Mucocele formation after frontal sinus obliteration.

BACKGROUND: A possible complication of frontal sinus obliteration with fat is the formation of mucoceles. We studied the prevalence of mucoceles as well as and the need for revision surgery. METHODS: Retrospective case review of forty consecutive patients undergoing frontal sinus obliteration from September 1995 to February 2012 for chronic rhinosinusitis (26), frontal mucocele (12) or frontal osteoma (2) with an average follow up of 80 months (range 15-218). MRI of the paranasal sinuses was performed in all. Outcome measures included MRI signs of mucocele formation in the obliterated frontal sinus, revision surgery, symptom burden. RESULTS: Magnetic resonance imaging (MRI) showed potential postoperative frontal sinus mucoceles in 6/40 patients. In 3 patients (7.5%) a revision operation was performed, revealing mucoceles in two cases. A wait and scan-policy in the other 3 patients confirmed the presence of a mucocele in 1 of these patients. The majority of patients (33/40, 83%) was asymptomatic at the last follow up. CONCLUSION: The prevalence of mucoceles and revision rate in this series was 7.5% (3/40). MRI can improve detection rate and reduce / avoid unnecessary revision surgery after frontal sinus obliteration.

Propranolol as first-line treatment in orbital infantile haemangiomas: a case series.

PURPOSE: To highlight the importance of Magnetic Resonance Imaging (MRI) and the use of propranolol as both a final diagnostic tool and adequate treatment for orbital Infantile Haemangiomas (IHs). METHODS: A retrospective study was conducted using a case series of 5 infants diagnosed with orbital IH. All patients presented with progressive unilateral proptosis and were at high risk of developing amblyopia, some had combined swelling of the eyelid, impaired eye movements or exposure keratopathy. Propranolol was administered in an initial dose of 0.6 mg/kg/day orally divided in three daily doses and increased in 4 days to 2.7 mg/kg/day. MRI was performed in all children. RESULTS: Striking MR characteristics of an IH lesion were seen in each of our 5 cases, including the presence of flow voids, high contrast enhancement, hypo-intense T1W signal, iso- to hyper intense T2W signal, and lobulated appearance. All patients showed a quick clinical response to treatment, resulting in significant reduction in tumour size within a range of 1-3 weeks and almost complete regression of the lesion at the end of the treatment schedule. CONCLUSIONS: Our study adds another 5 cases to the growing body of reports confirming the efficacy and safety - under controlled circumstances - of propranolol therapy in orbital IH management, in which we highlight the use of propranolol as both a final diagnostic tool and as an adequate treatment.

Osteitic bone in recalcitrant chronic rhinosinusitis.

INTRODUCTION: There is increasing interest in the underlying bone of the paranasal sinuses as an important player in recalcitrant Chronic Rhinosinusitis. Close inspection of CT scans often reveals areas of increased bone density and irregular thickening of the sinus walls. This osteitic bone could at least partly explain, why inflammation of the mucosa persists. METHODS: We searched PubMed for all relevant studies, using the following text words: chronic rhinosinusitis, sinusitis, bone, osteitis, osteomyelitis, histology, and treatment. Cited references of retrieved articles were also examined. RESULTS: Background, available data, potential diagnostic options, treatment implications, and suggestions for future research are discussed. CONCLUSION: Osteitis is associated with CRS, however its role in the pathogenic process is not well defined. More research is needed.

Computed radiography versus mobile direct radiography for bedside chest radiographs: impact of dose on image quality and reader agreement.

AIM: To asses the image quality and potential for dose reduction of mobile direct detector (DR) chest radiography as compared with computed radiography (CR) for intensive care unit (ICU) chest radiographs (CXR). METHODS AND MATERIALS: Three groups of age-, weight- and disease-matched ICU patients (n=114 patients; 50 CXR per acquisition technique) underwent clinically indicated bedside CXR obtained with either CR (single read-out powder plates) or mobile DR (GOS-TFT detectors) at identical or 50% reduced dose (DR(50%)). Delineation of anatomic structures and devices used for patient monitoring, overall image quality and disease were scored by four readers. In 12 patients pairs of follow-up CR and DR images were available, and in 15 patients pairs of CR and DR(50%) images were available. In these pairs the overall image quality was also compared side-by-side. RESULTS: Delineation of anatomy in the mediastinum was scored better with DR or DR(50%) than with CR. Devices used for patient monitoring were seen best with DR, with DR(50%) being superior to CR. In the side-by-side comparison, the overall image quality of DR and DR(50%) was rated better than CR in 96% (46/48) and 87% (52/60), respectively. Inter-observer agreement for the assessment of pathology was fair for CR and DR(50%) (κ = 0.33 and κ = 0.39, respectively) and moderate for DR (κ = 0.48). CONCLUSION: Mobile DR units offer better image quality than CR for bedside chest radiography and allow for 50% dose reduction. Inter-observer agreement increases with image quality and is superior with DR, while DR(50%) and CR are comparable.

Image quality of multisection CT of the brain: thickly collimated sequential scanning versus thinly collimated spiral scanning with image combining.

BACKGROUND AND PURPOSE: Routine CT of the brain is traditionally performed with sequential CT. We assessed whether sequential CT can be replaced with thinly collimated multisection spiral CT without loss of image quality. MATERIALS AND METHODS: An observer study was conducted using data from 23 patients who were scanned with both a sequential (collimation, 4 x 5 mm) and a spiral technique (collimation, 4 x 1 mm; pitch, 0.875). Each sequential image was registered with 4 combined spiral CT images at 1.2 mm distance. Two neuroradiologists blindly scored 232 image pairs on 6 aspects: streak artifacts, visualization of brain tissue near skull, visualization of hypoattenuated lesions, gray/white matter differentiation, image noise, and overall image quality. A 5-point scale (range, -2 to 2) was used to score the preferences. The 23 pairs of complete scans were scored likewise. In this case, no registration was performed. RESULTS: Virtually all mean scores were positive (ie, showed a preference for the spiral technique). For the comparison of image pairs, the preferences with respect to streak artifacts (mean score, 1.36), visualization of brain tissue near the skull (mean score, 0.69), and overall image quality (mean score, 0.95) were significant (P < .001). With respect to visualization of hypo-attenuated lesions, image noise, and gray/white matter differentiation (mean scores, 0.18, 0.27, and 0.13), the preferences for spiral CT were not significant. The preferences for the spiral technique were also present at the comparison of the complete scans. CONCLUSION: Thinly collimated multisection spiral CT of the brain with image combining is superior to thickly collimated sequential CT.

Cochlear implant electrode array insertion monitoring with intra-operative 3D rotational X-ray.

During cochlear implantation surgery, we use a mobile C-arm with 3D functionality to acquire per-operative 3D X-ray images. Scanning the multielectrode array is performed once before removal of the stylet and once after full insertion. When dissatisfied with the position of the multielectrode a repositioning is considered which happened occasionally. The major advantage is the extra certainty of the multielectrode array position in the cochlea with low-dose and little extra time. All cochlear implantations are now routinely scanned during surgery.

New detected aneurysms on follow-up screening in patients with previously clipped intracranial aneurysms: comparison with DSA or CTA at the time of SAH.

BACKGROUND AND PURPOSE: Patients with a history of aneurysmal subarachnoid hemorrhage may have aneurysms on screening several years after the hemorrhage. For determining the benefits of follow-up screening, it is important to know whether these aneurysms have developed after the hemorrhage or are visible in retrospect, and if so, whether the size has increased. METHODS: Aneurysms were categorized into de novo aneurysms and aneurysms visible in retrospect (already present) with increased or stable size. We studied aneurysm characteristics for these 3 categories: the relation between aneurysm development or enlargement and duration of follow up and the relation between enlargement and initial size of the aneurysm. RESULTS: In 87 of 495 patients (17.6%), aneurysms were detected; for 51 of these patients with 62 aneurysms, the original catheter or computed tomographic angiogram was available for comparison. Of the 62 aneurysms, 19 were de novo and 43 were visible in retrospect, 10 with increased size and 33 with stable size. De novo aneurysms were mainly < or =5 mm (95%) and located at the middle cerebral artery (63%). For aneurysms visible in retrospect, the most frequent location was the posterior communicating artery (21%). There was no relation between the development of de novo aneurysms or enlargement and the duration of follow-up or between enlargement and the initial size of the aneurysm. CONCLUSIONS: Of aneurysms detected at screening, one third were de novo and two thirds were missed at the time of the initial hemorrhage. One quarter of initially small aneurysms had enlarged during follow-up.

Radiation-induced bilateral optic neuropathy in cancer of the nasopharynx. Case failure analysis and a review of the literature.

CASE REPORT: A case history of unanticipated radiation-induced bilateral optic neuropathy, 18 months after induction chemotherapy and radiation therapy for a locally advanced nasopharyngeal carcinoma, is presented. Retrospective reanalysis of the radiation therapy technique, with emphasis on the doses received by the optic pathway structures, was performed. These re-calculations revealed unexpectedly high doses in the range 79 to 82 Gy (cumulative external and brachytherapy dose) at the level of the optic nerves, which explained the observed radiation injury. CONCLUSION: Routine implementation of computed tomography for 3D dose planning purposes is therefore advocated. Review of the current literature confirms the importance of 3D dose planning in avoiding this complication and high-lights the role of MRI in establishing the diagnosis of radiation-induced optic neuropathy.

Detection of recurrence in patients with clinical stage I nonseminomatous testicular germ cell tumors and consequences for further follow-up: a single-center 10-year experience.

PURPOSE: A wait-and-see policy for patients with stage I nonseminomatous testicular germ cell tumors (NSTGCT) was evaluated in a prospective study. The frequency and time of recurrence, detection of recurrence, and presence of unfavorable prognostic factors were investigated. PATIENTS AND METHODS: During the period 1982 to 1992, 154 patients with stage I NSTGCT (median age, 29 years) underwent orchidectomy and were monitored at follow-up evaluation with physical examinations, alfafetoprotein (AFP) and beta-human choriogonadotropin (hCG) levels, chest x-rays (CXR), and computed tomographic (CT) scans of the abdomen and chest. Multivariate logistic regression analyses were performed to identify prognostic factors. RESULTS: During a median follow-up period of 7 years (range, 2 to 12), recurrence was found in 42 patients (27.3%). All cases of recurrence were detected within 2 years, 90% in the first year after orchidectomy. In 29 patients (69.0%), recurrence was detected in the abdominal lymph nodes. Nine patients (21.4%) had metastases in the retroperitoneum and mediastinum and/or lungs, and four patients (9.6%) had metastases only in the mediastinum or lungs. The majority of recurrences (97.6%) were detected by tumor markers and CT scans. Recurrence was related to the presence of vascular invasion, embryonal carcinoma (E), elevated preoperative hCG level, and absence of mature teratoma (M). Only vascular invasion was an independent risk factor. After polychemotherapy treatment for recurrence, the survival rate for the total group was 98.7%. CONCLUSION: The wait-and-see policy is a reliable method for follow-up monitoring of patients with stage I NSTGCT. Even in patients with unfavorable prognostic factors, it is justified to await the possible appearance of metastases. For the future, it is recommended that CXR be omitted from the schedule, and it might be feasible to discontinue follow-up evaluations after 5 years.

Detection of lymph node metastases of squamous-cell cancer of the head and neck with FDG-PET and MRI.

UNLABELLED: The uptake of 2-deoxy-2-[18F]fluoro-D-glucose (FDG) in neck lymph nodes of twelve patients with a squamous-cell carcinoma of the oral cavity was studied with PET in order to detect and locate lymphogenic metastases. METHODS: The results of FDG-PET imaging were compared with clinical, MRI and histopathologic findings. Standardized uptake values (SUV) were also calculated. RESULTS: A sensitivity of 91% and a specificity of 88% were calculated for FDG-PET. In contrast, a sensitivity of 36% and a specificity of 94% were calculated for MRI. Calculated SUVs for reactive lymph nodes, metastatic lymph nodes and the primary tumor were undifferentiated. CONCLUSION: Using FDG-PET, lymph node metastases of squamous-cell carcinomas of the oral cavity can be visualized with a high sensitivity and specificity. FDG-PET can be an improvement in the evaluation of the neck.

Intramural hematoma of the esophagus: appearance on magnetic resonance imaging.

A 73-yr-old woman on anticoagulant therapy experienced progressive dyspnea and dysphagia due to a large compressing mass in the posterior mediastinum. Because her clinical condition deteriorated rapidly surgery was performed. A large intramural hematoma along the full length of the esophagus with dissection of the muscular layers of the esophagus was found. MRI findings of this case are reported.

[Imaging of the salivary glands. CT and MRI]. / Bildgebung von Speicheldrüsen. CT und MRT.

For the evaluation of diseases of salivary origin, ultrasound and/or sialography is recommended instead of MRI. In cases of salivary tumor, ultrasound may be helpful in delineating superficial tumors. For small tumors no further imaging is needed. When dealing with a large tumor or a tumor in the deep lobe of the parotid gland, MRI is the preferred imaging method. Not only does MRI provide a large variety of soft tissue signal differences, but also the multiplanar facilities are helpful in delineating the extent of the tumor, whether located in the submandibular, sublingual, or parotid gland. Skull base invasion is often well seen by MRI. Subtle changes may be missed and in those cases CT is recommended to exclude or prove destruction of the skull base. For the evaluation of patients presenting with a recurrent pleomorphic adenoma, MRI is recommended in all patients. MRI delineates the extent and number of recurrent tumors better than palpation in most cases. No other imaging technique is as accurate in depicting recurrent pleomorphic adenomas as MRI at present. The use of an intravenous contrast medium remains controversial whether for primary or recurrent disease.

Contributory roles of circulatory glucagon and growth hormone to increased renal haemodynamics in type 1 (insulin-dependent) diabetes mellitus.

The stimulatory effects of growth hormone (GH) and glucagon on renal function are well known, but it is uncertain whether these hormones are involved in the increase in renal function, characteristic of type 1 (insulin-dependent) diabetes mellitus. Therefore, the circulatory levels of GH and glucagon were measured in 10 type 1 diabetic patients with an elevated glomerular filtration rate (GFR > 130 ml min-1 1.73 m-2) and in 20 age and sex matched normofiltering patients (GFR ranging from 90-130 ml min-1 1.73 m-2). In the patients, fasting glomerular filtration rate (GFR) and effective renal plasma flow (ERPF) were determined using 125I-iothalamate and 131I-hippuran, respectively, during near-normoglycaemia. On a separate day, the levels of glucagon and GH were determined in the fasting basal state and after exercise. Multiple regression analysis disclosed that GFR was positively correlated with HbA1 (r2 = 0.18, p < 0.01), glucagon (r2 = 0.14, p < 0.03) as well as exercise-stimulated GH (r2 = 0.10, p < 0.05). ERPF was independently associated with HbA1 (r2 = 0.24, p < 0.005) and glucagon (r2 = 0.18, p < 0.01), whereas renal vascular resistance (RVR) was negatively correlated with stimulated GH (r2 = 0.18, p < 0.02). Kidney volume was positively correlated with HbA1 (r2 = 0.26, p < 0.001) and inversely with RVR (r2 = 0.16, p < 0.01), but not with glucagon or stimulated GH. The present study suggests that circulatory GH and glucagon play a contributory role in the renal haemodynamic changes in type 1 diabetes mellitus.

Malignant parotid tumors: clinical use of MR imaging and histologic correlation.

Magnetic resonance (MR) imaging was performed in 116 patients in whom a parotid mass lesion was clinically suspected. Eighty-six patients had benign disease. The 30 patients in whom a malignant tumor was found were further evaluated. To determine which features are characteristic of malignant parotid tumors, spin-echo T1- and T2-weighted images of malignant lesions in the parotid gland were compared with those of benign disease. In our series, tumor margins, homogeneity, or signal intensity were not discriminative factors to correctly predict benign or malignant disease. Infiltration into deep structures (eg, the parapharyngeal space, muscles, and bone) was observed only in malignant tumors. Infiltration into subcutaneous fat was noticed in malignant as well as in inflammatory disease. No statistically significant correlation was found between tumor grade and MR imaging features in malignant disease. MR imaging is useful in delineating malignant tumors but is unreliable in correctly predicting the histologic nature of a mass lesion in the parotid gland.

MRI or CT in the preoperative diagnosis of bone tumours.

The value of magnetic resonance imaging (MRI) and computed tomography (CT) in the diagnosis of bone tumours was investigated in a prospective study of 25 patients. MRI is superior to CT because it permits multidirectional exposures. Moreover, the tumour can be readily distinguished from the neurovascular structures without injection of contrast medium. MRI gives better contrast than CT, making it possible to study the relationship to the soft tissues, bone marrow and joints more accurately. On the other hand, CT gives a better picture of the destruction of cortical bone. With neither MRI nor CT can the exact tumour length be measured. Neither MRI nor CT permits an exact, reliable diagnosis. Owing to the relatively slow exposure technique in combination with respiratory movements, depiction of the thoracic wall is less satisfactory with MRI than with CT. If both techniques are available, MRI is preferred. In view of the fact that MRI apparatus is still less widely available, it should be borne in mind that CT also allows an adequate investigation of skeletal lesions.

The role of magnetic resonance imaging and computed tomography in the treatment evaluation of retroperitoneal lymph-node metastases of non-seminomatous testicular tumors.

The role of Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) in the treatment evaluation of retroperitoneal lymph-node metastases of non-seminomatous testicular tumors (NSTT) was prospectively studied in 10 consecutive patients before, during and after chemotherapy. The results thus obtained were compared with laparotomy findings before and after chemotherapy, the histology of the primary testicular tumor, and that of retroperitoneal residual lesions after chemotherapy. MRI and CT proved to be equivalent in detection and in determining the anatomical localization and size of the retroperitoneal lymph node metastases. Unlike CT, MRI revealed unmistakable changes in the structure of the retroperitoneal lymph-node metastases during chemotherapy, for which no histological cause was found except in mature teratoma. In mature teratoma a high T2 signal was found within the metastases, corresponding with a high water content. On the basis of tumor consistency and signal intensity in the T1- and T2-weighted images, MRI cannot yet warrant any conclusion about the ultimate effect of chemotherapy.

MRI and CT in the preoperative evaluation of soft-tissue tumors.

The value of MRI and CT in the diagnosis of soft-tissue tumors was investigated in a prospective study of 25 patients. MRI and CT give a true reflection of the tumor dimensions. It is impossible, however, to make a reliable diagnosis with either technique. If both techniques are available, then MRI is to be preferred in view of the better spatial orientation and sharper contrast it offers between the tumor and adjacent structures. If only CT is available, then an adequate image can generally be obtained with this technique too.

[MRI in the diagnosis of tumors of the parotid gland]. / IRM dans le diagnostic des tumeurs de la parotide.

Tumors of the parotid gland are easily depicted with magnetic resonance imaging. Their exact site, and extension in the case of a malignant tumor, are correctly predicted. The histologic nature of the lesion remains to be verified by histologic examination. MRI is invaluable for the detection of recurrent pleomorphic adenomas.

Invasive fibrous thyroiditis (Riedel's struma): a manifestation of multifocal fibrosclerosis? A case report with review of the literature.

A patient is described with Riedel's thyroiditis and invasive fibrous growth in parathyroid, lacrimal glands, and retroperitoneally. It is proposed that Riedel's thyroiditis is not a disease in its own right but a manifestation of a generalized disease of fibrous tissues.