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T M Jørgensen

Publications and source records attributed to T M Jørgensen.

At least 19 recordsLinked to original sources
PubMed2005

Enhanced optical coherence tomography imaging by multiple scan averaging.

AIMS: To describe a method for computerised alignment and averaging of sequences in optical coherence tomography (OCT) B-scans and to present selected clinical observations based on the resulting improvement in retinal imaging. METHODS: A methodological study and retrospective investigation of selected cases. Five human subjects were included, one healthy subject, two patients with central serous chorioretinopathy, one patient with branch retinal vein occlusion, and one patient with cilioretinal artery pseudo-occlusion. Based on computerised alignment of sets of B-scans obtained at identical retinal locations, average OCT images were produced and displayed in false colour or grayscale. These enhanced tomograms were compared with other morphological and functional characteristics. RESULTS: Improved retinal imaging enabled assignment of the OCT image to retinal anatomy particularly at the outer layer of the photoreceptors and the retinal pigment epithelium, both in the healthy eye and in pathology. Identification of both post-oedematous structural disorganisation as well as post-ischaemic attenuation of the inner retina was superior to standard OCT images. CONCLUSIONS: Averaging of multiple OCT B-scans enhances the quality of retinal imaging sufficiently to reveal new details of retinal pathophysiology. Using the technique on OCT3 scans enables visualisation of details comparable with the results obtained using ultra high resolution OCT.

Adult↗
PubMed2004

Effects of high frequency deep brain stimulation on urine storage and voiding function in conscious minipigs.

AIMS: Suprapontine neural integration during the storage phase is decisive for the timing of voiding. Neurological disorders like Parkinson's disease are thus frequently complicated by bladder dysfunction. The aim of the present study was to investigate the effect of high frequency deep brain stimulation on the urine storage and voiding function in conscious Parkinsonian minipigs. MATERIALS AND METHODS: Five Goettingen minipigs had a Parkinsonism-like state induced by intoxication with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). An electrode for chronic stimulation was placed unilaterally in the subthalamic nucleus. The effect of stimulation was determined by the outcome of transurethral cystometries performed with the stimulation in on- and off-mode. RESULTS: Of 20 planned cystometry-sessions 18 were completed. Six incomplete voidings occurred in stimulation on-mode and five in off-mode. Interruption of the stimulation for 2 days was followed by a significant increase in pressure rise on filling to cystometric capacity, from 7 to 21 cmH(2)O (P = 0.005), and an insignificant reduction in cystometric capacity from 30 to 26 ml/kg bodywt. (P = 0.370), leading to a significant decrease in bladder compliance from 124 to 34 ml/cmH(2)O (P = 0.013). CONCLUSIONS: Transurethral cystometry was a feasible examination technique in pigs. The findings demonstrate that high frequency deep brain stimulation changes the bladder characteristics in the storage phase. Since bladder pressure and capacity responded differently to interruption of stimulation distinct neural mechanisms must be involved in the modulation of sensory information on bladder tension and stretch.

Animals↗
PubMed2004

Twenty-four-hour ambulatory urodynamics in healthy young men.

OBJECTIVE: To describe normal natural fill urodynamics in young men during normal and increased fluid intake. MATERIAL AND METHODS: Thirty healthy males aged 21-32 years volunteered for an ambulatory urodynamic 24 h investigation with a suprapubic catheter. The recorded micturition data were: frequency (f), voided volume (VV), voiding time, maximal flow rate (Qmax) and time to Qmax. The number of sensed and not-sensed bladder contractions, duration and time in relation to voiding were also recorded. During the recording day subjects were randomized to normal (30 ml/kg body weight per day) or larger (60 ml/kg body weight per day) fluid intake. RESULTS: As expected there was a larger urine production and an increased voiding frequency in the fluid-loaded group (p<0.0001). The detrusor pressure (Pdet) Qmax was significantly higher in the fluid-loaded group (73 cmH2O, range 57-94) than in the normal fluid intake group (60 cmH2O, range 45-86) (p=0.003). No other urodynamic data differed significantly between the two groups. When comparing the ambulatory urodynamic data with previously obtained home flowmetry recordings from the same volunteers differences were only found in voiding frequency. The majority of participants had detrusor contractions, felt and unfelt, during the filling phase. Three types of detrusor activity during voiding phase could be described: type 1, with one micturition contraction, type 2, with several small contractions before micturition, and type 3, with large prolonged contractions leading to micturition. CONCLUSIONS: Ambulatory urodynamics in normal young men showed a large interindividual variation. Bladder contractions during filling were frequently recorded, and premicturition contractions were consistently found. The data found in this study were similar to previous home flow recordings in the same group.

Adult↗
PubMed2004

Male fetal pig lower urinary tract function. Part II: free voiding pattern close to term and in the newborn.

PURPOSE: We assessed the development of natural voiding function late in gestation and in the immediate postnatal period in a porcine model. MATERIALS AND METHODS: The study comprised 7 male fetal minipigs (median age 94 days, 0.88 gestation) and 7 male newborn pigs. In all pigs an ultrasonic probe was placed around the subcutaneous urethra and pressure catheters were placed in the bladder and rectum and in the amnionic cavity in the fetal pigs. The catheters were connected to pressure transducers as the flow probe was connected to a flow meter, and the recordings were sampled at a rate of 10 Hz on a personal computer. RESULTS: The newborns had a median voiding frequency of 3.3 times per hour while the fetuses voided a median of 5.9 times per hour (p = 0.16). Both groups voided with a staccato flow at a frequency of 1 to 2 Hz, indicating voiding dyscoordination between the detrusor and urethra. Maximum flow rate increased from median 4.4 ml per minute (range 2.0 to 8.8) in the fetal group to median 10.9 (5.4 to 18.3) in the newborns (p = 0.07). While the minimum opening pressure remained unchanged (median 7.0 cm H2O, range 5.7 to 13.0) vs median 7.6, (range 7.7 to 14.0, p = 0.57) the detrusor pressure at maximum flow decreased from median 22.4 cm H2O (range 16.6 to 39.0) in the fetal pigs to 12.1 cm H2O (8.3 to 22.3) in the newborns. CONCLUSIONS: Fetal and newborn pigs have dyscordinated voiding with a staccato flow. While the urethral opening pressure appears to be unchanged, the detrusor pressure at maximum flow decreases during the last period of gestation, indicating decreased urethral resistance. These findings are in accordance with observations made in human infants.

Animals↗
PubMed2002

Severe partial ureteric obstruction in newborn rats can produce renal dysplasia.

OBJECTIVE: To investigate whether partial unilateral ureteric obstruction (PUUO) produces renal dysplasia in newborn rats. MATERIALS AND METHODS: Left mild (in 31) or severe (in 34) PUUO was induced in 2-day-old rats by embedding a quarter or two-thirds of the ureter into the psoas muscles, respectively. Sham-operated control rats (36) were assessed in parallel. Kidney morphology, renal parenchymal weight and histology were examined 24 weeks and 30 months afterward. RESULTS: There was significant pelvic dilatation in all obstructed kidneys; four kidneys were dysplastic in those severely obstructed, with a significant decrease in renal volume. There were three dysplastic kidneys after 6 months and one at 30 months. The in vitro dysplastic kidney weight was 36% of the control kidneys. Microscopy showed primitive glomerular and tubular structures, with renal parenchymal developmental disorganization and marked fibrosis. The glomeruli, tubules and collecting ducts were deficient in number and had often undergone cystic changes. Columnar tubular epithelium and peritubular mesenchymal collars were present. There was no renal dysplasia in the mildly obstructed and sham-operated rats. The parenchymal weight of the kidneys contralateral to the dysplastic kidneys was significantly higher than in the controls (P < 0.001). CONCLUSIONS: Severe PUUO can produce renal dysplasia in newborn rats. However, only 12% with severe obstruction had renal dysplasia, indicating that the cause of renal dysplasia might also be related to other factors.

Animals↗
PubMed2002

Bladder and urethral responses to pelvic nerve stimulation in the pig.

OBJECTIVE: The aim of our study of the pig was to investigate the responses of smooth muscle of the bladder and the urethral sphincter to preganglionic parasympathetic stimulation, and to assess the effect on the lower urinary tract of IV administration of alpha,beta-methylene-ATP. MATERIALS AND METHODS: In seven anaesthetised female pigs, the responses to repeated 20 s pelvic nerve stimulations before and after IV administration of 0.02 mg/kg alpha-beta-methylene-ATP, and the responses to the drug itself, were recorded in the bladder and the urethra separately. RESULTS: In the urethral high-pressure zone, pre-stimulation pressure was a mean of 61+/-11 cmH2O. During pelvic nerve stimulation, urethral pressure declined by 48+/-9 cmH2O, while the bladder pressure increased to 30+/-18 cmH2O. The rate of pressure changes during the first 3 s of stimulation (initiation of voiding) was larger in the urethra than in the bladder (urethral pressure decrease: 13.0+/-3.1 cmH2O/s, bladder pressure increase: 3.2+/-2.5 cmH2O/s). Administration of alpha,beta-methylene-ATP was followed by a significant but temporary enlargement in the bladder response to pelvic nerve stimulation to 36+/-20 cmH2O, p = 0.028, n = 7, but no change in urethral response. CONCLUSIONS: At least 80% of the urethral pre-stimulation pressure was exerted by the smooth muscle. The synergic activation of the detrusor and the urethral smooth muscle in response to preganglionic parasympathetic nerve stimulation was controlled by the peripheral nerves or by the neuromuscular transmission. Administration of alpha,beta-methylene-ATP increased the bladder response to pelvic nerve stimulation without changing the urethral response.

Adenosine Triphosphate↗
PubMed2001

Male fetal pig lower urinary tract function in mid second and early third trimester of gestation.

PURPOSE: Routine use of ultrasound during pregnancy has emphasized the need for greater knowledge about normal and abnormal voiding function during fetal live. We describe the developmental changes in lower urinary tract function from the middle of the second to the early third trimester of gestation. MATERIALS AND METHODS: The study included 22 male fetal pigs of 13 pregnant Goettingen minipigs (gestational period 111 to 115 days) with 11 fetuses in the middle of the second (median 61.5 days, 0.55 of term) and 11 fetuses in the beginning of the third trimester of gestation (median 80 days, 0.72 of term). With the sow under isoflurane anesthesia catheters were placed in the bladder, rectum and amniotic cavity of the fetuses, and a flow probe was placed around the distal urethra. After the sow was at light sleep urethral flow, amniotic pressure, abdominal pressure and bladder pressure were recorded a median of 241 minutes. RESULTS: The recordings of 14 fetuses were evaluable. In the middle of the second trimester the fetuses showed an almost constant dribbling with a median flow of 0.2 ml. per minute and a median of 4 concomitant bladder contractions per minute of median 3.5 cm. H2O (detrusor pressure). At the beginning of the third trimester the fetuses had periods of staccato flow (median 0.2 ml. per minute, staccato frequency 1 to 2 Hz.) on top of contractions (median 4 contractions per minute, median detrusor pressure 5.5 cm. H2O) with no flow between voidings. CONCLUSIONS: Development of storage and voiding function in male pigs occurs between the mid-second and early third trimester of gestation, together with emergence of striated sphincter bursting activity, which interrupts flow in the urethra during the voiding phase.

Animals↗
PubMed2001

Renal function outcome in unilateral hydronephrosis in newborn pigs. II. Function and volume of contralateral kidneys.

PURPOSE: We evaluated the compensatory response of contralateral kidney growth and function in pigs with unilateral hydronephrosis. MATERIALS AND METHODS: Unilateral partial ureteral obstruction causing severe hydronephrosis was induced at age 2 days in 12 piglets, while 10 underwent sham operation. At ages 4, 12 and 24 weeks single kidney function was assessed using 99mtechnetium diethylenetriaminepentaacetic acid differential uptake on renography combined with the glomerular filtration rate estimated from the plasma clearance of 99mtechnetium diethylenetriaminepentaacetic acid. Kidney size was measured in parallel by magnetic resonance imaging. RESULTS: At 4 weeks the glomerular filtration rate and volume of the contralateral kidneys did not differ from those in controls, although obstructed kidney function was significantly decreased. At 12 weeks the mean glomerular filtration rate plus or minus standard error of mean of the contralateral kidneys significantly increased to 1.60 +/- 0.11 versus 1.33 +/- 0.11 ml. per minute per kg. (p <0. 05), whereas kidney volume did not differ from that in sham operated controls. At 24 weeks the glomerular filtration rate and volume of the contralateral kidneys did not differ from those in controls. Glomerular filtration rate and volume of the contralateral kidneys did not correlate at 4 weeks but they correlated at 12 and 24 weeks (r = 0.94 and 0.89, respectively). CONCLUSIONS: Initially kidneys contralateral to obstructed kidneys with decreased function had no increased growth or function. Furthermore, function and volume of the contralateral kidneys were not associated at the early age. Thus, the results of our study imply that determining the size (growth) or function of the contralateral kidney at an early age does not predict function decrease in a partially obstructed kidney in this pig model.

Animals↗
PubMed2001

Partial unilateral ureteropelvic junction obstruction induced in 2-week-old piglets.

PURPOSE: We examined effects on kidney function and morphology of a partial ureteropelvic junction obstruction induced late in the postnatal nephrogenesis period of the pig. We compared the results to a similar study on pigs with obstruction induced early in the nephrogenesis period. MATERIALS AND METHODS: A total of 20 14-day-old pigs were included in the study. Fifteen animals were randomized to partial unilateral obstruction and 5 were sham operated. Kidney function and morphology were analyzed regarding glomerular filtration rate, renographic functional share and total kidney volume at the age of 4, 12 and 24 weeks. RESULTS: At age 4 weeks hydronephrosis was found in all obstructed kidneys included in the study. Four obstructed kidneys had renographic functional share 40% or greater and 1 deteriorated to less than 40% at 24 weeks. A total of 11 obstructed kidneys had a functional share less than 40%, 5 increased to a share greater than 40% at age 24 weeks and 3 had decreasing share from age 4 to 24 weeks. Single kidney glomerular filtration rate of the contralateral kidneys was significantly increased at all ages. Volume of the contralateral kidney was significantly increased at age 4 and 12 weeks. CONCLUSIONS: The variability and course of renographic functional share in kidneys subjected to partial obstruction at age 2 weeks was similar to findings obtained in pigs obstructed at age 2 days. In contrast to these our study showed compensatory increase in function and size of the contralateral kidney, suggesting that contralateral compensation is an ability gained late in the nephrogenesis period.

Animals↗
PubMed2000

Evaluation of renal function in normal and hydronephrotic kidneys in rats using gadolinium diethylenetetramine-pentaacetic acid enhanced dynamic magnetic resonance imaging.

PURPOSE: Magnetic resonance imaging (MRI) is becoming established as a modality complementary to computerized tomography and ultrasound for evaluating kidney function. The evaluation of renal function during ureteral obstruction may be improved by contrast enhanced MRI. We evaluated dynamic changes in relative signal intensity in normal and hydronephrotic rat kidneys after intravenous injection of gadolinium (Gd) diethylenetetramine-pentaacetic acid (DTPA). MATERIALS AND METHODS: Using Gd-DTPA enhanced dynamic MRI we evaluated 35, 1-year-old rats, including 10 with partial and complete unilateral ureteral obstruction, respectively, and 15 with sham operated nonobstructed kidneys. Partial obstruction was created in 2-day-old rats by embedding the left ureter into the psoas muscle. Complete obstruction was created 10 days before MRI by placing a ligature around the upper third of the left ureter. MRI was performed before and 0.1 to 60 minutes after and intravenous injection of Gd-DTPA. We calculated relative signal intensity per time interval in the renal cortex, medulla and pelvis. RESULTS: Dynamic relative signal intensity patterns differed significantly among normal, and partially and completely obstructed kidneys. In normal kidneys signal intensity changes were divided into 3 phases after Gd-DTPA administration. During phase 1 rapid parenchymal uptake of Gd-DTPA within the initial minute after injection produced a rapid signal intensity decrease in the cortex, which achieved a minimum of 28% of pre-injection intensity. During phase 2 signal intensity decreased in the medulla and pelvis to a minimum of 18% and 22%, respectively, of pre-injection intensity within 5 minutes. During phase 3 significant relative signal intensity recovery began in the cortex at 7 minutes, and in the medulla and pelvis at 10 to 15 minutes, and lasted 30 to 60 minutes. In partially obstructed kidneys the 3 phases were significantly slower than in controls. In completely obstructed kidneys only phase 1 occurred within 60 minutes. CONCLUSIONS: Gd-DTPA enhanced dynamic MRI provides useful information for distinguishing obstructed from nonobstructed and partially from completely obstructed kidneys.

Animals↗
PubMed1999

[Topical steroids in the treatment of phimosis in children].

The aim of this study was to evaluate the efficacy of steroid application in the treatment of childhood phimosis. In a consecutive study 91 boys were treated with application of topical betamethason 0.05% cream twice daily. The foreskin was treated for one month, with an attempt at foreskin retraction after fourteen days. Treatment was controlled after one month and six months. Sixty boys achieved full retraction of the foreskin and nine had partial retraction and relief of symptoms. Twenty-two boys had unsatisfactory response and had an operation. Forty-five boys were controlled after six months, 13 had recurrence, of these nine were satisfied and free of symptoms, two had a new steroid treatment with full success, and two wanted a circumcision. A total of 74% did not need an operation after topical steroid treatment. No side-effects or complications were registered. Childhood phimosis can be successfully treated with steroid application, and the treatment should be offered prior to an operation.

Administration, Topical↗
PubMed1999

[Treatment of anal incontinence and constipation with transanal irrigation].

The Enema Continence Catheter (ECC) consists of a rectal catheter with an inflatable balloon. The balloon keeps the catheter in the rectum, while enemas are administered. Results from 25 adult patients and 12 children treated with the ECC were evaluated by telephone interviews or by information drawn from patient records. The ECC reduced the frequency of incontinence episodes in four of nine (44%) adult patients suffering from faecal incontinence due to spinal cord lesions, myelomeningocele, complicated anal sphincter lesions or anorectal surgery and irradiation therapy. Among 16 adult patients suffering from constipation or obstructed defecation, the ECC reduced symptoms in three (19%). Furthermore, the ECC procedure reduced symptoms in 10 of 11 (91%) children with colorectal dysfunction, mainly due to spina bifida. In conclusion, the ECC can reduce symptoms in most children suffering from faecal incontinence or constipation, and in some adults with faecal incontinence. However, the method is less effective among adults with constipation or obstructed defecation.

Adolescent↗
PubMed1999

Obstructive nephropathy: an update of the experimental research.

Ureteral obstruction (UO) is one of the most common problems confronting the urologist. Although large amounts of animal and clinical research have been done, the pathophysiologic mechanisms accompanying UO are not fully elucidated. Most of our knowledge on UO has been derived from experimental studies in a variety of animal models. Both antenatal and postnatal UO models have been developed mainly by ligation of the ureter or by burying the ureter into the psoas muscle. Most experimental studies have focused on short-term complete ureteral obstruction. The long-term effects of partial ureteral obstruction have been less intensively studied. It is now clear that obstructive nephropathy is not a simple result of mechanical impairment to urine flow but a complex syndrome resulting in alterations of both glomerular hemodynamics and tubular function caused by the interaction of a variety of vasoactive factors and cytokines that are activated in response to UO. Leukocyte infiltration appears to play an important role in obstructive nephropathy suggesting that UO also has an immunological component. Growth factors such as platelet-derived growth factor, transforming growth factor-beta, epidermal growth factor and insulin-like growth factor I may all play a role in the development and progression of fibrotic and sclerotic changes in the obstructed kidney. At present, the selection of patients with congenital hydronephrosis for operative treatment is controversial. Studies in animals and patients have shown that partial unilateral UO does not always cause a loss of renal function or progression in urinary tract dilation during long-term follow-up. The implications of UO continue to raise many questions and further work is necessary to achieve a better understanding of the pathogenesis in obstructive nephropathy.

Animals↗
PubMed1999

Contralateral compensatory kidney growth in rats with partial unilateral ureteral obstruction monitored by magnetic resonance imaging.

PURPOSE: We studied dynamic changes in total volume and renal vein blood flow in the kidneys contralateral to partial ureteral obstruction induced in newborn rats. MATERIALS AND METHODS: Using magnetic resonance imaging we investigated changes in total kidney volume and renal vein blood flow in 20 rats with mild and 18 with severe partial ureteral obstruction that was induced on the left side 2 days after birth. A total of 15 sham operated control rats were also studied. Total kidney volume and renal vein blood flow were monitored sequentially every 2 to 6 weeks for a total of 24 weeks. Renal parenchymal volume measured in vivo by magnetic resonance imaging was compared with that measured in vitro at week 24. RESULTS: Total volume and renal vein blood flow increased significantly in contralateral nonobstructed kidneys from week 14 and thereafter in rats with severe partial unilateral ureteral obstruction. At week 24 volume had increased by 22% and blood flow had increased by 25%. Volume and flow did not increase significantly in contralateral nonobstructed kidneys in rats with mild partial unilateral ureteral obstruction (p = 0.09). Before changes occurred in volume and blood flow in the contralateral nonobstructed kidneys, renal vein blood flow had decreased significantly from week 8 and thereafter in severely obstructed kidneys. In rats with mild partial unilateral ureteral obstruction renal vein blood flow decreased significantly in obstructed kidneys from week 18 and thereafter. Good correlation was noted between MRI in vivo and in vitro kidney volume measurements (r = 0.972, p <0.001). CONCLUSIONS: A significant increase in total volume and renal vein blood flow in contralateral nonobstructed kidneys did not develop immediately after the onset of detectable functional deterioration in partially obstructed kidneys. Therefore, caution should be used when incorporating compensatory growth into surgical decision making.

Animals↗
PubMed1998

Changes in nocturnal bladder capacity during treatment with the bell and pad for monosymptomatic nocturnal enuresis.

PURPOSE: We examined changes in nocturnal urine production and bladder capacity in enuretic children during bell and pad treatment. MATERIALS AND METHODS: A total of 18 children 7 to 11 years old with severe nocturnal enuresis had nocturnal urine production measured for a 14-day baseline period, which included daytime voidings on weekends. Thereafter, a 6-week treatment with the bell and pad was initiated, and nocturnal urine production and bladder capacity were monitored. RESULTS: Of 18 patients 10 became dry. Maximum daytime bladder capacities before treatment were fairly normal with no indication of treatment outcome. At the beginning of treatment maximum nocturnal bladder capacity was smaller than maximum daytime bladder capacity and during treatment it increased gradually. An increase in bladder volume during the enuretic episode was noted as well. No overall changes were found for nocturnal urine production. CONCLUSIONS: Treatment with the bell and pad is associated with a significant increase in nocturnal bladder capacity, in children who became dry and in those who remained wet. This increase explains why after attaining dryness the children were able to sleep through the night instead of having nocturia.

Child↗