Morphological and morphometric features of sacral hiatus and its clinical significance in caudal epidural anaesthesia.

BACKGROUND: Caudal epidural block (CEB) failure or complications are not unheard even among experienced anaesthesiologists and are usually due to sacral hiatus (SH) anatomy variations. The aim of the present study is to observe, record and analyse important anatomical features of SH and correlate them with potential CEB limitations. MATERIALS AND METHODS: The SH of 155 complete and undamaged Greek adult dry sacra of known sex were included in the study. Three non-metric (shape of SH and location of hiatal apex and base in relation to level of sacral/coccygeal vertebra) and five metric parameters (height of the SH, transverse width of the SH at the base, anteroposterior diameter of the SH at the level of its apex and the distance from the sacral apex and base to the upper border of S2 foramina) were evaluated. RESULTS: Inverted U (34.83%) and inverted V (26.45%) were the commonest shapes. Hiatal apex and base were most commonly related to the level of S4 (78.70%) and S5 vertebra (89.03%), respectively. Mean height, depth and intercornual distance were 19.05 ± 8.65 mm, 5.39 ± 1.84 mm and 12.41 ± 3.16 mm, respectively, whereas mean distance between the upper border of S2 foramen and the apex and base of the SH were 46.34 mm and 63.48 mm, respectively. Anatomical variations of SH that might be responsible for CEB failure, such as elongated SH, absence of SH, complete dorsal wall agenesis of sacral canal and narrowing (< 3 mm) at the apex of SH were found in 17.43% of sacra (male 10.94% and female 25.22%). CONCLUSIONS: This study suggests a potential risk of failure of CEB in Greek patients, especially in females, which should be kept in mind while giving caudal epidural anaesthesia.

Bilateral Femoral Neuropathy: A Rare Complication of Drug Overdose due to Prolonged Posturing in Lithotomy Position.

BACKGROUND: Bilateral femoral neuropathy is an uncommon complication of various surgical and nonsurgical procedures, such as pelvic/abdominal surgery or vaginal delivery. Case Report. We report a case of a 41-year-old male who was found unresponsive against the wall in a "lithotomy-type" position with both knees flexed at approximately 90 degrees and both hips flexed and externally rotated at approximately 90 and 60 degrees, respectively, 24-48 hours after a drug overdose (combination of dihydrocodeine, paracetamol, diazepam, and amitriptyline). During his recovery, he complained of severe bilateral proximal lower limb weakness and bilateral distal lower limb pain and allodynia. His symptoms were initially attributed to critical illness myopathy/neuropathy (CIMN). However, thorough clinical and neurophysiological evaluation revealed that his symptoms were due to severe bilateral femoral neuropathies. CONCLUSIONS: To our knowledge, this is the first reported case of bilateral femoral nerve palsy due to prolonged posturing in a "lithotomy-type" position in the context of a drug overdose.

Impact of Helicobacter pylori on multiple sclerosis-related clinically isolated syndrome.

OBJECTIVES: There are no data regarding the relationship between Helicobacter pylori infection (Hp-I) and clinically isolated syndrome (CIS) suggestive of multiple sclerosis. The purpose of this pilot study was to investigate the association between active Hp-I, confirmed by histology, and CIS and to evaluate the impact of Hp eradication on the CIS clinical course. MATERIAL AND METHODS: We conducted a study on 48 patients with CIS and 20 matched controls. At baseline, apart from histology, serum anti-Hp-specific IgG titer, inflammatory mediators, and HLA-A, HLA-B, HLA-DR genetic polymorphisms were estimated. Hp-positive patients received standard triple eradication regimen, and all patients were followed up for 2 years. RESULTS: The prevalence of Hp-I was significantly higher in patients with CIS (43/48, 89.6%) than in control (10/20, 50%) (P < 0.001, OR: 8.6, 95% CI: 2.4-30.8). When compared with controls, patients with CIS also showed significantly higher serum anti-Hp IgG titer and HLA-A26, HLA-A30, and HLA-B57 frequencies. Hp-positive patients also showed higher serum concentrations of inflammatory cytokines and homocysteine. At 2-year clinical endpoint, in the subgroup of CIS patients with successful Hp eradication, the number of patients who presented with a second episode was significantly lower accompanied by significant improvement in mean Expanded Disability Status Scale score. CONCLUSIONS: Hp-I seems more frequent in a Greek CIS cohort and its eradication might delay CIS progression, suggesting a possible link between Hp-I and CIS.

Cholinergic deficiency in Alzheimer's and Parkinson's disease: evaluation with pupillometry.

The aim of the study was to evaluate the cholinergic deficiency in Alzheimer's (AD) and Parkinson's disease (PD). For this purpose, pupil size changes and mobility were assessed using a fast-video pupillometer (263 frames/s). Twenty-three (23) patients with probable AD and twenty-two (22) patients with PD (eleven with cognitive impairment and eleven without) entered the study. A full record of the pupil's reaction to light was registered. From this data ten (10) parameters were measured and reported. Comparison of those parameters in both group of subjects followed. Patients with probable AD had abnormal pupillary function compared to healthy ageing. All the Pupil Light Reflex (PLR) variables significantly differed between the two groups (p<0.005) except the Baseline Pupil Diameter after 2-min dark adaptation (D1) and the Minimum Pupil Diameter (D2). Maximum Constriction Acceleration (ACmax) was the best predictor in classifying a subject as normal or as an AD with a perfect classification ability (AUC=1, p<0.001). ACmax and Maximum Constriction Velocity (VCmax) were significantly lower in PD patients without and with coexisting cognitive impairment compared to normal subjects (p<0.001). Patients with cognitive impairment had significantly lower levels of ACmax, VCmax and amplitude (AMP=D1-D2) than patients with no cognitive deficits. ACmax and secondarily VCmax were the best predictors in classifying a subject as normal or as a PD patient with or without cognitive impairment. Cognitive and memory impairment, which reflects a cholinergic deficit, may be a crucial pathogenetic factor for the decrease in the aforementioned pupillometric parameters. VCmax and ACmax can be considered as the most sensitive indicators of this cholinergic deficiency.

Evaluation of pupil mobility in patients with myasthenia gravis.

The aim of this study is to investigate the effect of Myasthenia Gravis (MG) on the Central Nervous System (CNS) and/or the smooth muscles of the iris through pupillometry. Sixteen recently diagnosed Myasthenic and sixteen non-Myasthenic subjects of matching age and gender underwent a pupillometric study of the effects of single flash stimuli of 24.6 candelas/m2 intensity and 20 msec duration. A significant decrease in Amplitude (p < 0.001), Maximum Constriction Velocity (p < 0.001) and especially Maximum Constriction Acceleration with a perfect discrimination ability (AUC= 1, p < 0.001). was observed in the Myasthenic compared to the non-Myasthenic subjects. In contrast, no significant difference was observed in Baseline Pupil Radius (R1) and 3.5 secs Percentage Recovery-Redilatation (R%) (p = 0.051 and p = 0.517, respectively). Of the parameters that are studied, R1 and R% are governed mainly by the action of the Sympathetic Nervous System (SNS) and the rest by the Parasympathetic Nervous System (ParNS), through Acetylcholine. The analysis of these parameters demonstrates that the SNS remains unaltered while the ParNS may be affected in MG. This post-synaptic cholinergic receptors' deficit may be central, within the CNS, or peripheral, related to the Neuromuscular Junction of the iris' sphincter.

Effect of age on pupillary light reflex: evaluation of pupil mobility for clinical practice and research.

PURPOSE: The aim of this study was to provide a data base for the measurement of various parameters of the pupil light reflex in normal subjects using a fast video pupillometry device (262 frames/sec). METHOD: One hundred healthy subjects took part in the study aged 44.31+/-18.11 years. Subjects were divided in two (2) groups according to age: 18-50 years of age (group 1) and 51-81 years of age (group 2). All subjects were examined between 09.00 and 15.00 and the re-test examination was repeated exactly 24 hours later. All variables showed satisfactory test-retest reliability (Pearson test-retest showed values over 0. 70 for all parameters besides Time for Maximum Constriction (T3. 0.62) and Recovery (R%: 0.57)). RESULTS: The Latency of pupil reaction to light (Ti) was not affected by Age. Baseline Pupil Radius (RI) after 2 min of dark adaptation was statistically smaller in the elderly group p < 0.001; Maximum Constriction Velocity (VCmax), Maximum Constriction Acceleration (ACmax) and Amplitude (AMP) were significantly smaller in the elderly group (p < 0.001) when compared to group 1. When all parameters were studied their correlation showed a statistical significant difference for R1, R2, VCmax, ACmax and AMP when related to Age. However when Age was taken into account through the use of partial correlation, the relation between R1, R2 and AMP remained unaltered, but the relations between R1 and VCmax and ACmax were dramatically reduced from -0.39 to -0.21 and from -0.45 to -0.09 respectively indicating that the relation observed between Ri and VCmax and ACmax was due mainly to the Age of the subjects. CONCLUSION: The results suggest that age influences Baseline Pupil Size, Maximum Constriction Velocity (VCmax) and Acceleration (ACmax), while the Latency of the light reflex remains unaltered.