CT-guided sacroiliac joint injection: Easy or difficult? : 53

Purpose: Fluoroscopy-guided sacroiliac joint (SIJ) injections are technically difficult to perform because of the complex anatomy with helicoidal conformation of the joint. Our study describes the procedure of CT-guided SIJ injection, its feasibility and its rate of success. Methods and materials: Retrospective study included 46 consecutive patients. The procedure was performed by 3 MSK radiologists and consisted in a puncture with a posterior approach in the inferior articular part of SIJ, then in an injection of iodinated contrast agent (1ml) with CT control of SIJ space opacification and finally in an injection of slowacting corticosteroid. The SIJ approach was noticed as correct if there was an inferior articular puncture and if the needle was in the articular space, and as impossible if there was ankylosis or osteophytosis. The study was divided in two successive periods: period 1 (4 first months) and period 2 (12 last months). Results: SIJ opacification was successful in 57% (26/46). We observed a learning curve: opacification was succeeded in 66% (23/35) and there was incorrect approach in 9% (3/35) during period 2 versus respectively 27% (3/11) and 45% (5/11) during period 1. Causes of failure were incorrect approach in 40% (6/20 too low, 2/20 too high), impossible approach in 30% (6/20) and unexplained in 30% (6/20). Mean duration of procedure was about 28 minutes. No complication occurred. Conclusion: CT guided SIJ injection is safe and successful in 66% after a training period. The success depends on SIJ correct approach and also on anatomical lesions.

Neuronal potential of cells in early postnatal rat sciatic nerve.

A population of undifferentiated cells with neuronal potentialities were revealed in rat sciatic nerve. Explant cultures of sciatic nerve were prepared from newborn or early postnatal rat. Cultures were growth in F14 medium supplemented with 10% of fetal calf serum, incubated in a humidified 3% CO2, 97% air atmosphere. Within 2 weeks, refractile cells exhibiting the morphology of neurons were observed in all examined cultures. These cells had ovoid or multipolar refractile cells bodies with extended cytoplasmic processes. The neuronal nature of these cells was confirmed by their immunostaining with specific neuronal markers: neurofilament triplets, neuron-specific enolase, peripherin, microtubule-associated proteins, and brain spectrin. This neuronal population displayed various phenotypes. The CO2 concentration in the incubator plays an important role, since the number of differentiated neurons was lower in cultures incubated in 5% CO2. Since the sciatic nerve is devoid of nerve cell bodies in vivo, we concluded that early postnatal sciatic nerve contains crest cells with neuronal potentialities differentiating into neurons in response to the culture's environmental cues.

Evaluation of prenatal diagnosis of congenital heart diseases by ultrasound: experience from 20 European registries.

OBJECTIVES: To evaluate prenatal diagnosis of congenital heart diseases by ultrasound investigation in well-defined European populations. DESIGN: Data from 20 registries of congenital malformations in 12 European countries were included. The prenatal ultrasound screening programs in the countries ranged from no routine screening to three ultrasound investigations per patient routinely performed. RESULTS: There were 2454 cases with congenital heart disease with an overall prenatal detection rate of 25%. Termination of pregnancy was performed in 293 cases (12%). There was considerable variation in prenatal detection rate between regions, with the lowest detection rates being in countries without ultrasound screening (11%) and in Eastern European countries (Croatia, Lithuania and Ukraine; 8%). In Western European countries with ultrasound screening, detection rate ranged from 19-48%. There was a significant difference in prenatal detection rate and proportion of induced abortions between isolated congenital heart disease and congenital heart disease associated with chromosome anomalies, multiple malformations and syndromes (P < 0.0001). There were 1694 cases with isolated congenital heart disease of which 16% were diagnosed prenatally. Malformations affecting the size of the ventricles were detected prenatally in half of the cases. CONCLUSIONS: Prenatal detection rate of congenital heart disease varies significantly between countries even with the same screening recommendations. The presence of associated malformations significantly increases the prenatal detection rate.

Patterns of extraocular muscle weakness in vasculopathic pupil-sparing, incomplete third nerve palsy.

OBJECTIVE: To determine the pattern of extraocular muscle (EOM) paresis in incomplete vasculopathic third nerve palsies (3NP) that have normal pupillary function. METHODS: A retrospective study in a private practice and academic neuro-ophthalmic practice. Patients diagnosed with vasculopathic 3NP within 4 weeks of symptom onset were identified. The chart of each patient was reviewed to determine pupillary function and the pattern and degree of EOM and levator palpebrae paresis at the time of presentation. RESULTS: Of 55 patients with vasculopathic 3NP, 42 (76%) had normal pupillary function. Of these 42, 23 (55%) demonstrated an incomplete EOM palsy, defined as partially reduced ductions affecting all third nerve-innervated EOMs and levator (diffuse pattern) or partially reduced ductions that involved only some third nerve-innervated EOMs and levator (focal pattern). Twenty (87%) of these 23 patients showed a diffuse pattern of paresis; only three (13%) showed a focal pattern of paresis, one that affected only the superior rectus and levator muscles (superior division weakness). CONCLUSIONS: Based on our series, most patients with EOM/levator involvement in pupil-sparing, incomplete 3NP of vasculopathic origin have a diffuse pattern of paresis. In contrast, our review of the literature suggests that pupil-sparing 3NP of aneurysmal origin usually have a focal pattern of paresis. We propose that distinguishing these two patterns of EOM paresis may be helpful in differentiating between vasculopathic and aneurysmal 3NP. Future studies will be needed to confirm the clinical utility of this hypothesis.

The spared nerve injury model of neuropathic pain.

The spared nerve injury (SNI) model mimics human neuropathic pain related to peripheral nerve injury and is based upon an invasive but simple surgical procedure. Since its first description in 2000, it has displayed a remarkable development. It produces a robust, reliable and long-lasting neuropathic pain-like behaviour (allodynia and hyperalgesia) as well as the possibility of studying both injured and non-injured neuronal populations in the same spinal ganglion. Besides, variants of the SNI model have been developed in rats, mice and neonatal/young rodents, resulting in several possible angles of analysis. Therefore, the purpose of this chapter is to provide a detailed guidance regarding the SNI model and its variants, highlighting its surgical and behavioural testing specificities.

Fluoroscopy-guided procedures in cardiology: is patient exposure being reduced over time?

The number of fluoroscopy-guided procedures in cardiology is increasing over time and it is appropriate to wonder whether technological progress or change of techniques is influencing patient exposure. The aim of this study is to examine whether patient dose has been decreasing over the years. Patient dose data of more than 7700 procedures were collected from two cardiology centres. A steady increase in the patient dose over the years was observed in both the centres for the two cardiological procedures included in this study. Significant increase in dose was also observed after the installation of a flat-panel detector. The increasing use of radial access may lead to an increase in the patient exposure. The monitoring of dose data over time showed a considerable increase in the patient exposure over time. Actions have to be taken towards dose reduction in both the centres.

Mutations in the epithelial Na+ channel ENaC outer pore disrupt amiloride block by increasing its dissociation rate.

The epithelial Na+ channel ENaC mediates transepithelial Na+ transport in the distal kidney, the colon, and the lung and is a key element for the maintenance of Na+ balance and the regulation of blood pressure. Mutagenesis studies have identified residues alphaS583 and the homologous betaG525 and gammaG537 in the outer pore entrance that are critical for ENaC block by the K+-sparing diuretic amiloride. The aim of the present study was to determine first, whether these residues are part of the amiloride binding site, and second, whether they are general determinants of ENaC block by amiloride and its derivatives. Kinetic analysis of the association and dissociation rates of amiloride and benzamil to ENaC showed that mutation of residue alphaS583C and the homologous betaG525C increased the dissociation rate of the drugs from the binding site, with little changes in their association rate. Thus, these mutations destabilize the binding interaction between the blockers and the receptor on the channel, favoring the unbinding of the ligand. This strongly suggests that they are part of the binding site. Because mutations of alphaS583, betaG525, and gammaG537 have similar effects on amiloride, benzamil, and triamterene block, we conclude that these three ENaC blockers share a common receptor within the ion channel pore.

Video-assisted thoracoscopic resection of a small pulmonary nodule after computed tomography-guided localization with a hook-wire system. Experience in 45 consecutive patients.

BACKGROUND: This study is a single-institution validation of video-assisted thoracoscopic (VATS) resection of a small solitary pulmonary nodule (SPN) previously localized by a CT-guided hook-wire system in a consecutive series of 45 patients. METHODS: The records of all patients undergoing VATS resection for SPN preoperatively localized by CT-guided a hook-wire system from January 2002 to December 2004 were assessed with respect to failure to localize the lesion by the hook-wire system, conversion thoracotomy rate, duration of operation, postoperative complications, and histology of SPN. RESULTS: Forty-five patients underwent 49 VATS resections, with simultaneous bilateral SPN resection performed in 4. Preoperative CT-guided hook-wire localization failed in two patients (4%). Conversion thoracotomy was necessary in two patients (4%) because it was not possible to resect the lesion by a VATS approach. The average operative time was 50 min. Postoperative complications occurred in 3 patients (6%), one hemothorax and two pneumonia. The mean hospital stay was 5 days (range: 2-18 days). Histological assessment revealed inflammatory disease in 17 patients (38%), metastasis in 17 (38%), non-small-cell lung cancer (NSCLC) in 4 (9%), lymphoma in 3 (6%), interstitial fibrosis in 2 (4%), histiocytoma in one (2%), and hamartoma in one (2%). CONCLUSIONS: Histological analysis of resected SPN revealed unexpected malignant disease in more than 50% of the patients indicating that histological clarification of SPN seems warranted. Video-assisted thoracoscopic resection of SPN previously localized by a CT-guided hook-wire system is related to a low conversion thoracotomy rate, a short operation time, and few postoperative complications, and it is well suited for the clarification of SPN.

Intravitreal ranibizumab for age-related macular degeneration - optical coherence tomography guided retreatment intervals and their intra- and inter-individual variability

PURPOSE:To determine whether the need for retreatment after an initial loading phase of 3 monthly intravitreal injections of ranibizumab shows an intra-individual regular rhythm and to what degree it varies between different patients.SETTING:Prospective mono-centre cohort study.METHODS:Prospective study with 42 patients with exudative age-related macular degeneration (AMD), treatment na?ve, giving informed consent. Loading dose of 3 monthly doses of ranibizumab (0,5mg), followed by a 12 months pro re nata (PRN) regimen according to early exudative signs on spectral domain optical coherence tomography (HD-OCT Cirrus Zeiss?, cube 512x126). The follow-up visits were intensified (week 4, 5, 6, 7, 8, 10, 12, 14, 16, 20, 24, etc after each injection) in order to detect exudative recurrences early, and injection followed within 3 days in cases of subretinal fluid, or intraretinal cysts, or central thickness increase of >50?m. Intervals were calculated between injections and the following recurrence was calculated for the 12 month follow-up with PRN treatment. Variability was expressed as standard deviation (SD). RESULTS Visual acuity (VA) improved from a mean ETDRS letter score of 61.6 (SD 10.8) at baseline to 68.0 (SD 10.2, +6.4 letters) at month 3 and increased further to 74.7 (SD 9.0, +13.1 letters from baseline) at month 12. The 15 patients who have completed the study by October 2010 showed maintenance of the VA improvement. Retinal thickness of the central foveal subfield improved from a mean value of 366?m(baseline) to 253?m(month 3), well maintained thereafter. Mean number of injections was 8.8 (SD 3.5) per 12 months of follow-up (after 3 loading doses), ranging from 0 to 12, with mean individual treatment-recurrence intervals ranging from 28 to >365 days (mean 58 days). Intraindividual variability of treatment-recurrence intervals, measured as SD of the individual intervals, was 7.1days as a mean value(range 1.7 ? 22.6 days) for the 33 patients with more than 1 injection during follow-up. SD was higher for longer intervals of an individual patient. It ranged within 20% of the mean intra-individual interval for 30 patients(91%) and within 15% for 21 patients(64%). The first interval was within 1 week of the mean intra-individual interval in 64% of patients and within 2 weeks in 89% of patients.CONCLUSIONS:The majority of AMD patients showed a relatively stable rhythm for PRN injections of intravitreal ranibizumab after initial loading phase, associated with excellent functional and anatomical results. The initial interval between last loading dose and first recurrence may have a predictive value for further need of treatment, therefore potentially facilitating follow-up and patient care.

Effect of Vagus Nerve Stimulation in an Adult Patient with Dravet Syndrome: Contribution to Sudden Unexpected Death in Epilepsy Risk Reduction?.

We report on a patient who developed, from 5 months of age, multiple seizure types, including myoclonic, associated with severe psychomotor delay, leading to the diagnosis of Dravet syndrome. Over the years, he developed refractory epilepsy and was implanted with a vagus nerve stimulator at the age of 19. After 3 months, he experienced a progressive improvement of partial and generalized seizures, with a >90% reduction, and better alertness. This meaningful clinical improvement is discussed in the light of the sudden unexpected death in epilepsy risk, which is high in this setting, and seems remarkably diminished in our patient in view of the reduction of generalized convulsions.

Pulse pressure variation-guided fluid therapy after cardiac surgery: A pilot before-and-after trial.

PURPOSE: The aim of this study is to study the feasibility, safety, and physiological effects of pulse pressure variation (PPV)-guided fluid therapy in patients after cardiac surgery. MATERIALS AND METHODS: We conducted a pilot prospective before-and-after study during mandatory ventilation after cardiac surgery in a tertiary intensive care unit. We introduced a protocol to deliver a fluid bolus for a PPV ≥13% for at least >10 minutes during the intervention period. RESULTS: We studied 45 control patients and 53 intervention patients. During the intervention period, clinicians administered a fluid bolus on 79% of the defined PPV trigger episodes. Median total fluid intake was similar between 2 groups during mandatory ventilation (1297 mL [interquartile range 549-1968] vs 1481 mL [807-2563]; P = .17) and the first 24 hours (3046 mL [interquartile range 2317-3982] vs 3017 mL [2192-4028]; P = .73). After adjusting for several baseline factors, PPV-guided fluid management significantly increased fluid intake during mandatory ventilation (P = .004) but not during the first 24 hours (P = .47). Pulse pressure variation-guided fluid therapy, however, did not significantly affect hemodynamic, renal, and metabolic variables. No serious adverse events were noted. CONCLUSIONS: Pulse pressure variation-guided fluid management was feasible and safe during mandatory ventilation after cardiac surgery. However, its advantages may be clinically small.

Role of intra-operative duplex ultrasound in living renal donor transplantation

Objective: The treatment of choice in end-stage renal disease is¦transplantation.¦Hemodynamic disturbances can evoke graft loss, while early ultrasound¦identification of vascular problems improves outcome. The primary endpoint¦of this study was to identify differences in post-op complications with and¦without systematic, intraoperative Doppler ultrasound use. A secondary aim¦was to find a predictive resistance index limit which would show where surgical¦reintervention was necessary.¦Methods: Between Jan 2000 and Dec 2010, 108 renal transplants were¦performed from living donors at our institution. In group 1 (n = 67),¦intra-operative duplex ultrasound and intra-parenchymatous resistance index¦measurements assessed patients, while in group 2 (n = 41), no ultrasound was¦performed.¦Results. There were no inter-group differences in the overall post-op¦complication rate or in benefit to graft or patient survival with Doppler use,¦however, significantly more vascular complications (10% vs. 0%, p = 0·02) and¦more acute rejections (37% vs. 10%) occurred in group 2 than in group 1,¦respectively. When the resistance index was <0·5 intra-operatively, immediate¦surgical revision was undertaken to raise the index >0·6.¦Results: There were no inter-group differences in the overall post-op¦complication rate or in benefit to graft or patient survival with Doppler use,¦however, significantly more vascular complications (10% vs. 0%, p = 0·02) and¦more acute rejections (37% vs. 10%) occurred in group 2 than in group 1,¦respectively. When the resistance index was <0·5 intra-operatively, immediate¦surgical revision was undertaken to raise the index >0·6.¦Conclusion: This is the first report demonstrating benefits of systematic¦intraoperative Doppler ultrasound on post-operative complications in renal¦transplantation from living donors. Our results support surgical revision with a¦resistance index <0·5.

Imaging for trans-catheter pulmonary stent-valve implantation without angiography: role of intravascular ultrasound.

Patients with stenosed biologic pulmonary conduits require redo cardiac surgery to prevent severe right ventricular dysfunction. Following the latest trends, the trans-catheter pulmonary stent-valve implantation represents a new fascinating alternative carrying a lower operative risk, compared with the standard open-heart re-intervention. Traditionally, the pulmonary stent valve is positioned off pump, under fluoroscopic control, and requires angiographies. However, alternative tools not requiring contrast injections for the intra-operative cardiac imaging have to be also considered strongly. The usefulness of intravascular ultrasound for the positioning of aortic endoprosthesis has already been proven in previous reports and, following the same principle, we have started to routinely implant balloon-expandable stent valves (Edwards Sapien? THV) in stenosed pulmonary valve conduits using intravascular ultrasound for the stent-valve positioning without angiography. We describe the intra-operative intravascular imaging technique with technical details.