Central Connections of the Lacrimal Functional Unit.

PURPOSE: To study the contribution of each eye to the reflex tear response, after unilateral and bilateral topical anesthesia. METHOD: A closed-eye, modified Schirmer test was performed bilaterally in 8 normal subjects, in a controlled environment chamber set to 23°C, 45% relative humidity, and 0.08 m/s airflow. Eye drops were instilled into each eye 10 minutes before the Schirmer test. Experiments were as follows: 1) bilateral saline (control), 2) unilateral anesthesia (ipsilateral anesthetic; contralateral saline), and 3) bilateral anesthesia. RESULTS: There was no difference in between-eye wetting lengths in the saline control eyes (P = 0.394) or the bilaterally anesthetized eyes (P = 0.171). The wetting length was reduced in both eyes after bilateral anesthesia compared with saline controls (P = 0.001; P ≤ 0.0005). After unilateral anesthesia, the wetting length was reduced in the anesthetized eye compared with its saline control by 51.4% (P ≤ 0.0005) and compared with its fellow, unanesthetized eye (P = 0.005). The fellow eye value was also reduced compared with its saline control (P = 0.06). CONCLUSIONS: The wetting length was reduced by topical anesthesia, when instilled bilaterally and ipsilaterally. The latter response implies an ipsilateral, reflex sensory drive to lacrimal secretion. In the unanesthetized fellow eye, the reduction compared with its saline control was not quite significant. This implies a relative lack of central, sensory, reflex cross-innervation, although the possibility cannot entirely be ruled out. These results are relevant to the possibility of reflex lacrimal compensation from a normal fellow eye, in cases of unilateral corneal anesthesia.

Conventional and novel body temperature measurement during rest and exercise induced hyperthermia.

Despite technological advances in thermal sensory equipment, few core temperature (TCORE) measurement techniques have met the established validity criteria in exercise science. Additionally, there is debate as to what method serves as the most practically viable, yet upholds the proposed measurement accuracy. This study assessed the accuracy of current and novel TCORE measurement techniques in comparison to rectal temperature (TREC) as a reference standard. Fifteen well-trained subjects (11 male, 4 female) completed 60min of exercise at an intensity equating to the lactate threshold; measured via a discontinuous exercise test. TREC was significantly elevated from resting values (37.2±0.3°C) at the end of moderate intensity exercise (39.6±0.04°C; P=0.001). Intestinal telemetric pill (TPILL) temperature and temporal artery temperature (TTEM) did not differ significantly from TREC at rest or during exercise (P>0.05). However, aural canal temperature (TAUR) and thermal imaging temperature (TIMA) were both significantly lower than TREC (P<0.05). Bland Altman analysis revealed only TPILL was within acceptable limits of agreement (mean bias; 0.04°C), while TTEM, TAUR and TIMA demonstrated mean bias values outside of the acceptable range (>0.27°C). Against TREC, these results support the use of TPILL over all other techniques as a valid measure of TCORE at rest and during exercise induced hyperthermia. Novel findings illustrate that TIMA (when measured at the inner eye canthus) shows poor agreement to TREC during rest and exercise, which is similar to other 'surface' measures.

Incision-sparing management of canaliculitis.

PURPOSE: To report our results of canaliculitis treatment with our incision-sparing technique which includes dilation of the punctum and compression of the canaliculus to express the sulphur granules, curettage and irrigation of the canaliculus with antibiotic solutions, and topical antibiotic use. METHODS: The medical records of all patients treated for canaliculitis between October 2009 and March 2013 were rewiewed. The punctum of affected canaliculus was dilated under local anesthesia. Then, starting just distal to common canaliculus, the horizontal canaliculus was compressed along its entire length using either a forceps or a cotton tip applicator on the conjunctival surface and a curette on the skin. Compression was repeated until no more sulphur granules appeared and the swelling of the canaliculus disappeared. A chalazion curette was inserted into canaliculus to evacuate any residual concretions. The canaliculus were irrigated with antibiotic solutions and the patients were prescribed topical antibiotic solutions for one month Patients with follow-up less than 3 months after the intervention were excluded from the study. RESULTS: Nine patients met criteria for canaliculitis. There were 1 male and 8 female patients. Median age of the patients was 53 years (range 36-72 years). All patients had unilateral lower canaliculitis. Mean duration of the symptoms was 13.4 months (range 4-36 months). We followed up all patients for at least 3 months after the intervention. The signs and symptoms resolved completely in all patients within 1 month and recurrence was not observed in any patient. No patients reported epiphora after the procedure. CONCLUSION: Our incision-sparing technique is effective in the treatment of canaliculitis. We suggest that minimally invasive or incision-sparing techniques be attempted before canaliculotomy to decrease postoperative complications rates.

Rabbit lacrimal acinar cells in primary culture: morphology and acute responses to cholinergic stimulation.

PURPOSE: The rabbit lacrimal gland yields large numbers of viable acinar cells that, when exposed to carbachol, respond with accelerated protein release, fluid phase endocytosis (Lucifer yellow uptake), and Na/H antiport activation. The current study was undertaken to determine whether such cells exhibit similar responses after having been maintained in primary culture. METHODS: Cells were isolated from 2-kg, juvenile male New Zealand White rabbits and maintained in a supplemented DMEM/Ham's F-12 medium for up to 72 hours. RESULTS: Electron microscopy showed the organization of freshly isolated cells to be highly polarized, with secretory vesicles at one pole and nucleus at the other; vesicles were heterogeneous in size and in the electron density of their contents. The cells remained polarized after overnight culture, but the secretory vesicle population was more homogeneous in size and content, and the cells tended to aggregate. After 72 hours, roughly half the cells retained good morphology and cytoplasmic polarization, but the vesicles were enlarged and their contents less electron dense. Cells that had been maintained overnight responded to the addition of 10 microM carbachol with a 32.2% +/- 15.5% (n = 12, P < 0.04) increase in the total amount protein released during a standard 20-minute incubation. This represented a mean 125% increase in the temperature-dependent component of protein release. The protein secretory response was decreased to 14.6% +/- 6.1% (n = 3, P < 0.07) for cells that had been maintained for 72 hours. In the same samples, carbachol increased fluid phase endocytosis by 38.3% +/- 8.1% (P < 0.01) and 70.9% +/- 13.4% (P < 0.025), respectively. The protein secretory response was partially, and the endocytic response fully blocked by 1 mM atropine. CONCLUSIONS: This model could be useful as a simplified system in which to study regulation of acinar cell function over days, rather than hours, as is required in fresh tissue models.

Congenital nasolacrimal system obstruction.

A series of 132 children with congenital nasolacrimal system obstruction was prospectively randomized into three groups to determine the effectiveness of different modes of nonsurgical treatment. Massaging the nasolacrimal sac in a manner that increased hydrostatic pressure and ruptured the membranous obstruction was more effective (with a high degree of statistical significance) than simple massage or no massage at all. Of those children requiring nasolacrimal probing, a high success rate was found with simple obstructions in the nasolacrimal duct. Failure of probing was more common in canalicular obstructions or generally narrow nasolacrimal ducts. Silicone intubation of the nasolacrimal system is an effective way of treating cases not cured by probing.