Twinkling artifact on color Doppler ultrasound: an advantage or a pitfall?

The twinkling artifact (TA) or color comet-tail artifact is characterized by a rapidly changing mixture of red and blue color Doppler signals. Even though many diseases and clinical conditions have been shown to produce this artifact, its source is not clearly understood yet. The TA may provide additional information to gray-scale ultrasound findings in several clinical situations. However, there may be pitfalls to keep in mind. We must first be aware of the TA to benefit from the advantages and avoid the pitfalls. In this review, we aim to give practicing radiologists an overview of the mechanisms and clinical applications of the TA by illustrating sample cases we have encountered.

Patient doses from CT examinations in Turkey.

PURPOSE: We aimed to establish the first diagnostic reference levels (DRLs) for computed tomography (CT) examinations in adult and pediatric patients in Turkey and compare these with international DRLs. METHODS: CT performance information and examination parameters (for head, chest, high-resolution CT of the chest [HRCT-chest], abdominal, and pelvic protocols) from 1607 hospitals were collected via a survey. Dose length products and effective doses for standard patient sizes were calculated from the reported volume CT dose index (CTDIvol). RESULTS: The median number of protocols reported from the 167 responding hospitals (10% response rate) was 102 across five different age groups. Third quartile CTDIvol values for adult pelvic and all pediatric body protocols were higher than the European Commission standards but were comparable to studies conducted in other countries. CONCLUSION: The radiation dose indicators for adult patients were similar to those reported in the literature, except for those associated with head protocols. CT protocol optimization is necessary for adult head and pediatric chest, HRCT-chest, abdominal, and pelvic protocols. The findings from this study are recommended for use as national DRLs in Turkey.

Tear Osmolarity and Tear Function Changes in Patients with Acromegaly.

PURPOSE: Since acromegaly is a disease with various systemic complications, it may also have ophthalmologic consequences. The aim of the current study was to compare the tear osmolarity and tear function changes in patients with acromegaly with those in healthy controls. DESIGN: Prospective, cross-sectional study. MATERIALS AND METHODS: Fifty-nine consecutive patients with acromegaly and 62 age and gender matched healthy volunteers were enrolled in the study. Tear osmolarity measurement with TearLab Osmolarity System (Tearlab, San Diego, CA), tear film break-up time (TBUT) assessment, and the Schirmer test without anesthesia were performed in the same order in each group. Growth hormone (GH) and insulin like growth factor-1 (IGF1) levels were also determined in the study group. RESULTS: The mean TBUT was lower in acromegalic patients (9.1 ± 3.6 seconds) than in healthy controls (10.7 ± 2.9 s) (p = 0.009). The difference between the two groups in tear osmolarity and Schirmer test results (p = 0.08 and p = 0.9, respectively) was not statistically different. CONCLUSIONS: Acromegaly may a cause a decrease in TBUT in the affected patient. Preservation of normal tear osmolarity and normal Schirmer test results suggests that this might be due to effects on the meibomian glands.

Acromegaly and aging: a comparative cross-sectional study.

OBJECTIVE: Cognitive and functional geriatric assessment may change in acromegaly. Herein we aimed to determine at which points geriatric assessment of the cases with acromegaly differs from that of general elderly population. DESIGN: In this comparative cross-sectional study, a total of 30 cases with acromegaly (controlled n = 14, uncontrolled n = 16) and 30 gender and body-mass index-matched cases without acromegaly (control group, CG) above 60 years old were included. Cognitive functions were evaluated on the basis of the mini-mental state exam (MMSE). Affective status was determined using the geriatric depression scale. Activities of daily living (ADL) were ranked according to the Barthel index while instrumental activities of daily living (IADL) were graded on the basis of the Lawton scale. Nutritional status was evaluated using the mini-nutritional assessment (MNA). Body composition was measured through bioimpedance analysis. Functional mobility was determined using the Timed Up and Go test (TUG) and muscle strength with the handgrip strength test. RESULTS: Scores on the MMSE were significantly lower in the elderly cases with acromegaly than in the cases without acromegaly (p < 0.001). Dementia was more frequent in the acromegaly group than in the CG (p = 0.04). Total MNA scores were significantly lower in cases with acromegaly than in the CG (p = 0.006). More subjects in the acromegaly group (33%) were at greater risk of malnutrition than in the CG (3%) (p = 0.003). There was greater moderate functional impairment based on Barthel ADL in the acromegaly group than in the CG (p = 0.04). CONCLUSION: Acromegaly may impair cognitive functions, functional mobility and instrumental daily living activities in the geriatric population. With acromegaly, the risk of malnutrition may also increase.

Corneal endothelial cell density and morphology in patients with acromegaly.

OBJECTIVE: Acromegaly has various impacts on many organs. The ophthalmologic effects of acromegaly have not yet been investigated in detail. The aim of the current study was to evaluate qualitative and quantitative changes in corneal endothelial cells and central corneal thickness (CCT) of the patients with acromegaly. DESIGN: In this prospective, cross-sectional study, 128 eyes of 64 patients with acromegaly (female/male=40/24) and 208 eyes of 104 age and gender-matched healthy volunteers (female/male=69/35) were included. Endothelial cell density (ECD), cellular area (CA), coefficient of variation (CV) in cell size, percentage of hexagonal cells, and CCT were measured in patients with acromegaly and in healthy volunteers using the noncontact specular microscopy (SP-3000P: Topcon Corporation, Tokyo, Japan). RESULTS: ECD and CA were lower in cases with acromegaly than in controls (ECD in acromegaly: 2615.65 cell/mm(2) and in controls: 2700.35 cell/mm(2); p=0.002. CA in acromegaly: 382.30µm(2) and in controls: 400.30µm(2); p=0.02). In the entire group with acromegaly, the time elapsed since diagnosis was positively correlated with CA and was negatively correlated with ECD (r=+0.39, p=0.001 and r=-0.42, p=0.001). CONCLUSIONS: The endothelial layer of the cornea may be under risk of impairment with prolonged disease duration in acromegaly. Consistency of the corneal endothelium should be also sought during long-term follow-up of the cases with acromegaly.

Von Hippel Lindau disease with metastatic pancreatic neuroendocrine tumor causing ectopic Cushing's syndrome.

We present a 39-year-old woman who was previously diagnosed with Von Hippel Lindau Disease (VHLD). She had surgery and radiotherapy for cranial hemangioblastoma (HA) 11 years ago and had unilateral adrenalectomy for pheochromocytoma in another hospital 6 month prior to her admission to our center. Moon face, buffalo hump, central obesity, progressive weight gain and menstrual irregularities persisted after adrenalectomy. Her laboratory results were consistent with ectopic Cushing's syndrome (ECS). A pancreatic solid mass with a nodule on the left lung were revealed upon computed tomography. In addition, Gallium-68 Somatostatin Receptor PET confirmed the pancreatic involvement and demonstrated additional lesions on the left lung and in the aortocaval lymphatic system on the right side, suggesting metastatic pancreatic neuroendocrine tumor (PNET). Peptide receptor radionuclide therapy (PRRT) with [177Lutetium-DOTA0,Tyr3] octreotate was performed on the patient, with no side effects observed. She was discharged from the hospital 10 days after the first cycle.

The benefit of expiratory-phase quantitative CT densitometry in the early diagnosis of chronic obstructive pulmonary disease.

PURPOSE: We aimed to compare the inspiratory and expiratory quantitative computed tomography (CT) densitometric data of healthy volunteers, individuals with chronic obstructive pulmonary disease (COPD) risk, and COPD patients to aid in the early diagnosis of COPD. MATERIALS AND METHODS: Of the study patients, 14 were healthy volunteers (Group I), 12 were patients at risk for COPD (Group II), and 13 were COPD patients (Group III). The high-resolution CT was performed at three levels (the upper, middle, and lower parts of the lungs). All images were evaluated with a specific program for the segmentation of pulmonary parenchyma. The mean lung density (MLD) was measured, and the emphysema index (EI) was calculated using this program. RESULTS: Both MLD values and calculated EI ratios showed significant differences between Groups I and III, and Groups II and III in both expiratory and inspiratory phases (P < 0.05). However, in the comparison of healthy volunteers and patients at risk for COPD (Group I and II), only expiratory-phase MLD values showed statistically significant difference (P < 0.001). CONCLUSION: In patients at risk for COPD, expiratory-phase MLD measurements can be used as an early diagnostic method.

The results of computed tomography guided tru-cut transthoracic biopsy: complications and related risk factors.

INTRODUCTION: Transthoracic biopsy (TTB) is a well-defined and effective method used for pathologic sampling in the diagnosis of the pulmonary lesions. It is less invasive in comparison to surgical procedures. In addition, diagnostic rate of tru-cut biopsy is higher than that of fine needle aspiration biopsy (FNAB) especially for benign lesions. In this study, we presented tru-cut transthoracic biopsy (TTB) procedure results and the frequency of TTB complications with related risk factors. MATERIAL AND METHODS: A total of 102 patients were evaluated by CT scan guided tru-cut TTB in the diagnosis of lung lesions between January 2003 and December 2007. The complications due to tru-cut TTB were recorded. The factors such as the lesion depth, the lesion size, and the emphysematous changes that accompany the lesion were evaluated through χ(2) test. RESULTS: Among the samples, 51% malignancy and 49% benign pathology were observed. Pneumothorax developed in 15.7% of the 102 procedures. It was found that the lesion's distance from the pleura, the size of the lesion, and emphysematous changes around the lesion significantly increased the risk of pneumothorax. DISCUSSION: The tru-cut biopsy complications are similar to those of FNAB. In the centers where cytologic examination is insufficient in the diagnosis of lung lesions, tru-cut biopsy should be routinely performed as it is a reliable biopsy technique compared to FNAB.

No evidence of RET germline mutations in familial pituitary adenoma.

Pituitary adenomas are common in the general population. Although most of them are sporadic, some occur in a familial setting. In familial pituitary adenoma patients it is common that no germline defects are found after screening of aryl hydrocarbon receptor interacting protein (AIP) and other genes known to underlie the condition, suggesting the existence of yet unknown predisposition genes. Recently, the RET proto-oncogene was found to be a novel in vivo interaction partner of AIP in the pituitary gland. Here, we have screened patients from 16 AIP mutation negative (AIPmut-) pituitary adenoma families for RET germline mutations to assess whether RET could play a role in pituitary adenoma predisposition, similar to AIP. We found five novel germline RET changes: one in RET Exon 4 and the rest in noncoding regions of RET. Two changes, c.1560*G > A and -1285 G > A, were segregated in affected family members. We also analyzed the RET region with enhancer element locator (EEL) to identify RET regulatory elements, and to see whether the changes resided in these. None of the variants mapped to the regions predicted by EEL. Expression of RET was examined in ten AIPmut- and seven AIP mutation positive (AIPmut+) somatotropinomas by immunohistochemistry, with a trend showing reduced expression in the latter (P = 0.05). We conclude that the RET variants are presumably not related to pituitary adenoma predisposition, although reduced RET expression may play a role in AIP-related genesis of somatotropinomas.

Fast MRI evaluation of pulmonary progressive massive fibrosis with VIBE and HASTE sequences: comparison with CT.

PURPOSE: The aim of this prospective study was to evaluate the diagnostic utility of volumetric interpolated breath-hold examination (VIBE) and half-Fourier-acquisition single-shot turbo spin-echo (HASTE) fast magnetic resonance imaging (MRI) sequences in the evaluation of pulmonary progressive massive fibrosis (PMF) in comparison with computed tomography (CT) imaging. If fast MRI is proven to be diagnostically significant, this modality can be used for diagnosis and follow-up studies of PMF patients. MATERIALS AND METHODS: Twenty-two PMF lesions from 20 coal workers were evaluated. After CT imaging, patients underwent pre-contrast VIBE, contrast-enhanced VIBE, and HASTE MRI studies for detection and evaluation of the PMF lesions. Measurements of the three groups were evaluated with intra-class coefficients. Correlation levels between sizes, image quality, and artifact were evaluated with linear Pearson correlation analysis. RESULTS: There was almost perfect agreement among radiologists for lesion detection with kappa analysis. There was significant agreement between three MRI study groups and gold standard CT images. We found the best agreement values with contrast- enhanced VIBE images for lesion detection and image quality in comparison with CT imaging. Presence of artifact was also lowest with this protocol. CONCLUSION: With fast MRI sequences in pulmonary imaging, image quality has significantly improved being very close to that of CT studies. In this study, contrast-enhanced VIBE protocol provided the best depiction of PMF lesions. This protocol may be an alternative choice for CT, avoiding the use of iodinated contrast material and minimizing exposure to ionizing radiation for follow-up studies.

Incidental detection of granulomatous prostatitis by F-18 FDG PET/CT in a patient with bladder cancer: a rare complication of BCG instillation therapy.

A 62-year-old man with transitional-cell carcinoma of the bladder had undergone transurethral resection and adjuvant treatment with several intravesical instillations of bacillus Calmette-Guerin 10 months earlier. The patient was referred for F-18 FDG PET/CT after detection of mediastinal lymphadenopathy on follow-up CT. Beside moderately increased FDG uptake in bilateral hilar and bronchopulmonary lymph nodes, focally intense FDG uptake was detected in the right lobe of the prostate. Histopathologic evaluation revealed granulomatous prostatitis which is a recognized rare complication of intravesical instillation of BCG during the treatment of superficial bladder cancer.

MRCP vs. ERCP in the evaluation of biliary pathologies: review of current literature.

OBJECTIVE: Recently developed magnetic resonance (MR) techniques permit fast and correct imaging of the entire biliary tree with a high spatial resolution. The aim of this study was to compare the diagnostic potential of one of these new MR sequences in magnetic resonance cholangiopancreatography (MRCP) procedure and endoscopic retrograde cholangiopancreatography (ERCP) with review of current literatures. METHODS: A total of 295 patients were enrolled in this study prospectively. Of these, 11 were excluded from the study due to inadequate MRCP image quality and 15 more were excluded due to unsuccessful cannulation during ERCP. Thus, finally 269 patients (124 men and 145 women with a mean age of 57 years; range: 23-92 years) were included. The MRCP procedure was performed before the ERCP in all cases. All MRCP studies were performed with recently developed new MR technique using a heavily T2-weighted turbo spin echo (TSE) sequence. This TSE sequence is currently one of the most widely used multiplanar 3-D MR technique, having a high spatial resolution and fast imaging capacity. RESULTS: The study participants were classified into four main groups; normal into group I, stone disease into group II, tumor into group III and others into group IV. Group I consisted of 228 patients who had a normal pancreaticobiliary tree on both the MRCP and ERCP examinations. In group II there were 18 patients, for whom the MRCP had a 88.9% sensitivity and a 100% specificity for diagnosing biliary stone disease. Its positive predictive value (PPV), negative predictive value (NPV) and accuracy rates were 100%, 99.2% and 99.2%, respectively. The MRCP had a 100% sensitivity and a 100% specificity for 20 patients in group III. It also had 100% PPV, 100% NPV, and 100% total accuracy rates in this group. In three patients in group IV, the MRCP had a 100% sensitivity and specificity, respectively. Its PPV, NPV and accuracy were 100%, 100% and 100%, respectively. CONCLUSION: MRCP is used with increasing frequency as a non-invasive alternative to ERCP and the diagnostic results of MRCP with a heavily T2-weighted TSE MR sequence and ERCP are comparable with high accuracy in various hepatobiliary pathologies.

Large genomic deletions in AIP in pituitary adenoma predisposition.

CONTEXT: Germline mutations in AIP have been recently shown to cause pituitary adenoma predisposition (PAP). Subsequently, many intragenic germline mutations have been reported, both in familial and in sporadic settings. OBJECTIVE: Our objective was to evaluate the possible contribution of large genomic germline AIP deletions, an important mutation type in tumor predisposition syndromes, in PAP. DESIGN: Here, we applied the multiplex ligation-dependent probe amplification assay to examine whether large genomic AIP or MEN1 alterations account for a subset of PAP cases. PATIENTS: The study was performed on familial and sporadic pituitary adenoma cases of European origin, which had previously tested negative for germline AIP and MEN1 mutations by sequencing. RESULTS: Two of 21 pituitary adenoma families (9.5%) were found to harbor an AIP deletion. No copy number changes were detected among 67 sporadic pituitary adenoma patients. No MEN1 deletions were found. CONCLUSIONS: The present study shows that large genomic AIP deletions account for a subset of PAP. Therefore, in suspected PAP cases undergoing counseling and AIP genetic testing, multiplex ligation-dependent probe amplification could be considered if direct sequencing does not identify a mutation.

Early adolescent primary ciliary dyskinesia associated with broncholithiasis.

Primary ciliary dyskinesia (PCD), is a rare congenital disease group, and contained Kartageners syndrome. This syndrome is characterized with situs viscerum inversus, sinusitis and bronchiectasis. In some elderly patients, broncholithiasis may be associated with PCD. The coexistence of early adolescence PCD and broncolithiasis has not been reported yet. We report here a case of a 14-year-old early adolescent male who had typically presented as PCD-based Kartageners syndrome and developed broncholithiasis which diagnosed with computed tomography.

Management of Cushing's disease using cavernous sinus sampling: effectiveness in tumor lateralization.

OBJECTIVE: The aim of this study was to determine the accuracy of bilateral cavernous sinus sampling (CSS) in preoperative tumor lateralization (right/left) within the pituitary in patients with Cushing's disease (CD). PATIENTS AND METHODS: The study consisted of 26 consecutive patients who had undergone CSS followed by transsphenoidal surgery (TS) for CD between 2000 and 2006 at our institution. The magnetic resonance imaging (MRI) of the selected patients either revealed a normal pituitary or a lesion

Investigation of microalbuminuria in nondiabetic, normotensive obese women.

AIM: To investigate if obesity which is not accompanied by diabetes and/or hypertension is associated with microalbuminuria in female patients. MATERIALS AND METHODS: A total of 77 obese female patients from the Outpatient Clinic of Endocrinology of Istanbul University Cerrahpasa Medical Faculty and 30 age-matched, lean, healthy women were enrolled in the study. Patients with accompanying diabetes mellitus, hypertension, obesity associated with any endocrine abnormality, hepatic or renal disease, fever, infectious disease, malignancy were excluded. Weight, height, body-mass index (BMI), waist circumference, waist/hip ratio (WHR) and systolic and diastolic blood pressures were recorded. Albumin excretion in 24-hour urine samples (UAE) were measured using SYNCHRON LX System with MA Microalbumin kit in two separate 24-hour urine samples from every patient. Statistical analysis was performed using t-test and Pearson's correlation in SPSS 12.0 for Windows Program. RESULTS: The median albumin excretion in 24-hour urine sample was similar in obese and control groups (12.01 +/- 10.69 mg/day vs 9.35 +/- 4.09 mg/day; p= 0.211). There were no correlations between the albumin excretion in 24 hour urine samples and BMI, waist circumference, WHR, systolic or diastolic blood pressure. CONCLUSION: Diabetes mellitus and hypertension are known to be associated with microalbuminuria. In our study, microalbuminuria was not detected in obese women without diabetes and/or hypertension and UAE was similar in obese and lean women.

Germline CDKN1B/p27Kip1 mutation in multiple endocrine neoplasia.

CONTEXT: Germline mutations in the MEN1 gene predispose to multiple endocrine neoplasia type 1 (MEN1) syndrome, but in up to 20-25% of clinical MEN1 cases, no MEN1 mutations can be found. Recently, a germline mutation in the CDKN1B gene, encoding p27(Kip1), was reported in one suspected MEN1 family with two acromegalic patients. OBJECTIVE: Our objective was to evaluate the role of CDKN1B/p27(Kip1) in human tumor predisposition in patients clinically suspected of MEN1 but testing negative for MEN1 germline mutation as well as in familial and sporadic acromegaly/pituitary adenoma patients. DESIGN: Genomic DNA was analyzed for germline mutations in the CDKN1B/p27(Kip1) gene by PCR amplification and direct sequencing. SETTING: The study was conducted at nonprofit academic research and medical centers. PATIENTS: Thirty-six Dutch and one German suspected MEN1 patient, who previously tested negative for germline MEN1 gene mutations, were analyzed. In addition, 19 familial and 50 sporadic acromegaly/pituitary adenoma patients from Europe and the United States were included in the study. MAIN OUTCOME MEASURES: We analyzed germline CDKN1B/p27(Kip1) mutations in individuals with pituitary adenoma and MEN1-like features. RESULTS: A heterozygous 19-bp duplication (c.59_77dup19) leading to a truncated protein product was identified in one Dutch patient with suspected MEN1 phenotype, pituitary adenoma, carcinoid tumor, and hyperparathyroidism (one of 36, 2.8%). No mutations were detected in either familial or sporadic acromegaly/pituitary adenoma patients. CONCLUSIONS: Our results support the previous finding that germline CDKN1B/p27(Kip1) mutations predispose to a human MEN1-like condition. However, such mutations appear uncommon in suspected MEN1 cases and rare or nonexistent in familial or sporadic acromegaly/pituitary adenoma patients.

Pituitary adenoma predisposition caused by germline mutations in the AIP gene.

Pituitary adenomas are common in the general population, and understanding their molecular basis is of great interest. Combining chip-based technologies with genealogy data, we identified germline mutations in the aryl hydrocarbon receptor interacting protein (AIP) gene in individuals with pituitary adenoma predisposition (PAP). AIP acts in cytoplasmic retention of the latent form of the aryl hydrocarbon receptor and also has other functions. In a population-based series from Northern Finland, two AIP mutations account for 16% of all patients diagnosed with pituitary adenomas secreting growth hormone and for 40% of the subset of patients who were diagnosed when they were younger than 35 years of age. Typically, PAP patients do not display a strong family history of pituitary adenoma; thus, AIP is an example of a low-penetrance tumor susceptibility gene.

Enhancement kinetics of normal ovaries on dynamic contrast-enhanced MR imaging.

OBJECTIVE: The objective was to determine the enhancement kinetics of the normal ovaries in healthy women on dynamic contrast-enhanced magnetic resonance (DCE-MR) imaging. METHOD: Twenty-one women who had normal ovulatory cycles (volunteers; mean age=26.3 years, range=20-35), normal hormone profile, and apparently normal ovaries on ultrasonographic scan underwent DCE-MR imaging on a 1.5-T system (Philips Medical Systems, Gyroscan Intera, Best, The Netherlands) using a phased array pelvic coil. Sequential images with an imaging time of 14.4s per dynamic image were acquired before and after injection of a contrast bolus at 30s and at 1, 2, 3, 4, and 5 min. On postprocessing examination the following measurements were obtained for ovarian and muscle tissue: the signal intensity value per dynamic study, early phase enhancement rate, time to peak enhancement (Tp), and percentage of wash-out at the fifth minute were determined. Data of the ovaries and skeletal muscle were compared using Wilcoxon's rank sum test. RESULTS: Most of the mean values of the postcontrast signal intensity measurements, the mean values of the early phase enhancement rate, and the percentage of wash-out at the fifth minute were found to be significantly higher in ovary than in muscle (p<0.05). The mean values of Tp, on the other hand, were nonsignificantly lower in ovary than in muscle (p>0.05). On the examination of the mean signal intensity-time data graphics the ovary showed a tendency toward greater and quicker enhancement and wash-out. CONCLUSION: In our opinion, DCE-MR imaging, which determines contrast enhancement such as wash-in and wash-out kinetics, can provide knowledge of ovarian vascularization. Thus, by using DCE-MR imaging, determination of these vascularization changes in various ovarian diseases may provide us with additional parameters in the diagnosis of and treatment strategies for ovarian diseases.

Evaluation of the hippocampus and the anterior cingulate gyrus by proton MR spectroscopy in patients with post-traumatic stress disorder.

PURPOSE: Previous studies have shown that post-traumatic stress disorder (PTSD) is associated with lymbic system dysfunction. The purpose of this study is to evaluate whether or not the neuronal integrity in hippocampus and anterior cingulate gyrus is affected in PTSD as assessed by proton magnetic resonance spectroscopy. MATERIALS AND METHODS: Single voxel MRS was performed in 10 PTSD patients and 6 healthy subjects in two cerebral areas highly involved in the pathophysiology of PTSD (the hippocampus and the anterior cingulate gyrus). Spectra were obtained using PRESS sequence. Voxel sizes were 3.7 cm3 (hippocampus) and 6-7.2 cm3 (anterior cingulate gyrus). Metabolite ratios of NAA/Cr and Cho/Cr were calculated and compared to the control subjects. The severity of PTSD in the patient group was evaluated by Clinician-Administered PTSD Scale. RESULTS: Analysis of the proton MR spectra showed reductions in NAA/Cr ratio in bilateral hippocampus of PTSD subjects as compared to normal controls (p < 0.001), whereas Cho/Cr ratios were increased (p < 0.001). Reductions in NAA/Cr ratio were found in the the anterior cingulate gyrus of PTSD subjects as compared to normal controls (p < 0.01), whereas Cho/Cr ratios did not differ significantly (p > 0.05). CONCLUSION: Changes in the metabolite ratios provide support for either neuronal dysfunction or neuronal loss both in the hippocampus and the anterior cingulate gyrus and may be associated with reduced neuronal integrity. Further studies with MRS in larger patient populations are needed to clarify the relationship between brain structures and neurobiology of PTSD.