The influence of various variables on the rate of pneumothorax and intrapulmonal hemorrhage associated with computed tomography (CT)-guided transthoracic needle biopsy of the lung were evaluated retrospectively. One hundred and thirty-three patients underwent CT guided biopsy of a pulmonary lesion. Two patients were biopsied twice. Variables analyzed were lesion size, lesion location, number of pleural needle passes, lesion margin, length of intrapulmonal biopsy path and puncture time. Eighteen-gauge (18G) cutting needles (Trucut, Somatex, Teltow, Germany) were used for biopsy. Pneumothorax occurred in 23 of 135 biopsies (17%). Chest tube placement was required in three out of 23 cases of pneumothorax (2% of all biopsies). Pneumothorax rate was significantly higher when the lesions were located in the lung parenchyma compared with locations at the pleura or chest wall (P < 0.05), but all pneumothorax cases which required chest tube treatment occurred in lesions located less than 2 cm from the pleura. Longer puncture time led to an increase in pneumothorax rate (P < 0.05). Thirty-seven (27%) out of 135 biopsies showed perifocal hemorrhage. Intrapulmonal biopsy paths longer than 4 cm showed significantly higher numbers of perifocal hemorrhage and pneumothorax (P < 0.05). Significantly more hemorrhage occurred when the pleura was penetrated twice during the puncture (P < 0.05). Lesion size <4 cm is strongly correlated with higher occurrence of perifocal hemorrhage (P < 0.05). Lesion margination showed no significant effect on complication rate. CT-guided biopsy of smaller lesions correlates with a higher bleeding rate. Puncture time should be minimized to reduce pneumothorax rate. Passing the pleura twice significantly increases the risk of hemorrhage. Intrapulmonal biopsy paths longer than 4 cm showed significantly higher numbers of perifocal hemorrhage as well as pneumothorax.

To optimize examination protocols of 16-row multi-detector CT (MDCT) of pelvis for dose reduction with regard to image quality. MDCT of pelvis was performed on 12 cadaver specimens with stepwise reduction of tube current from 160 mA (113, 80, 56, 40, 28) to 20 mA at 120 kV. Scan parameters were 16 x 1.5 mm collimation. Reconstructions of axial and coronal images were used for evaluation of cortex, trabeculum, image quality, image noise, acetabulum and iliosacral (ISJ) joints. After data were blinded, evaluation of images was done by three radiologists according to 5-point Likert scale. Accuracy of the observers in sorting films according to dose reduction was determined with kappa coefficient. Mean values of image evaluation were determined. Pronounced deterioration of image quality for all criteria was observed between 80 and 28 mA. Adequate image quality was obtained at 40 mA [effective dose (E): 2.2 mSv, CTDI(w): 2.8 mGy] for criterion detailed definition of acetabulum and ISJ and at 80 mA (E: 4.4 mSv, CTDI(w): 5.6 mGy) for remaining criteria. Moderate agreement was observed between the three observers (kappa coefficient: 0.31). All observers were excellent in arranging images according to decreasing dose. Using 16-row MDCT image quality of pelvis is acceptable at 80 mA and 120 kV. This translates into a dose reduction of 33% of average value of the nationwide survey of the German Roentgen Society (1999) for this type of examination.

Increased lumbar IDD in MRI goes along with an increased ODI. Thus, MRI is a strong indicator of a patient's clinical appearance. However, low back pain cannot be explained by imaging alone. Clinical correlation is imperative for an adequate diagnostic advance in patients with low back pain.

Needle puncture in a soft tissue environment using the navigational system Medarpa can be reliably performed and matches the accuracy achieved by a computed tomography-guided puncture technique.

AIMTo assess the correlation of lateral recess stenosis (LRS) of lumbar segments L4/5 and L5/S1 and the Oswestry Disability Index (ODI).METHODSNine hundred and twenty-seven patients with history of low back pain were included in this uncontrolled study. On magnetic resonance images (MRI) the lateral recesses (LR) at lumbar levels L4/5 and L5/S1 were evaluated and each nerve root was classified into a 4-point grading scale (Grade 0-3) as normal, not deviated, deviated or compressed. Patient symptoms and disability were assessed using ODI. The Spearman’s rank correlation coefficient was used for statistical analysis (P < 0.05).RESULTSApproximately half of the LR revealed stenosis (grade 1-3; 52% at level L4/5 and 42% at level L5/S1) with 2.2% and 1.9% respectively reveal a nerve root compression. The ODI score ranged from 0%-91.11% with an arithmetic mean of 34.06% ± 16.89%. We observed a very weak statistically significant positive correlation between ODI and LRS at lumbar levels L4/5 and L5/S1, each bilaterally (L4/5 left: rho < 0.105, P < 0.01; L4/5 right: rho < 0.111, P < 0.01; L5/S1 left: rho 0.128, P < 0.01; L5/S1 right: rho < 0.157, P < 0.001).CONCLUSIONAlthough MRI is the standard imaging tool for diagnosing lumbar spinal stenosis, this study showed only a weak correlation of LRS on MRI and clinical findings. This can be attributed to a number of reasons outlined in this study, underlining that imaging findings alone are not sufficient to establish a reliable diagnosis for patients with LRS.