Putting our heads together: The future of craniopagus twin separation.

Computer-assisted design and computer-assisted modeling (CAD/CAM), virtual surgical planning (VSP) and augmented/virtual reality (AR/VR) aid our ability to plan and perform complex craniofacial procedures. This study seeks to define the role of the aforementioned techniques in the separation of craniopagus conjoined twins. Six teams were identified who had successfully performed craniopagus twin separation with the use of CAD/CAM, VSP and/or AR/VR. Surgeons involved in separating craniopagus twins have increasingly utilized tools such as CAD/CAM models, VSP and AR/VR to plan and execute successful separation, and these tools are associated with higher success rates than historical controls.

Calcium phosphate and titanium cranioplasty after total angular craniopagus separation.

Craniopagus separation requires careful planning and a multi-staged surgical approach, managed by a multidisciplinary team. Despite growing experience on surgical management, the long-term restoration of the cranial defect has been rarely discussed so far. Several alloplastic materials have been proposed as effective and safe solutions for cranioplasty even for pediatric patients, allowing for bone generation, good aesthetic results, and low complication rates. We report, for the first time, on a separated craniopagus child who underwent successful implant of a tailor-made system based on the combination of calcium phosphate ceramic reinforced with a titanium mesh.

A Detailed Description and Discussion on Conjoined Twins.

Conjoined twins are described as having been physically fused during pregnancy and delivery. They were first mentioned a long time ago when there was not much known about this. They share some organs that are vital for survival, like the heart; these twins are almost impossible to save, but there are some cases wherein there is evidence of their survival. The article aims to present a unique discussion on conjoined twins. This article talks about the formation of conjoint twins, their types and nomenclatures, embryological concepts, past history/traditional tales, case studies, and the medical enhancements happening in this area. Both fission and fusion are thought to contribute to the disease. A monozygotic twin pregnancy cleaves when it occurs more than thirteen days after fertilization. There is just one placenta and one womb for conjoined twins (one amniotic sac). The twins that are born and stay alive after delivery usually stay alive for a few days or weeks. It's pretty rare for them to live a long prosperous life, but this article shows the otherwise, too, like the Siamese twins, which is a unique example of conjoint twins who lived for a long time. This kind of pregnancy is a complex procedure that needs to be managed by a team of professionals.

Neurosurgical Steps and Lessons Learned in Final Separation of 3-Year-Old Craniopagus Twins.

The only published paper1 describing the separation of the conjoined twins did not describe the novel steps and techniques of the microsurgery part, which lasted 26 hours. That paper did not include the neurosurgical video, either. The massive intracerebral hemorrhage that occurred on postoperative day 33 was not reported, and its potential causes have not been scrutinized. The strategy of final separation was developed during day-by-day microsurgical practice on cadavers and did lead us to novel surgical solutions as the introduction of the application of hinge and distractors. One of the twins advanced to GOS 5 status during first 5 postoperative months. The other twin slowly advanced to GOS 3 status and remained at that functional level. The latter suffered the massive brain hemorrhage on postoperative day 33, which led to delayed rehabilitation and interfered with a potentially better outcome. The thorough analysis of the potential causative factors revealed the possible pathophysiologic mechanism behind that complication.2 Two major factors have been identified, one of which is the traction-related traumatic brain injury that evolved during supine position. Another probable theory is the lack of sufficient reconstruction of the posterior part of the skull, which caused a recurring tactile microtrauma of the brain due to the supine position. The hemorrhage may have been facilitated by the fact that their coagulation tests were on the lower edge of normal parameters. It was a mistake that this part of the surgery was not performed by the neurosurgeons who designed it and practiced extensively on fresh cadavers using 3-dimensional models. Sufficient cranioplasty was performed 3 months later. It is impossible to say with certainty the cause of the hemorrhage, since there may have been other unknown causes (e.g., blood pressure spike). As a contributing factor, congestion of the veins is also possible.3 We concluded that closer monitoring, a stricter management of the interdisciplinary team work, and realizing the seriousness of the lack of sufficient structural support earlier could have prevented this unfortunate complication. In a similar case we advise future professionals to use a halo ring postoperatively for posterior protection until a sufficient cranioplasty can safely be done.

First Successful Separation of Craniopagus Twins in India-Plastic Surgical Considerations.

Separation of total vertical craniopagus with shared venous sinuses poses multiple challenges. Provision of soft-tissue cover to the exposed brains at the time of total separation is one of them, due to the large size of the defect and paucity of local tissues. Staged separation of twins is advised with partial venous and parenchymal disconnection in the first stage and total separation in the second stage. Tissue expanders are inserted in the first stage, and second stage planned to coincide with the period of adequate expansion. In the child being reported, emergency second stage was done due to the deteriorating general condition of the children. Left with inadequate expanded skin, the critical defect in a twin was managed with bilateral trapezius myocutaneous flaps. High ionotropic support of the postoperative period resulted in superficial necrosis of the flap, which was managed by debridement, allograft application and autograft later. Both twins had well-healed wounds by 3 months.

Craniopagus parasiticus: successful separation of a 28-week preterm newborn from parasite sibling twin bearing lethal congenital anomalies associated to Cantrell's pentad and sirenomelia-case-based review of the literature.

PURPOSE: This paper reviews the plausible etiological mechanisms, clinical features, preoperative analysis, and documented modern-day craniopagus parasiticus surgical separation attempts as well as an historical review of the few cases documented in the literature. METHODS: We describe the successful separation of a 28-week preterm newborn from its parasite sibling twin bearing lethal congenital anomalies associated to Cantrell's pentad and sirenomelia. Description of the case, plausible explanations on the mechanisms of conjointment along with the associated congenital abnormalities of the deceased twin are examined along with an historical revision of craniopagus parasiticus and their separation attempts with special attention to the previously undocumented attempt of the Dominican CP separation surgery by Lazareff et al. RESULTS: The use of the deceased twin cranial vault tissues (skin, bone, and duramater) as an autologous implant due to the identical genetical profile served to remodel and close the skull of the surviving twin with good esthetic results and no tissue rejection. To our knowledge, this is the youngest preterm set of craniopagus parasiticus separated in an emergency fashion with good functional and esthetic outcome. CONCLUSIONS: Craniopagus parasiticus is an infrequent subvariant of this rare form of twin conjointment which may require urgent separation due to the associated malformations of the parasitic twin; therefore, the fact that both siblings are genetically identical may prove as an advantage to use duramater, bone, and soft tissues from the parasitic twin as ideal grafts for covering the resultant defect after the separation has been performed.

Craniopagus twin: pre- and post-natal 3-dimensional virtual and physical models and virtual navigation created with free or open source software-an option for low-resource centers.

BACKGROUND: Craniopagus twins represent a rare and complex congenital malformation characterized by conjoined twins fused at the cranium. Craniopagus is challenging for patients' families and surgeons, and accurate confirmation of the extent of cranial fusion is a complex process. Most information regarding the surgical anatomy of this rare condition is obtained through analysis of ultrasonographic, magnetic resonance, or computed tomographic images. A multidisciplinary team plays a key role in obtaining such information and in parental counseling and coordination of various complex processes for optimal postnatal care of these twins. The extent of fusion is usually determined based on conventional clinical methods, such as imaging studies. METHODS: Imaging software is being used in recent times to create three-dimensional reconstruction images and for virtual navigation to investigate the skulls and brains of craniopagus twins. However, the acquisition and maintenance costs of such sophisticated medical software may be unaffordable for medical centers in developing countries. To overcome this limitation, we investigated the role of open or free source software for accurate determination of complex malformations of the skull and brain of craniopagus twins.

Pre- and Postoperative Rehabilitation of Craniopagus Conjoined Twins: A Case Report.

AIMS: Describe the pre-operative and post-operative stages of physical therapy examination, rehabilitation interventions and outcomes in craniopagus conjoined twins (CCT). METHODS: 27-months old total vertical types III CCT were admitted for surgical treatment. A structured rehabilitation program (functional mobility, balance training, sensory stimulation, communication, orthotic management, and caregiver education) was delivered post-operatively at different stages of surgery. The total duration of post-separation rehabilitation was 15 months for Twin A and 23 months for Twin B. RESULTS: Pre-operative WeeFIM was 67/126 for both the twins. Post-separation, Twin A improved to a state of complete independence in walking, step climbing, and hand function with a discharge WeeFIM score of 84/126. However, Twin B was completely dependent in bed mobility and transfer activities during discharge (WeeFIM-18/126). Minimal change in functional status was noted in Twin B (discharge FSS score-19/30). Both the twins were transferred to a regional hospital for long-term care. At 67 months of age, Twin B lost his life due to chest infection. CONCLUSIONS: Vestibular based therapies, balance, and postural control may be prioritized in the rehabilitation process of CCT. Greater communication and coordination among physical, occupational therapists and other rehabilitation professionals are recommended for successful outcome in these unique cases.

Surgical management of atlantoaxial dislocation and cervical spinal cord injury in craniopagus twins.

A case of cervical spinal cord injury in 12-year-old angular craniopagus twins is presented, with a description of the planning and execution of surgical treatment along with subsequent clinical outcome. The injury occurred following a fall from a standing position, resulting in quadriparesis in one of the twins. Imaging revealed severe craniocervical stenosis resulting from a C1-2 dislocation, and T2-weighted hyperintensity of the cervical spinal cord. After custom halo fixation was obtained, a posterior approach was utilized to decompress and instrument the occiput, cervical, and upper thoracic spine with intraoperative reduction of the dislocation. Early neurological improvement was noted during the acute postoperative phase, and 27 months of follow-up demonstrated intact instrumentation with continued neurological improvement to near baseline. The complexity of managing such an injury, inclusive of the surgical, anesthetic, biomechanical, and ethical considerations, is described in detail.

James T. Goodrich, MD, PhD, 1946-2020: a historical perspective and his contributions to craniopagus separation.

Dr. James Tait Goodrich was an internationally renowned pediatric neurosurgeon who pioneered the neurosurgical procedures for the multistage separation of craniopagus twins. As of March 2020, 59 craniopagus separations had been performed in the world, with Goodrich having performed 7 of these operations. He was the single most experienced surgeon in the field on this complex craniofacial disorder. Goodrich was a humble individual who rapidly rose through the ranks of academic neurosurgery, eventually serving as Director of the Division of Pediatric Neurosurgery at the Children's Hospital at Montefiore Medical Center in the Bronx, New York. In this historical vignette, the authors provide context into the history of and sociocultural attitudes toward conjoined twins; the epidemiology and classification of craniopagus twins; the beginnings of surgery in craniopagus twins; Goodrich's neurosurgical contributions toward advancing treatment for this complex craniofacial anomaly; and vignettes of Goodrich's unique clinical cases that made mainstream news coverage.

Two is a Crowd: Two is a Crowd: On the Enigmatic Etiopathogenesis of Conjoined Twinning.

In this article, we provide a comprehensive overview of multiple facets in the puzzling genesis of symmetrical conjoined twins. The etiopathogenesis of conjoined twins remains matter for ongoing debate and is currently cited-in virtually every paper on conjoined twins-as partial fission or secondary fusion. Both theories could potentially be extrapolated from embryological adjustments exclusively seen in conjoined twins. Adoption of these, seemingly factual, theoretical proposals has (unconsciously) resulted in crystallized patterns of verbal and graphic representations concerning the enigmatic genesis of conjoined twins. Critical evaluation on their plausibility and solidity remains however largely absent. As it appears, both the fission and fusion theories cannot be applied to the full range of conjunction possibilities and thus remain matter for persistent inconclusiveness. We propose that initial duplication of axially located morphogenetic potent primordia could be the initiating factor in the genesis of ventrally, laterally, and caudally conjoined twins. The mutual position of two primordia results in neo-axial orientation and/or interaction aplasia. Both these embryological adjustments result in conjunction patterns that may seemingly appear as being caused by fission or fusion. However, as we will substantiate, neither fission nor fusion are the cause of most conjoined twinning types; rather what is interpreted as fission or fusion is actually the result of the twinning process itself. Furthermore, we will discuss the currently held views on the origin of conjoined twins and its commonly assumed etiological correlation with monozygotic twinning. Finally, considerations are presented which indicate that the dorsal conjunction group is etiologically and pathogenetically different from other symmetric conjoined twins. This leads us to propose that dorsally united twins could actually be caused by secondary fusion of two initially separate monozygotic twins. An additional reason for the ongoing etiopathogenetic debate on the genesis of conjoined twins is because different types of conjoined twins are classically placed in one overarching receptacle, which has hindered the quest for answers. Clin. Anat. 32:722-741, 2019. © 2019 Wiley Periodicals, Inc.

A case of craniopagus parasiticus: an antenatal diagnosis by ultrasound screening at 16 weeks of gestation and a literature review of recently reported cases.

Al Yaqoubi HN, Fatema N, Al Fahdi BS. A case of craniopagus parasiticus: an antenatal diagnosis by ultrasound screening at 16 weeks of gestation and a literature review of recently reported cases. Turk J Pediatr 2019; 61: 941-945. Craniopagus parasiticus (CP) is a rare type of malformation of conjoined twins, with one degenerated or underdeveloped parasite twin united at the cranium with the other fully developed twin. Only a handful of cases have been documented in the literature to date. The incidence of this rare deformity is approximately 4 to 6 out of every 10,000,000 live births. We report on a case of CP, diagnosed at 16 weeks of gestation by ultrasound screening. To the best of our knowledge, the case that we present is the first CP case that was diagnosed at such an early gestational age. The formed fetus was found to harbour complex cardiac anomalies. In view of poor prognosis of survival after delivery and upon permission from the couple, the pregnancy was terminated at 17 weeks of gestation.

Surgical nuances in the separation of craniopagus twins - Our experience and a follow up of 15 years.

Craniopagus twins are conjoined twins fused at the cranium. This is the rarest anomaly seen in conjoined twins and craniopagus twins account for 2- 6% of conjoined twins. Conjoined twins are also extremely rare, with the anomaly seen in about 10-20 subjects per billion births. A female preponderance has been noted. Craniopagus twins can be classified into complete or partial, depending on whether or not they have shared dural venous sinuses. They can be further classified into angular or total depending on the alignment of the inter-twin longitudinal axis. Surgical separation of these cases can be an elective procedure or an emergency, mandated by the death of one of the twins. Surgical separation of craniopagus twins is a complex exercise needing detailed evaluation and planning. For the successful management of these twins, a multi-disciplinary approach involving neurosurgeons, plastic surgeons, anesthetists, radiologists, pediatric critical care specialists and ancillary staff is mandatory. We present a case of partially successful elective separation of partial angular craniopagus twins performed in 2002.The surviving twin was managed conservatively for a cerebrospinal fluid leak. The patient subsequently developed a pseudomeningocele, necessitating re-exploration, excision of the gliotic tissue, and repair of the dura and the overlying scalp flap. The patient has a skull defect for which cranioplasty has been deferred. The child is neurologically intact. The post-operative evaluation and the detailed periodic neurological assessment till date (with a follow up of 15 years) have been presented in this study.

Emergency separation of craniopagus twins: case report.

Craniopagus is a very rare congenital anomaly that tends to affect females more often than males. It is classified as partial or total. Most affected twins are either stillborn or die during the perinatal period. Those who survive birth should undergo detailed radiological evaluations soon after their condition becomes stable so that the precise anatomy of the conjoined part can be defined and surgery can be planned in detail by a multidisciplinary team. Recommendations for decreasing the risk of unsuccessful surgery include performing surgery on an elective basis after extensive preoperative radiological evaluations as well as when the twins are at an acceptable age and weight for a complex surgical separation, generally as staged procedures. In addition, the operation should be performed by a well-equipped expert multidisciplinary team. When one of the conjoined twins dies, however, surgical separation cannot be postponed because the shared circulatory system predisposes the alive child to life-threatening complications, including coagulopathy. The authors report on the successful separation of craniopagus twins performed on an emergency basis at 32 weeks of gestational age because of the sudden death of one of them. At the time of separation surgery, the twins each weighed 1250 g. To the best of the authors' knowledge, this is the youngest age and lowest weight yet reported for successful surgical separation. The surviving twin developed a pseudomeningocele, which required a second operation and placement of a cystoperitoneal shunt 4 months after the operation. Additional surgery is planned to repair a cranial defect that resulted from the pseudomeningocele, but his general physical and mental condition was otherwise good at latest follow-up (12 months after separation surgery).

Conjoined twins: From conception to separation, a review.

Conjoined twins are suggested to result from aberrant embryogenesis. The two main theories proposed to explain the phenomena are fission and fusion. The incidence rate is 1 in 50,000 births; however, since about 60% of the cases are stillborn, the true incidence is approximated at 1 in 200,000. There is a higher predisposition towards female than male gender with a ratio of 3:1. Conjoined twins are classified based upon the site of attachment. The extent of organ sharing, especially the heart, determines the possibility and prognosis of a separation procedure. Meticulous preoperative evaluation, planning, and preparedness of the team are crucial for a successful separation. Separation of conjoined twins poses several technical, legal, and ethical issues. Clin. Anat. 30:385-396, 2017. © 2017 Wiley Periodicals, Inc.

Craniopagus parasiticus - a parasitic head protruding from temporal area of cranium: a case report.

BACKGROUND: Craniopagus parasiticus is rare with an incidence of approximately four to six cases in 10,000,000 births. In our case, the head of the parasitic twin protruded from the temporal area of the normal twin's cranium. The parasitic twin had two deformed lower limbs, of which one was rudimentary, and long bones of the bilateral lower limbs and some pelvic bone. Dissection of the mass of the parasitic twin's body revealed the intestine but no chest organs or abdominal organs. There was a rudimentary labium but no vaginal opening. In resource-limited countries, maternal age or nutritional factors may play a role in craniopagus parasiticus. CASE PRESENTATION: A 38-year-old multigravida (gravida V para IV) woman of Amhara ethnicity was referred from a rural health center to our hospital due to prolonged second stage of labor at 42+1 weeks. On her arrival at our hospital, an obstetrician decided to do a caesarean section because she was unable to deliver vaginally. A live baby girl weighing 4200 g was delivered. The placenta was single and normal. Her Appearance, Pulse, Grimace, Activity, and Respiration scores were 7 and 9 at 1 and 5 minutes, respectively. She appeared to be grossly normal except for the parasitic co-twin attached to her cranium. After a week of extensive counselling and investigation, a successful separation operation was done. Postoperation, she comfortably suckled on the breast and had no neurological deficit. Two weeks after separation she was discharged in a good healthy condition with an arrangement for postnatal follow up. CONCLUSIONS: The causes of craniopagus parasiticus are still unknown due to a rarity of cases and a limited number of studies on it. There have been only nine to ten cases of craniopagus parasiticus, of which only three survived past birth and were documented in the literature. Genetic scientists and researchers continue to investigate this case because they might find explanations for the birth defect, and provide answers to improve the prognosis and the life chances of twins with craniopagus parasiticus.

Separation of Craniopagus Twins.

Separation of craniopagus twins is fraught by ethical issues. The surgery is high risk and may involve the sacrifice of one twin. We review surgical successes in separation of craniopagus twins and consider ethical and legal concepts affecting the decision to undertake such procedures. Our discussion considers how Gillett's potentiality principle and the concept of moral permissibility may be used to arrive at fair and realistic decisions.

Staged separation of craniopagus twins.

Craniopagus twins are rare and account for up to 6% of all conjoined twins. No hospital will encounter many such twins and the opportunity to develop expertise is limited. We have dealt with 2 such sets and illustrate our approach by reference to our most recent set. We believe that detailed imaging allows precise delineation of the anatomy and facilitates detailed planning of the surgery. When venous drainage from the 2 brains is connected, we believe that staged separation is preferable as gradual alteration of hemodynamics may be safer than a single-stage procedure.

Neurointerventional participation in craniopagus separation.

Craniopagus-type conjoined twins (joined at the head) are exceedingly rare. Separation of craniopagus conjoined twins is a challenging task mainly owing to complex vascular anatomy and limited experience with this disorder. Modern neuroimaging techniques including digital subtraction angiography can be used to preoperatively assess the cerebral vascular system. These techniques can also provide the raw data to fabricate three-dimensional true-scale models. We report a case in which endovascular techniques have been used in the separation of craniopagus conjoined twins. To our knowledge there are no reports of successful incorporation of neurointerventional methods in the disconnection of shared venous channels.