Lamb's Head Research Articles

319 Validation of Lamb Head Model for Septoplasty Simulation Training

319 Validation of Lamb Head Model for Septoplasty Simulation Training

Effect of Dorsal Preservation Techniques on Septum Strength: An Experimental Animal Study.

This experimental animal model study investigates the impact of different methods employed in preservation rhinoplasty (PR) on the strength of the nasal roof, focusing on three techniques: high strip, low strip, and intermediate strip. Using 15 lamb heads as surgical models, the study addresses key questions related to the strengths of each PR techniques, the influence of septal cartilage harvesting on septum strength, and the effectiveness of spreader grafts for stability. The research involves detailed dissection steps and measurements at various nasal points, evaluating the resistance at each stage. Results indicate that the low strip technique demonstrates the most significant reduction in strength. Furthermore, the combination of PR techniques with structural grafts, specifically spreader grafts, is assessed, revealing the classical rectangular spreader graft to be more effective in stabilizing the dorsum. Despite the limitation of using the lamb heads as models, this study offers valuable insights into the effects of PR on nasal septum strength and provides a foundation for further research on the biomechanics of preservation techniques.

Lost needle in the oral cavity: can the nightmare be just a bad dream?

The loss of a scalpel or a needle during surgery can threaten the health of the patient and lead to additional costs, and radiographical assistance during surgery has been the only recovery method. This study evaluates the efficacy of a metal detector compared with conventional radiology for recovering a needle lost in the oropharynx during surgery. Different fragment sizes of needles normally used in pharyngoplasty were embedded at different locations and depths in a lamb's head. Three experienced and three junior otolaryngologists searched for the needle fragments using a metal detector and conventional radiology. All fragments were found with each method, but the mean searching time was 90 per cent shorter with the metal detector. A metal detector can be a useful tool for locating needles that break during ENT surgery, as it requires less time than conventional radiology and avoids exposing patients to radiation.

Весовой рост и убойные качества чистопородных и помесных баранчиков

Aim. Comparison of the productive qualities of purebred lambs of the Edilbay breed and crossbred animals obtained from crossing rams of the Dorper breed with ewes of the Edilbay breed. Materials and Methods. Scientific and economic experience was carried out in the conditions of the M.G. Shangeraev farm (Chernoyarsky district, Astrakhan region) on 60 heads of lambs of the Edilbay breed and Dorper-Edilbay crossbreds aged from birth to 4 months of age. Live weight of lambs was determined by individual weighing on electronic scales with an accuracy of 0.5 kg in the morning before feeding, pre-slaughter weight – after fasting for 24 hours. Meat productivity was determined by the results of the control slaughter of 3 typical lambs for each group according to the method of All-Russian Research Institute of Beef Cattle Breeding (1984). The digital material of the research was processed by the methods of variation statistics according to Plokhinsky N.A. (1969) on a PC using Microsoft Office software and determining Student's reliability criterion. Results. Under the identical growing conditions up to 4 months of age, the average live weight of crossbred lambs was 43.6 kg, which is 3.1 kg or 7.65% higher compared to purebred edilbays. Feed costs per 1 kg of live weight gain in crossbred animals were lower by 0.34 energy feed units and 36.7 g of digestible protein. The superiority of crossbred lambs over purebred animals was 2.33 kg or 11.34% in slaughter weight, and 1.68% in slaughter yield. Conclusion. The production of young lamb from purebred and crossbred animals is expedient. The best indicators of live weight and slaughter qualities had crossbred Dorper x Edilbayevsky lambs with relatively low costs of energy feed units and digestible protein per 1 kg of live weight gain.

Biomechanics of Septal L-Strut on Lamb Head Models.

It is very crucial to know the biomechanics of the septal cartilage and adjacent structures during septoplasty. The aim of this study was to investigate the strength changes of different L-strut models after mucoperichondrium elevation, application of septal extension grafts and spreader grafts on an experimental lamb model. Ten lamb heads were dissected according to a dissection protocol and septal resistances were measured with the newton meter at six zones. Three different L-strut types were designed, and all the L-strut models were created at different widths of 15mm, 10mm, and 5mm. In addition, effects of two different types of septal extension grafts and spreader grafts were compared. After mucoperichondrium elevation and harvesting the septum cartilage, there was a significant decrease in the septum resistance (p <0.05). As the width of the L-strut decreased, the septum strength decreased significantly (p <0.05). There was no significant difference between three chondrotomy types at different widths (p >0.05). There was no significant difference between the overlapping SEG and end-to-end SEG in terms of septum resistance (p >0.05). This was the first study to measure septal resistance in lamb heads. The mucoperichondrium and L-strut width were important structures for maintaining septal resistance. Chondrotomy style was not crucial, but as the width of the L-strut increased, the septal resistance increased. The septal extension grafts regardless of suturing style and the spreader grafts added strength to the caudal septum.

Lamb Head as a Training Model for Septoplasty and Rhinoplasty.

Septoplasty and rhinoplasty are difficult operations to learn and teach. Many modalities have been proposed to make the teaching process of these operations easier. In this study, it was investigated if lamb heads were good training models to teach septoplasty and rhinoplasty to trainees or experienced surgeons. In the first part of the study, 21 lamb heads were dissected according to a dissection protocol and several anatomical distances were measured to compare them with human cadavers. In the second part, eight lamb heads were dissected and different preservation rhinoplasty techniques were practiced. The study on 21 lamb heads used showed that the lateral crura were 17.8 × 11.6, the average interdomal distance was 8.1 mm, and the average domal width was 3.7 mm. The average length of the upper lateral cartilages was 31.1 mm laterally and 21.2 medially. The average length of the nasal bones was 63.9 mm, and the width was 16 mm. In the second part of the study, 8 lamb heads were used to experience where high-strip techniques were used in 5 and the Cottle technique in 3. This study revealed that lamb heads should be considered as an excellent training model for septoplasty and rhinoplasty. Its very low cost, ease of availability, and close similarity to the human cadavers can be counted as the main advantages. This study also proved that it was not only a tool for beginners, but also a very helpful tool for experienced surgeons to try new methods.

Prophylactic Effects of Ivermectin and Closantel Treatment in the Control of Oestrus ovis Infestation in Sheep.

The sheep nasal bots Oestrus ovis is parasite of the nasal cavities and sinuses of small ruminants causing oestrosis, one of the most frequent parasitic diseases in sheep and goats. The widely use of ivermectin and closantel by the sheep breeders in the treatment and prophylaxis of gastrointestinal nematodes resulted in widespread cases of anthelmintic resistance. However, there is no report about cases of O. ovis with drug-resistance. In this study, we evaluated the prophylactics and therapeutic effects of both antiparasitics in sheep with O. ovis natural infestation. The trial was carried out from early December 2019 to March 2020, with 30 crossbred males lambs allocated into three groups of 10 animals each: control (without treatment), treated with ivermectin (0.2 mg/kg subcutaneously) and treated with closantel (10 mg/kg orally). The animals were kept together grazing the same pasture area. The treatment groups were drenched in two occasions 70 days apart: on 5th December 2019 and on 13th February 2020. On 19th March 2020, all lambs were slaughtered. The lamb heads were removed and sectioned along their longitudinal and sagittal axis to search for larvae. Recovered O. ovis larvae were counted and identified according to their developmental stage (L1, L2, and L3). Seven of the control lambs were infested with O. ovis larvae ranging from six to 17 larvae (11.6 mean infestation intensity). All recovered larvae from control group were intact and active. Three animals treated with ivermectin had O. ovis larvae (1–3 larvae), however they were dead and in degeneration. The animals treated with closantel did not have any larvae. The clinical suggestive signs of oestrosis were scarce over the experimental period. The averages of daily weight gain were similar (p > 0.05) among groups. Closantel and ivermectin had high efficacy against oestrosis and O. ovis parasitism did not hinder the performance of lambs.

Insights into the mechanical interaction between an active cranial implant and the skull subjected to moderate impact loadings

In the context of cochlear implants, which are now widely used, and innovative active devices, the cranial implantation of electronic devices raises new questions about the mechanical interactions between the implant and the skull.The aim of this study was to build a methodology using experimental data and numerical simulations to evaluate the mechanical interactions between the skull and the WIMAGINE® active cranial implant intended for use for tetraplegic patients.A finite element model of the implant housing and a simplified model of the three-layered skull were developed. 2.5 J-hammer impact tests were performed on implant housings and ovine cadaver heads for model calibration. The two models were then combined to analyze the interactions between the skull and the implant and compared against impact tests.The implant dissipates a certain amount of the impact energy which could be a parameter to include in implant design in addition to the implant integrity, tending to increase the implant stiffness. The non-implanted as well as the implanted lamb heads demonstrated an overall good resistance to the impact tests. The models correlated well with the experimental data, and improvements of the model through more realistic geometry (CT-scans) and more complex material behavior could now be implemented. Such a model could then be used with human head geometries and help for future implant design optimizations using numerical models of the implant-skull and even implant-head complex.

The Estimation of Live Weight from Body Measurements in Different Meat-Type Lambs

The present study aimed to analyze the live weight (LW) and some body measurements to estimate the LW of lambs in five different meat-type sheep breeds reared in the same flock under intensive conditions. A total of 202 head of lambs, including both genders of Kivircik (K), Bandirma (B), Karacabey Merino (KM), Hampshire Down x Merino crossbreed (HM), and Ramlic (R), were conducted in this study. Birth weights ranged between 3.94-5.07 kg in those breeds and were affected significantly by breed and birth types (P<0.001). The effect of sex was clearly seen with the weaning period; males lambs were 2.61 kg heavier than female lambs (P<0.001). The importance of breed differences on chest circumference (CC) increased as the lambs grew older. On the other hand, sex had a significant effect on all body measurements at the pre- and post-weaning period (P<0.01 and P<0.001); however, did not on body length (BL) at the pre-weaning period (P>0.05). In contrast, the importance of birth type on BL and CC decreased as the lambs grew older (P>0.05). The results of regressing LW and body measurements show that LW was very highly (P<0.001) correlated with body measurements (r=0.682–0.892). The highest correlations were observed between LW and CC (r=0.802-0.892) in B, KM, and R lambs. These results suggest that using body measurements as a correction factor has a great benefit in those breeds, such as withers height and CC are used to estimate LW in KM and R lambs, effectively.

Effects of feeding Ailanthus excelsa (Roxb.) leaves on desert lamb’s feed intake, nutrients digestibility and growth performance

This trial was designed to study the effect of intake of ailanto (Ailanthus excelsa) fodder on dry matter intake, nutrients digestibility and performance of Sudanese Desert lambs. Twelve heads of lambs, six months old and weighing (17+ 0.37) kg were divided into three groups with four heads each. They were vaccinated and dosed with broad-spectrum antihelmentics (ivermectin) for treatment against internal and external parasites and ear- tagged to facilitate identification during treatments. The Ailanthus excelsa, fodder, groundnut haulms and the natural grazing was fed to group I, II and III, respectively. Water was provided continuously and feed intake was monitored daily. The feed samples were analyzed and apparent nutrients digestibility was determined by total feces collection method. This complete randomized design data was analyzed via analysis of variance and differences among means were detected using Least Significant Difference test (LSD). Feed intake was significantly (P&lt;0.05) higher for group 1 followed by the group on groundnut haulms and finally the group on the natural grazing where the amounts consumed was 865.90, 850 and 800 grams per day. Dry matter digestibility was the highest in the group on Ailanthus excelsa fodder, followed by groundnut haulms ​​and the lowest for those on natural grazing where DMD was 75.67, 67.45, and 56.45%, organic matter digestibility 78.61, 69.65 and 57.55%. Body weight changes indicated that they were higher in the Ailanthus excelsa fodder group and then in the groundnut haulms group and lower in the natural grazing group. The highest daily weight gain (60 grams) was obtained when animals fed on Ailanthus excelsa fodder compared to 45 grams and 40 grams a day for the group fed groundnut haulms and natural grazing, respectively.

Preliminary Volumetric Calculation of the Mucosal Surface in the Nares of Lambs Using a Segmentation of Computed Tomographic Images.

Intranasal vaccinations are becoming more important in both human and animal medicine to generate a localized IgA immune response not seen with parenteral vaccinations. This localized IgA response is more effective at reducing pathogen load on the mucosal surface of a potential host. One prerequisite for a successful nasal vaccination is the need to understand the distribution pattern of the nebulized vaccine, which requires an understanding the volume of the nares as well as the mucosal surface area. The exact mucosal surface area of ruminant nares has not yet been investigated. The aim of this concept study is to provide a detailed breakdown of a new method of volumetric rendering that can be used to calculate the volume and mucosal surface area of ruminant nares from computed tomographic images. The program Seg 3D was used to perform semi-automatic segmentation of a CT scan of a 9-month-old lamb head. Threshold segmentation and manual segmentation were used in combination to select the lamb's nasal cavity. The segmentation process yielded a volumetric rendering that was used to calculate the surface area and volume of the lamb's nasal cavity, with the segmentation process was repeated for each individual side of the lamb's nares. The surface area of the mucosal surface of each nostril is approximately 448 cm2, and the volume is approximately 45 cm3. The methodology described in this study successfully calculated the volume and surface area of a lamb's nares using volumetric rendering.

Training model for salvage procedures in endoscopic stapes surgery.

The learning curve in endoscopic stapes surgery, is flat and long. There is limited space during training for advanced and salvage procedures, which could be necessary in unexpected intraoperative scenarios. The aim of the present study is to develop an ex-vivo animal model for training in salvage and advanced procedures in endoscopic stapes surgery METHODS: After defining the difficult intraoperative scenarios requiring a salvage procedure during stapes surgery, we used the ovine model to create those intraoperative situations. After assessing the suitability of the model for that purpose, it was validated by subjective feedback rating (scale from 1 to 10) and by comparing the relevant anatomical structures for stapes surgery with the human. Finally, an optimal sequence of surgical steps was defined. 8 Fresh frozen lamb heads (16 ears) were studied. The selected intraoperative scenarios were: floating footplate, footplate fracture, luxation of the incus or necrosis of the long process, overhanging facial nerve, obliterative otosclerosis. The simulation resulted feasible and close to real. The mean overall rating for surgical scenarios ranged from 7.5 to 8.8 for residents and was consistent with the rating of senior surgeons, ranging from 7.67 and 9.0. Anatomical measures of the oval window area resulted similar between the ovine and the human. The ex-vivo ovine model is a suitable model for training in salvage and advanced procedures in exclusively endoscopic stapes surgery. The model can be used both for the training and maintenance of the acquired advanced skills in endoscopic stapes surgery.

Ex-vivo surgical model for "Barbed Snore Surgery": a feasibility study.

The "Barbed Snore Surgery" is one of the last technical innovations in palatal surgery for Obstructive Sleep Apnea. The availability of a low-cost surgical model able to replicate tissue consistency and main anatomical structures could be fundamental for the spreading of this surgery. The aim of this study was to assess the feasibility of an ex-vivo ovine model in the surgical training of BSS. After adequate preparation of adult lamb heads, a post-graduate student with no surgical expertise was guided by a skilled surgeon in the execution of two BSS procedures: "Barbed Roman Blinds Technique" and "Barbed Anterior Pharyngoplasty". Anatomical limitations and similarity with the human tissue were assessed and recorded during the simulation. All the procedures were successfully completed. Despite proportional differences, the palatal tissue was assessed as similar in consistency and thickness to the human tissue. The simulation was considered satisfactory and suitable for surgical training. This ex-vivo ovine surgical model could represent the right tool for BSS training thanks to readily available and inexpensive specimens. Moreover, it appears to present the realistic anatomy and tissue consistence essential for an adequate surgical simulation.

Musculoskeletal study of cebocephalic and cyclopic lamb heads illuminates links between normal and abnormal development, evolution and human pathologies

This paper is part of the emerging field of Evolutionary Developmental Pathology, dedicated to study the links between normal and abnormal development, evolution and human pathologies. We analyzed the head musculoskeletal system of several ‘natural mutant’ newborn lambs displaying various degrees of abnormality, from mild defects to cebocephaly and to cyclopia, and compared them with humans. Interestingly, muscle defects are less marked than osteological ones, and contrarily to the latter they tend to display left-right assymetries. In individuals with cebocephalic and even cyclopic skulls almost all head muscles are normal. The very few exceptions are some extraocular muscles and facial muscles that normally attach to osteological structures that are missing in the abnormal heads: such muscles are instead attached to the ‘nearest topological neighbor’ of the missing osteological structure, a pattern also found in cyclopic humans. These observations support Alberch’s ill-named “logic of monsters” - as a byproduct of strong developmental/topological constraints anatomical patterns tend to repeat themselves, even severe malformations displayed by distantly related taxa. They also support the idea that mammalian facial muscles reverted to an ancestral ‘nearest-neighbor’ muscle-bone type of attachment seen in non-vertebrate animals and in vertebrate limbs, but not in other vertebrate head muscles.

The lamb's head as an educational tool for acquiring the technical skills of septoplasty

The lamb's head as an educational tool for acquiring the technical skills of septoplasty

Personal otolaryngology–head-and-neck wet lab

Objectives: To have professional surgical instrumentational skills in a low-cost, readily available, personal wet lab, instead of having it on a real patient in the operation theatre or in the costly cadaveric workshops. This study was conducted to assess the feasibility of sheep's head as a valid ear, nose and throat (ENT) surgical training model and to establish a small yet comprehensive ENT wet laboratory. Methods: Sheep's heads, already checked by the veterinarian and safe to use, were collected from the abattoir. However, neck surgery specimens were specifically requested from butchery with more neck tissue and intact skin. Surgical instruments were collected from medical exhibitions, online and the industrial market. With the help of cheap functional industrial instruments, a personal surgical laboratory was established. Ovine specimens were evaluated for human simulation. Moreover, the applicability of most ENT procedures and operations was assessed by a team of six ENT surgeons including three junior surgeons and three senior ENT surgical consultants. Results: Utilising simple basic surgical instruments, a wide variety of surgeries performed with very similar conditions to human operations. Endoscopic procedures include middle ear surgeries, laryngeal fissure, tracheal resection and laryngotracheal reconstruction. Open surgeries, facial nerve decompression, dissection and repair were also performed. Moreover, fibre-optic intubation, fibre-optic bronchoscopy and foreign-body extraction training were tried. Some structures are very similar to human ones; some show mild-to-moderate differences, whereas few structures are totally absent in the sheep head. The consistency of, skin, subcutaneous tissues and bone are remarkably similar to that seen in humans. Lamb's heads are good and accepted substitute models for cadaveric specimens. This personal laboratory could be (at a certain level) a good substitute solution to repeated cadaveric workshops. Personal wet laboratories low-cost training improves surgical skills and if followed by few human cadaveric workshops, could enable the surgeon to start human operations with lower complication rate and shorter intervention time. Conclusion: Province otolaryngologist must build up his own experience before practicing on humans. Using sheep tissues do not carry any risks for disease transmission and are ethically defensible. Structural fresh, ovine heads provide a readily available, anatomically compatible, affordable, model for training. It could hone dexterity, surgical skills and teamwork behaviour well before venturing into real patient training. Anatomical variations in sheep's head such as mastoid, paranasal sinuses and skull base are minimal and do not affect the applicability of most of the procedures.

The Validity of Training Endoscopic Sinus and Skull Base Surgery Techniques on the Experimental Head Model.

The aim of this study was to better understand the usual learning curve in acquiring endonasal endoscopic sinus and skull base surgery (ESSBS) techniques during the novice training on the lamb's head model. Ten novices were asked to perform 10 bilateral dissections on the particular lamb's head each. The dissections were uniform, consisted of 10 well-defined steps, beginning from the simple removal of the inferior turbinate, and ending with more complicated procedures like cerebrospinal fluid leak repair, Draf 3 procedure for the frontal sinus and elevation of the nasal septal flap. The dissections have been supervised by experienced surgeons. A set of standard ESSBS instruments and 0° and 45° endoscopes have been used under the navigational system. The time required to complete each step has been measured in minutes. In general and quite expectedly, time rates have been obviously lowering as the number of the dissections performed has been growing in each of the participants. Training of the endonasal ESSBS techniques on the lamb's head proved to be useful for novices in getting basic surgical skills in the field. Because of the high degree of anatomic similarity and high level of the anatomic dimensions congruency between the lamb's head and human head (sheep's head has bigger dimensions!) it proved to be an essential preparation for the human cadaveric dissection. The median values of the time rates having been needed to complete the particular of the 10 steps in the last novices' dissections could be accepted as an orientation, just suggesting that once the time needed to complete 1 of the 10 steps has been and achieved by the particular novice, this could be an approximate sign of the maturity for the exercises on human cadaver head.

A feasible, low-cost, reproducible lamb's head model for endoscopic sinus surgery training.

ObjectiveTo describe and standardize a reproducible, viable, low-cost lamb’s head model for endoscopic sinus surgery training.MethodsOtorhinolaryngology residents performed the following three endoscopic sinus surgeries using the lamb’s head model: inferior turbinectomy, bullectomy, and maxillary antrostomy. Each student dissected 10 specimens before training these procedures on human patients, and the benefit of the animal model training was evaluated.ResultsNineteen resident physicians of comparable academic level participated in training. All participants agreed that the lamb’s head model dissections improved their skills in using surgical and videoendoscopic instruments, 90% agreed that the dissections improved their confidence with respect to training in human patients, and all stated they would recommend the same training to future residents.DiscussionLamb’s heads have been used for training in endoscopic sinus surgery. However, no standardization of this training had been performed to ensure that it is a valuable tool for learning and skill-building. The standardized method described in this study increased resident physicians’ skills and confidence before beginning their training on human patients. Moreover, our results demonstrate the feasibility of the model, considering its low cost and reproducibility.ConclusionFuture studies with this model should be conducted to assess whether the resulting increase in skills prevents and reduces medical errors, increases patient safety, reduces surgical costs, and improves the quality of otorhinolaryngological care.

The Agricultural Marketing Service Animal Handling and Welfare Red Meat Purchase Requirements: Design, Implementation, and Findings

ObjectivesThe Agricultural Marketing Service (AMS) sought to develop and implement improved animal handling and welfare (AHW) requirements for vendors who sell red meat to AMS for distribution through Federal nutrition assistance programs, including the National School Lunch Program.Materials and MethodsIn 2012, AMS undertook a meta-analysis of publically available AHW requirements, including those enshrined in Federal law, those used as industry best practices, and those required by large volume purchasers. The AMS modeled its AHW requirements for red meat vendors on the Recommended Animal Handling and Audit Guide established by the AMI Foundation. The AMS included a zero tolerance for missed stuns and for animals regaining sensibility following stunning, as observed during AMS AHW audits. The AMS also included a requirement that any stunning-related regulatory enforcement action taken by the Food Safety Inspection Service (FSIS) at an AMS vendor facility triggers a for-cause AHW audit by AMS. Trained AMS auditors performed audits at all facilities that produced beef, pork, lamb, and bison for Federal nutrition assistance programs. Data were collated and analyzed in Microsoft Excel.ResultsFrom October 2013 through December 2015, AMS performed 62 audits at beef harvest facilities, 31 audits at pork harvest facilities, 6 audits at lamb harvest facilities, and 3 audits at bison harvest facilities. Nine of the audits were triggered by FSIS regulatory enforcement actions. Auditors observed stunning of 7,908 head of cattle, 3,900 head of swine, 1,300 head of lamb, and 52 head of bison. Three missed stuns were observed and no animals were observed regaining sensibility following stunning. Data from all AMS AHW audits are available via the AMS web site (https://www.ams.usda.gov/resources/ahw).ConclusionThe AMS AHW requirements are effective. Establishments providing beef, pork, lamb, and bison to AMS for distribution through Federal nutrition assistance programs have robust AHW plans and are reliably efficient in performing the stunning process. Sharing results publicly fosters strong relationships across the stakeholder spectrum and helps ensure the credibility of the overall purchase program.

Fabrication and Microassembly of a mm-Sized Floating Probe for a Distributed Wireless Neural Interface.

A new class of wireless neural interfaces is under development in the form of tens to hundreds of mm-sized untethered implants, distributed across the target brain region(s). Unlike traditional interfaces that are tethered to a centralized control unit and suffer from micromotions that may damage the surrounding neural tissue, the new free-floating wireless implantable neural recording (FF-WINeR) probes will be stand-alone, directly communicating with an external interrogator. Towards development of the FF-WINeR, in this paper we describe the micromachining, microassembly, and hermetic packaging of 1-mm3 passive probes, each of which consists of a thinned micromachined silicon die with a centered Ø(diameter) 130 μm through-hole, an Ø81 μm sharpened tungsten electrode, a 7-turn gold wire-wound coil wrapped around the die, two 0201 surface mount capacitors on the die, and parylene-C/Polydimethylsiloxane (PDMS) coating. The fabricated passive probe is tested under a 3-coil inductive link to evaluate power transfer efficiency (PTE) and power delivered to a load (PDL) for feasibility assessment. The minimum PTE/PDL at 137 MHz were 0.76%/240 μW and 0.6%/191 μW in the air and lamb head medium, respectively, with coil separation of 2.8 cm and 9 kΩ receiver (Rx) loading. Six hermetically sealed probes went through wireless hermeticity testing, using a 2-coil inductive link under accelerated lifetime testing condition of 85 °C, 1 atm, and 100%RH. The mean-time-to-failure (MTTF) of the probes at 37 °C is extrapolated to be 28.7 years, which is over their lifetime.