MRI detection of cerebral lesions in post-traumatic anisocoria: specificity and prognostic significance.

AIM: To identify whether increased numbers of brainstem lesions are found in the presence of a post-traumatic pupillary function disturbance and classify them anatomically. MATERIALS AND METHODS: In this study, a diagnostic magnetic resonance imaging (MRI) examination was performed within 8 days after traumatic brain injury (TBI) in patients who had been unconscious for more than 24 hours post-TBI. The Glasgow Outcome Scale was evaluated 6 months after TBI. The data obtained from 140 consecutively enrolled patients between 2005 and 2011 were analysed. The clinical study parameter comprised the development of post-traumatic anisocoria at least once over the course between onset of trauma and diagnostic MRI, as a yes/no decision. Significance was presumed at p≤0.05. RESULTS: A total of 57 patients (41%) were found to have a lesion at MRI without involvement of the brainstem; in 83 (59%) the brainstem was (multiple) affected. Of the latter, 66 (46%) of patients had lesions in the midbrain, 38 (27%) in the pons, and seven (5%) in the medulla oblongata. By the time of MRI, anisocoria had been diagnosed in 45 (32%) patients. Mortality was highest, at 58%, in patients with anisocoria and a midbrain lesion, whilst it was 23% in those with anisocoria and no lesion in the midbrain. Mortality was 33% in relation to a midbrain lesion without anisocoria. CONCLUSION: Overall, the study demonstrated that there is a significant correlation between midbrain lesions and post-traumatic anisocoria in unconscious trauma patients. A brainstem lesion in this case can be assumed to be a pathomorphological correlate of anisocoria. The rate of damage to the midbrain was approximately 50% in cases of transient anisocoria. It can be assumed in this situation that there are functional disorders of the peripheral oculomotor nerve or identifiable/unidentifiable lesions of the brainstem.

[Linked Prosthesis for the Proximal Interphalangeal Joint: 17-Year Long-Term Results]. / Gekoppelte Fingermittelgelenksprothese - Verlauf über 17 Jahre.

BACKGROUND/PURPOSE: Joint replacement is a widely used procedure to treat painful osteoarthritis of the proximal interphalangeal joint. From 1996 to 1999, 16 patients received 19 hinged, piston-based DIGITOS prostheses in our department. In 2007, the 7-year clinical course of 14 patients (17 devices) was published in this journal. Now 12 of these patients (15 devices) have been followed with an average history of 17 years, and the preoperative data has been compared with the results after 7 and 17 years, respectively. PATIENTS AND METHODS: The patients were 10 women and 2 men, whose average age at the time of the preoperative examination was 63 (48-69) years. Replacements were performed on the index (6), middle (6), and ring finger (3). There were 14 idiopathic osteoarthritic changes and 1 posttraumatic osteoarthritic change. Follow-up included a clinical (range of motion in the proximal interphalangeal joint, extension lag, pain) and radiological examination. In addition, the DASH score was obtained and the patients were asked whether or not they would undergo the same surgery again. The results after 7 and 17 years were reviewed for statistically significant differences. RESULTS: While there were significant changes regarding extension lag and flexion in the first 7 years after replacement of the proximal interphalangeal joint, only minor changes were observed between 7 and 17 years after surgery. While the prosthesis was in its correct position in the first 2 years after implantation, all prostheses exhibited radiolucent lines after 4 years and periprosthetic osteophytes after 5 years. 17 years after surgery, the radiolucent lines had not increased at all and the osteophytes had increased insignificantly compared with the 7-year findings. None of the patients reported pain; all of them said that they would undergo the same surgical procedure again. CONCLUSION: While there were significant clinical and radiological changes in the first 7 years after replacement of the proximal interphalangeal joint by a linked DIGITOS prosthesis, only minor changes were observed between 7 and 17 years after surgery.

[Simulated Total Wrist Fusion and its Influence on Hand Grip Function]. / Einfluss der simulierten Handgelenksarthrodese auf die Greiffunktion der Hand.

BACKGROUND: Wrist fusion is still a common treatment for patients with advanced stage arthritis. Since patients are often intimidated by the functional limitations, we intended to evaluate the influence of the lack of wrist motion in different positions on the dynamic grip function and the grip strength of the hand. METHODS: We simulated wrist fusion in 20° extension and 20° flexion and evaluated the following grip types: fist closure, 2 different power grips, pinch grip and precision grip. A TUB sensor glove was used, which allowed us to dynamically record the range of motion (ROM) of the finger joints as well as grip strength. Nineteen healthy subjects participated and all types of grips were performed using a standardised protocol with and without simulated wrist fusion. RESULTS: Lack of wrist motion in 20° extension had no relevant effect on the fingers' ROM, grip speed or strength. Simulated fusion in 20° flexion also had no influence on ROM or grip speed, rejecting our hypothesis that a tenodesis effect of the extensors in flexion would decrease ROM in the finger joints and grip speed. However, we were able to show a significant decrease of grip strength in flexion compared with extension or healthy wrists. The decrease averaged between 23 and 42% of healthy values, depending on the grip type. There was no change in strength distribution among the fingers. CONCLUSION: We didn't find any impact of lack of wrist motion on finger movement during forceful hand grip at normal speed. However, a significant loss of grip strength in flexed position of the wrist joint should be considered in patients with an indication for bilateral wrist fusion.

[How do physicians code the motoric variable of the Glasgow-Coma-Score?]. / Wie kodieren Ärzte die motorische Antwort im Glasgow-Coma-Score?

A mere 14% gave the right answer according the guidelines: Code the "best motoric answer" of the "upper limb". 86% coded the Glasgow-Coma-Score for the motoric variable falsely and inconsistently. Additionally, the rate of correct answers were higher in physicians in training (37.5%) than in qualified and certified emergency doctors (5%). Emergency doctors post training stated in 68% instances that the variable should be coded according to the neurological results at the upper or lower extremity. Furthermore, they stated that the worst neurological result should be coded (43%). From our data, it appears that the coding of the motoric variable is not done according to the guidelines or is done inconsistently. There are compelling reasons for coding the worst result. However, this procedure is contrary to the guidelines presented by literature. These guideline have never been withdrawn. Emergency doctors obviously code the motoric variable of the Glasgow-Coma-Score with knowledge about the pathophysiology of traumatic brain injuries. The Glasgow-Coma-Score is used for coding the level of consciousness at the site of accident, on admission, for prognosis, in clinical studies and in forensic controversies. Its sensitivity for depth of coma depends on the quality of coding the motoric answer. We interviewed 165 emergency doctors (in training and post training) about the guidelines for coding the motoric variable of the Glasgow-Coma-Score.

Decerebrate posturing following traumatic brain injury: MRI findings and their diagnostic value.

AIM: To determine the pathomorphological and clinical background to decerebrate posturing in humans following serious traumatic brain injury. MATERIALS AND METHODS: One hundred and twenty patients who had been unconscious for more than 24 h underwent diagnostic MRI within 8 days after trauma. The presence of decerebrate rigidity as the clinical parameter was correlated to MRI findings, such as traumatic lesions in defined brain areas. Significance was presumed as p < 0.05. RESULTS: On the day of MRI 43 (36%) patients exhibited decerebrate posturing: 19 (23%) cases were unilateral and 24 (77%) bilateral. There was a significant correlation between midbrain lesions and the presence of rigidity. If a midbrain lesion was found in the absence of pontine lesions, decerebrate rigidity could be concluded (p < 0.05). There was no significant correlation to the rigidity in the case of midbrain lesions accompanied by pontine lesions, and no correlation to the rigidity could be detected for other regions of the brain. Both the occurrence of decerebrate posturing and the detection of brainstem lesions at MRI correlated with the Glasgow Outcome Scale. The combination of both parameters improved the probability of predicting the outcome. CONCLUSION: The rate of decerebrate posturing increases significantly in the presence of midbrain lesions. The presence of pontine lesions appears to be of secondary importance. The chances of predicting the Glasgow Outcome Scale are improved by the combination of clinical information (decerebrate posturing) and radiological parameters (type of brainstem lesion).

[The histological confirmation of diffuse axonal injury in severe brain injury survivors]. / Der histologische Nachweis des diffusen axonalen Hirnschadens bei Überlebenden schwerer Schädel-Hirntraumen.

Diffuse axonal injury (DAI) plays a major role after traumatic brain injury (TBI). Its imaging is based on computed tomography (CT) or magnetic resonance imaging (MRI). However, DAI is a histological diagnosis. Histopathological findings on survival after TBI are very rare. Hence, it is unclear whether the neuroradiological findings are of clinical relevance. Cerebral specimens were taken in 24 patients with TBI requiring surgery. The presence of histopathological evidence for DAI was evaluated. Specimens were taken from an extracranial brain prolapse (n = 2) and from peripheral parts of a brain contusion (n = 22). Histological findings were correlated to the clinical course and the neurological status. A clinical follow-up was carried out 6 months after the surgery using the Glasgow Outcome Score (GOS). The study was approved by the local ethics committee. Specimens taken were temporal (n = 11), frontal (n = 8), parietal (n = 4) and cerebellar (n = 1). The incidence of DAI within these specimens was 30% (7 with DAI, 17 without DAI). DAI was verifiable up to 3 days after trauma. There was no correlation between DAI and Marshall classification in CT. The period of coma was longer in subjects with DAI. There was no difference in GOS in the case of a verified DAI. These results enforce the prognostic and neuroradiologic relevance of DAI. However, it is debatable whether the pathomorphologic findings in CT or MRI represent the histological findings of DAI. We suggest a multicentre study for further clarification.

[Comparison of younger and elder patients after multiple trauma]. / Vergleich jüngerer und älterer Unfallopfer nach Mehrfachverletzun.

The purpose of this study was to clarify any influences by age on the outcome after multiple trauma. 520 patients (age > 20 years) were analysed after inclusion in a 3-year national multi-centre study for polytrauma injured subjects. The patients were recruited from 10 German neurosurgical university departments. Criteria for inclusion were head injury and coma at the time of admittance. The elderly were mostly injured by falls, and showed more often intracranial injuries and fractures of the pelvis. The majority of intracranial injuries were characterised by acute subdural haematomas in the elderly and contusions in younger patients. Hence, craniotomy within the first 24 hours was found more often in the elderly. There was a significant trend towards a craniotomy and placement of a pressure catheter in younger patients compared with the elderly. There were significantly lower values for the Glasgow Outcome Scale (GOS) in the elderly, especially in terms of lethality. The depth of coma was a strong predictor for GOS in both groups.

The prognostic reliability of the Glasgow coma score in traumatic brain injuries: evaluation of MRI data.

PURPOSE: To clarify the predictive power of the Glasgow coma score (GCS) after traumatic brain injury (TBI) and in the context of brain stem lesions. METHODS: In 143 patients who had suffered severe TBI, the GCS was correlated to brain damage as visualized by cranial magnetic resonance imaging (MRI). This technique evaluates the damage to the brain stem in particular. The Brussels coma score (BCS) was also used. RESULTS: The GCS was not significantly correlated to brain stem lesions when it was only scored at the time of admission. When MRI was not used later on, the GCS showed a poor ability to predict the outcome. After 24 h, and on the day of MRI screening, the GCS was significantly correlated with two parameters: outcome (the higher the GCS, the better the outcome) and the frequency of patients without injuries to the brainstem in MRI (the higher the GCS, the higher this frequency). These correlations were much more evident when the BCS was used. The prognostic power of the GCS was found to vary over time; for example: a GCS of 3 at admission was associated with a favorable prognosis; a GCS of 4 signified a poor prognosis, irrespective of the time point at which the GCS was scored; and the prognostic power of a GCS of 5 deteriorated from the day of the MRI onwards, whereas the prognostic power of a GCS of 6 or 7 varied little over time. CONCLUSIONS: We only recommend the use of the GCS for prognostic evaluation in a multidimensional model. Study protocols should contain additional brain stem function parameters (BCS, pupil condition, MRI).

[Injuries to the upper cervical medulla in severe brain injuries]. / Verletzungen des oberen zervikalen Myelons beim schweren Schädel-Hirn-Trauma.

BACKGROUND: Cranial magnetic resonance imaging (MRI) was performed in 250 patients who had been unconscious post-trauma for at least 24 hours. The frequency and the characteristics of injuries to the upper cervical myelon were determined. PATIENTS AND METHODS: Between 1996 and 2009, MRI was carried out within 8 days of trauma. RESULTS: No lesions of the upper cervical medulla were found without accompanying damage to the medulla oblongata. Two groups were found to have a lesion in the upper cervical myelon. (i) In 3.2 % of the patients in a state of deep coma MRI revealed lesions in the entire brain stem. These died without waking from coma. (ii) 2 % of the patients were found to have additional damage to the distal medulla oblongata. These victims of high-speed traumas awoke from coma after 2-3 days. They revealed frontal contusions of the brain and traumatic subarachnoidal hemorrhages. Injuries to the bony upper cervical spine and/or the skull base were frequent. Four of them died, one patient survived with severe disabilities. CONCLUSION: Two types of lesions involving the upper cervical myelon could be differentiated, both of which occur only in association with lesions in the medulla oblongata.

Image guided aneurysm surgery in a Brainsuite® ioMRI Miyabi 1.5 T environment.

OBJECTIVE: Current literature only gives sparse account of aneurysm surgery in an intraoperative MRI environment. After installation of a BrainSuite(®) ioMRI Miyabi 1.5 T at our institution the aim of the present preliminary study was to evaluate feasibility, pros and cons of aneurysm surgery in this special setting. MATERIAL AND METHODS: Since February 2009, during a 3 months period we performed elective image guided aneurysm surgery in 4 ACM and 1 ACOM aneurysm (four patients) in this ioMRI setting. The patients' heads were rigidly fixed in the Noras 8-Channel OR Head Coil. Our imaging protocol included MP-RAGE, T2-TSE axial, TOF-MRA and diffusion-/perfusion-imaging immediately before surgery and after clip application. Presurgical 3D-planning was performed using the iPlan®-Software. RESULTS: All five aneurysms were operated without temporary clipping. There were no intra- or postoperative complications. Patient positioning and head fixation with the integrated Noras Head Clamp was feasible, but there were significant limitations particularly with regard to more complex approaches and patient physiognomy. Image quality especially TOF-MRA was good in 4, insufficient in 1 aneurysm. Presurgical planning especially vessel extraction from TOF-MRA was possible but certainly needs significant future improvement. Diffusion- and perfusion weighted examinations yielded good image quality. CONCLUSION: Our limited experience is encouraging so far. Further improvement particularly concerning flexibility of patient positioning and presurgical 3D-planning for vascular procedures is most necessary. As a future perspective image guided aneurysm surgery in an ioMRI-environment may be helpful especially in complex aneurysms and provide neurosurgeons and neuroanaesthesiologists with additional information about cerebral haemodynamics and perfusion pattern in the vascular territory distal to the target vessel.

[Predictive quality of the injury severity score in the systematic use of cranial MRI]. / Prädiktorqualität des Injury Severity Score bei systematischem Einsatz der kraniellen Kernspintomografie.

AIM: The ABBREVIATED INJURY SCORE (AIS) for the head is mostly coded on the basis of cranial computed tomography (CT). It defines, to a large extent, the predictive potency of the INJURY SEVERITY SCORE (ISS). The present study investigates whether the predictive capacity of the ISS can be improved by the systematic use of data from cranial MRI. METHOD: 167 patients, who had been in a coma for at least 24 hours following trauma, underwent an MRI examination within 8 days. All had been found to have an intracranial injury on initial CT. 49 % had also suffered extracranial injuries. The GLASGOW OUTCOME SCALE (GOS) was determined 6 months post trauma. AIS, ISS and GOS values were rated as ordinal measurements. A contingency table was used as the statistical method of analysis, with a significance assumed as p < 0.05 (Chi (2) test). RESULTS: The median ISS based on CT was 16 and did not correlate with the GOS. 63 % of the patients revealed brain stem lesions on MRI. If these were coded with an AIS of 5, the median ISS increased significantly to 29. Thus, the correlation to the GOS was now significant. At ISS scores of 5-9, 18 % of the patients died; at scores of 50-54 the rate of favourable treatment outcomes still amounted to 50 %. Since it is now known that brain stem lesions can also have a favourable prognosis, the AIS coding was modified and adapted to the mortality of the singular types of lesion. Hence the median ISS again decreased to 16. The correlation to the GOS was significant, and the predictive potency of the ISS further improved. The prognostic potency of the REVISED INJURY SEVERITY CLASSIFICATION (RISC) score was improved by use of adapted MRI data. CONCLUSION: If visible brain stem lesions on MRI were coded according to the AIS guidelines, there was a significant increase in the ISS which correlated significantly to the GOS. If the AIS coding was adjusted to the prognostic significance of individual brain stem lesions, there was a further improvement in the prognostic potency of the ISS. The study encourages the inclusion of data obtained from MRI diagnostics in the ISS calculation. There are alternative ways.

[First description of an intradural disc herniation at the C7-T1 level]. / Erstbeschreibung eines intraduralen Bandscheibenvorfalls in Höhe C7/TH1.

41 cases of cervical intradural disc herniation have been reported in the literature, none at the C7-T1 level. We describe a case of myelopathy after a fall. The female patient suffered an ataxia of the legs in combination with unilateral C8 cervicocephalgia and hypaesthesia. Magnetic resonance imaging revealed a space-occupying lesion at C7-T1, so we suspected a tumour. After a dorsolateral approach, an intradural disc herniation was found. Six months after the operation, the patient is free of complaints.

MR imaging and quantification of the movement of the lamina terminalis depending on the CSF dynamics.

BACKGROUND AND PURPOSE: Brain pulsation is a well-known observation in neurosurgery, but methods for its visualization on MR imaging, like phase imaging, do not provide a detailed structural view. We prospectively investigated electrocardiographic (ECG)-gated cine true fast imaging with steady-state precession (FISP) sequence on volunteers to test a sequence for demonstrating brain pulsation and movements of intracranial structures related to CSF dynamics. MATERIALS AND METHODS: Eleven healthy volunteers were investigated with prospectively ECG-gated cine true-FISP in the midsagittal plane. A total of 50 phases were recorded per cardiac cycle and per volunteer. The lamina terminalis was chosen to study the pulsatility of the brain, and the optic recess diameter was chosen for means of objective quantification of the degree of pulsatility. RESULTS: Pulsatile motion of the lamina terminalis was apparent in all volunteers on the cine mode. The mean diameter of the optic recess was 2.5 mm. The greatest change in diameter in 1 volunteer was 1.5 mm. The mean change in diameter was 40% during 1 cardiac cycle. CONCLUSIONS: Cine true-FISP sequence is a well-suited method for investigations of passive movements of the ventricular system. It shows pulsations of the brain as well as passive changes caused by CSF dynamics with high temporal and spatial resolution.

Evaluation of surface and volume rendering in 3D-CT of facial fractures.

OBJECTIVES: Three-dimensional computed tomography (3D-CT) of facial fractures has been reported as beneficial using surface (SR) and volume rendering (VR). There are controversial statements concerning the preferable algorithm. The purpose of this study was to evaluate and compare SR and VR for clinical 3D-CT in facial fractures on an experimental basis. METHODS: Multislice CT was obtained in 22 patients with facial fractures using two data acquisition protocols. Five SR and VR post-processing protocols were applied. Five assessors independently evaluated the quality of visualization of the fracture gap and dislocated fragments as well as the overall image quality using a five-point rating scale. The potential benefit of the 3D-images for radiological diagnosis and presentation was evaluated. The influence of the data acquisition protocol was analysed. RESULTS: SR in general achieved better evaluation scores than VR at corresponding thresholds. Variation of evaluation scores for all criteria was found for SR and VR depending on the segmentation threshold. Apart from the overall image quality no significant influence of the data acquisition technique was found for the evaluated criteria. CONCLUSIONS: SR provided sufficient and time efficient means for 3D-visualization of facial fractures in this study. No diagnostic benefit of VR over SR was found.