Preserving the Nipple Projection in Breast Reduction with the Free Nipple-Areolar Graft Technique: Purse-String Suture.

BACKGROUND: Breast reduction with the free nipple-areolar graft (FNG) technique has disadvantages such as loss of nipple projection, loss of nipple sensation, and depigmentation of the nipple-areolar complex. In this study, patients in whom a purse-string (PS) suture was used in the center of the de-epithelialized area to prevent loss of nipple projection were compared with patients who underwent the conventional method. METHODS: A retrospective analysis of the patients who underwent breast reduction with the FNG was conducted in our department. Patients were divided into two groups according to the FNG placement. In the PS suture method group, a 1-cm-diameter circumferential suture was placed with a 5-0 Monocryl® (poliglecaprone 25) suture to gain a 6-mm-nipple projection. In the conventional method group, the FNG was placed directly over the de-epithelized area. Graft viability was evaluated after 3 weeks postoperatively. The final nipple projection and depigmentation were evaluated after 6 months postoperatively. The results were evaluated with statistical tests. RESULTS: The number of patients with the conventional method was 10, and the PS suture method was 12. There was no statistically significant difference between two groups regarding graft loss and depigmentation (p > 0.05). Nipple projection was significantly higher in the PS method group (p < 0.05). CONCLUSION: We observed that PS circumferential suture made an acceptable nipple projection compared to the conventional method in breast reduction with the FNG technique. Since the method is easy to apply and has relatively low risk, it would contribute to clinical practice. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Pronator quadratus musculo-osseous free flap for wide hard palatal defect reconstruction: An anatomical study.

Wide hard palate defects include congenital and acquired defects that are six square centimeters or larger in size. Obturator prostheses and autologous soft tissue transfers have been used to reconstruct palatal defects. This study aims to repair wide, hard palatal defects by using a pronator quadratus musculo-osseous free flap to achieve subtotal reconstruction. Seventeen formalin-fixed cadavers were dissected. Free musculo-osseous pronator quadratus flaps were prepared after a 12 cm curvilinear volar skin incision. Standard 30 × 23 mm (690 ± 52.12 mm2) hard palate defects were made by chisels and saws. A subcutaneous tunnel was created between the mandibular edge cross point of the facial vessels and the retromolar trigone through the subcutaneous to the superficial musculoaponeurotic system by dissection. Area measurements of the pedicle and palate defects were performed by the ImageJ program (National Institutes of Health, Bethesda, MD, USA) on drawings over an acetate layer of materials. Mandibular distances of gonion-facial vessel cross point (a), gonion-gnathion (m), and facial vessels' cross point-retromolar entrance point (h) were measured. Ratios of h/m and a/m were calculated. The mean pronator quadratus area was 2349.39 ± 444.05 mm2, and the arterial pedicle pronator quadratus diameter was 2.32 ± 0.34 mm. The mean pedicle length of the pronator quadratus was 117.13 ± 8.10 mm. Study results showed that musculo-osseous pronator quadratus flaps' bone and muscle parts perfectly fit on the defects in all cadavers. Pronator quadratus musculo-osseous flap is a feasible surgical option for wide, hard palatal defect reconstruction strategies.

Knowledge, Attitude, Perceptions, and Concerns of Pregnant Women Regarding the Influenza Vaccination in Kocaeli, Turkey.

Introduction In order to better understand the barriers to influenza vaccination, we have designed a study to investigate pregnant women's knowledge, attitude, perceptions, and concerns towards the inactivated influenza vaccine. Materials and methods In this prospective study, carried out between July 1, 2019, and December 31, 2019, 252 pregnant women (≥12 weeks of gestational age), who had consented to be enrolled in the study, were asked to complete an interviewer-administered questionnaire during their stay in the hospital ward. Results The lack of information about influenza vaccines (59.4%) was in the first rank among the reasons for personal and parental vaccine rejection. Most (65.1%) pregnant women either did not believe in or had doubts about the efficiency of the influenza vaccine during gestation. Most of them (80.9%) either were not sure about or did not have much confidence in the prenatally inoculated vaccine's ability to protect their babies postnatally. Some (25.6%) participants attributed their vaccinal unwillingness to fear of adverse effects, and some (11.5%) deemed gestational influenza immunization unnecessary because of their tendency to underestimate the grave consequences of influenza contracted by infants within the first six months of life. The higher the education level, the higher was the knowledge of and the willingness to be immunized against influenza. Discussion It is known that about one-third of pregnant women in Turkey have never heard of the influenza vaccine. Unawareness of influenza vaccination in pregnancy is significantly related to vaccine uptake in Japan. Patient education on knowledge of influenza and influenza vaccination has a booster effect on vaccination rates. Had the influenza vaccine been routinely administered to pregnant women in Turkey, the lives of the majority of the women who died of influenza in the influenza A (H1N1) pandemic in 2009 would have been saved. Low-risk perception is quoted as one of the main reasons for influenza vaccine refusal during pregnancy, which was also the case in our study. Concordant with the current literature, the education level and household income were correlated with the level of influenza vaccination uptake. Pregnant women's fear of adverse effects of the influenza vaccine might extend to the fear of birth defects. Conclusion The acceptance of influenza vaccines by pregnant women is a consequence of complex interactions of various factors. Giving necessary information to pregnant women is one of the most important factors that can increase influenza vaccine uptake. For this reason, it should be ensured that the efficacy and safety data of the influenza vaccine are more widely included in vocational training activities of health personnel and in prenatal care textbooks and guidelines.

Neurovascular anatomy of pronator quadratus for reanimation of blepharoptosis.

PURPOSE: Pronator quadratus (PQ) is a quadrilateral muscle on a volar distal side of the forearm. The purpose of this study was to establish a novel surgical technique for reanimation of the upper eyelid for severe ptosis using PQ functional free muscle flap. METHODS: The current study is a cadaveric study, designed to assess a PQ free flap transfer that lies between the frontalis muscle and the upper eyelid. Fourteen PQ from fourteen embalmed cadavers were dissected, and their neurovascular pedicles were isolated. Then they were transferred to the area on the contralateral side between the frontalis muscle and upper eyelid tarsal cartilage. Measurements of the PQ flap, antebrachial region, orbitofrontal region, recipient vessels, and motor nerve were performed using a caliper. The extendibility of neurovascular pedicles was evaluated by measurements of lengths. In addition, the diameter of PQ flap vascular pedicle vessels was compared with recipient vessels. RESULTS: The mean width of the proximal border of PQ was 41.92 ± 2.05 mm and the distal border of the PQ was 42.84 ± 4.04 mm. The mean PQ artery (type II, Mathes-Nahai flap classification) length was found to be 117.72 ± 7.77 mm. The mean diameter of the anterior interosseous nerve was 1.89 ± 0.08 mm. The mean diameter of the uppermost branch of the frontal branch of the facial nerve was 1.18 ± 0.25 mm. The length and diameter of neurovascular pedicles of muscle flaps were adequate for microvascular anastomoses and neurorrhaphy. CONCLUSIONS: The results of this anatomical study demonstrate that the PQ free flap transfer has anatomical features that are suitable and compatible with the surgical treatment of blepharoptosis.

Prevalence, Determinants, and Consequences of Vestibular Hypofunction. Results From the KORA-FF4 Survey.

Objective: Uni- or bilateral vestibular hypofunction (VH) impairs balance and mobility, and may specifically lead to injury from falls and to disability. The extent of this problem in the general population is still unknown and most likely to be underestimated. Objective of this study was to determine the prevalence, determinants, and consequences of VH in the general population. Methods: Data originates from the cross-sectional second follow-up (FF4) in 2013/14 of the KORA (Cooperative Health Research in the Region of Augsburg)-S4 study (1999-2001) from Southern Germany. This was a random sample of the target population consisting of all residents of the region aged 25-74 years in 1999. We included all participants who reported moderate or severe vertigo or dizziness during the last 12 months and a random sub-sample of participants representative for the general population without vertigo or dizziness during the last 12 months were tested. VH was assessed with the Video-Head Impulse Test (vHIT). Trained examiners applied high-acceleration, small-amplitude passive head rotations ("head impulses") to the left and right in the plane of the horizontal semicircular canals while participants fixated a target straight ahead. During head impulses, head movements were measured with inertial sensors, eye movements with video-oculography (EyeSeeCam vHIT). Results: A total of 2,279 participants were included (mean age 60.8 years, 51.6% female), 570 (25.0%) with moderate or severe vertigo or dizziness during the last 12 months. Of these, 450 were assessed with vHIT where 26 (5.8%) had unilateral VH, and 16 (3.6%) had bilateral VH. Likewise, 190 asymptomatic participants were tested. Of these 5 (2.6%) had unilateral VH, and 2 (1.1%) had bilateral VH. Prevalence of uni- or bilateral VH among tested symptomatic participants was 2.4% in those < 48 years, and 32.1% in individuals aged 79 and over. Age-adjusted prevalence was 6.7% (95% CI 4.8%; 8.6%). VH was associated with worse health, falls, hearing loss, hearing impairment, and ear pressure. Conclusion: VH may affect between 53 and 95 million adults in Europe and the US. While not all affected persons will experience the full spectrum of symptoms and consequences, adequate diagnostic and therapeutic measures should become standard of care to decrease the burden of disease.

A single retinal circuit model for multiple computations.

Vision is dependent on extracting intricate features of the visual information from the outside world, and complex visual computations begin to take place as soon as at the retinal level. In multiple studies on salamander retinas, the responses of a subtype of retinal ganglion cells, i.e., fast/biphasic-OFF ganglion cells, have been shown to be able to realize multiple functions, such as the segregation of a moving object from its background, motion anticipation, and rapid encoding of the spatial features of a new visual scene. For each of these visual functions, modeling approaches using extended linear-nonlinear cascade models suggest specific preceding retinal circuitries merging onto fast/biphasic-OFF ganglion cells. However, whether multiple visual functions can be accommodated together in a certain retinal circuitry and how specific mechanisms for each visual function interact with each other have not been investigated. Here, we propose a physiologically consistent, detailed computational model of the retinal circuit based on the spatiotemporal dynamics and connections of each class of retinal neurons to implement object motion sensitivity, motion anticipation, and rapid coding in the same circuit. Simulations suggest that multiple computations can be accommodated together, thereby implying that the fast/biphasic-OFF ganglion cell has potential to output a train of spikes carrying multiple pieces of information on distinct features of the visual stimuli.

Preventing opioid-induced nausea and vomiting: Rest your head and close your eyes?

Although opioid-induced nausea and vomiting (OINV) is common and debilitating, its mechanism is still unclear. Recently, we suggested that opioids affect semicircular canal function and that this leads to a mismatch between canal input and other sensory information during head motion, which triggers OINV. Here, we assess if visual input is relevant for this mismatch. In a randomized-controlled crossover study 14 healthy men (26.9±3.4 years, mean±SD) were tested twice, once blindfolded and once with eyes open, with at least one-day washout. The opioid remifentanil was administered intravenously (0.15 µg/kg/min) for 60 minutes. After a thirty-minutes resting period, subjects' head and trunk were passively moved. Nausea was rated before remifentanil start (T0), before the movement intervention (T30) and after 60 minutes (T60) of administration. At rest (T0, T30), median nausea ratings were zero whether subjects were blindfolded or not. Movement triggered nausea independently of visual input (nausea rating 1.5/3.0 (median/interquartile range) in the blindfolded, 2.5/6 in the eyes-open condition, χ2(1) = 1.3, p = 0.25). As movement exacerbates OINV independently of visual input, a clash between visual and semicircular canal information is not the relevant trigger for OINV. To prevent OINV, emphasis should be put on head-rest, eye-closure is less important.

Opioid-Induced Nausea Involves a Vestibular Problem Preventable by Head-Rest.

BACKGROUND AND AIMS: Opioids are indispensable for pain treatment but may cause serious nausea and vomiting. The mechanism leading to these complications is not clear. We investigated whether an opioid effect on the vestibular system resulting in corrupt head motion sensation is causative and, consequently, whether head-rest prevents nausea. METHODS: Thirty-six healthy men (26.6 ± 4.3 years) received an opioid remifentanil infusion (45 min, 0.15 µg/kg/min). Outcome measures were the vestibulo-ocular reflex (VOR) gain determined by video-head-impulse-testing, and nausea. The first experiment (n = 10) assessed outcome measures at rest and after a series of five 1-Hz forward and backward head-trunk movements during one-time remifentanil administration. The second experiment (n = 10) determined outcome measures on two days in a controlled crossover design: (1) without movement and (2) with a series of five 1-Hz forward and backward head-trunk bends 30 min after remifentanil start. Nausea was psychophysically quantified (scale from 0 to 10). The third controlled crossover experiment (n = 16) assessed nausea (1) without movement and (2) with head movement; isolated head movements consisting of the three axes of rotation (pitch, roll, yaw) were imposed 20 times at a frequency of 1 Hz in a random, unpredictable order of each of the three axes. All movements were applied manually, passively with amplitudes of about ± 45 degrees. RESULTS: The VOR gain decreased during remifentanil administration (p<0.001), averaging 0.92 ± 0.05 (mean ± standard deviation) before, 0.60 ± 0.12 with, and 0.91 ± 0.05 after infusion. The average half-life of VOR recovery was 5.3 ± 2.4 min. 32/36 subjects had no nausea at rest (nausea scale 0.00/0.00 median/interquartile range). Head-trunk and isolated head movement triggered nausea in 64% (p<0.01) with no difference between head-trunk and isolated head movements (nausea scale 4.00/7.25 and 1.00/4.5, respectively). CONCLUSIONS: Remifentanil reversibly decreases VOR gain at a half-life reflecting the drug's pharmacokinetics. We suggest that the decrease in VOR gain leads to a perceptual mismatch of multisensory input with the applied head movement, which results in nausea, and that, consequently, vigorous head movements should be avoided to prevent opioid-induced nausea.

The effect of vestibulo-ocular reflex deficits and covert saccades on dynamic vision in opioid-induced vestibular dysfunction.

Patients with bilateral vestibular dysfunction cannot fully compensate passive head rotations with eye movements, and experience disturbing oscillopsia. To compensate for the deficient vestibulo-ocular reflex (VOR), they have to rely on re-fixation saccades. Some can trigger "covert" saccades while the head still moves; others only initiate saccades afterwards. Due to their shorter latency, it has been hypothesized that covert saccades are particularly beneficial to improve dynamic visual acuity, reducing oscillopsia. Here, we investigate the combined effect of covert saccades and the VOR on clear vision, using the Head Impulse Testing Device-Functional Test (HITD-FT), which quantifies reading ability during passive high-acceleration head movements. To reversibly decrease VOR function, fourteen healthy men (median age 26 years, range 21-31) were continuously administrated the opioid remifentanil intravenously (0.15 µg/kg/min). VOR gain was assessed with the video head-impulse test, functional performance (i.e. reading) with the HITD-FT. Before opioid application, VOR and dynamic reading were intact (head-impulse gain: 0.87±0.08, mean±SD; HITD-FT rate of correct answers: 90±9%). Remifentanil induced impairment in dynamic reading (HITD-FT 26±15%) in 12/14 subjects, with transient bilateral vestibular dysfunction (head-impulse gain 0.63±0.19). HITD-FT score correlated with head-impulse gain (R = 0.63, p = 0.03) and with gain difference (before/with remifentanil, R = -0.64, p = 0.02). One subject had a non-pathological head-impulse gain (0.82±0.03) and a high HITD-FT score (92%). One subject triggered covert saccades in 60% of the head movements and could read during passive head movements (HITD-FT 93%) despite a pathological head-impulse gain (0.59±0.03) whereas none of the 12 subjects without covert saccades reached such high performance. In summary, early catch-up saccades may improve dynamic visual function. HITD-FT is an appropriate method to assess the combined gaze stabilization effect of both VOR and covert saccades (overall dynamic vision), e.g., to document performance and progress during vestibular rehabilitation.

Covert anti-compensatory quick eye movements during head impulses.

BACKGROUND: Catch-up saccades during passive head movements, which compensate for a deficient vestibulo-ocular reflex (VOR), are a well-known phenomenon. These quick eye movements are directed toward the target in the opposite direction of the head movement. Recently, quick eye movements in the direction of the head movement (covert anti-compensatory quick eye movements, CAQEM) were observed in older individuals. Here, we characterize these quick eye movements, their pathophysiology, and clinical relevance during head impulse testing (HIT). METHODS: Video head impulse test data from 266 patients of a tertiary vertigo center were retrospectively analyzed. Forty-three of these patients had been diagnosed with vestibular migraine, and 35 with Menière's disease. RESULTS: CAQEM occurred in 38% of the patients. The mean CAQEM occurrence rate (per HIT trial) was 11±10% (mean±SD). Latency was 83±30 ms. CAQEM followed the saccade main sequence characteristics and were compensated by catch-up saccades in the opposite direction. Compensatory saccades did not lead to more false pathological clinical head impulse test assessments (specificity with CAQEM: 87%, and without: 85%). CAQEM on one side were associated with a lower VOR gain on the contralateral side (p<0.004) and helped distinguish Menière's disease from vestibular migraine (p = 0.01). CONCLUSION: CAQEM are a common phenomenon, most likely caused by a saccadic/quick phase mechanism due to gain asymmetries. They could help differentiate two of the most common causes of recurrent vertigo: vestibular migraine and Menière's disease.

Vestibular and cerebellar contribution to gaze optimality.

Patients with chronic bilateral vestibular loss have large gaze variability and experience disturbing oscillopsia, which impacts physical and social functioning, and quality of life. Gaze variability and oscillopsia in these patients are attributed to a deficient vestibulo-ocular reflex, i.e. impaired online feedback motor control. Here, we assessed whether the lack of vestibular input also affects feed-forward motor learning, i.e. the ability to choose optimal movement parameters that minimize variability during active movements such as combined eye-head gaze shifts. A failure to learn from practice and reshape feed-forward motor commands in response to sensory error signals to achieve appropriate movements has been proposed to explain dysmetric gaze shifts in patients with cerebellar ataxia. We, therefore, assessed the differential roles of both sensory vestibular information and the cerebellum in choosing optimal movement kinematics. We have previously shown that, in the course of several gaze shifts, healthy subjects adjust the motor command to minimize endpoint variability also when movements are experimentally altered by an increase in the head moment of inertia. Here, we increased the head inertia in five patients with chronic complete bilateral vestibular loss (aged 45.4±7.1 years, mean±standard deviation), nine patients with cerebellar ataxia (aged 56.7±12.6 years), and 10 healthy control subjects (aged 39.7±6.3 years) while they performed large (75° and 80°) horizontal gaze shifts towards briefly flashed targets in darkness and, using our previous optimal control model, compared their gaze shift parameters to the expected optimal movements with increased head inertia. Patients with chronic bilateral vestibular loss failed to update any of the gaze shift parameters to the new optimum with increased head inertia. Consequently, they displayed highly variable, suboptimal gaze shifts. Patients with cerebellar ataxia updated some movement parameters to serve the minimum variance optimality principle but inaccurately undershot the target leading to an average gaze error of 11.4±2.0°. Thus, vestibulopathy leads to gaze variability not only as a result of deficient online gaze control but also a failure in motor learning because of missing error signals. Patients with cerebellar ataxia in our setting can learn from practice-similar to recent findings in reaching movements-and reshape feed-forward motor commands to decrease variability. However, they compromise optimality with inaccurately short movements. The importance of vestibular information for motor learning implies that patients with incomplete bilateral vestibulopathy, and patients with cerebellar ataxia, should be advised to actively move their head whenever appropriate. This way, sensory error signals can be used to shape the motor command and optimize gaze shifts trial-by-trial.

Strategies of locomotor collision avoidance.

Collision avoidance during locomotion can be achieved by a variety of strategies. While in some situations only a single trajectory will successfully avoid impact, in many cases several different strategies are possible. Locomotor experiments in the presence of static boundary conditions have suggested that the choice of an appropriate trajectory is based on a maximum-smoothness strategy. Here we analyzed locomotor trajectories of subjects avoiding collision with another human crossing their path orthogonally. In such a case, changing walking direction while keeping speed or keeping walking direction while changing speed would be two extremes of solving the problem. Our participants clearly favored changing their walking speed while keeping the path on a straight line between start and goal. To interpret this result, we calculated the costs of the chosen trajectories in terms of a smoothness-maximization criterion and simulated the trajectories with a computational model. Data analysis together with model simulation showed that the experimentally chosen trajectory to avoid collision with a moving human is not the optimally smooth solution. However, even though the trajectory is not globally smooth, it was still locally smooth. Modeling further confirmed that, in presence of the moving human, there is always a trajectory that would be smoother but would deviate from the straight line. We therefore conclude that the maximum smoothness strategy previously suggested for static environments no longer holds for locomotor path planning and execution in dynamically changing environments such as the one tested here.

Optimal control of natural eye-head movements minimizes the impact of noise.

When shifting gaze to foveate a new target, humans mostly choose a unique set of eye and head movements from an infinite number of possible combinations. This stereotypy suggests that a general principle governs the movement choice. Here, we show that minimizing the impact of uncertainty, i.e., noise affecting motor performance, can account for the choice of combined eye-head movements. This optimization criterion predicts all major features of natural eye-head movements-including the part where gaze is already on target and the eye counter-rotates-such as movement durations, relative eye-head contributions, velocity profiles, and the dependency of gaze shifts on initial eye position. As a critical test of this principle, we show that it also correctly predicts changes in eye and head movement imposed by an experimental increase in the head moment of inertia. This suggests that minimizing the impact of noise is a simple and powerful principle that explains the choice of a unique set of movement profiles and segment coordination in goal-directed action.

A retinal circuit model accounting for wide-field amacrine cells.

In previous experimental studies on the visual processing in vertebrates, higher-order visual functions such as the object segregation from background were found even in the retinal stage. Previously, the "linear-nonlinear" (LN) cascade models have been applied to the retinal circuit, and succeeded to describe the input-output dynamics for certain parts of the circuit, e.g., the receptive field of the outer retinal neurons. And recently, some abstract models composed of LN cascades as the circuit elements could explain the higher-order retinal functions. However, in such a model, each class of retinal neurons is mostly omitted and thus, how those neurons play roles in the visual computations cannot be explored. Here, we present a spatio-temporal computational model of the vertebrate retina, based on the response function for each class of retinal neurons and on the anatomical inter-cellular connections. This model was capable of not only reproducing the spatio-temporal filtering properties of the outer retinal neurons, but also realizing the object segregation mechanism in the inner retinal circuit involving the "wide-field" amacrine cells. Moreover, the first-order Wiener kernels calculated for the neurons in our model showed a reasonable fit to the kernels previously measured in the real retinal neuron in situ.

Parallel inhibition of cortico-muscular synchronization and cortico-spinal excitability by theta burst TMS in humans.

OBJECTIVE: To investigate the after-effects of theta burst TMS (TBS) on cortico-muscular synchronization, and on cortico-spinal excitability, in humans. METHODS: We studied 10 healthy subjects using a continuous paradigm of TBS (cTBS), i.e. 600 pulses in 40s. Before and after the cTBS, coherence function was computed as a measure of cortico-muscular synchronization by recording electroencephalogram (EEG) from 19 scalp sites and electromyogram (EMG) from right first dorsal interosseous (FDI) muscle during the isometric contraction. In a separate experiment, motor-evoked potentials (MEPs) in response to single TMS pulses were recorded from the FDI muscle before and after the cTBS, to measure cortico-spinal excitability. RESULTS: When the cTBS was applied over the left primary motor cortex (M1), the beta-band cortico-muscular coherence for the C3 scalp site, as well as the MEP amplitude significantly decreased in 30-60 min, and then recovered to the original levels in 90-120 min. Neither sham stimulation nor cTBS applied over 2 cm posterior to M1 produced significant effects. CONCLUSIONS: cTBS-over-M1 can inhibit the cortico-muscular synchronization in parallel with the decline of cortico-spinal excitability. SIGNIFICANCE: Our results provide the first evidence that TBS can efficiently alter the functional cortico-muscular coupling in humans.