Spatial anatomy of the round ligament,gallbladder, and intrahepatic vessels in patients with right-sided round ligament of the liver

Purpose

To analyze the vascular structure of the liver in patients with a right-sided round ligament.

Methods

We reviewed 16 patients with a right-sided round ligament and 3 polysplenia and situs inversus patients with a left-sided round ligament who underwent multidetector row CT with contrast media. The patient population consisted of 13 men and 6 women (mean 62 years). We analyzed the axial and volume-rendered images for the location of the round ligament, gallbladder, portal veins, hepatic veins, and hepatic artery. The following imaging findings for the patients with polysplenia and situs inversus were horizontally reversed.

Results

The prevalence of a right-sided round ligament with and without polysplenia was 75 and 0.11 %, respectively. The gallbladder was located to the right, below, and left of the round ligament in 27.7, 38.8 and 33.3 %, respectively. Independent branching of the right posterior portal vein was noted in 57.8 %. PV4 was difficult to identify in 36.8 %. The middle hepatic vein was located to the left of the round ligament. Two branching patterns for the lateral and medial branches of the right anterior hepatic artery were noted: the common (44.4 %) and separated types (55.5 %). Both of the right anterior hepatic artery and portal vein ramified into two segments; the lateral segment with many branches and the medial segment with a few branches.

Conclusions

The right-sided round ligament divided the right anterior section into the lateral and medial segments based on the portal vein and hepatic artery anatomy.

     

Rare saccular aneurysm in a medial type persistent trigeminal artery trunk and literature review

Purpose

We report an extremely rare case of saccular aneurysm in the left medial type persistent trigeminal artery (PTA) trunk and discuss its clinical importance.

Materials and methods

A 77-year-old woman who had symptom suggestive of vertebrobasilar insufficiency underwent cerebral magnetic resonance (MR) imaging and non-contrast three dimensional time-of-flight MR angiography (3D TOF MRA) using a 3 T scanner.

Results

3D TOF MRA images revealed a left medial type PTA originated from the left internal carotid artery C5 portion, through cavernous sinus and connected to the basilar artery with a saccular aneurysm in the mid portion of its trunk. The basilar artery (BA) under the union was hypoplastic. The bilateral posterior communicating arteries were absent.

Conclusion

To our knowledge, this is the first report of a medial type PTA associated with a saccular aneurysm in the PTA trunk. Being aware of this is crucial in clinical, because they can influence surgical and interventional procedures.     

Cartilage-Hair Hypoplasia: Follow-Up of Immunodeficiency in Two Patients

Purpose

To study the changes in the immunological status in 2 children with cartilage hair hypoplasia (CHH).

Methods

A 4–6 year immunological follow-up from infancy.

Results

In infancy the children presented a combined T cell and B cell immunodeficiency which partly resolved in time. Mitogen-induced T cell proliferation values fluctuated but lymphopenia has remained constant. Both patients had no recent thymic emigrants (TREC). Both children have suffered from a prolonged viral infection. Hypogammaglobulinemia normalized during the first years of life but both children have a specific antibody deficiency (SAD).

Conclusions

The changes in the immunological status in CHH patients emphasize the importance of a regular follow-up. SAD should be searched for in CHH. The absence of TRECs supports combined immunodeficiency and possible need of hematopoietic stem cell transplantion.     

Persistent trigeminal artery: a cross-sectional study based on over 3 years conventional angiography,CT angiography and MR angiography images

Purpose

The trigeminal artery is one of the four primitive anastomosis established between the internal carotid artery and the vertebrobasilar system that regresses at the sixth week of embryonic development. Its persistence in adult life (PTA) is usually found incidentally. The aim of this study is to determine its prevalence, main characteristics and clinical significance.

Methods

A cross-sectional study was performed over the last 3 years, 2012–2014, to analyze images performed on conventional angiography, CT angiography and MR angiography of patients who attended the Neuroradiology Department of the Hospital Universitario Doce de Octubre in Madrid, Spain, to control their underlying pathology.

Results

Nine cases of PTA were found (prevalence 0.37 %, two men, seven women; three right, six left; age range 13–88 years). Eight PTA emerged from the cavernous ICA and one from the petrous segment. Six cases were lateral or petrosal type and one was medial or sphenoidal type. The whole PTAs anastomosed the BA, six at the middle third and three at the distal third. Weon et al.’s type 3 was predominant. CVD incidence was 55.6 % and aneurysm incidence was 22 %.

Conclusions

PTA prevalence was similar to those previously reported, being commonly left-sided, Salas et al.’s lateral or petrosal type, Weon et al.’s type 3 and with no gender predominance. CVD and aneurysms incidence in the presence of a PTA were higher than in general population. Its anatomical relations make it essential to consider its presence and directional blood flow when planning endovascular and neurosurgical treatments.

     

Coaptation/elevation role of the middle deltoid muscle fibers: a static biomechanical pilot study using shoulder MRI

Purpose

It is generally recognized that the middle deltoid muscle fibers (MDMF) have an elevating effect on the humeral head at small abduction angles. These forces are normally counterbalanced by the coaptation effect of the rotator cuff (RC) muscles to maintain shoulder stability. With RC tears, this balance may be jeopardized leading to shoulder dysfunction. Conversely, not all patients with RC tears develop shoulder dysfunction. The purpose of this study was to investigate the coaptation/elevation forces (CEF) ratio of the MDMF in RC tears subjects and in volunteers, using magnetic resonance imaging (MRI).

Methods

Magnetic resonance imaging images in 10 subjects with RC tears and in five volunteers were used to build a three-dimensional model of the shoulder. The CEF ratio of the MDMF was estimated by representing the glenohumeral joint as a pulley.

Results

The CEF ratio increased from the posterior to the anterior fibers of the MDMF.The median and interquartile range (IQR) of the CEF ratios of the posterior-third, middle-third, anterior-third and anterior-surface segments of the deltoid were: 0.16 (IQR = 0.23), 0.61 (IQR = 0.4), 1.42 (IQR = 0.41), 1.94 (IQR = 0.56) in subjects, and 0.06 (IQR = 0.24), 0.45 (IQR = 0.28), 1.32 (IQR = 1.01), 1.49 (IQR = 0.39) in volunteers. In the subjects, the CEF ratio of the anterior-surface segment was greater than all other segments (P ≤ 0.03).

Conclusions

The CEF ratio of the MDMF increased from its posterior segment to its anterior segment, indicating a greater stabilizing effect of the anterior segment both in RC tears subjects and in volunteers. Strengthening of the anterior fibers of the MDMF could potentially improve shoulder function in subjects with RC tears.     

Applied anatomy of small branches of the portal vein in transverse groove of hepatic hilum

Purpose

The objective of this study was to provide the morphological details on small branches of the portal vein in transverse groove of hepatic hilum.

Methods

According to the surgery significance, the small branches of portal vein in transverse groove of hepatic hilum were named as “Short hepatic portal veins (SHPVs)”. SHPVs were minutely dissected in 30 adult cadaveric livers. The number, diameter, length, origin points, and entering liver sites of SHPVs were explored and measured.

Results

There were 181 SHPVs in 30 liver specimens, including 46 % (83/181) from the left portal vein, 31 % (56/181) from the bifurcation, and 23 % (42/181) from the right portal vein. At the entering liver sites of SHPVs, 22 % (40/181) supplied for segment IV, 9 % (17/181) for segment V, 4 % (7/181) for segment VI, 23 % (41/181) for segment VII, and 42 % (76/181) for segment I (caudate lobe). There were 6.0 ± 2.4 branches per liver specimen with range 3–12. The mean diameter of SHPVs was 2.25 ± 0.89 mm. The average length of SHPVs was 4.86 ± 2.12 mm.

Conclusions

SHPVs widely existed in each liver specimen. The detailed anatomical study of SHPVs could be useful to avoid damaging the short portal branches during hepatic operations, such as isolated or combined caudate lobectomy.     

Intrahepatic venous anastomoses with a focus on the middle hepatic vein anastomoses in normal human livers: anatomical study on liver corrosion casts

Purpose

The aim of this study is to present the anatomical data about intrahepatic venous anastomoses found in normal human livers. The focus is on the middle hepatic vein (MHV) anastomoses, because their existence or non-existence could be of crucial importance in tumour resections as well as in split or living donor liver transplantations.

Materials and methods

The frequency of livers with intrahepatic venous anastomoses was determined on 164 corrosion casts and the diameter of each anastomosis was measured. Additionally, the type of connection and the position within the liver (liver segment) was determined for each MHV anastomosis.

Results

Intrahepatic venous anastomoses were found in 46 % (75/164), whereas MHV anastomoses were found in 28 % (44/164) of liver casts. Most commonly (39/44), MHV had anastomotic connections with the right hepatic vein (RHV), and also with the inferior RHV, the left hepatic vein and the short subhepatic vein. In more than three quarters of liver casts, MHV–RHV anastomoses were found in liver segment 8; in 45 % of cases, there was more than one anastomosis in this liver segment. The diameter of MHV–RHV anastomoses found in segment 8 was ≥1 mm in 90.6 % of cases.

Conclusion

As MHV anastomoses were present in more than a quarter of all examined liver casts, we believe that detailed anatomical data presented in this article, together with up to date radiologic technics which enable even 3D reconstruction of venous anastomoses in the liver, could contribute to the clinician’s decisions when planning surgical procedures.     

Complex anomalies of type 1 proatlantal intersegmental artery and aortic arch variations

Purpose

We report a case of type 1 proatlantal intersegmental artery (PIA) associated with multiple anomalies of the aortic arch, and discuss the possible embryonic mechanism and clinical importance of the multiple cerebrovascular variants in this patient.

Methods

A 65-year-old woman with dizziness underwent cerebral magnetic resonance (MR) imaging and head and neck MR angiography using a 3-tesla scanner and computed tomography (CT) angiography using a 64-slice multidetector CT scanner.

Results

MR and CT angiography demonstrated an aneurysm of the distal end of the azygos anterior cerebral arteries and hypoplasia of the proximal right vertebral artery (VA) with an anastomotic artery, between the right internal carotid artery (ICA) and distal right VA that passed through the foramen magnum, indicating a type 1 PIA. She also demonstrated an aberrant right subclavian artery (ARSA) with hypoplasia of the right VA, and the left VA arose directly from the aortic arch.

Conclusion

To our knowledge, this is the first report of a type 1 PIA associated with multiple vascular anomalies of the aortic arch, such as ARSA and origin of the left VA from the arch. In cases of persistent anastomoses between the carotid and vertebrobasilar arteries, such as PIAs, imaging examination should include the aortic arch to identify associated vascular variations.     

Depression,Posttraumatic Stress,and Risk Factors Following Spinal Cord Injury

Background

Chronic depression and posttraumatic stress have been frequently observed in populations of accident victims with spinal cord injuries. Studies suggest that various risk factors contribute to the development and maintenance of these symptoms.

Purpose

This study assessed psychopathology around 4 years post-discharge in a German sample of 102 participants with spinal cord injuries.

Methods

A wide range of sociodemographic, clinical, and psychological variables was investigated with regard to their association with psychopathology.

Results

Approximately half of the patients (46.1 %) retrospectively reported clinically relevant depressive symptoms immediately post-discharge and 12.7 % exhibited scores indicative of a present depressive disorder. In addition, 8.8 % retrospectively reported clinically relevant symptoms of posttraumatic stress disorder (PTSD) after discharge from the hospital and 2 % were currently identified with chronic PTSD symptomatology. Time since injury and negative trauma-related appraisals of the self were strongly related to current psychopathology.

Conclusion

Depressive reactions and posttraumatic distress may commonly occur after spinal injuries but will usually improve over time. It might be useful to routinely arrange follow-up contacts post-discharge in order to timely identify patients who are at risk of developing chronic psychopathology and require intervention.     

The influence of aerobic fitness on the recovery of peak power output

Purpose

The aims of this study were to evaluate the recovery kinetics of peak power output (PPO) following a maximal sprint, and to evaluate the influence of aerobic fitness on that recovery process.

Methods

On separate occasions, 16 well-trained men (age: 21 ± 3 years; height: 1.84 ± 0.05 m; and body mass: 78.8 ± 7.8 kg) performed a 30 s maximal sprint on a cycle ergometer, followed by a predetermined stationary rest period (5, 10, 20, 40, 80, and 160 s) and a subsequent 5 s sprint to determine PPO recovery kinetics. On another occasion, \({\dot V}{{\rm O}_{2}}\) was monitored during recovery from a 30 s sprint to provide a comparison with the recovery of PPO. Finally, subjects completed a \({\dot V}{{\rm O}_{2{\rm max}}}\) test to evaluate the influence of aerobic fitness on the recovery of PPO.

Results

Despite following similar time courses (F = 0.36, p = 0.558), and being well described by double-exponential models, the kinetic parameters of PPO and \({\dot V}{{\rm O}_{2}}\) in recovery were significantly different (p < 0.05). There was no significant relationship (r = 0.15; p = 0.578) between \({\dot V}{\rm O}_{2{\rm max}}\) and the time to achieve 50 % recovery of PPO. Moreover, there was no difference (p = 0.61) between the recovery kinetics of participants classified according to their \({\dot V}{\rm O}_{2{\rm max}}\) (59.4 ± 1.3 vs 48.5 ± 2.2 ml·kg^?1·min^?1).

Conclusion

Despite similar overall recovery kinetics, \({\dot V}{{\rm O}_{2}}\) and PPO show differences in key model parameters. Moreover, the recovery of PPO does not appear to be affected by aerobic fitness.     

Accessory navicular bone incidence in Chinese patients: a retrospective analysis of X-rays following trauma or progressive pain onset

Background

Optimal treatment of symptomatic accessory navicular bones, generally asymptomatic ‘extra’ ossicles in the front interior ankle, remains debated.

Objective

Incidence and type of accessory navicular bones in Chinese patients were examined as a basis for improving diagnostic and treatment standards.

Methods

Accessory navicular bones were retrospectively examined in 1,625 (790 men and 835 women) patients with trauma-induced or progressive symptomatic ankle pain grouped by gender and age from August 2011 to May 2012. Anterior–posterior/oblique X-ray images; presence; type; affected side; modified Coughlin’s classification types 1, 2A, 2B, and 3; and subgroups a–c were recorded.

Results

Accessory navicular bones were found in 329 (20.2 %) patients (143 men and 186 women; mean age, 47.24 ± 18.34, ranging 14–96 years). Patients aged 51–60 exhibited most accessory navicular bones (29.7 %), with risk slightly higher in women and generally increasing from minimal 10.9 % at ages 11–20 to age 51 and thereafter declining to 0.4 % by age 90. The incidence was 41.6 % for Type 1 (Type 1a: 9.1 %, Type 1b: 15.5 %, and Type 1c: 19.4 %), 36.8 % for Type 2 (Type 2Aa: 2.1 %, Type 2Ab: 13.7 %, Type 2Ac: 5.1 %, Type 2Ba: 2.1 %, 2Bb: 2.1 %, and 2Bc: 11.6 %), and 21.6 % for Type 3 (Type 3a: 4.5 %, Type 3b: 14 %, and Type 3c: 3.0 %).

Conclusions

Approximately one-fifth (20.3 %) of ankle pain patients exhibited accessory navicular bones, with Type 2 most common and middle-aged patients most commonly affected. Thus, accessory navicular bones may be less rare than previously thought, underlying treatable symptomatic conditions of foot pain and deformity.     

Short-term high-intensity interval and continuous moderate-intensity training improve maximal aerobic power and diastolic filling during exercise

Purpose

This study examined the effects of short-term high-intensity interval training (HIT) and continuous moderate-intensity training (CMT) on cardiac function in young, healthy men.

Methods

Sixteen previously untrained men (mean age of 25.1 ± 4.1 years) were randomly assigned to HIT and CMT (n = 8 each) and assessed before and after six sessions over a 12-day training period. HIT consisted of 8–12 intervals of cycling for 60 s at 95–100 % of pre-training maximal aerobic power ( $\dot{V}$ O_2max), interspersed by 75 s of cycling at 10 % $\dot{V}$ O_2max. CMT involved 90–120 min of cycling at 65 % pre-training $\dot{V}$ O_2max. Left ventricular (LV) function was determined at rest and during submaximal exercise (heart rate ~105 bpm) using two-dimensional and Doppler echocardiography.

Results

Training resulted in increased calculated plasma volume (PV) in both groups, accompanied by improved $\dot{V}$ O_2max in HIT (HIT: from 39.5 ± 7.1 to 43.9 ± 5.5 mL kg^?1 min^?1; CMT: from 39.9 ± 5.9 to 41.7 ± 5.3 mL kg^?1 min^?1; P < 0.001). Resting LV function was not altered. However, increased exercise stroke volume (P = 0.02) and cardiac output (P = 0.02) were observed, secondary to increases in end-diastolic volume (P < 0.001). Numerous Doppler and speckle tracking indices of diastolic function were similarly enhanced during exercise in both training groups and were related to changes in PV.

Conclusion

Short-term HIT and CMT elicit rapid improvements in $\dot{V}$ O_2max and LV filling without global changes in cardiac performance at rest.     

The validity of the Moxus Modular metabolic system during incremental exercise tests: impacts on detection of small changes in oxygen consumption

Purpose

We investigated the accuracy of the Moxus Modular Metabolic System (MOXUS) against the Douglas Bag Method (DBM) during high-intensity exercise, and whether the two methods agreed when detecting small changes in $\dot{V}{\text{O}}_{2}$ between two consecutive workloads ( $\Delta {\dot{{V}}\text{O}}_{ 2}$ ).

Methods

Twelve trained male runners performed two maximal incremental running tests while gas exchange was analyzed simultaneously by the two systems using a serial setup for four consecutive intervals of 30 s on each test. Comparisons between methods were performed for $\dot{V}{\text{O}}_{2}$ , ${\dot{{V}}}_{\text{E}}$ , fractions of expired O₂ (FeO₂) and CO₂ (FeCO₂) and $\Delta {\dot{{V}}\text{O}}_{ 2}$ .

Results

The MOXUS produced significant higher (mean ± SD, n = 54) readings for $\dot{V}{\text{O}}_{2}$ (80 ± 200 mL min^?1, p = 0.005) and ${\dot{{V}}}_{\text{E}}$ (2.9 ± 4.2 L min^?1, p < 0.0001), but not FeO₂ (?0.01 ± 0.09). Log-transformed 95 % limits of agreement for readings between methods were 94–110 % for $\dot{V}{\text{O}}_{2}$ , 97–108 % for $\dot{V}_{\text{E}}$ and 99–101 % for FeO₂. $\Delta \dot{V}{\text{O}}_{2}$ for two consecutive measurements was not different between systems (120 ± 110 vs. 90 ± 190 mL min^?1 for MOXUS and DBM, respectively, p = 0.26), but agreement between methods was very low (r = 0.25, p = 0.12).

Discussion

Although it was tested during high-intensity exercise and short sampling intervals, the MOXUS performed within the acceptable range of accuracy reported for automated analyzers. Most of the differences between equipments were due to differences in $\dot{V}_{\text{E}}$ . Detecting small changes in $\dot{V}{\text{O}}_{2}$ during an incremental test with small changes in workload, however, might be beyond the equipment’s accuracy.     

Hat die Ausschreibung von CPAP-Geräten einen Einfluss auf die Compliance und Abbruchrate bei Patienten mit obstruktivem Schlafapnoesyndrom?

Background and objectives

The compliance of CPAP therapy in patients with obstructive sleep apnea syndrome is variable. Many factors have a significant influence. The new bidding procedure of CPAP devices by insurance companies is a new factor in this area. The goal of this study was to investigate what influence this additional factor has on the compliance and drop-out rate.

Patients and methods

All patients who received a CPAP device in our sleep laboratory in 2009 were included in the study. Two groups were formed: patients with bidding procedure (group A) and patients without (group B). All patients received a questionnaire and an appointment in the sleep laboratory. Patients were compared regarding epidemiological and sleep medicine aspects while using the device.

Results

A total of 87 (group A) and 93 (group B) patients were included. The observation time required 622–966 days (mean 692.6 days). The data at the beginning of the study were comparable. The drop-out rate in group A was higher than in group B (29.9?% vs 22.6?%). Statistical significance was not accomplished (p?=?0.072).

Conclusions

The bidding procedure for CPAP devices might have negative effects for the drop-out rate of the therapy; however, further investigations are needed.     

Early gain in body mass with continuous positive airway pressure therapy for obstructive sleep apnea

Study objectives

Many clinicians believe that continuous positive airway pressure (CPAP) therapy of obstructive sleep apnea (OSA) is associated with a decrease in body mass, but to date, studies generally suggest long-term stability in body mass after 1 year. We have seen body mass increase after 4 weeks of treatment with CPAP in most patients with OSA. In this study, we test the hypothesis that therapy of OSA with CPAP produces a short-term gain in body mass, and look for physiological correlates to suggest an underlying mechanism.

Methods

Retrospective analysis of 218 consecutive patients treated for sleep apnea at a community-based sleep center.

Results

A total of 152 patients met the criteria for study conclusion. After 1 month of CPAP treatment, 119 subjects (78%) gained mass, including 81% of men and 73% of women. As a group, subjects on CPAP gained 1.4±2.5 kg (mean±SD). The Epworth Sleepiness Scale was reduced after 1 month of CPAP therapy. There was no correlation between gain in body mass and measured parameters. A subgroup of 71 patients remained on therapy. They demonstrated a gain in mass at 4 weeks, which did not persist at 6 months.

Conclusions

CPAP treatment of OSA is associated with gain in body mass at 1 month but not 6 months of therapy. The nature of this gain in mass remains unknown. We believe the gain is due to increased vascular volume, and might represent an early marker of physiological benefit of CPAP. This article includes a review of potential mechanisms for early increase in body mass with CPAP.     

Cycling time to failure is better maintained by cold than contrast or thermoneutral lower-body water immersion in normothermia

Purpose

To examine the effects of four commonly used recovery treatments applied between two bouts of intense endurance cycling on the performance of the second bout in normothermia (~21 °C).

Methods

Nine trained men completed two submaximal exhaustive cycling bouts (Ex1 and Ex2: 5 min at ~50 % ${\dot{\text{V}}\text{O}}_{2}$ peak, followed by 5 min at ~60 % ${\dot{\text{V}}\text{O}}_{2}$ peak and then ~80 % ${\dot{\text{V}}\text{O}}_{2}$ peak to failure) separated by 30 min of (a) cold water immersion at 15 °C (C15), (b) contrast water therapy alternating 2.5 min at 8 °C and 2.5 min at 40 °C (CT), (c) thermoneutral water immersion at 34 °C (T34) and (d) cycling at ~40 % ${\dot{\text{V}}\text{O}}_{2}$ peak (AR).

Results

Exercise performance, cardiovascular and metabolic responses during Ex1 were similar among all trials. However, time to failure (~80 % ${\dot{\text{V}}\text{O}}_{2}$ peak bout) during Ex2 was significantly (P < 0.05) longer in C15 (18.0 ± 1.6) than in CT (14.5 ± 1.5), T34 (12.4 ± 1.4) and AR (10.6 ± 1.0); and it was also longer (P < 0.05) in CT than AR. Core temperature and heart rate were significantly (P < 0.05) lower during the initial ~15 min of Ex2 during C15 compared with all other conditions but they reached similar levels at the end of Ex2.

Conclusions

A 30 min period of C15 was more beneficial in maintaining intense submaximal cycling performance than CT, T34 and AR; and CT was also more beneficial than T34 and AR. These effects were not mediated by the effect of water immersion per se, but by the continuous (C15) or intermittent (CT) temperature stimulus (cold) applied throughout the recovery.     

Morphometric variability of pyramidalis muscle and its clinical significance

Purpose

The goal of the study is to analyze the morphometric diversity of the pyramidalis muscle (PM) and to evaluate how it is affected by gender and side of occurrence.

Materials and methods

Ninety-six (50 male and 46 female) formalin-embalmed Greek cadavers were dissected.

Results

The PM was present in 93.8 %, usually bilaterally (79.2 %) than unilaterally (14.6 %) (p = 0.003) and more frequently in females (91.3 %) than in males (68 %) (p = 0.0001). Side symmetry was detected. The mean length of PM in males and females was 8.37 ± 2.80 and 6.18 ± 1.64 cm on the right and 7.50 ± 2.66 and 6.56 ± 1.68 cm on the left side. Male predominance existed on the right and left-sided PM lengths (p = 0.0001 and p = 0.054). The mean width of the right-sided PMs in males and females was 1.61 ± 0.55 and 1.50 ± 0.44 cm and the left-sided 1.56 ± 0.53 and 1.55 ± 0.38 cm without gender dimorphism. The positive correlation between the PM length and width indicates a symmetrical muscle augmentation on the two dimensions.

Conclusions

The study demonstrates that the PM is almost constant in Greeks. Among populations the muscle morphometric variability, its clinical significance and its variable uses will help surgeons when intervening in the lower abdominal wall.

     

Posterior tympanotomy is a riskier procedure in chronic otitis media than in a normal mastoid: a high-resolution computed tomography study

Purpose

The aim of our study was to compare the difficulty in performing a posterior tympanotomy in chronic otitis media (COM) versus the same procedure in a normal mastoid.

Materials and methods

The study included 122 patients who underwent tympanomastoidectomy for unilateral chronic otitis media with contralateral normal mastoid pneumatization. We evaluated the anatomical relationships between the mastoid segment and neighboring structures by analyzing axial temporal bone computed tomography scans. A vertical line (line A) was drawn tangential to the most lateral end of the posterior semicircular canal (point A). Three distances were measured: the distance (D1) between the point A and the most lateral end of the mastoid segment of the facial nerve (point B), the distance (D2) between the line A and the point B, and the distance (D3) between the point B and the posterior end of the bony annulus of the external auditory canal.

Results

The average measurements of D1 and D3 were 3.79 ± 0.55 and 2.63 ± 0.51 mm, respectively, in the normal mastoid ears and 3.47 ± 0.59 and 2.35 ± 0.44 mm, respectively, in the COM ears. The measurements of D1 and D3 were statistically shorter in the COM ears than in the normal ears.

Conclusions

These findings suggest that the facial recess in COM may be narrower than in a normal mastoid and that performing a posterior tympanotomy may be riskier in COM than in a normal mastoid due to the potential for injury to the neighboring structures and the facial nerve.

     

Faster \dot{V}{\text{O}}_{ 2} kinetics after eccentric contractions is explained by better matching of O2 delivery to O2 utilization

Purpose

This study examined the impact of eccentric exercise-induced muscle damage on the rate of adjustment in muscle deoxygenation and pulmonary O₂ uptake ( \(\dot{V}{\text{O}}_{{2{\text{p}}}}\) ) kinetics during moderate exercise.

Methods

Fourteen males (25 ± 3 year; mean ± SD) completed three step transitions to 90 % θ_L before (Pre), 24 h (Post24) and 48 h after (Post48) eccentric exercise (100 eccentric leg-press repetitions with a load corresponding to 110 % of the participant’s concentric 1RM). Participants were separated into two groups: phase II \(\dot{V}{\text{O}}_{{2{\text{p}}}}\) time constant (τ \(\dot{V}{\text{O}}_{{2{\text{p}}}}\) ) ≤ 25 s (fast group; n = 7) or τ \(\dot{V}{\text{O}}_{{2{\text{p}}}}\)  > 25 s (slow group; n = 7). \(\dot{V}{\text{O}}_{{2{\text{p}}}}\) and [HHb] responses were modeled as a mono-exponential.

Results

In both groups, isometric peak torque (0°/s) at Post24 was decreased compared to Pre (p < 0.05) and remained depressed at Post48 (p < 0.05). τ \(\dot{V}{\text{O}}_{{2{\text{p}}}}\) was designed to be different (p < 0.05) at Pre between the Fast (τ \(\dot{V}{\text{O}}_{{2{\text{p}}}}\) ; 19 ± 4 s) and Slow (32 ± 6 s) groups. There were no differences among time points (τ \(\dot{V}{\text{O}}_{{2{\text{p}}}}\) : Pre, 19 ± 4 s; Post24, 22 ± 3 s; Post48, 20 ± 4 s) in the Fast group. In Slow, there was a speeding (p < 0.05) from the Pre (32 ± 6 s) to the Post24 (25 ± 6) but not Post48 (31 ± 6), resulting in no difference (p > 0.05) between groups at Post24. This reduction of τ \(\dot{V}{\text{O}}_{{2{\text{p}}}} \,\) was concomitant with the abolishment (p < 0.05) of an overshoot in the [HHb]/ \(\dot{V}{\text{O}}_{{2{\text{p}}}}\) ratio.

Conclusion

We propose that the sped \(\dot{V}{\text{O}}_{{2{\text{p}}}}\) kinetics observed in the Slow group coupled with an improved [HHb]/ \(\dot{V}{\text{O}}_{{2{\text{p}}}}\) ratio suggest a better matching of local muscle O₂ delivery to O₂ utilization following eccentric contractions.