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Purpose To describe a trypan blue dye staining technique under air, a modification of the previously described 30 G needle under-air technique. Design This is a prospective, randomized study of 1,000 eyes of 952 patients undergoing phacoemulsification in a private practice setting from January 2015 to August 2016. Three variants as a modification of the previously known 30 G needle technique are described. In our technique, after injecting one drop of the dye under air, the needle is kept in the anterior chamber (AC) for 15 seconds. In the second variation, along with the additional hold time, 0.05 mL air is injected prior to dye injection to deepen the AC in eyes with shallow ACs or in cases with increased posterior pressure. The third variation is the selective painting approach in which more than one drop is injected for a homogenous staining. Main outcome measures The main outcome measures were safety and reproducibility of the technique along with homogeneity and uniformity of the anterior capsule staining. Results AC remained stable during the hold time of 15 seconds with no egress of air. No iatrogenic trauma occurred in any of the cases. All cases had a homogeneously stained anterior capsule. The staining intensity was excellent in 80.8% of the eyes and good in 19.2% of the eyes. Conclusion This is a safe, simple, and cost-effective technique which achieves consistent, uniform, and reproducible staining. It overcomes the shortcomings of the known 30 G needle technique., Video abstract

PURPOSE To describe two cases of suprachoroidal hemorrhage during Descemet membrane endothelial keratoplasty (DMEK). METHODS Two patients with pseudophakic bullous keratopathy (PBK) underwent DMEK and proceeded to develop intraoperative suprachoroidal hemorrhage. Reports of both cases are documented, including potential risk factors, intraoperative events, and postoperative outcomes and interventions. RESULTS Both cases required premature abortion of the operation following the abrupt onset of significant posterior pressure indicating potential suprachoroidal hemorrhage. Postoperative visual acuity measured light perception or worse, and both patients declined further intervention. CONCLUSIONS Suprachoroidal hemorrhage is a rare but potentially devastating intraoperative complication which may occur during DMEK, particularly in eyes with relevant risk factors. An inability to deepen the anterior chamber following graft implantation may signify the condition.

In the past, pediatric corneal opacities have been grouped into congenital and acquired causes. We discuss corneal opacities and group them based on the treatment, including penetrating keratoplasty, endothelial keratoplasty, and optical iridectomy. Modern surgery for pediatric corneal opacities is following the trend in adult corneal surgery, namely, to replace only the diseased corneal layers. Little definitive surgical advice can be easily gleaned from prior publications on pediatric penetrating keratoplasty, due to the inclusion of diverse patients, techniques, and surgical timing. Visual development, or the lack of it – deprivation amblyopia – is an ever-present issue for the pediatric corneal surgeon, in contrast to the surgical considerations of adult corneal opacity. Each of the three above modalities has its distinct pros and cons in children. For example, while pediatric endothelial keratoplasty requires fewer examinations under anesthesia for suture removal, fewer suture-related complications, and less induced astigmatism compared with penetrating keratoplasty, surgery in children must be altered from the adult technique due to the child’s shallower anterior chamber and relative positive posterior pressure. Optical iridectomy should be considered when the central opacity is associated with at least several millimeters of clear peripheral cornea. The treatment of pediatric corneal opacities, while challenging, can bring tremendous rewards, especially when the relatively recent techniques of selective corneal replacement may be applied. This chapter discusses surgical treatment options for pediatric corneal opacities, including penetrating, endothelial, and lamellar keratoplasties. Attention will also be given to the use of Boston keratoprostheses as well as a less frequent, but highly valuable, optical iridectomy. The management of coincident glaucoma will also be discussed.

Objective: to investigate the correlation between the tongue pressure and the electrical activity of the suprahyoid muscles. Methods: a across-sectional, observational and analytical study conducted with 15 men and 22 women. Each participant underwent simultaneous assessment of maximal tongue pressure through the Iowa Oral Performance Instrument (IOPI) and the surface electromyography of the suprahyoid muscles. They were asked to press the tongue against the hard palate in the anterior and posterior region, with and without IOPI. The adopted significance level of the performed analyses was 5%. Results: there was a moderate and significant correlation only between suprahyoid electrical activity and tongue pressure in the posterior region. It was verified that the measured electrical potentials, when using the IOPI, were greater in the tasks of anterior pressure than in the tasks of the posterior one, bilaterally. Without using the IOPI, the electrical potentials were greater in the posterior pressure than in the anterior one, bilaterally. Finally, the values of lingual pressure were compared with the bulb positioned in the anterior and posterior parts, and the anterior tongue pressure was higher. Conclusion: there was a moderate correlation between tongue pressure and electrical potential of the suprahyoid muscles, researched by the surface electromyography, only when performing activities with the posterior portion of the tongue.

[Purpose] In the present study, we aimed to determine the effects of backpack position on foot weight distribution of standing school-aged children. [Subjects] Thirty school-aged children volunteered to participate in this study. [Methods] The subjects randomly performed four types of carrying a backpack: no backpack (condition-1), carrying a backpack at C7 (condition-2), carrying a backpack at 10 cm below C7 (condition-3), and carrying a backpack at 20 cm below C7 (condition-4). [Results] Statistically significant differences were noted in the anterior and posterior pressure values, and in the anterior-to-posterior ratio, among the four conditions (p < 0.05). Post-hoc analysis indicated that the pressure value of condition-4 was significantly lower in the anterior foot region and higher in the posterior foot region than in condition-2 and condition-3. In addition, the anterior-to-posterior ratio was lower in condition-4 than in condition-2 and condition-3. [Conclusion] These findings suggest that carrying a backpack in a higher position, with fastening of the shoulder strap, may be more favorable for normalizing the foot weight distribution.

PURPOSE: To determine the biomechanical response of the rabbit cornea to inflation under posterior and anterior pressure. METHODS: Twelve Japanese white rabbits were included in the study. A randomly selected eye from each animal was subjected to posterior pressure in an inflation test rig, and the other eye was subjected to anterior pressure after manually reversing its curvature. Specimens were loaded by cycles of pressure up to 40 mmHg, and the experimentally obtained pressure-deformation data were used to derive the stress–strain behavior of each eye using an inverse modeling procedure. RESULTS: The differences between the two groups in corneal thickness, diameter, and intraocular pressure (IOP) were not statistically significant ( P =.935, .879 and .368, respectively). Corneas tested under posterior pressure displayed significantly higher stiffness (as measured by the tangent modulus) than those inflated by anterior pressure ( P< .001). CONCLUSIONS: Cornea is a nonlinear viscoelastic tissue that presents different mechanical properties when tested under posterior and anterior pressure. The determination of the behavior under both forms of pressure could contribute to the construction of accurate finite element simulations of corneal behavior and the correction of tonometric IOP measurements. The difference in mechanical behavior between anteriorly and posteriorly loaded corneas in the study, although significant, could have been partly affected by the changes in microstructure possibly caused by changing corneal form to enable anterior loading.

Backgroud To evaluate the symmetry of corneal biomechanical metrics, measured using an ocular response analyzer (ORA) and self-built corneal inflation test platform, in bilateral rabbit corneas and to investigate their relationship with physical intraocular pressure (IOPp). Methods Twenty fresh enucleated eyes from ten rabbits were used for ex vivo whole ocular globe inflation. IOP was increased from 7.5 to 37.5 mmHg with 7.5 mmHg steps and biomechanical metrics were acquired using the ORA. At least 3 examinations were performed at each pressure stage. Two biomechanical metrics, corneal hysteresis (CH) and corneal resistance factor (CRF) were recorded and analyzed as a function of IOPp. Corneal specimens were then excised from the intact ocular globe and tested under inflation conditions up to 45.7 mmHg posterior pressure. The experimental pressure-deformation data was analyzed using an inverse modeling procedure to derive the stress-strain behavior of the cornea. Results A comparison of corneal shape parameters showed no statistically significant difference (P > 0.05) between bilateral eyes. Similarly, there were no statistically significant differences in values of CH, CRF and corneal stiffness (as measured by the tangent modulus, Et) between bilateral eyes (CH: F = 0.94, P = 0.54; CRF: F = 4.42, P = 0.35; Et: F = 3.15, P = 0.12) at different pressure levels. IOPp was highly correlated with CRF while the relationship with CH was less pronounced. Conclusions An obvious interocular symmetry in biomechanical metrics is found in this research. IOP has been shown to have important influences on the value of CRF provided by ORA.

Purpose. To explore the probability and variation in biomechanical measurements of rabbit cornea by a modified Scheimpflug device.Methods. A modified Scheimpflug device was developed by imaging anterior segment of the model imitating the intact eye at various posterior pressures. The eight isolated rabbit corneas were mounted on the Barron artificial chamber and images of the anterior segment were taken at posterior pressures of 15, 30, 45, 60, and 75 mmHg by the device. The repeatability and reliability of the parameters including CCT, ACD, ACV, and CV were evaluated at each posterior pressure. All the variations of the parameters at the different posterior pressures were calculated.Results. All parameters showed good intraobserver reliability (Cronbach’s alpha; intraclass correlation coefficient,α, ICC > 0.96) and repeatability in the modified Scheimpflug device. With the increase of posterior pressures, the ratio of CCT decreased linearly and the bulk modulus gradually reduced to a platform. The increase of ACD was almost linear with the posterior pressures elevated.Conclusions. The modified Scheimpflug device was a valuable tool to investigate the biomechanics of the cornea. The posterior pressure 15–75 mmHg range produced small viscoelastic deformations and nearly linear pressure-deformation response in the rabbit cornea.

Pressure sores present a challenge to people with rectal and cervical cancers due to weight loss, compromised nutrition, chemotherapy and radiotherapy. Affected individuals often experience intense pain on sitting, and prefer to spend the majority of their time lying down. This pilot study, employing a case study design, investigated the pressure care needs of such persons using pressure mapping, a technology designed to measure pressures at the seating interface. Four participants were mapped on a selection of five cushions, three of which were developed to specifically reduce midline posterior pressure/pain relief. Participants rated the cushions for comfort. Findings demonstrated an inconsistent relationship between interface pressures and perceived cushion comfort, suggesting that patient-rated comfort is a poor indicator of high interface pressures. The specialized cushions did not always meet the needs of this target population and no one cushion suited all. This study demonstrated the precarious clinical balance needed between comfort and achieving optimal pressure reduction in cushion prescription for this client group, and suggested that comfort was more important than pressure reduction in terms of their seating needs.

At the oral stage of swallowing, the tongue plays a major role and proper tongue performance is necessary to form the bolus and transfer it to the pharynx. For the present study we built a prototype device for safe and handy objective estimation of tongue motion and coordination with laryngeal elevation at swallowing. The device records tongue pressure by means of two strain gauge pressure transducers aligned 20 mm apart on a brass strap placed along the palatal midline. Laryngeal vibration is recorded with piezo-electric acceleration transducers. Time differences between pressure onset at the anterior and posterior transducers and the first spike from laryngeal vibration are measured. Ten healthy subjects were asked five times to swallow 5 mL of water. Pressure onset at the anterior transducer preceded posterior pressure by 294 +/- 164 ms. Given the distance between the transducers, the tongue contracted (squeezed) at a speed of 93 +/- 60 mm s(-1). Laryngeal vibration occurred 671 +/- 175 ms after the onset of anterior pressure. There was considerable variation in these parameters between subjects. Though the data is limited, the device successfully and easily revealed certain aspects of tongue motion and coordination with laryngeal elevation.

PURPOSE The aim of this study was to determine a noninvasive method of evaluating external iliac endofibrosis in cyclists. METHODS Eighteen highly trained male cyclists were divided into two groups: a pathology group (PG; 3 professional and 4 elite) and a control group (CG; 6 professional and 5 elite). Mean age was 26 +/- 6.1 yr for the PG and 24 +/- 4.09 for the CG. We studied humeral and tibial posterior pressure by using Doppler ultrasound and the ankle to arm index (AAI) before and after an incremental exercise test, performed on bike-ergometer until exhaustion. A Wilcoxon test was used to compare pressures and AAI in the PG. A Mann-Whitney test was used to compare the PG with the CG. Fisher discriminant analysis was done to obtain a classification of the legs in ill or normal legs. RESULTS The minimal AAI achieved in the PG was 0.76 +/- 0.13 for the normal leg (NL) and 0.35 +/- 0.04 for the ill leg (IL). We found significant differences (P < 0.01) from the 1st to 4th minute after exercise between the NL and the IL in the PG, and from the 1st to 10th minute after exercise between the IL and CG. We found significant differences in leg pressures between NL and IL in PG from the 1st to 4th minute (P < 0.01), and from the 1st to the 10th minute after exercise between CG and IL in the PG. Through discriminant analysis, we obtained a classification of the legs as ill or normal by applying a mathematical function at each recovery time studied. CONCLUSIONS AAI and leg pressures response to maximal exercise is a valid and noninvasive method for the evaluation of external iliac endofibrosis.

We experienced two cases of the influx of the sclerotomy site bleeding into the anterior chamber during 23-gauge sutureless vitrectomy for pseudophakic rhegmatogenous retinal detachment. Soon after the removal of a 23-gauge microcannula at the end of the surgery, presumed sclerotomy site hemorrhage was rapidly fluxed into the anterior chamber. The anterior chamber bleeding might come from the sclerotomies rather than from episcleral vessels. The posterior pressure in the gas-filled pseudophakic eye might have pushed the sclerotomy site bleeding into the anterior chamber. We could not find any vitreous hemorrhages. The hemorrhage within the anterior chamber spontaneously absorbed within 14 days.

PURPOSE The purpose of the study was to evaluate the in vitro accuracy of correction factors in decreasing the error in the intraocular pressure (IOP) measurements obtained using the Goldmann Applanation Tonometer (GAT). METHODS Nineteen donor corneas, from individuals aged between 57 and 99 years (mean 75.7 years, standard deviation±11.4 years) were subjected to posterior pressure simulating in vivo true IOP (IOPT) using an inflation test rig. Central corneal thickness and corneal curvature were measured. The posterior pressure was set at 25 different pressure levels between 5 and 45 mm Hg and IOP was measured using the GAT. Five different correction equations were applied to the IOP measurements obtained using the GAT to determine corrected IOP. The multiparameter correction equations applied were derived by Elsheikh, Ehlers, Chihara, Shimmyo et al, and Orssengo and Pye. The differences between IOPT and the IOP measured using the GAT were recorded as uncorrected errors, whereas the differences between IOPT and each of the corrected IOP were the tonometry errors after correction. RESULTS The mean and standard deviation of error in tonometry before correction was +2.25±0.62 mm Hg. The mean errors in tonometry after correction using the Elsheikh and Chihara equations were +0.78±0.62 and +1.08±0.61 mm Hg, respectively. The mean errors in tonometry for the Ehlers, Shimmyo et al, and Orssengo and Pye equations were negative, indicating an overcorrection; the values were -0.75±2.28, -1.27±1.85, and -0.77±1.83 mm Hg, respectively. CONCLUSIONS The Elsheikh and the Chihara et al's equations considerably decreased error in IOP measurements obtained by the GAT when compared with IOPT and were more consistent than other correction equations. The 2 equations may be of clinical utility in obtaining estimates of IOPT.

A modified suture technique for precise knot placement in the Hoffman corneoscleral pocket technique of scleral fixation is described. Both loops of the polypropylene suture passing from the intraocular device through the sclera and conjunctiva are retrieved from the pocket. A loop of suture is pulled through 3 suture throws made using the second suture loop, forming a half bow. Centration of the intraocular lens (IOL)–capsular bag is checked. If the suture tension is too tight, the surgeon can easily undo the knot of the half-bow knot by pulling it free and can then retie the sliding knot. When the IOL–capsular bag is centered, the suture loop is cut and the free end removed. The second suture end is retrieved from the pocket, and knot tying is completed without further adjustment to the tension. Posterior pressure on the intraocular device centers it and settles the knot within the sclera at the fixation point. Financial Disclosure The author has no financial or proprietary interest in any material or method mentioned.

An experimental study has been conducted to determine the stress–strain behaviour of human corneal tissue and how the behaviour varies with age. Fifty-seven well-preserved ex vivo donor corneas aged between 30 and 99 years were subjected to cycles of posterior pressure up to 60 mm Hg while monitoring their behaviour. The corneas were mechanically clamped along their ring of scleral tissue and kept in physiological conditions of temperature and hydration. The tissue demonstrated hyper-elastic pressure-deformation and stress–strain behaviour that closely matched an exponential trend. Clear stiffening (increased resistance to deformation) with age was observed in all loading cycles, and the rate of stiffness growth was nonlinear with bias towards older specimens. With a strong statistical association between stiffness and age ( p < 0.05), it was possible to develop generic stress–strain equations that were suitable for all ages between 30 and 99 years. These equations, which closely matched the experimental results, depicted corneal stiffening with age in a form suitable for implementation in numerical simulations of ocular biomechanical behaviour.

We describe a technique to position patients with severe kyphosis so the head is horizontal. The legs are lifted into the Trendelenburg position, and the patient is supported with straps similar to those of a parachute. Although the patient's legs are high above the head and jugular distension has been observed, we have not noticed posterior pressure in the 2 cases we describe. This technique is similar to that described by others but has the additional security of the parachute-like straps.

Examination of victims exposed to strangulation is well known in clinical forensic medicine. Not all cases show the objective signs to be found at the examination, e.g. petechial haemorrhages in the eyes and face as well as bruises and abrasions on the neck. In cases without objective signs especially, examination of the laryngeal crepitus might be an aid to diagnosis in strangulation. Laryngeal crepitus is felt by the examiner when the larynx is moved from side to side with a slight posterior pressure. When absent, it is a clinical sign of a mass in the retrolaryngeal space or hypopharynx, probably due to a laryngeal trauma. This paper describes three cases of strangulation where the clinical examinations showed a temporary absence of laryngeal crepitus.

The precision (reproducibility) of active and passive recordings of the retruded position of the mandible was studied by two examiners on 10 patients with mandibular dysfunction symptoms. The position of the mandible was recorded with an intra-oral graphic method, before and after treatment of the symptoms. The precision of the recording was highest when the retruded position was recorded by passive hinge movement and lowest when it was recorded by active hinge movement and when recording habitual closure. Both systematical and accidental errors tended to be somewhat larger among these patients than that previously found among individuals without signs or symptoms of mandibular dysfunction. The accidental errors in antero-posterior and medio-lateral directions were the same fo both examiners and of the same magnitude before and after treatment of the symptoms. Both examiners recorded the retruded position on the average 0.20 mm more posterior after treatment than before. The results showed that because of its good reproducibility the retruded position of the mandible can be recommended as a reference position in functional analysis of occlusion and for jaw recordings also in patients with TMJ muscle-pain dysfunction symptoms. During the recording the conventional technique with passive hinge movement and a posterior pressure should be used.

The pressure profile of the upper esophageal sphincter was characterized in nine normal subjects. Directionally oriented intraluminal pressures were recorded, at 0.5-cm intervals over a 6-cm segment that encompassed the sphincter, by a high-fidelity low-compliance recording system. The peak resting pressure was directed posteriorly, and the lowest pressures were recorded from the lateral orientations. Significant axial asymmetry was observed with peak posterior pressure 0.55 cm more distal than the anterior pressure. Calculations of variability of pressures recorded at each interval showed the peak pressure to be the most reproducible measurement for each subject. Isotonic saline and acid infusions into the esophagus distal to the sphincter resulted in increased sphincteric peak resting pressure (acid greater than saline). There was axial lengthening of the sphincteric pressure zone with infusion of acid and saline, but this observed increase in length was not significant except at the 50 mmHg level. Pressure profiles recorded during 0.5-cm station pull-throughs were virtually identical to those obtained by a rapid continuous pull-through technique.

We report our initial studies with a new organic tissue glue (Tisseel) in the closure of cataract incisions made in fresh cadaver eyes. We made two types of cataract incisions, posterior beveled and scleral pocket, and closed them with nylon sutures, glue, or a combination of both. The 11-mm posterior-beveled incision required eight nylon sutures, with or without glue, to maintain wound integrity at high intraocular pressures. We found the 7-mm and 11-mm pocket-type incisions to be essentially self-sealing and to leak only when posterior scleral lip pressure was applied. Once glue was added, even high posterior pressure did not disrupt the wound. This glue may thus present an alternative to suture closure of scleral pocket cataract incisions.

The effect of calcaneal traction on the compartmental pressure in the legs of five individuals with tibial fractures was studied. Mean resting pressures without traction were found to be 31.9 mmHg for the deep posterior compartment and 27.0 mmHg for the anterior compartment. For each kilogram weight of traction applied the deep posterior pressure rose by 5.7 per cent of the resting value and the anterior pressure by 1.6 per cent. It is suggested that the weight of traction should be only sufficient to render the patient comfortable and maintain alignment of the limb. Excessive traction is likely to increase the risk of compartmental ischaemia. The application of six kilograms of traction would raise the mean resting pressure by 34 per cent from 31.9 to 42.7 mmHg.

We tested a manometric assembly employing a sleeve sensor that is able to monitor anterior or posterior pressure in the human upper esophageal sphincter (UES) for prolonged intervals. When compared to rapid pull-through measurement of UES pressure obtained with conventional manometric assemblies, the sleeve sensor measured significantly lower UES pressures with less variability between subjects, thereby suggesting that the rapid pull-through maneuver stimulates the UES to contract. Concurrent recordings of UES pressure with a sleeve sensor and a side-hole sensor during a slow station pull-through yielded almost equal pressure values at the peak of the high-pressure zone (station zero), but the side-hole site recorded significantly lower pressures than the sleeve at stations 0.5 cm or more from the peak of the high-pressure zone. During 10 min of recording at station zero, the sleeve sensor recorded greater pressures than the side-hole sensor. This finding demonstrated the suceptibility of the side-hole sensor to axial movement relative to peak UES pressure. When stationary, both the sleeve sensor and the side-hole sensor recorded significantly lower UES pressure after 1–2 min of recording, again suggesting that movement of the recording assembly stimulates the UES to contract. Sleeve recordings of swallow-induced UES relaxations showed that UES relaxations induced by water swallows were slightly longer than those induced by dry swallows. Augmentations of UES pressure induced by balloon distension of the esophageal body were also recorded. We conclude that the sleeve sensor is a suitable method for investigating the normal physiology and pathophysiology of the UES in human subjects.

anot uncommoncomplication ofimperforate vagina in thenewborn. We donotpropose todiscuss the relatively commonproblem ofvaginal occlusion duetolabial adhesions (Fig. 1),whichcanbe easily separated withlittle ornobleeding. Hydrocolpos inthenewborn femaledueto imperforate hymenortoocclusion byamembrane inthelowerthird ofthevagina isnotexcessively rare.Atorshortly after birth theinfant presents withlower abdominal swelling andabulging membraneisseenatthevaginal orifice (Fig. 2).This bulging membrane looks like acystocele andwhen gently reduced theurethral orifice canbeseen anteriorly. Occasionally theremay be a tiny opening intheoccluding membrane through which a whitemucoidmaterial canbeextruded. The anomaly hasbeenfully described byMahoney andChamberlain (1940), byGross(1953), byCaffey (1956), andbymanyothers andforthepurposes ofthepresent communication a brief description oftheir findings will besufficient. Inthis condition thevagina isinvariably greatly distended-hydrocolpos-and onoccasions theaccumulated fluid canstretch thecervical canal andthe bodyoftheuterus aswell-hydrometrocolposthough wehaveseentheuterine cavity distended onlyononeoccasion. Theballooned genital tract arises fromthepelvic floor intotheabdominal cavity. Thecyst isfilled withclear ormucoid fluid whichtendstobecomepurulent frombacterial invasion, giving risetopyocolpos. Theuterine tubes havenotbeeninvolved inanyofthereported cases. The distended genital tractmay cause urinary obstruction andtheenlargement ofthe bladder mayhinder palpation ofthevaginal cyst. Megaloureter andhydronephrosis mayfollow and pyuria willbea further complication. Posterior pressure maycause rectal obstruction. Theremay * A paperreadatameeting oftheBritish Association ofPaediatric Surgeons heldinLondoninJuly1960. berespiratory embarrassment through theupward displacement of theabdominal contents. On digital rectal examination thepelvis isfilled bya massprojecting against thehollow ofthesacrum. On inspection ofthevagina abulging membrane isseenatorabovethehymen.Insuchpatients a needle isinserted through themembraneandfluid isaspirated toconfirm thediagnosis. Radioopaquefluidmay be instilled to outline the obstructed vagina(Fig.3).Havingmadethe diagnosis theoccluding membraneisslit witha knife andthecystcontents areevacuated. Lesscommonly thehydrocolpos isduetoatresia ofthelower vagina (White andDennison, 1958) and

To the Editor:— Mouth-to-mouth resuscitation is the preferred method of assisting ventilation in the emergency situation and is being taught to many lay groups such as lifeguards and firemen. However, there are complications attendant with the use of the technique, particularly by the less experienced. Complications include partial or total airway obstruction resulting in air being vented via the esophagus into the stomach when the operator exhales forcibly, and active or passive regurgitation of the victim's stomach contents into the upper airway. Since the report of Sellick, 1 many anesthesiologists have used posterior displacement of the cricoid cartilage to prevent active or passive regurgitation during the induction of anesthesia prior to insertion of an endotracheal tube in the patient with a full stomach. The cricoid cartilage is signet-ring shaped with the large flat plate just anterior to the esophagus. By applying posterior pressure to the skin over the anterior surface

• Positive vitreous pressure during penetrating keratoplasty can be difficult to manage. Despite preventive measures, positive vitreous pressure may occur and appropriate intervention is necessary to prevent serious complications. We describe a technique that may be used intraoperatively to restore a formed anterior segment and to prevent vitreous loss when persistent positive vitreous pressure occurs, while attempting to implant a pseudophakos. A 27-gauge needle, passed across the anterior chamber from limbus to limbus, just anterior to the iris, will stabilize the pseudophakos, restore the anterior chamber depth, and allow donor-tissue suturing.