Posterior Membrane Research Articles

Restoration of Tibiofibular Kinematics with a Tricortical Screw or Suture Button Fixation After Syndesmotic Ankle Injuries

Category: Ankle, Sports, Trauma Introduction/Purpose: Anterior inferior tibiofibular ligament (AITFL), Posterior inferior tibiofibular ligament (PITFL) and Interosseous membrane (IOM) disruption is a predictive measure of residual symptoms after ankle injury. In unstable injuries, the syndesmosis is treated operatively with cortical screw fixation or a suture button apparatus. Biomechanical analyses of suture button versus cortical screw fixation methods show contradicting results regarding suture button integrity and maintenance of fixation. The objective of this study is to quantify tibiofibular joint motion in syndesmotic screw and suture button fixation models compared to the intact ankle. Methods: Five fresh-frozen human cadaveric specimens (mean age 58 yrs.; range 38-73 yrs.) were tested using a 6-degree-of- freedom robotic testing system. The tibia and calcaneus were rigidly fixed to the robotic manipulator and the subtalar joint was fused. The full fibular length was maintained and fibular motion was unconstrained. Fibular motion with respect to the tibia was tracked by a 3D optical tracking system. A 5 Nm external rotation moment and 5 Nm inversion moment were applied to the ankle at 0°, 15°, and 30° plantarflexion and 10° dorsiflexion. Outcome variables included fibular medial-lateral (ML) translation, anterior-posterior (AP) translation, and external rotation (ER) in the following states: 1) intact ankle, 2) AITFL transected, 3) PITFL and IOM transected, 4) 3.5 mm cannulated tricortical screw fixation, 5) suture button fixation. An ANOVA with a post-hoc Tukey analysis was performed for statistical analysis (*p<0.05). Results: Significant differences in fibular motion were only during the inversion moment. Fibular posterior translation was significantly higher with complete syndesmosis injury compared to the intact ankle at 0°, 15°, and 30° plantarflexion and the tricortical screw at 15° and 30°. Significantly higher fibular posterior translation was observed with the suture button compared to the intact ankle at 15° and 30 plantarflexion and to the tricortical screw at 15°. ER was significantly increased with complete injury compared to the tricortical screw at 0° and 30° plantarflexion. The suture button demonstrated significantly greater ER at 0° plantarflexion and 10° dorsiflexion compared to the intact ankle. The only significant difference in ML translation exists between the tricortical screw and complete injury at 30° plantarflexion. Conclusion: The suture button did not restore physiologic motion of the syndesmosis. It only restored fibular ML translation. Significant differences in AP translation and ER persisted compared to the intact ankle. The tricortical screw restored fibular motion in all planes. No significant differences were observed compared to the intact ankle. These findings are consistent with previous studies. This study utilized a novel setup to measure unconstrained motion in a full length, intact fibula. Physicians should evaluate AP translation and ER as critical fibular motions when reconstructing the syndesmosis with suture button fixation.

The universal existence of myodural bridge in mammals: an indication of a necessary function

The “myodural bridge” was described in literatures as a dense fibrous tissue connecting the sub-occipital musculature with the spinal dura mater in human studies. Now the concept of “myodural bridge” was perceived as an exact anatomical structure presumably essential for critical physiological functions in human body, and might exist in other mammals as well. To determine the existence of the “myodural bridge” in other mammals and to lay a foundation for the functional study, we examined representatives in five different mammalian orders. Based on the anatomical dissections, P45 plastinated sections and histological sections, we found that a dense fibrous tissue connected the rectus capitisdorsalis minor and the spinal dura mater through the dorsal atlanto-occipital interspace with or without the medium of the posterior atlanto-occipital membrane. These observed connective tissues were very similar to the “myodural bridge” previously described in humans. We proposed that the “myodural bridge”, as an evolutionally conserved structure, presents in many other mammals. Moreover, we believed that the “myodural bridge” might be a homologous organ in mammals. Thus, this study could provide an insight for our understanding the physiological significance of the “myodural bridge”, especially in human.

Butterfly Cartilage Tympanoplasty Long-term Results: Excellent Treatment Method in Small and Medium Sized Perforations.

Objectives The aim of this study was to evaluate and report the long-term results of the butterfly cartilage tympanoplasty. Short-term and long-term hearing outcomes were compared according to age and perforation location as well.Methods Ninety-three patients who were diagnosed with noncomplicated chronic otitis media and underwent microscopic transcanal butterfly cartilage tympanoplasty due to anterior, posterior, and central tympanic membrane perforation were included. Age, gender, follow-up time, pre- and postoperative pure tone audiometry thresholds (both air and bone conduction), pre- and postoperative air-bone gaps (ABGs), if any residual perforation was noted.Results At the end of the follow-up period, successful closure occurred in 88 of 93 patients and success rate is 94.6%. In all patients, including those with residual perforations, the mean preoperative bone conduction threshold was 15.9 dB (range, 5 to 50 dB) among all groups whereas mean air conduction threshold was 36.4±15.1 dB (range, 10 to 90 dB) preoperatively and 28.8±14.3 dB in 6th month follow-up and 24.9±14.1 dB 24th month follow-up. Preoperative mean ABG was 22.1±7.1 dB (range, 5 to 40 dB) whereas 13.3±5.9 dB 6 months after surgery and 11.9±5.5 dB 24 months after surgery. There was a significant difference between pre- and postoperative ABG in both 6th and 24th month follow-up (P6 mo-24 mo<0.05). Furthermore, preoperative mean air conduction differed significantly from postoperative 6th and 24th month follow-up mean air conduction thresholds (P<0.05).Conclusion We suggested that butterfly cartilage tympanoplasty can be safely performed in small, moderate, and even large perforations, as the hearing outcomes and successful closure rate are similar to those of other surgical methods. Moreover, it can be performed under local anaesthesia and it has low complication rates.

Surgical treatment of «dry» forms of central chorioretinal dystrophy with the use of platelet-rich blood autoplasma

Aim. To study the impact of platelet-rich blood autoplasma on the capability of the retinal regeneration in nonexudative forms of central chorioretinal dystrophy with the use of microinvasive vitreoretinal surgery. &#x0D; Methods. Surgical treatment was performed on 14 patients with central chorioretinal dystrophy aged 29 to 87 years. The surgery technique consisted of 3-port 25+, 27 Ga vitrectomy with posterior hyaline membrane and internal limiting membrane peel with subsequent central retinal exfoliation with 38 Ga cannula and balanced sodium solution and subretinal injection to the formed in macule space 0.1-0.2 ml of platelet-rich autolplasma. &#x0D; Results. As a result of the treatment according to this technique during the long-term period after the surgery (1 to 9 months) thickness of fovea reduced to 85-150 µm in average staying stable during the whole observation period. In 9 patients pigment epithelium thickened from 24 to 38 µm in parafoveolar area and fovea area. Corrected vision in 3 patients reached 0.1, and in the rest it did not exceed 0.06, herewith, all patients noted consistently improved vision. All patients had favorable evolution of photosensitivity according to microperimetry in average from 0.1-0.5 to 8.5-11 dB with a tendency of fixation point movement from periphery to the center. &#x0D; Conclusion. Vitreoretinal surgery 25+, 27 Ga for nonexudative forms of central chorioretinal dystrophy with the use of subretinal injection of platelet-rich autoplasma is a microinvasive, safe, effective method of the treatment of such pathology improving vision characteristics and anatomical and physiological characteristics of the eye involved.

A Model for Assessing ATP Demands of Sustained High Frequency Firing

The continuous electric organ discharge (EOD) of the weakly electric fish, Eigenmannia, reflects action potentials (APs) fired by the EO's muscle-derived electrocytes. EODs enable electrosensing and communication. AP frequency is neurally controlled, with acetylcholine-gated channels (AChRs) mediating synaptic transmission. According to EOD-linked whole-fish O2 consumption (for fish with EODs between ∼300-500 Hz) ATP demand per AP grows exponentially with frequency. The unimodal task, continual firing, and simple homogeneous structure of the EO render it especially suitable for probing excitable system energetics in relation to molecular, cellular and tissue features. We develop a model, Epm, to depict currents at the electrocyte's energy-dissipating Excitable posterior membrane. In situ, 3Na/2K-ATPases (pumps) counteract the dissipation of electrocyte ENa (and EK). Using Epm we calculate AP frequency-dependent “Na+-entry budgets” for synaptic activation (pulsatile and/or steady-state, with/without noise). Comparison of Epm-calculated ATP consumption (inferred from total Na+-entry) against published EOD-linked whole-fish O2 consumption suggests that EOD-linked energy demands external to electrocytes (neuronal, circulatory etc) exceed, several-fold, those of electrocyte excitability per se. Well-understood conductance processes (as modeled by Epm) proved fully adequate for generating sustained APs (including during jamming avoidance responses) from 200-600 Hz. By contrast, although we computationally impose the equivalent of fast stimulatory variations in [ACh], even at the bottom of this frequency range the means by which synaptic transmission machinery so reliably achieves the requisite fast variations is a mystery. The simple Eigenmannia EO therefore continues to emerge as a fascinating model system for studying not only the energetics but the subcellular and broader-level dynamics of high frequency excitability.

Микроинцизионное хирургическое лечение первой стадии макулярного разрыва без витрэктомии под интраоперационным ОКТ-контролем

Purpose. To assess long-term results of the use of mechanical separation of posterior hyaloid (PH) from foveola without vitrectomy in case of macular holes in the stages Ia and Ib. Material and methods . The study included the observations in 130 patients with macular holes in the stage Ib, operated on by the same technology by the same surgeon. Posterior hyaloids membrane was separated from the foveola through 2 27Ga ports for optical fiber and a special tool. All patients before and after surgery the following analyzes were performed: anamnesis, visometry, standard perimetry, evaluation of strains on the Amsler grid, optical coherence tomography (OCT) of high-resolution using the «Cirrus» device of the Carl Zeiss Meditec company. Results. According to the optical coherence tomography of high resolution it was possible to separate completely the PH from foveola without a formation of penetrative macular holes in 98.5% of cases. Conclusions. Microinvasive mechanical separation of PH from foveola at the stage I of macular hole without staining and vitrectomy interrupts the disease process, preventing the development of penetrative macular hole, eliminates the cause of the disease.

Nd:YAG laser hyaloidotomy in the management of Premacular Subhyaloid Hemorrhage.

BackgroundPremacular subhyaloid hemorrhage results in a sudden profound loss of vision. Among the modalities for its treatment, Nd:YAG laser hyaloidotomy is a non invasive method enabling rapid drainage of the obstructed macular area and improved vision within days. This study was aimed to evaluate the efficacy, visual outcome and complications following Nd:YAG laser hyaloidotomy for premacular subhyaloid hemorrhage.MethodsPatients with premacular subhyaloid hemorrhage of more than 3 disc diameters (DD) of various etiologies, attending Tilganga Institute of Ophthalmology, Nepal from August, 2014 to February, 2015, were included. A comprehensive ocular evaluation was conducted and fundus photographs were taken to measure the size of the subhyaloid hemorrhage. Optical coherence tomography (OCT) were performed before and after treatment and on subsequent follow up visits. Fundus fluorescence angiography was done whenever necessary. Q switched Nd:YAG laser was applied to create an opening in the posterior hyaloids membrane for draining subhyaloid hemorrhage. The main outcome measures were success rate in performing hyaloidotomy, drainage of subhyaloid blood into vitreous cavity and its resorption, improvement in visual acuity, need for further intervention and postoperative complications.ResultsThere were 21 eyes of 19 patients, 17(89.48 %) male and 2(10.52 %) female. In 3, premacular subhyaloid hemorrhage was bilateral. Mean age was 41.68 ± 17.08 years and a mean duration of symptoms 15.04 days. Mean pretreatment hemorrhage was 6.27DD. Nd:YAG laser hyaloidotomy was successful in 19 eyes(86.4 %). In 2 patients, one each with Eales’ disease and retinal vein occlusion the procedure was unsuccessful, necessitating pars plana vitrectomy, while in a case with proliferative diabetic retinopathy (PDR), vitrectomy was resorted for non clearing vitreous hemorrhage. Vision improved from a median of 3/60 pre-operatively to 6/6, at 6 months follow up. At 3 months, 2 patients with Eales’ disease, one developed tractional detachment at macula while the other, an epiretinal membrane. No other complications were noted at 6 months.ConclusionNd:YAG laser hyaloidotomy is an inexpensive, effective and a safe outpatient procedure for premacular subhyaloid hemorrhage, producing rapid drainage with restoration of visual function avoiding more invasive procedures and enabling early assessment of the underlying retina. The final visual prognosis however, rests on the underlying cause of the subhyaloid hemorrhage and any accompanying retinal changes.

Assessment of posterior capsule penetrability by Pentacam Scheimpflug system

Background Posterior capsule opacification (PCO) is a common complication following cataract surgery.Establishing an objective morphological evaluation method of PCO is of important clinical significance for the prevention of PCO, but there are many problems in previous evaluating methods, and pentacam picture appears to be a useful method of assessing PCO.Recognizing the characters of different types of posterior capsule disorder and optimizing the evaluation details in Pentacam picture are helpful for us to prevent and treat PCO. Objective This study was to investigate the characters of posterior capsule disorders with Pentacam tomograms. Methods Eighty-four eyes of 82 patients were included in Zhongshan Ophthalmic Center from January to October in 2011.Slit-lamp photography and retroilluminated photography were captured after full mydriasis, and then the Pentacam imaging was performed by using 50-scan acquisition protocol, and high-resolution Pentacam tomograms were reconstructed and analyzed by Image J software.The features of the posterior capsule disorders in Pentacam tomogram were assessed, and the mean pixel-intensity at the central 4-mm diameter and 3-mm diameter was calculated and compared.The percentage of eyes being interfered by the anterior capsule in the two analyed areas was calculated.This study was approved by Zhongshan Ophthalmic Center, and uritten informed consent was obtained from each patient prior to any examination. Results The posterior capsular membranes were completely clear under the blue background in 30 eyes without posterior capsulaopathy on the Pentacam images.In 54 eyes of 52 patients with PCO, different intensities of gray patches were exhibited on the blue background in the elschnig-pearl-type PCO, and white-color non-transparence patches were seen in the fibrosis-type PCO.The mean pixel-intensity value (inter-quartile range) was 37.07 U and 38.65 U at the central 4-mm area and 3-mm area respectively, without significant difference between them (P=0.606). Capsular block syndrome was found in 3 eyes of 3 patients, showing even gray appearance on the Pentacam images and mean pixel-intensity of 12.40, 15.68 and 36.77 U at the central 3-mm area.The gray strip-like appearance on the blue background was seen in 1 eye with capsular shrinkage, and the mean pixel-intensity was 48.34 U at the central 3-mm area.The examination outcomes of 14.81% (8/54) eyes were disturbed by the anterior capsule in the central 4-mm analysis mode, but the outcomes were unaffected in central 3-mm analysis mode. Conclusions Different types of posterior capsule disorders appear particular scenery in Pentacam tomograms.There is no difference of mean pixel-intensity between the central 4-mm analysis mode and the central 3-mm analysis mode.A central 3-mm analysis mode is more available to justify the penetrability of the posterior capsule. Key words: Posterior capsule opacification; Capsule, lens; Image processing; Computer-assisted; Tomography/methods

Pediatric tracheomalacia

Tracheomalacia (TM) is defined as an increased collapsibility of the trachea due to structural anomalies of the tracheal cartilage and/or posterior membrane. Tracheomalacia has a wide range of etiologies but is most commonly present in children born with esophageal atresia and tracheal esophageal fistula. Clinical symptoms can range from minor expiratory stridor with typical barking cough to severe respiratory distress episodes to acute life-threatening events (ALTE). Although the majority of children have mild-to-moderate symptoms and will not need surgical intervention, some will need life-changing surgical treatment. This article examines the published pediatric literature on TM, discusses the details of clinical presentation, evaluation, diagnosis, and a variety of treatments.

Cerebellomedullary Cistern Delivery for AAV-Based Gene Therapy: A Technical Note for Nonhuman Primates.

Accessing cerebrospinal fluid (CSF) from the craniocervical junction through the posterior atlanto-occipital membrane via cerebellomedullary injection (also known as cisternal puncture or cisterna magna injection) has become a standard procedure in preclinical studies. Such delivery provides broader coverage to the central and peripheral nervous system unlike local parenchymal delivery alone. As a clinical application, this approach offers a more reliable method for neurological gene replacement delivery in infants, where skull-mounted devices are not indicated. Here we describe a consistent, precise, and safe method for CSF injection with minimal equipment and technical skills.

Tracheal CT morphology: correlation with distribution and extent of thoracic adipose tissue.

To evaluate the relationship between adipose tissue measurements and anterior bowing of the posterior tracheal wall in a large nonselected group of patients undergoing CT pulmonary angiography (CTPA). Consecutive patients undergoing CTPA over a 4-month period were analyzed retrospectively. Using an adapted scoring system (posterior bowing, flattening, mild/moderate or severe anterior bowing of the posterior tracheal membrane), the axial morphology and cross-sectional area of the trachea at the narrowest point and 1cm above the aortic arch were evaluated. Measurements of adipose tissue were taken (anterior mediastinal fat width, sagittal upper abdominal diameter and subcutaneous fat thickness at the level of the costophrenic angle). Relationships between tracheal morphology and measurements of adipose tissue were analyzed. 296 patients were included (120 males, 176 females, mean age 59years, range 19-90). Severe anterior bowing of the posterior tracheal wall correlated with increasing sagittal upper abdominal diameter (p = 0.002). Mild/moderate and severe anterior bowing of the posterior tracheal wall correlated with increasing mediastinal fat width (p = 0.000 and p = 0.031, respectively). Tracheal cross-sectional area was inversely correlated with increasing subcutaneous fat thickness (p = 0.022). The findings demonstrate a statistically significant relationship between CT tracheal morphology and adipose tissue measurements in a large nonselected population. • There is increasing interest in the effects of obesity on the airways. • A relationship between anterior bowing of the posterior tracheal wall and adipose tissue measurements is demonstrated. • This is of clinical relevance in an increasingly obese population. • Further studies with functional correlation are required.

Comparative evaluation of the tympanic membrane perforations recovery, depending localization

The aim of the study was to evaluate the efficiency tympanic membrane traumatic defect silicone disc shielding in combination with endaural laser therapy depending on the defect location. Materials and methods. The paper analyzes the results of treatment of 50 patients. The first group (25 people) – had a defect in frontal quadrant, the second group (25 people) – in rear forated silicone disk and endaural laser therapy. Each patient received six three-minute radiation sessions. A single biological dose was 50 J/cm2, the total of 300 J/cm2. Results and discussion. Tympanic membrane defect area was evaluated in each group in dynamics. In the first group before the start of treatment, the average perforations area was (14,2 ± 0,93) mm2, and in the second group (18,6 ± 2,31) mm2. After three months of first group observation in 2 (8%) patients tympanic membrane remained defective and the average area was (3,4 ± 071) mm2. The second group the perforation observed in 1 (4%) patient and average area was (2,8 ± 0,63) mm2 area. The differences in groups were considered statistically significant. The average duration of restoration tympanic membrane integrity in first group was (16 ± 5) days, the second group (11 ± 3) days. The differences in groups were considered statistically significant (t = –3,3; p = 0,003). Conclusion. Thus, posterior quadrants tympanic membrane traumatic perforations demonstrated more favorable prognosis in terms of convalescence.

Posterior Mesh Tracheoplasty for Cervical Tracheomalacia: A Novel Trachea-Preserving Technique

Tracheal resection or placement of airway prostheses (stents, tracheostomy tubes, or T tubes) are techniques currently used to treat severe cervical tracheomalacia. We have developed a new technique to secure a polypropylene splint to the posterior membrane of the cervical trachea in a patient with diffuse, acquired tracheobronchomalacia. This novel posterior tracheoplasty avoids anastomotic and intraluminal adverse events that may occur with existing techniques.

A MORPHOLOGICAL STUDY OF PONTICULI OF THE HUMAN ATLAS VERTEBRAE AND ITS CLINICAL SIGNIFICANCE

BACKGROUND: The first cervical vertebra, atlas plays a vital role in the movement of skull & neck. The anatomy of atlas is complex due to its three dimensional structure. There is a groove on superior surface of posterior arch of atlas for passage of 3 rd part of vertebral artery and first cervical spinal nerve (suboccipital nerve). Sometimes the oblique ligament of atlas which is present at the lower border of posterior atlanto-occipital membrane may ossify and convert this groove into a foramen. This foramen may be complete or incomplete, In some cases a bony bridge also extends from lateral masses of atlas to the posterior root of transverse process and form an additional foramen through which vertebral artery travels. The vertebral artery is prone to compression in its entire course between foramen transversarium and foramen magnum during extreme rotation movement of head & neck. This condition may be aggravated by the presence of these ponticuli & results in compromised blood flow and causes vertebrobasilar insufficiency presenting with dizziness, fainting, vertigo, transient diplopia & various neurological disturbances. MATERIALS & METHODS: The present study was carried out on 118 (Male-62, Female-56) dried fully ossified adult human atlas of known sex for the presence of complete or incomplete ring for vertebral artery i.e. different ponticuli on the superior surface of the atlas vertebra. RESULTS: We observed 21.17% cases of ponticulus posterior in which 7.62% specimens had complete ring while 13.55% specimens had incomplete ring & ponticulus lateralis was reported only in 5.93% cases (unilateral: 2.54% & bilateral: 3.39%). Incidence of ponticulus posterior as well as lateralis were more common in male as compared to female. Complete ponticulus posterior was more common in right side, while incomplete ponticulus posterior as well as ponticulus lateralis were more commonly bilaterally. CONCLUSION: As indicated by our study, ponticulus posterior as well as lateralis are not so rare anomaly in the population of Bihar. So, the detail knowledge about these variations is very helpful to the neurophysicians, neurosurgeons, orthopedicians & otolaryngologists who faces regularly the patients complaining about the symptoms of vertebrobasilar insufficiency. These informations are also important for the spine surgeons to prevent vascular complications during spinal surgeries especially in those patients who required screw placements in the lateral mass of atlas.

Investigation of meningomyovertebral structures within the upper cervical epidural space: a sheet plastination study with clinical implications

Background ContextOver the past two decades, soft-tissue structures communicating with the dura mater within the epidural space have become the focus of many anatomical and histopathologic studies. The relationship between these bridging structures has yet to be evaluated in situ. PurposeThis is the first study that used E12 sheet plastination to investigate the epidural space of the upper cervical spine in situ and its associated bridging structures. Given the complexity of this space, this study may prove useful to clinical anatomists and surgeons who operate within this region. Study DesignAnatomical and microscopic analyses of structures that communicate with the dura mater within the upper cervical region were carried out. MethodsGross dissection in conjunction with microscopy was used to evaluate bridging communications of the upper cervical spine in 10 cadavers. To evaluate the in situ arrangement of these structures, E12 sheet plastination was used on 13 cadavers. ResultsIn all 23 specimens, suboccipital fascia coalesced with the dorsal meningovertebral ligament of the atlas, and inserted directly into the posterior surface of the dura as a single but separable laminar layer. At the level of the atlantoaxial interspace, suboccipital fasciae combined and coalesced with the dorsal meningovertebral ligament of the atlas and the axis. These structures inserted into the posterior surface of the dura mater as a single but separable layer. Microscopy validated these findings and E12 sheet plastination revealed the in situ organization of these soft-tissue structures. E12 sheet plastination also provided new information on dural arrangement at the craniocervical junction, which was observed to be composed of periosteum from the occiput but consisted mainly of deep fascia from the rectus capitis posterior minor. ConclusionsE12 sheet plastination has provided in situ visualization of bridging structures within the cervical epidural space and offers new insight into these structures, as well as the composition and arrangement of the posterior atlantooccipital membrane and cerebrospinal dura at the craniocervical junction. This study aims to expand on the anatomical understanding of the upper cervical region while defining structures that may reduce neurosurgical complications, and aid in the understanding of the pathophysiology of certain neurogenic disorders.

A novel respiratory architecture in theSilurian molluscAcaenoplax

AbstractExtant aplacophorans, a group of shell‐less vermiform molluscs, respire through appendages within or projecting from a posterior cavity. Respiratory structures differ between the subclassesCaudofoveata (ctenidia within the cavity) andSolenogastres (folds of the mantle itself).Acaenoplax hayae, aSilurian vermiform mollusc from theHerefordshireLagerstätte,England, exhibits characteristics of both these groups. While recent work places it within the crown groupAplacophora, near the caudofoveates, initial observations suggested that its respiratory structures were closer to those of the solenogastres. Here, we present new reconstructions of the posterior ofAcaenoplaxprepared with the aim of resolving features obscured when prior studies were undertaken. These reconstructions detail a novel posterior architecture, not closely comparable to that of either extant aplacophoran group, in which respiratory projections arise from a membrane that partly encloses a central posterior cavity. The posterior membrane is flanked by small spherical projections; both membrane and spherical projections are apparently unique within theAplacophora. The existence of this previously undocumented respiratory system underlines the diversity of the aplacophoran clade during thePalaeozoic.

Minimally invasive approach for small ventrally located intradural lesions of the craniovertebral junction.

The surgical management of lesions ventral to the neuraxis at the level of the craniovertebral junction (CVJ) and upper cervical spine is challenging. Here, the authors describe a minimally invasive dorsal approach for small ventrally located intradural lesions at the CVJ as an alternative for the more extensive classic transoral approach or variants of suboccipital approaches. Between 2012 and 2014, 6 symptomatic patients with a small lesion of the ventral aspect at the CVJ level were treated using a minimally invasive dorsal approach at the University Medical Center in Hamburg-Eppendorf, Germany. The anatomical distance between the posterior atlantooccipital membrane and the posterior atlantoaxial ligament, as determined by CT images, was assessed in the treated patients and in 100 untreated persons. The authors treated 6 patients (mean age 54.7 years) who had a clinical presentation of mild neurological symptoms that disappeared after resection. Minimally invasive surgical dorsal access was achieved by using tubular systems and using the natural space between the occiput (C-0) and C-1, and in 1 case between C-1 and C-2, without having to remove bony structures. The postoperative course in each of the 6 patients was uneventful. The neuropatho-logical findings confirmed a meningotheliomatous meningioma (WHO Grade I) in 5 cases and an extramedullary cavernous hemangioma in 1 case. MRI confirmed complete resection of all the lesions. The atlantooccipital distances ranged from 3 to 17 mm (mean 8.98 mm) in the supine neutral position, and the atlantoaxial distances ranged from 5 to 17 mm (mean 10.56 mm). There were no significant differences between women and men (atlantooccipital p = 0.14; atlantoaxial p = 0.72). The results of this study demonstrate that the minimally invasive dorsal approach using the space between C-0 and C-1 or C-1 and C-2 provides direct and sufficient exposure for the safe surgical resection of small ventrally located intradural lesions at the CVJ level while reducing the necessity for musculoskeletal preparation to a minimum.

Direct tracheobronchopexy to correct airway collapse due to severe tracheobronchomalacia: Short-term outcomes in a series of 20 patients

PurposeTracheobronchomalacia (TBM) is associated with esophageal atresia, tracheoesophageal fistulas, and congenital heart disease. TBM results in chronic cough, poor mucous clearance, and recurrent pneumonias. Apparent life-threatening events or recurrent pneumonias may require surgery. TBM is commonly treated with an aortopexy, which indirectly elevates trachea’s anterior wall. However, malformed tracheal cartilage and posterior tracheal membrane intrusion may limit its effectiveness. This study describes patient outcomes undergoing direct tracheobronchopexy for TBM. MethodsThe records of patients that underwent direct tracheobronchopexy at our institution from January 2011 to April 2014 were retrospectively reviewed. Primary outcomes included TBM recurrence and resolution of the primary symptoms. Data were analyzed by McNemar’s test for matched binary pairs and logistic regression modeling to account for the endoscopic presence of luminal narrowing over multiple time points per patient. ResultsTwenty patients were identified. Preoperative evaluation guided the type of tracheobronchopexy. 30% had isolated anterior and 50% isolated posterior tracheobronchopexies, while 20% had both. Follow-up was 5months (range, 0.5–38). No patients had postoperative ALTEs, and pneumonias were significantly decreased (p=0.0005). Fewer patients had tracheobronchial collapse at postoperative endoscopic exam in these anatomical regions: middle trachea (p=0.01), lower trachea (p<0.001), and right bronchus (p=0.04). ConclusionThe use of direct tracheobronchopexy resulted in ALTE resolution and reduction of recurrent pneumonias in our patients. TBM was also reduced in the middle and lower trachea and right mainstem bronchus. Given the heterogeneity of our population, further studies are needed to ascertain longer-term outcomes and a grading scale for TBM severity.

Congenital obstructive posterior urethral membranes and recurrent urinary tract infection: a rare case of congenital hypertrophy of the verumontanum

Congenital obstructive posterior urethral membranes (COPUM) is a complex disease closely related to several pathological changes in kidney development and function, as a result of urinary reflux since in utero. This congenital anomaly of urinary tract potentially causes hydroureteronephrosis that is often associated with recurrent urinary tract infections and, ultimately, one of the most common causes of end-stage renal disease in children.1,2 Congenital hypertrophy of the verumontanum as part of COPUM is very rare. Only a few reports have been written on congenital hypertrophy of the vermontanum causing congenital obstructive uropathy.3-6

Posterior hyaloid findings as visualized by SD OCT

AbstractPurpose To direct attention to the structures of the posterior hyaloid as visualized by SD OCT, and to improve understanding of vitreo‐retinal biomechanics.Methods Findings were collected from a Wetzlar study cohort of subjects who gave their informed consent to gather experience in vitreal SD OCT. In addition, OCT images were worked up retrospectively from the Mannheim pool of recordings. Exams were performed by the RS 3000 SD OCT (Nidek) or by the Spectralis SD OCT (Heidelberg engineering). Images underwent a modified processing to favour the visualization of vitreous structures.Results Observations range from a completely attached and homogeneous hyaloid with regular foveal profile at the age of 75, to premacular vitreal bursae and intravitreal lacunae, regions of low and high density within an apparently disintegrating hyaloid, intravitreal condensates and supposed cell aggregations. Various patterns of holes within the posterior limitating vitreal membrane appeared in connection with vitreo‐retinal and vitreo‐papillar traction of a partially detached vitreousConclusion OCT visualization of vitreous structures contributes to our understanding of vitreal degradation and vitreo ‐ retinal interaction. Commercial interest