Congenital Nasal Pyriform Aperture Stenosis Review of Literature, Single-Center Recommendation, and Case Study

Abstract

Congenital nasal pyriform aperture stenosis (CNPAS) is a rare disorder that causes airway obstruction in newborns and children. Patients with CNPAS mainly present with nasal obstruction, respiratory distress, feeding difficulties, and/or failure to thrive. Here, we present the case of a 1-day old male baby born with tachypnea, nasal obstruction, and congestion. Clinical examination revealed subcostal retraction and nasal obstruction. Nasal examination revealed an inability to pass the neonatal scope bilaterally and narrowing of the nostrils. Imaging revealed an isolated narrowed pyriform aperture of 4.5 mm. The patient was treated conservatively, and he showed significant improvement.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12070-024-05154-0.

Introduction

Congenital nasal pyriform aperture stenosis (CNPAS) is a rare disorder that causes airway obstruction in newborns and children [1]. CNPAS, which leads to the narrowing of the anterior nasal cavity [1], was first described in 1952 by Douglas. The first radiological description of CNPAS was provided by Ey et al. in 1988 [2]. However, the first detailed clinical cases were published in 1989 by Brown et al. [3].

Patients with CNPAS mainly present with nasal obstruction, respiratory distress, feeding difficulties, and/or failure to thrive [4]. Infants are obligatory nasal breathers; therefore, any degree of nasal obstruction can lead to respiratory distress, feeding difficulties, and failure to thrive [4].

CNPAS can be isolated from or associated with midline defects [1]; however, its pathogenesis remains unknown. Furthermore, there are two embryogenesis theories. First, excessive ossification of the nasal process of the maxilla leads to overgrowth and narrowing of the pyriform aperture. Second, the insufficient growth of the palate reduces the pyriform aperture width [5]. In this study, we present a case report, literature review, and single-center recommendations for congenital nasal pyriform aperture stenosis.

Case Presentation

A 1 day-old male baby born at 38 weeks of gestation, delivered by spontaneous vaginal delivery, with a patient Apgar score of 9 and birth weight of 3.415 kg, presented with tachypnea, nasal obstruction, and congestion and was admitted into the neonatal intensive care unit (NICU) to monitor for any respiratory distress. His mother’s antenatal history was unremarkable. Clinical examination revealed subcostal retraction and nasal obstruction, but the child had no external dysmorphic features. Nasal examination revealed an inability to pass the neonatal scope bilaterally and a narrowing of the nostrils. The other ear, nose, and throat (ENT) findings were within normal limits.

Computed tomography of the paranasal sinus showed a narrowing pyriform aperture with a size of 4.5 mm (Fig. 1), and there was no solitary median maxillary central incisor. A brain magnetic resonance imaging (MRI) was performed, and the results showed no holoprosencephaly or pituitary agenesis (Fig. 2). Pituitary gland panels were within normal limits. The patient was diagnosed with an isolated congenital nasal pyriform aperture stenosis. Medical management with nasal xylometazoline, sodium chloride (NaCl), and corticosteroid drops was administered. The patient improved significantly, and tachypnea, subcostal retraction, and nasal congestion subsided. He stayed in the NICU for 17 days. He was discharged in a stable condition with red flag instructions and had regular follow-ups with the ENT and pediatric departments.

Fig. 1.

CT facial bone and paranasal sinus show a pyriform aperture width of 4.5 mm CT, computed tomography

Fig. 2.

T2 MRI brain imaging showing normal brain parenchyma, no holoprosencephaly. MRI, magnetic resonance imaging

Discussion

CNPAS is a rare cause of nasal obstruction that is estimated to occur in 1 in 25,000 live births [6]. It can be lethal if misdiagnosed or treatment is delayed, leading to ischemic brain injury and death due to respiratory distress and apnea [7]. The patient can present with respiratory distress, poor feeding, and/or failure to thrive [7]. CNPAS can be diagnosed using computed tomography, which measures the pyriform aperture width. A pyriform aperture width of < 11 mm is diagnostic. MRI plays a major role in identifying other associations, such as nasoethmoid encephaloceles, holoprosencephaly, and coloboma [7]. CNPAS can be isolated from or associated with a solitary median maxillary central incisor (SMMCI) [8]. SMMCI syndrome, named by Hall et al. [9], is a developmental defect caused by unknown events that occur between the 35th and 38th days in utero [9]. However, its etiology remains unclear. Furthermore, it is believed that the normal lateral growth of the maxillae and orbits with other midline structures in the region is slow, leading to the premature fusion of the left and right dental laminae in the midline, which prevents the normal formation of the two tooth germs for the left and right central incisors and their intervening bones and soft tissues [9]. SMMCI syndrome has been linked to syndromes and associations (CHARGE association, VACTERL association, and velocardiofacial {del(22)q11.2 syndrome}), chromosomal abnormalities {del(18p)}, r(18), del(7q 36q ter), 47XXX, del(22q11.2)), and mutations in the SHH gene [9]. In this study, we reviewed 29 articles, as summarized in Tables 1, 2, 3. CNPAS was the most common in females (75 cases [50.4%]). However, most CNPAS cases had SMMCI (77 cases [51.7%]), and most SMMCI cases had other associations or syndromes (45 cases [30.2%]). Furthermore, some patients have anatomical, functional, or combined pituitary disorders [1, 10–14]. The pyriform aperture size ranges from 2.8 to 9 mm. CNPAS is managed mainly with conservative measures, which include (nasal NaCl, corticosteroid, and decongestant drops). However, surgery must be considered if conservative management fails due to increased respiratory distress or failure to thrive. The sublabial approach is the most commonly used surgical approach [15].

Table 1.

Literature review of demographic data, clinical presentations, and CNPAS characteristics

Variable	Frequency (n)	Percentages (%)
Sex
Male	58	38.9
Female	75	50.4
Not mentioned	16	10.7
Age of evaluation (days)
Range 0–3979
Before birth	1	0.7
With 24 h of birth	65	43.6
After 24 h of birth	83	55.7
SMMCI*
Yes	77	51.7
No	72	48.3
Isolated or with associated or syndromic
isolated	39	26.2
With association or syndromic (not SMMCI)	33	22.1
SMMCI only	32	21.5
SMMCI with other association or syndromic	45	30.2
Pyriform aperture size (mm), mentioned or not
Range 2.8–9 mm	–	–
Yes	65	43.6
No	84	56.4
Management**
Conservative	18	12.1
Surgical	90	60.4
Not mentioned	40	26.8

^*Solitary median maxillary central incisor

^**1 case passed away after birth due to lobar holoprosencephaly

CNPAS, Congenital nasal pyriform aperture stenosis; SMMCI, solitary median maxillary central incisor

Table 2.

Literature review of case number, demographic data, clinical presentations, and CNPAS characteristics

Sn	Author	Case Num	Sex	Age At evaluation (days)	Symptoms	Size Pas (Mm)	Management
1	Guilmin-Crépon S et al. [1]	40	17 Males	36.5–3979	40 cases mentioned no symptoms of CNPAS	NM	NM
			23 Females		31 cases had normal pituitary function
					6 cases had combined pituitary hormone deficiency
					3 cases had isolated growth hormone deficiency
2	Sesenna E et al. [8]	3	1 male	0,0 and 34	2 cases RD	5.3,5 and 5.7	1 case of Sublabial approach with turbinate reduction and reshaping
			2 females		1 case RD, S		2 cases of Sublabial approach with turbinate reduction
3	Losken A et al. [16]	15	9 males	0	RD, FD, S and NC	NM	3 cases of Sublabial approach and choanal atresia repair
			6 females				9 cases of Sublabial approach
							2 cases of Sublabial approach and septo turbinectomy
							1 case of conservative therapy
4	Dhorje NR et al. [17]	1	male	7	RD, FD, FOT, and H	7	endonasal dilatation
5	Sitzia E et al. [18]	1	male	30	NNB, NO, RD, and FD	4.01	endonasal dilatation and neonatal palatal expander plate
6	Chen SC et al. [10]	20	8 males	65,3,4,21,	NNB, NO, RD, FD, and FOT	8,4.8,	5 cases of Conservative treatment
			12 females	1875,36,6,		4.5,7.5,	15 cases of Surgical treatment
				339,2,28,14,		6.2,7.1,
				28,21,2,1,1,		4.5,6.5,
				1,2,5 and 2		4.7,3.2,
						4.3,3.3,
						6,5,3.5
						8,4.5,6,
						3 and 3
7	Smith A et al. [19]	1	male	3	NO, RD, and FD	4	Sublabial approach
8	Van Den Abbeele T et al. [11]	20	10 males	0,11,30,0,0,	10 cases RD	NM	20 cases of Sublabial approach
			10 females	10,0,0,0,0,0	10 cases NO
				0,5,0,3,0,0,0
				0 and 0
9	Li C et al. [20]	1	female	13	RD and FD	3.3	Sublabial approach with turbinate reduction
10	Krol BJ et al. [21]	2	2 females (twins)	98 and 0	NNB, RD, and FD passed away due to Lobar holoprosencephaly at birth	NM	Sublabial approach nill
11	Amini E et al. [22]	1	male	0	RD and FD	6.3	nasal balloon dilatation
12	Somsen D et al. [23]	2	2 males	0 and 30	S, RD, and FD NNB and RD	4–6 and 5	Sublabial approach with turbinate reduction and supraglottoplasty Conservative treatment
13	Serrano TL et al. [24]	2	2 females	1 and 0	RD and FD anoxia and seizures	6.7 and 2.8	Sublabial approach with septoplasty and partial turbinectomy Sublabial approach
14	Silva DP et al. [25]	1	female	2	RD	4.7	Sublabial approach
15	Hallikainen J et al. [26]	1	female	0	RD and FD	5.3	nasal dilatation, sublabial approach and hard palate distraction
16	Abelardo E et al. [27]	1	female	0	RD and FD	5.3	nasal stent using nasal canula
17	Gandhi S et al. [28]	1	female	8	RD and FD	5.8	dilatation with stent placement
18	Fuchs F et al. [29]	1	male	diagnosed before birth	NO	5.4	conservative
19	Thomas EM et al. [30]	1	female	30	RD and FD	3	conservative
20	Kawamura T et al. [31]	1	female	0	NNB, RD, and FD	3.3	nasal dilation
21	Van Dijk FS et al. [12]	1	male	0	the left corner of the mouth droops while crying and RD	less than 8	reduction of the right concha
22	Chan EY et al. [13]	1	female	17	RD and FD	3.01	nasal dilatation and conservative
23	Blackmore K et al. [32]	1	female	0	RD	4.5	Sublabial approach and right choanal atresia dilatation
24	Gonik NJ et al. [14]	16	NM	0,3,0,30,0,0,	Second case presented with RD	4NM,7,	10 cases of Sublabial approach
				0,0,0,21,0,0	other cases NM	4,8.5,4,	6 cases of conservative treatment
				0,0,0 and 12		5.5,7.9,
						6,5,4,
						5.5,3.5
						and 5
25	Moreddu E et al. [33]	10	3 males	0	8 patients presented with RD	2NM,	8 cases of Sublabial approach
			7 females		2 patients presented with NNB	5.7,6,	2 cases of conservative treatment
						7,5,6,
						8,6 and 9
26	Vercruysse JP et al. [34]	1	Male	0	NNB, NO, RD, and FD	NM	Sublabial approach
27	Yang S et al. [35]	1	female	270	RD and FD	less than 5	Sublabial approach
28	Lahiff TJ et al. [36]	1	male	21	RD and FD	5.4	nasal dilatation
29	Osovsky M et al. [37]	1	female	0	NNB, RD, and FD	3.7	Conservative treatment

RD, Respiratory Distress; S, Stridor; NC, Nasal Congestion; FD, Feeding Difficulty; FOT, Failure to Thrive;

NO, Nasal Obstruction; NNB, Noisy Nasal Breathing; NM, Not Mentioned; H, Hypothermia; CNPAS, Congenital nasal pyriform aperture stenosis

0: within 24 h > 0: > 24 h

Table 3.

Literature review of case number and association characteristics of CNPAS

SN	Author	CN	Sex	SMMCI	Association
1	Guilmin-Crépon S et al. [1]	40	17 Males 23 Females	No	Absent pituitary, shallow sella turcica, optic nerve hypoplasia, Arnold Chiari malformation, nystagmus, strabismus Renal dysplasia, infundibular pulmonary stenosis, and RHYNS association
				Yes	Absent pituitary, shallow sella turcica, olfactory bulbs agenesis, and Arnold Chiari malformation
				Yes	Hypoplastic pituitary, shallow sella turcica, microcorie, and craniopharyngeal canal
				Yes	Hypoplastic pituitary, shallow sella turcica, Arnold Chiari malformation, and infundibular pulmonary stenosis
				Yes	Hypoplastic pituitary and coloboma
				Yes	Posterior cataract and olfactory bulbs agenesis
				Yes	Hypoplastic pituitary
				Yes	Hypoplastic pituitary and craniopharyngeal canal
				No	Nystagmus and Interventricular septal defect
				Yes	–
				Yes	Craniopharyngeal canal, Cervical intervertebral synostosis, right radial aplasia, left radial hypoplasia, atrioventricular communication, and VACTERL association
				Yes	–
				Yes	–
				Yes	Strabismus Lumbar intervertebral synostosis, sacral agenesis, thumbs’ triphalangism, hex adactylism, sigmoid kidney, tetralogy of Fallot, and VACTERL association
				No	Hypoplastic pituitary and olfactory bulbs agenesis
				Yes	Hypoplastic pituitary, olfactory bulbs agenesis, coloboma Cervico-thoracic intervertebral synostosis, asymmetry of the ears, and charge syndrome
				No	–
				Yes	–
				No	–
				No	Craniopharyngeal canal
				No	–
				Yes	Craniopharyngeal canal
				Yes	Strabismus
				No	–
				No	Hex adactylism and interauricular septal defect
				No	46XX, del(X) (p11)
				No	–
				Yes	–
				No	Olfactory bulbs agenesis Lumbar and sacral intervertebral synostosis, esophagus atresia, duplication pelvis and kidney calyces, and VACTERL association
				Yes	–
				Yes	–
				Yes	Laryngeal atresia and 22q11
				No	–
				Yes	Left ptosis
				No	–
				No	Craniopharyngeal canal
				Yes	–
				No	–
				No	Craniopharyngeal canal, microphthalmia Cervical intervertebral synostosis, partial sacral agenesis, hex adactylism, hypospadias, interauricular septal defect, and VACTERL association
				Yes	–
2	Sesenna E et al. [8]	3	Male	No	Choanal atresia
			Female	No	–
			Female	No	–
3	Losken A et al. [16]	15	Male	No	Apert, choanal atresia
			Male	No	Crouzon, choanal atresia
			Male	No	Achondroplasia, mid face hypoplasia, and choanal atresia
			Male	No	Hydrocephaly
			Male	Yes	Narrow vertical and mid-face hypoplasia
			Male	No	Mid-face hypoplasia
			Male	No	–
			Male	No	–
			Male	No	–
			Female	No	–
			Female	No	–
			Female	No	–
			Female	No	–
			Female	No	–
			Female	No	–
4	Dhorje NR et al. [17]	1	Male	Yes	–
5	Sitzia E et al. [18]	1	Male	No	–
6	Chen SC et al. [10]	20	Female	Yes	Mid-face hypoplasia, primary ciliary dyskinesia, situs inversus, and dextrocardia
			Female	Yes	Mid-face hypoplasia and ectopic posterior pituitary
			Female	Yes	Unilateral choanal atresia
			Male	Yes	–
			Female	No	Mid-face hypoplasia, hypertelorism, bilateral pre-auricular skin tag, asymmetric sensorineural hearing loss, and mild VSD
			Male	No	High arched palate and Pierre-Robin sequence
			Female	Yes	Anal atresia, rectal malformation, right dysplastic vestibule, cochlear, and semicircular canals
			Female	Yes	Nasal dermoid cyst and schizencephaly
			Female	Yes	–
			Female	No	Cardiac rhabdomyoma and possible tuberous sclerosis
			Male	Yes	Malformed ears, micro-ophthalmia, hypospadias, and Rathke’s cleft cyst in pituitary
			Female	Yes	–
			Male	No	ASD
			Female	No	–
			Male	Yes	–
			Male	No	Mid-face hypoplasia, malformed ears, craniosynostosis, Arnold-Chiari malformation, and partial agenesis of corpus callosum
			Female	Yes	Moderate ASD and VSD
			Male	No	–
			Male	Yes	–
			Female	Yes	Mid-face hypoplasia and central apnea of unknown cause
			Female	Yes	Mid-face hypoplasia, primary ciliary dyskinesia, situs inversus, and dextrocardia
7	Smith A et al. [19]	1	Male	No	–
8	Van Den Abbeele T et al. [11]	20	Male	Yes	–
			Female	Yes	–
			Male	Yes	Apert's syndrome
			Female	No	Arnold Chari and hypophysial agenesis
			Male	Yes	–
			Male	No	Hypoplastic corpus callousm
			Female	Yes	Hypophysealctopy
			Female	No	–
			Male	No	–
			Male	Yes	–
			Female	Yes	–
			Male	Yes	–
			Male	No	–
			Male	No	–
			Female	Yes	Craniosynostosis
			Male	No	–
			Female	Yes	–
			Female	Yes	–
			Female	No	–
			Female	Yes	Hypophysial agenesis
9	Li C et al. [20]	1	Female	Yes	–
10	Krol BJ et al. [21]	2	Female	Yes	–
			Female	Yes	Premaxillary agenesis, primitive ears, a wide midline cleft lip, and a narrow intraoptic distance
11	Amini E et al. [22]	1	Male	No	Short lingual frenulum
12	Somsen D et al. [23]	2	Male	No	X-linked ocular albinism (Nettleship Falls ocular) (97 kb Xp22.2 Microdeletion) albinism)
			Male	No	X-linked ocular albinism (Nettleship Falls ocular) (97 kb Xp22.2 Microdeletion) albinism)
13	Serrano TL et al. [24]	2	Female	No	Pulmonary branches, holoprosencephaly and patent oval foramen
			Female	Yes	–
14	Silva DP et al. [25]	1	Female	Yes	Absence of upper lip frenulum
15	Hallikainen J et al. [26]	1	Female	No	–
16	Abelardo E et al. [27]	1	Female	No	Bilateral sensorineural hearing loss and Waardenburg syndrome
17	Gandhi S et al. [28]	1	Female	No	–
18	Fuchs F et al. [29]	1	Male	Yes	Hypoplastic aspect of the anterior half of the nasal fossae
19	Thomas EM et al. [30]	1	Female	Yes	Dysmorphic features, microcephaly, a cone-shaped occiput, microphthalmia, proptosis, bilateral simian crease, and a depressed nasal bridge, hypotelorism, triangular hard palate, prominent median inferior palatal bony ridge, and hypoplastic maxillary sinuses
20	Kawamura T et al. [31]	1	Female	Yes	–
21	Van Dijk FS et al. [12]	1	Male	Yes	Low IGF1 (< 5 nmol/l), low-normal free T4 (12.5 pmol/l), aberrant configuration of the cavum nasi, conchae and ethmoid block and Bilateral absence of the fifth ray of the feet including the metatarsal
22	Chan EY et al. [13]	1	Female	Yes	Microcephaly, hypotelorism, semi lobar holoprosencephaly, and central diabetes insipidus
23	Blackmore K et al. [32]	1	Female	Yes	Right choanal atresia, posterior nasal septum deviation, right cochlea dysplasia, and anorectal malformation
24	Gonik NJ et al. [14]	16	NM	Yes	–
				Yes	–
				No	–
				Yes	–
				Yes	Microcephaly and Pan hypopituitary
				No	–
				No	Intestinal malrotation, dysplastic kidney and hydrocephalus
				No	–
				Yes	Bifid uvula, cranial synostosis, hypertelorism, low set ears, midface hypoplasia, Subglottic Stenosis, and Undescended testis
				No	–
				No	–
				No	Cranio-synostosis and apert syndrome
				Yes	Intestinal malrotation
				No	Solitary Nano opthalmos and Dysgenesis corpus collosum
				Yes	–
				Yes	–
25	Moreddu E et al. [33]	10	Male	No	–
			Female	No	–
			Female	Yes	–
			Male	Yes	Right Coloboma
			Female	No	–
			Female	No	–
			Female	Yes	–
			Male	Yes	Apert Syndrome and Polysyndactyly Vestibular Anomalies
			Female	No	Left-sided cophosis
			Female	Yes	–
26	Vercruysse JP et al. [34]	1	Male	No	–
27	Yang S et al. [35]	1	Female	Yes	–
28	Lahiff TJ et al. [36]	1	Male	Yes	–
29	Osovsky M et al. [37]	1	Female	Yes	–

CNPAS, Congenital nasal pyriform aperture stenosis; SMMCI, solitary median maxillary central incisor

Conclusions

Congenital nasal pyriform aperture stenosis (CNPAS) is a rare disorder that causes airway obstruction in newborns and children. It usually presents within ≥ 24 h. Patients with CNPAS mainly present with nasal obstruction, respiratory distress, feeding difficulties, and/or failure to thrive. Complete ENT examination and radiological assessment, such as sinus computed tomography and MRI, are used to diagnose and identify association and syndromic patterns. A pituitary panel should be performed for all patients with CNPAS, even those with normal MRI findings, as it can be hypofunctional. Genetic and pedigree analyses are recommended for all patients with CNPAS. However, there are no guidelines or algorithms that decide when they should be performed. Patients with CNPAS should be followed up for a long time by multidisciplinary teams to assess their medical needs.

Supplementary Information

Below is the link to the electronic supplementary material.

Funding

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Declarations

Conflict of interests

None.

Ethical Approval

This report was approved by the Ethical Committee at Crown Prince Research Center (No. 2024–817). Written informed consent was obtained from the patient’s parents for the publication of this case report and accompanying images.