Bone marrow metabolism is affected by body weight and response to exercise training varies according to anatomical location

AIM

High body weight is a protective factor against osteoporosis, but obesity also suppresses bone metabolism and whole-body insulin sensitivity. However, the impact of body weight and regular training on bone marrow (BM) glucose metabolism is unclear. We studied the effects of regular exercise training on bone and BM metabolism in monozygotic twin pairs discordant for body weight.

METHODS

We recruited 12 monozygotic twin pairs (mean ± SD age 40.4 ± 4.5 years; body mass index 32.9 ± 7.6, mean difference between co-twins 7.6 kg/m2 ; eight female pairs). Ten pairs completed the 6-month long training intervention. We measured lumbar vertebral and femoral BM insulin-stimulated glucose uptake (GU) using 18 F-FDG positron emission tomography, lumbar spine bone mineral density and bone turnover markers.

RESULTS

At baseline, heavier co-twins had higher lumbar vertebral BM GU (p < .001) and lower bone turnover markers (all p < .01) compared with leaner co-twins but there was no significant difference in femoral BM GU, or bone mineral density. Training improved whole-body insulin sensitivity, aerobic capacity (both p < .05) and femoral BM GU (p = .008). The training response in lumbar vertebral BM GU was different between the groups (time × group, p = .02), as GU tended to decrease in heavier co-twins (p = .06) while there was no change in leaner co-twins.

CONCLUSIONS

In this study, regular exercise training increases femoral BM GU regardless of weight and genetics. Interestingly, lumbar vertebral BM GU is higher in participants with higher body weight, and training counteracts this effect in heavier co-twins even without reduction in weight. These data suggest that BM metabolism is altered by physical activity.

Systemic cross-talk between brain, gut, and peripheral tissues in glucose homeostasis: effects of exercise training (CROSSYS). Exercise training intervention in monozygotic twins discordant for body weight

BACKGROUND

Obesity and physical inactivity are major global public health concerns, both of which increase the risk of insulin resistance and type 2 diabetes. Regulation of glucose homeostasis involves cross-talk between the central nervous system, peripheral tissues, and gut microbiota, and is affected by genetics. Systemic cross-talk between brain, gut, and peripheral tissues in glucose homeostasis: effects of exercise training (CROSSYS) aims to gain new systems-level understanding of the central metabolism in human body, and how exercise training affects this cross-talk.

METHODS

CROSSYS is an exercise training intervention, in which participants are monozygotic twins from pairs discordant for body mass index (BMI) and within a pair at least the other is overweight. Twins are recruited from three population-based longitudinal Finnish twin studies, including twins born in 1983-1987, 1975-1979, and 1945-1958. The participants undergo 6-month-long exercise intervention period, exercising four times a week (including endurance, strength, and high-intensity training). Before and after the exercise intervention, comprehensive measurements are performed in Turku PET Centre, Turku, Finland. The measurements include: two positron emission tomography studies (insulin-stimulated whole-body and tissue-specific glucose uptake and neuroinflammation), magnetic resonance imaging (brain morphology and function, quantification of body fat masses and organ volumes), magnetic resonance spectroscopy (quantification of fat within heart, pancreas, liver and tibialis anterior muscle), echocardiography, skeletal muscle and adipose tissue biopsies, a neuropsychological test battery as well as biosamples from blood, urine and stool. The participants also perform a maximal exercise capacity test and tests of muscular strength.

DISCUSSION

This study addresses the major public health problems related to modern lifestyle, obesity, and physical inactivity. An eminent strength of this project is the possibility to study monozygotic twin pairs that share the genome at the sequence level but are discordant for BMI that is a risk factor for metabolic impairments such as insulin resistance. Thus, this exercise training intervention elucidates the effects of obesity on metabolism and whether regular exercise training is able to reverse obesity-related impairments in metabolism in the absence of the confounding effects of genetic factors.

TRIAL REGISTRATION

ClinicalTrials.gov , NCT03730610 . Prospectively registered 5 November 2018.

Bone Marrow Metabolism Is Impaired in Insulin Resistance and Improves After Exercise Training

CONTEXT

Exercise training improves bone mineral density, but little is known about the effects of training on bone marrow (BM) metabolism. BM insulin sensitivity has been suggested to play an important role in bone health and whole-body insulin sensitivity.

OBJECTIVE

To study the effects of exercise training on BM metabolism.

DESIGN

Randomized controlled trial.

SETTING

Clinical research center.

PARTICIPANTS

Sedentary healthy (n = 28, 40-55 years, all males) and insulin resistant (IR) subjects (n = 26, 43-55 years, males/females 16/10).

INTERVENTION

Two weeks of sprint interval training or moderate-intensity continuous training.

MAIN OUTCOME MEASURES

We measured femoral, lumbar, and thoracic BM insulin-stimulated glucose uptake (GU) and fasting free fatty acid uptake (FFAU) using positron-emission tomography and bone turnover markers from plasma.

RESULTS

At baseline, GU was highest in lumbar, followed by thoracic, and lowest in femoral BM (all Ps < 0.0001). FFAU was higher in lumbar and thoracic than femoral BM (both Ps < 0.0001). BM FFAU and femoral BM GU were higher in healthy compared to IR men and in females compared to males (all Ps < 0.05). Training increased femoral BM GU similarly in all groups and decreased lumbar BM FFAU in males (all Ps < 0.05). Osteocalcin and PINP were lower in IR than healthy men and correlated positively with femoral BM GU and glycemic status (all Ps < 0.05).

CONCLUSIONS

BM metabolism differs regarding anatomical location. Short-term training improves BM GU and FFAU in healthy and IR subjects. Bone turnover rate is decreased in insulin resistance and associates positively with BM metabolism and glycemic control.

CLINICAL TRIAL REGISTRATION NUMBER

NCT01344928.

Intellectual disability in children aged less than seven years born moderately and late preterm compared with very preterm and term-born children - a nationwide birth cohort study

BACKGROUND

Prematurity has been shown to be associated with an increased risk of intellectual disability (ID).

METHOD

The aim was to establish whether the prevalence of ID, defined as significant limitations in both intellectual (intelligence quotient below 70) and adaptive functioning among moderately preterm (MP; 32⁺⁰ -33⁺⁶  weeks) and late preterm (LP; 34⁺⁰ -36⁺⁶  weeks) infants, is increased compared with that in term infants (≥37⁺⁰  weeks). Antenatal and neonatal risk factors for ID among gestational age groups were sought. The national register study included all live-born infants in Finland in 1991-2008, excluding those who died before one year age, or had any major congenital anomaly or missing data. A total of 1 018 256 infants (98.0%) were analysed: very preterm (VP; <32⁺⁰  weeks, n = 6329), MP (n = 6796), LP (n = 39 928) and term (n = 965 203).

RESULTS

By the age of seven years, the prevalence of ID was 2.48% in the VP group, 0.81% in the MP group, 0.55% in the LP group and 0.35% in the term group. Intracranial haemorrhage increased the ID risk in all groups. Male sex and born small for gestational age predicted an increased risk in all but the MP group.

CONCLUSIONS

The prevalence of ID decreased with increasing gestational age. Prevention of intracranial haemorrhages may have a beneficial effect on the neurodevelopmental outcomes of neonates.

First Tarsometatarsal Joint Derotational Arthrodesis for Flexible Hallux Valgus: Results from Follow-Up of 3-8 Years

PURPOSE

We report 3- to 8-year follow-up results for the first tarsometatarsal joint derotational arthrodesis.

METHODS

A total of 70 patients (88 feet) with symptomatic flexible hallux valgus were operated between 2003 and 2009. In all, 66 patients (94.3%) with 84 (95.5%) feet were enrolled in retrospective analysis; of those, 58 (87.9%) patients with 76 (90.5%) feet were followed for a mean of 5.1 (range: 3.0-8.3) years. Preoperative, 6 week postoperative, and late follow-up weightbearing radiographs were evaluated along with clinical examination and questionnaires.

RESULTS

The mean hallux valgus angle improved 13.4° (95% confidence interval: 11.6-15.1, p < .001) at the latest follow-up, while the mean intermetatarsal angle correction was 4.5° (95% confidence interval: 3.7-5.2, p < .001). There were three (4.0%) nonunions, and seven (9.2%) feet needed reoperation during follow-up.

CONCLUSION

First tarsometatarsal joint derotational arthrodesis is an effective procedure for correcting flexible hallux valgus deformity and provides a satisfactory long-term outcome.

In vivo comparison of delayed gadolinium-enhanced MRI of cartilage and delayed quantitative CT arthrography in imaging of articular cartilage

OBJECTIVE

To compare delayed gadolinium-enhanced magnetic resonance imaging (MRI) of cartilage (dGEMRIC) and delayed quantitative computed tomography (CT) arthrography (dQCTA) to each other, and their association to arthroscopy. Additionally, the relationship between dGEMRIC with intravenous (dGEMRIC(IV)) and intra-articular contrast agent administration (dGEMRIC(IA)) was determined.

DESIGN

Eleven patients with knee pain were scanned at 3 T MRI and 64-slice CT before arthroscopy. dQCTA was performed at 5 and 45 min after intra-articular injection of ioxaglate. Both dGEMRIC(IV) and dGEMRIC(IA) were performed at 90 min after gadopentetate injection. dGEMRIC indices and change in relaxation rates (ΔR(1)) were separately calculated for dGEMRIC(IV) and dGEMRIC(IA). dGEMRIC and dQCTA parameters were calculated for predetermined sites at the knee joint that were International Cartilage Repair Society (ICRS) graded in arthroscopy.

RESULTS

dQCTA normalized with the contrast agent concentration in synovial fluid (SF) and dGEMRIC(IV) correlated significantly, whereas dGEMRIC(IA) correlated with the normalized dQCTA only when dGEMRIC(IA) was also normalized with the contrast agent concentration in SF. Correlation was strongest between normalized dQCTA at 45 min and ΔR(1,IV) (r(s) = 0.72 [95% CI 0.56-0.83], n = 49, P < 0.01) and ΔR(1,IA) normalized with ΔR(1) in SF (r(s) = 0.70 [0.53-0.82], n = 52, P < 0.01). Neither dGEMRIC nor dQCTA correlated with arthroscopic grading. dGEMRIC(IV) and non-normalized dGEMRIC(IA) were not related while ΔR(1,IV) correlated with normalized ΔR(1,IA) (r(s) = 0.52 [0.28-0.70], n = 50, P < 0.01).

CONCLUSIONS

This study suggests that dQCTA is in best agreement with dGEMRIC(IV) at 45 min after CT contrast agent injection. dQCTA and dGEMRIC were not related to arthroscopy, probably because the remaining cartilage is analysed in dGEMRIC and dQCTA, whereas in arthroscopy the absence of cartilage defines the grading. The findings indicate the importance to take into account the contrast agent concentration in SF in dQCTA and dGEMRIC(IA).

Topographical variation of T2 relaxation time in the young adult knee cartilage at 1.5 T

OBJECTIVE

To assess the normal topographical variation of T2 relaxation time of articular cartilage in different compartments of the knee joint and at different tissue depths in young healthy adults.

METHODS

Twenty asymptomatic young adult volunteers (age range, 21-27 years; mean age, 22.5 years), were studied at 1.5T. Both axial and sagittal multi-slice multi-echo spin echo measurements were performed to determine the T2 relaxation time of cartilage in the femoral, tibial and patellar compartments. The cartilage surfaces were divided into 24 segments and each segment was divided into deep and superficial regions-of-interest (ROIs) of equal thickness. The reproducibility for ROI analysis was assessed for five patients by determining the interclass correlation coefficient (ICC) and the root-mean-square coefficient of variation (CV(RMS)).

RESULTS

Cartilage T2 was significantly dependent on joint topography, compartment and tissue depth. For all joint surfaces, superficial T2 values were systematically higher as compared to deep tissue. The data showed a trend toward higher T2 values at the load bearing area of the femoral condyles. The interobserver error varied significantly among different locations and showed mostly good reproducibility with mean ICC of 0.70 and a CV(RMS) of 5.0%.

CONCLUSION

The normal variation in cartilage T2 within a joint is significant and should be acknowledged when pathology-related T2 changes are investigated. The knowledge on normal variation can be used for power and sample size calculations in further studies, and the T2 values as control data in future patient studies.

Reproducibility of imaging human knee cartilage by delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) at 1.5 Tesla

OBJECTIVE

The purpose of this study was to investigate the day-to-day reproducibility of the delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) measurement at different knee joint surfaces in healthy subjects at 1.5 Tesla (T).

METHODS

The dGEMRIC experiment was repeated for 10 asymptomatic volunteers three times with an average interval of 5 days between scans. The measurement was performed from a single sagittal slice through the center of the lateral femoral condyle and from the center of the patella in the axial plane. Cartilage was manually segmented into superficial, deep and full-thickness regions of interests (ROIs) at different topographical locations of the femur, tibia and patella. The reproducibility was evaluated separately for each ROI as well as for the entire bulk cartilage in the slice of each joint surface.

RESULTS

The reproducibility at various ROIs expressed by root-mean-square average coefficient of variation (CV(RMS)) ranged between 4.7-12.9%. Thirty out of thirty-three ROIs showed a CV(RMS) less than 10%. Intraclass correlation coefficient (ICC) ranged between 0.45 and 0.98. The CV(RMS) and ICC for bulk dGEMRIC were 4.2% and 0.95 for femur, 5.5% and 0.87 for tibia, and 4.8% and 0.97 for patella.

CONCLUSIONS

The dGEMRIC technique showed good day-to-day reproducibility, on the average 8% for small deep or superficial segments, 7% for full-thickness ROIs and 5% for bulk ROIs covering all visible cartilage in a single joint surface. We conclude that dGEMRIC imaging at field strength 1.5 T can be used as a reliable instrument for the assessment of articular cartilage when staff has been carefully trained.

Magnetic resonance-guided growth plate bone bridge resection at 0.23 Tesla: report of a novel technique

BACKGROUND

Growth plate or physeal cartilage trauma may result in delayed or immediate failure of growth due to bone bridge formation at the insult site. With computed tomography (CT) and magnetic resonance imaging (MRI), the role of imaging has expanded from diagnosis to treatment planning and therapy guidance.

PURPOSE

To describe a technique for MR-guided growth plate bone bridge resection and to evaluate feasibility of the procedure.

MATERIAL AND METHODS

Three consecutive patients with growth plate bone bridges were treated surgically under MR guidance. All bridges were detected with prior MRI and radiographs. All patients were referred to procedure due to growth plate bridge associated growth anomaly and pertaining clinical symptoms. The effect of the treatment was evaluated after 48 months with a clinical follow-up.

RESULTS

All bridges were successfully detected, marked, and removed under MRI guidance. All patients had relief from their symptoms. Two patients had lasting results from the operation with no further operative treatment needed or scheduled at 48 months from primary treatment. There was one clinical failure, with the patient requiring repeated osteotomies.

CONCLUSION

We have successfully implemented a novel therapy for growth plate bridge resection.

Patellar cartilage lesions: comparison of magnetic resonance imaging and T2 relaxation-time mapping

PURPOSE

To evaluate the detection and the size of focal patellar cartilage lesions in T2 mapping as compared to standard clinical magnetic resonance imaging (MRI) at 1.5T.

MATERIAL AND METHODS

Fifty-five consecutive clinical patients referred to knee MRI were imaged both with a standard knee MRI protocol (proton-density-weighted sagittal and axial series, T2-weighted sagittal and coronal series, and T1-weighted coronal series) and with an axial multislice multi-echo spin-echo measurement to determine the T2 relaxation time of the patellar cartilage. MR images and T2 maps of patellar cartilage were evaluated for focal lesions. The lesions were evaluated for lesion width (mm), lesion depth (1/3, 2/3, or 3/3 of cartilage thickness), and T2 value (20-40 ms, 40-60 ms, or 60-80 ms) based on visual evaluation.

RESULTS

Altogether, 36 focal patellar cartilage lesions were detected from 20 human subjects (11 male, nine female, mean age 40+/-15 years). Twenty-eight lesions were detected both on MRI and T2 maps, while eight lesions were only visible on T2 maps. Cartilage lesions were significantly wider (P = 0.001) and thicker (P<0.001) on T2 maps as compared to standard knee MRI. Most lesions 27 had moderately (T2 40-60 ms) increased T2 values, while two lesions had slightly (T2 20-40 ms) and seven lesions remarkably (T2 60-80 ms) increased T2 relaxation times.

CONCLUSION

T2 mapping of articular cartilage is feasible in the clinical setting and may reveal early cartilage lesions not visible with standard clinical MRI.

Reliability of the evaluation of multidetector computed tomography images from the scanner's console in high-energy blunt-trauma patients

PURPOSE

To evaluate the reliability of a structured 5-min evaluation of multidetector computed tomography (MDCT) images from the scanner's console in high-energy trauma patients.

MATERIAL AND METHODS

Forty patients were scanned with four-slice MDCT using a standardized trauma protocol. Image evaluation covered the thorax, abdomen, and pelvis. The radiologist scrolled axial images on the scanner's console using three different window settings (lung, soft tissue, and bone) and performed a prospective structured evaluation of the traumatic lesions. The findings were compared to the final radiological diagnosis of the MDCT data made on a PACS workstation, the operative findings, and the clinical follow-up.

RESULTS

Evaluation from the scanner's console enabled the diagnosis of all potential life-threatening injuries, the sensitivity for all injuries being 60% and specificity 98%.

CONCLUSION

A PACS workstation is needed for the final diagnosis of all injuries, but this rapid screening method can reliably detect all injuries that require instant care.

Magnetic resonance imaging-guided diskography and diagnostic lumbar 0.23T MRI: an assessment study

PURPOSE

To describe the in vivo appearance of magnetic resonance imaging (MRI) diskograms of normal and degenerated lumbar intervertebral disks, and to evaluate the differences in imaging findings between sequential diagnostic MRI and MRI diskography.

MATERIAL AND METHODS

Nine consecutive patients underwent MRI-guided diskography in order to determine possible pain provocation during puncture and contrast medium injection. All patients had preceding clinical suspicion of lumbar diskogenic pain and findings of lumbar disk degeneration in diagnostic (MRI, computed tomography (CT), plain radiography). A 0.23T open MRI scanner with interventional tools was used for imaging and instrument guidance. On all patients, a complementary diagnostic MRI study of the lumbar spine before and after the MRI-guided disk injection was performed, and subsequent axial MRI diskograms were obtained.

RESULTS

A total of 25 disk punctures were initialized, and 25 MRI diskograms were obtained and their expression described. There was a correlation between the degenerative disk findings visualized by diagnostic MRI and MRI diskograms.

CONCLUSION

The use of gadolinium contrast media in MRI-guided diskography enables the evaluation of MRI diskograms. Our results suggest that MRI-guided diskography can be used to substitute conventional diskography or CT-diskography and as an augmenting method to assess diagnostic information upon degenerative processes of the lumbar spine.

MR-guided interventional procedures: a review

Magnetic resonance imaging (MRI) has emerged as a potential guidance tool for a variety of procedures. Diagnostic and therapeutic procedures using either open surgical or percutaneous access are performed. They span from simple lesion targeting and biopsy to complex applications requiring multiple tasks performed simultaneously or in rapid succession. These tasks include instrument guidance and therapy monitoring as well as procedural follow-up. The interventional use of MRI (IMRI) is increasing steadily. This article reviews the prerequisites, systems, and clinical interventional procedures of IMRI.

Value of multidetector computed tomography in assessing blunt multitrauma patients

PURPOSE

To find out if multidetector computed tomography (MDCT), using a dedicated trauma protocol, provides sufficient diagnostic information of the injuries of blunt multitrauma patients to enable the planning of treatment for all body compartments.

MATERIAL AND METHODS

One-hundred-and-thirty-three patients exposed to high-energy trauma were referred and scanned with the standardized MDCT multitrauma protocol. The imaging protocol consisted of axial scanning of the head and helical scanning of the facial bones, cervical spine, thorax, abdomen, and pelvis. The scanning times were 12 s for the head, 19-21 s for the facial bones and cervical spine (1 mm collimation), and 32-50 s for the thorax, abdomen, and pelvis (2 mm collimation). One-hundred-and-forty milliliters of non-iodinated contrast material (300 mg I/ml) was administered intravenously at 3 ml/s.

RESULTS

Ninety-nine of the patients (74%) had at least one finding consistent with trauma. The most frequent findings were in the thorax in 58 patients (44%). Nineteen false-negative findings and two false-positive findings were made. The overall sensitivity of MDCT was 94%, specificity 100%, and accuracy 97%.

CONCLUSION

MDCT is accurate in the assessment of blunt multitrauma patients. The decision to treat the patient can be made on the basis of MDCT with a reasonable level of certainty.

MRI-guided abdominal biopsy in a 0.23-T open-configuration MRI system

The purpose of this study was to test the hypothesis that when ultrasound (US) guidance is not feasible, abdominal biopsies can be performed safely and accurately under magnetic resonance imaging (MRI) guidance in a low-field environment. MRI-guided abdominal biopsy was performed on 31 consecutive patients, in whom US-guided abdominal biopsy was not possible because the lesion was not visualized in US (n=27) or an US-guided procedure was not considered safe (n=4). The locations of the lesions were liver (n=14), pancreas (n=6), lymph node (n=4), retroperitoneal mass (n=3), adrenal gland (n=3) and spleen (n=1). The average size of the lesion was 2.2 cm (range 1-4 cm) in maximum diameter. All procedures were done by using a 0.23-T open-configuration C-arm-shaped MRI scanner with interventional optical tracking equipment and software. Fine-needle aspiration (FNA) biopsy was performed on all 31 patients; 18 patients underwent both FNA biopsy and cutting needle core biopsy. Procedures were evaluated for diagnostic sensitivity, specificity and accuracy as well as procedure time and complications. The FNA biopsy specimens were adequate for interpretation in 27 (87%) of 31 cases. Two of these proved to be false-negative findings during follow-up or subsequent biopsy. The final diagnosis was malignant in 15 and benign in 16 patients. The sensitivity, specificity and accuracy of FNA biopsy were 71, 100 and 81%, respectively. Of the 18 core-needle biopsies, one was determined false-negative owing to nonrepresentativeness. The sensitivity, specificity and accuracy of histological samples were 90, 100 and 94%, respectively. The needle time was 19 min on average and the mean room time was 1 h 48 min. No immediate or late complications occurred. MRI-guided abdominal biopsy can be performed safely and accurately in a low-field environment in patients for whom an US-guided procedure is not feasible.

Sacro-iliac joint arthrography in low back pain: feasibility of MRI guidance

OBJECTIVE

Evaluation of the feasibility of MR-guidance in sacro-iliac joint arthrography in patients whose low back pain is suspected to arise from the sacro-iliac joint (SIJ).

METHODS AND PATIENTS

Twenty patients with low back pain underwent MR-guided sacro-iliac joint arthrography. Needles made from titanium (size 20 G, MDTech, USA) were used. For image guidance a 0.23T open-configuration C arm magnet (Proview, Marconi Medical Systems, USA) with special interventional hardware and software package (I-Path 200, Marconi Medical Systems) containing an MR compatible in-room console, large-screen (36") display, optical navigator and accompanying software with dedicated sequences was used. No other image guidance modalities were used.

RESULTS

MR-guided SIJ arthrography was successfully performed in all twenty patients without complications. The optimal imaging sequence both for preoperative and intraoperative images was 3D-Gradient Echo sequence. The dispersal of the injected saline and anaesthetic could be determined inside the joint in all cases with heavily T2-weighted fast spin echo sequence. In the present study, 60% of the patients had significant reduction of pain after sacro-iliac joint arthrography and sacro-iliac joint was considered to be the source of patients low back pain in these patients.

CONCLUSION

The present study shows that MR guidance with open configuration low field scanner is an accurate guiding method for sacro-iliac joint arthrography.

Gastroesophageal endoscopic findings and gastrointestinal symptoms in preterm neonates with and without perinatal indomethacin exposure

BACKGROUND

The aim of this study was to investigate whether perinatal indomethacin treatment has effects on the development of esophageal and gastric lesions in preterm infants and to evaluate other potential etiologic factors behind these lesions.

METHODS

Sixty-nine infants were born at less than 33 weeks' gestation. Forty-five of these infants underwent treatment with perinatal indomethacin (study group) and 24 did not (control group). All underwent upper gastrointestinal tract endoscopy and biopsy during the neonatal period. The correlation between gastrointestinal symptoms, abnormal endoscopic findings, and the factors correlating with the development of esophageal and gastric mucosal lesions was evaluated.

RESULTS

Abnormal endoscopic findings were equally common in the study group (77.8%) and in controls (83.3%). There was no dependence between gastrointestinal symptoms and endoscopic findings because only 15 infants (21.7%) were symptomatic before endoscopy. The interval between endoscopy and the last perinatal indomethacin dose correlated significantly with abnormal esophageal findings and gastric mucosal lesions. Shorter duration of enteral feeding before endoscopy correlated with greater risk of abnormal esophageal findings. Older gestational age and need of ventilator treatment at the time of endoscopy remained the risk factors associated with abnormal gastric findings.

CONCLUSIONS

Esophageal and gastric lesions diagnosed by endoscopy correlate poorly with the gastrointestinal symptoms of patients. Short duration of enteral feeding seems to be correlated with an increased risk of esophageal mucosal lesions, increasing gestational age and ventilator treatment with gastric mucosal lesions, and perinatal indomethacin with esophageal and gastric mucosal lesions in preterm infants. Ventilator-treated preterm infants not receiving enteral nutrition and patients with indomethacin exposure might benefit from ulcer prophylaxis.

Renal follow up of premature infants with and without perinatal indomethacin exposure

AIMS

To evaluate early childhood renal growth, structure, and function in children born at less than 33 weeks gestation and to investigate possible independent effects of perinatal indomethacin exposure.

METHODS

A total of 66 children born at less than 33 weeks gestation, 31 of them with perinatal indomethacin exposure (study group) and 35 without (control group), were examined at 2-4 years of age. Serum cystatin C and protein; plasma creatinine, sodium, and potassium; urine protein, calcium:creatinine ratios, and alpha(1) microglobulin; and glomerular filtration rate (GFR) were determined. Renal sonography examinations were performed.

RESULTS

The mean serum cystatin C concentrations were slightly higher in the control group than in the study group. Mean values of serum protein, and plasma creatinine and sodium did not differ between the groups, neither did median plasma potassium concentrations and urine protein:creatinine and calcium:creatinine ratios. None had tubular proteinuria. Abnormal GFR (<89 ml/min/1.73 m(2)) was found in one case in each group and renal structural abnormalities in five in each group. In logistic regression analysis the duration of umbilical artery catheter (UAC) use and furosemide treatment emerged as the significant independent risk factors for renal structural abnormalities. Furosemide treatment and assisted ventilation remained the risk factors associated with renal abnormalities in general-that is, functional and/or structural abnormal findings.

CONCLUSION

Perinatal indomethacin does not seem to affect long term renal growth, structure, or function in children born at less than 33 weeks gestation. Duration of UAC use, furosemide treatment, and assisted ventilation may be correlated with later renal structural and functional abnormalities.

Nerve root infiltration of the first sacral root with MRI guidance

The purpose of this clinical trial was to describe the methodology and evaluate the accuracy of optical tracking-based magnetic resonance (MR)-guided infiltration of the first sacral (S1) root. Thirty-five infiltrations were performed on 34 patients with a 0. 23-T open C-arm magnet installed in a fully equipped operation room with large-screen (36 inches) display and optical navigator utilizing infrared passive tracking. T1 and T2 fast spin-echo (FSE) images were used for localizing the target and fast field echo for monitoring the procedure. Saline as contrast agent in single-shot (SS)FSE images gave sufficient contrast-to-noise ratio. Twenty-four patients had unoperated L5/S1 disc herniation, and 10 had S1 root irritation after failed back surgery. Needle placement was successful in 97% of the cases, and no complications occurred. Outcome was evaluated 1-6 months (mean 2.2 months) after the procedure and was comparable to that of other studies using fluoroscopy or computed tomography guidance. MR-guided placement of the needle is an accurate technique for first sacral root infiltration.

Perinatal indomethacin treatment and neonatal complications in preterm infants

To evaluate the incidence of neonatal complications among infants exposed to indomethacin antenatally, postnatally or both ante-and postnatally (combined), the records of 240 infants of gestational ages between 23 to 32 weeks were analysed retrospectively. Antenatal indomethacin treatment for longer than 2 days with a daily or cumulative dosage >/=150 mg correlated with a significantly higher incidence of grade I-II intraventricular haemorrhage. Combined exposure, cumulative antenatal exposure >/=150 mg and duration of antenatal exposure of more than 2 days was associated with necrotising enterocolitis and a cumulative exposure with sepsis. There was no independent association between indomethacin exposure and pneumothorax, bronchopulmonary dysplasia or respiratory distress syndrome.

CONCLUSION

Preterm infants with exposure to antenatal indomethacin might be at increased risk of grade I and II intraventricular haemorrhage and those with both ante- and postnatal exposure at an increased risk of necrotising enterocolitis and sepsis.

MR imaging in tibial shaft fractures. A potential method for early visualization of delayed union

PURPOSE

To evaluate the relationship between MR findings at the fracture site during the healing process and the outcome of patients with tibial shaft fracture.

MATERIAL AND METHODS

Twelve consecutive patients with an uncomplicated tibial fracture treated conservatively were imaged by MR 1 to 3 days, 1 week, 3 weeks, 6 weeks and 12 weeks after the trauma. MR imaging consisted of sagittal/coronal T1-weighted, T2-weighted, proton density, short-tau inversion recovery, and contrast-enhanced T1-weighted spin-echo images. The images were analysed for the extent of signal pathology in the bone marrow adjacent to the fracture, the extent of soft tissue oedema, and the intensity and homogeneity of the contrast enhancement of the callus.

RESULTS

The differences between normal (n=7) and delayed union (n=5) were observed within 3 to 6 weeks after the trauma, mainly in the homogeneity of the callus in T2-weighted and contrast-enhanced images.

CONCLUSION

MR imaging is a potentially valuable method for early visualization of delayed union in tibial shaft fractures.

Short versus prolonged indomethacin therapy for patent ductus arteriosus in preterm infants

OBJECTIVE

To evaluate whether a prolonged low-dose course of indomethacin would produce an improved closure rate and have fewer side effects compared with a short standard dosage schedule in the management of patent ductus arteriosus (PDA) in preterm infants.

STUDY DESIGN

Sixty-one infants of gestational ages 24 to 32 weeks with a PDA confirmed with echocardiography were randomized to receive 0.2 to 0.1 to 0.1 mg/kg indomethacin in 24 hours (short course, n = 31) or 0.1 mg/kg every 24 hours 7 times (long course, n = 30). Echocardiography was done 3, 9, and 14 days after the treatment was started, and side effects were monitored.

RESULTS

Primary PDA closure occurred more often in the short course group (94% vs 67%, P =.011), but the sustained closure rates were not different (74% vs 60%). Surgical PDA ligations were less frequent in the short course group than in the long course group. The short course group had a shorter duration of oxygen supplementation, less frequent symptoms of necrotizing enterocolitis, and a lower rate of urea retention. Mortality and other neonatal morbidity rates were similar.

CONCLUSION

A prolonged low-dosage indomethacin regimen offers no advantage compared with a standard-dosage short course in the management of a hemodynamically significant PDA in preterm infants.