No neurochemical evidence of brain injury after blast overpressure by repeated explosions or firing heavy weapons.

BACKGROUND: Psychiatric and neurological symptoms are common among soldiers exposed to blast without suffering a direct head injury. It is not known whether such symptoms are direct consequences of blast overpressure. OBJECTIVE: To examine if repeated detonating explosions or firing if of heavy weapons is associated with neurochemical evidence of brain damage. MATERIALS AND METHODS: Three controlled experimental studies. In the first, army officers were exposed to repeated firing of a FH77B howitzer or a bazooka. Cerebrospinal fluid (CSF) was taken post-exposure to measure biomarkers for brain damage. In the second, officers were exposed for up to 150 blasts by firing a bazooka, and in the third to 100 charges of detonating explosives of 180 dB. Serial serum samples were taken after exposure. Results were compared with a control group consisting of 19 unexposed age-matched healthy volunteers. RESULTS: The CSF biomarkers for neuronal/axonal damage (tau and neurofilament protein), glial cell injury (GFAP and S-100b), blood-brain barrier damage (CSF/serum albumin ratio) and hemorrhages (hemoglobin and bilirubin) and the serum GFAP and S-100b showed normal and stable levels in all exposed officers. DISCUSSION: Repeated exposure to high-impact blast does not result in any neurochemical evidence of brain damage. These findings are of importance for soldiers regularly exposed to high-impact blast when firing artillery shells or other types of heavy weapons.

Hearing development in classical orchestral musicians. A follow-up study.

Using pure tone audiometry in 1995, a hearing reassessment was made in 56 classical musicians who participated in Axelsson & Lindgren's study 16 years earlier, in 1979. This study focuses on hearing development in these classical orchestra musicians, active in Göteborg, Sweden. The aim of the study is to evaluate the risk of progressive hearing loss during work in a classical orchestra. Another aim is to study possible hearing differences in females and males and to compare the high frequency pure-tone average values found in the study with two normal materials. The main findings were that the male, compared to the female musicians, showed a tendency toward a more pronounced, although not significant, hearing reduction in the high frequency region and higher threshold distribution within the 90th percentile than the females. This was found most often in the left ear. The median audiogram for all females showed a notch configuration at 6 kHz, compared to the males who had a high-tone sloping configuration. When comparing high frequency pure-tone average (HFPTA) values with ISO 7029, the females are distributed around the ISO 7029 median and well within the 90th percentile. The average among the males was equal with the median. Comparison with Davis normal population "all the sample, overall occupational group" showed a more even distribution of the HFPTA values around the median for both females and males on both occasions. This follow-up study showed no extended negative progress of the pure-tone hearing threshold values in spite of an additional 16 years of musical noise exposure.

Hearing assessment of classical orchestral musicians.

Pure-tone audiometry was performed on 140 classical orchestral musicians employed at the Gothenburg Symphony Orchestra and the Gothenburg Opera in Sweden. This report is based on the results from hearing threshold measurements, presented as median audiograms according to gender, age group and instrument group. The results did not show severe hearing losses that could be attributed to exposure to musical noise. However, the study reflects the subjects' present hearing ability status and does not give an answer to the question of future hearing dysfunction. Female musicians were shown to have significantly better hearing thresholds in the high-frequency area than did male musicians. Furthermore, the median pure-tone hearing thresholds for the male musicians displayed a notch configuration at 6 kHz in the left ear, similar that of to noise-induced hearing loss. A small, but in general not significant, difference was detected when comparing the median hearing thresholds between each instrument group. Percussion and woodwind players displayed slightly worse hearing thresholds than did other musicians. Players of large string instruments had the best hearing threshold values. When comparing age groups and gender it was noted that the median hearing thresholds were stable and within 20 dB HL up to the age group of 40-49 years for both females and males.

Spontaneous subcapsular or perirenal haemorrhage caused by renal tumours. A urological emergency.

OBJECTIVE: Spontaneous perirenal haemorrhage is a rare abdominal emergency most commonly caused by solid renal tumours. The aim of this study was to evaluate the efficacy of different diagnostic methods and treatment modalities. MATERIAL AND METHODS: A total of 9 patients (5 women and 4 men) with spontaneous subcapsular or perirenal haemorrhage caused by renal tumours were treated at two Finnish central hospitals over a period of 20 years. RESULTS AND CONCLUSIONS: All the patients presented with flank pain, often severe and associated with a palpable mass and a reduced haemoglobin concentration. Ultrasonography was abnormal in all cases where it was used, but was able to show the tumour and haemorrhage correctly in only one case (13%). Computed tomography had a sensitivity of 71%. Seven patients underwent extrafascial nephrectomy (5 renal cell cancers, 1 malignant oncocytoma and 1 angiomyolipoma) and two with known tuberous sclerosis and bilateral renal angiomyolipomas were treated by superselective embolization. As these few cases were all individual and were collected over a long period of time, general statements about diagnosis and treatment must be approached critically. It may be concluded, however, that spontaneous perirenal haemorrhage is often a surgical emergency necessitating great efforts in terms of diagnosis and treatment. Computed tomography should be performed on all patients nowadays. If the bleeding is caused by a malignant tumour, extrafascial nephrectomy is the treatment of choice. For those with benign tumours selective embolization should be used.

Comparison of early deflation rate of detachable latex and silicone balloons and observations on persistent varicocele.

PURPOSE: To determine the frequency of and time until spontaneous deflation of detachable embolization balloons made of different materials and the correlation between persisting or recurrent varicocele and the spontaneous deflation of the balloons. MATERIALS AND METHODS: Forty-five patients with clinically detected left-sided varicocele underwent embolization with 78 silicone and 22 latex balloons. The minimum follow-up time was 3 months and the follow-up consisted of clinical examination, color duplex ultrasonography, and plain radiography of the balloons. Those patients who were suspected of having recurrent varicoceles underwent control venography to assess the internal spermatic vein. RESULTS: All of the latex balloons and 10% of the silicone balloons deflated spontaneously during the follow-up. The average time until deflation was 5.1 months for latex and 9.9 months for silicone balloons. Persistence of varicocele, attributed to perfusion through a previously occluded portion of the internal spermatic vein, occurred in two of 11 (18%) recurrences. Nine of 11 (72%) recurrences were due to bypassing collaterals past the site of detachable balloon placement. CONCLUSIONS: Latex balloons seem to predispose more to persisting/recurrent varicocele than silicone balloons. Early deflation of the balloons explained two (18%) of the 11 persisting or recurrent varicoceles. A combination of a sclerosing agent with balloon embolization of the internal spermatic vein is recommended.

Temporary threshold shift induced by music.

Three groups of young people, in all 10 males and 11 females, with different music listening habits listened to their own choice of music from a portable cassette player for one hour. The sound pressure level from the music was measured with a probe-provided miniature microphone in the external auditory canal close to the tympanic membrane. The temporary threshold shift induced by the music, as well as by 1/3-octave band noise, was registered with Békéky audiometry. The females had significantly more temporary threshold shift than the males after noise-exposure. Most subjects had only discrete temporary threshold shifts after one hour of listening to music, in spite of 91-97 dB listening levels. There were no significant differences in listening levels or music-induced threshold shifts between genders, although such differences were found between groups with different listening habits.

Is routine ipsilateral adrenalectomy during radical nephrectomy harmful for the patient?

To investigate the effects of unilateral adrenalectomy on the postoperative course and laboratory parameters, 40 patients with a renal tumour were randomized either to undergo (n = 20) or not to undergo (n = 20) ipsilateral adrenalectomy. Adrenal hormone (cortisol, epinephrine, norepinephrine and aldosterone), adrenocorticotropic hormone, electrolyte, creatinine, growth hormone, glucose, insulin and free fatty acid concentrations were measured preoperatively and postoperatively. Cortisol and epinephrine concentrations were elevated immediately after the operation but returned to preoperative levels within the first 2 postoperative days. There were no significant differences between the adrenalectomy and non-adrenalectomy groups, except that the cortisol concentration was higher in the latter in the afternoon of the day of surgery. The conclusion is that no long-term shortage of adrenal hormones is caused by unilateral adrenalectomy. Other metabolic and endocrine responses were identical in the groups. Thus ipsilateral adrenalectomy does not seem to be harmful to the patient and the need for it must be resolved on the basis of local tumour factors.

The effect of low level acoustic stimulation on susceptibility to noise in blue- and brown-eyed young human subjects.

OBJECTIVE: The aim of this study was to investigate the influence of pigmentation on the reduction in temporary noise-induced threshold shift (TTS) due to low level acoustic stimulation (LLAS). A pigmentation-dependent LLAS effect on TTS could be interpreted as a strial melanocyte involvement in LLAS. It could not be explained by cochlear sensorineural structure changes only. DESIGN: Teenagers were classified according to eye color (n = 6 + 6) and exposed to music at 70 dBA 6 h per day for 9 days (LLAS). TTS was measured before, during, and after the LLAS period. RESULTS: It was shown that LLAS reduced TTS significantly more in blue-eyed than in brown-eyed subjects. The difference in TTS remained for at least 1 wk after the cessation of LLAS. CONCLUSIONS: It is suggested that the observed difference in LLAS effect is due to strial melanocyte differences in free radical defense. It is also possible that other cochlear antioxidant enzyme systems, responsible for inactivation of harmful oxygen radicals and simultaneously involved in melanin synthesis such as the thioredoxin reductase/thioredoxin electron transfer system are activated.

Experiences with mobile extracorporeal shock wave lithotriptors in northern Finland.

A total of 285 renal units in 248 patients received 424 extracorporeal shock wave lithotripsy (ESWL) treatments with mobile lithotriptors for renal and ureteric stones at Oulu University Hospital. Treatments were given approximately once a month (1-2 days) with 7-10 treatments per day. The overall success at 1-3 months was 88% (74% stone-free). Success with single renal stones was 88% (70% stone-free), that with multiple renal stones 78% (62% stone-free) and that with ureteric stones 93% (89% stone-free). Retrograde manipulation appeared to be a safe and effective treatment for patients with obstructing ureteric stones obliged to wait for the next treatment session. The most serious complication was one perirenal haematoma requiring transfusion. The results compare favourably with those achieved with fixed lithotriptors and prove that mobile lithotriptors are suitable for small centres.

The relationship between sound transfer functions and hearing levels.

The effects of individuals differences in sound transfer function (STF) from free sound field to the tympanic membrane on hearing levels was studied in the right and left ears of 55 young male and 45 young female subjects. Furthermore, canal volumes and lengths have been recorded. STFs were measured in 1/3-octave bands using a miniature microphone and an attached probe. STF measurements were performed in the 0.5-16 kHz frequency range. Audiograms were registered with linear frequency sweep from 0.25 to 8 kHz. Transfer function spectra and magnitudes as well as ear canal dimensions were compared to hearing levels. There was a significant relationship between the dimensions of the ear canal and hearing levels. Large, compared to small, ear canal volumes resulted in a shift of STFs towards lower frequencies. STF spectra and magnitudes had a significant effect on hearing levels. Subject with low-frequency-dominated STFs have higher hearing thresholds than subjects with lower magnitude STFs.

Voiding dysfunction and urodynamic findings in patients with lumbar spinal stenosis and the effect of decompressive laminectomy.

Eighteen consecutive patients (12 men and 6 women, mean age 55) with clinically and radiologically verified lumbar spinal stenosis underwent urodynamic examinations before decompressive laminectomy (n = 16) and 15 afterwards. Twelve of the patients (67%) had symptoms of voiding dysfunction preoperatively but urodynamic findings were normal in most cases only one patient showing detrusor hyperreflexia and one obstruction. Three patients reported an improvement in voiding postoperatively. Three patients showed obstructive voiding postoperatively, one undergoing TURP with a good outcome. One patient developed detrusor areflexia after the operation, with difficulties in bladder emptying. The only statistically significant changes in urodynamic parameters were rises in the maximum urethral pressure and urethral closure pressure. When considering the radicular symptoms and back pains the overall outcome was assessed as excellent or good in 6 cases, 6 had a fair outcome and 4 poor. Decompressive laminectomy gives acceptable results but the effects on bladder and urethral function remain controversial and unexpected. Electrophysiological investigations are needed for more detailed analysis of these cases.

The relationship between sound transfer functions from free sound field to the eardrum and temporary threshold shift.

Three groups of 12 subjects were utilized for an experiment in which the temporary threshold shift due to a free-field exposure was measured and compared to the sound transfer functions from free-sound field to the subjects' eardrums. Subject selection was based upon their sound transfer functions and the requirement of normal hearing. The subjects were assigned to one of three groups depending on their dominantly sound transfer function frequency: Low, middle, or high. A probe tube with a miniature microphone was used for the measurement of the sound transfer functions in 1/3-oct bands. The measurements were performed in frequency bands from 0.2 to 20 kHz with one direction of sound incidence: 0 degree azimuth and 0 degree elevation. The subjects were exposed twice to a 2-kHz and twice to a 4-kHz narrow-band noise monotonically on four different occasions. Pre- and postexposure sweep Békésy audiograms were recorded and the temporary threshold shift calculated as the difference between the two. The averaged temporary threshold shifts differed significantly among groups.

Sonographic follow-up of ethanolamine oleate sclerotherapy for hydrocele.

Sclerotherapy has gained increasing popularity during the last few years as a treatment for hydrocele. Little is known of the natural course of intrascrotal changes, however, nor of their timetable after therapy. In the present trial scrotal ultrasonography was performed before the sclerotherapy and during the follow-up examination in the case of 70 symptomatic consecutive outpatients ranging in age from 19 to 85 years (mean, 58 years) with 71 hydroceles treated by ethanolamine oleate sclerotherapy. Posttreatment sonographic findings typically included heterogeneously echogenic extratesticular masses, cystic areas with peritesticular hyperechoic lines, and a thickened scrotal wall. All the lesions showed improvement. Sonography proved to be useful for differentiating hydroceles from spermatoceles and for evaluating the need for a renewed treatment during follow-up. Ethanolamine oleate was effective as a sclerosant, as 86% of cases were cured or significantly improved. Complications were mild and uncommon, and no intratesticular or epididymal changes were observed. Ethanolamine oleate sclerotherapy can be recommended as a treatment of choice for hydrocele.

Miniature microphone probe tube measurements in the external auditory canal.

The use of a miniature microphone probe tube for sound-pressure level measurements in the outer earcanal was studied in four experiments. The main reason was to evaluate this method for clinical applications and for measurements of hearing protector attenuation. All measurements were registered in 1/3-oct bands. The dynamic range, frequency response of the microphone system, the insertion loss of the probe tube walls, and the influence of the probe tube in the ear canal on the sound-pressure level were examined. The first experiment attempted to determine an optimal placement of the probe tube in the earcanal. Sound-pressure levels resulting from a known free-field sound stimulus were measured at 12 different positions in the earcanal of human subjects. The results indicated that the position which is least sensitive for small movements of the probe tube on the measure was within 1 to 3 mm of the tympanic membrane. In a second experiment the changes in sound transfer function to the tympanic membrane caused by the microphone itself, when positioned just outside the ear canal entrance, were studied for 72 angles of sound incidences in ten subjects. A few minor but significant changes were observed with the microphone in this position. In a third experiment, sound transfer functions were measured from free sound field to the tympanic membrane in 19 subjects. The measurements were performed in 1/3-oct frequency bands (0.2 to 20 kHz) with sound incidences from 24 azimuthal positions and for each of these, three different elevations. The inter- and intrasubject-variability are analyzed and discussed. Finally, the reliability of probe tube microphone measurements was evaluated by repeated measurements of the sound transfer function, five times in ten subjects with the sound incidence from one position. The results indicated very small variations between repeated measurements.

Treatment of penile incarceration by the string method: 2 case reports.

We report 2 cases of penile incarceration in a 10-year-old boy and a 40-year-old man. In both cases the penis was encircled by a metallic object. The string method described was successful, rapid, atraumatic and simple to use.

Ultrasound follow-up of ethanolamine oleate sclerotherapy for spermatoceles.

Although sclerotherapy as a treatment for hydroceles has gained in popularity during the last few years, there is no consensus on whether it can also be adopted for the treatment of spermatoceles. We examine here the efficacy and safety of ethanolamine oleate sclerotherapy in cases of spermatocele using ultrasound (US) before treatment and during follow-up. Thirty-seven consecutive outpatients aged 36-84 years (mean 61) with symptoms of 40 spermatoceles (1-3 chambers) treated by sclerotherapy were included in the series. It is concluded that US allows multilocular spermatoceles to be differentiated from hydroceles. Post-treatment US findings are typical, including heteroechoic masses with cystic areas extratesticularly, hyperechoic lines peritesticularly (thickened tunicas) and a thickened scrotal wall. All lesions are reversible, however. US is helpful when assessing the need for resclerotherapy. Ethanolamine oleate proved to be effective as a sclerosant, as 83% of the cases were cured or became significantly better. Complications were few and there were no changes in the epididymis. Ethanolamine oleate sclerotherapy can be recommended as an alternative treatment to surgery, especially in older patients with spermatoceles consisting of 1-3 chambers.

Diagnostic and therapeutic aspects of adenocarcinoma of the urinary bladder.

Twenty cases of adenocarcinoma of the urinary bladder were diagnosed and treated at Oulu University Hospital between 1978 and 1991, comprising nine primary adenocarcinomas (three urachal and six non-urachal) and 11 of extravesical origin (six from the colon, four from the prostate and one from the perineal skin). The prognosis for primary adenocarcinoma after radical surgery was relatively favourable during a follow-up of mean 54 months, but extravesical origin carried a high mortality rate. The diagnostic and therapeutic aspects are discussed.

The sound world of the child. The relationship between daily activities and hearing acuity.

A group of 50 first, fourth and sixth grade children provided diaries of their activities each hour of the day for 12 consecutive weeks. These activities were correlated with their auditory thresholds assessed at two different times during the behavioral recording period. The results indicated that these schoolchildren experience relatively little noise exposure during their normal daily activities. Further, the incidence of noisy activities was not closely related to hearing thresholds. Other behaviors that are relatively quiet, such as watching television, however, were predictive of higher auditory thresholds.

Intrascrotal adenomatoid tumors and their ultrasound findings.

Adenomatoid tumors are regarded as uncommon neoplasms of the paratesticular tissues, probably of mesothelial origin, and the majority of cases reported have involved the epididymis. Ultrasonography is the method of choice for imaging scrotal pathology, but there are very few data on ultrasound findings in cases of adenomatoid tumors. We report our experience and ultrasound findings regarding 8 intrascrotal adenomatoid tumors--3 cases of a testicular tunica albuginea tumor and 5 cases of epididymal origin. Ultrasonography is recommended as the preoperative imaging method for excluding the possibility of a cystic lesion and for determining the location of the tumor. Local excision is regarded as the treatment of choice. The clinical course of all these tumors was benign, without recurrences.