Benjamin Shlomi

Anterior skull base surgery without prophylactic airway diversion procedures

OBJECTIVE Although anterior skull base surgery has become a relatively safe and effective procedure, postoperative complications remain a serious problem. One of the most devastating complications of anterior skull base procedures is tension pneumocephalus (TP). In order to prevent TP, authors have recommended the use of prophylactic airway diversion procedures, such as prolonged endotracheal intubation or prophylactic tracheostomy. However, these procedures may mask neurologic deterioration, delay treatment, and prolong rehabilitation. The purpose of this study was to determine the need for airway diversion procedures in anterior skull base surgery. STUDY DESIGN Eighty-five patients underwent anterior skull base operations through the subcranial approach without prophylactic airway diversion. Sixty-four patients underwent resection of tumors, 12 patients underwent repair of cerebrospinal fluid leak, 6 patients underwent surgery due to anterior skull base fungal infections, and 3 patients underwent anterior skull base reconstruction procedures. RESULTS The complication rate of TP was 1.2% (1/85). This complication rate is similar to that previously reported for operations performed with airway diversion procedures. CONCLUSION Prophylactic airway diversion procedures are unnecessary in routine anterior skull base operations. Airway diversion should be indicated only when factors that might predispose the patient to risk of TP have been identified (ie, chronic cough or obstructive pulmonary diseases).

Effects of the subcranial approach on facial growth and development

OBJECTIVE: To analyze the long-term effects of subcranial surgery for anterior skull base tumors on facial growth. STUDY DESIGN AND SETTING: Retrospective study (1994 to 2004) in a university-affiliated hospital. Of 108 patients who underwent a subcranial surgical approach for anterior skull base tumors, six adolescents and five young adults fulfilled study entry criteria for age and follow-up data availability (mean, 3.2 ± 2 years). Cephalometric x-ray films monitored postoperative facial growth. Anteriorly and posteriorly measured horizontal and vertical maxillary growth were compared with normal values. RESULTS: All subjects had superiorly positioned maxillae (shorter in patients with long-standing pathologies). The upper incisor teeth were proclined relative to the cranial base reference planes. All cephalometric changes were within a 10 percent deviation of normal values. CONCLUSIONS: Subcranial surgery for these tumors minimally affects vertical facial skeleton growth. Early surgery is essential for unaffected horizontal growth. SIGNIFICANCE: Guidelines for anterior skull base tumor surgery in adolescents and young adults.

Solid Keratocystic Odontogenic Tumor—Report of a Nonaggressive Case

Odontogenic keratocyst (OKC), which was originally described by Philipsen 1 in 1956, has distinctive clinical and histologic characteristics. The histologic features of OKC include a thin epithelial lining of uniform thickness, with palisading of basal cells and a thin corrugated layer of parakeratin. OKCs have a high recurrence rate, which can be attributed both to the high proliferative activity of the epithelial lining and to the extension along the bony cancellous spaces, which makes complete enucleation difficult. 2,3 In a recent report that reviewed hundreds of published cases, the recurrence rates ranged from 0% to 100%, with those undergoing with enucleation having the worst recurrence rates (0% to 56%), in contrast to those undergoing resection, with a recurrence rate of 0% in all reviewed series. The investigators explained this discrepancy by the differences in the length of the postoperative follow-up periods, operative techniques used, differences in cyst location, the presence or absence of infection, associated teeth, involvement of mucosa, lesion size, or inclusion of cases with Nevoid basal cell carcinoma syndrome. 4 In the 2005 edition of the World Health Organization Classification of the Head and Neck Tumors, the odontogenic keratocyst was reclassified from a cystic to a neoplastic lesion, and the term “keratocystic odontogenic tumor” (KCOT) was coined. 5 In very rare cases, KCOT has been described as a solid, rather than a cystic, lesion. Only 3 cases of solid KCOT have been previously reported; thus, information on its characteristics is minimal. However, it has been suggested in 2 of these reports that these solid variants might be clinically more aggressive than the more common cystic variant of KCOT. 6,7 Keratoameloblastoma is another rare odontogenic tumor, with microscopic features of both ameloblastoma and KCOT, 8 which bears significant overlap with features of solid KCOT, and should be considered in the differential diagnosis. The purpose of the present report is to present a case of solid KCOT that did not present with unusually aggressive behavior and to discuss in detail the histologic differential diagnosis with keratoameloblastoma.

Oral neurovascular hamartoma: a lesion searching for a name

BACKGROUND Neurovascular hamartoma (NVH), in particular in the oral cavity, is rarely described in the literature. The low number of cases may reflect a genuine rarity of the lesion, or it may be due to its being unrecognized and/or under-reported. OBJECTIVES To investigate clinical and microscopic features of oral NVH and to define microscopic diagnostic criteria with emphasis on the differential diagnosis. METHODS Archival cases diagnosed as oral NVH between 1999 and 2011 were retrieved; clinical and demographic data were collected, and a paired morphometric analysis was conducted, with each case of NVH a case of fibrous hyperplasia (FH) from the same oral location. The nerve bundle and blood vessel density were quantified in five microscopic fields at ×100 magnification. RESULTS The study group included 25 oral NVH, 11 men and 14 women, aged 6-76 years, (mean 44). The majority occurred in the tongue (54%), followed by the buccal mucosa and lower lip (17% each), clinically presenting as asymptomatic 0.25-2.5 cm exophytic masses. Microscopic characteristics included poorly circumscribed masses of closely packed nerve bundles and blood vessels in a loose matrix, containing minimal or no inflammation. The mean nerve bundle density was significantly higher in NVH (4.28 ± 1.26) in comparison with FH (0.27 ± 0.27), (P < 0.00001), and mean vessel density was significantly lower (5.98 ± 1.4 vs. 7.8 ± 1.9, respectively), (P < 0.0003). CONCLUSION Oral NVH may not be as rare as previously considered. Morphometric analysis demonstrated that NVH presents a separate distinct entity.

Primary Oral Malignancy Imitating Peri-Implantitis

PURPOSE To describe new cases of primary malignancy arising around dental implants. MATERIALS AND METHODS Three patients presented with asymptomatic lesions around longstanding dental implants that resembled peri-implantitis. One case was primary large B-cell lymphoma and the remaining cases were primary squamous cell carcinoma in patients with oral lichen planus. The literature was reviewed for cases mimicking peri-implantitis. RESULTS Of 42 implant-associated malignancies reported from 2000 through 2014, 85.7% were squamous cell carcinoma (69% primary and 9.4% metastatic). Most patients presented with pre-existing risk factors for oral cancer. Lymphoma was not associated with dental implants. CONCLUSIONS Primary and metastatic malignancies can occur in peri-implant mucosa, often with clinical and radiographic features resembling peri-implantitis. Clinicians should have a high index of suspicion for changes in peri-implant mucosa in patients with existing risk factors; however, rare cases such as lymphoma might present outside this risk population. Histopathologic analysis should be included in the management of selected peri-implant lesions to avoid delayed diagnosis of malignancy.

The Importance of Histopathological Diagnosis in the Management of Lesions Presenting as Peri-Implantitis

PURPOSE This study is a histopathological analysis of lesions clinically diagnosed as peri-implantitis (PI). MATERIALS AND METHODS This retrospective study included microscopic findings in 117 peri-implant biopsies from lesions presenting clinical and radiographic features of peri-implantitis. RESULTS The study group included 117 biopsies, mean age 55.2 years; 60.9% of biopsies were from failing implants during explantation, the remaining from surviving implants. All cases showed microscopic evidence for inflammation; however, although 41% exhibited only nonspecific inflammation, 29.9% exhibited actinomyces-related inflammation, 18.8% pyogenic granuloma (PG), and 10.3% giant cell granuloma (GCG). Differences in implant failure rates between pathological diagnostic groups were not statistically significant. Lesions with simple inflammation could not be distinguished clinically or radiographically from the potentially destructive lesions. CONCLUSIONS There were no clinical features which could distinguish PI with simple inflammation from potentially destructive lesions mimicking PI, such as GCG, PG, and actinomycosis. However, to control GCG and PG surgical procedures would be recommended, actinomycosis would indicate specific antibiotics, whereas in nonspecific inflammation, these measures may not be indicated. The results of the present study provide evidence for the importance of early microscopic examination of lesions presenting clinically as peri-implantitis, a step toward more accurate diagnosis and improved treatment of PI and lesions mimicking PI.

Extraocular muscle damage from dental implant penetration to the orbit

Purpose To demonstrate an unusual case of orbital trauma due to dental surgery complication. Observations An elderly patient who underwent dental implantation to the zygomatic bone was hospitalized in the ophthalmology department with impaired abduction of her right eye, also evident on ocular examination. Head computed tomography demonstrated damage to the lateral rectus and to the inferior oblique muscles. Clinical assessment determined these muscles could not be repaired and reattached. The extent of irreversible damage in the patient was permanent limitation in movement of her affected eye with subsequent strabismus. Conclusions and importance Accurate pre-operative planning of dental zygomatic implant insertion, as well as selecting the size and direction of the implant, are imperative. Moreover, performing surgery in multidisciplinary centers with oculofacial plastic surgeons in such cases, may reduce risk of this complication, make it a safer procedure, and allow immediate treatment when required.