Predictive Value of Swab Cultures for Cryopreserved Flaps During Delayed Cranioplasties.

OBJECTIVE: To assess the predictive value of swab cultures of cryopreserved skull flaps during cranioplasties for surgical site infections (SSIs). METHODS: A retrospective review was conducted of consecutive patients who underwent delayed cranioplasties with cryopreserved autografts between 2009 and 2017. The results of cultures obtained from swabs and infected surgical sites were assessed. The accuracy, sensitivity, and specificity of swab cultures for SSIs were evaluated. RESULTS: The study included 422 patients categorized into two groups, swab and nonswab, depending on whether swab cultures were implemented during cranioplasties. The overall infection rate was 7.58%. No difference was seen in infection rates between groups. There were 18 false-positive and no true-positive swab culture results. All bacteria between swab cultures and SSI cultures were discordant. Meanwhile, there were 19 false-negative swab cultures. The results showed high specificity but low sensitivity for swab cultures to predict SSI occurrence and the pathogens. CONCLUSIONS: Owing to low accuracy and sensitivity, swab cultures of cryopreserved autografts should not be routinely performed during delayed cranioplasties.

Pedicled Multifidus Muscle Flap To Treat Inaccessible Dural Tear In Spine Surgery: Technical Note And Preliminary Experience.

OBJECTIVE: To assess the usefulness, feasibility, and limitations of pedicled multifidus muscle flaps (PMMFs) for the treatment of inaccessible dural tears during spine surgery. METHODS: The technique of PMMF harvesting was investigated together with relevant anatomy. We prospectively evaluated 8 patients treated with the PMMF technique between January 2017 and December 2019. Results were compared with a retrospective series of 9 patients treated with a standard technique between January 2014 and December 2016. Inclusion criteria were inaccessible dural tear or dural tear judged not amenable to direct repair because of tissue loosening. Exclusion criteria were surgical treatment of intradural disease. Clinical and demographic data of all patients were collected. Clinical evaluations were performed according to American Spinal Injury Association criteria and Oswestry Disability Index. Preoperative and postoperative computed tomography was performed in all patients. The primary end point was wound healing (cerebrospinal fluid leakage, infection, and fluid collection); secondary end points were neurologic outcome and complications. RESULTS: Control group: 1 death as a result of wound infection secondary to cerebrospinal fluid fistula and 2 patients needed lumbar subarachnoid drain; neurologic outcome: 3 patients improved and 6 were unchanged. Flap group: no wound-related complications were observed; neurologic outcome: 3 patients improved and 5 were unchanged. No flap-related complications were described. Flap harvesting was feasible in all cases, with an average 20 minutes adjunctive surgical time. CONCLUSIONS: The PMMF technique was feasible and safe; in this preliminary experience, its use is associated with lower complications as a result of dural tears but larger series are needed to confirm its effectiveness.

Bone Flap Resorption Associated with Indolent Propionibacterium acnes Infection After Cranioplasty: Case Report with Pathological Analysis.

BACKGROUND: Autologous bone resorption is a frequent complication of cranioplasty, often necessitating reoperation. The etiology of this phenomenon is unknown, although it has recently been associated with indolent Propionibacterium acnes infection. CASE DESCRIPTION: A 59-year-old man initially presented with a traumatic acute subdural hematoma treated with emergent decompressive hemicraniectomy and hematoma evacuation. His bone flap was cryopreserved. He underwent cranioplasty with autologous bone 3 months later. Over the subsequent 14 months, serial imaging demonstrated progressive bone flap resorption, ultimately requiring repeat cranioplasty with a custom allograft. Although there was no evidence of infection at the time of repeat cranioplasty, routine culture swabs were taken and grew P. acnes after the patient had been discharged home. Pathologic analysis of the fragments of the original bone flap that were removed demonstrated osteonecrosis with marrow fibrosis but no evidence of inflammation or infection. He was treated with 6 weeks of intravenous antibiotics and had no evidence of infection at 8-month follow-up. CONCLUSIONS: Indolent P. acnes infection can precipitate autologous bone flap resorption. While the mechanism of this is unknown, pathologic analysis of a partially resorbed bone flap in the setting of an indolent P. acnes infection found no evidence of an infectious process or inflammation within the bone. Further studies are needed to elucidate the mechanism of action of P. acnes in bone flap resorption.

Effects of Bathing Habits on Postoperative Wound Complications Following Sacrococcygeal Pilonidal Sinus Surgery: A Retrospective Analysis of 67 Adolescent Patients.

INTRODUCTION: Sacrococcygeal pilonidal sinus disease generally affects young people and impacts their quality of life. Few published studies assessing the characteristics of the disease in the adolescent population exist. OBJECTIVE: In this paper, the authors aim to evaluate the effects of bathing habits on wound complications in adolescent patients following Karydakis flap surgery for sacrococcygeal pilonidal sinus. MATERIALS AND METHODS: The medical records of 79 adolescent patients who underwent sacrococcygeal pilonidal sinus surgery between January 2014 and December 2017 at the Surgery Clinic of Malatya State Hospital (Malatya, Turkey) were evaluated retrospectively. Following exclusion, 67 patients were evaluated for demographics, body mass index (BMI), previous abscess formation, bathing frequency, number of sinus pits, and postoperative wound infection and dehiscence. The total follow-up time for the 67 patients was 90 days. RESULTS: The BMIs of patients with previous abscess formation were significantly higher (P = .029). In the cases with abscess, the number of pilonidal sinus pits was significantly higher (P = .039) There was a statistically significant difference between postoperative complication rates according to the number of baths per week. Wound infection rates were found to be higher in patients who bathed more than twice weekly during the 28 days after surgery (P = .005). No statistical significance was observed in complication rates from days 28 to 90 after the surgery between those who bathed twice weekly and more than twice weekly (P > .05). CONCLUSIONS: Postoperative wound complications in adolescent patients treated with Karydakis flap surgery for sacrococcygeal pilonidal sinus are more frequent in those who bathe more than twice weekly during the first 28 days postoperatively.

An investigation of factors associated with the development of postoperative bone flap infection following decompressive craniectomy and subsequent cranioplasty.

OBJECTIVE: After a decompressive craniectomy (DC), a cranioplasty (CP) is often performed in order to improve neurosurgical outcome and cerebral blood circulation. But even though the performance of a CP subsequent to a DC has become routine medical practice, patients can in fact develop many complications from the surgery that could prolong hospitalization and lead to unfavorable prognoses. This study investigates one of the most frequent complications, bone flap infection, in order to identify prognostic factors of its development. PATIENTS AND METHODS: In this single-center study, we have retrospectively examined 329 CPs performed between 2002 and 2017. Multiple categorical and metric parameters (e.g., timing of CP, bone flap material, specific laboratory signs of infection and reason for DC) were analyzed applying unadjusted and multivariable testing. RESULTS: Bone flap infection occurred in 24 patients (7.3%). A CP performed more than six months after a DC is associated with a significantly increased risk of infection (OR = 0.308 [0.118; 0.803], p = 0.016). However, with CPs performed after twelve months, the incidence decreases, but without provable statistical impact. In addition, bone flap infection is strongly related to the neurological outcome and the material used for the skull implant, with the use of synthetic bone flaps leading to a marked increase in the rate of infection (p < 0.001). CONCLUSIONS: This study supports the hypothesis that the risk of infection is higher the longer the elapsed time between DC and CP, especially if more than six months. Based on our results, the best DC-CP time frame for keeping the infection rate low is performing the CP within the first six months after the DC. In the event that the CP cannot be performed within the first six months, a CP performed twelve months or more after the DC seems to have a favorable outcome as well.

BD-2 and BD-3 increase skin flap survival in a model of ischemia and Pseudomonas aeruginosa infection.

The main aim of this work was to study the usefulness of human ß-defensins 2 (BD-2) and 3 (BD-3), which are part of the innate immune system, in the treatment of infected ischemic skin flaps. We investigated the effect of transducing rat ischemic skin flaps with lentiviral vectors encoding human BD-2, BD-3, or both BD-2 and BD-3, to increase flap survival in the context of a P. aeruginosa infection associated with a foreign body. The secondary endpoints assessed were: bacterial counts, and biofilm formation on the surface of the foreign body. A local ischemic environment was created by producing arterialized venous flaps in the left epigastric region of rats. Flaps were intentionally infected by placing underneath them two catheters with 105 CFU of P. aeruginosa before the surgical wounds were hermetically closed. Flap biopsies were performed 3 and 7 days post-operatively, and the specimens submitted to immunohistochemical analysis for BD-2 and BD-3, as well as to bacterial quantification. Subsequently, the catheter segments were analyzed with scanning electron microscopy (SEM). Flaps transduced with BD-2 and BD-3 showed expression of these defensins and presented increased flap survival. Rats transduced with BD-3 presented a net reduction in the number of P. aeruginosa on the surface of the foreign body and lesser biofilm formation.

Unusual conservative treatment of a complicated pacemaker pocket infection: a case report.

BACKGROUND: For patients with complicated generator pocket infection, expert consensuses universally advocate complete device and leads removal followed by delayed replacement on the contralateral side. We cured our patient by partial generator removal and reimplantation of sterilized pulse generator on the ipsilateral side. We also performed a literature review about incomplete removal therapy for the management of cardiac implantable electronic device infection. CASE PRESENTATION: An 86-year-old Chinese Han man was diagnosed as having third-degree atrioventricular block and received a permanent double-chamber pacemaker in his left prepectoral area 15 years ago. Nine years later, the entire system was removed because of confirmed infection, and a new device was reimplanted in the contralateral area. He developed skin necrosis around the pacemaker pocket after 1 year, and his generator was renewed without leads extraction at another medical center. He was subsequently admitted several times for surgical tissue debridement at another institution due to extended skin necrosis. At the time of the new admission, he had severe infection, heart failure, and hypoalbuminemia. He was diagnosed as having complicated pacemaker pocket infection. Our preferred treatment strategy was for complete removal of both the generator and transvenous pacing leads, and we intended to implant an epicardial pacemaker in our patient if necessary. However, he rejected the treatment strategy and firmly refused to replace his generator. We had to attempt a novel pacemaker-preserving strategy considering our patient's severe comorbidities. Finally, we cured him by partial generator removal and reimplantation of the sterilized pulse generator on the ipsilateral side. There was no sign of wound dehiscence or infection during a 6-month follow-up. CONCLUSIONS: We would posit that partial removal of infected generators combined with conservative treatment may be a proper treatment of complicated generator pocket infection, especially for those who are susceptible to cardiac complications. Reimplantation of a sterilized pulse generator on the ipsilateral side may be an option if patients reject a new device and contralateral vascular condition is not really suitable. Opting for such treatment should be at the consideration of the primary care physician based on the condition of the patient.

Efficacy of predetermined therapeutic measures against bleb-related infection in the Collaborative Bleb-related Infection Incidence and Treatment Study.

PURPOSE: To report the efficacy of the predetermined treatment protocol of the Collaborative Bleb-related Infection Incidence and Treatment Study (CBIITS) for bleb-related infection (BRI) patients. METHODS: A prospective, observational cohort study was conducted at 34 clinical centres in Japan. Nineteen eyes from 19 patients that developed BRI were treated using the CBIITS protocol at 34 clinical centres. The visual acuity (VA) and intraocular pressure (IOP) were monitored for 6 and 12 months after treatment with the predetermined protocol. RESULTS: The logMAR was 0.623 ± 0.748 (mean ± standard deviation) before the infection developed. It was 1.054 ± 1.156 and 0.950 ± 1.168 at 6 months and 12 months post-infection, respectively. However, in subgroup analyses, there was no significant decrease in post-infection logMAR in stages I and II. In contrast, decimal VA was decreased ≥2 lines in all four cases in stage III. The IOP did not change after infection. It was 10.2 ± 5.0 mmHg (range, 3-22 mmHg) before the infection developed, and 12.9 ± 5.2 mmHg (5-24 mmHg) and 10.7 ± 4.7 mmHg (3-18 mmHg) at 6 months and 12 months after infection, respectively. CONCLUSION: Because of the small number of BRI patients, the superiority of the treatment was not definitively determined. However, VA was almost maintained in stages I and II, and the IOP did not change after infection. Although further study is necessary, the treatment protocol shown in the study might be a valuable treatment regime.

Anterior Segment Optical Coherence Tomography of Patients With Late-Onset Tunnel Fungal Infections With Endophthalmitis After Cataract Surgery.

PURPOSE: To report the use of anterior segment optical coherence tomography for characterization of late-onset tunnel fungal infections with endophthalmitis after cataract surgery. METHODS: Case reports. RESULTS: A 77-year-old female (case 1) and a 76-year-old male (case 2) who received cataract surgery 15 and 1 year before their initial visits, respectively, were treated with topical steroids based on a diagnosis of uveitis, because they showed growing white lesions on the upper iris and beneath the cataract scleral wound. Irrigation of the anterior chambers and removal of the white lesions were performed in each case, and microbiological tests were positive for fungi (case 1, a positive culture of Fusarium sp.; case 2, a filamentous fungus present in a direct smear) in the white lesions. Both cases were diagnosed as late-onset fungal endophthalmitis after cataract surgery and were treated with topical and systemic antifungal agents. However, the white lesions reappeared, and the inflammation in the anterior chambers worsened. Anterior segment optical coherence tomography showed the spread of the white lesions into the scleral incisions from cataract surgery. Deroofing of the tunnel and sclerocorneal patch grafts were performed in both cases to treat the fungal tunnel infections. After these treatments, inflammation of both corneas and anterior chambers subsided. CONCLUSIONS: Anterior segment optical coherence tomography can be used to identify late-onset fungal tunnel infections with endophthalmitis after cataract surgery.

Early post-LASIK flap amputation in the treatment of aggressive, branching keratitis: a case report.

Infectious keratitis is rare following laser vision correction. We present a case of aggressive fungal keratitis caused by Aspergillus flavus, following laser in situ keratomileusis (LASIK) in the setting of a unique environmental risk factor. We describe the key features of the acute case presentation, which guided empirical medical and surgical treatment, resulting in the most favorable outcome found in the literature, to date.

Early post-LASIK flap amputation in the treatment of aggressive, branching keratitis: a case report / Amputação precoce de pedículo de LASIK para o tratamento de ceratite ramificada agressiva: relato de caso

ABSTRACT Infectious keratitis is rare following laser vision correction. We present a case of aggressive fungal keratitis caused by Aspergillus flavus, following laser in situ keratomileusis (LASIK) in the setting of a unique environmental risk factor. We describe the key features of the acute case presentation, which guided empirical medical and surgical treatment, resulting in the most favorable outcome found in the literature, to date.

RESUMO Ceratites infecciosas são raras após a correção da visão a laser. Apresentamos um relato de caso de uma ceratite fúngica agressivo por Aspergillus flavus, após ceratomileuse a laser "in situ" (LASIK) em situação peculiar de fator de risco ambiental. Nós descrevemos as principais características da apresentação caso agudo, que orientou tratamento médico e cirúrgico empírico, demonstrando resultado mais favorável do que o encontrado na literatura até o momento.

Fluctuation of Bacteria on Bleb Surface After Trabeculectomy With Adjunctive Mitomycin C.

PURPOSE: To determine whether the bacterial and floral patterns on the bleb surface are affected by the season in eyes that had undergone trabeculectomy with adjunctive mitomycin C. PATIENTS AND METHODS: Forty-four glaucoma patients who had an avascular or a hypovascular cystic filtering bleb were studied. Swabs of the bleb surface were taken 4 times in 1 year. The samples were cultured, and all organisms isolated were identified and tested for antibiotic sensitivity and resistance. RESULTS: Of the 176 specimens, 48 tested positive in cultures. Out of the 44 glaucoma eyes that had undergone trabeculectomy, 30 (68.2%) eyes were culture positive. A total of 58 strains were isolated. The organisms isolated were 22 strains of Staphylococcus epidermidis, 21 strains of Propionibacterium acnes, 8 strains of Corynebacterium sp., 5 strains of Staphylococcus sp., and 1 strain of both Neisseria sp., and Candida parapsilosis. Fifteen eyes had a positive culture ≥2 times, and in 10 of these eyes, the same strain was isolated. There was no resistance to vancomycin by S. epidermidis, P. acnes, and Corynebacterium sp. All of the isolates of S.epidermidis were sensitive to minocycline and amikacin. The rate of bacterial detection in the spring was 13.6%, summer was 20.5%, autumn was 45.5%, and winter was 29.5%. The increase in the incidence of bacterial presence during autumn was significant (P=0.006; the Fisher exact probability test). CONCLUSIONS: It is not rare to detect the bacterial organisms on the bleb surface in glaucomatous eyes that had undergone trabeculectomy. The prevalence varied with the season and was highest in the autumn.

Transdermal application of azithromycin-amlodipine-heparin gel enhances survival of infected random ischaemic flap.

BACKGROUND: Flap necrosis is generally regarded as the result of vasospasm, thrombosis, and infection. METHODS: To improve skin flap survival and lower the risk of side effects due to systemic drug delivery, we formulated and evaluated compound gels for transdermal application. The transdermal delivery of 1% azithromycin (AZM), 0.5% amlodipine besylate (AB), and 300 IU/g low molecular weight heparin (LMWH) in compound gels, singly or in combinations, was measured across rat skin in vitro. The effects of AB and LMWH on flap blood circulation was investigated using fluorescein angiography, by transdermally applying the gel onto the surface of an in vivo ischaemic flap rat model; concentrations of the drugs were detected in both blood plasma and flap tissue at assigned timepoints. Finally, infected ischaemic flaps were treated to evaluate their anti-inflammatory effects and sizes of flap survival area. RESULTS: Each drug efficiently penetrated the in vitro skin in a time-dependent manner. In the in vivo ischaemic flaps, AB or LMWH increased the blood supply. All gel formulations that included AZM were associated with less flap inflammation. The surviving areas after treatment with AZM+LMWH or AZM+AB were significantly larger than that treated with the AZM-only gel, and the largest surviving area was that treated with AZM+AB+LMWH. Gels containing no AZM could not decrease flap inflammation or increase flap survival. CONCLUSION: Transdermal application of a compound gel with AZM, AB, and LMWH combined is a promising method to prevent and treat flap infection, improve blood circulation, and increase the survival of infected ischaemic flaps.

The Absence of Fever or Leukocytosis Does Not Exclude Infection Following Cranioplasty.

BACKGROUND: Cranioplasty encompasses various cranial reconstruction techniques that are used following craniectomy due to stroke or trauma. Despite classical infectious signs, symptoms, and radiologic findings, however, the diagnosis of infection following cranioplasty can be elusive, with the potential to result in definitive treatment delay. We sought to determine if fever or leukocytosis at presentation were indicative of infection, as well as to identify any factors that may limit its applicability. METHODS: Following institutional review board approval, a retrospective cohort of 239 patients who underwent cranioplasty following craniectomy for stroke or trauma was established from 2001-2011 at a single center (Massachusetts General Hospital). Analysis was then focused on those who developed a surgical site infection, as defined by either frank intra-operative purulence or positive intra-operative cultures, and subsequently underwent operative management. RESULTS: In 27 total cases of surgical site infection, only two had a fever and four had leukocytosis at presentation. This yielded a false-negative rate for fever of 92.6% and for leukocytosis of 85.2%. In regard to infectious etiology, 22 (81.5%) cases generated positive intra-operative cultures, with Propionibacterium acnes being the most common organism isolated. Median interval to infection was 99 days from initial cranioplasty to time of infectious presentation, and average follow-up was 3.4 years. CONCLUSIONS: The utilization of fever and elevated white blood cell count in the diagnosis of post-cranioplasty infection is associated with a high false-negative rate, making the absence of these features insufficient to exclude the diagnosis of infection.

Complications of cranioplasty using a bone flap sterilised by autoclaving following decompressive craniectomy.

BACKGROUND: Increasing use of decompressive craniectomies has led to a corresponding number of cranioplasties performed to replace the subsequent bone defect created. We aimed to evaluate the morbidity associated with cranioplasty using an autologous bone flap sterilised in an autoclave. METHODS: We retrospectively analysed data from 149 patients who underwent cranioplasty following decompressive craniectomy during the time period January 1998 to December 2012. Autologous bone flaps were sterilised in an autoclave and stored in a refrigerator at a temperature of 8 degrees above zero until cranioplasty was performed. Complications were registered and patient data were analysed in order to identify risk factors for surgical site infection and bone flap resorption after cranioplasty. Only the patients with a follow-up period of >24 months were included in the analysis of bone flap resorption (110 patients). RESULTS: Surgical side infection occurred in only five patients (3.3%), whereas bone flap resorption developed in 22 patients (20%). The multivariate analysis of the presented data identified the operating time of >120 min (p = 0.0277; OR, 16.877; 95% CI, 1.364-208.906) and the presence of diabetes mellitus (p = 0.0016; OR, 54.261; 95% CI, 4.529-650.083) as independent risk factors of development of infection and the presence of ventriculo-peritoneal (VP) shunt (p < 0.0001; OR, 35.564; 95% CI, 9.962-126.960) as independent risk factor of development of the bone flap resorption. CONCLUSIONS: Reimplantation of the autoclaved autologous bone flap following decompressive craniectomy is a simple and cheep alternative to other techniques and is available to any institution that provides autoclaving sterilisation services. This method is associated with a low rate of surgical site infection, but with a significant rate of the bone flap resorption.

Post-laser in situ keratomileusis interface fungal keratitis.

PURPOSE: To report outcomes of post-laser in situ keratomileusis (LASIK) interface filamentous fungal keratitis. METHODS: This retrospective interventional case series included 6 eyes of 5 patients with microbiologically proven post-LASIK interface fungal keratitis from August 2008 to August 2013. Patients presenting with concurrent bacterial/viral keratitis, systemic illness, prior ocular pathology, or those without a minimum follow-up of 3 months were excluded. Every case underwent microbiological scrapings from residual bed and undersurface of the flap after flap lift at presentation followed by voriconazole interface wash. Flap amputation was performed when required. The outcome measure was complete resolution of infection. RESULTS: The mean age was 24 ± 3.1 years. The male:female ratio was 4:1. The mean interval between LASIK and symptom onset was 4.16 ± 2 days; and the mean interval between symptom onset and patient referral was 3.16 ± 1.16 days. Interface scrapings showed filamentous fungal filaments in KOH wet mount. The culture grew Aspergillus in case 1 and case 5. Infiltrated LASIK flap needed to be amputated in 4 eyes of 3 patients. Voriconazole wash (100 µg/mL) of the stromal bed was performed in all cases. A positive response to therapy with resolution of infection was seen in all cases at a mean of 6.5 ± 4.6 days. No intraoperative or postoperative complications after interface scraping or voriconazole wash were observed. The final best-corrected visual acuity ranged from 20/20 to 20/80 at a mean follow-up of 9.1 ± 6.5 months. CONCLUSIONS: Post-LASIK interface fungal filamentous keratitis can present early and gives good outcomes with early microbiological diagnosis and appropriate management. Voriconazole is an efficient and probably safe adjunct in the armamentarium of corneal surgeons to treat such cases.

Surgical site infections in standard neurosurgery procedures- a study of incidence, impact and potential risk factors.

OBJECTIVES. Surgical site infections (SSIs) may be devastating for the patient and they carry high economic costs. Studies of SSI after neurosurgery report an incidence of 1-11%. However, patient material, follow-up time and definition of SSI have varied. In the present study we prospectively recorded the prevalence of SSI 3 months after standard intracranial neurosurgical procedures. The incidence, impact and risk factors of SSI were analysed. METHODS. We included patients admitted during 2010 to our unit for postoperative care after standard neurosurgical procedures. SSI was defined as evident with positive cultures from surgical samples or CSF, and/or purulent discharge during reoperation. Follow-up was done after 3 and 12 months and statistics was obtained after 3 months. The predictive values on the outcome of demographic and clinical factors describing the surgical procedure were evaluated using linear regression. RESULTS. A total of 448 patients were included in the study and underwent a total of 466 procedures. Within 3 and 12 months, 33 and 88 patients, respectively, had died. Of the surviving patients, 20 (4.3% of procedures) developed infections within 3 months and another 3 (4.9% of procedures) within 12 months. Risk factors for SSI were meningioma, longer operation time, craniotomy, dural substitute, and staples in wound closure. Patients with SSI had significantly longer hospital stay. Multivariate analysis showed that factors found significant in univariate analysis frequently occur together. DISCUSSION. We studied the prevalence of SSI after 3 and 12 months in a prospective 1-year material with standard neurosurgical procedures and found it to be 4.3% and 4.9%, respectively. The analysis of the results showed that a combination of parameters indicating a longer and more complicated procedure predicted the development of SSI. Our conclusion is that the prevention of SSI has to be done at many levels, especially with patients undergoing long surgical procedures.

Clinical, radiological, and microbiological profile of patients with autogenous cranioplasty infections.

OBJECTIVE: Bone flap infections after autogenous cranioplasty can present a diagnostic and management challenge. Little is known about the clinical, radiological, and microbiological profile of these patients. METHODS: Patients who developed bone flap infective complications requiring explantation after autogenous cranioplasties between 1999 and 2009 were identified. Their prospectively collected demographic details, clinical presentation, radiological features, surgical intervention, microbiological profile, and treatment outcomes were retrospectively reviewed. RESULTS: During the study period, 179 cranioplasties were performed with frozen autogenous skull flaps. Seventeen patients (10%, median age 25 years) experienced deep infections that necessitated flap removal and antimicrobial treatment. Although fever, swelling of the scalp, and local inflammation were present in majority of patients (76.5%), inflammatory markers were abnormal only in 33%. Computed tomography imaging features included extra-axial collection (76.5%), subgaleal collection or galeal swelling (70.6%), cerebritis (37.5%), and osteomyelitis (23.5%). Positive bacterial cultures were obtained from all (100%) explanted bone flaps, including gram-positive (82.3 %) and -negative (17.7%) organisms. A significant proportion (29.4%) of patients presented with complications late during follow-up (>6 weeks); 60% of these were attributable to Propionibacterium acnes infection. CONCLUSIONS: Clinical assessment is critical to the diagnosis of bone-flap infection. A high index of suspicion is necessary because late presentations are possible. Empirical antimicrobial treatment should include gram-negative coverage.