Calcareous termite mounds in South Africa are ancient carbon reservoirs.

Ecosystems that offer carbon sequestration by leaching bicarbonate to groundwater are valuable natural capital. One region that may offer this service is the west coast of South Africa. Over 20 % is covered by soil mounds ("heuweltjies") up to 40 m diameter, 2 m high, inhabited by the southern harvester termite Microhodotermes viator and enriched in soil organic and inorganic carbon and soluble minerals. We aimed to generate radiogenic and stable isotope data for soils and groundwater in a region where these data are absent, to 1) verify the atmosphere-soil-groundwater link, and 2) resolve the timing and pattern of calcite dissolution and water infiltration in the landscape. Results show that soil and groundwater sulfate have the same marine aerosol source. Episodic calcite dissolution in mound centers, which increased during periods of global cooling, has been set against background input of marine aerosols since before the Last Glacial according to radiocarbon (14C) ages. Our data push back soil organic carbon 14C ages of inhabited termite mounds to 13-19 ka (kiloannum, thousand years before present), nest carbonate 14C ages to 33 ka, and mound soil carbonate 14C ages to 34 ka, making these the oldest active termite features ever dated. These ages are consistent with soil organic carbon and carbonate 14C ages of regional, non-mound, coastal petrocalcic horizons formed by accumulation of carbonate leached from their overlying aeolian dune fields. Harvesting activities of termites inject younger organic material around nests >1 m deep, leading to continuous renewal of important soil carbon reservoirs at depth. Termite bioturbation increases the system's ability to dissolve carbonate. The central, bioturbated part of the mounds have greater infiltration depths and greater calcite dissolution, whereas surrounding soils experienced more surface runoff. Calcareous termite mounds offer a mechanism to sequester CO2 through dissolution and leaching of soil carbonate-bicarbonate to groundwater.

Contralateral cochlear implantation prior to vestibular nerve section for 'drop attacks' in the only hearing ear.

BACKGROUND: A dilemma occurs in the treatment of second-sided Ménière's disease in the only hearing ear, particularly in patients with severe symptoms such as 'drop attacks'. This paper describes a patient treated with contralateral cochlear implantation prior to vestibular nerve section of the symptomatic ear. CASE REPORT: A 53-year-old man, with second-sided Ménière's disease and drop attacks in the only serviceable right ear, underwent successful left cochlear implantation 30 years after hearing loss, followed by right vestibular nerve section. The patient achieved control of Ménière's attacks and improved hearing. Although the patient experienced oscillopsia post-operatively, he was satisfied with his improved everyday functioning. CONCLUSION: Patients with severe second-sided Ménière's disease in the only hearing ear are a small but difficult treatment group. In those that are suitable for cochlear implantation in the non-serviceable ear, it is suggested that this be employed prior to surgical treatment of the Ménière's symptoms, even if the implanted ear has had no auditory stimulation for many years.

Ossicular chain reconstruction with a titanium prosthesis.

OBJECTIVE: Ossicular chain damage from chronic ear disease is a significant problem in the Australian population. The ideal ossicular chain reconstruction prosthesis has yet to be defined. This paper examines, for the first time, the use of a titanium prosthesis for ossicular chain reconstruction in Australian patients. STUDY DESIGN: Retrospective chart review. SUBJECTS AND METHODS: All patients undergoing ossicular chain reconstruction with a titanium prosthesis between 1 February 2002 and 31 March 2007. RESULTS: Results showed a low complication rate, with only one extrusion out of 55 cases (1.8 per cent). Successful rehabilitation of conductive hearing loss (i.e. to < or =20 dB air-bone gap) was obtained in 85 per cent of the partial ossicular chain reconstruction group and 77 per cent of the total ossicular chain reconstruction group. Pure tone thresholds improved by an average 18 dB in the partial reconstruction group and 25 dB in the total reconstruction group. CONCLUSION: Titanium is an ideal material for ossicular chain reconstruction due to its ease of insertion, low rate of extrusion and good functional results.

Hyperbaric oxygen for idiopathic sudden sensorineural hearing loss and tinnitus.

BACKGROUND: Idiopathic sudden sensorineural hearing loss (ISSHL) with or without tinnitus is common and presents a health problem with significant effect on quality of life. Hyperbaric oxygen therapy (HBOT) may improve oxygen supply to the inner ear and, it is postulated, may result in an improvement in hearing and/or a reduction in the intensity of tinnitus. OBJECTIVES: To assess the benefits and harms of HBOT for treating ISSHL and/or tinnitus. SEARCH STRATEGY: We initially searched in June 2004 and repeated the search in June 2006. Our search included the Cochrane Ear, Nose and Throat Disorders Group Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 2 2006), MEDLINE (1951 to 2006), EMBASE (1974 to 2006), CINAHL, Database of Randomised Trials in Hyperbaric Medicine (DORCTHIM), AMED, LILACS, KOREAMED, INDMED, National Research Register (NRR), CSA, ISI PROCEEDINGS and ZETOC. SELECTION CRITERIA: Randomised studies comparing the effect on ISSHL and/or tinnitus of therapeutic regimens which include HBOT with those that exclude HBOT. DATA COLLECTION AND ANALYSIS: Three authors independently evaluated the quality of the relevant trials using the validated Oxford-Scale (Jadad 1996) and extracted the data from the included trials. MAIN RESULTS: Six trials contributed to this review (308 subjects). Pooled data from two trials involving 114 patients did not show any significant improvement in the chance of a 50% increase in hearing threshold on Pure Tone Average (PTA) when HBOT was used (relative risk [RR] with HBOT 1.53, 95% CI 0.85 to 2.78, P = 0.16), but did show a significantly increased chance of a 25% increase in PTA (RR 1.39, 95% CI 1.05 to 1.84, P = 0.02). There was a 22% greater chance of improvement with HBOT, and the number needed to treat (NNT) to achieve one extra good outcome was five (95% CI 3 to 20). A single trial involving 50 subjects also suggested significantly more improvement in the mean PTA threshold with HBOT, expressed as a percentage of baseline (WMD 37%, 95% CI 22% to 53%, P < 0.001). The significance of any improvement following HBOT in a subjective rating of tinnitus could not be assessed due to poor reporting. There were no significant improvements in hearing or tinnitus reported in the single study to examine chronic presentation (six months) of ISSHL and/or tinnitus. AUTHORS' CONCLUSIONS: For people with early presentation of ISSHL, the application of HBOT significantly improved hearing loss, but the clinical significance of the level of improvement is not clear. We could not assess the effect of HBOT on tinnitus by pooled data analysis. The routine application of HBOT to these patients cannot be justified from this review. In view of the modest number of patients, methodological shortcomings and poor reporting, this result should be interpreted cautiously, and an appropriately powered trial of high methodological rigour is justified to define those patients (if any) who can be expected to derive most benefit from HBOT. There is no evidence of a beneficial effect of HBOT on chronic presentation of ISSHL and/or tinnitus and we do not recommend use of HBOT for this purpose based on the single study available.

The many faces of facial nerve schwannoma.

BACKGROUND AND PURPOSE: The imaging appearance of facial nerve schwannomas (FNSs) has been described as an enhancing tubular mass (using T1-enhanced MR) within an enlarged facial nerve canal (using CT). The purpose of this study is to identify how often the FNS imaging findings conform to this description and determine whether there are underlying anatomic explanations for the discrepant imaging appearances identified. MATERIALS AND METHODS: The clinical, pathologic, and radiologic records of 24 FNS in 23 patients were retrospectively reviewed. Each FNS was evaluated for location along the facial nerve. The lesions were cataloged by facial nerve segment with the imaging characteristics of each segment described. RESULTS: The average age at time of first imaging was 39 years (age range, 10-70 years). Eighteen (71%) of the 24 FNSs were pathologically confirmed, while the others were determined intraoperatively or diagnostically by the presence of both enlargement of the facial nerve canal and enhancement on contrast-enhanced T1 MR examination. The most common location was in the geniculate fossa (83%), followed by the labyrinthine and tympanic segments of the facial nerve (both 54%). The most common clinical presentation was facial neuropathy (42%). CONCLUSION: The classic description of FNS on enhanced T1 MR is that of a well-circumscribed fusiform enhancing mass along the course of the intratemporal facial nerve with bone algorithm CT showing sharply defined bony canal enlargement. Modern imaging techniques, however, demonstrate the importance of the surrounding anatomic landscape, leading to various imaging appearances. Lesions traversing the labyrinthine segment can demonstrate a dumbbell appearance. When FNSs track along the greater superficial petrosal nerve, they may present as a round mass projecting up into the middle cranial fossa. FNS of the tympanic segment of the facial nerve preferentially pedunculate into the middle ear cavity, clinically presenting as a middle ear mass. When the mastoid segment of the facial nerve is involved, irregular and "invasive" tumor margins seen on MR can be explained on CT as tumor breaking into surrounding mastoid air cells.

Hyperbaric oxygen therapy for idiopathic sudden sensorineural hearing loss and tinnitus: a systematic review of randomized controlled trials.

BACKGROUND: Idiopathic sudden sensorineural hearing loss (ISSHL) and tinnitus are common. Hyperbaric oxygen therapy (HBOT) may improve hearing loss and/or reduce the intensity of tinnitus. METHODS: We performed a systematic search of the literature for randomized controlled trials, and made pooled analyses of pre-determined clinical outcomes where possible. RESULTS: Six trials contributed to this review (304 subjects). Pooled analysis suggested a significantly increased chance of a 25 per cent improvement in hearing threshold on pure tone average with HBOT (relative risk (RR) 1.39, 95 per cent confidence interval (CI) 1.05-1.84, p = 0.02; number-needed-to-treat 5, 95 per cent CI 3-20), but not a 50 per cent increase (RR 1.53, 95 per cent CI 0.85-2.78, p = 0.16). The significance of any improvement in tinnitus following HBOT could not be assessed due to poor reporting. CONCLUSIONS: HBOT improved hearing, but the clinical significance of the level of improvement is not clear. Routine application of HBOT to patients with ISSHL is not justified by this review. More research is needed.

Hyperbaric oxygen for idiopathic sudden sensorineural hearing loss and tinnitus.

BACKGROUND: Idiopathic sudden sensorineural hearing loss (ISSHL) with or without tinnitus is common and presents a health problem with significant effect on quality of life. Hyperbaric oxygen therapy (HBOT) may improve oxygen supply to the inner ear and thereby result in an improvement in hearing and/or a reduction in the intensity of tinnitus. OBJECTIVES: To assess the benefits and harms of HBOT for treating ISSHL and tinnitus. SEARCH STRATEGY: We searched the Cochrane ENT Specialist Register (June 2004), CENTRAL (The Cochrane Library Issue 3, 2004), MEDLINE (1966 to 2004), EMBASE (1974 to 2004), CINAHL (1982 to 2004), DORCTHIM (1996 to 2004), and reference lists of articles. Researchers in the field were contacted. SELECTION CRITERIA: Randomised studies comparing the effect on ISSHL and/or tinnitus of therapeutic regimens which include HBOT with those that exclude HBOT. DATA COLLECTION AND ANALYSIS: Three reviewers independently evaluated the quality of the relevant trials using the validated Jadad 1996 Oxford-Scale and extracted the data from the included trials. MAIN RESULTS: Five trials contributed to this review (254 subjects, 133 receiving HBOT and 120 control). Pooled data from two trials involving 114 patients (45% of the total) suggested there was a trend towards, but no significant increase in, the chance of a 50% increase in hearing threshold on Pure Tone Average (PTA) over four frequencies when HBOT was used (relative risk (RR) for good outcome with HBOT 1.53, 95% confidence interval (CI) 0.85 to 2.78, P = 0.16). The chance of achieving a 25% increase with HBOT was, however, statistically significant (RR 1.39, 95% CI 1.05 to 1.84, P = 0.02). Fifty-six per cent of the control subjects achieved this outcome versus 78% of the HBOT subjects, with the number-needed-to-treat (NNT) to achieve one extra good outcome being 5 (95% CI 3 to 20). A single trial involving 50 subjects (20% of the total) also suggested a significant improvement in the mean PTA threshold expressed as a percentage of baseline (61% improvement with HBOT, 24% with control, WMD 37%, 95% CI 22% to 53%). The effect of HBOT in tinnitus could not be assessed due to poor reporting. There were no significant improvements in hearing or tinnitus reported in the single study to examine the effect of HBOT on a chronic presentation (six months) of ISSHL and/or tinnitus. AUTHORS' CONCLUSIONS: For people with early presentation of ISSHL, the application of HBOT significantly improved hearing loss, but the clinical significance of the level of improvement is not clear. We could not assess the effect of HBOT on tinnitus by pooled analysis. The routine application of HBOT to these patients cannot be justified from this review. In view of the modest number of patients, methodological shortcomings and poor reporting, this result should be interpreted cautiously, and an appropriately powered trial of high methodological rigour is justified to define those patients (if any) who can be expected to derive most benefit from HBOT. There is no evidence of a beneficial effect of HBOT on chronic presentation of ISSHL and/or tinnitus.

Intratemporal facial nerve neuroma: anatomical location and radiological features.

OBJECTIVES: To present the imaging findings and anatomical locations of a series of 88 facial nerve neuromas from two centers over a 30-year period. We describe the salient radiological features of neuromas in each anatomical location and outline the ways in which modern imaging techniques have altered our perception of this entity. STUDY DESIGN: A retrospective review of tumors presenting to two tertiary care referral institutions since 1970. METHODS: The charts and available imaging of patients with the diagnosis of facial neuroma were reviewed. These patients presented to the House Ear Clinic between 1970 and 1994 and to the University of Utah Medical Center (Salt Lake City, UT) between 1986 and August 2000. We examined anatomical location to determine patterns of tumor presentation and compared the findings before and after the era of magnetic resonance imaging (MRI). RESULTS: All segments of the facial nerve were represented. Overall, multiple-segment tumors were almost twice as common (63.6%) as single-segment tumors (36.4%). Before the advent of MRI, all segments of the nerve from the cerebellopontine angle to the tympanic portion were almost equally represented (29.5%-36.3%). After MRI, the geniculate ganglion (68.2%) and labyrinthine portion (52.3%) were by far the most commonly affected areas. Before MRI, there were, on average, 1.89 segments involved per tumor. After MRI, this average number increased to 2.57 segments per tumor. Radiologically, the high-resolution computed tomography and MRI features cannot be generalized. Rather, the imaging features depend on which segments are involved. This is because of the variation in the surrounding anatomical landscape of the facial nerve in its course through the temporal bone. CONCLUSION: The more sensitive imaging provided by newer radiological techniques has altered our perception of facial neuroma. It has provided us with an increased ability to diagnose and fully evaluate this neoplasm preoperatively, allowing improved patient counseling and surgical planning.

Obstructive suprastomal granulation tissue following percutaneous tracheostomy.

Percutaneous dilatational tracheostomy is frequently performed as an alternative to traditional surgical open tracheostomy with many reported benefits. Despite its relative safety and widespread acceptance, complications can be associated with the procedure itself or long-term. We present four cases where there was difficulty with decannulation because of exuberant obstructive granulation tissue. In each case, the percutaneous tracheostomy involved the cricoid cartilage.

[Physiological characteristics of the health status of workers performing physical labor]. / Fizikai dolgozók egészségi állapotának élettani jellemzése.

It was examined the physical fitness of 165 male laborer with a special respect to their physical performance. The research covered other factors, as well such as the somatic and circulatory parameters, the maximal oxygen uptake estimated by Astrand, i.e. the aerobe metabolism, the activity and the fitness of the nervous system, the possible proteinuria following loading, the health condition of the examined persons and also certain other factors concerning their way of life. On the basis of the results, the authors established that with the major share of the examined labourers (nine percent of them) it was impossible to carry out the exercises because of contraindication, and in the case of 46 percent the exercises had to be interrupted because of occurring of certain symptoms and exhaustion. The physical performance was unfavourably affected by the fact that the relative majority of the examined persons are overweight, and the lungs function, especially the MVV-value does not reach the predicted level. Only 32 percent has the optimal body weight, while 20-26 percent is overweight. The MVV-value is under the predicted level in the case of 67-76 percent. The estimated relative aerobe capacity reached 84-86 percent of the predicted value with those whose physical performance is moderate. The authors evaluated the accomplished examinations individually as well and summarized them in records of examination. The records were distributed among the factory medical consultants who applied them effectively in the health provision of the examined persons.

Left ventricular diastolic function in diabetics.

Left ventricular diastolic function was studied in 29 young diabetic patients (aged from 14 to 44 years) without any clinical sign of heart disease. The metabolic state, the presence and the degree of microvascular and neuropathic complications have been established. Age and sex matched 32 healthy subjects served as controls. The parameters of left ventricular diastolic function were determined by means of phonomechanocardiography. By this method in diabetic patients impaired diastolic function of the left ventricle was found. This alteration could be best characterized by the values of normalized relaxation index referring to the isovolumetric relaxation of the left ventricle. A close correlation was found between the microvascular and neuropathic complications and the left ventricular diastolic dysfunction, while no correlation could be demonstrated between the metabolic state and the diastolic cardiac disorder.