Assessment of the influence of viscoelasticity of cornea in animal ex vivo model using air-puff optical coherence tomography and corneal hysteresis

Application of the air-puff swept source optical coherence tomography (SS-OCT) instrument to determine the influence of viscoelasticity on the relation between overall the air-puff force and corneal apex displacement of porcine corneas ex vivo is demonstrated. Simultaneous recording of time-evolution of the tissue displacement and air pulse stimulus allows obtaining valuable information related in part to the mechanical properties of the cornea. A novel approach based on quantitative analysis of the corneal hysteresis of OCT data is presented. The corneal response to the air pulse is assessed for different well-controlled intraocular pressure (IOP) levels and for the progression of cross-linking-induced stiffness of the cornea. Micrometer resolution, fast acquisition and noncontact character of the air-puff SS-OCT measurements have potential to improve the in vivo assessment of mechanical properties of the human corneas.

Ophthalmic complications of endoscopic sinus surgery

Introduction

The proximity of the paranasal sinuses to the orbit and its contents allows the occurence of injuries in both primary or revision surgery. The majority of orbital complications are minor. The major complications are seen in 0.01–2.25% and some of them can be serious, leading to permanent dysfunction.

Objective

The aim of this study was to determine the risk and type of ophthalmic complications among patients operated due to a chronic rhinosinusitis.

Methods

This is a retrospective study of 1658 patients who underwent endoscopic sinus surgery for chronic rhinosinusitis with or without polyps or mucocele. Surgeries were performed under general anesthesia in all cases and consisted of polyps’ removal, followed by middle metal antrostomy, partial or complete ethmoidectomy, frontal recess surgery and sphenoid surgery if necessary. The ophthalmic complications were classified according to type, frequency and clinical findings.

Results

In our material 32.68% of the patients required revision surgery and only 10.1% had been previously operated in our Department. Overall complications occurred in 11 patients (0.66%). Minor complications were observed in 5 patients (0.3%) with the most frequent being periorbital ecchymosis with or without emphysema. Major complications were observed in one patient (0.06%) and were related to a lacrimal duct injury. Severe complications occurred in 5 cases (0.3%), with 2 cases and referred to a retroorbital hematoma, optic nerve injury (2 cases) and one case of extraocular muscle injury.

Conclusions

Orbital complications of endoscopic nasal surgery are rare. The incidence of serious complications, causing permanent disabilities is less than 0.3%. The most important parameters responsible for complications are extension of the disease, previous endoscopic surgery and coexisting anticoagulant treatment.

Induction therapy with carboplatin/paclitaxel followed by concurrent carboplatin/paclitaxel and dose-escalating conformal radiotherapy in the treatment of locally advanced, unresectable non-small cell lung cancer: preliminary report of a phase I trial

Locally advanced non-small cell lung cancer is optimally managed with chemotherapy and thoracic irradiation, although the most appropriate strategy is not yet defined. In this phase I trial, we use two 21-day cycles of induction chemotherapy with paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) (225 mg/m2 over 3 hours) and carboplatin (area under the concentration-time curve = 6) followed by concurrent weekly paclitaxel (45 mg/m2/wk x 6) and carboplatin (area under the concentration-time curve = 2/wk x 6) and thoracic irradiation. Patients undergo three-dimensional treatment planning (conformal radiotherapy) to define the cancer target volume precisely. The phase I question being addressed in this study is the maximum tolerated radiation dose given concurrently with low-dose paclitaxel and carboplatin. The initial radiation dose is 60 Gy, with dose escalations to 66 Gy, 70 Gy, and 74 Gy being planned. Ten patients have been entered thus far (eight men and two women). Their median age is 67 years (range, 59 to 78 years), and none of the patients has had greater than 5% pretreatment weight loss. Seven of 10 are evaluable for response to induction carboplatin and paclitaxel, with a response rate of 57% (three partial responses and one minor response). Three patients had stable disease and none of the patients had evidence of progressive disease during induction chemotherapy. Three patients have completed all treatment at 60 Gy and one has completed all treatment at 66 Gy. Three of the four patients have had partial responses (75%), with the remaining patient having stable disease. Toxicity in the concurrent chemoradiotherapy portion of the trial thus far has consisted of grade 3 neutropenia in one patient and grade 4 lymphocytopenia in all four patients. No grade 3 or 4 nonhematologic toxicity has been seen. The trial data are not yet mature enough to report on survival. Accrual and treatment is continuing at the 66 Gy radiation dose level.