No Fukushima Dai-ichi derived plutonium signal in marine sediments collected 1.5-57km from the reactors.

Based on AMS analysis, it is shown that no Pu signals from the Fukushima accident could be discerned in marine sediments collected 1.5-57km away from the Fukushima Da-ichi power plant (FDNPP), which were clearly influenced by accident-derived radiocesium. The 240Pu/239Pu atom ratios (0.21-0.28) were significantly higher than terrestrial global fallout (0.182 ± 0.005), but still in agreement with pre-FDNPP accident baseline data for Pu in near coastal seawaters influenced by global fallout and long-range transport of Pu from the Pacific Proving Grounds.

Characterization of uranium and plutonium containing particles originating from the nuclear weapons accident in Thule, Greenland, 1968.

To improve long-term radioecological impact assessment for the contaminated ecosystem of Bylot Sound, Greenland, U and Pu containing particles have been characterized with respect to particle size, elemental distribution, morphology and oxidation states. Based on scanning electron microscopy with XRMA, particles ranging from about 20 to 40 microm were isolated. XRMA and mu-XRF mapping demonstrated that U and Pu were homogeneously distributed throughout the particles, indicating that U and Pu have been fused. Furthermore, mu-XANES showed that U and Pu in the particles were present as mixed oxides. U was found to be in oxidation state IV whereas Pu apparently is a mixture of Pu(III) and Pu(IV). As previous assessments are based on PuO2 only, revisions should be made, taking Pu(III) into account.

Plutonium isotope ratios in the Yenisey and Ob estuaries.

Over the past 50 years, nuclear weapons' tests and releases from the nuclear industry have introduced anthropogenic plutonium into the environment. In the Arctic environment, the main source of plutonium is from the atmospheric weapons testing, but previous studies of plutonium in the Kara Sea have shown that, at certain sites, other releases can give rise to enhanced local concentrations. The present paper presents results from determination of plutonium concentrations and isotope ratios in the sediment samples collected during various expeditions to the Kara Sea, the Ob and Yenisey estuaries and their river systems. The data indicated a clear influence from a low 240Pu:239Pu source in surface sediments collected from the Yenisey estuary, whereas plutonium in Ob estuary sediments is dominated by global fallout. The results also show an increase in plutonium concentration (from 0.003 to 11Bq/kg) and a decrease in 240Pu:239Pu isotope ratio (from 0.16 to 0.05) going upstream from the Yenisey estuary towards the nuclear installation at Krashnoyarsk.

[Perilymphatic fistula]. / Perilymfatisk fistel.

BACKGROUND: Perilymphatic fistula is leakage of perilymph from the inner ear to the middle ear. The perilymph surrounds the endolymphatic system in the inner ear (cochlea and the vestibular apparatus) and is most likely a cerebrospinal fluid filtrate. Leakage can occur through the fenestra vestibuli (the oval window), the fenestra cochleae (the round window), or pathological openings in the otic capsule. The cause of perilymphatic fistula can be trauma (barotrauma, head trauma, whiplash injury, iatrogenic trauma during ear surgery or ear syringing), chronic otitis media with cholesteatoma, congenital malformations or idiopathic. MATERIAL AND METHODS: We present 15 patients operated at Haukeland University Hospital from 1980 to 1997. RESULTS: Symptoms and signs are not very consistent, but dizziness and hearing loss are usual. The fistula test has low sensitivity and specificity, and otomicroscopy is not diagnostic. Imaging techniques with CT and MRI are seldom helpful unless in cases of inner ear abnormalities. Surgical exploration of the middle ear can be diagnostic, but even then it may in some cases be difficult to determine if a perilymphatic fistula is present. INTERPRETATION: The treatment of suspected perilymphatic fistula is primarily bed rest with elevated head, and avoidance of straining to facilitate spontaneous closure of a possible fistula. If the symptoms continue, or get worse, surgical exploration is indicated. The results are good regarding dizziness, but more uncertain as far as hearing improvement is concerned. Hearing improvement seems to be negatively correlated with the length of the delay before the fistula is closed.

Cranial dislocation of the mandibular condyle. A case report with an unusual hearing loss.

The case of a 37-year-old woman who suffered a condylar dislocation into the middle cranial fossa is reported. The mechanisms of injury, the problems of clinical diagnosis and the management are discussed.

[Laryngocele]. / Laryngocele.

We report the cases of five patients with laryngocele. In every case the diagnosis was made by computerized tomography. The laryngocele was internal in two cases, external in one case and combined in the rest. One of the patients had bilateral laryngoceles. The value of CT in the diagnosis is stressed, and it is recommended that this radiologic examination (or MRI) should be performed in patients with otherwise unexplained long-standing hoarseness and attacks of stridorous respiration.

Facial nerve paralysis caused by tumor-forming chronic lymphatic leukemia: a case report.

A 60-year-old female with chronic lymphatic leukemia developed a complete facial paralysis. Clinical examination revealed a tumor protruding through the cranial part of the eardrum. A CT scan and biopsy specimens showed a leukemic infiltrate in the middle ear with extension to the facial canal. She was successfully treated with radiotherapy.

Unilateral sensorineural hearing loss in children less than 15 years of age.

1-10 years after the first examination, 56 children below 15 years of age with unilateral sensorineural hearing loss were re-examined with a test-battery consisting of puretone and speech audiometry, stapedius reflex tests, caloric tests, brainstem response audiometry and otoneurological tests. In no case was an acoustic tumour suspected on the basis of the test results. A small progression of the hearing loss occurred in only one ear. In no case did the healthy ears develop hearing loss during the observation period. Diagnostic procedures can in most of such cases be limited to pure-tone audiometry. Follow-up is indicated because some patients require advice considering education and evaluation regarding fitting of a hearing aid.

Heterotopic salivary gland tissue in the upper neck.

Heterotopic salivary gland tissue in the upper neck is believed to be a rare entity, only 3 cases having been reported previously. We present 2 additional cases with a discussion of the possible origin of the tissue. Tumor formation was present in all cases.

Benign fibrous xanthoma of the parotid gland: a case report.

A fibrous xanthoma of the parotid gland is reported, the literature is reviewed with a discussion of the classification of such tumours. The present case is possibly the first report of a typical benign fibrous xanthoma of the parotid gland.