[Postoperative imaging of the musculoskeletal system : Clinical aspects]. / Postoperative Bildgebung des muskuloskeletalen Systems : Klinische Aspekte.

BACKGROUND: Postoperative imaging in trauma surgery is an essential part of documenting optimal osteosynthetic care. A precise and goal-oriented analysis with a justifiable indication is essential. The clinical information has a great impact on the quality of imaging. An objective evaluation and structured reporting complete the postoperative imaging procedure. MATERIALS AND METHODS: Conventional x­rays in two planes is the standard of postoperative imaging in musculoskeletal surgery. In specific anatomic structures, additional images may be necessary. The postoperative x­ray is the simplest way to visualize a successful osteosynthesis and combines the most important points of postoperative management. Computed tomography (CT) is mostly used in emergencies, but also in the postoperative management of some elective procedures, including patients with surgery of the spine, hip or to the proximal long bones of the extremities. Furthermore, CT is useful in postoperative imaging of complicated ankle fractures. Magnetic resonance imaging (MRI) plays a modest role in postoperative imaging and is mostly used in musculoskeletal cancer surgery. Ultrasound rather plays a subordinated role in postoperative management, but it is increasingly becoming established as a tool for postoperative quality control. The great advantage is dynamic visualization in real time. CONCLUSION: Postoperative imaging remains challenging, but can detect most issues regarding osteosynthesis, which can be then be treated or monitored. Various imaging modalities are available to make reliable statements on osteosynthetic material, bone and soft tissue.

Lesions of the lateral pterygoid muscle-an overestimated reason for temporomandibular dysfunction: a 3T magnetic resonance imaging study.

The aim of this study was to examine the lateral pterygoid muscle (LPM) parenchyma, myotendinous junction, and tendon in temporomandibular disorder (TMD) patients using 3T magnetic resonance imaging (MRI). Results were compared with findings reported in the literature, in which the LPM has been attributed a major role in triggering TMD. 3T MRI was used for temporomandibular joint (TMJ) imaging. The MRI images of 63 patients were analysed for muscle contracture and atrophy, tendon rupture, signal alterations of the tendon, tendon contrast enhancement, and peritendinous fluid collection. Descriptive statistics and the coefficient estimate method were used for statistical analysis. Focus was placed on the association between LPM tendon pathology and TMJ lesions like osteoarthritis and disc displacement. Severe lesions of the LPM tendon and muscle parenchyma, like rupture or fibrosis, were detected in very few cases. Only moderate signs of tendinosis were found in TMD patients. In contrast, there was a clear correlation between tendon lesions and osteoarthritis or anterior disc displacement. These results indicate the need to discuss and question the role of the LPM and its tendon in TMD. Data suggest that LPM and tendon lesions are part of complex degenerative changes of the TMJ, and it seems less likely that a LPM disorder is causative in TMD.

Intraoperative cell isolation for a cytological assessment of bone resection margins in patients with head and neck cancer.

The intraoperative cytological assessment of bony resection margins (ICAB) is a feasible diagnostic approach to support frozen section for assessment of invasion of margins of soft and hard tissue. However, complex resection margins could challenge both diagnostic approaches. Our objective here was to identify the limitations of intraoperative diagnostic methods for assessing margins. We present an advanced cytological approach to assess complex margins that may solve the problem. Data from 119 patients in whom frozen section was supported by ICAB, were reviewed and the reasons for false results analysed. In 35 patients with squamous cell carcinoma infiltrating bone, specimens (n=100) from the resection margin went through an intraoperative cell isolation process for the cytological assessment of bony margins (ICAB). The results were compared with the histological results of the corresponding margins of bone as a reference. Limitations to the assessment of operative bony margins intraoperatively included an infiltrative histological pattern of growth of the carcinoma, with carcinoma cells disseminated within the cancellous bone, complex and uneven resection margins with soft and bony tissue, inflammation, and signs of previous radiotherapy. Intraoperative cell isolation plus (ICICAB) allowed the microscopic assessment of up to 1cm3 of bony tissue to detect disseminated carcinoma cells within the cancellous bone with a sensitivity of 92.3% (95% CI 74.9% to 99.1%), and a specificity of 100% (95% CI 95.1% to 100%), and positive and negative predictive values of 100% (95% CI 85.8% to 100%) and 97.4% (95%CI 90.8% to 99.7%), respectively. Intraoperative cell isolation is a feasible new technique to support ICAB and frozen section in the assessment of bony and soft tissue margins.

Nontumorous Enlargement of the Internal Auditory Canal: A Risk Factor for Sensorineural Hearing Loss? A High Resolution CT-Study.

PURPOSE: First aim of the study was to define normal shape and diameter of the internal auditory canal (IAC). In the second part the clinical relevance of IAC-enlargement was analyzed, considering also lesions of the subtle structures at the fundus of the internal auditory canal. MATERIALS AND METHODS: 440 high resolution CT-scans of the temporal bone were used for retrospective analysis of the internal auditory canal and its fundus region. RESULTS: The mean value of the IAC diameter in axial and coronal plane was determined. In 20 of 440 patients IAC enlargement was found. In the group with pronounced enlargement (3fold SD) nearly all patients suffered from hearing impairment. In some of them we found structural abnormalities near the IAC fundus in the CSF/perilymph border zone. CONCLUSION: A new CT-based definition of normal shape and diameter of the internal auditory canal is presented. There is some evidence that a pathologic transmission of CSF-pressure in case of IAC-enlargement and/or abnormal fistulous communications could play an important role in the pathophysilogy of hearing loss. KEY POINTS: • New CT-based definition of normal internal auditory canal.• Nearly all patients showing pronounced IAC-enlargement suffer from hearing impairment.• Possible pathomechanism: Transmission of CSF-pressure on the inner ear.

Semicircular canal dehiscence in HR multislice computed tomography: distribution, frequency, and clinical relevance.

The literature about bony defects in the semicircular canal system is highly inconsistent. Therefore, we analyzed a series of 700 high-resolution multislice CT examinations of the temporal bone for semicircular canal dehiscencies. An unselected group of ENT patients with different clinical symptoms and variable age was chosen. We found semicircular canal dehiscence in 9.6% of temporal bones, superior semicircular canal was affected mostly (8%), less common posterior semicircular canal (1.2%); only in 3 cases (0.4%), lateral semicircular canal showed dehiscence. In 60% of SSC dehiscence, we registered bilateral manifestation. The so-called "third mobile window" in semicircular canal dehiscence causes a great variety of clinical symptoms like vertigo, nystagmus, oscillopsies, hearing loss, tinnitus and autophonia. Comparison with anatomic studies shows that CT examination implies the risk of considerable overestimation; this fact emphasizes the important role of clinical and neurophysiological testing.

Monaural tinnitus from a contralateral inferior colliculus hemorrhage.

A 48-year-old man presented with sudden right ear tinnitus and showed no other otoneurologic signs or symptoms. Auditory brainstem response revealed prolonged III-V interpeak latencies from stimulating either ear. MRI revealed a small, circumscribed lesion of the left inferior colliculus, probably from an acute hemorrhage leading to a small cavernous malformation. Circumscribed lesions of the inferior colliculus are rare with no prior reports of contralateral tinnitus.

[Differential diagnosis of neuralgic amyotrophy and vertebral artery dissection]. / Neuralgische Schulteramyotrophie oder Vertebralisdissektion? : Eine abwegige Differenzialdiagnose?

In most cases the definite diagnosis of neuralgic amyotrophy is not possible, so it is based on the typical course of symptoms after other diagnoses have been excluded. We report an otherwise healthy woman who presented with symptoms typical of neuralgic amyotrophy. However we could diagnose a vertebral artery dissection that probably caused the symptoms by compression of the cervical roots. The differential diagnosis of neuralgic amyotrophy and vertebral artery dissection is discussed.

Magnetic resonance imaging and high-resolution computed tomography in the otospongiotic phase of otosclerosis.

Otosclerosis very often leads to severe hearing loss in a chronic progressive manner. In the first phase of the disease, otospongiosis causes an inflammatory osteolytic process in the osseous labyrinthine capsule. In the cases reported here, this osteolytic process was pronounced in the osseous capsule of the cochlea. High-resolution CT and MRI showed the precise localization and stage of this inflammatory-osteolytic process in the petrous bone, while scintigraphy confirmed the diagnosis.

Diagnostic procedures for detection of lymph node metastases in cancer of the larynx.

Squamous cell carcinoma is the most common malignant neoplasm of the larynx. One of the most important influences on prognosis is the presence of metastases to the cervical lymph nodes. Accurate determination of lymph node involvement is therefore a prerequisite for individualized therapy in patients with squamous cell carcinoma of the larynx. Clinical palpation of the neck is not very accurate and the role of imaging techniques such as ultrasound, ultrasound-guided fine needle aspiration cytology, color Doppler ultrasound, computed tomography, magnetic resonance imaging and positron emission tomography is being applied in order to improve upon the results of clinical investigation alone. According to our investigations and review of the literature, the accuracy of computed tomography scanning (84.9%) and magnetic resonance imaging (85%) was superior to palpation (69.7%) and ultrasound (72.7%). Ultrasound-guided fine needle aspiration cytology showed an accuracy of 89% and was in the same range with positron emission tomography (90.5%).