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Postoperative Reduction (postoperative + reduction)
Selected AbstractsWhite matter changes in normal pressure hydrocephalus and Binswanger disease: specificity, predictive value and correlations to axonal degeneration and demyelinationACTA NEUROLOGICA SCANDINAVICA, Issue 6 2002M. Tullberg Objectives, To analyse the diagnostic and prognostic value of periventricular hyperintensity (PVH) and deep white matter hyperintensity (DWMH) magnetic resonance imaging (MRI) changes and their relation to symptoms and cerebrospinal fluid (CSF) markers of demyelination (sulphatide) and axonal degeneration [neurofilament triplet protein (NFL)] in a large series of patients with normal pressure hydrocephalus (NPH) and Binswanger disease (BD). Materials and methods, PVH and DWMH were determined by a semi-automatic segmentation method on T2-weighted images in 29 patients with NPH and 17 patients with BD. CSF analyses, psychometric testing and quantification of balance, gait and continence were performed in all patients and also postoperatively in NPH patients. Results, No MRI variable could identify NPH or BD patients. Abundant PVH and DWMH preoperatively correlated with improvement in gait, balance and psychometric performance after shunt surgery (P < 0.05). CSF sulphatide correlated positively with the amount of DWMH (P < 0.05) while NFL was correlated to both PVH and DWMH (P < 0.05). Abundant PVH correlated with poor psychometric performance while DWMH correlated with gait disturbance (P < 0.05). Postoperative reduction in PVH correlated with improvement in gait, balance and psychometric performance. Conclusion, In spite of a refined quantification method, NPH and BD patients exhibited similar MRI changes. MRI had a predictive value in NPH patients. DWMH might relate to demyelination and PVH to neuronal axonal dysfunction. NPH and BD share the major part of symptoms and MRI changes, indicating a common pathophysiological pattern, and we raise the question of how to treat BD patients. [source] Corneal hysteresis using the Reichert ocular response analyser: findings pre- and post-LASIK and LASEKACTA OPHTHALMOLOGICA, Issue 2 2008Caitriona Kirwan Abstract. Purpose:, To evaluate and compare corneal hysteresis in patients prior to and following laser in situ keratomileusis (LASIK) and laser-assisted subepithelial keratectomy (LASEK) using the Reichert ocular response analyser (ORA). Methods:, Corneal hysteresis was recorded prior to and 3 months after corneal laser refractive surgery for myopia. Preoperative corneal hysteresis was correlated with age and preoperative central corneal thickness (CCT). Postoperative corneal hysteresis was correlated with postoperative CCT in both the LASIK and LASEK treatment groups. The correlations between postoperative change in hysteresis and stromal ablation depth, percentage of tissue ablated, optical zone and patient age were also examined. Results:, A total of 84 eyes of 84 patients were involved in the study. LASIK was performed in 63 eyes and LASEK in 21. Mean preoperative corneal hysteresis of all eyes was 10.8 ± 1.5 mmHg. Mean age, preoperative CCT, corneal hysteresis and ablation profile were similar in both groups. A statistically significant decrease in hysteresis occurred following LASIK (p < 0.01) and LASEK (p < 0.01) with similar decrements observed in both treatment groups. A moderate correlation was found between postoperative hysteresis and postoperative CCT in LASIK (r = 0.7) and LASEK (r = 0.7) treated eyes. A weak correlation was found between postoperative decrease in hysteresis and the parameters examined. Conclusion:, Corneal hysteresis decreased following LASIK and LASEK. Similar reductions occurred following both procedures, indicating that LASIK involving a thin 120-,m flap did not induce additional biomechanical change. Postoperative reduction in hysteresis did not correlate with the amount or percentage of corneal tissue removed, nor with optical zone or patient age. [source] Ventricular cerebrospinal fluid neurofilament protein levels decrease in parallel with white matter pathology after shunt surgery in normal pressure hydrocephalusEUROPEAN JOURNAL OF NEUROLOGY, Issue 3 2007M. Tullberg Normal pressure hydrocephalus (NPH) is characterized by disturbed cerebrospinal fluid (CSF) dynamics and white matter lesions (WML). Although the morphology of these lesions is described, little is known about the biochemistry. Our aim was to explore the relationship between ventricular CSF markers, periventricular WML and postoperative clinical outcome in patients with NPH. We analysed lumbar and ventricular concentrations of 10 CSF markers, 12 clinical symptoms and signs, magnetic resonance imaging (MRI) periventricular white matter hyperintensities (PVH) and ventricular size before and 3 months after shunt surgery in 35 patients with NPH. Higher ventricular CSF neurofilament protein (NFL), an axonal marker, correlated with more extensive PVH. A larger postoperative reduction in NFL correlated with larger reduction in PVH and a more pronounced overall improvement. Albumin ratio, HMPG, NPY, VIP and GD3 increased postoperatively whereas NFL, tau and HVA decreased. Variations in ventricular size were not associated with CSF concentrations of any marker. We conclude that NPH is characterized by an ongoing periventricular neuronal dysfunction seen on MRI as PVH. Clinical improvement after shunt surgery is associated with CSF changes indicating a restitution of axonal function. Other biochemical effects of shunting may include increased monoaminergic and peptidergic neurotransmission, breakdown of blood brain barrier function, and gliosis. [source] MRI-based evaluation of locus and extent of neurotoxic lesions in monkeys ,HIPPOCAMPUS, Issue 4 2001e Málková Abstract To minimize the variability in the extent of lesions made by injections of the excitotoxin ibotenic acid in rhesus monkeys, we developed and validated an MRI-based method to determine the efficacy of the injections soon after surgery. T2-weighted MR images were obtained 6,11 days after surgery from 17 brain hemispheres of monkeys that had received bilateral lesions of either the hippocampal formation (HF), perirhinal cortex, or parahippocampal cortex. The extent of lesion estimated from the hypersignal that appeared in and outside of the targeted area on these MR images was compared with the extent of damage assessed histologically after survival periods ranging from 120,370 days. Highly significant correlations (r values between 0.85,0.99) were found between these two measures for several regions in the medial temporal lobe. Based on this finding, lack of hypersignal in the targeted area of some Ss was followed by successful reinjection of the neurotoxin to create more complete cell loss prior to the postoperative phase of the study. We also assessed the relationship between a postoperative reduction in HF volume, measured from T1-weighted MR images, and the extent of damage determined histologically in 14 hemispheres of monkeys with bilateral excitotoxic HF lesions. The HF volume decreases sharply after surgery until 40,50 days postoperatively, after which there is only a minor further decrease. Based on this finding, we obtained T1-weighted MR images at least 44 days but in most cases close to 1 year after surgery. A highly significant positive correlation (r = 0.95, P < 0.001) was found between neuronal damage and volume reduction, with nearly complete neuronal damage (96,99%) corresponding to a volume reduction of 68,79%. These MRI-based methods thus provide an accurate in vivo evaluation of the locus and extent of neurotoxic lesions. Application of these methods can ensure that each animal in the experiment is used effectively. Hippocampus 2001;11:361,370. Published 2001 Wiley-Liss, Inc. [source] Atrial Size Reduction as a Predictor of the Success of Radiofrequency Maze Procedure for Chronic Atrial Fibrillation in Patients Undergoing Concomitant Valvular SurgeryJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 8 2001MIEN-CHENG CHEN M.D. Radiofrequency Maze Procedure and Atrial Size.Introduction: Previous studies showed that the surgical maze procedure can restore sinus rhythm and atrial transport function in patients with chronic atrial fibrillation (AF). However, no previous studies discussed the association of atrial size reduction and the success of sinus conversion by the radiofrequency (RF) maze procedure for chronic AF. Methods and Results: A total of 119 chronic AF patients undergoing valvular operations were included in this study. Sixty-one patients received RF and cryoablation to create lesions in both atria to simulate the surgical maze II or III procedure (RF maze II or RF maze III; 13 patients, group 1) or a modified maze pattern (RF maze "IV"; 48 patients, group 2). The other 58 patients who underwent valvular operations alone without the maze procedure served as control (group 3). At 3-month follow-up after operation, sinus rhythm was restored in 73%, 81%, and 11% of patients in groups 1, 2 and 3, respectively. Preoperative left and right atrial sizes were not statistically significant predictors of sinus conversion by the RF maze procedure. However, as a result of postoperative reduction of atrial sizes, postoperative left atrial diameter was significantly smaller in patients who had sinus conversion by the RF maze procedure than in patients who did not regain sinus rhythm (45.0 ± 7.0 mm vs 51.0 ± 8.0 mm; P = 0.03). Postoperative right atrial area of patients who had sinus conversion by the RF maze procedure also was significantly smaller than that of patients who did not regain sinus rhythm (18.1 ± 4.4 cm2 vs 28.5 ± 8.2 cm2; P = 0.008). Conclusion: Atrial size reduction appears to predict the success of sinus conversion with the RF maze procedure used in conjunction with valvular surgery. [source] Evaluation of Radiofrequency Thermal Ablation Results in Inferior Turbinate Hypertrophies by Magnetic Resonance ImagingTHE LARYNGOSCOPE, Issue 4 2007Tarik Sapci MD Abstract Objectives: Nasal obstruction caused by inferior turbinate hypertrophies is one of the most frequent problems in otolaryngology. Treatment of this disease may involve medical and surgical methods. Thermal ablation with radiofrequency energy has become quite popular in the recent years as one of the surgical methods used when medical therapy is not adequate. Study Design: Prospective, clinical trial. Methods: Thermal ablation with radiofrequency energy was used in this study on the inferior turbinates of 21 patients who had nasal obstruction caused by inferior turbinate hypertrophy only. The results were evaluated subjectively by preoperative and postoperative patient- and physician-assigned visual analogue scales and objectively by magnetic resonance imaging (MRI) investigation. Results: By the end of the postoperative week 10, 64.76% recovery was detected according to the patient evaluation, and 40.75% recovery was detected according to the physician evaluation. Measurement of the average volumes of the inferior turbinates by MRI revealed a 8.70% postoperative reduction. The most significant change was detected in the anterior-posterior length measurement performed in the axial plane. Conclusions: These results suggest that thermal ablation with radiofrequency energy is an easily applied, efficient, and reliable technique in treatment of the inferior turbinate hypertrophy, and that anterior-posterior length measurement in the axial section of the inferior turbinate by MRI, which is thought as an objective evaluation method, could be an efficient diagnostic tool in detecting the efficiency of radiofrequency on inferior turbinate. [source] Anatomical and functional outcome in brilliant blue G assisted chromovitrectomyACTA OPHTHALMOLOGICA, Issue 5 2010Paul B. Henrich Abstract. Purpose:, To evaluate the potential of brilliant blue G (BBG) for intraoperative staining of the inner limiting membrane (ILM) with respect to staining properties and surgical outcome. Methods:, In a retrospective, non-comparative clinical case series, we analysed 17 consecutive chromovitrectomy interventions for surgery of macular holes, ERMs, vitreoretinal traction syndromes and cystoid macular oedema. Following complete posterior vitreous detachment, BBG was injected into the vitreous cavity at a concentration of 0.25 mg/ml, followed by immediate washout. Main outcome measures were staining properties, visual acuity, central visual field testing and optical coherence tomography (OCT) measurements over a mean follow-up period of 3 months. Results:, ILM staining was somewhat less intensive for BBG than for average indocyanine green (ICG) chromovitrectomy. However, the ILM was removed successfully without additional ICG in 15/17 patients. Postoperative visual acuity was improved in 16/17 patients and remained unchanged in one patient. Central retinal OCT thickness showed a postoperative reduction, with values ranging from +7 to ,295 ,m (median ,89 ,m). Neither visual field defects nor any other adverse events were recorded. Conclusion:, BBG permits sufficient staining for safe ILM removal. In this short-term study, good anatomical and functional results were achieved and no adverse events were observed. [source] Temporal changes in retinal thickness after removal of the epiretinal membraneACTA OPHTHALMOLOGICA, Issue 4 2009Hitoshi Aso Abstract. Purpose:, We aimed to study the temporal aspects of the postoperative reduction of retinal thickness in eyes with epiretinal membrane after vitrectomy with peeling of the epiretinal membrane and internal limiting membrane. Methods:, In a retrospective study performed as a non-comparative, interventional case series, 16 eyes from 15 patients with idiopathic epiretinal membrane who underwent vitrectomy and removal of the epiretinal membrane were followed up using optical coherence tomography measurements. Retinal thickness in the macular area was assessed by the foveal thickness and macular volume in a circle 6 mm in diameter. Results:, Scattergrams of the foveal thickness and macular volume were best fitted with exponential curves. The average time constants of the exponential curve for foveal thickness and macular volume changes were 31 days (range 4,109 days) and 36 days (range 5,100 days), respectively. The average expected final values for foveal thickness and macular volume were 334 ,m (range 206,408 ,m) and 7.53 mm3 (range 6.57,8.66 mm3), respectively, which were significantly greater than those in normal controls (p < 0.0001, t -test). Conclusions:, Retinal thickness decreases rapidly immediately after surgical removal of the epiretinal membrane and the reduction rate gradually slows thereafter. Approximation of the exponential curve provides an estimation of final retinal thickness after surgical removal of the epiretinal membrane; final thickness is expected to be greater than in normal eyes. [source] | ||||||||||