Brain spatula with transparent tip: technical note

A newly developed brain spatula with transparent tip for brain retraction is introduced. The high-molecular polymer plastic material is used only for the tip of the new spatula whilst rest of the spatula is made up of the ordinary malleable metal. The transparent nature of the spatula tip helps us in observing the retracted brain vessels and cranial nerves in continuity with the main operating area. The extent of distortion as a result of the retraction can be directly observed assisting in prevention of an inadvertent injury. The new brain spatula with transparent tip is helpful for microneurosurgery under high magnification. Various shapes and sizes of the spatula can be used.     

Phacoemulsification of a nucleus in the vitreous cavity

Loss of the crystalline lens into the vitreous cavity can lead to corneal damage and expulsive hemorrhage. In this technique, the lens is released from adhesions by vitrectomy and then extracted from the vitreous cavity by phacoemulsification using a special tip. No protective liquids are used to cover the retina. This technique was successful in 44 patients.     

Phacoemulsification and silicone oil removal through a single corneal incision

OBJECTIVE: Cataracts are a frequent complication after silicone oil infusion for the repair of complicated retinal detachments, occurring in up to 100% of eyes retaining silicone oil for 6 months or more. The authors devised a combined procedure for cataract and silicone oil removal with intraocular lens (IOL) implantation through a single corneal incision and evaluated their results. DESIGN: A prospective, noncomparative case series. PARTICIPANTS: Thirty-four eyes of 34 consecutive patients with a history of retinal detachment repair requiring silicone oil placement in whom a clinically significant cataract subsequently developed were identified when removal of silicone oil was scheduled. INTERVENTION: All 34 eyes were prospectively entered into a study to evaluate the efficacy and potential complications of a combined procedure for cataract and silicone oil removal with posterior chamber lens implantation. All patients underwent uncomplicated phacoemulsification removal of cataract followed by removal of silicone oil and placement of an IOL through a single corneal incision. MAIN OUTCOME MEASURE: Recurrent retinal detachment and IOL-related complications were measured. RESULTS: Ten eyes had recurrent retinal detachments develop. Final visual acuity ranged from 6/12 to hand movements with 25 eyes (74%) showing stabilized or improved vision. Pre-existing macular pathology and recurrent retinal detachment generally were responsible for poor visual outcome. CONCLUSIONS: Combined phacoemulsification, IOL implant with silicone oil removal is a useful procedure in these complicated eyes. Visual outcome generally is good with improvement in visual acuity, even with recurrent retinal detachment or pre-existing macular pathology or both.     

Glottic positioning of the endotracheal tube tip: a diagnostic dilemma

Distal placement of the endotracheal tube tip in the glottic opening is rarely discussed in most emergency medicine, surgery, and prehospital medicine texts. We report three cases of glottic intubation recognized after the patients were thought to have been successfully intubated. Glottic positioning of the endotracheal tube tip went unrecognized initially because of the absence of air heard over the epigastrium, the presence of bilateral breath sounds, and acceptable readings by both pulse oximetry and capnography. Recognition of this complication is aided by the use of radiographic findings, inappropriate endotracheal tube depth, and the presence of inadequate ventilatory volumes. Potential complications of glottic intubation include dislodgement of the endotracheal tube, kinking of the tube, and inadequate protection of the airway.     

Metastatic squamous cell carcinoma of the nasal tip: a case report

PURPOSE: Valproate (VPA) has been linked to coagulation disturbances, with both impaired and exaggerated clotting, which has been attributed to an effect of VPA on platelets or hemostatic proteins. Additional thrombocytic function testing may help to identify patients at risk of increased bleeding caused by platelet dysfunction. METHODS: We evaluated the influence of VPA on hematologic routine values and platelet activation by using immunostaining and flow cytometry in 30 patients receiving long-term VPA therapy and in 30 controls. RESULTS: The fraction of activated platelets was similar in both groups; however, the general extent of platelet activation was significantly lower in the patient group, with considerable interindividual variability. In addition, patients had a significantly lower platelet count, prolonged thrombin time, and higher mean corpuscular hemoglobin. CONCLUSIONS: Our data confirm the previously reported hematologic changes caused by VPA and additionally suggest that VPA impairs procoagulatory thrombocytic function, which is reflected by reduced platelet activation and increased thrombin time. Possible mechanisms of VPA-platelet interaction are discussed.     

Phacoemulsification and lens implantation in patients treated with aspirin or warfarin

PURPOSE: To determine the incidence and nature of hemorrhagic complications in patients having phacoemulsification and foldable intraocular lens (IOL) implantation while taking aspirin or warfarin. SETTING: The Jules Stein Eye Institute, University of California at Los Angeles School of Medicine, Los Angeles, California, USA. METHODS: This retrospective study reviewed the charts from the practice of 1 ophthalmic surgeon. The type of medication, dosage, indication for anticoagulant therapy, type of incision, type of anesthesia, and intraoperative and postoperative hemorrhagic complications were recorded. RESULTS: Sixty-two patients (82 eyes) taking aspirin and 25 patients (31 eyes) taking warfarin were identified. Seven eyes in the aspirin group (8.5%) and 3 in the warfarin group (9.7%) experienced subconjunctival hemorrhages. Eight of the 10 subconjunctival hemorrhages occurred in eyes with scleral incisions. The remaining 2 occurred in eyes with corneal incisions. No eye developed lid ecchymosis, retrobulbar hemorrhage, hyphema, or suprachoroidal hemorrhage. CONCLUSIONS: Phacoemulsification with foldable IOL implantation was performed safely in patients taking aspirin or warfarin. Subconjunctival hemorrhage was the most common hemorrhagic complication.     

Changes in nasal tip projection and rotation after septorhinoplasty: a cephalometric analysis

PURPOSE: This prospective study reports on changes in nasal tip projection and nasal tip rotation before and after septorhinoplasty analyzed cephalometrically. PATIENTS AND METHODS: Forty patients undergoing primary septorhinoplasty were studied prospectively. Lateral cephalometric radiographs taken in the natural head position were obtained before and 6 to 45 months (mean, 17.1) after surgery. In 10 patients, serial radiographs were taken at 6 and 12 months, and in seven patients they were taken at 12 and 24 months after surgery. Nasal tip projection (NTP) was defined as the distance between articulare (Ar) and pronasion (PRN). Nasal tip rotation (NTR) was defined as the change in the angle (N-Ar-PRN) after surgery. A surgical goal to increase, decrease, or maintain NTP and NTR was assigned to each patient before surgery. RESULTS: NTP changed in the desired direction in 16 of 40 patients (40%). NTR changed in the desired direction in 25 of 40 patients (63%). In the patients studied serially, NTP decreased an average 0.7 mm between 6 and 12 months (P = .018), and 0.6 mm between 12 and 24 months (P = .071). CONCLUSIONS: Decreased NTP and NTR were the most easily achieved surgical objectives. Maintaining or increasing NTP is less predictable. Typically, there is a progressive loss of NTP after surgery independent of the surgical goal. Cephalometric analysis is a useful tool to measure changes in NTP and NTR after septorhinoplasty.     

Farewell to bacteremia caused by endoscopic injection--effectiveness of a new injection catheter with a covered tip

BACKGROUND: Endoscopic injection has recently been reported as effective for several treatments. Because the common channel (suction and biopsy) is usually contaminated with aspirated gastrointestinal juice containing bacteria, often the tip of the injector needle is also. We report a new catheter needle with a covered tip designed to prevent bacteremia from endoscopic injection. METHODS: The new covered needle catheter (Clisco needle) has a 23-gauge retractable needle with a 3 mm extrusion in one lumen. Its distal tip is covered with rubber, blocking infiltration of contaminated gut juice. Ten of these catheters and 10 other disposable needles were inserted through the colonoscope's biopsy channel for 10 patients. Needle tips were cut off after extrusion, and bacteria cultured were counted by standard plate count method. RESULTS: All cultures from ordinary needles grew Escherichia coli, whereas only 3 new needles grew E. coli. Average counts of bacteria cultured from these 3 catheters and 10 disposable needles were 1-250 and 90-6.1 x 10(6), respectively. The difference was highly significant (p < 0.0001). CONCLUSIONS: This new covered needle catheter reduces contaminating bacteria in patients who require endoscopic injection and may prevent bacteremia without antibiotic prophylaxis.     

On the origin of microcracking behind a crack tip

Calculations based on both linear elasticity and small scale yielding in an elastic-plastic body indicate that large normal stresses exist behind the tip of the main crack and are related to the presence of microcracks which intersect a fracture surface. This concept is applied to the specific case of microcracks which intersect a mixed mode I/II fatigue crack in Ti-40 at. pct V alloy single crystals. The microcracks, which occur on {110} and {111} planes, are associated with the radial distribution of stresses normal to the observed microcrack plane. In the Ti-40V alloy examined, microcracking may occur by cleavage on rarely observed {110} and {111} planes because of the combination of large normal stresses and flow at the microcrack tip which is controlled by the stress field imposed by the main crack.     

Do-it-yourself pregnancy tests: the tip of the iceberg

The author is concerned over the increasing use of clinical testing kits by untrained personnel who do not have sufficient background to detect malfunctions and who do not understand the complex nature of the reactions involved. Often these untrained persons try to modify the procedures to suit themselves with catastrophic results. Pregnancy kits are the most widely used and the most abused. The package inserts do not always emphasize strongly enough the need to adhere strictly to stated procedures. The reputations of both commercial manufacturers of such kits and the profession of medical laboratory technology will suffer unless legislation is introduced to limit the use of such potentially dangerous kits to those staff fully trained to use them.     

Microsurgical medial plantar flap banking: a method of choice for digital tip injury?

Wright's FST and related statistics are often used to measure the extent of divergence among populations of the same species relative to the net genetic diversity within the species. This paper compares several definitions of FST which are relevant to DNA sequence data, and shows that these must be used with care when estimating migration parameters. It is also pointed out that FST is strongly influenced by the level of within-population diversity. In situations where factors such as selection on closely linked sites are expected to have stronger effects on within-population diversity at some loci than at others, differences among loci can result entirely from differences in within-population diversities. It is shown that several published cases of differences in FST among regions of high and low recombination in Drosophila may be caused in this way. For the purpose of comparisons of levels of between-population differences among loci or species which are subject to different intensities of forces that reduce variability within local populations, absolute measures of divergence between populations should be used in preference to relative measures such as FST.     

Stress concentration at a notch tip in unidirectional metal matrix composites

A method to calculate static stress concentration factors in the fibers at the tip of a rectangular notch in unidirectional metal matrix composites was presented based on the shear lag analysis for a two-dimensional (2-D) model. By using this method, the influences of matrix yielding, width and size of notch, and size of specimen on the stress concentration factors were described. Furthermore, this method was applied successfully to describe the load-COD curve and tensile strength of notched-boron/aluminum and alumina/aluminum composites.     

Phacoemulsification versus extracapsular cataract extraction: a comparative study of cell survival and growth on the human capsular bag in vitro

AIMS/BACKGROUND: Phacoemulsification is rapidly replacing conventional extracapsular cataract extraction (ECCE) as the method of choice for cataract surgery in the Western world. However, posterior capsule opacification (PCO) still remains the major postoperative complication, affecting 20-50% of patients, and results from persistent cell growth of epithelial cells remaining after surgery. This study aimed to compare cell survival and growth on capsular bags following ECCE and phacoemulsification surgery using an established human capsular bag culture system. METHODS: Sham ECCE and phacoemulsification cataract operations were performed on pairs of human donor eyes. Capsular bags were dissected free, pinned flat on a petri dish, and incubated with Eagle's minimum essential medium (EMEM) alone or EMEM supplemented with 10% fetal calf serum (FCS). Ongoing observations were made using phase contrast microscopy. RESULTS: Cell growth was observed across the posterior capsule of all preparations studied. It was found that there was no significant difference in the rate of cell growth on the posterior capsule with the two extraction methods, such that 50% confluency was achieved in 7.0 (SD 1.8) (n = 7) days for ECCE and 7.43 (2.1) (n = 7) days for phacoemulsification surgery. The physical changes to the capsule as a result of cell growth, such as wrinkling and capsular tensioning, were also seen in both groups. CONCLUSIONS: Cell survival and growth is dependent on the donor, rather than the surgical technique performed. There is no significant difference between phacoemulsification and ECCE surgery on the rate and nature of cell growth on the posterior capsule in vitro.     

Surgery of the nasal tip

To accurately interpret heart rate variability (HRV) including circadian rhythm from Holter ECG, the simultaneous assessment of physical activity, which significantly affects HRV, is essential. In this study, to obtain this simultaneous assessment, the fundamental problems in implementing an accelerometer in a commercial Holter recorder were studied. In a treadmill exercise, three axial outputs of an accelerometer showed highly linear correlations with the running speed (correlation coefficient; vertical 0.94, forward-backward 0.97, sideways 0.97, three-dimensional amplitude 0.96, n = 8). The vertical acceleration showed a slightly sigmoidal increase with speed. Against a slope change, no significant increase in acceleration was observed except in the forward-backward direction. Individual calibration was found to be needed for the accurate estimation of physical load from body acceleration. A simplified calculation with the sum of the three axial absolute values correlated highly with the three-dimensional (3D) acceleration which shows the most reliable response to motions in any direction (r = 0.98, the slope of the regression line = 0.97) and, with this relation, the estimated 3D amplitude showed a sufficient degree of agreement. This substituted calculation was used in the Holter recordings. To know the posture of subjects, a piezoresistive accelerometer with the function of clinometer was used in another study. From played-back Holter recordings, the R-R interval and body acceleration were simultaneously sampled. The serial changes of both the power spectra of HRV and the body acceleration were observed over a 24 h period. Some cases with an abnormally reduced high-frequency component (HF) of HRV at night or an unusually high HF in the daytime were explained by physical conditions estimated with the accelerometer. The simultaneous assessment of patients' physical state by the present method provides the accurate interpretation of circadian rhythm in HRV.