Effect of mitomycin C on the size of antrostomy after endoscopic sinus surgery

Safety profile and efficacy of high-dose topical mitomycin-C for choanal atresia repair: A prospective cohort study

OBJECTIVES

To study the effect of dose-adjusted mitomycin-c (MMC) on the recurrence rate of choanal atresia (CA), and the complication rate associated with this concentration.

METHODS

This prospective cohort study was conducted between May 2012 and March 2020 at a tertiary referral center. It included patients of all ages who were diagnosed with CA and scheduled to undergo surgical repair. The MMC group received 4.0 mg/mL of topical MMC. Both groups were followed up for the surgical outcomes and complication rates.

RESULTS

Twenty-one patients (15 females) underwent 25 CA repair procedures. The mean age was 44.85 months (standard deviation = 72.85). MMC was used in 12 (57.1%) of 21 patients. Revision CA repair was warranted in three of the nine patients who did not receive topical MMC compared to one of the 12 patients who received topical MMC. The MMC group required 1.08 ± 0.29 surgeries (range, 1-2), whereas the non-MMC group required 1.44 ± 0.73 surgeries (range, 1-3). Functional success was achieved in 17 (81%) patients who remained symptom-free until their last follow-up visit.

CONCLUSION

High-concentration MMC was considered safe in the pediatric and adult populations. Although high-concentration MMC could reduce the need for revision surgery, further studies are required to determine whether the effect is significant in a larger sample population.

Particularities and Clinical Applicability of Saccharin Transit Time Test

Introduction  The importance of mucociliary clearance (MCC) for the respiratory system homeostasis is clear. Therefore, evaluating this defense mechanism is fundamental in scientific research and in the clinical practice of pulmonology and of associated areas. However, MCC evaluation has not been so usual due to the complexity of methods that use radiolabeled particles. Nevertheless, as an interesting alternative, there is the saccharin transit time (STT) test. This method is reproducible, simple to perform, noninvasive, does not demand high costs, and has been widely used in studies of nasal MCC. Although the STT test is widely used, there is still lack of a detailed description of its realization. Objective  The present literature review aims to provide basic information related to the STT test and to present the findings of the previous studies that used this method, discussing variations in its execution, possible influences on the obtained results and limitations of the method, as well as to relate our experience with the use of STT in researches. Data Synthesis  There are several factors that can alter the results obtained from STT tests, which would raise difficulties with proper interpretation and with the discussion of the results among different studies. Conclusions  Saccharin transit time is a widely used method for the evaluation of nasal MCC, and therefore, the standardization related to the previous and concurrent to test orientations, and also its execution, become essential to improve its accuracy, and allow comparisons among different studies.

Comprehensive review on endonasal endoscopic sinus surgery

Endonasal endoscopic sinus surgery is the standard procedure for surgery of most paranasal sinus diseases. Appropriate frame conditions provided, the respective procedures are safe and successful. These prerequisites encompass appropriate technical equipment, anatomical oriented surgical technique, proper patient selection, and individually adapted extent of surgery. The range of endonasal sinus operations has dramatically increased during the last 20 years and reaches from partial uncinectomy to pansinus surgery with extended surgery of the frontal (Draf type III), maxillary (grade 3-4, medial maxillectomy, prelacrimal approach) and sphenoid sinus. In addition there are operations outside and beyond the paranasal sinuses. The development of surgical technique is still constantly evolving. This article gives a comprehensive review on the most recent state of the art in endoscopic sinus surgery according to the literature with the following aspects: principles and fundamentals, surgical techniques, indications, outcome, postoperative care, nasal packing and stents, technical equipment.

[Orbital complications of sinusitis]

PURPOSE

Orbital complications of sinusitis are rare but serious, with potential functional and even fatal consequences. The purpose of this work is to study the epidemiological, clinical and paraclinical features of the orbital complications of sinusitis, as well as the various treatment modalities and clinical course.

PATIENTS AND METHODS

We report the results of a retrospective study of 34 cases of orbital complications of sinusitis, collected between 1998 and 2009.

RESULTS

Mean age was 19 years 3 months, with a clear male predominance. No predisposing factors were found. All patients presented with periorbital edema. In addition to periorbital edema, ophthalmological examination also revealed: proptosis in 19 patients, decreased visual acuity in eight patients and ocular motility disturbances in 10 patients. All patients underwent emergent facial CT, two patients underwent orbital ultrasound, and one underwent magnetic resonance imaging. Initial treatment was based on empiric intravenous antibiotic therapy. Orbital drainage was performed in 20 patients. Sinus drainage was performed in 16 patients (14 cases during the acute phase) with a middle meatotomy in all cases. The initial response was favorable in 97.5% of cases. One patient had a recurrence. Mean follow-up was 11 months.

CONCLUSION

Orbital complications of sinusitis are a diagnostic and therapeutic emergency. Imaging helps guide management. Directed treatment and early management can improve mortality and morbidity.

Evidence-based applications of mitomycin C in the nose

BACKGROUND

Mitomycin C (MMC) is an antimitotic drug that may, when applied topically, prevent postoperative stenosis. Its use remains controversial. This review aims to provide otolaryngologists with an update of the evidence on the applications of this agent in the nose and sinuses.

METHODS

A systematic review was performed. Inclusion criteria were as follows: English literature, original articles, reviews, and case series. Exclusion criteria were as follows: animal and in vitro studies, nonendoscopic and nonsinonasal applications of MMC, and external lacrimal surgery. Studies that used other ways of dilating stenoses in conjunction with MMC were excluded.

RESULTS

Out of 48 studies published, 9 fulfilled our inclusion criteria, totaling 322 patients. Eighty-five percent were primary and 15% were revision cases. Follow-up ranged from 1 to 42 months. Main outcome measures used were endoscopic examination, anatomical measurements, radiological scoring systems, dye tests, and subjective symptom resolution. Main overall outcomes from studies where extrapolation of data was feasible were (1) patency rate, which ranged from 63% to 94.4% (mean, 81.3%); (2) adhesions: 5.1% (MMC) vs 15.05 (control); and (3) stenosis: 14.05% (MMC) vs 32.6% (control).

CONCLUSIONS

There appears to be a favorable short-term effect of MMC, but no robust evidence regarding long-term prevention of restenosis. Larger homogenous and multicenter randomized trials are needed to assess the long-term effects of MMC in sinonasal surgery.

The effects of repetitious topical use of mitomycin C on antrostomy patency in maxillary antrostomy created rabbit model

The aim of our study was to investigate the effect of the topical use of mitomycin C (MMC) intraoperatively in single dose and intra-postoperatively in two doses on the narrowing of antrostomy in maxillary rabbit sinus antrostomies created experimentally. And also to determine the local and systemic side effects of topical MMC. With this objective, 0.6 mg/ml MMC was used to the first group at single dose and to the second group intraoperatively and on third day postoperatively in two doses topically for 5 min. After 8 weeks, although the mean area of antrostomy was larger than that in the control side in the first group, which received single dose MMC, the difference was not statistically significant (p = 0.287). The second group received two doses, and the antrostomy areas were found to be significantly larger than the controls (p = 0.05). Overall, the sides that received MMC were significantly larger (p = 0.029). From the point of histopathological examination of the tissue, it was seen that two-dose MMC increased the edema indicating inflammation and antrostomy resolved with normal respiratory tract epithelium. It was shown by measuring the blood values that nephrotoxic and myelosupressant effect of MMC occurring in systemic use did not occur with single or double dose topical use. Our results demonstrate that even if the number of cases was low, two doses of topical MMC usage prevent the narrowing of antrostomy while single dose MMC does not. And two-dose topical MMC usage does not have local and systemic side effects.

Topical use of MMC in the upper aerodigestive tract: a review on the side effects

Not much is known about the side effects of mitomycin C (MMC), an anti-fibrogenetic agent, in the upper aerodigestive tract. However, its use in ophthalmology is widely known and without quantitatively important side effects. A literature review was performed for side effects of MMC in the upper aerodigestive tract. Forty-six articles, describing the use of MMC to prevent scarring, were retracted from PubMed. Thirty-two are human studies. MMC is used in different concentrations (0.1–10 mg/ml) with different application times (2–5 min) and frequencies (up to 4 times). Five hundred and thirty-eight patients were included in those publications, of whom 19 developed side effects (3.53%). No side effects developed in studies, where post-application irrigation with saline was reported. The longest mean follow-up period is 75.5 months. Direct relations between the reported side effects and MMC seem absent in most studies. Serious complications seem to occur when MMC is used in high concentrations. Unfortunately, sometimes crucial information is lacking. One patient was described who supposedly developed laryngeal carcinoma after repeated treatment of hyperkeratosis and anterior commissure webbing. Animal studies show that excessive fibrin production can lead to acute airway obstruction. In conclusion, topical application of MMC on a wound with consecutive irrigation with saline can be performed safely to prevent scar formation in circular structures of the upper aerodigestive tract. Long-term yearly control of the application site seems advisable.

Study of Wound Healing in Rats Treated with Topical and Injected Mitomycin C

Objectives:

Mitomycin C, a widely used chemotherapeutic drug, has been proposed as a potential adjuvant for the control of scar tissue in surgical wounds because of its capacity to inhibit fibroblast proliferation. The current study used a combination of topical and injected mitomycin C to slow the healing process of surgical wounds in rats.

Methods:

An experimental model of surgical wounding at the dorsum of rats was used. A total of 43 animals were subdivided into 3 groups: Control, topical mitomycin C, and a combination of topical treatment and intradermal injections of the drug at 30 and 60 days after the initial topical treatment. After 3 months, the animals were painlessly sacrificed and the surgical scars were removed for microscopic analysis.

Results:

The group that received only topical mitomycin C presented milder inflammatory signs and consequently had a less intense healing process than the control group. The group treated with a combination of both topical and injected mitomycin C presented results comparable to those of the control group.

Conclusions:

The toxic characteristics of mitomycin C were most likely responsible for the greater tissue damage that occurred when it was used in the injected form, causing increased scar tissue formation. Mitomycin C slows the healing process of surgical wounds when used topically, but causes enhanced scar tissue formation when injected.

Progress in surgical management of chronic rhinosinusitis and nasal polyposis

Endoscopic sinus surgery (ESS) remains the treatment of choice for medically refractory chronic rhinosinusitis (CRS) with or without nasal polyposis (NP). ESS has undergone review, reassessment, and substantial refinement. Several advances (eg, powered instrumentation, image guidance, adjunctive intraoperative procedures) have expanded the scope of cases amenable to ESS, decreased operative time and intraoperative blood loss, and improved safety. Procoagulant nasal/sinus packing and refinements of technique have decreased the need for postoperative removal of packing, thus decreasing morbidity. Methods to reduce synechia formation (ie, mitomycin-c) have been explored, with mixed results. Novel methods of sinusotomy (eg, balloon catheter dilatation of the sinus ostia) have had limited but interesting short-term results. We can expect further advances in ESS with better patient outcomes. However, continued elucidation of the underlying pathophysiology of CRS and NP are essential to long-term improvement.