Establishing weight-based diagnostic reference levels for neonatal chest X-rays

INTRODUCTION

As weights among neonates can vary from <900 g to >2.5 kg, weight-based Diagnostic Reference Levels (DRLs) specific to the neonatal intensive care unit (NICU) are essential. Repeated radiation exposure to this sensitive patient group raises concerns regarding high cumulative radiation doses and the potential for long-term health detriment. This study aimed to establish weight-based DRLs for neonates undergoing mobile chest radiography (CXR) in the NICU.

METHODS

Neonates were classified into three discrete groups; <1000, 1000-2500 and >2500 g. Data were collected prospectively over three months; 95 DAP values were collected, and five were excluded due to poor technique, leaving 90 patients that met the inclusion criteria for mobile CXR in the NICU. Dose-area-product (DAP) in mGycm², the peak kilovoltage (kVp) and the product of tube current and exposure time (mAs) were retrieved from the Picture Archiving and Communication System (PACS). Images and radiological reports were also analysed to confirm diagnostic image quality (IQ). Local DRLs (LDRLs) were derived using the median DAP, and national DRLs were suggested using the 3rd quartile value.

RESULTS

The proposed LDRLs for neonates weighing <1000 g was 2.7 mGycm², for neonates weighing between 1000 g and 2500 g, it was 3.7 mGycm², and for neonates weighing >2500 g it was 6.6 mGycm². The radiation dose received by the 90 (100%) neonates included in the study fell below 11.4 mGycm²; of these, 82% of the DAP values fell below the study institution's existing LDRL of 7.25 mGycm².

CONCLUSION

Weight-based DRLs provide crucial information on doses to this specific radiation-sensitive group. This work recommends using weight-based categories for DRLs and serves as a benchmark for neonatal CXR standardisation and optimisation.

IMPLICATIONS FOR PRACTICE

The proposed weight-based DRLs can be adopted for neonates' locally, nationally and internationally.

The radiology workforce's response to the COVID-19 pandemic in the Middle East, North Africa and India

INTRODUCTION

This study aimed to investigate the response of the radiology workforce to the impact of the coronavirus disease 2019 (COVID-19) pandemic on professional practice in India and eight other Middle Eastern and North African countries. It further investigated the levels of fear and anxiety among this workforce during the pandemic.

METHODS

A quantitative cross-sectional study was conducted using an online survey from 22 May-2 June 2020 among radiology workers employed during the COVID-19 pandemic. The survey collected information related to the following themes: (1) demographic characteristics, (2) the impact of COVID-19 on radiology practice, and (3) fear and (4) anxiety emanating from the global pandemic.

RESULTS

We received 903 responses. Fifty-eight percent had completed training on infection control required for handling COVID-19 patients. A large proportion (79.5%) of the respondents strongly agreed or agreed that personal protective equipment (PPE) was adequately available at work during the pandemic. The respondents reported experiences of work-related stress (42.9%), high COVID-19 fear score (83.3%) and anxiety (10%) during the study period.

CONCLUSION

There was a perceived workload increase in general x-ray and Computed Tomography imaging procedures because they were the key modalities for the initial and follow-up investigations of COVID-19. However, there was adequate availability of PPE during the study period. Most radiology workers were afraid of being infected with the virus. Fear was predominant among workers younger than 30 years of age and also in temporary staff. Anxiety occurred completely independent of gender, age, experience, country, place of work, and work status.

IMPLICATIONS FOR PRACTICE

It is important to provide training and regular mental health support and evaluations for healthcare professionals, including radiology workers, during similar future pandemics.

The use of vacuum-assisted closure therapy for the treatment of lower-extremity wounds with exposed bone

Lower-extremity wounds with exposed tendon, bone, or orthopedic hardware present a difficult treatment challenge. In this series of patients, subatmospheric pressure therapy was applied to such lower-extremity wounds. Seventy-five patients with lower-extremity wounds, most of which were the result of trauma, were selected for this study. Dressings made of sterile open-cell foam with embedded fenestrated tubing were contoured to the wound size and placed into the wound. The site was covered with an adhesive plastic sheet. The sheet was placed beneath any external fixation devices, or the fixation device was enclosed within the sheet. The tubing was connected to the vacuum-assisted closure pump. Continuous subatmospheric suction pressure (125 mmHg) was applied to the wound site. The wounds were inspected and the dressings were changed every 48 hours.Vacuum-assisted closure therapy greatly reduced the amount of tissue edema, diminishing the circumference of the extremity and thus decreasing the surface area of the wound. Profuse granulation tissue formed rapidly, covering bone and hardware. The wounds were closed primarily and covered with split-thickness skin grafts, or a regional flap was rotated into the granulating bed to fill the defect. Successful coverage was obtained without complication in 71 of 75 patients. Wounds have been stable from 6 months up to 6 years.

Use of specialized bone screws for intermaxillary fixation

Fixation of the injured mandible to the maxilla is a proven method of stabilizing mandibular fractures and ensuring proper occlusion. The authors report their results with new specialized intraoral bone screws (IMF Screw System; Howmedica Leibinger, Inc., Carrollton, TX) that are designed for the purpose of achieving intermaxillary fixation (IMF). Nineteen patients were placed into rigid IMF using IMF screws alone. Indications were nondisplaced mandibular fractures; symphyseal, body, and angle fractures; midfacial fractures requiring temporary IMF; and edentulous patients with any of these fracture types and an adequate prosthesis. All procedures were performed with the patient under general anesthesia. The authors found that the operative time was markedly shorter than with standard IMF techniques, patient satisfaction was high, and there were no infections related to the screws. All 19 patients remained in stable, accurate occlusion and had adequate healing. One patient continues to have paraesthesias in the mental nerve distribution after screw removal. Although there is the potential for tooth and nerve injury when screws are placed improperly, the IMF Screw System seems to be a safe and reliable method of achieving secure mandibular fixation.

Uvular transposition: a new method of cleft palate repair

This prospective study was done to determine whether a new cleft palate repair utilizing uvular transposition improved speech outcome as measured objectively by a speech pathologist. In the uvular transposition procedure, the palate was lengthened with tissue from the uvula by a double-opposing Z-plasty; an intravelar veloplasty was performed, and two-thirds of the mass of the uvula was transposed to the nasal surface of the soft palate. This procedure facilitates velopharyngeal closure by significantly lengthening the palate, anatomically reconstructing the muscles of the palate, and decreasing the palatal excursion necessary to achieve closure. Sixty-two children with a cleft palate were treated with this procedure performed by the senior surgeon between the years of 1988 and 1995. These children were then enrolled in cleft lip and palate clinic at age 2 to 3 years and blindly evaluated yearly by a single speech pathologist who specialized in pediatric speech pathology. Postoperative clinical follow-up ranged from 36 to 112 months (mean, 56.8 months). Perceptual nasal emission was found to be normal in 59 of the 62 patients (95 percent). Nasometry was performed in all 62 of these patients, and the mean score was 15.7 percent, well within the accepted normal range of 25 or less at our institution. Only two of these children (3 percent) required a pharyngeal flap for velopharyngeal insufficiency. These findings suggest that the uvula transposition cleft palate repair may result in good normalization of speech with negligible rates of velopharyngeal insufficiency.

Hallermann-Streiff syndrome: experience with 15 patients and review of the literature

Hallermann-Streiff syndrome is rare, with approximately 150 case reports in the world literature. The syndrome consists of proportionate nanism; hypotrichosis; atrophy and extreme thinness of the skin, particularly over the facial area; an unusual "bird-like" face with mandibular hypoplasia; a prominent thin, pointed nose; congenital cataracts; and severe dental abnormalities. This appears to be a sporadic mutation, and the inheritance pattern is unknown. Clinical management must focus on the more life-threatening and developmental issues early on, and aesthetic deformities can be addressed after the adolescent growth period is complete. Surgical correction of cataracts should be undertaken early in life to preserve vision. Airway issues need to be addressed early. Other reconstructive procedures, including rhinoplasty, facial augmentation, and mandibular surgery, have been successful and can be performed later in life. We report on our clinical findings in 15 patients with this condition, our attempts at reconstruction, and complications we have encountered in treating this patient population. Five of our patients had produced normal chromosome studies, and none have had similarly affected siblings. Four have had normal, unaffected children. Most of our patients have undergone multiple reconstructive procedures and have done relatively well. Eleven of our patients, however, have encountered significant intermittent respiratory difficulty manifested as early feeding difficulty, recurrent upper respiratory tract infection, sleep apnea, and respiratory arrest. Three patients required tracheostomy because of respiratory difficulty, and one child died of postoperative respiratory compromise. The management of these complicated and difficult patients is discussed.

Positron emission tomography studies confirm the need for early surgical intervention in patients with single-suture craniosynostosis

Craniosynostosis, the premature fusion of one or more cranial sutures, may occur in isolation or in association with a syndromic constellation. Multiple-suture synostosis has consistently been associated with brain compression and increased intracranial pressure, and frequently decreased cognitive development. Single-suture craniosynostosis, however, has been thought by some to be an aesthetic problem with infrequent consequences on brain function and development. Some studies have disputed this concept and have argued a correlation between single-suture craniosynostosis and abnormalities in development. The purpose of this study was to determine, using an objective radiographic tool, positron emission tomography scans, if patients with single-suture craniosynostosis had any abnormalities in cerebral glucose metabolism that would indicate changes in local brain function. A total of 10 children with single-suture craniosynostosis, eight males and two females, ranging in age from 0.1 to 3.2 years, were enrolled in this prospective study approved by the Internal Review Board. Six of the children had sagittal synostosis, three had metopic synostosis, and one had coronal craniosynostosis. Each of the patients had preoperative positron emission tomography scans performed 1 to 5 weeks before cranial reconstructive surgery and postoperative scans at 6 to 12 weeks after surgery. Surgical treatment consisted of cranial vault remodeling in eight of the children and strip craniectomy with cranial expansion in two of the children. After surgery, the two scans were compared qualitatively and quantitatively by a single radiologist. The results demonstrated variable regional increases and decreases in local post-operative cerebral glucose metabolism. However, in the posterior occipital region, the area of visual development and visual spatial coordination, there was a consistent postoperative increase in all 10 patients. Maximum glucose metabolic rate was increased up to 30.2% with a mean of 9.9%, and average glucose metabolic rates demonstrated a maximum increase of up to 18.8%. The results of this study indicate cerebral glucose metabolism consistently increases in the posterior occipital cortex after surgical release of single-suture craniosynostosis. Future developmental studies are being performed to examine the functional consequences of these metabolic changes.

Use of subatmospheric pressure to prevent progression of partial-thickness burns in a swine model

The poorly understood, complex series of events that follows thermal injury frequently results in progressive loss of tissue. The concept of reversing this distinctive series of events has focused on the zone of stasis. Tissues in the zone of stasis that surround burn injuries usually die over a period of 48 to 72 hours postinjury, resulting in a more severe injury. Application of a controlled subatmospheric pressure (125 mm Hg) in an artificially closed space to partial-thickness burns in pigs significantly decreased the maximum depth of cellular death under the burn when the pressure was applied within 12 hours after burn creation (depth of control burns = 0.885 +/- 0.115 mm; subatmospheric pressure treated burns (0-hour delay) = 0.095 +/- 0.025 mm). A decrease in the depth of cell death was noted when subatmospheric pressure was applied for as little as 6 hours. In summary, the application of the negative pressure to partial-thickness burn injuries prevented progression of the wound to a deeper injury in this experimental pig model. A 12-hour working window exists between injury and treatment with reduced pressure, with an application time of as little as 6 hours for successful prevention of injury progression. This technique may represent a new, inexpensive, 'low tech' method for the treatment of partial-thickness burn injuries.

Sinus pericranii

Sinus pericranii is an anomalous extracranial vascular malformation that is in continuity with the intracranial dural venous sinuses. Five case reports, three congenital and two traumatic, are described. Clinical management, including evaluation, diagnosis, and treatment, is discussed. Awareness of this entity by plastic surgeons will allow for earlier diagnosis and appropriate surgical management, resulting in decreased risk of complications.

Cerebral perfusion defects secondary to simple craniosynostosis

Premature fusion of multiple cranial sutures has been associated with increased intracranial pressure and the potential for mental impairment. Isolated craniosynostosis, however, has been thought to be a benign condition primarily reconstructed for aesthetic purposes. On the basis of subjective developmental improvement postoperatively, an objective radiographic analysis (single positron emission computed tomography [SPECT] was used to assess differences in cerebral perfusion in the areas compressed secondary to the fused cranial suture both before and after cranial reconstructive surgery in patients with simple craniosynostosis. Seven children with craniosynostosis, six boys and one girl (age age, 3-28 months), were enrolled in this prospective study. Six of the seven had cranial asymmetry on preoperative cranial computed tomographic scans, and one had a symmetric defect and was used as a control. Each subject had a preoperative SPECT scan approximately 3 to 5 days before the cranial reconstruction procedure and a follow-up scan 6 to 10 weeks postoperatively. Preoperative asymmetries in cerebral perfusion ranged from 0 to 30% (mean, 13%) the areas compressed secondary to the premature suture fusion. In five patients cerebral blood flow, which was asymmetric before surgery, became symmetric after craniofacial reconstruction, and no new perfusion defects were documented. The control patient and one another patient had symmetric perfusion both pre- and postoperatively. Craniosynostosis may be associated with decreased cerebral blood flow as a result of the constriction of the brain from the prematurely fused suture. The correction of asymmetric cranial single-suture synostosis is more than a cosmetic procedure in that it allows for normalization of cerebral blood flow. This difference in blood flow supports early surgical intervention to prevent any potential central nervous system compromise secondary to abnormal blood flow.

Posttraumatic pseudolipoma

A pseudolipoma is a benign fatty tumor whose etiology is undetermined but is postulated to be secondary to a tear in Scarpa's fascia resulting in herniation of deeper fat through Scarpa's layer. We report ten cases of trauma that resulted in pseudolipoma formation. The literature is reviewed and treatment options are discussed.

A technique for cranial bone expansion

There are several techniques for cranial bone remodeling available to the craniofacial surgeon. We present a method for expanding the cranial bone to reconstruct large cranial defects or contour large abnormalities using a progressive series of tongue-and-groove extensions of local cranial bone plates. This technique has been used by the senior author in more than 95 cases with a 6-month to 15-year follow-up. This technique offers several advantages over traditional cranial remodeling techniques, including three-dimensional stabilization of the remodeled calvaria, use of local tissue obviating the need for distant donor tissue or nonautologous biomaterials, greater flexibility in the modeling of the cranial bone, and a controlled decrease in the size of the remaining craniectomy defects, thus improving potential for cranial bone regeneration and closure. Although cranial bone expansion is not applicable or even necessary in all craniofacial procedures, it nevertheless is a valuable tool of the craniofacial surgeon.

An increase in infant cranial deformity with supine sleeping position

Abnormalities of the occipital cranial suture in infancy can cause significant posterior cranial asymmetry, malposition of the ears, distortion of the cranial base, deformation of the forehead, and facial asymmetry. Over the past 2 years, we have noted a dramatic increase in the incidence of deformation of the occipital skull in our tertiary referral center. Our patient referral base has not changed appreciably over the past 5 years and patients have been referred from the same primary practitioner base. The timing of this increase correlates closely with the acceptance in our area of recommended changes in sleeping position to supine or side positioning for infants because of the fear of sudden infant death syndrome (SIDS). A total of 51 infants with occipital cranial deformity, with a mean age of 5.5 months at presentation, have been evaluated and treated by a single craniofacial surgeon in the 16-month period from September 1993 to December 1994. Older infants were treated with continuous positioning by the parent keeping the infant off the involved side. Younger infants and those with poor head control were treated with a soft-shell helmet. Mean timing of initial diagnosis and start of treatment was 5.5 months. Mean duration of helmet for positional treatment was 3.8 months. To date, only 3 of 51 patients have required surgical intervention, and other patients demonstrated spontaneous improvement of all measured parameters. Follow up has ranged from 8 to 24 months. We believe that most occipital plagiocephaly deformities are deformations rather than true cranio-synostoses. Despite varying amounts of suture abnormality evidenced on computed tomographic scans, most deformities can be corrected without surgery. In cases where progression of the cranial deformity occurs, despite conservative therapy, surgical intervention should be undertaken at approximately 1 year of age. The almost universal acceptance in the State of North Carolina of positioning neonates on their backs to avoid SIDS, may well increase the incidence of these deformities in the future.