Comparative Analysis of Various Materials Used for Mastoid Cavity Obliteration in Canal Wall Down Mastoid Surgery

To study the surgical result and efficacy of different methods of mastoid obliteration with cavity care. This prospective study included 60 patients who had cholesteatoma, conducted in the Department of Ear Nose and Throat (ENT), Institute of Medical Sciences, Banaras Hindu University, Varanasi from July 2015 to July 2017. The mastoid cavity was obliterated with either muscle flap/bone dust/hydroxyapatite. detailed history otoscopic examination was done pre-operatively and follow up were recorded at 1 month and 3 months in postoperative period. 60 patients were included, who underwent canal wall down mastoid surgery. each group muscle flap (group 1), bone dust (group 2) and hydroxyapatite (group 3) included 20 patients, age group 31-40 year with its maximum incidence of 43.3%, Preop PTA value were almost equal in all group but on comparison at 1 month in postoperative period significant improvement was present in group 1 versus 2(0.021) and group 2 versus 3(0.003) but not in group 1 versus 3. Although at 3 month there were significant improvement was present in all groups. The incidence of pain, discharge, giddiness and wax formation were markedly reduced and healing of cavities was early and better in obliterated cavities done by muscle flap and bone dust material as compared to hydroxyapatite cavities, at the end of 3 months. outcome and quality of life was better and almost equal in muscle flap and bone dust material group as compared to hydroxyapatite group.

Comparative Study of Various Techniques of Mastoid Obliteration following Canal Wall Down Mastoidectomy

The primary objective of mastoid obliteration is the eradication of the disease and prevention of its recurrence. We intend to evaluate the impact of mastoid obliteration using autologous materials on the achievement of a dry mastoid bowl and frequency of maintenance care and hearing outcome of the operated ear. This was a hospital-based, non - randomized, prospective study. The study was performed over a period of 2 years. The study was performed in the Department of ENT of a tertiary care teaching hospital. Patients of chronic otitis media - squamosal type underwent canal wall down mastoidectomy and patients were divided into 2 groups of obliterated and non-obliterated. The canal wall obliterated patients were further compared in 3 groups based on the technique of mastoid obliteration used - bone dust, musculo-periosteal flap and cartilage graft. 6 months post-operative mastoid cavity epithelisation based on oto-microscopy and hearing outcome based on pure tone audiometry findings were compared. Majority of patients at 6-months follow-up found that epithelization was most common status of mastoid cavity with musculoperiosteal flap and discharge was commonest with cartilage graft. Mastoid obliteration with autologous materials is a safe and effective method to achieve a dry, safe and useful ear. In this study, musculo-periosteal flap being significantly better in terms of a well epithelized cavity and hearing outcome.

Septal Bony Paste Graft: A Life-Saving Material in Rhinoplasty Camouflage

BACKGROUND

Although cartilage tissue is a priority material in both structural grafting and camouflage, in some special cases, there is not enough material for camouflage due to cartilage insufficiency after it is used in structural grafting. In these cases, it is vital that the bony parts of the septum be prepared as a paste graft and applied for camouflage.

METHODS

The author retrospectively reviewed 62 rhinoplasty patients in whom septal bony paste grafts were applied during surgery from April 2018 to December 2019. A total of 56 patients were female, and 6 were male. The average age was 28 years old (range 18 to 52). The follow-up period ranged between 12 and 29 months (mean: 20.5). Septal bony paste grafts were prepared using a microrasp attached to a motor system.

RESULTS

Septal bony paste grafts were used for camouflage of osteotomy lines in 59 patients, dorsum smoothing in 47 patients, camouflage of tip grafts in 36 patients, and camouflage of dorsal onlay grafts in 21 patients. No serious complications related to septal bony paste graft application, including functional or aesthetic complications, were encountered.

CONCLUSION

A septal bony paste graft can be applied for camouflage in rhinoplasty in cases where there is not sufficient cartilage tissue for this purpose. A microrasp attached to a motor system can be used for effective and rapid preparation of the septal bony paste graft.

LEVEL OF EVIDENCE IV

This journal requires that authors assign a level of evidence to each article. For a full description of these evidence-based medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

An Effective Method to Collect Bone Dust for Mastoid Cavity Obliteration

To compare the volume of cortical bone dust collected and the time taken for bone dust collection by using a self-devised bone dust collector and that by manual method using a metal scoop in patients undergoing modified radical mastoidectomy with mastoid cavity obliteration. A prospective study was done in 62 patients of cholesteatoma. They underwent canal wall down mastoidectomy. Mastoid cavity was obliteration was done using cortical bone dust collected after dividing the patients randomly into 2 groups: (1) using a collector device made using a mucous extractor fitted with a nylon mesh of size 1″ × 3″ attached to the suction tube, (2) collected manually by using a metal scoop. The time taken for the collection of bone dust was recorded and the volume of bone dust collected was measured and recorded. We found that the time taken for the collection of bone dust was significantly lower and the volume of bone dust collected was higher using a mucous extractor as compared to that by manual collection using a metal scoop. The suction based mucous extractor performed better in terms of both time taken for collection and also in the volume of cortical bone dust that was collected as compared to manual collection using a metal scoop. Therefore, we conclude from our study that using the suction based mucous extractor is a more effective method of cortical bone dust collection for mastoid cavity obliteration.

Particulate matter emissions during autopsies: a method to reduce exposure

Particulate matter emitted during autopsies can serve as a vector for numerous viruses or bacteria and can lead to infections. Reducing the exposure of those particles in indoor working environments is, therefore, an important issue. To assess the health risk for employees in forensic medicine, we measure particulate matter in the ambient air during autopsies by using an aerosol spectrometer. The autopsies were performed with either an ordinary oscillating saw or an adapted saw with a suction unit. The particle emissions from both saws were compared to each other in order to evaluate whether a technical adaption leads to a particle reduction. Furthermore, the particle exposure reduction by wearing a face mask and variations in the background concentration in the room were analyzed. High particle concentrations were measured while using the ordinary saw. By using the adapted saw or wearing a face mask, the particle exposure could mostly be avoided. On the majority of the working days, an increase in the background concentration could be observed. Based on this knowledge, the use of a proper suction unit and wearing a face mask during autopsies is necessary. Besides, it is important to have sufficient ventilation in the room so that long-lasting high background concentrations can be prevented.

Using a mixture of local bone dust and morselized bone as graft materials in single- and double-level ACDF

Background

Using a cage filled with local bone in anterior cervical discectomy and fusion (ACDF) can eliminate morbidities associated with autograft harvest from the iliac crest while achieving high fusion rates. However, there is still no consensus regarding the methods for using local bone grafts. This retrospective study was performed to compare the clinical and radiological outcomes of using a mixture of bone dust and morselized bone versus morselized bone alone in ACDF.

Methods

A retrospective study of 228 patients affected by cervical degenerative disease who had undergone single- or double-level ACDF between January 2014 and June 2018 was performed. Nanohydroxyapatite/polyamide-66 (n-HA/PA66) combined with morselized bone was used in 111 patients (group A: single-level ACDF in 51 patients and double-level ACDF in 60 patients), whereas the n-HA/PA66 cage combined with a mixture of bone dust and morselized bone was used in 117 patients (group B: single-level ACDF in 58 patients and double-level ACDF in 59 patients). The fusion rate, extent of cage subsidence, fusion segmental height (FSH), C2-7 lordosis, segmental sagittal alignment (SSA), 10-point visual analog scale (VAS) score, and Neck Disability Index (NDI) were compared between the two groups.

Results

The VAS score and NDI were significantly reduced after the operation in group A and group B. At the final follow-up, the fusion rate was 90.2 % (46/51) and 94.8 % (55/58) in patients treated with single-level ACDF in group A and group B, respectively (p > 0.05). In patients treated with double-level ACDF, bone fusion was achieved in 52 patients (86.7 %) in group A and 55 patients (93.2 %) in group B (p > 0.05). The fusion rate of single- and double-level ACDF was higher in patients in group B than those in group A at the 3-month, 6-month and 12-month follow-ups (p < 0.05). The extent of cage subsidence after single- and double-level ACDF was lower in patients in group B (1.5 ± 0.5 mm and 2.3 ± 0.8 mm, respectively) than in those in group A (1.8 ± 0.7 mm and 2.9 ± 1.4 mm, respectively) (p < 0.05). There was no significant difference between the two groups in the C2-7 lordosis, FSH, SSA, VAS score, or NDI before or after the operation (p > 0.05).

Conclusions

Using a mixture of local bone dust and morselized bone as cage-filling materials yielded comparably good clinical outcomes as using morselized bone alone in single- and double-level ACDF. However, the mixture graft of bone dust and morselized bone was more beneficial in promoting early fusion and reducing cage subsidence.

The Risk of Spread of Infection During Craniotomy/Craniostomy on Patients with Active Coronavirus Disease 2019 (COVID-19) Infection: Myth or Fact?

OBJECTIVES

Craniotomies/craniostomies have been categorized as aerosol-generating procedures and are presumed to spread coronavirus disease 2019 (COVID-19). However, the presence of severe acute respiratory distress syndrome coronavirus 2 virus in the generated bone dust has never been proved. Our objective is to evaluate the presence of virus in the bone dust (aerosol) generated during emergency neurosurgical procedures performed on patients with active COVID-19. This would determine the true risk of disease transmission during the surgery.

METHODS

Ten patients with active COVID-19 infection admitted to our institute in 1 month required emergency craniotomy/craniostomy. The bone dust and mucosal scrapings form paranasal sinuses (if opened) collected during these procedures were tested for the virus using reverse transcription polymerase chain reaction. The entire surgical team was observed for any symptoms related to COVID-19 for 14 days following surgery.

RESULTS

Nine patients had moderate viral load in their nasopharyngeal cavity, as detected on reverse transcription polymerase chain reaction. None of the samples of bone dust from these 10 patients tested positive. Mucosal scrapping obtained in 1 patient in which mastoid air cells were inadvertently opened tested negative as well. No health workers from the operating room developed COVID-19-related symptoms.

CONCLUSIONS

The bone dust generated during craniotomy/stomy of active patients does not contain the virus. The procedure on an active patient is unlikely to spread the disease. However, a study with larger cohort would be confirmatory.

Minimizing aerosol bone dust during autopsies

When sawing bone for medical or medico-legal procedures, fine, airborne dust is produced (aerosols) that can pose a health hazard when inhaled. The aim of this study was to determine the influence of saw blade frequency and contact load, bone condition, test environment, and saw blade type, on the production of aerosol particles. A custom test setup was designed, manufactured and used in 8 bone sawing experiments, using a particle counter to determine the production of aerosol particles while varying the 5 chosen parameters. The number of counted particles was highest with higher saw blade frequencies, lower saw blade contact loads, in dry completely skeletonized bone compared to fresh bone, and using an electrical oscillating saw compared to hand-sawing. Under all conditions, the high amount of aerosol counted posed potential health risks. The ventilation system that we tested was adequate in removing the produced particles, but these high-tech systems are not always available in developing countries or emergency situations. The production of aerosols can be reduced by optimizing the sawing parameters. However, even the lowest number of aerosol particles counted during the current study was high enough to cause potential health risks to practitioners. Safety precautions should be taken, such as external ventilation, proper breathing gear, and adequate protocols, to truly minimize the risk in all bone sawing scenarios.

A Self-Made, Reusable, and Adjustable Device for Making Burr Hole Bone Plugs: Doing More with Less

BACKGROUND

Burr hole craniotomy is a daily procedure in neurosurgery. Defects after burr hole craniotomies will not spontaneously heal and can result in skin dents and cosmetic dissatisfaction. We have introduced a self-made, reusable, and adjustable bone plug packer to use in the repair of burr holes via packing of autologous bone dust. Our bone plug packer is free of charge and can be readily available in neurosurgical operating rooms.

METHODS

We have produced a stainless steel bone packer device that can be assembled without the use of a special wrench. The instrument consists of a container plate and a main cylinder for packing, in which an adjustable airtight piston is placed to compress the bone dust and create a bone plug of the desired dimensions.

RESULTS

Some recent studies have shown that burr holes filled by autologous bone dust will result in good cosmetic and osteogenic outcomes. Although we did not perform a long-term follow-up assessment of the burr holes filled with bone plugs, in the short term, we have not seen any local reactions or infections in our patients. The autologous bone plug is a more affordable and available option with no technical or clinical complications in the short term.

CONCLUSION

We have introduced a practical, convenient, and cost-effective bone packer device. Bone plugs formed using our device can be a potential substitute for expensive covering materials in countries with limited access to other repair options. Providing proper evidence will require the performance of large studies to assess our suggested method in the long term and, possibly, compare it with the usual options in controlled studies.

[Clinical application of a self-developed bone dust collector in mastoid cavity obliteration following mastoidectomy]

Objective: To introduce a self-developed bone dust collector designed by the authors and evaluate its efficiency in mastoid obliteration following mastoidectomy. Methods: Consecutive patients, from April 2017 to March 2018, who prepared to receive mastoidectomy were randomly divided into two groups, and in each group the bone dust was harvested by self-developed bone dust collector or by conventional used method respectively in mastoidectomy. The amount of the harvested bone dust and the time consumed in the collecting procedure were compared between two groups. The infection of the bone dust after mastoid obliteration was also evaluated during follow up. Results: 33 patients were recruited in bone dust collector group, and 31 patients in conventional method group.There is no significance of difference between two groups in sex ratio, age and pneumatization of mastoid cells (P>0.05 for all). The median amount of bone dust harvested by bone dust collector was significantly larger than that collected by conventional method (1.8 g vs 1.1 g, P<0.05). The median time spent in bone dust collector group was significantly shorter than that spent in conventional method group (4 minutes vs 6 minutes, P<0.05). No bone dust infection was found in the follow-up in all patients. Conclusion: The present self-developed bone dust collector is a easy and useful apparatus which can significantly improve the efficiency of collecting bone dust in mastoidectomy.

Aerosol production during autopsies: The risk of sawing in bone

When sawing during autopsies on human remains, fine dust is produced, which consists of particles of sizes that may fall within the human respirable range, and can act as vectors for pathogens. The goal of this study was to explore the potential effects of saw blade frequency and saw blade contact load on the number and size of airborne bone particles produced. The methodology involved the use of an oscillating saw with variable saw blade frequencies and different saw blade contact loads on dry human femora. Released airborne particles were counted per diameter by a particle counter inside a closed and controlled environment. Results corroborated with the hypotheses: higher frequencies or lower contact loads resulted in higher numbers of aerosol particles produced. However, it was found that even in the best-case scenario tested on dry bone, the number of aerosol particles produced was still high enough to provide a potential health risk to the forensic practitioners. Protective breathing gear such as respirators and biosafety protocols are recommended to be put into practice to protect forensic practitioners from acquiring pathologies, or from other biological hazards when performing autopsies.

The Efficacy of Local Autologous Bone Dust: A Systematic Review

STUDY DESIGN

A systematic review of bone dust as an autologous bone graft to encourage osseous fusion.

OBJECTIVE

To identify and review studies that report on the therapeutic potential of bone dust. The research question was structured as follows: populations-animal and human sources of bone dust harvested using burrs; interventions-autologous bone dust compared with other clinically utilized bone graft options; outcomes assessed-(1) in vitro cell viability, cell differentiation, and osteogenic potential and (2) clinical efficacy in the form of fusion rates as assessed using plain radiographs; study designs-in vitro, preclinical in vivo and clinical studies investigating the therapeutic potential of bone dust, harvested by burring, are included in this systematic review.

SUMMARY OF BACKGROUND DATA

Little is known about the efficacy of bone dust, generated during burring of local bone in spine surgery, as a bone graft to encourage osseous union.

METHODS

A systematic search was conducted in Medline, PubMed, OVID, Scopus, and Cochrane library. The following key words were used: bone dust, bone burring, bone paste, bone pate.

RESULTS

A total of 285 studies were reviewed. Fourteen articles were identified as relevant for inclusion in this systematic review. Current evidence suggests that bone dust retains osteogenic properties, but limited information is available regarding the osteoinductive potential of bone dust.

CONCLUSION

Bone dust represents a free source of autologous bone, which can be easily collected during the time of surgery and used as an augment to aid osseous fusion. Further research is required to evaluate the osteoinductive potential of bone dust. The retained growth factors in bone dust may potentially induce local osteoprogenitor cells to proliferate and mineralize to form new bone.

Comparison of the osteogenic potential of bone dust and iliac bone chip

BACKGROUND CONTEXT

There is no comparative study of the in vitro and in vivo osteogenic potential of iliac bone chips (autogenous iliac cancellous bone chips) compared with bone dusts generated during the decortication process with a high-speed burr in spine fracture or fusion surgery.

PURPOSE

To compare the osteogenic potential of three sizes of bone dusts with iliac bone chips and to determine whether bone dusts can be used as a bone graft substitute.

STUDY DESIGN

In vitro and in vivo study.

METHODS

Bone chips were harvested from the posterior superior iliac spine and bone dusts from the vertebrae of 15 patients who underwent spinal fracture surgery. Bone dust was divided into three groups: small (3 mm), middle (4 mm), and large (5 mm) according to the size of the burr tip. A comparison was made using a cell proliferation assay, alkaline phosphatase (ALP) activity, the degree of mineralization in an in vitro model, and radiographic and histologic studies (the change of absorbable area and tissue density) after implantation of the various materials into back muscles of nude mice.

RESULTS

Although all three bone dust groups were less active with regard to cell proliferation, ALP activity, and the degree of mineralization, than were bone chips, they still exhibited osteogenic potential. Furthermore, there was no significant difference among the three bone dust groups. The three bone dust groups did show greater absorbable area and change of the tissue density than did the iliac bone chip group. Again, there was no significant difference among the three bone dust groups in this regard. Histologically, specimens from the bone dust groups had a higher osteoclast cell number than specimens from the iliac bone chip group.

CONCLUSIONS

The osteogenic potential of bone dusts is lower than that of iliac bone chips, and the absorption speed of bone dusts in vivo is faster than that of iliac bone chips. The increased resorption speed appeared to result from an increase in osteoclast cell number. Therefore, caution needs to be used when surgeons employ bone dust as a bone graft substitute.

Mastoid obliteration versus open cavity: a comparative study

A chronic discharging ear has been a perpetual problem and a source of worry to the otologists for centuries because of its high rate of morbidity. Active squamous chronic otitis media is a commonly encountered disease entity which requires prompt surgical management. The surgical procedure most commonly employed is modified radical mastoidectomy. This results in an 'open' cavity with its attendant problems of recurrent breakdown and discharge. Mastoid obliteration technique would appear to be the best solution for these cavity problems. Forty cases of active squamous chronic otitis media were studied. The patients were randomly divided into two groups of 20 each. The group of 20 controls had an open mastoid cavity. Out of the 20 cases, patients were divided in four groups of 5 each. For each group the mastoid cavity was obliterated with cartilage, bone dust, hydroxyapetite and Singapore swing. Healing of the cavity and the associated cavity problems in terms of pain, discharge, giddiness and wax formation, were assessed. The incidence of pain, discharge, giddiness and wax formation was markedly reduced in obliterated cavities as compared to open cavities. Healing of the cavity as evidenced by epithelialisation, at the end of 6 months, was better in those ears where cavity was obliterated (90%) as compared to those with open cavity (70%). Cases obliterated with bone dust and Singapore swing had better and early epithelialisation (100%) as compared to cartilage and hydroxyapetite (80%).