomas was significant (P<0.001).ConclusionDiffusion-weighted MR imaging findings of atypical/malignant meningiomas and typical meningiomas differ. Atypical/malignant meningiomas have lower intratumoral ADC values than typical meningiomas. Mean ADC values for peritumoral edema do not differ between typical and atypical meningiomas.

Brain abscess and cystic brain tumor: discrimination with dynamic susceptibility contrast perfusion-weighted MRI.

Differentiating between brain abscesses and cystic brain tumors such as high-grade gliomas and metastases is often difficult with conventional MRI. The goal of this study was to evaluate the diagnostic utility of perfusion MRI to differentiate between these pathologies. MRI was performed in 19 patients with rim-enhancing brain lesions (4 pyogenic abscesses, 8 high-grade gliomas, 7 metastases). In addition to standard MR sequences, trace diffusion-weighted MRI with apparent diffusion coefficient (ADC) maps and perfusion-weighted MRI by using a first-pass gadopentetate dimeglumine T2*-weighted gradient echo single-shot echo-planar sequence were performed. Relative cerebral blood volume (rCBV) ratios were obtained via the values of the capsular portions of the lesions and the normal white matter. All the abscesses had markedly hyperintense signals in trace diffusion images, whereas they had significant hypointense signals in ADC images. In perfusion-weighted images, the capsular portions of the abscesses demonstrated low colored areas compared with the normal white matter and the rCBV ratio calculated was 0.76 ± 0.12 (mean ± SD). All but two of the cystic tumors showed low signal intensity on trace diffusion-weighted images and high signal intensity on ADC maps. Hyperintense signal was found in two brain tumors mimicking brain abscesses on trace diffusion images. The rCBV values in high-grade gliomas and metastases were 5.51 ± 2.08 and 4.58 ± 2.19, respectively. The difference between abscesses and cystic tumors was statistically significant (P = 0.003). Perfusion MRI may allow the differentiation of pyogenic brain abscess from cystic brain tumors, making it a strong additional imaging modality in the early diagnosis of these two entities.

MR imaging in the detection of diffuse axonal injury with mild traumatic brain injury

Abstract Purpose: To evaluate the occurrence and distribution of mild traumatic brain injury (MTBI) caused by diffuse axonal injury (DAI) using magnetic resonance (MR) imaging and to attempt to correlate MR findings with post-concussion symptoms (PCS). Patients and methods: Forty MTBI patients (mean age: 32.5 years) with normal cranial computed tomography (CT) findings were examined with standard MR protocol including T1-weighted, T2-weighted, fluid attenuated inversion recovery (FLAIR), gradient echo (GRE) and diffusion-weighted (DW) sequences. MR imaging was performed within 24 hours of injury. The lesions were classified as DAI based on their location and morphologic appearance. Results: In MR imaging of five (12.5%) of the patients, the lesions compatible with DAI were observed. Four patients (10%) had the foci of low signal intensity compatible with hemorrhagic shear injury on the GRE sequence, and five (12.5%) patients had high signal intensity on FLAIR and DW sequence. Conclusion: MR imaging can be helpful in revealing DAI lesions in patients with normal CT scan findings after MTBI. FLAIR, GRE and DW sequences are superior to conventional spin-echo images in detecting DAI lesions.

Tau protein as a serum marker of brain damage in mild traumatic brain injury: Preliminary results

The objective of this study was to investigate the diagnostic value of serum tau protein in determining the severity of traumatic brain injury in patients with mild traumatic brain injury (mTBI) and high-risk patients. Adult patients who presented to our emergency department (ED) with mTBI over 1 year were prospectively enrolled. Patients underwent cranial computed tomography (CT) and were subdivided into high and low-risk groups, according to the probability of resultant intracranial injury. Serum tau levels of 60 patients and 20 healthy volunteers, who served as a control group, were measured. The mean age of the 60 patients (45 males, 15 females) was 32.5 years (range, 15–66 y). Mean Glasgow Coma Scale (GCS) score was 14±0.6. CT scans demonstrated intracranial injury in 11 patients (18.3%) and depressed fracture in 4 patients (6.7%). Serum tau levels of patients (188±210 pg/mL), compared with those of controls (86±48 pg/mL), were relatively higher; however, differences were not statistically significant (P=.445). Also, serum tau levels of high-risk patients (307±246 pg/mL) were significantly higher than those of low-risk patients (77±61 pg/mL) (P=.001). A total of 48 patients (80%) were accessible for follow-up after 6 months. Postconcussive syndrome was observed in 8 patients, 5 of whom had serum tau protein levels that were higher than those of the other 3 patients. However, no statistically significant difference was observed (P > .05). Investigators of the present study noted that serum tau levels in patients with mTBI were increased. Therefore, it is believed that this biomarker may prove helpful in identifying high-risk patients with mTBI. However, additional studies are needed to establish the diagnostic value of serum tau in detecting traumatic brain injury in patients with mTBI.

Meningiomas with conventional MRI findings resembling intraaxial tumors: can perfusion-weighted MRI be helpful in differentiation?

IntroductionTo investigate the contribution of perfusion-weighted MRI to the differentiation of meningiomas with atypical conventional MRI findings from intraaxial tumors.MethodsWe retrospectively analyzed 54 meningiomas, 12 glioblastomas and 13 solitary metastases. We detected 6 meningiomas with atypical features on conventional MRI resembling intraaxial tumors. The regional cerebral blood flow (rCBV) ratios of all tumors were calculated via perfusion-weighted MRI. The signal intensity-time curves were plotted and three different curve patterns were observed. The type 1 curve resembled normal brain parenchyma or the postenhancement part was minimally below the baseline, the type 2 curve was similar to the type 1 curve but with the postenhancement part above the baseline, and the type 3 curve had the postenhancement part below the baseline accompanied by widening of the curve. Student’s t-test was used for statistical analysis.ResultsOn CBV images meningiomas were hypervascular and the mean rCBV ratio was 10.58±2.00. For glioblastomas and metastatic lesions, the rCBV ratios were 5.02±1.40 and 4.68±1.54, respectively. There was a statistically significant difference in rCBV ratios between meningiomas and glioblastomas and metastases (P<0.001). Only one of the meningiomas displayed a type 2 curve while five showed a type 3 curve. Glioblastomas and metastases displayed either a type 1 or a type 2 curve. None of the meningiomas showed a type 1 curve and none of the glioblastomas or metastases showed a type 3 curve.ConclusionDifferentiating meningiomas with atypical conventional MRI findings from malignant intraaxial tumors can be difficult. Calculation of rCBV ratios and construction of signal intensity-time curves may contribute to the differentiation of meningiomas from intraaxial tumors.

The contribution of 3D-CISS and contrast-enhanced MR cisternography in detecting cerebrospinal fluid leak in patients with rhinorrhoea

The aim of this prospective study was to evaluate the value of unenhanced (three-dimensional constructive interference in steady state (3D-CISS)) and contrast-enhanced MR cisternography (CE-MRC) in detecting the localisation of cerebrospinal fluid (CSF) leak in patients with rhinorrhoea. 17 patients with active or suspected CSF rhinorrhoea were included in the study. 3D-CISS sequences in coronal and sagittal planes and fat-suppressed T1-weighted spin-echo sequences in three planes before and after intrathecal contrast media administration were obtained. Images were obtained of the cribriform plate and sphenoid sinus. In addition, high-resolution CT (HRCT) was performed in order to evaluate the bony elements. The leak was present in 9/17 patients with 3D-CISS and 10/17 patients with CE-MRC. The leak from the cribriform plate to the nasal cavity in six patients and from the sphenoid sinus in four patients was nicely shown by CE-MRC. Eight of those patients were surgically treated, but spontaneous regression of the symptoms in two precluded any intervention. The leak localisations shown with CE-MRC were fully compatible with surgical results. The sensitivities of HRCT, 3D-CISS and CE-MRC for showing CSF leakage were 88%, 76% and 100%, respectively. In conclusion, 3D-CISS is a non-invasive and reliable technique, and should be the first-choice method to localise CSF leak. CE-MRC is helpful in conditions when there is no leak or in complicated cases with a positive beta2-transferrin measurement.

Solitary metastases and high-grade gliomas: radiological differentiation by morphometric analysis and perfusion-weighted MRI

AIM To evaluate the value of morphometric analysis and perfusion-weighted magnetic resonance imaging (MRI) in differentiating solitary metastases from high-grade gliomas. MATERIALS AND METHODS Forty-eight tumours (22 high-grade gliomas and 26 solitary hemispheric metastases) were evaluated using conventional and perfusion-weighted MRI. T2-weighted, gradient-echo, echo-planar sequences were used for perfusion-weighted MRI. Relative cerebral blood volume (rCBV) ratios were calculated by dividing the rCBV of the intratumoural and peritumoural areas with the average CBV value of the normal white matter areas. Morphometric analysis was carried out by proportioning the area of peritumoural oedema to the mass area. Mann-Whitney U test and ROC curve analysis were applied for statistical analysis. P<0.05 was accepted as statistically significant. RESULTS Mean rCBV ratios of intratumoural areas of high-grade gliomas and metastases were 5.02+/-2.47 and 4.62+/-2.46, respectively. No statistically significant difference was found (p=0.515). rCBV ratios of peritumoural oedema were 0.89+/-0.51 in high-grade gliomas and 0.31+/-0.12 in metastases. The difference was statistically significant (p<0.001). According to the results of morphometric analysis, a statistically significant difference was present between the two tumour types (p<0.001). CONCLUSION Measuring the oedema: mass and rCBV ratios of the oedema surrounding the tumour prior to operation in solitary masses proved to be useful for differentiating metastases from high-grade gliomas.

Treatment of nasolacrimal duct obstruction in adults with polyurethane stent

PURPOSE To evaluate the efficacy of polyurethane nasolacrimal duct stents in the treatment of epiphora resulting from primary acquired nasolacrimal duct obstruction in adults. MATERIALS AND METHODS In 25 patients (21 women and four men with mean age of 44 years, range 20 to 74 years) with nasolacrimal duct obstruction, 28 hollow polyurethane stents designed by Song and associates were placed under fluoroscopic guidance. The obstruction was complete in 20 lacrimal drainage systems and partial in eight. The lacrimal sac size was normal or large on dacryocystogram in all lacrimal drainage systems. A Ritleng probe was introduced through the upper punctum and advanced past the obstruction. A guide wire with a flexible tip was then introduced through the probe, over which the stent was advanced in retrograde fashion and placed into the lacrimal sac and nasolacrimal duct. Clinical success was defined by the demonstration of a completely patent lacrimal drainage pathway through saline irrigation and no or minimal complaint of epiphora. RESULTS Stent placement was technically successful in 26 of 28 lacrimal drainage systems (93%). The mean time of fluoroscopy screening was 3.2 minutes (range, 1.4 to 5.8 minutes). The overall success rate was 82% (23 of 28 lacrimal drainage systems). Two stents were completely occluded. In one lacrimal drainage system with minimal epiphora, the stented drainage pathway was partially occluded. The patients were followed up from 4 to 22 months (mean, 7.2 months). CONCLUSIONS Retrograde placement of a hollow polyurethane nasolacrimal duct stent is a technique that is simple and well tolerated by patients. This method achieves a high success rate and may be suggested as a nonsurgical procedure for adults with primary nasolacrimal duct obstruction and proper lacrimal sac size. The Ritleng probe facilitates the procedure.

Evaluation of CSF flow patterns of posterior fossa cystic malformations using CSF flow MR imaging

IntroductionDifferential radiologic diagnosis of cystic malformations of the posterior fossa is often difficult with conventional imaging techniques because of overlapping features of these entities. Posterior fossa cystic malformations occupy the cerebrospinal fluid (CSF) spaces. They may create secondary dynamic effects on the movements of CSF. The aim of this study was to investigate CSF flow alterations in posterior fossa cystic malformations with CSF flow MR imaging.MethodsThe study included 40 patients with cystic malformations of the posterior fossa. The patients underwent cardiac-gated phase-contrast cine MR imaging. CSF flow was qualitatively evaluated using an in-plane phase-contrast sequence in the midsagittal plane. The MR images were displayed in a closed-loop cine format.ResultsTwelve of the patients had communicating arachnoid cyst, seven had non-communicating arachnoid cyst, ten had mega cisterna magna, six had Dandy-Walker malformation, two had Dandy-Walker variant, and three had Blake’s pouch cyst. CSF flow MR imaging indicated the regions of no, slow or higher flow, direction of flow, and abnormal cystic fluid motion. Each malformation displayed a distinct CSF flow pattern.ConclusionPhase-contrast cine MR imaging for CSF flow evaluation may be a useful adjunct to routine MR imaging in the evaluation of the cystic malformations of the posterior fossa because it can improve the specificity in differentiating such malformations.